1 /* $Cambridge: exim/src/src/parse.c,v 1.2 2004/11/17 15:21:10 ph10 Exp $ */
3 /*************************************************
4 * Exim - an Internet mail transport agent *
5 *************************************************/
7 /* Copyright (c) University of Cambridge 1995 - 2004 */
8 /* See the file NOTICE for conditions of use and distribution. */
10 /* Functions for parsing addresses */
16 static uschar *last_comment_position;
20 /* In stand-alone mode, provide a replacement for deliver_make_addr()
21 and rewrite_address[_qualify]() so as to avoid having to drag in too much
22 redundant apparatus. */
26 address_item *deliver_make_addr(uschar *address, BOOL copy)
28 address_item *addr = store_get(sizeof(address_item));
31 addr->address = address;
35 uschar *rewrite_address(uschar *recipient, BOOL dummy1, BOOL dummy2, rewrite_rule
41 uschar *rewrite_address_qualify(uschar *recipient, BOOL dummy1)
51 /*************************************************
52 * Find the end of an address *
53 *************************************************/
55 /* Scan over a string looking for the termination of an address at a comma,
56 or end of the string. It's the source-routed addresses which cause much pain
57 here. Although Exim ignores source routes, it must recognize such addresses, so
58 we cannot get rid of this logic.
61 s pointer to the start of an address
62 nl_ends if TRUE, '\n' terminates an address
64 Returns: pointer past the end of the address
65 (i.e. points to null or comma)
69 parse_find_address_end(uschar *s, BOOL nl_ends)
71 BOOL source_routing = *s == '@';
72 int no_term = source_routing? 1 : 0;
74 while (*s != 0 && (*s != ',' || no_term > 0) && (*s != '\n' || !nl_ends))
76 /* Skip single quoted characters. Strictly these should not occur outside
77 quoted strings in RFC 822 addresses, but they can in RFC 821 addresses. Pity
78 about the lack of consistency, isn't it? */
80 if (*s == '\\' && s[1] != 0) s += 2;
82 /* Skip quoted items that are not inside brackets. Note that
83 quoted pairs are allowed inside quoted strings. */
87 while (*(++s) != 0 && (*s != '\n' || !nl_ends))
89 if (*s == '\\' && s[1] != 0) s++;
90 else if (*s == '\"') { s++; break; }
94 /* Skip comments, which may include nested brackets, but quotes
95 are not recognized inside comments, though quoted pairs are. */
100 while (*(++s) != 0 && (*s != '\n' || !nl_ends))
102 if (*s == '\\' && s[1] != 0) s++;
103 else if (*s == '(') level++;
104 else if (*s == ')' && --level <= 0) { s++; break; }
108 /* Non-special character; just advance. Passing the colon in a source
109 routed address means that any subsequent comma or colon may terminate unless
110 inside angle brackets. */
116 source_routing = s[1] == '@';
117 no_term = source_routing? 2 : 1;
119 else if (*s == '>') no_term--;
120 else if (source_routing && *s == ':') no_term--;
130 /*************************************************
131 * Find last @ in an address *
132 *************************************************/
134 /* This function is used when we have something that may not qualified. If we
135 know it's qualified, searching for the rightmost '@' is sufficient. Here we
136 have to be a bit more clever than just a plain search, in order to handle
137 unqualified local parts like "thing@thong" correctly. Since quotes may not
138 legally be part of a domain name, we can give up on hitting the first quote
139 when searching from the right. Now that the parsing also permits the RFC 821
140 form of address, where quoted-pairs are allowed in unquoted local parts, we
141 must take care to handle that too.
143 Argument: pointer to an address, possibly unqualified
144 Returns: pointer to the last @ in an address, or NULL if none
148 parse_find_at(uschar *s)
150 uschar *t = s + Ustrlen(s);
155 int backslash_count = 0;
157 while (tt > s && *tt-- == '\\') backslash_count++;
158 if ((backslash_count & 1) == 0) return t;
160 else if (*t == '\"') return NULL;
168 /***************************************************************************
169 * In all the functions below that read a particular object type from *
170 * the input, return the new value of the pointer s (the first argument), *
171 * and put the object into the store pointed to by t (the second argument), *
172 * adding a terminating zero. If no object is found, t will point to zero *
174 ***************************************************************************/
177 /*************************************************
178 * Skip white space and comment *
179 *************************************************/
183 (2) If uschar not '(', return.
184 (3) Skip till matching ')', not counting any characters
186 (4) Move past ')' and goto (1).
188 The start of the last potential comment position is remembered to
189 make it possible to ignore comments at the end of compound items.
191 Argument: current character pointer
192 Regurns: new character pointer
196 skip_comment(uschar *s)
198 last_comment_position = s;
202 while (isspace(*s)) s++;
203 if (*s != '(') break;
205 while((c = *(++s)) != 0)
207 if (c == '(') level++;
208 else if (c == ')') { if (--level <= 0) { s++; break; } }
209 else if (c == '\\' && s[1] != 0) s++;
217 /*************************************************
219 *************************************************/
221 /* A domain is a sequence of subdomains, separated by dots. See comments below
222 for detailed syntax of the subdomains.
224 If allow_domain_literals is TRUE, a "domain" may also be an IP address enclosed
225 in []. Make sure the output is set to the null string if there is a syntax
226 error as well as if there is no domain at all.
229 s current character pointer
230 t where to put the domain
231 errorptr put error message here on failure (*t will be 0 on exit)
233 Returns: new character pointer
237 read_domain(uschar *s, uschar *t, uschar **errorptr)
242 /* Handle domain literals if permitted. An RFC 822 domain literal may contain
243 any character except [ ] \, including linear white space, and may contain
244 quoted characters. However, RFC 821 restricts literals to being dot-separated
245 3-digit numbers, and we make the obvious extension for IPv6. Go for a sequence
246 of digits and dots (hex digits and colons for IPv6) here; later this will be
247 checked for being a syntactically valid IP address if it ever gets to a router.
