diff options
58 files changed, 1946 insertions, 477 deletions
diff --git a/Documentation/Smack.txt b/Documentation/Smack.txt index 629c92e..34614b4 100644 --- a/Documentation/Smack.txt +++ b/Documentation/Smack.txt @@ -184,8 +184,9 @@ length. Single character labels using special characters, that being anything other than a letter or digit, are reserved for use by the Smack development team. Smack labels are unstructured, case sensitive, and the only operation ever performed on them is comparison for equality. Smack labels cannot -contain unprintable characters or the "/" (slash) character. Smack labels -cannot begin with a '-', which is reserved for special options. +contain unprintable characters, the "/" (slash), the "\" (backslash), the "'" +(quote) and '"' (double-quote) characters. +Smack labels cannot begin with a '-', which is reserved for special options. There are some predefined labels: @@ -523,3 +524,18 @@ Smack supports some mount options: These mount options apply to all file system types. +Smack auditing + +If you want Smack auditing of security events, you need to set CONFIG_AUDIT +in your kernel configuration. +By default, all denied events will be audited. You can change this behavior by +writing a single character to the /smack/logging file : +0 : no logging +1 : log denied (default) +2 : log accepted +3 : log denied & accepted + +Events are logged as 'key=value' pairs, for each event you at least will get +the subjet, the object, the rights requested, the action, the kernel function +that triggered the event, plus other pairs depending on the type of event +audited. diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 4a3c220..72d3bf0 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -928,6 +928,12 @@ and is between 256 and 4096 characters. It is defined in the file Formt: { "sha1" | "md5" } default: "sha1" + ima_tcb [IMA] + Load a policy which meets the needs of the Trusted + Computing Base. This means IMA will measure all + programs exec'd, files mmap'd for exec, and all files + opened for read by uid=0. + in2000= [HW,SCSI] See header of drivers/scsi/in2000.c. diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt index f11ca79..322a00bb 100644 --- a/Documentation/sysctl/kernel.txt +++ b/Documentation/sysctl/kernel.txt @@ -32,6 +32,7 @@ show up in /proc/sys/kernel: - kstack_depth_to_print [ X86 only ] - l2cr [ PPC only ] - modprobe ==> Documentation/debugging-modules.txt +- modules_disabled - msgmax - msgmnb - msgmni @@ -184,6 +185,16 @@ kernel stack. ============================================================== +modules_disabled: + +A toggle value indicating if modules are allowed to be loaded +in an otherwise modular kernel. This toggle defaults to off +(0), but can be set true (1). Once true, modules can be +neither loaded nor unloaded, and the toggle cannot be set back +to false. + +============================================================== + osrelease, ostype & version: # cat osrelease diff --git a/fs/compat.c b/fs/compat.c index 681ed81..bb2a9b2 100644 --- a/fs/compat.c +++ b/fs/compat.c @@ -1488,7 +1488,7 @@ int compat_do_execve(char * filename, if (!bprm) goto out_files; - retval = mutex_lock_interruptible(¤t->cred_exec_mutex); + retval = mutex_lock_interruptible(¤t->cred_guard_mutex); if (retval < 0) goto out_free; current->in_execve = 1; @@ -1550,7 +1550,7 @@ int compat_do_execve(char * filename, /* execve succeeded */ current->fs->in_exec = 0; current->in_execve = 0; - mutex_unlock(¤t->cred_exec_mutex); + mutex_unlock(¤t->cred_guard_mutex); acct_update_integrals(current); free_bprm(bprm); if (displaced) @@ -1573,7 +1573,7 @@ out_unmark: out_unlock: current->in_execve = 0; - mutex_unlock(¤t->cred_exec_mutex); + mutex_unlock(¤t->cred_guard_mutex); out_free: free_bprm(bprm); @@ -1016,7 +1016,7 @@ void install_exec_creds(struct linux_binprm *bprm) commit_creds(bprm->cred); bprm->cred = NULL; - /* cred_exec_mutex must be held at least to this point to prevent + /* cred_guard_mutex must be held at least to this point to prevent * ptrace_attach() from altering our determination of the task's * credentials; any time after this it may be unlocked */ @@ -1026,7 +1026,7 @@ EXPORT_SYMBOL(install_exec_creds); /* * determine how safe it is to execute the proposed program - * - the caller must hold current->cred_exec_mutex to protect against + * - the caller must hold current->cred_guard_mutex to protect against * PTRACE_ATTACH */ int check_unsafe_exec(struct linux_binprm *bprm) @@ -1268,7 +1268,7 @@ int do_execve(char * filename, if (!bprm) goto out_files; - retval = mutex_lock_interruptible(¤t->cred_exec_mutex); + retval = mutex_lock_interruptible(¤t->cred_guard_mutex); if (retval < 0) goto out_free; current->in_execve = 1; @@ -1331,7 +1331,7 @@ int do_execve(char * filename, /* execve succeeded */ current->fs->in_exec = 0; current->in_execve = 0; - mutex_unlock(¤t->cred_exec_mutex); + mutex_unlock(¤t->cred_guard_mutex); acct_update_integrals(current); free_bprm(bprm); if (displaced) @@ -1354,7 +1354,7 @@ out_unmark: out_unlock: current->in_execve = 0; - mutex_unlock(¤t->cred_exec_mutex); + mutex_unlock(¤t->cred_guard_mutex); out_free: free_bprm(bprm); diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c index c1462d4..941c842 100644 --- a/fs/hugetlbfs/inode.c +++ b/fs/hugetlbfs/inode.c @@ -30,6 +30,7 @@ #include <linux/dnotify.h> #include <linux/statfs.h> #include <linux/security.h> +#include <linux/ima.h> #include <asm/uaccess.h> @@ -986,6 +987,7 @@ struct file *hugetlb_file_setup(const char *name, size_t size, int acctflag) &hugetlbfs_file_operations); if (!file) goto out_dentry; /* inode is already attached */ + ima_counts_get(file); return file; @@ -853,7 +853,8 @@ static int __link_path_walk(const char *name, struct nameidata *nd) err = inode_permission(nd->path.dentry->d_inode, MAY_EXEC); if (!err) - err = ima_path_check(&nd->path, MAY_EXEC); + err = ima_path_check(&nd->path, MAY_EXEC, + IMA_COUNT_UPDATE); if (err) break; @@ -1515,7 +1516,8 @@ int may_open(struct path *path, int acc_mode, int flag) return error; error = ima_path_check(path, - acc_mode & (MAY_READ | MAY_WRITE | MAY_EXEC)); + acc_mode & (MAY_READ | MAY_WRITE | MAY_EXEC), + IMA_COUNT_UPDATE); if (error) return error; /* diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index b660435..bd584bc 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -55,6 +55,7 @@ #include <linux/security.h> #endif /* CONFIG_NFSD_V4 */ #include <linux/jhash.h> +#include <linux/ima.h> #include <asm/uaccess.h> @@ -735,6 +736,8 @@ nfsd_open(struct svc_rqst *rqstp, struct svc_fh *fhp, int type, flags, cred); if (IS_ERR(*filp)) host_err = PTR_ERR(*filp); + else + ima_counts_get(*filp); out_nfserr: err = nfserrno(host_err); out: @@ -2024,6 +2027,7 @@ nfsd_permission(struct svc_rqst *rqstp, struct svc_export *exp, struct dentry *dentry, int acc) { struct inode *inode = dentry->d_inode; + struct path path; int err; if (acc == NFSD_MAY_NOP) @@ -2096,7 +2100,17 @@ nfsd_permission(struct svc_rqst *rqstp, struct svc_export *exp, if (err == -EACCES && S_ISREG(inode->i_mode) && acc == (NFSD_MAY_READ | NFSD_MAY_OWNER_OVERRIDE)) err = inode_permission(inode, MAY_EXEC); + if (err) + goto nfsd_out; + /* Do integrity (permission) checking now, but defer incrementing + * IMA counts to the actual file open. + */ + path.mnt = exp->ex_path.mnt; + path.dentry = dentry; + err = ima_path_check(&path, acc & (MAY_READ | MAY_WRITE | MAY_EXEC), + IMA_COUNT_LEAVE); +nfsd_out: return err? nfserrno(err) : 0; } diff --git a/fs/proc/base.c b/fs/proc/base.c index 3326bbf..1539e63 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -2128,9 +2128,15 @@ static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf, if (copy_from_user(page, buf, count)) goto out_free; + /* Guard against adverse ptrace interaction */ + length = mutex_lock_interruptible(&task->cred_guard_mutex); + if (length < 0) + goto out_free; + length = security_setprocattr(task, (char*)file->f_path.dentry->d_name.name, (void*)page, count); + mutex_unlock(&task->cred_guard_mutex); out_free: free_page((unsigned long) page); out: diff --git a/include/linux/ima.h b/include/linux/ima.h index 0e2aa45..b1b827d 100644 --- a/include/linux/ima.h +++ b/include/linux/ima.h @@ -13,14 +13,17 @@ #include <linux/fs.h> struct linux_binprm; +#define IMA_COUNT_UPDATE 1 +#define IMA_COUNT_LEAVE 0 + #ifdef CONFIG_IMA extern int ima_bprm_check(struct linux_binprm *bprm); extern int ima_inode_alloc(struct inode *inode); extern void ima_inode_free(struct inode *inode); -extern int ima_path_check(struct path *path, int mask); +extern int ima_path_check(struct path *path, int mask, int update_counts); extern void ima_file_free(struct file *file); extern int ima_file_mmap(struct file *file, unsigned long prot); -extern void ima_shm_check(struct file *file); +extern void ima_counts_get(struct file *file); #else static inline int ima_bprm_check(struct linux_binprm *bprm) @@ -38,7 +41,7 @@ static inline void ima_inode_free(struct inode *inode) return; } -static inline int ima_path_check(struct path *path, int mask) +static inline int ima_path_check(struct path *path, int mask, int update_counts) { return 0; } @@ -53,7 +56,7 @@ static inline int ima_file_mmap(struct file *file, unsigned long prot) return 0; } -static inline void ima_shm_check(struct file *file) +static inline void ima_counts_get(struct file *file) { return; } diff --git a/include/linux/init_task.h b/include/linux/init_task.h index 889bf99..6646bfc 100644 --- a/include/linux/init_task.h +++ b/include/linux/init_task.h @@ -145,8 +145,8 @@ extern struct cred init_cred; .group_leader = &tsk, \ .real_cred = &init_cred, \ .cred = &init_cred, \ - .cred_exec_mutex = \ - __MUTEX_INITIALIZER(tsk.cred_exec_mutex), \ + .cred_guard_mutex = \ + __MUTEX_INITIALIZER(tsk.cred_guard_mutex), \ .comm = "swapper", \ .thread = INIT_THREAD, \ .fs = &init_fs, \ diff --git a/include/linux/lsm_audit.h b/include/linux/lsm_audit.h new file mode 100644 index 0000000..e461b2c --- /dev/null +++ b/include/linux/lsm_audit.h @@ -0,0 +1,111 @@ +/* + * Common LSM logging functions + * Heavily borrowed from selinux/avc.h + * + * Author : Etienne BASSET <etienne.basset@ensta.org> + * + * All credits to : Stephen Smalley, <sds@epoch.ncsc.mil> + * All BUGS to : Etienne BASSET <etienne.basset@ensta.org> + */ +#ifndef _LSM_COMMON_LOGGING_ +#define _LSM_COMMON_LOGGING_ + +#include <linux/stddef.h> +#include <linux/errno.h> +#include <linux/kernel.h> +#include <linux/kdev_t.h> +#include <linux/spinlock.h> +#include <linux/init.h> +#include <linux/audit.h> +#include <linux/in6.h> +#include <linux/path.h> +#include <linux/key.h> +#include <linux/skbuff.h> +#include <asm/system.h> + + +/* Auxiliary data to use in generating the audit record. */ +struct common_audit_data { + char type; +#define LSM_AUDIT_DATA_FS 1 +#define LSM_AUDIT_DATA_NET 2 +#define LSM_AUDIT_DATA_CAP 3 +#define LSM_AUDIT_DATA_IPC 4 +#define LSM_AUDIT_DATA_TASK 5 +#define LSM_AUDIT_DATA_KEY 6 + struct task_struct *tsk; + union { + struct { + struct path path; + struct inode *inode; + } fs; + struct { + int netif; + struct sock *sk; + u16 family; + __be16 dport; + __be16 sport; + union { + struct { + __be32 daddr; + __be32 saddr; + } v4; + struct { + struct in6_addr daddr; + struct in6_addr saddr; + } v6; + } fam; + } net; + int cap; + int ipc_id; + struct task_struct *tsk; +#ifdef CONFIG_KEYS + struct { + key_serial_t key; + char *key_desc; + } key_struct; +#endif + } u; + const char *function; + /* this union contains LSM specific data */ + union { + /* SMACK data */ + struct smack_audit_data { + char *subject; + char *object; + char *request; + int result; + } smack_audit_data; + /* SELinux data */ + struct { + u32 ssid; + u32 tsid; + u16 tclass; + u32 requested; + u32 audited; + struct av_decision *avd; + int result; + } selinux_audit_data; + } lsm_priv; + /* these callback will be implemented by a specific LSM */ + void (*lsm_pre_audit)(struct audit_buffer *, void *); + void (*lsm_post_audit)(struct audit_buffer *, void *); +}; + +#define v4info fam.v4 +#define v6info fam.v6 + +int ipv4_skb_to_auditdata(struct sk_buff *skb, + struct common_audit_data *ad, u8 *proto); + +int ipv6_skb_to_auditdata(struct sk_buff *skb, + struct common_audit_data *ad, u8 *proto); + +/* Initialize an LSM audit data structure. */ +#define COMMON_AUDIT_DATA_INIT(_d, _t) \ + { memset((_d), 0, sizeof(struct common_audit_data)); \ + (_d)->type = LSM_AUDIT_DATA_##_t; (_d)->function = __func__; } + +void common_lsm_audit(struct common_audit_data *a); + +#endif diff --git a/include/linux/magic.h b/include/linux/magic.h index 5b4e28b..927138c 100644 --- a/include/linux/magic.h +++ b/include/linux/magic.h @@ -9,6 +9,7 @@ #define DEBUGFS_MAGIC 0x64626720 #define SYSFS_MAGIC 0x62656572 #define SECURITYFS_MAGIC 0x73636673 +#define SELINUX_MAGIC 0xf97cff8c #define TMPFS_MAGIC 0x01021994 #define SQUASHFS_MAGIC 0x73717368 #define EFS_SUPER_MAGIC 0x414A53 diff --git a/include/linux/mm.h b/include/linux/mm.h index 9772d6c..ad613ed 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -581,12 +581,10 @@ static inline void set_page_links(struct page *page, enum zone_type zone, */ static inline unsigned long round_hint_to_min(unsigned long hint) { -#ifdef CONFIG_SECURITY hint &= PAGE_MASK; if (((void *)hint != NULL) && (hint < mmap_min_addr)) return PAGE_ALIGN(mmap_min_addr); -#endif return hint; } diff --git a/include/linux/sched.h b/include/linux/sched.h index d139966..42bf276 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1261,7 +1261,9 @@ struct task_struct { * credentials (COW) */ const struct cred *cred; /* effective (overridable) subjective task * credentials (COW) */ - struct mutex cred_exec_mutex; /* execve vs ptrace cred calculation mutex */ + struct mutex cred_guard_mutex; /* guard against foreign influences on + * credential calculations + * (notably. ptrace) */ char comm[TASK_COMM_LEN]; /* executable name excluding path - access with [gs]et_task_comm (which lock @@ -1901,6 +1903,7 @@ extern void sched_dead(struct task_struct *p); extern void proc_caches_init(void); extern void flush_signals(struct task_struct *); +extern void __flush_signals(struct task_struct *); extern void ignore_signals(struct task_struct *); extern void flush_signal_handlers(struct task_struct *, int force_default); extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info); diff --git a/include/linux/security.h b/include/linux/security.h index d5fd616..5eff459 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -2197,6 +2197,8 @@ static inline int security_file_mmap(struct file *file, unsigned long reqprot, unsigned long addr, unsigned long addr_only) { + if ((addr < mmap_min_addr) && !capable(CAP_SYS_RAWIO)) + return -EACCES; return 0; } @@ -384,7 +384,6 @@ static int newseg(struct ipc_namespace *ns, struct ipc_params *params) error = PTR_ERR(file); if (IS_ERR(file)) goto no_file; - ima_shm_check(file); id = ipc_addid(&shm_ids(ns), &shp->shm_perm, ns->shm_ctlmni); if (id < 0) { @@ -891,7 +890,7 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg, ulong *raddr) file = alloc_file(path.mnt, path.dentry, f_mode, &shm_file_operations); if (!file) goto out_free; - ima_shm_check(file); + ima_counts_get(file); file->private_data = sfd; file->f_mapping = shp->shm_file->f_mapping; diff --git a/kernel/cred.c b/kernel/cred.c index 3a03918..1bb4d7e 100644 --- a/kernel/cred.c +++ b/kernel/cred.c @@ -167,7 +167,7 @@ EXPORT_SYMBOL(prepare_creds); /* * Prepare credentials for current to perform an execve() - * - The caller must hold current->cred_exec_mutex + * - The caller must hold current->cred_guard_mutex */ struct cred *prepare_exec_creds(void) { @@ -276,7 +276,7 @@ int copy_creds(struct task_struct *p, unsigned long clone_flags) struct cred *new; int ret; - mutex_init(&p->cred_exec_mutex); + mutex_init(&p->cred_guard_mutex); if ( #ifdef CONFIG_KEYS diff --git a/kernel/exit.c b/kernel/exit.c index cab535c..51d1fe3 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -1472,6 +1472,7 @@ static int wait_consider_task(struct task_struct *parent, int ptrace, */ if (*notask_error) *notask_error = ret; + return 0; } if (likely(!ptrace) && unlikely(p->ptrace)) { diff --git a/kernel/module.c b/kernel/module.c index 2383e60..278e9b6 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -73,6 +73,9 @@ DEFINE_MUTEX(module_mutex); EXPORT_SYMBOL_GPL(module_mutex); static LIST_HEAD(modules); +/* Block module loading/unloading? */ +int modules_disabled = 0; + /* Waiting for a module to finish initializing? */ static DECLARE_WAIT_QUEUE_HEAD(module_wq); @@ -778,7 +781,7 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user, char name[MODULE_NAME_LEN]; int ret, forced = 0; - if (!capable(CAP_SYS_MODULE)) + if (!capable(CAP_SYS_MODULE) || modules_disabled) return -EPERM; if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0) @@ -2338,7 +2341,7 @@ SYSCALL_DEFINE3(init_module, void __user *, umod, int ret = 0; /* Must have permission */ - if (!capable(CAP_SYS_MODULE)) + if (!capable(CAP_SYS_MODULE) || modules_disabled) return -EPERM; /* Only one module load at a time, please */ diff --git a/kernel/ptrace.c b/kernel/ptrace.c index 2442d14..f6d8b8c 100644 --- a/kernel/ptrace.c +++ b/kernel/ptrace.c @@ -175,10 +175,11 @@ int ptrace_attach(struct task_struct *task) if (same_thread_group(task, current)) goto out; - /* Protect exec's credential calculations against our interference; - * SUID, SGID and LSM creds get determined differently under ptrace. + /* Protect the target's credential calculations against our + * interference; SUID, SGID and LSM creds get determined differently + * under ptrace. */ - retval = mutex_lock_interruptible(&task->cred_exec_mutex); + retval = mutex_lock_interruptible(&task->cred_guard_mutex); if (retval < 0) goto out; @@ -222,7 +223,7 @@ repeat: bad: write_unlock_irqrestore(&tasklist_lock, flags); task_unlock(task); - mutex_unlock(&task->cred_exec_mutex); + mutex_unlock(&task->cred_guard_mutex); out: return retval; } diff --git a/kernel/signal.c b/kernel/signal.c index dba6ae9..809a228 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -247,14 +247,19 @@ void flush_sigqueue(struct sigpending *queue) /* * Flush all pending signals for a task. */ +void __flush_signals(struct task_struct *t) +{ + clear_tsk_thread_flag(t, TIF_SIGPENDING); + flush_sigqueue(&t->pending); + flush_sigqueue(&t->signal->shared_pending); +} + void flush_signals(struct task_struct *t) { unsigned long flags; spin_lock_irqsave(&t->sighand->siglock, flags); - clear_tsk_thread_flag(t, TIF_SIGPENDING); - flush_sigqueue(&t->pending); - flush_sigqueue(&t->signal->shared_pending); + __flush_signals(t); spin_unlock_irqrestore(&t->sighand->siglock, flags); } diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 6a46371..944ba03 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -114,6 +114,7 @@ static int ngroups_max = NGROUPS_MAX; #ifdef CONFIG_MODULES extern char modprobe_path[]; +extern int modules_disabled; #endif #ifdef CONFIG_CHR_DEV_SG extern int sg_big_buff; @@ -534,6 +535,17 @@ static struct ctl_table kern_table[] = { .proc_handler = &proc_dostring, .strategy = &sysctl_string, }, + { + .ctl_name = CTL_UNNUMBERED, + .procname = "modules_disabled", + .data = &modules_disabled, + .maxlen = sizeof(int), + .mode = 0644, + /* only handle a transition from default "0" to "1" */ + .proc_handler = &proc_dointvec_minmax, + .extra1 = &one, + .extra2 = &one, + }, #endif #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET) { @@ -1233,7 +1245,6 @@ static struct ctl_table vm_table[] = { .strategy = &sysctl_jiffies, }, #endif -#ifdef CONFIG_SECURITY { .ctl_name = CTL_UNNUMBERED, .procname = "mmap_min_addr", @@ -1242,7 +1253,6 @@ static struct ctl_table vm_table[] = { .mode = 0644, .proc_handler = &proc_doulongvec_minmax, }, -#endif #ifdef CONFIG_NUMA { .ctl_name = CTL_UNNUMBERED, @@ -226,6 +226,25 @@ config HAVE_MLOCKED_PAGE_BIT config MMU_NOTIFIER bool +config DEFAULT_MMAP_MIN_ADDR + int "Low address space to protect from user allocation" + default 4096 + help + This is the portion of low virtual memory which should be protected + from userspace allocation. Keeping a user from writing to low pages + can help reduce the impact of kernel NULL pointer bugs. + + For most ia64, ppc64 and x86 users with lots of address space + a value of 65536 is reasonable and should cause no problems. + On arm and other archs it should not be higher than 32768. + Programs which use vm86 functionality would either need additional + permissions from either the LSM or the capabilities module or have + this protection disabled. + + This value can be changed after boot using the + /proc/sys/vm/mmap_min_addr tunable. + + config NOMMU_INITIAL_TRIM_EXCESS int "Turn on mmap() excess space trimming before booting" depends on !MMU @@ -87,6 +87,9 @@ int sysctl_overcommit_ratio = 50; /* default is 50% */ int sysctl_max_map_count __read_mostly = DEFAULT_MAX_MAP_COUNT; struct percpu_counter vm_committed_as; +/* amount of vm to protect from userspace access */ +unsigned long mmap_min_addr = CONFIG_DEFAULT_MMAP_MIN_ADDR; + /* * Check that a process has enough memory to allocate a new virtual * mapping. 0 means there is enough memory for the allocation to @@ -69,6 +69,9 @@ int sysctl_max_map_count = DEFAULT_MAX_MAP_COUNT; int sysctl_nr_trim_pages = CONFIG_NOMMU_INITIAL_TRIM_EXCESS; int heap_stack_gap = 0; +/* amount of vm to protect from userspace access */ +unsigned long mmap_min_addr = CONFIG_DEFAULT_MMAP_MIN_ADDR; + atomic_long_t mmap_pages_allocated; EXPORT_SYMBOL(mem_map); @@ -2659,6 +2659,7 @@ struct file *shmem_file_setup(char *name, loff_t size, unsigned long flags) if (error) goto close_file; #endif + ima_counts_get(file); return file; close_file: @@ -2684,7 +2685,6 @@ int shmem_zero_setup(struct vm_area_struct *vma) if (IS_ERR(file)) return PTR_ERR(file); - ima_shm_check(file); if (vma->vm_file) fput(vma->vm_file); vma->vm_file = file; diff --git a/security/Kconfig b/security/Kconfig index bb24477..d23c839 100644 --- a/security/Kconfig +++ b/security/Kconfig @@ -110,28 +110,8 @@ config SECURITY_ROOTPLUG See <http://www.linuxjournal.com/article.php?sid=6279> for more information about this module. - - If you are unsure how to answer this question, answer N. - -config SECURITY_DEFAULT_MMAP_MIN_ADDR - int "Low address space to protect from user allocation" - depends on SECURITY - default 0 - help - This is the portion of low virtual memory which should be protected - from userspace allocation. Keeping a user from writing to low pages - can help reduce the impact of kernel NULL pointer bugs. - - For most ia64, ppc64 and x86 users with lots of address space - a value of 65536 is reasonable and should cause no problems. - On arm and other archs it should not be higher than 32768. - Programs which use vm86 functionality would either need additional - permissions from either the LSM or the capabilities module or have - this protection disabled. - - This value can be changed after boot using the - /proc/sys/vm/mmap_min_addr tunable. + If you are unsure how to answer this question, answer N. source security/selinux/Kconfig source security/smack/Kconfig diff --git a/security/Makefile b/security/Makefile index fa77021..c67557c 100644 --- a/security/Makefile +++ b/security/Makefile @@ -16,6 +16,9 @@ obj-$(CONFIG_SECURITYFS) += inode.o # Must precede capability.o in order to stack properly. obj-$(CONFIG_SECURITY_SELINUX) += selinux/built-in.o obj-$(CONFIG_SECURITY_SMACK) += smack/built-in.o +ifeq ($(CONFIG_AUDIT),y) +obj-$(CONFIG_SECURITY_SMACK) += lsm_audit.o +endif obj-$(CONFIG_SECURITY_TOMOYO) += tomoyo/built-in.o obj-$(CONFIG_SECURITY_ROOTPLUG) += root_plug.o obj-$(CONFIG_CGROUP_DEVICE) += device_cgroup.o diff --git a/security/commoncap.c b/security/commoncap.c index beac025..48b7e02 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -28,6 +28,28 @@ #include <linux/prctl.h> #include <linux/securebits.h> +/* + * If a non-root user executes a setuid-root binary in + * !secure(SECURE_NOROOT) mode, then we raise capabilities. + * However if fE is also set, then the intent is for only + * the file capabilities to be applied, and the setuid-root + * bit is left on either to change the uid (plausible) or + * to get full privilege on a kernel without file capabilities + * support. So in that case we do not raise capabilities. + * + * Warn if that happens, once per boot. + */ +static void warn_setuid_and_fcaps_mixed(char *fname) +{ + static int warned; + if (!warned) { + printk(KERN_INFO "warning: `%s' has both setuid-root and" + " effective capabilities. Therefore not raising all" + " capabilities.\n", fname); + warned = 1; + } +} + int cap_netlink_send(struct sock *sk, struct sk_buff *skb) { NETLINK_CB(skb).eff_cap = current_cap(); @@ -464,6 +486,15 @@ int cap_bprm_set_creds(struct linux_binprm *bprm) if (!issecure(SECURE_NOROOT)) { /* + * If the legacy file capability is set, then don't set privs + * for a setuid root binary run by a non-root user. Do set it + * for a root user just to cause least surprise to an admin. + */ + if (effective && new->uid != 0 && new->euid == 0) { + warn_setuid_and_fcaps_mixed(bprm->filename); + goto skip; + } + /* * To support inheritance of root-permissions and suid-root * executables under compatibility mode, we override the * capability sets for the file. @@ -478,6 +509,7 @@ int cap_bprm_set_creds(struct linux_binprm *bprm) if (new->euid == 0) effective = true; } +skip: /* Don't let someone trace a set[ug]id/setpcap binary with the revised * credentials unless they have the appropriate permit diff --git a/security/inode.c b/security/inode.c index f3b91bf..f7496c6 100644 --- a/security/inode.c +++ b/security/inode.c @@ -287,7 +287,7 @@ void securityfs_remove(struct dentry *dentry) { struct dentry *parent; - if (!dentry) + if (!dentry || IS_ERR(dentry)) return; parent = dentry->d_parent; diff --git a/security/integrity/ima/ima_audit.c b/security/integrity/ima/ima_audit.c index 1e082bb..ff513ff 100644 --- a/security/integrity/ima/ima_audit.c +++ b/security/integrity/ima/ima_audit.c @@ -22,18 +22,9 @@ static int ima_audit; static int __init ima_audit_setup(char *str) { unsigned long audit; - int rc, result = 0; - char *op = "ima_audit"; - char *cause; - rc = strict_strtoul(str, 0, &audit); - if (rc || audit > 1) - result = 1; - else - ima_audit = audit; - cause = ima_audit ? "enabled" : "not_enabled"; - integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL, NULL, - op, cause, result, 0); + if (!strict_strtoul(str, 0, &audit)) + ima_audit = audit ? 1 : 0; return 1; } __setup("ima_audit=", ima_audit_setup); @@ -50,23 +41,14 @@ void integrity_audit_msg(int audit_msgno, struct inode *inode, ab = audit_log_start(current->audit_context, GFP_KERNEL, audit_msgno); audit_log_format(ab, "integrity: pid=%d uid=%u auid=%u ses=%u", - current->pid, current->cred->uid, + current->pid, current_cred()->uid, audit_get_loginuid(current), audit_get_sessionid(current)); audit_log_task_context(ab); - switch (audit_msgno) { - case AUDIT_INTEGRITY_DATA: - case AUDIT_INTEGRITY_METADATA: - case AUDIT_INTEGRITY_PCR: - case AUDIT_INTEGRITY_STATUS: - audit_log_format(ab, " op=%s cause=%s", op, cause); - break; - case AUDIT_INTEGRITY_HASH: - audit_log_format(ab, " op=%s hash=%s", op, cause); - break; - default: - audit_log_format(ab, " op=%s", op); - } + audit_log_format(ab, " op="); + audit_log_string(ab, op); + audit_log_format(ab, " cause="); + audit_log_string(ab, cause); audit_log_format(ab, " comm="); audit_log_untrustedstring(ab, current->comm); if (fname) { diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c index 50d572b..63003a6 100644 --- a/security/integrity/ima/ima_crypto.c +++ b/security/integrity/ima/ima_crypto.c @@ -103,7 +103,7 @@ int ima_calc_template_hash(int template_len, void *template, char *digest) return rc; } -static void ima_pcrread(int idx, u8 *pcr) +static void __init ima_pcrread(int idx, u8 *pcr) { if (!ima_used_chip) return; @@ -115,7 +115,7 @@ static void ima_pcrread(int idx, u8 *pcr) /* * Calculate the boot aggregate hash */ -int ima_calc_boot_aggregate(char *digest) +int __init ima_calc_boot_aggregate(char *digest) { struct hash_desc desc; struct scatterlist sg; diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c index 510186f..6bfc7ea 100644 --- a/security/integrity/ima/ima_fs.c +++ b/security/integrity/ima/ima_fs.c @@ -15,6 +15,7 @@ * implemenents security file system for reporting * current measurement list and IMA statistics */ +#include <linux/fcntl.h> #include <linux/module.h> #include <linux/seq_file.h> #include <linux/rculist.h> @@ -283,6 +284,9 @@ static atomic_t policy_opencount = ATOMIC_INIT(1); */ int ima_open_policy(struct inode * inode, struct file * filp) { + /* No point in being allowed to open it if you aren't going to write */ + if (!(filp->f_flags & O_WRONLY)) + return -EACCES; if (atomic_dec_and_test(&policy_opencount)) return 0; return -EBUSY; @@ -315,7 +319,7 @@ static struct file_operations ima_measure_policy_ops = { .release = ima_release_policy }; -int ima_fs_init(void) +int __init ima_fs_init(void) { ima_dir = securityfs_create_dir("ima", NULL); if (IS_ERR(ima_dir)) @@ -349,7 +353,7 @@ int ima_fs_init(void) goto out; ima_policy = securityfs_create_file("policy", - S_IRUSR | S_IRGRP | S_IWUSR, + S_IWUSR, ima_dir, NULL, &ima_measure_policy_ops); if (IS_ERR(ima_policy)) diff --git a/security/integrity/ima/ima_iint.c b/security/integrity/ima/ima_iint.c index ec79f1e..b8dd693 100644 --- a/security/integrity/ima/ima_iint.c +++ b/security/integrity/ima/ima_iint.c @@ -196,7 +196,7 @@ static void init_once(void *foo) kref_set(&iint->refcount, 1); } -void ima_iintcache_init(void) +void __init ima_iintcache_init(void) { iint_cache = kmem_cache_create("iint_cache", sizeof(struct ima_iint_cache), 0, diff --git a/security/integrity/ima/ima_init.c b/security/integrity/ima/ima_init.c index 0b0bb8c..a40da7a 100644 --- a/security/integrity/ima/ima_init.c +++ b/security/integrity/ima/ima_init.c @@ -38,7 +38,7 @@ int ima_used_chip; * a different value.) Violations add a zero entry to the measurement * list and extend the aggregate PCR value with ff...ff's. */ -static void ima_add_boot_aggregate(void) +static void __init ima_add_boot_aggregate(void) { struct ima_template_entry *entry; const char *op = "add_boot_aggregate"; @@ -71,7 +71,7 @@ err_out: audit_cause, result, 0); } -int ima_init(void) +int __init ima_init(void) { u8 pcr_i[IMA_DIGEST_SIZE]; int rc; diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index f4e7266..6f61187 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -29,20 +29,8 @@ int ima_initialized; char *ima_hash = "sha1"; static int __init hash_setup(char *str) { - const char *op = "hash_setup"; - const char *hash = "sha1"; - int result = 0; - int audit_info = 0; - - if (strncmp(str, "md5", 3) == 0) { - hash = "md5"; - ima_hash = str; - } else if (strncmp(str, "sha1", 4) != 0) { - hash = "invalid_hash_type"; - result = 1; - } - integrity_audit_msg(AUDIT_INTEGRITY_HASH, NULL, NULL, op, hash, - result, audit_info); + if (strncmp(str, "md5", 3) == 0) + ima_hash = "md5"; return 1; } __setup("ima_hash=", hash_setup); @@ -128,10 +116,6 @@ static int get_path_measurement(struct ima_iint_cache *iint, struct file *file, { int rc = 0; - if (IS_ERR(file)) { - pr_info("%s dentry_open failed\n", filename); - return rc; - } iint->opencount++; iint->readcount++; @@ -141,6 +125,15 @@ static int get_path_measurement(struct ima_iint_cache *iint, struct file *file, return rc; } +static void ima_update_counts(struct ima_iint_cache *iint, int mask) +{ + iint->opencount++; + if ((mask & MAY_WRITE) || (mask == 0)) + iint->writecount++; + else if (mask & (MAY_READ | MAY_EXEC)) + iint->readcount++; +} + /** * ima_path_check - based on policy, collect/store measurement. * @path: contains a pointer to the path to be measured @@ -156,10 +149,10 @@ static int get_path_measurement(struct ima_iint_cache *iint, struct file *file, * - Opening a file for read when already open for write, * could result in a file measurement error. * - * Return 0 on success, an error code on failure. - * (Based on the results of appraise_measurement().) + * Always return 0 and audit dentry_open failures. + * (Return code will be based upon measurement appraisal.) */ -int ima_path_check(struct path *path, int mask) +int ima_path_check(struct path *path, int mask, int update_counts) { struct inode *inode = path->dentry->d_inode; struct ima_iint_cache *iint; @@ -173,11 +166,8 @@ int ima_path_check(struct path *path, int mask) return 0; mutex_lock(&iint->mutex); - iint->opencount++; - if ((mask & MAY_WRITE) || (mask == 0)) - iint->writecount++; - else if (mask & (MAY_READ | MAY_EXEC)) - iint->readcount++; + if (update_counts) + ima_update_counts(iint, mask); rc = ima_must_measure(iint, inode, MAY_READ, PATH_CHECK); if (rc < 0) @@ -196,7 +186,19 @@ int ima_path_check(struct path *path, int mask) struct dentry *dentry = dget(path->dentry); struct vfsmount *mnt = mntget(path->mnt); - file = dentry_open(dentry, mnt, O_RDONLY, current->cred); + file = dentry_open(dentry, mnt, O_RDONLY | O_LARGEFILE, + current_cred()); + if (IS_ERR(file)) { + int audit_info = 0; + + integrity_audit_msg(AUDIT_INTEGRITY_PCR, inode, + dentry->d_name.name, + "add_measurement", + "dentry_open failed", + 1, audit_info); + file = NULL; + goto out; + } rc = get_path_measurement(iint, file, dentry->d_name.name); } out: @@ -206,6 +208,7 @@ out: kref_put(&iint->refcount, iint_free); return 0; } +EXPORT_SYMBOL_GPL(ima_path_check); static int process_measurement(struct file *file, const unsigned char *filename, int mask, int function) @@ -234,7 +237,16 @@ out: return rc; } -static void opencount_get(struct file *file) +/* + * ima_opens_get - increment file counts + * + * - for IPC shm and shmat file. + * - for nfsd exported files. + * + * Increment the counts for these files to prevent unnecessary + * imbalance messages. + */ +void ima_counts_get(struct file *file) { struct inode *inode = file->f_dentry->d_inode; struct ima_iint_cache *iint; @@ -246,8 +258,14 @@ static void opencount_get(struct file *file) return; mutex_lock(&iint->mutex); iint->opencount++; + if ((file->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ) + iint->readcount++; + + if (file->f_mode & FMODE_WRITE) + iint->writecount++; mutex_unlock(&iint->mutex); } +EXPORT_SYMBOL_GPL(ima_counts_get); /** * ima_file_mmap - based on policy, collect/store measurement. @@ -272,18 +290,6 @@ int ima_file_mmap(struct file *file, unsigned long prot) return 0; } -/* - * ima_shm_check - IPC shm and shmat create/fput a file - * - * Maintain the opencount for these files to prevent unnecessary - * imbalance messages. - */ -void ima_shm_check(struct file *file) -{ - opencount_get(file); - return; -} - /** * ima_bprm_check - based on policy, collect/store measurement. * @bprm: contains the linux_binprm structure diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c index b5291ad..e127839 100644 --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -45,24 +45,30 @@ struct ima_measure_rule_entry { } lsm[MAX_LSM_RULES]; }; -/* Without LSM specific knowledge, the default policy can only be +/* + * Without LSM specific knowledge, the default policy can only be * written in terms of .action, .func, .mask, .fsmagic, and .uid */ + +/* + * The minimum rule set to allow for full TCB coverage. Measures all files + * opened or mmap for exec and everything read by root. Dangerous because + * normal users can easily run the machine out of