2 * PDKIM - a RFC4871 (DKIM) implementation
4 * Copyright (C) 2009 - 2016 Tom Kistner <tom@duncanthrax.net>
5 * Copyright (C) 2016 Jeremy Harris <jgh@exim.org>
7 * http://duncanthrax.net/pdkim/
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License along
20 * with this program; if not, write to the Free Software Foundation, Inc.,
21 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
27 #ifndef DISABLE_DKIM /* entire file */
30 # error Need SUPPORT_TLS for DKIM
33 #include "crypt_ver.h"
36 # include <openssl/rsa.h>
37 # include <openssl/ssl.h>
38 # include <openssl/err.h>
39 #elif defined(RSA_GNUTLS)
40 # include <gnutls/gnutls.h>
41 # include <gnutls/x509.h>
42 # include <gnutls/abstract.h>
46 # include <gnutls/crypto.h>
47 #elif defined(SHA_POLARSSL)
48 # include "polarssl/sha1.h"
49 # include "polarssl/sha2.h"
54 #define PDKIM_SIGNATURE_VERSION "1"
55 #define PDKIM_PUB_RECORD_VERSION "DKIM1"
57 #define PDKIM_MAX_HEADER_LEN 65536
58 #define PDKIM_MAX_HEADERS 512
59 #define PDKIM_MAX_BODY_LINE_LEN 16384
60 #define PDKIM_DNS_TXT_MAX_NAMELEN 1024
61 #define PDKIM_DEFAULT_SIGN_HEADERS "From:Sender:Reply-To:Subject:Date:"\
62 "Message-ID:To:Cc:MIME-Version:Content-Type:"\
63 "Content-Transfer-Encoding:Content-ID:"\
64 "Content-Description:Resent-Date:Resent-From:"\
65 "Resent-Sender:Resent-To:Resent-Cc:"\
66 "Resent-Message-ID:In-Reply-To:References:"\
67 "List-Id:List-Help:List-Unsubscribe:"\
68 "List-Subscribe:List-Post:List-Owner:List-Archive"
70 /* -------------------------------------------------------------------------- */
71 struct pdkim_stringlist
{
77 #define PDKIM_STR_ALLOC_FRAG 256
81 unsigned int allocated
;
84 /* -------------------------------------------------------------------------- */
85 /* A bunch of list constants */
86 const char *pdkim_querymethods
[] = {
90 const char *pdkim_algos
[] = {
95 const char *pdkim_canons
[] = {
100 const char *pdkim_hashes
[] = {
105 const char *pdkim_keytypes
[] = {
110 typedef struct pdkim_combined_canon_entry
{
114 } pdkim_combined_canon_entry
;
116 pdkim_combined_canon_entry pdkim_combined_canons
[] = {
117 { "simple/simple", PDKIM_CANON_SIMPLE
, PDKIM_CANON_SIMPLE
},
118 { "simple/relaxed", PDKIM_CANON_SIMPLE
, PDKIM_CANON_RELAXED
},
119 { "relaxed/simple", PDKIM_CANON_RELAXED
, PDKIM_CANON_SIMPLE
},
120 { "relaxed/relaxed", PDKIM_CANON_RELAXED
, PDKIM_CANON_RELAXED
},
121 { "simple", PDKIM_CANON_SIMPLE
, PDKIM_CANON_SIMPLE
},
122 { "relaxed", PDKIM_CANON_RELAXED
, PDKIM_CANON_SIMPLE
},
127 /* -------------------------------------------------------------------------- */
130 pdkim_verify_status_str(int status
)
133 case PDKIM_VERIFY_NONE
: return "PDKIM_VERIFY_NONE";
134 case PDKIM_VERIFY_INVALID
: return "PDKIM_VERIFY_INVALID";
135 case PDKIM_VERIFY_FAIL
: return "PDKIM_VERIFY_FAIL";
136 case PDKIM_VERIFY_PASS
: return "PDKIM_VERIFY_PASS";
137 default: return "PDKIM_VERIFY_UNKNOWN";
142 pdkim_verify_ext_status_str(int ext_status
)
145 case PDKIM_VERIFY_FAIL_BODY
: return "PDKIM_VERIFY_FAIL_BODY";
146 case PDKIM_VERIFY_FAIL_MESSAGE
: return "PDKIM_VERIFY_FAIL_MESSAGE";
147 case PDKIM_VERIFY_INVALID_PUBKEY_UNAVAILABLE
: return "PDKIM_VERIFY_INVALID_PUBKEY_UNAVAILABLE";
148 case PDKIM_VERIFY_INVALID_BUFFER_SIZE
: return "PDKIM_VERIFY_INVALID_BUFFER_SIZE";
149 case PDKIM_VERIFY_INVALID_PUBKEY_DNSRECORD
: return "PDKIM_VERIFY_INVALID_PUBKEY_DNSRECORD";
150 case PDKIM_VERIFY_INVALID_PUBKEY_IMPORT
: return "PDKIM_VERIFY_INVALID_PUBKEY_IMPORT";
151 default: return "PDKIM_VERIFY_UNKNOWN";
156 /* -------------------------------------------------------------------------- */
157 /* Print debugging functions */
159 pdkim_quoteprint(const char *data
, int len
, int lf
)
162 const unsigned char *p
= (const unsigned char *)data
;
164 for (i
= 0; i
< len
; i
++)
169 case ' ' : debug_printf("{SP}"); break;
170 case '\t': debug_printf("{TB}"); break;
171 case '\r': debug_printf("{CR}"); break;
172 case '\n': debug_printf("{LF}"); break;
173 case '{' : debug_printf("{BO}"); break;
174 case '}' : debug_printf("{BC}"); break;
176 if ( (c
< 32) || (c
> 127) )
177 debug_printf("{%02x}", c
);
179 debug_printf("%c", c
);
188 pdkim_hexprint(const char *data
, int len
, int lf
)
191 const unsigned char *p
= (const unsigned char *)data
;
193 for (i
= 0 ; i
< len
; i
++)
194 debug_printf("%02x", p
[i
]);
201 /* String package: should be replaced by Exim standard ones */
203 static pdkim_stringlist
*
204 pdkim_prepend_stringlist(pdkim_stringlist
*base
, char *str
)
206 pdkim_stringlist
*new_entry
= malloc(sizeof(pdkim_stringlist
));
208 if (!new_entry
) return NULL
;
209 memset(new_entry
, 0, sizeof(pdkim_stringlist
));
210 if (!(new_entry
->value
= strdup(str
))) return NULL
;
213 pdkim_stringlist
*last
= base
;
214 while (last
->next
!= NULL
) { last
= last
->next
; }
215 last
->next
= new_entry
;
223 /* -------------------------------------------------------------------------- */
224 /* A small "growing string" implementation to escape malloc/realloc hell */
227 pdkim_strnew (const char *cstr
)
229 unsigned int len
= cstr
? strlen(cstr
) : 0;
230 pdkim_str
*p
= malloc(sizeof(pdkim_str
));
233 memset(p
, 0, sizeof(pdkim_str
));
234 if (!(p
->str
= malloc(len
+1)))
239 p
->allocated
= len
+1;
242 strcpy(p
->str
, cstr
);
244 p
->str
[p
->len
] = '\0';
249 pdkim_strncat(pdkim_str
*str
, const char *data
, int len
)
251 if ((str
->allocated
- str
->len
) < (len
+1))
253 /* Extend the buffer */
254 int num_frags
= ((len
+1)/PDKIM_STR_ALLOC_FRAG
)+1;
