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>
47 #define PDKIM_SIGNATURE_VERSION "1"
48 #define PDKIM_PUB_RECORD_VERSION US "DKIM1"
50 #define PDKIM_MAX_HEADER_LEN 65536
51 #define PDKIM_MAX_HEADERS 512
52 #define PDKIM_MAX_BODY_LINE_LEN 16384
53 #define PDKIM_DNS_TXT_MAX_NAMELEN 1024
54 #define PDKIM_DEFAULT_SIGN_HEADERS "From:Sender:Reply-To:Subject:Date:"\
55 "Message-ID:To:Cc:MIME-Version:Content-Type:"\
56 "Content-Transfer-Encoding:Content-ID:"\
57 "Content-Description:Resent-Date:Resent-From:"\
58 "Resent-Sender:Resent-To:Resent-Cc:"\
59 "Resent-Message-ID:In-Reply-To:References:"\
60 "List-Id:List-Help:List-Unsubscribe:"\
61 "List-Subscribe:List-Post:List-Owner:List-Archive"
63 /* -------------------------------------------------------------------------- */
64 struct pdkim_stringlist {
70 /* -------------------------------------------------------------------------- */
71 /* A bunch of list constants */
72 const uschar * pdkim_querymethods[] = {
76 const uschar * pdkim_algos[] = {
81 const uschar * pdkim_canons[] = {
86 const uschar * pdkim_hashes[] = {
91 const uschar * pdkim_keytypes[] = {
96 typedef struct pdkim_combined_canon_entry {
100 } pdkim_combined_canon_entry;
102 pdkim_combined_canon_entry pdkim_combined_canons[] = {
103 { US"simple/simple", PDKIM_CANON_SIMPLE, PDKIM_CANON_SIMPLE },
104 { US"simple/relaxed", PDKIM_CANON_SIMPLE, PDKIM_CANON_RELAXED },
105 { US"relaxed/simple", PDKIM_CANON_RELAXED, PDKIM_CANON_SIMPLE },
106 { US"relaxed/relaxed", PDKIM_CANON_RELAXED, PDKIM_CANON_RELAXED },
107 { US"simple", PDKIM_CANON_SIMPLE, PDKIM_CANON_SIMPLE },
108 { US"relaxed", PDKIM_CANON_RELAXED, PDKIM_CANON_SIMPLE },
113 /* -------------------------------------------------------------------------- */
116 pdkim_verify_status_str(int status)
120 case PDKIM_VERIFY_NONE: return "PDKIM_VERIFY_NONE";
121 case PDKIM_VERIFY_INVALID: return "PDKIM_VERIFY_INVALID";
122 case PDKIM_VERIFY_FAIL: return "PDKIM_VERIFY_FAIL";
123 case PDKIM_VERIFY_PASS: return "PDKIM_VERIFY_PASS";
124 default: return "PDKIM_VERIFY_UNKNOWN";
129 pdkim_verify_ext_status_str(int ext_status)
133 case PDKIM_VERIFY_FAIL_BODY: return "PDKIM_VERIFY_FAIL_BODY";
134 case PDKIM_VERIFY_FAIL_MESSAGE: return "PDKIM_VERIFY_FAIL_MESSAGE";
135 case PDKIM_VERIFY_INVALID_PUBKEY_UNAVAILABLE: return "PDKIM_VERIFY_INVALID_PUBKEY_UNAVAILABLE";
136 case PDKIM_VERIFY_INVALID_BUFFER_SIZE: return "PDKIM_VERIFY_INVALID_BUFFER_SIZE";
137 case PDKIM_VERIFY_INVALID_PUBKEY_DNSRECORD: return "PDKIM_VERIFY_INVALID_PUBKEY_DNSRECORD";
138 case PDKIM_VERIFY_INVALID_PUBKEY_IMPORT: return "PDKIM_VERIFY_INVALID_PUBKEY_IMPORT";
139 case PDKIM_VERIFY_INVALID_SIGNATURE_ERROR: return "PDKIM_VERIFY_INVALID_SIGNATURE_ERROR";
140 case PDKIM_VERIFY_INVALID_DKIM_VERSION: return "PDKIM_VERIFY_INVALID_DKIM_VERSION";
141 default: return "PDKIM_VERIFY_UNKNOWN";
146 pdkim_errstr(int status)
150 case PDKIM_OK: return "OK";
151 case PDKIM_FAIL: return "FAIL";
