clamav/clamonacc/client/protocol.c
2024-01-22 11:27:17 -05:00

465 lines
13 KiB
C

/*
* Copyright (C) 2015-2024 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
* Copyright (C) 2009 Sourcefire, Inc.
*
* Authors: Tomasz Kojm, aCaB, Mickey Sola
*
* 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
#if defined(C_SOLARIS)
#ifndef __EXTENSIONS__
#define __EXTENSIONS__
#endif
#endif
/* must be first because it may define _XOPEN_SOURCE */
#include "fdpassing.h"
#include <stdio.h>
#include <curl/curl.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <string.h>
#include <errno.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/types.h>
#ifdef HAVE_SYS_SELECT_H
#include <sys/select.h>
#endif
#ifndef _WIN32
#include <arpa/inet.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <netdb.h>
#endif
// libclamav
#include "clamav.h"
#include "others.h"
// common
#include "actions.h"
#include "output.h"
#include "misc.h"
#include "clamdcom.h"
#include "communication.h"
#include "protocol.h"
#include "client.h"
#include "socket.h"
static const char *scancmd[] = {"CONTSCAN", "MULTISCAN", "INSTREAM", "FILDES", "ALLMATCHSCAN"};
/* Issues an INSTREAM command to clamd and streams the given file
* Returns >0 on success, 0 soft fail, -1 hard fail */
static int onas_send_stream(CURL *curl, const char *filename, int fd, int64_t timeout, uint64_t maxstream)
{
uint32_t buf[BUFSIZ / sizeof(uint32_t)];
uint64_t len;
int ret = 1;
int close_flag = 0;
STATBUF statbuf;
uint64_t bytesRead = 0;
const char zINSTREAM[] = "zINSTREAM";
if (-1 == fd) {
if (NULL == filename) {
logg(LOGG_ERROR, "onas_send_stream: Invalid args, a filename or file descriptor must be provided.\n");
return 0;
} else {
if ((fd = safe_open(filename, O_RDONLY | O_BINARY)) < 0) {
logg(LOGG_DEBUG, "%s: Failed to open file. ERROR\n", filename);
return 0;
}
// logg(LOGG_INFO, "DEBUG: >>>>> fd is %d\n", fd);
close_flag = 1;
}
}
if (FSTAT(fd, &statbuf)) {
logg(LOGG_ERROR, "onas_send_stream: Invalid args, bad file descriptor.\n");
ret = -1;
goto strm_out;
}
if (S_ISDIR(statbuf.st_mode)) {
ret = 0;
goto strm_out;
}
if ((uint64_t)statbuf.st_size > maxstream) {
ret = 0;
goto strm_out;
}
if (onas_sendln(curl, zINSTREAM, sizeof(zINSTREAM), timeout)) {
ret = -1;
goto strm_out;
}
len = statbuf.st_size;
buf[0] = htonl(len);
if (onas_sendln(curl, (const char *)buf, sizeof(uint32_t), timeout)) {
ret = -1;
goto strm_out;
}
while (bytesRead < len) {
ssize_t ret = read(fd, buf, sizeof(buf));
if (ret < 0) {
logg(LOGG_ERROR, "Failed to read from %s.\n", filename ? filename : "FD");
ret = -1;
goto strm_out;
} else if (0 == ret) {
break;
}
bytesRead += ret;
if (onas_sendln(curl, (const char *)buf, ret, timeout)) {
ret = -1;
goto strm_out;
}
}
*buf = 0;
onas_sendln(curl, (const char *)buf, 4, timeout);
strm_out:
if (close_flag) {
close(fd);
}
return ret;
}
#ifdef HAVE_FD_PASSING
static int onas_send_fdpass(int sockd, int fd)
{
char dummy[] = "";
struct iovec iov[1];
struct msghdr msg;
struct cmsghdr *cmsg;
unsigned char fdbuf[CMSG_SPACE(sizeof(int))];