memory simply building + * and running executables. + */ static struct ima_measure_rule_entry default_rules[] = { - {.action = DONT_MEASURE,.fsmagic = PROC_SUPER_MAGIC, - .flags = IMA_FSMAGIC}, + {.action = DONT_MEASURE,.fsmagic = PROC_SUPER_MAGIC,.flags = IMA_FSMAGIC}, {.action = DONT_MEASURE,.fsmagic = SYSFS_MAGIC,.flags = IMA_FSMAGIC}, {.action = DONT_MEASURE,.fsmagic = DEBUGFS_MAGIC,.flags = IMA_FSMAGIC}, {.action = DONT_MEASURE,.fsmagic = TMPFS_MAGIC,.flags = IMA_FSMAGIC}, - {.action = DONT_MEASURE,.fsmagic = SECURITYFS_MAGIC, - .flags = IMA_FSMAGIC}, - {.action = DONT_MEASURE,.fsmagic = 0xF97CFF8C,.flags = IMA_FSMAGIC}, + {.action = DONT_MEASURE,.fsmagic = SECURITYFS_MAGIC,.flags = IMA_FSMAGIC}, + {.action = DONT_MEASURE,.fsmagic = SELINUX_MAGIC,.flags = IMA_FSMAGIC}, {.action = MEASURE,.func = FILE_MMAP,.mask = MAY_EXEC, .flags = IMA_FUNC | IMA_MASK}, {.action = MEASURE,.func = BPRM_CHECK,.mask = MAY_EXEC, .flags = IMA_FUNC | IMA_MASK}, {.action = MEASURE,.func = PATH_CHECK,.mask = MAY_READ,.uid = 0, - .flags = IMA_FUNC | IMA_MASK | IMA_UID} + .flags = IMA_FUNC | IMA_MASK | IMA_UID}, }; static LIST_HEAD(measure_default_rules); @@ -71,6 +77,14 @@ static struct list_head *ima_measure; static DEFINE_MUTEX(ima_measure_mutex); +static bool ima_use_tcb __initdata; +static int __init default_policy_setup(char *str) +{ + ima_use_tcb = 1; + return 1; +} +__setup("ima_tcb", default_policy_setup); + /** * ima_match_rules - determine whether an inode matches the measure rule. * @rule: a pointer to a rule @@ -96,7 +110,7 @@ static bool ima_match_rules(struct ima_measure_rule_entry *rule, if ((rule->flags & IMA_UID) && rule->uid != tsk->cred->uid) return false; for (i = 0; i < MAX_LSM_RULES; i++) { - int rc; + int rc = 0; u32 osid, sid; if (!rule->lsm[i].rule) @@ -109,7 +123,7 @@ static bool ima_match_rules(struct ima_measure_rule_entry *rule, security_inode_getsecid(inode, &osid); rc = security_filter_rule_match(osid, rule->lsm[i].type, - AUDIT_EQUAL, + Audit_equal, rule->lsm[i].rule, NULL); break; @@ -119,7 +133,7 @@ static bool ima_match_rules(struct ima_measure_rule_entry *rule, security_task_getsecid(tsk, &sid); rc = security_filter_rule_match(sid, rule->lsm[i].type, - AUDIT_EQUAL, + Audit_equal, rule->lsm[i].rule, NULL); default: @@ -164,11 +178,17 @@ int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask) * ima_measure points to either the measure_default_rules or the * the new measure_policy_rules. */ -void ima_init_policy(void) +void __init ima_init_policy(void) { - int i; + int i, entries; + + /* if !ima_use_tcb set entries = 0 so we load NO default rules */ + if (ima_use_tcb) + entries = ARRAY_SIZE(default_rules); + else + entries = 0; - for (i = 0; i < ARRAY_SIZE(default_rules); i++) + for (i = 0; i < entries; i++) list_add_tail(&default_rules[i].list, &measure_default_rules); ima_measure = &measure_default_rules; } @@ -227,7 +247,7 @@ static int ima_lsm_rule_init(struct ima_measure_rule_entry *entry, entry->lsm[lsm_rule].type = audit_type; result = security_filter_rule_init(entry->lsm[lsm_rule].type, - AUDIT_EQUAL, args, + Audit_equal, args, &entry->lsm[lsm_rule].rule); return result; } diff --git a/security/lsm_audit.c b/security/lsm_audit.c new file mode 100644 index 0000000..94b8684 --- /dev/null +++ b/security/lsm_audit.c @@ -0,0 +1,386 @@ +/* + * common LSM auditing functions + * + * Based on code written for SELinux by : + * Stephen Smalley, <sds@epoch.ncsc.mil> + * James Morris <jmorris@redhat.com> + * Author : Etienne Basset, <etienne.basset@ensta.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2, + * as published by the Free Software Foundation. + */ + +#include <linux/types.h> +#include <linux/stddef.h> +#include <linux/kernel.h> +#include <linux/fs.h> +#include <linux/init.h> +#include <net/sock.h> +#include <linux/un.h> +#include <net/af_unix.h> +#include <linux/audit.h> +#include <linux/ipv6.h> +#include <linux/ip.h> +#include <net/ip.h> +#include <net/ipv6.h> +#include <linux/tcp.h> +#include <linux/udp.h> +#include <linux/dccp.h> +#include <linux/sctp.h> +#include <linux/lsm_audit.h> + +/** + * ipv4_skb_to_auditdata : fill auditdata from skb + * @skb : the skb + * @ad : the audit data to fill + * @proto : the layer 4 protocol + * + * return 0 on success + */ +int ipv4_skb_to_auditdata(struct sk_buff *skb, + struct common_audit_data *ad, u8 *proto) +{ + int ret = 0; + struct iphdr *ih; + + ih = ip_hdr(skb); + if (ih == NULL) + return -EINVAL; + + ad->u.net.v4info.saddr = ih->saddr; + ad->u.net.v4info.daddr = ih->daddr; + + if (proto) + *proto = ih->protocol; + /* non initial fragment */ + if (ntohs(ih->frag_off) & IP_OFFSET) + return 0; + + switch (ih->protocol) { + case IPPROTO_TCP: { + struct tcphdr *th = tcp_hdr(skb); + if (th == NULL) + break; + + ad->u.net.sport = th->source; + ad->u.net.dport = th->dest; + break; + } + case IPPROTO_UDP: { + struct udphdr *uh = udp_hdr(skb); + if (uh == NULL) + break; + + ad->u.net.sport = uh->source; + ad->u.net.dport = uh->dest; + break; + } + case IPPROTO_DCCP: { + struct dccp_hdr *dh = dccp_hdr(skb); + if (dh == NULL) + break; + + ad->u.net.sport = dh->dccph_sport; + ad->u.net.dport = dh->dccph_dport; + break; + } + case IPPROTO_SCTP: { + struct sctphdr *sh = sctp_hdr(skb); + if (sh == NULL) + break; + ad->u.net.sport = sh->source; + ad->u.net.dport = sh->dest; + break; + } + default: + ret = -EINVAL; + } + return ret; +} +#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) +/** + * ipv6_skb_to_auditdata : fill auditdata from skb + * @skb : the skb + * @ad : the audit data to fill + * @proto : the layer 4 protocol + * + * return 0 on success + */ +int ipv6_skb_to_auditdata(struct sk_buff *skb, + struct common_audit_data *ad, u8 *proto) +{ + int offset, ret = 0; + struct ipv6hdr *ip6; + u8 nexthdr; + + ip6 = ipv6_hdr(skb); + if (ip6 == NULL) + return -EINVAL; + ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr); + ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr); + ret = 0; + /* IPv6 can have several extension header before the Transport header + * skip them */ + offset = skb_network_offset(skb); + offset += sizeof(*ip6); + nexthdr = ip6->nexthdr; + offset = ipv6_skip_exthdr(skb, offset, &nexthdr); + if (offset < 0) + return 0; + if (proto) + *proto = nexthdr; + switch (nexthdr) { + case IPPROTO_TCP: { + struct tcphdr _tcph, *th; + + th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); + if (th == NULL) + break; + + ad->u.net.sport = th->source; + ad->u.net.dport = th->dest; + break; + } + case IPPROTO_UDP: { + struct udphdr _udph, *uh; + + uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); + if (uh == NULL) + break; + + ad->u.net.sport = uh->source; + ad->u.net.dport = uh->dest; + break; + } + case IPPROTO_DCCP: { + struct dccp_hdr _dccph, *dh; + + dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); + if (dh == NULL) + break; + + ad->u.net.sport = dh->dccph_sport; + ad->u.net.dport = dh->dccph_dport; + break; + } + case IPPROTO_SCTP: { + struct sctphdr _sctph, *sh; + + sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); + if (sh == NULL) + break; + ad->u.net.sport = sh->source; + ad->u.net.dport = sh->dest; + break; + } + default: + ret = -EINVAL; + } + return ret; +} +#endif + + +static inline void print_ipv6_addr(struct audit_buffer *ab, + struct in6_addr *addr, __be16 port, + char *name1, char *name2) +{ + if (!ipv6_addr_any(addr)) + audit_log_format(ab, " %s=%pI6", name1, addr); + if (port) + audit_log_format(ab, " %s=%d", name2, ntohs(port)); +} + +static inline void print_ipv4_addr(struct audit_buffer *ab, __be32 addr, + __be16 port, char *name1, char *name2) +{ + if (addr) + audit_log_format(ab, " %s=%pI4", name1, &addr); + if (port) + audit_log_format(ab, " %s=%d", name2, ntohs(port)); +} + +/** + * dump_common_audit_data - helper to dump common audit data + * @a : common audit data + * + */ +static void dump_common_audit_data(struct audit_buffer *ab, + struct common_audit_data *a) +{ + struct inode *inode = NULL; + struct task_struct *tsk = current; + + if (a->tsk) + tsk = a->tsk; + if (tsk && tsk->pid) { + audit_log_format(ab, " pid=%d comm=", tsk->pid); + audit_log_untrustedstring(ab, tsk->comm); + } + + switch (a->type) { + case LSM_AUDIT_DATA_IPC: + audit_log_format(ab, " key=%d ", a->u.ipc_id); + break; + case LSM_AUDIT_DATA_CAP: + audit_log_format(ab, " capability=%d ", a->u.cap); + break; + case LSM_AUDIT_DATA_FS: + if (a->u.fs.path.dentry) { + struct dentry *dentry = a->u.fs.path.dentry; + if (a->u.fs.path.mnt) { + audit_log_d_path(ab, "path=", &a->u.fs.path); + } else { + audit_log_format(ab, " name="); + audit_log_untrustedstring(ab, + dentry->d_name.name); + } + inode = dentry->d_inode; + } else if (a->u.fs.inode) { + struct dentry *dentry; + inode = a->u.fs.inode; + dentry = d_find_alias(inode); + if (dentry) { + audit_log_format(ab, " name="); + audit_log_untrustedstring(ab, + dentry->d_name.name); + dput(dentry); + } + } + if (inode) + audit_log_format(ab, " dev=%s ino=%lu", + inode->i_sb->s_id, + inode->i_ino); + break; + case LSM_AUDIT_DATA_TASK: + tsk = a->u.tsk; + if (tsk && tsk->pid) { + audit_log_format(ab, " pid=%d comm=", tsk->pid); + audit_log_untrustedstring(ab, tsk->comm); + } + break; + case LSM_AUDIT_DATA_NET: + if (a->u.net.sk) { + struct sock *sk = a->u.net.sk; + struct unix_sock *u; + int len = 0; + char *p = NULL; + + switch (sk->sk_family) { + case AF_INET: { + struct inet_sock *inet = inet_sk(sk); + + print_ipv4_addr(ab, inet->rcv_saddr, + inet->sport, + "laddr", "lport"); + print_ipv4_addr(ab, inet->daddr, + inet->dport, + "faddr", "fport"); + break; + } + case AF_INET6: { + struct inet_sock *inet = inet_sk(sk); + struct ipv6_pinfo *inet6 = inet6_sk(sk); + + print_ipv6_addr(ab, &inet6->rcv_saddr, + inet->sport, + "laddr", "lport"); + print_ipv6_addr(ab, &inet6->daddr, + inet->dport, + "faddr", "fport"); + break; + } + case AF_UNIX: + u = unix_sk(sk); + if (u->dentry) { + struct path path = { + .dentry = u->dentry, + .mnt = u->mnt + }; + audit_log_d_path(ab, "path=", &path); + break; + } + if (!u->addr) + break; + len = u->addr->len-sizeof(short); + p = &u->addr->name->sun_path[0]; + audit_log_format(ab, " path="); + if (*p) + audit_log_untrustedstring(ab, p); + else + audit_log_n_hex(ab, p, len); + break; + } + } + + switch (a->u.net.family) { + case AF_INET: + print_ipv4_addr(ab, a->u.net.v4info.saddr, + a->u.net.sport, + "saddr", "src"); + print_ipv4_addr(ab, a->u.net.v4info.daddr, + a->u.net.dport, + "daddr", "dest"); + break; + case AF_INET6: + print_ipv6_addr(ab, &a->u.net.v6info.saddr, + a->u.net.sport, + "saddr", "src"); + print_ipv6_addr(ab, &a->u.net.v6info.daddr, + a->u.net.dport, + "daddr", "dest"); + break; + } + if (a->u.net.netif > 0) { + struct net_device *dev; + + /* NOTE: we always use init's namespace */ + dev = dev_get_by_index(&init_net, a->u.net.netif); + if (dev) { + audit_log_format(ab, " netif=%s", dev->name); + dev_put(dev); + } + } + break; +#ifdef CONFIG_KEYS + case LSM_AUDIT_DATA_KEY: + audit_log_format(ab, " key_serial=%u", a->u.key_struct.key); + if (a->u.key_struct.key_desc) { + audit_log_format(ab, " key_desc="); + audit_log_untrustedstring(ab, a->u.key_struct.key_desc); + } + break; +#endif + } /* switch (a->type) */ +} + +/** + * common_lsm_audit - generic LSM auditing function + * @a: auxiliary audit data + * + * setup the audit buffer for common security information + * uses callback to print LSM specific information + */ +void common_lsm_audit(struct common_audit_data *a) +{ + struct audit_buffer *ab; + + if (a == NULL) + return; + /* we use GFP_ATOMIC so we won't sleep */ + ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_AVC); + + if (ab == NULL) + return; + + if (a->lsm_pre_audit) + a->lsm_pre_audit(ab, a); + + dump_common_audit_data(ab, a); + + if (a->lsm_post_audit) + a->lsm_post_audit(ab, a); + + audit_log_end(ab); +} diff --git a/security/root_plug.c b/security/root_plug.c index 40fb4f1..2f7ffa6 100644 --- a/security/root_plug.c +++ b/security/root_plug.c @@ -71,18 +71,6 @@ static int rootplug_bprm_check_security (struct linux_binprm *bprm) } static struct security_operations rootplug_security_ops = { - /* Use the capability functions for some of the hooks */ - .ptrace_may_access = cap_ptrace_may_access, - .ptrace_traceme = cap_ptrace_traceme, - .capget = cap_capget, - .capset = cap_capset, - .capable = cap_capable, - - .bprm_set_creds = cap_bprm_set_creds, - - .task_fix_setuid = cap_task_fix_setuid, - .task_prctl = cap_task_prctl, - .bprm_check_security = rootplug_bprm_check_security, }; diff --git a/security/security.c b/security/security.c index 5284255..dc7674f 100644 --- a/security/security.c +++ b/security/security.c @@ -26,9 +26,6 @@ extern void security_fixup_ops(struct security_operations *ops); struct security_operations *security_ops; /* Initialized to NULL */ -/* amount of vm to protect from userspace access */ -unsigned long mmap_min_addr = CONFIG_SECURITY_DEFAULT_MMAP_MIN_ADDR; - static inline int verify(struct security_operations *ops) { /* verify the security_operations structure exists */ diff --git a/security/selinux/avc.c b/security/selinux/avc.c index 7f9b5fa..b2ab608 100644 --- a/security/selinux/avc.c +++ b/security/selinux/avc.c @@ -927,7 +927,7 @@ int avc_has_perm_noaudit(u32 ssid, u32 tsid, if (denied) { if (flags & AVC_STRICT) rc = -EACCES; - else if (!selinux_enforcing || security_permissive_sid(ssid)) + else if (!selinux_enforcing || (avd->flags & AVD_FLAGS_PERMISSIVE)) avc_update_node(AVC_CALLBACK_GRANT, requested, ssid, tsid, tclass, avd->seqno); else diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 2fcad7c..195906b 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -1980,10 +1980,6 @@ static int selinux_sysctl(ctl_table *table, int op) u32 tsid, sid; int rc; - rc = secondary_ops->sysctl(table, op); - if (rc) - return rc; - sid = current_sid(); rc = selinux_sysctl_get_sid(table, (op == 0001) ? @@ -2375,10 +2371,8 @@ static void selinux_bprm_committed_creds(struct linux_binprm *bprm) { const struct task_security_struct *tsec = current_security(); struct itimerval itimer; - struct sighand_struct *psig; u32 osid, sid; int rc, i; - unsigned long flags; osid = tsec->osid; sid = tsec->sid; @@ -2398,22 +2392,20 @@ static void selinux_bprm_committed_creds(struct linux_binprm *bprm) memset(&itimer, 0, sizeof itimer); for (i = 0; i < 3; i++) do_setitimer(i, &itimer, NULL); - flush_signals(current); spin_lock_irq(¤t->sighand->siglock); - flush_signal_handlers(current, 1); - sigemptyset(¤t->blocked); - recalc_sigpending(); + if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) { + __flush_signals(current); + flush_signal_handlers(current, 1); + sigemptyset(¤t->blocked); + } spin_unlock_irq(¤t->sighand->siglock); } /* Wake up the parent if it is waiting so that it can recheck * wait permission to the new task SID. */ - read_lock_irq(&tasklist_lock); - psig = current->parent->sighand; - spin_lock_irqsave(&psig->siglock, flags); - wake_up_interruptible(¤t->parent->signal->wait_chldexit); - spin_unlock_irqrestore(&psig->siglock, flags); - read_unlock_irq(&tasklist_lock); + read_lock(&tasklist_lock); + wake_up_interruptible(¤t->real_parent->signal->wait_chldexit); + read_unlock(&tasklist_lock); } /* superblock security operations */ diff --git a/security/selinux/include/security.h b/security/selinux/include/security.h index 5c3434f..ca83579 100644 --- a/security/selinux/include/security.h +++ b/security/selinux/include/security.h @@ -8,14 +8,13 @@ #ifndef _SELINUX_SECURITY_H_ #define _SELINUX_SECURITY_H_ +#include <linux/magic.h> #include "flask.h" #define SECSID_NULL 0x00000000 /* unspecified SID */ #define SECSID_WILD 0xffffffff /* wildcard SID */ #define SECCLASS_NULL 0x0000 /* no class */ -#define SELINUX_MAGIC 0xf97cff8c - /* Identify specific policy version changes */ #define POLICYDB_VERSION_BASE 15 #define POLICYDB_VERSION_BOOL 16 @@ -91,9 +90,11 @@ struct av_decision { u32 auditallow; u32 auditdeny; u32 seqno; + u32 flags; }; -int security_permissive_sid(u32 sid); +/* definitions of av_decision.flags */ +#define AVD_FLAGS_PERMISSIVE 0x0001 int security_compute_av(u32 ssid, u32 tsid, u16 tclass, u32 requested, diff --git a/security/selinux/nlmsgtab.c b/security/selinux/nlmsgtab.c index c6875fd..dd7cc6d 100644 --- a/security/selinux/nlmsgtab.c +++ b/security/selinux/nlmsgtab.c @@ -112,6 +112,8 @@ static struct nlmsg_perm nlmsg_audit_perms[] = { AUDIT_DEL_RULE, NETLINK_AUDIT_SOCKET__NLMSG_WRITE }, { AUDIT_USER, NETLINK_AUDIT_SOCKET__NLMSG_RELAY }, { AUDIT_SIGNAL_INFO, NETLINK_AUDIT_SOCKET__NLMSG_READ }, + { AUDIT_TRIM, NETLINK_AUDIT_SOCKET__NLMSG_WRITE }, + { AUDIT_MAKE_EQUIV, NETLINK_AUDIT_SOCKET__NLMSG_WRITE }, { AUDIT_TTY_GET, NETLINK_AUDIT_SOCKET__NLMSG_READ }, { AUDIT_TTY_SET, NETLINK_AUDIT_SOCKET__NLMSG_TTY_AUDIT }, }; diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c index 2d5136e..b4fc506 100644 --- a/security/selinux/selinuxfs.c +++ b/security/selinux/selinuxfs.c @@ -527,10 +527,10 @@ static ssize_t sel_write_access(struct file *file, char *buf, size_t size) goto out2; length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, - "%x %x %x %x %u", + "%x %x %x %x %u %x", avd.allowed, 0xffffffff, avd.auditallow, avd.auditdeny, - avd.seqno); + avd.seqno, avd.flags); out2: kfree(tcon); out: @@ -803,10 +803,6 @@ static ssize_t sel_read_bool(struct file *filep, char __user *buf, goto out; } - if (count > PAGE_SIZE) { - ret = -EINVAL; - goto out; - } page = (char *)get_zeroed_page(GFP_KERNEL); if (!page) { ret = -ENOMEM; diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c index deeec6c..500e6f7 100644 --- a/security/selinux/ss/services.c +++ b/security/selinux/ss/services.c @@ -410,6 +410,7 @@ static int context_struct_compute_av(struct context *scontext, avd->auditallow = 