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/*
* Linux Security Module interfaces
*
* Copyright (C) 2001 WireX Communications, Inc <[email protected]>
* Copyright (C) 2001 Greg Kroah-Hartman <[email protected]>
* Copyright (C) 2001 Networks Associates Technology, Inc <[email protected]>
* Copyright (C) 2001 James Morris <[email protected]>
* Copyright (C) 2001 Silicon Graphics, Inc. (Trust Technology Group)
* Copyright (C) 2015 Intel Corporation.
* Copyright (C) 2015 Casey Schaufler <[email protected]>
* Copyright (C) 2016 Mellanox Techonologies
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* Due to this file being licensed under the GPL there is controversy over
* whether this permits you to write a module that #includes this file
* without placing your module under the GPL. Please consult a lawyer for
* advice before doing this.
*
*/
#ifndef __LINUX_LSM_HOOKS_H
#define __LINUX_LSM_HOOKS_H
#include <linux/security.h>
#include <linux/init.h>
#include <linux/rculist.h>
/**
* union security_list_options - Linux Security Module hook function list
*
* 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_creds_from_file:
* If @file is setpcap, suid, sgid or otherwise marked to change
* privilege upon exec, update @bprm->cred to reflect that change.
* This is called after finding the binary that will be executed.
* without an interpreter. This ensures that the credentials will not
* be derived from a script that the binary will need to reopen, which
* when reopend may end up being a completely different file. 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.
* The hook must add to @bprm->per_clear any personality flags that
* should be cleared from current->personality.
* @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 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_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
* 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().
*
* Security hooks for mount using fs_context.
* [See also Documentation/filesystems/mount_api.rst]
*
* @fs_context_dup:
* Allocate and attach a security structure to sc->security. This pointer
* is initialised to NULL by the caller.
* @fc indicates the new filesystem context.
* @src_fc indicates the original filesystem context.
* @fs_context_parse_param:
* Userspace provided a parameter to configure a superblock. The LSM may
* reject it with an error and may use it for itself, in which case it
* should return 0; otherwise it should return -ENOPARAM to pass it on to
* the filesystem.
* @fc indicates the filesystem context.
* @param The parameter
*
* 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_delete:
* Release objects tied to a superblock (e.g. inodes).
* @sb contains the super_block structure being released.
* @sb_free_security:
* Deallocate and clear the sb->s_security field.
* @sb contains the super_block structure to be modified.
* @sb_free_mnt_opts:
* Free memory associated with @mnt_ops.
* @sb_eat_lsm_opts:
* Eat (scan @orig options) and save them in @mnt_opts.
* @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.
* @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_mnt_opts_compat:
* Determine if the new mount options in @mnt_opts are allowed given
* the existing mounted filesystem at @sb.
* @sb superblock being compared
* @mnt_opts new mount options
* Return 0 if options are compatible.
* @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_kern_mount:
* Mount this @sb if allowed by permissions.
* @sb_show_options:
* Show (print on @m) mount options for this @sb.
* @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_add_mnt_opt:
* Add one mount @option to @mnt_opts.
* @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
* @move_mount:
* Check permission before a mount is moved.
* @from_path indicates the mount that is going to be moved.
* @to_path indicates the mountpoint that will be mounted upon.
* @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.
* @dentry_create_files_as:
* Compute a context for a dentry as the inode is not yet available
* and set that context in passed in creds so that new files are
* created using that context. Context is calculated using the
* passed in creds and not the creds of the caller.
* @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
* @old creds which should be used for context calculation
* @new creds to modify
*
*
* 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_init_security_anon:
* Set up the incore security field for the new anonymous inode
* and return whether the inode creation is permitted by the security
* module or not.
* @inode contains the inode structure
* @name name of the anonymous inode class
* @context_inode optional related inode
* Returns 0 on success, -EACCES if the security module denies the
* creation of this inode, or another -errno upon other errors.
* @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 a mode of the file @path. The new
* mode is specified in @mode.
* @path contains the path structure of the file to change the mode.
* @mode contains the new DAC's permission, which is a bitmask of
* constants from <include/uapi/linux/stat.h>
* 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.
* @path_notify:
* Check permissions before setting a watch on events as defined by @mask,
* on an object at @path, whose type is defined by @obj_type.