249 If IPv6 is supported, allow both the formal form, with IPV6: at the start, and
250 the informal form without it, and accept IPV4: as well, 'cause someone will use
251 it sooner or later. */
258 if (strncmpic(s, US"IPv6:", 5) == 0 || strncmpic(s, US"IPv4:", 5) == 0)
264 while (*s == '.' || *s == ':' || isxdigit(*s)) *t++ = *s++;
267 while (*s == '.' || isdigit(*s)) *t++ = *s++;
270 if (*s == ']') *t++ = *s++; else
272 *errorptr = US"malformed domain literal";
276 if (!allow_domain_literals)
278 *errorptr = US"domain literals not allowed";
282 return skip_comment(s);
285 /* Handle a proper domain, which is a sequence of dot-separated atoms. Remove
286 trailing dots if strip_trailing_dot is set. A subdomain is an atom.
288 An atom is a sequence of any characters except specials, space, and controls.
289 The specials are ( ) < > @ , ; : \ " . [ and ]. This is the rule for RFC 822
290 and its successor (RFC 2822). However, RFC 821 and its successor (RFC 2821) is
291 tighter, allowing only letters, digits, and hyphens, not starting with a
294 There used to be a global flag that got set when checking addresses that came
295 in over SMTP and which should therefore should be checked according to the
296 stricter rule. However, it seems silly to make the distinction, because I don't
297 suppose anybody ever uses local domains that are 822-compliant and not
298 821-compliant. Furthermore, Exim now has additional data on the spool file line
299 after an address (after "one_time" processing), and it makes use of a #
300 character to delimit it. When I wrote that code, I forgot about this 822-domain
301 stuff, and assumed # could never appear in a domain.
303 So the old code is now cut out for Release 4.11 onwards, on 09-Aug-02. In a few
304 years, when we are sure this isn't actually causing trouble, throw it away.
306 March 2003: the story continues: There is a camp that is arguing for the use of
307 UTF-8 in domain names as the way to internationalization, and other MTAs
308 support this. Therefore, we now have a flag that permits the use of characters
309 with values greater than 127, encoded in UTF-8, in subdomains, so that Exim can
310 be used experimentally in this way. */
316 /*********************
319 if (*s != '-') while (isalnum(*s) || *s == '-') *t++ = *s++;
322 while (!mac_iscntrl_or_special(*s)) *t++ = *s++;
323 *********************/
327 /* Only letters, digits, and hyphens */
329 if (!allow_utf8_domains)
331 while (isalnum(*s) || *s == '-') *t++ = *s++;
334 /* Permit legal UTF-8 characters to be included */
339 if (isalnum(*s) || *s == '-') /* legal ascii characters */
344 if ((*s & 0xc0) != 0xc0) break; /* not start of UTF-8 character */
346 for (i = 1; i < 6; i++) /* i is the number of additional bytes */
348 if ((d & 0x80) == 0) break;
351 if (i == 6) goto BAD_UTF8; /* invalid UTF-8 */
352 *t++ = *s++; /* leading UTF-8 byte */
353 while (i-- > 0) /* copy and check remainder */
355 if ((*s & 0xc0) != 0x80)
358 *errorptr = US"invalid UTF-8 byte sequence";
364 } /* End of loop for UTF-8 character */
365 } /* End of subdomain */
370 if (t == tsave) /* empty component */
372 if (strip_trailing_dot && t > tt && *s != '.') t[-1] = 0; else
374 *errorptr = US"domain missing or malformed";
380 if (*s != '.') break;
390 /*************************************************
391 * Read a local-part *
392 *************************************************/
394 /* A local-part is a sequence of words, separated by periods. A null word
395 between dots is not strictly allowed but apparently many mailers permit it,
396 so, sigh, better be compatible. Even accept a trailing dot...
398 A <word> is either a quoted string, or an <atom>, which is a sequence
399 of any characters except specials, space, and controls. The specials are
400 ( ) < > @ , ; : \ " . [ and ]. In RFC 822, a single quoted character, (a
401 quoted-pair) is not allowed in a word. However, in RFC 821, it is permitted in
402 the local part of an address. Rather than have separate parsing functions for
403 the different cases, take the liberal attitude always. At least one MUA is
404 happy to recognize this case; I don't know how many other programs do.
407 s current character pointer
408 t where to put the local part
409 error where to point error text
410 allow_null TRUE if an empty local part is not an error
412 Returns: new character pointer
416 read_local_part(uschar *s, uschar *t, uschar **error, BOOL allow_null)
426 /* Handle a quoted string */
431 while ((c = *(++s)) != 0 && c != '\"')
434 if (c == '\\' && s[1] != 0) *t++ = *(++s);
443 *error = US"unmatched doublequote in local part";
448 /* Handle an atom, but allow quoted pairs within it. */
450 else while (!mac_iscntrl_or_special(*s) || *s == '\\')
453 if (c == '\\' && *s != 0) *t++ = *s++;
456 /* Terminate the word and skip subsequent comment */
461 /* If we have read a null component at this point, give an error unless it is
462 terminated by a dot - an extension to RFC 822 - or if it is the first
463 component of the local part and an empty local part is permitted, in which
464 case just return normally. */
466 if (t == tsave && *s != '.')
468 if (t == tt && !allow_null)
469 *error = US"missing or malformed local part";
473 /* Anything other than a dot terminates the local part. Treat multiple dots
474 as a single dot, as this seems to be a common extension. */
476 if (*s != '.') break;
477 do { *t++ = *s++; } while (*s == '.');
484 /*************************************************
485 * Read route part of route-addr *
486 *************************************************/
488 /* The pointer is at the initial "@" on entry. Return it following the
489 terminating colon. Exim no longer supports the use of source routes, but it is
490 required to accept the syntax.
