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audisp-json.c
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audisp-json.c
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/* vim: ts=4:sw=4:noexpandtab
* audisp-json.c --
* Copyright (c) 2014 Mozilla Corporation.
* Portions Copyright 2008 Red Hat Inc., Durham, North Carolina.
* All Rights Reserved.
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Authors:
* Guillaume Destuynder <[email protected]>
* Steve Grubb <[email protected]>
*
*/
#include <stdio.h>
#include <signal.h>
#include <syslog.h>
#include <string.h>
#include <unistd.h>
#include <stdlib.h>
#include <errno.h>
#include <fcntl.h>
#include <pwd.h>
#include <netdb.h>
#include <sys/stat.h>
#include <time.h>
#include <curl/curl.h>
#include "libaudit.h"
#include "auparse.h"
#include "json-config.h"
#define CONFIG_FILE "/etc/audisp/audisp-json.conf"
#define CONFIG_FILE_LOCAL "audisp-json.conf"
/* after this amount of time for any response (connect, http reply, etc.) just give up
* and lose messages.
* don't set this too high as new curl handles will be created and consume memory while
* waiting for the connection to work again.
*/
#define MAX_CURL_GLOBAL_TIMEOUT 5000L
#define MAX_CURL_QUEUE_SIZE 8192
#define MAX_JSON_MSG_SIZE 4096
#define MAX_ARG_LEN 2048
#define MAX_SUMMARY_LEN 256
#define TS_LEN 64
#define MAX_ATTR_SIZE MAX_AUDIT_MESSAGE_LENGTH
#ifdef REORDER_HACK
#define NR_LINES_BUFFERED 64
#endif
#define HTTP_CODE_OK 200
#ifndef PROGRAM_VERSION
#define PROGRAM_VERSION "1"
#endif
#ifndef PROGRAM_NAME
#define PROGRAM_NAME "audisp-json"
#endif
/* transform macro int and str value to ... str - needed for defining USER_AGENT ;)*/
#define _STR(x) #x
#define STR(x) _STR(x)
#define USER_AGENT PROGRAM_NAME"/"STR(PROGRAM_VERSION)
extern int h_errno;
static volatile int sig_stop = 0;
static volatile int sig_hup = 0;
static json_conf_t config;
static char *hostname = NULL;
static auparse_state_t *au = NULL;
static int machine = -1;
static long int curl_timeout = -1;
FILE *curl_logfile;
CURLM *multi_h;
CURL *easy_h;
struct curl_slist *slist1;
int curl_nr_h = -1;
int msg_lost = 0;
typedef struct { char *val; } msg_t;
/* msg attributes list */
typedef struct ll {
char value[MAX_ATTR_SIZE];
struct ll *next;
} attr_t;
struct json_msg_type {
char *category;
char *summary;
char *severity;
char *hostname;
int processid;
char *processname;
char *timestamp;
struct ll *details;
};
/* msgs to send queue/buffer */
typedef struct lq {
char msg[MAX_JSON_MSG_SIZE];
struct lq *next;
} queue_t;
struct lq *msg_queue_list;
unsigned int msg_queue_list_size = 0;
void prepare_curl_handle(char *new_msg)
{
curl_easy_reset(easy_h);
curl_easy_setopt(easy_h, CURLOPT_URL, config.mozdef_url);
curl_easy_setopt(easy_h, CURLOPT_NOPROGRESS, 1L);
curl_easy_setopt(easy_h, CURLOPT_USERAGENT, USER_AGENT);
curl_easy_setopt(easy_h, CURLOPT_HTTPHEADER, slist1);
curl_easy_setopt(easy_h, CURLOPT_MAXREDIRS, 10L);
curl_easy_setopt(easy_h, CURLOPT_CUSTOMREQUEST, "POST");
/* keep alive is on by default and only settable in recent libcurl
* keeping this around in case its not actually default in some cases and needs
* to be conditionally enabled
*/
// curl_easy_setopt(easy_h, CURLOPT_TCP_KEEPALIVE, 1L);
/* if logfile is set, log there instead of stderr.
