Fix build with content-scan enabled but all malware types disabled
[exim.git] / src / src / malware.c
1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
4
5 /* Copyright (c) Tom Kistner <tom@duncanthrax.net> 2003 - 2015
6 * License: GPL
7 * Copyright (c) The Exim Maintainers 2015 - 2018
8 */
9
10 /* Code for calling virus (malware) scanners. Called from acl.c. */
11
12 #include "exim.h"
13 #ifdef WITH_CONTENT_SCAN /* entire file */
14
15 typedef enum {
16 #ifndef DISABLE_MAL_FFROTD
17 M_FPROTD,
18 #endif
19 #ifndef DISABLE_MAL_FFROT6D
20 M_FPROT6D,
21 #endif
22 #ifndef DISABLE_MAL_DRWEB
23 M_DRWEB,
24 #endif
25 #ifndef DISABLE_MAL_AVE
26 M_AVES,
27 #endif
28 #ifndef DISABLE_MAL_FSECURE
29 M_FSEC,
30 #endif
31 #ifndef DISABLE_MAL_KAV
32 M_KAVD,
33 #endif
34 #ifndef DISABLE_MAL_SOPHIE
35 M_SOPHIE,
36 #endif
37 #ifndef DISABLE_MAL_CLAM
38 M_CLAMD,
39 #endif
40 #ifndef DISABLE_MAL_MKS
41 M_MKSD,
42 #endif
43 #ifndef DISABLE_MAL_AVAST
44 M_AVAST,
45 #endif
46 #ifndef DISABLE_MAL_SOCK
47 M_SOCK,
48 #endif
49 #ifndef DISABLE_MAL_CMDLINE
50 M_CMDL,
51 #endif
52 M_DUMMY
53 } scanner_t;
54 typedef enum {MC_NONE, MC_TCP, MC_UNIX, MC_STRM} contype_t;
55 static struct scan
56 {
57 scanner_t scancode;
58 const uschar * name;
59 const uschar * options_default;
60 contype_t conn;
61 } m_scans[] =
62 {
63 #ifndef DISABLE_MAL_FFROTD
64 { M_FPROTD, US"f-protd", US"localhost 10200-10204", MC_TCP },
65 #endif
66 #ifndef DISABLE_MAL_FFROT6D
67 { M_FPROT6D, US"f-prot6d", US"localhost 10200", MC_TCP },
68 #endif
69 #ifndef DISABLE_MAL_DRWEB
70 { M_DRWEB, US"drweb", US"/usr/local/drweb/run/drwebd.sock", MC_STRM },
71 #endif
72 #ifndef DISABLE_MAL_AVE
73 { M_AVES, US"aveserver", US"/var/run/aveserver", MC_UNIX },
74 #endif
75 #ifndef DISABLE_MAL_FSECURE
76 { M_FSEC, US"fsecure", US"/var/run/.fsav", MC_UNIX },
77 #endif
78 #ifndef DISABLE_MAL_KAV
79 { M_KAVD, US"kavdaemon", US"/var/run/AvpCtl", MC_UNIX },
80 #endif
81 #ifndef DISABLE_MAL_SOPHIE
82 { M_SOPHIE, US"sophie", US"/var/run/sophie", MC_UNIX },
83 #endif
84 #ifndef DISABLE_MAL_CLAM
85 { M_CLAMD, US"clamd", US"/tmp/clamd", MC_NONE },
86 #endif
87 #ifndef DISABLE_MAL_MKS
88 { M_MKSD, US"mksd", NULL, MC_NONE },
89 #endif
90 #ifndef DISABLE_MAL_AVAST
91 { M_AVAST, US"avast", US"/var/run/avast/scan.sock", MC_STRM },
92 #endif
93 #ifndef DISABLE_MAL_SOCK
94 { M_SOCK, US"sock", US"/tmp/malware.sock", MC_STRM },
95 #endif
96 #ifndef DISABLE_MAL_CMDLINE
97 { M_CMDL, US"cmdline", NULL, MC_NONE },
98 #endif
99 { -1, NULL, NULL, MC_NONE } /* end-marker */
100 };
101
102 /******************************************************************************/
103 # ifdef MACRO_PREDEF /* build solely to predefine macros */
104
105 # include "macro_predef.h"
106
107 void
108 features_malware(void)
109 {
110 const struct scan * sc;
111 const uschar * s;
112 uschar * t;
113 uschar buf[64];
114
115 spf(buf, sizeof(buf), US"_HAVE_MALWARE_");
116
117 for (sc = m_scans; sc->scancode != -1; sc++)
118 {
119 for(s = sc->name, t = buf+14; *s; s++) if (*s != '-') *t++ = toupper(*s);
120 *t = '\0';
121 builtin_macro_create(buf);
122 }
123 }
124
125 /******************************************************************************/
126 # else /*!MACRO_PREDEF, main build*/
127
128
129 #define MALWARE_TIMEOUT 120 /* default timeout, seconds */
130
131 static const uschar * malware_regex_default = US ".+";
132 static const pcre * malware_default_re = NULL;
133
134
135
136 #ifndef DISABLE_MAL_CLAM
137 /* The maximum number of clamd servers that are supported in the configuration */
138 # define MAX_CLAMD_SERVERS 32
139 # define MAX_CLAMD_SERVERS_S "32"
140
141 typedef struct clamd_address {
142 uschar * hostspec;
143 unsigned tcp_port;
144 unsigned retry;
145 } clamd_address;
146 #endif
147
148
149 #ifndef DISABLE_MAL_DRWEB
150 # define DRWEBD_SCAN_CMD (1) /* scan file, buffer or diskfile */
151 # define DRWEBD_RETURN_VIRUSES (1<<0) /* ask daemon return to us viruses names from report */
152 # define DRWEBD_IS_MAIL (1<<19) /* say to daemon that format is "archive MAIL" */
153
154 # define DERR_READ_ERR (1<<0) /* read error */
155 # define DERR_NOMEMORY (1<<2) /* no memory */
156 # define DERR_TIMEOUT (1<<9) /* scan timeout has run out */
157 # define DERR_BAD_CALL (1<<15) /* wrong command */
158
159 static const uschar * drweb_re_str = US "infected\\swith\\s*(.+?)$";
160 static const pcre * drweb_re = NULL;
161 #endif
162
163 #ifndef DISABLE_MAL_FSECURE
164 static const uschar * fsec_re_str = US "\\S{0,5}INFECTED\\t[^\\t]*\\t([^\\t]+)\\t\\S*$";
165 static const pcre * fsec_re = NULL;
166 #endif
167
168 #ifndef DISABLE_MAL_KAV
169 static const uschar * kav_re_sus_str = US "suspicion:\\s*(.+?)\\s*$";
170 static const uschar * kav_re_inf_str = US "infected:\\s*(.+?)\\s*$";
171 static const pcre * kav_re_sus = NULL;
172 static const pcre * kav_re_inf = NULL;
173 #endif
174
175 #ifndef DISABLE_MAL_AVAST
176 static const uschar * ava_re_clean_str = US "(?!\\\\)\\t\\[\\+\\]";
177 static const uschar * ava_re_virus_str = US "(?!\\\\)\\t\\[L\\]\\d+\\.0\\t0\\s(.*)";
178 static const uschar * ava_re_error_str = US "(?!\\\\)\\t\\[E\\]\\d+\\.0\\tError\\s\\d+\\s(.*)";
179 static const pcre * ava_re_clean = NULL;
180 static const pcre * ava_re_virus = NULL;
181 static const pcre * ava_re_error = NULL;
182 #endif
183
184 #ifndef DISABLE_MAL_FFROT6D
185 static const uschar * fprot6d_re_error_str = US "^\\d+\\s<(.+?)>$";
186 static const uschar * fprot6d_re_virus_str = US "^\\d+\\s<infected:\\s+(.+?)>\\s+.+$";
187 static const pcre * fprot6d_re_error = NULL;
188 static const pcre * fprot6d_re_virus = NULL;
189 #endif
190
191
192
193 /******************************************************************************/
194
195 #ifndef DISABLE_MAL_KAV
196 /* Routine to check whether a system is big- or little-endian.
197 Ripped from http://www.faqs.org/faqs/graphics/fileformats-faq/part4/section-7.html
198 Needed for proper kavdaemon implementation. Sigh. */
199 # define BIG_MY_ENDIAN 0
200 # define LITTLE_MY_ENDIAN 1
201 static int test_byte_order(void);
202 static inline int
203 test_byte_order()
204 {
205 short int word = 0x0001;
206 char *byte = CS &word;
207 return(byte[0] ? LITTLE_MY_ENDIAN : BIG_MY_ENDIAN);
208 }
209 #endif
210
211 BOOL malware_ok = FALSE;
212
213 /* Gross hacks for the -bmalware option; perhaps we should just create
214 the scan directory normally for that case, but look into rigging up the
215 needed header variables if not already set on the command-line? */
216 extern int spool_mbox_ok;
217 extern uschar spooled_message_id[MESSAGE_ID_LENGTH+1];
218
219
220 /* Some (currently avast only) use backslash escaped whitespace,
221 this function undoes these escapes */
222
223 static inline void
224 unescape(uschar *p)
225 {
226 uschar *p0;
227 for (; *p; ++p)
228 if (*p == '\\' && (isspace(p[1]) || p[1] == '\\'))
229 for (p0 = p; *p0; ++p0) *p0 = p0[1];
230 }
231
232 /* --- malware_*_defer --- */
233 static inline int
234 malware_panic_defer(const uschar * str)
235 {
236 log_write(0, LOG_MAIN|LOG_PANIC, "malware acl condition: %s", str);
237 return DEFER;
238 }
239 static inline int
240 malware_log_defer(const uschar * str)
241 {
242 log_write(0, LOG_MAIN, "malware acl condition: %s", str);
243 return DEFER;
244 }
245 /* --- m_*_defer --- */
246 static inline int
247 m_panic_defer(struct scan * scanent, const uschar * hostport,
248 const uschar * str)
249 {
250 return malware_panic_defer(string_sprintf("%s %s : %s",
251 scanent->name, hostport ? hostport : CUS"", str));
252 }
253 static inline int
254 m_log_defer(struct scan * scanent, const uschar * hostport,
255 const uschar * str)
256 {
257 return malware_log_defer(string_sprintf("%s %s : %s",
258 scanent->name, hostport ? hostport : CUS"", str));
259 }
260 /* --- m_*_defer_3 */
261 static inline int
262 m_panic_defer_3(struct scan * scanent, const uschar * hostport,
263 const uschar * str, int fd_to_close)
264 {
265 (void) close(fd_to_close);
266 return m_panic_defer(scanent, hostport, str);
267 }
268
269 /*************************************************/
270
271 #ifndef DISABLE_MAL_CLAM
272 /* Only used by the Clamav code, which is working from a list of servers and
273 uses the returned in_addr to get a second connection to the same system.