* @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.
* @inode contains the inode, which itself is not stable in RCU-walk
* @rcu indicates whether we are in RCU-walk mode.
* 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.
* @path contains the path 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.
* @mnt_userns: user namespace of the mount
* @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.
* @inode_copy_up:
* A file is about to be copied up from lower layer to upper layer of
* overlay filesystem. Security module can prepare a set of new creds
* and modify as need be and return new creds. Caller will switch to
* new creds temporarily to create new file and release newly allocated
* creds.
* @src indicates the union dentry of file that is being copied up.
* @new pointer to pointer to return newly allocated creds.
* Returns 0 on success or a negative error code on error.
* @inode_copy_up_xattr:
* Filter the xattrs being copied up when a unioned file is copied
* up from a lower layer to the union/overlay layer.
* @name indicates the name of the xattr.
* Returns 0 to accept the xattr, 1 to discard the xattr, -EOPNOTSUPP if
* security module does not know about attribute or a negative error code
* to abort the copy up. Note that the caller is responsible for reading
* and writing the xattrs as this hook is merely a filter.
* @d_instantiate:
* Fill in @inode security information for a @dentry if allowed.
* @getprocattr:
* Read attribute @name for process @p and store it into @value if allowed.
* @setprocattr:
* Write (set) attribute @name to @value, size @size if allowed.
*
* Security hooks for kernfs node operations
*
* @kernfs_init_security:
* Initialize the security context of a newly created kernfs node based
* on its own and its parent's attributes.
*
* @kn_dir the parent kernfs node
* @kn the new child kernfs node
*
* 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 the 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_alloc:
* @task task being allocated.
* @clone_flags contains the flags indicating what should be shared.
* Handle allocation of task-related resources.
* Returns a zero on success, negative values on failure.
* @task_free:
* @task task about to be 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
* @cred_getsecid:
* Retrieve the security identifier of the cred structure @c
* @c contains the credentials, secid will be placed into @secid.
* In case of failure, @secid will be set to zero.
* @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_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_load_data:
* Load data provided by userspace.
* @id kernel load data identifier
* @contents if a subsequent @kernel_post_load_data will be called.
* Return 0 if permission is granted.
* @kernel_post_load_data:
* Load data provided by a non-file source (usually userspace buffer).
* @buf pointer to buffer containing the data contents.
* @size length of the data contents.
* @id kernel load data identifier
* @description a text description of what was loaded, @id-specific
* Return 0 if permission is granted.
* This must be paired with a prior @kernel_load_data call that had
* @contents set to true.
* @kernel_read_file:
* Read a file specified by userspace.
* @file contains the file structure pointing to the file being read
* by the kernel.
* @id kernel read file identifier
* @contents if a subsequent @kernel_post_read_file will be called.
* Return 0 if permission is granted.
* @kernel_post_read_file:
* Read a file specified by userspace.
* @file contains the file structure pointing to the file being read
* by the kernel.
* @buf pointer to buffer containing the file contents.
* @size length of the file contents.
* @id kernel read file identifier
* This must be paired with a prior @kernel_read_file call that had
* @contents set to true.
* 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_fix_setgid:
* Update the module's state after setting one or more of the group
* identity attributes of the current process. The @flags parameter
* indicates which of the set*gid system calls invoked this hook.
* @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 replaced.
* @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_subj:
* Retrieve the subjective security identifier of the task_struct in @p
* and return it in @secid. Special care must be taken to ensure that @p
* is the either the "current" task, or the caller has exclusive access
* to @p.
* In case of failure, @secid will be set to zero.
* @task_getsecid_obj:
* Retrieve the objective security identifier of the task_struct in @p
* and return it in @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_prlimit:
* Check permission before getting and/or setting the resource limits of
* another task.
* @cred points to the cred structure for the current task.
* @tcred points to the cred structure for the target task.
* @flags contains the LSM_PRLIMIT_* flag bits indicating whether the
* resource limits are being read, modified, or both.
* Return 0 if permission is granted.
* @task_setrlimit:
* Check permission before setting the resource limits of process @p
* for @resource to @new_rlim. The old resource limit values can
* be examined by dereferencing (p->signal->rlim + resource).