152 case PDKIM_ERR_RSA_PRIVKEY: return "RSA_PRIVKEY";
153 case PDKIM_ERR_RSA_SIGNING: return "RSA SIGNING";
154 case PDKIM_ERR_LONG_LINE: return "RSA_LONG_LINE";
155 case PDKIM_ERR_BUFFER_TOO_SMALL: return "BUFFER_TOO_SMALL";
156 case PDKIM_SIGN_PRIVKEY_WRAP: return "PRIVKEY_WRAP";
157 case PDKIM_SIGN_PRIVKEY_B64D: return "PRIVKEY_B64D";
158 default: return "(unknown)";
163 /* -------------------------------------------------------------------------- */
164 /* Print debugging functions */
166 pdkim_quoteprint(const uschar *data, int len)
169 for (i = 0; i < len; i++)
171 const int c = data[i];
174 case ' ' : debug_printf("{SP}"); break;
175 case '\t': debug_printf("{TB}"); break;
176 case '\r': debug_printf("{CR}"); break;
177 case '\n': debug_printf("{LF}"); break;
178 case '{' : debug_printf("{BO}"); break;
179 case '}' : debug_printf("{BC}"); break;
181 if ( (c < 32) || (c > 127) )
182 debug_printf("{%02x}", c);
184 debug_printf("%c", c);
192 pdkim_hexprint(const uschar *data, int len)
195 for (i = 0 ; i < len; i++) debug_printf("%02x", data[i]);
201 static pdkim_stringlist *
202 pdkim_prepend_stringlist(pdkim_stringlist * base, const uschar * str)
204 pdkim_stringlist * new_entry = store_get(sizeof(pdkim_stringlist));
206 memset(new_entry, 0, sizeof(pdkim_stringlist));
207 new_entry->value = string_copy(str);
208 if (base) new_entry->next = base;
214 /* Trim whitespace fore & aft */
217 pdkim_strtrim(uschar * str)
221 while (*p == '\t' || *p == ' ') p++; /* skip whitespace */
222 while (*p) {*q = *p; q++; p++;} /* dump the leading whitespace */
224 while (q != str && ( (*q == '\0') || (*q == '\t') || (*q == ' ') ) )
225 { /* dump trailing whitespace */
233 /* -------------------------------------------------------------------------- */
236 pdkim_free_ctx(pdkim_ctx *ctx)
241 /* -------------------------------------------------------------------------- */
242 /* Matches the name of the passed raw "header" against
243 the passed colon-separated "tick", and invalidates
244 the entry in tick. Returns OK or fail-code */
245 /*XXX might be safer done using a pdkim_stringlist for "tick" */
248 header_name_match(const uschar * header, uschar * tick)
254 uschar * hcolon = Ustrchr(header, ':'); /* Get header name */
257 return PDKIM_FAIL; /* This isn't a header */
259 /* if we had strncmpic() we wouldn't need this copy */
260 hname = string_copyn(header, hcolon-header);
262 /* Copy tick-off list locally, so we can punch zeroes into it */
263 p = lcopy = string_copy(tick);
265 for (q = Ustrchr(p, ':'); q; q = Ustrchr(p, ':'))
268 if (strcmpic(p, hname) == 0)
274 if (strcmpic(p, hname) == 0)
280 /* Invalidate header name instance in tick-off list */
286 /* -------------------------------------------------------------------------- */
287 /* Performs "relaxed" canonicalization of a header. */
290 pdkim_relax_header(const uschar * header, int crlf)
292 BOOL past_field_name = FALSE;
293 BOOL seen_wsp = FALSE;
295 uschar * relaxed = store_get(Ustrlen(header)+3);