* this is generally useful in combination with the below curl_verbose option,
* since grabbing stderr from a running plugin may be difficult.
*/
if (config.curl_logfile != NULL) {
curl_logfile = fopen(config.curl_logfile, "ab");
curl_easy_setopt(easy_h, CURLOPT_STDERR, curl_logfile);
}
curl_easy_setopt(easy_h, CURLOPT_VERBOSE, config.curl_verbose);
curl_easy_setopt(easy_h, CURLOPT_TIMEOUT_MS, MAX_CURL_GLOBAL_TIMEOUT);
curl_easy_setopt(easy_h, CURLOPT_SSL_VERIFYHOST, config.ssl_verify);
curl_easy_setopt(easy_h, CURLOPT_SSL_VERIFYPEER, config.ssl_verify);
curl_easy_setopt(easy_h, CURLOPT_CAINFO, config.curl_cainfo);
curl_easy_setopt(easy_h, CURLOPT_COPYPOSTFIELDS, new_msg);
}
/* Insert/remove new messages in the queue
*/
int list_check_queue()
{
queue_t *prev;
if (!msg_queue_list) {
return 1;
}
prev = msg_queue_list;
msg_queue_list = msg_queue_list->next;
curl_multi_remove_handle(multi_h, easy_h);
if (prev) {
prepare_curl_handle(prev->msg);
free(prev);
msg_queue_list_size--;
curl_multi_add_handle(multi_h, easy_h);
}
return 0;
}
/* select and fetch urls */
void curl_perform(void)
{
int msgs_left;
int maxfd = -1;
long http_code = 0;
struct timeval timeout;
int rc;
CURLMsg *msg;
CURLcode ret;
fd_set r, w, e;
/* Cleanup completed handles */
while ((msg = curl_multi_info_read(multi_h, &msgs_left))) {
if (msg->msg == CURLMSG_DONE) {
ret = curl_easy_getinfo(msg->easy_handle, CURLINFO_RESPONSE_CODE, &http_code);
if (ret != CURLM_OK) {
syslog(LOG_ERR, "Couldn't send JSON message (message is lost): %s.", curl_easy_strerror(ret));
}
if (http_code > HTTP_CODE_OK) {
syslog(LOG_ERR, "Couldn't send JSON message (message is lost): HTTP error code %ld.", http_code);
}
}
}
/* cURL will set this to 0 when there is no transfer left to process,
* signaling we can sent the next message. list_check_queue() will insert the next message from the queue
* into the multi_h.
* If there's no message in the queue, we bail for now.
*/
if (curl_nr_h == 0) {
curl_nr_h = -1;
if (list_check_queue()) {
return;
}
}
FD_ZERO(&r);
FD_ZERO(&w);
FD_ZERO(&e);
/* With cURL you get the timeout you have to wait back from the library, so we use that for the select() call */
ret = curl_multi_timeout(multi_h, &curl_timeout);
if (ret != CURLM_OK) {
syslog(LOG_ERR, "%s", curl_multi_strerror(ret));
}
timeout.tv_sec = 0;
timeout.tv_usec = 100000;
if (curl_timeout >= 0) {
timeout.tv_sec = curl_timeout / 1000;
if (timeout.tv_sec > 1)
timeout.tv_sec = 1;
else
timeout.tv_usec = (curl_timeout % 1000) * 1000;
}
ret = curl_multi_fdset(multi_h, &r, &w, &e, &maxfd);
if (ret != CURLM_OK) {
syslog(LOG_ERR, "%s", curl_multi_strerror(ret));
return;
}
rc = select(maxfd+1, &r, &w, &e, &timeout);
switch(rc) {
case -1:
syslog(LOG_ERR, "%s", strerror(errno));
break;
case 0:
default:
/* This also sets curl_nr_h to exactly 0 if all the handles have been processed. */
while ((ret = curl_multi_perform(multi_h, &curl_nr_h)) && (ret == CURLM_CALL_MULTI_PERFORM)) {
continue;
}
if (ret != CURLM_OK) {
syslog(LOG_ERR, "%s", curl_multi_strerror(ret));
}
break;
}
}
static void handle_event(auparse_state_t *au,
