/*
* Copyright (C) 2013-2020 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 <errno.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <dirent.h>
#ifndef _WIN32
#include <sys/time.h>
#include <sys/wait.h>
#include <sys/param.h>
#include <signal.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#endif
#include <pthread.h>
// libclamav
#include "clamav.h"
#include "others.h"
#include "scanners.h"
// shared
#include "idmef_logging.h"
#include "optparser.h"
#include "output.h"
#include "misc.h"
#include "clamd_others.h"
#include "scanner.h"
#include "shared.h"
#include "thrmgr.h"
#include "server.h"
#ifdef C_LINUX
dev_t procdev; /* /proc device */
#endif
extern int progexit;
extern time_t reloaded_time;
extern pthread_mutex_t reload_mutex;
void msg_callback(enum cl_msg severity, const char *fullmsg, const char *msg, void *ctx)
{
struct cb_context *c = ctx;
const char *filename = (c && c->filename) ? c->filename : "";
UNUSEDPARAM(fullmsg);
switch (severity) {
case CL_MSG_ERROR:
logg("^[LibClamAV] %s: %s", filename, msg);
break;
case CL_MSG_WARN:
logg("~[LibClamAV] %s: %s", filename, msg);
break;
case CL_MSG_INFO_VERBOSE:
logg("*[LibClamAV] %s: %s", filename, msg);
break;
default:
logg("$[LibClamAV] %s: %s", filename, msg);
break;
}
}
void hash_callback(int fd, unsigned long long size, const unsigned char *md5, const char *virname, void *ctx)
{
struct cb_context *c = ctx;
UNUSEDPARAM(fd);
UNUSEDPARAM(virname);
if (!c)
return;
c->virsize = size;
strncpy(c->virhash, (const char *)md5, 32);
c->virhash[32] = '\0';
}
void clamd_virus_found_cb(int fd, const char *virname, void *ctx)
{
struct cb_context *c = ctx;
struct scan_cb_data *d = c->scandata;
const char *fname;
UNUSEDPARAM(fd);
if (d == NULL)
return;
if (!(d->options->general & CL_SCAN_GENERAL_ALLMATCHES) && !(d->options->general & CL_SCAN_GENERAL_HEURISTIC_PRECEDENCE))
return;
if (virname == NULL)
return;
fname = (c && c->filename) ? c->filename : "(filename not set)";
if (virname) {
d->infected++;
conn_reply_virus(d->conn, fname, virname);
if (c->virsize > 0 && optget(d->opts, "ExtendedDetectionInfo")->enabled)
logg("~%s: %s(%s:%llu) FOUND\n", fname, virname, c->virhash, c->virsize);
logg("~%s: %s FOUND\n", fname, virname);
}
return;
}
#define BUFFSIZE 1024
cl_error_t scan_callback(STATBUF *sb, char *filename, const char *msg, enum cli_ftw_reason reason, struct cli_ftw_cbdata *data)
{
struct scan_cb_data *scandata = data->data;
const char *virname = NULL;
int ret;
int type = scandata->type;
struct cb_context context;
char *real_filename = NULL;
if (NULL != filename) {
if (CL_SUCCESS != cli_realpath((const char *)filename, &real_filename)) {
conn_reply_errno(scandata->conn, msg, "real-path check failed:");
logg("^Failed to determine real path for: %s\n", filename);
scandata->errors++;
return CL_SUCCESS;
}
free(filename);
filename = real_filename;
}
/* detect disconnected socket,
* this should NOT detect half-shutdown sockets (SHUT_WR) */
if (send(scandata->conn->sd, &ret, 0, 0) == -1 && errno != EINTR) {
logg("$Client disconnected while command was active!\n");
