1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) Tom Kistner <tom@duncanthrax.net> 2003-2014 */
8 /* Code for calling virus (malware) scanners. Called from acl.c. */
11 #ifdef WITH_CONTENT_SCAN
13 typedef enum {M_FPROTD, M_DRWEB, M_AVES, M_FSEC, M_KAVD, M_CMDL,
14 M_SOPHIE, M_CLAMD, M_SOCK, M_MKSD, M_AVAST} scanner_t;
15 typedef enum {MC_NONE, MC_TCP, MC_UNIX, MC_STRM} contype_t;
20 const uschar * options_default;
24 { M_FPROTD, US"f-protd", US"localhost 10200-10204", MC_TCP },
25 { M_DRWEB, US"drweb", US"/usr/local/drweb/run/drwebd.sock", MC_STRM },
26 { M_AVES, US"aveserver", US"/var/run/aveserver", MC_UNIX },
27 { M_FSEC, US"fsecure", US"/var/run/.fsav", MC_UNIX },
28 { M_KAVD, US"kavdaemon", US"/var/run/AvpCtl", MC_UNIX },
29 { M_CMDL, US"cmdline", NULL, MC_NONE },
30 { M_SOPHIE, US"sophie", US"/var/run/sophie", MC_UNIX },
31 { M_CLAMD, US"clamd", US"/tmp/clamd", MC_NONE },
32 { M_SOCK, US"sock", US"/tmp/malware.sock", MC_STRM },
33 { M_MKSD, US"mksd", NULL, MC_NONE },
34 { M_AVAST, US"avast", US"/var/run/avast/scan.sock", MC_STRM },
35 { -1, NULL, NULL, MC_NONE } /* end-marker */
38 /* The maximum number of clamd servers that are supported in the configuration */
39 #define MAX_CLAMD_SERVERS 32
40 #define MAX_CLAMD_SERVERS_S "32"
42 typedef struct clamd_address {
49 # define nelements(arr) (sizeof(arr) / sizeof(arr[0]))
53 #define MALWARE_TIMEOUT 120 /* default timeout, seconds */
56 #define DRWEBD_SCAN_CMD (1) /* scan file, buffer or diskfile */
57 #define DRWEBD_RETURN_VIRUSES (1<<0) /* ask daemon return to us viruses names from report */
58 #define DRWEBD_IS_MAIL (1<<19) /* say to daemon that format is "archive MAIL" */
60 #define DERR_READ_ERR (1<<0) /* read error */
61 #define DERR_NOMEMORY (1<<2) /* no memory */
62 #define DERR_TIMEOUT (1<<9) /* scan timeout has run out */
63 #define DERR_BAD_CALL (1<<15) /* wrong command */
66 static const uschar * malware_regex_default = US ".+";
67 static const pcre * malware_default_re = NULL;
69 static const uschar * drweb_re_str = US "infected\\swith\\s*(.+?)$";
70 static const pcre * drweb_re = NULL;
72 static const uschar * fsec_re_str = US "\\S{0,5}INFECTED\\t[^\\t]*\\t([^\\t]+)\\t\\S*$";
73 static const pcre * fsec_re = NULL;
75 static const uschar * kav_re_sus_str = US "suspicion:\\s*(.+?)\\s*$";
76 static const uschar * kav_re_inf_str = US "infected:\\s*(.+?)\\s*$";
77 static const pcre * kav_re_sus = NULL;
78 static const pcre * kav_re_inf = NULL;
80 static const uschar * ava_re_clean_str = US "(?!\\\\)\\t\\[\\+\\]";
81 static const uschar * ava_re_virus_str = US "(?!\\\\)\\t\\[L\\]\\d\\.\\d\\t\\d\\s(.*)";
82 static const pcre * ava_re_clean = NULL;
83 static const pcre * ava_re_virus = NULL;
87 /******************************************************************************/
89 /* Routine to check whether a system is big- or little-endian.
90 Ripped from http://www.faqs.org/faqs/graphics/fileformats-faq/part4/section-7.html
91 Needed for proper kavdaemon implementation. Sigh. */
92 #define BIG_MY_ENDIAN 0
93 #define LITTLE_MY_ENDIAN 1
94 static int test_byte_order(void);
98 short int word = 0x0001;
99 char *byte = (char *) &word;
100 return(byte[0] ? LITTLE_MY_ENDIAN : BIG_MY_ENDIAN);
103 BOOL malware_ok = FALSE;
105 /* Gross hacks for the -bmalware option; perhaps we should just create
106 the scan directory normally for that case, but look into rigging up the
107 needed header variables if not already set on the command-line? */
108 extern int spool_mbox_ok;
109 extern uschar spooled_message_id[17];
114 malware_errlog_defer(const uschar * str)
116 log_write(0, LOG_MAIN|LOG_PANIC, "malware acl condition: %s", str);
121 m_errlog_defer(struct scan * scanent, const uschar * str)
123 return malware_errlog_defer(string_sprintf("%s: %s", scanent->name, str));
126 m_errlog_defer_3(struct scan * scanent, const uschar * str,
129 (void) close(fd_to_close);
130 return m_errlog_defer(scanent, str);
133 /*************************************************/
135 /* Only used by the Clamav code, which is working from a list of servers and
136 uses the returned in_addr to get a second connection to the same system.
139 m_tcpsocket(const uschar * hostname, unsigned int port,
140 host_item * host, uschar ** errstr)
142 return ip_connectedsocket(SOCK_STREAM, hostname, port, port, 5, host, errstr);
146 m_sock_send(int sock, uschar * buf, int cnt, uschar ** errstr)
148 if (send(sock, buf, cnt, 0) < 0)
152 *errstr = string_sprintf("unable to send to socket (%s): %s",
160 m_pcre_compile(const uschar * re, uschar ** errstr)
162 const uschar * rerror;
166 cre = pcre_compile(CS re, PCRE_COPT, (const char **)&rerror, &roffset, NULL);
168 *errstr= string_sprintf("regular expression error in '%s': %s at offset %d",
169 re, rerror, roffset);
174 m_pcre_exec(const pcre * cre, uschar * text)
177 int i = pcre_exec(cre, NULL, CS text, Ustrlen(text), 0, 0,
178 ovector, nelements(ovector));
179 uschar * substr = NULL;
180 if (i >= 2) /* Got it */
181 pcre_get_substring(CS text, ovector, i, 1, (const char **) &substr);
186 m_pcre_nextinlist(const uschar ** list, int * sep,
187 char * listerr, uschar ** errstr)
189 const uschar * list_ele;
190 const pcre * cre = NULL;
192 if (!(list_ele = string_nextinlist(list, sep, NULL, 0)))
193 *errstr = US listerr;
195 cre = m_pcre_compile(CUS list_ele, errstr);
200 Simple though inefficient wrapper for reading a line. Drop CRs and the
201 trailing newline. Can return early on buffer full. Null-terminate.