255 char *n
= realloc(str
->str
,
256 (str
->allocated
+(num_frags
*PDKIM_STR_ALLOC_FRAG
)));
257 if (n
== NULL
) return NULL
;
259 str
->allocated
+= (num_frags
*PDKIM_STR_ALLOC_FRAG
);
261 strncpy(&(str
->str
[str
->len
]), data
, len
);
263 str
->str
[str
->len
] = '\0';
268 pdkim_strcat(pdkim_str
*str
, const char *cstr
)
270 return pdkim_strncat(str
, cstr
, strlen(cstr
));
274 pdkim_strtrim(pdkim_str
*str
)
278 while ( (*p
!= '\0') && ((*p
== '\t') || (*p
== ' ')) ) p
++;
279 while (*p
!= '\0') {*q
= *p
; q
++; p
++;}
281 while ( (q
!= str
->str
) && ( (*q
== '\0') || (*q
== '\t') || (*q
== ' ') ) )
286 str
->len
= strlen(str
->str
);
291 pdkim_strclear(pdkim_str
*str
)
299 pdkim_strfree(pdkim_str
*str
)
302 if (str
->str
) free(str
->str
);
308 /* -------------------------------------------------------------------------- */
311 pdkim_free_pubkey(pdkim_pubkey
*pub
)
315 if (pub
->version
) free(pub
->version
);
316 if (pub
->granularity
) free(pub
->granularity
);
317 if (pub
->hashes
) free(pub
->hashes
);
318 if (pub
->keytype
) free(pub
->keytype
);
319 if (pub
->srvtype
) free(pub
->srvtype
);
320 if (pub
->notes
) free(pub
->notes
);
321 /* if (pub->key ) free(pub->key); */
327 /* -------------------------------------------------------------------------- */
330 pdkim_free_sig(pdkim_signature
*sig
)
334 pdkim_signature
*next
= (pdkim_signature
*)sig
->next
;
336 pdkim_stringlist
*e
= sig
->headers
;
339 pdkim_stringlist
*c
= e
;
340 if (e
->value
) free(e
->value
);
345 if (sig
->selector
) free(sig
->selector
);
346 if (sig
->domain
) free(sig
->domain
);
347 if (sig
->identity
) free(sig
->identity
);
348 if (sig
->headernames
) free(sig
->headernames
);
349 if (sig
->copiedheaders
) free(sig
->copiedheaders
);
350 if (sig
->rsa_privkey
) free(sig
->rsa_privkey
);
351 if (sig
->sign_headers
) free(sig
->sign_headers
);
352 if (sig
->signature_header
) free(sig
->signature_header
);
354 if (sig
->pubkey
) pdkim_free_pubkey(sig
->pubkey
);
357 if (next
) pdkim_free_sig(next
);
362 /* -------------------------------------------------------------------------- */
365 pdkim_free_ctx(pdkim_ctx
*ctx
)
369 pdkim_stringlist
*e
= ctx
->headers
;
372 pdkim_stringlist
*c
= e
;
373 if (e
->value
) free(e
->value
);
377 pdkim_free_sig(ctx
->sig
);
378 pdkim_strfree(ctx
->cur_header
);
384 /* -------------------------------------------------------------------------- */
385 /* Matches the name of the passed raw "header" against
386 the passed colon-separated "list", starting at entry
387 "start". Returns the position of the header name in
391 header_name_match(const char *header
,
401 /* Get header name */
402 char *hcolon
= strchr(header
, ':');
404 if (!hcolon
) return rc
; /* This isn't a header */
406 if (!(hname
= malloc((hcolon
-header
)+1)))
407 return PDKIM_ERR_OOM
;
408 memset(hname
, 0, (hcolon
-header
)+1);
409 strncpy(hname
, header
, (hcolon
-header
));
411 /* Copy tick-off list locally, so we can punch zeroes into it */
412 if (!(lcopy
= strdup(tick
)))
415 return PDKIM_ERR_OOM
;
423 if (strcasecmp(p
, hname
) == 0)
426 /* Invalidate header name instance in tick-off list */
427 if (do_tick
) tick
[p
-lcopy
] = '_';
435 if (strcasecmp(p
, hname
) == 0)
438 /* Invalidate header name instance in tick-off list */
439 if (do_tick
) tick
[p
-lcopy
] = '_';
449 /* -------------------------------------------------------------------------- */
450 /* Performs "relaxed" canonicalization of a header. The returned pointer needs
454 pdkim_relax_header (char *header
, int crlf
)
456 BOOL past_field_name
= FALSE
;
457 BOOL seen_wsp
= FALSE
;
460 char *relaxed
= malloc(strlen(header
)+3);
462 if (!relaxed
) return NULL
;
465 for (p
= header
; *p
!= '\0'; p
++)
469 if (c
== '\r' || c
== '\n')
471 if (c
== '\t' || c
== ' ')
475 c
= ' '; /* Turns WSP into SP */
479 if (!past_field_name
&& c
== ':')
481 if (seen_wsp
) q
--; /* This removes WSP before the colon */
482 seen_wsp
= TRUE
; /* This removes WSP after the colon */
483 past_field_name
= TRUE
;
488 /* Lowercase header name */
489 if (!past_field_name
) c
= tolower(c
);
493 if (q
> relaxed
&& q
[-1] == ' ') q
--; /* Squash eventual trailing SP */
496 if (crlf
) strcat(relaxed
, "\r\n");
501 /* -------------------------------------------------------------------------- */
502 #define PDKIM_QP_ERROR_DECODE -1
505 pdkim_decode_qp_char(char *qp_p
, int *c
)
507 char *initial_pos
= qp_p
;
509 /* Advance one char */
512 /* Check for two hex digits and decode them */
513 if (isxdigit(*qp_p
) && isxdigit(qp_p
[1]))
515 /* Do hex conversion */
516 *c
= (isdigit(*qp_p
) ? *qp_p
- '0' : toupper(*qp_p
) - 'A' + 10) << 4;
517 *c
|= isdigit(qp_p
[1]) ? qp_p
[1] - '0' : toupper(qp_p
[1]) - 'A' + 10;
521 /* Illegal char here */
522 *c
= PDKIM_QP_ERROR_DECODE
;
527 /* -------------------------------------------------------------------------- */
530 pdkim_decode_qp(char *str
)
535 char *n
= malloc(strlen(p
)+1);
545 p
= pdkim_decode_qp_char(p
, &nchar
);
561 /* -------------------------------------------------------------------------- */
564 pdkim_decode_base64(char *str
, int *num_decoded
)
568 int old_pool
= store_pool
;
570 /* There is a store-reset between header & body reception
571 so cannot use the main pool */
573 store_pool
= POOL_PERM
;
574 dlen
= b64decode(US str
, USS
&res
);
575 store_pool
= old_pool
;
577 if (dlen
< 0) return NULL
;
579 if (num_decoded
) *num_decoded
= dlen
;
584 /* -------------------------------------------------------------------------- */
