Use C99 initialisations for iterators
[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 } scanner_t;
53 typedef enum {MC_NONE, MC_TCP, MC_UNIX, MC_STRM} contype_t;
54 static struct scan
55 {
56 scanner_t scancode;
57 const uschar * name;
58 const uschar * options_default;
59 contype_t conn;
60 } m_scans[] =
61 {
62 #ifndef DISABLE_MAL_FFROTD
63 { M_FPROTD, US"f-protd", US"localhost 10200-10204", MC_TCP },
64 #endif
65 #ifndef DISABLE_MAL_FFROT6D
66 { M_FPROT6D, US"f-prot6d", US"localhost 10200", MC_TCP },
67 #endif
68 #ifndef DISABLE_MAL_DRWEB
69 { M_DRWEB, US"drweb", US"/usr/local/drweb/run/drwebd.sock", MC_STRM },
70 #endif
71 #ifndef DISABLE_MAL_AVE
72 { M_AVES, US"aveserver", US"/var/run/aveserver", MC_UNIX },
73 #endif
74 #ifndef DISABLE_MAL_FSECURE
75 { M_FSEC, US"fsecure", US"/var/run/.fsav", MC_UNIX },
76 #endif
77 #ifndef DISABLE_MAL_KAV
78 { M_KAVD, US"kavdaemon", US"/var/run/AvpCtl", MC_UNIX },
79 #endif
80 #ifndef DISABLE_MAL_SOPHIE
81 { M_SOPHIE, US"sophie", US"/var/run/sophie", MC_UNIX },
82 #endif
83 #ifndef DISABLE_MAL_CLAM
84 { M_CLAMD, US"clamd", US"/tmp/clamd", MC_NONE },
85 #endif
86 #ifndef DISABLE_MAL_MKS
87 { M_MKSD, US"mksd", NULL, MC_NONE },
88 #endif
89 #ifndef DISABLE_MAL_AVAST
90 { M_AVAST, US"avast", US"/var/run/avast/scan.sock", MC_STRM },
91 #endif
92 #ifndef DISABLE_MAL_SOCK
93 { M_SOCK, US"sock", US"/tmp/malware.sock", MC_STRM },
94 #endif
95 #ifndef DISABLE_MAL_CMDLINE
96 { M_CMDL, US"cmdline", NULL, MC_NONE },
97 #endif
98 { -1, NULL, NULL, MC_NONE } /* end-marker */
99 };
100
101 /******************************************************************************/
102 # ifdef MACRO_PREDEF /* build solely to predefine macros */
103
104 # include "macro_predef.h"
105
106 void
107 features_malware(void)
108 {
109 const uschar * s;
110 uschar * t;
111 uschar buf[64];
112
113 spf(buf, sizeof(buf), US"_HAVE_MALWARE_");
114
115 for (const struct scan * sc = m_scans; sc->scancode != -1; sc++)
116 {
117 for (s = sc->name, t = buf+14; *s; s++) if (*s != '-')
118 *t++ = toupper(*s);
119 *t = '\0';
120 builtin_macro_create(buf);
121 }
122 }
123
124 /******************************************************************************/
125 # else /*!MACRO_PREDEF, main build*/
126
127
128 #define MALWARE_TIMEOUT 120 /* default timeout, seconds */
129
130 static const uschar * malware_regex_default = US ".+";
131 static const pcre * malware_default_re = NULL;
132
133
134
135 #ifndef DISABLE_MAL_CLAM
136 /* The maximum number of clamd servers that are supported in the configuration */
137 # define MAX_CLAMD_SERVERS 32
138 # define MAX_CLAMD_SERVERS_S "32"
139
140 typedef struct clamd_address {
141 uschar * hostspec;
142 unsigned tcp_port;
143 unsigned retry;
144 } clamd_address;
145 #endif
146
147
148 #ifndef DISABLE_MAL_DRWEB
149 # define DRWEBD_SCAN_CMD (1) /* scan file, buffer or diskfile */
150 # define DRWEBD_RETURN_VIRUSES (1<<0) /* ask daemon return to us viruses names from report */
151 # define DRWEBD_IS_MAIL (1<<19) /* say to daemon that format is "archive MAIL" */
152
153 # define DERR_READ_ERR (1<<0) /* read error */
154 # define DERR_NOMEMORY (1<<2) /* no memory */
155 # define DERR_TIMEOUT (1<<9) /* scan timeout has run out */
156 # define DERR_BAD_CALL (1<<15) /* wrong command */
157
158 static const uschar * drweb_re_str = US "infected\\swith\\s*(.+?)$";
159 static const pcre * drweb_re = NULL;
160 #endif
161
162 #ifndef DISABLE_MAL_FSECURE
163 static const uschar * fsec_re_str = US "\\S{0,5}INFECTED\\t[^\\t]*\\t([^\\t]+)\\t\\S*$";
164 static const pcre * fsec_re = NULL;
165 #endif
166
167 #ifndef DISABLE_MAL_KAV
168 static const uschar * kav_re_sus_str = US "suspicion:\\s*(.+?)\\s*$";
169 static const uschar * kav_re_inf_str = US "infected:\\s*(.+?)\\s*$";
170 static const pcre * kav_re_sus = NULL;
171 static const pcre * kav_re_inf = NULL;
172 #endif
173
174 #ifndef DISABLE_MAL_AVAST
175 static const uschar * ava_re_clean_str = US "(?!\\\\)\\t\\[\\+\\]";
176 static const uschar * ava_re_virus_str = US "(?!\\\\)\\t\\[L\\]\\d+\\.0\\t0\\s(.*)";
177 static const uschar * ava_re_error_str = US "(?!\\\\)\\t\\[E\\]\\d+\\.0\\tError\\s\\d+\\s(.*)";
178 static const pcre * ava_re_clean = NULL;
179 static const pcre * ava_re_virus = NULL;
180 static const pcre * ava_re_error = NULL;
181 #endif
182
183 #ifndef DISABLE_MAL_FFROT6D
184 static const uschar * fprot6d_re_error_str = US "^\\d+\\s<(.+?)>$";
185 static const uschar * fprot6d_re_virus_str = US "^\\d+\\s<infected:\\s+(.+?)>\\s+.+$";
186 static const pcre * fprot6d_re_error = NULL;
187 static const pcre * fprot6d_re_virus = NULL;
188 #endif
189
190
191
192 /******************************************************************************/
193
194 #ifndef DISABLE_MAL_KAV
195 /* Routine to check whether a system is big- or little-endian.
196 Ripped from http://www.faqs.org/faqs/graphics/fileformats-faq/part4/section-7.html
197 Needed for proper kavdaemon implementation. Sigh. */
198 # define BIG_MY_ENDIAN 0
199 # define LITTLE_MY_ENDIAN 1
200 static int test_byte_order(void);
201 static inline int
202 test_byte_order()
203 {
204 short int word = 0x0001;
205 char *byte = CS &word;
206 return(byte[0] ? LITTLE_MY_ENDIAN : BIG_MY_ENDIAN);
207 }
208 #endif
209
210 BOOL malware_ok = FALSE;
211
212 /* Gross hacks for the -bmalware option; perhaps we should just create
213 the scan directory normally for that case, but look into rigging up the
214 needed header variables if not already set on the command-line? */
215 extern int spool_mbox_ok;
216 extern uschar spooled_message_id[MESSAGE_ID_LENGTH+1];
217
218
219 /* Some (currently avast only) use backslash escaped whitespace,
220 this function undoes these escapes */
221
222 static inline void
223 unescape(uschar *p)
224 {
225 uschar *p0;
226 for (; *p; ++p)
227 if (*p == '\\' && (isspace(p[1]) || p[1] == '\\'))
228 for (p0 = p; *p0; ++p0) *p0 = p0[1];
229 }
230
231 /* --- malware_*_defer --- */
232 static inline int
233 malware_panic_defer(const uschar * str)
234 {
235 log_write(0, LOG_MAIN|LOG_PANIC, "malware acl condition: %s", str);
236 return DEFER;
237 }
238 static inline int
239 malware_log_defer(const uschar * str)
240 {
241 log_write(0, LOG_MAIN, "malware acl condition: %s", str);
242 return DEFER;
243 }
244 /* --- m_*_defer --- */
245 static inline int
246 m_panic_defer(struct scan * scanent, const uschar * hostport,
247 const uschar * str)
248 {
249 return malware_panic_defer(string_sprintf("%s %s : %s",
250 scanent->name, hostport ? hostport : CUS"", str));
251 }
252 static inline int
253 m_log_defer(struct scan * scanent, const uschar * hostport,
254 const uschar * str)
255 {
256 return malware_log_defer(string_sprintf("%s %s : %s",
257 scanent->name, hostport ? hostport : CUS"", str));
258 }
259 /* --- m_*_defer_3 */
260 static inline int
261 m_panic_defer_3(struct scan * scanent, const uschar * hostport,
262 const uschar * str, int fd_to_close)
263 {
264 (void) close(fd_to_close);
265 return m_panic_defer(scanent, hostport, str);
266 }
267
268 /*************************************************/
269
270 #ifndef DISABLE_MAL_CLAM
271 /* Only used by the Clamav code, which is working from a list of servers and
272 uses the returned in_addr to get a second connection to the same system.
273 */
274 static inline int
275 m_tcpsocket(const uschar * hostname, unsigned int port,
276 host_item * host, uschar ** errstr, const blob * fastopen_blob)
277 {
278 return ip_connectedsocket(SOCK_STREAM, hostname, port, port, 5,
279 host, errstr, fastopen_blob);
280 }
281 #endif
282
283 static int
284 m_sock_send(int sock, uschar * buf, int cnt, uschar ** errstr)
285 {
286 if (send(sock, buf, cnt, 0) < 0)
287 {
288 int err = errno;
289 (void)close(sock);
290 *errstr = string_sprintf("unable to send to socket (%s): %s",
291 buf, strerror(err));
292 return -1;
293 }
294 return sock;
295 }
296
297 static const pcre *
298 m_pcre_compile(const uschar * re, uschar ** errstr)
299 {
300 const uschar * rerror;
301 int roffset;
302 const pcre * cre;
303
304 cre = pcre_compile(CS re, PCRE_COPT, (const char **)&rerror, &roffset, NULL);
305 if (!cre)
306 *errstr= string_sprintf("regular expression error in '%s': %s at offset %d",
307 re, rerror, roffset);
308 return cre;
309 }
310
311 uschar *
312 m_pcre_exec(const pcre * cre, uschar * text)
313 {
314 int ovector[10*3];
315 int i = pcre_exec(cre, NULL, CS text, Ustrlen(text), 0, 0,
316 ovector, nelem(ovector));
317 uschar * substr = NULL;
318 if (i >= 2) /* Got it */
319 pcre_get_substring(CS text, ovector, i, 1, (const char **) &substr);
320 return substr;
321 }
322
323 static const pcre *
324 m_pcre_nextinlist(const uschar ** list, int * sep,
325 char * listerr, uschar ** errstr)
326 {
327 const uschar * list_ele;
328 const pcre * cre = NULL;
329
330 if (!(list_ele = string_nextinlist(list, sep, NULL, 0)))
331 *errstr = US listerr;
332 else
333 {
334 DEBUG(D_acl) debug_printf_indent("%15s%10s'%s'\n", "", "RE: ",
335 string_printing(list_ele));
336 cre = m_pcre_compile(CUS list_ele, errstr);
337 }
338 return cre;
339 }
340
341 /*
342 Simple though inefficient wrapper for reading a line. Drop CRs and the
343 trailing newline. Can return early on buffer full. Null-terminate.
