2 * PDKIM - a RFC4871 (DKIM) implementation
4 * Copyright (C) 2009 Tom Kistner <tom@duncanthrax.net>
6 * http://duncanthrax.net/pdkim/
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License along
19 * with this program; if not, write to the Free Software Foundation, Inc.,
20 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
35 #define PDKIM_SIGNATURE_VERSION "1"
36 #define PDKIM_PUB_RECORD_VERSION "DKIM1"
38 #define PDKIM_MAX_HEADER_LEN 65536
39 #define PDKIM_MAX_HEADERS 512
40 #define PDKIM_MAX_BODY_LINE_LEN 16384
41 #define PDKIM_DNS_TXT_MAX_NAMELEN 1024
42 #define PDKIM_DEFAULT_SIGN_HEADERS "From:Sender:Reply-To:Subject:Date:"\
43 "Message-ID:To:Cc:MIME-Version:Content-Type:"\
44 "Content-Transfer-Encoding:Content-ID:"\
45 "Content-Description:Resent-Date:Resent-From:"\
46 "Resent-Sender:Resent-To:Resent-Cc:"\
47 "Resent-Message-ID:In-Reply-To:References:"\
48 "List-Id:List-Help:List-Unsubscribe:"\
49 "List-Subscribe:List-Post:List-Owner:List-Archive"
51 /* -------------------------------------------------------------------------- */
52 struct pdkim_stringlist
{
57 #define PDKIM_STR_ALLOC_FRAG 256
61 unsigned int allocated
;
64 /* -------------------------------------------------------------------------- */
65 /* A bunch of list constants */
66 const char *pdkim_querymethods
[] = {
70 const char *pdkim_algos
[] = {
75 const char *pdkim_canons
[] = {
80 const char *pdkim_hashes
[] = {
85 const char *pdkim_keytypes
[] = {
90 typedef struct pdkim_combined_canon_entry
{
94 } pdkim_combined_canon_entry
;
95 pdkim_combined_canon_entry pdkim_combined_canons
[] = {
96 { "simple/simple", PDKIM_CANON_SIMPLE
, PDKIM_CANON_SIMPLE
},
97 { "simple/relaxed", PDKIM_CANON_SIMPLE
, PDKIM_CANON_RELAXED
},
98 { "relaxed/simple", PDKIM_CANON_RELAXED
, PDKIM_CANON_SIMPLE
},
99 { "relaxed/relaxed", PDKIM_CANON_RELAXED
, PDKIM_CANON_RELAXED
},
100 { "simple", PDKIM_CANON_SIMPLE
, PDKIM_CANON_SIMPLE
},
101 { "relaxed", PDKIM_CANON_RELAXED
, PDKIM_CANON_SIMPLE
},
106 const char *pdkim_verify_status_str(int status
) {
108 case PDKIM_VERIFY_NONE
: return "PDKIM_VERIFY_NONE";
109 case PDKIM_VERIFY_INVALID
: return "PDKIM_VERIFY_INVALID";
110 case PDKIM_VERIFY_FAIL
: return "PDKIM_VERIFY_FAIL";
111 case PDKIM_VERIFY_PASS
: return "PDKIM_VERIFY_PASS";
112 default: return "PDKIM_VERIFY_UNKNOWN";
115 const char *pdkim_verify_ext_status_str(int ext_status
) {
117 case PDKIM_VERIFY_FAIL_BODY
: return "PDKIM_VERIFY_FAIL_BODY";
118 case PDKIM_VERIFY_FAIL_MESSAGE
: return "PDKIM_VERIFY_FAIL_MESSAGE";
119 case PDKIM_VERIFY_INVALID_PUBKEY_UNAVAILABLE
: return "PDKIM_VERIFY_INVALID_PUBKEY_UNAVAILABLE";
120 case PDKIM_VERIFY_INVALID_BUFFER_SIZE
: return "PDKIM_VERIFY_INVALID_BUFFER_SIZE";
121 case PDKIM_VERIFY_INVALID_PUBKEY_PARSING
: return "PDKIM_VERIFY_INVALID_PUBKEY_PARSING";
122 default: return "PDKIM_VERIFY_UNKNOWN";
127 /* -------------------------------------------------------------------------- */
128 /* Print debugging functions */
130 void pdkim_quoteprint(FILE *stream
, const char *data
, int len
, int lf
) {
132 const unsigned char *p
= (const unsigned char *)data
;
134 for (i
=0;i
<len
;i
++) {
137 case ' ' : fprintf(stream
,"{SP}"); break;
138 case '\t': fprintf(stream
,"{TB}"); break;
139 case '\r': fprintf(stream
,"{CR}"); break;
140 case '\n': fprintf(stream
,"{LF}"); break;
141 case '{' : fprintf(stream
,"{BO}"); break;
142 case '}' : fprintf(stream
,"{BC}"); break;
144 if ( (c
< 32) || (c
> 127) )
145 fprintf(stream
,"{%02x}",c
);
154 void pdkim_hexprint(FILE *stream
, const char *data
, int len
, int lf
) {
156 const unsigned char *p
= (const unsigned char *)data
;
158 for (i
=0;i
<len
;i
++) {
160 fprintf(stream
,"%02x",c
);
168 /* -------------------------------------------------------------------------- */
169 /* Simple string list implementation for convinience */
170 pdkim_stringlist
*pdkim_append_stringlist(pdkim_stringlist
*base
, char *str
) {
171 pdkim_stringlist
*new_entry
= malloc(sizeof(pdkim_stringlist
));
172 if (new_entry
== NULL
) return NULL
;
173 memset(new_entry
,0,sizeof(pdkim_stringlist
));
174 new_entry
->value
= strdup(str
);
175 if (new_entry
->value
== NULL
) return NULL
;
177 pdkim_stringlist
*last
= base
;
178 while (last
->next
!= NULL
) { last
= last
->next
; }
179 last
->next
= new_entry
;
182 else return new_entry
;
184 pdkim_stringlist
*pdkim_prepend_stringlist(pdkim_stringlist
*base
, char *str
) {
185 pdkim_stringlist
*new_entry
= malloc(sizeof(pdkim_stringlist
));
186 if (new_entry
== NULL
) return NULL
;
187 memset(new_entry
,0,sizeof(pdkim_stringlist
));
188 new_entry
->value
= strdup(str
);
189 if (new_entry
->value
== NULL
) return NULL
;
191 new_entry
->next
= base
;
197 /* -------------------------------------------------------------------------- */
198 /* A small "growing string" implementation to escape malloc/realloc hell */
199 pdkim_str
*pdkim_strnew (const char *cstr
) {
200 unsigned int len
= cstr
?strlen(cstr
):0;
201 pdkim_str
*p
= malloc(sizeof(pdkim_str
));
202 if (p
== NULL
) return NULL
;
203 memset(p
,0,sizeof(pdkim_str
));
204 p
->str
= malloc(len
+1);
205 if (p
->str
== NULL
) {
209 p
->allocated
=(len
+1);
211 if (cstr
) strcpy(p
->str
,cstr
);
212 else p
->str
[p
->len
] = '\0';
215 char *pdkim_strncat(pdkim_str
*str
, const char *data
, int len
) {
216 if ((str
->allocated
- str
->len
) < (len
+1)) {
217 /* Extend the buffer */
218 int num_frags
= ((len
+1)/PDKIM_STR_ALLOC_FRAG
)+1;
219 char *n
= realloc(str
->str
,
220 (str
->allocated
+(num_frags
*PDKIM_STR_ALLOC_FRAG
)));
221 if (n
== NULL
) return NULL
;
223 str
->allocated
+= (num_frags
*PDKIM_STR_ALLOC_FRAG
);
225 strncpy(&(str
->str
[str
->len
]),data
,len
);
227 str
->str
[str
->len
