/*
* Copyright (C) 2013-2019 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
* Copyright (C) 2007-2013 Sourcefire, Inc.
*
* Authors: Tomasz Kojm, Török Edvin
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* 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., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301, USA.
*/
#if HAVE_CONFIG_H
#include "clamav-config.h"
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <sys/types.h>
#include <dirent.h>
#ifndef _WIN32
#include <sys/socket.h>
#ifdef HAVE_SYS_SELECT_H
#include <sys/select.h>
#endif
#ifdef HAVE_FD_PASSING
#ifdef HAVE_SYS_UIO_H
#include <sys/uio.h>
#endif
#endif
#include <sys/time.h>
#endif
#include <pthread.h>
#include <time.h>
#include <errno.h>
#include <stddef.h>
#include <limits.h>
#include "libclamav/clamav.h"
#include "libclamav/str.h"
#include "libclamav/others.h"
#include "shared/optparser.h"
#include "shared/output.h"
#include "shared/misc.h"
#include "others.h"
#include "scanner.h"
#include "server.h"
#include "session.h"
#include "thrmgr.h"
#ifndef HAVE_FDPASSING
#define FEATURE_FDPASSING 0
#else
#define FEATURE_FDPASSING 1
#endif
static struct {
const char *cmd;
const size_t len;
enum commands cmdtype;
int need_arg;
int support_old;
int enabled;
} commands[] = {
{CMD1, sizeof(CMD1) - 1, COMMAND_SCAN, 1, 1, 0},
{CMD3, sizeof(CMD3) - 1, COMMAND_SHUTDOWN, 0, 1, 0},
{CMD4, sizeof(CMD4) - 1, COMMAND_RELOAD, 0, 1, 0},
{CMD5, sizeof(CMD5) - 1, COMMAND_PING, 0, 1, 0},
{CMD6, sizeof(CMD6) - 1, COMMAND_CONTSCAN, 1, 1, 0},
/* must be before VERSION, because they share common prefix! */
{CMD18, sizeof(CMD18) - 1, COMMAND_COMMANDS, 0, 0, 1},
{CMD7, sizeof(CMD7) - 1, COMMAND_VERSION, 0, 1, 1},
{CMD8, sizeof(CMD8) - 1, COMMAND_STREAM, 0, 1, 1},
{CMD10, sizeof(CMD10) - 1, COMMAND_END, 0, 0, 1},
{CMD11, sizeof(CMD11) - 1, COMMAND_SHUTDOWN, 0, 1, 1},
{CMD13, sizeof(CMD13) - 1, COMMAND_MULTISCAN, 1, 1, 1},
{CMD14, sizeof(CMD14) - 1, COMMAND_FILDES, 0, 1, FEATURE_FDPASSING},
{CMD15, sizeof(CMD15) - 1, COMMAND_STATS, 0, 0, 1},
{CMD16, sizeof(CMD16) - 1, COMMAND_IDSESSION, 0, 0, 1},
{CMD17, sizeof(CMD17) - 1, COMMAND_INSTREAM, 0, 0, 1},
{CMD19, sizeof(CMD19) - 1, COMMAND_DETSTATSCLEAR, 0, 1, 1},
{CMD20, sizeof(CMD20) - 1, COMMAND_DETSTATS, 0, 1, 1},
{CMD21, sizeof(CMD21) - 1, COMMAND_ALLMATCHSCAN, 1, 0, 1}};
enum commands parse_command(const char *cmd, const char **argument, int oldstyle)
{
size_t i;
*argument = NULL;
for (i = 0; i < sizeof(commands) / sizeof(commands[0]); i++) {
const size_t len = commands[i].len;
if (!strncmp(cmd, commands[i].cmd, len)) {
const char *arg = cmd + len;
if (commands[i].need_arg) {
if (!*arg) { /* missing argument */
logg("$Command %s missing argument!\n", commands[i].cmd);
return COMMAND_UNKNOWN;
}
*argument = arg + 1;
} else {
if (*arg) { /* extra stuff after command */
logg("$Command %s has trailing garbage!\n", commands[i].cmd);
return COMMAND_UNKNOWN;
}
*argument = NULL;
}
if (oldstyle && !commands[i].support_old) {
logg("$Command sent as old-style when not supported: %s\n", commands[i].cmd);
return COMMAND_UNKNOWN;
}
return commands[i].cmdtype;
}
}
return COMMAND_UNKNOWN;
}
int conn_reply_single(const client_conn_t *conn, const char *path, const char *status)
{
if (conn->id) {
if (path)
return mdprintf(conn->sd, "%u: %s: %s%c", conn->id, path, status, conn->term);
return mdprintf(conn->sd, "%u: %s%c", conn->id, status, conn->term);
}
if (path)
