From fe7bb272ee72b5cc377e02b556d0d718d12bbede Mon Sep 17 00:00:00 2001 From: Casey Schaufler Date: Sat, 2 May 2015 15:10:53 -0700 Subject: [PATCH] LSM: Add the comment to lsm_hooks.h Add the large comment describing the content of the security_operations structure to lsm_hooks.h. This wasn't done in the previous (1/7) patch because it would have exceeded the mail list size limits. Signed-off-by: Casey Schaufler Acked-by: John Johansen Acked-by: Kees Cook Acked-by: Paul Moore Acked-by: Stephen Smalley Acked-by: Tetsuo Handa Signed-off-by: James Morris --- include/linux/lsm_hooks.h | 1279 +++++++++++++++++++++++++++++++++++++ 1 file changed, 1279 insertions(+) diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h index c60f81b2d18c..b4c91de510c2 100644 --- a/include/linux/lsm_hooks.h +++ b/include/linux/lsm_hooks.h @@ -31,6 +31,1285 @@ #ifdef CONFIG_SECURITY +/** + * struct security_operations - main security structure + * + * Security module identifier. + * + * @name: + * A string that acts as a unique identifier for the LSM with max number + * of characters = SECURITY_NAME_MAX. + * + * Security hooks for program execution operations. + * + * @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 + * 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. + * @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. + * @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(). + * @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 + * have, by this point, been set to @current->cred. @bprm points to the + * linux_binprm structure. This hook is a good place to perform state + * changes on the process such as clearing out non-inheritable signal + * state. This is called immediately after commit_creds(). + * @bprm_secureexec: + * Return a boolean value (0 or 1) indicating whether a "secure exec" + * is required. The flag is passed in the auxiliary table + * on the initial stack to the ELF interpreter to indicate whether libc + * should enable secure mode. + * @bprm contains the linux_binprm structure. + * + * Security hooks for filesystem operations. + * + * @sb_alloc_security: + * Allocate and attach a security structure to the sb->s_security field. + * The s_security field is initialized to NULL when the structure is + * allocated. + * @sb contains the super_block structure to be modified. + * Return 0 if operation was successful. + * @sb_free_security: + * Deallocate and clear the sb->s_security field. + * @sb contains the super_block structure to be modified. + * @sb_statfs: + * Check permission before obtaining filesystem statistics for the @mnt + * mountpoint. + * @dentry is a handle on the superblock for the filesystem. + * Return 0 if permission is granted. + * @sb_mount: + * Check permission before an object specified by @dev_name is mounted on + * the mount point named by @nd. For an ordinary mount, @dev_name + * identifies a device if the file system type requires a device. For a + * remount (@flags & MS_REMOUNT), @dev_name is irrelevant. For a + * loopback/bind mount (@flags & MS_BIND), @dev_name identifies the + * pathname of the object being mounted. + * @dev_name contains the name for object being mounted. + * @path contains the path for mount point object. + * @type contains the filesystem type. + * @flags contains the mount flags. + * @data contains the filesystem-specific data. + * Return 0 if permission is granted. + * @sb_copy_data: + * Allow mount option data to be copied prior to parsing by the filesystem, + * so that the security module can extract security-specific mount + * options cleanly (a filesystem may modify the data e.g. with strsep()). + * This also allows the original mount data to be stripped of security- + * specific options to avoid having to make filesystems aware of them. + * @type the type of filesystem being mounted. + * @orig the original mount data copied from userspace. + * @copy copied data which will be passed to the security module. + * Returns 0 if the copy was successful. + * @sb_remount: + * Extracts security system specific mount options and verifies no changes + * are being made to those options. + * @sb superblock being remounted + * @data contains the filesystem-specific data. + * Return 0 if permission is granted. + * @sb_umount: + * Check permission before the @mnt file system is unmounted. + * @mnt contains the mounted file system. + * @flags contains the unmount flags, e.g. MNT_FORCE. + * Return 0 if permission is granted. + * @sb_pivotroot: + * Check permission before pivoting the root filesystem. + * @old_path contains the path for the new location of the + * current root (put_old). + * @new_path contains the path for the new root (new_root). + * Return 0 if permission is granted. + * @sb_set_mnt_opts: + * Set the security relevant mount options used for a superblock + * @sb the superblock to set security mount options for + * @opts binary data structure containing all lsm mount data + * @sb_clone_mnt_opts: + * Copy all security options from a given superblock to another + * @oldsb old superblock which contain information to clone + * @newsb new superblock which needs filled in + * @sb_parse_opts_str: + * Parse a string of security data filling in the opts structure + * @options string containing all mount options known by the LSM + * @opts binary data structure usable by the LSM + * @dentry_init_security: + * Compute a context for a dentry as the inode is not yet available + * since NFSv4 has no label backed by an EA anyway. + * @dentry dentry to use in calculating the context. + * @mode mode used to determine resource type. + * @name name of the last path component used to create file + * @ctx pointer to place the pointer to the resulting context in. + * @ctxlen point to place the length of the resulting context. + * + * + * Security hooks for inode operations. + * + * @inode_alloc_security: + * Allocate and attach a security structure to @inode->i_security. The + * i_security field is initialized to NULL when the inode structure is + * allocated. + * @inode contains the inode structure. + * Return 0 if operation was successful. + * @inode_free_security: + * @inode contains the inode structure. + * Deallocate the inode security structure and set @inode->i_security to + * NULL. + * @inode_init_security: + * Obtain the security attribute name suffix and value to set on a newly + * created inode and set up the incore security field for the new inode. + * This hook is called by the fs code as part of the inode creation + * transaction and provides for atomic labeling of the inode, unlike + * the post_create/mkdir/... hooks called by the VFS. The hook function + * is expected to allocate the name and value via kmalloc, with the caller + * being responsible for calling kfree after using them. + * If the security module does not use security attributes or does + * not wish to put a security attribute on this particular inode, + * then it should return -EOPNOTSUPP to skip this processing. + * @inode contains the inode structure of the newly created inode. + * @dir contains the inode structure of the parent directory. + * @qstr contains the last path component of the new object + * @name will be set to the allocated name suffix (e.g. selinux). + * @value will be set to the allocated attribute value. + * @len will be set to the length of the value. + * Returns 0 if @name and @value have been successfully set, + * -EOPNOTSUPP if no security attribute is needed, or + * -ENOMEM on memory