OpenSolaris_b135/lib/libbsm/common/audit_crontab.c
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2003 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/systeminfo.h>
#include <bsm/audit.h>
#include <bsm/libbsm.h>
#include <bsm/audit_uevents.h>
#include <bsm/audit_private.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <pwd.h>
#include <locale.h>
#include "generic.h"
#define AUDIT_GET_DIFFS_NO_CRONTAB 1
#define AUDIT_GET_DIFFS_CRONTAB 0
#define AUDIT_GET_DIFFS_ERR -1
#define AUDIT_GET_DIFFS_NO_DIFFS -2
static int audit_crontab_get_diffs(char *cf, char *tmp_name,
char **bufptr);
int
audit_crontab_modify(char *path, char *tmp_path, int sorf)
{
int r, create = 0;
char *diffs = NULL;
if (cannot_audit(0)) {
return (0);
} else {
au_event_t event;
char *anc_name;
auditinfo_addr_t ai;
if (getaudit_addr(&ai, sizeof (ai))) {
return (-1);
}
r = audit_crontab_get_diffs(path, tmp_path, &diffs);
if (r == AUDIT_GET_DIFFS_NO_DIFFS) {
return (0);
}
if (diffs != NULL && r != AUDIT_GET_DIFFS_ERR) {
aug_save_text(diffs);
free(diffs);
}
if (r == AUDIT_GET_DIFFS_NO_CRONTAB) {
create = 1;
if (diffs == NULL)
aug_save_text("");
}
/*
* create an ancilary file if audit characteristics exist
* else delete an ancilary if if one exists
*/
anc_name = audit_cron_make_anc_name(path);
if (anc_name == NULL)
r = -1;
else if (audit_crontab_process_not_audited()) {
(void) unlink(anc_name);
free(anc_name);
} else {
r = audit_cron_setinfo(anc_name, &ai);
free(anc_name);
}
aug_init();
aug_save_auid(ai.ai_auid);
aug_save_euid(geteuid());
aug_save_egid(getegid());
aug_save_uid(getuid());
aug_save_gid(getgid());
aug_save_pid(getpid());
aug_save_asid(ai.ai_asid);
aug_save_tid_ex(ai.ai_termid.at_port, ai.ai_termid.at_addr,
ai.ai_termid.at_type);
aug_save_path(path);
event = (create) ? AUE_crontab_create : AUE_crontab_mod;
aug_save_event(event);
aug_save_sorf(sorf);
if (aug_audit() != 0)
return (-1);
return (r);
}
}
int
audit_crontab_delete(char *path, int sorf)
{
int r = 0;
if (cannot_audit(0)) {
return (0);
} else {
char *anc_name;
anc_name = audit_cron_make_anc_name(path);
if (anc_name != NULL) {
r = unlink(anc_name);
free(anc_name);
} else
r = -1;
aug_init();
(void) aug_save_me();
aug_save_path(path);
aug_save_event(AUE_crontab_delete);
aug_save_sorf(sorf);
if (aug_audit() != 0)
return (-1);
return (r);
}
}
/*
* gets differences between old and new crontab files.
* arguments:
* cf - name of crontab file
* tmp_name - name of new crontab file
* bufptr - pointer to an array of characters with
* either an error message or an output of "diff" command.
*
* results:
* AUDIT_GET_DIFFS_ERR - errors;
* file not exists (do not free *bufptr in this case)
* AUDIT_GET_DIFFS_NO_DIFFS - errors;
* file exists (do not free *bufptr in this case)
* AUDIT_GET_DIFFS_CRONTAB - OK, old crontab file exists.
* AUDIT_GET_DIFFS_NO_CRONTAB - OK. there is no crontab file.
*/
static int
audit_crontab_get_diffs(char *cf, char *tmp_name, char **bufptr)
{
struct stat st, st_tmp;
uid_t euid;
int len, r = AUDIT_GET_DIFFS_CRONTAB;
char *buf = NULL, err_buf[128];
(void) memset(err_buf, 0, 128);
euid = geteuid();
if (seteuid(0) == -1) {
r = AUDIT_GET_DIFFS_ERR;
(void) snprintf(err_buf, sizeof (err_buf),
"crontab: seteuid: %s\n", strerror(errno));
goto exit_diff;
}
if (stat(cf, &st) == -1) {
if (errno == ENOENT) {
r = AUDIT_GET_DIFFS_NO_CRONTAB;
} else {
r = AUDIT_GET_DIFFS_ERR;
(void) snprintf(err_buf, sizeof (err_buf),
"crontab: %s: stat: %s\n",
cf, strerror(errno));
goto exit_diff;
}
len = 0;
} else
len = st.st_size;
if (stat(tmp_name, &st_tmp) == -1) {
r = AUDIT_GET_DIFFS_ERR;
(void) snprintf(err_buf, sizeof (err_buf),
"crontab: %s: stat: %s\n",
tmp_name, strerror(errno));
goto exit_diff;
}
if (st_tmp.st_size == 0 && len == 0) {
/* there is no difference */
r = AUDIT_GET_DIFFS_NO_DIFFS;
*bufptr = NULL;
goto exit_diff;
}
exit_diff:
/* return information on create or update crontab */
(void) seteuid(euid);
switch (r) {
case AUDIT_GET_DIFFS_ERR:
if (buf != NULL)
free(buf);
*bufptr = err_buf;
break;
case AUDIT_GET_DIFFS_NO_DIFFS:
if (buf != NULL)
free(buf);
*bufptr = NULL;
break;
case AUDIT_GET_DIFFS_CRONTAB:
if (buf != NULL) {
if (strlen(buf) != 0) {
*bufptr = buf;
} else {
r = AUDIT_GET_DIFFS_NO_DIFFS;
*bufptr = NULL;
}
}
break;
case AUDIT_GET_DIFFS_NO_CRONTAB:
if (buf != NULL) {
if (strlen(buf) != 0) {
*bufptr = buf;
} else {
*bufptr = NULL;
free(buf);
}
}
break;
}
return (r);
}
/*
* audit_crontab_not_allowed determines if we have a case that should be audited
* but we can't. If auditing is enabled but the current process is not
* audited, then the ruid of the user doing the editing must be the owner
* id of the file to be edited.
*
* When audit_crontab_not_allowed is called, ruid is for the crontab file
* to be modified or created.
*/
#define PWD_BUFFER_SIZE 512
int
audit_crontab_not_allowed(uid_t ruid, char *user) {
struct passwd pwd;
char buffer[PWD_BUFFER_SIZE];
int rc = 0; /* 0 == allow */
if (!cannot_audit(0)) { /* allow access if audit off */
if (getpwnam_r(user, &pwd, buffer, PWD_BUFFER_SIZE) == NULL) {
rc = 1; /* deny access if invalid */
} else if (ruid == pwd.pw_uid)
rc = 0; /* editing his own crontab */
else
rc = audit_crontab_process_not_audited();
}
return (rc);
}
int
audit_crontab_process_not_audited() {
struct auditpinfo_addr info;
int rc;
info.ap_pid = getpid();
if (auditon(A_GETPINFO_ADDR, (caddr_t)&info, sizeof (info)) != 0)
rc = 0; /* audit failure: not enabled */
else
rc = (info.ap_auid == AU_NOAUDITID);
return (rc);
}