344 Apply initial timeout if no data ready.
345
346 Return: number of chars - zero for an empty line
347 -1 on EOF
348 -2 on timeout or error
349 */
350 static int
351 recv_line(int fd, uschar * buffer, int bsize, int tmo)
352 {
353 uschar * p = buffer;
354 ssize_t rcv;
355 BOOL ok = FALSE;
356
357 if (!fd_ready(fd, tmo-time(NULL)))
358 return -2;
359
360 /*XXX tmo handling assumes we always get a whole line */
361 /* read until \n */
362 errno = 0;
363 while ((rcv = read(fd, p, 1)) > 0)
364 {
365 ok = TRUE;
366 if (p-buffer > bsize-2) break;
367 if (*p == '\n') break;
368 if (*p != '\r') p++;
369 }
370 if (!ok)
371 {
372 DEBUG(D_acl) debug_printf_indent("Malware scan: read %s (%s)\n",
373 rcv==0 ? "EOF" : "error", strerror(errno));
374 return rcv==0 ? -1 : -2;
375 }
376 *p = '\0';
377
378 DEBUG(D_acl) debug_printf_indent("Malware scan: read '%s'\n", buffer);
379 return p - buffer;
380 }
381
382 /* return TRUE iff size as requested */
383 static BOOL
384 recv_len(int sock, void * buf, int size, int tmo)
385 {
386 return fd_ready(sock, tmo-time(NULL))
387 ? recv(sock, buf, size, 0) == size
388 : FALSE;
389 }
390
391
392
393 #ifndef DISABLE_MAL_MKS
394 /* ============= private routines for the "mksd" scanner type ============== */
395
396 # include <sys/uio.h>
397
398 static inline int
399 mksd_writev (int sock, struct iovec * iov, int iovcnt)
400 {
401 int i;
402
403 for (;;)
404 {
405 do
406 i = writev (sock, iov, iovcnt);
407 while (i < 0 && errno == EINTR);
408 if (i <= 0)
409 {
410 (void) malware_panic_defer(
411 US"unable to write to mksd UNIX socket (/var/run/mksd/socket)");
412 return -1;
413 }
414 for (;;) /* check for short write */
415 if (i >= iov->iov_len)
416 {
417 if (--iovcnt == 0)
418 return 0;
419 i -= iov->iov_len;
420 iov++;
421 }
422 else
423 {
424 iov->iov_len -= i;
425 iov->iov_base = CS iov->iov_base + i;
426 break;
427 }
428 }
429 }
430
431 static inline int
432 mksd_read_lines (int sock, uschar *av_buffer, int av_buffer_size, int tmo)
433 {
434 client_conn_ctx cctx = {.sock = sock};
435 int offset = 0;
436 int i;
437
438 do
439 {
440 i = ip_recv(&cctx, av_buffer+offset, av_buffer_size-offset, tmo-time(NULL));
441 if (i <= 0)
442 {
443 (void) malware_panic_defer(US"unable to read from mksd UNIX socket (/var/run/mksd/socket)");
444 return -1;
445 }
446
447 offset += i;
448 /* offset == av_buffer_size -> buffer full */
449 if (offset == av_buffer_size)
450 {
451 (void) malware_panic_defer(US"malformed reply received from mksd");
452 return -1;
453 }
454 } while (av_buffer[offset-1] != '\n');
455
456 av_buffer[offset] = '\0';
457 return offset;
458 }
459
460 static inline int
461 mksd_parse_line(struct scan * scanent, char * line)
462 {
463 char *p;
464
465 switch (*line)
466 {
467 case 'O': /* OK */
468 return OK;
469
470 case 'E':
471 case 'A': /* ERR */
472 if ((p = strchr (line, '\n')) != NULL)
473 *p = '\0';
474 return m_panic_defer(scanent, NULL,
475 string_sprintf("scanner failed: %s", line));
476
477 default: /* VIR */
478 if ((p = strchr (line, '\n')) != NULL)
479 {
480 *p = '\0';
481 if ( p-line > 5
482 && line[3] == ' '
483 && (p = strchr(line+4, ' ')) != NULL
484 && p-line > 4
485 )
486 {
487 *p = '\0';
488 malware_name = string_copy(US line+4);
489 return OK;
490 }
491 }
492 return m_panic_defer(scanent, NULL,
493 string_sprintf("malformed reply received: %s", line));
494 }
495 }
496
497 static int
498 mksd_scan_packed(struct scan * scanent, int sock, const uschar * scan_filename,
499 int tmo)
500 {
501 struct iovec iov[3];
502 const char *cmd = "MSQ\n";
503 uschar av_buffer[1024];
504
505 iov[0].iov_base = (void *) cmd;
506 iov[0].iov_len = 3;
507 iov[1].iov_base = (void *) scan_filename;
508 iov[1].iov_len = Ustrlen(scan_filename);
509 iov[2].iov_base = (void *) (cmd + 3);
510 iov[2].iov_len = 1;
511
512 if (mksd_writev (sock, iov, 3) < 0)
513 return DEFER;
514
515 if (mksd_read_lines (sock, av_buffer, sizeof (av_buffer), tmo) < 0)
516 return DEFER;
517
518 return mksd_parse_line (scanent, CS av_buffer);
519 }
520 #endif /* MKSD */
521
522
523 #ifndef DISABLE_MAL_CLAM
524 static int
525 clamd_option(clamd_address * cd, const uschar * optstr, int * subsep)
526 {
527 uschar * s;
528
529 cd->retry = 0;
530 while ((s = string_nextinlist(&optstr, subsep, NULL, 0)))
531 if (Ustrncmp(s, "retry=", 6) == 0)
532 {
533 int sec = readconf_readtime((s += 6), '\0', FALSE);
534 if (sec < 0)
535 return FAIL;
536 cd->retry = sec;
537 }
538 else
539 return FAIL;
540 return OK;
541 }
542 #endif
543
544
545
546 /*************************************************
547 * Scan content for malware *
548 *************************************************/
549
550 /* This is an internal interface for scanning an email; the normal interface
551 is via malware(), or there's malware_in_file() used for testing/debugging.
552
553 Arguments:
554 malware_re match condition for "malware="
555 scan_filename the file holding the email to be scanned, if we're faking
556 this up for the -bmalware test, else NULL
557 timeout if nonzero, non-default timeoutl
558
559 Returns: Exim message processing code (OK, FAIL, DEFER, ...)
560 where true means malware was found (condition applies)
561 */
562 static int
563 malware_internal(const uschar * malware_re, const uschar * scan_filename,
564 int timeout)
565 {
566 int sep = 0;
567 const uschar *av_scanner_work = av_scanner;
568 uschar *scanner_name;
569 unsigned long mbox_size;
570 FILE *mbox_file;
571 const pcre *re;
572 uschar * errstr;
573 struct scan * scanent;
574 const uschar * scanner_options;
575 client_conn_ctx malware_daemon_ctx = {.sock = -1};
576 time_t tmo;
577 uschar * eml_filename, * eml_dir;
578
579 if (!malware_re)
580 return FAIL; /* empty means "don't match anything" */
581
582 /* Ensure the eml mbox file is spooled up */
583
584 if (!(mbox_file = spool_mbox(&mbox_size, scan_filename, &eml_filename)))
585 return malware_panic_defer(US"error while creating mbox spool file");
586
587 /* None of our current scanners need the mbox file as a stream (they use
588 the name), so we can close it right away. Get the directory too. */
589
590 (void) fclose(mbox_file);
591 eml_dir = string_copyn(eml_filename, Ustrrchr(eml_filename, '/') - eml_filename);
592
593 /* parse 1st option */
594 if (strcmpic(malware_re, US"false") == 0 || Ustrcmp(malware_re,"0") == 0)
595 return FAIL; /* explicitly no matching */
596
597 /* special cases (match anything except empty) */
598 if ( strcmpic(malware_re,US"true") == 0
599 || Ustrcmp(malware_re,"*") == 0
600 || Ustrcmp(malware_re,"1") == 0
601 )
602 {
603 if ( !malware_default_re
604 && !(malware_default_re = m_pcre_compile(malware_regex_default, &errstr)))
605 return malware_panic_defer(errstr);
606 malware_re = malware_regex_default;
607 re = malware_default_re;
608 }
609
610 /* compile the regex, see if it works */
611 else if (!(re = m_pcre_compile(malware_re, &errstr)))
612 return malware_panic_defer(errstr);
613
614 /* if av_scanner starts with a dollar, expand it first */
615 if (*av_scanner == '$')
616 {
617 if (!(av_scanner_work = expand_string(av_scanner)))
618 return malware_panic_defer(
619 string_sprintf("av_scanner starts with $, but expansion failed: %s",
620 expand_string_message));
621
622 DEBUG(D_acl)
623 debug_printf_indent("Expanded av_scanner global: %s\n", av_scanner_work);
624 /* disable result caching in this case */
625 malware_name = NULL;
626 malware_ok = FALSE;
627 }
628
629 /* Do not scan twice (unless av_scanner is dynamic). */
630 if (!malware_ok)
631 {
632 /* find the scanner type from the av_scanner option */
633 if (!(scanner_name = string_nextinlist(&av_scanner_work, &sep, NULL, 0)))
634 return malware_panic_defer(US"av_scanner configuration variable is empty");
635 if (!timeout) timeout = MALWARE_TIMEOUT;
636 tmo = time(NULL) + timeout;
637
638 for (scanent = m_scans; ; scanent++)
639 {
640 if (!scanent->name)
641 return malware_panic_defer(string_sprintf("unknown scanner type '%s'",
642 scanner_name));
643 if (strcmpic(scanner_name, US scanent->name) != 0)
644 continue;
645 DEBUG(D_acl) debug_printf_indent("Malware scan: %s tmo=%s\n",
646 scanner_name, readconf_printtime(timeout));
647
648 if (!(scanner_options = string_nextinlist(&av_scanner_work, &sep, NULL, 0)))
649 scanner_options = scanent->options_default;
650 if (scanent->conn == MC_NONE)
651 break;
652
653 DEBUG(D_acl) debug_printf_indent("%15s%10s%s\n", "", "socket: ", scanner_options);
654 switch(scanent->conn)
655 {
656 case MC_TCP:
657 malware_daemon_ctx.sock = ip_tcpsocket(scanner_options, &errstr, 5); break;
658 case MC_UNIX:
659 malware_daemon_ctx.sock = ip_unixsocket(scanner_options, &errstr); break;
660 case MC_STRM:
661 malware_daemon_ctx.sock = ip_streamsocket(scanner_options, &errstr, 5); break;
662 default:
663 /* compiler quietening */ break;
664 }
665 if (malware_daemon_ctx.sock < 0)
666 return m_panic_defer(scanent, CUS callout_address, errstr);
667 break;
668 }
669
670 switch (scanent->scancode)
671 {
672 #ifndef DISABLE_MAL_FFROTD
673 case M_FPROTD: /* "f-protd" scanner type -------------------------------- */
674 {
675 uschar *fp_scan_option;
676 unsigned int detected=0, par_count=0;
677 uschar * scanrequest;
678 uschar buf[32768], *strhelper, *strhelper2;
679 uschar * malware_name_internal = NULL;
680 int len;
681
682 scanrequest = string_sprintf("GET %s", eml_filename);
683