allocation failure. + * @inode_create: + * Check permission to create a regular file. + * @dir contains inode structure of the parent of the new file. + * @dentry contains the dentry structure for the file to be created. + * @mode contains the file mode of the file to be created. + * Return 0 if permission is granted. + * @inode_link: + * Check permission before creating a new hard link to a file. + * @old_dentry contains the dentry structure for an existing + * link to the file. + * @dir contains the inode structure of the parent directory + * of the new link. + * @new_dentry contains the dentry structure for the new link. + * Return 0 if permission is granted. + * @path_link: + * Check permission before creating a new hard link to a file. + * @old_dentry contains the dentry structure for an existing link + * to the file. + * @new_dir contains the path structure of the parent directory of + * the new link. + * @new_dentry contains the dentry structure for the new link. + * Return 0 if permission is granted. + * @inode_unlink: + * Check the permission to remove a hard link to a file. + * @dir contains the inode structure of parent directory of the file. + * @dentry contains the dentry structure for file to be unlinked. + * Return 0 if permission is granted. + * @path_unlink: + * Check the permission to remove a hard link to a file. + * @dir contains the path structure of parent directory of the file. + * @dentry contains the dentry structure for file to be unlinked. + * Return 0 if permission is granted. + * @inode_symlink: + * Check the permission to create a symbolic link to a file. + * @dir contains the inode structure of parent directory of + * the symbolic link. + * @dentry contains the dentry structure of the symbolic link. + * @old_name contains the pathname of file. + * Return 0 if permission is granted. + * @path_symlink: + * Check the permission to create a symbolic link to a file. + * @dir contains the path structure of parent directory of + * the symbolic link. + * @dentry contains the dentry structure of the symbolic link. + * @old_name contains the pathname of file. + * Return 0 if permission is granted. + * @inode_mkdir: + * Check permissions to create a new directory in the existing directory + * associated with inode structure @dir. + * @dir contains the inode structure of parent of the directory + * to be created. + * @dentry contains the dentry structure of new directory. + * @mode contains the mode of new directory. + * Return 0 if permission is granted. + * @path_mkdir: + * Check permissions to create a new directory in the existing directory + * associated with path structure @path. + * @dir contains the path structure of parent of the directory + * to be created. + * @dentry contains the dentry structure of new directory. + * @mode contains the mode of new directory. + * Return 0 if permission is granted. + * @inode_rmdir: + * Check the permission to remove a directory. + * @dir contains the inode structure of parent of the directory + * to be removed. + * @dentry contains the dentry structure of directory to be removed. + * Return 0 if permission is granted. + * @path_rmdir: + * Check the permission to remove a directory. + * @dir contains the path structure of parent of the directory to be + * removed. + * @dentry contains the dentry structure of directory to be removed. + * Return 0 if permission is granted. + * @inode_mknod: + * Check permissions when creating a special file (or a socket or a fifo + * file created via the mknod system call). Note that if mknod operation + * is being done for a regular file, then the create hook will be called + * and not this hook. + * @dir contains the inode structure of parent of the new file. + * @dentry contains the dentry structure of the new file. + * @mode contains the mode of the new file. + * @dev contains the device number. + * Return 0 if permission is granted. + * @path_mknod: + * Check permissions when creating a file. Note that this hook is called + * even if mknod operation is being done for a regular file. + * @dir contains the path structure of parent of the new file. + * @dentry contains the dentry structure of the new file. + * @mode contains the mode of the new file. + * @dev contains the undecoded device number. Use new_decode_dev() to get + * the decoded device number. + * Return 0 if permission is granted. + * @inode_rename: + * Check for permission to rename a file or directory. + * @old_dir contains the inode structure for parent of the old link. + * @old_dentry contains the dentry structure of the old link. + * @new_dir contains the inode structure for parent of the new link. + * @new_dentry contains the dentry structure of the new link. + * Return 0 if permission is granted. + * @path_rename: + * Check for permission to rename a file or directory. + * @old_dir contains the path structure for parent of the old link. + * @old_dentry contains the dentry structure of the old link. + * @new_dir contains the path structure for parent of the new link. + * @new_dentry contains the dentry structure of the new link. + * Return 0 if permission is granted. + * @path_chmod: + * Check for permission to change DAC's permission of a file or directory. + * @dentry contains the dentry structure. + * @mnt contains the vfsmnt structure. + * @mode contains DAC's mode. + * Return 0 if permission is granted. + * @path_chown: + * Check for permission to change owner/group of a file or directory. + * @path contains the path structure. + * @uid contains new owner's ID. + * @gid contains new group's ID. + * Return 0 if permission is granted. + * @path_chroot: + * Check for permission to change root directory. + * @path contains the path structure. + * Return 0 if permission is granted. + * @inode_readlink: + * Check the permission to read the symbolic link. + * @dentry contains the dentry structure for the file link. + * Return 0 if permission is granted. + * @inode_follow_link: + * Check permission to follow a symbolic link when looking up a pathname. + * @dentry contains the dentry structure for the link. + * @nd contains the nameidata structure for the parent directory. + * Return 0 if permission is granted. + * @inode_permission: + * Check permission before accessing an inode. This hook is called by the + * existing Linux permission function, so a security module can use it to + * provide additional checking for existing Linux permission checks. + * Notice that this hook is called when a file is opened (as well as many + * other operations), whereas the file_security_ops permission hook is + * called when the actual read/write operations are performed. + * @inode contains the inode structure to check. + * @mask contains the permission mask. + * Return 0 if permission is granted. + * @inode_setattr: + * Check permission before setting file attributes. Note that the kernel + * call to notify_change is performed from several locations, whenever + * file attributes change (such as when a file is truncated, chown/chmod + * operations, transferring disk quotas, etc). + * @dentry contains the dentry structure for the file. + * @attr is the iattr structure containing the new file attributes. + * Return 0 if permission is granted. + * @path_truncate: + * Check permission before truncating a file. + * @path contains the path structure for the file. + * Return 0 if permission is granted. + * @inode_getattr: + * Check permission before obtaining file attributes. + * @mnt is the