summaryrefslogtreecommitdiffstats
path: root/libbsm/bsm_audit.c
diff options
context:
space:
mode:
authorrwatson <rwatson@FreeBSD.org>2008-11-12 23:48:20 +0000
committerrwatson <rwatson@FreeBSD.org>2008-11-12 23:48:20 +0000
commit2bd138f9edd4a43ef97291f03523af35e1ae18f8 (patch)
treee103f4f6bb4ebb161c9702d64560b216d1990d94 /libbsm/bsm_audit.c
parent280c17909566cfd4eff091c2747edb9d747f7343 (diff)
downloadFreeBSD-src-2bd138f9edd4a43ef97291f03523af35e1ae18f8.zip
FreeBSD-src-2bd138f9edd4a43ef97291f03523af35e1ae18f8.tar.gz
Flatten OpenBSM vendor tree in preparation for new OpenBSM vendor
import.
Diffstat (limited to 'libbsm/bsm_audit.c')
-rw-r--r--libbsm/bsm_audit.c383
1 files changed, 383 insertions, 0 deletions
diff --git a/libbsm/bsm_audit.c b/libbsm/bsm_audit.c
new file mode 100644
index 0000000..2f6df41
--- /dev/null
+++ b/libbsm/bsm_audit.c
@@ -0,0 +1,383 @@
+/*
+ * Copyright (c) 2004 Apple Computer, Inc.
+ * Copyright (c) 2005 SPARTA, Inc.
+ * All rights reserved.
+ *
+ * This code was developed in part by Robert N. M. Watson, Senior Principal
+ * Scientist, SPARTA, Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of
+ * its contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ * $P4: //depot/projects/trustedbsd/openbsm/libbsm/bsm_audit.c#28 $
+ */
+
+#include <sys/types.h>
+
+#include <config/config.h>
+#ifdef HAVE_FULL_QUEUE_H
+#include <sys/queue.h>
+#else
+#include <compat/queue.h>
+#endif
+
+#include <bsm/audit_internal.h>
+#include <bsm/libbsm.h>
+
+#include <errno.h>
+#include <pthread.h>
+#include <stdlib.h>
+#include <string.h>
+
+/* array of used descriptors */
+static au_record_t *open_desc_table[MAX_AUDIT_RECORDS];
+
+/* The current number of active record descriptors */
+static int audit_rec_count = 0;
+
+/*
+ * Records that can be recycled are maintained in the list given below. The
+ * maximum number of elements that can be present in this list is bounded by
+ * MAX_AUDIT_RECORDS. Memory allocated for these records are never freed.
+ */
+static LIST_HEAD(, au_record) audit_free_q;
+
+static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
+
+/*
+ * This call frees a token_t and its internal data.
+ */
+void
+au_free_token(token_t *tok)
+{
+
+ if (tok != NULL) {
+ if (tok->t_data)
+ free(tok->t_data);
+ free(tok);
+ }
+}
+
+/*
+ * This call reserves memory for the audit record. Memory must be guaranteed
+ * before any auditable event can be generated. The au_record_t structure
+ * maintains a reference to the memory allocated above and also the list of
+ * tokens associated with this record. Descriptors are recyled once the
+ * records are added to the audit trail following au_close().
+ */
+int
+au_open(void)
+{
+ au_record_t *rec = NULL;
+
+ pthread_mutex_lock(&mutex);
+
+ if (audit_rec_count == 0)
+ LIST_INIT(&audit_free_q);
+
+ /*
+ * Find an unused descriptor, remove it from the free list, mark as
+ * used.
+ */
+ if (!LIST_EMPTY(&audit_free_q)) {
+ rec = LIST_FIRST(&audit_free_q);
+ rec->used = 1;
+ LIST_REMOVE(rec, au_rec_q);
+ }
+
+ pthread_mutex_unlock(&mutex);
+
+ if (rec == NULL) {
+ /*
+ * Create a new au_record_t if no descriptors are available.