0; avd->auditdeny = 0xffffffff; avd->seqno = latest_granting; + avd->flags = 0; /* * Check for all the invalid cases. @@ -528,31 +529,6 @@ inval_class: return 0; } -/* - * Given a sid find if the type has the permissive flag set - */ -int security_permissive_sid(u32 sid) -{ - struct context *context; - u32 type; - int rc; - - read_lock(&policy_rwlock); - - context = sidtab_search(&sidtab, sid); - BUG_ON(!context); - - type = context->type; - /* - * we are intentionally using type here, not type-1, the 0th bit may - * someday indicate that we are globally setting permissive in policy. - */ - rc = ebitmap_get_bit(&policydb.permissive_map, type); - - read_unlock(&policy_rwlock); - return rc; -} - static int security_validtrans_handle_fail(struct context *ocontext, struct context *ncontext, struct context *tcontext, @@ -767,6 +743,10 @@ int security_compute_av(u32 ssid, rc = context_struct_compute_av(scontext, tcontext, tclass, requested, avd); + + /* permissive domain? */ + if (ebitmap_get_bit(&policydb.permissive_map, scontext->type)) + avd->flags |= AVD_FLAGS_PERMISSIVE; out: read_unlock(&policy_rwlock); return rc; diff --git a/security/smack/smack.h b/security/smack/smack.h index 42ef313..243bec1 100644 --- a/security/smack/smack.h +++ b/security/smack/smack.h @@ -20,6 +20,7 @@ #include <net/netlabel.h> #include <linux/list.h> #include <linux/rculist.h> +#include <linux/lsm_audit.h> /* * Why 23? CIPSO is constrained to 30, so a 32 byte buffer is @@ -179,6 +180,20 @@ struct smack_known { #define MAY_NOT 0 /* + * Number of access types used by Smack (rwxa) + */ +#define SMK_NUM_ACCESS_TYPE 4 + +/* + * Smack audit data; is empty if CONFIG_AUDIT not set + * to save some stack + */ +struct smk_audit_info { +#ifdef CONFIG_AUDIT + struct common_audit_data a; +#endif +}; +/* * These functions are in smack_lsm.c */ struct inode_smack *new_inode_smack(char *); @@ -186,8 +201,8 @@ struct inode_smack *new_inode_smack(char *); /* * These functions are in smack_access.c */ -int smk_access(char *, char *, int); -int smk_curacc(char *, u32); +int smk_access(char *, char *, int, struct smk_audit_info *); +int smk_curacc(char *, u32, struct smk_audit_info *); int smack_to_cipso(const char *, struct smack_cipso *); void smack_from_cipso(u32, char *, char *); char *smack_from_secid(const u32); @@ -237,4 +252,93 @@ static inline char *smk_of_inode(const struct inode *isp) return sip->smk_inode; } +/* + * logging functions + */ +#define SMACK_AUDIT_DENIED 0x1 +#define SMACK_AUDIT_ACCEPT 0x2 +extern int log_policy; + +void smack_log(char *subject_label, char *object_label, + int request, + int result, struct smk_audit_info *auditdata); + +#ifdef CONFIG_AUDIT + +/* + * some inline functions to set up audit data + * they do nothing if CONFIG_AUDIT is not set + * + */ +static inline void smk_ad_init(struct smk_audit_info *a, const char *func, + char type) +{ + memset(a, 0, sizeof(*a)); + a->a.type = type; + a->a.function = func; +} + +static inline void smk_ad_setfield_u_tsk(struct smk_audit_info *a, + struct task_struct *t) +{ + a->a.u.tsk = t; +} +static inline void smk_ad_setfield_u_fs_path_dentry(struct smk_audit_info *a, + struct dentry *d) +{ + a->a.u.fs.path.dentry = d; +} +static inline void smk_ad_setfield_u_fs_path_mnt(struct smk_audit_info *a, + struct vfsmount *m) +{ + a->a.u.fs.path.mnt = m; +} +static inline void smk_ad_setfield_u_fs_inode(struct smk_audit_info *a, + struct inode *i) +{ + a->a.u.fs.inode = i; +} +static inline void smk_ad_setfield_u_fs_path(struct smk_audit_info *a, + struct path p) +{ + a->a.u.fs.path = p; +} +static inline void smk_ad_setfield_u_net_sk(struct smk_audit_info *a, + struct sock *sk) +{ + a->a.u.net.sk = sk; +} + +#else /* no AUDIT */ + +static inline void smk_ad_init(struct smk_audit_info *a, const char *func, + char type) +{ +} +static inline void smk_ad_setfield_u_tsk(struct smk_audit_info *a, + struct task_struct *t) +{ +} +static inline void smk_ad_setfield_u_fs_path_dentry(struct smk_audit_info *a, + struct dentry *d) +{ +} +static inline void smk_ad_setfield_u_fs_path_mnt(struct smk_audit_info *a, + struct vfsmount *m) +{ +} +static inline void smk_ad_setfield_u_fs_inode(struct smk_audit_info *a, + struct inode *i) +{ +} +static inline void smk_ad_setfield_u_fs_path(struct smk_audit_info *a, + struct path p) +{ +} +static inline void smk_ad_setfield_u_net_sk(struct smk_audit_info *a, + struct sock *sk) +{ +} +#endif + #endif /* _SECURITY_SMACK_H */ diff --git a/security/smack/smack_access.c b/security/smack/smack_access.c index ac0a270..513dc1a 100644 --- a/security/smack/smack_access.c +++ b/security/smack/smack_access.c @@ -59,11 +59,18 @@ LIST_HEAD(smack_known_list); */ static u32 smack_next_secid = 10; +/* + * what events do we log + * can be overwritten at run-time by /smack/logging + */ +int log_policy = SMACK_AUDIT_DENIED; + /** * smk_access - determine if a subject has a specific access to an object * @subject_label: a pointer to the subject's Smack label * @object_label: a pointer to the object's Smack label * @request: the access requested, in "MAY" format + * @a : a pointer to the audit data * * This function looks up the subject/object pair in the * access rule list and returns 0 if the access is permitted, @@ -78,10 +85,12 @@ static u32 smack_next_secid = 10; * will be on the list, so checking the pointers may be a worthwhile * optimization. */ -int smk_access(char *subject_label, char *object_label, int request) +int smk_access(char *subject_label, char *object_label, int request, + struct smk_audit_info *a) { u32 may = MAY_NOT; struct smack_rule *srp; + int rc = 0; /* * Hardcoded comparisons. @@ -89,8 +98,10 @@ int smk_access(char *subject_label, char *object_label, int request) * A star subject can't access any object. */ if (subject_label == smack_known_star.smk_known || - strcmp(subject_label, smack_known_star.smk_known) == 0) - return -EACCES; + strcmp(subject_label, smack_known_star.smk_known) == 0) { + rc = -EACCES; + goto out_audit; + } /* * An internet object can be accessed by any subject. * Tasks cannot be assigned the internet label. @@ -100,20 +111,20 @@ int smk_access(char *subject_label, char *object_label, int request) subject_label == smack_known_web.smk_known || strcmp(object_label, smack_known_web.smk_known) == 0 || strcmp(subject_label, smack_known_web.smk_known) == 0) - return 0; + goto out_audit; /* * A star object can be accessed by any subject. */ if (object_label == smack_known_star.smk_known || strcmp(object_label, smack_known_star.smk_known) == 0) - return 0; + goto out_audit; /* * An object can be accessed in any way by a subject * with the same label. */ if (subject_label == object_label || strcmp(subject_label, object_label) == 0) - return 0; + goto out_audit; /* * A hat subject can read any object. * A floor object can be read by any subject. @@ -121,10 +132,10 @@ int smk_access(char *subject_label, char *object_label, int request) if ((request & MAY_ANYREAD) == request) { if (object_label == smack_known_floor.smk_known || strcmp(object_label, smack_known_floor.smk_known) == 0) - return 0; + goto out_audit; if (subject_label == smack_known_hat.smk_known || strcmp(subject_label, smack_known_hat.smk_known) == 0) - return 0; + goto out_audit; } /* * Beyond here an explicit relationship is required. @@ -148,28 +159,36 @@ int smk_access(char *subject_label, char *object_label, int request) * This is a bit map operation. */ if ((request & may) == request) - return 0; - - return -EACCES; + goto out_audit; + + rc = -EACCES; +out_audit: +#ifdef CONFIG_AUDIT + if (a) + smack_log(subject_label, object_label, request, rc, a); +#endif + return rc; } /** * smk_curacc - determine if current has a specific access to an object * @obj_label: a pointer to the object's Smack label * @mode: the access requested, in "MAY" format + * @a : common audit data * * This function checks the current subject label/object label pair * in the access rule list and returns 0 if the access is permitted, * non zero otherwise. It allows that current may have the capability * to override the rules. */ -int smk_curacc(char *obj_label, u32 mode) +int smk_curacc(char *obj_label, u32 mode, struct smk_audit_info *a) { int rc; + char *sp = current_security(); - rc = smk_access(current_security(), obj_label, mode); + rc = smk_access(sp, obj_label, mode, NULL); if (rc == 0) - return 0; + goto out_audit; /* * Return if a specific label has been designated as the @@ -177,14 +196,105 @@ int smk_curacc(char *obj_label, u32 mode) * have that label. */ if (smack_onlycap != NULL && smack_onlycap != current->cred->security) - return rc; + goto out_audit; if (capable(CAP_MAC_OVERRIDE)) return 0; +out_audit: +#ifdef CONFIG_AUDIT + if (a) + smack_log(sp, obj_label, mode, rc, a); +#endif return rc; } +#ifdef CONFIG_AUDIT +/** + * smack_str_from_perm : helper to transalate an int to a + * readable string + * @string : the string to fill + * @access : the int + * + */ +static inline void smack_str_from_perm(char *string, int access) +{ + int i = 0; + if (access & MAY_READ) + string[i++] = 'r'; + if (access & MAY_WRITE) + string[i++] = 'w'; + if (access & MAY_EXEC) + string[i++] = 'x'; + if (access & MAY_APPEND) + string[i++] = 'a'; + string[i] = '\0'; +} +/** + * smack_log_callback - SMACK specific information + * will be called by generic audit code + * @ab : the audit_buffer + * @a : audit_data + * + */ +static void smack_log_callback(struct audit_buffer *ab, void *a) +{ + struct common_audit_data *ad = a; + struct smack_audit_data *sad = &ad->lsm_priv.smack_audit_data; + audit_log_format(ab, "lsm=SMACK fn=%s action=%s", ad->function, + sad->result ? "denied" : "granted"); + audit_log_format(ab, " subject="); + audit_log_untrustedstring(ab, sad->subject); + audit_log_format(ab, " object="); + audit_log_untrustedstring(ab, sad->object); + audit_log_format(ab, " requested=%s", sad->request); +} + +/** + * smack_log - Audit the granting or denial of permissions. + * @subject_label : smack label of the requester + * @object_label : smack label of the object being accessed + * @request: requested permissions + * @result: result from smk_access + * @a: auxiliary audit data + * + * Audit the granting or denial of permissions in accordance + * with the policy. + */ +void smack_log(char *subject_label, char *object_label, int request, + int result, struct smk_audit_info *ad) +{ + char request_buffer[SMK_NUM_ACCESS_TYPE + 1]; + struct smack_audit_data *sad; + struct common_audit_data *a = &ad->a; + + /* check if we have to log the current event */ + if (result != 0 && (log_policy & SMACK_AUDIT_DENIED) == 0) + return; + if (result == 0 && (log_policy & SMACK_AUDIT_ACCEPT) == 0) + return; + + if (a->function == NULL) + a->function = "unknown"; + + /* end preparing the audit data */ + sad = &a->lsm_priv.smack_audit_data; + smack_str_from_perm(request_buffer, request); + sad->subject = subject_label; + sad->object = object_label; + sad->request = request_buffer; + sad->result = result; + a->lsm_pre_audit = smack_log_callback; + + common_lsm_audit(a); +} +#else /* #ifdef CONFIG_AUDIT */ +void smack_log(char *subject_label, char *object_label, int request, + int result, struct smk_audit_info *ad) +{ +} +#endif + static DEFINE_MUTEX(smack_known_lock); /** @@ -209,7 +319,8 @@ struct smack_known *smk_import_entry(const char *string, int len) if (found) smack[i] = '\0'; else if (i >= len || string[i] > '~' || string[i] <= ' ' || - string[i] == '/') { + string[i] == '/' || string[i] == '"' || + string[i] == '\\' || string[i] == '\'') { smack[i] = '\0'; found = 1; } else diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index 98b3195..0023182 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -30,7 +30,6 @@ #include <net/netlabel.h> #include <net/cipso_ipv4.h> #include <linux/audit.h> - #include "smack.h" #define task_security(task) (task_cred_xxx((task), security)) @@ -103,14 +102,24 @@ struct inode_smack *new_inode_smack(char *smack) static int smack_ptrace_may_access(struct task_struct *ctp, unsigned int mode) { int rc; + struct smk_audit_info ad; + char *sp, *tsp; rc = cap_ptrace_may_access(ctp, mode); if (rc != 0) return rc; - rc = smk_access(current_security(), task_security(ctp), MAY_READWRITE); + sp = current_security(); + tsp = task_security(ctp); + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK); + smk_ad_setfield_u_tsk(&ad, ctp); + + /* we won't log here, because rc can be overriden */ + rc = smk_access(sp, tsp, MAY_READWRITE, NULL); if (rc != 0 && capable(CAP_MAC_OVERRIDE)) - return 0; + rc = 0; + + smack_log(sp, tsp, MAY_READWRITE, rc, &ad); return rc; } @@ -125,14 +134,24 @@ static int smack_ptrace_may_access(struct task_struct *ctp, unsigned int mode) static int smack_ptrace_traceme(struct task_struct *ptp) { int rc; + struct smk_audit_info ad; + char *sp, *tsp; rc = cap_ptrace_traceme(ptp); if (rc != 0) return rc; - rc = smk_access(task_security(ptp), current_security(), MAY_READWRITE); + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK); + smk_ad_setfield_u_tsk(&ad, ptp); + + sp = current_security(); + tsp = task_security(ptp); + /* we won't log here, because rc can be overriden */ + rc = smk_access(tsp, sp, MAY_READWRITE, NULL); if (rc != 0 && has_capability(ptp, CAP_MAC_OVERRIDE)) - return 0; + rc = 0; + + smack_log(tsp, sp, MAY_READWRITE, rc, &ad); return rc; } @@ -327,8 +346,14 @@ static int smack_sb_kern_mount(struct super_block *sb, int flags, void *data) static int smack_sb_statfs(struct dentry *dentry) { struct superblock_smack *sbp = dentry->d_sb->s_security; + int rc; + struct smk_audit_info ad; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path_dentry(&ad, dentry); - return smk_curacc(sbp->smk_floor, MAY_READ); + rc = smk_curacc(sbp->smk_floor, MAY_READ, &ad); + return rc; } /** @@ -346,8 +371,12 @@ static int smack_sb_mount(char *dev_name, struct path *path, char *type, unsigned long flags, void *data) { struct superblock_smack *sbp = path->mnt->mnt_sb->s_security; + struct smk_audit_info ad; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path(&ad, *path); - return smk_curacc(sbp->smk_floor, MAY_WRITE); + return smk_curacc(sbp->smk_floor, MAY_WRITE, &ad); } /** @@ -361,10 +390,14 @@ static int smack_sb_mount(char *dev_name, struct path *path, static int smack_sb_umount(struct vfsmount *mnt, int flags) { struct superblock_smack *sbp; + struct smk_audit_info ad; - sbp = mnt->mnt_sb->s_security; + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path_dentry(&ad, mnt->mnt_mountpoint); + smk_ad_setfield_u_fs_path_mnt(&ad, mnt); - return smk_curacc(sbp->smk_floor, MAY_WRITE); + sbp = mnt->mnt_sb->s_security; + return smk_curacc(sbp->smk_floor, MAY_WRITE, &ad); } /* @@ -441,15 +474,20 @@ static int smack_inode_init_security(struct inode *inode, struct inode *dir, static int smack_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) { - int rc; char *isp; + struct smk_audit_info ad; + int rc; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry); isp = smk_of_inode(old_dentry->d_inode); - rc = smk_curacc(isp, MAY_WRITE); + rc = smk_curacc(isp, MAY_WRITE, &ad); if (rc == 0 && new_dentry->d_inode != NULL) { isp = smk_of_inode(new_dentry->d_inode); - rc = smk_curacc(isp, MAY_WRITE); + smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry); + rc = smk_curacc(isp, MAY_WRITE, &ad); } return rc; @@ -466,18 +504,24 @@ static int smack_inode_link(struct dentry *old_dentry, struct inode *dir, static int smack_inode_unlink(struct inode *dir, struct dentry *dentry) { struct inode *ip = dentry->d_inode; + struct smk_audit_info ad; int rc; + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path_dentry(&ad, dentry); + /* * You need write access to the thing you're unlinking */ - rc = smk_curacc(smk_of_inode(ip), MAY_WRITE); - if (rc == 0) + rc = smk_curacc(smk_of_inode(ip), MAY_WRITE, &ad); + if (rc == 0) { /* * You also need write access to the containing directory */ - rc = smk_curacc(smk_of_inode(dir), MAY_WRITE); - + smk_ad_setfield_u_fs_path_dentry(&ad, NULL); + smk_ad_setfield_u_fs_inode(&ad, dir); + rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad); + } return rc; } @@ -491,17 +535,24 @@ static int smack_inode_unlink(struct inode *dir, struct dentry *dentry) */ static int smack_inode_rmdir(struct inode *dir, struct dentry *dentry) { + struct smk_audit_info ad; int rc; + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path_dentry(&ad, dentry); + /* * You need write access to the thing you're removing */ - rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE); - if (rc == 0) + rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad); + if (rc == 0) { /* * You also need write access to the containing directory */ - rc = smk_curacc(smk_of_inode(dir), MAY_WRITE); + smk_ad_setfield_u_fs_path_dentry(&ad, NULL); + smk_ad_setfield_u_fs_inode(&ad, dir); + rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad); + } return rc; } @@ -525,15 +576,19 @@ static int smack_inode_rename(struct inode *old_inode, { int rc; char *isp; + struct smk_audit_info ad; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry); isp = smk_of_inode(old_dentry->d_inode); - rc = smk_curacc(isp, MAY_READWRITE); + rc = smk_curacc(isp, MAY_READWRITE, &ad); if (rc == 0 && new_dentry->d_inode != NULL) { isp = smk_of_inode(new_dentry->d_inode); - rc = smk_curacc(isp, MAY_READWRITE); + smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry); + rc = smk_curacc(isp, MAY_READWRITE, &ad); } - return rc; } @@ -548,13 +603,15 @@ static int smack_inode_rename(struct inode *old_inode, */ static int smack_inode_permission(struct inode *inode, int mask) { + struct smk_audit_info ad; /* * No permission to check. Existence test. Yup, it's there. */ if (mask == 0) return 0; - - return