1/*
2 * Copyright (c) 1998-2003, 2006, 2013 Sendmail, Inc. and its suppliers.
3 * All rights reserved.
4 * Copyright (c) 1994, 1996-1997 Eric P. Allman. All rights reserved.
5 * Copyright (c) 1994
6 * The Regents of the University of California. All rights reserved.
7 *
8 * By using this file, you agree to the terms and conditions set
9 * forth in the LICENSE file which can be found at the top level of
10 * the sendmail distribution.
11 *
12 */
13
14#include <sendmail.h>
15#include <string.h>
16
17SM_RCSID("@(#)$Id: mime.c,v 8.148 2013/03/12 15:24:53 ca Exp $")
18
19/*
20** MIME support.
21**
22** I am indebted to John Beck of Hewlett-Packard, who contributed
23** his code to me for inclusion. As it turns out, I did not use
24** his code since he used a "minimum change" approach that used
25** several temp files, and I wanted a "minimum impact" approach
26** that would avoid copying. However, looking over his code
27** helped me cement my understanding of the problem.
28**
29** I also looked at, but did not directly use, Nathaniel
30** Borenstein's "code.c" module. Again, it functioned as
31** a file-to-file translator, which did not fit within my
32** design bounds, but it was a useful base for understanding
33** the problem.
34*/
35
36/* use "old" mime 7 to 8 algorithm by default */
37#ifndef MIME7TO8_OLD
38# define MIME7TO8_OLD 1
39#endif /* ! MIME7TO8_OLD */
40
41#if MIME8TO7
42static int isboundary __P((char *, char **));
43static int mimeboundary __P((char *, char **));
44static int mime_getchar __P((SM_FILE_T *, char **, int *));
45static int mime_getchar_crlf __P((SM_FILE_T *, char **, int *));
46
47/* character set for hex and base64 encoding */
48static char Base16Code[] = "0123456789ABCDEF";
49static char Base64Code[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
50
51/* types of MIME boundaries */
52# define MBT_SYNTAX 0 /* syntax error */
53# define MBT_NOTSEP 1 /* not a boundary */
54# define MBT_INTERMED 2 /* intermediate boundary (no trailing --) */
55# define MBT_FINAL 3 /* final boundary (trailing -- included) */
56
57static char *MimeBoundaryNames[] =
58{
59 "SYNTAX", "NOTSEP", "INTERMED", "FINAL"
60};
61
62static bool MapNLtoCRLF;
63
64/*
65** MIME8TO7 -- output 8 bit body in 7 bit format
66**
67** The header has already been output -- this has to do the
68** 8 to 7 bit conversion. It would be easy if we didn't have
69** to deal with nested formats (multipart/xxx and message/rfc822).
70**
71** We won't be called if we don't have to do a conversion, and
72** appropriate MIME-Version: and Content-Type: fields have been
73** output. Any Content-Transfer-Encoding: field has not been
74** output, and we can add it here.
75**
76** Parameters:
77** mci -- mailer connection information.
78** header -- the header for this body part.
79** e -- envelope.
80** boundaries -- the currently pending message boundaries.
81** NULL if we are processing the outer portion.
82** flags -- to tweak processing.
83** level -- recursion level.
84**
85** Returns:
86** An indicator of what terminated the message part:
87** MBT_FINAL -- the final boundary
88** MBT_INTERMED -- an intermediate boundary
89** MBT_NOTSEP -- an end of file
90** SM_IO_EOF -- I/O error occurred
91*/
92
93struct args
94{
95 char *a_field; /* name of field */
96 char *a_value; /* value of that field */
97};
98
99int
100mime8to7(mci, header, e, boundaries, flags, level)
101 register MCI *mci;
102 HDR *header;
103 register ENVELOPE *e;
104 char **boundaries;
105 int flags;
106 int level;
107{
108 register char *p;
109 int linelen;
110 int blen;
111 int bt;
112 off_t offset;
113 size_t sectionsize, sectionhighbits;
114 int i;
115 char *type;
116 char *subtype;
117 char *cte;
118 char **pvp;
119 int argc = 0;
120 char *bp;
121 bool use_qp = false;
122 struct args argv[MAXMIMEARGS];
123 char bbuf[128];
124 char buf[MAXLINE];
125 char pvpbuf[MAXLINE];
126 extern unsigned char MimeTokenTab[256];
127
128 if (level > MAXMIMENESTING)
129 {
130 if (!bitset(EF_TOODEEP, e->e_flags))
131 {
132 if (tTd(43, 4))
133 sm_dprintf("mime8to7: too deep, level=%d\n",
134 level);
135 usrerr("mime8to7: recursion level %d exceeded",
136 level);
137 e->e_flags |= EF_DONT_MIME|EF_TOODEEP;
138 }
139 }
140 if (tTd(43, 1))
141 {
142 sm_dprintf("mime8to7: flags = %x, boundaries =", flags);
143 if (boundaries[0] == NULL)
144 sm_dprintf(" <none>");
145 else
146 {
147 for (i = 0; boundaries[i] != NULL; i++)
148 sm_dprintf(" %s", boundaries[i]);
149 }
150 sm_dprintf("\n");
151 }
152 MapNLtoCRLF = true;
153 p = hvalue("Content-Transfer-Encoding", header);
154 if (p == NULL ||
155 (pvp = prescan(p, '\0', pvpbuf, sizeof(pvpbuf), NULL,
156 MimeTokenTab, false)) == NULL ||
157 pvp[0] == NULL)
158 {
159 cte = NULL;
160 }
161 else
162 {
163 cataddr(pvp, NULL, buf, sizeof(buf), '\0', false);
164 cte = sm_rpool_strdup_x(e->e_rpool, buf);
165 }
166
167 type = subtype = NULL;
168 p = hvalue("Content-Type", header);
169 if (p == NULL)
170 {
171 if (bitset(M87F_DIGEST, flags))
172 p = "message/rfc822";
173 else
174 p = "text/plain";
175 }
176 if (p != NULL &&
177 (pvp = prescan(p, '\0', pvpbuf, sizeof(pvpbuf), NULL,
178 MimeTokenTab, false)) != NULL &&
179 pvp[0] != NULL)
180 {
181 if (tTd(43, 40))
182 {
183 for (i = 0; pvp[i] != NULL; i++)
184 sm_dprintf("pvp[%d] = \"%s\"\n", i, pvp[i]);
185 }
186 type = *pvp++;
187 if (*pvp != NULL && strcmp(*pvp, "/") == 0 &&
188 *++pvp != NULL)
189 {
190 subtype = *pvp++;
191 }
192
193 /* break out parameters */
194 while (*pvp != NULL && argc < MAXMIMEARGS)
195 {
196 /* skip to semicolon separator */
197 while (*pvp != NULL && strcmp(*pvp, ";") != 0)
198 pvp++;
199 if (*pvp++ == NULL || *pvp == NULL)
200 break;
201
202 /* complain about empty values */
203 if (strcmp(*pvp, ";") == 0)
204 {
205 usrerr("mime8to7: Empty parameter in Content-Type header");
206
207 /* avoid bounce loops */
208 e->e_flags |= EF_DONT_MIME;
209 continue;
210 }
211
212 /* extract field name */
213 argv[argc].a_field = *pvp++;
214
215 /* see if there is a value */
216 if (*pvp != NULL && strcmp(*pvp, "=") == 0 &&
217 (*++pvp == NULL || strcmp(*pvp, ";") != 0))
218 {
219 argv[argc].a_value = *pvp;
220 argc++;
221 }
222 }
223 }
224
225 /* check for disaster cases */
226 if (type == NULL)
227 type = "-none-";
228 if (subtype == NULL)
229 subtype = "-none-";
230
231 /* don't propagate some flags more than one level into the message */
232 flags &= ~M87F_DIGEST;
233
234 /*
235 ** Check for cases that can not be encoded.
236 **
237 ** For example, you can't encode certain kinds of types
238 ** or already-encoded messages. If we find this case,
239 ** just copy it through.
240 */
241
242 (void) sm_snprintf(buf, sizeof(buf), "%.100s/%.100s", type, subtype);
243 if (wordinclass(buf, 'n') || (cte != NULL && !wordinclass(cte, 'e')))
244 flags |= M87F_NO8BIT;
245
246# ifdef USE_B_CLASS
247 if (wordinclass(buf, 'b') || wordinclass(type, 'b'))
248 MapNLtoCRLF = false;
249# endif /* USE_B_CLASS */
250 if (wordinclass(buf, 'q') || wordinclass(type, 'q'))
251 use_qp = true;
252
253 /*
254 ** Multipart requires special processing.
255 **
256 ** Do a recursive descent into the message.
257 */
258
259 if (sm_strcasecmp(type, "multipart") == 0 &&
260 (!bitset(M87F_NO8BIT, flags) || bitset(M87F_NO8TO7, flags)) &&
261 !bitset(EF_TOODEEP, e->e_flags)
262 )
263 {
264
265 if (sm_strcasecmp(subtype, "digest") == 0)
266 flags |= M87F_DIGEST;
267
268 for (i = 0; i < argc; i++)
269 {
270 if (sm_strcasecmp(argv[i].a_field, "boundary") == 0)
271 break;
272 }
273 if (i >= argc || argv[i].a_value == NULL)
274 {
275 usrerr("mime8to7: Content-Type: \"%s\": %s boundary",
276 i >= argc ? "missing" : "bogus", p);
277 p = "---";
278
279 /* avoid bounce loops */
280 e->e_flags |= EF_DONT_MIME;
281 }
282 else
283 {
284 p = argv[i].a_value;
285 stripquotes(p);
286 }
287 if (sm_strlcpy(bbuf, p, sizeof(bbuf)) >= sizeof(bbuf))
288 {
289 usrerr("mime8to7: multipart boundary \"%s\" too long",
290 p);
291
292 /* avoid bounce loops */
293 e->e_flags |= EF_DONT_MIME;
294 }
295
296 if (tTd(43, 1))
297 sm_dprintf("mime8to7: multipart boundary \"%s\"\n",
298 bbuf);
299 for (i = 0; i < MAXMIMENESTING; i++)
300 {
301 if (boundaries[i] == NULL)
302 break;
303 }
304 if (i >= MAXMIMENESTING)
305 {
306 if (tTd(43, 4))
307 sm_dprintf("mime8to7: too deep, i=%d\n", i);
308 if (!bitset(EF_TOODEEP, e->e_flags))
309 usrerr("mime8to7: multipart nesting boundary too deep");
310
311 /* avoid bounce loops */
312 e->e_flags |= EF_DONT_MIME|EF_TOODEEP;
313 }
314 else
315 {
316 boundaries[i] = bbuf;
317 boundaries[i + 1] = NULL;
318 }
319 mci->mci_flags |= MCIF_INMIME;
320
321 /* skip the early "comment" prologue */
322 if (!putline("", mci))
323 goto writeerr;
324 mci->mci_flags &= ~MCIF_INHEADER;
325 bt = MBT_FINAL;
326 while ((blen = sm_io_fgets(e->e_dfp, SM_TIME_DEFAULT, buf,
327 sizeof(buf))) >= 0)
328 {
329 bt = mimeboundary(buf, boundaries);
330 if (bt != MBT_NOTSEP)
331 break;
332 if (!putxline(buf, blen, mci,
333 PXLF_MAPFROM|PXLF_STRIP8BIT))
334 goto writeerr;
335 if (tTd(43, 99))
336 sm_dprintf(" ...%s", buf);
337 }
338 if (sm_io_eof(e->e_dfp))
339 bt = MBT_FINAL;
340 while (bt != MBT_FINAL)
341 {
342 auto HDR *hdr = NULL;
343
344 (void) sm_strlcpyn(buf, sizeof(buf), 2, "--", bbuf);
345 if (!putline(buf, mci))
346 goto writeerr;
347 if (tTd(43, 35))
348 sm_dprintf(" ...%s\n", buf);
349 collect(e->e_dfp, false, &hdr, e, false);
350 if (tTd(43, 101))
351 putline("+++after collect", mci);
352 if (!putheader(mci, hdr, e, flags))
353 goto writeerr;
354 if (tTd(43, 101))
355 putline("+++after putheader", mci);
356 bt = mime8to7(mci, hdr, e, boundaries, flags,
357 level + 1);
358 if (bt == SM_IO_EOF)
359 goto writeerr;
360 }
361 (void) sm_strlcpyn(buf, sizeof(buf), 3, "--", bbuf, "--");
362 if (!putline(buf, mci))
363 goto writeerr;
364 if (tTd(43, 35))
365 sm_dprintf(" ...%s\n", buf);
366 boundaries[i] = NULL;
367 mci->mci_flags &= ~MCIF_INMIME;
368
369 /* skip the late "comment" epilogue */
370 while ((blen = sm_io_fgets(e->e_dfp, SM_TIME_DEFAULT, buf,
371 sizeof(buf))) >= 0)
372 {
373 bt = mimeboundary(buf, boundaries);
374 if (bt != MBT_NOTSEP)
375 break;
376 if (!putxline(buf, blen, mci,
377 PXLF_MAPFROM|PXLF_STRIP8BIT))
378 goto writeerr;
379 if (tTd(43, 99))
380 sm_dprintf(" ...%s", buf);
381 }
382 if (sm_io_eof(e->e_dfp))
383 bt = MBT_FINAL;
384 if (tTd(43, 3))
385 sm_dprintf("\t\t\tmime8to7=>%s (multipart)\n",
386 MimeBoundaryNames[bt]);
387 return bt;
388 }
389
390 /*
391 ** Message/xxx types -- recurse exactly once.