587 pdkim_encode_base64(char *str
, int num
)
590 int old_pool
= store_pool
;
592 store_pool
= POOL_PERM
;
593 ret
= CS
b64encode(US str
, num
);
594 store_pool
= old_pool
;
599 /* -------------------------------------------------------------------------- */
600 #define PDKIM_HDR_LIMBO 0
601 #define PDKIM_HDR_TAG 1
602 #define PDKIM_HDR_VALUE 2
604 static pdkim_signature
*
605 pdkim_parse_sig_header(pdkim_ctx
*ctx
, char *raw_hdr
)
607 pdkim_signature
*sig
;
609 pdkim_str
*cur_tag
= NULL
;
610 pdkim_str
*cur_val
= NULL
;
611 BOOL past_hname
= FALSE
;
612 BOOL in_b_val
= FALSE
;
613 int where
= PDKIM_HDR_LIMBO
;
616 if (!(sig
= malloc(sizeof(pdkim_signature
)))) return NULL
;
617 memset(sig
, 0, sizeof(pdkim_signature
));
618 sig
->bodylength
= -1;
620 if (!(sig
->rawsig_no_b_val
= malloc(strlen(raw_hdr
)+1)))
626 q
= sig
->rawsig_no_b_val
;
628 for (p
= raw_hdr
; ; p
++)
633 if (c
== '\r' || c
== '\n')
636 /* Fast-forward through header name */
639 if (c
== ':') past_hname
= TRUE
;
643 if (where
== PDKIM_HDR_LIMBO
)
645 /* In limbo, just wait for a tag-char to appear */
646 if (!(c
>= 'a' && c
<= 'z'))
649 where
= PDKIM_HDR_TAG
;
652 if (where
== PDKIM_HDR_TAG
)
655 cur_tag
= pdkim_strnew(NULL
);
657 if (c
>= 'a' && c
<= 'z')
658 pdkim_strncat(cur_tag
, p
, 1);
662 if (strcmp(cur_tag
->str
, "b") == 0)
667 where
= PDKIM_HDR_VALUE
;
672 if (where
== PDKIM_HDR_VALUE
)
675 cur_val
= pdkim_strnew(NULL
);
677 if (c
== '\r' || c
== '\n' || c
== ' ' || c
== '\t')
680 if (c
== ';' || c
== '\0')
682 if (cur_tag
->len
> 0)
684 pdkim_strtrim(cur_val
);
686 DEBUG(D_acl
) debug_printf(" %s=%s\n", cur_tag
->str
, cur_val
->str
);
688 switch (cur_tag
->str
[0])
691 if (cur_tag
->str
[1] == 'h')
692 sig
->bodyhash
= pdkim_decode_base64(cur_val
->str
,
695 sig
->sigdata
= pdkim_decode_base64(cur_val
->str
,
699 /* We only support version 1, and that is currently the
700 only version there is. */
701 if (strcmp(cur_val
->str
, PDKIM_SIGNATURE_VERSION
) == 0)
705 for (i
= 0; pdkim_algos
[i
]; i
++)
706 if (strcmp(cur_val
->str
, pdkim_algos
[i
]) == 0)
713 for (i
= 0; pdkim_combined_canons
[i
].str
; i
++)
714 if (strcmp(cur_val
->str
, pdkim_combined_canons
[i
].str
) == 0)
716 sig
->canon_headers
= pdkim_combined_canons
[i
].canon_headers
;
717 sig
->canon_body
= pdkim_combined_canons
[i
].canon_body
;
722 for (i
= 0; pdkim_querymethods
[i
]; i
++)
723 if (strcmp(cur_val
->str
, pdkim_querymethods
[i
]) == 0)
725 sig
->querymethod
= i
;
730 sig
->selector
= strdup(cur_val
->str
); break;
732 sig
->domain
= strdup(cur_val
->str
); break;
734 sig
->identity
= pdkim_decode_qp(cur_val
->str
); break;
736 sig
->created
= strtoul(cur_val
->str
, NULL
, 10); break;
738 sig
->expires
= strtoul(cur_val
->str
, NULL
, 10); break;
740 sig
->bodylength
= strtol(cur_val
->str
, NULL
, 10); break;
742 sig
->headernames
= strdup(cur_val
->str
); break;
744 sig
->copiedheaders
= pdkim_decode_qp(cur_val
->str
); break;
746 DEBUG(D_acl
) debug_printf(" Unknown tag encountered\n");
750 pdkim_strclear(cur_tag
);
751 pdkim_strclear(cur_val
);
753 where
= PDKIM_HDR_LIMBO
;
756 pdkim_strncat(cur_val
, p
, 1);
767 /* Make sure the most important bits are there. */
768 if (!(sig
->domain
&& (*(sig
->domain
) != '\0') &&
769 sig
->selector
&& (*(sig
->selector
) != '\0') &&
770 sig
->headernames
&& (*(sig
->headernames
) != '\0') &&
780 /* Chomp raw header. The final newline must not be added to the signature. */
782 while (q
> sig
->rawsig_no_b_val
&& (*q
== '\r' || *q
== '\n'))
783 *q
= '\0'; q
--; /*XXX questionable code layout; possible bug */
788 "PDKIM >> Raw signature w/o b= tag value >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
789 pdkim_quoteprint(sig
->rawsig_no_b_val
, strlen(sig
->rawsig_no_b_val
), 1);
791 "PDKIM >> Sig size: %4d bits\n", sig
->sigdata_len
*8);
793 "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
798 SHA1_Init (&sig
->sha1_body
);
799 SHA256_Init(&sig
->sha2_body
);
801 #elif defined(SHA_GNUTLS)
803 gnutls_hash_init(&sig
->sha_body
,
804 sig
->algo
== PDKIM_ALGO_RSA_SHA1
? GNUTLS_DIG_SHA1
: GNUTLS_DIG_SHA256
);
806 #elif defined(SHA_POLARSSL)
808 if ( !(sig
->sha1_body
= malloc(sizeof(sha1_context
)))
809 || !(sig
->sha2_body
= malloc(sizeof(sha2_context
)))
816 sha1_starts(sig
->sha1_body
);
817 sha2_starts(sig
->sha2_body
, 0);
819 #endif /* SHA impl */
825 /* -------------------------------------------------------------------------- */
827 static pdkim_pubkey
*
828 pdkim_parse_pubkey_record(pdkim_ctx
*ctx
, char *raw_record
)
832 pdkim_str
*cur_tag
= NULL
;
833 pdkim_str
*cur_val
= NULL
;
834 int where
= PDKIM_HDR_LIMBO
;
836 if (!(pub
= malloc(sizeof(pdkim_pubkey
)))) return NULL
;
837 memset(pub
, 0, sizeof(pdkim_pubkey
));
839 for (p
= raw_record
; ; p
++)
844 if (c
== '\r' || c
== '\n')
847 if (where
== PDKIM_HDR_LIMBO
)
849 /* In limbo, just wait for a tag-char to appear */
850 if (!(c
>= 'a' && c
<= 'z'))
853 where
= PDKIM_HDR_TAG
;
856 if (where
== PDKIM_HDR_TAG
)
859 cur_tag
= pdkim_strnew(NULL
);
861 if (c
>= 'a' && c
<= 'z')
862 pdkim_strncat(cur_tag
, p
, 1);
866 where
= PDKIM_HDR_VALUE
;
871 if (where
== PDKIM_HDR_VALUE
)
874 cur_val
= pdkim_strnew(NULL
);
876 if (c
== '\r' || c
== '\n')
879 if (c
== ';' || c
== '\0')
881 if (cur_tag
->len
> 0)
883 pdkim_strtrim(cur_val
);
884 DEBUG(D_acl
) debug_printf(" %s=%s\n", cur_tag
->str
, cur_val
->str
);
886 switch (cur_tag
->str
[0])
889 /* This tag isn't evaluated because:
890 - We only support version DKIM1.