] = '\0';
230 char *pdkim_strcat(pdkim_str
*str
, const char *cstr
) {
231 return pdkim_strncat(str
, cstr
, strlen(cstr
));
233 char *pdkim_numcat(pdkim_str
*str
, unsigned long num
) {
235 snprintf(minibuf
,20,"%lu",num
);
236 return pdkim_strcat(str
,minibuf
);
238 char *pdkim_strtrim(pdkim_str
*str
) {
241 while ( (*p
!= '\0') && ((*p
== '\t') || (*p
== ' ')) ) p
++;
242 while (*p
!= '\0') {*q
= *p
; q
++; p
++;}
244 while ( (q
!= str
->str
) && ( (*q
== '\0') || (*q
== '\t') || (*q
== ' ') ) ) {
248 str
->len
= strlen(str
->str
);
251 char *pdkim_strclear(pdkim_str
*str
) {
256 void pdkim_strfree(pdkim_str
*str
) {
257 if (str
== NULL
) return;
258 if (str
->str
!= NULL
) free(str
->str
);
264 /* -------------------------------------------------------------------------- */
265 void pdkim_free_pubkey(pdkim_pubkey
*pub
) {
267 if (pub
->version
!= NULL
) free(pub
->version
);
268 if (pub
->granularity
!= NULL
) free(pub
->granularity
);
269 if (pub
->hashes
!= NULL
) free(pub
->hashes
);
270 if (pub
->keytype
!= NULL
) free(pub
->keytype
);
271 if (pub
->srvtype
!= NULL
) free(pub
->srvtype
);
272 if (pub
->notes
!= NULL
) free(pub
->notes
);
273 if (pub
->key
!= NULL
) free(pub
->key
);
279 /* -------------------------------------------------------------------------- */
280 void pdkim_free_sig(pdkim_signature
*sig
) {
282 pdkim_signature
*next
= (pdkim_signature
*)sig
->next
;
284 pdkim_stringlist
*e
= sig
->headers
;
286 pdkim_stringlist
*c
= e
;
287 if (e
->value
!= NULL
) free(e
->value
);
292 if (sig
->sigdata
!= NULL
) free(sig
->sigdata
);
293 if (sig
->bodyhash
!= NULL
) free(sig
->bodyhash
);
294 if (sig
->selector
!= NULL
) free(sig
->selector
);
295 if (sig
->domain
!= NULL
) free(sig
->domain
);
296 if (sig
->identity
!= NULL
) free(sig
->identity
);
297 if (sig
->headernames
!= NULL
) free(sig
->headernames
);
298 if (sig
->copiedheaders
!= NULL
) free(sig
->copiedheaders
);
299 if (sig
->rsa_privkey
!= NULL
) free(sig
->rsa_privkey
);
300 if (sig
->sign_headers
!= NULL
) free(sig
->sign_headers
);
301 if (sig
->signature_header
!= NULL
) free(sig
->signature_header
);
302 if (sig
->sha1_body
!= NULL
) free(sig
->sha1_body
);
303 if (sig
->sha2_body
!= NULL
) free(sig
->sha2_body
);
304 if (sig
->hnames_check
!= NULL
) free(sig
->hnames_check
);
306 if (sig
->pubkey
!= NULL
) pdkim_free_pubkey(sig
->pubkey
);
309 if (next
!= NULL
) pdkim_free_sig(next
);
314 /* -------------------------------------------------------------------------- */
315 DLLEXPORT
void pdkim_free_ctx(pdkim_ctx
*ctx
) {
317 pdkim_free_sig(ctx
->sig
);
318 pdkim_strfree(ctx
->cur_header
);
324 /* -------------------------------------------------------------------------- */
325 /* Matches the name of the passed raw "header" against
326 the passed colon-separated "list", starting at entry
327 "start". Returns the position of the header name in
329 int header_name_match(const char *header
,
338 /* Get header name */
339 char *hcolon
= strchr(header
,':');
340 if (hcolon
== NULL
) return rc
; /* This isn't a header */
341 hname
= malloc((hcolon
-header
)+1);
342 if (hname
== NULL
) return PDKIM_ERR_OOM
;
343 memset(hname
,0,(hcolon
-header
)+1);
344 strncpy(hname
,header
,(hcolon
-header
));
346 /* Copy tick-off list locally, so we can punch zeroes into it */
347 lcopy
= strdup(tick
);
350 return PDKIM_ERR_OOM
;
357 if (strcasecmp(p
,hname
) == 0) {
359 /* Invalidate header name instance in tick-off list */
360 if (do_tick
) tick
[p
-lcopy
] = '_';
368 if (strcasecmp(p
,hname
) == 0) {
370 /* Invalidate header name instance in tick-off list */
371 if (do_tick
) tick
[p
-lcopy
] = '_';
381 /* -------------------------------------------------------------------------- */
382 /* Performs "relaxed" canonicalization of a header. The returned pointer needs
384 char *pdkim_relax_header (char *header
, int crlf
) {
385 int past_field_name
= 0;
389 char *relaxed
= malloc(strlen(header
)+3);
390 if (relaxed
== NULL
) return NULL
;
395 if ( (c
== '\r') || (c
== '\n') ) {
399 if ( (c
== '\t') || (c
== ' ') ) {
400 c
= ' '; /* Turns WSP into SP */
408 if ( (!past_field_name
) && (c
== ':') ) {
409 if (seen_wsp
) q
--; /* This removes WSP before the colon */
410 seen_wsp
= 1; /* This removes WSP after the colon */
415 /* Lowercase header name */
416 if (!past_field_name
) c
= tolower(c
);
421 if ((q
>relaxed
) && (*(q
-1) == ' ')) q
--; /* Squash eventual trailing SP */
423 if (crlf
) strcat(relaxed
,"\r\n");
428 /* -------------------------------------------------------------------------- */
429 #define PDKIM_QP_ERROR_DECODE -1
430 char *pdkim_decode_qp_char(char *qp_p
, int *c
) {
431 char *initial_pos
= qp_p
;
433 /* Advance one char */
436 /* Check for two hex digits and decode them */
437 if (isxdigit(*qp_p
) && isxdigit(qp_p
[1])) {
438 /* Do hex conversion */
439 if (isdigit(*qp_p
)) {*c
= *qp_p
- '0';}
440 else {*c
= toupper(*qp_p
) - 'A' + 10;}
442 if (isdigit(qp_p
[1])) {*c
|= qp_p
[1] - '0';}
443 else {*c
|= toupper(qp_p
[1]) - 'A' + 10;}
447 /* Illegal char here */
448 *c
= PDKIM_QP_ERROR_DECODE
;
453 /* -------------------------------------------------------------------------- */
454 char *pdkim_decode_qp(char *str
) {
458 char *n
= malloc(strlen(p
)+1);
459 if (n
== NULL
) return NULL
;
464 p
= pdkim_decode_qp_char(p
,&nchar
);
482 /* -------------------------------------------------------------------------- */
483 char *pdkim_decode_base64(char *str
, int *num_decoded
) {
487 base64_decode(NULL
, &dlen
, (unsigned char *)str
, strlen(str
));
488 res
= malloc(dlen
+1);
489 if (res
== NULL
) return NULL
;
490 if (base64_decode((unsigned char *)res
,&dlen
,(unsigned char *)str
,strlen(str
)) != 0) {
494 if (num_decoded