392 **
393 ** Class 's' is predefined to have "rfc822" only.
394 */
395
396 if (sm_strcasecmp(type, "message") == 0)
397 {
398 if (!wordinclass(subtype, 's') ||
399 bitset(EF_TOODEEP, e->e_flags))
400 {
401 flags |= M87F_NO8BIT;
402 }
403 else
404 {
405 auto HDR *hdr = NULL;
406
407 if (!putline("", mci))
408 goto writeerr;
409
410 mci->mci_flags |= MCIF_INMIME;
411 collect(e->e_dfp, false, &hdr, e, false);
412 if (tTd(43, 101))
413 putline("+++after collect", mci);
414 if (!putheader(mci, hdr, e, flags))
415 goto writeerr;
416 if (tTd(43, 101))
417 putline("+++after putheader", mci);
418 if (hvalue("MIME-Version", hdr) == NULL &&
419 !bitset(M87F_NO8TO7, flags) &&
420 !putline("MIME-Version: 1.0", mci))
421 goto writeerr;
422 bt = mime8to7(mci, hdr, e, boundaries, flags,
423 level + 1);
424 mci->mci_flags &= ~MCIF_INMIME;
425 return bt;
426 }
427 }
428
429 /*
430 ** Non-compound body type
431 **
432 ** Compute the ratio of seven to eight bit characters;
433 ** use that as a heuristic to decide how to do the
434 ** encoding.
435 */
436
437 sectionsize = sectionhighbits = 0;
438 if (!bitset(M87F_NO8BIT|M87F_NO8TO7, flags))
439 {
440 /* remember where we were */
441 offset = sm_io_tell(e->e_dfp, SM_TIME_DEFAULT);
442 if (offset == -1)
443 syserr("mime8to7: cannot sm_io_tell on %cf%s",
444 DATAFL_LETTER, e->e_id);
445
446 /* do a scan of this body type to count character types */
447 while ((blen = sm_io_fgets(e->e_dfp, SM_TIME_DEFAULT, buf,
448 sizeof(buf))) >= 0)
449 {
450 if (mimeboundary(buf, boundaries) != MBT_NOTSEP)
451 break;
452 for (i = 0; i < blen; i++)
453 {
454 /* count bytes with the high bit set */
455 sectionsize++;
456 if (bitset(0200, buf[i]))
457 sectionhighbits++;
458 }
459
460 /*
461 ** Heuristic: if 1/4 of the first 4K bytes are 8-bit,
462 ** assume base64. This heuristic avoids double-reading
463 ** large graphics or video files.
464 */
465
466 if (sectionsize >= 4096 &&
467 sectionhighbits > sectionsize / 4)
468 break;
469 }
470
471 /* return to the original offset for processing */
472 /* XXX use relative seeks to handle >31 bit file sizes? */
473 if (sm_io_seek(e->e_dfp, SM_TIME_DEFAULT, offset, SEEK_SET) < 0)
474 syserr("mime8to7: cannot sm_io_fseek on %cf%s",
475 DATAFL_LETTER, e->e_id);
476 else
477 sm_io_clearerr(e->e_dfp);
478 }
479
480 /*
481 ** Heuristically determine encoding method.
482 ** If more than 1/8 of the total characters have the
483 ** eighth bit set, use base64; else use quoted-printable.
484 ** However, only encode binary encoded data as base64,
485 ** since otherwise the NL=>CRLF mapping will be a problem.
486 */
487
488 if (tTd(43, 8))
489 {
490 sm_dprintf("mime8to7: %ld high bit(s) in %ld byte(s), cte=%s, type=%s/%s\n",
491 (long) sectionhighbits, (long) sectionsize,
492 cte == NULL ? "[none]" : cte,
493 type == NULL ? "[none]" : type,
494 subtype == NULL ? "[none]" : subtype);
495 }
496 if (cte != NULL && sm_strcasecmp(cte, "binary") == 0)
497 sectionsize = sectionhighbits;
498 linelen = 0;
499 bp = buf;
500 if (sectionhighbits == 0)
501 {
502 /* no encoding necessary */
503 if (cte != NULL &&
504 bitset(MCIF_CVT8TO7|MCIF_CVT7TO8|MCIF_INMIME,
505 mci->mci_flags) &&
506 !bitset(M87F_NO8TO7, flags))
507 {
508 /*
509 ** Skip _unless_ in MIME mode and potentially
510 ** converting from 8 bit to 7 bit MIME. See
511 ** putheader() for the counterpart where the
512 ** CTE header is skipped in the opposite
513 ** situation.
514 */
515
516 (void) sm_snprintf(buf, sizeof(buf),
517 "Content-Transfer-Encoding: %.200s", cte);
518 if (!putline(buf, mci))
519 goto writeerr;
520 if (tTd(43, 36))
521 sm_dprintf(" ...%s\n", buf);
522 }
523 if (!putline("", mci))
524 goto writeerr;
525 mci->mci_flags &= ~MCIF_INHEADER;
526 while ((blen = sm_io_fgets(e->e_dfp, SM_TIME_DEFAULT, buf,
527 sizeof(buf))) >= 0)
528 {
529 if (!bitset(MCIF_INLONGLINE, mci->mci_flags))
530 {
531 bt = mimeboundary(buf, boundaries);
532 if (bt != MBT_NOTSEP)
533 break;
534 }
535 if (!putxline(buf, blen, mci,
536 PXLF_MAPFROM|PXLF_NOADDEOL))
537 goto writeerr;
538 }
539 if (sm_io_eof(e->e_dfp))
540 bt = MBT_FINAL;
541 }
542 else if (!MapNLtoCRLF ||
543 (sectionsize / 8 < sectionhighbits && !use_qp))
544 {
545 /* use base64 encoding */
546 int c1, c2;
547
548 if (tTd(43, 36))
549 sm_dprintf(" ...Content-Transfer-Encoding: base64\n");
550 if (!putline("Content-Transfer-Encoding: base64", mci))
551 goto writeerr;
552 (void) sm_snprintf(buf, sizeof(buf),
553 "X-MIME-Autoconverted: from 8bit to base64 by %s id %s",
554 MyHostName, e->e_id);
555 if (!putline(buf, mci) || !putline("", mci))
556 goto writeerr;
557 mci->mci_flags &= ~MCIF_INHEADER;
558 while ((c1 = mime_getchar_crlf(e->e_dfp, boundaries, &bt)) !=
559 SM_IO_EOF)
560 {
561 if (linelen > 71)
562 {
563 *bp = '\0';
564 if (!putline(buf, mci))
565 goto writeerr;
566 linelen = 0;
567 bp = buf;
568 }
569 linelen += 4;
570 *bp++ = Base64Code[(c1 >> 2)];
571 c1 = (c1 & 0x03) << 4;
572 c2 = mime_getchar_crlf(e->e_dfp, boundaries, &bt);
573 if (c2 == SM_IO_EOF)
574 {
575 *bp++ = Base64Code[c1];
576 *bp++ = '=';
577 *bp++ = '=';
578 break;
579 }
580 c1 |= (c2 >> 4) & 0x0f;
581 *bp++ = Base64Code[c1];
582 c1 = (c2 & 0x0f) << 2;
583 c2 = mime_getchar_crlf(e->e_dfp, boundaries, &bt);
584 if (c2 == SM_IO_EOF)
585 {
586 *bp++ = Base64Code[c1];
587 *bp++ = '=';
588 break;
589 }
590 c1 |= (c2 >> 6) & 0x03;
591 *bp++ = Base64Code[c1];
592 *bp++ = Base64Code[c2 & 0x3f];
593 }
594 *bp = '\0';
595 if (!putline(buf, mci))
596 goto writeerr;
597 }
598 else
599 {
600 /* use quoted-printable encoding */
601 int c1, c2;
602 int fromstate;
603 BITMAP256 badchars;
604
605 /* set up map of characters that must be mapped */
606 clrbitmap(badchars);
607 for (c1 = 0x00; c1 < 0x20; c1++)
608 setbitn(c1, badchars);
609 clrbitn('\t', badchars);
610 for (c1 = 0x7f; c1 < 0x100; c1++)
611 setbitn(c1, badchars);
612 setbitn('=', badchars);
613 if (bitnset(M_EBCDIC, mci->mci_mailer->m_flags))
614 for (p = "!\"#$@[\\]^`{|}~"; *p != '\0'; p++)
615 setbitn(*p, badchars);
616
617 if (tTd(43, 36))
618 sm_dprintf(" ...Content-Transfer-Encoding: quoted-printable\n");
619 if (!putline("Content-Transfer-Encoding: quoted-printable",
620 mci))
621 goto writeerr;
622 (void) sm_snprintf(buf, sizeof(buf),
623 "X-MIME-Autoconverted: from 8bit to quoted-printable by %s id %s",
624 MyHostName, e->e_id);
625 if (!putline(buf, mci) || !putline("", mci))
626 goto writeerr;
627 mci->mci_flags &= ~MCIF_INHEADER;
628 fromstate = 0;
629 c2 = '\n';
630 while ((c1 = mime_getchar(e->e_dfp, boundaries, &bt)) !=
631 SM_IO_EOF)
632 {
633 if (c1 == '\n')
634 {
635 if (c2 == ' ' || c2 == '\t')
636 {
637 *bp++ = '=';
638 *bp++ = Base16Code[(c2 >> 4) & 0x0f];
639 *bp++ = Base16Code[c2 & 0x0f];
640 }
641 if (buf[0] == '.' && bp == &buf[1])
642 {
643 buf[0] = '=';
644 *bp++ = Base16Code[('.' >> 4) & 0x0f];
645 *bp++ = Base16Code['.' & 0x0f];
646 }
647 *bp = '\0';
648 if (!putline(buf, mci))
649 goto writeerr;
650 linelen = fromstate = 0;
651 bp = buf;
652 c2 = c1;
653 continue;
654 }
655 if (c2 == ' ' && linelen == 4 && fromstate == 4 &&
656 bitnset(M_ESCFROM, mci->mci_mailer->m_flags))
657 {
658 *bp++ = '=';
659 *bp++ = '2';
660 *bp++ = '0';
661 linelen += 3;
662 }
663 else if (c2 == ' ' || c2 == '\t')
664 {
665 *bp++ = c2;
666 linelen++;
667 }
668 if (linelen > 72 &&
669 (linelen > 75 || c1 != '.' ||
670 (linelen > 73 && c2 == '.')))