891 - Which is the default for this value (set below)
892 - Other versions are currently not specified. */
895 pub
->hashes
= strdup(cur_val
->str
); break;
897 pub
->granularity
= strdup(cur_val
->str
); break;
899 pub
->notes
= pdkim_decode_qp(cur_val
->str
); break;
901 pub
->key
= pdkim_decode_base64(cur_val
->str
, &(pub
->key_len
)); break;
903 pub
->hashes
= strdup(cur_val
->str
); break;
905 pub
->srvtype
= strdup(cur_val
->str
); break;
907 if (strchr(cur_val
->str
, 'y') != NULL
) pub
->testing
= 1;
908 if (strchr(cur_val
->str
, 's') != NULL
) pub
->no_subdomaining
= 1;
911 DEBUG(D_acl
) debug_printf(" Unknown tag encountered\n");
915 pdkim_strclear(cur_tag
);
916 pdkim_strclear(cur_val
);
917 where
= PDKIM_HDR_LIMBO
;
920 pdkim_strncat(cur_val
, p
, 1);
924 if (c
== '\0') break;
927 /* Set fallback defaults */
928 if (!pub
->version
) pub
->version
= strdup(PDKIM_PUB_RECORD_VERSION
);
929 if (!pub
->granularity
) pub
->granularity
= strdup("*");
930 if (!pub
->keytype
) pub
->keytype
= strdup("rsa");
931 if (!pub
->srvtype
) pub
->srvtype
= strdup("*");
937 pdkim_free_pubkey(pub
);
942 /* -------------------------------------------------------------------------- */
945 pdkim_update_bodyhash(pdkim_ctx
*ctx
, const char *data
, int len
)
947 pdkim_signature
*sig
= ctx
->sig
;
948 /* Cache relaxed version of data */
949 char *relaxed_data
= NULL
;
952 /* Traverse all signatures, updating their hashes. */
955 /* Defaults to simple canon (no further treatment necessary) */
956 const char *canon_data
= data
;
959 if (sig
->canon_body
== PDKIM_CANON_RELAXED
)
961 /* Relax the line if not done already */
964 BOOL seen_wsp
= FALSE
;
968 if (!(relaxed_data
= malloc(len
+1)))
969 return PDKIM_ERR_OOM
;
971 for (p
= data
; *p
; p
++)
976 if (q
> 0 && relaxed_data
[q
-1] == ' ')
979 else if (c
== '\t' || c
== ' ')
981 c
= ' '; /* Turns WSP into SP */
988 relaxed_data
[q
++] = c
;
990 relaxed_data
[q
] = '\0';
993 canon_data
= relaxed_data
;
994 canon_len
= relaxed_len
;
997 /* Make sure we don't exceed the to-be-signed body length */
998 if ( sig
->bodylength
>= 0
999 && sig
->signed_body_bytes
+ (unsigned long)canon_len
> sig
->bodylength
1001 canon_len
= sig
->bodylength
- sig
->signed_body_bytes
;
1006 gnutls_hash(sig
->sha_body
, canon_data
, canon_len
);
1008 if (sig
->algo
== PDKIM_ALGO_RSA_SHA1
)
1010 SHA1_Update (&sig
->sha1_body
, canon_data
, canon_len
);
1012 SHA256_Update(&sig
->sha2_body
, canon_data
, canon_len
);
1013 # elif defined(SHA_POLARSSL)
1014 sha1_update(sig
->sha1_body
, US canon_data
, canon_len
);
1016 sha2_update(sig
->sha2_body
, US canon_data
, canon_len
);
1020 sig
->signed_body_bytes
+= canon_len
;
1021 DEBUG(D_acl
) pdkim_quoteprint(canon_data
, canon_len
, 1);
1027 if (relaxed_data
) free(relaxed_data
);
1032 /* -------------------------------------------------------------------------- */
1035 pdkim_finish_bodyhash(pdkim_ctx
*ctx
)
1037 pdkim_signature
*sig
;
1039 /* Traverse all signatures */
1040 for (sig
= ctx
->sig
; sig
; sig
= sig
->next
)
1041 { /* Finish hashes */
1042 uschar bh
[32]; /* SHA-256 = 32 Bytes, SHA-1 = 20 Bytes */
1045 gnutls_hash_output(sig
->sha_body
, bh
);
1047 if (sig
->algo
== PDKIM_ALGO_RSA_SHA1
)
1049 SHA1_Final (bh
, &sig
->sha1_body
);
1051 SHA256_Final(bh
, &sig
->sha2_body
);
1052 # elif defined(SHA_POLARSSL)
1053 sha1_finish(sig
->sha1_body
, bh
);
1055 sha2_finish(sig
->sha2_body
, bh
);
1061 debug_printf("PDKIM [%s] Body bytes hashed: %lu\n"
1062 "PDKIM [%s] bh computed: ",
1063 sig
->domain
, sig
->signed_body_bytes
, sig
->domain
);
1064 pdkim_hexprint((char *)bh
, sig
->algo
== PDKIM_ALGO_RSA_SHA1
? 20 : 32, 1);
1067 /* SIGNING -------------------------------------------------------------- */
1068 if (ctx
->mode
== PDKIM_MODE_SIGN
)
1070 sig
->bodyhash_len
= sig
->algo
== PDKIM_ALGO_RSA_SHA1
? 20:32;
1071 sig
->bodyhash
= CS
string_copyn(US bh
, sig
->bodyhash_len
);
1073 /* If bodylength limit is set, and we have received less bytes
1074 than the requested amount, effectively remove the limit tag. */
1075 if (sig
->signed_body_bytes
< sig
->bodylength
)
1076 sig
->bodylength
= -1;
1079 /* VERIFICATION --------------------------------------------------------- */
1082 /* Compare bodyhash */
1083 if (memcmp(bh
, sig
->bodyhash
,
1084 (sig
->algo
== PDKIM_ALGO_RSA_SHA1
)?20:32) == 0)
1086 DEBUG(D_acl
) debug_printf("PDKIM [%s] Body hash verified OK\n", sig
->domain
);
1092 debug_printf("PDKIM [%s] bh signature: ", sig
->domain
);
1093 pdkim_hexprint(sig
->bodyhash
,
1094 sig
->algo
== PDKIM_ALGO_RSA_SHA1
? 20 : 32, 1);
1095 debug_printf("PDKIM [%s] Body hash did NOT verify\n", sig
->domain
);
1097 sig
->verify_status
= PDKIM_VERIFY_FAIL
;
1098 sig
->verify_ext_status
= PDKIM_VERIFY_FAIL_BODY
;
1108 /* -------------------------------------------------------------------------- */
1109 /* Callback from pdkim_feed below for processing complete body lines */
1112 pdkim_bodyline_complete(pdkim_ctx
*ctx
)
1114 char *p
= ctx
->linebuf
;
1115 int n
= ctx
->linebuf_offset
;
1116 pdkim_signature
*sig
= ctx
->sig
; /*XXX assumes only one sig */
1118 /* Ignore extra data if we've seen the end-of-data marker */
1119 if (ctx
->seen_eod
) goto BAIL
;
1121 /* We've always got one extra byte to stuff a zero ... */
1122 ctx
->linebuf
[ctx
->linebuf_offset
] = '\0';
1124 /* Terminate on EOD marker */
1125 if (memcmp(p
, ".\r\n", 3) == 0)
1127 /* In simple body mode, if any empty lines were buffered,
1128 replace with one. rfc 4871 3.4.3 */
1129 /*XXX checking the signed-body-bytes is a gross hack; I think
1130 it indicates that all linebreaks should be buffered, including
1131 the one terminating a text line */
1132 if ( sig
&& sig
->canon_body
== PDKIM_CANON_SIMPLE
1133 && sig
->signed_body_bytes
== 0
1134 && ctx
->num_buffered_crlf
> 0
1136 pdkim_update_bodyhash(ctx
, "\r\n", 2);
1138 ctx
->seen_eod
= TRUE
;
1142 if (memcmp(p
, "..", 2) == 0)