thrmgr_group_terminate(scandata->conn->group);
if (reason == visit_file)
free(filename);
return CL_BREAK;
}
if (thrmgr_group_need_terminate(scandata->conn->group)) {
logg("^Client disconnected while scanjob was active\n");
if (reason == visit_file)
free(filename);
return CL_BREAK;
}
scandata->total++;
switch (reason) {
case error_mem:
if (msg)
logg("!Memory allocation failed during cli_ftw() on %s\n",
msg);
else
logg("!Memory allocation failed during cli_ftw()\n");
scandata->errors++;
return CL_EMEM;
case error_stat:
conn_reply_errno(scandata->conn, msg, "lstat() failed:");
logg("^lstat() failed on: %s\n", msg);
scandata->errors++;
return CL_SUCCESS;
case warning_skipped_dir:
logg("^Directory recursion limit reached, skipping %s\n",
msg);
return CL_SUCCESS;
case warning_skipped_link:
logg("$Skipping symlink: %s\n", msg);
return CL_SUCCESS;
case warning_skipped_special:
if (msg == scandata->toplevel_path)
conn_reply(scandata->conn, msg, "Not supported file type", "ERROR");
logg("*Not supported file type: %s\n", msg);
return CL_SUCCESS;
case visit_directory_toplev:
return CL_SUCCESS;
case visit_file:
break;
}
#ifdef C_LINUX
/* check whether the file is excluded */
if (procdev && sb && (sb->st_dev == procdev)) {
free(filename);
return CL_SUCCESS;
}
#endif
if (sb && sb->st_size == 0) { /* empty file */
if (msg == scandata->toplevel_path)
conn_reply_single(scandata->conn, filename, "Empty file");
free(filename);
return CL_SUCCESS;
}
if (type == TYPE_MULTISCAN) {
client_conn_t *client_conn = (client_conn_t *)calloc(1, sizeof(struct client_conn_tag));
if (client_conn) {
client_conn->scanfd = -1;
client_conn->sd = scandata->odesc;
client_conn->filename = filename;
client_conn->cmdtype = COMMAND_MULTISCANFILE;
client_conn->term = scandata->conn->term;
client_conn->options = scandata->options;
client_conn->opts = scandata->opts;
client_conn->group = scandata->group;
if (cl_engine_addref(scandata->engine)) {
logg("!cl_engine_addref() failed\n");
free(filename);
free(client_conn);
return CL_EMEM;
} else {
client_conn->engine = scandata->engine;
pthread_mutex_lock(&reload_mutex);
client_conn->engine_timestamp = reloaded_time;
pthread_mutex_unlock(&reload_mutex);
if (!thrmgr_group_dispatch(scandata->thr_pool, scandata->group, client_conn, 1)) {
logg("!thread dispatch failed\n");
cl_engine_free(scandata->engine);
free(filename);
free(client_conn);
return CL_EMEM;
}
}
} else {
logg("!Can't allocate memory for client_conn\n");
scandata->errors++;
free(filename);
return CL_EMEM;
}
return CL_SUCCESS;
}
if (access(filename, R_OK)) {
if (conn_reply(scandata->conn, filename, "Access denied.", "ERROR") == -1) {
free(filename);
return CL_ETIMEOUT;
}
logg("*Access denied: %s\n", filename);
scandata->errors++;
free(filename);
return CL_SUCCESS;
}
thrmgr_setactivetask(filename, NULL);
context.filename = filename;
context.virsize = 0;
context.scandata = scandata;
ret = cl_scanfile_callback(filename, &virname, &scandata->scanned, scandata->engine, scandata->options, &context);
thrmgr_setactivetask(NULL, NULL);
if (thrmgr_group_need_terminate(scandata->conn->group)) {
free(filename);