smk_curacc(smk_of_inode(inode), mask); + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_inode(&ad, inode); + return smk_curacc(smk_of_inode(inode), mask, &ad); } /** @@ -566,13 +623,16 @@ static int smack_inode_permission(struct inode *inode, int mask) */ static int smack_inode_setattr(struct dentry *dentry, struct iattr *iattr) { + struct smk_audit_info ad; /* * Need to allow for clearing the setuid bit. */ if (iattr->ia_valid & ATTR_FORCE) return 0; + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path_dentry(&ad, dentry); - return smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE); + return smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad); } /** @@ -584,7 +644,12 @@ static int smack_inode_setattr(struct dentry *dentry, struct iattr *iattr) */ static int smack_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) { - return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ); + struct smk_audit_info ad; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path_dentry(&ad, dentry); + smk_ad_setfield_u_fs_path_mnt(&ad, mnt); + return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ, &ad); } /** @@ -602,6 +667,7 @@ static int smack_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) static int smack_inode_setxattr(struct dentry *dentry, const char *name, const void *value, size_t size, int flags) { + struct smk_audit_info ad; int rc = 0; if (strcmp(name, XATTR_NAME_SMACK) == 0 || @@ -619,8 +685,11 @@ static int smack_inode_setxattr(struct dentry *dentry, const char *name, } else rc = cap_inode_setxattr(dentry, name, value, size, flags); + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path_dentry(&ad, dentry); + if (rc == 0) - rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE); + rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad); return rc; } @@ -672,7 +741,12 @@ static void smack_inode_post_setxattr(struct dentry *dentry, const char *name, */ static int smack_inode_getxattr(struct dentry *dentry, const char *name) { - return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ); + struct smk_audit_info ad; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path_dentry(&ad, dentry); + + return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ, &ad); } /* @@ -686,6 +760,7 @@ static int smack_inode_getxattr(struct dentry *dentry, const char *name) */ static int smack_inode_removexattr(struct dentry *dentry, const char *name) { + struct smk_audit_info ad; int rc = 0; if (strcmp(name, XATTR_NAME_SMACK) == 0 || @@ -696,8 +771,10 @@ static int smack_inode_removexattr(struct dentry *dentry, const char *name) } else rc = cap_inode_removexattr(dentry, name); + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path_dentry(&ad, dentry); if (rc == 0) - rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE); + rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad); return rc; } @@ -856,12 +933,16 @@ static int smack_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { int rc = 0; + struct smk_audit_info ad; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path(&ad, file->f_path); if (_IOC_DIR(cmd) & _IOC_WRITE) - rc = smk_curacc(file->f_security, MAY_WRITE); + rc = smk_curacc(file->f_security, MAY_WRITE, &ad); if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ)) - rc = smk_curacc(file->f_security, MAY_READ); + rc = smk_curacc(file->f_security, MAY_READ, &ad); return rc; } @@ -875,7 +956,11 @@ static int smack_file_ioctl(struct file *file, unsigned int cmd, */ static int smack_file_lock(struct file *file, unsigned int cmd) { - return smk_curacc(file->f_security, MAY_WRITE); + struct smk_audit_info ad; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path_dentry(&ad, file->f_path.dentry); + return smk_curacc(file->f_security, MAY_WRITE, &ad); } /** @@ -889,8 +974,12 @@ static int smack_file_lock(struct file *file, unsigned int cmd) static int smack_file_fcntl(struct file *file, unsigned int cmd, unsigned long arg) { + struct smk_audit_info ad; int rc; + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path(&ad, file->f_path); + switch (cmd) { case F_DUPFD: case F_GETFD: @@ -898,7 +987,7 @@ static int smack_file_fcntl(struct file *file, unsigned int cmd, case F_GETLK: case F_GETOWN: case F_GETSIG: - rc = smk_curacc(file->f_security, MAY_READ); + rc = smk_curacc(file->f_security, MAY_READ, &ad); break; case F_SETFD: case F_SETFL: @@ -906,10 +995,10 @@ static int smack_file_fcntl(struct file *file, unsigned int cmd, case F_SETLKW: case F_SETOWN: case F_SETSIG: - rc = smk_curacc(file->f_security, MAY_WRITE); + rc = smk_curacc(file->f_security, MAY_WRITE, &ad); break; default: - rc = smk_curacc(file->f_security, MAY_READWRITE); + rc = smk_curacc(file->f_security, MAY_READWRITE, &ad); } return rc; @@ -944,14 +1033,21 @@ static int smack_file_send_sigiotask(struct task_struct *tsk, { struct file *file; int rc; + char *tsp = tsk->cred->security; + struct smk_audit_info ad; /* * struct fown_struct is never outside the context of a struct file */ file = container_of(fown, struct file, f_owner); - rc = smk_access(file->f_security, tsk->cred->security, MAY_WRITE); + /* we don't log here as rc can be overriden */ + rc = smk_access(file->f_security, tsp, MAY_WRITE, NULL); if (rc != 0 && has_capability(tsk, CAP_MAC_OVERRIDE)) - return 0; + rc = 0; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK); + smk_ad_setfield_u_tsk(&ad, tsk); + smack_log(file->f_security, tsp, MAY_WRITE, rc, &ad); return rc; } @@ -964,7 +1060,10 @@ static int smack_file_send_sigiotask(struct task_struct *tsk, static int smack_file_receive(struct file *file) { int may = 0; + struct smk_audit_info ad; + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK); + smk_ad_setfield_u_fs_path(&ad, file->f_path); /* * This code relies on bitmasks. */ @@ -973,7 +1072,7 @@ static int smack_file_receive(struct file *file) if (file->f_mode & FMODE_WRITE) may |= MAY_WRITE; - return smk_curacc(file->f_security, may); + return smk_curacc(file->f_security, may, &ad); } /* @@ -1053,6 +1152,22 @@ static int smack_kernel_create_files_as(struct cred *new, } /** + * smk_curacc_on_task - helper to log task related access + * @p: the task object + * @access : the access requested + * + * Return 0 if access is permitted + */ +static int smk_curacc_on_task(struct task_struct *p, int access) +{ + struct smk_audit_info ad; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK); + smk_ad_setfield_u_tsk(&ad, p); + return smk_curacc(task_security(p), access, &ad); +} + +/** * smack_task_setpgid - Smack check on setting pgid * @p: the task object * @pgid: unused @@ -1061,7 +1176,7 @@ static int smack_kernel_create_files_as(struct cred *new, */ static int smack_task_setpgid(struct task_struct *p, pid_t pgid) { - return smk_curacc(task_security(p), MAY_WRITE); + return smk_curacc_on_task(p, MAY_WRITE); } /** @@ -1072,7 +1187,7 @@ static int smack_task_setpgid(struct task_struct *p, pid_t pgid) */ static int smack_task_getpgid(struct task_struct *p) { - return smk_curacc(task_security(p), MAY_READ); + return smk_curacc_on_task(p, MAY_READ); } /** @@ -1083,7 +1198,7 @@ static int smack_task_getpgid(struct task_struct *p) */ static int smack_task_getsid(struct task_struct *p) { - return smk_curacc(task_security(p), MAY_READ); + return smk_curacc_on_task(p, MAY_READ); } /** @@ -1111,7 +1226,7 @@ static int smack_task_setnice(struct task_struct *p, int nice) rc = cap_task_setnice(p, nice); if (rc == 0) - rc = smk_curacc(task_security(p), MAY_WRITE); + rc = smk_curacc_on_task(p, MAY_WRITE); return rc; } @@ -1128,7 +1243,7 @@ static int smack_task_setioprio(struct task_struct *p, int ioprio) rc = cap_task_setioprio(p, ioprio); if (rc == 0) - rc = smk_curacc(task_security(p), MAY_WRITE); + rc = smk_curacc_on_task(p, MAY_WRITE); return rc; } @@ -1140,7 +1255,7 @@ static int smack_task_setioprio(struct task_struct *p, int ioprio) */ static int smack_task_getioprio(struct task_struct *p) { - return smk_curacc(task_security(p), MAY_READ); + return smk_curacc_on_task(p, MAY_READ); } /** @@ -1158,7 +1273,7 @@ static int smack_task_setscheduler(struct task_struct *p, int policy, rc = cap_task_setscheduler(p, policy, lp); if (rc == 0) - rc = smk_curacc(task_security(p), MAY_WRITE); + rc = smk_curacc_on_task(p, MAY_WRITE); return rc; } @@ -1170,7 +1285,7 @@ static int smack_task_setscheduler(struct task_struct *p, int policy, */ static int smack_task_getscheduler(struct task_struct *p) { - return smk_curacc(task_security(p), MAY_READ); + return smk_curacc_on_task(p, MAY_READ); } /** @@ -1181,7 +1296,7 @@ static int smack_task_getscheduler(struct task_struct *p) */ static int smack_task_movememory(struct task_struct *p) { - return smk_curacc(task_security(p), MAY_WRITE); + return smk_curacc_on_task(p, MAY_WRITE); } /** @@ -1199,18 +1314,23 @@ static int smack_task_movememory(struct task_struct *p) static int smack_task_kill(struct task_struct *p, struct siginfo *info, int sig, u32 secid) { + struct smk_audit_info ad; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK); + smk_ad_setfield_u_tsk(&ad, p); /* * Sending a signal requires that the sender * can write the receiver. */ if (secid == 0) - return smk_curacc(task_security(p), MAY_WRITE); + return smk_curacc(task_security(p), MAY_WRITE, &ad); /* * If the secid isn't 0 we're dealing with some USB IO * specific behavior. This is not clean. For one thing * we can't take privilege into account. */ - return smk_access(smack_from_secid(secid), task_security(p), MAY_WRITE); + return smk_access(smack_from_secid(secid), task_security(p), + MAY_WRITE, &ad); } /** @@ -1221,11 +1341,15 @@ static int smack_task_kill(struct task_struct *p, struct siginfo *info, */ static int smack_task_wait(struct task_struct *p) { + struct smk_audit_info ad; + char *sp = current_security(); + char *tsp = task_security(p); int rc; - rc = smk_access(current_security(), task_security(p), MAY_WRITE); + /* we don't log here, we can be overriden */ + rc = smk_access(sp, tsp, MAY_WRITE, NULL); if (rc == 0) - return 0; + goto out_log; /* * Allow the operation to succeed if either task @@ -1239,8 +1363,12 @@ static int smack_task_wait(struct task_struct *p) * the smack value. */ if (capable(CAP_MAC_OVERRIDE) || has_capability(p, CAP_MAC_OVERRIDE)) - return 0; - + rc = 0; + /* we log only if we didn't get overriden */ + out_log: + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK); + smk_ad_setfield_u_tsk(&ad, p); + smack_log(sp, tsp, MAY_WRITE, rc, &ad); return rc; } @@ -1456,12 +1584,19 @@ static int smack_netlabel_send(struct sock *sk, struct sockaddr_in *sap) int sk_lbl; char *hostsp; struct socket_smack *ssp = sk->sk_security; + struct smk_audit_info ad; rcu_read_lock(); hostsp = smack_host_label(sap); if (hostsp != NULL) { sk_lbl = SMACK_UNLABELED_SOCKET; - rc = smk_access(ssp->smk_out, hostsp, MAY_WRITE); +#ifdef CONFIG_AUDIT + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NET); + ad.a.u.net.family = sap->sin_family; + ad.a.u.net.dport = sap->sin_port; + ad.a.u.net.v4info.daddr = sap->sin_addr.s_addr; +#endif + rc = smk_access(ssp->smk_out, hostsp, MAY_WRITE, &ad); } else { sk_lbl = SMACK_CIPSO_SOCKET; rc = 0; @@ -1657,6 +1792,25 @@ static void smack_shm_free_security(struct shmid_kernel *shp) } /** + * smk_curacc_shm : check if current has access on shm + * @shp : the object + * @access : access requested + * + * Returns 0 if current has the requested access, error code otherwise + */ +static int smk_curacc_shm(struct shmid_kernel *shp, int access) +{ + char *ssp = smack_of_shm(shp); + struct smk_audit_info ad; + +#ifdef CONFIG_AUDIT + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC); + ad.a.u.ipc_id = shp->shm_perm.id; +#endif + return smk_curacc(ssp, access, &ad); +} + +/** * smack_shm_associate - Smack access check for shm * @shp: the object * @shmflg: access requested @@ -1665,11 +1819,10 @@ static void smack_shm_free_security(struct shmid_kernel *shp) */ static int smack_shm_associate(struct shmid_kernel *shp, int shmflg) { - char *ssp = smack_of_shm(shp); int may; may = smack_flags_to_may(shmflg); - return smk_curacc(ssp, may); + return smk_curacc_shm(shp, may); } /** @@ -1681,7 +1834,6 @@ static int smack_shm_associate(struct shmid_kernel *shp, int shmflg) */ static int smack_shm_shmctl(struct shmid_kernel *shp, int cmd) { - char *ssp; int may; switch (cmd) { @@ -1704,9 +1856,7 @@ static int smack_shm_shmctl(struct shmid_kernel *shp, int cmd) default: return -EINVAL; } - - ssp = smack_of_shm(shp); - return smk_curacc(ssp, may); + return smk_curacc_shm(shp, may); } /** @@ -1720,11 +1870,10 @@ static int smack_shm_shmctl(struct shmid_kernel *shp, int cmd) static int smack_shm_shmat(struct shmid_kernel *shp, char __user *shmaddr, int shmflg) { - char *ssp = smack_of_shm(shp); int may; may = smack_flags_to_may(shmflg); - return smk_curacc(ssp, may); + return smk_curacc_shm(shp, may); } /** @@ -1766,6 +1915,25 @@ static void smack_sem_free_security(struct sem_array *sma) } /** + * smk_curacc_sem : check if current has access on sem + * @sma : the object + * @access : access requested + * + * Returns 0 if current has the requested access, error code otherwise + */ +static int smk_curacc_sem(struct sem_array *sma, int access) +{ + char *ssp = smack_of_sem(sma); + struct smk_audit_info ad; + +#ifdef CONFIG_AUDIT + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC); + ad.a.u.ipc_id = sma->sem_perm.id; +#endif + return smk_curacc(ssp, access, &ad); +} + +/** * smack_sem_associate - Smack access check for sem * @sma: the object * @semflg: access requested @@ -1774,11 +1942,10 @@ static void smack_sem_free_security(struct sem_array *sma) */ static int smack_sem_associate(struct sem_array *sma, int semflg) { - char *ssp = smack_of_sem(sma); int may; may = smack_flags_to_may(semflg); - return smk_curacc(ssp, may); + return smk_curacc_sem(sma, may); } /** @@ -1790,7 +1957,6 @@ static int smack_sem_associate(struct sem_array *sma, int semflg) */ static int smack_sem_semctl(struct sem_array *sma, int cmd) { - char *ssp; int may; switch (cmd) { @@ -1819,8 +1985,7 @@ static int smack_sem_semctl(struct sem_array *sma, int cmd) return -EINVAL; } - ssp = smack_of_sem(sma); - return smk_curacc(ssp, may); + return smk_curacc_sem(sma, may); } /** @@ -1837,9 +2002,7 @@ static int smack_sem_semctl(struct sem_array *sma, int cmd) static int smack_sem_semop(struct sem_array *sma, struct sembuf *sops, unsigned nsops, int alter) { - char *ssp = smack_of_sem(sma); - - return smk_curacc(ssp, MAY_READWRITE); + return smk_curacc_sem(sma, MAY_READWRITE); } /** @@ -1881,6 +2044,25 @@ static char *smack_of_msq(struct msg_queue *msq) } /** + * smk_curacc_msq : helper to check if current has access on msq + * @msq : the msq + * @access : access requested + * + * return 0 if current has access, error otherwise + */ +static int smk_curacc_msq(struct msg_queue *msq, int access) +{ + char *msp = smack_of_msq(msq); + struct smk_audit_info ad; + +#ifdef CONFIG_AUDIT + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC); + ad.a.u.ipc_id = msq->q_perm.id; +#endif + return smk_curacc(msp, access, &ad); +} + +/** * smack_msg_queue_associate - Smack access check for msg_queue * @msq: the object * @msqflg: access requested @@ -1889,11 +2071,10 @@ static char *smack_of_msq(struct msg_queue *msq) */ static int smack_msg_queue_associate(struct msg_queue *msq, int msqflg) { - char *msp = smack_of_msq(msq); int may; may = smack_flags_to_may(msqflg); - return smk_curacc(msp, may); + return smk_curacc_msq(msq, may); } /** @@ -1905,7 +2086,6 @@ static int smack_msg_queue_associate(struct msg_queue *msq, int msqflg) */ static int smack_msg_queue_msgctl(struct msg_queue *msq, int cmd) { - char *msp; int may; switch (cmd) { @@ -1927,8 +2107,7 @@ static int smack_msg_queue_msgctl(struct msg_queue *msq, int cmd) return -EINVAL; } - msp = smack_of_msq(msq); - return smk_curacc(msp, may); + return smk_curacc_msq(msq, may); } /** @@ -1942,11 +2121,10 @@ static int smack_msg_queue_msgctl(struct msg_queue *msq, int cmd) static int smack_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg) { - char *msp = smack_of_msq(msq); - int rc; + int may; - rc = smack_flags_to_may(msqflg); - return smk_curacc(msp, rc); + may = smack_flags_to_may(msqflg); + return smk_curacc_msq(msq, may); } /** @@ -1962,9 +2140,7 @@ static int smack_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, static int smack_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg, struct task_struct *target, long type, int mode) { - char *msp = smack_of_msq(msq); - - return smk_curacc(msp, MAY_READWRITE); + return smk_curacc_msq(msq, MAY_READWRITE); } /** @@ -1977,10 +2153,14 @@ static int smack_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg, static int smack_ipc_permission(struct kern_ipc_perm *ipp, short flag) { char *isp = ipp->security; - int may; + int may = smack_flags_to_may(flag); + struct smk_audit_info ad; - may = smack_flags_to_may(flag); - return smk_curacc(isp, may); +#ifdef CONFIG_AUDIT + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC); + ad.a.u.ipc_id = ipp->id; +#endif + return smk_curacc(isp, may, &ad); } /** @@ -2239,8 +2419,12 @@ static int smack_unix_stream_connect(struct socket *sock, { struct inode *sp = SOCK_INODE(sock); struct inode *op = SOCK_INODE(other); + struct smk_audit_info ad; - return smk_access(smk_of_inode(sp), smk_of_inode(op), MAY_READWRITE); + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NET); + smk_ad_setfield_u_net_sk(&ad, other->sk); + return smk_access(smk_of_inode(sp), smk_of_inode(op), + MAY_READWRITE, &ad); } /** @@ -2255,8 +2439,11 @@ static int smack_unix_may_send(struct socket *sock, struct socket *other) { struct inode *sp = SOCK_INODE(sock); struct inode *op = SOCK_INODE(other); + struct smk_audit_info ad; - return