274 */
275 static inline int
276 m_tcpsocket(const uschar * hostname, unsigned int port,
277 host_item * host, uschar ** errstr, const blob * fastopen_blob)
278 {
279 return ip_connectedsocket(SOCK_STREAM, hostname, port, port, 5,
280 host, errstr, fastopen_blob);
281 }
282 #endif
283
284 static int
285 m_sock_send(int sock, uschar * buf, int cnt, uschar ** errstr)
286 {
287 if (send(sock, buf, cnt, 0) < 0)
288 {
289 int err = errno;
290 (void)close(sock);
291 *errstr = string_sprintf("unable to send to socket (%s): %s",
292 buf, strerror(err));
293 return -1;
294 }
295 return sock;
296 }
297
298 static const pcre *
299 m_pcre_compile(const uschar * re, uschar ** errstr)
300 {
301 const uschar * rerror;
302 int roffset;
303 const pcre * cre;
304
305 cre = pcre_compile(CS re, PCRE_COPT, (const char **)&rerror, &roffset, NULL);
306 if (!cre)
307 *errstr= string_sprintf("regular expression error in '%s': %s at offset %d",
308 re, rerror, roffset);
309 return cre;
310 }
311
312 uschar *
313 m_pcre_exec(const pcre * cre, uschar * text)
314 {
315 int ovector[10*3];
316 int i = pcre_exec(cre, NULL, CS text, Ustrlen(text), 0, 0,
317 ovector, nelem(ovector));
318 uschar * substr = NULL;
319 if (i >= 2) /* Got it */
320 pcre_get_substring(CS text, ovector, i, 1, (const char **) &substr);
321 return substr;
322 }
323
324 static const pcre *
325 m_pcre_nextinlist(const uschar ** list, int * sep,
326 char * listerr, uschar ** errstr)
327 {
328 const uschar * list_ele;
329 const pcre * cre = NULL;
330
331 if (!(list_ele = string_nextinlist(list, sep, NULL, 0)))
332 *errstr = US listerr;
333 else
334 {
335 DEBUG(D_acl) debug_printf_indent("%15s%10s'%s'\n", "", "RE: ",
336 string_printing(list_ele));
337 cre = m_pcre_compile(CUS list_ele, errstr);
338 }
339 return cre;
340 }
341
342 /*
343 Simple though inefficient wrapper for reading a line. Drop CRs and the
344 trailing newline. Can return early on buffer full. Null-terminate.
345 Apply initial timeout if no data ready.
346
347 Return: number of chars - zero for an empty line
348 -1 on EOF
349 -2 on timeout or error
350 */
351 static int
352 recv_line(int fd, uschar * buffer, int bsize, int tmo)
353 {
354 uschar * p = buffer;
355 ssize_t rcv;
356 BOOL ok = FALSE;
357
358 if (!fd_ready(fd, tmo-time(NULL)))
359 return -2;
360
361 /*XXX tmo handling assumes we always get a whole line */
362 /* read until \n */
363 errno = 0;
364 while ((rcv = read(fd, p, 1)) > 0)
365 {
366 ok = TRUE;
367 if (p-buffer > bsize-2) break;
368 if (*p == '\n') break;
369 if (*p != '\r') p++;
370 }
371 if (!ok)
372 {
373 DEBUG(D_acl) debug_printf_indent("Malware scan: read %s (%s)\n",
374 rcv==0 ? "EOF" : "error", strerror(errno));
375 return rcv==0 ? -1 : -2;
376 }
377 *p = '\0';
378
379 DEBUG(D_acl) debug_printf_indent("Malware scan: read '%s'\n", buffer);
380 return p - buffer;
381 }
382
383 /* return TRUE iff size as requested */
384 static BOOL
385 recv_len(int sock, void * buf, int size, int tmo)
386 {
387 return fd_ready(sock, tmo-time(NULL))
388 ? recv(sock, buf, size, 0) == size
389 : FALSE;
390 }
391
392
393
394 #ifndef DISABLE_MAL_MKS
395 /* ============= private routines for the "mksd" scanner type ============== */
396
397 # include <sys/uio.h>
398
399 static inline int
400 mksd_writev (int sock, struct iovec * iov, int iovcnt)
401 {
402 int i;
403
404 for (;;)
405 {
406 do
407 i = writev (sock, iov, iovcnt);
408 while (i < 0 && errno == EINTR);
409 if (i <= 0)
410 {
411 (void) malware_panic_defer(
412 US"unable to write to mksd UNIX socket (/var/run/mksd/socket)");
413 return -1;
414 }
415 for (;;) /* check for short write */
416 if (i >= iov->iov_len)
417 {
418 if (--iovcnt == 0)
419 return 0;
420 i -= iov->iov_len;
421 iov++;
422 }
423 else
424 {
425 iov->iov_len -= i;
426 iov->iov_base = CS iov->iov_base + i;
427 break;
428 }
429 }
430 }
431
432 static inline int
433 mksd_read_lines (int sock, uschar *av_buffer, int av_buffer_size, int tmo)
434 {
435 client_conn_ctx cctx = {.sock = sock};
436 int offset = 0;
437 int i;
438
439 do
440 {
441 i = ip_recv(&cctx, av_buffer+offset, av_buffer_size-offset, tmo-time(NULL));
442 if (i <= 0)
443 {
444 (void) malware_panic_defer(US"unable to read from mksd UNIX socket (/var/run/mksd/socket)");
445 return -1;
446 }
447
448 offset += i;
449 /* offset == av_buffer_size -> buffer full */
450 if (offset == av_buffer_size)
451 {
452 (void) malware_panic_defer(US"malformed reply received from mksd");
453 return -1;
454 }
455 } while (av_buffer[offset-1] != '\n');
456
457 av_buffer[offset] = '\0';
458 return offset;
459 }
460
461 static inline int
462 mksd_parse_line(struct scan * scanent, char * line)
463 {
464 char *p;
465
466 switch (*line)
467 {
468 case 'O': /* OK */
469 return OK;
470
471 case 'E':
472 case 'A': /* ERR */
473 if ((p = strchr (line, '\n')) != NULL)
474 *p = '\0';
475 return m_panic_defer(scanent, NULL,
476 string_sprintf("scanner failed: %s", line));
477
478 default: /* VIR */
479 if ((p = strchr (line, '\n')) != NULL)
480 {
481 *p = '\0';
482 if ( p-line > 5
483 && line[3] == ' '
484 && (p = strchr(line+4, ' ')) != NULL
485 && p-line > 4
486 )
487 {
488 *p = '\0';
489 malware_name = string_copy(US line+4);
490 return OK;
491 }
492 }
493 return m_panic_defer(scanent, NULL,
494 string_sprintf("malformed reply received: %s", line));
495 }
496 }
497
498 static int
499 mksd_scan_packed(struct scan * scanent, int sock, const uschar * scan_filename,
500 int tmo)
501 {
502 struct iovec iov[3];
503 const char *cmd = "MSQ\n";
504 uschar av_buffer[1024];
505
506 iov[0].iov_base = (void *) cmd;
507 iov[0].iov_len = 3;
508 iov[1].iov_base = (void *) scan_filename;
509 iov[1].iov_len = Ustrlen(scan_filename);
510 iov[2].iov_base = (void *) (cmd + 3);
511 iov[2].iov_len = 1;
512
513 if (mksd_writev (sock, iov, 3) < 0)
514 return DEFER;
515
516 if (mksd_read_lines (sock, av_buffer, sizeof (av_buffer), tmo) < 0)
517 return DEFER;
518
519 return mksd_parse_line (scanent, CS av_buffer);
520 }
521 #endif /* MKSD */
522
523
524 #ifndef DISABLE_MAL_CLAM
525 static int
526 clamd_option(clamd_address * cd, const uschar * optstr, int * subsep)
527 {
528 uschar * s;
529
530 cd->retry = 0;
531 while ((s = string_nextinlist(&optstr, subsep, NULL, 0)))
532 if (Ustrncmp(s, "retry=", 6) == 0)
533 {
534 int sec = readconf_readtime((s += 6), '\0', FALSE);
535 if (sec < 0)
536 return FAIL;
537 cd->retry = sec;
538 }
539 else
540 return FAIL;
541 return OK;
542 }
543 #endif
544
545
546
547 /*************************************************
548 * Scan content for malware *
549 *************************************************/
550
551 /* This is an internal interface for scanning an email; the normal interface
552 is via malware(), or there's malware_in_file() used for testing/debugging.
553
554 Arguments:
555 malware_re match condition for "malware="
556 scan_filename the file holding the email to be scanned, if we're faking
557 this up for the -bmalware test, else NULL
558 timeout if nonzero, non-default timeoutl
559
560 Returns: Exim message processing code (OK, FAIL, DEFER, ...)
561 where true means malware was found (condition applies)
562 */
563 static int
564 malware_internal(const uschar * malware_re, const uschar * scan_filename,
565 int timeout)
566 {
567 int sep = 0;
568 const uschar *av_scanner_work = av_scanner;
569 uschar *scanner_name;
570 unsigned long mbox_size;
571 FILE *mbox_file;
572 const pcre *re;
573 uschar * errstr;
574 struct scan * scanent;
575 const uschar * scanner_options;
576 client_conn_ctx malware_daemon_ctx = {.sock = -1};
577 time_t tmo;
578 uschar * eml_filename, * eml_dir;
579
580 if (!malware_re)
581 return FAIL; /* empty means "don't match anything" */
582
583 /* Ensure the eml mbox file is spooled up */
584
585 if (!(mbox_file = spool_mbox(&mbox_size, scan_filename, &eml_filename)))
586 return malware_panic_defer(US"error while creating mbox spool file");
587
588 /* None of our current scanners need the mbox file as a stream (they use
589 the name), so we can close it right away. Get the directory too. */
590
591 (void) fclose(mbox_file);
592 eml_dir = string_copyn(eml_filename, Ustrrchr(eml_filename, '/') - eml_filename);
593
594 /* parse 1st option */
595 if (strcmpic(malware_re, US"false") == 0 || Ustrcmp(malware_re,"0") == 0)
596 return FAIL; /* explicitly no matching */
597
598 /* special cases (match anything except empty) */
599 if ( strcmpic(malware_re,US"true") == 0
600 || Ustrcmp(malware_re,"*") == 0
601 || Ustrcmp(malware_re,"1") == 0
602 )
603 {
604 if ( !malware_default_re
605 && !(malware_default_re = m_pcre_compile(malware_regex_default, &errstr)))
606 return malware_panic_defer(errstr);
607 malware_re = malware_regex_default;
608 re = malware_default_re;
609 }
610
611 /* compile the regex, see if it works */
612 else if (!(re = m_pcre_compile(malware_re, &errstr)))
613 return malware_panic_defer(errstr);
614
615 /* if av_scanner starts with a dollar, expand it first */
616 if (*av_scanner == '$')
617 {
618 if (!(av_scanner_work = expand_string(av_scanner)))
619 return malware_panic_defer(
620 string_sprintf("av_scanner starts with $, but expansion failed: %s",
621 expand_string_message));
622
623 DEBUG(D_acl)
624 debug_printf_indent("Expanded av_scanner global: %s\n", av_scanner_work);
625 /* disable result caching in this case */
626 malware_name = NULL;
627 malware_ok = FALSE;
628 }
629
630 /* Do not scan twice (unless av_scanner is dynamic). */
631 if (!malware_ok)
632 {
633 /* find the scanner type from the av_scanner option */
634 if (!(scanner_name = string_nextinlist(&av_scanner_work, &sep, NULL, 0)))
635 return malware_panic_defer(US"av_scanner configuration variable is empty");
636 if (!timeout) timeout = MALWARE_TIMEOUT;
637 tmo = time(NULL) + timeout;
638
639 for (scanent = m_scans; ; scanent++)
640 {
641 if (!scanent->name)
642 return malware_panic_defer(string_sprintf("unknown scanner type '%s'",
643 scanner_name));
644 if (strcmpic(scanner_name, US scanent->name) != 0)
645 continue;
646 DEBUG(D_acl) debug_printf_indent("Malware scan: %s tmo=%s\n",
647 scanner_name, readconf_printtime(timeout));
648
649 if (!(scanner_options = string_nextinlist(&av_scanner_work, &sep, NULL, 0)))
650 scanner_options = scanent->options_default;
651 if (scanent->conn == MC_NONE)
652 break;
653
654 DEBUG(D_acl) debug_printf_indent("%15s%10s%s\n", "", "socket: ", scanner_options);
