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* TOMOYO: Avoid race when retrying "file execute" permission check.Tetsuo Handa2011-09-141-34/+22
| | | | | | | | | | | | | There was a race window that the pathname which is subjected to "file execute" permission check when retrying via supervisor's decision because the pathname was recalculated upon retry. Though, there is an inevitable race window even without supervisor, for we have to calculate the symbolic link's pathname from "struct linux_binprm"->filename rather than from "struct linux_binprm"->file because we cannot back calculate the symbolic link's pathname from the dereferenced pathname. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* TOMOYO: Allow domain transition without execve().Tetsuo Handa2011-09-144-28/+210
| | | | | | | | | | | | | | To be able to split permissions for Apache's CGI programs which are executed without execve(), add special domain transition which is performed by writing a TOMOYO's domainname to /sys/kernel/security/tomoyo/self_domain interface. This is an API for TOMOYO-aware userland applications. However, since I expect TOMOYO and other LSM modules to run in parallel, this patch does not use /proc/self/attr/ interface in order to avoid conflicts with other LSM modules when it became possible to run multiple LSM modules in parallel. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* TOMOYO: Allow controlling generation of access granted logs for per an entry ↵Tetsuo Handa2011-09-145-1/+38
| | | | | | | | | | | | | | | basis. Add per-entry flag which controls generation of grant logs because Xen and KVM issues ioctl requests so frequently. For example, file ioctl /dev/null 0x5401 grant_log=no will suppress /sys/kernel/security/tomoyo/audit even if preference says grant_log=yes . Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* TOMOYO: Add socket operation restriction support.Tetsuo Handa2011-09-1410-17/+1215
| | | | | | | | This patch adds support for permission checks for PF_INET/PF_INET6/PF_UNIX socket's bind()/listen()/connect()/send() operations. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* TOMOYO: Add environment variable name restriction support.Tetsuo Handa2011-09-147-10/+266
| | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds support for checking environment variable's names. Although TOMOYO already provides ability to check argv[]/envp[] passed to execve() requests, file execute /bin/sh exec.envp["LD_LIBRARY_PATH"]="bar" will reject execution of /bin/sh if environment variable LD_LIBRARY_PATH is not defined. To grant execution of /bin/sh if LD_LIBRARY_PATH is not defined, administrators have to specify like file execute /bin/sh exec.envp["LD_LIBRARY_PATH"]="/system/lib" file execute /bin/sh exec.envp["LD_LIBRARY_PATH"]=NULL . Since there are many environment variables whereas conditional checks are applied as "&&", it is difficult to cover all combinations. Therefore, this patch supports conditional checks that are applied as "||", by specifying like file execute /bin/sh misc env LD_LIBRARY_PATH exec.envp["LD_LIBRARY_PATH"]="/system/lib" which means "grant execution of /bin/sh if environment variable is not defined or is defined and its value is /system/lib". Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* security: sparse fix: Move security_fixup_op to security.hJames Morris2011-09-091-3/+0
| | | | | | Fix sparse warning by moving declaraion to global header. Signed-off-by: James Morris <jmorris@namei.org>
* selinux: sparse fix: fix several warnings in the security server codeJames Morris2011-09-095-7/+9
| | | | | | Fix several sparse warnings in the SELinux security server code. Signed-off-by: James Morris <jmorris@namei.org>
* selinux: sparse fix: include selinux.h in exports.cJames Morris2011-09-091-0/+1
| | | | | | | Fix warning: security/selinux/exports.c:18:6: warning: symbol 'selinux_is_enabled' was not declared. Should it be static? Signed-off-by: James Morris <jmorris@namei.org>
* selinux: sparse fix: fix warnings in netlink codeJames Morris2011-09-096-5/+6
| | | | | | Fix sparse warnings in SELinux Netlink code. Signed-off-by: James Morris <jmorris@namei.org>
* selinux: sparse fix: eliminate warnings for selinuxfsJames Morris2011-09-093-6/+4
| | | | | | Fixes several sparse warnings for selinuxfs.c Signed-off-by: James Morris <jmorris@namei.org>
* ima: sparse fix: include linux/ima.h in ima_main.cJames Morris2011-09-091-0/+1