vfsmount where the dentry was looked up + * @dentry contains the dentry structure for the file. + * Return 0 if permission is granted. + * @inode_setxattr: + * Check permission before setting the extended attributes + * @value identified by @name for @dentry. + * Return 0 if permission is granted. + * @inode_post_setxattr: + * Update inode security field after successful setxattr operation. + * @value identified by @name for @dentry. + * @inode_getxattr: + * Check permission before obtaining the extended attributes + * identified by @name for @dentry. + * Return 0 if permission is granted. + * @inode_listxattr: + * Check permission before obtaining the list of extended attribute + * names for @dentry. + * Return 0 if permission is granted. + * @inode_removexattr: + * Check permission before removing the extended attribute + * identified by @name for @dentry. + * Return 0 if permission is granted. + * @inode_getsecurity: + * Retrieve a copy of the extended attribute representation of the + * security label associated with @name for @inode via @buffer. Note that + * @name is the remainder of the attribute name after the security prefix + * has been removed. @alloc is used to specify of the call should return a + * value via the buffer or just the value length Return size of buffer on + * success. + * @inode_setsecurity: + * Set the security label associated with @name for @inode from the + * extended attribute value @value. @size indicates the size of the + * @value in bytes. @flags may be XATTR_CREATE, XATTR_REPLACE, or 0. + * Note that @name is the remainder of the attribute name after the + * security. prefix has been removed. + * Return 0 on success. + * @inode_listsecurity: + * Copy the extended attribute names for the security labels + * associated with @inode into @buffer. The maximum size of @buffer + * is specified by @buffer_size. @buffer may be NULL to request + * the size of the buffer required. + * Returns number of bytes used/required on success. + * @inode_need_killpriv: + * Called when an inode has been changed. + * @dentry is the dentry being changed. + * Return <0 on error to abort the inode change operation. + * Return 0 if inode_killpriv does not need to be called. + * Return >0 if inode_killpriv does need to be called. + * @inode_killpriv: + * The setuid bit is being removed. Remove similar security labels. + * Called with the dentry->d_inode->i_mutex held. + * @dentry is the dentry being changed. + * Return 0 on success. If error is returned, then the operation + * causing setuid bit removal is failed. + * @inode_getsecid: + * Get the secid associated with the node. + * @inode contains a pointer to the inode. + * @secid contains a pointer to the location where result will be saved. + * In case of failure, @secid will be set to zero. + * + * Security hooks for file operations + * + * @file_permission: + * Check file permissions before accessing an open file. This hook is + * called by various operations that read or write files. A security + * module can use this hook to perform additional checking on these + * operations, e.g. to revalidate permissions on use to support privilege + * bracketing or policy changes. Notice that this hook is used when the + * actual read/write operations are performed, whereas the + * inode_security_ops hook is called when a file is opened (as well as + * many other operations). + * Caveat: Although this hook can be used to revalidate permissions for + * various system call operations that read or write files, it does not + * address the revalidation of permissions for memory-mapped files. + * Security modules must handle this separately if they need such + * revalidation. + * @file contains the file structure being accessed. + * @mask contains the requested permissions. + * Return 0 if permission is granted. + * @file_alloc_security: + * Allocate and attach a security structure to the file->f_security field. + * The security field is initialized to NULL when the structure is first + * created. + * @file contains the file structure to secure. + * Return 0 if the hook is successful and permission is granted. + * @file_free_security: + * Deallocate and free any security structures stored in file->f_security. + * @file contains the file structure being modified. + * @file_ioctl: + * @file contains the file structure. + * @cmd contains the operation to perform. + * @arg contains the operational arguments. + * Check permission for an ioctl operation on @file. Note that @arg + * sometimes represents a user space pointer; in other cases, it may be a + * simple integer value. When @arg represents a user space pointer, it + * should never be used by the security module. + * Return 0 if permission is granted. + * @mmap_addr : + * Check permissions for a mmap operation at @addr. + * @addr contains virtual address that will be used for the operation. + * Return 0 if permission is granted. + * @mmap_file : + * Check permissions for a mmap operation. The @file may be NULL, e.g. + * if mapping anonymous memory. + * @file contains the file structure for file to map (may be NULL). + * @reqprot contains the protection requested by the application. + * @prot contains the protection that will be applied by the kernel. + * @flags contains the operational flags. + * Return 0 if permission is granted. + * @file_mprotect: + * Check permissions before changing memory access permissions. + * @vma contains the memory region to modify. + * @reqprot contains the protection requested by the application. + * @prot contains the protection that will be applied by the kernel. + * Return 0 if permission is granted. + * @file_lock: + * Check permission before performing file locking operations. + * Note: this hook mediates both flock and fcntl style locks. + * @file contains the file structure. + * @cmd contains the posix-translated lock operation to perform + * (e.g. F_RDLCK, F_WRLCK). + * Return 0 if permission is granted. + * @file_fcntl: + * Check permission before allowing the file operation specified by @cmd + * from being performed on the file @file. Note that @arg sometimes + * represents a user space pointer; in other cases, it may be a simple + * integer value. When @arg represents a user space pointer, it should + * never be used by the security module. + * @file contains the file structure. + * @cmd contains the operation to be performed. + * @arg contains the operational arguments. + * Return 0 if permission is granted. + * @file_set_fowner: + * Save owner security information (typically from current->security) in + * file->f_security for later use by the send_sigiotask hook. + * @file contains the file structure to update. + * Return 0 on success. + * @file_send_sigiotask: + * Check permission for the file owner @fown to send SIGIO or SIGURG to the + * process @tsk. Note that this hook is sometimes called from interrupt. + * Note that the fown_struct, @fown, is never outside the context of a + * struct file, so the file structure (and associated security information) + * can always be obtained: + * container_of(fown, struct file, f_owner) + * @tsk contains the structure of task receiving signal. + * @fown contains the file owner information. + * @sig is the signal that will be sent. When 0, kernel sends SIGIO. + * Return 0 if permission is granted. + * @file_receive: + * This hook allows security modules to control the ability of a process + * to receive an open file descriptor via socket IPC. + * @file