655 switch(scanent->conn)
656 {
657 case MC_TCP:
658 malware_daemon_ctx.sock = ip_tcpsocket(scanner_options, &errstr, 5); break;
659 case MC_UNIX:
660 malware_daemon_ctx.sock = ip_unixsocket(scanner_options, &errstr); break;
661 case MC_STRM:
662 malware_daemon_ctx.sock = ip_streamsocket(scanner_options, &errstr, 5); break;
663 default:
664 /* compiler quietening */ break;
665 }
666 if (malware_daemon_ctx.sock < 0)
667 return m_panic_defer(scanent, CUS callout_address, errstr);
668 break;
669 }
670
671 switch (scanent->scancode)
672 {
673 #ifndef DISABLE_MAL_FFROTD
674 case M_FPROTD: /* "f-protd" scanner type -------------------------------- */
675 {
676 uschar *fp_scan_option;
677 unsigned int detected=0, par_count=0;
678 uschar * scanrequest;
679 uschar buf[32768], *strhelper, *strhelper2;
680 uschar * malware_name_internal = NULL;
681 int len;
682
683 scanrequest = string_sprintf("GET %s", eml_filename);
684
685 while ((fp_scan_option = string_nextinlist(&av_scanner_work, &sep,
686 NULL, 0)))
687 {
688 scanrequest = string_sprintf("%s%s%s", scanrequest,
689 par_count ? "%20" : "?", fp_scan_option);
690 par_count++;
691 }
692 scanrequest = string_sprintf("%s HTTP/1.0\r\n\r\n", scanrequest);
693 DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s: %s\n",
694 scanner_name, scanrequest);
695
696 /* send scan request */
697 if (m_sock_send(malware_daemon_ctx.sock, scanrequest, Ustrlen(scanrequest)+1, &errstr) < 0)
698 return m_panic_defer(scanent, CUS callout_address, errstr);
699
700 while ((len = recv_line(malware_daemon_ctx.sock, buf, sizeof(buf), tmo)) >= 0)
701 if (len > 0)
702 {
703 if (Ustrstr(buf, US"<detected type=\"") != NULL)
704 detected = 1;
705 else if (detected && (strhelper = Ustrstr(buf, US"<name>")))
706 {
707 if ((strhelper2 = Ustrstr(buf, US"</name>")) != NULL)
708 {
709 *strhelper2 = '\0';
710 malware_name_internal = string_copy(strhelper+6);
711 }
712 }
713 else if (Ustrstr(buf, US"<summary code=\""))
714 {
715 malware_name = Ustrstr(buf, US"<summary code=\"11\">")
716 ? malware_name_internal : NULL;
717 break;
718 }
719 }
720 if (len < -1)
721 {
722 (void)close(malware_daemon_ctx.sock);
723 return DEFER;
724 }
725 break;
726 } /* f-protd */
727 #endif
728
729 #ifndef DISABLE_MAL_FFROT6D
730 case M_FPROT6D: /* "f-prot6d" scanner type ----------------------------------- */
731 {
732 int bread;
733 uschar * e;
734 uschar * linebuffer;
735 uschar * scanrequest;
736 uschar av_buffer[1024];
737
738 if ((!fprot6d_re_virus && !(fprot6d_re_virus = m_pcre_compile(fprot6d_re_virus_str, &errstr)))
739 || (!fprot6d_re_error && !(fprot6d_re_error = m_pcre_compile(fprot6d_re_error_str, &errstr))))
740 return malware_panic_defer(errstr);
741
742 scanrequest = string_sprintf("SCAN FILE %s\n", eml_filename);
743 DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s: %s\n",
744 scanner_name, scanrequest);
745
746 if (m_sock_send(malware_daemon_ctx.sock, scanrequest, Ustrlen(scanrequest), &errstr) < 0)
747 return m_panic_defer(scanent, CUS callout_address, errstr);
748
749 bread = ip_recv(&malware_daemon_ctx, av_buffer, sizeof(av_buffer), tmo-time(NULL));
750
751 if (bread <= 0)
752 return m_panic_defer_3(scanent, CUS callout_address,
753 string_sprintf("unable to read from socket (%s)", strerror(errno)),
754 malware_daemon_ctx.sock);
755
756 if (bread == sizeof(av_buffer))
757 return m_panic_defer_3(scanent, CUS callout_address,
758 US"buffer too small", malware_daemon_ctx.sock);
759
760 av_buffer[bread] = '\0';
761 linebuffer = string_copy(av_buffer);
762
763 m_sock_send(malware_daemon_ctx.sock, US"QUIT\n", 5, 0);
764
765 if ((e = m_pcre_exec(fprot6d_re_error, linebuffer)))
766 return m_panic_defer_3(scanent, CUS callout_address,
767 string_sprintf("scanner reported error (%s)", e), malware_daemon_ctx.sock);
768
769 if (!(malware_name = m_pcre_exec(fprot6d_re_virus, linebuffer)))
770 malware_name = NULL;
771
772 break;
773 } /* f-prot6d */
774 #endif
775
776 #ifndef DISABLE_MAL_DRWEB
777 case M_DRWEB: /* "drweb" scanner type ----------------------------------- */
778 /* v0.1 - added support for tcp sockets */
779 /* v0.0 - initial release -- support for unix sockets */
780 {
781 int result;
782 off_t fsize;
783 unsigned int fsize_uint;
784 uschar * tmpbuf, *drweb_fbuf;
785 int drweb_rc, drweb_cmd, drweb_flags = 0x0000, drweb_fd,
786 drweb_vnum, drweb_slen, drweb_fin = 0x0000;
787
788 /* prepare variables */
789 drweb_cmd = htonl(DRWEBD_SCAN_CMD);
790 drweb_flags = htonl(DRWEBD_RETURN_VIRUSES | DRWEBD_IS_MAIL);
791
792 if (*scanner_options != '/')
793 {
794 /* calc file size */
795 if ((drweb_fd = open(CCS eml_filename, O_RDONLY)) == -1)
796 return m_panic_defer_3(scanent, NULL,
797 string_sprintf("can't open spool file %s: %s",
798 eml_filename, strerror(errno)),
799 malware_daemon_ctx.sock);
800
801 if ((fsize = lseek(drweb_fd, 0, SEEK_END)) == -1)
802 {
803 int err;
804 badseek: err = errno;
805 (void)close(drweb_fd);
806 return m_panic_defer_3(scanent, NULL,
807 string_sprintf("can't seek spool file %s: %s",
808 eml_filename, strerror(err)),
809 malware_daemon_ctx.sock);
810 }
811 fsize_uint = (unsigned int) fsize;
812 if ((off_t)fsize_uint != fsize)
813 {
814 (void)close(drweb_fd);
815 return m_panic_defer_3(scanent, NULL,
816 string_sprintf("seeking spool file %s, size overflow",
817 eml_filename),
818 malware_daemon_ctx.sock);
819 }
820 drweb_slen = htonl(fsize);
821 if (lseek(drweb_fd, 0, SEEK_SET) < 0)
822 goto badseek;
823
824 DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s remote scan [%s]\n",
825 scanner_name, scanner_options);
826
827 /* send scan request */
828 if ((send(malware_daemon_ctx.sock, &drweb_cmd, sizeof(drweb_cmd), 0) < 0) ||
829 (send(malware_daemon_ctx.sock, &drweb_flags, sizeof(drweb_flags), 0) < 0) ||
830 (send(malware_daemon_ctx.sock, &drweb_fin, sizeof(drweb_fin), 0) < 0) ||
831 (send(malware_daemon_ctx.sock, &drweb_slen, sizeof(drweb_slen), 0) < 0))
832 {
833 (void)close(drweb_fd);
834 return m_panic_defer_3(scanent, CUS callout_address, string_sprintf(
835 "unable to send commands to socket (%s)", scanner_options),
836 malware_daemon_ctx.sock);
837 }
838
839 if (!(drweb_fbuf = US malloc(fsize_uint)))
840 {
841 (void)close(drweb_fd);
842 return m_panic_defer_3(scanent, NULL,
843 string_sprintf("unable to allocate memory %u for file (%s)",
844 fsize_uint, eml_filename),
845 malware_daemon_ctx.sock);
846 }
847
848 if ((result = read (drweb_fd, drweb_fbuf, fsize)) == -1)
849 {
850 int err = errno;
851 (void)close(drweb_fd);
852 free(drweb_fbuf);
853 return m_panic_defer_3(scanent, NULL,
854 string_sprintf("can't read spool file %s: %s",
855 eml_filename, strerror(err)),
856 malware_daemon_ctx.sock);
857 }
858 (void)close(drweb_fd);
859
860 /* send file body to socket */
861 if (send(malware_daemon_ctx.sock, drweb_fbuf, fsize, 0) < 0)
862 {
863 free(drweb_fbuf);
864 return m_panic_defer_3(scanent, CUS callout_address, string_sprintf(
865 "unable to send file body to socket (%s)", scanner_options),
866 malware_daemon_ctx.sock);
867 }
868 }
869 else
870 {
871 drweb_slen = htonl(Ustrlen(eml_filename));
872
873 DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s local scan [%s]\n",
874 scanner_name, scanner_options);
875
876 /* send scan request */
877 if ((send(malware_daemon_ctx.sock, &drweb_cmd, sizeof(drweb_cmd), 0) < 0) ||
878 (send(malware_daemon_ctx.sock, &drweb_flags, sizeof(drweb_flags), 0) < 0) ||
879 (send(malware_daemon_ctx.sock, &drweb_slen, sizeof(drweb_slen), 0) < 0) ||
880 (send(malware_daemon_ctx.sock, eml_filename, Ustrlen(eml_filename), 0) < 0) ||
881 (send(malware_daemon_ctx.sock, &drweb_fin, sizeof(drweb_fin), 0) < 0))
882 return m_panic_defer_3(scanent, CUS callout_address, string_sprintf(
883 "unable to send commands to socket (%s)", scanner_options),
884 malware_daemon_ctx.sock);
885 }
886
887 /* wait for result */
888 if (!recv_len(malware_daemon_ctx.sock, &drweb_rc, sizeof(drweb_rc), tmo))
889 return m_panic_defer_3(scanent, CUS callout_address,
890 US"unable to read return code", malware_daemon_ctx.sock);
891 drweb_rc = ntohl(drweb_rc);
892
893 if (!recv_len(malware_daemon_ctx.sock, &drweb_vnum, sizeof(drweb_vnum), tmo))
894 return m_panic_defer_3(scanent, CUS callout_address,
895 US"unable to read the number of viruses", malware_daemon_ctx.sock);
896 drweb_vnum = ntohl(drweb_vnum);
897
898 /* "virus(es) found" if virus number is > 0 */
899 if (drweb_vnum)
900 {
901 int i;
902 gstring * g = NULL;
903
904 /* setup default virus name */
905 malware_name = US"unknown";
906
907 /* set up match regex */
908 if (!drweb_re)
909 drweb_re = m_pcre_compile(drweb_re_str, &errstr);
910
911 /* read and concatenate virus names into one string */
912 for (i = 0; i < drweb_vnum; i++)
913 {
914 int ovector[10*3];
915
916 /* read the size of report */
917 if (!recv_len(malware_daemon_ctx.sock, &drweb_slen, sizeof(drweb_slen), tmo))
918 return m_panic_defer_3(scanent, CUS callout_address,
919 US"cannot read report size", malware_daemon_ctx.sock);
920 drweb_slen = ntohl(drweb_slen);
921 tmpbuf = store_get(drweb_slen);
922
923 /* read report body */
924 if (!recv_len(malware_daemon_ctx.sock, tmpbuf, drweb_slen, tmo))
925 return m_panic_defer_3(scanent, CUS callout_address,
926 US"cannot read report string", malware_daemon_ctx.sock);
927 tmpbuf[drweb_slen] = '\0';
928
929 /* try matcher on the line, grab substring */
930 result = pcre_exec(drweb_re, NULL, CS tmpbuf, Ustrlen(tmpbuf), 0, 0,
931 ovector, nelem(ovector));
932 if (result >= 2)
933 {
934 const char * pre_malware_nb;
935
936 pcre_get_substring(CS tmpbuf, ovector, result, 1, &pre_malware_nb);
937
938 if (i==0) /* the first name we just copy to malware_name */
939 g = string_cat(NULL, US pre_malware_nb);
940
941 /*XXX could be string_append_listele? */
942 else /* concatenate each new virus name to previous */
943 g = string_append(g, 2, "/", pre_malware_nb);
944
945 pcre_free_substring(pre_malware_nb);
946 }
947 }
948 malware_name = string_from_gstring(g);
949 }
950 else
951 {
952 const char *drweb_s = NULL;
953
954 if (drweb_rc & DERR_READ_ERR) drweb_s = "read error";
955 if (drweb_rc & DERR_NOMEMORY) drweb_s = "no memory";
956 if (drweb_rc & DERR_TIMEOUT) drweb_s = "timeout";
957 if (drweb_rc & DERR_BAD_CALL) drweb_s = "wrong command";
958 /* retcodes DERR_SYMLINK, DERR_NO_REGFILE, DERR_SKIPPED.
