summaryrefslogtreecommitdiffstats
path: root/sys/kern/sys_capability.c
Commit message (Collapse)AuthorAgeFilesLines
* MFC r280130:bdrewery2016-06-271-1/+1
| | | | cred: add proc_set_cred helper
* Merge r263233 from HEAD to stable/10:rwatson2015-03-191-1/+1
| | | | | | | | | Update kernel inclusions of capability.h to use capsicum.h instead; some further refinement is required as some device drivers intended to be portable over FreeBSD versions rely on __FreeBSD_version to decide whether to include capability.h. Sponsored by: Google, Inc.
* MFC r269023,r272503,r272505,r272523,r272567,r272569,r272574mjg2014-10-141-6/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Prepare fget_unlocked for reading fd table only once. Some capsicum functions accept fdp + fd and lookup fde based on that. Add variants which accept fde. =============================== Add sequence counters with memory barriers. Current implementation is somewhat simplistic and hackish, will be improved later after possible memory barrier overhaul. =============================== Plug capability races. fp and appropriate capability lookups were not atomic, which could result in improper capabilities being checked. This could result either in protection bypass or in a spurious ENOTCAPABLE. Make fp + capability check atomic with the help of sequence counters. =============================== Put and #ifdef _KERNEL around the #include for opt_capsicum.h to hopefully allow the build to finish after r272505. =============================== filedesc: fix up breakage introduced in 272505 Include sequence counter supports incoditionally [1]. This fixes reprted build problems with e.g. nvidia driver due to missing opt_capsicum.h. Replace fishy looking sizeof with offsetof. Make fde_seq the last member in order to simplify calculations. =============================== Keep struct filedescent comments within 80-char limit. =============================== seq_t needs to be visible to userspace
* This looks like a typo that breaks the build. Yell at me if this isn't thesbruno2013-09-051-1/+1
| | | | intended declaration.
* Change the cap_rights_t type from uint64_t to a structure that we can extendpjd2013-09-051-94/+76
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | in the future in a backward compatible (API and ABI) way. The cap_rights_t represents capability rights. We used to use one bit to represent one right, but we are running out of spare bits. Currently the new structure provides place for 114 rights (so 50 more than the previous cap_rights_t), but it is possible to grow the structure to hold at least 285 rights, although we can make it even larger if 285 rights won't be enough. The structure definition looks like this: struct cap_rights { uint64_t cr_rights[CAP_RIGHTS_VERSION + 2]; }; The initial CAP_RIGHTS_VERSION is 0. The top two bits in the first element of the cr_rights[] array contain total number of elements in the array - 2. This means if those two bits are equal to 0, we have 2 array elements. The top two bits in all remaining array elements should be 0. The next five bits in all array elements contain array index. Only one bit is used and bit position in this five-bits range defines array index. This means there can be at most five array elements in the future. To define new right the CAPRIGHT() macro must be used. The macro takes two arguments - an array index and a bit to set, eg. #define CAP_PDKILL CAPRIGHT(1, 0x0000000000000800ULL) We still support aliases that combine few rights, but the rights have to belong to the same array element, eg: #define CAP_LOOKUP CAPRIGHT(0, 0x0000000000000400ULL) #define CAP_FCHMOD CAPRIGHT(0, 0x0000000000002000ULL) #define CAP_FCHMODAT (CAP_FCHMOD | CAP_LOOKUP) There is new API to manage the new cap_rights_t structure: cap_rights_t *cap_rights_init(cap_rights_t *rights, ...); void cap_rights_set(cap_rights_t *rights, ...); void cap_rights_clear(cap_rights_t *rights, ...); bool cap_rights_is_set(const cap_rights_t *rights, ...); bool cap_rights_is_valid(const cap_rights_t *rights); void cap_rights_merge(cap_rights_t *dst, const cap_rights_t *src); void cap_rights_remove(cap_rights_t *dst, const cap_rights_t *src); bool cap_rights_contains(const cap_rights_t *big, const cap_rights_t *little); Capability rights to the cap_rights_init(), cap_rights_set(), cap_rights_clear() and cap_rights_is_set() functions are provided by separating them