contains the file structure being received. + * Return 0 if permission is granted. + * @file_open + * Save open-time permission checking state for later use upon + * file_permission, and recheck access if anything has changed + * since inode_permission. + * + * Security hooks for task operations. + * + * @task_create: + * Check permission before creating a child process. See the clone(2) + * manual page for definitions of the @clone_flags. + * @clone_flags contains the flags indicating what should be shared. + * Return 0 if permission is granted. + * @task_free: + * @task task being freed + * Handle release of task-related resources. (Note that this can be called + * from interrupt context.) + * @cred_alloc_blank: + * @cred points to the credentials. + * @gfp indicates the atomicity of any memory allocations. + * Only allocate sufficient memory and attach to @cred such that + * cred_transfer() will not get ENOMEM. + * @cred_free: + * @cred points to the credentials. + * Deallocate and clear the cred->security field in a set of credentials. + * @cred_prepare: + * @new points to the new credentials. + * @old points to the original credentials. + * @gfp indicates the atomicity of any memory allocations. + * Prepare a new set of credentials by copying the data from the old set. + * @cred_transfer: + * @new points to the new credentials. + * @old points to the original credentials. + * Transfer data from original creds to new creds + * @kernel_act_as: + * Set the credentials for a kernel service to act as (subjective context). + * @new points to the credentials to be modified. + * @secid specifies the security ID to be set + * The current task must be the one that nominated @secid. + * Return 0 if successful. + * @kernel_create_files_as: + * Set the file creation context in a set of credentials to be the same as + * the objective context of the specified inode. + * @new points to the credentials to be modified. + * @inode points to the inode to use as a reference. + * The current task must be the one that nominated @inode. + * Return 0 if successful. + * @kernel_fw_from_file: + * Load firmware from userspace (not called for built-in firmware). + * @file contains the file structure pointing to the file containing + * the firmware to load. This argument will be NULL if the firmware + * was loaded via the uevent-triggered blob-based interface exposed + * by CONFIG_FW_LOADER_USER_HELPER. + * @buf pointer to buffer containing firmware contents. + * @size length of the firmware contents. + * Return 0 if permission is granted. + * @kernel_module_request: + * Ability to trigger the kernel to automatically upcall to userspace for + * userspace to load a kernel module with the given name. + * @kmod_name name of the module requested by the kernel + * Return 0 if successful. + * @kernel_module_from_file: + * Load a kernel module from userspace. + * @file contains the file structure pointing to the file containing + * the kernel module to load. If the module is being loaded from a blob, + * this argument will be NULL. + * Return 0 if permission is granted. + * @task_fix_setuid: + * Update the module's state after setting one or more of the user + * identity attributes of the current process. The @flags parameter + * indicates which of the set*uid system calls invoked this hook. If + * @new is the set of credentials that will be installed. Modifications + * should be made to this rather than to @current->cred. + * @old is the set of credentials that are being replaces + * @flags contains one of the LSM_SETID_* values. + * Return 0 on success. + * @task_setpgid: + * Check permission before setting the process group identifier of the + * process @p to @pgid. + * @p contains the task_struct for process being modified. + * @pgid contains the new pgid. + * Return 0 if permission is granted. + * @task_getpgid: + * Check permission before getting the process group identifier of the + * process @p. + * @p contains the task_struct for the process. + * Return 0 if permission is granted. + * @task_getsid: + * Check permission before getting the session identifier of the process + * @p. + * @p contains the task_struct for the process. + * Return 0 if permission is granted. + * @task_getsecid: + * Retrieve the security identifier of the process @p. + * @p contains the task_struct for the process and place is into @secid. + * In case of failure, @secid will be set to zero. + * + * @task_setnice: + * Check permission before setting the nice value of @p to @nice. + * @p contains the task_struct of process. + * @nice contains the new nice value. + * Return 0 if permission is granted. + * @task_setioprio + * Check permission before setting the ioprio value of @p to @ioprio. + * @p contains the task_struct of process. + * @ioprio contains the new ioprio value + * Return 0 if permission is granted. + * @task_getioprio + * Check permission before getting the ioprio value of @p. + * @p contains the task_struct of process. + * Return 0 if permission is granted. + * @task_setrlimit: + * Check permission before setting the resource limits of the current + * process for @resource to @new_rlim. The old resource limit values can + * be examined by dereferencing (current->signal->rlim + resource). + * @resource contains the resource whose limit is being set. + * @new_rlim contains the new limits for @resource. + * Return 0 if permission is granted. + * @task_setscheduler: + * Check permission before setting scheduling policy and/or parameters of + * process @p based on @policy and @lp. + * @p contains the task_struct for process. + * @policy contains the scheduling policy. + * @lp contains the scheduling parameters. + * Return 0 if permission is granted. + * @task_getscheduler: + * Check permission before obtaining scheduling information for process + * @p. + * @p contains the task_struct for process. + * Return 0 if permission is granted. + * @task_movememory + * Check permission before moving memory owned by process @p. + * @p contains the task_struct for process. + * Return 0 if permission is granted. + * @task_kill: + * Check permission before sending signal @sig to @p. @info can be NULL, + * the constant 1, or a pointer to a siginfo structure. If @info is 1 or + * SI_FROMKERNEL(info) is true, then the signal should be viewed as coming + * from the kernel and should typically be permitted. + * SIGIO signals are handled separately by the send_sigiotask hook in + * file_security_ops. + * @p contains the task_struct for process. + * @info contains the signal information. + * @sig contains the signal value. + * @secid contains the sid of the process where the signal originated + * Return 0 if permission is granted. + * @task_wait: + * Check permission before allowing a process to reap a child process @p + * and collect its status information. + * @p contains the task_struct for process. + * Return 0 if permission is granted. + * @task_prctl: + * Check permission before performing a process control operation on the + * current process. + * @option contains the operation. + * @arg2 contains a argument. + * @arg3 contains a argument. + * @arg4 contains a argument. + * @arg5 contains a argument. + * Return -ENOSYS if no-one wanted to handle this op, any other value to + * cause prctl() to return immediately with that value. + * @task_to_inode: + * Set the security attributes for an inode based on an associated task's + * security attributes, e.g. for /proc/pid inodes. + * @p contains