296 uschar * q = relaxed;
298 for (p = header; *p; p++)
302 if (c == '\r' || c == '\n')
304 if (c == '\t' || c == ' ')
308 c = ' '; /* Turns WSP into SP */
312 if (!past_field_name && c == ':')
314 if (seen_wsp) q--; /* This removes WSP before the colon */
315 seen_wsp = TRUE; /* This removes WSP after the colon */
316 past_field_name = TRUE;
321 /* Lowercase header name */
322 if (!past_field_name) c = tolower(c);
326 if (q > relaxed && q[-1] == ' ') q--; /* Squash eventual trailing SP */
328 if (crlf) { *q++ = '\r'; *q++ = '\n'; }
334 /* -------------------------------------------------------------------------- */
335 #define PDKIM_QP_ERROR_DECODE -1
338 pdkim_decode_qp_char(uschar *qp_p, int *c)
340 uschar *initial_pos = qp_p;
342 /* Advance one char */
345 /* Check for two hex digits and decode them */
346 if (isxdigit(*qp_p) && isxdigit(qp_p[1]))
348 /* Do hex conversion */
349 *c = (isdigit(*qp_p) ? *qp_p - '0' : toupper(*qp_p) - 'A' + 10) << 4;
350 *c |= isdigit(qp_p[1]) ? qp_p[1] - '0' : toupper(qp_p[1]) - 'A' + 10;
354 /* Illegal char here */
355 *c = PDKIM_QP_ERROR_DECODE;
360 /* -------------------------------------------------------------------------- */
363 pdkim_decode_qp(uschar * str)
368 uschar * n = store_get(Ustrlen(str)+1);
376 p = pdkim_decode_qp_char(p, &nchar);
392 /* -------------------------------------------------------------------------- */
395 pdkim_decode_base64(uschar *str, blob * b)
398 dlen = b64decode(str, &b->data);
399 if (dlen < 0) b->data = NULL;
404 pdkim_encode_base64(blob * b)
406 return b64encode(b->data, b->len);
410 /* -------------------------------------------------------------------------- */
411 #define PDKIM_HDR_LIMBO 0
412 #define PDKIM_HDR_TAG 1
413 #define PDKIM_HDR_VALUE 2
415 static pdkim_signature *
416 pdkim_parse_sig_header(pdkim_ctx *ctx, uschar * raw_hdr)
418 pdkim_signature *sig ;
420 uschar * cur_tag = NULL; int ts = 0, tl = 0;
421 uschar * cur_val = NULL; int vs = 0, vl = 0;
422 BOOL past_hname = FALSE;
423 BOOL in_b_val = FALSE;
424 int where = PDKIM_HDR_LIMBO;
427 sig = store_get(sizeof(pdkim_signature));
428 memset(sig, 0, sizeof(pdkim_signature));
429 sig->bodylength = -1;
431 /* Set so invalid/missing data error display is accurate */
435 q = sig->rawsig_no_b_val = store_get(Ustrlen(raw_hdr)+1);
437 for (p = raw_hdr; ; p++)
442 if (c == '\r' || c == '\n')
445 /* Fast-forward through header name */
448 if (c == ':') past_hname = TRUE;
452 if (where == PDKIM_HDR_LIMBO)
454 /* In limbo, just wait for a tag-char to appear */
455 if (!(c >= 'a' && c <= 'z'))
458 where = PDKIM_HDR_TAG;
461 if (where == PDKIM_HDR_TAG)
463 if (c >= 'a' && c <= 'z')
464 cur_tag = string_catn(cur_tag, &ts, &tl, p, 1);
469 if (Ustrcmp(cur_tag, "b") == 0)
474 where = PDKIM_HDR_VALUE;
479 if (where == PDKIM_HDR_VALUE)
481 if (c == '\r' || c == '\n' || c == ' ' || c == '\t')
484 if (c == ';' || c == '\0')
489 pdkim_strtrim(cur_val);
