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.
23 /* $Cambridge: exim/src/src/pdkim/pdkim.c,v 1.3 2009/09/09 08:13:58 tom Exp $ */
37 #define PDKIM_SIGNATURE_VERSION "1"
38 #define PDKIM_PUB_RECORD_VERSION "DKIM1"
40 #define PDKIM_MAX_HEADER_LEN 65536
41 #define PDKIM_MAX_HEADERS 512
42 #define PDKIM_MAX_BODY_LINE_LEN 16384
43 #define PDKIM_DNS_TXT_MAX_NAMELEN 1024
44 #define PDKIM_DEFAULT_SIGN_HEADERS "From:Sender:Reply-To:Subject:Date:"\
45 "Message-ID:To:Cc:MIME-Version:Content-Type:"\
46 "Content-Transfer-Encoding:Content-ID:"\
47 "Content-Description:Resent-Date:Resent-From:"\
48 "Resent-Sender:Resent-To:Resent-Cc:"\
49 "Resent-Message-ID:In-Reply-To:References:"\
50 "List-Id:List-Help:List-Unsubscribe:"\
51 "List-Subscribe:List-Post:List-Owner:List-Archive"
53 /* -------------------------------------------------------------------------- */
54 struct pdkim_stringlist
{
59 #define PDKIM_STR_ALLOC_FRAG 256
63 unsigned int allocated
;
66 /* -------------------------------------------------------------------------- */
67 /* A bunch of list constants */
68 char *pdkim_querymethods
[] = {
72 char *pdkim_algos
[] = {
77 char *pdkim_canons
[] = {
82 char *pdkim_hashes
[] = {
87 char *pdkim_keytypes
[] = {
92 typedef struct pdkim_combined_canon_entry
{
96 } pdkim_combined_canon_entry
;
97 pdkim_combined_canon_entry pdkim_combined_canons
[] = {
98 { "simple/simple", PDKIM_CANON_SIMPLE
, PDKIM_CANON_SIMPLE
},
99 { "simple/relaxed", PDKIM_CANON_SIMPLE
, PDKIM_CANON_RELAXED
},
100 { "relaxed/simple", PDKIM_CANON_RELAXED
, PDKIM_CANON_SIMPLE
},
101 { "relaxed/relaxed", PDKIM_CANON_RELAXED
, PDKIM_CANON_RELAXED
},
102 { "simple", PDKIM_CANON_SIMPLE
, PDKIM_CANON_SIMPLE
},
103 { "relaxed", PDKIM_CANON_RELAXED
, PDKIM_CANON_SIMPLE
},
108 /* -------------------------------------------------------------------------- */
109 /* Print debugging functions */
111 void pdkim_quoteprint(FILE *stream
, char *data
, int len
, int lf
) {
113 unsigned char *p
= (unsigned char *)data
;
115 for (i
=0;i
<len
;i
++) {
118 case ' ' : fprintf(stream
,"{SP}"); break;
119 case '\t': fprintf(stream
,"{TB}"); break;
120 case '\r': fprintf(stream
,"{CR}"); break;
121 case '\n': fprintf(stream
,"{LF}"); break;
122 case '{' : fprintf(stream
,"{BO}"); break;
123 case '}' : fprintf(stream
,"{BC}"); break;
125 if ( (c
< 32) || (c
> 127) )
126 fprintf(stream
,"{%02x}",c
);
135 void pdkim_hexprint(FILE *stream
, char *data
, int len
, int lf
) {
137 unsigned char *p
= (unsigned char *)data
;
139 for (i
=0;i
<len
;i
++) {
141 fprintf(stream
,"%02x",c
);
149 /* -------------------------------------------------------------------------- */
150 /* Simple string list implementation for convinience */
151 pdkim_stringlist
*pdkim_append_stringlist(pdkim_stringlist
*base
, char *str
) {
152 pdkim_stringlist
*new_entry
= malloc(sizeof(pdkim_stringlist
));
153 if (new_entry
== NULL
) return NULL
;
154 memset(new_entry
,0,sizeof(pdkim_stringlist
));
155 new_entry
->value
= strdup(str
);
156 if (new_entry
->value
== NULL
) return NULL
;
158 pdkim_stringlist
*last
= base
;
159 while (last
->next
!= NULL
) { last
= last
->next
; };
160 last
->next
= new_entry
;
163 else return new_entry
;
165 pdkim_stringlist
*pdkim_prepend_stringlist(pdkim_stringlist
*base
, char *str
) {
166 pdkim_stringlist
*new_entry
= malloc(sizeof(pdkim_stringlist
));
167 if (new_entry
== NULL
) return NULL
;
168 memset(new_entry
,0,sizeof(pdkim_stringlist
));
169 new_entry
->value
= strdup(str
);
170 if (new_entry
->value
== NULL
) return NULL
;
172 new_entry
->next
= base
;
178 /* -------------------------------------------------------------------------- */
179 /* A small "growing string" implementation to escape malloc/realloc hell */
180 pdkim_str
*pdkim_strnew (char *cstr
) {
181 unsigned int len
= cstr
?strlen(cstr
):0;
182 pdkim_str
*p
= malloc(sizeof(pdkim_str
));
183 if (p
== NULL
) return NULL
;
184 memset(p
,0,sizeof(pdkim_str
));
185 p
->str
= malloc(len
+1);
186 if (p
->str
== NULL
) {
190 p
->allocated
=(len
+1);
192 if (cstr
) strcpy(p
->str
,cstr
);
195 char *pdkim_strncat(pdkim_str
*str
, char *data
, int len
) {
196 if ((str
->allocated
- str
->len
) < (len
+1)) {
197 /* Extend the buffer */
198 int num_frags
= ((len
+1)/PDKIM_STR_ALLOC_FRAG
)+1;
199 char *n
= realloc(str
->str
,
200 (str
->allocated
+(num_frags
*PDKIM_STR_ALLOC_FRAG
)));
201 if (n
== NULL
) return NULL
;
203 str
->allocated
+= (num_frags
*PDKIM_STR_ALLOC_FRAG
);
205 strncpy(&(str
->str
[str
->len
]),data
,len
);
207 str
->str
[str
->len
] = '\0';
210 char *pdkim_strcat(pdkim_str
*str
, char *cstr
) {
211 return pdkim_strncat(str
, cstr
, strlen(cstr
));
213 char *pdkim_numcat(pdkim_str
*str
, unsigned long num
) {
215 snprintf(minibuf
,20,"%lu",num
);
216 return pdkim_strcat(str
,minibuf
);
218 char *pdkim_strtrim(pdkim_str
*str
) {
221 while ( (*p
!= '\0') && ((*p
== '\t') || (*p
== ' ')) ) p
++;
222 while (*p
!= '\0') {*q
= *p
; q
++; p
++;};
224 while ( (q
!= str
->str
) && ( (*q
== '\0') || (*q
== '\t') || (*q
== ' ') ) ) {
228 str
->len
= strlen(str
->str
);
231 char *pdkim_strclear(pdkim_str
*str
) {
236 void pdkim_strfree(pdkim_str
*str
) {
237 if (str
== NULL
) return;
238 if (str
->str
!= NULL
) free(str
->str
);
244 /* -------------------------------------------------------------------------- */