684 while ((fp_scan_option = string_nextinlist(&av_scanner_work, &sep,
685 NULL, 0)))
686 {
687 scanrequest = string_sprintf("%s%s%s", scanrequest,
688 par_count ? "%20" : "?", fp_scan_option);
689 par_count++;
690 }
691 scanrequest = string_sprintf("%s HTTP/1.0\r\n\r\n", scanrequest);
692 DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s: %s\n",
693 scanner_name, scanrequest);
694
695 /* send scan request */
696 if (m_sock_send(malware_daemon_ctx.sock, scanrequest, Ustrlen(scanrequest)+1, &errstr) < 0)
697 return m_panic_defer(scanent, CUS callout_address, errstr);
698
699 while ((len = recv_line(malware_daemon_ctx.sock, buf, sizeof(buf), tmo)) >= 0)
700 if (len > 0)
701 {
702 if (Ustrstr(buf, US"<detected type=\"") != NULL)
703 detected = 1;
704 else if (detected && (strhelper = Ustrstr(buf, US"<name>")))
705 {
706 if ((strhelper2 = Ustrstr(buf, US"</name>")) != NULL)
707 {
708 *strhelper2 = '\0';
709 malware_name_internal = string_copy(strhelper+6);
710 }
711 }
712 else if (Ustrstr(buf, US"<summary code=\""))
713 {
714 malware_name = Ustrstr(buf, US"<summary code=\"11\">")
715 ? malware_name_internal : NULL;
716 break;
717 }
718 }
719 if (len < -1)
720 {
721 (void)close(malware_daemon_ctx.sock);
722 return DEFER;
723 }
724 break;
725 } /* f-protd */
726 #endif
727
728 #ifndef DISABLE_MAL_FFROT6D
729 case M_FPROT6D: /* "f-prot6d" scanner type ----------------------------------- */
730 {
731 int bread;
732 uschar * e;
733 uschar * linebuffer;
734 uschar * scanrequest;
735 uschar av_buffer[1024];
736
737 if ((!fprot6d_re_virus && !(fprot6d_re_virus = m_pcre_compile(fprot6d_re_virus_str, &errstr)))
738 || (!fprot6d_re_error && !(fprot6d_re_error = m_pcre_compile(fprot6d_re_error_str, &errstr))))
739 return malware_panic_defer(errstr);
740
741 scanrequest = string_sprintf("SCAN FILE %s\n", eml_filename);
742 DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s: %s\n",
743 scanner_name, scanrequest);
744
745 if (m_sock_send(malware_daemon_ctx.sock, scanrequest, Ustrlen(scanrequest), &errstr) < 0)
746 return m_panic_defer(scanent, CUS callout_address, errstr);
747
748 bread = ip_recv(&malware_daemon_ctx, av_buffer, sizeof(av_buffer), tmo-time(NULL));
749
750 if (bread <= 0)
751 return m_panic_defer_3(scanent, CUS callout_address,
752 string_sprintf("unable to read from socket (%s)", strerror(errno)),
753 malware_daemon_ctx.sock);
754
755 if (bread == sizeof(av_buffer))
756 return m_panic_defer_3(scanent, CUS callout_address,
757 US"buffer too small", malware_daemon_ctx.sock);
758
759 av_buffer[bread] = '\0';
760 linebuffer = string_copy(av_buffer);
761
762 m_sock_send(malware_daemon_ctx.sock, US"QUIT\n", 5, 0);
763
764 if ((e = m_pcre_exec(fprot6d_re_error, linebuffer)))
765 return m_panic_defer_3(scanent, CUS callout_address,
766 string_sprintf("scanner reported error (%s)", e), malware_daemon_ctx.sock);
767
768 if (!(malware_name = m_pcre_exec(fprot6d_re_virus, linebuffer)))
769 malware_name = NULL;
770
771 break;
772 } /* f-prot6d */
773 #endif
774
775 #ifndef DISABLE_MAL_DRWEB
776 case M_DRWEB: /* "drweb" scanner type ----------------------------------- */
777 /* v0.1 - added support for tcp sockets */
778 /* v0.0 - initial release -- support for unix sockets */
779 {
780 int result;
781 off_t fsize;
782 unsigned int fsize_uint;
783 uschar * tmpbuf, *drweb_fbuf;
784 int drweb_rc, drweb_cmd, drweb_flags = 0x0000, drweb_fd,
785 drweb_vnum, drweb_slen, drweb_fin = 0x0000;
786
787 /* prepare variables */
788 drweb_cmd = htonl(DRWEBD_SCAN_CMD);
789 drweb_flags = htonl(DRWEBD_RETURN_VIRUSES | DRWEBD_IS_MAIL);
790
791 if (*scanner_options != '/')
792 {
793 /* calc file size */
794 if ((drweb_fd = open(CCS eml_filename, O_RDONLY)) == -1)
795 return m_panic_defer_3(scanent, NULL,
796 string_sprintf("can't open spool file %s: %s",
797 eml_filename, strerror(errno)),
798 malware_daemon_ctx.sock);
799
800 if ((fsize = lseek(drweb_fd, 0, SEEK_END)) == -1)
801 {
802 int err;
803 badseek: err = errno;
804 (void)close(drweb_fd);
805 return m_panic_defer_3(scanent, NULL,
806 string_sprintf("can't seek spool file %s: %s",
807 eml_filename, strerror(err)),
808 malware_daemon_ctx.sock);
809 }
810 fsize_uint = (unsigned int) fsize;
811 if ((off_t)fsize_uint != fsize)
812 {
813 (void)close(drweb_fd);
814 return m_panic_defer_3(scanent, NULL,
815 string_sprintf("seeking spool file %s, size overflow",
816 eml_filename),
817 malware_daemon_ctx.sock);
818 }
819 drweb_slen = htonl(fsize);
820 if (lseek(drweb_fd, 0, SEEK_SET) < 0)
821 goto badseek;
822
823 DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s remote scan [%s]\n",
824 scanner_name, scanner_options);
825
826 /* send scan request */
827 if ((send(malware_daemon_ctx.sock, &drweb_cmd, sizeof(drweb_cmd), 0) < 0) ||
828 (send(malware_daemon_ctx.sock, &drweb_flags, sizeof(drweb_flags), 0) < 0) ||
829 (send(malware_daemon_ctx.sock, &drweb_fin, sizeof(drweb_fin), 0) < 0) ||
830 (send(malware_daemon_ctx.sock, &drweb_slen, sizeof(drweb_slen), 0) < 0))
831 {
832 (void)close(drweb_fd);
833 return m_panic_defer_3(scanent, CUS callout_address, string_sprintf(
834 "unable to send commands to socket (%s)", scanner_options),
835 malware_daemon_ctx.sock);
836 }
837
838 if (!(drweb_fbuf = US malloc(fsize_uint)))
839 {
840 (void)close(drweb_fd);
841 return m_panic_defer_3(scanent, NULL,
842 string_sprintf("unable to allocate memory %u for file (%s)",
843 fsize_uint, eml_filename),
844 malware_daemon_ctx.sock);
845 }
846
847 if ((result = read (drweb_fd, drweb_fbuf, fsize)) == -1)
848 {
849 int err = errno;
850 (void)close(drweb_fd);
851 free(drweb_fbuf);
852 return m_panic_defer_3(scanent, NULL,
853 string_sprintf("can't read spool file %s: %s",
854 eml_filename, strerror(err)),
855 malware_daemon_ctx.sock);
856 }
857 (void)close(drweb_fd);
858
859 /* send file body to socket */
860 if (send(malware_daemon_ctx.sock, drweb_fbuf, fsize, 0) < 0)
861 {
862 free(drweb_fbuf);
863 return m_panic_defer_3(scanent, CUS callout_address, string_sprintf(
864 "unable to send file body to socket (%s)", scanner_options),
865 malware_daemon_ctx.sock);
866 }
867 }
868 else
869 {
870 drweb_slen = htonl(Ustrlen(eml_filename));
871
872 DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s local scan [%s]\n",
873 scanner_name, scanner_options);
874
875 /* send scan request */
876 if ((send(malware_daemon_ctx.sock, &drweb_cmd, sizeof(drweb_cmd), 0) < 0) ||
877 (send(malware_daemon_ctx.sock, &drweb_flags, sizeof(drweb_flags), 0) < 0) ||
878 (send(malware_daemon_ctx.sock, &drweb_slen, sizeof(drweb_slen), 0) < 0) ||
879 (send(malware_daemon_ctx.sock, eml_filename, Ustrlen(eml_filename), 0) < 0) ||
880 (send(malware_daemon_ctx.sock, &drweb_fin, sizeof(drweb_fin), 0) < 0))
881 return m_panic_defer_3(scanent, CUS callout_address, string_sprintf(
882 "unable to send commands to socket (%s)", scanner_options),
883 malware_daemon_ctx.sock);
884 }
885
886 /* wait for result */
887 if (!recv_len(malware_daemon_ctx.sock, &drweb_rc, sizeof(drweb_rc), tmo))
888 return m_panic_defer_3(scanent, CUS callout_address,
889 US"unable to read return code", malware_daemon_ctx.sock);
890 drweb_rc = ntohl(drweb_rc);
891
892 if (!recv_len(malware_daemon_ctx.sock, &drweb_vnum, sizeof(drweb_vnum), tmo))
893 return m_panic_defer_3(scanent, CUS callout_address,
894 US"unable to read the number of viruses", malware_daemon_ctx.sock);
895 drweb_vnum = ntohl(drweb_vnum);
896
897 /* "virus(es) found" if virus number is > 0 */
898 if (drweb_vnum)
899 {
900 gstring * g = NULL;
901
902 /* setup default virus name */
903 malware_name = US"unknown";
904
905 /* set up match regex */
906 if (!drweb_re)
907 drweb_re = m_pcre_compile(drweb_re_str, &errstr);
908
909 /* read and concatenate virus names into one string */
910 for (int i = 0; i < drweb_vnum; i++)
911 {
912 int ovector[10*3];
913
914 /* read the size of report */
915 if (!recv_len(malware_daemon_ctx.sock, &drweb_slen, sizeof(drweb_slen), tmo))
916 return m_panic_defer_3(scanent, CUS callout_address,
917 US"cannot read report size", malware_daemon_ctx.sock);
918 drweb_slen = ntohl(drweb_slen);
919 tmpbuf = store_get(drweb_slen);
920
921 /* read report body */
922 if (!recv_len(malware_daemon_ctx.sock, tmpbuf, drweb_slen, tmo))
923 return m_panic_defer_3(scanent, CUS callout_address,
924 US"cannot read report string", malware_daemon_ctx.sock);
925 tmpbuf[drweb_slen] = '\0';
926
927 /* try matcher on the line, grab substring */
928 result = pcre_exec(drweb_re, NULL, CS tmpbuf, Ustrlen(tmpbuf), 0, 0,
929 ovector, nelem(ovector));
930 if (result >= 2)
931 {
932 const char * pre_malware_nb;
933
934 pcre_get_substring(CS tmpbuf, ovector, result, 1, &pre_malware_nb);
935
936 if (i==0) /* the first name we just copy to malware_name */
937 g = string_cat(NULL, US pre_malware_nb);
938
939 /*XXX could be string_append_listele? */
940 else /* concatenate each new virus name to previous */
941 g = string_append(g, 2, "/", pre_malware_nb);
942
943 pcre_free_substring(pre_malware_nb);
944 }
945 }
946 malware_name = string_from_gstring(g);
947 }
948 else
949 {
950 const char *drweb_s = NULL;
951
952 if (drweb_rc & DERR_READ_ERR) drweb_s = "read error";
953 if (drweb_rc & DERR_NOMEMORY) drweb_s = "no memory";
954 if (drweb_rc & DERR_TIMEOUT) drweb_s = "timeout";
955 if (drweb_rc & DERR_BAD_CALL) drweb_s = "wrong command";
956 /* retcodes DERR_SYMLINK, DERR_NO_REGFILE, DERR_SKIPPED.