| | | | | | | | | | Fixes sparse warnings: security/integrity/ima/ima_main.c:105:6: warning: symbol 'ima_file_free' was not declared. Should it be static? security/integrity/ima/ima_main.c:167:5: warning: symbol 'ima_file_mmap' was not declared. Should it be static? security/integrity/ima/ima_main.c:192:5: warning: symbol 'ima_bprm_check' was not declared. Should it be static? security/integrity/ima/ima_main.c:211:5: warning: symbol 'ima_file_check' was not declared. Should it be static? Signed-off-by: James Morris <jmorris@namei.org>
* ima: sparse fix: make ima_open_policy staticJames Morris2011-09-091-1/+1
| | | | | | | Fixes sparse warning: security/integrity/ima/ima_fs.c:290:5: warning: symbol 'ima_open_policy' was not declared. Should it be static? Signed-off-by: James Morris <jmorris@namei.org>
* apparmor: sparse fix: include procattr.h in procattr.cJames Morris2011-09-091-0/+1
| | | | | | | | | | | Fix sparse warnings: security/apparmor/procattr.c:35:5: warning: symbol 'aa_getprocattr' was not declared. Should it be static? security/apparmor/procattr.c:113:5: warning: symbol 'aa_setprocattr_changehat' was not declared. Should it be static? security/apparmor/procattr.c:158:5: warning: symbol 'aa_setprocattr_changeprofile' was not declared. Should it be static? security/apparmor/procattr.c:166:5: warning: symbol 'aa_setprocattr_permipc' was not declared. Should it be static? Signed-off-by: James Morris <jmorris@namei.org> Acked-by: John Johansen <john.johansen@canonical.com>
* apparmor: sparse fix: rename shadowed variables in policy_unpack.cJames Morris2011-09-091-6/+6
| | | | | | | | | | | | Fix the following warnings: security/apparmor/policy_unpack.c:384:35: warning: symbol 'size' shadows an earlier one security/apparmor/policy_unpack.c:370:24: originally declared here security/apparmor/policy_unpack.c:443:29: warning: symbol 'tmp' shadows an earlier one security/apparmor/policy_unpack.c:434:21: originally declared here Signed-off-by: James Morris <jmorris@namei.org> Acked-by: John Johansen <john.johansen@canonical.com>
* apparmor: sparse fix: add apparmor.h to lib.cJames Morris2011-09-091-0/+1
| | | | | | | | | | Fix the following sparse warnings: security/apparmor/lib.c:37:6: warning: symbol 'aa_split_fqname' was not declared. Should it be static? security/apparmor/lib.c:63:6: warning: symbol 'aa_info_message' was not declared. Should it be static? security/apparmor/lib.c:83:6: warning: symbol 'kvmalloc' was not declared. Should it be static? security/apparmor/lib.c:123:6: warning: symbol 'kvfree' was not declared. Should it be static? Signed-off-by: James Morris <jmorris@namei.org>
* apparmor: sparse fix: include ipc.hJames Morris2011-09-091-0/+1
| | | | | | | | | | Include ipc.h to eliminate sparse warnings. security/apparmor/ipc.c:61:5: warning: symbol 'aa_may_ptrace' was not declared. Should it be static? security/apparmor/ipc.c:83:5: warning: symbol 'aa_ptrace' was not declared. Should it be static Signed-off-by: James Morris <jmorris@namei.org> Acked-by: John Johansen <john.johansen@canonical.com>
* selinux: sparse fix: declare selinux_disable() in security.hJames Morris2011-09-092-1/+1
| | | | | | Sparse fix: declare selinux_disable() in security.h Signed-off-by: James Morris <jmorris@namei.org>
* selinux: sparse fix: move selinux_complete_initJames Morris2011-09-092-1/+1
| | | | | | Sparse fix: move selinux_complete_init Signed-off-by: James Morris <jmorris@namei.org>
* selinux: sparse fix: make selinux_secmark_refcount staticJames Morris2011-09-091-1/+1
| | | | | | Sparse fix: make selinux_secmark_refcount static. Signed-off-by: James Morris <jmorris@namei.org>
* apparmor: sparse fix: make aa_create_aafs staticJames Morris2011-09-091-1/+1
| | | | | | | Sparse fix: make aa_create_aafs static. Signed-off-by: James Morris <jmorris@namei.org> Acked-by: John Johansen <john.johansen@canonical.com>
* integrity: sparse fix: move iint_initialized to integrity.hJames Morris2011-09-092-1/+3
| | | | | | Sparse fix: move iint_initialized to integrity.h Signed-off-by: James Morris <jmorris@namei.org>
* TOMOYO: Fix incorrect enforce mode.Tetsuo Handa2011-09-091-1/+2
| | | | | | | | | In tomoyo_get_mode() since 2.6.36, CONFIG::file::execute was by error used in place of CONFIG::file if CONFIG::file::execute was set to other than default. As a result, enforcing mode was not applied in a way documentation says. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* KEYS: Correctly destroy key payloads when their keytype is removedDavid Howells2011-08-233-208/+258