959 * DERR_TOO_BIG, DERR_TOO_COMPRESSED, DERR_SPAM,
960 * DERR_CRC_ERROR, DERR_READSOCKET, DERR_WRITE_ERR
961 * and others are ignored */
962 if (drweb_s)
963 return m_panic_defer_3(scanent, CUS callout_address,
964 string_sprintf("drweb daemon retcode 0x%x (%s)", drweb_rc, drweb_s),
965 malware_daemon_ctx.sock);
966
967 /* no virus found */
968 malware_name = NULL;
969 }
970 break;
971 } /* drweb */
972 #endif
973
974 #ifndef DISABLE_MAL_AVE
975 case M_AVES: /* "aveserver" scanner type -------------------------------- */
976 {
977 uschar buf[32768];
978 int result;
979
980 /* read aveserver's greeting and see if it is ready (2xx greeting) */
981 buf[0] = 0;
982 recv_line(malware_daemon_ctx.sock, buf, sizeof(buf), tmo);
983
984 if (buf[0] != '2') /* aveserver is having problems */
985 return m_panic_defer_3(scanent, CUS callout_address,
986 string_sprintf("unavailable (Responded: %s).",
987 ((buf[0] != 0) ? buf : US "nothing") ),
988 malware_daemon_ctx.sock);
989
990 /* prepare our command */
991 (void)string_format(buf, sizeof(buf), "SCAN bPQRSTUW %s\r\n",
992 eml_filename);
993
994 /* and send it */
995 DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s %s\n",
996 scanner_name, buf);
997 if (m_sock_send(malware_daemon_ctx.sock, buf, Ustrlen(buf), &errstr) < 0)
998 return m_panic_defer(scanent, CUS callout_address, errstr);
999
1000 malware_name = NULL;
1001 result = 0;
1002 /* read response lines, find malware name and final response */
1003 while (recv_line(malware_daemon_ctx.sock, buf, sizeof(buf), tmo) > 0)
1004 {
1005 if (buf[0] == '2')
1006 break;
1007 if (buf[0] == '5') /* aveserver is having problems */
1008 {
1009 result = m_panic_defer(scanent, CUS callout_address,
1010 string_sprintf("unable to scan file %s (Responded: %s).",
1011 eml_filename, buf));
1012 break;
1013 }
1014 if (Ustrncmp(buf,"322",3) == 0)
1015 {
1016 uschar *p = Ustrchr(&buf[4], ' ');
1017 *p = '\0';
1018 malware_name = string_copy(&buf[4]);
1019 }
1020 }
1021
1022 if (m_sock_send(malware_daemon_ctx.sock, US"quit\r\n", 6, &errstr) < 0)
1023 return m_panic_defer(scanent, CUS callout_address, errstr);
1024
1025 /* read aveserver's greeting and see if it is ready (2xx greeting) */
1026 buf[0] = 0;
1027 recv_line(malware_daemon_ctx.sock, buf, sizeof(buf), tmo);
1028
1029 if (buf[0] != '2') /* aveserver is having problems */
1030 return m_panic_defer_3(scanent, CUS callout_address,
1031 string_sprintf("unable to quit dialogue (Responded: %s).",
1032 ((buf[0] != 0) ? buf : US "nothing") ),
1033 malware_daemon_ctx.sock);
1034
1035 if (result == DEFER)
1036 {
1037 (void)close(malware_daemon_ctx.sock);
1038 return DEFER;
1039 }
1040 break;
1041 } /* aveserver */
1042 #endif
1043
1044 #ifndef DISABLE_MAL_FSECURE
1045 case M_FSEC: /* "fsecure" scanner type ---------------------------------- */
1046 {
1047 int i, j, bread = 0;
1048 uschar * file_name;
1049 uschar av_buffer[1024];
1050 static uschar *cmdopt[] = { US"CONFIGURE\tARCHIVE\t1\n",
1051 US"CONFIGURE\tTIMEOUT\t0\n",
1052 US"CONFIGURE\tMAXARCH\t5\n",
1053 US"CONFIGURE\tMIME\t1\n" };
1054
1055 malware_name = NULL;
1056
1057 DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s scan [%s]\n",
1058 scanner_name, scanner_options);
1059 /* pass options */
1060 memset(av_buffer, 0, sizeof(av_buffer));
1061 for (i = 0; i != nelem(cmdopt); i++)
1062 {
1063
1064 if (m_sock_send(malware_daemon_ctx.sock, cmdopt[i], Ustrlen(cmdopt[i]), &errstr) < 0)
1065 return m_panic_defer(scanent, CUS callout_address, errstr);
1066
1067 bread = ip_recv(&malware_daemon_ctx, av_buffer, sizeof(av_buffer), tmo-time(NULL));
1068 if (bread > 0) av_buffer[bread]='\0';
1069 if (bread < 0)
1070 return m_panic_defer_3(scanent, CUS callout_address,
1071 string_sprintf("unable to read answer %d (%s)", i, strerror(errno)),
1072 malware_daemon_ctx.sock);
1073 for (j = 0; j < bread; j++)
1074 if (av_buffer[j] == '\r' || av_buffer[j] == '\n')
1075 av_buffer[j] ='@';
1076 }
1077
1078 /* pass the mailfile to fsecure */
1079 file_name = string_sprintf("SCAN\t%s\n", eml_filename);
1080
1081 if (m_sock_send(malware_daemon_ctx.sock, file_name, Ustrlen(file_name), &errstr) < 0)
1082 return m_panic_defer(scanent, CUS callout_address, errstr);
1083
1084 /* set up match */
1085 /* todo also SUSPICION\t */
1086 if (!fsec_re)
1087 fsec_re = m_pcre_compile(fsec_re_str, &errstr);
1088
1089 /* read report, linewise. Apply a timeout as the Fsecure daemon
1090 sometimes wants an answer to "PING" but they won't tell us what */
1091 {
1092 uschar * p = av_buffer;
1093 uschar * q;
1094
1095 for (;;)
1096 {
1097 errno = ETIMEDOUT;
1098 i = av_buffer+sizeof(av_buffer)-p;
1099 if ((bread= ip_recv(&malware_daemon_ctx, p, i-1, tmo-time(NULL))) < 0)
1100 return m_panic_defer_3(scanent, CUS callout_address,
1101 string_sprintf("unable to read result (%s)", strerror(errno)),
1102 malware_daemon_ctx.sock);
1103
1104 for (p[bread] = '\0'; (q = Ustrchr(p, '\n')); p = q+1)
1105 {
1106 *q = '\0';
1107
1108 /* Really search for virus again? */
1109 if (!malware_name)
1110 /* try matcher on the line, grab substring */
1111 malware_name = m_pcre_exec(fsec_re, p);
1112
1113 if (Ustrstr(p, "OK\tScan ok."))
1114 goto fsec_found;
1115 }
1116
1117 /* copy down the trailing partial line then read another chunk */
1118 i = av_buffer+sizeof(av_buffer)-p;
1119 memmove(av_buffer, p, i);
1120 p = av_buffer+i;
1121 }
1122 }
1123
1124 fsec_found:
1125 break;
1126 } /* fsecure */
1127 #endif
1128
1129 #ifndef DISABLE_MAL_KAV
1130 case M_KAVD: /* "kavdaemon" scanner type -------------------------------- */
1131 {
1132 time_t t;
1133 uschar tmpbuf[1024];
1134 uschar * scanrequest;
1135 int kav_rc;
1136 unsigned long kav_reportlen;
1137 int bread;
1138 const pcre *kav_re;
1139 uschar *p;
1140
1141 /* get current date and time, build scan request */
1142 time(&t);
1143 /* pdp note: before the eml_filename parameter, this scanned the
1144 directory; not finding documentation, so we'll strip off the directory.