245 void pdkim_free_pubkey(pdkim_pubkey
*pub
) {
247 if (pub
->version
!= NULL
) free(pub
->version
);
248 if (pub
->granularity
!= NULL
) free(pub
->granularity
);
249 if (pub
->hashes
!= NULL
) free(pub
->hashes
);
250 if (pub
->keytype
!= NULL
) free(pub
->keytype
);
251 if (pub
->srvtype
!= NULL
) free(pub
->srvtype
);
252 if (pub
->notes
!= NULL
) free(pub
->notes
);
253 if (pub
->key
!= NULL
) free(pub
->key
);
259 /* -------------------------------------------------------------------------- */
260 void pdkim_free_sig(pdkim_signature
*sig
) {
262 pdkim_signature
*next
= (pdkim_signature
*)sig
->next
;
264 pdkim_stringlist
*e
= sig
->headers
;
266 pdkim_stringlist
*c
= e
;
267 if (e
->value
!= NULL
) free(e
->value
);
272 if (sig
->sigdata
!= NULL
) free(sig
->sigdata
);
273 if (sig
->bodyhash
!= NULL
) free(sig
->bodyhash
);
274 if (sig
->selector
!= NULL
) free(sig
->selector
);
275 if (sig
->domain
!= NULL
) free(sig
->domain
);
276 if (sig
->identity
!= NULL
) free(sig
->identity
);
277 if (sig
->headernames
!= NULL
) free(sig
->headernames
);
278 if (sig
->copiedheaders
!= NULL
) free(sig
->copiedheaders
);
279 if (sig
->rsa_privkey
!= NULL
) free(sig
->rsa_privkey
);
280 if (sig
->sign_headers
!= NULL
) free(sig
->sign_headers
);
281 if (sig
->signature_header
!= NULL
) free(sig
->signature_header
);
282 if (sig
->sha1_body
!= NULL
) free(sig
->sha1_body
);
283 if (sig
->sha2_body
!= NULL
) free(sig
->sha2_body
);
284 if (sig
->hnames_check
!= NULL
) free(sig
->hnames_check
);
286 if (sig
->pubkey
!= NULL
) pdkim_free_pubkey(sig
->pubkey
);
289 if (next
!= NULL
) pdkim_free_sig(next
);
294 /* -------------------------------------------------------------------------- */
295 DLLEXPORT
void pdkim_free_ctx(pdkim_ctx
*ctx
) {
297 pdkim_free_sig(ctx
->sig
);
298 pdkim_strfree(ctx
->cur_header
);
304 /* -------------------------------------------------------------------------- */
305 /* Matches the name of the passed raw "header" against
306 the passed colon-separated "list", starting at entry
307 "start". Returns the position of the header name in
309 int header_name_match(char *header
,
318 /* Get header name */
319 char *hcolon
= strchr(header
,':');
320 if (hcolon
== NULL
) return rc
; /* This isn't a header */
321 hname
= malloc((hcolon
-header
)+1);
322 if (hname
== NULL
) return PDKIM_ERR_OOM
;
323 memset(hname
,0,(hcolon
-header
)+1);
324 strncpy(hname
,header
,(hcolon
-header
));
326 /* Copy tick-off list locally, so we can punch zeroes into it */
327 lcopy
= strdup(tick
);
330 return PDKIM_ERR_OOM
;
337 if (strcasecmp(p
,hname
) == 0) {
339 /* Invalidate header name instance in tick-off list */
340 if (do_tick
) tick
[p
-lcopy
] = '_';
348 if (strcasecmp(p
,hname
) == 0) {
350 /* Invalidate header name instance in tick-off list */
351 if (do_tick
) tick
[p
-lcopy
] = '_';
361 /* -------------------------------------------------------------------------- */
362 /* Performs "relaxed" canonicalization of a header. The returned pointer needs
364 char *pdkim_relax_header (char *header
, int crlf
) {
365 int past_field_name
= 0;
369 char *relaxed
= malloc(strlen(header
));
370 if (relaxed
== NULL
) return NULL
;
375 if ( (c
== '\r') || (c
== '\n') ) {
379 if ( (c
== '\t') || (c
== ' ') ) {
380 c
= ' '; /* Turns WSP into SP */
388 if ( (!past_field_name
) && (c
== ':') ) {
389 if (seen_wsp
) q
--; /* This removes WSP before the colon */
390 seen_wsp
= 1; /* This removes WSP after the colon */
395 /* Lowercase header name */
396 if (!past_field_name
) c
= tolower(c
);
402 if (crlf
) strcat(relaxed
,"\r\n");
407 /* -------------------------------------------------------------------------- */
408 #define PDKIM_QP_ERROR_DECODE -1
409 char *pdkim_decode_qp_char(char *qp_p
, int *c
) {
410 char *initial_pos
= qp_p
;
412 /* Advance one char */
415 /* Check for two hex digits and decode them */
416 if (isxdigit(*qp_p
) && isxdigit(qp_p
[1])) {
417 /* Do hex conversion */
418 if (isdigit(*qp_p
)) {*c
= *qp_p
- '0';}
419 else {*c
= toupper(*qp_p
) - 'A' + 10;};
421 if (isdigit(qp_p
[1])) {*c
|= qp_p
[1] - '0';}
422 else {*c
|= toupper(qp_p
[1]) - 'A' + 10;};
426 /* Illegal char here */
427 *c
= PDKIM_QP_ERROR_DECODE
;
432 /* -------------------------------------------------------------------------- */
433 char *pdkim_decode_qp(char *str
) {
437 char *n
= malloc(strlen(p
)+1);
438 if (n
== NULL
) return NULL
;
443 p
= pdkim_decode_qp_char(p
,&nchar
);
461 /* -------------------------------------------------------------------------- */
462 char *pdkim_decode_base64(char *str
, int *num_decoded
) {
466 base64_decode(NULL
, &dlen
, (unsigned char *)str
, strlen(str
));
467 res
= malloc(dlen
+1);
468 if (res
== NULL
) return NULL
;
469 if (base64_decode((unsigned char *)res
,&dlen
,(unsigned char *)str
,strlen(str
)) != 0) {
473 if (num_decoded
!= NULL
) *num_decoded
= dlen
;
477 /* -------------------------------------------------------------------------- */
478 char *pdkim_encode_base64(char *str
, int num
) {
482 base64_encode(NULL
, &dlen
, (unsigned char *)str
, num
);
483 res
= malloc(dlen
+1);
484 if (res
== NULL
) return NULL
;
485 if (base64_encode((unsigned char *)res
,&dlen
,(unsigned char *)str
,num
) != 0) {