* @p points to the task_struct for the target task's group leader.
* @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.
* @p contains the task_struct for process.
* 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 kernel_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.
* @cred contains the cred of the process where the signal originated, or
* NULL if the current task is the originator.
* 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 attach security information to
* SOCK_INODE(sock)->i_security. This hook may be used to update the
* SOCK_INODE(sock)->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_socketpair:
* Check permissions before creating a fresh pair of sockets.
* @socka contains the first socket structure.
* @sockb contains the second socket structure.
* Return 0 if permission is granted and the connection was established.
* @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.
* @sock contains the peer socket. May be NULL.
* @skb is the sk_buff for the packet being queried. May be NULL.
* @secid pointer to store the secid of the packet.
* 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
* @secmark_refcount_inc:
* tells the LSM to increment the number of secmark labeling rules loaded
* @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 SCTP
*
* @sctp_assoc_request:
* Passes the @ep and @chunk->skb of the association INIT packet to
* the security module.
* @ep pointer to sctp endpoint structure.
* @skb pointer to skbuff of association packet.
* Return 0 on success, error on failure.
* @sctp_bind_connect:
* Validiate permissions required for each address associated with sock
* @sk. Depending on @optname, the addresses will be treated as either
* for a connect or bind service. The @addrlen is calculated on each
* ipv4 and ipv6 address using sizeof(struct sockaddr_in) or
* sizeof(struct sockaddr_in6).
* @sk pointer to sock structure.
* @optname name of the option to validate.
* @address list containing one or more ipv4/ipv6 addresses.
* @addrlen total length of address(s).
* Return 0 on success, error on failure.
* @sctp_sk_clone:
* Called whenever a new socket is created by accept(2) (i.e. a TCP
* style socket) or when a socket is 'peeled off' e.g userspace
* calls sctp_peeloff(3).
* @ep pointer to current sctp endpoint structure.
* @sk pointer to current sock structure.
* @sk pointer to new sock structure.
*
* Security hooks for Infiniband
*
* @ib_pkey_access:
* Check permission to access a pkey when modifing a QP.
* @subnet_prefix the subnet prefix of the port being used.
* @pkey the pkey to be accessed.
* @sec pointer to a security structure.
* @ib_endport_manage_subnet:
* Check permissions to send and receive SMPs on a end port.
* @dev_name the IB device name (i.e. mlx4_0).
* @port_num the port number.
* @sec pointer to a security structure.
* @ib_alloc_security:
* Allocate a security structure for Infiniband objects.
* @sec pointer to a security structure pointer.
* Returns 0 on success, non-zero on failure
* @ib_free_security:
* Deallocate an Infiniband security structure.
* @sec contains the security structure to be freed.
*
* 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.
* @flic contains the flowi_common struct 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
* @perm->security field. The security field is initialized to
* NULL when the structure is first created.
* @perm contains the IPC permissions of the message queue.
* Return 0 if operation was successful and permission is granted.
* @msg_queue_free_security:
* Deallocate security field @perm->security for the message queue.
* @perm contains the IPC permissions of the message queue.
* @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.
* @perm contains the IPC permissions of the message queue.
* @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 with permissions @perm.
* The @perm may be NULL, e.g. for IPC_INFO or MSG_INFO.
* @perm contains the IPC permissions of the msg queue. 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 with permissions @perm.
* @perm contains the IPC permissions of the message queue.
* @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. 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).
* @perm contains the IPC permissions of the message queue.
* @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 @perm->security
* field. The security field is initialized to NULL when the structure is
* first created.
* @perm contains the IPC permissions of the shared memory structure.
* Return 0 if operation was successful and permission is granted.
* @shm_free_security:
* Deallocate the security structure @perm->security for the memory segment.
* @perm contains the IPC permissions of the shared memory structure.
* @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.
* @perm contains the IPC permissions of the shared memory structure.
* @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 with permissions @perm.
* The @perm may be NULL, e.g. for IPC_INFO or SHM_INFO.
* @perm contains the IPC permissions of the shared memory structure.
* @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 with permissions @perm to the data segment of the
* calling process. The attaching address is specified by @shmaddr.
* @perm contains the IPC permissions of the shared memory structure.