1145 The side-effect is that the test framework scanning may end up in
1146 scanning more than was requested, but for the normal interface, this is
1147 fine. */
1148
1149 strftime(CS tmpbuf, sizeof(tmpbuf), "%d %b %H:%M:%S", localtime(&t));
1150 scanrequest = string_sprintf("<0>%s:%s", CS tmpbuf, eml_filename);
1151 p = Ustrrchr(scanrequest, '/');
1152 if (p)
1153 *p = '\0';
1154
1155 DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s scan [%s]\n",
1156 scanner_name, scanner_options);
1157
1158 /* send scan request */
1159 if (m_sock_send(malware_daemon_ctx.sock, scanrequest, Ustrlen(scanrequest)+1, &errstr) < 0)
1160 return m_panic_defer(scanent, CUS callout_address, errstr);
1161
1162 /* wait for result */
1163 if (!recv_len(malware_daemon_ctx.sock, tmpbuf, 2, tmo))
1164 return m_panic_defer_3(scanent, CUS callout_address,
1165 US"unable to read 2 bytes from socket.", malware_daemon_ctx.sock);
1166
1167 /* get errorcode from one nibble */
1168 kav_rc = tmpbuf[ test_byte_order()==LITTLE_MY_ENDIAN ? 0 : 1 ] & 0x0F;
1169 switch(kav_rc)
1170 {
1171 case 5: case 6: /* improper kavdaemon configuration */
1172 return m_panic_defer_3(scanent, CUS callout_address,
1173 US"please reconfigure kavdaemon to NOT disinfect or remove infected files.",
1174 malware_daemon_ctx.sock);
1175 case 1:
1176 return m_panic_defer_3(scanent, CUS callout_address,
1177 US"reported 'scanning not completed' (code 1).", malware_daemon_ctx.sock);
1178 case 7:
1179 return m_panic_defer_3(scanent, CUS callout_address,
1180 US"reported 'kavdaemon damaged' (code 7).", malware_daemon_ctx.sock);
1181 }
1182
1183 /* code 8 is not handled, since it is ambiguous. It appears mostly on
1184 bounces where part of a file has been cut off */
1185
1186 /* "virus found" return codes (2-4) */
1187 if (kav_rc > 1 && kav_rc < 5)
1188 {
1189 int report_flag = 0;
1190
1191 /* setup default virus name */
1192 malware_name = US"unknown";
1193
1194 report_flag = tmpbuf[ test_byte_order() == LITTLE_MY_ENDIAN ? 1 : 0 ];
1195
1196 /* read the report, if available */
1197 if (report_flag == 1)
1198 {
1199 /* read report size */
1200 if (!recv_len(malware_daemon_ctx.sock, &kav_reportlen, 4, tmo))
1201 return m_panic_defer_3(scanent, CUS callout_address,
1202 US"cannot read report size", malware_daemon_ctx.sock);
1203
1204 /* it's possible that avp returns av_buffer[1] == 1 but the
1205 reportsize is 0 (!?) */
1206 if (kav_reportlen > 0)
1207 {
1208 /* set up match regex, depends on retcode */
1209 if (kav_rc == 3)
1210 {
1211 if (!kav_re_sus) kav_re_sus = m_pcre_compile(kav_re_sus_str, &errstr);
1212 kav_re = kav_re_sus;
1213 }
1214 else
1215 {
1216 if (!kav_re_inf) kav_re_inf = m_pcre_compile(kav_re_inf_str, &errstr);
1217 kav_re = kav_re_inf;
1218 }
1219
1220 /* read report, linewise. Using size from stream to read amount of data
1221 from same stream is safe enough. */
1222 /* coverity[tainted_data] */
1223 while (kav_reportlen > 0)
1224 {
1225 if ((bread = recv_line(malware_daemon_ctx.sock, tmpbuf, sizeof(tmpbuf), tmo)) < 0)
1226 break;
1227 kav_reportlen -= bread+1;
1228
1229 /* try matcher on the line, grab substring */
1230 if ((malware_name = m_pcre_exec(kav_re, tmpbuf)))
1231 break;
1232 }
1233 }
1234 }
1235 }
1236 else /* no virus found */
1237 malware_name = NULL;
1238
1239 break;
1240 }
1241 #endif
1242
1243 #ifndef DISABLE_MAL_CMDLINE
1244 case M_CMDL: /* "cmdline" scanner type ---------------------------------- */
1245 {
1246 const uschar *cmdline_scanner = scanner_options;
1247 const pcre *cmdline_trigger_re;
1248 const pcre *cmdline_regex_re;
1249 uschar * file_name;
1250 uschar * commandline;
1251 void (*eximsigchld)(int);
1252 void (*eximsigpipe)(int);
1253 FILE *scanner_out = NULL;
1254 int scanner_fd;
1255 FILE *scanner_record = NULL;
1256 uschar linebuffer[32767];
1257 int rcnt;
1258 int trigger = 0;
1259 uschar *p;
1260
1261 if (!cmdline_scanner)
1262 return m_panic_defer(scanent, NULL, errstr);
1263
1264 /* find scanner output trigger */
1265 cmdline_trigger_re = m_pcre_nextinlist(&av_scanner_work, &sep,
1266 "missing trigger specification", &errstr);
1267 if (!cmdline_trigger_re)
1268 return m_panic_defer(scanent, NULL, errstr);
1269
1270 /* find scanner name regex */
1271 cmdline_regex_re = m_pcre_nextinlist(&av_scanner_work, &sep,
1272 "missing virus name regex specification", &errstr);
1273 if (!cmdline_regex_re)
1274 return m_panic_defer(scanent, NULL, errstr);
1275
1276 /* prepare scanner call; despite the naming, file_name holds a directory
1277 name which is documented as the value given to %s. */
1278
1279 file_name = string_copy(eml_filename);
1280 p = Ustrrchr(file_name, '/');
1281 if (p)
1282 *p = '\0';
1283 commandline = string_sprintf(CS cmdline_scanner, file_name);
1284
1285 /* redirect STDERR too */
1286 commandline = string_sprintf("%s 2>&1", commandline);
1287
1288 DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s scan [%s]\n",
1289 scanner_name, commandline);
1290
1291 /* store exims signal handlers */
1292 eximsigchld = signal(SIGCHLD,SIG_DFL);
1293 eximsigpipe = signal(SIGPIPE,SIG_DFL);
1294
1295 if (!(scanner_out = popen(CS commandline,"r")))
1296 {
1297 int err = errno;
1298 signal(SIGCHLD,eximsigchld); signal(SIGPIPE,eximsigpipe);
1299 return m_panic_defer(scanent, NULL,
1300 string_sprintf("call (%s) failed: %s.", commandline, strerror(err)));
1301 }
1302 scanner_fd = fileno(scanner_out);
1303
1304 file_name = string_sprintf("%s/%s_scanner_output", eml_dir, message_id);
1305
1306 if (!(scanner_record = modefopen(file_name, "wb", SPOOL_MODE)))
1307 {
1308 int err = errno;
1309 (void) pclose(scanner_out);
1310 signal(SIGCHLD,eximsigchld); signal(SIGPIPE,eximsigpipe);
1311 return m_panic_defer(scanent, NULL, string_sprintf(
1312 "opening scanner output file (%s) failed: %s.",
1313 file_name, strerror(err)));
1314 }
1315
1316 /* look for trigger while recording output */
1317 while ((rcnt = recv_line(scanner_fd, linebuffer,
1318 sizeof(linebuffer), tmo)))
1319 {
1320 if (rcnt < 0)
1321 {
1322 int err = errno;
1323 if (rcnt == -1)
1324 break;
1325 (void) pclose(scanner_out);
1326 signal(SIGCHLD,eximsigchld); signal(SIGPIPE,eximsigpipe);
1327 return m_panic_defer(scanent, NULL, string_sprintf(
1328 "unable to read from scanner (%s): %s",
1329 commandline, strerror(err)));
1330 }
1331
1332 if (Ustrlen(linebuffer) > fwrite(linebuffer, 1, Ustrlen(linebuffer), scanner_record))
1333 {
1334 /* short write */
1335 (void) pclose(scanner_out);
1336 signal(SIGCHLD,eximsigchld); signal(SIGPIPE,eximsigpipe);
1337 return m_panic_defer(scanent, NULL, string_sprintf(
1338 "short write on scanner output file (%s).", file_name));
1339 }
1340 putc('\n', scanner_record);
1341 /* try trigger match */
1342 if ( !trigger
1343 && regex_match_and_setup(cmdline_trigger_re, linebuffer, 0, -1)
1344 )
1345 trigger = 1;
1346 }
1347
1348 (void)fclose(scanner_record);
1349 sep = pclose(scanner_out);
1350 signal(SIGCHLD,eximsigchld); signal(SIGPIPE,eximsigpipe);
1351 if (sep != 0)
1352 return m_panic_defer(scanent, NULL,
1353 sep == -1
1354 ? string_sprintf("running scanner failed: %s", strerror(sep))
1355 : string_sprintf("scanner returned error code: %d", sep));
1356
1357 if (trigger)
1358 {
1359 uschar * s;
1360 /* setup default virus name */
1361 malware_name = US"unknown";
1362
1363 /* re-open the scanner output file, look for name match */
1364 scanner_record = fopen(CS file_name, "rb");
1365 while (fgets(CS linebuffer, sizeof(linebuffer), scanner_record))
1366 {
1367 /* try match */
1368 if ((s = m_pcre_exec(cmdline_regex_re, linebuffer)))
1369 malware_name = s;
1370 }
1371 (void)fclose(scanner_record);
1372 }
1373 else /* no virus found */
1374 malware_name = NULL;
1375 break;
1376 } /* cmdline */
1377 #endif
1378
1379 #ifndef DISABLE_MAL_SOPHIE
1380 case M_SOPHIE: /* "sophie" scanner type --------------------------------- */
1381 {
1382 int bread = 0;
1383 uschar *p;
1384 uschar * file_name;
1385 uschar av_buffer[1024];
1386
1387 /* pass the scan directory to sophie */
1388 file_name = string_copy(eml_filename);
1389 if ((p = Ustrrchr(file_name, '/')))
1390 *p = '\0';
1391
1392 DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s scan [%s]\n",
1393 scanner_name, scanner_options);
1394
1395 if ( write(malware_daemon_ctx.sock, file_name, Ustrlen(file_name)) < 0
1396 || write(malware_daemon_ctx.sock, "\n", 1) != 1
1397 )
1398 return m_panic_defer_3(scanent, CUS callout_address,
1399 string_sprintf("unable to write to UNIX socket (%s)", scanner_options),
1400 malware_daemon_ctx.sock);
1401
1402 /* wait for result */
1403 memset(av_buffer, 0, sizeof(av_buffer));
1404 if ((bread = ip_recv(&malware_daemon_ctx, av_buffer, sizeof(av_buffer), tmo-time(NULL))) <= 0)
1405 return m_panic_defer_3(scanent, CUS callout_address,
1406 string_sprintf("unable to read from UNIX socket (%s)", scanner_options),
1407 malware_daemon_ctx.sock);
1408
1409 /* infected ? */
1410 if (av_buffer[0] == '1') {
1411 uschar * s = Ustrchr(av_buffer, '\n');
1412 if (s)
1413 *s = '\0';
1414 malware_name = string_copy(&av_buffer[2]);
1415 }
1416 else if (!strncmp(CS av_buffer, "-1", 2))
1417 return m_panic_defer_3(scanent, CUS callout_address,
1418 US"scanner reported error", malware_daemon_ctx.sock);
1419 else /* all ok, no virus */
1420 malware_name = NULL;
1421
1422 break;
1423 }
1424 #endif
1425
1426 #ifndef DISABLE_MAL_CLAM
1427 case M_CLAMD: /* "clamd" scanner type ----------------------------------- */
1428 {
1429 /* This code was originally contributed by David Saez */
1430 /* There are three scanning methods available to us:
1431 * (1) Use the SCAN command, pointing to a file in the filesystem
1432 * (2) Use the STREAM command, send the data on a separate port
1433 * (3) Use the zINSTREAM command, send the data inline
1434 * The zINSTREAM command was introduced with ClamAV 0.95, which marked
1435 * STREAM deprecated; see: http://wiki.clamav.net/bin/view/Main/UpgradeNotes095
1436 * In Exim, we use SCAN if using a Unix-domain socket or explicitly told that
1437 * the TCP-connected daemon is actually local; otherwise we use zINSTREAM
1438 * See Exim bug 926 for details. */
1439
1440 uschar *p, *vname, *result_tag;
1441 int bread=0;
1442 uschar av_buffer[1024];
1443 uschar *hostname = US"";
1444 host_item connhost;
1445 uschar *clamav_fbuf;
1446 int clam_fd, result;
1447 off_t fsize;
1448 unsigned int fsize_uint;
1449 BOOL use_scan_command = FALSE;
1450 clamd_address * cv[MAX_CLAMD_SERVERS];
1451 int num_servers = 0;
1452 uint32_t send_size, send_final_zeroblock;
1453 blob cmd_str;
1454
1455 /*XXX if unixdomain socket, only one server supported. Needs fixing;
1456 there's no reason we should not mix local and remote servers */