493 s current character pointer
494 t where to put the route
495 errorptr where to put an error message
497 Returns: new character pointer
501 read_route(uschar *s, uschar *t, uschar **errorptr)
509 s = read_domain(s+1, t, errorptr);
510 if (*t == 0) return s;
511 t += Ustrlen((const uschar *)t);
512 if (*s != ',') break;
518 if (*s == ':') *t++ = *s++;
520 /* If there is no colon, and there were no commas, the most likely error
521 is in fact a missing local part in the address rather than a missing colon
524 else *errorptr = commas?
525 US"colon expected after route list" :
528 /* Terminate the route and return */
531 return skip_comment(s);
536 /*************************************************
538 *************************************************/
540 /* Addr-spec is local-part@domain. We make the domain optional -
541 the expected terminator for the whole thing is passed to check this.
542 This function is called only when we know we have a route-addr.
545 s current character pointer
546 t where to put the addr-spec
547 term expected terminator (0 or >)
548 errorptr where to put an error message
549 domainptr set to point to the start of the domain
551 Returns: new character pointer
555 read_addr_spec(uschar *s, uschar *t, int term, uschar **errorptr,
558 s = read_local_part(s, t, errorptr, FALSE);
559 if (*errorptr == NULL)
564 *errorptr = string_sprintf("\"@\" or \".\" expected after \"%s\"", t);
567 t += Ustrlen((const uschar *)t);
570 s = read_domain(s, t, errorptr);
579 /*************************************************
580 * Extract operative address *
581 *************************************************/
583 /* This function extracts an operative address from a full RFC822 mailbox and
584 returns it in a piece of dynamic store. We take the easy way and get a piece
585 of store the same size as the input, and then copy into it whatever is
586 necessary. If we cannot find a valid address (syntax error), return NULL, and
587 point the error pointer to the reason. The arguments "start" and "end" are used
588 to return the offsets of the first and one past the last characters in the
589 original mailbox of the address that has been extracted, to aid in re-writing.
590 The argument "domain" is set to point to the first character after "@" in the
591 final part of the returned address, or zero if there is no @.
593 Exim no longer supports the use of source routed addresses (those of the form
594 @domain,...:route_addr). It recognizes the syntax, but collapses such addresses
595 down to their final components. Formerly, collapse_source_routes had to be set
596 to achieve this effect. RFC 1123 allows collapsing with MAY, while the revision
597 of RFC 821 had increased this to SHOULD, so I've gone for it, because it makes
598 a lot of code elsewhere in Exim much simpler.
600 There are some special fudges here for handling RFC 822 group address notation
601 which may appear in certain headers. If the flag parse_allow_group is set
602 TRUE and parse_found_group is FALSE when this function is called, an address
603 which is the start of a group (i.e. preceded by a phrase and a colon) is
604 recognized; the phrase is ignored and the flag parse_found_group is set. If
605 this flag is TRUE at the end of an address, then if an extraneous semicolon is
606 found, it is ignored and the flag is cleared. This logic is used only when
607 scanning through addresses in headers, either to fulfil the -t option or for
608 rewriting or checking header syntax.
611 mailbox points to the RFC822 mailbox
612 errorptr where to point an error message
613 start set to start offset in mailbox
614 end set to end offset in mailbox
615 domain set to domain offset in result, or 0 if no domain present
616 allow_null allow <> if TRUE
618 Returns: points to the extracted address, or NULL on error
621 #define FAILED(s) { *errorptr = s; goto PARSE_FAILED; }
624 parse_extract_address(uschar *mailbox, uschar **errorptr, int *start, int *end,
625 int *domain, BOOL allow_null)
627 uschar *yield = store_get(Ustrlen(mailbox) + 1);
628 uschar *startptr, *endptr;
629 uschar *s = (uschar *)mailbox;
630 uschar *t = (uschar *)yield;
634 /* At the start of the string we expect either an addr-spec or a phrase
635 preceding a <route-addr>. If groups are allowed, we might also find a phrase
636 preceding a colon and an address. If we find an initial word followed by
637 a dot, strict interpretation of the RFC would cause it to be taken
638 as the start of an addr-spec. However, many mailers break the rules
639 and use addresses of the form "a.n.other <ano@somewhere>" and so we
642 RESTART: /* Come back here after passing a group name */
645 startptr = s; /* In case addr-spec */
646 s = read_local_part(s, t, errorptr, TRUE); /* Dot separated words */
647 if (*errorptr != NULL) goto PARSE_FAILED;
649 /* If the terminator is neither < nor @ then the format of the address
650 must either be a bare local-part (we are now at the end), or a phrase
651 followed by a route-addr (more words must follow). */
653 if (*s != '@' && *s != '<')
655 if (*s == 0 || *s == ';')
657 if (*t == 0) FAILED(US"empty address");
658 endptr = last_comment_position;
659 goto PARSE_SUCCEEDED; /* Bare local part */
662 /* Expect phrase route-addr, or phrase : if groups permitted, but allow
663 dots in the phrase; complete the loop only when '<' or ':' is encountered -
664 end of string will produce a null local_part and therefore fail. We don't
665 need to keep updating t, as the phrase isn't to be kept. */
667 while (*s != '<' && (!parse_allow_group || *s != ':'))
669 s = read_local_part(s, t, errorptr, FALSE);
670 if (*errorptr != NULL)
672 *errorptr = string_sprintf("%s (expected word or \"<\")", *errorptr);
679 parse_found_group = TRUE;
680 parse_allow_group = FALSE;
685 /* Assert *s == '<' */
688 /* At this point the next character is either '@' or '<'. If it is '@', only a
689 single local-part has previously been read. An angle bracket signifies the
690 start of an <addr-spec>. Throw away anything we have saved so far before
691 processing it. Note that this is "if" rather than "else if" because it's also
692 used after reading a preceding phrase.