491 DEBUG(D_acl) debug_printf(" %s=%s\n", cur_tag, cur_val);
496 if (cur_tag[1] == 'h')
497 pdkim_decode_base64(cur_val, &sig->bodyhash);
499 pdkim_decode_base64(cur_val, &sig->sigdata);
502 /* We only support version 1, and that is currently the
503 only version there is. */
505 Ustrcmp(cur_val, PDKIM_SIGNATURE_VERSION) == 0 ? 1 : -1;
508 for (i = 0; pdkim_algos[i]; i++)
509 if (Ustrcmp(cur_val, pdkim_algos[i]) == 0)
516 for (i = 0; pdkim_combined_canons[i].str; i++)
517 if (Ustrcmp(cur_val, pdkim_combined_canons[i].str) == 0)
519 sig->canon_headers = pdkim_combined_canons[i].canon_headers;
520 sig->canon_body = pdkim_combined_canons[i].canon_body;
525 for (i = 0; pdkim_querymethods[i]; i++)
526 if (Ustrcmp(cur_val, pdkim_querymethods[i]) == 0)
528 sig->querymethod = i;
533 sig->selector = string_copy(cur_val); break;
535 sig->domain = string_copy(cur_val); break;
537 sig->identity = pdkim_decode_qp(cur_val); break;
539 sig->created = strtoul(CS cur_val, NULL, 10); break;
541 sig->expires = strtoul(CS cur_val, NULL, 10); break;
543 sig->bodylength = strtol(CS cur_val, NULL, 10); break;
545 sig->headernames = string_copy(cur_val); break;
547 sig->copiedheaders = pdkim_decode_qp(cur_val); break;
549 DEBUG(D_acl) debug_printf(" Unknown tag encountered\n");
556 where = PDKIM_HDR_LIMBO;
559 cur_val = string_catn(cur_val, &vs, &vl, p, 1);
571 /* Chomp raw header. The final newline must not be added to the signature. */
572 while (--q > sig->rawsig_no_b_val && (*q == '\r' || *q == '\n'))
578 "PDKIM >> Raw signature w/o b= tag value >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
579 pdkim_quoteprint(US sig->rawsig_no_b_val, Ustrlen(sig->rawsig_no_b_val));
581 "PDKIM >> Sig size: %4u bits\n", (unsigned) sig->sigdata.len*8);
583 "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
586 exim_sha_init(&sig->body_hash, sig->algo == PDKIM_ALGO_RSA_SHA1 ? HASH_SHA1 : HASH_SHA256);
591 /* -------------------------------------------------------------------------- */
593 static pdkim_pubkey *
594 pdkim_parse_pubkey_record(pdkim_ctx *ctx, const uschar *raw_record)
598 uschar * cur_tag = NULL; int ts = 0, tl = 0;
599 uschar * cur_val = NULL; int vs = 0, vl = 0;
600 int where = PDKIM_HDR_LIMBO;
602 pub = store_get(sizeof(pdkim_pubkey));
603 memset(pub, 0, sizeof(pdkim_pubkey));
605 for (p = raw_record; ; p++)
610 if (c != '\r' && c != '\n') switch (where)
612 case PDKIM_HDR_LIMBO: /* In limbo, just wait for a tag-char to appear */
613 if (!(c >= 'a' && c <= 'z'))
615 where = PDKIM_HDR_TAG;
619 if (c >= 'a' && c <= 'z')
620 cur_tag = string_catn(cur_tag, &ts, &tl, p, 1);
625 where = PDKIM_HDR_VALUE;
629 case PDKIM_HDR_VALUE:
630 if (c == ';' || c == '\0')
635 pdkim_strtrim(cur_val);
636 DEBUG(D_acl) debug_printf(" %s=%s\n", cur_tag, cur_val);
641 pub->version = string_copy(cur_val); break;
644 /* This field appears to never be used. Also, unclear why
645 a 'k' (key-type_ would go in this field name. There is a field
646 "keytype", also never used.