671 {
672 if (linelen > 73 && c2 == '.')
673 bp--;
674 else
675 c2 = '\n';
676 *bp++ = '=';
677 *bp = '\0';
678 if (!putline(buf, mci))
679 goto writeerr;
680 linelen = fromstate = 0;
681 bp = buf;
682 if (c2 == '.')
683 {
684 *bp++ = '.';
685 linelen++;
686 }
687 }
688 if (bitnset(bitidx(c1), badchars))
689 {
690 *bp++ = '=';
691 *bp++ = Base16Code[(c1 >> 4) & 0x0f];
692 *bp++ = Base16Code[c1 & 0x0f];
693 linelen += 3;
694 }
695 else if (c1 != ' ' && c1 != '\t')
696 {
697 if (linelen < 4 && c1 == "From"[linelen])
698 fromstate++;
699 *bp++ = c1;
700 linelen++;
701 }
702 c2 = c1;
703 }
704
705 /* output any saved character */
706 if (c2 == ' ' || c2 == '\t')
707 {
708 *bp++ = '=';
709 *bp++ = Base16Code[(c2 >> 4) & 0x0f];
710 *bp++ = Base16Code[c2 & 0x0f];
711 linelen += 3;
712 }
713
714 if (linelen > 0 || boundaries[0] != NULL)
715 {
716 *bp = '\0';
717 if (!putline(buf, mci))
718 goto writeerr;
719 }
720
721 }
722 if (tTd(43, 3))
723 sm_dprintf("\t\t\tmime8to7=>%s (basic)\n", MimeBoundaryNames[bt]);
724 return bt;
725
726 writeerr:
727 return SM_IO_EOF;
728}
729/*
730** MIME_GETCHAR -- get a character for MIME processing
731**
732** Treats boundaries as SM_IO_EOF.
733**
734** Parameters:
735** fp -- the input file.
736** boundaries -- the current MIME boundaries.
737** btp -- if the return value is SM_IO_EOF, *btp is set to
738** the type of the boundary.
739**
740** Returns:
741** The next character in the input stream.
742*/
743
744static int
745mime_getchar(fp, boundaries, btp)
746 register SM_FILE_T *fp;
747 char **boundaries;
748 int *btp;
749{
750 int c;
751 static unsigned char *bp = NULL;
752 static int buflen = 0;
753 static bool atbol = true; /* at beginning of line */
754 static int bt = MBT_SYNTAX; /* boundary type of next SM_IO_EOF */
755 static unsigned char buf[128]; /* need not be a full line */
756 int start = 0; /* indicates position of - in buffer */
757
758 if (buflen == 1 && *bp == '\n')
759 {
760 /* last \n in buffer may be part of next MIME boundary */
761 c = *bp;
762 }
763 else if (buflen > 0)
764 {
765 buflen--;
766 return *bp++;
767 }
768 else
769 c = sm_io_getc(fp, SM_TIME_DEFAULT);
770 bp = buf;
771 buflen = 0;
772 if (c == '\n')
773 {
774 /* might be part of a MIME boundary */
775 *bp++ = c;
776 atbol = true;
777 c = sm_io_getc(fp, SM_TIME_DEFAULT);
778 if (c == '\n')
779 {
780 (void) sm_io_ungetc(fp, SM_TIME_DEFAULT, c);
781 return c;
782 }
783 start = 1;
784 }
785 if (c != SM_IO_EOF)
786 *bp++ = c;
787 else
788 bt = MBT_FINAL;
789 if (atbol && c == '-')
790 {
791 /* check for a message boundary */
792 c = sm_io_getc(fp, SM_TIME_DEFAULT);
793 if (c != '-')
794 {
795 if (c != SM_IO_EOF)
796 *bp++ = c;
797 else
798 bt = MBT_FINAL;
799 buflen = bp - buf - 1;
800 bp = buf;
801 return *bp++;
802 }
803
804 /* got "--", now check for rest of separator */
805 *bp++ = '-';
806 while (bp < &buf[sizeof(buf) - 2] &&
807 (c = sm_io_getc(fp, SM_TIME_DEFAULT)) != SM_IO_EOF &&
808 c != '\n')
809 {
810 *bp++ = c;
811 }
812 *bp = '\0'; /* XXX simply cut off? */
813 bt = mimeboundary((char *) &buf[start], boundaries);
814 switch (bt)
815 {
816 case MBT_FINAL:
817 case MBT_INTERMED:
818 /* we have a message boundary */
819 buflen = 0;
820 *btp = bt;
821 return SM_IO_EOF;
822 }
823
824 if (bp < &buf[sizeof(buf) - 2] && c != SM_IO_EOF)
825 *bp++ = c;
826 }
827
828 atbol = c == '\n';
829 buflen = bp - buf - 1;
830 if (buflen < 0)
831 {
832 *btp = bt;
833 return SM_IO_EOF;
834 }
835 bp = buf;
836 return *bp++;
837}
838/*
839** MIME_GETCHAR_CRLF -- do mime_getchar, but translate NL => CRLF
840**
841** Parameters:
842** fp -- the input file.
843** boundaries -- the current MIME boundaries.
844** btp -- if the return value is SM_IO_EOF, *btp is set to
845** the type of the boundary.
846**
847** Returns:
848** The next character in the input stream.
849*/
850
851static int
852mime_getchar_crlf(fp, boundaries, btp)
853 register SM_FILE_T *fp;
854 char **boundaries;
855 int *btp;
856{
857 static bool sendlf = false;
858 int c;
859
860 if (sendlf)
861 {
862 sendlf = false;
863 return '\n';
864 }
865 c = mime_getchar(fp, boundaries, btp);
866 if (c == '\n' && MapNLtoCRLF)
867 {
868 sendlf = true;
869 return '\r';
870 }
871 return c;
872}
873/*
874** MIMEBOUNDARY -- determine if this line is a MIME boundary & its type
875**
876** Parameters:
877** line -- the input line.
878** boundaries -- the set of currently pending boundaries.
879**
880** Returns:
881** MBT_NOTSEP -- if this is not a separator line
882** MBT_INTERMED -- if this is an intermediate separator
883** MBT_FINAL -- if this is a final boundary
884** MBT_SYNTAX -- if this is a boundary for the wrong
885** enclosure -- i.e., a syntax error.
886*/
887
888static int
889mimeboundary(line, boundaries)
890 register char *line;
891 char **boundaries;
892{
893 int type = MBT_NOTSEP;
894 int i;
895 int savec;
896
897 if (line[0] != '-' || line[1] != '-' || boundaries == NULL)
898 return MBT_NOTSEP;
899 i = strlen(line);
900 if (i > 0 && line[i - 1] == '\n')
901 i--;
902
903 /* strip off trailing whitespace */
904 while (i > 0 && (line[i - 1] == ' ' || line[i - 1] == '\t'
905#if _FFR_MIME_CR_OK
906 || line[i - 1] == '\r'
907#endif /* _FFR_MIME_CR_OK */
908 ))
909 i--;
910 savec = line[i];
911 line[i] = '\0';
912
913 if (tTd(43, 5))
914 sm_dprintf("mimeboundary: line=\"%s\"... ", line);
915
916 /* check for this as an intermediate boundary */
917 if (isboundary(&line[2], boundaries) >= 0)
918 type = MBT_INTERMED;
919 else if (i > 2 && strncmp(&line[i - 2], "--", 2) == 0)
920 {
921 /* check for a final boundary */
922 line[i - 2] = '\0';
923 if (isboundary(&line[2], boundaries) >= 0)
924 type = MBT_FINAL;
925 line[i - 2] = '-';
926 }
927
928 line[i] = savec;
929 if (tTd(43, 5))
930 sm_dprintf("%s\n", MimeBoundaryNames[type]);
931 return type;
932}
933/*
934** DEFCHARSET -- return default character set for message
935**
936** The first choice for character set is for the mailer
937** corresponding to the envelope sender. If neither that
938** nor the global configuration file has a default character
939** set defined, return "unknown-8bit" as recommended by
940** RFC 1428 section 3.
941**
942** Parameters:
943** e -- the envelope for this message.
944**
945** Returns:
946** The default character set for that mailer.
947*/
948
949char *
950defcharset(e)
951 register ENVELOPE *e;
952{
953 if (e != NULL && e->e_from.q_mailer != NULL &&
954 e->e_from.q_mailer->m_defcharset != NULL)
955 return e->e_from.q_mailer->m_defcharset;
956 if (DefaultCharSet != NULL)
957 return DefaultCharSet;
958 return "unknown-8bit";
959}
960/*
961** ISBOUNDARY -- is a given string a currently valid boundary?
962**
963** Parameters:
964** line -- the current input line.
965** boundaries -- the list of valid boundaries.
966**
967** Returns:
968** The index number in boundaries if the line is found.
969** -1 -- otherwise.
970**
971*/
972
973static int
974isboundary(line, boundaries)
975 char *line;
976 char **boundaries;
977{
978 register int i;
979
980 for (i = 0; i <= MAXMIMENESTING && boundaries[i] != NULL; i++)
981 {
982 if (strcmp(line, boundaries[i]) == 0)
983 return i;
984 }
985 return -1;
986}
987#endif /* MIME8TO7 */
988
989#if MIME7TO8
990static int mime_fromqp __P((unsigned char *, unsigned char **, int));
991
992/*
993** MIME7TO8 -- output 7 bit encoded MIME body in 8 bit format
994**
995** This is a hack. Supports translating the two 7-bit body-encodings
996** (quoted-printable and base64) to 8-bit coded bodies.
997**
998** There is not much point in supporting multipart here, as the UA
999** will be able to deal with encoded MIME bodies if it can parse MIME
1000** multipart messages.
1001**
1002** Note also that we won't be called unless it is a text/plain MIME
1003** message, encoded base64 or QP and mailer flag '9' has been defined
1004** on mailer.
1005**
1006** Contributed by Marius Olaffson <marius@rhi.hi.is>.