logg("*Client disconnected while scanjob was active\n");
return ret == CL_ETIMEOUT ? ret : CL_BREAK;
}
if ((ret == CL_VIRUS) && (virname == NULL)) {
logg("*%s: reported CL_VIRUS but no virname returned!\n", filename);
ret = CL_EMEM;
}
if (ret == CL_VIRUS) {
if (scandata->options->general & CL_SCAN_GENERAL_ALLMATCHES || (scandata->infected && scandata->options->general & CL_SCAN_GENERAL_HEURISTIC_PRECEDENCE)) {
if (optget(scandata->opts, "PreludeEnable")->enabled) {
prelude_logging(filename, virname, context.virhash, context.virsize);
}
virusaction(filename, virname, scandata->opts);
} else {
scandata->infected++;
if (conn_reply_virus(scandata->conn, filename, virname) == -1) {
free(filename);
return CL_ETIMEOUT;
}
if (optget(scandata->opts, "PreludeEnable")->enabled) {
prelude_logging(filename, virname, context.virhash, context.virsize);
}
if (context.virsize && optget(scandata->opts, "ExtendedDetectionInfo")->enabled)
logg("~%s: %s(%s:%llu) FOUND\n", filename, virname, context.virhash, context.virsize);
else
logg("~%s: %s FOUND\n", filename, virname);
virusaction(filename, virname, scandata->opts);
}
} else if (ret != CL_CLEAN) {
scandata->errors++;
if (conn_reply(scandata->conn, filename, cl_strerror(ret), "ERROR") == -1) {
free(filename);
return CL_ETIMEOUT;
}
logg("~%s: %s ERROR\n", filename, cl_strerror(ret));
} else if (logok) {
logg("~%s: OK\n", filename);
}
free(filename);
if (ret == CL_EMEM) /* stop scanning */
return ret;
if (type == TYPE_SCAN) {
/* virus -> break */
return ret;
}
/* keep scanning always */
return CL_SUCCESS;
}
int scan_pathchk(const char *path, struct cli_ftw_cbdata *data)
{
struct scan_cb_data *scandata = data->data;
const struct optstruct *opt;
STATBUF statbuf;
if ((opt = optget(scandata->opts, "ExcludePath"))->enabled) {
while (opt) {
if (match_regex(path, opt->strarg) == 1) {
if (scandata->type != TYPE_MULTISCAN)
conn_reply_single(scandata->conn, path, "Excluded");
return 1;
}
opt = (const struct optstruct *)opt->nextarg;
}
}
if (!optget(scandata->opts, "CrossFilesystems")->enabled) {
if (CLAMSTAT(path, &statbuf) == 0) {
if (statbuf.st_dev != scandata->dev) {
if (scandata->type != TYPE_MULTISCAN)
conn_reply_single(scandata->conn, path, "Excluded (another filesystem)");
return 1;
}
}
}
return 0;
}
int scanfd(
const client_conn_t *conn,
unsigned long int *scanned,
const struct cl_engine *engine,
struct cl_scan_options *options,
const struct optstruct *opts,
int odesc,
int stream)
{
int ret, fd = conn->scanfd;
const char *virname = NULL;
STATBUF statbuf;
struct cb_context context;
char fdstr[32];
const char *reply_fdstr;
UNUSEDPARAM(odesc);
if (stream) {
struct sockaddr_in sa;
socklen_t salen = sizeof(sa);
if (getpeername(conn->sd, (struct sockaddr *)&sa, &salen) || salen > sizeof(sa) || sa.sin_family != AF_INET)
strncpy(fdstr, "instream(local)", sizeof(fdstr));
else
snprintf(fdstr, sizeof(fdstr), "instream(%s@%u)", inet_ntoa(sa.sin_addr), ntohs(sa.sin_port));
reply_fdstr = "stream";
} else {
snprintf(fdstr, sizeof(fdstr), "fd[%d]", fd);
reply_fdstr = fdstr;
}
if (FSTAT(fd, &statbuf) == -1 || !S_ISREG(statbuf.st_mode)) {