202 Apply initial timeout if no data ready.
204 Return: number of chars - zero for an empty line
206 -2 on timeout or error
209 recv_line(int fd, uschar * buffer, int bsize, int tmo)
215 if (!fd_ready(fd, tmo-time(NULL)))
218 /*XXX tmo handling assumes we always get a whole line */
221 while ((rcv = read(fd, p, 1)) > 0)
224 if (p-buffer > bsize-2) break;
225 if (*p == '\n') break;
230 DEBUG(D_acl) debug_printf("Malware scan: read %s (%s)\n",
231 rcv==0 ? "EOF" : "error", strerror(errno));
232 return rcv==0 ? -1 : -2;
236 DEBUG(D_acl) debug_printf("Malware scan: read '%s'\n", buffer);
240 /* return TRUE iff size as requested */
242 recv_len(int sock, void * buf, int size, int tmo)
244 return fd_ready(sock, tmo-time(NULL))
245 ? recv(sock, buf, size, 0) == size
251 /* ============= private routines for the "mksd" scanner type ============== */
256 mksd_writev (int sock, struct iovec * iov, int iovcnt)
263 i = writev (sock, iov, iovcnt);
264 while (i < 0 && errno == EINTR);
267 (void) malware_errlog_defer(
268 US"unable to write to mksd UNIX socket (/var/run/mksd/socket)");
271 for (;;) /* check for short write */
272 if (i >= iov->iov_len)
282 iov->iov_base = CS iov->iov_base + i;
289 mksd_read_lines (int sock, uschar *av_buffer, int av_buffer_size, int tmo)
296 i = ip_recv(sock, av_buffer+offset, av_buffer_size-offset, tmo-time(NULL));
299 (void) malware_errlog_defer(US"unable to read from mksd UNIX socket (/var/run/mksd/socket)");
304 /* offset == av_buffer_size -> buffer full */
305 if (offset == av_buffer_size)
307 (void) malware_errlog_defer(US"malformed reply received from mksd");
310 } while (av_buffer[offset-1] != '\n');
312 av_buffer[offset] = '\0';
317 mksd_parse_line(struct scan * scanent, char * line)
328 if ((p = strchr (line, '\n')) != NULL)
330 return m_errlog_defer(scanent,
331 string_sprintf("scanner failed: %s", line));
334 if ((p = strchr (line, '\n')) != NULL)
339 && (p = strchr(line+4, ' ')) != NULL
344 malware_name = string_copy(US line+4);
348 return m_errlog_defer(scanent,
349 string_sprintf("malformed reply received: %s", line));
354 mksd_scan_packed(struct scan * scanent, int sock, const uschar * scan_filename,
358 const char *cmd = "MSQ\n";
359 uschar av_buffer[1024];
361 iov[0].iov_base = (void *) cmd;
363 iov[1].iov_base = (void *) scan_filename;
364 iov[1].iov_len = Ustrlen(scan_filename);
365 iov[2].iov_base = (void *) (cmd + 3);
368 if (mksd_writev (sock, iov, 3) < 0)
371 if (mksd_read_lines (sock, av_buffer, sizeof (av_buffer), tmo) < 0)
374 return mksd_parse_line (scanent, CS av_buffer);
379 clamd_option(clamd_address * cd, const uschar * optstr, int * subsep)
384 while ((s = string_nextinlist(&optstr, subsep, NULL, 0)))
386 if (Ustrncmp(s, "retry=", 6) == 0)
388 int sec = readconf_readtime((s += 6), '\0', FALSE);
398 /*************************************************
399 * Scan content for malware *
400 *************************************************/
402 /* This is an internal interface for scanning an email; the normal interface
403 is via malware(), or there's malware_in_file() used for testing/debugging.
406 malware_re match condition for "malware="
407 eml_filename the file holding the email to be scanned
408 timeout if nonzero, non-default timeoutl
409 faking whether or not we're faking this up for the -bmalware test
411 Returns: Exim message processing code (OK, FAIL, DEFER, ...)
412 where true means malware was found (condition applies)
415 malware_internal(const uschar * malware_re, const uschar * eml_filename,
416 int timeout, BOOL faking)
419 const uschar *av_scanner_work = av_scanner;
420 uschar *scanner_name;
421 unsigned long mbox_size;
425 struct scan * scanent;
426 const uschar * scanner_options;
430 /* make sure the eml mbox file is spooled up */
431 if (!(mbox_file = spool_mbox(&mbox_size, faking ? eml_filename : NULL)))
432 return malware_errlog_defer(US"error while creating mbox spool file");
434 /* none of our current scanners need the mbox
435 file as a stream, so we can close it right away */
436 (void)fclose(mbox_file);
439 return FAIL; /* empty means "don't match anything" */
441 /* parse 1st option */
442 if ( (strcmpic(malware_re, US"false") == 0) ||
443 (Ustrcmp(malware_re,"0") == 0) )
444 return FAIL; /* explicitly no matching */
446 /* special cases (match anything except empty) */
447 if ( strcmpic(malware_re,US"true") == 0
448 || Ustrcmp(malware_re,"*") == 0
449 || Ustrcmp(malware_re,"1") == 0
452 if ( !malware_default_re
453 && !(malware_default_re = m_pcre_compile(malware_regex_default, &errstr)))
454 return malware_errlog_defer(errstr);
455 malware_re = malware_regex_default;
456 re = malware_default_re;
459 /* compile the regex, see if it works */
460 else if (!(re = m_pcre_compile(malware_re, &errstr)))
461 return malware_errlog_defer(errstr);
463 /* Reset sep that is set by previous string_nextinlist() call */
466 /* if av_scanner starts with a dollar, expand it first */
467 if (*av_scanner == '$')
469 if (!(av_scanner_work = expand_string(av_scanner)))
470 return malware_errlog_defer(
471 string_sprintf("av_scanner starts with $, but expansion failed: %s",
472 expand_string_message));
475 debug_printf("Expanded av_scanner global: %s\n", av_scanner_work);
476 /* disable result caching in this case */
481 /* Do not scan twice (unless av_scanner is dynamic). */
484 /* find the scanner type from the av_scanner option */
485 if (!(scanner_name = string_nextinlist(&av_scanner_work, &sep, NULL, 0)))
486 return malware_errlog_defer(US"av_scanner configuration variable is empty");
487 if (!timeout) timeout = MALWARE_TIMEOUT;
488 tmo = time(NULL) + timeout;
490 for (scanent = m_scans; ; scanent++)
493 return malware_errlog_defer(string_sprintf("unknown scanner type '%s'",
495 if (strcmpic(scanner_name, US scanent->name) != 0)
497 if (!(scanner_options = string_nextinlist(&av_scanner_work, &sep, NULL, 0)))
498 scanner_options = scanent->options_default;
499 if (scanent->conn == MC_NONE)
501 switch(scanent->conn)
503 case MC_TCP: sock = ip_tcpsocket(scanner_options, &errstr, 5); break;
504 case MC_UNIX: sock = ip_unixsocket(scanner_options, &errstr); break;
505 case MC_STRM: sock = ip_streamsocket(scanner_options, &errstr, 5); break;
506 default: /* compiler quietening */ break;
509 return m_errlog_defer(scanent, errstr);
512 DEBUG(D_acl) debug_printf("Malware scan: %s tmo %s\n", scanner_name, readconf_printtime(timeout));