1007**
1008** Parameters:
1009** mci -- mailer connection information.
1010** header -- the header for this body part.
1011** e -- envelope.
1012**
1013** Returns:
1014** true iff body was written successfully
1015*/
1016
1017static char index_64[128] =
1018{
1019 -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
1020 -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
1021 -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,62, -1,-1,-1,63,
1022 52,53,54,55, 56,57,58,59, 60,61,-1,-1, -1,-1,-1,-1,
1023 -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10, 11,12,13,14,
1024 15,16,17,18, 19,20,21,22, 23,24,25,-1, -1,-1,-1,-1,
1025 -1,26,27,28, 29,30,31,32, 33,34,35,36, 37,38,39,40,
1026 41,42,43,44, 45,46,47,48, 49,50,51,-1, -1,-1,-1,-1
1027};
1028
1029# define CHAR64(c) (((c) < 0 || (c) > 127) ? -1 : index_64[(c)])
1030
1031bool
1032mime7to8(mci, header, e)
1033 register MCI *mci;
1034 HDR *header;
1035 register ENVELOPE *e;
1036{
1037 int pxflags, blen;
1038 register char *p;
1039 char *cte;
1040 char **pvp;
1041 unsigned char *fbufp;
1042 char buf[MAXLINE];
1043 unsigned char fbuf[MAXLINE + 1];
1044 char pvpbuf[MAXLINE];
1045 extern unsigned char MimeTokenTab[256];
1046
1047 p = hvalue("Content-Transfer-Encoding", header);
1048 if (p == NULL ||
1049 (pvp = prescan(p, '\0', pvpbuf, sizeof(pvpbuf), NULL,
1050 MimeTokenTab, false)) == NULL ||
1051 pvp[0] == NULL)
1052 {
1053 /* "can't happen" -- upper level should have caught this */
1054 syserr("mime7to8: unparsable CTE %s", p == NULL ? "<NULL>" : p);
1055
1056 /* avoid bounce loops */
1057 e->e_flags |= EF_DONT_MIME;
1058
1059 /* cheap failsafe algorithm -- should work on text/plain */
1060 if (p != NULL)
1061 {
1062 (void) sm_snprintf(buf, sizeof(buf),
1063 "Content-Transfer-Encoding: %s", p);
1064 if (!putline(buf, mci))
1065 goto writeerr;
1066 }
1067 if (!putline("", mci))
1068 goto writeerr;
1069 mci->mci_flags &= ~MCIF_INHEADER;
1070 while ((blen = sm_io_fgets(e->e_dfp, SM_TIME_DEFAULT, buf,
1071 sizeof(buf))) >= 0)
1072 {
1073 if (!putxline(buf, blen, mci, PXLF_MAPFROM))
1074 goto writeerr;
1075 }
1076 return true;
1077 }
1078 cataddr(pvp, NULL, buf, sizeof(buf), '\0', false);
1079 cte = sm_rpool_strdup_x(e->e_rpool, buf);
1080
1081 mci->mci_flags |= MCIF_INHEADER;
1082 if (!putline("Content-Transfer-Encoding: 8bit", mci))
1083 goto writeerr;
1084 (void) sm_snprintf(buf, sizeof(buf),
1085 "X-MIME-Autoconverted: from %.200s to 8bit by %s id %s",
1086 cte, MyHostName, e->e_id);
1087 if (!putline(buf, mci) || !putline("", mci))
1088 goto writeerr;
1089 mci->mci_flags &= ~MCIF_INHEADER;
1090
1091 /*
1092 ** Translate body encoding to 8-bit. Supports two types of
1093 ** encodings; "base64" and "quoted-printable". Assume qp if
1094 ** it is not base64.
1095 */
1096
1097 pxflags = PXLF_MAPFROM;
1098 if (sm_strcasecmp(cte, "base64") == 0)
1099 {
1100 int c1, c2, c3, c4;
1101
1102 fbufp = fbuf;
1103 while ((c1 = sm_io_getc(e->e_dfp, SM_TIME_DEFAULT)) !=
1104 SM_IO_EOF)
1105 {
1106 if (isascii(c1) && isspace(c1))
1107 continue;
1108
1109 do
1110 {
1111 c2 = sm_io_getc(e->e_dfp, SM_TIME_DEFAULT);
1112 } while (isascii(c2) && isspace(c2));
1113 if (c2 == SM_IO_EOF)
1114 break;
1115
1116 do
1117 {
1118 c3 = sm_io_getc(e->e_dfp, SM_TIME_DEFAULT);
1119 } while (isascii(c3) && isspace(c3));
1120 if (c3 == SM_IO_EOF)
1121 break;
1122
1123 do
1124 {
1125 c4 = sm_io_getc(e->e_dfp, SM_TIME_DEFAULT);
1126 } while (isascii(c4) && isspace(c4));
1127 if (c4 == SM_IO_EOF)
1128 break;
1129
1130 if (c1 == '=' || c2 == '=')
1131 continue;
1132 c1 = CHAR64(c1);
1133 c2 = CHAR64(c2);
1134
1135#if MIME7TO8_OLD
1136#define CHK_EOL if (*--fbufp != '\n' || (fbufp > fbuf && *--fbufp != '\r')) \
1137 ++fbufp;
1138#else /* MIME7TO8_OLD */
1139#define CHK_EOL if (*--fbufp != '\n' || (fbufp > fbuf && *--fbufp != '\r')) \
1140 { \
1141 ++fbufp; \
1142 pxflags |= PXLF_NOADDEOL; \
1143 }
1144#endif /* MIME7TO8_OLD */
1145
1146#define PUTLINE64 \
1147 do \
1148 { \
1149 if (*fbufp++ == '\n' || fbufp >= &fbuf[MAXLINE]) \
1150 { \
1151 CHK_EOL; \
1152 if (!putxline((char *) fbuf, fbufp - fbuf, mci, pxflags)) \
1153 goto writeerr; \
1154 pxflags &= ~PXLF_NOADDEOL; \
1155 fbufp = fbuf; \
1156 } \
1157 } while (0)
1158
1159 *fbufp = (c1 << 2) | ((c2 & 0x30) >> 4);
1160 PUTLINE64;
1161 if (c3 == '=')
1162 continue;
1163 c3 = CHAR64(c3);
1164 *fbufp = ((c2 & 0x0f) << 4) | ((c3 & 0x3c) >> 2);
1165 PUTLINE64;
1166 if (c4 == '=')
1167 continue;
1168 c4 = CHAR64(c4);
1169 *fbufp = ((c3 & 0x03) << 6) | c4;
1170 PUTLINE64;
1171 }
1172 }
1173 else
1174 {
1175 int off;
1176
1177 /* quoted-printable */
1178 pxflags |= PXLF_NOADDEOL;
1179 fbufp = fbuf;
1180 while (sm_io_fgets(e->e_dfp, SM_TIME_DEFAULT, buf,
1181 sizeof(buf)) >= 0)
1182 {
1183 off = mime_fromqp((unsigned char *) buf, &fbufp,
1184 &fbuf[MAXLINE] - fbufp);
1185again:
1186 if (off < -1)
1187 continue;
1188
1189 if (fbufp - fbuf > 0)
1190 {
1191 if (!putxline((char *) fbuf, fbufp - fbuf - 1,
1192 mci, pxflags))
1193 goto writeerr;
1194 }
1195 fbufp = fbuf;
1196 if (off >= 0 && buf[off] != '\0')
1197 {
1198 off = mime_fromqp((unsigned char *) (buf + off),
1199 &fbufp,
1200 &fbuf[MAXLINE] - fbufp);
1201 goto again;
1202 }
1203 }
1204 }
1205
1206 /* force out partial last line */
1207 if (fbufp > fbuf)
1208 {
1209 *fbufp = '\0';
1210 if (!putxline((char *) fbuf, fbufp - fbuf, mci, pxflags))
1211 goto writeerr;
1212 }
1213
1214 /*
1215 ** The decoded text may end without an EOL. Since this function
1216 ** is only called for text/plain MIME messages, it is safe to
1217 ** add an extra one at the end just in case. This is a hack,
1218 ** but so is auto-converting MIME in the first place.
1219 */
1220
1221 if (!putline("", mci))
1222 goto writeerr;
1223
1224 if (tTd(43, 3))
1225 sm_dprintf("\t\t\tmime7to8 => %s to 8bit done\n", cte);
1226 return true;
1227
1228 writeerr:
1229 return false;
1230}
1231/*
1232** The following is based on Borenstein's "codes.c" module, with simplifying
1233** changes as we do not deal with multipart, and to do the translation in-core,
1234** with an attempt to prevent overrun of output buffers.
1235**
1236** What is needed here are changes to defend this code better against
1237** bad encodings. Questionable to always return 0xFF for bad mappings.
1238*/
1239
1240static char index_hex[128] =
1241{
1242 -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
1243 -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
1244 -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
1245 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,-1,-1, -1,-1,-1,-1,
1246 -1,10,11,12, 13,14,15,-1, -1,-1,-1,-1, -1,-1,-1,-1,
1247 -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
1248 -1,10,11,12, 13,14,15,-1, -1,-1,-1,-1, -1,-1,-1,-1,
1249 -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1
1250};
1251
1252# define HEXCHAR(c) (((c) < 0 || (c) > 127) ? -1 : index_hex[(c)])
1253
1254/*
1255** MIME_FROMQP -- decode quoted printable string
1256**
1257** Parameters:
1258** infile -- input (encoded) string
1259** outfile -- output string
1260** maxlen -- size of output buffer
1261**
1262** Returns:
1263** -2 if decoding failure
1264** -1 if infile completely decoded into outfile
1265** >= 0 is the position in infile decoding
1266** reached before maxlen was reached
1267*/
1268
1269static int
1270mime_fromqp(infile, outfile, maxlen)
1271 unsigned char *infile;
1272 unsigned char **outfile;
1273 int maxlen; /* Max # of chars allowed in outfile */
1274{
1275 int c1, c2;
1276 int nchar = 0;
1277 unsigned char *b;
1278
1279 /* decrement by one for trailing '\0', at least one other char */
1280 if (--maxlen < 1)
1281 return 0;
1282
1283 b = infile;
1284 while ((c1 = *infile++) != '\0' && nchar < maxlen)
1285 {
1286 if (c1 == '=')
1287 {
1288 if ((c1 = *infile++) == '\0')
1289 break;
1290
1291 if (c1 == '\n' || (c1 = HEXCHAR(c1)) == -1)
1292 {
1293 /* ignore it and the rest of the buffer */
1294 return -2;
1295 }
1296 else
1297 {
1298 do
1299 {
1300 if ((c2 = *infile++) == '\0')
1301 {
1302 c2 = -1;
1303 break;
1304 }
1305 } while ((c2 = HEXCHAR(c2)) == -1);
1306
1307 if (c2 == -1)
1308 break;
1309 nchar++;
1310 *(*outfile)++ = c1 << 4 | c2;
1311 }
1312 }
1313 else
1314 {
1315 nchar++;
1316 *(*outfile)++ = c1;
1317 if (c1 == '\n')
1318 break;
1319 }
1320 }
1321 *(*outfile)++ = '\0';
1322 if (nchar >= maxlen)
1323 return (infile - b - 1);
1324 return -1;
1325}
1326#endif /* MIME7TO8 */
2 * Copyright (c) 1998-2003, 2006, 2013 Sendmail, Inc. and its suppliers.