647 pub->hashes = string_copy(cur_val);
651 pub->granularity = string_copy(cur_val); break;
653 pub->notes = pdkim_decode_qp(cur_val); break;
655 pdkim_decode_base64(US cur_val, &pub->key); break;
657 pub->srvtype = string_copy(cur_val); break;
659 if (Ustrchr(cur_val, 'y') != NULL) pub->testing = 1;
660 if (Ustrchr(cur_val, 's') != NULL) pub->no_subdomaining = 1;
663 DEBUG(D_acl) debug_printf(" Unknown tag encountered\n");
669 where = PDKIM_HDR_LIMBO;
672 cur_val = string_catn(cur_val, &vs, &vl, p, 1);
676 if (c == '\0') break;
679 /* Set fallback defaults */
680 if (!pub->version ) pub->version = string_copy(PDKIM_PUB_RECORD_VERSION);
681 else if (Ustrcmp(pub->version, PDKIM_PUB_RECORD_VERSION) != 0) return NULL;
683 if (!pub->granularity) pub->granularity = string_copy(US"*");
685 if (!pub->keytype ) pub->keytype = string_copy(US"rsa");
687 if (!pub->srvtype ) pub->srvtype = string_copy(US"*");
697 /* -------------------------------------------------------------------------- */
700 pdkim_update_bodyhash(pdkim_ctx *ctx, const char *data, int len)
702 pdkim_signature *sig = ctx->sig;
703 /* Cache relaxed version of data */
704 uschar *relaxed_data = NULL;
707 /* Traverse all signatures, updating their hashes. */
710 /* Defaults to simple canon (no further treatment necessary) */
711 const uschar *canon_data = CUS data;
714 if (sig->canon_body == PDKIM_CANON_RELAXED)
716 /* Relax the line if not done already */
719 BOOL seen_wsp = FALSE;
723 /* We want to be able to free this else we allocate
724 for the entire message which could be many MB. Since
725 we don't know what allocations the SHA routines might
726 do, not safe to use store_get()/store_reset(). */
728 relaxed_data = store_malloc(len+1);
730 for (p = data; *p; p++)
735 if (q > 0 && relaxed_data[q-1] == ' ')
738 else if (c == '\t' || c == ' ')
740 c = ' '; /* Turns WSP into SP */
747 relaxed_data[q++] = c;
749 relaxed_data[q] = '\0';
752 canon_data = relaxed_data;
753 canon_len = relaxed_len;
756 /* Make sure we don't exceed the to-be-signed body length */
757 if ( sig->bodylength >= 0
758 && sig->signed_body_bytes + (unsigned long)canon_len > sig->bodylength
760 canon_len = sig->bodylength - sig->signed_body_bytes;
764 exim_sha_update(&sig->body_hash, CUS canon_data, canon_len);
765 sig->signed_body_bytes += canon_len;
766 DEBUG(D_acl) pdkim_quoteprint(canon_data, canon_len);
772 if (relaxed_data) store_free(relaxed_data);
777 /* -------------------------------------------------------------------------- */
780 pdkim_finish_bodyhash(pdkim_ctx *ctx)
782 pdkim_signature *sig;
784 /* Traverse all signatures */
785 for (sig = ctx->sig; sig; sig = sig->next)
786 { /* Finish hashes */
789 exim_sha_finish(&sig->body_hash, &bh);
793 debug_printf("PDKIM [%s] Body bytes hashed: %lu\n"
794 "PDKIM [%s] Body hash computed: ",
795 sig->domain, sig->signed_body_bytes, sig->domain);
796 pdkim_hexprint(CUS bh.data, bh.len);
799 /* SIGNING -------------------------------------------------------------- */
800 if (ctx->flags & PDKIM_MODE_SIGN)
804 /* If bodylength limit is set, and we have received less bytes
805 than the requested amount, effectively remove the limit tag. */
806 if (sig->signed_body_bytes < sig->bodylength)
807 sig->bodylength = -1;
810 /* VERIFICATION --------------------------------------------------------- */
813 /* Compare bodyhash */
814 if (memcmp(bh.data, sig->bodyhash.data, bh.len) == 0)