the task_struct for the task. + * @inode contains the inode structure for the inode. + * + * Security hooks for Netlink messaging. + * + * @netlink_send: + * Save security information for a netlink message so that permission + * checking can be performed when the message is processed. The security + * information can be saved using the eff_cap field of the + * netlink_skb_parms structure. Also may be used to provide fine + * grained control over message transmission. + * @sk associated sock of task sending the message. + * @skb contains the sk_buff structure for the netlink message. + * Return 0 if the information was successfully saved and message + * is allowed to be transmitted. + * + * Security hooks for Unix domain networking. + * + * @unix_stream_connect: + * Check permissions before establishing a Unix domain stream connection + * between @sock and @other. + * @sock contains the sock structure. + * @other contains the peer sock structure. + * @newsk contains the new sock structure. + * Return 0 if permission is granted. + * @unix_may_send: + * Check permissions before connecting or sending datagrams from @sock to + * @other. + * @sock contains the socket structure. + * @other contains the peer socket structure. + * Return 0 if permission is granted. + * + * The @unix_stream_connect and @unix_may_send hooks were necessary because + * Linux provides an alternative to the conventional file name space for Unix + * domain sockets. Whereas binding and connecting to sockets in the file name + * space is mediated by the typical file permissions (and caught by the mknod + * and permission hooks in inode_security_ops), binding and connecting to + * sockets in the abstract name space is completely unmediated. Sufficient + * control of Unix domain sockets in the abstract name space isn't possible + * using only the socket layer hooks, since we need to know the actual target + * socket, which is not looked up until we are inside the af_unix code. + * + * Security hooks for socket operations. + * + * @socket_create: + * Check permissions prior to creating a new socket. + * @family contains the requested protocol family. + * @type contains the requested communications type. + * @protocol contains the requested protocol. + * @kern set to 1 if a kernel socket. + * Return 0 if permission is granted. + * @socket_post_create: + * This hook allows a module to update or allocate a per-socket security + * structure. Note that the security field was not added directly to the + * socket structure, but rather, the socket security information is stored + * in the associated inode. Typically, the inode alloc_security hook will + * allocate and and attach security information to + * sock->inode->i_security. This hook may be used to update the + * sock->inode->i_security field with additional information that wasn't + * available when the inode was allocated. + * @sock contains the newly created socket structure. + * @family contains the requested protocol family. + * @type contains the requested communications type. + * @protocol contains the requested protocol. + * @kern set to 1 if a kernel socket. + * @socket_bind: + * Check permission before socket protocol layer bind operation is + * performed and the socket @sock is bound to the address specified in the + * @address parameter. + * @sock contains the socket structure. + * @address contains the address to bind to. + * @addrlen contains the length of address. + * Return 0 if permission is granted. + * @socket_connect: + * Check permission before socket protocol layer connect operation + * attempts to connect socket @sock to a remote address, @address. + * @sock contains the socket structure. + * @address contains the address of remote endpoint. + * @addrlen contains the length of address. + * Return 0 if permission is granted. + * @socket_listen: + * Check permission before socket protocol layer listen operation. + * @sock contains the socket structure. + * @backlog contains the maximum length for the pending connection queue. + * Return 0 if permission is granted. + * @socket_accept: + * Check permission before accepting a new connection. Note that the new + * socket, @newsock, has been created and some information copied to it, + * but the accept operation has not actually been performed. + * @sock contains the listening socket structure. + * @newsock contains the newly created server socket for connection. + * Return 0 if permission is granted. + * @socket_sendmsg: + * Check permission before transmitting a message to another socket. + * @sock contains the socket structure. + * @msg contains the message to be transmitted. + * @size contains the size of message. + * Return 0 if permission is granted. + * @socket_recvmsg: + * Check permission before receiving a message from a socket. + * @sock contains the socket structure. + * @msg contains the message structure. + * @size contains the size of message structure. + * @flags contains the operational flags. + * Return 0 if permission is granted. + * @socket_getsockname: + * Check permission before the local address (name) of the socket object + * @sock is retrieved. + * @sock contains the socket structure. + * Return 0 if permission is granted. + * @socket_getpeername: + * Check permission before the remote address (name) of a socket object + * @sock is retrieved. + * @sock contains the socket structure. + * Return 0 if permission is granted. + * @socket_getsockopt: + * Check permissions before retrieving the options associated with socket + * @sock. + * @sock contains the socket structure. + * @level contains the protocol level to retrieve option from. + * @optname contains the name of option to retrieve. + * Return 0 if permission is granted. + * @socket_setsockopt: + * Check permissions before setting the options associated with socket + * @sock. + * @sock contains the socket structure. + * @level contains the protocol level to set options for. + * @optname contains the name of the option to set. + * Return 0 if permission is granted. + * @socket_shutdown: + * Checks permission before all or part of a connection on the socket + * @sock is shut down. + * @sock contains the socket structure. + * @how contains the flag indicating how future sends and receives + * are handled. + * Return 0 if permission is granted. + * @socket_sock_rcv_skb: + * Check permissions on incoming network packets. This hook is distinct + * from Netfilter's IP input hooks since it is the first time that the + * incoming sk_buff @skb has been associated with a particular socket, @sk. + * Must not sleep inside this hook because some callers hold spinlocks. + * @sk contains the sock (not socket) associated with the incoming sk_buff. + * @skb contains the incoming network data. + * @socket_getpeersec_stream: + * This hook allows the security module to provide peer socket security + * state for unix or connected tcp sockets to userspace via getsockopt + * SO_GETPEERSEC. For tcp sockets this can be meaningful if the + * socket is associated with an ipsec SA. + * @sock is the local socket. + * @optval userspace memory where the security state is to be copied. + * @optlen userspace int where the module should copy the actual length + * of the security state. + * @len as input is the maximum length to copy to userspace provided + * by the caller. + * Return 0 if all is well, otherwise, typical getsockopt return + * values. + * @socket_getpeersec_dgram: + * This hook allows the security