with commas, eg: cap_rights_t rights; cap_rights_init(&rights, CAP_READ, CAP_WRITE, CAP_FSTAT); There is no need to terminate the list of rights, as those functions are actually macros that take care of the termination, eg: #define cap_rights_set(rights, ...) \ __cap_rights_set((rights), __VA_ARGS__, 0ULL) void __cap_rights_set(cap_rights_t *rights, ...); Thanks to using one bit as an array index we can assert in those functions that there are no two rights belonging to different array elements provided together. For example this is illegal and will be detected, because CAP_LOOKUP belongs to element 0 and CAP_PDKILL to element 1: cap_rights_init(&rights, CAP_LOOKUP | CAP_PDKILL); Providing several rights that belongs to the same array's element this way is correct, but is not advised. It should only be used for aliases definition. This commit also breaks compatibility with some existing Capsicum system calls, but I see no other way to do that. This should be fine as Capsicum is still experimental and this change is not going to 9.x. Sponsored by: The FreeBSD Foundation
* Implement 32bit versions of the cap_ioctls_limit(2) and cap_ioctls_get(2)pjd2013-08-181-21/+30
| | | | | | | system calls as unsigned longs have different size on i386 and amd64. Reported by: jilles Sponsored by: The FreeBSD Foundation
* Use proper malloc type for ioctls white-list.pjd2013-05-231-5/+7
| | | | | Reported by: pho Tested by: pho
* Merge Capsicum overhaul:pjd2013-03-021-295/+350
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Capability is no longer separate descriptor type. Now every descriptor has set of its own capability rights. - The cap_new(2) system call is left, but it is no longer documented and should not be used in new code. - The new syscall cap_rights_limit(2) should be used instead of cap_new(2), which limits capability rights of the given descriptor without creating a new one. - The cap_getrights(2) syscall is renamed to cap_rights_get(2). - If CAP_IOCTL capability right is present we can further reduce allowed ioctls list with the new cap_ioctls_limit(2) syscall. List of allowed ioctls can be retrived with cap_ioctls_get(2) syscall. - If CAP_FCNTL capability right is present we can further reduce fcntls that can be used with the new cap_fcntls_limit(2) syscall and retrive them with cap_fcntls_get(2). - To support ioctl and fcntl white-listing the filedesc structure was heavly modified. - The audit subsystem, kdump and procstat tools were updated to recognize new syscalls. - Capability rights were revised and eventhough I tried hard to provide backward API and ABI compatibility there are some incompatible changes that are described in detail below: CAP_CREATE old behaviour: - Allow for openat(2)+O_CREAT. - Allow for linkat(2). - Allow for symlinkat(2). CAP_CREATE new behaviour: - Allow for openat(2)+O_CREAT. Added CAP_LINKAT: - Allow for linkat(2). ABI: Reuses CAP_RMDIR bit. - Allow to be target for renameat(2). Added CAP_SYMLINKAT: - Allow for symlinkat(2). Removed CAP_DELETE. Old behaviour: - Allow for unlinkat(2) when removing non-directory object. - Allow to be source for renameat(2). Removed CAP_RMDIR. Old behaviour: - Allow for unlinkat(2) when removing directory. Added CAP_RENAMEAT: - Required for source directory for the renameat(2) syscall. Added CAP_UNLINKAT (effectively it replaces CAP_DELETE and CAP_RMDIR): - Allow for unlinkat(2) on any object. - Required if target of renameat(2) exists and will be removed by this call. Removed CAP_MAPEXEC. CAP_MMAP old behaviour: - Allow for mmap(2) with any combination of PROT_NONE, PROT_READ and PROT_WRITE. CAP_MMAP new behaviour: - Allow for mmap(2)+PROT_NONE. Added CAP_MMAP_R: - Allow for mmap(PROT_READ). Added CAP_MMAP_W: - Allow for mmap(PROT_WRITE). Added CAP_MMAP_X: - Allow for mmap(PROT_EXEC). Added CAP_MMAP_RW: - Allow for mmap(PROT_READ | PROT_WRITE). Added CAP_MMAP_RX: - Allow for mmap(PROT_READ | PROT_EXEC). Added CAP_MMAP_WX: - Allow for mmap(PROT_WRITE | PROT_EXEC). Added CAP_MMAP_RWX: - Allow for mmap(PROT_READ | PROT_WRITE | PROT_EXEC). Renamed CAP_MKDIR to CAP_MKDIRAT. Renamed CAP_MKFIFO to CAP_MKFIFOAT. Renamed CAP_MKNODE to CAP_MKNODEAT. CAP_READ old behaviour: - Allow pread(2). - Disallow read(2), readv(2) (if there is no CAP_SEEK). CAP_READ new behaviour: - Allow read(2), readv(2). - Disallow pread(2) (CAP_SEEK was also required). CAP_WRITE old behaviour: - Allow pwrite(2). - Disallow