816 DEBUG(D_acl) debug_printf("PDKIM [%s] Body hash verified OK\n", sig->domain);
822 debug_printf("PDKIM [%s] Body hash signature from headers: ", sig->domain);
823 pdkim_hexprint(sig->bodyhash.data,
824 exim_sha_hashlen(&sig->body_hash));
825 debug_printf("PDKIM [%s] Body hash did NOT verify\n", sig->domain);
827 sig->verify_status = PDKIM_VERIFY_FAIL;
828 sig->verify_ext_status = PDKIM_VERIFY_FAIL_BODY;
837 pdkim_body_complete(pdkim_ctx * ctx)
839 pdkim_signature * sig = ctx->sig; /*XXX assumes only one sig */
841 /* In simple body mode, if any empty lines were buffered,
842 replace with one. rfc 4871 3.4.3 */
843 /*XXX checking the signed-body-bytes is a gross hack; I think
844 it indicates that all linebreaks should be buffered, including
845 the one terminating a text line */
847 if ( sig && sig->canon_body == PDKIM_CANON_SIMPLE
848 && sig->signed_body_bytes == 0
849 && ctx->num_buffered_crlf > 0
851 pdkim_update_bodyhash(ctx, "\r\n", 2);
853 ctx->flags |= PDKIM_SEEN_EOD;
854 ctx->linebuf_offset = 0;
860 /* -------------------------------------------------------------------------- */
861 /* Call from pdkim_feed below for processing complete body lines */
864 pdkim_bodyline_complete(pdkim_ctx *ctx)
866 char *p = ctx->linebuf;
867 int n = ctx->linebuf_offset;
868 pdkim_signature *sig = ctx->sig; /*XXX assumes only one sig */
870 /* Ignore extra data if we've seen the end-of-data marker */
871 if (ctx->flags & PDKIM_SEEN_EOD) goto BAIL;
873 /* We've always got one extra byte to stuff a zero ... */
874 ctx->linebuf[ctx->linebuf_offset] = '\0';
876 /* Terminate on EOD marker */
877 if (ctx->flags & PDKIM_DOT_TERM)
879 if (memcmp(p, ".\r\n", 3) == 0)
880 return pdkim_body_complete(ctx);
883 if (memcmp(p, "..", 2) == 0)
890 /* Empty lines need to be buffered until we find a non-empty line */
891 if (memcmp(p, "\r\n", 2) == 0)
893 ctx->num_buffered_crlf++;
897 if (sig && sig->canon_body == PDKIM_CANON_RELAXED)
899 /* Lines with just spaces need to be buffered too */
901 while (memcmp(check, "\r\n", 2) != 0)
905 if (c != '\t' && c != ' ')
910 ctx->num_buffered_crlf++;
915 /* At this point, we have a non-empty line, so release the buffered ones. */
916 while (ctx->num_buffered_crlf)
918 pdkim_update_bodyhash(ctx, "\r\n", 2);
919 ctx->num_buffered_crlf--;
922 pdkim_update_bodyhash(ctx, p, n);
925 ctx->linebuf_offset = 0;
930 /* -------------------------------------------------------------------------- */
931 /* Callback from pdkim_feed below for processing complete headers */
932 #define DKIM_SIGNATURE_HEADERNAME "DKIM-Signature:"
935 pdkim_header_complete(pdkim_ctx *ctx)
937 /* Special case: The last header can have an extra \r appended */
938 if ( (ctx->cur_header_len > 1) &&
939 (ctx->cur_header[(ctx->cur_header_len)-1] == '\r') )
940 --ctx->cur_header_len;
941 ctx->cur_header[ctx->cur_header_len] = '\0';
944 if (ctx->num_headers > PDKIM_MAX_HEADERS) goto BAIL;
946 /* SIGNING -------------------------------------------------------------- */
947 if (ctx->flags & PDKIM_MODE_SIGN)
949 pdkim_signature *sig;
951 for (sig = ctx->sig; sig; sig = sig->next) /* Traverse all signatures */
953 /* Add header to the signed headers list (in reverse order) */
954 sig->headers = pdkim_prepend_stringlist(sig->headers,
958 /* VERIFICATION ----------------------------------------------------------- */
959 /* DKIM-Signature: headers are added to the verification list */