957 * DERR_TOO_BIG, DERR_TOO_COMPRESSED, DERR_SPAM,
958 * DERR_CRC_ERROR, DERR_READSOCKET, DERR_WRITE_ERR
959 * and others are ignored */
960 if (drweb_s)
961 return m_panic_defer_3(scanent, CUS callout_address,
962 string_sprintf("drweb daemon retcode 0x%x (%s)", drweb_rc, drweb_s),
963 malware_daemon_ctx.sock);
964
965 /* no virus found */
966 malware_name = NULL;
967 }
968 break;
969 } /* drweb */
970 #endif
971
972 #ifndef DISABLE_MAL_AVE
973 case M_AVES: /* "aveserver" scanner type -------------------------------- */
974 {
975 uschar buf[32768];
976 int result;
977
978 /* read aveserver's greeting and see if it is ready (2xx greeting) */
979 buf[0] = 0;
980 recv_line(malware_daemon_ctx.sock, buf, sizeof(buf), tmo);
981
982 if (buf[0] != '2') /* aveserver is having problems */
983 return m_panic_defer_3(scanent, CUS callout_address,
984 string_sprintf("unavailable (Responded: %s).",
985 ((buf[0] != 0) ? buf : US "nothing") ),
986 malware_daemon_ctx.sock);
987
988 /* prepare our command */
989 (void)string_format(buf, sizeof(buf), "SCAN bPQRSTUW %s\r\n",
990 eml_filename);
991
992 /* and send it */
993 DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s %s\n",
994 scanner_name, buf);
995 if (m_sock_send(malware_daemon_ctx.sock, buf, Ustrlen(buf), &errstr) < 0)
996 return m_panic_defer(scanent, CUS callout_address, errstr);
997
998 malware_name = NULL;
999 result = 0;
1000 /* read response lines, find malware name and final response */
1001 while (recv_line(malware_daemon_ctx.sock, buf, sizeof(buf), tmo) > 0)
1002 {
1003 if (buf[0] == '2')
1004 break;
1005 if (buf[0] == '5') /* aveserver is having problems */
1006 {
1007 result = m_panic_defer(scanent, CUS callout_address,
1008 string_sprintf("unable to scan file %s (Responded: %s).",
1009 eml_filename, buf));
1010 break;
1011 }
1012 if (Ustrncmp(buf,"322",3) == 0)
1013 {
1014 uschar *p = Ustrchr(&buf[4], ' ');
1015 *p = '\0';
1016 malware_name = string_copy(&buf[4]);
1017 }
1018 }
1019
1020 if (m_sock_send(malware_daemon_ctx.sock, US"quit\r\n", 6, &errstr) < 0)
1021 return m_panic_defer(scanent, CUS callout_address, errstr);
1022
1023 /* read aveserver's greeting and see if it is ready (2xx greeting) */
1024 buf[0] = 0;
1025 recv_line(malware_daemon_ctx.sock, buf, sizeof(buf), tmo);
1026
1027 if (buf[0] != '2') /* aveserver is having problems */
1028 return m_panic_defer_3(scanent, CUS callout_address,
1029 string_sprintf("unable to quit dialogue (Responded: %s).",
1030 ((buf[0] != 0) ? buf : US "nothing") ),
1031 malware_daemon_ctx.sock);
1032
1033 if (result == DEFER)
1034 {
1035 (void)close(malware_daemon_ctx.sock);
1036 return DEFER;
1037 }
1038 break;
1039 } /* aveserver */
1040 #endif
1041
1042 #ifndef DISABLE_MAL_FSECURE
1043 case M_FSEC: /* "fsecure" scanner type ---------------------------------- */
1044 {
1045 int i, bread = 0;
1046 uschar * file_name;
1047 uschar av_buffer[1024];
1048 static uschar *cmdopt[] = { US"CONFIGURE\tARCHIVE\t1\n",
1049 US"CONFIGURE\tTIMEOUT\t0\n",
1050 US"CONFIGURE\tMAXARCH\t5\n",
1051 US"CONFIGURE\tMIME\t1\n" };
1052
1053 malware_name = NULL;
1054
1055 DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s scan [%s]\n",
1056 scanner_name, scanner_options);
1057 /* pass options */
1058 memset(av_buffer, 0, sizeof(av_buffer));
1059 for (i = 0; i != nelem(cmdopt); i++)
1060 {
1061
1062 if (m_sock_send(malware_daemon_ctx.sock, cmdopt[i], Ustrlen(cmdopt[i]), &errstr) < 0)
1063 return m_panic_defer(scanent, CUS callout_address, errstr);
1064
1065 bread = ip_recv(&malware_daemon_ctx, av_buffer, sizeof(av_buffer), tmo-time(NULL));
1066 if (bread > 0) av_buffer[bread]='\0';
1067 if (bread < 0)
1068 return m_panic_defer_3(scanent, CUS callout_address,
1069 string_sprintf("unable to read answer %d (%s)", i, strerror(errno)),
1070 malware_daemon_ctx.sock);
1071 for (int j = 0; j < bread; j++)
1072 if (av_buffer[j] == '\r' || av_buffer[j] == '\n')
1073 av_buffer[j] ='@';
1074 }
1075
1076 /* pass the mailfile to fsecure */
1077 file_name = string_sprintf("SCAN\t%s\n", eml_filename);
1078
1079 if (m_sock_send(malware_daemon_ctx.sock, file_name, Ustrlen(file_name), &errstr) < 0)
1080 return m_panic_defer(scanent, CUS callout_address, errstr);
1081
1082 /* set up match */
1083 /* todo also SUSPICION\t */
1084 if (!fsec_re)
1085 fsec_re = m_pcre_compile(fsec_re_str, &errstr);
1086
1087 /* read report, linewise. Apply a timeout as the Fsecure daemon
1088 sometimes wants an answer to "PING" but they won't tell us what */
1089 {
1090 uschar * p = av_buffer;
1091 uschar * q;
1092
1093 for (;;)
1094 {
1095 errno = ETIMEDOUT;
1096 i = av_buffer+sizeof(av_buffer)-p;
1097 if ((bread= ip_recv(&malware_daemon_ctx, p, i-1, tmo-time(NULL))) < 0)
1098 return m_panic_defer_3(scanent, CUS callout_address,
1099 string_sprintf("unable to read result (%s)", strerror(errno)),
1100 malware_daemon_ctx.sock);
1101
1102 for (p[bread] = '\0'; (q = Ustrchr(p, '\n')); p = q+1)
1103 {
1104 *q = '\0';
1105
1106 /* Really search for virus again? */
1107 if (!malware_name)
1108 /* try matcher on the line, grab substring */
1109 malware_name = m_pcre_exec(fsec_re, p);
1110
1111 if (Ustrstr(p, "OK\tScan ok."))
1112 goto fsec_found;
1113 }
1114
1115 /* copy down the trailing partial line then read another chunk */
1116 i = av_buffer+sizeof(av_buffer)-p;
1117 memmove(av_buffer, p, i);
1118 p = av_buffer+i;
1119 }
1120 }
1121
1122 fsec_found:
1123 break;
1124 } /* fsecure */
1125 #endif
1126
1127 #ifndef DISABLE_MAL_KAV
1128 case M_KAVD: /* "kavdaemon" scanner type -------------------------------- */
1129 {
1130 time_t t;
1131 uschar tmpbuf[1024];
1132 uschar * scanrequest;
1133 int kav_rc;
1134 unsigned long kav_reportlen;
1135 int bread;
1136 const pcre *kav_re;
1137 uschar *p;
1138
1139 /* get current date and time, build scan request */
1140 time(&t);
1141 /* pdp note: before the eml_filename parameter, this scanned the
1142 directory; not finding documentation, so we'll strip off the directory.