!= NULL
) *num_decoded
= dlen
;
498 /* -------------------------------------------------------------------------- */
499 char *pdkim_encode_base64(char *str
, int num
) {
503 base64_encode(NULL
, &dlen
, (unsigned char *)str
, num
);
504 res
= malloc(dlen
+1);
505 if (res
== NULL
) return NULL
;
506 if (base64_encode((unsigned char *)res
,&dlen
,(unsigned char *)str
,num
) != 0) {
514 /* -------------------------------------------------------------------------- */
515 #define PDKIM_HDR_LIMBO 0
516 #define PDKIM_HDR_TAG 1
517 #define PDKIM_HDR_VALUE 2
518 pdkim_signature
*pdkim_parse_sig_header(pdkim_ctx
*ctx
, char *raw_hdr
) {
519 pdkim_signature
*sig
;
521 pdkim_str
*cur_tag
= NULL
;
522 pdkim_str
*cur_val
= NULL
;
525 int where
= PDKIM_HDR_LIMBO
;
528 sig
= malloc(sizeof(pdkim_signature
));
529 if (sig
== NULL
) return NULL
;
530 memset(sig
,0,sizeof(pdkim_signature
));
531 sig
->bodylength
= -1;
533 sig
->rawsig_no_b_val
= malloc(strlen(raw_hdr
)+1);
534 if (sig
->rawsig_no_b_val
== NULL
) {
540 q
= sig
->rawsig_no_b_val
;
545 if ( (*p
== '\r') || (*p
== '\n') )
548 /* Fast-forward through header name */
550 if (*p
== ':') past_hname
= 1;
554 if (where
== PDKIM_HDR_LIMBO
) {
555 /* In limbo, just wait for a tag-char to appear */
556 if (!((*p
>= 'a') && (*p
<= 'z')))
559 where
= PDKIM_HDR_TAG
;
562 if (where
== PDKIM_HDR_TAG
) {
564 cur_tag
= pdkim_strnew(NULL
);
566 if ((*p
>= 'a') && (*p
<= 'z'))
567 pdkim_strncat(cur_tag
,p
,1);
570 if (strcmp(cur_tag
->str
,"b") == 0) {
574 where
= PDKIM_HDR_VALUE
;
579 if (where
== PDKIM_HDR_VALUE
) {
581 cur_val
= pdkim_strnew(NULL
);
583 if ( (*p
== '\r') || (*p
== '\n') || (*p
== ' ') || (*p
== '\t') )
586 if ( (*p
== ';') || (*p
== '\0') ) {
587 if (cur_tag
->len
> 0) {
588 pdkim_strtrim(cur_val
);
590 if (ctx
->debug_stream
)
591 fprintf(ctx
->debug_stream
, "%s=%s\n", cur_tag
->str
, cur_val
->str
);
593 switch (cur_tag
->str
[0]) {
595 switch (cur_tag
->str
[1]) {
597 sig
->bodyhash
= pdkim_decode_base64(cur_val
->str
,&(sig
->bodyhash_len
));
600 sig
->sigdata
= pdkim_decode_base64(cur_val
->str
,&(sig
->sigdata_len
));
605 if (strcmp(cur_val
->str
,PDKIM_SIGNATURE_VERSION
) == 0) {
606 /* We only support version 1, and that is currently the
607 only version there is. */
613 while (pdkim_algos
[i
] != NULL
) {
614 if (strcmp(cur_val
->str
,pdkim_algos
[i
]) == 0 ) {
623 while (pdkim_combined_canons
[i
].str
!= NULL
) {
624 if (strcmp(cur_val
->str
,pdkim_combined_canons
[i
].str
) == 0 ) {
625 sig
->canon_headers
= pdkim_combined_canons
[i
].canon_headers
;
626 sig
->canon_body
= pdkim_combined_canons
[i
].canon_body
;
634 while (pdkim_querymethods
[i
] != NULL
) {
635 if (strcmp(cur_val
->str
,pdkim_querymethods
[i
]) == 0 ) {
636 sig
->querymethod
= i
;
643 sig
->selector
= strdup(cur_val
->str
);
646 sig
->domain
= strdup(cur_val
->str
);
649 sig
->identity
= pdkim_decode_qp(cur_val
->str
);
652 sig
->created
= strtoul(cur_val
->str
,NULL
,10);
655 sig
->expires
= strtoul(cur_val
->str
,NULL
,10);
658 sig
->bodylength
= strtol(cur_val
->str
,NULL
,10);
661 sig
->headernames
= strdup(cur_val
->str
);
664 sig
->copiedheaders
= pdkim_decode_qp(cur_val
->str
);
668 if (ctx
->debug_stream
)
669 fprintf(ctx
->debug_stream
, "Unknown tag encountered\n");
674 pdkim_strclear(cur_tag
);
675 pdkim_strclear(cur_val
);
677 where
= PDKIM_HDR_LIMBO
;
680 else pdkim_strncat(cur_val
,p
,1);
684 if (*p
== '\0') break;
693 /* Make sure the most important bits are there. */
694 if (!(sig
->domain
&& (*(sig
->domain
) != '\0') &&
695 sig
->selector
&& (*(sig
->selector
) != '\0') &&
696 sig
->headernames
&& (*(sig
->headernames
) != '\0') &&
704 /* Copy header list to 'tick-off' header list */
705 sig
->hnames_check
= strdup(sig
->headernames
);
708 /* Chomp raw header. The final newline must not be added to the signature. */
710 while( (q
> sig
->rawsig_no_b_val
) && ((*q
== '\r') || (*q
== '\n')) ) {
715 if (ctx
->debug_stream
) {
716 fprintf(ctx
->debug_stream
,
717 "PDKIM >> Raw signature w/o b= tag value >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
718 pdkim_quoteprint(ctx
->debug_stream
,
719 sig
->rawsig_no_b_val
,
720 strlen(sig
->rawsig_no_b_val
), 1);
721 fprintf(ctx
->debug_stream
,
722 "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
726 sig
->sha1_body
= malloc(sizeof(sha1_context
));
727 if (sig
->sha1_body
== NULL
) {
731 sig
->sha2_body
= malloc(sizeof(sha2_context
));
732 if (sig
->sha2_body
== NULL
) {
737 sha1_starts(sig
->sha1_body
);
738 sha2_starts(sig
->sha2_body
,0);
744 /* -------------------------------------------------------------------------- */
745 pdkim_pubkey
*pdkim_parse_pubkey_record(pdkim_ctx
*ctx
, char *raw_record
) {
748 pdkim_str
*cur_tag
= NULL
;
749 pdkim_str
*cur_val
= NULL
;
750 int where
= PDKIM_HDR_LIMBO
;
752 pub
= malloc(sizeof(pdkim_pubkey
));
753 if (pub
== NULL
) return NULL
;
754 memset(pub
,0,sizeof(pdkim_pubkey
));
761 if ( (*p
== '\r') || (*p
== '\n') )
764 if (where
== PDKIM_HDR_LIMBO
) {
765 /* In limbo, just wait for a tag-char to appear */
766 if (!((*p
>= 'a') && (*p
<= 'z')))
769 where
= PDKIM_HDR_TAG
;
772 if (where
== PDKIM_HDR_TAG
) {
774 cur_tag
= pdkim_strnew(NULL
);
776 if ((*p
>= 'a') && (*p
<= 'z'))
777 pdkim_strncat(cur_tag
,p
,1);
780 where
= PDKIM_HDR_VALUE
;
785 if (where
== PDKIM_HDR_VALUE
) {
787 cur_val
= pdkim_strnew(NULL
);
789 if ( (*p
== '\r') || (*p
== '\n') )
792 if ( (*p
== ';') || (*p
== '\0') ) {
793 if (cur_tag
->len
> 0) {
794 pdkim_strtrim(cur_val
);
796 if (ctx
->debug_stream
)
797 fprintf(ctx
->debug_stream
, "%s=%s\n", cur_tag
->str
, cur_val
->str
);
799 switch (cur_tag
->str
[0]) {
801 /* This tag isn't evaluated because:
802 - We only support version DKIM1.