auparse_cb_event_t cb_event_type, void *user_data);
static void int_handler(int sig)
{
if (sig_stop == 1) {
fprintf(stderr, "Repeated keyboard interrupt signal, forcing unclean program termination.\n");
exit(127);
}
sig_stop = 1;
}
static void term_handler(int sig)
{
sig_stop = 1;
}
static void hup_handler(int sig)
{
sig_hup = 1;
}
static void reload_config(void)
{
sig_hup = 0;
}
#ifdef REORDER_HACK
/*
* Hack to reorder input
* libaudit's auparse seems not to correlate messages correctly if event ids are out of sequence, ex (event id are
* 418143181 and 418143182):
* type=EXECVE msg=audit(1418253698.016:418143181): argc=3 a0="sh" a1="-c" a2=[redacted]
* type=EXECVE msg=audit(1418253698.016:418143182): argc=3 a0="sh" a1="-c" a2=[redacted]
* type=CWD msg=audit(1418253698.016:418143181): cwd="/opt/observium"
* type=CWD msg=audit(1418253698.016:418143182): cwd="/opt/observium"
*
* This hack sort them back so that event ids are back to back like this:
* type=EXECVE msg=audit(1418253698.016:418143181): argc=3 a0="sh" a1="-c" a2=[redacted]
* type=CWD msg=audit(1418253698.016:418143181): cwd="/opt/observium"
* type=EXECVE msg=audit(1418253698.016:418143182): argc=3 a0="sh" a1="-c" a2=[redacted]
* type=CWD msg=audit(1418253698.016:418143182): cwd="/opt/observium"
*
* Without the hack, when the event id correlation fails, auparse would only return the parsed event until the point of
* failure (so basically half of the message will be missing from the event/fields will be empty...)
*
* WARNING: The hack relies on properly null terminated strings here and there and doesn't do much bound checking other
* than that. Be careful.
* NOTE: This hack is only necessary when you can't fix libaudit easily, obviously. It's neither nice neither all that fast.
*/
/* count occurences of c in *in */
unsigned int strcharc(char *in, char c)
{
unsigned int i = 0;
for (i = 0; in[i]; in[i] == c ? i++ : *in++);
return i;
}
static int eventcmp(const void *p1, const void *p2)
{
char *s1, *s2;
char *a1, *a2;
int i;
s1 = *(char * const*)p1;
s2 = *(char * const*)p2;
if (!s1 || !s2)
return 0;
a1 = s1;
i = 0;
while (a1[0] != ':' && a1[0] != '\0' && i < MAX_AUDIT_MESSAGE_LENGTH) {
i++;
a1++;
}
a2 = s2;
i = 0;
while (a2[0] != ':' && a2[0] != '\0' && i < MAX_AUDIT_MESSAGE_LENGTH) {
i++;
a2++;
}
return strcmp(a1, a2);
}
size_t reorder_input_hack(char **sorted_tmp, char *tmp)
{
unsigned int lines = 0;
unsigned int llen = 0;
size_t flen = 0;
unsigned int i = 0;
lines = strcharc(tmp, '\n');
char *buf[lines];
char *line;
char *saved;
line = strtok_r(tmp, "\n", &saved);
if (!line) {
syslog(LOG_ERR, "message has no LF, message lost!");
return 0;
}
llen = strnlen(line, MAX_AUDIT_MESSAGE_LENGTH);
buf[i] = malloc(llen + 1);
if (!buf[i]) {
*sorted_tmp = tmp;
syslog(LOG_ERR, "reorder_input_hack() malloc failed won't reorder");
return strnlen(tmp, MAX_AUDIT_MESSAGE_LENGTH);
}
snprintf(buf[i], llen+1, "%s", line);
i++;
for (i; i < lines; i++) {
line = strtok_r(NULL, "\n", &saved);
if (!line) {
continue;
}
llen = strnlen(line, MAX_AUDIT_MESSAGE_LENGTH);