514 switch (scanent->scancode)
516 case M_FPROTD: /* "f-protd" scanner type -------------------------------- */
518 uschar *fp_scan_option;
519 unsigned int detected=0, par_count=0;
520 uschar * scanrequest;
521 uschar buf[32768], *strhelper, *strhelper2;
522 uschar * malware_name_internal = NULL;
525 scanrequest = string_sprintf("GET %s", eml_filename);
527 while ((fp_scan_option = string_nextinlist(&av_scanner_work, &sep,
530 scanrequest = string_sprintf("%s%s%s", scanrequest,
531 par_count ? "%20" : "?", fp_scan_option);
534 scanrequest = string_sprintf("%s HTTP/1.0\r\n\r\n", scanrequest);
535 DEBUG(D_acl) debug_printf("Malware scan: issuing %s: %s\n",
536 scanner_name, scanrequest);
538 /* send scan request */
539 if (m_sock_send(sock, scanrequest, Ustrlen(scanrequest)+1, &errstr) < 0)
540 return m_errlog_defer(scanent, errstr);
542 while ((len = recv_line(sock, buf, sizeof(buf), tmo)) >= 0)
545 if (Ustrstr(buf, US"<detected type=\"") != NULL)
547 else if (detected && (strhelper = Ustrstr(buf, US"<name>")))
549 if ((strhelper2 = Ustrstr(buf, US"</name>")) != NULL)
552 malware_name_internal = string_copy(strhelper+6);
555 else if (Ustrstr(buf, US"<summary code=\""))
557 malware_name = Ustrstr(buf, US"<summary code=\"11\">")
558 ? malware_name_internal : NULL;
570 case M_DRWEB: /* "drweb" scanner type ----------------------------------- */
571 /* v0.1 - added support for tcp sockets */
572 /* v0.0 - initial release -- support for unix sockets */
576 unsigned int fsize_uint;
577 uschar * tmpbuf, *drweb_fbuf;
578 int drweb_rc, drweb_cmd, drweb_flags = 0x0000, drweb_fd,
579 drweb_vnum, drweb_slen, drweb_fin = 0x0000;
581 /* prepare variables */
582 drweb_cmd = htonl(DRWEBD_SCAN_CMD);
583 drweb_flags = htonl(DRWEBD_RETURN_VIRUSES | DRWEBD_IS_MAIL);
585 if (*scanner_options != '/')
588 if ((drweb_fd = open(CCS eml_filename, O_RDONLY)) == -1)
589 return m_errlog_defer_3(scanent,
590 string_sprintf("can't open spool file %s: %s",
591 eml_filename, strerror(errno)),
594 if ((fsize = lseek(drweb_fd, 0, SEEK_END)) == -1)
597 (void)close(drweb_fd);
598 return m_errlog_defer_3(scanent,
599 string_sprintf("can't seek spool file %s: %s",
600 eml_filename, strerror(err)),
603 fsize_uint = (unsigned int) fsize;
604 if ((off_t)fsize_uint != fsize)
606 (void)close(drweb_fd);
607 return m_errlog_defer_3(scanent,
608 string_sprintf("seeking spool file %s, size overflow",
612 drweb_slen = htonl(fsize);
613 lseek(drweb_fd, 0, SEEK_SET);
615 DEBUG(D_acl) debug_printf("Malware scan: issuing %s remote scan [%s]\n",
616 scanner_name, scanner_options);
618 /* send scan request */
619 if ((send(sock, &drweb_cmd, sizeof(drweb_cmd), 0) < 0) ||
620 (send(sock, &drweb_flags, sizeof(drweb_flags), 0) < 0) ||
621 (send(sock, &drweb_fin, sizeof(drweb_fin), 0) < 0) ||
622 (send(sock, &drweb_slen, sizeof(drweb_slen), 0) < 0))
624 (void)close(drweb_fd);
625 return m_errlog_defer_3(scanent, string_sprintf(
626 "unable to send commands to socket (%s)", scanner_options),
630 if (!(drweb_fbuf = (uschar *) malloc (fsize_uint)))
632 (void)close(drweb_fd);
633 return m_errlog_defer_3(scanent,
634 string_sprintf("unable to allocate memory %u for file (%s)",
635 fsize_uint, eml_filename),
639 if ((result = read (drweb_fd, drweb_fbuf, fsize)) == -1)
642 (void)close(drweb_fd);
644 return m_errlog_defer_3(scanent,
645 string_sprintf("can't read spool file %s: %s",
646 eml_filename, strerror(err)),
649 (void)close(drweb_fd);
651 /* send file body to socket */
652 if (send(sock, drweb_fbuf, fsize, 0) < 0)
655 return m_errlog_defer_3(scanent, string_sprintf(
656 "unable to send file body to socket (%s)", scanner_options),
659 (void)close(drweb_fd);
663 drweb_slen = htonl(Ustrlen(eml_filename));
665 DEBUG(D_acl) debug_printf("Malware scan: issuing %s local scan [%s]\n",
666 scanner_name, scanner_options);
668 /* send scan request */
669 if ((send(sock, &drweb_cmd, sizeof(drweb_cmd), 0) < 0) ||
670 (send(sock, &drweb_flags, sizeof(drweb_flags), 0) < 0) ||
671 (send(sock, &drweb_slen, sizeof(drweb_slen), 0) < 0) ||
672 (send(sock, eml_filename, Ustrlen(eml_filename), 0) < 0) ||
673 (send(sock, &drweb_fin, sizeof(drweb_fin), 0) < 0))
674 return m_errlog_defer_3(scanent, string_sprintf(
675 "unable to send commands to socket (%s)", scanner_options),
679 /* wait for result */
680 if (!recv_len(sock, &drweb_rc, sizeof(drweb_rc), tmo))
681 return m_errlog_defer_3(scanent,
682 US"unable to read return code", sock);
683 drweb_rc = ntohl(drweb_rc);
685 if (!recv_len(sock, &drweb_vnum, sizeof(drweb_vnum), tmo))
686 return m_errlog_defer_3(scanent,
687 US"unable to read the number of viruses", sock);
688 drweb_vnum = ntohl(drweb_vnum);
690 /* "virus(es) found" if virus number is > 0 */
695 /* setup default virus name */
696 malware_name = US"unknown";
698 /* set up match regex */
700 drweb_re = m_pcre_compile(drweb_re_str, &errstr);
702 /* read and concatenate virus names into one string */
703 for (i = 0; i < drweb_vnum; i++)
705 int size = 0, off = 0, ovector[10*3];
706 /* read the size of report */
707 if (!recv_len(sock, &drweb_slen, sizeof(drweb_slen), tmo))
708 return m_errlog_defer_3(scanent,
709 US"cannot read report size", sock);
710 drweb_slen = ntohl(drweb_slen);
711 tmpbuf = store_get(drweb_slen);
713 /* read report body */
714 if (!recv_len(sock, tmpbuf, drweb_slen, tmo))
715 return m_errlog_defer_3(scanent,
716 US"cannot read report string", sock);
717 tmpbuf[drweb_slen] = '\0';
719 /* try matcher on the line, grab substring */
720 result = pcre_exec(drweb_re, NULL, CS tmpbuf, Ustrlen(tmpbuf), 0, 0,
721 ovector, nelements(ovector));
724 const char * pre_malware_nb;
726 pcre_get_substring(CS tmpbuf, ovector, result, 1, &pre_malware_nb);
728 if (i==0) /* the first name we just copy to malware_name */
729 malware_name = string_append(NULL, &size, &off,
732 else /* concatenate each new virus name to previous */
733 malware_name = string_append(malware_name, &size, &off,
734 2, "/", pre_malware_nb);
736 pcre_free_substring(pre_malware_nb);
742 const char *drweb_s = NULL;
744 if (drweb_rc & DERR_READ_ERR) drweb_s = "read error";
745 if (drweb_rc & DERR_NOMEMORY) drweb_s = "no memory";
746 if (drweb_rc & DERR_TIMEOUT) drweb_s = "timeout";
747 if (drweb_rc & DERR_BAD_CALL) drweb_s = "wrong command";
748 /* retcodes DERR_SYMLINK, DERR_NO_REGFILE, DERR_SKIPPED.