+ */
+ rec = malloc (sizeof(au_record_t));
+ if (rec == NULL)
+ return (-1);
+
+ rec->data = malloc (MAX_AUDIT_RECORD_SIZE * sizeof(u_char));
+ if (rec->data == NULL) {
+ free(rec);
+ errno = ENOMEM;
+ return (-1);
+ }
+
+ pthread_mutex_lock(&mutex);
+
+ if (audit_rec_count == MAX_AUDIT_RECORDS) {
+ pthread_mutex_unlock(&mutex);
+ free(rec->data);
+ free(rec);
+
+ /* XXX We need to increase size of MAX_AUDIT_RECORDS */
+ errno = ENOMEM;
+ return (-1);
+ }
+ rec->desc = audit_rec_count;
+ open_desc_table[audit_rec_count] = rec;
+ audit_rec_count++;
+
+ pthread_mutex_unlock(&mutex);
+
+ }
+
+ memset(rec->data, 0, MAX_AUDIT_RECORD_SIZE);
+
+ TAILQ_INIT(&rec->token_q);
+ rec->len = 0;
+ rec->used = 1;
+
+ return (rec->desc);
+}
+
+/*
+ * Store the token with the record descriptor.
+ *
+ * Don't permit writing more to the buffer than would let the trailer be
+ * appended later.
+ */
+int
+au_write(int d, token_t *tok)
+{
+ au_record_t *rec;
+
+ if (tok == NULL) {
+ errno = EINVAL;
+ return (-1); /* Invalid Token */
+ }
+
+ /* Write the token to the record descriptor */
+ rec = open_desc_table[d];
+ if ((rec == NULL) || (rec->used == 0)) {
+ errno = EINVAL;
+ return (-1); /* Invalid descriptor */
+ }
+
+ if (rec->len + tok->len + AUDIT_TRAILER_SIZE > MAX_AUDIT_RECORD_SIZE) {
+ errno = ENOMEM;
+ return (-1);
+ }
+
+ /* Add the token to the tail */
+ /*
+ * XXX Not locking here -- we should not be writing to
+ * XXX the same descriptor from different threads
+ */
+ TAILQ_INSERT_TAIL(&rec->token_q, tok, tokens);
+
+ rec->len += tok->len; /* grow record length by token size bytes */
+
+ /* Token should not be available after this call */
+ tok = NULL;
+ return (0); /* Success */
+}
+
+/*
+ * Assemble an audit record out of its tokens, including allocating header and
+ * trailer tokens. Does not free the token chain, which must be done by the
+ * caller if desirable.
+ *
+ * XXX: Assumes there is sufficient space for the header and trailer.
+ */
+static int
+au_assemble(au_record_t *rec, short event)
+{
+ token_t *header, *tok, *trailer;
+ size_t tot_rec_size;
+ u_char *dptr;
+ int error;
+
+ tot_rec_size = rec->len + AUDIT_HEADER_SIZE + AUDIT_TRAILER_SIZE;
+ header = au_to_header32(tot_rec_size, event, 0);
+ if (header == NULL)
+ return (-1);
+
+ trailer = au_to_trailer(tot_rec_size);
+ if (trailer == NULL) {
+ error = errno;
+ au_free_token(header);
+ errno = error;
+ return (-1);
+ }
+
+ TAILQ_INSERT_HEAD(&rec->token_q, header, tokens);
+ TAILQ_INSERT_TAIL(&rec->token_q, trailer, tokens);
+
+ rec->len = tot_rec_size;
+ dptr = rec->data;
+
+ TAILQ_FOREACH(tok, &rec->token_q, tokens) {
+ memcpy(dptr, tok->t_data, tok->len);
+ dptr += tok->len;
+ }
+
+ return (0);
+}
+
+/*
+ * Given a record that is no longer of interest, tear it down and convert to a
+ * free record.