803 - Which is the default for this value (set below)
804 - Other versions are currently not specified. */
807 pub
->hashes
= strdup(cur_val
->str
);
810 pub
->granularity
= strdup(cur_val
->str
);
813 pub
->notes
= pdkim_decode_qp(cur_val
->str
);
816 pub
->key
= pdkim_decode_base64(cur_val
->str
,&(pub
->key_len
));
819 pub
->hashes
= strdup(cur_val
->str
);
822 pub
->srvtype
= strdup(cur_val
->str
);
825 if (strchr(cur_val
->str
,'y') != NULL
) pub
->testing
= 1;
826 if (strchr(cur_val
->str
,'s') != NULL
) pub
->no_subdomaining
= 1;
830 if (ctx
->debug_stream
)
831 fprintf(ctx
->debug_stream
, "Unknown tag encountered\n");
836 pdkim_strclear(cur_tag
);
837 pdkim_strclear(cur_val
);
838 where
= PDKIM_HDR_LIMBO
;
841 else pdkim_strncat(cur_val
,p
,1);
845 if (*p
== '\0') break;
849 /* Set fallback defaults */
850 if (pub
->version
== NULL
) pub
->version
= strdup(PDKIM_PUB_RECORD_VERSION
);
851 if (pub
->granularity
== NULL
) pub
->granularity
= strdup("*");
852 if (pub
->keytype
== NULL
) pub
->keytype
= strdup("rsa");
853 if (pub
->srvtype
== NULL
) pub
->srvtype
= strdup("*");
856 if (pub
->key
== NULL
) {
857 pdkim_free_pubkey(pub
);
865 /* -------------------------------------------------------------------------- */
866 int pdkim_update_bodyhash(pdkim_ctx
*ctx
, const char *data
, int len
) {
867 pdkim_signature
*sig
= ctx
->sig
;
868 /* Cache relaxed version of data */
869 char *relaxed_data
= NULL
;
872 /* Traverse all signatures, updating their hashes. */
873 while (sig
!= NULL
) {
874 /* Defaults to simple canon (no further treatment necessary) */
875 const char *canon_data
= data
;
878 if (sig
->canon_body
== PDKIM_CANON_RELAXED
) {
879 /* Relax the line if not done already */
880 if (relaxed_data
== NULL
) {
882 const char *p
= data
;
884 relaxed_data
= malloc(len
+1);
885 if (relaxed_data
== NULL
) return PDKIM_ERR_OOM
;
889 if ( (q
> 0) && (relaxed_data
[q
-1] == ' ') ) q
--;
891 else if ( (c
== '\t') || (c
== ' ') ) {
892 c
= ' '; /* Turns WSP into SP */
900 relaxed_data
[q
++] = c
;
903 relaxed_data
[q
] = '\0';
906 canon_data
= relaxed_data
;
907 canon_len
= relaxed_len
;
910 /* Make sure we don't exceed the to-be-signed body length */
911 if ((sig
->bodylength
>= 0) &&
912 ((sig
->signed_body_bytes
+(unsigned long)canon_len
) > sig
->bodylength
))
913 canon_len
= (sig
->bodylength
- sig
->signed_body_bytes
);
916 if (sig
->algo
== PDKIM_ALGO_RSA_SHA1
)
917 sha1_update(sig
->sha1_body
,(unsigned char *)canon_data
,canon_len
);
919 sha2_update(sig
->sha2_body
,(unsigned char *)canon_data
,canon_len
);
920 sig
->signed_body_bytes
+= canon_len
;
922 if (ctx
->debug_stream
!=NULL
)
923 pdkim_quoteprint(ctx
->debug_stream
,canon_data
,canon_len
,0);
930 if (relaxed_data
!= NULL
) free(relaxed_data
);
935 /* -------------------------------------------------------------------------- */
936 int pdkim_finish_bodyhash(pdkim_ctx
*ctx
) {
937 pdkim_signature
*sig
= ctx
->sig
;
939 /* Traverse all signatures */
940 while (sig
!= NULL
) {
943 unsigned char bh
[32]; /* SHA-256 = 32 Bytes, SHA-1 = 20 Bytes */
944 if (sig
->algo
== PDKIM_ALGO_RSA_SHA1
)
945 sha1_finish(sig
->sha1_body
,bh
);
947 sha2_finish(sig
->sha2_body
,bh
);
950 if (ctx
->debug_stream
) {
951 fprintf(ctx
->debug_stream
, "PDKIM [%s] Body bytes hashed: %lu\n",
952 sig
->domain
, sig
->signed_body_bytes
);
953 fprintf(ctx
->debug_stream
, "PDKIM [%s] bh computed: ", sig
->domain
);
954 pdkim_hexprint(ctx
->debug_stream
, (char *)bh
,
955 (sig
->algo
== PDKIM_ALGO_RSA_SHA1
)?20:32,1);
959 /* SIGNING -------------------------------------------------------------- */
960 if (ctx
->mode
== PDKIM_MODE_SIGN
) {
961 sig
->bodyhash_len
= (sig
->algo
== PDKIM_ALGO_RSA_SHA1
)?20:32;
962 sig
->bodyhash
= malloc(sig
->bodyhash_len
);
963 if (sig
->bodyhash
== NULL
) return PDKIM_ERR_OOM
;
964 memcpy(sig
->bodyhash
,bh
,sig
->bodyhash_len
);
966 /* If bodylength limit is set, and we have received less bytes
967 than the requested amount, effectively remove the limit tag. */
968 if (sig
->signed_body_bytes
< sig
->bodylength
) sig
->bodylength
= -1;
970 /* VERIFICATION --------------------------------------------------------- */
972 /* Compare bodyhash */
973 if (memcmp(bh
,sig
->bodyhash
,
974 (sig
->algo
== PDKIM_ALGO_RSA_SHA1
)?20:32) == 0) {
976 if (ctx
->debug_stream
)
977 fprintf(ctx
->debug_stream
, "PDKIM [%s] Body hash verified OK\n",
983 if (ctx
->debug_stream
) {
984 fprintf(ctx
->debug_stream
, "PDKIM [%s] Body hash did NOT verify\n",
986 fprintf(ctx
->debug_stream
, "PDKIM [%s] bh signature: ", sig
->domain
);
987 pdkim_hexprint(ctx
->debug_stream
, sig
->bodyhash
,
988 (sig
->algo
== PDKIM_ALGO_RSA_SHA1
)?20:32,1);
991 sig
->verify_status
= PDKIM_VERIFY_FAIL
;
992 sig