694 There are a lot of broken sendmails out there that put additional pairs of <>
695 round <route-addr>s. If strip_excess_angle_brackets is set, allow any number of
696 them, as long as they match. */
700 uschar *domainptr = yield;
701 BOOL source_routed = FALSE;
702 int bracket_count = 1;
705 if (strip_excess_angle_brackets)
706 while (*s == '<') { bracket_count++; s++; }
712 /* Read an optional series of routes, each of which is a domain. They
713 are separated by commas and terminated by a colon. However, we totally ignore
714 such routes (RFC 1123 says we MAY, and the revision of RFC 821 says we
719 s = read_route(s, t, errorptr);
720 if (*errorptr != NULL) goto PARSE_FAILED;
721 *t = 0; /* Ensure route is ignored - probably overkill */
722 source_routed = TRUE;
725 /* Now an addr-spec, terminated by '>'. If there is no preceding route,
726 we must allow an empty addr-spec if allow_null is TRUE, to permit the
727 address "<>" in some circumstances. A source-routed address MUST have
728 a domain in the final part. */
730 if (allow_null && !source_routed && *s == '>')
737 s = read_addr_spec(s, t, '>', errorptr, &domainptr);
738 if (*errorptr != NULL) goto PARSE_FAILED;
739 *domain = domainptr - yield;
740 if (source_routed && *domain == 0)
741 FAILED(US"domain missing in source-routed address");
745 if (*errorptr != NULL) goto PARSE_FAILED;
746 while (bracket_count-- > 0) if (*s++ != '>')
748 *errorptr = (s[-1] == 0)? US"'>' missing at end of address" :
749 string_sprintf("malformed address: %.32s may not follow %.*s",
750 s-1, s - (uschar *)mailbox - 1, mailbox);
757 /* Hitting '@' after the first local-part means we have definitely got an
758 addr-spec, on a strict reading of the RFC, and the rest of the string
759 should be the domain. However, for flexibility we allow for a route-address
760 not enclosed in <> as well, which is indicated by an empty first local
761 part preceding '@'. The source routing is, however, ignored. */
765 uschar *domainptr = yield;
766 s = read_route(s, t, errorptr);
767 if (*errorptr != NULL) goto PARSE_FAILED;
768 *t = 0; /* Ensure route is ignored - probably overkill */
769 s = read_addr_spec(s, t, 0, errorptr, &domainptr);
770 if (*errorptr != NULL) goto PARSE_FAILED;
771 *domain = domainptr - yield;
772 endptr = last_comment_position;
773 if (*domain == 0) FAILED(US"domain missing in source-routed address");
776 /* This is the strict case of local-part@domain. */
780 t += Ustrlen((const uschar *)t);
783 s = read_domain(s, t, errorptr);
784 if (*t == 0) goto PARSE_FAILED;
785 endptr = last_comment_position;
788 /* Use goto to get here from the bare local part case. Arrive by falling
789 through for other cases. Endptr may have been moved over whitespace, so
790 move it back past white space if necessary. */
795 if (parse_found_group && *s == ';')
797 parse_found_group = FALSE;
798 parse_allow_group = TRUE;
802 *errorptr = string_sprintf("malformed address: %.32s may not follow %.*s",
803 s, s - (uschar *)mailbox, mailbox);
807 *start = startptr - (uschar *)mailbox; /* Return offsets */
808 while (isspace(endptr[-1])) endptr--;
809 *end = endptr - (uschar *)mailbox;
811 /* Although this code has no limitation on the length of address extracted,
812 other parts of Exim may have limits, and in any case, RFC 2821 limits local
813 parts to 64 and domains to 255, so we do a check here, giving an error if the
814 address is ridiculously long. */
816 if (*end - *start > ADDRESS_MAXLENGTH)
818 *errorptr = string_sprintf("address is ridiculously long: %.64s...", yield);
822 return (uschar *)yield;
824 /* Use goto (via the macro FAILED) to get to here from a variety of places.
825 We might have an empty address in a group - the caller can choose to ignore
826 this. We must, however, keep the flags correct. */
829 if (parse_found_group && *s == ';')
831 parse_found_group = FALSE;
832 parse_allow_group = TRUE;
841 /*************************************************
842 * Quote according to RFC 2047 *
843 *************************************************/
845 /* This function is used for quoting text in headers according to RFC 2047.
846 If the only characters that strictly need quoting are spaces, we return the
847 original string, unmodified. If a quoted string is too long for the buffer, it
848 is truncated. (This shouldn't happen: this is normally handling short strings.)
850 Hmmph. As always, things get perverted for other uses. This function was
851 originally for the "phrase" part of addresses. Now it is being used for much
852 longer texts in ACLs and via the ${rfc2047: expansion item. This means we have
853 to check for overlong "encoded-word"s and split them. November 2004.