buf[i] = malloc(llen + 1);
if (!buf[i]) {
syslog(LOG_ERR, "reorder_input_hack() malloc failed partially reordering");
continue;
}
snprintf(buf[i], llen+1, "%s", line);
}
qsort(&buf, lines, sizeof(char *), eventcmp);
for (i = 0; i < lines; i++) {
flen += snprintf(*sorted_tmp+flen, MAX_AUDIT_MESSAGE_LENGTH, "%s\n", buf[i]);
if (buf[i]) {
free(buf[i]);
}
}
return flen;
}
#endif
int main(int argc, char *argv[])
{
char tmp[MAX_AUDIT_MESSAGE_LENGTH];
int len=0;
struct sigaction sa;
struct hostent *ht;
char nodename[64];
sa.sa_flags = 0;
sigemptyset(&sa.sa_mask);
sa.sa_handler = term_handler;
if (sigaction(SIGTERM, &sa, NULL) == -1)
return 1;
sa.sa_handler = int_handler;
if (sigaction(SIGINT, &sa, NULL) == -1)
return 1;
sa.sa_handler = hup_handler;
if (sigaction(SIGHUP, &sa, NULL) == -1)
return 1;
if (load_config(&config, CONFIG_FILE))
if (load_config(&config, CONFIG_FILE_LOCAL))
return 1;
openlog(PROGRAM_NAME, LOG_CONS, LOG_DAEMON);
if (gethostname(nodename, sizeof(nodename)-1)) {
snprintf(nodename, 10, "localhost");
}
nodename[sizeof(nodename)] = '\0';
ht = gethostbyname(nodename);
if (ht == NULL) {
hostname = strdup("localhost");
if (hostname == NULL)
return 1;
syslog(LOG_ALERT,
"gethostbyname could not find machine hostname, please fix this. Using %s as fallback. Error: %s",
hostname, hstrerror(h_errno));
} else {
hostname = strdup(ht->h_name);
if (hostname == NULL)
return 1;
}
au = auparse_init(AUSOURCE_FEED, NULL);
if (au == NULL) {
syslog(LOG_ERR, "could not initialize auparse");
return -1;
}
machine = audit_detect_machine();
if (machine < 0) {
return -1;
}
/* libcurl stuff */
if (curl_global_init(CURL_GLOBAL_ALL) != 0) {
syslog(LOG_ERR, "curl_global_init() failed");
return -1;
}
easy_h = curl_easy_init();
multi_h = curl_multi_init();
slist1 = NULL;
slist1 = curl_slist_append(slist1, "Content-Type:application/json");
if (!(easy_h && multi_h && slist1)) {
syslog(LOG_ERR, "cURL handles creation failed, this is fatal");
return -1;
}
#ifdef REORDER_HACK
int start = 0;
int stop = 0;
int i = 0;
char *full_str_tmp = malloc(NR_LINES_BUFFERED*MAX_AUDIT_MESSAGE_LENGTH);
char *sorted_tmp = malloc(NR_LINES_BUFFERED*MAX_AUDIT_MESSAGE_LENGTH);
if (!sorted_tmp || !full_str_tmp) {
syslog(LOG_ERR, "main() malloc failed for sorted_tmp || full_str_tmp, this is fatal");
return -1;
}
sorted_tmp[0] = '\0';
full_str_tmp[0] = '\0';
#endif
auparse_add_callback(au, handle_event, NULL, NULL);
syslog(LOG_INFO, "%s loaded\n", PROGRAM_NAME);
/* At this point we're initialized so we'll read stdin until closed and feed the data to auparse, which in turn will
* call our callback (handle_event) every time it finds a new complete message to parse.
*/
do {
/* NOTE: There's quite a few reasons for auparse_feed() from libaudit to fail parsing silently so we have to be careful here.
* Anything passed to it:
* - must have the same timestamp for a given event id. (kernel takes care of that, if not, you're out of luck).
* - must always be LF+NULL terminated ("\n\0"). (fgets takes care of that even thus it's not nearly as fast as fread).