493 /* -------------------------------------------------------------------------- */
494 #define PDKIM_HDR_LIMBO 0
495 #define PDKIM_HDR_TAG 1
496 #define PDKIM_HDR_VALUE 2
497 pdkim_signature
*pdkim_parse_sig_header(pdkim_ctx
*ctx
, char *raw_hdr
) {
498 pdkim_signature
*sig
;
500 pdkim_str
*cur_tag
= NULL
;
501 pdkim_str
*cur_val
= NULL
;
504 int where
= PDKIM_HDR_LIMBO
;
507 sig
= malloc(sizeof(pdkim_signature
));
508 if (sig
== NULL
) return NULL
;
509 memset(sig
,0,sizeof(pdkim_signature
));
510 sig
->bodylength
= -1;
512 sig
->rawsig_no_b_val
= malloc(strlen(raw_hdr
)+1);
513 if (sig
->rawsig_no_b_val
== NULL
) {
519 q
= sig
->rawsig_no_b_val
;
524 if ( (*p
== '\r') || (*p
== '\n') )
527 /* Fast-forward through header name */
529 if (*p
== ':') past_hname
= 1;
533 if (where
== PDKIM_HDR_LIMBO
) {
534 /* In limbo, just wait for a tag-char to appear */
535 if (!((*p
>= 'a') && (*p
<= 'z')))
538 where
= PDKIM_HDR_TAG
;
541 if (where
== PDKIM_HDR_TAG
) {
543 cur_tag
= pdkim_strnew(NULL
);
545 if ((*p
>= 'a') && (*p
<= 'z'))
546 pdkim_strncat(cur_tag
,p
,1);
549 if (strcmp(cur_tag
->str
,"b") == 0) {
553 where
= PDKIM_HDR_VALUE
;
558 if (where
== PDKIM_HDR_VALUE
) {
560 cur_val
= pdkim_strnew(NULL
);
562 if ( (*p
== '\r') || (*p
== '\n') || (*p
== ' ') || (*p
== '\t') )
565 if ( (*p
== ';') || (*p
== '\0') ) {
566 if (cur_tag
->len
> 0) {
567 pdkim_strtrim(cur_val
);
569 if (ctx
->debug_stream
)
570 fprintf(ctx
->debug_stream
, "%s=%s\n", cur_tag
->str
, cur_val
->str
);
572 switch (cur_tag
->str
[0]) {
574 switch (cur_tag
->str
[1]) {
576 sig
->bodyhash
= pdkim_decode_base64(cur_val
->str
,&(sig
->bodyhash_len
));
579 sig
->sigdata
= pdkim_decode_base64(cur_val
->str
,&(sig
->sigdata_len
));
584 if (strcmp(cur_val
->str
,PDKIM_SIGNATURE_VERSION
) == 0) {
585 /* We only support version 1, and that is currently the
586 only version there is. */
592 while (pdkim_algos
[i
] != NULL
) {
593 if (strcmp(cur_val
->str
,pdkim_algos
[i
]) == 0 ) {
602 while (pdkim_combined_canons
[i
].str
!= NULL
) {
603 if (strcmp(cur_val
->str
,pdkim_combined_canons
[i
].str
) == 0 ) {
604 sig
->canon_headers
= pdkim_combined_canons
[i
].canon_headers
;
605 sig
->canon_body
= pdkim_combined_canons
[i
].canon_body
;
613 while (pdkim_querymethods
[i
] != NULL
) {
614 if (strcmp(cur_val
->str
,pdkim_querymethods
[i
]) == 0 ) {
615 sig
->querymethod
= i
;
622 sig
->selector
= strdup(cur_val
->str
);
625 sig
->domain
= strdup(cur_val
->str
);
628 sig
->identity
= pdkim_decode_qp(cur_val
->str
);
631 sig
->created
= strtoul(cur_val
->str
,NULL
,10);
634 sig
->expires
= strtoul(cur_val
->str
,NULL
,10);
637 sig
->bodylength
= strtol(cur_val
->str
,NULL
,10);
640 sig
->headernames
= strdup(cur_val
->str
);
643 sig
->copiedheaders
= pdkim_decode_qp(cur_val
->str
);
647 if (ctx
->debug_stream
)
648 fprintf(ctx
->debug_stream
, "Unknown tag encountered\n");
653 pdkim_strclear(cur_tag
);
654 pdkim_strclear(cur_val
);
656 where
= PDKIM_HDR_LIMBO
;
659 else pdkim_strncat(cur_val
,p
,1);
663 if (*p
== '\0') break;
672 /* Make sure the most important bits are there. */
673 if (!(sig
->domain
&& (*(sig
->domain
) != '\0') &&
674 sig
->selector
&& (*(sig
->selector
) != '\0') &&
675 sig
->headernames
&& (*(sig
->headernames
) != '\0') &&
683 /* Copy header list to 'tick-off' header list */
684 sig
->hnames_check
= strdup(sig
->headernames
);
687 /* Chomp raw header. The final newline must not be added to the signature. */
689 while( (q
> sig
->rawsig_no_b_val
) && ((*q
== '\r') || (*q
== '\n')) ) {
694 if (ctx
->debug_stream
) {
695 fprintf(ctx
->debug_stream
,
696 "PDKIM >> Raw signature w/o b= tag value >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
697 pdkim_quoteprint(ctx
->debug_stream
,
698 sig
->rawsig_no_b_val
,
699 strlen(sig
->rawsig_no_b_val
), 1);
700 fprintf(ctx
->debug_stream
,
701 "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
705 sig
->sha1_body
= malloc(sizeof(sha1_context
));
706 if (sig
->sha1_body
== NULL
) {
710 sig
->sha2_body
= malloc(sizeof(sha2_context
));
711 if (sig
->sha2_body
== NULL
) {
716 sha1_starts(sig
->sha1_body
);
717 sha2_starts(sig
->sha2_body
,0);
723 /* -------------------------------------------------------------------------- */
724 pdkim_pubkey
*pdkim_parse_pubkey_record(pdkim_ctx
*ctx
, char *raw_record
) {
727 pdkim_str
*cur_tag
= NULL
;
728 pdkim_str
*cur_val
= NULL
;
729 int where
= PDKIM_HDR_LIMBO
;
731 pub
= malloc(sizeof(pdkim_pubkey
));
732 if (pub
== NULL
) return NULL
;
733 memset(pub
,0,sizeof(pdkim_pubkey
));
740 if ( (*p
== '\r') || (*p
== '\n') )
743 if (where
== PDKIM_HDR_LIMBO
) {
744 /* In limbo, just wait for a tag-char to appear */
745 if (!((*p
>= 'a') && (*p
<= 'z')))
748 where
= PDKIM_HDR_TAG
;
751 if (where
== PDKIM_HDR_TAG
) {
753 cur_tag
= pdkim_strnew(NULL
);
755 if ((*p
>= 'a') && (*p
<= 'z'))
756 pdkim_strncat(cur_tag
,p
,1);
759 where
= PDKIM_HDR_VALUE
;
764 if (where
== PDKIM_HDR_VALUE
) {
766 cur_val
= pdkim_strnew(NULL
);
768 if ( (*p
== '\r') || (*p
== '\n') )
771 if ( (*p
== ';') || (*p
== '\0') ) {
772 if (cur_tag
->len
> 0) {
773 pdkim_strtrim(cur_val
);
775 if (ctx
->debug_stream
)
776 fprintf(ctx
->debug_stream
, "%s=%s\n", cur_tag
->str
, cur_val
->str
);
778 switch (cur_tag
->str
[0]) {
780 /* This tag isn't evaluated because:
781 - We only support version DKIM1.