3 * All rights reserved.
4 * Copyright (c) 1994, 1996-1997 Eric P. Allman. All rights reserved.
5 * Copyright (c) 1994
6 * The Regents of the University of California. All rights reserved.
7 *
8 * By using this file, you agree to the terms and conditions set
9 * forth in the LICENSE file which can be found at the top level of
10 * the sendmail distribution.
11 *
12 */
13
14#include <sendmail.h>
15#include <string.h>
16
17SM_RCSID("@(#)$Id: mime.c,v 8.148 2013/03/12 15:24:53 ca Exp $")
18
19/*
20** MIME support.
21**
22** I am indebted to John Beck of Hewlett-Packard, who contributed
23** his code to me for inclusion. As it turns out, I did not use
24** his code since he used a "minimum change" approach that used
25** several temp files, and I wanted a "minimum impact" approach
26** that would avoid copying. However, looking over his code
27** helped me cement my understanding of the problem.
28**
29** I also looked at, but did not directly use, Nathaniel
30** Borenstein's "code.c" module. Again, it functioned as
31** a file-to-file translator, which did not fit within my
32** design bounds, but it was a useful base for understanding
33** the problem.
34*/
35
36/* use "old" mime 7 to 8 algorithm by default */
37#ifndef MIME7TO8_OLD
38# define MIME7TO8_OLD 1
39#endif /* ! MIME7TO8_OLD */
40
41#if MIME8TO7
42static int isboundary __P((char *, char **));
43static int mimeboundary __P((char *, char **));
44static int mime_getchar __P((SM_FILE_T *, char **, int *));
45static int mime_getchar_crlf __P((SM_FILE_T *, char **, int *));
46
47/* character set for hex and base64 encoding */
48static char Base16Code[] = "0123456789ABCDEF";
49static char Base64Code[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
50
51/* types of MIME boundaries */
52# define MBT_SYNTAX 0 /* syntax error */
53# define MBT_NOTSEP 1 /* not a boundary */
54# define MBT_INTERMED 2 /* intermediate boundary (no trailing --) */
55# define MBT_FINAL 3 /* final boundary (trailing -- included) */
56
57static char *MimeBoundaryNames[] =
58{
59 "SYNTAX", "NOTSEP", "INTERMED", "FINAL"
60};
61
62static bool MapNLtoCRLF;
63
64/*
65** MIME8TO7 -- output 8 bit body in 7 bit format
66**
67** The header has already been output -- this has to do the
68** 8 to 7 bit conversion. It would be easy if we didn't have
69** to deal with nested formats (multipart/xxx and message/rfc822).
70**
71** We won't be called if we don't have to do a conversion, and
72** appropriate MIME-Version: and Content-Type: fields have been
73** output. Any Content-Transfer-Encoding: field has not been
74** output, and we can add it here.
75**
76** Parameters:
77** mci -- mailer connection information.
78** header -- the header for this body part.
79** e -- envelope.
80** boundaries -- the currently pending message boundaries.
81** NULL if we are processing the outer portion.
82** flags -- to tweak processing.
83** level -- recursion level.
84**
85** Returns:
86** An indicator of what terminated the message part:
87** MBT_FINAL -- the final boundary
88** MBT_INTERMED -- an intermediate boundary
89** MBT_NOTSEP -- an end of file
90** SM_IO_EOF -- I/O error occurred
91*/
92
93struct args
94{
95 char *a_field; /* name of field */
96 char *a_value; /* value of that field */
97};
98
99int
100mime8to7(mci, header, e, boundaries, flags, level)
101 register MCI *mci;
102 HDR *header;
103 register ENVELOPE *e;
104 char **boundaries;
105 int flags;
106 int level;
107{
108 register char *p;
109 int linelen;
110 int blen;
111 int bt;
112 off_t offset;
113 size_t sectionsize, sectionhighbits;
114 int i;
115 char *type;
116 char *subtype;
117 char *cte;
118 char **pvp;
119 int argc = 0;
120 char *bp;
121 bool use_qp = false;
122 struct args argv[MAXMIMEARGS];
123 char bbuf[128];
124 char buf[MAXLINE];
125 char pvpbuf[MAXLINE];
126 extern unsigned char MimeTokenTab[256];
127
128 if (level > MAXMIMENESTING)
129 {
130 if (!bitset(EF_TOODEEP, e->e_flags))
131 {
132 if (tTd(43, 4))
133 sm_dprintf("mime8to7: too deep, level=%d\n",
134 level);
135 usrerr("mime8to7: recursion level %d exceeded",
136 level);
137 e->e_flags |= EF_DONT_MIME|EF_TOODEEP;
138 }
139 }
140 if (tTd(43, 1))
141 {
142 sm_dprintf("mime8to7: flags = %x, boundaries =", flags);
143 if (boundaries[0] == NULL)
144 sm_dprintf(" <none>");
145 else
146 {
147 for (i = 0; boundaries[i] != NULL; i++)
148 sm_dprintf(" %s", boundaries[i]);
149 }
150 sm_dprintf("\n");
151 }
152 MapNLtoCRLF = true;
153 p = hvalue("Content-Transfer-Encoding", header);
154 if (p == NULL ||
155 (pvp = prescan(p, '\0', pvpbuf, sizeof(pvpbuf), NULL,
156 MimeTokenTab, false)) == NULL ||
157 pvp[0] == NULL)
158 {
159 cte = NULL;
160 }
161 else
162 {
163 cataddr(pvp, NULL, buf, sizeof(buf), '\0', false);
164 cte = sm_rpool_strdup_x(e->e_rpool, buf);
165 }
166
167 type = subtype = NULL;
168 p = hvalue("Content-Type", header);
169 if (p == NULL)
170 {
171 if (bitset(M87F_DIGEST, flags))
172 p = "message/rfc822";
173 else
174 p = "text/plain";
175 }
176 if (p != NULL &&
177 (pvp = prescan(p, '\0', pvpbuf, sizeof(pvpbuf), NULL,
178 MimeTokenTab, false)) != NULL &&
179 pvp[0] != NULL)
180 {
181 if (tTd(43, 40))
182 {
183 for (i = 0; pvp[i] != NULL; i++)
184 sm_dprintf("pvp[%d] = \"%s\"\n", i, pvp[i]);
185 }
186 type = *pvp++;
187 if (*pvp != NULL && strcmp(*pvp, "/") == 0 &&
188 *++pvp != NULL)
189 {
190 subtype = *pvp++;
191 }
192
193 /* break out parameters */
194 while (*pvp != NULL && argc < MAXMIMEARGS)
195 {
196 /* skip to semicolon separator */
197 while (*pvp != NULL && strcmp(*pvp, ";") != 0)
198 pvp++;
199 if (*pvp++ == NULL || *pvp == NULL)
200 break;
201
202 /* complain about empty values */
203 if (strcmp(*pvp, ";") == 0)
204 {
205 usrerr("mime8to7: Empty parameter in Content-Type header");
206
207 /* avoid bounce loops */
208 e->e_flags |= EF_DONT_MIME;
209 continue;
210 }
211
212 /* extract field name */
213 argv[argc].a_field = *pvp++;
214
215 /* see if there is a value */
216 if (*pvp != NULL && strcmp(*pvp, "=") == 0 &&
217 (*++pvp == NULL || strcmp(*pvp, ";") != 0))
218 {
219 argv[argc].a_value = *pvp;
220 argc++;
221 }
222 }
223 }
224
225 /* check for disaster cases */
226 if (type == NULL)
227 type = "-none-";
228 if (subtype == NULL)
229 subtype = "-none-";
230
231 /* don't propagate some flags more than one level into the message */
232 flags &= ~M87F_DIGEST;
233
234 /*
235 ** Check for cases that can not be encoded.
236 **
237 ** For example, you can't encode certain kinds of types
238 ** or already-encoded messages. If we find this case,
239 ** just copy it through.
240 */
241
242 (void) sm_snprintf(buf, sizeof(buf), "%.100s/%.100s", type, subtype);
243 if (wordinclass(buf, 'n') || (cte != NULL && !wordinclass(cte, 'e')))
244 flags |= M87F_NO8BIT;
245
246# ifdef USE_B_CLASS
247 if (wordinclass(buf, 'b') || wordinclass(type, 'b'))
248 MapNLtoCRLF = false;
249# endif /* USE_B_CLASS */
250 if (wordinclass(buf, 'q') || wordinclass(type, 'q'))
251 use_qp = true;
252
253 /*
254 ** Multipart requires special processing.
255 **
256 ** Do a recursive descent into the message.
257 */
258
259 if (sm_strcasecmp(type, "multipart") == 0 &&
260 (!bitset(M87F_NO8BIT, flags) || bitset(M87F_NO8TO7, flags)) &&
261 !bitset(EF_TOODEEP, e->e_flags)
262 )
263 {
264
265 if (sm_strcasecmp(subtype, "digest") == 0)
266 flags |= M87F_DIGEST;
267
268 for (i = 0; i < argc; i++)
269 {
270 if (sm_strcasecmp(argv[i].a_field, "boundary") == 0)
271 break;
272 }
273 if (i >= argc || argv[i].a_value == NULL)
274 {
275 usrerr("mime8to7: Content-Type: \"%s\": %s boundary",
276 i >= argc ? "missing" : "bogus", p);
277 p = "---";
278
279 /* avoid bounce loops */
280 e->e_flags |= EF_DONT_MIME;
281 }
282 else
283 {
284 p = argv[i].a_value;
285 stripquotes(p);
286 }
287 if (sm_strlcpy(bbuf, p, sizeof(bbuf)) >= sizeof(bbuf))
288 {
289 usrerr("mime8to7: multipart boundary \"%s\" too long",
290 p);
291
292 /* avoid bounce loops */
293 e->e_flags |= EF_DONT_MIME;
294 }
295
296 if (tTd(43, 1))
297 sm_dprintf("mime8to7: multipart boundary \"%s\"\n",
298 bbuf);
299 for (i = 0; i < MAXMIMENESTING; i++)
300 {
301 if (boundaries[i] == NULL)
302 break;
303 }
304 if (i >= MAXMIMENESTING)
305 {
306 if (tTd(43, 4))
307 sm_dprintf("mime8to7: too deep, i=%d\n", i);
308 if (!bitset(EF_TOODEEP, e->e_flags))
309 usrerr("mime8to7: multipart nesting boundary too deep");
310
311 /* avoid bounce loops */
312 e->e_flags |= EF_DONT_MIME|EF_TOODEEP;
313 }
314 else
315 {
316 boundaries[i] = bbuf;
317 boundaries[i + 1] = NULL;
318 }
319 mci->mci_flags |= MCIF_INMIME;
320
321 /* skip the early "comment" prologue */
322 if (!putline("", mci))
323 goto writeerr;
324 mci->mci_flags &= ~MCIF_INHEADER;
325 bt = MBT_FINAL;
326 while ((blen = sm_io_fgets(e->e_dfp, SM_TIME_DEFAULT, buf,
327 sizeof(buf))) >= 0)
328 {
329 bt = mimeboundary(buf, boundaries);
330 if (bt != MBT_NOTSEP)
331 break;
332 if (!putxline(buf, blen, mci,
333 PXLF_MAPFROM|PXLF_STRIP8BIT))
334 goto writeerr;
335 if (tTd(43, 99))
336 sm_dprintf(" ...%s", buf);
337 }
338 if (sm_io_eof(e->e_dfp))
339 bt = MBT_FINAL;
340 while (bt != MBT_FINAL)
341 {
342 auto HDR *hdr = NULL;
343
344 (void) sm_strlcpyn(buf, sizeof(buf), 2, "--", bbuf);
345 if (!putline(buf, mci))
346 goto writeerr;
347 if (tTd(43, 35))
348 sm_dprintf(" ...%s\n", buf);
349 collect(e->e_dfp, false, &hdr, e, false);
350 if (tTd(43, 101))
351 putline("+++after collect", mci);
352 if (!putheader(mci, hdr, e, flags))
353 goto writeerr;
354 if (tTd(43, 101))
355 putline("+++after putheader", mci);
356 bt = mime8to7(mci, hdr, e, boundaries, flags,
357 level + 1);
358 if (bt == SM_IO_EOF)
359 goto writeerr;
360 }
361 (void) sm_strlcpyn(buf, sizeof(buf), 3, "--", bbuf, "--");
362 if (!putline(buf, mci))
363 goto writeerr;
364 if (tTd(43, 35))
365 sm_dprintf(" ...%s\n", buf);
366 boundaries[i] = NULL;
367 mci->mci_flags &= ~MCIF_INMIME;
368
369 /* skip the late "comment" epilogue */
370 while ((blen = sm_io_fgets(e->e_dfp, SM_TIME_DEFAULT, buf,
371 sizeof(buf))) >= 0)
372 {
373 bt = mimeboundary(buf, boundaries);
374 if (bt != MBT_NOTSEP)
375 break;
376 if (!putxline(buf, blen, mci,
377 PXLF_MAPFROM|PXLF_STRIP8BIT))
378 goto writeerr;
379 if (tTd(43, 99))
380 sm_dprintf(" ...%s", buf);
381 }
382 if (sm_io_eof(e->e_dfp))
383 bt = MBT_FINAL;
384 if (tTd(43, 3))
385 sm_dprintf("\t\t\tmime8to7=>%s (multipart)\n",
386 MimeBoundaryNames[bt]);
387 return bt;
388 }
389
390 /*
391 ** Message/xxx types -- recurse exactly once.
