1 /* $Cambridge: exim/src/src/regex.c,v 1.7 2005/07/01 10:49:02 ph10 Exp $ */
3 /*************************************************
4 * Exim - an Internet mail transport agent *
5 *************************************************/
7 /* Copyright (c) Tom Kistner <tom@duncanthrax.net> 2003-???? */
10 /* Code for matching regular expressions against headers and body.
14 #ifdef WITH_CONTENT_SCAN
18 /* Structure to hold a list of Regular expressions */
19 typedef struct pcre_list
{
22 struct pcre_list
*next
;
25 uschar regex_match_string_buffer
[1024];
27 extern FILE *mime_stream
;
28 extern uschar
*mime_current_boundary
;
30 int regex(uschar
**listptr
) {
32 uschar
*list
= *listptr
;
34 uschar regex_string_buffer
[1024];
35 unsigned long mbox_size
;
38 pcre_list
*re_list_head
= NULL
;
39 pcre_list
*re_list_item
;
40 const char *pcre_error
;
45 /* reset expansion variable */
46 regex_match_string
= NULL
;
48 if (mime_stream
== NULL
) {
49 /* We are in the DATA ACL */
50 mbox_file
= spool_mbox(&mbox_size
);
51 if (mbox_file
== NULL
) {
52 /* error while spooling */
53 log_write(0, LOG_MAIN
|LOG_PANIC
,
54 "regex acl condition: error while creating mbox spool file");
59 f_pos
= ftell(mime_stream
);
60 mbox_file
= mime_stream
;
63 /* precompile our regexes */
64 while ((regex_string
= string_nextinlist(&list
, &sep
,
66 sizeof(regex_string_buffer
))) != NULL
) {
69 if ( (strcmpic(regex_string
,US
"false") == 0) ||
70 (Ustrcmp(regex_string
,"0") == 0) ) {
71 /* explicitly no matching */
75 /* compile our regular expression */
76 re
= pcre_compile( CS regex_string
,
83 log_write(0, LOG_MAIN
,
84 "regex acl condition warning - error in regex '%s': %s at offset %d, skipped.", regex_string
, pcre_error
, pcre_erroffset
);
88 re_list_item
= store_get(sizeof(pcre_list
));
89 re_list_item
->re
= re
;
90 re_list_item
->pcre_text
= string_copy(regex_string
);
91 re_list_item
->next
= re_list_head
;
92 re_list_head
= re_list_item
;
96 /* no regexes -> nothing to do */
97 if (re_list_head
== NULL
) {
101 /* match each line against all regexes */
102 linebuffer
= store_get(32767);
103 while (fgets(CS linebuffer
, 32767, mbox_file
) != NULL
) {
104 if ( (mime_stream
!= NULL
) && (mime_current_boundary
!= NULL
) ) {
106 if (Ustrncmp(linebuffer
,"--",2) == 0) {
107 if (Ustrncmp((linebuffer
+2),mime_current_boundary
,Ustrlen(mime_current_boundary
)) == 0)
112 re_list_item
= re_list_head
;
114 /* try matcher on the line */
115 if (pcre_exec(re_list_item
->re
, NULL
, CS linebuffer
,
116 (int)Ustrlen(linebuffer
), 0, 0, NULL
, 0) >= 0) {
117 Ustrncpy(regex_match_string_buffer
, re_list_item
->pcre_text
, 1023);
118 regex_match_string
= regex_match_string_buffer
;
119 if (mime_stream
== NULL
)
120 (void)fclose(mbox_file
);
122 clearerr(mime_stream
);
123 fseek(mime_stream
,f_pos
,SEEK_SET
);
127 re_list_item
= re_list_item
->next
;
128 } while (re_list_item
!= NULL
);
131 if (mime_stream
== NULL
)
132 (void)fclose(mbox_file
);
134 clearerr(mime_stream
);
135 fseek(mime_stream
,f_pos
,SEEK_SET
);
143 int mime_regex(uschar
**listptr
) {
145 uschar
*list
= *listptr
;
146 uschar
*regex_string
;
147 uschar regex_string_buffer
[1024];
149 pcre_list
*re_list_head
= NULL
;
150 pcre_list
*re_list_item
;
151 const char *pcre_error
;
154 uschar
*mime_subject
= NULL
;
155 int mime_subject_len
= 0;
157 /* reset expansion variable */
158 regex_match_string
= NULL
;
160 /* precompile our regexes */
161 while ((regex_string
= string_nextinlist(&list
, &sep
,
163 sizeof(regex_string_buffer
))) != NULL
) {
166 if ( (strcmpic(regex_string
,US
"false") == 0) ||
167 (Ustrcmp(regex_string
,"0") == 0) ) {
168 /* explicitly no matching */
172 /* compile our regular expression */
173 re
= pcre_compile( CS regex_string
,
180 log_write(0, LOG_MAIN
,
181 "regex acl condition warning - error in regex '%s': %s at offset %d, skipped.", regex_string
, pcre_error
, pcre_erroffset
);
185 re_list_item
= store_get(sizeof(pcre_list
));
186 re_list_item
->re
= re
;
187 re_list_item
->pcre_text
= string_copy(regex_string
);
188 re_list_item
->next
= re_list_head
;
189 re_list_head
= re_list_item
;
193 /* no regexes -> nothing to do */
194 if (re_list_head
== NULL
) {
198 /* check if the file is already decoded */
199 if (mime_decoded_filename
== NULL
) {
200 uschar
*empty
= US
"";
201 /* no, decode it first */
203 if (mime_decoded_filename
== NULL
) {
204 /* decoding failed */
205 log_write(0, LOG_MAIN
,
206 "mime_regex acl condition warning - could not decode MIME part to file.");
213 f
= fopen(CS mime_decoded_filename
, "rb");
216 log_write(0, LOG_MAIN
,
217 "mime_regex acl condition warning - can't open '%s' for reading.", mime_decoded_filename
);
222 mime_subject
= (uschar
*)store_get(32767);
224 /* read max 32k chars from file */
225 mime_subject_len
= fread(mime_subject
, 1, 32766, f
);
227 re_list_item
= re_list_head
;
229 /* try matcher on the mmapped file */
230 debug_printf("Matching '%s'\n", re_list_item
->pcre_text
);
231 if (pcre_exec(re_list_item
->re
, NULL
, CS mime_subject
,
232 mime_subject_len
, 0, 0, NULL
, 0) >= 0) {
233 Ustrncpy(regex_match_string_buffer
, re_list_item
->pcre_text
, 1023);
234 regex_match_string
= regex_match_string_buffer
;
238 re_list_item
= re_list_item
->next
;
239 } while (re_list_item
!= NULL
);