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mac_set(3) [freebsd man page]

MAC_SET(3)						   BSD Library Functions Manual 						MAC_SET(3)

NAME
mac_set_file, mac_set_fd, mac_set_proc -- set the MAC label for a file or process LIBRARY
Standard C Library (libc, -lc) SYNOPSIS
#include <sys/mac.h> int mac_set_file(const char *path, mac_t label); int mac_set_link(const char *path, mac_t label); int mac_set_fd(int fd, mac_t label); int mac_set_proc(mac_t label); DESCRIPTION
The mac_set_file() and mac_set_fd() functions associate a MAC label specified by label to the file referenced to by path_p, or to the file descriptor fd, respectively. Note that when a file descriptor references a socket, label operations on the file descriptor act on the socket, not on the file that may have been used as a rendezvous when binding the socket. The mac_set_link() function is the same as mac_set_file(), except that it does not follow symlinks. The mac_set_proc() function associates the MAC label specified by label to the calling process. A process is allowed to set a label for a file only if it has MAC write access to the file, and its effective user ID is equal to the owner of the file, or has appropriate privileges. RETURN VALUES
The mac_set_fd(), mac_set_file(), mac_set_link(), and mac_set_proc() functions return the value 0 if successful; otherwise the value -1 is returned and the global variable errno is set to indicate the error. ERRORS
[EACCES] MAC write access to the file is denied. [EBADF] The fd argument is not a valid file descriptor. [EINVAL] The label argument is not a valid MAC label, or the object referenced by fd is not appropriate for label operations. [EOPNOTSUPP] Setting MAC labels is not supported by the file referenced by fd. [EPERM] The calling process had insufficient privilege to change the MAC label. [EROFS] File system for the object being modified is read only. [ENAMETOOLONG] The length of the pathname in path_p exceeds PATH_MAX, or a component of the pathname is longer than NAME_MAX. [ENOENT] The file referenced by path_p does not exist. [ENOTDIR] A component of the pathname referenced by path_p is not a directory. SEE ALSO
mac(3), mac_free(3), mac_get(3), mac_is_present(3), mac_prepare(3), mac_text(3), posix1e(3), mac(4), mac(9) HISTORY
Support for Mandatory Access Control was introduced in FreeBSD 5.0 as part of the TrustedBSD Project. BSD
January 14, 2003 BSD

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MAC_GET(3)						   BSD Library Functions Manual 						MAC_GET(3)

NAME
mac_get_file, mac_get_link, mac_get_fd, mac_get_peer, mac_get_pid, mac_get_proc -- get the label of a file, socket, socket peer or process LIBRARY
Standard C Library (libc, -lc) SYNOPSIS
#include <sys/mac.h> int mac_get_file(const char *path, mac_t label); int mac_get_link(const char *path, mac_t label); int mac_get_fd(int fd, mac_t label); int mac_get_peer(int fd, mac_t label); int mac_get_pid(pid_t pid, mac_t label); int mac_get_proc(mac_t label); DESCRIPTION
The mac_get_file() system call returns the label associated with a file specified by pathname. The mac_get_link() function is the same as mac_get_file(), except that it does not follow symlinks. The mac_get_fd() system call returns the label associated with an object referenced by the specified file descriptor. Note that in the case of a file system socket, the label returned will be the socket label, which may be different from the label of the on-disk node acting as a rendezvous for the socket. The mac_get_peer() system call returns the label associated with the remote endpoint of a socket; the exact semantics of this call will depend on the protocol domain, communications type, and endpoint; typically this label will be cached when a con- nection-oriented protocol instance is first set up, and is undefined for datagram protocols. The mac_get_pid() and mac_get_proc() system calls return the process label associated with an arbitrary process ID, or the current process. Label storage for use with these calls must first be allocated and prepared using the mac_prepare(3) functions. When an application is done using a label, the memory may be returned using mac_free(3). ERRORS
[EACCES] A component of path is not searchable, or MAC read access to the file is denied. [EINVAL] The requested label operation is not valid for the object referenced by fd. [ENAMETOOLONG] The pathname pointed to by path exceeds PATH_MAX, or a component of the pathname exceeds NAME_MAX. [ENOENT] A component of path does not exist. [ENOMEM] Insufficient memory is available to allocate a new MAC label structure. [ENOTDIR] A component of path is not a directory. SEE ALSO
mac(3), mac_free(3), mac_prepare(3), mac_set(3), mac_text(3), posix1e(3), mac(4), mac(9) STANDARDS
POSIX.1e is described in IEEE POSIX.1e draft 17. Discussion of the draft continues on the cross-platform POSIX.1e implementation mailing list. To join this list, see the FreeBSD POSIX.1e implementation page for more information. HISTORY
Support for Mandatory Access Control was introduced in FreeBSD 5.0 as part of the TrustedBSD Project. BSD
December 21, 2001 BSD

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