logg("%s: Not a regular file. ERROR\n", fdstr);
if (conn_reply(conn, reply_fdstr, "Not a regular file", "ERROR") == -1)
return CL_ETIMEOUT;
return -1;
}
thrmgr_setactivetask(fdstr, NULL);
context.filename = fdstr;
context.virsize = 0;
context.scandata = NULL;
ret = cl_scandesc_callback(fd, conn->filename, &virname, scanned, engine, options, &context);
thrmgr_setactivetask(NULL, NULL);
if (thrmgr_group_need_terminate(conn->group)) {
logg("*Client disconnected while scanjob was active\n");
return ret == CL_ETIMEOUT ? ret : CL_BREAK;
}
if (ret == CL_VIRUS) {
if (conn_reply_virus(conn, reply_fdstr, virname) == -1)
ret = CL_ETIMEOUT;
if (context.virsize && optget(opts, "ExtendedDetectionInfo")->enabled)
logg("%s: %s(%s:%llu) FOUND\n", fdstr, virname, context.virhash, context.virsize);
else
logg("%s: %s FOUND\n", fdstr, virname);
virusaction(reply_fdstr, virname, opts);
} else if (ret != CL_CLEAN) {
if (conn_reply(conn, reply_fdstr, cl_strerror(ret), "ERROR") == -1)
ret = CL_ETIMEOUT;
logg("%s: %s ERROR\n", fdstr, cl_strerror(ret));
} else {
if (conn_reply_single(conn, reply_fdstr, "OK") == CL_ETIMEOUT)
ret = CL_ETIMEOUT;
if (logok)
logg("%s: OK\n", fdstr);
}
return ret;
}
int scanstream(
int odesc,
unsigned long int *scanned,
const struct cl_engine *engine,
struct cl_scan_options *options,
const struct optstruct *opts,
char term)
{
int ret, sockfd, acceptd;
int tmpd, bread, retval, firsttimeout, timeout, btread;
unsigned int port = 0, portscan, min_port, max_port;
unsigned long int quota = 0, maxsize = 0;
short bound = 0;
const char *virname = NULL;
char buff[FILEBUFF];
char peer_addr[32];
struct cb_context context;
struct sockaddr_in server;
struct sockaddr_in peer;
socklen_t addrlen;
char *tmpname;
min_port = optget(opts, "StreamMinPort")->numarg;
max_port = optget(opts, "StreamMaxPort")->numarg;
/* search for a free port to bind to */
port = cli_rndnum(max_port - min_port);
bound = 0;
for (portscan = 0; portscan < 1000; portscan++) {
port = (port - 1) % (max_port - min_port + 1);
memset((char *)&server, 0, sizeof(server));
server.sin_family = AF_INET;
server.sin_port = htons(min_port + port);
server.sin_addr.s_addr = htonl(INADDR_ANY);
if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1)
continue;
if (bind(sockfd, (struct sockaddr *)&server, (socklen_t)sizeof(struct sockaddr_in)) == -1)
closesocket(sockfd);
else {
bound = 1;
break;
}
}
port += min_port;
timeout = optget(opts, "ReadTimeout")->numarg;
firsttimeout = optget(opts, "CommandReadTimeout")->numarg;
if (!bound) {
logg("!ScanStream: Can't find any free port.\n");
mdprintf(odesc, "Can't find any free port. ERROR%c", term);
return -1;
} else {
if (listen(sockfd, 1) == -1) {
logg("!ScanStream: listen() error on socket. Error returned is %s.\n", strerror(errno));
closesocket(sockfd);
return -1;
}
if (mdprintf(odesc, "PORT %u%c", port, term) <= 0) {
logg("!ScanStream: error transmitting port.\n");
closesocket(sockfd);
return -1;
}
}
retval = poll_fd(sockfd, firsttimeout, 0);
if (!retval || retval == -1) {
const char *reason = !retval ? "timeout" : "poll";