1148 /* Empty lines need to be buffered until we find a non-empty line */
1149 if (memcmp(p
, "\r\n", 2) == 0)
1151 ctx
->num_buffered_crlf
++;
1155 if (sig
&& sig
->canon_body
== PDKIM_CANON_RELAXED
)
1157 /* Lines with just spaces need to be buffered too */
1159 while (memcmp(check
, "\r\n", 2) != 0)
1163 if (c
!= '\t' && c
!= ' ')
1168 ctx
->num_buffered_crlf
++;
1173 /* At this point, we have a non-empty line, so release the buffered ones. */
1174 while (ctx
->num_buffered_crlf
)
1176 pdkim_update_bodyhash(ctx
, "\r\n", 2);
1177 ctx
->num_buffered_crlf
--;
1180 pdkim_update_bodyhash(ctx
, p
, n
);
1183 ctx
->linebuf_offset
= 0;
1188 /* -------------------------------------------------------------------------- */
1189 /* Callback from pdkim_feed below for processing complete headers */
1190 #define DKIM_SIGNATURE_HEADERNAME "DKIM-Signature:"
1193 pdkim_header_complete(pdkim_ctx
*ctx
)
1195 /* Special case: The last header can have an extra \r appended */
1196 if ( (ctx
->cur_header
->len
> 1) &&
1197 (ctx
->cur_header
->str
[(ctx
->cur_header
->len
)-1] == '\r') )
1199 ctx
->cur_header
->str
[(ctx
->cur_header
->len
)-1] = '\0';
1200 ctx
->cur_header
->len
--;
1204 if (ctx
->num_headers
> PDKIM_MAX_HEADERS
) goto BAIL
;
1206 /* SIGNING -------------------------------------------------------------- */
1207 if (ctx
->mode
== PDKIM_MODE_SIGN
)
1209 pdkim_signature
*sig
;
1211 for (sig
= ctx
->sig
; sig
; sig
= sig
->next
) /* Traverse all signatures */
1212 if (header_name_match(ctx
->cur_header
->str
,
1215 PDKIM_DEFAULT_SIGN_HEADERS
, 0) == PDKIM_OK
)
1217 pdkim_stringlist
*list
;
1219 /* Add header to the signed headers list (in reverse order) */
1220 if (!(list
= pdkim_prepend_stringlist(sig
->headers
,
1221 ctx
->cur_header
->str
)))
1222 return PDKIM_ERR_OOM
;
1223 sig
->headers
= list
;
1227 /* VERIFICATION ----------------------------------------------------------- */
1228 /* DKIM-Signature: headers are added to the verification list */
1229 if (ctx
->mode
== PDKIM_MODE_VERIFY
)
1231 if (strncasecmp(ctx
->cur_header
->str
,
1232 DKIM_SIGNATURE_HEADERNAME
,
1233 strlen(DKIM_SIGNATURE_HEADERNAME
)) == 0)
1235 pdkim_signature
*new_sig
;
1237 /* Create and chain new signature block */
1238 DEBUG(D_acl
) debug_printf(
1239 "PDKIM >> Found sig, trying to parse >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
1241 if ((new_sig
= pdkim_parse_sig_header(ctx
, ctx
->cur_header
->str
)))
1243 pdkim_signature
*last_sig
= ctx
->sig
;
1248 while (last_sig
->next
) last_sig
= last_sig
->next
;
1249 last_sig
->next
= new_sig
;
1253 DEBUG(D_acl
) debug_printf(
1254 "Error while parsing signature header\n"
1255 "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
1258 /* every other header is stored for signature verification */
1261 pdkim_stringlist
*list
;
1263 if (!(list
= pdkim_prepend_stringlist(ctx
->headers
, ctx
->cur_header
->str
)))
1264 return PDKIM_ERR_OOM
;
1265 ctx
->headers
= list
;
1270 pdkim_strclear(ctx
->cur_header
); /* Re-use existing pdkim_str */
1276 /* -------------------------------------------------------------------------- */
1277 #define HEADER_BUFFER_FRAG_SIZE 256
1280 pdkim_feed (pdkim_ctx
*ctx
, char *data
, int len
)
1284 for (p
= 0; p
<len
; p
++)
1288 if (ctx
->past_headers
)
1290 /* Processing body byte */
1291 ctx
->linebuf
[ctx
->linebuf_offset
++] = c
;
1294 int rc
= pdkim_bodyline_complete(ctx
); /* End of line */
1295 if (rc
!= PDKIM_OK
) return rc
;
1297 if (ctx
->linebuf_offset
== (PDKIM_MAX_BODY_LINE_LEN
-1))
1298 return PDKIM_ERR_LONG_LINE
;
1302 /* Processing header byte */
1309 int rc
= pdkim_header_complete(ctx
); /* Seen last header line */
1310 if (rc
!= PDKIM_OK
) return rc
;
1312 ctx
->past_headers
= TRUE
;
1314 DEBUG(D_acl
) debug_printf(
1315 "PDKIM >> Hashed body data, canonicalized >>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
1319 ctx
->seen_lf
= TRUE
;
1321 else if (ctx
->seen_lf
)
1323 if (!(c
== '\t' || c
== ' '))
1325 int rc
= pdkim_header_complete(ctx
); /* End of header */
1326 if (rc
!= PDKIM_OK
) return rc
;
1328 ctx
->seen_lf
= FALSE
;
1332 if (!ctx
->cur_header
)
1333 if (!(ctx
->cur_header
= pdkim_strnew(NULL
)))
1334 return PDKIM_ERR_OOM
;
1336 if (ctx
->cur_header
->len
< PDKIM_MAX_HEADER_LEN
)
1337 if (!pdkim_strncat(ctx
->cur_header
, &data
[p
], 1))
1338 return PDKIM_ERR_OOM
;
1345 * RFC 5322 specifies that header line length SHOULD be no more than 78
1350 * col: this int holds and receives column number (octets since last '\n')
1351 * str: partial string to append to
1352 * pad: padding, split line or space after before or after eg: ";"
1353 * intro: - must join to payload eg "h=", usually the tag name
1354 * payload: eg base64 data - long data can be split arbitrarily.
1356 * this code doesn't fold the header in some of the places that RFC4871
1357 * allows: As per RFC5322(2.2.3) it only folds before or after tag-value
1358 * pairs and inside long values. it also always spaces or breaks after the
1361 * no guarantees are made for output given out-of range input. like tag
1362 * names longer than 78, or bogus col. Input is assumed to be free of line breaks.
1366 pdkim_headcat(int *col
, pdkim_str
*str
, const char * pad
,
1367 const char *intro
, const char *payload
)
1376 pdkim_strcat(str
, "\r\n\t");
1379 pdkim_strncat(str
, pad
, l
);
1383 l
= (pad
?1:0) + (intro
?strlen(intro
):0);
1386 { /*can't fit intro - start a new line to make room.*/
1387 pdkim_strcat(str
, "\r\n\t");
1389 l
= intro
?strlen(intro
):0;
1392 l
+= payload
? strlen(payload
):0 ;
1395 { /* this fragment will not fit on a single line */
1398 pdkim_strcat(str
, " ");
1400 pad
= NULL
; /* only want this once */
1406 size_t sl
= strlen(intro
);
1408 pdkim_strncat(str
, intro
, sl
);
1411 intro
= NULL
; /* only want this once */
1416 size_t sl
= strlen(payload
);
1417 size_t chomp
= *col
+sl
< 77 ? sl
: 78-*col
;
1419 pdkim_strncat(str
, payload
, chomp
);