->verify_ext_status
= PDKIM_VERIFY_FAIL_BODY
;
1004 /* -------------------------------------------------------------------------- */
1005 /* Callback from pdkim_feed below for processing complete body lines */
1006 int pdkim_bodyline_complete(pdkim_ctx
*ctx
) {
1007 char *p
= ctx
->linebuf
;
1008 int n
= ctx
->linebuf_offset
;
1010 /* Ignore extra data if we've seen the end-of-data marker */
1011 if (ctx
->seen_eod
) goto BAIL
;
1013 /* We've always got one extra byte to stuff a zero ... */
1014 ctx
->linebuf
[(ctx
->linebuf_offset
)] = '\0';
1016 if (ctx
->input_mode
== PDKIM_INPUT_SMTP
) {
1017 /* Terminate on EOD marker */
1018 if (memcmp(p
,".\r\n",3) == 0) {
1023 if (memcmp(p
,"..",2) == 0) {
1029 /* Empty lines need to be buffered until we find a non-empty line */
1030 if (memcmp(p
,"\r\n",2) == 0) {
1031 ctx
->num_buffered_crlf
++;
1035 /* At this point, we have a non-empty line, so release the buffered ones. */
1036 while (ctx
->num_buffered_crlf
) {
1037 pdkim_update_bodyhash(ctx
,"\r\n",2);
1038 ctx
->num_buffered_crlf
--;
1041 pdkim_update_bodyhash(ctx
,p
,n
);
1044 ctx
->linebuf_offset
= 0;
1049 /* -------------------------------------------------------------------------- */
1050 /* Callback from pdkim_feed below for processing complete headers */
1051 #define DKIM_SIGNATURE_HEADERNAME "DKIM-Signature:"
1052 int pdkim_header_complete(pdkim_ctx
*ctx
) {
1053 pdkim_signature
*sig
= ctx
->sig
;
1055 /* Special case: The last header can have an extra \r appended */
1056 if ( (ctx
->cur_header
->len
> 1) &&
1057 (ctx
->cur_header
->str
[(ctx
->cur_header
->len
)-1] == '\r') ) {
1058 ctx
->cur_header
->str
[(ctx
->cur_header
->len
)-1] = '\0';
1059 ctx
->cur_header
->len
--;
1063 if (ctx
->num_headers
> PDKIM_MAX_HEADERS
) goto BAIL
;
1065 /* Traverse all signatures */
1066 while (sig
!= NULL
) {
1067 pdkim_stringlist
*list
;
1069 /* SIGNING -------------------------------------------------------------- */
1070 if (ctx
->mode
== PDKIM_MODE_SIGN
) {
1071 if (header_name_match(ctx
->cur_header
->str
,
1074 PDKIM_DEFAULT_SIGN_HEADERS
, 0) != PDKIM_OK
) goto NEXT_SIG
;
1076 /* VERIFICATION --------------------------------------------------------- */
1078 /* Header is not included or all instances were already 'ticked off' */
1079 if (header_name_match(ctx
->cur_header
->str
,
1080 sig
->hnames_check
, 1) != PDKIM_OK
) goto NEXT_SIG
;
1083 /* Add header to the signed headers list (in reverse order) */
1084 list
= pdkim_prepend_stringlist(sig
->headers
,
1085 ctx
->cur_header
->str
);
1086 if (list
== NULL
) return PDKIM_ERR_OOM
;
1087 sig
->headers
= list
;
1093 /* DKIM-Signature: headers are added to the verification list */
1094 if ( (ctx
->mode
== PDKIM_MODE_VERIFY
) &&
1095 (strncasecmp(ctx
->cur_header
->str
,
1096 DKIM_SIGNATURE_HEADERNAME
,
1097 strlen(DKIM_SIGNATURE_HEADERNAME
)) == 0) ) {
1098 pdkim_signature
*new_sig
;
1099 /* Create and chain new signature block */
1101 if (ctx
->debug_stream
)
1102 fprintf(ctx
->debug_stream
,
1103 "PDKIM >> Found sig, trying to parse >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
1105 new_sig
= pdkim_parse_sig_header(ctx
, ctx
->cur_header
->str
);
1106 if (new_sig
!= NULL
) {
1107 pdkim_signature
*last_sig
= ctx
->sig
;
1108 if (last_sig
== NULL
) {
1112 while (last_sig
->next
!= NULL
) { last_sig
= last_sig
->next
; }
1113 last_sig
->next
= new_sig
;
1118 if (ctx
->debug_stream
) {
1119 fprintf(ctx
->debug_stream
,"Error while parsing signature header\n");
1120 fprintf(ctx
->debug_stream
,
1121 "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
1128 pdkim_strclear(ctx
->cur_header
); /* Re-use existing pdkim_str */
1134 /* -------------------------------------------------------------------------- */
1135 #define HEADER_BUFFER_FRAG_SIZE 256
1136 DLLEXPORT
int pdkim_feed (pdkim_ctx
*ctx
,
1140 for (p
=0;p
<len
;p
++) {
1142 if (ctx
->past_headers
) {
1143 /* Processing body byte */
1144 ctx
->linebuf
[(ctx
->linebuf_offset
)++] = c
;
1146 int rc
= pdkim_bodyline_complete(ctx
); /* End of line */
1147 if (rc
!= PDKIM_OK
) return rc
;
1149 if (ctx
->linebuf_offset
== (PDKIM_MAX_BODY_LINE_LEN
-1))
1150 return PDKIM_ERR_LONG_LINE
;
1153 /* Processing header byte */
1157 int rc
= pdkim_header_complete(ctx
); /* Seen last header line */
1158 if (rc
!= PDKIM_OK
) return rc
;
1159 ctx
->past_headers
= 1;
1162 if (ctx
->debug_stream
)
1163 fprintf(ctx
->debug_stream
,
1164 "PDKIM >> Hashed body data, canonicalized >>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
1168 else ctx
->seen_lf
= 1;
1170 else if (ctx
->seen_lf
) {
1171 if (! ((c
== '\t') || (c
== ' '))) {
1172 int rc
= pdkim_header_complete(ctx
); /* End of header */
1173 if (rc
!= PDKIM_OK
) return rc
;
1178 if (ctx
->cur_header
== NULL