module to provide peer socket security + * state for udp sockets on a per-packet basis to userspace via + * getsockopt SO_GETPEERSEC. The application must first have indicated + * the IP_PASSSEC option via getsockopt. It can then retrieve the + * security state returned by this hook for a packet via the SCM_SECURITY + * ancillary message type. + * @skb is the skbuff for the packet being queried + * @secdata is a pointer to a buffer in which to copy the security data + * @seclen is the maximum length for @secdata + * Return 0 on success, error on failure. + * @sk_alloc_security: + * Allocate and attach a security structure to the sk->sk_security field, + * which is used to copy security attributes between local stream sockets. + * @sk_free_security: + * Deallocate security structure. + * @sk_clone_security: + * Clone/copy security structure. + * @sk_getsecid: + * Retrieve the LSM-specific secid for the sock to enable caching + * of network authorizations. + * @sock_graft: + * Sets the socket's isec sid to the sock's sid. + * @inet_conn_request: + * Sets the openreq's sid to socket's sid with MLS portion taken + * from peer sid. + * @inet_csk_clone: + * Sets the new child socket's sid to the openreq sid. + * @inet_conn_established: + * Sets the connection's peersid to the secmark on skb. + * @secmark_relabel_packet: + * check if the process should be allowed to relabel packets to + * the given secid + * @security_secmark_refcount_inc + * tells the LSM to increment the number of secmark labeling rules loaded + * @security_secmark_refcount_dec + * tells the LSM to decrement the number of secmark labeling rules loaded + * @req_classify_flow: + * Sets the flow's sid to the openreq sid. + * @tun_dev_alloc_security: + * This hook allows a module to allocate a security structure for a TUN + * device. + * @security pointer to a security structure pointer. + * Returns a zero on success, negative values on failure. + * @tun_dev_free_security: + * This hook allows a module to free the security structure for a TUN + * device. + * @security pointer to the TUN device's security structure + * @tun_dev_create: + * Check permissions prior to creating a new TUN device. + * @tun_dev_attach_queue: + * Check permissions prior to attaching to a TUN device queue. + * @security pointer to the TUN device's security structure. + * @tun_dev_attach: + * This hook can be used by the module to update any security state + * associated with the TUN device's sock structure. + * @sk contains the existing sock structure. + * @security pointer to the TUN device's security structure. + * @tun_dev_open: + * This hook can be used by the module to update any security state + * associated with the TUN device's security structure. + * @security pointer to the TUN devices's security structure. + * + * Security hooks for XFRM operations. + * + * @xfrm_policy_alloc_security: + * @ctxp is a pointer to the xfrm_sec_ctx being added to Security Policy + * Database used by the XFRM system. + * @sec_ctx contains the security context information being provided by + * the user-level policy update program (e.g., setkey). + * Allocate a security structure to the xp->security field; the security + * field is initialized to NULL when the xfrm_policy is allocated. + * Return 0 if operation was successful (memory to allocate, legal context) + * @gfp is to specify the context for the allocation + * @xfrm_policy_clone_security: + * @old_ctx contains an existing xfrm_sec_ctx. + * @new_ctxp contains a new xfrm_sec_ctx being cloned from old. + * Allocate a security structure in new_ctxp that contains the + * information from the old_ctx structure. + * Return 0 if operation was successful (memory to allocate). + * @xfrm_policy_free_security: + * @ctx contains the xfrm_sec_ctx + * Deallocate xp->security. + * @xfrm_policy_delete_security: + * @ctx contains the xfrm_sec_ctx. + * Authorize deletion of xp->security. + * @xfrm_state_alloc: + * @x contains the xfrm_state being added to the Security Association + * Database by the XFRM system. + * @sec_ctx contains the security context information being provided by + * the user-level SA generation program (e.g., setkey or racoon). + * Allocate a security structure to the x->security field; the security + * field is initialized to NULL when the xfrm_state is allocated. Set the + * context to correspond to sec_ctx. Return 0 if operation was successful + * (memory to allocate, legal context). + * @xfrm_state_alloc_acquire: + * @x contains the xfrm_state being added to the Security Association + * Database by the XFRM system. + * @polsec contains the policy's security context. + * @secid contains the secid from which to take the mls portion of the + * context. + * Allocate a security structure to the x->security field; the security + * field is initialized to NULL when the xfrm_state is allocated. Set the + * context to correspond to secid. Return 0 if operation was successful + * (memory to allocate, legal context). + * @xfrm_state_free_security: + * @x contains the xfrm_state. + * Deallocate x->security. + * @xfrm_state_delete_security: + * @x contains the xfrm_state. + * Authorize deletion of x->security. + * @xfrm_policy_lookup: + * @ctx contains the xfrm_sec_ctx for which the access control is being + * checked. + * @fl_secid contains the flow security label that is used to authorize + * access to the policy xp. + * @dir contains the direction of the flow (input or output). + * Check permission when a flow selects a xfrm_policy for processing + * XFRMs on a packet. The hook is called when selecting either a + * per-socket policy or a generic xfrm policy. + * Return 0 if permission is granted, -ESRCH otherwise, or -errno + * on other errors. + * @xfrm_state_pol_flow_match: + * @x contains the state to match. + * @xp contains the policy to check for a match. + * @fl contains the flow to check for a match. + * Return 1 if there is a match. + * @xfrm_decode_session: + * @skb points to skb to decode. + * @secid points to the flow key secid to set. + * @ckall says if all xfrms used should be checked for same secid. + * Return 0 if ckall is zero or all xfrms used have the same secid. + * + * Security hooks affecting all Key Management operations + * + * @key_alloc: + * Permit allocation of a key and assign security data. Note that key does + * not have a serial number assigned at this point. + * @key points to the key. + * @flags is the allocation flags + * Return 0 if permission is granted, -ve error otherwise. + * @key_free: + * Notification of destruction; free security data. + * @key points to the key. + * No return value. + * @key_permission: + * See whether a specific operational right is granted to a process on a + * key. + * @key_ref refers to the key (key pointer + possession attribute bit). + * @cred points to the credentials to provide the context against which to + * evaluate the security data on the key. + * @perm describes the combination of permissions required of this key. + * Return 0 if permission is granted, -ve error otherwise. + * @key_getsecurity: + * Get a textual representation of the security context attached to a key + * for the purposes of honouring KEYCTL_GETSECURITY. This function + * allocates the storage for the NUL-terminated string and the caller + * should free it. + * @key points to the key to be queried. + * @_buffer points to a pointer that should be set to point to the + * resulting string (if no label or an error