1425 /* the while precondition tells us it didn't fit. */
1426 pdkim_strcat(str
, "\r\n\t");
1432 pdkim_strcat(str
, "\r\n\t");
1439 pdkim_strcat(str
, " ");
1446 size_t sl
= strlen(intro
);
1448 pdkim_strncat(str
, intro
, sl
);
1456 size_t sl
= strlen(payload
);
1458 pdkim_strncat(str
, payload
, sl
);
1466 /* -------------------------------------------------------------------------- */
1469 pdkim_create_header(pdkim_signature
*sig
, int final
)
1472 char *base64_bh
= NULL
;
1473 char *base64_b
= NULL
;
1476 pdkim_str
*canon_all
;
1478 if (!(hdr
= pdkim_strnew("DKIM-Signature: v="PDKIM_SIGNATURE_VERSION
)))
1481 if (!(canon_all
= pdkim_strnew(pdkim_canons
[sig
->canon_headers
])))
1484 if (!(base64_bh
= pdkim_encode_base64(sig
->bodyhash
, sig
->bodyhash_len
)))
1487 col
= strlen(hdr
->str
);
1489 /* Required and static bits */
1490 if ( pdkim_headcat(&col
, hdr
, ";", "a=", pdkim_algos
[sig
->algo
])
1491 && pdkim_headcat(&col
, hdr
, ";", "q=", pdkim_querymethods
[sig
->querymethod
])
1492 && pdkim_strcat(canon_all
, "/")
1493 && pdkim_strcat(canon_all
, pdkim_canons
[sig
->canon_body
])
1494 && pdkim_headcat(&col
, hdr
, ";", "c=", canon_all
->str
)
1495 && pdkim_headcat(&col
, hdr
, ";", "d=", sig
->domain
)
1496 && pdkim_headcat(&col
, hdr
, ";", "s=", sig
->selector
)
1499 /* list of eader names can be split between items. */
1501 char *n
= strdup(sig
->headernames
);
1509 char *c
= strchr(n
, ':');
1514 if (!pdkim_headcat(&col
, hdr
, NULL
, NULL
, ":"))
1520 if (!pdkim_headcat(&col
, hdr
, s
, i
, n
))
1536 if(!pdkim_headcat(&col
, hdr
, ";", "bh=", base64_bh
))
1541 if(!pdkim_headcat(&col
, hdr
, ";", "i=", sig
->identity
))
1544 if (sig
->created
> 0)
1548 snprintf(minibuf
, 20, "%lu", sig
->created
);
1549 if(!pdkim_headcat(&col
, hdr
, ";", "t=", minibuf
))
1553 if (sig
->expires
> 0)
1557 snprintf(minibuf
, 20, "%lu", sig
->expires
);
1558 if(!pdkim_headcat(&col
, hdr
, ";", "x=", minibuf
))
1562 if (sig
->bodylength
>= 0)
1566 snprintf(minibuf
, 20, "%lu", sig
->bodylength
);
1567 if(!pdkim_headcat(&col
, hdr
, ";", "l=", minibuf
))
1571 /* Preliminary or final version? */
1574 if (!(base64_b
= pdkim_encode_base64(sig
->sigdata
, sig
->sigdata_len
)))
1576 if (!pdkim_headcat(&col
, hdr
, ";", "b=", base64_b
))
1580 if(!pdkim_headcat(&col
, hdr
, ";", "b=", ""))
1583 /* add trailing semicolon: I'm not sure if this is actually needed */
1584 if (!pdkim_headcat(&col
, hdr
, NULL
, ";", ""))
1588 rc
= strdup(hdr
->str
);
1592 if (canon_all
) pdkim_strfree(canon_all
);
1597 /* -------------------------------------------------------------------------- */
1600 pdkim_feed_finish(pdkim_ctx
*ctx
, pdkim_signature
**return_signatures
)
1602 pdkim_signature
*sig
= ctx
->sig
;
1603 pdkim_str
*headernames
= NULL
; /* Collected signed header names */
1605 /* Check if we must still flush a (partial) header. If that is the
1606 case, the message has no body, and we must compute a body hash
1607 out of '<CR><LF>' */
1608 if (ctx
->cur_header
&& ctx
->cur_header
->len
)
1610 int rc
= pdkim_header_complete(ctx
);
1611 if (rc
!= PDKIM_OK
) return rc
;
1612 pdkim_update_bodyhash(ctx
, "\r\n", 2);
1615 DEBUG(D_acl
) debug_printf(
1616 "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
1618 /* Build (and/or evaluate) body hash */
1619 if (pdkim_finish_bodyhash(ctx
) != PDKIM_OK
)
1620 return PDKIM_ERR_OOM
;
1622 /* SIGNING -------------------------------------------------------------- */
1623 if (ctx
->mode
== PDKIM_MODE_SIGN
)
1624 if (!(headernames
= pdkim_strnew(NULL
)))
1625 return PDKIM_ERR_OOM
;
1626 /* ---------------------------------------------------------------------- */
1631 SHA_CTX sha1_headers
;
1632 SHA256_CTX sha2_headers
;
1633 #elif defined(SHA_GNUTLS)
1634 gnutls_hash_hd_t sha_headers
;
1635 #elif defined(SHA_POLARSSL)
1636 sha1_context sha1_headers
;
1637 sha2_context sha2_headers
;
1641 char headerhash
[32];
1644 uschar
* hdata
= NULL
;
1645 int hdata_alloc
= 0;
1650 gnutls_hash_init(&sha_headers
,
1651 sig
->algo
== PDKIM_ALGO_RSA_SHA1
? GNUTLS_DIG_SHA1
: GNUTLS_DIG_SHA256
);
1653 if (sig
->algo
== PDKIM_ALGO_RSA_SHA1
)
1655 SHA1_Init(&sha1_headers
);
1657 SHA256_Init(&sha2_headers
);
1658 # elif defined(SHA_POLARSSL)
1659 sha1_starts(&sha1_headers
);
1661 sha2_starts(&sha2_headers
, 0);
1665 DEBUG(D_acl
) debug_printf(
1666 "PDKIM >> Hashed header data, canonicalized, in sequence >>>>>>>>>>>>>>\n");
1668 /* SIGNING ---------------------------------------------------------------- */
1669 /* When signing, walk through our header list and add them to the hash. As we
1670 go, construct a list of the header's names to use for the h= parameter. */
1672 if (ctx
->mode
== PDKIM_MODE_SIGN
)
1674 pdkim_stringlist
*p
;
1676 for (p
= sig
->headers
; p
; p
= p
->next
)
1679 /* Collect header names (Note: colon presence is guaranteed here) */
1680 char *q
= strchr(p
->value
, ':');
1682 if (!(pdkim_strncat(headernames
, p
->value
,
1683 (q
-(p
->value
)) + (p
->next
? 1 : 0))))
1684 return PDKIM_ERR_OOM
;
1686 rh
= sig
->canon_headers
== PDKIM_CANON_RELAXED
1687 ? pdkim_relax_header(p
->value
, 1) /* cook header for relaxed canon */
1688 : strdup(p
->value
); /* just copy it for simple canon */
1690 return PDKIM_ERR_OOM
;
1692 /* Feed header to the hash algorithm */
1694 gnutls_hash(sha_headers
, rh
, strlen(rh
));
1696 if (sig
->algo
== PDKIM_ALGO_RSA_SHA1
)
1698 SHA1_Update (&sha1_headers
, rh
, strlen(rh
));
1700 SHA256_Update(&sha2_headers
, rh
, strlen(rh
));
1701 # elif defined(SHA_POLARSSL)
1702 sha1_update(&sha1_headers
, US rh
, strlen(rh
));
1704 sha2_update(&sha2_headers
, US rh
, strlen(rh
));
1709 /* Remember headers block for signing */
1710 hdata
= string_append(hdata
, &hdata_alloc
, &hdata_size
, 1, rh
);
1713 DEBUG(D_acl
) pdkim_quoteprint(rh
, strlen(rh
), 1);
1718 /* VERIFICATION ----------------------------------------------------------- */
1719 /* When verifying, walk through the header name list in the h= parameter and