) {
1179 ctx
->cur_header
= pdkim_strnew(NULL
);
1180 if (ctx
->cur_header
== NULL
) return PDKIM_ERR_OOM
;
1182 if (ctx
->cur_header
->len
< PDKIM_MAX_HEADER_LEN
)
1183 if (pdkim_strncat(ctx
->cur_header
,&data
[p
],1) == NULL
)
1184 return PDKIM_ERR_OOM
;
1191 /* -------------------------------------------------------------------------- */
1192 char *pdkim_create_header(pdkim_signature
*sig
, int final
) {
1194 char *base64_bh
= NULL
;
1195 char *base64_b
= NULL
;
1196 pdkim_str
*hdr
= pdkim_strnew("DKIM-Signature: v="PDKIM_SIGNATURE_VERSION
);
1197 if (hdr
== NULL
) return NULL
;
1199 base64_bh
= pdkim_encode_base64(sig
->bodyhash
, sig
->bodyhash_len
);
1200 if (base64_bh
== NULL
) goto BAIL
;
1202 /* Required and static bits */
1204 pdkim_strcat(hdr
,"; a=") &&
1205 pdkim_strcat(hdr
,pdkim_algos
[sig
->algo
]) &&
1206 pdkim_strcat(hdr
,"; q=") &&
1207 pdkim_strcat(hdr
,pdkim_querymethods
[sig
->querymethod
]) &&
1208 pdkim_strcat(hdr
,"; c=") &&
1209 pdkim_strcat(hdr
,pdkim_canons
[sig
->canon_headers
]) &&
1210 pdkim_strcat(hdr
,"/") &&
1211 pdkim_strcat(hdr
,pdkim_canons
[sig
->canon_body
]) &&
1212 pdkim_strcat(hdr
,"; d=") &&
1213 pdkim_strcat(hdr
,sig
->domain
) &&
1214 pdkim_strcat(hdr
,"; s=") &&
1215 pdkim_strcat(hdr
,sig
->selector
) &&
1216 pdkim_strcat(hdr
,";\r\n\th=") &&
1217 pdkim_strcat(hdr
,sig
->headernames
) &&
1218 pdkim_strcat(hdr
,"; bh=") &&
1219 pdkim_strcat(hdr
,base64_bh
) &&
1220 pdkim_strcat(hdr
,";\r\n\t")
1223 if (sig
->identity
!= NULL
) {
1224 if (!( pdkim_strcat(hdr
,"i=") &&
1225 pdkim_strcat(hdr
,sig
->identity
) &&
1226 pdkim_strcat(hdr
,";") ) ) {
1230 if (sig
->created
> 0) {
1231 if (!( pdkim_strcat(hdr
,"t=") &&
1232 pdkim_numcat(hdr
,sig
->created
) &&
1233 pdkim_strcat(hdr
,";") ) ) {
1237 if (sig
->expires
> 0) {
1238 if (!( pdkim_strcat(hdr
,"x=") &&
1239 pdkim_numcat(hdr
,sig
->expires
) &&
1240 pdkim_strcat(hdr
,";") ) ) {
1244 if (sig
->bodylength
>= 0) {
1245 if (!( pdkim_strcat(hdr
,"l=") &&
1246 pdkim_numcat(hdr
,sig
->bodylength
) &&
1247 pdkim_strcat(hdr
,";") ) ) {
1251 /* Extra linebreak */
1252 if (hdr
->str
[(hdr
->len
)-1] == ';') {
1253 if (!pdkim_strcat(hdr
," \r\n\t")) goto BAIL
;
1255 /* Preliminary or final version? */
1257 base64_b
= pdkim_encode_base64(sig
->sigdata
, sig
->sigdata_len
);
1258 if (base64_b
== NULL
) goto BAIL
;
1260 pdkim_strcat(hdr
,"b=") &&
1261 pdkim_strcat(hdr
,base64_b
) &&
1262 pdkim_strcat(hdr
,";")
1266 if (pdkim_strcat(hdr
,"b=;")) goto DONE
;
1273 rc
= strdup(hdr
->str
);
1277 if (base64_bh
!= NULL
) free(base64_bh
);
1278 if (base64_b
!= NULL
) free(base64_b
);
1283 /* -------------------------------------------------------------------------- */
1284 DLLEXPORT
int pdkim_feed_finish(pdkim_ctx
*ctx
, pdkim_signature
**return_signatures
) {
1285 pdkim_signature
*sig
= ctx
->sig
;
1286 pdkim_str
*headernames
= NULL
; /* Collected signed header names */
1288 /* Check if we must still flush a (partial) header. If that is the
1289 case, the message has no body, and we must compute a body hash
1290 out of '<CR><LF>' */
1291 if (ctx
->cur_header
&& ctx
->cur_header
->len
) {
1292 int rc
= pdkim_header_complete(ctx
);
1293 if (rc
!= PDKIM_OK
) return rc
;
1294 pdkim_update_bodyhash(ctx
,"\r\n",2);
1297 /* For non-smtp input, check if there's an unfinished line in the
1298 body line buffer. If that is the case, we must add a CRLF to the
1299 hash to properly terminate the message. */
1300 if ((ctx
->input_mode
== PDKIM_INPUT_NORMAL
) && ctx
->linebuf_offset
) {
1301 pdkim_update_bodyhash(ctx
, ctx
->linebuf
, ctx
->linebuf_offset
);
1302 pdkim_update_bodyhash(ctx
,"\r\n",2);
1305 if (ctx
->debug_stream
)
1306 fprintf(ctx
->debug_stream
,
1307 "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
1311 /* Build (and/or evaluate) body hash */
1312 if (pdkim_finish_bodyhash(ctx
) != PDKIM_OK
) return PDKIM_ERR_OOM
;
1314 /* SIGNING -------------------------------------------------------------- */
1315 if (ctx
->mode
== PDKIM_MODE_SIGN
) {
1316 headernames
= pdkim_strnew(NULL
);
1317 if (headernames
== NULL
) return PDKIM_ERR_OOM
;
1319 /* ---------------------------------------------------------------------- */
1321 while (sig
!= NULL
) {
1322 sha1_context sha1_headers
;
1323 sha2_context sha2_headers
;
1325 char headerhash
[32];
1327 if (sig
->algo
== PDKIM_ALGO_RSA_SHA1
)
1328 sha1_starts(&sha1_headers
);
1330 sha2_starts(&sha2_headers
,0);
1333 if (ctx
->debug_stream
)
1334 fprintf(ctx
->debug_stream
,
1335 "PDKIM >> Hashed header data, canonicalized, in sequence >>>>>>>>>>>>>>\n");
1338 /* SIGNING ---------------------------------------------------------------- */
1339 /* When signing, walk through our header list and add them to the hash. As we