782 - Which is the default for this value (set below)
783 - Other versions are currently not specified. */
786 pub
->hashes
= strdup(cur_val
->str
);
789 pub
->granularity
= strdup(cur_val
->str
);
792 pub
->notes
= pdkim_decode_qp(cur_val
->str
);
795 pub
->key
= pdkim_decode_base64(cur_val
->str
,&(pub
->key_len
));
798 pub
->hashes
= strdup(cur_val
->str
);
801 pub
->srvtype
= strdup(cur_val
->str
);
804 if (strchr(cur_val
->str
,'t') != NULL
) pub
->testing
= 1;
805 if (strchr(cur_val
->str
,'s') != NULL
) pub
->no_subdomaining
= 1;
809 if (ctx
->debug_stream
)
810 fprintf(ctx
->debug_stream
, "Unknown tag encountered\n");
815 pdkim_strclear(cur_tag
);
816 pdkim_strclear(cur_val
);
817 where
= PDKIM_HDR_LIMBO
;
820 else pdkim_strncat(cur_val
,p
,1);
824 if (*p
== '\0') break;
828 /* Set fallback defaults */
829 if (pub
->version
== NULL
) pub
->version
= strdup(PDKIM_PUB_RECORD_VERSION
);
830 if (pub
->granularity
== NULL
) pub
->granularity
= strdup("*");
831 if (pub
->keytype
== NULL
) pub
->keytype
= strdup("rsa");
832 if (pub
->srvtype
== NULL
) pub
->srvtype
= strdup("*");
835 if (pub
->key
== NULL
) {
836 pdkim_free_pubkey(pub
);
844 /* -------------------------------------------------------------------------- */
845 int pdkim_update_bodyhash(pdkim_ctx
*ctx
, char *data
, int len
) {
846 pdkim_signature
*sig
= ctx
->sig
;
847 /* Cache relaxed version of data */
848 char *relaxed_data
= NULL
;
851 /* Traverse all signatures, updating their hashes. */
852 while (sig
!= NULL
) {
853 /* Defaults to simple canon (no further treatment necessary) */
854 char *canon_data
= data
;
857 if (sig
->canon_body
== PDKIM_CANON_RELAXED
) {
858 /* Relax the line if not done already */
859 if (relaxed_data
== NULL
) {
863 relaxed_data
= malloc(len
+1);
864 if (relaxed_data
== NULL
) return PDKIM_ERR_OOM
;
867 if ( (c
== '\t') || (c
== ' ') ) {
868 c
= ' '; /* Turns WSP into SP */
876 relaxed_data
[q
++] = c
;
879 relaxed_data
[q
] = '\0';
882 canon_data
= relaxed_data
;
883 canon_len
= relaxed_len
;
886 /* Make sure we don't exceed the to-be-signed body length */
887 if ((sig
->bodylength
>= 0) &&
888 ((sig
->signed_body_bytes
+(unsigned long)canon_len
) > sig
->bodylength
))
889 canon_len
= (sig
->bodylength
- sig
->signed_body_bytes
);
892 if (sig
->algo
== PDKIM_ALGO_RSA_SHA1
)
893 sha1_update(sig
->sha1_body
,(unsigned char *)canon_data
,canon_len
);
895 sha2_update(sig
->sha2_body
,(unsigned char *)canon_data
,canon_len
);
896 sig
->signed_body_bytes
+= canon_len
;
898 if (ctx
->debug_stream
!=NULL
)
899 pdkim_quoteprint(ctx
->debug_stream
,canon_data
,canon_len
,0);
906 if (relaxed_data
!= NULL
) free(relaxed_data
);
911 /* -------------------------------------------------------------------------- */
912 int pdkim_finish_bodyhash(pdkim_ctx
*ctx
) {
913 pdkim_signature
*sig
= ctx
->sig
;
915 /* Traverse all signatures */
916 while (sig
!= NULL
) {
919 unsigned char bh
[32]; /* SHA-256 = 32 Bytes, SHA-1 = 20 Bytes */
920 if (sig
->algo
== PDKIM_ALGO_RSA_SHA1
)
921 sha1_finish(sig
->sha1_body
,bh
);
923 sha2_finish(sig
->sha2_body
,bh
);
926 if (ctx
->debug_stream
) {
927 fprintf(ctx
->debug_stream
, "PDKIM [%s] Body bytes hashed: %lu\n",
928 sig
->domain
, sig
->signed_body_bytes
);
929 fprintf(ctx
->debug_stream
, "PDKIM [%s] bh computed: ", sig
->domain
);
930 pdkim_hexprint(ctx
->debug_stream
, (char *)bh
,
931 (sig
->algo
== PDKIM_ALGO_RSA_SHA1
)?20:32,1);
935 /* SIGNING -------------------------------------------------------------- */
936 if (ctx
->mode
== PDKIM_MODE_SIGN
) {
937 sig
->bodyhash_len
= (sig
->algo
== PDKIM_ALGO_RSA_SHA1
)?20:32;
938 sig
->bodyhash
= malloc(sig
->bodyhash_len
);
939 if (sig
->bodyhash
== NULL
) return PDKIM_ERR_OOM
;
940 memcpy(sig
->bodyhash
,bh
,sig
->bodyhash_len
);
942 /* If bodylength limit is set, and we have received less bytes
943 than the requested amount, effectively remove the limit tag. */
944 if (sig
->signed_body_bytes
< sig
->bodylength
) sig
->bodylength
= -1;
946 /* VERIFICATION --------------------------------------------------------- */
948 /* Compare bodyhash */
949 if (memcmp(bh
,sig
->bodyhash
,
950 (sig
->algo
== PDKIM_ALGO_RSA_SHA1
)?20:32) == 0) {
952 if (ctx
->debug_stream
)
953 fprintf(ctx
->debug_stream
, "PDKIM [%s] Body hash verified OK\n",
959 if (ctx
->debug_stream
) {
960 fprintf(ctx
->debug_stream
, "PDKIM [%s] Body hash did NOT verify\n",
962 fprintf(ctx
->debug_stream
, "PDKIM [%s] bh signature: ", sig
->domain
);
963 pdkim_hexprint(ctx
->debug_stream
, sig
->bodyhash
,
964 (sig
->algo
== PDKIM_ALGO_RSA_SHA1
)?20:32,1);
967 sig
->verify_status
= PDKIM_VERIFY_FAIL
;
968 sig
->verify_ext_status
= PDKIM_VERIFY_FAIL_BODY
;
