diff options
Diffstat (limited to 'include/linux/lsm_hooks.h')
| -rw-r--r-- | include/linux/lsm_hooks.h | 50 |
1 files changed, 28 insertions, 22 deletions
diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h index 988ca0df7824..c719af37df20 100644 --- a/include/linux/lsm_hooks.h +++ b/include/linux/lsm_hooks.h @@ -34,40 +34,46 @@ * * Security hooks for program execution operations. * + * @bprm_creds_for_exec: + * If the setup in prepare_exec_creds did not setup @bprm->cred->security + * properly for executing @bprm->file, update the LSM's portion of + * @bprm->cred->security to be what commit_creds needs to install for the + * new program. This hook may also optionally check permissions + * (e.g. for transitions between security domains). + * The hook must set @bprm->secureexec to 1 if AT_SECURE should be set to + * request libc enable secure mode. + * @bprm contains the linux_binprm structure. + * Return 0 if the hook is successful and permission is granted. * @bprm_set_creds: - * Save security information in the bprm->security field, typically based - * on information about the bprm->file, for later use by the apply_creds - * hook. This hook may also optionally check permissions (e.g. for + * Assuming that the relevant bits of @bprm->cred->security have been + * previously set, examine @bprm->file and regenerate them. This is + * so that the credentials derived from the interpreter the code is + * actually going to run are used rather than credentials derived + * from a script. This done because the interpreter binary needs to + * reopen script, and may end up opening something completely different. + * This hook may also optionally check permissions (e.g. for * transitions between security domains). - * This hook may be called multiple times during a single execve, e.g. for - * interpreters. The hook can tell whether it has already been called by - * checking to see if @bprm->security is non-NULL. If so, then the hook - * may decide either to retain the security information saved earlier or - * to replace it. The hook must set @bprm->secureexec to 1 if a "secure - * exec" has happened as a result of this hook call. The flag is used to - * indicate the need for a sanitized execution environment, and is also - * passed in the ELF auxiliary table on the initial stack to indicate - * whether libc should enable secure mode. + * The hook must set @bprm->cap_elevated to 1 if AT_SECURE should be set to + * request libc enable secure mode. * @bprm contains the linux_binprm structure. * Return 0 if the hook is successful and permission is granted. * @bprm_check_security: * This hook mediates the point when a search for a binary handler will - * begin. It allows a check the @bprm->security value which is set in the - * preceding set_creds call. The primary difference from set_creds is - * that the argv list and envp list are reliably available in @bprm. This - * hook may be called multiple times during a single execve; and in each - * pass set_creds is called first. + * begin. It allows a check against the @bprm->cred->security value + * which was set in the preceding creds_for_exec call. The argv list and + * envp list are reliably available in @bprm. This hook may be called + * multiple times during a single execve. * @bprm contains the linux_binprm structure. * Return 0 if the hook is successful and permission is granted. * @bprm_committing_creds: * Prepare to install the new security attributes of a process being * transformed by an execve operation, based on the old credentials * pointed to by @current->cred and the information set in @bprm->cred by - * the bprm_set_creds hook. @bprm points to the linux_binprm structure. - * This hook is a good place to perform state changes on the process such - * as closing open file descriptors to which access will no longer be - * granted when the attributes are changed. This is called immediately - * before commit_creds(). + * the bprm_creds_for_exec hook. @bprm points to the linux_binprm + * structure. This hook is a good place to perform state changes on the + * process such as closing open file descriptors to which access will no + * longer be granted when the attributes are changed. This is called + * immediately before commit_creds(). * @bprm_committed_creds: * Tidy up after the installation of the new security attributes of a * process being transformed by an execve operation. The new credentials |