1340 go, construct a list of the header's names to use for the h= parameter. */
1341 if (ctx
->mode
== PDKIM_MODE_SIGN
) {
1342 pdkim_stringlist
*p
= sig
->headers
;
1345 /* Collect header names (Note: colon presence is guaranteed here) */
1346 char *q
= strchr(p
->value
,':');
1347 if (pdkim_strncat(headernames
, p
->value
,
1348 (q
-(p
->value
))+((p
->next
==NULL
)?0:1)) == NULL
)
1349 return PDKIM_ERR_OOM
;
1351 if (sig
->canon_headers
== PDKIM_CANON_RELAXED
)
1352 rh
= pdkim_relax_header(p
->value
,1); /* cook header for relaxed canon */
1354 rh
= strdup(p
->value
); /* just copy it for simple canon */
1356 if (rh
== NULL
) return PDKIM_ERR_OOM
;
1358 /* Feed header to the hash algorithm */
1359 if (sig
->algo
== PDKIM_ALGO_RSA_SHA1
)
1360 sha1_update(&(sha1_headers
),(unsigned char *)rh
,strlen(rh
));
1362 sha2_update(&(sha2_headers
),(unsigned char *)rh
,strlen(rh
));
1364 if (ctx
->debug_stream
)
1365 pdkim_quoteprint(ctx
->debug_stream
, rh
, strlen(rh
), 1);
1371 /* VERIFICATION ----------------------------------------------------------- */
1372 /* When verifying, walk through the header name list in the h= parameter and
1373 add the headers to the hash in that order. */
1375 char *b
= strdup(sig
->headernames
);
1378 if (b
== NULL
) return PDKIM_ERR_OOM
;
1381 pdkim_stringlist
*hdrs
= sig
->headers
;
1383 if (q
!= NULL
) *q
= '\0';
1384 while (hdrs
!= NULL
) {
1385 if ( (strncasecmp(hdrs
->value
,p
,strlen(p
)) == 0) &&
1386 ((hdrs
->value
)[strlen(p
)] == ':') ) {
1388 if (sig
->canon_headers
== PDKIM_CANON_RELAXED
)
1389 rh
= pdkim_relax_header(hdrs
->value
,1); /* cook header for relaxed canon */
1391 rh
= strdup(hdrs
->value
); /* just copy it for simple canon */
1392 if (rh
== NULL
) return PDKIM_ERR_OOM
;
1393 /* Feed header to the hash algorithm */
1394 if (sig
->algo
== PDKIM_ALGO_RSA_SHA1
)
1395 sha1_update(&(sha1_headers
),(unsigned char *)rh
,strlen(rh
));
1397 sha2_update(&(sha2_headers
),(unsigned char *)rh
,strlen(rh
));
1399 if (ctx
->debug_stream
)
1400 pdkim_quoteprint(ctx
->debug_stream
, rh
, strlen(rh
), 1);
1403 (hdrs
->value
)[0] = '_';
1408 if (q
== NULL
) break;
1415 if (ctx
->debug_stream
)
1416 fprintf(ctx
->debug_stream
,
1417 "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
1420 /* SIGNING ---------------------------------------------------------------- */
1421 if (ctx
->mode
== PDKIM_MODE_SIGN
) {
1422 /* Copy headernames to signature struct */
1423 sig
->headernames
= strdup(headernames
->str
);
1424 pdkim_strfree(headernames
);
1426 /* Create signature header with b= omitted */
1427 sig_hdr
= pdkim_create_header(ctx
->sig
,0);
1429 /* VERIFICATION ----------------------------------------------------------- */
1431 sig_hdr
= strdup(sig
->rawsig_no_b_val
);
1433 /* ------------------------------------------------------------------------ */
1435 if (sig_hdr
== NULL
) return PDKIM_ERR_OOM
;
1437 /* Relax header if necessary */
1438 if (sig
->canon_headers
== PDKIM_CANON_RELAXED
) {
1439 char *relaxed_hdr
= pdkim_relax_header(sig_hdr
,0);
1441 if (relaxed_hdr
== NULL
) return PDKIM_ERR_OOM
;
1442 sig_hdr
= relaxed_hdr
;
1446 if (ctx
->debug_stream
) {
1447 fprintf(ctx
->debug_stream
,
1448 "PDKIM >> Signed DKIM-Signature header, canonicalized >>>>>>>>>>>>>>>>>\n");
1449 pdkim_quoteprint(ctx
->debug_stream
, sig_hdr
, strlen(sig_hdr
), 1);
1450 fprintf(ctx
->debug_stream
,
1451 "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
1455 /* Finalize header hash */
1456 if (sig
->algo
== PDKIM_ALGO_RSA_SHA1
) {
1457 sha1_update(&(sha1_headers
),(unsigned char *)sig_hdr
,strlen(sig_hdr
));
1458 sha1_finish(&(sha1_headers
),(unsigned char *)headerhash
);
1460 if (ctx
->debug_stream
) {
1461 fprintf(ctx
->debug_stream
, "PDKIM [%s] hh computed: ", sig
->domain
);
1462 pdkim_hexprint(ctx
->debug_stream
, headerhash
, 20, 1);
1467 sha2_update(&(sha2_headers
),(unsigned char *)sig_hdr
,strlen(sig_hdr
));
1468 sha2_finish(&(sha2_headers
),(unsigned char *)headerhash
);
1470 if (ctx
->debug_stream
) {
1471 fprintf(ctx
->debug_stream
, "PDKIM [%s] hh computed: ", sig
->domain
);
1472 pdkim_hexprint(ctx
->debug_stream
, headerhash
, 32, 1);
1479 /* SIGNING ---------------------------------------------------------------- */
1480 if (ctx
->mode
== PDKIM_MODE_SIGN
) {
1483 rsa_init(&rsa
,RSA_PKCS_V15
,0);
1485 /* Perform private key operation */
1486 if (rsa_parse_key(&rsa
, (unsigned char *)sig
->rsa_privkey
,
1487 strlen(sig
->rsa_privkey
), NULL
, 0) != 0) {
1488 return PDKIM_ERR_RSA_PRIVKEY
;
1491 sig
->sigdata_len
= mpi_size(&(rsa
.N
));
1492 sig
->sigdata
= malloc(sig
->sigdata_len
);
1493 if (sig
->sigdata
== NULL
) return PDKIM_ERR_OOM
;
1495 if (rsa_pkcs1_sign( &rsa
, RSA_PRIVATE
,
1496 ((sig
->algo
== PDKIM_ALGO_RSA_SHA1
)?