856 string the string to quote - already checked to contain non-printing
858 len the length of the string
859 charset the name of the character set; NULL => iso-8859-1
860 buffer the buffer to put the answer in
861 buffer_size the size of the buffer
863 Returns: pointer to the original string, if no quoting needed, or
864 pointer to buffer containing the quoted string, or
865 a pointer to "String too long" if the buffer can't even hold
870 parse_quote_2047(uschar *string, int len, uschar *charset, uschar *buffer,
878 if (charset == NULL) charset = US"iso-8859-1";
880 /* We don't expect this to fail! */
882 if (!string_format(buffer, buffer_size, "=?%s?Q?", charset))
883 return US"String too long";
885 hlen = Ustrlen(buffer);
889 for (; len > 0; len--)
892 if (t > buffer + buffer_size - hlen - 8) break;
900 Ustrncpy(p, buffer, hlen);
904 if (ch < 33 || ch > 126 ||
905 Ustrchr("?=()<>@,;:\\\".[]_", ch) != NULL)
907 if (ch == ' ') *t++ = '_'; else
909 sprintf(CS t, "=%02X", ch);
921 return coded? buffer : string;
927 /*************************************************
928 * Fix up an RFC 822 "phrase" *
929 *************************************************/
931 /* This function is called to repair any syntactic defects in the "phrase" part
932 of an RFC822 address. In particular, it is applied to the user's name as read
933 from the passwd file when accepting a local message, and to the data from the
936 If the string contains existing quoted strings or comments containing
937 freestanding quotes, then we just quote those bits that need quoting -
938 otherwise it would get awfully messy and probably not look good. If not, we
939 quote the whole thing if necessary. Thus
941 John Q. Smith => "John Q. Smith"
942 John "Jack" Smith => John "Jack" Smith
943 John "Jack" Q. Smith => John "Jack" "Q." Smith
944 John (Jack) Q. Smith => "John (Jack) Q. Smith"
945 John ("Jack") Q. Smith => John ("Jack") "Q." Smith
947 John (\"Jack\") Q. Smith => "John (\"Jack\") Q. Smith"
949 Sheesh! This is tedious code. It is a great pity that the syntax of RFC822 is
952 August 2000: Additional code added:
954 Previously, non-printing characters were turned into question marks, which do
955 not need to be quoted.
957 Now, a different tactic is used if there are any non-printing ASCII
958 characters. The encoding method from RFC 2047 is used, assuming iso-8859-1 as
961 We *could* use this for all cases, getting rid of the messy original code,
962 but leave it for now. It would complicate simple cases like "John Q. Smith".
964 The result is passed back in the buffer; it is usually going to be added to
965 some other string. In order to be sure there is going to be no overflow,
966 restrict the length of the input to 1/4 of the buffer size - this allows for
967 every single character to be quoted or encoded without overflowing, and that
968 wouldn't happen because of amalgamation. If the phrase is too long, return a
972 phrase an RFC822 phrase
973 len the length of the phrase
974 buffer a buffer to put the result in
975 buffer_size the size of the buffer
977 Returns: the fixed RFC822 phrase
981 parse_fix_phrase(uschar *phrase, int len, uschar *buffer, int buffer_size)
985 uschar *s, *t, *end, *yield;
987 while (len > 0 && isspace(*phrase)) { phrase++; len--; }
988 if (len > buffer_size/4) return US"Name too long";
990 /* See if there are any non-printing characters, and if so, use the RFC 2047
991 encoding for the whole thing. */
993 for (i = 0, s = phrase; i < len; i++, s++)
994 if ((*s < 32 && *s != '\t') || *s > 126) break;
996 if (i < len) return parse_quote_2047(phrase, len, headers_charset, buffer,
999 /* No non-printers; use the RFC 822 quoting rules */
1003 yield = t = buffer + 1;
1009 /* Copy over quoted strings, remembering we encountered one */
1014 while (s < end && (ch = *s++) != '\"')
1017 if (ch == '\\' && s < end) *t++ = *s++;
1020 if (s >= end) break;
1024 /* Copy over comments, noting if they contain freestanding quote
1035 if (ch == '(') level++;
1036 else if (ch == ')') { if (--level <= 0) break; }
1037 else if (ch == '\\' && s < end) *t++ = *s++ & 127;
1038 else if (ch == '\"') quoted = TRUE;
1042 while (level--) *t++ = ')';
1047 /* Handle special characters that need to be quoted */
1049 else if (Ustrchr(")<>@,;:\\.[]", ch) != NULL)
1051 /* If hit previous quotes just make one quoted "word" */
1056 while (*(--tt) != ' ' && *tt != '\"' && *tt != ')') tt[1] = *tt;
1062 if (ch == ' ' || ch == '\"') { s--; break; } else *t++ = ch;
1067 /* Else quote the whole string so far, and the rest up to any following
1068 quotes. We must treat anything following a backslash as a literal. */
1072 BOOL escaped = (ch == '\\');
1076 /* Now look for the end or a quote */
1082 /* Handle escaped pairs */
1090 else if (ch == '\\')
1096 /* If hit subsequent quotes, insert our quote before any trailing
1097 spaces and back up to re-handle the quote in the outer loop. */
1099 else if (ch == '\"')
1102 while (t[-1] == ' ') { t--; count++; }
1104 while (count-- > 0) *t++ = ' ';
1109 /* If hit a subsequent comment, check it for unescaped quotes,
1110 and if so, end our quote before it. */
1114 uschar *ss = s; /* uschar after '(' */
1119 if (ch == '(') level++;
1120 else if (ch == ')') { if (--level <= 0) break; }
1121 else if (ch == '\\' && ss+1 < end) ss++;
1122 else if (ch == '\"') { quoted = TRUE; break; }
1125 /* Comment contains unescaped quotes; end our quote before
1126 the start of the comment. */
1131 while (t[-1] == ' ') { t--; count++; }
1133 while (count-- > 0) *t++ = ' ';
1137 /* Comment does not contain unescaped quotes; include it in
1142 if (ss >= end) ss--;
1144 Ustrncpy(t, s, ss-s);
1150 /* Not a comment or quote; include this character in our quotes. */
1156 /* Add a final quote if we hit the end of the string. */
1158 if (s >= end) *t++ = '\"';
1161 /* Non-special character; just copy it over */
1171 /*************************************************
1172 * Extract addresses from a list *
1173 *************************************************/
1175 /* This function is called by the redirect router to scan a string containing a
1176 list of addresses separated by commas (with optional white space) or by
1177 newlines, and to generate a chain of address items from them. In other words,
1178 to unpick data from an alias or .forward file.
1180 The SunOS5 documentation for alias files is not very clear on the syntax; it
1181 does not say that either a comma or a newline can be used for separation.