749 * DERR_TOO_BIG, DERR_TOO_COMPRESSED, DERR_SPAM,
750 * DERR_CRC_ERROR, DERR_READSOCKET, DERR_WRITE_ERR
751 * and others are ignored */
753 return m_errlog_defer_3(scanent,
754 string_sprintf("drweb daemon retcode 0x%x (%s)", drweb_rc, drweb_s),
763 case M_AVES: /* "aveserver" scanner type -------------------------------- */
768 /* read aveserver's greeting and see if it is ready (2xx greeting) */
770 recv_line(sock, buf, sizeof(buf), tmo);
772 if (buf[0] != '2') /* aveserver is having problems */
773 return m_errlog_defer_3(scanent,
774 string_sprintf("unavailable (Responded: %s).",
775 ((buf[0] != 0) ? buf : (uschar *)"nothing") ),
778 /* prepare our command */
779 (void)string_format(buf, sizeof(buf), "SCAN bPQRSTUW %s\r\n",
783 DEBUG(D_acl) debug_printf("Malware scan: issuing %s %s\n",
785 if (m_sock_send(sock, buf, Ustrlen(buf), &errstr) < 0)
786 return m_errlog_defer(scanent, errstr);
790 /* read response lines, find malware name and final response */
791 while (recv_line(sock, buf, sizeof(buf), tmo) > 0)
795 if (buf[0] == '5') /* aveserver is having problems */
797 result = m_errlog_defer(scanent,
798 string_sprintf("unable to scan file %s (Responded: %s).",
802 if (Ustrncmp(buf,"322",3) == 0)
804 uschar *p = Ustrchr(&buf[4], ' ');
806 malware_name = string_copy(&buf[4]);
810 if (m_sock_send(sock, US"quit\r\n", 6, &errstr) < 0)
811 return m_errlog_defer(scanent, errstr);
813 /* read aveserver's greeting and see if it is ready (2xx greeting) */
815 recv_line(sock, buf, sizeof(buf), tmo);
817 if (buf[0] != '2') /* aveserver is having problems */
818 return m_errlog_defer_3(scanent,
819 string_sprintf("unable to quit dialogue (Responded: %s).",
820 ((buf[0] != 0) ? buf : (uschar *)"nothing") ),
831 case M_FSEC: /* "fsecure" scanner type ---------------------------------- */
835 uschar av_buffer[1024];
836 static uschar *cmdopt[] = { US"CONFIGURE\tARCHIVE\t1\n",
837 US"CONFIGURE\tTIMEOUT\t0\n",
838 US"CONFIGURE\tMAXARCH\t5\n",
839 US"CONFIGURE\tMIME\t1\n" };
843 DEBUG(D_acl) debug_printf("Malware scan: issuing %s scan [%s]\n",
844 scanner_name, scanner_options);
846 memset(av_buffer, 0, sizeof(av_buffer));
847 for (i = 0; i != nelements(cmdopt); i++)
850 if (m_sock_send(sock, cmdopt[i], Ustrlen(cmdopt[i]), &errstr) < 0)
851 return m_errlog_defer(scanent, errstr);
853 bread = ip_recv(sock, av_buffer, sizeof(av_buffer), tmo-time(NULL));
854 if (bread > 0) av_buffer[bread]='\0';
856 return m_errlog_defer_3(scanent,
857 string_sprintf("unable to read answer %d (%s)", i, strerror(errno)),
859 for (j = 0; j < bread; j++)
860 if (av_buffer[j] == '\r' || av_buffer[j] == '\n')
864 /* pass the mailfile to fsecure */
865 file_name = string_sprintf("SCAN\t%s\n", eml_filename);
867 if (m_sock_send(sock, file_name, Ustrlen(file_name), &errstr) < 0)
868 return m_errlog_defer(scanent, errstr);
871 /* todo also SUSPICION\t */
873 fsec_re = m_pcre_compile(fsec_re_str, &errstr);
875 /* read report, linewise. Apply a timeout as the Fsecure daemon
876 sometimes wants an answer to "PING" but they won't tell us what */
878 uschar * p = av_buffer;
884 i = av_buffer+sizeof(av_buffer)-p;
885 if ((bread= ip_recv(sock, p, i-1, tmo-time(NULL))) < 0)
886 return m_errlog_defer_3(scanent,
887 string_sprintf("unable to read result (%s)", strerror(errno)),
890 for (p[bread] = '\0'; q = strchr(p, '\n'); p = q+1)
894 /* Really search for virus again? */
896 /* try matcher on the line, grab substring */
897 malware_name = m_pcre_exec(fsec_re, p);
899 if (Ustrstr(p, "OK\tScan ok."))
903 /* copy down the trailing partial line then read another chunk */
904 i = av_buffer+sizeof(av_buffer)-p;
905 memmove(av_buffer, p, i);
914 case M_KAVD: /* "kavdaemon" scanner type -------------------------------- */
918 uschar * scanrequest;
920 unsigned long kav_reportlen, bread;
924 /* get current date and time, build scan request */
926 /* pdp note: before the eml_filename parameter, this scanned the
927 directory; not finding documentation, so we'll strip off the directory.
928 The side-effect is that the test framework scanning may end up in
929 scanning more than was requested, but for the normal interface, this is
932 strftime(CS tmpbuf, sizeof(tmpbuf), "%d %b %H:%M:%S", localtime(&t));
933 scanrequest = string_sprintf("<0>%s:%s", CS tmpbuf, eml_filename);
934 p = Ustrrchr(scanrequest, '/');
938 DEBUG(D_acl) debug_printf("Malware scan: issuing %s scan [%s]\n",
939 scanner_name, scanner_options);
941 /* send scan request */
942 if (m_sock_send(sock, scanrequest, Ustrlen(scanrequest)+1, &errstr) < 0)
943 return m_errlog_defer(scanent, errstr);
945 /* wait for result */
946 if (!recv_len(sock, tmpbuf, 2, tmo))
947 return m_errlog_defer_3(scanent,
948 US"unable to read 2 bytes from socket.", sock);
950 /* get errorcode from one nibble */
951 kav_rc = tmpbuf[ test_byte_order()==LITTLE_MY_ENDIAN ? 0 : 1 ] & 0x0F;
954 case 5: case 6: /* improper kavdaemon configuration */
955 return m_errlog_defer_3(scanent,
956 US"please reconfigure kavdaemon to NOT disinfect or remove infected files.",
959 return m_errlog_defer_3(scanent,
960 US"reported 'scanning not completed' (code 1).", sock);
962 return m_errlog_defer_3(scanent,
963 US"reported 'kavdaemon damaged' (code 7).", sock);
966 /* code 8 is not handled, since it is ambigous. It appears mostly on
967 bounces where part of a file has been cut off */
969 /* "virus found" return codes (2-4) */
970 if (kav_rc > 1 && kav_rc < 5)
974 /* setup default virus name */
975 malware_name = US"unknown";
977 report_flag = tmpbuf[ test_byte_order() == LITTLE_MY_ENDIAN ? 1 : 0 ];
979 /* read the report, if available */
980 if (report_flag == 1)
982 /* read report size */
983 if (!recv_len(sock, &kav_reportlen, 4, tmo))
984 return m_errlog_defer_3(scanent,
985 US"cannot read report size", sock);
987 /* it's possible that avp returns av_buffer[1] == 1 but the
988 reportsize is 0 (!?) */
989 if (kav_reportlen > 0)
991 /* set up match regex, depends on retcode */
994 if (!kav_re_sus) kav_re_sus = m_pcre_compile(kav_re_sus_str, &errstr);
999 if (!kav_re_inf) kav_re_inf = m_pcre_compile(kav_re_inf_str, &errstr);
1000 kav_re = kav_re_inf;
1003 /* read report, linewise */
1004 while (kav_reportlen > 0)
1006 if ((bread = recv_line(sock, tmpbuf, sizeof(tmpbuf), tmo)) < 0)
1008 kav_reportlen -= bread+1;
1010 /* try matcher on the line, grab substring */
1011 if ((malware_name = m_pcre_exec(kav_re, tmpbuf)))
1017 else /* no virus found */
1018 malware_name = NULL;
1023 case M_CMDL: /* "cmdline" scanner type ---------------------------------- */
1025 const uschar *cmdline_scanner = scanner_options;
1026 const pcre *cmdline_trigger_re;
1027 const pcre *cmdline_regex_re;
1029 uschar * commandline;
1030 void (*eximsigchld)(int);
1031 void (*eximsigpipe)(int);
1032 FILE *scanner_out = NULL;
1034 FILE *scanner_record = NULL;
1035 uschar linebuffer[32767];
1040 if (!cmdline_scanner)
1041 return m_errlog_defer(scanent, errstr);
1043 /* find scanner output trigger */
1044 cmdline_trigger_re = m_pcre_nextinlist(&av_scanner_work, &sep,
1045 "missing trigger specification", &errstr);
1046 if (!cmdline_trigger_re)