smk_access(smk_of_inode(sp), smk_of_inode(op), MAY_WRITE); + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NET); + smk_ad_setfield_u_net_sk(&ad, other->sk); + return smk_access(smk_of_inode(sp), smk_of_inode(op), MAY_WRITE, &ad); } /** @@ -2371,7 +2558,7 @@ static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) char smack[SMK_LABELLEN]; char *csp; int rc; - + struct smk_audit_info ad; if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6) return 0; @@ -2389,13 +2576,19 @@ static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) netlbl_secattr_destroy(&secattr); +#ifdef CONFIG_AUDIT + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NET); + ad.a.u.net.family = sk->sk_family; + ad.a.u.net.netif = skb->iif; + ipv4_skb_to_auditdata(skb, &ad.a, NULL); +#endif /* * Receiving a packet requires that the other end * be able to write here. Read access is not required. * This is the simplist possible security model * for networking. */ - rc = smk_access(csp, ssp->smk_in, MAY_WRITE); + rc = smk_access(csp, ssp->smk_in, MAY_WRITE, &ad); if (rc != 0) netlbl_skbuff_err(skb, rc, 0); return rc; @@ -2524,6 +2717,7 @@ static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb, struct iphdr *hdr; char smack[SMK_LABELLEN]; int rc; + struct smk_audit_info ad; /* handle mapped IPv4 packets arriving via IPv6 sockets */ if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) @@ -2537,11 +2731,17 @@ static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb, strncpy(smack, smack_known_huh.smk_known, SMK_MAXLEN); netlbl_secattr_destroy(&secattr); +#ifdef CONFIG_AUDIT + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NET); + ad.a.u.net.family = family; + ad.a.u.net.netif = skb->iif; + ipv4_skb_to_auditdata(skb, &ad.a, NULL); +#endif /* * Receiving a packet requires that the other end be able to write * here. Read access is not required. */ - rc = smk_access(smack, ssp->smk_in, MAY_WRITE); + rc = smk_access(smack, ssp->smk_in, MAY_WRITE, &ad); if (rc != 0) return rc; @@ -2643,6 +2843,7 @@ static int smack_key_permission(key_ref_t key_ref, const struct cred *cred, key_perm_t perm) { struct key *keyp; + struct smk_audit_info ad; keyp = key_ref_to_ptr(key_ref); if (keyp == NULL) @@ -2658,8 +2859,13 @@ static int smack_key_permission(key_ref_t key_ref, */ if (cred->security == NULL) return -EACCES; - - return smk_access(cred->security, keyp->security, MAY_READWRITE); +#ifdef CONFIG_AUDIT + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_KEY); + ad.a.u.key_struct.key = keyp->serial; + ad.a.u.key_struct.key_desc = keyp->description; +#endif + return smk_access(cred->security, keyp->security, + MAY_READWRITE, &ad); } #endif /* CONFIG_KEYS */ @@ -2828,15 +3034,7 @@ struct security_operations smack_ops = { .ptrace_may_access = smack_ptrace_may_access, .ptrace_traceme = smack_ptrace_traceme, - .capget = cap_capget, - .capset = cap_capset, - .capable = cap_capable, .syslog = smack_syslog, - .settime = cap_settime, - .vm_enough_memory = cap_vm_enough_memory, - - .bprm_set_creds = cap_bprm_set_creds, - .bprm_secureexec = cap_bprm_secureexec, .sb_alloc_security = smack_sb_alloc_security, .sb_free_security = smack_sb_free_security, @@ -2860,8 +3058,6 @@ struct security_operations smack_ops = { .inode_post_setxattr = smack_inode_post_setxattr, .inode_getxattr = smack_inode_getxattr, .inode_removexattr = smack_inode_removexattr, - .inode_need_killpriv = cap_inode_need_killpriv, - .inode_killpriv = cap_inode_killpriv, .inode_getsecurity = smack_inode_getsecurity, .inode_setsecurity = smack_inode_setsecurity, .inode_listsecurity = smack_inode_listsecurity, @@ -2882,7 +3078,6 @@ struct security_operations smack_ops = { .cred_commit = smack_cred_commit, .kernel_act_as = smack_kernel_act_as, .kernel_create_files_as = smack_kernel_create_files_as, - .task_fix_setuid = cap_task_fix_setuid, .task_setpgid = smack_task_setpgid, .task_getpgid = smack_task_getpgid, .task_getsid = smack_task_getsid, @@ -2896,7 +3091,6 @@ struct security_operations smack_ops = { .task_kill = smack_task_kill, .task_wait = smack_task_wait, .task_to_inode = smack_task_to_inode, - .task_prctl = cap_task_prctl, .ipc_permission = smack_ipc_permission, .ipc_getsecid = smack_ipc_getsecid, @@ -2923,9 +3117,6 @@ struct security_operations smack_ops = { .sem_semctl = smack_sem_semctl, .sem_semop = smack_sem_semop, - .netlink_send = cap_netlink_send, - .netlink_recv = cap_netlink_recv, - .d_instantiate = smack_d_instantiate, .getprocattr = smack_getprocattr, diff --git a/security/smack/smackfs.c b/security/smack/smackfs.c index 11d2cb1..f83a809 100644 --- a/security/smack/smackfs.c +++ b/security/smack/smackfs.c @@ -41,6 +41,7 @@ enum smk_inos { SMK_AMBIENT = 7, /* internet ambient label */ SMK_NETLBLADDR = 8, /* single label hosts */ SMK_ONLYCAP = 9, /* the only "capable" label */ + SMK_LOGGING = 10, /* logging */ }; /* @@ -775,7 +776,7 @@ static ssize_t smk_write_netlbladdr(struct file *file, const char __user *buf, struct sockaddr_in newname; char smack[SMK_LABELLEN]; char *sp; - char data[SMK_NETLBLADDRMAX]; + char data[SMK_NETLBLADDRMAX + 1]; char *host = (char *)&newname.sin_addr.s_addr; int rc; struct netlbl_audit audit_info; @@ -1192,6 +1193,69 @@ static const struct file_operations smk_onlycap_ops = { }; /** + * smk_read_logging - read() for /smack/logging + * @filp: file pointer, not actually used + * @buf: where to put the result + * @cn: maximum to send along + * @ppos: where to start + * + * Returns number of bytes read or error code, as appropriate + */ +static ssize_t smk_read_logging(struct file *filp, char __user *buf, + size_t count, loff_t *ppos) +{ + char temp[32]; + ssize_t rc; + + if (*ppos != 0) + return 0; + + sprintf(temp, "%d\n", log_policy); + rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp)); + return rc; +} + +/** + * smk_write_logging - write() for /smack/logging + * @file: file pointer, not actually used + * @buf: where to get the data from + * @count: bytes sent + * @ppos: where to start + * + * Returns number of bytes written or error code, as appropriate + */ +static ssize_t smk_write_logging(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + char temp[32]; + int i; + + if (!capable(CAP_MAC_ADMIN)) + return -EPERM; + + if (count >= sizeof(temp) || count == 0) + return -EINVAL; + + if (copy_from_user(temp, buf, count) != 0) + return -EFAULT; + + temp[count] = '\0'; + + if (sscanf(temp, "%d", &i) != 1) + return -EINVAL; + if (i < 0 || i > 3) + return -EINVAL; + log_policy = i; + return count; +} + + + +static const struct file_operations smk_logging_ops = { + .read = smk_read_logging, + .write = smk_write_logging, +}; +/** * smk_fill_super - fill the /smackfs superblock * @sb: the empty superblock * @data: unused @@ -1221,6 +1285,8 @@ static int smk_fill_super(struct super_block *sb, void *data, int silent) {"netlabel", &smk_netlbladdr_ops, S_IRUGO|S_IWUSR}, [SMK_ONLYCAP] = {"onlycap", &smk_onlycap_ops, S_IRUGO|S_IWUSR}, + [SMK_LOGGING] = + {"logging", &smk_logging_ops, S_IRUGO|S_IWUSR}, /* last one */ {""} }; diff --git a/security/tomoyo/common.c b/security/tomoyo/common.c index ddfb9cc..fdd1f4b 100644 --- a/security/tomoyo/common.c +++ b/security/tomoyo/common.c @@ -28,7 +28,13 @@ static const char *tomoyo_mode_2[4] = { "disabled", "enabled", "enabled", "enabled" }; -/* Table for profile. */ +/* + * tomoyo_control_array is a static data which contains + * + * (1) functionality name used by /sys/kernel/security/tomoyo/profile . + * (2) initial values for "struct tomoyo_profile". + * (3) max values for "struct tomoyo_profile". + */ static struct { const char *keyword; unsigned int current_value; @@ -39,7 +45,13 @@ static struct { [TOMOYO_VERBOSE] = { "TOMOYO_VERBOSE", 1, 1 }, }; -/* Profile table. Memory is allocated as needed. */ +/* + * tomoyo_profile is a structure which is used for holding the mode of access + * controls. TOMOYO has 4 modes: disabled, learning, permissive, enforcing. + * An administrator can define up to 256 profiles. + * The ->profile of "struct tomoyo_domain_info" is used for remembering + * the profile's number (0 - 255) assigned to that domain. + */ static struct tomoyo_profile { unsigned int value[TOMOYO_MAX_CONTROL_INDEX]; const struct tomoyo_path_info *comment; @@ -428,7 +440,6 @@ void tomoyo_fill_path_info(struct tomoyo_path_info *ptr) const char *name = ptr->name; const int len = strlen(name); - ptr->total_len = len; ptr->const_len = tomoyo_const_part_length(name); ptr->is_dir = len && (name[len - 1] == '/'); ptr->is_patterned = (ptr->const_len < len); @@ -866,7 +877,6 @@ static struct tomoyo_profile *tomoyo_find_or_assign_new_profile(const unsigned if (profile >= TOMOYO_MAX_PROFILES) return NULL; - /***** EXCLUSIVE SECTION START *****/ mutex_lock(&lock); ptr = tomoyo_profile_ptr[profile]; if (ptr) @@ -880,7 +890,6 @@ static struct tomoyo_profile *tomoyo_find_or_assign_new_profile(const unsigned tomoyo_profile_ptr[profile] = ptr; ok: mutex_unlock(&lock); - /***** EXCLUSIVE SECTION END *****/ return ptr; } @@ -1009,7 +1018,19 @@ static int tomoyo_read_profile(struct tomoyo_io_buffer *head) return 0; } -/* Structure for policy manager. */ +/* + * tomoyo_policy_manager_entry is a structure which is used for holding list of + * domainnames or programs which are permitted to modify configuration via + * /sys/kernel/security/tomoyo/ interface. + * It has following fields. + * + * (1) "list" which is linked to tomoyo_policy_manager_list . + * (2) "manager" is a domainname or a program's pathname. + * (3) "is_domain" is a bool which is true if "manager" is a domainname, false + * otherwise. + * (4) "is_deleted" is a bool which is true if marked as deleted, false + * otherwise. + */ struct tomoyo_policy_manager_entry { struct list_head list; /* A path to program or a domainname. */ @@ -1018,7 +1039,36 @@ struct tomoyo_policy_manager_entry { bool is_deleted; /* True if this entry is deleted. */ }; -/* The list for "struct tomoyo_policy_manager_entry". */ +/* + * tomoyo_policy_manager_list is used for holding list of domainnames or + * programs which are permitted to modify configuration via + * /sys/kernel/security/tomoyo/ interface. + * + * An entry is added by + * + * # echo '<kernel> /sbin/mingetty /bin/login /bin/bash' > \ + * /sys/kernel/security/tomoyo/manager + * (if you want to specify by a domainname) + * + * or + * + * # echo '/usr/lib/ccs/editpolicy' > /sys/kernel/security/tomoyo/manager + * (if you want to specify by a program's location) + * + * and is deleted by + * + * # echo 'delete <kernel> /sbin/mingetty /bin/login /bin/bash' > \ + * /sys/kernel/security/tomoyo/manager + * + * or + * + * # echo 'delete /usr/lib/ccs/editpolicy' > \ + * /sys/kernel/security/tomoyo/manager + * + * and all entries are retrieved by + * + * # cat /sys/kernel/security/tomoyo/manager + */ static LIST_HEAD(tomoyo_policy_manager_list); static DECLARE_RWSEM(tomoyo_policy_manager_list_lock); @@ -1050,7 +1100,6 @@ static int tomoyo_update_manager_entry(const char *manager, saved_manager = tomoyo_save_name(manager); if (!saved_manager) return -ENOMEM; - /***** EXCLUSIVE SECTION START *****/ down_write(&tomoyo_policy_manager_list_lock); list_for_each_entry(ptr, &tomoyo_policy_manager_list, list) { if (ptr->manager != saved_manager) @@ -1072,7 +1121,6 @@ static int tomoyo_update_manager_entry(const char *manager, error = 0; out: up_write(&tomoyo_policy_manager_list_lock); - /***** EXCLUSIVE SECTION END *****/ return error; } @@ -1117,10 +1165,9 @@ static int tomoyo_read_manager_policy(struct tomoyo_io_buffer *head) list); if (ptr->is_deleted) continue; - if (!tomoyo_io_printf(head, "%s\n", ptr->manager->name)) { - done = false; + done = tomoyo_io_printf(head, "%s\n", ptr->manager->name); + if (!done) break; - } } up_read(&tomoyo_policy_manager_list_lock); head->read_eof = done; @@ -1197,13 +1244,11 @@ static bool tomoyo_is_select_one(struct tomoyo_io_buffer *head, if (sscanf(data, "pid=%u", &pid) == 1) { struct task_struct *p; - /***** CRITICAL SECTION START *****/ read_lock(&tasklist_lock); p = find_task_by_vpid(pid); if (p) domain = tomoyo_real_domain(p); read_unlock(&tasklist_lock); - /***** CRITICAL SECTION END *****/ } else if (!strncmp(data, "domain=", 7)) { if (tomoyo_is_domain_def(data + 7)) { down_read(&tomoyo_domain_list_lock); @@ -1447,15 +1492,14 @@ static int tomoyo_read_domain_policy(struct tomoyo_io_buffer *head) TOMOYO_DOMAIN_FLAGS_IGNORE_GLOBAL_ALLOW_READ) ignore_global_allow_read = TOMOYO_KEYWORD_IGNORE_GLOBAL_ALLOW_READ "\n"; - if (!tomoyo_io_printf(head, - "%s\n" TOMOYO_KEYWORD_USE_PROFILE "%u\n" - "%s%s%s\n", domain->domainname->name, - domain->profile, quota_exceeded, - transition_failed, - ignore_global_allow_read)) { - done = false; + done = tomoyo_io_printf(head, "%s\n" TOMOYO_KEYWORD_USE_PROFILE + "%u\n%s%s%s\n", + domain->domainname->name, + domain->profile, quota_exceeded, + transition_failed, + ignore_global_allow_read); + if (!done) break; - } head->read_step = 2; acl_loop: if (head->read_step == 3) @@ -1463,24 +1507,22 @@ acl_loop: /* Print ACL entries in the domain. */ down_read(&tomoyo_domain_acl_info_list_lock); list_for_each_cookie(apos, head->read_var2, - &domain->acl_info_list) { + &domain->acl_info_list) { struct tomoyo_acl_info *ptr = list_entry(apos, struct tomoyo_acl_info, - list); - if (!tomoyo_print_entry(head, ptr)) { - done = false; + list); + done = tomoyo_print_entry(head, ptr); + if (!done) break; - } } up_read(&tomoyo_domain_acl_info_list_lock); if (!done) break; head->read_step = 3; tail_mark: - if (!tomoyo_io_printf(head, "\n")) { - done = false; + done = tomoyo_io_printf(head, "\n"); + if (!done) break; - } head->read_step = 1; if (head->read_single_domain) break; @@ -1550,11 +1592,10 @@ static int tomoyo_read_domain_profile(struct tomoyo_io_buffer *head) domain = list_entry(pos, struct tomoyo_domain_info, list); if (domain->is_deleted) continue; - if (!tomoyo_io_printf(head, "%u %s\n", domain->profile, - domain->domainname->name)) { - done = false; + done = tomoyo_io_printf(head, "%u %s\n", domain->profile, + domain->domainname->name); + if (!done) break; - } } up_read(&tomoyo_domain_list_lock); head->read_eof = done; @@ -1594,13 +1635,11 @@ static int tomoyo_read_pid(struct tomoyo_io_buffer *head) const int pid = head->read_step; struct task_struct *p; struct tomoyo_domain_info *domain = NULL; - /***** CRITICAL SECTION START *****/ read_lock(&tasklist_lock); p = find_task_by_vpid(pid); if (p) domain = tomoyo_real_domain(p); read_unlock(&tasklist_lock); - /***** CRITICAL SECTION END *****/ if (domain) tomoyo_io_printf(head, "%d %u %s", pid, domain->profile, domain->domainname->name); @@ -2138,7 +2177,13 @@ static ssize_t tomoyo_write(struct file *file, const char __user *buf, return tomoyo_write_control(file, buf, count); } -/* Operations for /sys/kernel/security/tomoyo/ interface. */ +/* + * tomoyo_operations is a "struct file_operations" which is used for handling + * /sys/kernel/security/tomoyo/ interface. + * + * Some files under /sys/kernel/security/tomoyo/ directory accept open(O_RDWR). + * See tomoyo_io_buffer for internals. + */ static const struct file_operations tomoyo_operations = { .open = tomoyo_open, .release = tomoyo_release, diff --git a/security/tomoyo/common.h b/security/tomoyo/common.h index 678f4ff..6d6ba09 100644 --- a/security/tomoyo/common.h +++ b/security/tomoyo/common.h @@ -26,16 +26,43 @@ struct dentry; struct vfsmount; -/* Temporary buffer for holding pathnames. */ +/* + * tomoyo_page_buffer is a structure which is used for holding a pathname + * obtained from "struct dentry" and "struct vfsmount" pair. + * As of now, it is 4096 bytes. If users complain that 4096 bytes is too small + * (because TOMOYO escapes non ASCII printable characters using \ooo format), + * we will make the buffer larger. + */ struct tomoyo_page_buffer { char buffer[4096]; }; -/* Structure for holding a token. */ +/* + * tomoyo_path_info is a structure which is used for holding a string data + * used by TOMOYO. + * This structure has several fields for supporting pattern matching. + * + * (1) "name" is the '\0' terminated string data. + * (2) "hash" is full_name_hash(name, strlen(name)). + * This allows tomoyo_pathcmp() to compare by hash before actually compare + * using strcmp(). + * (3) "const_len" is the length of the initial segment of "name" which + * consists entirely of non wildcard characters. In other words, the length + * which we can compare two strings using strncmp(). + * (4) "is_dir" is a bool which is true if "name" ends with "/", + * false otherwise. + * TOMOYO distinguishes directory and non-directory. A directory ends with + * "/" and non-directory does not end with "/". + * (5) "is_patterned" is a bool which is true if "name" contains wildcard + * characters, false otherwise. This allows TOMOYO to use "hash" and + * strcmp() for string comparison if "is_patterned" is false. + * (6) "depth" is calculated using the number of "/" characters in "name". + * This allows TOMOYO to avoid comparing two pathnames which never match + * (e.g. whether "/var/www/html/index.html" matches "/tmp/sh-thd-\$"). + */ struct tomoyo_path_info { const char *name; u32 hash; /* = full_name_hash(name, strlen(name)) */ - u16 total_len; /* = strlen(name) */ u16 const_len; /* = tomoyo_const_part_length(name) */ bool is_dir; /* = tomoyo_strendswith(name, "/") */ bool is_patterned; /* = tomoyo_path_contains_pattern(name) */ @@ -51,7 +78,20 @@ struct tomoyo_path_info { */ #define TOMOYO_MAX_PATHNAME_LEN 4000 -/* Structure for holding requested pathname. */ +/* + * tomoyo_path_info_with_data is a structure which is used for holding a + * pathname obtained from "struct dentry" and "struct vfsmount" pair. + * + * "struct tomoyo_path_info_with_data" consists of "struct tomoyo_path_info" + * and buffer for the