1182 However, that is the way Smail does it, so we follow suit.
1184 If a # character is encountered in a white space position, then characters from
1185 there to the next newline are skipped.
1187 If an unqualified address begins with '\', just skip that character. This gives
1188 compatibility with Sendmail's use of \ to prevent looping. Exim has its own
1189 loop prevention scheme which handles other cases too - see the code in
1192 An "address" can be a specification of a file or a pipe; the latter may often
1193 need to be quoted because it may contain spaces, but we don't want to retain
1194 the quotes. Quotes may appear in normal addresses too, and should be retained.
1195 We can distinguish between these cases, because in addresses, quotes are used
1196 only for parts of the address, not the whole thing. Therefore, we remove quotes
1197 from items when they entirely enclose them, but not otherwise.
1199 An "address" can also be of the form :include:pathname to include a list of
1200 addresses contained in the specified file.
1202 Any unqualified addresses are qualified with and rewritten if necessary, via
1203 the rewrite_address() function.
1206 s the list of addresses (typically a complete
1207 .forward file or a list of entries in an alias file)
1208 options option bits for permitting or denying various special cases;
1209 not all bits are relevant here - some are for filter
1210 files; those we use here are:
1217 anchor where to hang the chain of newly-created addresses. This
1218 should be initialized to NULL.
1219 error where to return an error text
1220 incoming domain domain of the incoming address; used to qualify unqualified
1221 local parts preceded by \
1222 directory if NULL, no checks are done on :include: files
1223 otherwise, included file names must start with the given
1225 syntax_errors if not NULL, it carries on after syntax errors in addresses,
1226 building up a list of errors as error blocks chained on
1229 Returns: FF_DELIVERED addresses extracted
1230 FF_NOTDELIVERED no addresses extracted, but no errors
1231 FF_BLACKHOLE :blackhole:
1234 FF_INCLUDEFAIL some problem with :include:; *error set
1235 FF_ERROR other problems; *error is set
1239 parse_forward_list(uschar *s, int options, address_item **anchor,
1240 uschar **error, uschar *incoming_domain, uschar *directory,
1241 error_block **syntax_errors)
1245 DEBUG(D_route) debug_printf("parse_forward_list: %s\n", s);
1255 BOOL inquote = FALSE;
1259 while (isspace(*s) || *s == ',') s++;
1260 if (*s == '#') { while (*s != 0 && *s != '\n') s++; } else break;
1263 /* When we reach the end of the list, we return FF_DELIVERED if any child
1264 addresses have been generated. If nothing has been generated, there are two
1265 possibilities: either the list is really empty, or there were syntax errors
1266 that are being skipped. (If syntax errors are not being skipped, an FF_ERROR
1267 return is generated on hitting a syntax error and we don't get here.) For a
1268 truly empty list we return FF_NOTDELIVERED so that the router can decline.
1269 However, if the list is empty only because syntax errors were skipped, we
1270 return FF_DELIVERED. */
1274 return (count > 0 || (syntax_errors != NULL && *syntax_errors != NULL))?
1275 FF_DELIVERED : FF_NOTDELIVERED;
1277 /* This previous code returns FF_ERROR if nothing is generated but a
1278 syntax error has been skipped. I now think it is the wrong approach, but
1279 have left this here just in case, and for the record. */
1282 if (count > 0) return FF_DELIVERED; /* Something was generated */
1284 if (syntax_errors == NULL || /* Not skipping syntax errors, or */
1285 *syntax_errors == NULL) /* we didn't actually skip any */
1286 return FF_NOTDELIVERED;
1288 *error = string_sprintf("no addresses generated: syntax error in %s: %s",
1289 (*syntax_errors)->text2, (*syntax_errors)->text1);
1295 /* Find the end of the next address. Quoted strings in addresses may contain
1296 escaped characters; I haven't found a proper specification of .forward or
1297 alias files that mentions the quoting properties, but it seems right to do
1298 the escaping thing in all cases, so use the function that finds the end of an
1299 address. However, don't let a quoted string extend over the end of a line. */
1301 ss = parse_find_address_end(s, TRUE);
1303 /* Remember where we finished, for starting the next one. */
1307 /* Remove any trailing spaces; we know there's at least one non-space. */
1309 while (isspace((ss[-1]))) ss--;
1311 /* We now have s->start and ss->end of the next address. Remove quotes
1312 if they completely enclose, remembering the address started with a quote
1313 for handling pipes and files. Another round of removal of leading and
1314 trailing spaces is then required. */
1316 if (*s == '\"' && ss[-1] == '\"')
1321 while (s < ss && isspace(*s)) s++;
1322 while (ss > s && isspace((ss[-1]))) ss--;
1325 /* Set up the length of the address. */
1333 debug_printf("extract item: %s\n", s);
1337 /* Handle special addresses if permitted. If the address is :unknown:
1338 ignore it - this is for backward compatibility with old alias files. You
1339 don't need to use it nowadays - just generate an empty string. For :defer:,
1340 :blackhole:, or :fail: we have to set up the error message and give up right
1343 if (Ustrncmp(s, ":unknown:", len) == 0)
1349 if (Ustrncmp(s, ":defer:", 7) == 0)
1350 { special = FF_DEFER; specopt = RDO_DEFER; } /* specbit is 0 */
1351 else if (Ustrncmp(s, ":blackhole:", 11) == 0)
1352 { special = FF_BLACKHOLE; specopt = specbit = RDO_BLACKHOLE; }
1353 else if (Ustrncmp(s, ":fail:", 6) == 0)
1354 { special = FF_FAIL; specopt = RDO_FAIL; } /* specbit is 0 */
1358 uschar *ss = Ustrchr(s+1, ':') + 1;
1359 if ((options & specopt) == specbit)
1361 *error = string_sprintf("\"%.*s\" is not permitted", len, s);
1364 while (*ss != 0 && isspace(*ss)) ss++;
1365 while (s[len] != 0 && s[len] != '\n') len++;
1367 *error = string_copy(ss);
1371 /* If the address is of the form :include:pathname, read the file, and call
1372 this function recursively to extract the addresses from it. If directory is
1373 NULL, do no checks. Otherwise, insist that the file name starts with the
1374 given directory and is a regular file. */
1376 if (Ustrncmp(s, ":include:", 9) == 0)
1379 uschar filename[256];
1383 struct stat statbuf;
1387 while (flen > 0 && isspace(*t)) { t++; flen--; }
1391 *error = string_sprintf("file name missing after :include:");
1397 *error = string_sprintf("included file name \"%s\" is too long", t);
1401 Ustrncpy(filename, t, flen);
1404 /* Insist on absolute path */
1406 if (filename[0]!= '/')
1408 *error = string_sprintf("included file \"%s\" is not an absolute path",
1413 /* Check if include is permitted */
1415 if ((options & RDO_INCLUDE) != 0)
1417 *error = US"included files not permitted";
1421 /* Check file name if required */
1423 if (directory != NULL)
1425 int len = Ustrlen(directory);
1426 uschar *p = filename + len;
1428 if (Ustrncmp(filename, directory, len) != 0 || *p != '/')
1430 *error = string_sprintf("included file %s is not in directory %s",
1431 filename, directory);
1435 /* It is necessary to check that every component inside the directory
1436 is NOT a symbolic link, in order to keep the file inside the directory.