1047 return m_errlog_defer(scanent, errstr);
1049 /* find scanner name regex */
1050 cmdline_regex_re = m_pcre_nextinlist(&av_scanner_work, &sep,
1051 "missing virus name regex specification", &errstr);
1052 if (!cmdline_regex_re)
1053 return m_errlog_defer(scanent, errstr);
1055 /* prepare scanner call; despite the naming, file_name holds a directory
1056 name which is documented as the value given to %s. */
1058 file_name = string_copy(eml_filename);
1059 p = Ustrrchr(file_name, '/');
1062 commandline = string_sprintf(CS cmdline_scanner, file_name);
1064 /* redirect STDERR too */
1065 commandline = string_sprintf("%s 2>&1", commandline);
1067 DEBUG(D_acl) debug_printf("Malware scan: issuing %s scan [%s]\n",
1068 scanner_name, commandline);
1070 /* store exims signal handlers */
1071 eximsigchld = signal(SIGCHLD,SIG_DFL);
1072 eximsigpipe = signal(SIGPIPE,SIG_DFL);
1074 if (!(scanner_out = popen(CS commandline,"r")))
1077 signal(SIGCHLD,eximsigchld); signal(SIGPIPE,eximsigpipe);
1078 return m_errlog_defer(scanent,
1079 string_sprintf("call (%s) failed: %s.", commandline, strerror(err)));
1081 scanner_fd = fileno(scanner_out);
1083 file_name = string_sprintf("%s/scan/%s/%s_scanner_output",
1084 spool_directory, message_id, message_id);
1086 if (!(scanner_record = modefopen(file_name, "wb", SPOOL_MODE)))
1089 (void) pclose(scanner_out);
1090 signal(SIGCHLD,eximsigchld); signal(SIGPIPE,eximsigpipe);
1091 return m_errlog_defer(scanent, string_sprintf(
1092 "opening scanner output file (%s) failed: %s.",
1093 file_name, strerror(err)));
1096 /* look for trigger while recording output */
1097 while ((rcnt = recv_line(scanner_fd, linebuffer,
1098 sizeof(linebuffer), tmo)))
1106 (void) pclose(scanner_out);
1107 signal(SIGCHLD,eximsigchld); signal(SIGPIPE,eximsigpipe);
1108 return m_errlog_defer(scanent, string_sprintf(
1109 "unable to read from scanner (%s): %s",
1110 commandline, strerror(err)));
1113 if (Ustrlen(linebuffer) > fwrite(linebuffer, 1, Ustrlen(linebuffer), scanner_record))
1116 (void) pclose(scanner_out);
1117 signal(SIGCHLD,eximsigchld); signal(SIGPIPE,eximsigpipe);
1118 return m_errlog_defer(scanent, string_sprintf(
1119 "short write on scanner output file (%s).", file_name));
1121 putc('\n', scanner_record);
1122 /* try trigger match */
1124 && regex_match_and_setup(cmdline_trigger_re, linebuffer, 0, -1)
1129 (void)fclose(scanner_record);
1130 sep = pclose(scanner_out);
1131 signal(SIGCHLD,eximsigchld); signal(SIGPIPE,eximsigpipe);
1133 return m_errlog_defer(scanent,
1135 ? string_sprintf("running scanner failed: %s", strerror(sep))
1136 : string_sprintf("scanner returned error code: %d", sep));
1141 /* setup default virus name */
1142 malware_name = US"unknown";
1144 /* re-open the scanner output file, look for name match */
1145 scanner_record = fopen(CS file_name, "rb");
1146 while (fgets(CS linebuffer, sizeof(linebuffer), scanner_record))
1149 if ((s = m_pcre_exec(cmdline_regex_re, linebuffer)))
1152 (void)fclose(scanner_record);
1154 else /* no virus found */
1155 malware_name = NULL;
1159 case M_SOPHIE: /* "sophie" scanner type --------------------------------- */
1164 uschar av_buffer[1024];
1166 /* pass the scan directory to sophie */
1167 file_name = string_copy(eml_filename);
1168 if ((p = Ustrrchr(file_name, '/')))
1171 DEBUG(D_acl) debug_printf("Malware scan: issuing %s scan [%s]\n",
1172 scanner_name, scanner_options);
1174 if ( write(sock, file_name, Ustrlen(file_name)) < 0
1175 || write(sock, "\n", 1) != 1
1177 return m_errlog_defer_3(scanent,
1178 string_sprintf("unable to write to UNIX socket (%s)", scanner_options),
1181 /* wait for result */
1182 memset(av_buffer, 0, sizeof(av_buffer));
1183 if ((bread = ip_recv(sock, av_buffer, sizeof(av_buffer), tmo-time(NULL))) <= 0)
1184 return m_errlog_defer_3(scanent,
1185 string_sprintf("unable to read from UNIX socket (%s)", scanner_options),
1189 if (av_buffer[0] == '1') {
1190 uschar * s = Ustrchr(av_buffer, '\n');
1193 malware_name = string_copy(&av_buffer[2]);
1195 else if (!strncmp(CS av_buffer, "-1", 2))
1196 return m_errlog_defer_3(scanent, US"scanner reported error", sock);
1197 else /* all ok, no virus */
1198 malware_name = NULL;
1203 case M_CLAMD: /* "clamd" scanner type ----------------------------------- */
1205 /* This code was originally contributed by David Saez */
1206 /* There are three scanning methods available to us:
1207 * (1) Use the SCAN command, pointing to a file in the filesystem
1208 * (2) Use the STREAM command, send the data on a separate port
1209 * (3) Use the zINSTREAM command, send the data inline
1210 * The zINSTREAM command was introduced with ClamAV 0.95, which marked
1211 * STREAM deprecated; see: http://wiki.clamav.net/bin/view/Main/UpgradeNotes095
1212 * In Exim, we use SCAN if using a Unix-domain socket or explicitly told that
1213 * the TCP-connected daemon is actually local; otherwise we use zINSTREAM unless
1214 * WITH_OLD_CLAMAV_STREAM is defined.
1215 * See Exim bug 926 for details. */
1217 uschar *p, *vname, *result_tag, *response_end;
1220 uschar av_buffer[1024];
1221 uschar *hostname = US"";
1223 uschar *clamav_fbuf;
1224 int clam_fd, result;
1226 unsigned int fsize_uint;
1227 BOOL use_scan_command = FALSE;
1228 clamd_address * cv[MAX_CLAMD_SERVERS];
1229 int num_servers = 0;
1230 #ifdef WITH_OLD_CLAMAV_STREAM
1232 uschar av_buffer2[1024];
1235 uint32_t send_size, send_final_zeroblock;
1238 /*XXX if unixdomain socket, only one server supported. Needs fixing;
1239 there's no reason we should not mix local and remote servers */
1241 if (*scanner_options == '/')
1244 const uschar * sublist;
1247 /* Local file; so we def want to use_scan_command and don't want to try
1248 * passing IP/port combinations */
1249 use_scan_command = TRUE;
1250 cd = (clamd_address *) store_get(sizeof(clamd_address));
1252 /* extract socket-path part */
1253 sublist = scanner_options;
1254 cd->hostspec = string_nextinlist(&sublist, &subsep, NULL, 0);
1257 if (clamd_option(cd, sublist, &subsep) != OK)
1258 return m_errlog_defer(scanent,
1259 string_sprintf("bad option '%s'", scanner_options));
1264 /* Go through the rest of the list of host/port and construct an array
1265 * of servers to try. The first one is the bit we just passed from
1266 * scanner_options so process that first and then scan the remainder of
1267 * the address buffer */
1271 const uschar * sublist;
1275 /* The 'local' option means use the SCAN command over the network
1276 * socket (ie common file storage in use) */
1277 /*XXX we could accept this also as a local option? */
1278 if (strcmpic(scanner_options, US"local") == 0)
1280 use_scan_command = TRUE;
1284 cd = (clamd_address *) store_get(sizeof(clamd_address));
1286 /* extract host and port part */
1287 sublist = scanner_options;
1288 if (!(cd->hostspec = string_nextinlist(&sublist, &subsep, NULL, 0)))
1290 (void) m_errlog_defer(scanent,
1291 string_sprintf("missing address: '%s'", scanner_options));
1294 if (!(s = string_nextinlist(&sublist, &subsep, NULL, 0)))
1296 (void) m_errlog_defer(scanent,
1297 string_sprintf("missing port: '%s'", scanner_options));
1300 cd->tcp_port = atoi(s);