occurs). + * Return the length of the string (including terminating NUL) or -ve if + * an error. + * May also return 0 (and a NULL buffer pointer) if there is no label. + * + * Security hooks affecting all System V IPC operations. + * + * @ipc_permission: + * Check permissions for access to IPC + * @ipcp contains the kernel IPC permission structure + * @flag contains the desired (requested) permission set + * Return 0 if permission is granted. + * @ipc_getsecid: + * Get the secid associated with the ipc object. + * @ipcp contains the kernel IPC permission structure. + * @secid contains a pointer to the location where result will be saved. + * In case of failure, @secid will be set to zero. + * + * Security hooks for individual messages held in System V IPC message queues + * @msg_msg_alloc_security: + * Allocate and attach a security structure to the msg->security field. + * The security field is initialized to NULL when the structure is first + * created. + * @msg contains the message structure to be modified. + * Return 0 if operation was successful and permission is granted. + * @msg_msg_free_security: + * Deallocate the security structure for this message. + * @msg contains the message structure to be modified. + * + * Security hooks for System V IPC Message Queues + * + * @msg_queue_alloc_security: + * Allocate and attach a security structure to the + * msq->q_perm.security field. The security field is initialized to + * NULL when the structure is first created. + * @msq contains the message queue structure to be modified. + * Return 0 if operation was successful and permission is granted. + * @msg_queue_free_security: + * Deallocate security structure for this message queue. + * @msq contains the message queue structure to be modified. + * @msg_queue_associate: + * Check permission when a message queue is requested through the + * msgget system call. This hook is only called when returning the + * message queue identifier for an existing message queue, not when a + * new message queue is created. + * @msq contains the message queue to act upon. + * @msqflg contains the operation control flags. + * Return 0 if permission is granted. + * @msg_queue_msgctl: + * Check permission when a message control operation specified by @cmd + * is to be performed on the message queue @msq. + * The @msq may be NULL, e.g. for IPC_INFO or MSG_INFO. + * @msq contains the message queue to act upon. May be NULL. + * @cmd contains the operation to be performed. + * Return 0 if permission is granted. + * @msg_queue_msgsnd: + * Check permission before a message, @msg, is enqueued on the message + * queue, @msq. + * @msq contains the message queue to send message to. + * @msg contains the message to be enqueued. + * @msqflg contains operational flags. + * Return 0 if permission is granted. + * @msg_queue_msgrcv: + * Check permission before a message, @msg, is removed from the message + * queue, @msq. The @target task structure contains a pointer to the + * process that will be receiving the message (not equal to the current + * process when inline receives are being performed). + * @msq contains the message queue to retrieve message from. + * @msg contains the message destination. + * @target contains the task structure for recipient process. + * @type contains the type of message requested. + * @mode contains the operational flags. + * Return 0 if permission is granted. + * + * Security hooks for System V Shared Memory Segments + * + * @shm_alloc_security: + * Allocate and attach a security structure to the shp->shm_perm.security + * field. The security field is initialized to NULL when the structure is + * first created. + * @shp contains the shared memory structure to be modified. + * Return 0 if operation was successful and permission is granted. + * @shm_free_security: + * Deallocate the security struct for this memory segment. + * @shp contains the shared memory structure to be modified. + * @shm_associate: + * Check permission when a shared memory region is requested through the + * shmget system call. This hook is only called when returning the shared + * memory region identifier for an existing region, not when a new shared + * memory region is created. + * @shp contains the shared memory structure to be modified. + * @shmflg contains the operation control flags. + * Return 0 if permission is granted. + * @shm_shmctl: + * Check permission when a shared memory control operation specified by + * @cmd is to be performed on the shared memory region @shp. + * The @shp may be NULL, e.g. for IPC_INFO or SHM_INFO. + * @shp contains shared memory structure to be modified. + * @cmd contains the operation to be performed. + * Return 0 if permission is granted. + * @shm_shmat: + * Check permissions prior to allowing the shmat system call to attach the + * shared memory segment @shp to the data segment of the calling process. + * The attaching address is specified by @shmaddr. + * @shp contains the shared memory structure to be modified. + * @shmaddr contains the address to attach memory region to. + * @shmflg contains the operational flags. + * Return 0 if permission is granted. + * + * Security hooks for System V Semaphores + * + * @sem_alloc_security: + * Allocate and attach a security structure to the sma->sem_perm.security + * field. The security field is initialized to NULL when the structure is + * first created. + * @sma contains the semaphore structure + * Return 0 if operation was successful and permission is granted. + * @sem_free_security: + * deallocate security struct for this semaphore + * @sma contains the semaphore structure. + * @sem_associate: + * Check permission when a semaphore is requested through the semget + * system call. This hook is only called when returning the semaphore + * identifier for an existing semaphore, not when a new one must be + * created. + * @sma contains the semaphore structure. + * @semflg contains the operation control flags. + * Return 0 if permission is granted. + * @sem_semctl: + * Check permission when a semaphore operation specified by @cmd is to be + * performed on the semaphore @sma. The @sma may be NULL, e.g. for + * IPC_INFO or SEM_INFO. + * @sma contains the semaphore structure. May be NULL. + * @cmd contains the operation to be performed. + * Return 0 if permission is granted. + * @sem_semop + * Check permissions before performing operations on members of the + * semaphore set @sma. If the @alter flag is nonzero, the semaphore set + * may be modified. + * @sma contains the semaphore structure. + * @sops contains the operations to perform. + * @nsops contains the number of operations to perform. + * @alter contains the flag indicating whether changes are to be made. + * Return 0 if permission is granted. + * + * @binder_set_context_mgr + * Check whether @mgr is allowed to be the binder context manager. + * @mgr contains the task_struct for the task being registered. + * Return 0 if permission is granted. + * @binder_transaction + * Check whether @from is allowed to invoke a binder transaction call + * to @to. + * @from contains the task_struct for the sending task. + * @to contains the task_struct for the receiving task. + * @binder_transfer_binder + * Check whether @from is allowed to transfer a binder reference to @to. + * @from contains the task_struct for the sending task. + * @to contains the task_struct for the receiving task. + * @binder_transfer_file + * Check whether @from is allowed to transfer @file