const char zFILDES[] = "zFILDES";
if (sendln(sockd, zFILDES, sizeof(zFILDES))) {
return -1;
}
iov[0].iov_base = dummy;
iov[0].iov_len = 1;
memset(&msg, 0, sizeof(msg));
msg.msg_control = fdbuf;
msg.msg_iov = iov;
msg.msg_iovlen = 1;
msg.msg_controllen = CMSG_LEN(sizeof(int));
cmsg = CMSG_FIRSTHDR(&msg);
cmsg->cmsg_len = CMSG_LEN(sizeof(int));
cmsg->cmsg_level = SOL_SOCKET;
cmsg->cmsg_type = SCM_RIGHTS;
*(int *)CMSG_DATA(cmsg) = fd;
if (sendmsg(sockd, &msg, 0) == -1) {
logg(LOGG_ERROR, "FD send failed: %s\n", strerror(errno));
return -1;
}
return 1;
}
/* Issues a FILDES command and pass a FD to clamd
* Returns >0 on success, 0 soft fail, -1 hard fail */
static int onas_fdpass(const char *filename, int fd, int sockd)
{
int ret = 1;
int close_flag = 0;
if (-1 == fd) {
if (filename) {
if ((fd = open(filename, O_RDONLY)) < 0) {
logg(LOGG_DEBUG, "%s: Failed to open file. ERROR\n", filename);
return 0;
}
close_flag = 1;
} else {
fd = -1;
}
}
if (sockd == -1) {
logg(LOGG_DEBUG, "ClamProto: error when getting socket descriptor\n");
ret = -1;
goto fd_out;
}
ret = onas_send_fdpass(sockd, fd);
if (ret < 0) {
logg(LOGG_DEBUG, "ClamProto: error when fdpassing\n");
ret = -1;
goto fd_out;
}
fd_out:
if (close_flag) {
close(fd);
}
return ret;
}
#endif
/* Sends a proper scan request to clamd and parses its replies
* This is used only in non IDSESSION mode
* Returns the number of infected files or -1 on error
* NOTE: filename may be NULL for STREAM scantype. */
int onas_dsresult(CURL *curl, int scantype, uint64_t maxstream, const char *filename, int fd, int64_t timeout, int *printok, int *errors, cl_error_t *ret_code)
{
int infected = 0, len = 0, beenthere = 0;
char *bol, *eol;
struct onas_rcvln rcv;
STATBUF sb;
int sockd = -1;
int (*recv_func)(struct onas_rcvln *, char **, char **, int64_t) = NULL;
sockd = onas_get_sockd();
onas_recvlninit(&rcv, curl, sockd);
if (rcv.sockd > 0) {
recv_func = &onas_fd_recvln;
} else {
recv_func = &onas_recvln;
}
switch (scantype) {
case MULTI:
case CONT:
case ALLMATCH:
if (!filename) {
logg(LOGG_INFO, "Filename cannot be NULL for MULTISCAN or CONTSCAN.\n");
if (ret_code) {
*ret_code = CL_ENULLARG;
}
infected = -1;
goto done;
}
len = strlen(filename) + strlen(scancmd[scantype]) + 3;
if (!(bol = malloc(len))) {
logg(LOGG_ERROR, "Cannot allocate a command buffer: %s\n", strerror(errno));
if (ret_code) {
*ret_code = CL_EMEM;
}
infected = -1;
goto done;
}
sprintf(bol, "z%s %s", scancmd[scantype], filename);
if (onas_sendln(curl, bol, len, timeout)) {
if (ret_code) {
*ret_code = CL_EWRITE;
}
free(bol);
infected = -1;
goto done;
}
free(bol);
break;
case STREAM:
/* NULL filename safe in send_stream() */
len = onas_send_stream(curl, filename, fd, timeout, maxstream);
break;
#ifdef HAVE_FD_PASSING
case FILDES:
/* NULL filename safe in send_fdpass() */
len = onas_fdpass(filename, fd, sockd);
break;
#endif
}
if (len <= 0) {
*printok = 0;
if (errors && len < 0) {
/* Ignore error if len == 0 to reduce verbosity from file open()
"errors" where the file has been deleted before we have a chance