1457
1458 if (*scanner_options == '/')
1459 {
1460 clamd_address * cd;
1461 const uschar * sublist;
1462 int subsep = ' ';
1463
1464 /* Local file; so we def want to use_scan_command and don't want to try
1465 * passing IP/port combinations */
1466 use_scan_command = TRUE;
1467 cd = (clamd_address *) store_get(sizeof(clamd_address));
1468
1469 /* extract socket-path part */
1470 sublist = scanner_options;
1471 cd->hostspec = string_nextinlist(&sublist, &subsep, NULL, 0);
1472
1473 /* parse options */
1474 if (clamd_option(cd, sublist, &subsep) != OK)
1475 return m_panic_defer(scanent, NULL,
1476 string_sprintf("bad option '%s'", scanner_options));
1477 cv[0] = cd;
1478 }
1479 else
1480 {
1481 /* Go through the rest of the list of host/port and construct an array
1482 * of servers to try. The first one is the bit we just passed from
1483 * scanner_options so process that first and then scan the remainder of
1484 * the address buffer */
1485 do
1486 {
1487 clamd_address * cd;
1488 const uschar * sublist;
1489 int subsep = ' ';
1490 uschar * s;
1491
1492 /* The 'local' option means use the SCAN command over the network
1493 * socket (ie common file storage in use) */
1494 /*XXX we could accept this also as a local option? */
1495 if (strcmpic(scanner_options, US"local") == 0)
1496 {
1497 use_scan_command = TRUE;
1498 continue;
1499 }
1500
1501 cd = (clamd_address *) store_get(sizeof(clamd_address));
1502
1503 /* extract host and port part */
1504 sublist = scanner_options;
1505 if (!(cd->hostspec = string_nextinlist(&sublist, &subsep, NULL, 0)))
1506 {
1507 (void) m_panic_defer(scanent, NULL,
1508 string_sprintf("missing address: '%s'", scanner_options));
1509 continue;
1510 }
1511 if (!(s = string_nextinlist(&sublist, &subsep, NULL, 0)))
1512 {
1513 (void) m_panic_defer(scanent, NULL,
1514 string_sprintf("missing port: '%s'", scanner_options));
1515 continue;
1516 }
1517 cd->tcp_port = atoi(CS s);
1518
1519 /* parse options */
1520 /*XXX should these options be common over scanner types? */
1521 if (clamd_option(cd, sublist, &subsep) != OK)
1522 return m_panic_defer(scanent, NULL,
1523 string_sprintf("bad option '%s'", scanner_options));
1524
1525 cv[num_servers++] = cd;
1526 if (num_servers >= MAX_CLAMD_SERVERS)
1527 {
1528 (void) m_panic_defer(scanent, NULL,
1529 US"More than " MAX_CLAMD_SERVERS_S " clamd servers "
1530 "specified; only using the first " MAX_CLAMD_SERVERS_S );
1531 break;
1532 }
1533 } while ((scanner_options = string_nextinlist(&av_scanner_work, &sep,
1534 NULL, 0)));
1535
1536 /* check if we have at least one server */
1537 if (!num_servers)
1538 return m_panic_defer(scanent, NULL,
1539 US"no useable server addresses in malware configuration option.");
1540 }
1541
1542 /* See the discussion of response formats below to see why we really
1543 don't like colons in filenames when passing filenames to ClamAV. */
1544 if (use_scan_command && Ustrchr(eml_filename, ':'))
1545 return m_panic_defer(scanent, NULL,
1546 string_sprintf("local/SCAN mode incompatible with" \
1547 " : in path to email filename [%s]", eml_filename));
1548
1549 /* Set up the very first data we will be sending */
1550 if (!use_scan_command)
1551 { cmd_str.data = US"zINSTREAM"; cmd_str.len = 10; }
1552 else
1553 {
1554 cmd_str.data = string_sprintf("SCAN %s\n", eml_filename);
1555 cmd_str.len = Ustrlen(cmd_str.data);
1556 }
1557
1558 /* We have some network servers specified */
1559 if (num_servers)
1560 {
1561 /* Confirmed in ClamAV source (0.95.3) that the TCPAddr option of clamd
1562 * only supports AF_INET, but we should probably be looking to the
1563 * future and rewriting this to be protocol-independent anyway. */
1564
1565 while (num_servers > 0)
1566 {
1567 int i = random_number(num_servers);
1568 clamd_address * cd = cv[i];
1569
1570 DEBUG(D_acl) debug_printf_indent("trying server name %s, port %u\n",
1571 cd->hostspec, cd->tcp_port);
1572
1573 /* Lookup the host. This is to ensure that we connect to the same IP
1574 * on both connections (as one host could resolve to multiple ips) */
1575 for (;;)
1576 {
1577 /*XXX we trust that the cmd_str is ideempotent */
1578 if ((malware_daemon_ctx.sock = m_tcpsocket(cd->hostspec, cd->tcp_port,
1579 &connhost, &errstr, &cmd_str)) >= 0)
1580 {
1581 /* Connection successfully established with a server */
1582 hostname = cd->hostspec;
1583 cmd_str.len = 0;
1584 break;
1585 }
1586 if (cd->retry <= 0) break;
1587 while (cd->retry > 0) cd->retry = sleep(cd->retry);
1588 }
1589 if (malware_daemon_ctx.sock >= 0)
1590 break;
1591
1592 (void) m_panic_defer(scanent, CUS callout_address, errstr);
1593
1594 /* Remove the server from the list. XXX We should free the memory */
1595 num_servers--;
1596 for (; i < num_servers; i++)
1597 cv[i] = cv[i+1];
1598 }
1599
1600 if (num_servers == 0)
1601 return m_panic_defer(scanent, NULL, US"all servers failed");
1602 }
1603 else
1604 for (;;)
1605 {
1606 if ((malware_daemon_ctx.sock = ip_unixsocket(cv[0]->hostspec, &errstr)) >= 0)
1607 {
1608 hostname = cv[0]->hostspec;
1609 break;
1610 }
1611 if (cv[0]->retry <= 0)
1612 return m_panic_defer(scanent, CUS callout_address, errstr);
1613 while (cv[0]->retry > 0) cv[0]->retry = sleep(cv[0]->retry);
1614 }
1615
1616 /* have socket in variable "sock"; command to use is semi-independent of
1617 * the socket protocol. We use SCAN if is local (either Unix/local
1618 * domain socket, or explicitly told local) else we stream the data.
1619 * How we stream the data depends upon how we were built. */
1620
1621 if (!use_scan_command)
1622 {
1623 /* New protocol: "zINSTREAM\n" followed by a sequence of <length><data>
1624 chunks, <n> a 4-byte number (network order), terminated by a zero-length
1625 chunk. */
1626
1627 DEBUG(D_acl) debug_printf_indent(
1628 "Malware scan: issuing %s new-style remote scan (zINSTREAM)\n",
1629 scanner_name);
1630
1631 /* Pass the string to ClamAV (10 = "zINSTREAM\0"), if not already sent */
1632 if (cmd_str.len)
1633 if (send(malware_daemon_ctx.sock, cmd_str.data, cmd_str.len, 0) < 0)
1634 return m_panic_defer_3(scanent, CUS hostname,
1635 string_sprintf("unable to send zINSTREAM to socket (%s)",
1636 strerror(errno)),
1637 malware_daemon_ctx.sock);
1638
1639 /* calc file size */
1640 if ((clam_fd = open(CS eml_filename, O_RDONLY)) < 0)
1641 {
1642 int err = errno;
1643 return m_panic_defer_3(scanent, NULL,
1644 string_sprintf("can't open spool file %s: %s",
1645 eml_filename, strerror(err)),
1646 malware_daemon_ctx.sock);
1647 }
1648 if ((fsize = lseek(clam_fd, 0, SEEK_END)) < 0)
1649 {
1650 int err;
1651 b_seek: err = errno;
1652 (void)close(clam_fd);
1653 return m_panic_defer_3(scanent, NULL,
1654 string_sprintf("can't seek spool file %s: %s",
1655 eml_filename, strerror(err)),
1656 malware_daemon_ctx.sock);
1657 }
1658 fsize_uint = (unsigned int) fsize;
1659 if ((off_t)fsize_uint != fsize)
1660 {
1661 (void)close(clam_fd);
1662 return m_panic_defer_3(scanent, NULL,
1663 string_sprintf("seeking spool file %s, size overflow",
1664 eml_filename),
1665 malware_daemon_ctx.sock);
1666 }
1667 if (lseek(clam_fd, 0, SEEK_SET) < 0)
1668 goto b_seek;
1669
1670 if (!(clamav_fbuf = US malloc(fsize_uint)))
1671 {
1672 (void)close(clam_fd);
1673 return m_panic_defer_3(scanent, NULL,
1674 string_sprintf("unable to allocate memory %u for file (%s)",
1675 fsize_uint, eml_filename),
1676 malware_daemon_ctx.sock);
1677 }
1678
1679 if ((result = read(clam_fd, clamav_fbuf, fsize_uint)) < 0)
1680 {
1681 int err = errno;
1682 free(clamav_fbuf); (void)close(clam_fd);
1683 return m_panic_defer_3(scanent, NULL,
1684 string_sprintf("can't read spool file %s: %s",
1685 eml_filename, strerror(err)),
1686 malware_daemon_ctx.sock);
1687 }
1688 (void)close(clam_fd);
1689
1690 /* send file body to socket */
1691 send_size = htonl(fsize_uint);
1692 send_final_zeroblock = 0;
1693 if ((send(malware_daemon_ctx.sock, &send_size, sizeof(send_size), 0) < 0) ||
1694 (send(malware_daemon_ctx.sock, clamav_fbuf, fsize_uint, 0) < 0) ||
1695 (send(malware_daemon_ctx.sock, &send_final_zeroblock, sizeof(send_final_zeroblock), 0) < 0))
1696 {
1697 free(clamav_fbuf);
1698 return m_panic_defer_3(scanent, NULL,
1699 string_sprintf("unable to send file body to socket (%s)", hostname),
1700 malware_daemon_ctx.sock);
1701 }
1702
1703 free(clamav_fbuf);
1704 }
1705 else
1706 { /* use scan command */
1707 /* Send a SCAN command pointing to a filename; then in the then in the
1708 * scan-method-neutral part, read the response back */
1709
1710 /* ================================================================= */
1711
1712 /* Prior to the reworking post-Exim-4.72, this scanned a directory,
1713 which dates to when ClamAV needed us to break apart the email into the
1714 MIME parts (eg, with the now deprecated demime condition coming first).
1715 Some time back, ClamAV gained the ability to deconstruct the emails, so
1716 doing this would actually have resulted in the mail attachments being
1717 scanned twice, in the broken out files and from the original .eml.
1718 Since ClamAV now handles emails (and has for quite some time) we can
1719 just use the email file itself. */
1720 /* Pass the string to ClamAV (7 = "SCAN \n" + \0), if not already sent */
1721
1722 DEBUG(D_acl) debug_printf_indent(
1723 "Malware scan: issuing %s local-path scan [%s]\n",
1724 scanner_name, scanner_options);
1725
1726 if (cmd_str.len)
1727 if (send(malware_daemon_ctx.sock, cmd_str.data, cmd_str.len, 0) < 0)
1728 return m_panic_defer_3(scanent, CUS callout_address,
1729 string_sprintf("unable to write to socket (%s)", strerror(errno)),
1730 malware_daemon_ctx.sock);
1731
1732 /* Do not shut down the socket for writing; a user report noted that
1733 * clamd 0.70 does not react well to this. */
1734 }
1735 /* Commands have been sent, no matter which scan method or connection
1736 * type we're using; now just read the result, independent of method. */
1737
1738 /* Read the result */
1739 memset(av_buffer, 0, sizeof(av_buffer));
1740 bread = ip_recv(&malware_daemon_ctx, av_buffer, sizeof(av_buffer), tmo-time(NULL));
1741 (void)close(malware_daemon_ctx.sock);
1742 malware_daemon_ctx.sock = -1;
1743 malware_daemon_ctx.tls_ctx = NULL;
1744
1745 if (bread <= 0)
1746 return m_panic_defer(scanent, CUS callout_address,
1747 string_sprintf("unable to read from socket (%s)",
1748 errno == 0 ? "EOF" : strerror(errno)));
1749
1750 if (bread == sizeof(av_buffer))
1751 return m_panic_defer(scanent, CUS callout_address,
1752 US"buffer too small");
1753 /* We're now assured of a NULL at the end of av_buffer */
1754
1755 /* Check the result. ClamAV returns one of two result formats.