pathname, while "struct tomoyo_page_buffer" consists of + * buffer for the pathname only. + * + * "struct tomoyo_path_info_with_data" is intended to allow TOMOYO to release + * both "struct tomoyo_path_info" and buffer for the pathname by single kfree() + * so that we don't need to return two pointers to the caller. If the caller + * puts "struct tomoyo_path_info" on stack memory, we will be able to remove + * "struct tomoyo_path_info_with_data". + */ struct tomoyo_path_info_with_data { /* Keep "head" first, for this pointer is passed to tomoyo_free(). */ struct tomoyo_path_info head; @@ -61,7 +101,15 @@ struct tomoyo_path_info_with_data { }; /* - * Common header for holding ACL entries. + * tomoyo_acl_info is a structure which is used for holding + * + * (1) "list" which is linked to the ->acl_info_list of + * "struct tomoyo_domain_info" + * (2) "type" which tells + * (a) type & 0x7F : type of the entry (either + * "struct tomoyo_single_path_acl_record" or + * "struct tomoyo_double_path_acl_record") + * (b) type & 0x80 : whether the entry is marked as "deleted". * * Packing "struct tomoyo_acl_info" allows * "struct tomoyo_single_path_acl_record" to embed "u16" and @@ -81,7 +129,28 @@ struct tomoyo_acl_info { /* This ACL entry is deleted. */ #define TOMOYO_ACL_DELETED 0x80 -/* Structure for domain information. */ +/* + * tomoyo_domain_info is a structure which is used for holding permissions + * (e.g. "allow_read /lib/libc-2.5.so") given to each domain. + * It has following fields. + * + * (1) "list" which is linked to tomoyo_domain_list . + * (2) "acl_info_list" which is linked to "struct tomoyo_acl_info". + * (3) "domainname" which holds the name of the domain. + * (4) "profile" which remembers profile number assigned to this domain. + * (5) "is_deleted" is a bool which is true if this domain is marked as + * "deleted", false otherwise. + * (6) "quota_warned" is a bool which is used for suppressing warning message + * when learning mode learned too much entries. + * (7) "flags" which remembers this domain's attributes. + * + * A domain's lifecycle is an analogy of files on / directory. + * Multiple domains with the same domainname cannot be created (as with + * creating files with the same filename fails with -EEXIST). + * If a process reached a domain, that process can reside in that domain after + * that domain is marked as "deleted" (as with a process can access an already + * open()ed file after that file was unlink()ed). + */ struct tomoyo_domain_info { struct list_head list; struct list_head acl_info_list; @@ -108,10 +177,18 @@ struct tomoyo_domain_info { #define TOMOYO_DOMAIN_FLAGS_TRANSITION_FAILED 2 /* - * Structure for "allow_read/write", "allow_execute", "allow_read", - * "allow_write", "allow_create", "allow_unlink", "allow_mkdir", "allow_rmdir", - * "allow_mkfifo", "allow_mksock", "allow_mkblock", "allow_mkchar", - * "allow_truncate", "allow_symlink" and "allow_rewrite" directive. + * tomoyo_single_path_acl_record is a structure which is used for holding an + * entry with one pathname operation (e.g. open(), mkdir()). + * It has following fields. + * + * (1) "head" which is a "struct tomoyo_acl_info". + * (2) "perm" which is a bitmask of permitted operations. + * (3) "filename" is the pathname. + * + * Directives held by this structure are "allow_read/write", "allow_execute", + * "allow_read", "allow_write", "allow_create", "allow_unlink", "allow_mkdir", + * "allow_rmdir", "allow_mkfifo", "allow_mksock", "allow_mkblock", + * "allow_mkchar", "allow_truncate", "allow_symlink" and "allow_rewrite". */ struct tomoyo_single_path_acl_record { struct tomoyo_acl_info head; /* type = TOMOYO_TYPE_SINGLE_PATH_ACL */ @@ -120,7 +197,18 @@ struct tomoyo_single_path_acl_record { const struct tomoyo_path_info *filename; }; -/* Structure for "allow_rename" and "allow_link" directive. */ +/* + * tomoyo_double_path_acl_record is a structure which is used for holding an + * entry with two pathnames operation (i.e. link() and rename()). + * It has following fields. + * + * (1) "head" which is a "struct tomoyo_acl_info". + * (2) "perm" which is a bitmask of permitted operations. + * (3) "filename1" is the source/old pathname. + * (4) "filename2" is the destination/new pathname. + * + * Directives held by this structure are "allow_rename" and "allow_link". + */ struct tomoyo_double_path_acl_record { struct tomoyo_acl_info head; /* type = TOMOYO_TYPE_DOUBLE_PATH_ACL */ u8 perm; @@ -153,7 +241,29 @@ struct tomoyo_double_path_acl_record { #define TOMOYO_VERBOSE 2 #define TOMOYO_MAX_CONTROL_INDEX 3 -/* Structure for reading/writing policy via securityfs interfaces. */ +/* + * tomoyo_io_buffer is a structure which is used for reading and modifying + * configuration via /sys/kernel/security/tomoyo/ interface. + * It has many fields. ->read_var1 , ->read_var2 , ->write_var1 are used as + * cursors. + * + * Since the content of /sys/kernel/security/tomoyo/domain_policy is a list of + * "struct tomoyo_domain_info" entries and each "struct tomoyo_domain_info" + * entry has a list of "struct tomoyo_acl_info", we need two cursors when + * reading (one is for traversing tomoyo_domain_list and the other is for + * traversing "struct tomoyo_acl_info"->acl_info_list ). + * + * If a line written to /sys/kernel/security/tomoyo/domain_policy starts with + * "select ", TOMOYO seeks the cursor ->read_var1 and ->write_var1 to the + * domain with the domainname specified by the rest of that line (NULL is set + * if seek failed). + * If a line written to /sys/kernel/security/tomoyo/domain_policy starts with + * "delete ", TOMOYO deletes an entry or a domain specified by the rest of that + * line (->write_var1 is set to NULL if a domain was deleted). + * If a line written to /sys/kernel/security/tomoyo/domain_policy starts with + * neither "select " nor "delete ", an entry or a domain specified by that line + * is appended. + */ struct tomoyo_io_buffer { int (*read) (struct tomoyo_io_buffer *); int (*write) (struct tomoyo_io_buffer *); diff --git a/security/tomoyo/domain.c b/security/tomoyo/domain.c index 2d67487..1d8b169 100644 --- a/security/tomoyo/domain.c +++ b/security/tomoyo/domain.c @@ -19,11 +19,63 @@ /* The initial domain. */ struct tomoyo_domain_info tomoyo_kernel_domain; -/* The list for "struct tomoyo_domain_info". */ +/* + * tomoyo_domain_list is used for holding list of domains. + * The ->acl_info_list of "struct tomoyo_domain_info" is used for holding + * permissions (e.g. "allow_read /lib/libc-2.5.so") given to each domain. + * + * An entry is added by + * + * # ( echo "<kernel>"; echo "allow_execute /sbin/init" ) > \ + * /sys/kernel/security/tomoyo/domain_policy + * + * and is deleted by + * + * # ( echo "<kernel>"; echo "delete allow_execute /sbin/init" ) > \ + * /sys/kernel/security/tomoyo/domain_policy + * + * and all entries are retrieved by + * + * # cat /sys/kernel/security/tomoyo/domain_policy + * + * A domain is added by + * + * # echo "<kernel>" > /sys/kernel/security/tomoyo/domain_policy + * + * and is deleted by + * + * # echo "delete <kernel>" > /sys/kernel/security/tomoyo/domain_policy + * + * and all domains are retrieved by + * + * # grep '^<kernel>' /sys/kernel/security/tomoyo/domain_policy + * + * Normally, a domainname is monotonically getting longer because a domainname + * which the process will belong to if an execve() operation succeeds is + * defined as a concatenation of "current domainname" + "pathname passed to + * execve()". + * See tomoyo_domain_initializer_list and tomoyo_domain_keeper_list for + * exceptions. + */ LIST_HEAD(tomoyo_domain_list); DECLARE_RWSEM(tomoyo_domain_list_lock); -/* Structure for "initialize_domain" and "no_initialize_domain" keyword. */ +/* + * tomoyo_domain_initializer_entry is a structure which is used for holding + * "initialize_domain" and "no_initialize_domain" entries. + * It has following fields. + * + * (1) "list" which is linked to tomoyo_domain_initializer_list . + * (2) "domainname" which is "a domainname" or "the last component of a + * domainname". This field is NULL if "from" clause is not specified. + * (3) "program" which is a program's pathname. + * (4) "is_deleted" is a bool which is true if marked as deleted, false + * otherwise. + * (5) "is_not" is a bool which is true if "no_initialize_domain", false + * otherwise. + * (6) "is_last_name" is a bool which is true if "domainname" is "the last + * component of a domainname", false otherwise. + */ struct tomoyo_domain_initializer_entry { struct list_head list; const struct tomoyo_path_info *domainname; /* This may be NULL */ @@ -34,7 +86,23 @@ struct tomoyo_domain_initializer_entry { bool is_last_name; }; -/* Structure for "keep_domain" and "no_keep_domain" keyword. */ +/* + * tomoyo_domain_keeper_entry is a structure which is used for holding + * "keep_domain" and "no_keep_domain" entries. + * It has following fields. + * + * (1) "list" which is linked to tomoyo_domain_keeper_list . + * (2) "domainname" which is "a domainname" or "the last component of a + * domainname". + * (3) "program" which is a program's pathname. + * This field is NULL if "from" clause is not specified. + * (4) "is_deleted" is a bool which is true if marked as deleted, false + * otherwise. + * (5) "is_not" is a bool which is true if "no_initialize_domain", false + * otherwise. + * (6) "is_last_name" is a bool which is true if "domainname" is "the last + * component of a domainname", false otherwise. + */ struct tomoyo_domain_keeper_entry { struct list_head list; const struct tomoyo_path_info *domainname; @@ -45,7 +113,16 @@ struct tomoyo_domain_keeper_entry { bool is_last_name; }; -/* Structure for "alias" keyword. */ +/* + * tomoyo_alias_entry is a structure which is used for holding "alias" entries. + * It has following fields. + * + * (1) "list" which is linked to tomoyo_alias_list . + * (2) "original_name" which is a dereferenced pathname. + * (3) "aliased_name" which is a symlink's pathname. + * (4) "is_deleted" is a bool which is true if marked as deleted, false + * otherwise. + */ struct tomoyo_alias_entry { struct list_head list; const struct tomoyo_path_info *original_name; @@ -67,14 +144,12 @@ void tomoyo_set_domain_flag(struct tomoyo_domain_info *domain, { /* We need to serialize because this is bitfield operation. */ static DEFINE_SPINLOCK(lock); - /***** CRITICAL SECTION START *****/ spin_lock(&lock); if (!is_delete) domain->flags |= flags; else domain->flags &= ~flags; spin_unlock(&lock); - /***** CRITICAL SECTION END *****/ } /** @@ -94,7 +169,42 @@ const char *tomoyo_get_last_name(const struct tomoyo_domain_info *domain) return cp0; } -/* The list for "struct tomoyo_domain_initializer_entry". */ +/* + * tomoyo_domain_initializer_list is used for holding list of programs which + * triggers reinitialization of domainname. Normally, a domainname is + * monotonically getting longer. But sometimes, we restart daemon programs. + * It would be convenient for us that "a daemon started upon system boot" and + * "the daemon restarted from console" belong to the same domain. Thus, TOMOYO + * provides a way to shorten domainnames. + * + * An entry is added by + * + * # echo 'initialize_domain /usr/sbin/httpd' > \ + * /sys/kernel/security/tomoyo/exception_policy + * + * and is deleted by + * + * # echo 'delete initialize_domain /usr/sbin/httpd' > \ + * /sys/kernel/security/tomoyo/exception_policy + * + * and all entries are retrieved by + * + * # grep ^initialize_domain /sys/kernel/security/tomoyo/exception_policy + * + * In the example above, /usr/sbin/httpd will belong to + * "<kernel> /usr/sbin/httpd" domain. + * + * You may specify a domainname using "from" keyword. + * "initialize_domain /usr/sbin/httpd from <kernel> /etc/rc.d/init.d/httpd" + * will cause "/usr/sbin/httpd" executed from "<kernel> /etc/rc.d/init.d/httpd" + * domain to belong to "<kernel> /usr/sbin/httpd" domain. + * + * You may add "no_" prefix to "initialize_domain". + * "initialize_domain /usr/sbin/httpd" and + * "no_initialize_domain /usr/sbin/httpd from <kernel> /etc/rc.d/init.d/httpd" + * will cause "/usr/sbin/httpd" to belong to "<kernel> /usr/sbin/httpd" domain + * unless executed from "<kernel> /etc/rc.d/init.d/httpd" domain. + */ static LIST_HEAD(tomoyo_domain_initializer_list); static DECLARE_RWSEM(tomoyo_domain_initializer_list_lock); @@ -135,7 +245,6 @@ static int tomoyo_update_domain_initializer_entry(const char *domainname, saved_program = tomoyo_save_name(program); if (!saved_program) return -ENOMEM; - /***** EXCLUSIVE SECTION START *****/ down_write(&tomoyo_domain_initializer_list_lock); list_for_each_entry(ptr, &tomoyo_domain_initializer_list, list) { if (ptr->is_not != is_not || @@ -161,7 +270,6 @@ static int tomoyo_update_domain_initializer_entry(const char *domainname, error = 0; out: up_write(&tomoyo_domain_initializer_list_lock); - /***** EXCLUSIVE SECTION END *****/ return error; } @@ -193,13 +301,12 @@ bool tomoyo_read_domain_initializer_policy(struct tomoyo_io_buffer *head) from = " from "; domain = ptr->domainname->name; } - if (!tomoyo_io_printf(head, - "%s" TOMOYO_KEYWORD_INITIALIZE_DOMAIN - "%s%s%s\n", no, ptr->program->name, from, - domain)) { - done = false; + done = tomoyo_io_printf(head, + "%s" TOMOYO_KEYWORD_INITIALIZE_DOMAIN + "%s%s%s\n", no, ptr->program->name, + from, domain); + if (!done) break; - } } up_read(&tomoyo_domain_initializer_list_lock); return done; @@ -273,7 +380,44 @@ static bool tomoyo_is_domain_initializer(const struct tomoyo_path_info * return flag; } -/* The list for "struct tomoyo_domain_keeper_entry". */ +/* + * tomoyo_domain_keeper_list is used for holding list of domainnames which + * suppresses domain transition. Normally, a domainname is monotonically + * getting longer. But sometimes, we want to suppress domain transition. + * It would be convenient for us that programs executed from a login session + * belong to the same domain. Thus, TOMOYO provides a way to suppress domain + * transition. + * + * An entry is added by + * + * # echo 'keep_domain <kernel> /usr/sbin/sshd /bin/bash' > \ + * /sys/kernel/security/tomoyo/exception_policy + * + * and is deleted by + * + * # echo 'delete keep_domain <kernel> /usr/sbin/sshd /bin/bash' > \ + * /sys/kernel/security/tomoyo/exception_policy + * + * and all entries are retrieved by + * + * # grep ^keep_domain /sys/kernel/security/tomoyo/exception_policy + * + * In the example above, any process which belongs to + * "<kernel> /usr/sbin/sshd /bin/bash" domain will remain in that domain, + * unless explicitly specified by "initialize_domain" or "no_keep_domain". + * + * You may specify a program using "from" keyword. + * "keep_domain /bin/pwd from <kernel> /usr/sbin/sshd /bin/bash" + * will cause "/bin/pwd" executed from "<kernel> /usr/sbin/sshd /bin/bash" + * domain to remain in "<kernel> /usr/sbin/sshd /bin/bash" domain. + * + * You may add "no_" prefix to "keep_domain". + * "keep_domain <kernel> /usr/sbin/sshd /bin/bash" and + * "no_keep_domain /usr/bin/passwd from <kernel> /usr/sbin/sshd /bin/bash" will + * cause "/usr/bin/passwd" to belong to + * "<kernel> /usr/sbin/sshd /bin/bash /usr/bin/passwd" domain, unless + * explicitly specified by "initialize_domain". + */ static LIST_HEAD(tomoyo_domain_keeper_list); static DECLARE_RWSEM(tomoyo_domain_keeper_list_lock); @@ -296,7 +440,6 @@ static int tomoyo_update_domain_keeper_entry(const char *domainname, struct tomoyo_domain_keeper_entry *ptr; const struct tomoyo_path_info *saved_domainname; const struct tomoyo_path_info *saved_program = NULL; - static DEFINE_MUTEX(lock); int error = -ENOMEM; bool is_last_name = false; @@ -315,7 +458,6 @@ static int tomoyo_update_domain_keeper_entry(const char *domainname, saved_domainname = tomoyo_save_name(domainname); if (!saved_domainname) return -ENOMEM; - /***** EXCLUSIVE SECTION START *****/ down_write(&tomoyo_domain_keeper_list_lock); list_for_each_entry(ptr, &tomoyo_domain_keeper_list, list) { if (ptr->is_not != is_not || @@ -341,7 +483,6 @@ static int tomoyo_update_domain_keeper_entry(const char *domainname, error = 0; out: up_write(&tomoyo_domain_keeper_list_lock); - /***** EXCLUSIVE SECTION END *****/ return error; } @@ -394,13 +535,12 @@ bool tomoyo_read_domain_keeper_policy(struct tomoyo_io_buffer *head) from = " from "; program = ptr->program->name; } - if (!tomoyo_io_printf(head, - "%s" TOMOYO_KEYWORD_KEEP_DOMAIN - "%s%s%s\n", no, program, from, - ptr->domainname->name)) { - done = false; + done = tomoyo_io_printf(head, + "%s" TOMOYO_KEYWORD_KEEP_DOMAIN + "%s%s%s\n", no, program, from, + ptr->domainname->name); + if (!done) break; - } } up_read(&tomoyo_domain_keeper_list_lock); return done; @@ -446,7 +586,36 @@ static bool tomoyo_is_domain_keeper(const struct tomoyo_path_info *domainname, return flag; } -/* The list for "struct tomoyo_alias_entry". */ +/* + * tomoyo_alias_list is used for holding list of symlink's pathnames which are + * allowed to be passed to an execve() request. Normally, the domainname which + * the current process will belong to after execve() succeeds is calculated + * using dereferenced pathnames. But some programs behave differently depending + * on the name passed to argv[0]. For busybox, calculating domainname using + * dereferenced pathnames will cause all programs in the busybox to belong to + * the same domain. Thus, TOMOYO provides a way to allow use of symlink's + * pathname for checking execve()'s permission and calculating domainname which + * the current process will belong to after execve() succeeds. + * + * An entry is added by + * + * # echo 'alias /bin/busybox /bin/cat' > \ + * /sys/kernel/security/tomoyo/exception_policy + * + * and is deleted by + * + * # echo 'delete alias /bin/busybox /bin/cat' > \ + * /sys/kernel/security/tomoyo/exception_policy + * + * and all entries are retrieved by + * + * # grep ^alias /sys/kernel/security/tomoyo/exception_policy + * + * In the example above, if /bin/cat is a symlink to /bin/busybox and execution + * of /bin/cat is requested, permission is checked for /bin/cat rather than + * /bin/busybox and domainname which the current process will belong to after + * execve() succeeds is calculated using /bin/cat rather than /bin/busybox . + */ static LIST_HEAD(tomoyo_alias_list); static DECLARE_RWSEM(tomoyo_alias_list_lock); @@ -476,7 +645,6 @@ static int tomoyo_update_alias_entry(const char *original_name, saved_aliased_name = tomoyo_save_name(aliased_name); if (!saved_original_name || !saved_aliased_name) return -ENOMEM; - /***** EXCLUSIVE SECTION START *****/ down_write(&tomoyo_alias_list_lock); list_for_each_entry(ptr, &tomoyo_alias_list, list) { if (ptr->original_name != saved_original_name || @@ -499,7 +667,6 @@ static int tomoyo_update_alias_entry(const char *original_name, error = 0; out: up_write(&tomoyo_alias_list_lock); - /***** EXCLUSIVE SECTION END *****/ return error; } @@ -522,12 +689,11 @@ bool tomoyo_read_alias_policy(struct tomoyo_io_buffer *head) ptr = list_entry(pos, struct tomoyo_alias_entry, list); if (ptr->is_deleted) continue; - if (!tomoyo_io_printf(head, TOMOYO_KEYWORD_ALIAS "%s %s\n", - ptr->original_name->name, - ptr->aliased_name->name)) { - done = false; + done = tomoyo_io_printf(head, TOMOYO_KEYWORD_ALIAS "%s %s\n", + ptr->original_name->name, + ptr->aliased_name->name); + if (!done) break; - } } up_read(&tomoyo_alias_list_lock); return done; @@ -567,7 +733,6 @@ int tomoyo_delete_domain(char *domainname) name.name = domainname; tomoyo_fill_path_info(&name); - /***** EXCLUSIVE SECTION START *****/ down_write(&tomoyo_domain_list_lock); /* Is there an active domain? */ list_for_each_entry(domain, &tomoyo_domain_list, list) { @@ -581,7 +746,6 @@ int tomoyo_delete_domain(char *domainname) break; } up_write(&tomoyo_domain_list_lock); - /***** EXCLUSIVE SECTION END *****/ return 0; } @@ -600,7 +764,6 @@ struct tomoyo_domain_info *tomoyo_find_or_assign_new_domain(const char * struct tomoyo_domain_info *domain = NULL; const struct tomoyo_path_info *saved_domainname; - /***** EXCLUSIVE SECTION START *****/ down_write(&tomoyo_domain_list_lock); domain = tomoyo_find_domain(domainname); if (domain) @@ -619,7 +782,6 @@ struct tomoyo_domain_info *tomoyo_find_or_assign_new_domain(const char * domain->domainname != saved_domainname) continue; flag = false; - /***** CRITICAL SECTION START *****/ read_lock(&tasklist_lock); for_each_process(p) { if (tomoyo_real_domain(p) != domain) @@ -628,7 +790,6 @@ struct tomoyo_domain_info *tomoyo_find_or_assign_new_domain(const char * break; } read_unlock(&tasklist_lock); - /***** CRITICAL SECTION END *****/ if (flag) continue; list_for_each_entry(ptr, &domain->acl_info_list, list) { @@ -651,7 +812,6 @@ struct tomoyo_domain_info *tomoyo_find_or_assign_new_domain(const char * } out: up_write(&tomoyo_domain_list_lock); - /***** EXCLUSIVE SECTION END *****/ return domain; } @@ -739,7 +899,7 @@ int tomoyo_find_next_domain(struct linux_binprm *bprm, } /* Check execute permission. */ - retval = tomoyo_check_exec_perm(old_domain, &r, tmp); + retval = tomoyo_check_exec_perm(old_domain, &r); if (retval < 0) goto out; diff --git a/security/tomoyo/file.c b/security/tomoyo/file.c index 2316da8..5ae3a57 100644 --- a/security/tomoyo/file.c +++ b/security/tomoyo/file.c @@ -14,21 +14,50 @@ #include "realpath.h" #define ACC_MODE(x) ("\000\004\002\006"[(x)&O_ACCMODE]) -/* Structure for "allow_read" keyword. */ +/* + * tomoyo_globally_readable_file_entry is a structure which is used for holding + * "allow_read" entries. + * It has following fields. + * + * (1) "list" which is linked to tomoyo_globally_readable_list . + * (2) "filename" is a pathname which is allowed to open(O_RDONLY). + * (3) "is_deleted" is a bool which is true if marked as deleted, false + * otherwise. + */ struct tomoyo_globally_readable_file_entry { struct list_head list; const struct tomoyo_path_info *filename; bool is_deleted; }; -/* Structure for "file_pattern" keyword. */ +/* + * tomoyo_pattern_entry is a structure which is used for holding + * "tomoyo_pattern_list" entries. + * It has following fields. + * + * (1) "list" which is linked to tomoyo_pattern_list . + * (2) "pattern" is a pathname pattern which is used for converting pathnames + * to pathname patterns during learning mode. + * (3) "is_deleted" is a bool which is true if marked as deleted, false + * otherwise. + */ struct tomoyo_pattern_entry { struct list_head list; const struct tomoyo_path_info *pattern; bool is_deleted; }; -/* Structure for "deny_rewrite" keyword. */ +/* + * tomoyo_no_rewrite_entry is a structure which is used for holding + * "deny_rewrite" entries. + * It has following fields. + * + * (1) "list" which is linked to tomoyo_no_rewrite_list . + * (2) "pattern" is a pathname which is by default not permitted to modify + * already existing content. + * (3) "is_deleted" is a bool which is true if marked as deleted, false + * otherwise. + */ struct tomoyo_no_rewrite_entry { struct list_head list; const struct tomoyo_path_info *pattern; @@ -141,7 +170,31 @@ static int tomoyo_update_single_path_acl(const u8 type, const char *filename, struct tomoyo_domain_info * const domain, const bool is_delete); -/* The list for "struct tomoyo_globally_readable_file_entry". */ +/* + * tomoyo_globally_readable_list is used for holding list of pathnames which + * are by default allowed to be open()ed for reading by any process. + * + * An entry is added by + * + * # echo 'allow_read /lib/libc-2.5.so' > \ + * /sys/kernel/security/tomoyo/exception_policy + * + * and is deleted by + * + * # echo 'delete allow_read /lib/libc-2.5.so' > \ + * /sys/kernel/security/tomoyo/exception_policy + * + * and all entries are retrieved by + * + * # grep ^allow_read /sys/kernel/security/tomoyo/exception_policy + * + * In the example above, any process is allowed to + * open("/lib/libc-2.5.so", O_RDONLY). + * One exception is, if the domain which current process belongs to is marked + * as "ignore_global_allow_read", current process can't do so unless explicitly + * given "allow_read /lib/libc-2.5.so" to the domain which current process + * belongs to. + */ static LIST_HEAD(tomoyo_globally_readable_list); static DECLARE_RWSEM(tomoyo_globally_readable_list_lock); @@ -166,7 +219,6 @@ static int tomoyo_update_globally_readable_entry(const char *filename, saved_filename = tomoyo_save_name(filename); if (!saved_filename) return -ENOMEM; - /***** EXCLUSIVE SECTION START *****/ down_write(&tomoyo_globally_readable_list_lock); list_for_each_entry(ptr, &tomoyo_globally_readable_list, list) { if (ptr->filename != saved_filename) @@ -187,7 +239,6 @@ static int tomoyo_update_globally_readable_entry(const char *filename, error = 0; out: up_write(&tomoyo_globally_readable_list_lock); - /***** EXCLUSIVE SECTION END *****/ return error; } @@ -249,17 +300,44 @@ bool tomoyo_read_globally_readable_policy(struct tomoyo_io_buffer *head) list); if (ptr->is_deleted) continue; - if (!tomoyo_io_printf(head, TOMOYO_KEYWORD_ALLOW_READ "%s\n", - ptr->filename->name)) { - done = false; + done = tomoyo_io_printf(head, TOMOYO_KEYWORD_ALLOW_READ "%s\n", + ptr->filename->name); + if (!done) break; - } } up_read(&tomoyo_globally_readable_list_lock); return done; } -/* The list for "struct tomoyo_pattern_entry". */ +/* tomoyo_pattern_list is used for holding list of pathnames which are used for + * converting pathnames to pathname patterns during learning mode. + * + * An entry is added by + * + * # echo 'file_pattern /proc/\$/mounts' > \ + * /sys/kernel/security/tomoyo/exception_policy + * + * and is deleted by + * + * # echo 'delete file_pattern /proc/\$/mounts' > \ + * /sys/kernel/security/tomoyo/exception_policy + * + * and all entries are retrieved by + * + * # grep ^file_pattern /sys/kernel/security/tomoyo/exception_policy + * + * In the example above, if a process which belongs to a domain which is in + * learning mode requested open("/proc/1/mounts", O_RDONLY), + * "allow_read /proc/\$/mounts" is automatically added to the domain which that + * process belongs to. + * + * It is not a desirable behavior that we have to use /proc/\$/ instead of + * /proc/self/ when current process needs to access only current process's + * information. As of now, LSM version of TOMOYO is using __d_path() for + * calculating pathname. Non LSM version of TOMOYO is using its own function + * which pretends as if /proc/self/ is not a symlink; so that we can forbid + * current process from accessing other process's information. + */ static LIST_HEAD(tomoyo_pattern_list); static DECLARE_RWSEM(tomoyo_pattern_list_lock); @@ -284,7 +362,6 @@ static int tomoyo_update_file_pattern_entry(const char *pattern, saved_pattern = tomoyo_save_name(pattern); if (!saved_pattern) return -ENOMEM; - /***** EXCLUSIVE SECTION START *****/ down_write(&tomoyo_pattern_list_lock); list_for_each_entry(ptr, &tomoyo_pattern_list, list) { if (saved_pattern != ptr->pattern) @@ -305,7 +382,6 @@ static int tomoyo_update_file_pattern_entry(const char *pattern, error = 0; out: up_write(&tomoyo_pattern_list_lock); - /***** EXCLUSIVE SECTION END *****/ return error; } @@ -373,17 +449,44 @@ bool tomoyo_read_file_pattern(struct tomoyo_io_buffer *head) ptr = list_entry(pos, struct tomoyo_pattern_entry, list); if (ptr->is_deleted) continue; - if (!tomoyo_io_printf(head, TOMOYO_KEYWORD_FILE_PATTERN "%s\n", - ptr->pattern->name)) { - done = false; + done = tomoyo_io_printf(head, TOMOYO_KEYWORD_FILE_PATTERN + "%s\n", ptr->pattern->name); + if (!done) break; - } } up_read(&tomoyo_pattern_list_lock); return done; } -/* The list for "struct tomoyo_no_rewrite_entry". */ +/* + * tomoyo_no_rewrite_list is used for holding list of pathnames which are by + * default forbidden to modify already written content of a file. + * + * An entry is added by + * + * # echo 'deny_rewrite /var/log/messages' > \ + * /sys/kernel/security/tomoyo/exception_policy + * + * and is deleted by + * + * # echo 'delete deny_rewrite /var/log/messages' > \ + * /sys/kernel/security/tomoyo/exception_policy + * + * and all entries are retrieved by + * + * # grep ^deny_rewrite /sys/kernel/security/tomoyo/exception_policy + * + * In the example above, if a process requested to rewrite /var/log/messages , + * the process can't rewrite unless the domain which that process belongs to + * has "allow_rewrite /var/log/messages" entry. + * + * It is not a desirable behavior that we have to add "\040(deleted)" suffix + * when we want to allow rewriting already unlink()ed file. As of now, + * LSM version of TOMOYO is using __d_path() for calculating pathname. + * Non LSM version of TOMOYO is using its own function which doesn't append + * " (deleted)" suffix if the file is already unlink()ed; so that we don't + * need to worry whether the file is already unlink()ed or not. + */ static LIST_HEAD(tomoyo_no_rewrite_list); static DECLARE_RWSEM(tomoyo_no_rewrite_list_lock); @@ -407,7 +510,6 @@ static int tomoyo_update_no_rewrite_entry(const char *pattern, saved_pattern = tomoyo_save_name(pattern); if (!saved_pattern) return -ENOMEM; - /***** EXCLUSIVE SECTION START *****/ down_write(&tomoyo_no_rewrite_list_lock); list_for_each_entry(ptr, &tomoyo_no_rewrite_list, list) { if (ptr->pattern != saved_pattern) @@ -428,7 +530,6 @@ static int tomoyo_update_no_rewrite_entry(const char *pattern, error = 0; out: up_write(&tomoyo_no_rewrite_list_lock); - /***** EXCLUSIVE SECTION END *****/ return error; } @@ -489,11 +590,10 @@ bool tomoyo_read_no_rewrite_policy(struct tomoyo_io_buffer *head) ptr = list_entry(pos, struct tomoyo_no_rewrite_entry, list); if (ptr->is_deleted) continue; - if (!tomoyo_io_printf(head, TOMOYO_KEYWORD_DENY_REWRITE "%s\n", - ptr->pattern->name)) { - done = false; + done = tomoyo_io_printf(head, TOMOYO_KEYWORD_DENY_REWRITE + "%s\n", ptr->pattern->name); + if (!done) break; - } } up_read(&tomoyo_no_rewrite_list_lock); return done; @@ -745,7 +845,6 @@ static int tomoyo_update_single_path_acl(const u8 type, const char *filename, saved_filename = tomoyo_save_name(filename); if (!saved_filename) return -ENOMEM; - /***** EXCLUSIVE SECTION START *****/ down_write(&tomoyo_domain_acl_info_list_lock); if (is_delete) goto delete; @@ -800,7 +899,6 @@ static int tomoyo_update_single_path_acl(const u8 type, const char *filename, } out: up_write(&tomoyo_domain_acl_info_list_lock); - /***** EXCLUSIVE SECTION END *****/ return error; } @@ -836,7 +934,6 @@ static int tomoyo_update_double_path_acl(const u8 type, const char *filename1, saved_filename2 = tomoyo_save_name(filename2); if (!saved_filename1 || !saved_filename2) return -ENOMEM; - /***** EXCLUSIVE SECTION START *****/ down_write(&tomoyo_domain_acl_info_list_lock); if (is_delete) goto delete; @@ -884,7 +981,6 @@ static int tomoyo_update_double_path_acl(const u8 type, const char *filename1, } out: up_write(&tomoyo_domain_acl_info_list_lock); - /***** EXCLUSIVE SECTION END *****/ return error; } @@ -1025,13 +1121,11 @@ int tomoyo_check_file_perm(struct tomoyo_domain_info *domain, * * @domain: Pointer to "struct tomoyo_domain_info". * @filename: Check permission for "execute". - * @tmp: Buffer for temporary use. * * Returns 0 on success, negativevalue otherwise. */ int tomoyo_check_exec_perm(struct tomoyo_domain_info *domain, - const struct tomoyo_path_info *filename, - struct tomoyo_page_buffer *tmp) + const struct tomoyo_path_info *filename) { const u8 mode = tomoyo_check_flags(domain, TOMOYO_MAC_FOR_FILE); diff --git a/security/tomoyo/realpath.c b/security/tomoyo/realpath.c index 40927a8..5f2e332 100644 --- a/security/tomoyo/realpath.c +++ b/security/tomoyo/realpath.c @@ -220,7 +220,6 @@ void *tomoyo_alloc_element(const unsigned int size) = roundup(size, max(sizeof(void *), sizeof(long))); if (word_aligned_size > PATH_MAX) return NULL; - /***** EXCLUSIVE SECTION START *****/ mutex_lock(&lock); if (buf_used_len + word_aligned_size > PATH_MAX) { if (!tomoyo_quota_for_elements || @@ -251,7 +250,6 @@ void *tomoyo_alloc_element(const unsigned int size) } } mutex_unlock(&lock); - /***** EXCLUSIVE SECTION END *****/ return ptr; } @@ -267,7 +265,16 @@ static unsigned int tomoyo_quota_for_savename; */ #define TOMOYO_MAX_HASH 256 -/* Structure for string data. */ +/* + * tomoyo_name_entry is a structure which is used for linking + * "struct tomoyo_path_info" into tomoyo_name_list . + * + * Since tomoyo_name_list manages a list of strings which are shared by + * multiple processes (whereas "struct tomoyo_path_info" inside + * "struct tomoyo_path_info_with_data" is not shared), a reference counter will + * be added to "struct tomoyo_name_entry" rather than "struct tomoyo_path_info" + * when TOMOYO starts supporting garbage collector. + */ struct tomoyo_name_entry { struct list_head list; struct tomoyo_path_info entry; @@ -281,10 +288,10 @@ struct tomoyo_free_memory_block_list { }; /* - * The list for "struct tomoyo_name_entry". - * - * This list is updated only inside tomoyo_save_name(), thus - * no global mutex exists. + * tomoyo_name_list is used for holding string data used by TOMOYO. + * Since same string data is likely used for multiple times (e.g. + * "/lib/libc-2.5.so"), TOMOYO shares string data in the form of + * "const struct tomoyo_path_info *". */ static struct list_head tomoyo_name_list[TOMOYO_MAX_HASH]; @@ -318,7 +325,6 @@ const struct tomoyo_path_info *tomoyo_save_name(const char *name) return NULL; } hash = full_name_hash((const unsigned char *) name, len - 1); - /***** EXCLUSIVE SECTION START *****/ mutex_lock(&lock); list_for_each_entry(ptr, &tomoyo_name_list[hash % TOMOYO_MAX_HASH], list) { @@ -366,7 +372,6 @@ const struct tomoyo_path_info *tomoyo_save_name(const char *name) } out: mutex_unlock(&lock); - /***** EXCLUSIVE SECTION END *****/ return ptr ? &ptr->entry : NULL; } diff --git a/security/tomoyo/tomoyo.c b/security/tomoyo/tomoyo.c index e42be5c..3194d09 100644 --- a/security/tomoyo/tomoyo.c +++ b/security/tomoyo/tomoyo.c @@ -262,6 +262,10 @@ static int tomoyo_dentry_open(struct file *f, const struct cred *cred) return tomoyo_check_open_permission(tomoyo_domain(), &f->f_path, flags); } +/* + * tomoyo_security_ops is a "struct security_operations" which is used for + * registering TOMOYO. + */ static struct security_operations tomoyo_security_ops = { .name = "tomoyo", .cred_prepare = tomoyo_cred_prepare, diff --git a/security/tomoyo/tomoyo.h b/security/tomoyo/tomoyo.h index 41c6eba..0fd588a 100644 --- a/security/tomoyo/tomoyo.h +++ b/security/tomoyo/tomoyo.h @@ -17,13 +17,11 @@ struct path; struct inode; struct linux_binprm; struct pt_regs; -struct tomoyo_page_buffer; int tomoyo_check_file_perm(struct tomoyo_domain_info *domain, const char *filename, const u8 perm); int tomoyo_check_exec_perm(struct tomoyo_domain_info *domain, - const struct tomoyo_path_info *filename, - struct tomoyo_page_buffer *buf); + const struct tomoyo_path_info *filename); int tomoyo_check_open_permission(struct tomoyo_domain_info *domain, struct path *path, const int flag); int tomoyo_check_1path_perm(struct tomoyo_domain_info *domain, @@ -90,17 +88,10 @@ static inline struct tomoyo_domain_info *tomoyo_domain(void) return current_cred()->security; } -/* Caller holds tasklist_lock spinlock. */ static inline struct tomoyo_domain_info *tomoyo_real_domain(struct task_struct *task) { - /***** CRITICAL SECTION START *****/ - const struct cred *cred = get_task_cred(task); - struct tomoyo_domain_info *domain = cred->security; - - put_cred(cred); - return domain; - /***** CRITICAL SECTION END *****/ + return task_cred_xxx(task, security); } #endif /* !defined(_SECURITY_TOMOYO_TOMOYO_H) */ |