return mdprintf(conn->sd, "%s: %s%c", path, status, conn->term);
return mdprintf(conn->sd, "%s%c", status, conn->term);
}
int conn_reply(const client_conn_t *conn, const char *path,
const char *msg, const char *status)
{
if (conn->id) {
if (path)
return mdprintf(conn->sd, "%u: %s: %s %s%c", conn->id, path, msg,
status, conn->term);
return mdprintf(conn->sd, "%u: %s %s%c", conn->id, msg, status,
conn->term);
}
if (path)
return mdprintf(conn->sd, "%s: %s %s%c", path, msg, status, conn->term);
return mdprintf(conn->sd, "%s %s%c", msg, status, conn->term);
}
int conn_reply_virus(const client_conn_t *conn, const char *file,
const char *virname)
{
if (conn->id) {
return mdprintf(conn->sd, "%u: %s: %s FOUND%c", conn->id, file, virname,
conn->term);
}
return mdprintf(conn->sd, "%s: %s FOUND%c", file, virname, conn->term);
}
int conn_reply_error(const client_conn_t *conn, const char *msg)
{
return conn_reply(conn, NULL, msg, "ERROR");
}
#define BUFFSIZE 1024
int conn_reply_errno(const client_conn_t *conn, const char *path,
const char *msg)
{
char err[BUFFSIZE + sizeof(". ERROR")];
cli_strerror(errno, err, BUFFSIZE - 1);
strcat(err, ". ERROR");
return conn_reply(conn, path, msg, err);
}
/* returns
* -1 on fatal error (shutdown)
* 0 on ok
* >0 errors encountered
*/
int command(client_conn_t *conn, int *virus)
{
int desc = conn->sd;
struct cl_engine *engine = conn->engine;
struct cl_scan_options *options = conn->options;
const struct optstruct *opts = conn->opts;
enum scan_type type = TYPE_INIT;
int maxdirrec;
int ret = 0;
int flags = CLI_FTW_STD;
struct scan_cb_data scandata;
struct cli_ftw_cbdata data;
unsigned ok, error, total;
STATBUF sb;
jobgroup_t *group = NULL;
if (thrmgr_group_need_terminate(conn->group)) {
logg("$Client disconnected while command was active\n");
if (conn->scanfd != -1)
close(conn->scanfd);
return 1;
}
thrmgr_setactiveengine(engine);
data.data = &scandata;
memset(&scandata, 0, sizeof(scandata));
scandata.id = conn->id;
scandata.group = conn->group;
scandata.odesc = desc;
scandata.conn = conn;
scandata.options = options;
scandata.engine = engine;
scandata.opts = opts;
scandata.thr_pool = conn->thrpool;
scandata.toplevel_path = conn->filename;
switch (conn->cmdtype) {
case COMMAND_SCAN:
thrmgr_setactivetask(NULL, "SCAN");
type = TYPE_SCAN;
break;
case COMMAND_CONTSCAN:
thrmgr_setactivetask(NULL, "CONTSCAN");
type = TYPE_CONTSCAN;
break;
case COMMAND_MULTISCAN: {
int multiscan, max, alive;
/* use MULTISCAN only for directories (bb #1869) */
if (CLAMSTAT(conn->filename, &sb) == 0 &&
!S_ISDIR(sb.st_mode)) {
thrmgr_setactivetask(NULL, "CONTSCAN");
type = TYPE_CONTSCAN;
break;
}
pthread_mutex_lock(&conn->thrpool->pool_mutex);
multiscan = conn->thrpool->thr_multiscan;
max = conn->thrpool->thr_max;
if (multiscan + 1 < max)
conn->thrpool->thr_multiscan = multiscan + 1;
else {
alive = conn->thrpool->thr_alive;
ret = -1;
}
pthread_mutex_unlock(&conn->thrpool->pool_mutex);
if (ret) {
/* multiscan has 1 control thread, so there needs to be at least
1 threads that is a non-multiscan controlthread to scan and
make progress. */
logg("^Not enough threads for multiscan. Max: %d, Alive: %d, Multiscan: %d+1\n",
max, alive, multiscan);
conn_reply(conn, conn->filename, "Not enough threads for multiscan. Increase MaxThreads.", "ERROR");
return 1;
}
flags &= ~CLI_FTW_NEED_STAT;
thrmgr_setactivetask(NULL, "MULTISCAN");
type = TYPE_MULTISCAN;
scandata.group = group = thrmgr_group_new();