* - must always have event ids in sequential order. (REORDER_HACK takes care of that, it also buffer lines, since, well, it needs to).
*/
while (fgets_unlocked(tmp, MAX_AUDIT_MESSAGE_LENGTH, stdin)) {
if (sig_hup)
reload_config();
if (sig_stop)
break;
len = strnlen(tmp, MAX_AUDIT_MESSAGE_LENGTH);
#ifdef REORDER_HACK
if (strncmp(tmp, "type=EOE", 8) == 0) {
stop++;
} else if (strncmp(tmp, "type=SYSCALL", 12) == 0) {
start++;
}
if (i > NR_LINES_BUFFERED || start != stop) {
strncat(full_str_tmp, tmp, len);
i++;
} else {
strncat(full_str_tmp, tmp, len);
len = reorder_input_hack(&sorted_tmp, full_str_tmp);
auparse_feed(au, sorted_tmp, len);
i = 0;
start = stop = 0;
sorted_tmp[0] = '\0';
full_str_tmp[0] = '\0';
}
#else
auparse_feed(au, tmp, len);
#endif
curl_perform();
}
if (feof(stdin))
break;
} while (sig_stop == 0);
auparse_flush_feed(au);
while (msg_queue_list)
curl_perform();
auparse_destroy(au);
curl_easy_cleanup(easy_h);
curl_multi_cleanup(multi_h);
curl_global_cleanup();
if (curl_logfile)
fclose(curl_logfile);
free_config(&config);
free(hostname);
#ifdef REORDER_HACK
free(sorted_tmp);
#endif
syslog(LOG_INFO, "%s unloaded\n", PROGRAM_NAME);
closelog();
return 0;
}
/*
* This function seeks to the specified record returning its type on succees
*/
static int goto_record_type(auparse_state_t *au, int type)
{
int cur_type;
auparse_first_record(au);
do {
cur_type = auparse_get_type(au);
if (cur_type == type) {
auparse_first_field(au);
return type; // Normal exit
}
} while (auparse_next_record(au) > 0);
return -1;
}
/* Removes quotes
* Remove CR and LF
* @const char *in: if NULL, no processing is done.
*/
char *unescape(const char *in)
{
if (in == NULL)
return NULL;
char *dst = (char *)in;
char *s = dst;
char *src = (char *)in;
char c;
while ((c = *src++) != '\0') {
if ((c == '"') || (c == '\n') || (c == '\r') || (c == '\t')
|| (c == '\b') || (c == '\f') || (c == '\\'))
continue;
*dst++ = c;
}
*dst++ = '\0';
return s;
}
/* Add a field to the json msg's details={}
* @attr_t *list: the attribute list to extend
* @const char *st: the attribute name to add
* @const char *val: the attribut value - if NULL, we won't add the field to the json message at all.
*/
attr_t *_json_add_attr(attr_t *list, const char *st, char *val, int freeme)
{
attr_t *new;
if (st == NULL || !strncmp(st, "(null)", 6) || val == NULL || !strncmp(val, "(null)", 6)) {
return list;
}
new = malloc(sizeof(attr_t));
if (!new) {
syslog(LOG_ERR, "json_add_attr() malloc failed attribute will be empty: %s", st);
return list;
}
snprintf(new->value, MAX_ATTR_SIZE, "\t\t\"%s\": \"%s\"", st, unescape(val));
new->next = list;
if (freeme) {
free(val);
}
return new;
}
/* Convenience wrappers for _json_add_attr */
attr_t *json_add_attr_free(attr_t *list, const char *st, char *val)
{
return _json_add_attr(list, st, val, 1);
}
attr_t *json_add_attr(attr_t *list, const char *st, const char *val)
{
return _json_add_attr(list, st, (char *)val, 0);
}
void json_del_attrs(attr_t *head)
{
attr_t *prev;
while (head) {
prev = head;
head = head->next;
free(prev);
}
}
/* Resolve uid to username - returns malloc'd value */
char *get_username(int uid)
{
size_t bufsize;
char *buf;
char *name;
struct passwd pwd;
struct passwd *result;
bufsize = sysconf(_SC_GETPW_R_SIZE_MAX);
if (bufsize == -1)
bufsize = 16384;
buf = (char *)alloca(bufsize);
if (!buf) {
return NULL;
}
if (uid == -1) {
return NULL;
}
if (getpwuid_r(uid, &pwd, buf, bufsize, &result) != 0) {
return NULL;
}
if (result == NULL) {
return NULL;
}
name = strdup(pwd.pw_name);
return name;
}
/* Resolve process name from pid */
char *get_proc_name(int pid)
{
char p[1024];
int ret;
static char proc[64];
FILE *fp;
snprintf(p, 512, "/proc/%d/status", pid);
fp = fopen(p, "r");
if (fp) {
ret = fscanf(fp, "Name: %63s", proc);
fclose(fp);
} else
return NULL;
if (ret == 0)
return NULL;
return proc;
}
/* This creates the JSON message we'll send over by deserializing the C struct into a char array
* the function name is rather historical, since this does not send to syslog anymore.