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | unregister_key_type() has code to mark a key as dead and make it unavailable in one loop and then destroy all those unavailable key payloads in the next loop. However, the loop to mark keys dead renders the key undetectable to the second loop by changing the key type pointer also. Fix this by the following means: (1) The key code has two garbage collectors: one deletes unreferenced keys and the other alters keyrings to delete links to old dead, revoked and expired keys. They can end up holding each other up as both want to scan the key serial tree under spinlock. Combine these into a single routine. (2) Move the dead key marking, dead link removal and dead key removal into the garbage collector as a three phase process running over the three cycles of the normal garbage collection procedure. This is tracked by the KEY_GC_REAPING_DEAD_1, _2 and _3 state flags. unregister_key_type() then just unlinks the key type from the list, wakes up the garbage collector and waits for the third phase to complete. (3) Downgrade the key types sem in unregister_key_type() once it has deleted the key type from the list so that it doesn't block the keyctl() syscall. (4) Dead keys that cannot be simply removed in the third phase have their payloads destroyed with the key's semaphore write-locked to prevent interference by the keyctl() syscall. There should be no in-kernel users of dead keys of that type by the point of unregistration, though keyctl() may be holding a reference. (5) Only perform timer recalculation in the GC if the timer actually expired. If it didn't, we'll get another cycle when it goes off - and if the key that actually triggered it has been removed, it's not a problem. (6) Only garbage collect link if the timer expired or if we're doing dead key clean up phase 2. (7) As only key_garbage_collector() is permitted to use rb_erase() on the key serial tree, it doesn't need to revalidate its cursor after dropping the spinlock as the node the cursor points to must still exist in the tree. (8) Drop the spinlock in the GC if there is contention on it or if we need to reschedule. After dealing with that, get the spinlock again and resume scanning. This has been tested in the following ways: (1) Run the keyutils testsuite against it. (2) Using the AF_RXRPC and RxKAD modules to test keytype removal: Load the rxrpc_s key type: # insmod /tmp/af-rxrpc.ko # insmod /tmp/rxkad.ko Create a key (http://people.redhat.com/~dhowells/rxrpc/listen.c): # /tmp/listen & [1] 8173 Find the key: # grep rxrpc_s /proc/keys 091086e1 I--Q-- 1 perm 39390000 0 0 rxrpc_s 52:2 Link it to a session keyring, preferably one with a higher serial number: # keyctl link 0x20e36251 @s Kill the process (the key should remain as it's linked to another place): # fg /tmp/listen ^C Remove the key type: rmmod rxkad rmmod af-rxrpc This can be made a more effective test by altering the following part of the patch: if (unlikely(gc_state & KEY_GC_REAPING_DEAD_2)) { /* Make sure everyone revalidates their keys if we marked a * bunch as being dead and make sure all keyring ex-payloads * are destroyed. */ kdebug("dead sync"); synchronize_rcu(); To call synchronize_rcu() in GC phase 1 instead. That causes that the keyring's old payload content to hang around longer until it's RCU destroyed - which usually happens after GC phase 3 is complete. This allows the destroy_dead_key branch to be tested. Reported-by: Benjamin Coddington <bcodding@gmail.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* KEYS: The dead key link reaper should be non-reentrantDavid Howells2011-08-231-3/+3
| | | | | | | | | The dead key link reaper should be non-reentrant as it relies on global state to keep track of where it's got to when it returns to the work queue manager to give it some air. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* KEYS: Make the key reaper non-reentrantDavid Howells2011-08-231-1/+1
| | | | | | | | | | | Make the key reaper non-reentrant by sticking it on the appropriate system work queue when we queue it. This will allow it to have global state and drop locks. It should probably be non-reentrant already as it may spend a long time holding the key serial spinlock, and so multiple entrants can spend long periods of time just sitting there spinning, waiting to get the lock. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* KEYS: Move the unreferenced key reaper to the keys garbage collector fileDavid Howells2011-08-233-76/+85
| | | | | | | | Move the unreferenced key reaper function to the keys garbage collector file as that's a more appropriate place with the dead key link reaper. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* KEYS: __key_link() should use the RCU deref wrapper for keyring payloadsDavid Howells2011-08-231-2/+1