1720 add the headers to the hash in that order. */
1723 char *b
= strdup(sig
->headernames
);
1726 pdkim_stringlist
*hdrs
;
1728 if (!b
) return PDKIM_ERR_OOM
;
1731 for (hdrs
= ctx
->headers
; hdrs
; hdrs
= hdrs
->next
)
1736 if ((q
= strchr(p
, ':')))
1739 for (hdrs
= ctx
->headers
; hdrs
; hdrs
= hdrs
->next
)
1741 && strncasecmp(hdrs
->value
, p
, strlen(p
)) == 0
1742 && (hdrs
->value
)[strlen(p
)] == ':'
1747 rh
= sig
->canon_headers
== PDKIM_CANON_RELAXED
1748 ? pdkim_relax_header(hdrs
->value
, 1) /* cook header for relaxed canon */
1749 : strdup(hdrs
->value
); /* just copy it for simple canon */
1751 return PDKIM_ERR_OOM
;
1753 /* Feed header to the hash algorithm */
1755 gnutls_hash(sha_headers
, rh
, strlen(rh
));
1757 if (sig
->algo
== PDKIM_ALGO_RSA_SHA1
)
1759 SHA1_Update (&sha1_headers
, rh
, strlen(rh
));
1761 SHA256_Update(&sha2_headers
, rh
, strlen(rh
));
1762 # elif defined(SHA_POLARSSL)
1763 sha1_update(&sha1_headers
, US rh
, strlen(rh
));
1765 sha2_update(&sha2_headers
, US rh
, strlen(rh
));
1769 DEBUG(D_acl
) pdkim_quoteprint(rh
, strlen(rh
), 1);
1781 DEBUG(D_acl
) debug_printf(
1782 "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
1784 /* SIGNING ---------------------------------------------------------------- */
1785 if (ctx
->mode
== PDKIM_MODE_SIGN
)
1787 /* Copy headernames to signature struct */
1788 sig
->headernames
= strdup(headernames
->str
);
1789 pdkim_strfree(headernames
);
1791 /* Create signature header with b= omitted */
1792 sig_hdr
= pdkim_create_header(ctx
->sig
, 0);
1795 /* VERIFICATION ----------------------------------------------------------- */
1797 sig_hdr
= strdup(sig
->rawsig_no_b_val
);
1798 /* ------------------------------------------------------------------------ */
1801 return PDKIM_ERR_OOM
;
1803 /* Relax header if necessary */
1804 if (sig
->canon_headers
== PDKIM_CANON_RELAXED
)
1806 char *relaxed_hdr
= pdkim_relax_header(sig_hdr
, 0);
1810 return PDKIM_ERR_OOM
;
1811 sig_hdr
= relaxed_hdr
;
1817 "PDKIM >> Signed DKIM-Signature header, canonicalized >>>>>>>>>>>>>>>>>\n");
1818 pdkim_quoteprint(sig_hdr
, strlen(sig_hdr
), 1);
1820 "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
1823 /* Finalize header hash */
1825 gnutls_hash(sha_headers
, sig_hdr
, strlen(sig_hdr
));
1826 gnutls_hash_output(sha_headers
, headerhash
);
1828 if (sig
->algo
== PDKIM_ALGO_RSA_SHA1
)
1831 SHA1_Update(&sha1_headers
, sig_hdr
, strlen(sig_hdr
));
1832 SHA1_Final(US headerhash
, &sha1_headers
);
1836 SHA256_Update(&sha2_headers
, sig_hdr
, strlen(sig_hdr
));
1837 SHA256_Final(US headerhash
, &sha2_headers
);
1839 # elif defined(SHA_POLARSSL)
1841 sha1_update(&sha1_headers
, US sig_hdr
, strlen(sig_hdr
));
1842 sha1_finish(&sha1_headers
, US headerhash
);
1846 sha2_update(&sha2_headers
, US sig_hdr
, strlen(sig_hdr
));
1847 sha2_finish(&sha2_headers
, US headerhash
);
1854 debug_printf("PDKIM [%s] hh computed: ", sig
->domain
);
1855 pdkim_hexprint(headerhash
, sig
->algo
== PDKIM_ALGO_RSA_SHA1
? 20:32, 1);
1859 if (ctx
->mode
== PDKIM_MODE_SIGN
)
1860 hdata
= string_append(hdata
, &hdata_alloc
, &hdata_size
, 1, sig_hdr
);
1865 /* SIGNING ---------------------------------------------------------------- */
1866 if (ctx
->mode
== PDKIM_MODE_SIGN
)
1872 #elif defined(RSA_GNUTLS)
1873 gnutls_x509_privkey_t rsa
;
1879 /* Import private key */
1882 if ( !(p
= Ustrstr(sig
->rsa_privkey
, "-----BEGIN RSA PRIVATE KEY-----"))
1883 || !(q
= Ustrstr(p
+=31, "-----END RSA PRIVATE KEY-----"))
1885 return PDKIM_SIGN_PRIVKEY_WRAP
;
1887 if ((len
= b64decode(p
, &p
)) < 0)
1889 DEBUG(D_acl
) debug_printf("b64decode failed\n");
1890 return PDKIM_SIGN_PRIVKEY_B64D
;
1892 if (!(rsa
= d2i_RSAPrivateKey(NULL
, CUSS
&p
, len
)))
1896 char ssl_errstring
[256];
1897 ERR_error_string(ERR_get_error(), ssl_errstring
);
1898 debug_printf("d2i_RSAPrivateKey: %s\n", ssl_errstring
);
1900 return PDKIM_ERR_RSA_PRIVKEY
;
1903 #elif defined(RSA_GNUTLS)
1905 k
.data
= sig
->rsa_privkey
;
1906 k
.size
= strlen(sig
->rsa_privkey
);
1907 if ( (rc
= gnutls_x509_privkey_init(&rsa
)) != GNUTLS_E_SUCCESS
1908 || (rc
= gnutls_x509_privkey_import2(rsa
, &k
,
1909 GNUTLS_X509_FMT_PEM
, NULL
, GNUTLS_PKCS_PLAIN
)) != GNUTLS_E_SUCCESS
1912 DEBUG(D_acl
) debug_printf("gnutls_x509_privkey_import2: %s\n",
1913 gnutls_strerror(rc
));
1914 return PDKIM_ERR_RSA_PRIVKEY
;
1920 /* Allocate mem for signature */
1922 sig
->sigdata
= store_get(RSA_size(rsa
));
1923 #elif defined(RSA_GNUTLS)
1925 k
.size
= hdata_size
;
1926 (void) gnutls_x509_privkey_sign_data(rsa
,
1927 sig
->algo
== PDKIM_ALGO_RSA_SHA1
? GNUTLS_DIG_SHA1
: GNUTLS_DIG_SHA256
,
1928 0, &k
, NULL
, &sigsize
);
1929 sig
->sigdata
= store_get(sig
->sigdata_len
= sigsize
);
1935 if (RSA_sign(sig
->algo
== PDKIM_ALGO_RSA_SHA1
? NID_sha1
: NID_sha256
,
1936 CUS headerhash
, sig
->algo
== PDKIM_ALGO_RSA_SHA1
? 20 : 32,
1937 US sig
->sigdata
, (unsigned int *)&sig
->sigdata_len
,
1939 return PDKIM_ERR_RSA_SIGNING
;
1942 #elif defined(RSA_GNUTLS)
1944 if ((rc
= gnutls_x509_privkey_sign_data(rsa
,
1945 sig
->algo
== PDKIM_ALGO_RSA_SHA1
? GNUTLS_DIG_SHA1
: GNUTLS_DIG_SHA256
,
1946 0, &k
, sig
->sigdata
, &sigsize
)) != GNUTLS_E_SUCCESS
1949 DEBUG(D_acl
) debug_printf("gnutls_x509_privkey_sign_data: %s\n",
1950 gnutls_strerror(rc
));
1951 return PDKIM_ERR_RSA_SIGNING
;
1953 gnutls_x509_privkey_deinit(rsa
);
1960 debug_printf( "PDKIM [%s] b computed: ", sig
->domain
);
1961 pdkim_hexprint(sig
->sigdata
, sig
->sigdata_len
, 1);
1964 if (!(sig
->signature_header
= pdkim_create_header(ctx
->sig
, 1)))
1965 return PDKIM_ERR_OOM
;
1968 /* VERIFICATION ----------------------------------------------------------- */
1973 const unsigned char * p
;
1974 #elif defined(RSA_GNUTLS)
1975 gnutls_pubkey_t rsa
;
1976 gnutls_datum_t k
, s
;
1979 char *dns_txt_name
, *dns_txt_reply
;
1982 gnutls_pubkey_init(&rsa
);