to @to. + * @from contains the task_struct for the sending task. + * @file contains the struct file being transferred. + * @to contains the task_struct for the receiving task. + * + * @ptrace_access_check: + * Check permission before allowing the current process to trace the + * @child process. + * Security modules may also want to perform a process tracing check + * during an execve in the set_security or apply_creds hooks of + * tracing check during an execve in the bprm_set_creds hook of + * binprm_security_ops if the process is being traced and its security + * attributes would be changed by the execve. + * @child contains the task_struct structure for the target process. + * @mode contains the PTRACE_MODE flags indicating the form of access. + * Return 0 if permission is granted. + * @ptrace_traceme: + * Check that the @parent process has sufficient permission to trace the + * current process before allowing the current process to present itself + * to the @parent process for tracing. + * @parent contains the task_struct structure for debugger process. + * Return 0 if permission is granted. + * @capget: + * Get the @effective, @inheritable, and @permitted capability sets for + * the @target process. The hook may also perform permission checking to + * determine if the current process is allowed to see the capability sets + * of the @target process. + * @target contains the task_struct structure for target process. + * @effective contains the effective capability set. + * @inheritable contains the inheritable capability set. + * @permitted contains the permitted capability set. + * Return 0 if the capability sets were successfully obtained. + * @capset: + * Set the @effective, @inheritable, and @permitted capability sets for + * the current process. + * @new contains the new credentials structure for target process. + * @old contains the current credentials structure for target process. + * @effective contains the effective capability set. + * @inheritable contains the inheritable capability set. + * @permitted contains the permitted capability set. + * Return 0 and update @new if permission is granted. + * @capable: + * Check whether the @tsk process has the @cap capability in the indicated + * credentials. + * @cred contains the credentials to use. + * @ns contains the user namespace we want the capability in + * @cap contains the capability . + * @audit: Whether to write an audit message or not + * Return 0 if the capability is granted for @tsk. + * @syslog: + * Check permission before accessing the kernel message ring or changing + * logging to the console. + * See the syslog(2) manual page for an explanation of the @type values. + * @type contains the type of action. + * @from_file indicates the context of action (if it came from /proc). + * Return 0 if permission is granted. + * @settime: + * Check permission to change the system time. + * struct timespec and timezone are defined in include/linux/time.h + * @ts contains new time + * @tz contains new timezone + * Return 0 if permission is granted. + * @vm_enough_memory: + * Check permissions for allocating a new virtual mapping. + * @mm contains the mm struct it is being added to. + * @pages contains the number of pages. + * Return 0 if permission is granted. + * + * @ismaclabel: + * Check if the extended attribute specified by @name + * represents a MAC label. Returns 1 if name is a MAC + * attribute otherwise returns 0. + * @name full extended attribute name to check against + * LSM as a MAC label. + * + * @secid_to_secctx: + * Convert secid to security context. If secdata is NULL the length of + * the result will be returned in seclen, but no secdata will be returned. + * This does mean that the length could change between calls to check the + * length and the next call which actually allocates and returns the + * secdata. + * @secid contains the security ID. + * @secdata contains the pointer that stores the converted security + * context. + * @seclen pointer which contains the length of the data + * @secctx_to_secid: + * Convert security context to secid. + * @secid contains the pointer to the generated security ID. + * @secdata contains the security context. + * + * @release_secctx: + * Release the security context. + * @secdata contains the security context. + * @seclen contains the length of the security context. + * + * Security hooks for Audit + * + * @audit_rule_init: + * Allocate and initialize an LSM audit rule structure. + * @field contains the required Audit action. + * Fields flags are defined in include/linux/audit.h + * @op contains the operator the rule uses. + * @rulestr contains the context where the rule will be applied to. + * @lsmrule contains a pointer to receive the result. + * Return 0 if @lsmrule has been successfully set, + * -EINVAL in case of an invalid rule. + * + * @audit_rule_known: + * Specifies whether given @rule contains any fields related to + * current LSM. + * @rule contains the audit rule of interest. + * Return 1 in case of relation found, 0 otherwise. + * + * @audit_rule_match: + * Determine if given @secid matches a rule previously approved + * by @audit_rule_known. + * @secid contains the security id in question. + * @field contains the field which relates to current LSM. + * @op contains the operator that will be used for matching. + * @rule points to the audit rule that will be checked against. + * @actx points to the audit context associated with the check. + * Return 1 if secid matches the rule, 0 if it does not, -ERRNO on failure. + * + * @audit_rule_free: + * Deallocate the LSM audit rule structure previously allocated by + * audit_rule_init. + * @rule contains the allocated rule + * + * @inode_notifysecctx: + * Notify the security module of what the security context of an inode + * should be. Initializes the incore security context managed by the + * security module for this inode. Example usage: NFS client invokes + * this hook to initialize the security context in its incore inode to the + * value provided by the server for the file when the server returned the + * file's attributes to the client. + * + * Must be called with inode->i_mutex locked. + * + * @inode we wish to set the security context of. + * @ctx contains the string which we wish to set in the inode. + * @ctxlen contains the length of @ctx. + * + * @inode_setsecctx: + * Change the security context of an inode. Updates the + * incore security context managed by the security module and invokes the + * fs code as needed (via __vfs_setxattr_noperm) to update any backing + * xattrs that represent the context. Example usage: NFS server invokes + * this hook to change the security context in its incore inode and on the + * backing filesystem to a value provided by the client on a SETATTR + * operation. + * + * Must be called with inode->i_mutex locked. + * + * @dentry contains the inode we wish to set the security context of. + * @ctx contains the string which we wish to set in the inode. + * @ctxlen contains the length of @ctx. + * + * @inode_getsecctx: + * On success, returns 0 and fills out @ctx and @ctxlen with the security + * context for the given @inode. + * + * @inode we wish to get the security context of. + * @ctx is a pointer in which to place the allocated security context. + * @ctxlen points to the place to put the length of @ctx. + * This is the main security structure. + */ + struct security_operations { char name[SECURITY_NAME_MAX + 1]; -- 2.20.1