| | | | | | | | | __key_link() should use the RCU deref wrapper rcu_dereference_locked_keyring() for accessing keyring payloads rather than calling rcu_dereference_protected() directly. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* KEYS: keyctl_get_keyring_ID() should create a session keyring if create flag setDavid Howells2011-08-231-2/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The keyctl call: keyctl_get_keyring_ID(KEY_SPEC_SESSION_KEYRING, 1) should create a session keyring if the process doesn't have one of its own because the create flag argument is set - rather than subscribing to and returning the user-session keyring as: keyctl_get_keyring_ID(KEY_SPEC_SESSION_KEYRING, 0) will do. This can be tested by commenting out pam_keyinit in the /etc/pam.d files and running the following program a couple of times in a row: #include <stdio.h> #include <stdlib.h> #include <keyutils.h> int main(int argc, char *argv[]) { key_serial_t uk, usk, sk, nsk; uk = keyctl_get_keyring_ID(KEY_SPEC_USER_KEYRING, 0); usk = keyctl_get_keyring_ID(KEY_SPEC_USER_SESSION_KEYRING, 0); sk = keyctl_get_keyring_ID(KEY_SPEC_SESSION_KEYRING, 0); nsk = keyctl_get_keyring_ID(KEY_SPEC_SESSION_KEYRING, 1); printf("keys: %08x %08x %08x %08x\n", uk, usk, sk, nsk); return 0; } Without this patch, I see: keys: 3975ddc7 119c0c66 119c0c66 119c0c66 keys: 3975ddc7 119c0c66 119c0c66 119c0c66 With this patch, I see: keys: 2cb4997b 34112878 34112878 17db2ce3 keys: 2cb4997b 34112878 34112878 39f3c73e As can be seen, the session keyring starts off the same as the user-session keyring each time, but with the patch a new session keyring is created when the create flag is set. Reported-by: Greg Wettstein <greg@enjellic.com> Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Greg Wettstein <greg@enjellic.com> Signed-off-by: James Morris <jmorris@namei.org>
* KEYS: If install_session_keyring() is given a keyring, it should install itDavid Howells2011-08-231-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If install_session_keyring() is given a keyring, it should install it rather than just creating a new one anyway. This was accidentally broken in: commit d84f4f992cbd76e8f39c488cf0c5d123843923b1 Author: David Howells <dhowells@redhat.com> Date: Fri Nov 14 10:39:23 2008 +1100 Subject: CRED: Inaugurate COW credentials The impact of that commit is that pam_keyinit no longer works correctly if 'force' isn't specified against a login process. This is because: keyctl_get_keyring_ID(KEY_SPEC_SESSION_KEYRING, 0) now always creates a new session keyring and thus the check whether the session keyring and the user-session keyring are the same is always false. This leads pam_keyinit to conclude that a session keyring is installed and it shouldn't be revoked by pam_keyinit here if 'revoke' is specified. Any system that specifies 'force' against pam_keyinit in the PAM configuration files for login methods (login, ssh, su -l, kdm, etc.) is not affected since that bypasses the broken check and forces the creation of a new session keyring anyway (for which the revoke flag is not cleared) - and any subsequent call to pam_keyinit really does have a session keyring already installed, and so the check works correctly there. Reverting to the previous behaviour will cause the kernel to subscribe the process to the user-session keyring as its session keyring if it doesn't have a session keyring of its own. pam_keyinit will detect this and install a new session keyring anyway (and won't clear the revert flag). This can be tested by commenting out pam_keyinit in the /etc/pam.d files and running the following program a couple of times in a row: #include <stdio.h> #include <stdlib.h> #include <keyutils.h> int main(int argc, char *argv[]) { key_serial_t uk, usk, sk; uk = keyctl_get_keyring_ID(KEY_SPEC_USER_KEYRING, 0); usk = keyctl_get_keyring_ID(KEY_SPEC_USER_SESSION_KEYRING, 0); sk = keyctl_get_keyring_ID(KEY_SPEC_SESSION_KEYRING, 0); printf("keys: %08x %08x %08x\n", uk, usk, sk); return 0; } Without the patch, I see: keys: 3884e281 24c4dfcf 22825f8e keys: 3884e281 24c4dfcf 068772be With the patch, I see: keys: 26be9c83 0e755ce0 0e755ce0 keys: 26be9c83 0e755ce0 0e755ce0 As can be seen, with the patch, the session keyring is the same as the user-session keyring each time; without the patch a new session keyring is generated each time. Reported-by: Greg Wettstein <greg@enjellic.com> Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Greg Wettstein <greg@enjellic.com> Signed-off-by: James Morris <jmorris@namei.org>
* evm: add Kconfig TCG_TPM dependencyMimi Zohar2011-08-181-1/+1