1143 The side-effect is that the test framework scanning may end up in
1144 scanning more than was requested, but for the normal interface, this is
1145 fine. */
1146
1147 strftime(CS tmpbuf, sizeof(tmpbuf), "%d %b %H:%M:%S", localtime(&t));
1148 scanrequest = string_sprintf("<0>%s:%s", CS tmpbuf, eml_filename);
1149 p = Ustrrchr(scanrequest, '/');
1150 if (p)
1151 *p = '\0';
1152
1153 DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s scan [%s]\n",
1154 scanner_name, scanner_options);
1155
1156 /* send scan request */
1157 if (m_sock_send(malware_daemon_ctx.sock, scanrequest, Ustrlen(scanrequest)+1, &errstr) < 0)
1158 return m_panic_defer(scanent, CUS callout_address, errstr);
1159
1160 /* wait for result */
1161 if (!recv_len(malware_daemon_ctx.sock, tmpbuf, 2, tmo))
1162 return m_panic_defer_3(scanent, CUS callout_address,
1163 US"unable to read 2 bytes from socket.", malware_daemon_ctx.sock);
1164
1165 /* get errorcode from one nibble */
1166 kav_rc = tmpbuf[ test_byte_order()==LITTLE_MY_ENDIAN ? 0 : 1 ] & 0x0F;
1167 switch(kav_rc)
1168 {
1169 case 5: case 6: /* improper kavdaemon configuration */
1170 return m_panic_defer_3(scanent, CUS callout_address,
1171 US"please reconfigure kavdaemon to NOT disinfect or remove infected files.",
1172 malware_daemon_ctx.sock);
1173 case 1:
1174 return m_panic_defer_3(scanent, CUS callout_address,
1175 US"reported 'scanning not completed' (code 1).", malware_daemon_ctx.sock);
1176 case 7:
1177 return m_panic_defer_3(scanent, CUS callout_address,
1178 US"reported 'kavdaemon damaged' (code 7).", malware_daemon_ctx.sock);
1179 }
1180
1181 /* code 8 is not handled, since it is ambiguous. It appears mostly on
1182 bounces where part of a file has been cut off */
1183
1184 /* "virus found" return codes (2-4) */
1185 if (kav_rc > 1 && kav_rc < 5)
1186 {
1187 int report_flag = 0;
1188
1189 /* setup default virus name */
1190 malware_name = US"unknown";
1191
1192 report_flag = tmpbuf[ test_byte_order() == LITTLE_MY_ENDIAN ? 1 : 0 ];
1193
1194 /* read the report, if available */
1195 if (report_flag == 1)
1196 {
1197 /* read report size */
1198 if (!recv_len(malware_daemon_ctx.sock, &kav_reportlen, 4, tmo))
1199 return m_panic_defer_3(scanent, CUS callout_address,
1200 US"cannot read report size", malware_daemon_ctx.sock);
1201
1202 /* it's possible that avp returns av_buffer[1] == 1 but the
1203 reportsize is 0 (!?) */
1204 if (kav_reportlen > 0)
1205 {
1206 /* set up match regex, depends on retcode */
1207 if (kav_rc == 3)
1208 {
1209 if (!kav_re_sus) kav_re_sus = m_pcre_compile(kav_re_sus_str, &errstr);
1210 kav_re = kav_re_sus;
1211 }
1212 else
1213 {
1214 if (!kav_re_inf) kav_re_inf = m_pcre_compile(kav_re_inf_str, &errstr);
1215 kav_re = kav_re_inf;
1216 }
1217
1218 /* read report, linewise. Using size from stream to read amount of data
1219 from same stream is safe enough. */
1220 /* coverity[tainted_data] */
1221 while (kav_reportlen > 0)
1222 {
1223 if ((bread = recv_line(malware_daemon_ctx.sock, tmpbuf, sizeof(tmpbuf), tmo)) < 0)
1224 break;
1225 kav_reportlen -= bread+1;
1226
1227 /* try matcher on the line, grab substring */
1228 if ((malware_name = m_pcre_exec(kav_re, tmpbuf)))
1229 break;
1230 }
1231 }
1232 }
1233 }
1234 else /* no virus found */
1235 malware_name = NULL;
1236
1237 break;
1238 }
1239 #endif
1240
1241 #ifndef DISABLE_MAL_CMDLINE
1242 case M_CMDL: /* "cmdline" scanner type ---------------------------------- */
1243 {
1244 const uschar *cmdline_scanner = scanner_options;
1245 const pcre *cmdline_trigger_re;
1246 const pcre *cmdline_regex_re;
1247 uschar * file_name;
1248 uschar * commandline;
1249 void (*eximsigchld)(int);
1250 void (*eximsigpipe)(int);
1251 FILE *scanner_out = NULL;
1252 int scanner_fd;
1253 FILE *scanner_record = NULL;
1254 uschar linebuffer[32767];
1255 int rcnt;
1256 int trigger = 0;
1257 uschar *p;
1258
1259 if (!cmdline_scanner)
1260 return m_panic_defer(scanent, NULL, errstr);
1261
1262 /* find scanner output trigger */
1263 cmdline_trigger_re = m_pcre_nextinlist(&av_scanner_work, &sep,
1264 "missing trigger specification", &errstr);
1265 if (!cmdline_trigger_re)
1266 return m_panic_defer(scanent, NULL, errstr);
1267
1268 /* find scanner name regex */
1269 cmdline_regex_re = m_pcre_nextinlist(&av_scanner_work, &sep,
1270 "missing virus name regex specification", &errstr);
1271 if (!cmdline_regex_re)
1272 return m_panic_defer(scanent, NULL, errstr);
1273
1274 /* prepare scanner call; despite the naming, file_name holds a directory
1275 name which is documented as the value given to %s. */
1276
1277 file_name = string_copy(eml_filename);
1278 p = Ustrrchr(file_name, '/');
1279 if (p)
1280 *p = '\0';
1281 commandline = string_sprintf(CS cmdline_scanner, file_name);
1282
1283 /* redirect STDERR too */
1284 commandline = string_sprintf("%s 2>&1", commandline);
1285
1286 DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s scan [%s]\n",
1287 scanner_name, commandline);
1288
1289 /* store exims signal handlers */
1290 eximsigchld = signal(SIGCHLD,SIG_DFL);
1291 eximsigpipe = signal(SIGPIPE,SIG_DFL);
1292
1293 if (!(scanner_out = popen(CS commandline,"r")))
1294 {
1295 int err = errno;
1296 signal(SIGCHLD,eximsigchld); signal(SIGPIPE,eximsigpipe);
1297 return m_panic_defer(scanent, NULL,
1298 string_sprintf("call (%s) failed: %s.", commandline, strerror(err)));
1299 }
1300 scanner_fd = fileno(scanner_out);
1301
1302 file_name = string_sprintf("%s/%s_scanner_output", eml_dir, message_id);
1303
1304 if (!(scanner_record = modefopen(file_name, "wb", SPOOL_MODE)))
1305 {
1306 int err = errno;
1307 (void) pclose(scanner_out);
1308 signal(SIGCHLD,eximsigchld); signal(SIGPIPE,eximsigpipe);
1309 return m_panic_defer(scanent, NULL, string_sprintf(
1310 "opening scanner output file (%s) failed: %s.",
1311 file_name, strerror(err)));
1312 }
1313
1314 /* look for trigger while recording output */
1315 while ((rcnt = recv_line(scanner_fd, linebuffer,
1316 sizeof(linebuffer), tmo)))
1317 {
1318 if (rcnt < 0)
1319 {
1320 int err = errno;
1321 if (rcnt == -1)
1322 break;
1323 (void) pclose(scanner_out);
1324 signal(SIGCHLD,eximsigchld); signal(SIGPIPE,eximsigpipe);
1325 return m_panic_defer(scanent, NULL, string_sprintf(
1326 "unable to read from scanner (%s): %s",
1327 commandline, strerror(err)));
1328 }
1329
1330 if (Ustrlen(linebuffer) > fwrite(linebuffer, 1, Ustrlen(linebuffer), scanner_record))
1331 {
1332 /* short write */
1333 (void) pclose(scanner_out);
1334 signal(SIGCHLD,eximsigchld); signal(SIGPIPE,eximsigpipe);
1335 return m_panic_defer(scanent, NULL, string_sprintf(
1336 "short write on scanner output file (%s).", file_name));
1337 }
1338 putc('\n', scanner_record);
1339 /* try trigger match */
1340 if ( !trigger
1341 && regex_match_and_setup(cmdline_trigger_re, linebuffer, 0, -1)
1342 )
1343 trigger = 1;
1344 }
1345
1346 (void)fclose(scanner_record);
1347 sep = pclose(scanner_out);
1348 signal(SIGCHLD,eximsigchld); signal(SIGPIPE,eximsigpipe);
1349 if (sep != 0)
1350 return m_panic_defer(scanent, NULL,
1351 sep == -1
1352 ? string_sprintf("running scanner failed: %s", strerror(sep))
1353 : string_sprintf("scanner returned error code: %d", sep));
1354
1355 if (trigger)
1356 {
1357 uschar * s;
1358 /* setup default virus name */
1359 malware_name = US"unknown";
1360
1361 /* re-open the scanner output file, look for name match */
1362 scanner_record = fopen(CS file_name, "rb");
1363 while (fgets(CS linebuffer, sizeof(linebuffer), scanner_record))
1364 {
1365 /* try match */
1366 if ((s = m_pcre_exec(cmdline_regex_re, linebuffer)))
1367 malware_name = s;
1368 }
1369 (void)fclose(scanner_record);
1370 }
1371 else /* no virus found */
1372 malware_name = NULL;
1373 break;
1374 } /* cmdline */
1375 #endif
1376
1377 #ifndef DISABLE_MAL_SOPHIE
1378 case M_SOPHIE: /* "sophie" scanner type --------------------------------- */
1379 {
1380 int bread = 0;
1381 uschar *p;
1382 uschar * file_name;
1383 uschar av_buffer[1024];
1384
1385 /* pass the scan directory to sophie */
1386 file_name = string_copy(eml_filename);
1387 if ((p = Ustrrchr(file_name, '/')))
1388 *p = '\0';
1389
1390 DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s scan [%s]\n",
1391 scanner_name, scanner_options);
1392
1393 if ( write(malware_daemon_ctx.sock, file_name, Ustrlen(file_name)) < 0
1394 || write(malware_daemon_ctx.sock, "\n", 1) != 1
1395 )
1396 return m_panic_defer_3(scanent, CUS callout_address,
1397 string_sprintf("unable to write to UNIX socket (%s)", scanner_options),
1398 malware_daemon_ctx.sock);
1399
1400 /* wait for result */
1401 memset(av_buffer, 0, sizeof(av_buffer));
1402 if ((bread = ip_recv(&malware_daemon_ctx, av_buffer, sizeof(av_buffer), tmo-time(NULL))) <= 0)
1403 return m_panic_defer_3(scanent, CUS callout_address,
1404 string_sprintf("unable to read from UNIX socket (%s)", scanner_options),
1405 malware_daemon_ctx.sock);
1406
1407 /* infected ? */
1408 if (av_buffer[0] == '1') {
1409 uschar * s = Ustrchr(av_buffer, '\n');
1410 if (s)
1411 *s = '\0';
1412 malware_name = string_copy(&av_buffer[2]);
1413 }
1414 else if (!strncmp(CS av_buffer, "-1", 2))
1415 return m_panic_defer_3(scanent, CUS callout_address,
1416 US"scanner reported error", malware_daemon_ctx.sock);
1417 else /* all ok, no virus */
1418 malware_name = NULL;
1419
1420 break;
1421 }
1422 #endif
1423
1424 #ifndef DISABLE_MAL_CLAM
1425 case M_CLAMD: /* "clamd" scanner type ----------------------------------- */
1426 {
1427 /* This code was originally contributed by David Saez */
1428 /* There are three scanning methods available to us:
1429 * (1) Use the SCAN command, pointing to a file in the filesystem
1430 * (2) Use the STREAM command, send the data on a separate port
1431 * (3) Use the zINSTREAM command, send the data inline
1432 * The zINSTREAM command was introduced with ClamAV 0.95, which marked
1433 * STREAM deprecated; see: http://wiki.clamav.net/bin/view/Main/UpgradeNotes095
1434 * In Exim, we use SCAN if using a Unix-domain socket or explicitly told that
1435 * the TCP-connected daemon is actually local; otherwise we use zINSTREAM
1436 * See Exim bug 926 for details. */
1437
1438 uschar *p, *vname, *result_tag;
1439 int bread=0;
1440 uschar av_buffer[1024];
1441 uschar *hostname = US"";
1442 host_item connhost;
1443 uschar *clamav_fbuf;
1444 int clam_fd, result;
1445 off_t fsize;
1446 unsigned int fsize_uint;
1447 BOOL use_scan_command = FALSE;
1448 clamd_address * cv[MAX_CLAMD_SERVERS];
1449 int num_servers = 0;
1450 uint32_t send_size, send_final_zeroblock;
1451 blob cmd_str;
1452
1453 /*XXX if unixdomain socket, only one server supported. Needs fixing;
1454 there's no reason we should not mix local and remote servers */