980 /* -------------------------------------------------------------------------- */
981 /* Callback from pdkim_feed below for processing complete body lines */
982 int pdkim_bodyline_complete(pdkim_ctx
*ctx
) {
983 char *p
= ctx
->linebuf
;
984 int n
= ctx
->linebuf_offset
;
986 /* Ignore extra data if we've seen the end-of-data marker */
987 if (ctx
->seen_eod
) goto BAIL
;
989 /* We've always got one extra byte to stuff a zero ... */
990 ctx
->linebuf
[(ctx
->linebuf_offset
)] = '\0';
992 if (ctx
->input_mode
== PDKIM_INPUT_SMTP
) {
993 /* Terminate on EOD marker */
994 if (memcmp(p
,".\r\n",3) == 0) {
999 if (memcmp(p
,"..",2) == 0) {
1005 /* Empty lines need to be buffered until we find a non-empty line */
1006 if (memcmp(p
,"\r\n",2) == 0) {
1007 ctx
->num_buffered_crlf
++;
1011 /* At this point, we have a non-empty line, so release the buffered ones. */
1012 while (ctx
->num_buffered_crlf
) {
1013 pdkim_update_bodyhash(ctx
,"\r\n",2);
1014 ctx
->num_buffered_crlf
--;
1017 pdkim_update_bodyhash(ctx
,p
,n
);
1020 ctx
->linebuf_offset
= 0;
1025 /* -------------------------------------------------------------------------- */
1026 /* Callback from pdkim_feed below for processing complete headers */
1027 #define DKIM_SIGNATURE_HEADERNAME "DKIM-Signature:"
1028 int pdkim_header_complete(pdkim_ctx
*ctx
) {
1029 pdkim_signature
*sig
= ctx
->sig
;
1031 /* Special case: The last header can have an extra \r appended */
1032 if ( (ctx
->cur_header
->len
> 1) &&
1033 (ctx
->cur_header
->str
[(ctx
->cur_header
->len
)-1] == '\r') ) {
1034 ctx
->cur_header
->str
[(ctx
->cur_header
->len
)-1] = '\0';
1035 ctx
->cur_header
->len
--;
1039 if (ctx
->num_headers
> PDKIM_MAX_HEADERS
) goto BAIL
;
1041 /* Traverse all signatures */
1042 while (sig
!= NULL
) {
1043 pdkim_stringlist
*list
;
1045 /* SIGNING -------------------------------------------------------------- */
1046 if (ctx
->mode
== PDKIM_MODE_SIGN
) {
1047 if (header_name_match(ctx
->cur_header
->str
,
1050 PDKIM_DEFAULT_SIGN_HEADERS
, 0) != PDKIM_OK
) goto NEXT_SIG
;
1052 /* VERIFICATION --------------------------------------------------------- */
1054 /* Header is not included or all instances were already 'ticked off' */
1055 if (header_name_match(ctx
->cur_header
->str
,
1056 sig
->hnames_check
, 1) != PDKIM_OK
) goto NEXT_SIG
;
1059 /* Add header to the signed headers list (in reverse order) */
1060 list
= pdkim_prepend_stringlist(sig
->headers
,
1061 ctx
->cur_header
->str
);
1062 if (list
== NULL
) return PDKIM_ERR_OOM
;
1063 sig
->headers
= list
;
1069 /* DKIM-Signature: headers are added to the verification list */
1070 if ( (ctx
->mode
== PDKIM_MODE_VERIFY
) &&
1071 (strncasecmp(ctx
->cur_header
->str
,
1072 DKIM_SIGNATURE_HEADERNAME
,
1073 strlen(DKIM_SIGNATURE_HEADERNAME
)) == 0) ) {
1074 pdkim_signature
*new_sig
;
1075 /* Create and chain new signature block */
1077 if (ctx
->debug_stream
)
1078 fprintf(ctx
->debug_stream
,
1079 "PDKIM >> Found sig, trying to parse >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
1081 new_sig
= pdkim_parse_sig_header(ctx
, ctx
->cur_header
->str
);
1082 if (new_sig
!= NULL
) {
1083 pdkim_signature
*last_sig
= ctx
->sig
;
1084 if (last_sig
== NULL
) {
1088 while (last_sig
->next
!= NULL
) { last_sig
= last_sig
->next
; };
1089 last_sig
->next
= new_sig
;
1094 if (ctx
->debug_stream
) {
1095 fprintf(ctx
->debug_stream
,"Error while parsing signature header\n");
1096 fprintf(ctx
->debug_stream
,
1097 "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
1104 pdkim_strclear(ctx
->cur_header
); /* Re-use existing pdkim_str */
1110 /* -------------------------------------------------------------------------- */
1111 #define HEADER_BUFFER_FRAG_SIZE 256
1112 DLLEXPORT
int pdkim_feed (pdkim_ctx
*ctx
,
1116 for (p
=0;p
<len
;p
++) {
1118 if (ctx
->past_headers
) {
1119 /* Processing body byte */
1120 ctx
->linebuf
[(ctx
->linebuf_offset
)++] = c
;
1122 int rc
= pdkim_bodyline_complete(ctx
); /* End of line */
1123 if (rc
!= PDKIM_OK
) return rc
;
1125 if (ctx
->linebuf_offset
== (PDKIM_MAX_BODY_LINE_LEN
-1))
1126 return PDKIM_ERR_LONG_LINE
;
1129 /* Processing header byte */
1133 int rc
= pdkim_header_complete(ctx
); /* Seen last header line */
1134 if (rc
!= PDKIM_OK
) return rc
;
1135 ctx
->past_headers
= 1;
1138 if (ctx
->debug_stream
)
1139 fprintf(ctx
->debug_stream
,
1140 "PDKIM >> Hashed body data, canonicalized >>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
1144 else ctx
->seen_lf
= 1;
1146 else if (ctx
->seen_lf
) {
1147 if (! ((c
== '\t') || (c
== ' '))) {
1148 int rc
= pdkim_header_complete(ctx
); /* End of header */
1149 if (rc
!= PDKIM_OK
) return rc
;
1154 if (ctx
->cur_header
== NULL
) {
1155 ctx
->cur_header
= pdkim_strnew(NULL
);
