AU_OPEN(3)             FreeBSD Library Functions Manual             AU_OPEN(3)

NAME

     au_close, au_close_buffer, au_close_token, au_open, au_write - create and
     commit audit records

LIBRARY

     Basic Security Module Library (libbsm, -lbsm)

SYNOPSIS

     #include <bsm/libbsm.h>

     int
     au_open(void);

     int
     au_write(int d, token_t *tok);

     int
     au_close(int d, int keep, short event);

     int
     au_close_buffer(int d, short event, u_char *buffer, size_t *buflen);

     int
     au_close_token(token_t *tok, u_char *buffer, size_t *buflen);

DESCRIPTION

     These interfaces allow applications to allocate audit records, construct
     a record using a series of tokens, and commit the audit record to the
     system event log.  An extension API is also provided to commit the record
     to an in-memory buffer rather than the system audit log.

     The au_open() interface allocates a new audit record descriptor.

     The au_write() interface adds a token to an allocated audit descriptor.
     When a token has been successfully added to a record, the caller no
     longer owns the token memory, and does not need to free it directly via a
     call to au_free_token(3).

     The au_close() function is used to commit an audit record to the system
     audit log, or abandon the record.  In either cases, all resources
     associated with the record will be released.  The keep argument
     determines the behavior: a value of AU_TO_WRITE causes the record to be
     committed; a value of AU_TO_NO_WRITE causes it to be abandoned.  When the
     audit record is committed, a BSM header will be inserted before tokens
     added to the record, using the event identifier passed via event, and a
     trailer added to the end.  Committing a record to the system audit log
     requires privilege.

     The au_close_buffer() function writes the resulting record to an in-
     memory buffer of size *buflen; it will write back the filled buffer
     length into the same variable.  The argument event is the event
     identifier to use in the record header.

     The au_close_token() function generates the BSM stream output for a
     single token, tok, in the passed buffer buffer.  The initial buffer size
     and resulting data size are passed via *buflen.  The au_close_token()
     function will free the token before returning.

RETURN VALUES

     The function au_open() returns a non-negative audit record descriptor
     number on success, or a negative value on failure, along with error
     information in errno.

     The functions au_write(), au_close(), au_close_buffer(), and
     au_close_token() return 0 on success, or a negative value on failure,
     along with error information in errno.

SEE ALSO

     audit_submit(3), libbsm(3)

HISTORY

     The OpenBSM implementation was created by McAfee Research, the security
     division of McAfee Inc., under contract to Apple Computer, Inc., in 2004.
     It was subsequently adopted by the TrustedBSD Project as the foundation
     for the OpenBSM distribution.

AUTHORS

     This software was created by Robert Watson, Wayne Salamon, and Suresh
     Krishnaswamy for McAfee Research, the security research division of
     McAfee, Inc., under contract to Apple Computer, Inc.

     The Basic Security Module (BSM) interface to audit records and audit
     event stream format were defined by Sun Microsystems.

BUGS

     Currently, au_open() does not reserve kernel resources necessary to
     commit the record to the trail; on systems supporting au_close(), the
     call will block until resources are available to commit the record.
     However, this leads to the possibility of an action being permitted
     without the record being guaranteed to go to disk.  Ideally, au_open()
     would reserve resources necessary to commit any submitted record,
     releasing them on au_close().

FreeBSD 15.1-STABLE-HBSD         March 4, 2006                      AU_OPEN(3)