1756 In the basic mode, the response is of the form:
1757 infected: -> "<filename>: <virusname> FOUND"
1758 not-infected: -> "<filename>: OK"
1759 error: -> "<filename>: <errcode> ERROR
1760 If the ExtendedDetectionInfo option has been turned on, then we get:
1761 "<filename>: <virusname>(<virushash>:<virussize>) FOUND"
1762 for the infected case. Compare:
1763 /tmp/eicar.com: Eicar-Test-Signature FOUND
1764 /tmp/eicar.com: Eicar-Test-Signature(44d88612fea8a8f36de82e1278abb02f:68) FOUND
1765
1766 In the streaming case, clamd uses the filename "stream" which you should
1767 be able to verify with { ktrace clamdscan --stream /tmp/eicar.com }. (The
1768 client app will replace "stream" with the original filename before returning
1769 results to stdout, but the trace shows the data).
1770
1771 We will assume that the pathname passed to clamd from Exim does not contain
1772 a colon. We will have whined loudly above if the eml_filename does (and we're
1773 passing a filename to clamd). */
1774
1775 if (!(*av_buffer))
1776 return m_panic_defer(scanent, CUS callout_address,
1777 US"ClamAV returned null");
1778
1779 /* strip newline at the end (won't be present for zINSTREAM)
1780 (also any trailing whitespace, which shouldn't exist, but we depend upon
1781 this below, so double-check) */
1782 p = av_buffer + Ustrlen(av_buffer) - 1;
1783 if (*p == '\n') *p = '\0';
1784
1785 DEBUG(D_acl) debug_printf_indent("Malware response: %s\n", av_buffer);
1786
1787 while (isspace(*--p) && (p > av_buffer))
1788 *p = '\0';
1789 if (*p) ++p;
1790
1791 /* colon in returned output? */
1792 if(!(p = Ustrchr(av_buffer,':')))
1793 return m_panic_defer(scanent, CUS callout_address, string_sprintf(
1794 "ClamAV returned malformed result (missing colon): %s",
1795 av_buffer));
1796
1797 /* strip filename */
1798 while (*p && isspace(*++p)) /**/;
1799 vname = p;
1800
1801 /* It would be bad to encounter a virus with "FOUND" in part of the name,
1802 but we should at least be resistant to it. */
1803 p = Ustrrchr(vname, ' ');
1804 result_tag = p ? p+1 : vname;
1805
1806 if (Ustrcmp(result_tag, "FOUND") == 0)
1807 {
1808 /* p should still be the whitespace before the result_tag */
1809 while (isspace(*p)) --p;
1810 *++p = '\0';
1811 /* Strip off the extended information too, which will be in parens
1812 after the virus name, with no intervening whitespace. */
1813 if (*--p == ')')
1814 {
1815 /* "(hash:size)", so previous '(' will do; if not found, we have
1816 a curious virus name, but not an error. */
1817 p = Ustrrchr(vname, '(');
1818 if (p)
1819 *p = '\0';
1820 }
1821 malware_name = string_copy(vname);
1822 DEBUG(D_acl) debug_printf_indent("Malware found, name \"%s\"\n", malware_name);
1823
1824 }
1825 else if (Ustrcmp(result_tag, "ERROR") == 0)
1826 return m_panic_defer(scanent, CUS callout_address,
1827 string_sprintf("ClamAV returned: %s", av_buffer));
1828
1829 else if (Ustrcmp(result_tag, "OK") == 0)
1830 {
1831 /* Everything should be OK */
1832 malware_name = NULL;
1833 DEBUG(D_acl) debug_printf_indent("Malware not found\n");
1834
1835 }
1836 else
1837 return m_panic_defer(scanent, CUS callout_address,
1838 string_sprintf("unparseable response from ClamAV: {%s}", av_buffer));
1839
1840 break;
1841 } /* clamd */
1842 #endif
1843
1844 #ifndef DISABLE_MAL_SOCK
1845 case M_SOCK: /* "sock" scanner type ------------------------------------- */
1846 /* This code was derived by Martin Poole from the clamd code contributed
1847 by David Saez and the cmdline code
1848 */
1849 {
1850 int bread;
1851 uschar * commandline;
1852 uschar av_buffer[1024];
1853 uschar * linebuffer;
1854 uschar * sockline_scanner;
1855 uschar sockline_scanner_default[] = "%s\n";
1856 const pcre *sockline_trig_re;
1857 const pcre *sockline_name_re;
1858
1859 /* find scanner command line */
1860 if ( (sockline_scanner = string_nextinlist(&av_scanner_work, &sep,
1861 NULL, 0))
1862 && *sockline_scanner
1863 )
1864 { /* check for no expansions apart from one %s */
1865 uschar * s = Ustrchr(sockline_scanner, '%');
1866 if (s++)
1867 if ((*s != 's' && *s != '%') || Ustrchr(s+1, '%'))
1868 return m_panic_defer_3(scanent, NULL,
1869 US"unsafe sock scanner call spec", malware_daemon_ctx.sock);
1870 }
1871 else
1872 sockline_scanner = sockline_scanner_default;
1873 DEBUG(D_acl) debug_printf_indent("%15s%10s'%s'\n", "", "cmdline: ",
1874 string_printing(sockline_scanner));
1875
1876 /* find scanner output trigger */
1877 sockline_trig_re = m_pcre_nextinlist(&av_scanner_work, &sep,
1878 "missing trigger specification", &errstr);
1879 if (!sockline_trig_re)
1880 return m_panic_defer_3(scanent, NULL, errstr, malware_daemon_ctx.sock);
1881
1882 /* find virus name regex */
1883 sockline_name_re = m_pcre_nextinlist(&av_scanner_work, &sep,
1884 "missing virus name regex specification", &errstr);
1885 if (!sockline_name_re)
1886 return m_panic_defer_3(scanent, NULL, errstr, malware_daemon_ctx.sock);
1887
1888 /* prepare scanner call - security depends on expansions check above */
1889 commandline = string_sprintf( CS sockline_scanner, CS eml_filename);
1890 DEBUG(D_acl) debug_printf_indent("%15s%10s'%s'\n", "", "expanded: ",
1891 string_printing(commandline));
1892
1893 /* Pass the command string to the socket */
1894 if (m_sock_send(malware_daemon_ctx.sock, commandline, Ustrlen(commandline), &errstr) < 0)
1895 return m_panic_defer(scanent, CUS callout_address, errstr);
1896
1897 /* Read the result */
1898 bread = ip_recv(&malware_daemon_ctx, av_buffer, sizeof(av_buffer), tmo-time(NULL));
1899
1900 if (bread <= 0)
1901 return m_panic_defer_3(scanent, CUS callout_address,
1902 string_sprintf("unable to read from socket (%s)", strerror(errno)),
1903 malware_daemon_ctx.sock);
1904
1905 if (bread == sizeof(av_buffer))
1906 return m_panic_defer_3(scanent, CUS callout_address,
1907 US"buffer too small", malware_daemon_ctx.sock);
1908 av_buffer[bread] = '\0';
1909 linebuffer = string_copy(av_buffer);
1910 DEBUG(D_acl) debug_printf_indent("%15s%10s'%s'\n", "", "answer: ",
1911 string_printing(linebuffer));
1912
1913 /* try trigger match */
1914 if (regex_match_and_setup(sockline_trig_re, linebuffer, 0, -1))
1915 {
1916 if (!(malware_name = m_pcre_exec(sockline_name_re, av_buffer)))
1917 malware_name = US "unknown";
1918 DEBUG(D_acl) debug_printf_indent("%15s%10s'%s'\n", "", "name: ",
1919 string_printing(malware_name));
1920 }
1921 else /* no virus found */
1922 malware_name = NULL;
1923 break;
1924 }
1925 #endif
1926
1927 #ifndef DISABLE_MAL_MKS
1928 case M_MKSD: /* "mksd" scanner type ------------------------------------- */
1929 {
1930 char *mksd_options_end;
1931 int mksd_maxproc = 1; /* default, if no option supplied */
1932 int retval;
1933
1934 if (scanner_options)
1935 {
1936 mksd_maxproc = (int)strtol(CS scanner_options, &mksd_options_end, 10);
1937 if ( *scanner_options == '\0'
1938 || *mksd_options_end != '\0'
1939 || mksd_maxproc < 1
1940 || mksd_maxproc > 32
1941 )
1942 return m_panic_defer(scanent, CUS callout_address,
1943 string_sprintf("invalid option '%s'", scanner_options));
1944 }
1945
1946 if((malware_daemon_ctx.sock = ip_unixsocket(US "/var/run/mksd/socket", &errstr)) < 0)
1947 return m_panic_defer(scanent, CUS callout_address, errstr);
1948
1949 malware_name = NULL;
1950
1951 DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s scan\n", scanner_name);
1952
1953 if ((retval = mksd_scan_packed(scanent, malware_daemon_ctx.sock, eml_filename, tmo)) != OK)
1954 {
1955 close (malware_daemon_ctx.sock);
1956 return retval;
1957 }
1958 break;
1959 }
1960 #endif
1961
1962 #ifndef DISABLE_MAL_AVAST
1963 case M_AVAST: /* "avast" scanner type ----------------------------------- */
1964 {
1965 uschar buf[1024];
1966 uschar * scanrequest;
1967 enum {AVA_HELO, AVA_OPT, AVA_RSP, AVA_DONE} avast_stage;
1968 int nread;
1969 uschar * error_message = NULL;
1970 BOOL more_data = FALSE;
1971 BOOL strict = TRUE;
1972
1973 /* According to Martin Tuma @avast the protocol uses "escaped
1974 whitespace", that is, every embedded whitespace is backslash
1975 escaped, as well as backslash is protected by backslash.
1976 The returned lines contain the name of the scanned file, a tab
1977 and the [ ] marker.
1978 [+] - not infected
1979 [L] - infected
1980 [E] - some error occured
1981 Such marker follows the first non-escaped TAB. For more information
1982 see avast-protocol(5)
1983
1984 We observed two cases:
1985 -> SCAN /file
1986 <- /file [E]0.0 Error 13 Permission denied
1987 <- 451 SCAN Engine error 13 permission denied
1988
1989 -> SCAN /file
1990 <- /file… [E]3.0 Error 41120 The file is a decompression bomb
1991 <- /file… [+]2.0
1992 <- /file… [+]2.0 0 Eicar Test Virus!!!
1993 <- 200 SCAN OK
1994
1995 If the scanner returns 4xx, DEFER is a good decision, combined
1996 with a panic log entry, to get the admin's attention.
1997
1998 If the scanner returns 200, we reject it as malware, if found any,
1999 or, in case of an error, we set the malware message to the error
2000 string.