1455
1456 if (*scanner_options == '/')
1457 {
1458 clamd_address * cd;
1459 const uschar * sublist;
1460 int subsep = ' ';
1461
1462 /* Local file; so we def want to use_scan_command and don't want to try
1463 * passing IP/port combinations */
1464 use_scan_command = TRUE;
1465 cd = (clamd_address *) store_get(sizeof(clamd_address));
1466
1467 /* extract socket-path part */
1468 sublist = scanner_options;
1469 cd->hostspec = string_nextinlist(&sublist, &subsep, NULL, 0);
1470
1471 /* parse options */
1472 if (clamd_option(cd, sublist, &subsep) != OK)
1473 return m_panic_defer(scanent, NULL,
1474 string_sprintf("bad option '%s'", scanner_options));
1475 cv[0] = cd;
1476 }
1477 else
1478 {
1479 /* Go through the rest of the list of host/port and construct an array
1480 * of servers to try. The first one is the bit we just passed from
1481 * scanner_options so process that first and then scan the remainder of
1482 * the address buffer */
1483 do
1484 {
1485 clamd_address * cd;
1486 const uschar * sublist;
1487 int subsep = ' ';
1488 uschar * s;
1489
1490 /* The 'local' option means use the SCAN command over the network
1491 * socket (ie common file storage in use) */
1492 /*XXX we could accept this also as a local option? */
1493 if (strcmpic(scanner_options, US"local") == 0)
1494 {
1495 use_scan_command = TRUE;
1496 continue;
1497 }
1498
1499 cd = (clamd_address *) store_get(sizeof(clamd_address));
1500
1501 /* extract host and port part */
1502 sublist = scanner_options;
1503 if (!(cd->hostspec = string_nextinlist(&sublist, &subsep, NULL, 0)))
1504 {
1505 (void) m_panic_defer(scanent, NULL,
1506 string_sprintf("missing address: '%s'", scanner_options));
1507 continue;
1508 }
1509 if (!(s = string_nextinlist(&sublist, &subsep, NULL, 0)))
1510 {
1511 (void) m_panic_defer(scanent, NULL,
1512 string_sprintf("missing port: '%s'", scanner_options));
1513 continue;
1514 }
1515 cd->tcp_port = atoi(CS s);
1516
1517 /* parse options */
1518 /*XXX should these options be common over scanner types? */
1519 if (clamd_option(cd, sublist, &subsep) != OK)
1520 return m_panic_defer(scanent, NULL,
1521 string_sprintf("bad option '%s'", scanner_options));
1522
1523 cv[num_servers++] = cd;
1524 if (num_servers >= MAX_CLAMD_SERVERS)
1525 {
1526 (void) m_panic_defer(scanent, NULL,
1527 US"More than " MAX_CLAMD_SERVERS_S " clamd servers "
1528 "specified; only using the first " MAX_CLAMD_SERVERS_S );
1529 break;
1530 }
1531 } while ((scanner_options = string_nextinlist(&av_scanner_work, &sep,
1532 NULL, 0)));
1533
1534 /* check if we have at least one server */
1535 if (!num_servers)
1536 return m_panic_defer(scanent, NULL,
1537 US"no useable server addresses in malware configuration option.");
1538 }
1539
1540 /* See the discussion of response formats below to see why we really
1541 don't like colons in filenames when passing filenames to ClamAV. */
1542 if (use_scan_command && Ustrchr(eml_filename, ':'))
1543 return m_panic_defer(scanent, NULL,
1544 string_sprintf("local/SCAN mode incompatible with" \
1545 " : in path to email filename [%s]", eml_filename));
1546
1547 /* Set up the very first data we will be sending */
1548 if (!use_scan_command)
1549 { cmd_str.data = US"zINSTREAM"; cmd_str.len = 10; }
1550 else
1551 {
1552 cmd_str.data = string_sprintf("SCAN %s\n", eml_filename);
1553 cmd_str.len = Ustrlen(cmd_str.data);
1554 }
1555
1556 /* We have some network servers specified */
1557 if (num_servers)
1558 {
1559 /* Confirmed in ClamAV source (0.95.3) that the TCPAddr option of clamd
1560 * only supports AF_INET, but we should probably be looking to the
1561 * future and rewriting this to be protocol-independent anyway. */
1562
1563 while (num_servers > 0)
1564 {
1565 int i = random_number(num_servers);
1566 clamd_address * cd = cv[i];
1567
1568 DEBUG(D_acl) debug_printf_indent("trying server name %s, port %u\n",
1569 cd->hostspec, cd->tcp_port);
1570
1571 /* Lookup the host. This is to ensure that we connect to the same IP
1572 * on both connections (as one host could resolve to multiple ips) */
1573 for (;;)
1574 {
1575 /*XXX we trust that the cmd_str is ideempotent */
1576 if ((malware_daemon_ctx.sock = m_tcpsocket(cd->hostspec, cd->tcp_port,
1577 &connhost, &errstr, &cmd_str)) >= 0)
1578 {
1579 /* Connection successfully established with a server */
1580 hostname = cd->hostspec;
1581 cmd_str.len = 0;
1582 break;
1583 }
1584 if (cd->retry <= 0) break;
1585 while (cd->retry > 0) cd->retry = sleep(cd->retry);
1586 }
1587 if (malware_daemon_ctx.sock >= 0)
1588 break;
1589
1590 (void) m_panic_defer(scanent, CUS callout_address, errstr);
1591
1592 /* Remove the server from the list. XXX We should free the memory */
1593 num_servers--;
1594 for (; i < num_servers; i++)
1595 cv[i] = cv[i+1];
1596 }
1597
1598 if (num_servers == 0)
1599 return m_panic_defer(scanent, NULL, US"all servers failed");
1600 }
1601 else
1602 for (;;)
1603 {
1604 if ((malware_daemon_ctx.sock = ip_unixsocket(cv[0]->hostspec, &errstr)) >= 0)
1605 {
1606 hostname = cv[0]->hostspec;
1607 break;
1608 }
1609 if (cv[0]->retry <= 0)
1610 return m_panic_defer(scanent, CUS callout_address, errstr);
1611 while (cv[0]->retry > 0) cv[0]->retry = sleep(cv[0]->retry);
1612 }
1613
1614 /* have socket in variable "sock"; command to use is semi-independent of
1615 * the socket protocol. We use SCAN if is local (either Unix/local
1616 * domain socket, or explicitly told local) else we stream the data.
1617 * How we stream the data depends upon how we were built. */
1618
1619 if (!use_scan_command)
1620 {
1621 /* New protocol: "zINSTREAM\n" followed by a sequence of <length><data>
1622 chunks, <n> a 4-byte number (network order), terminated by a zero-length
1623 chunk. */
1624
1625 DEBUG(D_acl) debug_printf_indent(
1626 "Malware scan: issuing %s new-style remote scan (zINSTREAM)\n",
1627 scanner_name);
1628
1629 /* Pass the string to ClamAV (10 = "zINSTREAM\0"), if not already sent */
1630 if (cmd_str.len)
1631 if (send(malware_daemon_ctx.sock, cmd_str.data, cmd_str.len, 0) < 0)
1632 return m_panic_defer_3(scanent, CUS hostname,
1633 string_sprintf("unable to send zINSTREAM to socket (%s)",
1634 strerror(errno)),
1635 malware_daemon_ctx.sock);
1636
1637 /* calc file size */
1638 if ((clam_fd = open(CS eml_filename, O_RDONLY)) < 0)
1639 {
1640 int err = errno;
1641 return m_panic_defer_3(scanent, NULL,
1642 string_sprintf("can't open spool file %s: %s",
1643 eml_filename, strerror(err)),
1644 malware_daemon_ctx.sock);
1645 }
1646 if ((fsize = lseek(clam_fd, 0, SEEK_END)) < 0)
1647 {
1648 int err;
1649 b_seek: err = errno;
1650 (void)close(clam_fd);
1651 return m_panic_defer_3(scanent, NULL,
1652 string_sprintf("can't seek spool file %s: %s",
1653 eml_filename, strerror(err)),
1654 malware_daemon_ctx.sock);
1655 }
1656 fsize_uint = (unsigned int) fsize;
1657 if ((off_t)fsize_uint != fsize)
1658 {
1659 (void)close(clam_fd);
1660 return m_panic_defer_3(scanent, NULL,
1661 string_sprintf("seeking spool file %s, size overflow",
1662 eml_filename),
1663 malware_daemon_ctx.sock);
1664 }
1665 if (lseek(clam_fd, 0, SEEK_SET) < 0)
1666 goto b_seek;
1667
1668 if (!(clamav_fbuf = US malloc(fsize_uint)))
1669 {
1670 (void)close(clam_fd);
1671 return m_panic_defer_3(scanent, NULL,
1672 string_sprintf("unable to allocate memory %u for file (%s)",
1673 fsize_uint, eml_filename),
1674 malware_daemon_ctx.sock);
1675 }
1676
1677 if ((result = read(clam_fd, clamav_fbuf, fsize_uint)) < 0)
1678 {
1679 int err = errno;
1680 free(clamav_fbuf); (void)close(clam_fd);
1681 return m_panic_defer_3(scanent, NULL,
1682 string_sprintf("can't read spool file %s: %s",
1683 eml_filename, strerror(err)),
1684 malware_daemon_ctx.sock);
1685 }
1686 (void)close(clam_fd);
1687
1688 /* send file body to socket */
1689 send_size = htonl(fsize_uint);
1690 send_final_zeroblock = 0;
1691 if ((send(malware_daemon_ctx.sock, &send_size, sizeof(send_size), 0) < 0) ||
1692 (send(malware_daemon_ctx.sock, clamav_fbuf, fsize_uint, 0) < 0) ||
1693 (send(malware_daemon_ctx.sock, &send_final_zeroblock, sizeof(send_final_zeroblock), 0) < 0))
1694 {
1695 free(clamav_fbuf);
1696 return m_panic_defer_3(scanent, NULL,
1697 string_sprintf("unable to send file body to socket (%s)", hostname),
1698 malware_daemon_ctx.sock);
1699 }
1700
1701 free(clamav_fbuf);
1702 }
1703 else
1704 { /* use scan command */
1705 /* Send a SCAN command pointing to a filename; then in the then in the
1706 * scan-method-neutral part, read the response back */
1707
1708 /* ================================================================= */
1709
1710 /* Prior to the reworking post-Exim-4.72, this scanned a directory,
1711 which dates to when ClamAV needed us to break apart the email into the
1712 MIME parts (eg, with the now deprecated demime condition coming first).
1713 Some time back, ClamAV gained the ability to deconstruct the emails, so
1714 doing this would actually have resulted in the mail attachments being
1715 scanned twice, in the broken out files and from the original .eml.
1716 Since ClamAV now handles emails (and has for quite some time) we can
1717 just use the email file itself. */
1718 /* Pass the string to ClamAV (7 = "SCAN \n" + \0), if not already sent */
1719
1720 DEBUG(D_acl) debug_printf_indent(
1721 "Malware scan: issuing %s local-path scan [%s]\n",
1722 scanner_name, scanner_options);
1723
1724 if (cmd_str.len)
1725 if (send(malware_daemon_ctx.sock, cmd_str.data, cmd_str.len, 0) < 0)
1726 return m_panic_defer_3(scanent, CUS callout_address,
1727 string_sprintf("unable to write to socket (%s)", strerror(errno)),
1728 malware_daemon_ctx.sock);
1729
1730 /* Do not shut down the socket for writing; a user report noted that
1731 * clamd 0.70 does not react well to this. */
1732 }
1733 /* Commands have been sent, no matter which scan method or connection
1734 * type we're using; now just read the result, independent of method. */
1735
1736 /* Read the result */
1737 memset(av_buffer, 0, sizeof(av_buffer));
1738 bread = ip_recv(&malware_daemon_ctx, av_buffer, sizeof(av_buffer), tmo-time(NULL));
1739 (void)close(malware_daemon_ctx.sock);
1740 malware_daemon_ctx.sock = -1;
1741 malware_daemon_ctx.tls_ctx = NULL;
1742
1743 if (bread <= 0)
1744 return m_panic_defer(scanent, CUS callout_address,
1745 string_sprintf("unable to read from socket (%s)",
1746 errno == 0 ? "EOF" : strerror(errno)));
1747
1748 if (bread == sizeof(av_buffer))
1749 return m_panic_defer(scanent, CUS callout_address,
1750 US"buffer too small");
1751 /* We're now assured of a NULL at the end of av_buffer */
1752
1753 /* Check the result. ClamAV returns one of two result formats.