392 **
393 ** Class 's' is predefined to have "rfc822" only.
394 */
395
396 if (sm_strcasecmp(type, "message") == 0)
397 {
398 if (!wordinclass(subtype, 's') ||
399 bitset(EF_TOODEEP, e->e_flags))
400 {
401 flags |= M87F_NO8BIT;
402 }
403 else
404 {
405 auto HDR *hdr = NULL;
406
407 if (!putline("", mci))
408 goto writeerr;
409
410 mci->mci_flags |= MCIF_INMIME;
411 collect(e->e_dfp, false, &hdr, e, false);
412 if (tTd(43, 101))
413 putline("+++after collect", mci);
414 if (!putheader(mci, hdr, e, flags))
415 goto writeerr;
416 if (tTd(43, 101))
417 putline("+++after putheader", mci);
418 if (hvalue("MIME-Version", hdr) == NULL &&
419 !bitset(M87F_NO8TO7, flags) &&
420 !putline("MIME-Version: 1.0", mci))
421 goto writeerr;
422 bt = mime8to7(mci, hdr, e, boundaries, flags,
423 level + 1);
424 mci->mci_flags &= ~MCIF_INMIME;
425 return bt;
426 }
427 }
428
429 /*
430 ** Non-compound body type
431 **
432 ** Compute the ratio of seven to eight bit characters;
433 ** use that as a heuristic to decide how to do the
434 ** encoding.
435 */
436
437 sectionsize = sectionhighbits = 0;
438 if (!bitset(M87F_NO8BIT|M87F_NO8TO7, flags))
439 {
440 /* remember where we were */
441 offset = sm_io_tell(e->e_dfp, SM_TIME_DEFAULT);
442 if (offset == -1)
443 syserr("mime8to7: cannot sm_io_tell on %cf%s",
444 DATAFL_LETTER, e->e_id);
445
446 /* do a scan of this body type to count character types */
447 while ((blen = sm_io_fgets(e->e_dfp, SM_TIME_DEFAULT, buf,
448 sizeof(buf))) >= 0)
449 {
450 if (mimeboundary(buf, boundaries) != MBT_NOTSEP)
451 break;
452 for (i = 0; i < blen; i++)
453 {
454 /* count bytes with the high bit set */
455 sectionsize++;
456 if (bitset(0200, buf[i]))
457 sectionhighbits++;
458 }
459
460 /*
461 ** Heuristic: if 1/4 of the first 4K bytes are 8-bit,
462 ** assume base64. This heuristic avoids double-reading
463 ** large graphics or video files.
464 */
465
466 if (sectionsize >= 4096 &&
467 sectionhighbits > sectionsize / 4)
468 break;
469 }
470
471 /* return to the original offset for processing */
472 /* XXX use relative seeks to handle >31 bit file sizes? */
473 if (sm_io_seek(e->e_dfp, SM_TIME_DEFAULT, offset, SEEK_SET) < 0)
474 syserr("mime8to7: cannot sm_io_fseek on %cf%s",
475 DATAFL_LETTER, e->e_id);
476 else
477 sm_io_clearerr(e->e_dfp);
478 }
479
480 /*
481 ** Heuristically determine encoding method.
482 ** If more than 1/8 of the total characters have the
483 ** eighth bit set, use base64; else use quoted-printable.
484 ** However, only encode binary encoded data as base64,
485 ** since otherwise the NL=>CRLF mapping will be a problem.
486 */
487
488 if (tTd(43, 8))
489 {
490 sm_dprintf("mime8to7: %ld high bit(s) in %ld byte(s), cte=%s, type=%s/%s\n",
491 (long) sectionhighbits, (long) sectionsize,
492 cte == NULL ? "[none]" : cte,
493 type == NULL ? "[none]" : type,
494 subtype == NULL ? "[none]" : subtype);
495 }
496 if (cte != NULL && sm_strcasecmp(cte, "binary") == 0)
497 sectionsize = sectionhighbits;
498 linelen = 0;
499 bp = buf;
500 if (sectionhighbits == 0)
501 {
502 /* no encoding necessary */
503 if (cte != NULL &&
504 bitset(MCIF_CVT8TO7|MCIF_CVT7TO8|MCIF_INMIME,
505 mci->mci_flags) &&
506 !bitset(M87F_NO8TO7, flags))
507 {
508 /*
509 ** Skip _unless_ in MIME mode and potentially
510 ** converting from 8 bit to 7 bit MIME. See
511 ** putheader() for the counterpart where the
512 ** CTE header is skipped in the opposite
513 ** situation.
514 */
515
516 (void) sm_snprintf(buf, sizeof(buf),
517 "Content-Transfer-Encoding: %.200s", cte);
518 if (!putline(buf, mci))
519 goto writeerr;
520 if (tTd(43, 36))
521 sm_dprintf(" ...%s\n", buf);
522 }
523 if (!putline("", mci))
524 goto writeerr;
525 mci->mci_flags &= ~MCIF_INHEADER;
526 while ((blen = sm_io_fgets(e->e_dfp, SM_TIME_DEFAULT, buf,
527 sizeof(buf))) >= 0)
528 {
529 if (!bitset(MCIF_INLONGLINE, mci->mci_flags))
530 {
531 bt = mimeboundary(buf, boundaries);
532 if (bt != MBT_NOTSEP)
533 break;
534 }
535 if (!putxline(buf, blen, mci,
536 PXLF_MAPFROM|PXLF_NOADDEOL))
537 goto writeerr;
538 }
539 if (sm_io_eof(e->e_dfp))
540 bt = MBT_FINAL;
541 }
542 else if (!MapNLtoCRLF ||
543 (sectionsize / 8 < sectionhighbits && !use_qp))
544 {
545 /* use base64 encoding */
546 int c1, c2;
547
548 if (tTd(43, 36))
549 sm_dprintf(" ...Content-Transfer-Encoding: base64\n");
550 if (!putline("Content-Transfer-Encoding: base64", mci))
551 goto writeerr;
552 (void) sm_snprintf(buf, sizeof(buf),
553 "X-MIME-Autoconverted: from 8bit to base64 by %s id %s",
554 MyHostName, e->e_id);
555 if (!putline(buf, mci) || !putline("", mci))
556 goto writeerr;
557 mci->mci_flags &= ~MCIF_INHEADER;
558 while ((c1 = mime_getchar_crlf(e->e_dfp, boundaries, &bt)) !=
559 SM_IO_EOF)
560 {
561 if (linelen > 71)
562 {
563 *bp = '\0';
564 if (!putline(buf, mci))
565 goto writeerr;
566 linelen = 0;
567 bp = buf;
568 }
569 linelen += 4;
570 *bp++ = Base64Code[(c1 >> 2)];
571 c1 = (c1 & 0x03) << 4;
572 c2 = mime_getchar_crlf(e->e_dfp, boundaries, &bt);
573 if (c2 == SM_IO_EOF)
574 {
575 *bp++ = Base64Code[c1];
576 *bp++ = '=';
577 *bp++ = '=';
578 break;
579 }
580 c1 |= (c2 >> 4) & 0x0f;
581 *bp++ = Base64Code[c1];
582 c1 = (c2 & 0x0f) << 2;
583 c2 = mime_getchar_crlf(e->e_dfp, boundaries, &bt);
584 if (c2 == SM_IO_EOF)
585 {
586 *bp++ = Base64Code[c1];
587 *bp++ = '=';
588 break;
589 }
590 c1 |= (c2 >> 6) & 0x03;
591 *bp++ = Base64Code[c1];
592 *bp++ = Base64Code[c2 & 0x3f];
593 }
594 *bp = '\0';
595 if (!putline(buf, mci))
596 goto writeerr;
597 }
598 else
599 {
600 /* use quoted-printable encoding */
601 int c1, c2;
602 int fromstate;
603 BITMAP256 badchars;
604
605 /* set up map of characters that must be mapped */
606 clrbitmap(badchars);
607 for (c1 = 0x00; c1 < 0x20; c1++)
608 setbitn(c1, badchars);
609 clrbitn('\t', badchars);
610 for (c1 = 0x7f; c1 < 0x100; c1++)
611 setbitn(c1, badchars);
612 setbitn('=', badchars);
613 if (bitnset(M_EBCDIC, mci->mci_mailer->m_flags))
614 for (p = "!\"#$@[\\]^`{|}~"; *p != '\0'; p++)
615 setbitn(*p, badchars);
616
617 if (tTd(43, 36))
618 sm_dprintf(" ...Content-Transfer-Encoding: quoted-printable\n");
619 if (!putline("Content-Transfer-Encoding: quoted-printable",
620 mci))
621 goto writeerr;
622 (void) sm_snprintf(buf, sizeof(buf),
623 "X-MIME-Autoconverted: from 8bit to quoted-printable by %s id %s",
624 MyHostName, e->e_id);
625 if (!putline(buf, mci) || !putline("", mci))
626 goto writeerr;
627 mci->mci_flags &= ~MCIF_INHEADER;
628 fromstate = 0;
629 c2 = '\n';
630 while ((c1 = mime_getchar(e->e_dfp, boundaries, &bt)) !=
631 SM_IO_EOF)
632 {
633 if (c1 == '\n')
634 {
635 if (c2 == ' ' || c2 == '\t')
636 {
637 *bp++ = '=';
638 *bp++ = Base16Code[(c2 >> 4) & 0x0f];
639 *bp++ = Base16Code[c2 & 0x0f];
640 }
641 if (buf[0] == '.' && bp == &buf[1])
642 {
643 buf[0] = '=';
644 *bp++ = Base16Code[('.' >> 4) & 0x0f];
645 *bp++ = Base16Code['.' & 0x0f];
646 }
647 *bp = '\0';
648 if (!putline(buf, mci))
649 goto writeerr;
650 linelen = fromstate = 0;
651 bp = buf;
652 c2 = c1;
653 continue;
654 }
655 if (c2 == ' ' && linelen == 4 && fromstate == 4 &&
656 bitnset(M_ESCFROM, mci->mci_mailer->m_flags))
657 {
658 *bp++ = '=';
659 *bp++ = '2';
660 *bp++ = '0';
661 linelen += 3;
662 }
663 else if (c2 == ' ' || c2 == '\t')
664 {
665 *bp++ = c2;
666 linelen++;
667 }
668 if (linelen > 72 &&
669 (linelen > 75 || c1 != '.' ||
670 (linelen > 73 && c2 == '.')))