* @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 @perm->security
* field. The security field is initialized to NULL when the structure is
* first created.
* @perm contains the IPC permissions of the semaphore.
* Return 0 if operation was successful and permission is granted.
* @sem_free_security:
* Deallocate security structure @perm->security for the semaphore.
* @perm contains the IPC permissions of the semaphore.
* @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.
* @perm contains the IPC permissions of the semaphore.
* @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. The @perm may be NULL, e.g. for
* IPC_INFO or SEM_INFO.
* @perm contains the IPC permissions of the semaphore. 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. If the @alter flag is nonzero, the semaphore set
* may be modified.
* @perm contains the IPC permissions of the semaphore.
* @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 <include/linux/capability.h>.
* @opts contains options for the capable check <include/linux/security.h>
* Return 0 if the capability is granted for @tsk.
* @quotactl:
* Check whether the quotactl syscall is allowed for this @sb.
* @quota_on:
* Check whether QUOTAON is allowed for this @dentry.
* @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 SYSLOG_ACTION_* constant from <include/linux/syslog.h>
* Return 0 if permission is granted.
* @settime:
* Check permission to change the system time.
* struct timespec64 is defined in <include/linux/time64.h> and timezone
* is 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.
*
* @getprocattr:
* Provide the named process attribute for display in special files in
* the /proc/.../attr directory. Attribute naming and the data displayed
* is at the discretion of the security modules. The exception is the
* "context" attribute, which will contain the security context of the
* task as a nul terminated text string without trailing whitespace.
* @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 @krule contains any fields related to
* current LSM.
* @krule 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.
* @lrule points to the audit rule that will be checked against.
* 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.
* @lsmrule contains the allocated rule
*
* @inode_invalidate_secctx:
* Notify the security module that it must revalidate the security context
* of an inode.
*
* @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.
*
* Security hooks for the general notification queue:
*
* @post_notification:
* Check to see if a watch notification can be posted to a particular
* queue.
* @w_cred: The credentials of the whoever set the watch.
* @cred: The event-triggerer's credentials
* @n: The notification being posted
*
* @watch_key:
* Check to see if a process is allowed to watch for event notifications
* from a key or keyring.
* @key: The key to watch.
*
* Security hooks for using the eBPF maps and programs functionalities through
* eBPF syscalls.
*
* @bpf:
* Do a initial check for all bpf syscalls after the attribute is copied
* into the kernel. The actual security module can implement their own
* rules to check the specific cmd they need.
*
* @bpf_map:
* Do a check when the kernel generate and return a file descriptor for
* eBPF maps.
*
* @map: bpf map that we want to access
* @mask: the access flags
*
* @bpf_prog:
* Do a check when the kernel generate and return a file descriptor for
* eBPF programs.
*
* @prog: bpf prog that userspace want to use.
*
* @bpf_map_alloc_security:
* Initialize the security field inside bpf map.
*
* @bpf_map_free_security:
* Clean up the security information stored inside bpf map.
*
* @bpf_prog_alloc_security:
* Initialize the security field inside bpf program.
*
* @bpf_prog_free_security:
* Clean up the security information stored inside bpf prog.
*
* @locked_down:
* Determine whether a kernel feature that potentially enables arbitrary
* code execution in kernel space should be permitted.
*
* @what: kernel feature being accessed
*
* @lock_kernel_down
* Put the kernel into lock-down mode.
*
* @where: Where the lock-down is originating from (e.g. command line option)
* @level: The lock-down level (can only increase)
*
* Security hooks for perf events
*
* @perf_event_open:
* Check whether the @type of perf_event_open syscall is allowed.
* @perf_event_alloc:
* Allocate and save perf_event security info.
* @perf_event_free:
* Release (free) perf_event security info.
* @perf_event_read:
* Read perf_event security info if allowed.
* @perf_event_write:
* Write perf_event security info if allowed.
*/
union security_list_options {
#define LSM_HOOK(RET, DEFAULT, NAME, ...) RET (*NAME)(__VA_ARGS__);
#include "lsm_hook_defs.h"
#undef LSM_HOOK
};
struct security_hook_heads {
#define LSM_HOOK(RET, DEFAULT, NAME, ...) struct hlist_head NAME;
#include "lsm_hook_defs.h"
#undef LSM_HOOK
} __randomize_layout;
/*
* Information that identifies a security module.