| | | | | | | | | | | | | | | Although the EVM encrypted-key should be encrypted/decrypted using a trusted-key, a user-defined key could be used instead. When using a user- defined key, a TCG_TPM dependency should not be required. Unfortunately, the encrypted-key code needs to be refactored a bit in order to remove this dependency. This patch adds the TCG_TPM dependency. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>, Randy Dunlap <rdunlap@xenotimenet> Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
* tomoyo: remove tomoyo_gc_thread()->daemonize()Oleg Nesterov2011-08-171-1/+1
| | | | | | | | | | | | daemonize() is only needed when a user-space task does kernel_thread(). tomoyo_gc_thread() is kthread_create()'ed and thus it doesn't need the soon-to-be-deprecated daemonize(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Matt Fleming <matt.fleming@intel.com> Signed-off-by: James Morris <jmorris@namei.org>
* capabilities: initialize has_capSerge Hallyn2011-08-161-1/+1
| | | | | | | | Initialize has_cap in cap_bprm_set_creds() Reported-by: Andrew G. Morgan <morgan@kernel.org> Signed-off-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: James Morris <jmorris@namei.org>
* capabilities: do not grant full privs for setuid w/ file caps + no effective ↵Zhi Li2011-08-121-6/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | caps A task (when !SECURE_NOROOT) which executes a setuid-root binary will obtain root privileges while executing that binary. If the binary also has effective capabilities set, then only those capabilities will be granted. The rationale is that the same binary can carry both setuid-root and the minimal file capability set, so that on a filesystem not supporting file caps the binary can still be executed with privilege, while on a filesystem supporting file caps it will run with minimal privilege. This special case currently does NOT happen if there are file capabilities but no effective capabilities. Since capability-aware programs can very well start with empty pE but populated pP and move those caps to pE when needed. In other words, if the file has file capabilities but NOT effective capabilities, then we should do the same thing as if there were file capabilities, and not grant full root privileges. This patchset does that. (Changelog by Serge Hallyn). Signed-off-by: Zhi Li <lizhi1215@gmail.com> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: James Morris <jmorris@namei.org>
* evm: fix evm_inode_init_security return codeMimi Zohar2011-08-111-1/+1
| | | | | | | | evm_inode_init_security() should return 0, when EVM is not enabled. (Returning an error is a remnant of evm_inode_post_init_security.) Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
* EVM: ensure trusted and encypted key symbols are available to EVMJames Morris2011-08-091-1/+3
| | | | | | | | | Select trusted and encrypted keys if EVM is selected, to ensure the requisite symbols are available. Otherwise, these can be selected as modules while EVM is static, leading to a kernel build failure. Signed-off-by: James Morris <jmorris@namei.org>
* Merge branch 'next-evm' of ↵James Morris2011-08-0919-209/+1089
|\ | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/zohar/ima-2.6 into next Conflicts: fs/attr.c Resolve conflict manually. Signed-off-by: James Morris <jmorris@namei.org>
| * evm: add evm_inode_setattr to prevent updating an invalid security.evmMimi Zohar2011-07-182-1/+21
| | | | | | | | | | | | | | Permit changing of security.evm only when valid, unless in fixmode. Reported-by: Roberto Sassu <roberto.sassu@polito.it> Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
| * evm: permit only valid security.evm xattrs to be updatedMimi Zohar2011-07-181-14/+63
| | | | | | | | | | | | | | | | | | | | | | | | | | In addition to requiring CAP_SYS_ADMIN permission to modify/delete security.evm, prohibit invalid security.evm xattrs from changing, unless in fixmode. This patch prevents inadvertent 'fixing' of security.evm to reflect offline modifications. Changelog v7: - rename boot paramater 'evm_mode' to 'evm' Reported-by: Roberto Sassu <roberto.sassu@polito.it> Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
| * evm: replace hmac_status with evm_statusDmitry Kasatkin2011-07-183-9/+9
| | | | | | | | | | | | | | We will use digital signatures in addtion to hmac. Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@nokia.com> Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