+ */
+static void
+au_teardown(au_record_t *rec)
+{
+ token_t *tok;
+
+ /* Free the token list */
+ while ((tok = TAILQ_FIRST(&rec->token_q)) != NULL) {
+ TAILQ_REMOVE(&rec->token_q, tok, tokens);
+ free(tok->t_data);
+ free(tok);
+ }
+
+ rec->used = 0;
+ rec->len = 0;
+
+ pthread_mutex_lock(&mutex);
+
+ /* Add the record to the freelist tail */
+ LIST_INSERT_HEAD(&audit_free_q, rec, au_rec_q);
+
+ pthread_mutex_unlock(&mutex);
+}
+
+#ifdef HAVE_AUDIT_SYSCALLS
+/*
+ * Add the header token, identify any missing tokens. Write out the tokens to
+ * the record memory and finally, call audit.
+ */
+int
+au_close(int d, int keep, short event)
+{
+ au_record_t *rec;
+ size_t tot_rec_size;
+ int retval = 0;
+
+ rec = open_desc_table[d];
+ if ((rec == NULL) || (rec->used == 0)) {
+ errno = EINVAL;
+ return (-1); /* Invalid descriptor */
+ }
+
+ if (keep == AU_TO_NO_WRITE) {
+ retval = 0;
+ goto cleanup;
+ }
+
+ tot_rec_size = rec->len + AUDIT_HEADER_SIZE + AUDIT_TRAILER_SIZE;
+
+ if (tot_rec_size > MAX_AUDIT_RECORD_SIZE) {
+ /*
+ * XXXRW: Since au_write() is supposed to prevent this, spew
+ * an error here.
+ */
+ fprintf(stderr, "au_close failed");
+ errno = ENOMEM;
+ retval = -1;
+ goto cleanup;
+ }
+
+ if (au_assemble(rec, event) < 0) {
+ /*
+ * XXXRW: This is also not supposed to happen, but might if we
+ * are unable to allocate header and trailer memory.
+ */
+ retval = -1;
+ goto cleanup;
+ }
+
+ /* Call the kernel interface to audit */
+ retval = audit(rec->data, rec->len);
+
+cleanup:
+ /* CLEANUP */
+ au_teardown(rec);
+ return (retval);
+}
+#endif /* HAVE_AUDIT_SYSCALLS */
+
+/*
+ * au_close(), except onto an in-memory buffer. Buffer size as an argument,
+ * record size returned via same argument on success.
+ */
+int
+au_close_buffer(int d, short event, u_char *buffer, size_t *buflen)
+{
+ size_t tot_rec_size;
+ au_record_t *rec;
+ int retval;
+
+ rec = open_desc_table[d];
+ if ((rec == NULL) || (rec->used == 0)) {
+ errno = EINVAL;
+ return (-1);
+ }
+
+ retval = 0;
+ tot_rec_size = rec->len + AUDIT_HEADER_SIZE + AUDIT_TRAILER_SIZE;
+ if ((tot_rec_size > MAX_AUDIT_RECORD_SIZE) ||
+ (tot_rec_size > *buflen)) {
+ /*
+ * XXXRW: See au_close() comment.
+ */
+ fprintf(stderr, "au_close_buffer failed %zd", tot_rec_size);
+ errno = ENOMEM;
+ retval = -1;
+ goto cleanup;
+ }
+
+ if (au_assemble(rec, event) < 0) {
+ /* XXXRW: See au_close() comment. */
+ retval = -1;
+ goto cleanup;
+ }
+
+ memcpy(buffer, rec->data, rec->len);
+ *buflen = rec->len;
+
+cleanup:
+ au_teardown(rec);
+ return (retval);
+}
+
+/*
+ * au_close_token() returns the byte format of a token_t. This won't
+ * generally be used by applications, but is quite useful for writing test
+ * tools. Will free the token on either success or failure.
+ */
+int
+au_close_token(token_t *tok, u_char *buffer, size_t *buflen)
+{
+
+ if (tok->len > *buflen) {
+ au_free_token(tok);
+ errno = ENOMEM;
+ return (EINVAL);
+ }
+
+ memcpy(buffer, tok->t_data, tok->len);
+ *buflen = tok->len;
+ au_free_token(tok);
+ return (0);
+}
OpenPOWER on IntegriCloud