to scan it. */
(*errors)++;
}
infected = len;
goto done;
}
while ((len = (*recv_func)(&rcv, &bol, &eol, timeout))) {
if (len == -1) {
if (ret_code) {
*ret_code = CL_EREAD;
}
infected = -1;
goto done;
}
beenthere = 1;
if (!filename) {
logg(LOGG_INFO, "%s\n", bol);
}
if (len > 7) {
char *colon = strrchr(bol, ':');
if (colon && colon[1] != ' ') {
char *br;
*colon = 0;
br = strrchr(bol, '(');
if (br) {
*br = 0;
}
colon = strrchr(bol, ':');
}
if (!colon) {
char *unkco = "UNKNOWN COMMAND";
if (!strncmp(bol, unkco, sizeof(unkco) - 1)) {
logg(LOGG_DEBUG, "clamd replied \"UNKNOWN COMMAND\". Command was %s\n",
(scantype < 0 || scantype > MAX_SCANTYPE) ? "unidentified" : scancmd[scantype]);
} else {
logg(LOGG_DEBUG, "Failed to parse reply: \"%s\"\n", bol);
}
if (ret_code) {
*ret_code = CL_EPARSE;
}
infected = -1;
goto done;
} else if (!memcmp(eol - 7, " FOUND", 6)) {
static char last_filename[PATH_MAX + 1] = {'\0'};
*(eol - 7) = 0;
*printok = 0;
if (scantype != ALLMATCH) {
infected++;
} else {
if (filename != NULL && strcmp(filename, last_filename)) {
infected++;
strncpy(last_filename, filename, PATH_MAX);
last_filename[PATH_MAX] = '\0';
}
}
if (filename) {
if (scantype >= STREAM) {
logg(LOGG_INFO, "%s%s FOUND\n", filename, colon);
if (action) {
action(filename);
}
} else {
logg(LOGG_INFO, "%s FOUND\n", bol);
*colon = '\0';
if (action) {
action(bol);
}
}
}
if (ret_code) {
*ret_code = CL_VIRUS;
}
} else if ((len > 32 && !memcmp(eol - 33, "No such file or directory. ERROR", 32)) ||
(len > 34 && !memcmp(eol - 35, "Can't open file or directory ERROR", 34))) {
if (errors) {
(*errors)++;
}
*printok = 0;
if (filename) {
(scantype >= STREAM) ? logg(LOGG_DEBUG, "%s%s\n", filename, colon) : logg(LOGG_DEBUG, "%s\n", bol);
}
if (ret_code) {
*ret_code = CL_ESTAT;
}
} else if ((len > 21 && !memcmp(eol - 22, " Access denied. ERROR", 21)) ||
(len > 23 && !memcmp(eol - 24, "Can't access file ERROR", 23)) ||
(len > 41 && !memcmp(eol - 42, " lstat() failed: Permission denied. ERROR", 41))) {
if (errors) {
(*errors)++;
}
*printok = 0;
if (filename) {
(scantype >= STREAM) ? logg(LOGG_INFO, "%s%s\n", filename, colon) : logg(LOGG_INFO, "%s\n", bol);
}
if (ret_code) {
*ret_code = CL_EACCES;
}
} else if (len > 6 && !memcmp(eol - 7, " ERROR", 6)) {
if (errors) {
(*errors)++;
}
*printok = 0;
if (filename) {
(scantype >= STREAM) ? logg(LOGG_INFO, "%s%s\n", filename, colon) : logg(LOGG_INFO, "%s\n", bol);
}
if (ret_code) {
*ret_code = CL_ERROR;
}
}
}
}
if (!beenthere) {
if (!filename) {
logg(LOGG_INFO, "STDIN: noreply from clamd\n.");
if (ret_code) {
*ret_code = CL_EACCES;
}
infected = -1;
goto done;
}
if (CLAMSTAT(filename, &sb) == -1) {
logg(LOGG_INFO, "%s: stat() failed with %s, clamd may not be responding\n",
filename, strerror(errno));
if (ret_code) {
*ret_code = CL_EACCES;
}
infected = -1;
goto done;
}
if (!S_ISDIR(sb.st_mode)) {
logg(LOGG_INFO, "%s: no reply from clamd\n", filename);
if (ret_code) {
*ret_code = CL_EACCES;
}
infected = -1;
goto done;
}
}
done:
if (sockd > 0) {
closesocket(sockd);
}
return infected;
}