if (!group) {
if (optget(opts, "ExitOnOOM")->enabled)
return -1;
else
return 1;
}
break;
}
case COMMAND_MULTISCANFILE:
thrmgr_setactivetask(NULL, "MULTISCANFILE");
scandata.group = NULL;
scandata.type = TYPE_SCAN;
scandata.thr_pool = NULL;
/* TODO: check ret value */
ret = scan_callback(NULL, conn->filename, conn->filename, visit_file, &data); /* callback freed it */
conn->filename = NULL;
*virus = scandata.infected;
if (ret == CL_BREAK) {
thrmgr_group_terminate(conn->group);
return 1;
}
return scandata.errors > 0 ? scandata.errors : 0;
case COMMAND_FILDES:
thrmgr_setactivetask(NULL, "FILDES");
#ifdef HAVE_FD_PASSING
if (conn->scanfd == -1) {
conn_reply_error(conn, "FILDES: didn't receive file descriptor.");
return 1;
} else {
ret = scanfd(conn, NULL, engine, options, opts, desc, 0);
if (ret == CL_VIRUS) {
*virus = 1;
ret = 0;
} else if (ret == CL_EMEM) {
if (optget(opts, "ExitOnOOM")->enabled)
ret = -1;
else
ret = 1;
} else if (ret == CL_ETIMEOUT) {
thrmgr_group_terminate(conn->group);
ret = 1;
} else
ret = 0;
logg("$Closed fd %d\n", conn->scanfd);
close(conn->scanfd);
}
return ret;
#else
conn_reply_error(conn, "FILDES support not compiled in.");
close(conn->scanfd);
return 0;
#endif
case COMMAND_STATS:
thrmgr_setactivetask(NULL, "STATS");
if (conn->group)
mdprintf(desc, "%u: ", conn->id);
thrmgr_printstats(desc, conn->term);
return 0;
case COMMAND_STREAM:
thrmgr_setactivetask(NULL, "STREAM");
ret = scanstream(desc, NULL, engine, options, opts, conn->term);
if (ret == CL_VIRUS)
*virus = 1;
if (ret == CL_EMEM) {
if (optget(opts, "ExitOnOOM")->enabled)
return -1;
else
return 1;
}
return 0;
case COMMAND_INSTREAMSCAN:
thrmgr_setactivetask(NULL, "INSTREAM");
ret = scanfd(conn, NULL, engine, options, opts, desc, 1);
if (ret == CL_VIRUS) {
*virus = 1;
ret = 0;
} else if (ret == CL_EMEM) {
if (optget(opts, "ExitOnOOM")->enabled)
ret = -1;
else
ret = 1;
} else if (ret == CL_ETIMEOUT) {
thrmgr_group_terminate(conn->group);
ret = 1;
} else
ret = 0;
if (ftruncate(conn->scanfd, 0) == -1) {
/* not serious, we're going to close it and unlink it anyway */
logg("*ftruncate failed: %d\n", errno);
}
close(conn->scanfd);
conn->scanfd = -1;
cli_unlink(conn->filename);
return ret;
case COMMAND_ALLMATCHSCAN:
if (!optget(opts, "AllowAllMatchScan")->enabled) {
logg("$Rejecting ALLMATCHSCAN command.\n");
conn_reply(conn, conn->filename, "ALLMATCHSCAN command disabled by clamd configuration.", "ERROR");
return 1;
}
thrmgr_setactivetask(NULL, "ALLMATCHSCAN");
scandata.options->general |= CL_SCAN_GENERAL_ALLMATCHES;
type = TYPE_SCAN;
break;
default:
logg("!Invalid command dispatched: %d\n", conn->cmdtype);
return 1;
}
scandata.type = type;
maxdirrec = optget(opts, "MaxDirectoryRecursion")->numarg;
if (optget(opts, "FollowDirectorySymlinks")->enabled)
flags |= CLI_FTW_FOLLOW_DIR_SYMLINK;
if (optget(opts, "FollowFileSymlinks")->enabled)
flags |= CLI_FTW_FOLLOW_FILE_SYMLINK;
if (!optget(opts, "CrossFilesystems")->enabled)
if (CLAMSTAT(conn->filename, &sb) == 0)
scandata.dev = sb.st_dev;
ret = cli_ftw(conn->filename, flags, maxdirrec ? maxdirrec : INT_MAX, scan_callback, &data, scan_pathchk);
if (ret == CL_EMEM) {
if (optget(opts, "ExitOnOOM")->enabled)
return -1;
else
return 1;
}
if (scandata.group && type == TYPE_MULTISCAN) {
thrmgr_group_waitforall(group, &ok, &error, &total);
pthread_mutex_lock(&conn->thrpool->pool_mutex);
conn->thrpool->thr_multiscan--;