1754 In the basic mode, the response is of the form:
1755 infected: -> "<filename>: <virusname> FOUND"
1756 not-infected: -> "<filename>: OK"
1757 error: -> "<filename>: <errcode> ERROR
1758 If the ExtendedDetectionInfo option has been turned on, then we get:
1759 "<filename>: <virusname>(<virushash>:<virussize>) FOUND"
1760 for the infected case. Compare:
1761 /tmp/eicar.com: Eicar-Test-Signature FOUND
1762 /tmp/eicar.com: Eicar-Test-Signature(44d88612fea8a8f36de82e1278abb02f:68) FOUND
1763
1764 In the streaming case, clamd uses the filename "stream" which you should
1765 be able to verify with { ktrace clamdscan --stream /tmp/eicar.com }. (The
1766 client app will replace "stream" with the original filename before returning
1767 results to stdout, but the trace shows the data).
1768
1769 We will assume that the pathname passed to clamd from Exim does not contain
1770 a colon. We will have whined loudly above if the eml_filename does (and we're
1771 passing a filename to clamd). */
1772
1773 if (!(*av_buffer))
1774 return m_panic_defer(scanent, CUS callout_address,
1775 US"ClamAV returned null");
1776
1777 /* strip newline at the end (won't be present for zINSTREAM)
1778 (also any trailing whitespace, which shouldn't exist, but we depend upon
1779 this below, so double-check) */
1780 p = av_buffer + Ustrlen(av_buffer) - 1;
1781 if (*p == '\n') *p = '\0';
1782
1783 DEBUG(D_acl) debug_printf_indent("Malware response: %s\n", av_buffer);
1784
1785 while (isspace(*--p) && (p > av_buffer))
1786 *p = '\0';
1787 if (*p) ++p;
1788
1789 /* colon in returned output? */
1790 if(!(p = Ustrchr(av_buffer,':')))
1791 return m_panic_defer(scanent, CUS callout_address, string_sprintf(
1792 "ClamAV returned malformed result (missing colon): %s",
1793 av_buffer));
1794
1795 /* strip filename */
1796 while (*p && isspace(*++p)) /**/;
1797 vname = p;
1798
1799 /* It would be bad to encounter a virus with "FOUND" in part of the name,
1800 but we should at least be resistant to it. */
1801 p = Ustrrchr(vname, ' ');
1802 result_tag = p ? p+1 : vname;
1803
1804 if (Ustrcmp(result_tag, "FOUND") == 0)
1805 {
1806 /* p should still be the whitespace before the result_tag */
1807 while (isspace(*p)) --p;
1808 *++p = '\0';
1809 /* Strip off the extended information too, which will be in parens
1810 after the virus name, with no intervening whitespace. */
1811 if (*--p == ')')
1812 {
1813 /* "(hash:size)", so previous '(' will do; if not found, we have
1814 a curious virus name, but not an error. */
1815 p = Ustrrchr(vname, '(');
1816 if (p)
1817 *p = '\0';
1818 }
1819 malware_name = string_copy(vname);
1820 DEBUG(D_acl) debug_printf_indent("Malware found, name \"%s\"\n", malware_name);
1821
1822 }
1823 else if (Ustrcmp(result_tag, "ERROR") == 0)
1824 return m_panic_defer(scanent, CUS callout_address,
1825 string_sprintf("ClamAV returned: %s", av_buffer));
1826
1827 else if (Ustrcmp(result_tag, "OK") == 0)
1828 {
1829 /* Everything should be OK */
1830 malware_name = NULL;
1831 DEBUG(D_acl) debug_printf_indent("Malware not found\n");
1832
1833 }
1834 else
1835 return m_panic_defer(scanent, CUS callout_address,
1836 string_sprintf("unparseable response from ClamAV: {%s}", av_buffer));
1837
1838 break;
1839 } /* clamd */
1840 #endif
1841
1842 #ifndef DISABLE_MAL_SOCK
1843 case M_SOCK: /* "sock" scanner type ------------------------------------- */
1844 /* This code was derived by Martin Poole from the clamd code contributed
1845 by David Saez and the cmdline code
1846 */
1847 {
1848 int bread;
1849 uschar * commandline;
1850 uschar av_buffer[1024];
1851 uschar * linebuffer;
1852 uschar * sockline_scanner;
1853 uschar sockline_scanner_default[] = "%s\n";
1854 const pcre *sockline_trig_re;
1855 const pcre *sockline_name_re;
1856
1857 /* find scanner command line */
1858 if ( (sockline_scanner = string_nextinlist(&av_scanner_work, &sep,
1859 NULL, 0))
1860 && *sockline_scanner
1861 )
1862 { /* check for no expansions apart from one %s */
1863 uschar * s = Ustrchr(sockline_scanner, '%');
1864 if (s++)
1865 if ((*s != 's' && *s != '%') || Ustrchr(s+1, '%'))
1866 return m_panic_defer_3(scanent, NULL,
1867 US"unsafe sock scanner call spec", malware_daemon_ctx.sock);
1868 }
1869 else
1870 sockline_scanner = sockline_scanner_default;
1871 DEBUG(D_acl) debug_printf_indent("%15s%10s'%s'\n", "", "cmdline: ",
1872 string_printing(sockline_scanner));
1873
1874 /* find scanner output trigger */
1875 sockline_trig_re = m_pcre_nextinlist(&av_scanner_work, &sep,
1876 "missing trigger specification", &errstr);
1877 if (!sockline_trig_re)
1878 return m_panic_defer_3(scanent, NULL, errstr, malware_daemon_ctx.sock);
1879
1880 /* find virus name regex */
1881 sockline_name_re = m_pcre_nextinlist(&av_scanner_work, &sep,
1882 "missing virus name regex specification", &errstr);
1883 if (!sockline_name_re)
1884 return m_panic_defer_3(scanent, NULL, errstr, malware_daemon_ctx.sock);
1885
1886 /* prepare scanner call - security depends on expansions check above */
1887 commandline = string_sprintf( CS sockline_scanner, CS eml_filename);
1888 DEBUG(D_acl) debug_printf_indent("%15s%10s'%s'\n", "", "expanded: ",
1889 string_printing(commandline));
1890
1891 /* Pass the command string to the socket */
1892 if (m_sock_send(malware_daemon_ctx.sock, commandline, Ustrlen(commandline), &errstr) < 0)
1893 return m_panic_defer(scanent, CUS callout_address, errstr);
1894
1895 /* Read the result */
1896 bread = ip_recv(&malware_daemon_ctx, av_buffer, sizeof(av_buffer), tmo-time(NULL));
1897
1898 if (bread <= 0)
1899 return m_panic_defer_3(scanent, CUS callout_address,
1900 string_sprintf("unable to read from socket (%s)", strerror(errno)),
1901 malware_daemon_ctx.sock);
1902
1903 if (bread == sizeof(av_buffer))
1904 return m_panic_defer_3(scanent, CUS callout_address,
1905 US"buffer too small", malware_daemon_ctx.sock);
1906 av_buffer[bread] = '\0';
1907 linebuffer = string_copy(av_buffer);
1908 DEBUG(D_acl) debug_printf_indent("%15s%10s'%s'\n", "", "answer: ",
1909 string_printing(linebuffer));
1910
1911 /* try trigger match */
1912 if (regex_match_and_setup(sockline_trig_re, linebuffer, 0, -1))
1913 {
1914 if (!(malware_name = m_pcre_exec(sockline_name_re, av_buffer)))
1915 malware_name = US "unknown";
1916 DEBUG(D_acl) debug_printf_indent("%15s%10s'%s'\n", "", "name: ",
1917 string_printing(malware_name));
1918 }
1919 else /* no virus found */
1920 malware_name = NULL;
1921 break;
1922 }
1923 #endif
1924
1925 #ifndef DISABLE_MAL_MKS
1926 case M_MKSD: /* "mksd" scanner type ------------------------------------- */
1927 {
1928 char *mksd_options_end;
1929 int mksd_maxproc = 1; /* default, if no option supplied */
1930 int retval;
1931
1932 if (scanner_options)
1933 {
1934 mksd_maxproc = (int)strtol(CS scanner_options, &mksd_options_end, 10);
1935 if ( *scanner_options == '\0'
1936 || *mksd_options_end != '\0'
1937 || mksd_maxproc < 1
1938 || mksd_maxproc > 32
1939 )
1940 return m_panic_defer(scanent, CUS callout_address,
1941 string_sprintf("invalid option '%s'", scanner_options));
1942 }
1943
1944 if((malware_daemon_ctx.sock = ip_unixsocket(US "/var/run/mksd/socket", &errstr)) < 0)
1945 return m_panic_defer(scanent, CUS callout_address, errstr);
1946
1947 malware_name = NULL;
1948
1949 DEBUG(D_acl) debug_printf_indent("Malware scan: issuing %s scan\n", scanner_name);
1950
1951 if ((retval = mksd_scan_packed(scanent, malware_daemon_ctx.sock, eml_filename, tmo)) != OK)
1952 {
1953 close (malware_daemon_ctx.sock);
1954 return retval;
1955 }
1956 break;
1957 }
1958 #endif
1959
1960 #ifndef DISABLE_MAL_AVAST
1961 case M_AVAST: /* "avast" scanner type ----------------------------------- */
1962 {
1963 uschar buf[1024];
1964 uschar * scanrequest;
1965 enum {AVA_HELO, AVA_OPT, AVA_RSP, AVA_DONE} avast_stage;
1966 int nread;
1967 uschar * error_message = NULL;
1968 BOOL more_data = FALSE;
1969 BOOL strict = TRUE;
1970
1971 /* According to Martin Tuma @avast the protocol uses "escaped
1972 whitespace", that is, every embedded whitespace is backslash
1973 escaped, as well as backslash is protected by backslash.
1974 The returned lines contain the name of the scanned file, a tab
1975 and the [ ] marker.
1976 [+] - not infected
1977 [L] - infected
1978 [E] - some error occured
1979 Such marker follows the first non-escaped TAB. For more information
1980 see avast-protocol(5)
1981
1982 We observed two cases:
1983 -> SCAN /file
1984 <- /file [E]0.0 Error 13 Permission denied
1985 <- 451 SCAN Engine error 13 permission denied
1986
1987 -> SCAN /file
1988 <- /file… [E]3.0 Error 41120 The file is a decompression bomb
1989 <- /file… [+]2.0
1990 <- /file… [+]2.0 0 Eicar Test Virus!!!
1991 <- 200 SCAN OK
1992
1993 If the scanner returns 4xx, DEFER is a good decision, combined
1994 with a panic log entry, to get the admin's attention.
1995
1996 If the scanner returns 200, we reject it as malware, if found any,
1997 or, in case of an error, we set the malware message to the error
1998 string.
1999
2000 Some of the >= 42000 errors are message related - usually some
2001 broken archives etc, but some of them are e.g. license related.