1985 /* Fetch public key for signing domain, from DNS */
1987 if (!(dns_txt_name
= malloc(PDKIM_DNS_TXT_MAX_NAMELEN
)))
1988 return PDKIM_ERR_OOM
;
1990 if (!(dns_txt_reply
= malloc(PDKIM_DNS_TXT_MAX_RECLEN
)))
1993 return PDKIM_ERR_OOM
;
1996 memset(dns_txt_reply
, 0, PDKIM_DNS_TXT_MAX_RECLEN
);
1997 memset(dns_txt_name
, 0, PDKIM_DNS_TXT_MAX_NAMELEN
);
1999 if (snprintf(dns_txt_name
, PDKIM_DNS_TXT_MAX_NAMELEN
,
2000 "%s._domainkey.%s.",
2001 sig
->selector
, sig
->domain
) >= PDKIM_DNS_TXT_MAX_NAMELEN
)
2003 sig
->verify_status
= PDKIM_VERIFY_INVALID
;
2004 sig
->verify_ext_status
= PDKIM_VERIFY_INVALID_BUFFER_SIZE
;
2008 if ( ctx
->dns_txt_callback(dns_txt_name
, dns_txt_reply
) != PDKIM_OK
2009 || dns_txt_reply
[0] == '\0')
2011 sig
->verify_status
= PDKIM_VERIFY_INVALID
;
2012 sig
->verify_ext_status
= PDKIM_VERIFY_INVALID_PUBKEY_UNAVAILABLE
;
2019 "PDKIM >> Parsing public key record >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n"
2021 pdkim_quoteprint(dns_txt_reply
, strlen(dns_txt_reply
), 1);
2024 if (!(sig
->pubkey
= pdkim_parse_pubkey_record(ctx
, dns_txt_reply
)))
2026 sig
->verify_status
= PDKIM_VERIFY_INVALID
;
2027 sig
->verify_ext_status
= PDKIM_VERIFY_INVALID_PUBKEY_DNSRECORD
;
2029 DEBUG(D_acl
) debug_printf(
2030 " Error while parsing public key record\n"
2031 "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
2035 DEBUG(D_acl
) debug_printf(
2036 "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
2038 /* Import public key */
2041 p
= CUS sig
->pubkey
->key
;
2042 if (!(rsa
= d2i_RSA_PUBKEY(NULL
, &p
, (long) sig
->pubkey
->key_len
)))
2044 #elif defined(RSA_GNUTLS)
2046 k
.data
= sig
->pubkey
->key
;
2047 k
.size
= sig
->pubkey
->key_len
;
2048 if ((rc
= gnutls_pubkey_import(rsa
, &k
, GNUTLS_X509_FMT_DER
))
2049 != GNUTLS_E_SUCCESS
)
2057 ERR_load_crypto_strings(); /*XXX move to a startup routine */
2058 while ((e
= ERR_get_error()))
2059 debug_printf("Az: %.120s\n", ERR_error_string(e
, NULL
));
2060 #elif defined(RSA_GNUTLS)
2061 debug_printf("gnutls_pubkey_import: %s\n", gnutls_strerror(rc
));
2065 sig
->verify_status
= PDKIM_VERIFY_INVALID
;
2066 sig
->verify_ext_status
= PDKIM_VERIFY_INVALID_PUBKEY_IMPORT
;
2070 /* Check the signature */
2073 if (RSA_verify(sig
->algo
== PDKIM_ALGO_RSA_SHA1
? NID_sha1
: NID_sha256
,
2074 CUS headerhash
, sig
->algo
== PDKIM_ALGO_RSA_SHA1
? 20 : 32,
2075 US sig
->sigdata
, (unsigned int)sig
->sigdata_len
,
2078 #elif defined(RSA_GNUTLS)
2080 k
.data
= headerhash
;
2081 k
.size
= sig
->algo
== PDKIM_ALGO_RSA_SHA1
? 20 : 32;
2082 s
.data
= sig
->sigdata
;
2083 s
.size
= sig
->sigdata_len
;
2084 if ((rc
= gnutls_pubkey_verify_hash2(rsa
,
2085 sig
->algo
== PDKIM_ALGO_RSA_SHA1
2086 ? GNUTLS_SIGN_RSA_SHA1
: GNUTLS_SIGN_RSA_SHA256
,
2091 #if defined(RSA_GNUTLS)
2092 debug_printf("gnutls_pubkey_verify_hash2: %s\n", gnutls_strerror(rc
));
2094 sig
->verify_status
= PDKIM_VERIFY_FAIL
;
2095 sig
->verify_ext_status
= PDKIM_VERIFY_FAIL_MESSAGE
;
2099 /* We have a winner! (if bodydhash was correct earlier) */
2100 if (sig
->verify_status
== PDKIM_VERIFY_NONE
)
2101 sig
->verify_status
= PDKIM_VERIFY_PASS
;
2107 debug_printf("PDKIM [%s] signature status: %s",
2108 sig
->domain
, pdkim_verify_status_str(sig
->verify_status
));
2109 if (sig
->verify_ext_status
> 0)
2110 debug_printf(" (%s)\n",
2111 pdkim_verify_ext_status_str(sig
->verify_ext_status
));
2117 gnutls_pubkey_deinit(rsa
);
2120 free(dns_txt_reply
);
2126 /* If requested, set return pointer to signature(s) */
2127 if (return_signatures
)
2128 *return_signatures
= ctx
->sig
;
2134 /* -------------------------------------------------------------------------- */
2136 DLLEXPORT pdkim_ctx
*
2137 pdkim_init_verify(int(*dns_txt_callback
)(char *, char *))
2139 pdkim_ctx
*ctx
= malloc(sizeof(pdkim_ctx
));
2143 memset(ctx
, 0, sizeof(pdkim_ctx
));
2145 if (!(ctx
->linebuf
= malloc(PDKIM_MAX_BODY_LINE_LEN
)))
2151 ctx
->mode
= PDKIM_MODE_VERIFY
;
2152 ctx
->dns_txt_callback
= dns_txt_callback
;
2158 /* -------------------------------------------------------------------------- */
2160 DLLEXPORT pdkim_ctx
*
2161 pdkim_init_sign(char *domain
, char *selector
, char *rsa_privkey
, int algo
)
2164 pdkim_signature
*sig
;
2166 if (!domain
|| !selector
|| !rsa_privkey
)
2169 if (!(ctx
= malloc(sizeof(pdkim_ctx
))))
2171 memset(ctx
, 0, sizeof(pdkim_ctx
));
2173 if (!(ctx
->linebuf
= malloc(PDKIM_MAX_BODY_LINE_LEN
)))
2179 if (!(sig
= malloc(sizeof(pdkim_signature
))))
2185 memset(sig
, 0, sizeof(pdkim_signature
));
2187 sig
->bodylength
= -1;
2189 ctx
->mode
= PDKIM_MODE_SIGN
;
2192 ctx
->sig
->domain
= strdup(domain
);
2193 ctx
->sig
->selector
= strdup(selector
);
2194 ctx
->sig
->rsa_privkey
= strdup(rsa_privkey
);
2195 ctx
->sig
->algo
= algo
;
2197 if (!ctx
->sig
->domain
|| !ctx
->sig
->selector
|| !ctx
->sig
->rsa_privkey
)
2201 SHA1_Init (&ctx
->sig
->sha1_body
);
2202 SHA256_Init(&ctx
->sig
->sha2_body
);
2204 #elif defined(SHA_GNUTLS)
2205 gnutls_hash_init(&ctx
->sig
->sha_body
,
2206 algo
== PDKIM_ALGO_RSA_SHA1
? GNUTLS_DIG_SHA1
: GNUTLS_DIG_SHA256
);
2208 #elif defined(SHA_POLARSSL)
2209 if (!(ctx
->sig
->sha1_body
= malloc(sizeof(sha1_context
))))
2211 sha1_starts(ctx
->sig
->sha1_body
);
2213 if (!(ctx
->sig
->sha2_body
= malloc(sizeof(sha2_context
))))
2215 sha2_starts(ctx
->sig
->sha2_body
, 0);
2222 pdkim_free_ctx(ctx
);
2227 /* -------------------------------------------------------------------------- */
2230 pdkim_set_optional(pdkim_ctx
*ctx
,
2236 unsigned long created
,
2237 unsigned long expires
)
2240 if (!(ctx
->sig
->identity
= strdup(identity
)))
2241 return PDKIM_ERR_OOM
;
2244 if (!(ctx
->sig
->sign_headers
= strdup(sign_headers
)))
2245 return PDKIM_ERR_OOM
;
2247 ctx
->sig
->canon_headers
= canon_headers
;
2248 ctx
->sig
->canon_body
= canon_body
;
2249 ctx
->sig
->bodylength
= bodylength
;
2250 ctx
->sig
->created
= created
;
2251 ctx
->sig
->expires
= expires
;
2257 #endif /*DISABLE_DKIM*/