1303 /*XXX should these options be common over scanner types? */
1304 if (clamd_option(cd, sublist, &subsep) != OK)
1306 return m_errlog_defer(scanent,
1307 string_sprintf("bad option '%s'", scanner_options));
1311 cv[num_servers++] = cd;
1312 if (num_servers >= MAX_CLAMD_SERVERS)
1314 (void) m_errlog_defer(scanent,
1315 US"More than " MAX_CLAMD_SERVERS_S " clamd servers "
1316 "specified; only using the first " MAX_CLAMD_SERVERS_S );
1319 } while ((scanner_options = string_nextinlist(&av_scanner_work, &sep,
1322 /* check if we have at least one server */
1324 return m_errlog_defer(scanent,
1325 US"no useable server addresses in malware configuration option.");
1328 /* See the discussion of response formats below to see why we really
1329 don't like colons in filenames when passing filenames to ClamAV. */
1330 if (use_scan_command && Ustrchr(eml_filename, ':'))
1331 return m_errlog_defer(scanent,
1332 string_sprintf("local/SCAN mode incompatible with" \
1333 " : in path to email filename [%s]", eml_filename));
1335 /* We have some network servers specified */
1338 /* Confirmed in ClamAV source (0.95.3) that the TCPAddr option of clamd
1339 * only supports AF_INET, but we should probably be looking to the
1340 * future and rewriting this to be protocol-independent anyway. */
1342 while (num_servers > 0)
1344 int i = random_number( num_servers );
1345 clamd_address * cd = cv[i];
1347 DEBUG(D_acl) debug_printf("trying server name %s, port %u\n",
1348 cd->hostspec, cd->tcp_port);
1350 /* Lookup the host. This is to ensure that we connect to the same IP
1351 * on both connections (as one host could resolve to multiple ips) */
1354 sock= m_tcpsocket(cd->hostspec, cd->tcp_port, &connhost, &errstr);
1357 /* Connection successfully established with a server */
1358 hostname = cd->hostspec;
1361 if (cd->retry <= 0) break;
1362 while (cd->retry > 0) cd->retry = sleep(cd->retry);
1367 log_write(0, LOG_MAIN, "malware acl condition: %s: %s",
1368 scanent->name, errstr);
1370 /* Remove the server from the list. XXX We should free the memory */
1372 for (; i < num_servers; i++)
1376 if (num_servers == 0)
1377 return m_errlog_defer(scanent, US"all servers failed");
1382 if ((sock = ip_unixsocket(cv[0]->hostspec, &errstr)) >= 0)
1384 hostname = cv[0]->hostspec;
1387 if (cv[0]->retry <= 0)
1388 return m_errlog_defer(scanent, errstr);
1389 while (cv[0]->retry > 0) cv[0]->retry = sleep(cv[0]->retry);
1392 /* have socket in variable "sock"; command to use is semi-independent of
1393 * the socket protocol. We use SCAN if is local (either Unix/local
1394 * domain socket, or explicitly told local) else we stream the data.
1395 * How we stream the data depends upon how we were built. */
1397 if (!use_scan_command)
1399 #ifdef WITH_OLD_CLAMAV_STREAM
1400 /* "STREAM\n" command, get back a "PORT <N>\n" response, send data to
1401 * that port on a second connection; then in the scan-method-neutral
1402 * part, read the response back on the original connection. */
1404 DEBUG(D_acl) debug_printf(
1405 "Malware scan: issuing %s old-style remote scan (PORT)\n",
1408 /* Pass the string to ClamAV (7 = "STREAM\n") */
1409 if (m_sock_send(sock, US"STREAM\n", 7, &errstr) < 0)
1410 return m_errlog_defer(scanent, errstr);
1412 memset(av_buffer2, 0, sizeof(av_buffer2));
1413 bread = ip_recv(sock, av_buffer2, sizeof(av_buffer2), tmo-time(NULL));
1416 return m_errlog_defer_3(scanent,
1417 string_sprintf("unable to read PORT from socket (%s)",
1421 if (bread == sizeof(av_buffer2))
1422 return m_errlog_defer_3(scanent, "buffer too small", sock);
1425 return m_errlog_defer_3(scanent, "ClamAV returned null", sock);
1427 av_buffer2[bread] = '\0';
1428 if( sscanf(CS av_buffer2, "PORT %u\n", &port) != 1 )
1429 return m_errlog_defer_3(scanent,
1430 string_sprintf("Expected port information from clamd, got '%s'",
1434 sockData = m_tcpsocket(connhost.address, port, NULL, &errstr);
1436 return m_errlog_defer_3(scanent, errstr, sock);
1438 # define CLOSE_SOCKDATA (void)close(sockData)
1439 #else /* WITH_OLD_CLAMAV_STREAM not defined */
1440 /* New protocol: "zINSTREAM\n" followed by a sequence of <length><data>
1441 chunks, <n> a 4-byte number (network order), terminated by a zero-length
1444 DEBUG(D_acl) debug_printf(
1445 "Malware scan: issuing %s new-style remote scan (zINSTREAM)\n",
1448 /* Pass the string to ClamAV (10 = "zINSTREAM\0") */
1449 if (send(sock, "zINSTREAM", 10, 0) < 0)
1450 return m_errlog_defer_3(scanent,
1451 string_sprintf("unable to send zINSTREAM to socket (%s)",
1455 # define CLOSE_SOCKDATA /**/
1458 /* calc file size */
1459 if ((clam_fd = open(CS eml_filename, O_RDONLY)) < 0)
1463 return m_errlog_defer_3(scanent,
1464 string_sprintf("can't open spool file %s: %s",
1465 eml_filename, strerror(err)),
1468 if ((fsize = lseek(clam_fd, 0, SEEK_END)) < 0)
1471 CLOSE_SOCKDATA; (void)close(clam_fd);
1472 return m_errlog_defer_3(scanent,
1473 string_sprintf("can't seek spool file %s: %s",
1474 eml_filename, strerror(err)),
1477 fsize_uint = (unsigned int) fsize;
1478 if ((off_t)fsize_uint != fsize)
1480 CLOSE_SOCKDATA; (void)close(clam_fd);
1481 return m_errlog_defer_3(scanent,
1482 string_sprintf("seeking spool file %s, size overflow",
1486 lseek(clam_fd, 0, SEEK_SET);
1488 if (!(clamav_fbuf = (uschar *) malloc (fsize_uint)))
1490 CLOSE_SOCKDATA; (void)close(clam_fd);
1491 return m_errlog_defer_3(scanent,
1492 string_sprintf("unable to allocate memory %u for file (%s)",
1493 fsize_uint, eml_filename),
1497 if ((result = read(clam_fd, clamav_fbuf, fsize_uint)) < 0)
1500 free(clamav_fbuf); CLOSE_SOCKDATA; (void)close(clam_fd);
1501 return m_errlog_defer_3(scanent,
1502 string_sprintf("can't read spool file %s: %s",
1503 eml_filename, strerror(err)),
1506 (void)close(clam_fd);
1508 /* send file body to socket */
1509 #ifdef WITH_OLD_CLAMAV_STREAM
1510 if (send(sockData, clamav_fbuf, fsize_uint, 0) < 0)
1512 free(clamav_fbuf); CLOSE_SOCKDATA;
1513 return m_errlog_defer_3(scanent,
1514 string_sprintf("unable to send file body to socket (%s:%u)",
1519 send_size = htonl(fsize_uint);
1520 send_final_zeroblock = 0;
1521 if ((send(sock, &send_size, sizeof(send_size), 0) < 0) ||
1522 (send(sock, clamav_fbuf, fsize_uint, 0) < 0) ||
1523 (send(sock, &send_final_zeroblock, sizeof(send_final_zeroblock), 0) < 0))
1526 return m_errlog_defer_3(scanent,
1527 string_sprintf("unable to send file body to socket (%s)", hostname),
1535 #undef CLOSE_SOCKDATA
1538 { /* use scan command */
1539 /* Send a SCAN command pointing to a filename; then in the then in the
1540 * scan-method-neutral part, read the response back */
1542 /* ================================================================= */
1544 /* Prior to the reworking post-Exim-4.72, this scanned a directory,
1545 which dates to when ClamAV needed us to break apart the email into the
1546 MIME parts (eg, with the now deprecated demime condition coming first).
1547 Some time back, ClamAV gained the ability to deconstruct the emails, so
1548 doing this would actually have resulted in the mail attachments being
1549 scanned twice, in the broken out files and from the original .eml.