write(2), writev(2) (if there is no CAP_SEEK). CAP_WRITE new behaviour: - Allow write(2), writev(2). - Disallow pwrite(2) (CAP_SEEK was also required). Added convinient defines: #define CAP_PREAD (CAP_SEEK | CAP_READ) #define CAP_PWRITE (CAP_SEEK | CAP_WRITE) #define CAP_MMAP_R (CAP_MMAP | CAP_SEEK | CAP_READ) #define CAP_MMAP_W (CAP_MMAP | CAP_SEEK | CAP_WRITE) #define CAP_MMAP_X (CAP_MMAP | CAP_SEEK | 0x0000000000000008ULL) #define CAP_MMAP_RW (CAP_MMAP_R | CAP_MMAP_W) #define CAP_MMAP_RX (CAP_MMAP_R | CAP_MMAP_X) #define CAP_MMAP_WX (CAP_MMAP_W | CAP_MMAP_X) #define CAP_MMAP_RWX (CAP_MMAP_R | CAP_MMAP_W | CAP_MMAP_X) #define CAP_RECV CAP_READ #define CAP_SEND CAP_WRITE #define CAP_SOCK_CLIENT \ (CAP_CONNECT | CAP_GETPEERNAME | CAP_GETSOCKNAME | CAP_GETSOCKOPT | \ CAP_PEELOFF | CAP_RECV | CAP_SEND | CAP_SETSOCKOPT | CAP_SHUTDOWN) #define CAP_SOCK_SERVER \ (CAP_ACCEPT | CAP_BIND | CAP_GETPEERNAME | CAP_GETSOCKNAME | \ CAP_GETSOCKOPT | CAP_LISTEN | CAP_PEELOFF | CAP_RECV | CAP_SEND | \ CAP_SETSOCKOPT | CAP_SHUTDOWN) Added defines for backward API compatibility: #define CAP_MAPEXEC CAP_MMAP_X #define CAP_DELETE CAP_UNLINKAT #define CAP_MKDIR CAP_MKDIRAT #define CAP_RMDIR CAP_UNLINKAT #define CAP_MKFIFO CAP_MKFIFOAT #define CAP_MKNOD CAP_MKNODAT #define CAP_SOCK_ALL (CAP_SOCK_CLIENT | CAP_SOCK_SERVER) Sponsored by: The FreeBSD Foundation Reviewed by: Christoph Mallon <christoph.mallon@gmx.de> Many aspects discussed with: rwatson, benl, jonathan ABI compatibility discussed with: kib
* Remove redundant parenthesis.pjd2013-02-171-1/+1
|
* Style: move opt_*.h includes in the proper place.pjd2012-06-101-3/+3
| | | | MFC after: 1 month
* Allways call fdrop().pho2012-03-121-5/+3
|
* Revisit the capability failure trace points. The initial implementationdes2011-10-181-2/+8
| | | | | | | | only logged instances where an operation on a file descriptor required capabilities which the file descriptor did not have. By adding a type enum to struct ktr_cap_fail, we can catch other types of capability failures as well, such as disallowed system calls or attempts to wrap a file descriptor with more capabilities than it had to begin with.
* Add a new trace point, KTRFAC_CAPFAIL, which traces capability checkdes2011-10-111-1/+9
| | | | failures. It is included in the default set for ktrace(1) and kdump(1).
* In order to maximize the re-usability of kernel code in user space thiskmacy2011-09-161-8/+8
| | | | | | | | | | | | | patch modifies makesyscalls.sh to prefix all of the non-compatibility calls (e.g. not linux_, freebsd32_) with sys_ and updates the kernel entry points and all places in the code that use them. It also fixes an additional name space collision between the kernel function psignal and the libc function of the same name by renaming the kernel psignal kern_psignal(). By introducing this change now we will ease future MFCs that change syscalls. Reviewed by: rwatson Approved by: re (bz)
* Add the fo_chown and fo_chmod methods to struct fileops and use themkib2011-08-161-0/+22
| | | | | | | | | | to implement fchown(2) and fchmod(2) support for several file types that previously lacked it. Add MAC entries for chown/chmod done on posix shared memory and (old) in-kernel posix semaphores. Based on the submission by: glebius Reviewed by: rwatson Approved by: re (bz)
* Update use of the FEATURE() macro in sys_capability.c to reflect the moverwatson2011-08-131-1/+3
| | | | | | to two different kernel options for capability mode vs. capabilities. Approved by: re (bz)
* Now that capability support has been committed, update and expand therwatson2011-08-131-3/+17
| | | | | | comment at the type of sys_capability.c to describe its new contents. Approved by: re (xxx)
* Allow Capsicum capabilities to delegate constrainedjonathan2011-08-131-9/+9
| | | | | | | | | | | | | | | | | access to file system subtrees to sandboxed processes. - Use of absolute paths and '..' are limited in capability mode. - Use of absolute paths and '..' are limited when looking up relative to a capability. - When a name lookup is performed, identify what operation is to be performed (such as CAP_MKDIR) as well as check for CAP_LOOKUP. With these constraints, openat() and friends are now safe in capability mode, and can then be used by code such as the capability-mode runtime linker. Approved by: re (bz), mentor (rwatson) Sponsored by: Google Inc