mdprintf(odesc, "Accept %s. ERROR%c", reason, term);
logg("!ScanStream %u: accept %s.\n", port, reason);
closesocket(sockfd);
return -1;
}
addrlen = sizeof(peer);
if ((acceptd = accept(sockfd, (struct sockaddr *)&peer, (socklen_t *)&addrlen)) == -1) {
closesocket(sockfd);
mdprintf(odesc, "accept() ERROR%c", term);
logg("!ScanStream %u: accept() failed.\n", port);
return -1;
}
*peer_addr = '\0';
inet_ntop(peer.sin_family, &peer.sin_addr, peer_addr, sizeof(peer_addr));
logg("*Accepted connection from %s on port %u, fd %d\n", peer_addr, port, acceptd);
if (cli_gentempfd(optget(opts, "TemporaryDirectory")->strarg, &tmpname, &tmpd)) {
shutdown(sockfd, 2);
closesocket(sockfd);
closesocket(acceptd);
mdprintf(odesc, "cli_gentempfd() failed. ERROR%c", term);
logg("!ScanStream(%s@%u): Can't create temporary file.\n", peer_addr, port);
return -1;
}
quota = maxsize = optget(opts, "StreamMaxLength")->numarg;
while ((retval = poll_fd(acceptd, timeout, 0)) == 1) {
/* only read up to max */
btread = (maxsize && (quota < sizeof(buff))) ? quota : sizeof(buff);
if (!btread) {
logg("^ScanStream(%s@%u): Size limit reached (max: %lu)\n", peer_addr, port, maxsize);
break; /* Scan what we have */
}
bread = recv(acceptd, buff, btread, 0);
if (bread <= 0)
break;
quota -= bread;
if (writen(tmpd, buff, bread) != bread) {
shutdown(sockfd, 2);
closesocket(sockfd);
closesocket(acceptd);
mdprintf(odesc, "Temporary file -> write ERROR%c", term);
logg("!ScanStream(%s@%u): Can't write to temporary file.\n", peer_addr, port);
close(tmpd);
if (!optget(opts, "LeaveTemporaryFiles")->enabled)
unlink(tmpname);
free(tmpname);
return -1;
}
}
switch (retval) {
case 0: /* timeout */
mdprintf(odesc, "read timeout ERROR%c", term);
logg("!ScanStream(%s@%u): read timeout.\n", peer_addr, port);
break;
case -1:
mdprintf(odesc, "read poll ERROR%c", term);
logg("!ScanStream(%s@%u): read poll failed.\n", peer_addr, port);
break;
}
if (retval == 1) {
lseek(tmpd, 0, SEEK_SET);
thrmgr_setactivetask(peer_addr, NULL);
context.filename = peer_addr;
context.virsize = 0;
context.scandata = NULL;
ret = cl_scandesc_callback(tmpd, tmpname, &virname, scanned, engine, options, &context);
thrmgr_setactivetask(NULL, NULL);
} else {
ret = -1;
}
close(tmpd);
if (!optget(opts, "LeaveTemporaryFiles")->enabled)
unlink(tmpname);
free(tmpname);
closesocket(acceptd);
closesocket(sockfd);
if (ret == CL_VIRUS) {
if (context.virsize && optget(opts, "ExtendedDetectionInfo")->enabled) {
mdprintf(odesc, "stream: %s(%s:%llu) FOUND%c", virname, context.virhash, context.virsize, term);
logg("stream(%s@%u): %s(%s:%llu) FOUND\n", peer_addr, port, virname, context.virhash, context.virsize);
} else {
mdprintf(odesc, "stream: %s FOUND%c", virname, term);
logg("stream(%s@%u): %s FOUND\n", peer_addr, port, virname);
}
virusaction("stream", virname, opts);
} else if (ret != CL_CLEAN) {
if (retval == 1) {
mdprintf(odesc, "stream: %s ERROR%c", cl_strerror(ret), term);
logg("stream(%s@%u): %s ERROR\n", peer_addr, port, cl_strerror(ret));
}
} else {
mdprintf(odesc, "stream: OK%c", term);
if (logok)
logg("stream(%s@%u): OK\n", peer_addr, port);
}
return ret;
}