1437 This is mighty tedious. It is also not totally foolproof in that it
1438 leaves the possibility of a race attack, but I don't know how to do
1444 while (*(++p) != 0 && *p != '/');
1447 if (Ulstat(filename, &statbuf) != 0)
1449 *error = string_sprintf("failed to stat %s (component of included "
1457 if ((statbuf.st_mode & S_IFMT) == S_IFLNK)
1459 *error = string_sprintf("included file %s in the %s directory "
1460 "involves a symbolic link", filename, directory);
1466 /* Open and stat the file */
1468 if ((f = Ufopen(filename, "rb")) == NULL)
1470 *error = string_open_failed(errno, "included file %s", filename);
1471 return FF_INCLUDEFAIL;
1474 if (fstat(fileno(f), &statbuf) != 0)
1476 *error = string_sprintf("failed to stat included file %s: %s",
1477 filename, strerror(errno));
1479 return FF_INCLUDEFAIL;
1482 /* If directory was checked, double check that we opened a regular file */
1484 if (directory != NULL && (statbuf.st_mode & S_IFMT) != S_IFREG)
1486 *error = string_sprintf("included file %s is not a regular file in "
1487 "the %s directory", filename, directory);
1491 /* Get a buffer and read the contents */
1493 if (statbuf.st_size > MAX_INCLUDE_SIZE)
1495 *error = string_sprintf("included file %s is too big (max %d)",
1496 filename, MAX_INCLUDE_SIZE);
1500 filebuf = store_get(statbuf.st_size + 1);
1501 if (fread(filebuf, 1, statbuf.st_size, f) != statbuf.st_size)
1503 *error = string_sprintf("error while reading included file %s: %s",
1504 filename, strerror(errno));
1508 filebuf[statbuf.st_size] = 0;
1512 frc = parse_forward_list(filebuf, options, &addr,
1513 error, incoming_domain, directory, syntax_errors);
1514 if (frc != FF_DELIVERED && frc != FF_NOTDELIVERED) return frc;
1519 while (last->next != NULL) { count++; last = last->next; }
1520 last->next = *anchor;
1526 /* Else (not :include:) ensure address is syntactically correct and fully
1527 qualified if not a pipe or a file, removing a leading \ if present on an
1528 unqualified address. For pipes and files we must handle quoting. It's
1529 not quite clear exactly what to do for partially quoted things, but the
1530 common case of having the whole thing in quotes is straightforward. If this
1531 was the case, inquote will have been set TRUE above and the quotes removed.
1533 There is a possible ambiguity over addresses whose local parts start with
1534 a vertical bar or a slash, and the latter do in fact occur, thanks to X.400.
1535 Consider a .forward file that contains the line
1537 /X=xxx/Y=xxx/OU=xxx/@some.gate.way
1539 Is this a file or an X.400 address? Does it make any difference if it is in
1540 quotes? On the grounds that file names of this type are rare, Exim treats
1541 something that parses as an RFC 822 address and has a domain as an address
1542 rather than a file or a pipe. This is also how an address such as the above
1543 would be treated if it came in from outside. */
1547 int start, end, domain;
1548 uschar *recipient = NULL;
1552 /* If it starts with \ and the rest of it parses as a valid mail address
1553 without a domain, carry on with that address, but qualify it with the
1554 incoming domain. Otherwise arrange for the address to fall through,
1555 causing an error message on the re-parse. */
1560 parse_extract_address(s+1, error, &start, &end, &domain, FALSE);
1561 if (recipient != NULL)
1562 recipient = (domain != 0)? NULL :
1563 string_sprintf("%s@%s", recipient, incoming_domain);
1566 /* Try parsing the item as an address. */
1568 if (recipient == NULL) recipient =
1569 parse_extract_address(s, error, &start, &end, &domain, FALSE);
1571 /* If item starts with / or | and is not a valid address, or there
1572 is no domain, treat it as a file or pipe. If it was a quoted item,
1573 remove the quoting occurrences of \ within it. */
1575 if ((*s == '|' || *s == '/') && (recipient == NULL || domain == 0))
1577 uschar *t = store_get(Ustrlen(s) + 1);
1584 *p++ = (*q == '\\')? *(++q) : *q;
1590 addr = deliver_make_addr(t, TRUE);
1591 setflag(addr, af_pfr); /* indicates pipe/file/reply */
1592 if (*s != '|') setflag(addr, af_file); /* indicates file */
1595 /* Item must be an address. Complain if not, else qualify, rewrite and set
1596 up the control block. It appears that people are in the habit of using
1597 empty addresses but with comments as a way of putting comments into
1598 alias and forward files. Therefore, ignore the error "empty address".