* Second-to-last commit implementing Capsicum capabilities in the FreeBSDrwatson2011-08-111-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | kernel for FreeBSD 9.0: Add a new capability mask argument to fget(9) and friends, allowing system call code to declare what capabilities are required when an integer file descriptor is converted into an in-kernel struct file *. With options CAPABILITIES compiled into the kernel, this enforces capability protection; without, this change is effectively a no-op. Some cases require special handling, such as mmap(2), which must preserve information about the maximum rights at the time of mapping in the memory map so that they can later be enforced in mprotect(2) -- this is done by narrowing the rights in the existing max_protection field used for similar purposes with file permissions. In namei(9), we assert that the code is not reached from within capability mode, as we're not yet ready to enforce namespace capabilities there. This will follow in a later commit. Update two capability names: CAP_EVENT and CAP_KEVENT become CAP_POST_KEVENT and CAP_POLL_KEVENT to more accurately indicate what they represent. Approved by: re (bz) Submitted by: jonathan Sponsored by: Google Inc
* Turn on AUDIT_ARG_RIGHTS() for cap_new(2).jonathan2011-07-221-2/+0
| | | | | | | | Now that the code is in place to audit capability method rights, start using it to audit the 'rights' argument to cap_new(2). Approved by: re (kib), mentor (rwatson) Sponsored by: Google Inc
* Add cap_new() and cap_getrights() system calls.jonathan2011-07-151-0/+67
| | | | | | | | | Implement two previously-reserved Capsicum system calls: - cap_new() creates a capability to wrap an existing file descriptor - cap_getrights() queries the rights mask of a capability. Approved by: mentor (rwatson), re (Capsicum blanket) Sponsored by: Google Inc
* Add implementation for capabilities.jonathan2011-07-151-4/+214
| | | | | | | | | | | | | | Code to actually implement Capsicum capabilities, including fileops and kern_capwrap(), which creates a capability to wrap an existing file descriptor. We also modify kern_close() and closef() to handle capabilities. Finally, remove cap_filelist from struct capability, since we don't actually need it. Approved by: mentor (rwatson), re (Capsicum blanket) Sponsored by: Google Inc
* Add kernel functions to unwrap capabilities.jonathan2011-07-041-0/+122
| | | | | | | | | | | | | | | cap_funwrap() and cap_funwrap_mmap() unwrap capabilities, exposing the underlying object. Attempting to unwrap a capability with an inadequate rights mask (e.g. calling cap_funwrap(fp, CAP_WRITE | CAP_MMAP, &result) on a capability whose rights mask is CAP_READ | CAP_MMAP) will result in ENOTCAPABLE. Unwrapping a non-capability is effectively a no-op. These functions will be used by Capsicum-aware versions of _fget(), etc. Approved by: mentor (rwatson), re (Capsicum blanket) Sponsored by: Google Inc
* We may split today's CAPABILITIES into CAPABILITY_MODE (which hasjonathan2011-06-291-4/+4
| | | | | | | | | | | | | to do with global namespaces) and CAPABILITIES (which has to do with constraining file descriptors). Just in case, and because it's a better name anyway, let's move CAPABILITIES out of the way. Also, change opt_capabilities.h to opt_capsicum.h; for now, this will only hold CAPABILITY_MODE, but it will probably also hold the new CAPABILITIES (implying constrained file descriptors) in the future. Approved by: rwatson Sponsored by: Google UK Ltd
* Remove redundant Capsicum sysctl.jonathan2011-06-251-7/+0
| | | | | | Since we're now declaring FEATURE(security_capabilities), there's no need for an explicit SYSCTL_NODE. Approved by: rwatson
* - Add a FEATURE for capsicum (security_capabilities).netchild2011-03-041-0/+2
| | | | | | - Rename mac FEATURE to security_mac. Discussed with: rwatson
* Add initial support for Capsicum's Capability Mode to the FreeBSD kernel,rwatson2011-03-011-0/+123
compiled conditionally on options CAPABILITIES: Add a new credential flag, CRED_FLAG_CAPMODE, which indicates that a subject (typically a process) is in capability mode. Add two new system calls, cap_enter(2) and cap_getmode(2), which allow setting and querying (but never clearing) the flag. Export the capability mode flag via process information sysctls. Sponsored by: Google, Inc. Reviewed by: anderson Discussed with: benl, kris, pjd Obtained from: Capsicum Project MFC after: 3 months
OpenPOWER on IntegriCloud