diff options
| author | Matthew Garrett <mjg59@google.com> | 2018-01-08 13:36:19 -0800 |
|---|---|---|
| committer | Mimi Zohar <zohar@linux.vnet.ibm.com> | 2018-03-23 06:31:11 -0400 |
| commit | 3ec30113264a7bcd389f51d1738e42da0f41bb5a (patch) | |
| tree | 75a1465c8f53522dafcf2d41085c925cb025e29f /security | |
| parent | 5893ed18a26d1f56b97c0290b0cbbc2d49d6de28 (diff) | |
| download | lwn-3ec30113264a7bcd389f51d1738e42da0f41bb5a.tar.gz lwn-3ec30113264a7bcd389f51d1738e42da0f41bb5a.zip | |
security: Add a cred_getsecid hook
For IMA purposes, we want to be able to obtain the prepared secid in the
bprm structure before the credentials are committed. Add a cred_getsecid
hook that makes this possible.
Signed-off-by: Matthew Garrett <mjg59@google.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Cc: Paul Moore <paul@paul-moore.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Diffstat (limited to 'security')
| -rw-r--r-- | security/security.c | 7 | ||||
| -rw-r--r-- | security/selinux/hooks.c | 6 | ||||
| -rw-r--r-- | security/smack/smack_lsm.c | 18 |
3 files changed, 31 insertions, 0 deletions
diff --git a/security/security.c b/security/security.c index 14c291910d25..957e8bee3554 100644 --- a/security/security.c +++ b/security/security.c @@ -1005,6 +1005,13 @@ void security_transfer_creds(struct cred *new, const struct cred *old) call_void_hook(cred_transfer, new, old); } +void security_cred_getsecid(const struct cred *c, u32 *secid) +{ + *secid = 0; + call_void_hook(cred_getsecid, c, secid); +} +EXPORT_SYMBOL(security_cred_getsecid); + int security_kernel_act_as(struct cred *new, u32 secid) { return call_int_hook(kernel_act_as, 0, new, secid); diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 8abd542c6b7c..b7d4473edbde 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -3844,6 +3844,11 @@ static void selinux_cred_transfer(struct cred *new, const struct cred *old) *tsec = *old_tsec; } +static void selinux_cred_getsecid(const struct cred *c, u32 *secid) +{ + *secid = cred_sid(c); +} + /* * set the security data for a kernel service * - all the creation contexts are set to unlabelled @@ -6482,6 +6487,7 @@ static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = { LSM_HOOK_INIT(cred_free, selinux_cred_free), LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare), LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer), + LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid), LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as), LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as), LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request), diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index feada2665322..ed20d36c1149 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -2050,6 +2050,23 @@ static void smack_cred_transfer(struct cred *new, const struct cred *old) } /** + * smack_cred_getsecid - get the secid corresponding to a creds structure + * @c: the object creds + * @secid: where to put the result + * + * Sets the secid to contain a u32 version of the smack label. + */ +static void smack_cred_getsecid(const struct cred *c, u32 *secid) +{ + struct smack_known *skp; + + rcu_read_lock(); + skp = smk_of_task(c->security); + *secid = skp->smk_secid; + rcu_read_unlock(); +} + +/** * smack_kernel_act_as - Set the subjective context in a set of credentials * @new: points to the set of credentials to be modified. * @secid: specifies the security ID to be set @@ -4733,6 +4750,7 @@ static struct security_hook_list smack_hooks[] __lsm_ro_after_init = { LSM_HOOK_INIT(cred_free, smack_cred_free), LSM_HOOK_INIT(cred_prepare, smack_cred_prepare), LSM_HOOK_INIT(cred_transfer, smack_cred_transfer), + LSM_HOOK_INIT(cred_getsecid, smack_cred_getsecid), LSM_HOOK_INIT(kernel_act_as, smack_kernel_act_as), LSM_HOOK_INIT(kernel_create_files_as, smack_kernel_create_files_as), LSM_HOOK_INIT(task_setpgid, smack_task_setpgid), |