1599 Mailing lists might want to tolerate syntax errors; there is therefore
1600 an option to do so. */
1604 if (recipient == NULL)
1606 if (Ustrcmp(*error, "empty address") == 0)
1614 if (syntax_errors != NULL)
1616 error_block *e = store_get(sizeof(error_block));
1617 error_block *last = *syntax_errors;
1618 if (last == NULL) *syntax_errors = e; else
1620 while (last->next != NULL) last = last->next;
1625 e->text2 = string_copy(s);
1632 *error = string_sprintf("%s in \"%s\"", *error, s);
1633 s[len] = save; /* _after_ using it for *error */
1638 /* Address was successfully parsed. Rewrite, and then make an address
1641 recipient = ((options & RDO_REWRITE) != 0)?
1642 rewrite_address(recipient, TRUE, FALSE, global_rewrite_rules,
1643 rewrite_existflags) :
1644 rewrite_address_qualify(recipient, TRUE);
1645 addr = deliver_make_addr(recipient, TRUE); /* TRUE => copy recipient */
1648 /* Restore the final character in the original data, and add to the
1652 addr->next = *anchor;
1657 /* Advance pointer for the next address */
1664 /*************************************************
1665 **************************************************
1666 * Stand-alone test program *
1667 **************************************************
1668 *************************************************/
1670 #if defined STAND_ALONE
1673 int start, end, domain;
1674 uschar buffer[1024];
1675 uschar outbuff[1024];
1677 big_buffer = store_malloc(big_buffer_size);
1679 /* strip_trailing_dot = TRUE; */
1680 allow_domain_literals = TRUE;
1682 printf("Testing parse_fix_phrase\n");
1684 while (Ufgets(buffer, sizeof(buffer), stdin) != NULL)
1686 buffer[Ustrlen(buffer)-1] = 0;
1687 if (buffer[0] == 0) break;
1688 printf("%s\n", CS parse_fix_phrase(buffer, Ustrlen(buffer), outbuff,
1692 printf("Testing parse_extract_address without group syntax and without UTF-8\n");
1694 while (Ufgets(buffer, sizeof(buffer), stdin) != NULL)
1698 buffer[Ustrlen(buffer) - 1] = 0;
1699 if (buffer[0] == 0) break;
1700 out = parse_extract_address(buffer, &errmess, &start, &end, &domain, FALSE);
1701 if (out == NULL) printf("*** bad address: %s\n", errmess); else
1703 uschar extract[1024];
1704 Ustrncpy(extract, buffer+start, end-start);
1705 extract[end-start] = 0;
1706 printf("%s %d %d %d \"%s\"\n", out, start, end, domain, extract);
1710 printf("Testing parse_extract_address without group syntax but with UTF-8\n");
1712 allow_utf8_domains = TRUE;
1713 while (Ufgets(buffer, sizeof(buffer), stdin) != NULL)
1717 buffer[Ustrlen(buffer) - 1] = 0;
1718 if (buffer[0] == 0) break;
1719 out = parse_extract_address(buffer, &errmess, &start, &end, &domain, FALSE);
1720 if (out == NULL) printf("*** bad address: %s\n", errmess); else
1722 uschar extract[1024];
1723 Ustrncpy(extract, buffer+start, end-start);
1724 extract[end-start] = 0;
1725 printf("%s %d %d %d \"%s\"\n", out, start, end, domain, extract);
1728 allow_utf8_domains = FALSE;
1730 printf("Testing parse_extract_address with group syntax\n");
1732 parse_allow_group = TRUE;
1733 while (Ufgets(buffer, sizeof(buffer), stdin) != NULL)
1738 buffer[Ustrlen(buffer) - 1] = 0;
1739 if (buffer[0] == 0) break;
1743 uschar *ss = parse_find_address_end(s, FALSE);
1744 int terminator = *ss;
1746 out = parse_extract_address(buffer, &errmess, &start, &end, &domain, FALSE);
1749 if (out == NULL) printf("*** bad address: %s\n", errmess); else
1751 uschar extract[1024];
1752 Ustrncpy(extract, buffer+start, end-start);
1753 extract[end-start] = 0;
1754 printf("%s %d %d %d \"%s\"\n", out, start, end, domain, extract);
1757 s = ss + (terminator? 1:0);
1758 while (isspace(*s)) s++;
1762 printf("Testing parse_find_at\n");
1764 while (Ufgets(buffer, sizeof(buffer), stdin) != NULL)
1767 buffer[Ustrlen(buffer)-1] = 0;
1768 if (buffer[0] == 0) break;
1769 s = parse_find_at(buffer);
1770 if (s == NULL) printf("no @ found\n");
1771 else printf("offset = %d\n", s - buffer);
1774 printf("Testing parse_extract_addresses\n");
1776 while (Ufgets(buffer, sizeof(buffer), stdin) != NULL)
1780 address_item *anchor = NULL;
1781 buffer[Ustrlen(buffer) - 1] = 0;
1782 if (buffer[0] == 0) break;
1783 if ((extracted = parse_forward_list(buffer, -1, &anchor,
1784 &errmess, US"incoming.domain", NULL, NULL)) == FF_DELIVERED)
1786 while (anchor != NULL)
1788 address_item *addr = anchor;
1789 anchor = anchor->next;
1790 printf("%d %s\n", testflag(addr, af_pfr), addr->address);
1793 else printf("Failed: %d %s\n", extracted, errmess);
1801 /* End of parse.c */