1550 Since ClamAV now handles emails (and has for quite some time) we can
1551 just use the email file itself. */
1552 /* Pass the string to ClamAV (7 = "SCAN \n" + \0) */
1553 file_name = string_sprintf("SCAN %s\n", eml_filename);
1555 DEBUG(D_acl) debug_printf(
1556 "Malware scan: issuing %s local-path scan [%s]\n",
1557 scanner_name, scanner_options);
1559 if (send(sock, file_name, Ustrlen(file_name), 0) < 0)
1560 return m_errlog_defer_3(scanent,
1561 string_sprintf("unable to write to socket (%s)", strerror(errno)),
1564 /* Do not shut down the socket for writing; a user report noted that
1565 * clamd 0.70 does not react well to this. */
1567 /* Commands have been sent, no matter which scan method or connection
1568 * type we're using; now just read the result, independent of method. */
1570 /* Read the result */
1571 memset(av_buffer, 0, sizeof(av_buffer));
1572 bread = ip_recv(sock, av_buffer, sizeof(av_buffer), tmo-time(NULL));
1577 return m_errlog_defer(scanent,
1578 string_sprintf("unable to read from socket (%s)",
1579 errno == 0 ? "EOF" : strerror(errno)));
1581 if (bread == sizeof(av_buffer))
1582 return m_errlog_defer(scanent, US"buffer too small");
1583 /* We're now assured of a NULL at the end of av_buffer */
1585 /* Check the result. ClamAV returns one of two result formats.
1586 In the basic mode, the response is of the form:
1587 infected: -> "<filename>: <virusname> FOUND"
1588 not-infected: -> "<filename>: OK"
1589 error: -> "<filename>: <errcode> ERROR
1590 If the ExtendedDetectionInfo option has been turned on, then we get:
1591 "<filename>: <virusname>(<virushash>:<virussize>) FOUND"
1592 for the infected case. Compare:
1593 /tmp/eicar.com: Eicar-Test-Signature FOUND
1594 /tmp/eicar.com: Eicar-Test-Signature(44d88612fea8a8f36de82e1278abb02f:68) FOUND
1596 In the streaming case, clamd uses the filename "stream" which you should
1597 be able to verify with { ktrace clamdscan --stream /tmp/eicar.com }. (The
1598 client app will replace "stream" with the original filename before returning
1599 results to stdout, but the trace shows the data).
1601 We will assume that the pathname passed to clamd from Exim does not contain
1602 a colon. We will have whined loudly above if the eml_filename does (and we're
1603 passing a filename to clamd). */
1606 return m_errlog_defer(scanent, US"ClamAV returned null");
1608 /* strip newline at the end (won't be present for zINSTREAM)
1609 (also any trailing whitespace, which shouldn't exist, but we depend upon
1610 this below, so double-check) */
1611 p = av_buffer + Ustrlen(av_buffer) - 1;
1612 if (*p == '\n') *p = '\0';
1614 DEBUG(D_acl) debug_printf("Malware response: %s\n", av_buffer);
1616 while (isspace(*--p) && (p > av_buffer))
1621 /* colon in returned output? */
1622 if((p = Ustrchr(av_buffer,':')) == NULL)
1623 return m_errlog_defer(scanent, string_sprintf(
1624 "ClamAV returned malformed result (missing colon): %s",
1627 /* strip filename */
1628 while (*p && isspace(*++p)) /**/;
1631 /* It would be bad to encounter a virus with "FOUND" in part of the name,
1632 but we should at least be resistant to it. */
1633 p = Ustrrchr(vname, ' ');
1634 result_tag = p ? p+1 : vname;
1636 if (Ustrcmp(result_tag, "FOUND") == 0)
1638 /* p should still be the whitespace before the result_tag */
1639 while (isspace(*p)) --p;
1641 /* Strip off the extended information too, which will be in parens
1642 after the virus name, with no intervening whitespace. */
1645 /* "(hash:size)", so previous '(' will do; if not found, we have
1646 a curious virus name, but not an error. */
1647 p = Ustrrchr(vname, '(');
1651 malware_name = string_copy(vname);
1652 DEBUG(D_acl) debug_printf("Malware found, name \"%s\"\n", malware_name);
1655 else if (Ustrcmp(result_tag, "ERROR") == 0)
1656 return m_errlog_defer(scanent,
1657 string_sprintf("ClamAV returned: %s", av_buffer));
1659 else if (Ustrcmp(result_tag, "OK") == 0)
1661 /* Everything should be OK */
1662 malware_name = NULL;
1663 DEBUG(D_acl) debug_printf("Malware not found\n");
1667 return m_errlog_defer(scanent,
1668 string_sprintf("unparseable response from ClamAV: {%s}", av_buffer));
1673 case M_SOCK: /* "sock" scanner type ------------------------------------- */
1674 /* This code was derived by Martin Poole from the clamd code contributed
1675 by David Saez and the cmdline code
1679 uschar * commandline;
1680 uschar av_buffer[1024];
1681 uschar * linebuffer;
1682 uschar * sockline_scanner;
1683 uschar sockline_scanner_default[] = "%s\n";
1684 const pcre *sockline_trig_re;
1685 const pcre *sockline_name_re;
1687 /* find scanner command line */
1688 if ((sockline_scanner = string_nextinlist(&av_scanner_work, &sep,
1690 { /* check for no expansions apart from one %s */
1691 uschar * s = Ustrchr(sockline_scanner, '%');
1693 if ((*s != 's' && *s != '%') || Ustrchr(s+1, '%'))
1694 return m_errlog_defer_3(scanent,
1695 US"unsafe sock scanner call spec", sock);
1698 sockline_scanner = sockline_scanner_default;
1700 /* find scanner output trigger */
1701 sockline_trig_re = m_pcre_nextinlist(&av_scanner_work, &sep,
1702 "missing trigger specification", &errstr);
1703 if (!sockline_trig_re)
1704 return m_errlog_defer_3(scanent, errstr, sock);
1706 /* find virus name regex */
1707 sockline_name_re = m_pcre_nextinlist(&av_scanner_work, &sep,
1708 "missing virus name regex specification", &errstr);
1709 if (!sockline_name_re)
1710 return m_errlog_defer_3(scanent, errstr, sock);
1712 /* prepare scanner call - security depends on expansions check above */
1713 commandline = string_sprintf("%s/scan/%s/%s.eml", spool_directory, message_id, message_id);
1714 commandline = string_sprintf( CS sockline_scanner, CS commandline);
1717 /* Pass the command string to the socket */
1718 if (m_sock_send(sock, commandline, Ustrlen(commandline), &errstr) < 0)
1719 return m_errlog_defer(scanent, errstr);
1721 /* Read the result */
1722 bread = ip_recv(sock, av_buffer, sizeof(av_buffer), tmo-time(NULL));
1725 return m_errlog_defer_3(scanent,
1726 string_sprintf("unable to read from socket (%s)", strerror(errno)),
1729 if (bread == sizeof(av_buffer))
1730 return m_errlog_defer_3(scanent, US"buffer too small", sock);
1731 av_buffer[bread] = '\0';
1732 linebuffer = string_copy(av_buffer);
1734 /* try trigger match */
1735 if (regex_match_and_setup(sockline_trig_re, linebuffer, 0, -1))
1737 if (!(malware_name = m_pcre_exec(sockline_name_re, av_buffer)))
1738 malware_name = US "unknown";
1740 else /* no virus found */
1741 malware_name = NULL;
1745 case M_MKSD: /* "mksd" scanner type ------------------------------------- */
1747 char *mksd_options_end;
1748 int mksd_maxproc = 1; /* default, if no option supplied */
1751 if (scanner_options)
1753 mksd_maxproc = (int)strtol(CS scanner_options, &mksd_options_end, 10);
1754 if ( *scanner_options == '\0'
1755 || *mksd_options_end != '\0'
1757 || mksd_maxproc > 32
1759 return m_errlog_defer(scanent,
1760 string_sprintf("invalid option '%s'", scanner_options));
1763 if((sock = ip_unixsocket(US "/var/run/mksd/socket", &errstr)) < 0)
1764 return m_errlog_defer(scanent, errstr);
1766 malware_name = NULL;
1768 DEBUG(D_acl) debug_printf("Malware scan: issuing %s scan\n", scanner_name);
1770 if ((retval = mksd_scan_packed(scanent, sock, eml_filename, tmo)) != OK)
1778 case M_AVAST: /* "avast" scanner type ----------------------------------- */
1782 uschar * scanrequest;
1783 enum {AVA_HELO, AVA_OPT, AVA_RSP, AVA_DONE} avast_stage;
1786 /* According to Martin Tuma @avast the protocol uses "escaped
1787 whitespace", that is, every embedded whitespace is backslash
1788 escaped, as well as backslash is protected by backslash.