| * evm: evm_verify_hmac must not return INTEGRITY_UNKNOWNDmitry Kasatkin2011-07-181-6/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If EVM is not supported or enabled, evm_verify_hmac() returns INTEGRITY_UNKNOWN, which ima_appraise_measurement() ignores and sets the appraisal status based solely on the security.ima verification. evm_verify_hmac() also returns INTEGRITY_UNKNOWN for other failures, such as temporary failures like -ENOMEM, resulting in possible attack vectors. This patch changes the default return code for temporary/unexpected failures, like -ENOMEM, from INTEGRITY_UNKNOWN to INTEGRITY_FAIL, making evm_verify_hmac() fail safe. As a result, failures need to be re-evaluated in order to catch both temporary errors, such as the -ENOMEM, as well as errors that have been resolved in fix mode. Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@nokia.com> Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
| * evm: additional parameter to pass integrity cache entry 'iint'Dmitry Kasatkin2011-07-181-10/+8
| | | | | | | | | | | | | | Additional iint parameter allows to skip lookup in the cache. Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@nokia.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
| * evm: crypto hash replaced by shashDmitry Kasatkin2011-07-183-45/+57
| | | | | | | | | | | | | | | | | | | | | | | | Using shash is more efficient, because the algorithm is allocated only once. Only the descriptor to store the hash state needs to be allocated for every operation. Changelog v6: - check for crypto_shash_setkey failure Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@nokia.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
| * evm: call evm_inode_init_security from security_inode_init_securityMimi Zohar2011-07-181-6/+12
| | | | | | | | | | | | | | | | | | Changelog v7: - moved the initialization call to security_inode_init_security, renaming evm_inode_post_init_security to evm_inode_init_security - increase size of xattr array for EVM xattr Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
| * evm: add evm_inode_init_security to initialize new filesMimi Zohar2011-07-183-0/+61
| | | | | | | | | | | | | | | | | | | | | | | | | | Initialize 'security.evm' for new files. Changelog v7: - renamed evm_inode_post_init_security to evm_inode_init_security - moved struct xattr definition to earlier patch - allocate xattr name Changelog v6: - Use 'struct evm_ima_xattr_data' Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
| * security: imbed evm calls in security hooksMimi Zohar2011-07-182-2/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Imbed the evm calls evm_inode_setxattr(), evm_inode_post_setxattr(), evm_inode_removexattr() in the security hooks. evm_inode_setxattr() protects security.evm xattr. evm_inode_post_setxattr() and evm_inode_removexattr() updates the hmac associated with an inode. (Assumes an LSM module protects the setting/removing of xattr.) Changelog: - Don't define evm_verifyxattr(), unless CONFIG_INTEGRITY is enabled. - xattr_name is a 'const', value is 'void *' Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Acked-by: Serge Hallyn <serge.hallyn@ubuntu.com>
| * evm: add support for different security.evm data typesDmitry Kasatkin2011-07-183-9/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | EVM protects a file's security extended attributes(xattrs) against integrity attacks. The current patchset maintains an HMAC-sha1 value across the security xattrs, storing the value as the extended attribute 'security.evm'. We anticipate other methods for protecting the security extended attributes. This patch reserves the first byte of 'security.evm' as a place holder for the type of method. Changelog v6: - move evm_ima_xattr_type definition to security/integrity/integrity.h - defined a structure for the EVM xattr called evm_ima_xattr_data (based on Serge Hallyn's suggestion) - removed unnecessary memset Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@nokia.com> Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
| * evm: re-releaseMimi Zohar2011-07-1810-1/+632
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | EVM protects a file's security extended attributes(xattrs) against integrity attacks. This patchset provides the framework and an initial method. The initial method maintains an HMAC-sha1 value across the security extended attributes, storing the HMAC value as the extended attribute 'security.evm'. Other methods of validating the integrity of a file's metadata will be posted separately (eg. EVM-digital-signatures). While this patchset does authenticate the security xattrs, and cryptographically binds them to the inode, coming extensions will bind other directory and inode metadata for more complete protection. To help simplify the review and upstreaming process, each extension will be posted separately (eg. IMA-appraisal, IMA-appraisal-directory). For a general overview of the proposed Linux integrity subsystem, refer to Dave Safford's whitepaper: http://downloads.sf.net/project/linux-ima/linux-ima/Integrity_overview.pdf. EVM depends on the Kernel Key Retention System to provide it with a trusted/encrypted key for the HMAC-sha1 operation. The key is loaded onto the root's keyring using keyctl. Until EVM receives notification that the key has been successfully loaded onto the keyring (echo 1 > <securityfs>/evm), EVM can not create or validate the 'security.evm' xattr, but returns INTEGRITY_UNKNOWN. Loading the key and signaling EVM should be done as early as possible. Normally this is done in the initramfs, which has already been measured as part of the trusted boot. For more information on creating and loading existing trusted/encrypted keys, refer to Documentation/keys-trusted-encrypted.txt. A sample dracut patch, which loads the trusted/encrypted key and enables EVM, is available from http://linux-ima.sourceforge.net/#EVM. Based on the LSMs enabled, the set of EVM protected security xattrs is defined at compile. EVM adds the following three calls to the existing security hooks: evm_inode_setxattr(), evm_inode_post_setxattr(), and evm_inode_removexattr. To initialize and update the 'security.evm' extended attribute, EVM defines three calls: evm_inode_post_init(), evm_inode_post_setattr() and evm_inode_post_removexattr() hooks. To verify the integrity of a security xattr, EVM exports evm_verifyxattr(). Changelog v7: - Fixed URL in EVM ABI documentation Changelog v6: (based on Serge Hallyn's review) - fix URL in patch description - remove evm_hmac_size definition - use SHA1_DIGEST_SIZE (removed both MAX_DIGEST_SIZE and evm_hmac_size) - moved linux include before other includes - test for crypto_hash_setkey failure - fail earlier for invalid key - clear entire encrypted key, even on failure - check xattr name length before comparing xattr names Changelog: - locking based on i_mutex, remove evm_mutex - using trusted/encrypted keys for storing the EVM key used in the HMAC-sha1 operation. - replaced crypto hash with shash (Dmitry Kasatkin) - support for additional methods of verifying the security xattrs (Dmitry Kasatkin) - iint not allocated for all regular files, but only for those appraised - Use cap_sys_admin in lieu of cap_mac_admin - Use __vfs_setxattr_noperm(), without permission checks, from EVM Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
| * integrity: move ima inode integrity data managementMimi Zohar2011-07-1813-203/+247
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move the inode integrity data(iint) management up to the integrity directory in order to share the iint among the different integrity models. Changelog: - don't define MAX_DIGEST_SIZE - rename several globally visible 'ima_' prefixed functions, structs, locks, etc to 'integrity_' - replace '20' with SHA1_DIGEST_SIZE - reflect location change in appropriate Kconfig and Makefiles - remove unnecessary initialization of iint_initialized to 0 - rebased on current ima_iint.c - define integrity_iint_store/lock as static There should be no other functional changes. Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Acked-by: Serge Hallyn <serge.hallyn@ubuntu.com>
| * security: new security_inode_init_security API adds function callbackMimi Zohar2011-07-181-3/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch changes the security_inode_init_security API by adding a filesystem specific callback to write security extended attributes. This change is in preparation for supporting the initialization of multiple LSM xattrs and the EVM xattr. Initially the callback function walks an array of xattrs, writing each xattr separately, but could be optimized to write multiple xattrs at once. For existing security_inode_init_security() calls, which have not yet been converted to use the new callback function, such as those in reiserfs and ocfs2, this patch defines security_old_inode_init_security(). Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
* | doc: Update the email address for Paul Moore in various source filesPaul Moore2011-08-0116-16/+16
| | | | | | | | | | | | | | | | | | | | My @hp.com will no longer be valid starting August 5, 2011 so an update is necessary. My new email address is employer independent so we don't have to worry about doing this again any time soon. Signed-off-by: Paul Moore <paul.moore@hp.com> Signed-off-by: Paul Moore <paul@paul-moore.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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