1156 if (ctx
->cur_header
== NULL
) return PDKIM_ERR_OOM
;
1158 if (ctx
->cur_header
->len
< PDKIM_MAX_HEADER_LEN
)
1159 if (pdkim_strncat(ctx
->cur_header
,&data
[p
],1) == NULL
)
1160 return PDKIM_ERR_OOM
;
1167 /* -------------------------------------------------------------------------- */
1168 char *pdkim_create_header(pdkim_signature
*sig
, int final
) {
1170 char *base64_bh
= NULL
;
1171 char *base64_b
= NULL
;
1172 pdkim_str
*hdr
= pdkim_strnew("DKIM-Signature: v="PDKIM_SIGNATURE_VERSION
);
1173 if (hdr
== NULL
) return NULL
;
1175 base64_bh
= pdkim_encode_base64(sig
->bodyhash
, sig
->bodyhash_len
);
1176 if (base64_bh
== NULL
) goto BAIL
;
1178 /* Required and static bits */
1180 pdkim_strcat(hdr
,"; a=") &&
1181 pdkim_strcat(hdr
,pdkim_algos
[sig
->algo
]) &&
1182 pdkim_strcat(hdr
,"; q=") &&
1183 pdkim_strcat(hdr
,pdkim_querymethods
[sig
->querymethod
]) &&
1184 pdkim_strcat(hdr
,"; c=") &&
1185 pdkim_strcat(hdr
,pdkim_canons
[sig
->canon_headers
]) &&
1186 pdkim_strcat(hdr
,"/") &&
1187 pdkim_strcat(hdr
,pdkim_canons
[sig
->canon_body
]) &&
1188 pdkim_strcat(hdr
,"; d=") &&
1189 pdkim_strcat(hdr
,sig
->domain
) &&
1190 pdkim_strcat(hdr
,"; s=") &&
1191 pdkim_strcat(hdr
,sig
->selector
) &&
1192 pdkim_strcat(hdr
,";\r\n\th=") &&
1193 pdkim_strcat(hdr
,sig
->headernames
) &&
1194 pdkim_strcat(hdr
,"; bh=") &&
1195 pdkim_strcat(hdr
,base64_bh
) &&
1196 pdkim_strcat(hdr
,";\r\n\t")
1199 if (sig
->identity
!= NULL
) {
1200 if (!( pdkim_strcat(hdr
,"i=") &&
1201 pdkim_strcat(hdr
,sig
->identity
) &&
1202 pdkim_strcat(hdr
,";") ) ) {
1206 if (sig
->created
> 0) {
1207 if (!( pdkim_strcat(hdr
,"t=") &&
1208 pdkim_numcat(hdr
,sig
->created
) &&
1209 pdkim_strcat(hdr
,";") ) ) {
1213 if (sig
->expires
> 0) {
1214 if (!( pdkim_strcat(hdr
,"x=") &&
1215 pdkim_numcat(hdr
,sig
->expires
) &&
1216 pdkim_strcat(hdr
,";") ) ) {
1220 if (sig
->bodylength
>= 0) {
1221 if (!( pdkim_strcat(hdr
,"l=") &&
1222 pdkim_numcat(hdr
,sig
->bodylength
) &&
1223 pdkim_strcat(hdr
,";") ) ) {
1227 /* Extra linebreak */
1228 if (hdr
->str
[(hdr
->len
)-1] == ';') {
1229 if (!pdkim_strcat(hdr
," \r\n\t")) goto BAIL
;
1231 /* Preliminary or final version? */
1233 base64_b
= pdkim_encode_base64(sig
->sigdata
, sig
->sigdata_len
);
1234 if (base64_b
== NULL
) goto BAIL
;
1236 pdkim_strcat(hdr
,"b=") &&
1237 pdkim_strcat(hdr
,base64_b
) &&
1238 pdkim_strcat(hdr
,";")
1242 if (pdkim_strcat(hdr
,"b=;")) goto DONE
;
1249 rc
= strdup(hdr
->str
);
1253 if (base64_bh
!= NULL
) free(base64_bh
);
1254 if (base64_b
!= NULL
) free(base64_b
);
1259 /* -------------------------------------------------------------------------- */
1260 DLLEXPORT
int pdkim_feed_finish(pdkim_ctx
*ctx
, pdkim_signature
**return_signatures
) {
1261 pdkim_signature
*sig
= ctx
->sig
;
1262 pdkim_str
*headernames
= NULL
; /* Collected signed header names */
1264 /* Check if we must still flush a (partial) header. If that is the
1265 case, the message has no body, and we must compute a body hash
1266 out of '<CR><LF>' */
1267 if (ctx
->cur_header
->len
) {
1268 int rc
= pdkim_header_complete(ctx
);
1269 if (rc
!= PDKIM_OK
) return rc
;
1270 pdkim_update_bodyhash(ctx
,"\r\n",2);
1273 /* For non-smtp input, check if there's an unfinished line in the
1274 body line buffer. If that is the case, we must add a CRLF to the
1275 hash to properly terminate the message. */
1276 if ((ctx
->input_mode
== PDKIM_INPUT_NORMAL
) && ctx
->linebuf_offset
) {
1277 pdkim_update_bodyhash(ctx
, ctx
->linebuf
, ctx
->linebuf_offset
);
1278 pdkim_update_bodyhash(ctx
,"\r\n",2);
1281 if (ctx
->debug_stream
)
1282 fprintf(ctx
->debug_stream
,
1283 "\nPDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
1287 /* Build (and/or evaluate) body hash */
1288 if (pdkim_finish_bodyhash(ctx
) != PDKIM_OK
) return PDKIM_ERR_OOM
;
1290 /* SIGNING -------------------------------------------------------------- */
1291 if (ctx
->mode
== PDKIM_MODE_SIGN
) {
1292 headernames
= pdkim_strnew(NULL
);
1293 if (headernames
== NULL
) return PDKIM_ERR_OOM
;
1295 /* ---------------------------------------------------------------------- */
1297 while (sig
!= NULL
) {
1298 sha1_context sha1_headers
;
1299 sha2_context sha2_headers
;
1301 char headerhash
[32];
1303 if (sig
->algo
== PDKIM_ALGO_RSA_SHA1
)
1304 sha1_starts(&sha1_headers
);
1306 sha2_starts(&sha2_headers
,0);
1309 if (ctx
->debug_stream
)
1310 fprintf(ctx
->debug_stream
,
1311 "PDKIM >> Hashed header data, canonicalized, in sequence >>>>>>>>>>>>>>\n");
1314 /* SIGNING ---------------------------------------------------------------- */
1315 /* When signing, walk through our header list and add them to the hash. As we
1316 go, construct a list of the header's names to use for the h= parameter. */