1789 The returned lines contain the name of the scanned file, a tab
1793 [E] - some error occured
1794 Such marker follows the first non-escaped TAB. */
1795 if ( ( !ava_re_clean
1796 && !(ava_re_clean = m_pcre_compile(ava_re_clean_str, &errstr)))
1798 && !(ava_re_virus = m_pcre_compile(ava_re_virus_str, &errstr)))
1800 return malware_errlog_defer(errstr);
1802 /* wait for result */
1803 for (avast_stage = AVA_HELO;
1804 (nread = recv_line(sock, buf, sizeof(buf), tmo)) > 0;
1807 int slen = Ustrlen(buf);
1810 DEBUG(D_acl) debug_printf("got from avast: %s\n", buf);
1811 switch (avast_stage)
1814 if (Ustrncmp(buf, "220", 3) != 0)
1815 goto endloop; /* require a 220 */
1819 if (Ustrncmp(buf, "210", 3) == 0)
1820 break; /* ignore 210 responses */
1821 if (Ustrncmp(buf, "200", 3) != 0)
1822 goto endloop; /* require a 200 */
1827 /* Check for another option to send. Newline-terminate it. */
1828 if ((scanrequest = string_nextinlist(&av_scanner_work, &sep,
1831 scanrequest = string_sprintf("%s\n", scanrequest);
1832 avast_stage = AVA_OPT; /* just sent option */
1836 scanrequest = string_sprintf("SCAN %s/scan/%s\n",
1837 spool_directory, message_id);
1838 avast_stage = AVA_RSP; /* just sent command */
1841 /* send config-cmd or scan-request to socket */
1842 len = Ustrlen(scanrequest);
1843 if (send(sock, scanrequest, len, 0) < 0)
1845 scanrequest[len-1] = '\0';
1846 return m_errlog_defer_3(scanent, string_sprintf(
1847 "unable to send request '%s' to socket (%s): %s",
1848 scanrequest, scanner_options, strerror(errno)), sock);
1854 if (Ustrncmp(buf, "210", 3) == 0)
1855 break; /* ignore the "210 SCAN DATA" message */
1857 if (pcre_exec(ava_re_clean, NULL, CS buf, slen,
1858 0, 0, ovector, nelements(ovector)) > 0)
1861 if ((malware_name = m_pcre_exec(ava_re_virus, buf)))
1862 { /* remove backslash in front of [whitespace|backslash] */
1864 for (p = malware_name; *p; ++p)
1865 if (*p == '\\' && (isspace(p[1]) || p[1] == '\\'))
1866 for (p0 = p; *p0; ++p0) *p0 = p0[1];
1868 avast_stage = AVA_DONE;
1872 if (Ustrncmp(buf, "200 SCAN OK", 11) == 0)
1873 { /* we're done finally */
1874 if (send(sock, "QUIT\n", 5, 0) < 0) /* courtesy */
1875 return m_errlog_defer_3(scanent, string_sprintf(
1876 "unable to send quit request to socket (%s): %s",
1877 scanner_options, strerror(errno)),
1879 malware_name = NULL;
1880 avast_stage = AVA_DONE;
1884 /* here for any unexpected response from the scanner */
1895 case AVA_RSP: return m_errlog_defer_3(scanent,
1898 "invalid response from scanner: '%s'", buf)
1900 ? US"EOF from scanner"
1901 : US"timeout from scanner",
1907 } /* scanner type switch */
1910 (void) close (sock);
1911 malware_ok = TRUE; /* set "been here, done that" marker */
1914 /* match virus name against pattern (caseless ------->----------v) */
1915 if (malware_name && regex_match_and_setup(re, malware_name, 0, -1))
1917 DEBUG(D_acl) debug_printf(
1918 "Matched regex to malware [%s] [%s]\n", malware_re, malware_name);
1926 /*************************************************
1927 * Scan an email for malware *
1928 *************************************************/
1930 /* This is the normal interface for scanning an email, which doesn't need a
1931 filename; it's a wrapper around the malware_file function.
1934 malware_re match condition for "malware="
1935 timeout if nonzero, timeout in seconds
1937 Returns: Exim message processing code (OK, FAIL, DEFER, ...)
1938 where true means malware was found (condition applies)
1941 malware(const uschar * malware_re, int timeout)
1943 uschar * scan_filename;
1946 scan_filename = string_sprintf("%s/scan/%s/%s.eml",
1947 spool_directory, message_id, message_id);
1948 ret = malware_internal(malware_re, scan_filename, timeout, FALSE);
1949 if (ret == DEFER) av_failed = TRUE;
1955 /*************************************************
1956 * Scan a file for malware *
1957 *************************************************/
1959 /* This is a test wrapper for scanning an email, which is not used in
1960 normal processing. Scan any file, using the Exim scanning interface.
1961 This function tampers with various global variables so is unsafe to use
1962 in any other context.
1965 eml_filename a file holding the message to be scanned
1967 Returns: Exim message processing code (OK, FAIL, DEFER, ...)
1968 where true means malware was found (condition applies)
1971 malware_in_file(uschar *eml_filename)
1973 uschar message_id_buf[64];
1976 /* spool_mbox() assumes various parameters exist, when creating
1977 the relevant directory and the email within */
1978 (void) string_format(message_id_buf, sizeof(message_id_buf),
1979 "dummy-%d", vaguely_random_number(INT_MAX));
1980 message_id = message_id_buf;
1981 sender_address = US"malware-sender@example.net";
1983 recipients_list = NULL;
1984 receive_add_recipient(US"malware-victim@example.net", -1);
1985 enable_dollar_recipients = TRUE;
1987 ret = malware_internal(US"*", eml_filename, 0, TRUE);
1989 Ustrncpy(spooled_message_id, message_id, sizeof(spooled_message_id));
1991 /* don't set no_mbox_unspool; at present, there's no way for it to become
1992 set, but if that changes, then it should apply to these tests too */
1995 /* silence static analysis tools */
2005 if (!malware_default_re)
2006 malware_default_re = regex_must_compile(malware_regex_default, FALSE, TRUE);
2008 drweb_re = regex_must_compile(drweb_re_str, FALSE, TRUE);
2010 fsec_re = regex_must_compile(fsec_re_str, FALSE, TRUE);
2012 kav_re_sus = regex_must_compile(kav_re_sus_str, FALSE, TRUE);
2014 kav_re_inf = regex_must_compile(kav_re_inf_str, FALSE, TRUE);
2016 ava_re_clean = regex_must_compile(ava_re_clean_str, FALSE, TRUE);
2018 ava_re_virus = regex_must_compile(ava_re_virus_str, FALSE, TRUE);
2021 #endif /*WITH_CONTENT_SCAN*/