2001
2002 Some of the >= 42000 errors are message related - usually some
2003 broken archives etc, but some of them are e.g. license related.
2004 Once the license expires the engine starts returning errors for
2005 every scanning attempt. I¹ have the full list of the error codes
2006 but it is not a public API and is subject to change. It is hard
2007 for me to say what you should do in case of an engine error. You
2008 can have a “Treat * unscanned file as infection” policy or “Treat
2009 unscanned file as clean” policy. ¹) Jakub Bednar
2010
2011 */
2012
2013 if ( ( !ava_re_clean
2014 && !(ava_re_clean = m_pcre_compile(ava_re_clean_str, &errstr)))
2015 || ( !ava_re_virus
2016 && !(ava_re_virus = m_pcre_compile(ava_re_virus_str, &errstr)))
2017 || ( !ava_re_error
2018 && !(ava_re_error = m_pcre_compile(ava_re_error_str, &errstr)))
2019 )
2020 return malware_panic_defer(errstr);
2021
2022 /* wait for result */
2023 for (avast_stage = AVA_HELO;
2024 (nread = recv_line(malware_daemon_ctx.sock, buf, sizeof(buf), tmo)) > 0;
2025 )
2026 {
2027 int slen = Ustrlen(buf);
2028 if (slen >= 1)
2029 {
2030
2031 /* Multi line responses are bracketed between 210 … and nnn … */
2032 if (Ustrncmp(buf, "210", 3) == 0)
2033 {
2034 more_data = 1;
2035 continue;
2036 }
2037 else if (more_data && isdigit(buf[0])) more_data = 0;
2038
2039 switch (avast_stage)
2040 {
2041 case AVA_HELO:
2042 if (more_data) continue;
2043 if (Ustrncmp(buf, "220", 3) != 0)
2044 goto endloop; /* require a 220 */
2045 goto sendreq;
2046
2047 case AVA_OPT:
2048 if (more_data) continue;
2049 if (Ustrncmp(buf, "200", 3) != 0)
2050 goto endloop; /* require a 200 */
2051
2052 sendreq:
2053 {
2054 int len;
2055 /* Check for another option to send. Newline-terminate it. */
2056 if ((scanrequest = string_nextinlist(&av_scanner_work, &sep,
2057 NULL, 0)))
2058 {
2059 if (Ustrcmp(scanrequest, "pass_unscanned") == 0)
2060 {
2061 DEBUG(D_acl) debug_printf_indent("pass unscanned files as clean\n");
2062 strict = FALSE;
2063 goto sendreq;
2064 }
2065 scanrequest = string_sprintf("%s\n", scanrequest);
2066 avast_stage = AVA_OPT; /* just sent option */
2067 DEBUG(D_acl) debug_printf_indent("send to avast OPTION: %s", scanrequest);
2068 }
2069 else
2070 {
2071 scanrequest = string_sprintf("SCAN %s\n", eml_dir);
2072 avast_stage = AVA_RSP; /* just sent command */
2073 DEBUG(D_acl) debug_printf_indent("send to avast REQUEST: SCAN %s\n", eml_dir);
2074 }
2075
2076 /* send config-cmd or scan-request to socket */
2077 len = Ustrlen(scanrequest);
2078 if (send(malware_daemon_ctx.sock, scanrequest, len, 0) == -1)
2079 {
2080 scanrequest[len-1] = '\0';
2081 return m_panic_defer_3(scanent, CUS callout_address, string_sprintf(
2082 "unable to send request '%s' to socket (%s): %s",
2083 scanrequest, scanner_options, strerror(errno)), malware_daemon_ctx.sock);
2084 }
2085 break;
2086 }
2087
2088 case AVA_RSP:
2089
2090 if (isdigit(buf[0])) /* We're done */
2091 goto endloop;
2092
2093 if (malware_name) /* Nothing else matters, just read on */
2094 break;
2095
2096 if (pcre_exec(ava_re_clean, NULL, CS buf, slen, 0, 0, NULL, 0) == 0)
2097 break;
2098
2099 if ((malware_name = m_pcre_exec(ava_re_virus, buf)))
2100 {
2101 unescape(malware_name);
2102 DEBUG(D_acl)
2103 debug_printf_indent("unescaped malware name: '%s'\n", malware_name);
2104 break;
2105 }
2106
2107 if (strict) /* treat scanner errors as malware */
2108 {
2109 if ((malware_name = m_pcre_exec(ava_re_error, buf)))
2110 {
2111 unescape(malware_name);
2112 DEBUG(D_acl)
2113 debug_printf_indent("unescaped error message: '%s'\n", malware_name);
2114 break;
2115 }
2116 }
2117 else if (pcre_exec(ava_re_error, NULL, CS buf, slen, 0, 0, NULL, 0) == 0)
2118 {
2119 log_write(0, LOG_MAIN, "internal scanner error (ignored): %s", buf);
2120 break;
2121 }
2122
2123 /* here also for any unexpected response from the scanner */
2124 DEBUG(D_acl) debug_printf("avast response not handled: '%s'\n", buf);
2125
2126 goto endloop;
2127
2128 default: log_write(0, LOG_PANIC, "%s:%d:%s: should not happen",
2129 __FILE__, __LINE__, __FUNCTION__);
2130 }
2131 }
2132 }
2133
2134 endloop:
2135
2136 if (nread == -1) error_message = US"EOF from scanner";
2137 else if (nread < 0) error_message = US"timeout from scanner";
2138 else if (nread == 0) error_message = US"got nothing from scanner";
2139 else if (buf[0] != '2') error_message = buf;
2140
2141 DEBUG(D_acl) debug_printf_indent("sent to avast QUIT\n");
2142 if (send(malware_daemon_ctx.sock, "QUIT\n", 5, 0) == -1)
2143 return m_panic_defer_3(scanent, CUS callout_address,
2144 string_sprintf("unable to send quit request to socket (%s): %s",
2145 scanner_options, strerror(errno)), malware_daemon_ctx.sock);
2146
2147 if (error_message)
2148 return m_panic_defer_3(scanent, CUS callout_address, error_message, malware_daemon_ctx.sock);
2149
2150 }
2151 #endif
2152 } /* scanner type switch */
2153
2154 if (malware_daemon_ctx.sock >= 0)
2155 (void) close (malware_daemon_ctx.sock);
2156 malware_ok = TRUE; /* set "been here, done that" marker */
2157 }
2158
2159 /* match virus name against pattern (caseless ------->----------v) */
2160 if (malware_name && regex_match_and_setup(re, malware_name, 0, -1))
2161 {
2162 DEBUG(D_acl) debug_printf_indent(
2163 "Matched regex to malware [%s] [%s]\n", malware_re, malware_name);
2164 return OK;
2165 }
2166 else
2167 return FAIL;
2168 }
2169
2170
2171 /*************************************************
2172 * Scan an email for malware *
2173 *************************************************/
2174
2175 /* This is the normal interface for scanning an email, which doesn't need a
2176 filename; it's a wrapper around the malware_file function.
2177
2178 Arguments:
2179 malware_re match condition for "malware="
2180 timeout if nonzero, timeout in seconds
2181
2182 Returns: Exim message processing code (OK, FAIL, DEFER, ...)
2183 where true means malware was found (condition applies)
2184 */
2185 int
2186 malware(const uschar * malware_re, int timeout)
2187 {
2188 int ret = malware_internal(malware_re, NULL, timeout);
2189
2190 if (ret == DEFER) av_failed = TRUE;
2191 return ret;
2192 }
2193
2194
2195 /*************************************************
2196 * Scan a file for malware *
2197 *************************************************/
2198
2199 /* This is a test wrapper for scanning an email, which is not used in
2200 normal processing. Scan any file, using the Exim scanning interface.
2201 This function tampers with various global variables so is unsafe to use
2202 in any other context.
2203
2204 Arguments:
2205 eml_filename a file holding the message to be scanned
2206
2207 Returns: Exim message processing code (OK, FAIL, DEFER, ...)
2208 where true means malware was found (condition applies)
2209 */
2210 int
2211 malware_in_file(uschar *eml_filename)
2212 {
2213 uschar message_id_buf[64];
2214 int ret;
2215
2216 /* spool_mbox() assumes various parameters exist, when creating
2217 the relevant directory and the email within */
2218
2219 (void) string_format(message_id_buf, sizeof(message_id_buf),
2220 "dummy-%d", vaguely_random_number(INT_MAX));
2221 message_id = message_id_buf;
2222 sender_address = US"malware-sender@example.net";
2223 return_path = US"";
2224 recipients_list = NULL;
2225 receive_add_recipient(US"malware-victim@example.net", -1);
2226 f.enable_dollar_recipients = TRUE;
2227
2228 ret = malware_internal(US"*", eml_filename, 0);
2229
2230 Ustrncpy(spooled_message_id, message_id, sizeof(spooled_message_id));
2231 spool_mbox_ok = 1;
2232
2233 /* don't set no_mbox_unspool; at present, there's no way for it to become
2234 set, but if that changes, then it should apply to these tests too */
2235
2236 unspool_mbox();
2237
2238 /* silence static analysis tools */
2239 message_id = NULL;
2240
2241 return ret;
2242 }
2243
2244
2245 void
2246 malware_init(void)
2247 {
2248 if (!malware_default_re)
2249 malware_default_re = regex_must_compile(malware_regex_default, FALSE, TRUE);
2250
2251 #ifndef DISABLE_MAL_DRWEB
2252 if (!drweb_re)
2253 drweb_re = regex_must_compile(drweb_re_str, FALSE, TRUE);
2254 #endif
2255 #ifndef DISABLE_MAL_FSECURE
2256 if (!fsec_re)
2257 fsec_re = regex_must_compile(fsec_re_str, FALSE, TRUE);
2258 #endif
2259 #ifndef DISABLE_MAL_KAV
2260 if (!kav_re_sus)
2261 kav_re_sus = regex_must_compile(kav_re_sus_str, FALSE, TRUE);
2262 if (!kav_re_inf)
2263 kav_re_inf = regex_must_compile(kav_re_inf_str, FALSE, TRUE);
2264 #endif
2265 #ifndef DISABLE_MAL_AVAST
2266 if (!ava_re_clean)
2267 ava_re_clean = regex_must_compile(ava_re_clean_str, FALSE, TRUE);
2268 if (!ava_re_virus)
2269 ava_re_virus = regex_must_compile(ava_re_virus_str, FALSE, TRUE);
2270 if (!ava_re_error)
2271 ava_re_error = regex_must_compile(ava_re_error_str, FALSE, TRUE);
2272 #endif
2273 #ifndef DISABLE_MAL_FFROT6D
2274 if (!fprot6d_re_error)
2275 fprot6d_re_error = regex_must_compile(fprot6d_re_error_str, FALSE, TRUE);
2276 if (!fprot6d_re_virus)
2277 fprot6d_re_virus = regex_must_compile(fprot6d_re_virus_str, FALSE, TRUE);
2278 #endif
2279 }
2280
2281
2282 void
2283 malware_show_supported(FILE * f)
2284 {
2285 struct scan * sc;
2286 fprintf(f, "Malware:");
2287 for (sc = m_scans; sc->scancode != (scanner_t)-1; sc++) fprintf(f, " %s", sc->name);
2288 fprintf(f, "\n");
2289 }
2290
2291
2292 # endif /*!MACRO_PREDEF*/
2293 #endif /*WITH_CONTENT_SCAN*/
2294 /*
2295 * vi: aw ai sw=2
2296 */