1317 if (ctx
->mode
== PDKIM_MODE_SIGN
) {
1318 pdkim_stringlist
*p
= sig
->headers
;
1321 /* Collect header names (Note: colon presence is guaranteed here) */
1322 char *q
= strchr(p
->value
,':');
1323 if (pdkim_strncat(headernames
, p
->value
,
1324 (q
-(p
->value
))+((p
->next
==NULL
)?0:1)) == NULL
)
1325 return PDKIM_ERR_OOM
;
1327 if (sig
->canon_headers
== PDKIM_CANON_RELAXED
)
1328 rh
= pdkim_relax_header(p
->value
,1); /* cook header for relaxed canon */
1330 rh
= strdup(p
->value
); /* just copy it for simple canon */
1332 if (rh
== NULL
) return PDKIM_ERR_OOM
;
1334 /* Feed header to the hash algorithm */
1335 if (sig
->algo
== PDKIM_ALGO_RSA_SHA1
)
1336 sha1_update(&(sha1_headers
),(unsigned char *)rh
,strlen(rh
));
1338 sha2_update(&(sha2_headers
),(unsigned char *)rh
,strlen(rh
));
1340 if (ctx
->debug_stream
)
1341 pdkim_quoteprint(ctx
->debug_stream
, rh
, strlen(rh
), 1);
1347 /* VERIFICATION ----------------------------------------------------------- */
1348 /* When verifying, walk through the header name list in the h= parameter and
1349 add the headers to the hash in that order. */
1351 char *b
= strdup(sig
->headernames
);
1354 if (b
== NULL
) return PDKIM_ERR_OOM
;
1357 pdkim_stringlist
*hdrs
= sig
->headers
;
1359 if (q
!= NULL
) *q
= '\0';
1360 while (hdrs
!= NULL
) {
1361 if ( (strncasecmp(hdrs
->value
,p
,strlen(p
)) == 0) &&
1362 ((hdrs
->value
)[strlen(p
)] == ':') ) {
1364 if (sig
->canon_headers
== PDKIM_CANON_RELAXED
)
1365 rh
= pdkim_relax_header(hdrs
->value
,1); /* cook header for relaxed canon */
1367 rh
= strdup(hdrs
->value
); /* just copy it for simple canon */
1368 if (rh
== NULL
) return PDKIM_ERR_OOM
;
1369 /* Feed header to the hash algorithm */
1370 if (sig
->algo
== PDKIM_ALGO_RSA_SHA1
)
1371 sha1_update(&(sha1_headers
),(unsigned char *)rh
,strlen(rh
));
1373 sha2_update(&(sha2_headers
),(unsigned char *)rh
,strlen(rh
));
1375 if (ctx
->debug_stream
)
1376 pdkim_quoteprint(ctx
->debug_stream
, rh
, strlen(rh
), 1);
1379 (hdrs
->value
)[0] = '_';
1384 if (q
== NULL
) break;
1391 if (ctx
->debug_stream
)
1392 fprintf(ctx
->debug_stream
,
1393 "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
1396 /* SIGNING ---------------------------------------------------------------- */
1397 if (ctx
->mode
== PDKIM_MODE_SIGN
) {
1398 /* Copy headernames to signature struct */
1399 sig
->headernames
= strdup(headernames
->str
);
1400 pdkim_strfree(headernames
);
1402 /* Create signature header with b= omitted */
1403 sig_hdr
= pdkim_create_header(ctx
->sig
,0);
1405 /* VERIFICATION ----------------------------------------------------------- */
1407 sig_hdr
= strdup(sig
->rawsig_no_b_val
);
1409 /* ------------------------------------------------------------------------ */
1411 if (sig_hdr
== NULL
) return PDKIM_ERR_OOM
;
1413 /* Relax header if necessary */
1414 if (sig
->canon_headers
== PDKIM_CANON_RELAXED
) {
1415 char *relaxed_hdr
= pdkim_relax_header(sig_hdr
,0);
1417 if (relaxed_hdr
== NULL
) return PDKIM_ERR_OOM
;
1418 sig_hdr
= relaxed_hdr
;
1422 if (ctx
->debug_stream
) {
1423 fprintf(ctx
->debug_stream
,
1424 "PDKIM >> Signed DKIM-Signature header, canonicalized >>>>>>>>>>>>>>>>>\n");
1425 pdkim_quoteprint(ctx
->debug_stream
, sig_hdr
, strlen(sig_hdr
), 1);
1426 fprintf(ctx
->debug_stream
,
1427 "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
1431 /* Finalize header hash */
1432 if (sig
->algo
== PDKIM_ALGO_RSA_SHA1
) {
1433 sha1_update(&(sha1_headers
),(unsigned char *)sig_hdr
,strlen(sig_hdr
));
1434 sha1_finish(&(sha1_headers
),(unsigned char *)headerhash
);
1436 if (ctx
->debug_stream
) {
1437 fprintf(ctx
->debug_stream
, "PDKIM [%s] hh computed: ", sig
->domain
);
1438 pdkim_hexprint(ctx
->debug_stream
, headerhash
, 20, 1);
1443 sha2_update(&(sha2_headers
),(unsigned char *)sig_hdr
,strlen(sig_hdr
));
1444 sha2_finish(&(sha2_headers
),(unsigned char *)headerhash
);
1446 if (ctx
->debug_stream
) {
1447 fprintf(ctx
->debug_stream
, "PDKIM [%s] hh computed: ", sig
->domain
);
1448 pdkim_hexprint(ctx
->debug_stream
, headerhash
, 32, 1);
1455 /* SIGNING ---------------------------------------------------------------- */
1456 if (ctx
->mode
== PDKIM_MODE_SIGN
) {
1459 rsa_init(&rsa
,RSA_PKCS_V15
,0,NULL
,NULL
);
1461 /* Perform private key operation */
1462 if (rsa_parse_key(&rsa
, (unsigned char *)sig
->rsa_privkey
,
1463 strlen(sig
->rsa_privkey
), NULL
, 0) != 0) {
1464 return PDKIM_ERR_RSA_PRIVKEY
;
1467 sig
->sigdata_len
= mpi_size(&(rsa
.N
));
1468 sig
->sigdata
= malloc(sig
->sigdata_len
);
1469 if (sig
->sigdata
== NULL
) return PDKIM_ERR_OOM
;
1471 if (rsa_pkcs1_sign( &rsa
, RSA_PRIVATE
,
1472 ((sig
->algo
== PDKIM_ALGO_RSA_SHA1
)?