671 {
672 if (linelen > 73 && c2 == '.')
673 bp--;
674 else
675 c2 = '\n';
676 *bp++ = '=';
677 *bp = '\0';
678 if (!putline(buf, mci))
679 goto writeerr;
680 linelen = fromstate = 0;
681 bp = buf;
682 if (c2 == '.')
683 {
684 *bp++ = '.';
685 linelen++;
686 }
687 }
688 if (bitnset(bitidx(c1), badchars))
689 {
690 *bp++ = '=';
691 *bp++ = Base16Code[(c1 >> 4) & 0x0f];
692 *bp++ = Base16Code[c1 & 0x0f];
693 linelen += 3;
694 }
695 else if (c1 != ' ' && c1 != '\t')
696 {
697 if (linelen < 4 && c1 == "From"[linelen])
698 fromstate++;
699 *bp++ = c1;
700 linelen++;
701 }
702 c2 = c1;
703 }
704
705 /* output any saved character */
706 if (c2 == ' ' || c2 == '\t')
707 {
708 *bp++ = '=';
709 *bp++ = Base16Code[(c2 >> 4) & 0x0f];
710 *bp++ = Base16Code[c2 & 0x0f];
711 linelen += 3;
712 }
713
714 if (linelen > 0 || boundaries[0] != NULL)
715 {
716 *bp = '\0';
717 if (!putline(buf, mci))
718 goto writeerr;
719 }
720
721 }
722 if (tTd(43, 3))
723 sm_dprintf("\t\t\tmime8to7=>%s (basic)\n", MimeBoundaryNames[bt]);
724 return bt;
725
726 writeerr:
727 return SM_IO_EOF;
728}
729/*
730** MIME_GETCHAR -- get a character for MIME processing
731**
732** Treats boundaries as SM_IO_EOF.
733**
734** Parameters:
735** fp -- the input file.
736** boundaries -- the current MIME boundaries.
737** btp -- if the return value is SM_IO_EOF, *btp is set to
738** the type of the boundary.
739**
740** Returns:
741** The next character in the input stream.
742*/
743
744static int
745mime_getchar(fp, boundaries, btp)
746 register SM_FILE_T *fp;
747 char **boundaries;
748 int *btp;
749{
750 int c;
751 static unsigned char *bp = NULL;
752 static int buflen = 0;
753 static bool atbol = true; /* at beginning of line */
754 static int bt = MBT_SYNTAX; /* boundary type of next SM_IO_EOF */
755 static unsigned char buf[128]; /* need not be a full line */
756 int start = 0; /* indicates position of - in buffer */
757
758 if (buflen == 1 && *bp == '\n')
759 {
760 /* last \n in buffer may be part of next MIME boundary */
761 c = *bp;
762 }
763 else if (buflen > 0)
764 {
765 buflen--;
766 return *bp++;
767 }
768 else
769 c = sm_io_getc(fp, SM_TIME_DEFAULT);
770 bp = buf;
771 buflen = 0;
772 if (c == '\n')
773 {
774 /* might be part of a MIME boundary */
775 *bp++ = c;
776 atbol = true;
777 c = sm_io_getc(fp, SM_TIME_DEFAULT);
778 if (c == '\n')
779 {
780 (void) sm_io_ungetc(fp, SM_TIME_DEFAULT, c);
781 return c;
782 }
783 start = 1;
784 }
785 if (c != SM_IO_EOF)
786 *bp++ = c;
787 else
788 bt = MBT_FINAL;
789 if (atbol && c == '-')
790 {
791 /* check for a message boundary */
792 c = sm_io_getc(fp, SM_TIME_DEFAULT);
793 if (c != '-')
794 {
795 if (c != SM_IO_EOF)
796 *bp++ = c;
797 else
798 bt = MBT_FINAL;
799 buflen = bp - buf - 1;
800 bp = buf;
801 return *bp++;
802 }
803
804 /* got "--", now check for rest of separator */
805 *bp++ = '-';
806 while (bp < &buf[sizeof(buf) - 2] &&
807 (c = sm_io_getc(fp, SM_TIME_DEFAULT)) != SM_IO_EOF &&
808 c != '\n')
809 {
810 *bp++ = c;
811 }
812 *bp = '\0'; /* XXX simply cut off? */
813 bt = mimeboundary((char *) &buf[start], boundaries);
814 switch (bt)
815 {
816 case MBT_FINAL:
817 case MBT_INTERMED:
818 /* we have a message boundary */
819 buflen = 0;
820 *btp = bt;
821 return SM_IO_EOF;
822 }
823
824 if (bp < &buf[sizeof(buf) - 2] && c != SM_IO_EOF)
825 *bp++ = c;
826 }
827
828 atbol = c == '\n';
829 buflen = bp - buf - 1;
830 if (buflen < 0)
831 {
832 *btp = bt;
833 return SM_IO_EOF;
834 }
835 bp = buf;
836 return *bp++;
837}
838/*
839** MIME_GETCHAR_CRLF -- do mime_getchar, but translate NL => CRLF
840**
841** Parameters:
842** fp -- the input file.
843** boundaries -- the current MIME boundaries.
844** btp -- if the return value is SM_IO_EOF, *btp is set to
845** the type of the boundary.
846**
847** Returns:
848** The next character in the input stream.
849*/
850
851static int
852mime_getchar_crlf(fp, boundaries, btp)
853 register SM_FILE_T *fp;
854 char **boundaries;
855 int *btp;
856{
857 static bool sendlf = false;
858 int c;
859
860 if (sendlf)
861 {
862 sendlf = false;
863 return '\n';
864 }
865 c = mime_getchar(fp, boundaries, btp);
866 if (c == '\n' && MapNLtoCRLF)
867 {
868 sendlf = true;
869 return '\r';
870 }
871 return c;
872}
873/*
874** MIMEBOUNDARY -- determine if this line is a MIME boundary & its type
875**
876** Parameters:
877** line -- the input line.
878** boundaries -- the set of currently pending boundaries.
879**
880** Returns:
881** MBT_NOTSEP -- if this is not a separator line
882** MBT_INTERMED -- if this is an intermediate separator
883** MBT_FINAL -- if this is a final boundary
884** MBT_SYNTAX -- if this is a boundary for the wrong
885** enclosure -- i.e., a syntax error.
886*/
887
888static int
889mimeboundary(line, boundaries)
890 register char *line;
891 char **boundaries;
892{
893 int type = MBT_NOTSEP;
894 int i;
895 int savec;
896
897 if (line[0] != '-' || line[1] != '-' || boundaries == NULL)
898 return MBT_NOTSEP;
899 i = strlen(line);
900 if (i > 0 && line[i - 1] == '\n')
901 i--;
902
903 /* strip off trailing whitespace */
904 while (i > 0 && (line[i - 1] == ' ' || line[i - 1] == '\t'
905#if _FFR_MIME_CR_OK
906 || line[i - 1] == '\r'
907#endif /* _FFR_MIME_CR_OK */
908 ))
909 i--;
910 savec = line[i];
911 line[i] = '\0';
912
913 if (tTd(43, 5))
914 sm_dprintf("mimeboundary: line=\"%s\"... ", line);
915
916 /* check for this as an intermediate boundary */
917 if (isboundary(&line[2], boundaries) >= 0)
918 type = MBT_INTERMED;
919 else if (i > 2 && strncmp(&line[i - 2], "--", 2) == 0)
920 {
921 /* check for a final boundary */
922 line[i - 2] = '\0';
923 if (isboundary(&line[2], boundaries) >= 0)
924 type = MBT_FINAL;
925 line[i - 2] = '-';
926 }
927
928 line[i] = savec;
929 if (tTd(43, 5))
930 sm_dprintf("%s\n", MimeBoundaryNames[type]);
931 return type;
932}
933/*
934** DEFCHARSET -- return default character set for message
935**
936** The first choice for character set is for the mailer
937** corresponding to the envelope sender. If neither that
938** nor the global configuration file has a default character
939** set defined, return "unknown-8bit" as recommended by
940** RFC 1428 section 3.
941**
942** Parameters:
943** e -- the envelope for this message.
944**
945** Returns:
946** The default character set for that mailer.
947*/
948
949char *
950defcharset(e)
951 register ENVELOPE *e;
952{
953 if (e != NULL && e->e_from.q_mailer != NULL &&
954 e->e_from.q_mailer->m_defcharset != NULL)
955 return e->e_from.q_mailer->m_defcharset;
956 if (DefaultCharSet != NULL)
957 return DefaultCharSet;
958 return "unknown-8bit";
959}
960/*
961** ISBOUNDARY -- is a given string a currently valid boundary?
962**
963** Parameters:
964** line -- the current input line.
965** boundaries -- the list of valid boundaries.
966**
967** Returns:
968** The index number in boundaries if the line is found.
969** -1 -- otherwise.
970**
971*/
972
973static int
974isboundary(line, boundaries)
975 char *line;
976 char **boundaries;
977{
978 register int i;
979
980 for (i = 0; i <= MAXMIMENESTING && boundaries[i] != NULL; i++)
981 {
982 if (strcmp(line, boundaries[i]) == 0)
983 return i;
984 }
985 return -1;
986}
987#endif /* MIME8TO7 */
988
989#if MIME7TO8
990static int mime_fromqp __P((unsigned char *, unsigned char **, int));
991
992/*
993** MIME7TO8 -- output 7 bit encoded MIME body in 8 bit format
994**
995** This is a hack. Supports translating the two 7-bit body-encodings
996** (quoted-printable and base64) to 8-bit coded bodies.
997**
998** There is not much point in supporting multipart here, as the UA
999** will be able to deal with encoded MIME bodies if it can parse MIME
1000** multipart messages.
1001**
1002** Note also that we won't be called unless it is a text/plain MIME
1003** message, encoded base64 or QP and mailer flag '9' has been defined
1004** on mailer.
1005**
1006** Contributed by Marius Olaffson <marius@rhi.hi.is>.