1497 SIG_RSA_SHA1
:SIG_RSA_SHA256
),
1499 (unsigned char *)headerhash
,
1500 (unsigned char *)sig
->sigdata
) != 0) {
1501 return PDKIM_ERR_RSA_SIGNING
;
1507 if (ctx
->debug_stream
) {
1508 fprintf(ctx
->debug_stream
, "PDKIM [%s] b computed: ",
1510 pdkim_hexprint(ctx
->debug_stream
, sig
->sigdata
, sig
->sigdata_len
, 1);
1514 sig
->signature_header
= pdkim_create_header(ctx
->sig
,1);
1515 if (sig
->signature_header
== NULL
) return PDKIM_ERR_OOM
;
1517 /* VERIFICATION ----------------------------------------------------------- */
1520 char *dns_txt_name
, *dns_txt_reply
;
1522 rsa_init(&rsa
,RSA_PKCS_V15
,0);
1524 dns_txt_name
= malloc(PDKIM_DNS_TXT_MAX_NAMELEN
);
1525 if (dns_txt_name
== NULL
) return PDKIM_ERR_OOM
;
1526 dns_txt_reply
= malloc(PDKIM_DNS_TXT_MAX_RECLEN
);
1527 if (dns_txt_reply
== NULL
) {
1529 return PDKIM_ERR_OOM
;
1531 memset(dns_txt_reply
,0,PDKIM_DNS_TXT_MAX_RECLEN
);
1532 memset(dns_txt_name
,0,PDKIM_DNS_TXT_MAX_NAMELEN
);
1534 if (snprintf(dns_txt_name
,PDKIM_DNS_TXT_MAX_NAMELEN
,
1535 "%s._domainkey.%s.",
1536 sig
->selector
,sig
->domain
) >= PDKIM_DNS_TXT_MAX_NAMELEN
) {
1537 sig
->verify_status
= PDKIM_VERIFY_INVALID
;
1538 sig
->verify_ext_status
= PDKIM_VERIFY_INVALID_BUFFER_SIZE
;
1542 if ((ctx
->dns_txt_callback(dns_txt_name
, dns_txt_reply
) != PDKIM_OK
) ||
1543 (dns_txt_reply
[0] == '\0')) {
1544 sig
->verify_status
= PDKIM_VERIFY_INVALID
;
1545 sig
->verify_ext_status
= PDKIM_VERIFY_INVALID_PUBKEY_UNAVAILABLE
;
1550 if (ctx
->debug_stream
) {
1551 fprintf(ctx
->debug_stream
,
1552 "PDKIM >> Parsing public key record >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
1553 fprintf(ctx
->debug_stream
,"Raw record: ");
1554 pdkim_quoteprint(ctx
->debug_stream
, dns_txt_reply
, strlen(dns_txt_reply
), 1);
1558 sig
->pubkey
= pdkim_parse_pubkey_record(ctx
,dns_txt_reply
);
1559 if (sig
->pubkey
== NULL
) {
1560 sig
->verify_status
= PDKIM_VERIFY_INVALID
;
1561 sig
->verify_ext_status
= PDKIM_VERIFY_INVALID_PUBKEY_PARSING
;
1563 if (ctx
->debug_stream
) {
1564 fprintf(ctx
->debug_stream
,"Error while parsing public key record\n");
1565 fprintf(ctx
->debug_stream
,
1566 "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
1573 if (ctx
->debug_stream
) {
1574 fprintf(ctx
->debug_stream
,
1575 "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
1579 if (rsa_parse_public_key(&rsa
,
1580 (unsigned char *)sig
->pubkey
->key
,
1581 sig
->pubkey
->key_len
) != 0) {
1582 sig
->verify_status
= PDKIM_VERIFY_INVALID
;
1583 sig
->verify_ext_status
= PDKIM_VERIFY_INVALID_PUBKEY_PARSING
;
1587 /* Check the signature */
1588 if (rsa_pkcs1_verify(&rsa
,
1590 ((sig
->algo
== PDKIM_ALGO_RSA_SHA1
)?
1591 SIG_RSA_SHA1
:SIG_RSA_SHA256
),
1593 (unsigned char *)headerhash
,
1594 (unsigned char *)sig
->sigdata
) != 0) {
1595 sig
->verify_status
= PDKIM_VERIFY_FAIL
;
1596 sig
->verify_ext_status
= PDKIM_VERIFY_FAIL_MESSAGE
;
1600 /* We have a winner! (if bodydhash was correct earlier) */
1601 if (sig
->verify_status
== PDKIM_VERIFY_NONE
) {
1602 sig
->verify_status
= PDKIM_VERIFY_PASS
;
1608 if (ctx
->debug_stream
) {
1609 fprintf(ctx
->debug_stream
, "PDKIM [%s] signature status: %s",
1610 sig
->domain
, pdkim_verify_status_str(sig
->verify_status
));
1611 if (sig
->verify_ext_status
> 0) {
1612 fprintf(ctx
->debug_stream
, " (%s)\n",
1613 pdkim_verify_ext_status_str(sig
->verify_ext_status
));
1616 fprintf(ctx
->debug_stream
, "\n");
1623 free(dns_txt_reply
);
1629 /* If requested, set return pointer to signature(s) */
1630 if (return_signatures
!= NULL
) {
1631 *return_signatures
= ctx
->sig
;
1638 /* -------------------------------------------------------------------------- */
1639 DLLEXPORT pdkim_ctx
*pdkim_init_verify(int input_mode
,
1640 int(*dns_txt_callback
)(char *, char *)
1642 pdkim_ctx
*ctx
= malloc(sizeof(pdkim_ctx
));
1643 if (ctx
== NULL
) return NULL
;
1644 memset(ctx
,0,sizeof(pdkim_ctx
));
1646 ctx
->linebuf
= malloc(PDKIM_MAX_BODY_LINE_LEN
);
1647 if (ctx
->linebuf
== NULL
) {
1652 ctx
->mode
= PDKIM_MODE_VERIFY
;
1653 ctx
->input_mode
= input_mode
;
1654 ctx
->dns_txt_callback
= dns_txt_callback
;
1660 /* -------------------------------------------------------------------------- */
1661 DLLEXPORT pdkim_ctx
*pdkim_init_sign(int input_mode
,
1664 char *rsa_privkey
) {
1666 pdkim_signature
*sig
;
1668 if (!domain
|| !selector
|| !rsa_privkey
) return NULL
;
1670 ctx
= malloc(sizeof(pdkim_ctx
));
1671 if (ctx
== NULL
) return NULL
;
1672 memset(ctx
,0,sizeof(pdkim_ctx
));
1674 ctx
->linebuf
= malloc(PDKIM_MAX_BODY_LINE_LEN
);
1675 if (ctx
->linebuf
== NULL
) {
1680 sig
= malloc(sizeof(pdkim_signature
));
1686 memset(sig
,0,sizeof(pdkim_signature
));
1687 sig
->bodylength
= -1;
1689 ctx
->mode
= PDKIM_MODE_SIGN
;
1690 ctx
->input_mode
= input_mode
;
1693 ctx
->sig
->domain
= strdup(domain
);
1694 ctx
->sig
->selector
= strdup(selector
);
1695 ctx
->sig
->rsa_privkey
= strdup(rsa_privkey
);
1697 if (!ctx
->sig
->domain
|| !ctx
->sig
->selector
|| !ctx
->sig
->rsa_privkey
) {
1698 pdkim_free_ctx(ctx
);
1702 ctx
->sig
->sha1_body
= malloc(sizeof(sha1_context
));
1703 if (ctx
->sig
->sha1_body
== NULL
) {
1704 pdkim_free_ctx(ctx
);
1707 sha1_starts(ctx
->sig
->sha1_body
);
1709 ctx
->sig
->sha2_body
= malloc(sizeof(sha2_context
));
1710 if (ctx
->sig
->sha2_body
== NULL
) {
1711 pdkim_free_ctx(ctx
);
1714 sha2_starts(ctx
->sig
->sha2_body
,0);
1720 /* -------------------------------------------------------------------------- */
1721 DLLEXPORT
void pdkim_set_debug_stream(pdkim_ctx
*ctx
,
1722 FILE *debug_stream
) {
1723 ctx
->debug_stream
= debug_stream
;
1727 /* -------------------------------------------------------------------------- */
1728 DLLEXPORT
int pdkim_set_optional(pdkim_ctx
*ctx
,
1735 unsigned long created
,
1736 unsigned long expires
) {
1738 if (identity
!= NULL
) {
1739 ctx
->sig
->identity
= strdup(identity
);
1740 if (ctx
->sig
->identity
== NULL
) return PDKIM_ERR_OOM
;
1743 if (sign_headers
!= NULL
) {
1744 ctx
->sig
->sign_headers
= strdup(sign_headers
);
1745 if (ctx
->sig
->sign_headers
== NULL
) return PDKIM_ERR_OOM
;
1748 ctx
->sig
->canon_headers
= canon_headers
;
1749 ctx
->sig
->canon_body
= canon_body
;
1750 ctx
->sig
->bodylength
= bodylength
;
1751 ctx
->sig
->algo
= algo
;
1752 ctx
->sig
->created
= created
;
1753 ctx
->sig
->expires
= expires
;