*/
struct lsm_id {
const char *lsm; /* Name of the LSM */
int slot; /* Slot in lsmblob if one is allocated */
};
/*
* Security module hook list structure.
* For use with generic list macros for common operations.
*/
struct security_hook_list {
struct hlist_node list;
struct hlist_head *head;
union security_list_options hook;
struct lsm_id *lsmid;
} __randomize_layout;
/*
* Security blob size or offset data.
*/
struct lsm_blob_sizes {
int lbs_cred;
int lbs_file;
int lbs_inode;
int lbs_superblock;
int lbs_sock;
int lbs_ipc;
int lbs_msg_msg;
int lbs_task;
};
/*
* LSM_RET_VOID is used as the default value in LSM_HOOK definitions for void
* LSM hooks (in include/linux/lsm_hook_defs.h).
*/
#define LSM_RET_VOID ((void) 0)
/*
* Initializing a security_hook_list structure takes
* up a lot of space in a source file. This macro takes
* care of the common case and reduces the amount of
* text involved.
*/
#define LSM_HOOK_INIT(HEAD, HOOK) \
{ .head = &security_hook_heads.HEAD, .hook = { .HEAD = HOOK } }
extern struct security_hook_heads security_hook_heads;
extern char *lsm_names;
extern void security_add_hooks(struct security_hook_list *hooks, int count,
struct lsm_id *lsmid);
#define LSM_FLAG_LEGACY_MAJOR BIT(0)
#define LSM_FLAG_EXCLUSIVE BIT(1)
enum lsm_order {
LSM_ORDER_FIRST = -1, /* This is only for capabilities. */
LSM_ORDER_MUTABLE = 0,
};
struct lsm_info {
const char *name; /* Required. */
enum lsm_order order; /* Optional: default is LSM_ORDER_MUTABLE */
unsigned long flags; /* Optional: flags describing LSM */
int *enabled; /* Optional: controlled by CONFIG_LSM */
int (*init)(void); /* Required. */
struct lsm_blob_sizes *blobs; /* Optional: for blob sharing. */
};
extern struct lsm_info __start_lsm_info[], __end_lsm_info[];
extern struct lsm_info __start_early_lsm_info[], __end_early_lsm_info[];
#define DEFINE_LSM(lsm) \
static struct lsm_info __lsm_##lsm \
__used __section(".lsm_info.init") \
__aligned(sizeof(unsigned long))
#define DEFINE_EARLY_LSM(lsm) \
static struct lsm_info __early_lsm_##lsm \
__used __section(".early_lsm_info.init") \
__aligned(sizeof(unsigned long))
#ifdef CONFIG_SECURITY_SELINUX_DISABLE
/*
* Assuring the safety of deleting a security module is up to
* the security module involved. This may entail ordering the
* module's hook list in a particular way, refusing to disable
* the module once a policy is loaded or any number of other
* actions better imagined than described.
*
* The name of the configuration option reflects the only module
* that currently uses the mechanism. Any developer who thinks
* disabling their module is a good idea needs to be at least as
* careful as the SELinux team.
*/
static inline void security_delete_hooks(struct security_hook_list *hooks,
int count)
{
int i;
for (i = 0; i < count; i++)
hlist_del_rcu(&hooks[i].list);
}
#endif /* CONFIG_SECURITY_SELINUX_DISABLE */
/* Currently required to handle SELinux runtime hook disable. */
#ifdef CONFIG_SECURITY_WRITABLE_HOOKS
#define __lsm_ro_after_init
#else
#define __lsm_ro_after_init __ro_after_init
#endif /* CONFIG_SECURITY_WRITABLE_HOOKS */
extern int lsm_inode_alloc(struct inode *inode);
/**
* lsm_task_display - the "display" LSM for this task
* @task: The task to report on
*
* Returns the task's display LSM slot.
*/
static inline int lsm_task_display(struct task_struct *task)
{
#ifdef CONFIG_SECURITY
int *display = task->security;
if (display)
return *display;
#endif
return LSMBLOB_INVALID;
}
#endif /* ! __LINUX_LSM_HOOKS_H */
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