2002 Once the license expires the engine starts returning errors for
2003 every scanning attempt. I¹ have the full list of the error codes
2004 but it is not a public API and is subject to change. It is hard
2005 for me to say what you should do in case of an engine error. You
2006 can have a “Treat * unscanned file as infection” policy or “Treat
2007 unscanned file as clean” policy. ¹) Jakub Bednar
2008
2009 */
2010
2011 if ( ( !ava_re_clean
2012 && !(ava_re_clean = m_pcre_compile(ava_re_clean_str, &errstr)))
2013 || ( !ava_re_virus
2014 && !(ava_re_virus = m_pcre_compile(ava_re_virus_str, &errstr)))
2015 || ( !ava_re_error
2016 && !(ava_re_error = m_pcre_compile(ava_re_error_str, &errstr)))
2017 )
2018 return malware_panic_defer(errstr);
2019
2020 /* wait for result */
2021 for (avast_stage = AVA_HELO;
2022 (nread = recv_line(malware_daemon_ctx.sock, buf, sizeof(buf), tmo)) > 0;
2023 )
2024 {
2025 int slen = Ustrlen(buf);
2026 if (slen >= 1)
2027 {
2028
2029 /* Multi line responses are bracketed between 210 … and nnn … */
2030 if (Ustrncmp(buf, "210", 3) == 0)
2031 {
2032 more_data = 1;
2033 continue;
2034 }
2035 else if (more_data && isdigit(buf[0])) more_data = 0;
2036
2037 switch (avast_stage)
2038 {
2039 case AVA_HELO:
2040 if (more_data) continue;
2041 if (Ustrncmp(buf, "220", 3) != 0)
2042 goto endloop; /* require a 220 */
2043 goto sendreq;
2044
2045 case AVA_OPT:
2046 if (more_data) continue;
2047 if (Ustrncmp(buf, "200", 3) != 0)
2048 goto endloop; /* require a 200 */
2049
2050 sendreq:
2051 {
2052 int len;
2053 /* Check for another option to send. Newline-terminate it. */
2054 if ((scanrequest = string_nextinlist(&av_scanner_work, &sep,
2055 NULL, 0)))
2056 {
2057 if (Ustrcmp(scanrequest, "pass_unscanned") == 0)
2058 {
2059 DEBUG(D_acl) debug_printf_indent("pass unscanned files as clean\n");
2060 strict = FALSE;
2061 goto sendreq;
2062 }
2063 scanrequest = string_sprintf("%s\n", scanrequest);
2064 avast_stage = AVA_OPT; /* just sent option */
2065 DEBUG(D_acl) debug_printf_indent("send to avast OPTION: %s", scanrequest);
2066 }
2067 else
2068 {
2069 scanrequest = string_sprintf("SCAN %s\n", eml_dir);
2070 avast_stage = AVA_RSP; /* just sent command */
2071 DEBUG(D_acl) debug_printf_indent("send to avast REQUEST: SCAN %s\n", eml_dir);
2072 }
2073
2074 /* send config-cmd or scan-request to socket */
2075 len = Ustrlen(scanrequest);
2076 if (send(malware_daemon_ctx.sock, scanrequest, len, 0) == -1)
2077 {
2078 scanrequest[len-1] = '\0';
2079 return m_panic_defer_3(scanent, CUS callout_address, string_sprintf(
2080 "unable to send request '%s' to socket (%s): %s",
2081 scanrequest, scanner_options, strerror(errno)), malware_daemon_ctx.sock);
2082 }
2083 break;
2084 }
2085
2086 case AVA_RSP:
2087
2088 if (isdigit(buf[0])) /* We're done */
2089 goto endloop;
2090
2091 if (malware_name) /* Nothing else matters, just read on */
2092 break;
2093
2094 if (pcre_exec(ava_re_clean, NULL, CS buf, slen, 0, 0, NULL, 0) == 0)
2095 break;
2096
2097 if ((malware_name = m_pcre_exec(ava_re_virus, buf)))
2098 {
2099 unescape(malware_name);
2100 DEBUG(D_acl)
2101 debug_printf_indent("unescaped malware name: '%s'\n", malware_name);
2102 break;
2103 }
2104
2105 if (strict) /* treat scanner errors as malware */
2106 {
2107 if ((malware_name = m_pcre_exec(ava_re_error, buf)))
2108 {
2109 unescape(malware_name);
2110 DEBUG(D_acl)
2111 debug_printf_indent("unescaped error message: '%s'\n", malware_name);
2112 break;
2113 }
2114 }
2115 else if (pcre_exec(ava_re_error, NULL, CS buf, slen, 0, 0, NULL, 0) == 0)
2116 {
2117 log_write(0, LOG_MAIN, "internal scanner error (ignored): %s", buf);
2118 break;
2119 }
2120
2121 /* here also for any unexpected response from the scanner */
2122 DEBUG(D_acl) debug_printf("avast response not handled: '%s'\n", buf);
2123
2124 goto endloop;
2125
2126 default: log_write(0, LOG_PANIC, "%s:%d:%s: should not happen",
2127 __FILE__, __LINE__, __FUNCTION__);
2128 }
2129 }
2130 }
2131
2132 endloop:
2133
2134 if (nread == -1) error_message = US"EOF from scanner";
2135 else if (nread < 0) error_message = US"timeout from scanner";
2136 else if (nread == 0) error_message = US"got nothing from scanner";
2137 else if (buf[0] != '2') error_message = buf;
2138
2139 DEBUG(D_acl) debug_printf_indent("sent to avast QUIT\n");
2140 if (send(malware_daemon_ctx.sock, "QUIT\n", 5, 0) == -1)
2141 return m_panic_defer_3(scanent, CUS callout_address,
2142 string_sprintf("unable to send quit request to socket (%s): %s",
2143 scanner_options, strerror(errno)), malware_daemon_ctx.sock);
2144
2145 if (error_message)
2146 return m_panic_defer_3(scanent, CUS callout_address, error_message, malware_daemon_ctx.sock);
2147
2148 }
2149 #endif
2150 } /* scanner type switch */
2151
2152 if (malware_daemon_ctx.sock >= 0)
2153 (void) close (malware_daemon_ctx.sock);
2154 malware_ok = TRUE; /* set "been here, done that" marker */
2155 }
2156
2157 /* match virus name against pattern (caseless ------->----------v) */
2158 if (malware_name && regex_match_and_setup(re, malware_name, 0, -1))
2159 {
2160 DEBUG(D_acl) debug_printf_indent(
2161 "Matched regex to malware [%s] [%s]\n", malware_re, malware_name);
2162 return OK;
2163 }
2164 else
2165 return FAIL;
2166 }
2167
2168
2169 /*************************************************
2170 * Scan an email for malware *
2171 *************************************************/
2172
2173 /* This is the normal interface for scanning an email, which doesn't need a
2174 filename; it's a wrapper around the malware_file function.
2175
2176 Arguments:
2177 malware_re match condition for "malware="
2178 timeout if nonzero, timeout in seconds
2179
2180 Returns: Exim message processing code (OK, FAIL, DEFER, ...)
2181 where true means malware was found (condition applies)
2182 */
2183 int
2184 malware(const uschar * malware_re, int timeout)
2185 {
2186 int ret = malware_internal(malware_re, NULL, timeout);
2187
2188 if (ret == DEFER) av_failed = TRUE;
2189 return ret;
2190 }
2191
2192
2193 /*************************************************
2194 * Scan a file for malware *
2195 *************************************************/
2196
2197 /* This is a test wrapper for scanning an email, which is not used in
2198 normal processing. Scan any file, using the Exim scanning interface.
2199 This function tampers with various global variables so is unsafe to use
2200 in any other context.
2201
2202 Arguments:
2203 eml_filename a file holding the message to be scanned
2204
2205 Returns: Exim message processing code (OK, FAIL, DEFER, ...)
2206 where true means malware was found (condition applies)
2207 */
2208 int
2209 malware_in_file(uschar *eml_filename)
2210 {
2211 uschar message_id_buf[64];
2212 int ret;
2213
2214 /* spool_mbox() assumes various parameters exist, when creating
2215 the relevant directory and the email within */
2216
2217 (void) string_format(message_id_buf, sizeof(message_id_buf),
2218 "dummy-%d", vaguely_random_number(INT_MAX));
2219 message_id = message_id_buf;
2220 sender_address = US"malware-sender@example.net";
2221 return_path = US"";
2222 recipients_list = NULL;
2223 receive_add_recipient(US"malware-victim@example.net", -1);
2224 f.enable_dollar_recipients = TRUE;
2225
2226 ret = malware_internal(US"*", eml_filename, 0);
2227
2228 Ustrncpy(spooled_message_id, message_id, sizeof(spooled_message_id));
2229 spool_mbox_ok = 1;
2230
2231 /* don't set no_mbox_unspool; at present, there's no way for it to become
2232 set, but if that changes, then it should apply to these tests too */
2233
2234 unspool_mbox();
2235
2236 /* silence static analysis tools */
2237 message_id = NULL;
2238
2239 return ret;
2240 }
2241
2242
2243 void
2244 malware_init(void)
2245 {
2246 if (!malware_default_re)
2247 malware_default_re = regex_must_compile(malware_regex_default, FALSE, TRUE);
2248
2249 #ifndef DISABLE_MAL_DRWEB
2250 if (!drweb_re)
2251 drweb_re = regex_must_compile(drweb_re_str, FALSE, TRUE);
2252 #endif
2253 #ifndef DISABLE_MAL_FSECURE
2254 if (!fsec_re)
2255 fsec_re = regex_must_compile(fsec_re_str, FALSE, TRUE);
2256 #endif
2257 #ifndef DISABLE_MAL_KAV
2258 if (!kav_re_sus)
2259 kav_re_sus = regex_must_compile(kav_re_sus_str, FALSE, TRUE);
2260 if (!kav_re_inf)
2261 kav_re_inf = regex_must_compile(kav_re_inf_str, FALSE, TRUE);
2262 #endif
2263 #ifndef DISABLE_MAL_AVAST
2264 if (!ava_re_clean)
2265 ava_re_clean = regex_must_compile(ava_re_clean_str, FALSE, TRUE);
2266 if (!ava_re_virus)
2267 ava_re_virus = regex_must_compile(ava_re_virus_str, FALSE, TRUE);
2268 if (!ava_re_error)
2269 ava_re_error = regex_must_compile(ava_re_error_str, FALSE, TRUE);
2270 #endif
2271 #ifndef DISABLE_MAL_FFROT6D
2272 if (!fprot6d_re_error)
2273 fprot6d_re_error = regex_must_compile(fprot6d_re_error_str, FALSE, TRUE);
2274 if (!fprot6d_re_virus)
2275 fprot6d_re_virus = regex_must_compile(fprot6d_re_virus_str, FALSE, TRUE);
2276 #endif
2277 }
2278
2279
2280 void
2281 malware_show_supported(FILE * f)
2282 {
2283 fprintf(f, "Malware:");
2284 for (struct scan * sc = m_scans; sc->scancode != (scanner_t)-1; sc++) fprintf(f, " %s", sc->name);
2285 fprintf(f, "\n");
2286 }
2287
2288
2289 # endif /*!MACRO_PREDEF*/
2290 #endif /*WITH_CONTENT_SCAN*/
2291 /*
2292 * vi: aw ai sw=2
2293 */