pthread_mutex_unlock(&conn->thrpool->pool_mutex);
} else {
error = scandata.errors;
total = scandata.total;
ok = total - error - scandata.infected;
}
if (ok + error == total && (error != total)) {
if (conn_reply_single(conn, conn->filename, "OK") == -1)
ret = CL_ETIMEOUT;
}
*virus = total - (ok + error);
if (ret == CL_ETIMEOUT)
thrmgr_group_terminate(conn->group);
return error;
}
static int dispatch_command(client_conn_t *conn, enum commands cmd, const char *argument)
{
int ret = 0;
int bulk;
client_conn_t *dup_conn = (client_conn_t *)malloc(sizeof(struct client_conn_tag));
if (!dup_conn) {
logg("!Can't allocate memory for client_conn\n");
return -1;
}
memcpy(dup_conn, conn, sizeof(*conn));
dup_conn->cmdtype = cmd;
if (cl_engine_addref(dup_conn->engine)) {
logg("!cl_engine_addref() failed\n");
free(dup_conn);
return -1;
}
dup_conn->scanfd = -1;
bulk = 1;
switch (cmd) {
case COMMAND_FILDES:
if (conn->scanfd == -1) {
conn_reply_error(dup_conn, "No file descriptor received.");
ret = 1;
}
dup_conn->scanfd = conn->scanfd;
/* consume FD */
conn->scanfd = -1;
break;
case COMMAND_SCAN:
case COMMAND_CONTSCAN:
case COMMAND_MULTISCAN:
case COMMAND_ALLMATCHSCAN:
dup_conn->filename = cli_strdup_to_utf8(argument);
if (!dup_conn->filename) {
logg("!Failed to allocate memory for filename\n");
ret = -1;
}
break;
case COMMAND_INSTREAMSCAN:
dup_conn->scanfd = conn->scanfd;
conn->scanfd = -1;
break;
case COMMAND_STREAM:
case COMMAND_STATS:
/* not a scan command, don't queue to bulk */
bulk = 0;
/* just dispatch the command */
break;
default:
logg("!Invalid command dispatch: %d\n", cmd);
ret = -2;
break;
}
if (!dup_conn->group)
bulk = 0;
if (!ret && !thrmgr_group_dispatch(dup_conn->thrpool, dup_conn->group, dup_conn, bulk)) {
logg("!thread dispatch failed\n");
ret = -2;
}
if (ret) {
cl_engine_free(dup_conn->engine);
free(dup_conn);
}
return ret;
}
static int print_ver(int desc, char term, const struct cl_engine *engine)
{
uint32_t ver;
ver = cl_engine_get_num(engine, CL_ENGINE_DB_VERSION, NULL);
if (ver) {
char timestr[32];
const char *tstr;
time_t t;
t = cl_engine_get_num(engine, CL_ENGINE_DB_TIME, NULL);
tstr = cli_ctime(&t, timestr, sizeof(timestr));
/* cut trailing \n */
timestr[strlen(tstr) - 1] = '\0';
return mdprintf(desc, "ClamAV %s/%u/%s%c", get_version(), (unsigned int)ver, tstr, term);
}
return mdprintf(desc, "ClamAV %s%c", get_version(), term);
}
static void print_commands(int desc, char term, const struct cl_engine *engine)
{
unsigned i, n;
const char *engine_ver = cl_retver();
const char *clamd_ver = get_version();
if (strcmp(engine_ver, clamd_ver)) {
mdprintf(desc, "ENGINE VERSION MISMATCH: %s != %s. ERROR%c",
engine_ver, clamd_ver, term);
return;
}
print_ver(desc, '|', engine);
mdprintf(desc, " COMMANDS:");
n = sizeof(commands) / sizeof(commands[0]);
for (i = 0; i < n; i++) {
mdprintf(desc, " %s", commands[i].cmd);
}
mdprintf(desc, "%c", term);
}
/* returns:
* <0 for error
* -1 out of memory
* -2 other
* 0 for async dispatched
* 1 for command completed (connection can be closed)
*/
int execute_or_dispatch_command(client_conn_t *conn, enum commands cmd, const char *argument)
{
int desc = conn->sd;
char term = conn->term;
const struct cl_engine *engine = conn->engine;
/* execute commands that can be executed quickly on the recvloop thread,
* these must:
* - not involve any operation that can block for a long time, such as disk
* I/O
* - send of atomic message is allowed.