*/
void syslog_json_msg(struct json_msg_type json_msg)
{
attr_t *head = json_msg.details;
attr_t *prev;
queue_t *new_q;
int len;
if (msg_queue_list_size > MAX_CURL_QUEUE_SIZE) {
syslog(LOG_WARNING, "syslog_json_msg() MAX_CURL_QUEUE_SIZE of %u reached, message lost!", MAX_CURL_QUEUE_SIZE);
return;
}
new_q = malloc(sizeof(queue_t));
if (!new_q) {
syslog(LOG_ERR, "syslog_json_msg() new_q malloc() failed, message lost!");
return;
}
len = snprintf(new_q->msg, MAX_JSON_MSG_SIZE,
"{\n\
\"category\": \"%s\",\n\
\"summary\": \"%s\",\n\
\"severity\": \"%s\",\n\
\"hostname\": \"%s\",\n\
\"processid\": \"%i\",\n\
\"processname\": \"%s\",\n\
\"timestamp\": \"%s\",\n\
\"tags\": [\n\
\"%s\",\n\
\"%s\",\n\
\"audit\"\n\
],\n\
\"details\": {",
json_msg.category, json_msg.summary, json_msg.severity, json_msg.hostname, json_msg.processid,
PROGRAM_NAME, json_msg.timestamp, PROGRAM_NAME, STR(PROGRAM_VERSION));
while (head) {
len += snprintf(new_q->msg+len, MAX_JSON_MSG_SIZE-len, "\n%s,", head->value);
prev = head;
head = head->next;
free(prev);
if (head == NULL) {
new_q->msg[len-1] = '\n';
}
}
len += snprintf(new_q->msg+len, MAX_JSON_MSG_SIZE-len, " }\n}");
new_q->msg[MAX_JSON_MSG_SIZE-1] = '\0';
new_q->next = msg_queue_list;
msg_queue_list = new_q;
msg_queue_list_size++;
#ifdef DEBUG
printf("%s\n", new_q->msg);
#endif
}
/* The main event handling, parsing function */
static void handle_event(auparse_state_t *au,
auparse_cb_event_t cb_event_type, void *user_data)
{
int type, num=0;
struct json_msg_type json_msg = {
.category = NULL,
.hostname = hostname,
.processid = 0,
.processname = NULL,
.severity = "INFO",
.summary = NULL,
.timestamp = NULL,
.details = NULL,
};
typedef enum {
CAT_EXECVE,
CAT_WRITE,
CAT_PTRACE,
CAT_ATTR,
CAT_APPARMOR,
CAT_CHMOD,
CAT_CHOWN,
CAT_PROMISC,
CAT_TIME
} category_t;
category_t category;
const char *cwd = NULL, *argc = NULL, *cmd = NULL;
const char *path = NULL;
const char *dev = NULL;
const char *sys;
const char *syscall = NULL;
char fullcmd[MAX_ARG_LEN+1] = "\0";
char serial[64] = "\0";
time_t t;
struct tm *tmp;
char f[8];
int len, tmplen;
int argcount, i;
int promisc;
int havejson = 0;
/* wait until the lib gives up a full/ready event */
if (cb_event_type != AUPARSE_CB_EVENT_READY) {
return;
}
json_msg.timestamp = (char *)alloca(TS_LEN);
json_msg.summary = (char *)alloca(MAX_SUMMARY_LEN);
if (!json_msg.summary || !json_msg.timestamp) {
syslog(LOG_ERR, "handle_event() alloca failed, message lost!");
return;
}
while (auparse_goto_record_num(au, num) > 0) {
type = auparse_get_type(au);
if (!type)
continue;
if (!auparse_first_field(au))
continue;
t = auparse_get_time(au);
tmp = localtime(&t);
strftime(json_msg.timestamp, TS_LEN, "%FT%T%z", tmp);
snprintf(serial, TS_LEN-1, "%lu", auparse_get_serial(au));
json_msg.details = json_add_attr(json_msg.details, "auditserial", serial);
switch (type) {
case AUDIT_ANOM_PROMISCUOUS:
dev = auparse_find_field(au, "dev");
if (!dev)
return;
havejson = 1;
category = CAT_PROMISC;
json_msg.details = json_add_attr(json_msg.details, "dev", dev);
goto_record_type(au, type);
json_msg.details = json_add_attr(json_msg.details, "promiscious", auparse_find_field(au, "prom"));
promisc = auparse_get_field_int(au);
goto_record_type(au, type);
json_msg.details = json_add_attr(json_msg.details, "old_promicious", auparse_find_field(au, "old_prom"));
goto_record_type(au, type);
if (auparse_find_field(au, "auid")) {
json_msg.details = json_add_attr_free(json_msg.details, "originaluser",
get_username(auparse_get_field_int(au)));
json_msg.details = json_add_attr(json_msg.details, "originaluid", auparse_get_field_str(au));
}
goto_record_type(au, type);
if (auparse_find_field(au, "uid")) {
json_msg.details = json_add_attr_free(json_msg.details, "user", get_username(auparse_get_field_int(au)));
json_msg.details = json_add_attr(json_msg.details, "uid", auparse_get_field_str(au));
}
goto_record_type(au, type);
json_msg.details = json_add_attr(json_msg.details, "gid", auparse_find_field(au, "gid"));
goto_record_type(au, type);
json_msg.details = json_add_attr(json_msg.details, "session", auparse_find_field(au, "ses"));
goto_record_type(au, type);
break;
case AUDIT_AVC:
argc = auparse_find_field(au, "apparmor");
if (!argc)
return;
havejson = 1;
category = CAT_APPARMOR;
json_msg.details = json_add_attr(json_msg.details, "aaresult", auparse_get_field_str(au));
goto_record_type(au, type);
json_msg.summary = unescape(auparse_find_field(au, "info"));
goto_record_type(au, type);
json_msg.details = json_add_attr(json_msg.details, "aacoperation", auparse_find_field(au, "operation"));
goto_record_type(au, type);
json_msg.details = json_add_attr(json_msg.details, "aaprofile", auparse_find_field(au, "profile"));
goto_record_type(au, type);
json_msg.details = json_add_attr(json_msg.details, "aacommand", auparse_find_field(au, "comm"));
goto_record_type(au, type);
if (auparse_find_field(au, "parent"))
json_msg.details = json_add_attr(json_msg.details, "parentprocess",
get_proc_name(auparse_get_field_int(au)));
goto_record_type(au, type);
if (auparse_find_field(au, "pid"))
json_msg.details = json_add_attr(json_msg.details, "processname",
get_proc_name(auparse_get_field_int(au)));
goto_record_type(au, type);
json_msg.details = json_add_attr(json_msg.details, "aaerror", auparse_find_field(au, "error"));
goto_record_type(au, type);
json_msg.details = json_add_attr(json_msg.details, "aaname", auparse_find_field(au, "name"));
goto_record_type(au, type);
json_msg.details = json_add_attr(json_msg.details, "aasrcname", auparse_find_field(au, "srcname"));
goto_record_type(au, type);
json_msg.details = json_add_attr(json_msg.details, "aaflags", auparse_find_field(au, "flags"));
goto_record_type(au, type);
break;
case AUDIT_EXECVE:
argc = auparse_find_field(au, "argc");
if (argc)
argcount = auparse_get_field_int(au);
else
argcount = 0;
fullcmd[0] = '\0';
len = 0;
for (i = 0; i != argcount; i++) {
goto_record_type(au, type);
tmplen = snprintf(f, 7, "a%d", i);
f[tmplen] = '\0';
cmd = auparse_find_field(au, f);
cmd = auparse_interpret_field(au);
if (!cmd)
continue;
if (MAX_ARG_LEN-strlen(fullcmd) > strlen(cmd)) {
if (len == 0)
len += sprintf(fullcmd+len, "%s", cmd);
else
len += sprintf(fullcmd+len, " %s", cmd);
}
}
json_msg.details = json_add_attr(json_msg.details, "command", fullcmd);
break;
case AUDIT_CWD:
cwd = auparse_find_field(au, "cwd");
if (cwd) {
auparse_interpret_field(au);
json_msg.details = json_add_attr(json_msg.details, "cwd", auparse_find_field(au, "cwd"));
}
break;
case AUDIT_PATH:
path = auparse_find_field(au, "name");
json_msg.details = json_add_attr(json_msg.details, "path", path);
goto_record_type(au, type);
json_msg.details = json_add_attr(json_msg.details, "inode", auparse_find_field(au, "inode"));
goto_record_type(au, type);
json_msg.details = json_add_attr(json_msg.details, "dev", auparse_find_field(au, "dev"));
goto_record_type(au, type);
json_msg.details = json_add_attr(json_msg.details, "mode", auparse_find_field(au, "mode"));
goto_record_type(au, type);
json_msg.details = json_add_attr(json_msg.details, "ouid", auparse_find_field(au, "ouid"));
goto_record_type(au, type);
json_msg.details = json_add_attr(json_msg.details, "ogid", auparse_find_field(au, "ogid"));
goto_record_type(au, type);
json_msg.details = json_add_attr(json_msg.details, "rdev", auparse_find_field(au, "rdev"));
goto_record_type(au, type);
break;
case AUDIT_SYSCALL:
syscall = auparse_find_field(au, "syscall");
if (!syscall) {
json_del_attrs(json_msg.details);
return;
}
i = auparse_get_field_int(au);
sys = audit_syscall_to_name(i, machine);
if (!sys) {
syslog(LOG_DEBUG, "System call %u is not supported by %s", i, PROGRAM_NAME);
json_del_attrs(json_msg.details);
return;
}
json_msg.details = json_add_attr(json_msg.details, "processname", auparse_find_field(au, "comm"));
goto_record_type(au, type);
if (!strncmp(sys, "write", 5) || !strncmp(sys, "open", 4) || !strncmp(sys, "unlink", 6) || !strncmp(sys,
"rename", 6)) {
havejson = 1;
category = CAT_WRITE;
} else if (!strncmp(sys, "setxattr", 8)) {
havejson = 1;
category = CAT_ATTR;
} else if (!strncmp(sys, "chmod", 5)) {
havejson = 1;
category = CAT_CHMOD;
} else if (!strncmp(sys, "chown", 5) || !strncmp(sys, "fchown", 6)) {
havejson = 1;
category = CAT_CHOWN;
} else if (!strncmp(sys, "ptrace", 6)) {
havejson = 1;
category = CAT_PTRACE;
} else if (!strncmp(sys, "execve", 6)) {
havejson = 1;
category = CAT_EXECVE;
} else if (!strncmp(sys, "ioctl", 5)) {
category = CAT_PROMISC;
} else if (!strncmp(sys, "adjtimex", 8)) {
category = CAT_TIME;
} else {
syslog(LOG_INFO, "System call %u %s is not supported by %s", i, sys, PROGRAM_NAME);