1473 RSA_SHA1
:RSA_SHA256
),
1475 (unsigned char *)headerhash
,
1476 (unsigned char *)sig
->sigdata
) != 0) {
1477 return PDKIM_ERR_RSA_SIGNING
;
1483 if (ctx
->debug_stream
) {
1484 fprintf(ctx
->debug_stream
, "PDKIM [%s] b computed: ",
1486 pdkim_hexprint(ctx
->debug_stream
, sig
->sigdata
, sig
->sigdata_len
, 1);
1490 sig
->signature_header
= pdkim_create_header(ctx
->sig
,1);
1491 if (sig
->signature_header
== NULL
) return PDKIM_ERR_OOM
;
1493 /* VERIFICATION ----------------------------------------------------------- */
1496 char *dns_txt_name
, *dns_txt_reply
;
1498 rsa_init(&rsa
,RSA_PKCS_V15
,0,NULL
,NULL
);
1500 dns_txt_name
= malloc(PDKIM_DNS_TXT_MAX_NAMELEN
);
1501 if (dns_txt_name
== NULL
) return PDKIM_ERR_OOM
;
1502 dns_txt_reply
= malloc(PDKIM_DNS_TXT_MAX_RECLEN
);
1503 if (dns_txt_reply
== NULL
) {
1505 return PDKIM_ERR_OOM
;
1507 memset(dns_txt_reply
,0,PDKIM_DNS_TXT_MAX_RECLEN
);
1508 memset(dns_txt_name
,0,PDKIM_DNS_TXT_MAX_NAMELEN
);
1510 if (snprintf(dns_txt_name
,PDKIM_DNS_TXT_MAX_NAMELEN
,
1511 "%s._domainkey.%s.",
1512 sig
->selector
,sig
->domain
) >= PDKIM_DNS_TXT_MAX_NAMELEN
) {
1513 sig
->verify_status
= PDKIM_VERIFY_INVALID
;
1514 sig
->verify_ext_status
= PDKIM_VERIFY_INVALID_BUFFER_SIZE
;
1518 if ((ctx
->dns_txt_callback(dns_txt_name
, dns_txt_reply
) != PDKIM_OK
) ||
1519 (dns_txt_reply
[0] == '\0')) {
1520 sig
->verify_status
= PDKIM_VERIFY_INVALID
;
1521 sig
->verify_ext_status
= PDKIM_VERIFY_INVALID_PUBKEY_UNAVAILABLE
;
1526 if (ctx
->debug_stream
) {
1527 fprintf(ctx
->debug_stream
,
1528 "PDKIM >> Parsing public key record >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
1529 fprintf(ctx
->debug_stream
,"Raw record: ");
1530 pdkim_quoteprint(ctx
->debug_stream
, dns_txt_reply
, strlen(dns_txt_reply
), 1);
1534 sig
->pubkey
= pdkim_parse_pubkey_record(ctx
,dns_txt_reply
);
1535 if (sig
->pubkey
== NULL
) {
1536 sig
->verify_status
= PDKIM_VERIFY_INVALID
;
1537 sig
->verify_ext_status
= PDKIM_VERIFY_INVALID_PUBKEY_PARSING
;
1539 if (ctx
->debug_stream
) {
1540 fprintf(ctx
->debug_stream
,"Error while parsing public key record\n");
1541 fprintf(ctx
->debug_stream
,
1542 "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
1549 if (ctx
->debug_stream
) {
1550 fprintf(ctx
->debug_stream
,
1551 "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
1555 if (rsa_parse_public_key(&rsa
,
1556 (unsigned char *)sig
->pubkey
->key
,
1557 sig
->pubkey
->key_len
) != 0) {
1558 sig
->verify_status
= PDKIM_VERIFY_INVALID
;
1559 sig
->verify_ext_status
= PDKIM_VERIFY_INVALID_PUBKEY_PARSING
;
1563 /* Check the signature */
1564 if (rsa_pkcs1_verify(&rsa
,
1566 ((sig
->algo
== PDKIM_ALGO_RSA_SHA1
)?
1567 RSA_SHA1
:RSA_SHA256
),
1569 (unsigned char *)headerhash
,
1570 (unsigned char *)sig
->sigdata
) != 0) {
1571 sig
->verify_status
= PDKIM_VERIFY_FAIL
;
1572 sig
->verify_ext_status
= PDKIM_VERIFY_FAIL_MESSAGE
;
1574 if (ctx
->debug_stream
) {
1575 fprintf(ctx
->debug_stream
, "PDKIM [%s] signature did NOT verify OK\n",
1582 /* We have a winner! */
1583 sig
->verify_status
= PDKIM_VERIFY_PASS
;
1586 if (ctx
->debug_stream
) {
1587 fprintf(ctx
->debug_stream
, "PDKIM [%s] signature verified OK\n",
1595 free(dns_txt_reply
);
1601 /* If requested, set return pointer to signature(s) */
1602 if (return_signatures
!= NULL
) {
1603 *return_signatures
= ctx
->sig
;
1610 /* -------------------------------------------------------------------------- */
1611 DLLEXPORT pdkim_ctx
*pdkim_init_verify(int input_mode
,
1612 int(*dns_txt_callback
)(char *, char *)
1614 pdkim_ctx
*ctx
= malloc(sizeof(pdkim_ctx
));
1615 if (ctx
== NULL
) return NULL
;
1616 memset(ctx
,0,sizeof(pdkim_ctx
));
1618 ctx
->linebuf
= malloc(PDKIM_MAX_BODY_LINE_LEN
);
1619 if (ctx
->linebuf
== NULL
) {
1624 ctx
->mode
= PDKIM_MODE_VERIFY
;
1625 ctx
->input_mode
= input_mode
;
1626 ctx
->dns_txt_callback
= dns_txt_callback
;
1632 /* -------------------------------------------------------------------------- */
1633 DLLEXPORT pdkim_ctx
*pdkim_init_sign(int input_mode
,
1636 char *rsa_privkey
) {
1638 pdkim_signature
*sig
;
1640 if (!domain
|| !selector
|| !rsa_privkey
) return NULL
;
1642 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 sig
= malloc(sizeof(pdkim_signature
));
1658 memset(sig
,0,sizeof(pdkim_signature
));
1659 sig
->bodylength
= -1;
1661 ctx
->mode
= PDKIM_MODE_SIGN
;
1662 ctx
->input_mode
= input_mode
;
1665 ctx
->sig
->domain
= strdup(domain
);
1666 ctx
->sig
->selector
= strdup(selector
);
1667 ctx
->sig
->rsa_privkey
= strdup(rsa_privkey
);
1669 if (!ctx
->sig
->domain
|| !ctx
->sig
->selector
|| !ctx
->sig
->rsa_privkey
) {
1670 pdkim_free_ctx(ctx
);
1674 ctx
->sig
->sha1_body
= malloc(sizeof(sha1_context
));
1675 if (ctx
->sig
->sha1_body
== NULL
) {
1676 pdkim_free_ctx(ctx
);
1679 sha1_starts(ctx
->sig
->sha1_body
);
1681 ctx
->sig
->sha2_body
= malloc(sizeof(sha2_context
));
1682 if (ctx
->sig
->sha2_body
== NULL
) {
1683 pdkim_free_ctx(ctx
);
1686 sha2_starts(ctx
->sig
->sha2_body
,0);
1692 /* -------------------------------------------------------------------------- */
1693 DLLEXPORT
void pdkim_set_debug_stream(pdkim_ctx
*ctx
,
1694 FILE *debug_stream
) {
1695 ctx
->debug_stream
= debug_stream
;
1699 /* -------------------------------------------------------------------------- */
1700 DLLEXPORT
int pdkim_set_optional(pdkim_ctx
*ctx
,
1707 unsigned long created
,
1708 unsigned long expires
) {
1710 if (identity
!= NULL
) {
1711 ctx
->sig
->identity
= strdup(identity
);
1712 if (ctx
->sig
->identity
== NULL
) return PDKIM_ERR_OOM
;
1715 if (sign_headers
!= NULL
) {
1716 ctx
->sig
->sign_headers
= strdup(sign_headers
);
1717 if (ctx
->sig
->sign_headers
== NULL
) return PDKIM_ERR_OOM
;
1720 ctx
->sig
->canon_headers
= canon_headers
;
1721 ctx
->sig
->canon_body
= canon_body
;
1722 ctx
->sig
->bodylength
= bodylength
;
1723 ctx
->sig
->algo
= algo
;
1724 ctx
->sig
->created
= created
;
1725 ctx
->sig
->expires
= expires
;