1007**
1008** Parameters:
1009** mci -- mailer connection information.
1010** header -- the header for this body part.
1011** e -- envelope.
1012**
1013** Returns:
1014** true iff body was written successfully
1015*/
1016
1017static char index_64[128] =
1018{
1019 -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
1020 -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
1021 -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,62, -1,-1,-1,63,
1022 52,53,54,55, 56,57,58,59, 60,61,-1,-1, -1,-1,-1,-1,
1023 -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10, 11,12,13,14,
1024 15,16,17,18, 19,20,21,22, 23,24,25,-1, -1,-1,-1,-1,
1025 -1,26,27,28, 29,30,31,32, 33,34,35,36, 37,38,39,40,
1026 41,42,43,44, 45,46,47,48, 49,50,51,-1, -1,-1,-1,-1
1027};
1028
1029# define CHAR64(c) (((c) < 0 || (c) > 127) ? -1 : index_64[(c)])
1030
1031bool
1032mime7to8(mci, header, e)
1033 register MCI *mci;
1034 HDR *header;
1035 register ENVELOPE *e;
1036{
1037 int pxflags, blen;
1038 register char *p;
1039 char *cte;
1040 char **pvp;
1041 unsigned char *fbufp;
1042 char buf[MAXLINE];
1043 unsigned char fbuf[MAXLINE + 1];
1044 char pvpbuf[MAXLINE];
1045 extern unsigned char MimeTokenTab[256];
1046
1047 p = hvalue("Content-Transfer-Encoding", header);
1048 if (p == NULL ||
1049 (pvp = prescan(p, '\0', pvpbuf, sizeof(pvpbuf), NULL,
1050 MimeTokenTab, false)) == NULL ||
1051 pvp[0] == NULL)
1052 {
1053 /* "can't happen" -- upper level should have caught this */
1054 syserr("mime7to8: unparsable CTE %s", p == NULL ? "<NULL>" : p);
1055
1056 /* avoid bounce loops */
1057 e->e_flags |= EF_DONT_MIME;
1058
1059 /* cheap failsafe algorithm -- should work on text/plain */
1060 if (p != NULL)
1061 {
1062 (void) sm_snprintf(buf, sizeof(buf),
1063 "Content-Transfer-Encoding: %s", p);
1064 if (!putline(buf, mci))
1065 goto writeerr;
1066 }
1067 if (!putline("", mci))
1068 goto writeerr;
1069 mci->mci_flags &= ~MCIF_INHEADER;
1070 while ((blen = sm_io_fgets(e->e_dfp, SM_TIME_DEFAULT, buf,
1071 sizeof(buf))) >= 0)
1072 {
1073 if (!putxline(buf, blen, mci, PXLF_MAPFROM))
1074 goto writeerr;
1075 }
1076 return true;
1077 }
1078 cataddr(pvp, NULL, buf, sizeof(buf), '\0', false);
1079 cte = sm_rpool_strdup_x(e->e_rpool, buf);
1080
1081 mci->mci_flags |= MCIF_INHEADER;
1082 if (!putline("Content-Transfer-Encoding: 8bit", mci))
1083 goto writeerr;
1084 (void) sm_snprintf(buf, sizeof(buf),
1085 "X-MIME-Autoconverted: from %.200s to 8bit by %s id %s",
1086 cte, MyHostName, e->e_id);
1087 if (!putline(buf, mci) || !putline("", mci))
1088 goto writeerr;
1089 mci->mci_flags &= ~MCIF_INHEADER;
1090
1091 /*
1092 ** Translate body encoding to 8-bit. Supports two types of
1093 ** encodings; "base64" and "quoted-printable". Assume qp if
1094 ** it is not base64.
1095 */
1096
1097 pxflags = PXLF_MAPFROM;
1098 if (sm_strcasecmp(cte, "base64") == 0)
1099 {
1100 int c1, c2, c3, c4;
1101
1102 fbufp = fbuf;
1103 while ((c1 = sm_io_getc(e->e_dfp, SM_TIME_DEFAULT)) !=
1104 SM_IO_EOF)
1105 {
1106 if (isascii(c1) && isspace(c1))
1107 continue;
1108
1109 do
1110 {
1111 c2 = sm_io_getc(e->e_dfp, SM_TIME_DEFAULT);
1112 } while (isascii(c2) && isspace(c2));
1113 if (c2 == SM_IO_EOF)
1114 break;
1115
1116 do
1117 {
1118 c3 = sm_io_getc(e->e_dfp, SM_TIME_DEFAULT);
1119 } while (isascii(c3) && isspace(c3));
1120 if (c3 == SM_IO_EOF)
1121 break;
1122
1123 do
1124 {
1125 c4 = sm_io_getc(e->e_dfp, SM_TIME_DEFAULT);
1126 } while (isascii(c4) && isspace(c4));
1127 if (c4 == SM_IO_EOF)
1128 break;
1129
1130 if (c1 == '=' || c2 == '=')
1131 continue;
1132 c1 = CHAR64(c1);
1133 c2 = CHAR64(c2);
1134
1135#if MIME7TO8_OLD
1136#define CHK_EOL if (*--fbufp != '\n' || (fbufp > fbuf && *--fbufp != '\r')) \
1137 ++fbufp;
1138#else /* MIME7TO8_OLD */
1139#define CHK_EOL if (*--fbufp != '\n' || (fbufp > fbuf && *--fbufp != '\r')) \
1140 { \
1141 ++fbufp; \
1142 pxflags |= PXLF_NOADDEOL; \
1143 }
1144#endif /* MIME7TO8_OLD */
1145
1146#define PUTLINE64 \
1147 do \
1148 { \
1149 if (*fbufp++ == '\n' || fbufp >= &fbuf[MAXLINE]) \
1150 { \
1151 CHK_EOL; \
1152 if (!putxline((char *) fbuf, fbufp - fbuf, mci, pxflags)) \
1153 goto writeerr; \
1154 pxflags &= ~PXLF_NOADDEOL; \
1155 fbufp = fbuf; \
1156 } \
1157 } while (0)
1158
1159 *fbufp = (c1 << 2) | ((c2 & 0x30) >> 4);
1160 PUTLINE64;
1161 if (c3 == '=')
1162 continue;
1163 c3 = CHAR64(c3);
1164 *fbufp = ((c2 & 0x0f) << 4) | ((c3 & 0x3c) >> 2);
1165 PUTLINE64;
1166 if (c4 == '=')
1167 continue;
1168 c4 = CHAR64(c4);
1169 *fbufp = ((c3 & 0x03) << 6) | c4;
1170 PUTLINE64;
1171 }
1172 }
1173 else
1174 {
1175 int off;
1176
1177 /* quoted-printable */
1178 pxflags |= PXLF_NOADDEOL;
1179 fbufp = fbuf;
1180 while (sm_io_fgets(e->e_dfp, SM_TIME_DEFAULT, buf,
1181 sizeof(buf)) >= 0)
1182 {
1183 off = mime_fromqp((unsigned char *) buf, &fbufp,
1184 &fbuf[MAXLINE] - fbufp);
1185again:
1186 if (off < -1)
1187 continue;
1188
1189 if (fbufp - fbuf > 0)
1190 {
1191 if (!putxline((char *) fbuf, fbufp - fbuf - 1,
1192 mci, pxflags))
1193 goto writeerr;
1194 }
1195 fbufp = fbuf;
1196 if (off >= 0 && buf[off] != '\0')
1197 {
1198 off = mime_fromqp((unsigned char *) (buf + off),
1199 &fbufp,
1200 &fbuf[MAXLINE] - fbufp);
1201 goto again;
1202 }
1203 }
1204 }
1205
1206 /* force out partial last line */
1207 if (fbufp > fbuf)
1208 {
1209 *fbufp = '\0';
1210 if (!putxline((char *) fbuf, fbufp - fbuf, mci, pxflags))
1211 goto writeerr;
1212 }
1213
1214 /*
1215 ** The decoded text may end without an EOL. Since this function
1216 ** is only called for text/plain MIME messages, it is safe to
1217 ** add an extra one at the end just in case. This is a hack,
1218 ** but so is auto-converting MIME in the first place.
1219 */
1220
1221 if (!putline("", mci))
1222 goto writeerr;
1223
1224 if (tTd(43, 3))
1225 sm_dprintf("\t\t\tmime7to8 => %s to 8bit done\n", cte);
1226 return true;
1227
1228 writeerr:
1229 return false;
1230}
1231/*
1232** The following is based on Borenstein's "codes.c" module, with simplifying
1233** changes as we do not deal with multipart, and to do the translation in-core,
1234** with an attempt to prevent overrun of output buffers.
1235**
1236** What is needed here are changes to defend this code better against
1237** bad encodings. Questionable to always return 0xFF for bad mappings.
1238*/
1239
1240static char index_hex[128] =
1241{
1242 -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
1243 -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
1244 -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
1245 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,-1,-1, -1,-1,-1,-1,
1246 -1,10,11,12, 13,14,15,-1, -1,-1,-1,-1, -1,-1,-1,-1,
1247 -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
1248 -1,10,11,12, 13,14,15,-1, -1,-1,-1,-1, -1,-1,-1,-1,
1249 -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1
1250};
1251
1252# define HEXCHAR(c) (((c) < 0 || (c) > 127) ? -1 : index_hex[(c)])
1253
1254/*
1255** MIME_FROMQP -- decode quoted printable string
1256**
1257** Parameters:
1258** infile -- input (encoded) string
1259** outfile -- output string
1260** maxlen -- size of output buffer
1261**
1262** Returns:
1263** -2 if decoding failure
1264** -1 if infile completely decoded into outfile
1265** >= 0 is the position in infile decoding
1266** reached before maxlen was reached
1267*/
1268
1269static int
1270mime_fromqp(infile, outfile, maxlen)
1271 unsigned char *infile;
1272 unsigned char **outfile;
1273 int maxlen; /* Max # of chars allowed in outfile */
1274{
1275 int c1, c2;
1276 int nchar = 0;
1277 unsigned char *b;
1278
1279 /* decrement by one for trailing '\0', at least one other char */
1280 if (--maxlen < 1)
1281 return 0;
1282
1283 b = infile;
1284 while ((c1 = *infile++) != '\0' && nchar < maxlen)
1285 {
1286 if (c1 == '=')
1287 {
1288 if ((c1 = *infile++) == '\0')
1289 break;
1290
1291 if (c1 == '\n' || (c1 = HEXCHAR(c1)) == -1)
1292 {
1293 /* ignore it and the rest of the buffer */
1294 return -2;
1295 }
1296 else
1297 {
1298 do
1299 {
1300 if ((c2 = *infile++) == '\0')
1301 {
1302 c2 = -1;
1303 break;
1304 }
1305 } while ((c2 = HEXCHAR(c2)) == -1);
1306
1307 if (c2 == -1)
1308 break;
1309 nchar++;
1310 *(*outfile)++ = c1 << 4 | c2;
1311 }
1312 }
1313 else
1314 {
1315 nchar++;
1316 *(*outfile)++ = c1;
1317 if (c1 == '\n')
1318 break;
1319 }
1320 }
1321 *(*outfile)++ = '\0';
1322 if (nchar >= maxlen)
1323 return (infile - b - 1);
1324 return -1;
1325}
1326#endif /* MIME7TO8 */