* Dispatch other commands */
if (conn->group) {
switch (cmd) {
case COMMAND_FILDES:
case COMMAND_SCAN:
case COMMAND_END:
case COMMAND_INSTREAM:
case COMMAND_INSTREAMSCAN:
case COMMAND_VERSION:
case COMMAND_PING:
case COMMAND_STATS:
case COMMAND_COMMANDS:
/* These commands are accepted inside IDSESSION */
break;
default:
/* these commands are not recognized inside an IDSESSION */
conn_reply_error(conn, "Command invalid inside IDSESSION.");
logg("$SESSION: command is not valid inside IDSESSION: %d\n", cmd);
conn->group = NULL;
return 1;
}
}
switch (cmd) {
case COMMAND_SHUTDOWN:
pthread_mutex_lock(&exit_mutex);
progexit = 1;
pthread_mutex_unlock(&exit_mutex);
return 1;
case COMMAND_RELOAD:
pthread_mutex_lock(&reload_mutex);
reload = 1;
pthread_mutex_unlock(&reload_mutex);
mdprintf(desc, "RELOADING%c", term);
/* we set reload flag, and we'll reload before closing the
* connection */
return 1;
case COMMAND_PING:
if (conn->group)
mdprintf(desc, "%u: PONG%c", conn->id, term);
else
mdprintf(desc, "PONG%c", term);
return conn->group ? 0 : 1;
case COMMAND_VERSION: {
if (conn->group)
mdprintf(desc, "%u: ", conn->id);
print_ver(desc, conn->term, engine);
return conn->group ? 0 : 1;
}
case COMMAND_COMMANDS: {
if (conn->group)
mdprintf(desc, "%u: ", conn->id);
print_commands(desc, conn->term, engine);
return conn->group ? 0 : 1;
}
case COMMAND_DETSTATSCLEAR: {
/* TODO: tell client this command has been removed */
return 1;
}
case COMMAND_DETSTATS: {
/* TODO: tell client this command has been removed */
return 1;
}
case COMMAND_INSTREAM: {
int rc = cli_gentempfd(optget(conn->opts, "TemporaryDirectory")->strarg, &conn->filename, &conn->scanfd);
if (rc != CL_SUCCESS)
return rc;
conn->quota = optget(conn->opts, "StreamMaxLength")->numarg;
conn->mode = MODE_STREAM;
return 0;
}
case COMMAND_STREAM:
case COMMAND_MULTISCAN:
case COMMAND_CONTSCAN:
case COMMAND_STATS:
case COMMAND_FILDES:
case COMMAND_SCAN:
case COMMAND_INSTREAMSCAN:
case COMMAND_ALLMATCHSCAN:
return dispatch_command(conn, cmd, argument);
case COMMAND_IDSESSION:
conn->group = thrmgr_group_new();
if (!conn->group)
return CL_EMEM;
return 0;
case COMMAND_END:
if (!conn->group) {
/* end without idsession? */
conn_reply_single(conn, NULL, "UNKNOWN COMMAND");
return 1;
}
/* need to close connection if we were last in group */
return 1;
/*case COMMAND_UNKNOWN:*/
default:
conn_reply_single(conn, NULL, "UNKNOWN COMMAND");
return 1;
}
}