964 debug_printf("PDKIM >> raw hdr: ");
965 pdkim_quoteprint(CUS ctx->cur_header, Ustrlen(ctx->cur_header));
967 if (strncasecmp(CCS ctx->cur_header,
968 DKIM_SIGNATURE_HEADERNAME,
969 Ustrlen(DKIM_SIGNATURE_HEADERNAME)) == 0)
971 pdkim_signature *new_sig;
973 /* Create and chain new signature block */
974 DEBUG(D_acl) debug_printf(
975 "PDKIM >> Found sig, trying to parse >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
977 if ((new_sig = pdkim_parse_sig_header(ctx, ctx->cur_header)))
979 pdkim_signature *last_sig = ctx->sig;
984 while (last_sig->next) last_sig = last_sig->next;
985 last_sig->next = new_sig;
989 DEBUG(D_acl) debug_printf(
990 "Error while parsing signature header\n"
991 "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
994 /* all headers are stored for signature verification */
995 ctx->headers = pdkim_prepend_stringlist(ctx->headers, ctx->cur_header);
999 *ctx->cur_header = '\0';
1000 ctx->cur_header_len = 0; /* leave buffer for reuse */
1006 /* -------------------------------------------------------------------------- */
1007 #define HEADER_BUFFER_FRAG_SIZE 256
1010 pdkim_feed(pdkim_ctx *ctx, char *data, int len)
1014 /* Alternate EOD signal, used in non-dotstuffing mode */
1016 pdkim_body_complete(ctx);
1018 else for (p = 0; p<len; p++)
1022 if (ctx->flags & PDKIM_PAST_HDRS)
1024 if (c == '\n' && !(ctx->flags & PDKIM_SEEN_CR)) /* emulate the CR */
1026 ctx->linebuf[ctx->linebuf_offset++] = '\r';
1027 if (ctx->linebuf_offset == PDKIM_MAX_BODY_LINE_LEN-1)
1028 return PDKIM_ERR_LONG_LINE;
1031 /* Processing body byte */
1032 ctx->linebuf[ctx->linebuf_offset++] = c;
1034 ctx->flags |= PDKIM_SEEN_CR;
1038 ctx->flags &= ~PDKIM_SEEN_CR;
1039 if ((rc = pdkim_bodyline_complete(ctx)) != PDKIM_OK)
1043 if (ctx->linebuf_offset == PDKIM_MAX_BODY_LINE_LEN-1)
1044 return PDKIM_ERR_LONG_LINE;
1048 /* Processing header byte */
1050 ctx->flags |= PDKIM_SEEN_CR;
1053 if (!(ctx->flags & PDKIM_SEEN_CR)) /* emulate the CR */
1054 ctx->cur_header = string_catn(ctx->cur_header, &ctx->cur_header_size,
1055 &ctx->cur_header_len, CUS "\r", 1);
1057 if (ctx->flags & PDKIM_SEEN_LF)
1059 int rc = pdkim_header_complete(ctx); /* Seen last header line */
1060 if (rc != PDKIM_OK) return rc;
1062 ctx->flags = ctx->flags & ~(PDKIM_SEEN_LF|PDKIM_SEEN_CR) | PDKIM_PAST_HDRS;
1063 DEBUG(D_acl) debug_printf(
1064 "PDKIM >> Body data for hash, canonicalized >>>>>>>>>>>>>>>>>>>>>>\n");
1068 ctx->flags = ctx->flags & ~PDKIM_SEEN_CR | PDKIM_SEEN_LF;
1070 else if (ctx->flags & PDKIM_SEEN_LF)
1072 if (!(c == '\t' || c == ' '))
1074 int rc = pdkim_header_complete(ctx); /* End of header */
1075 if (rc != PDKIM_OK) return rc;
1077 ctx->flags &= ~PDKIM_SEEN_LF;
1080 if (ctx->cur_header_len < PDKIM_MAX_HEADER_LEN)
1081 ctx->cur_header = string_catn(ctx->cur_header, &ctx->cur_header_size,
1082 &ctx->cur_header_len, CUS &data[p], 1);
1090 /* Extend a grwong header with a continuation-linebreak */
1092 pdkim_hdr_cont(uschar * str, int * size, int * ptr, int * col)
1095 return string_catn(str, size, ptr, US"\r\n\t", 3);
1101 * RFC 5322 specifies that header line length SHOULD be no more than 78
1105 * returns uschar * (not nul-terminated)
1107 * col: this int holds and receives column number (octets since last '\n')
1108 * str: partial string to append to
1109 * size: current buffer size for str
1110 * ptr: current tail-pointer for str
1111 * pad: padding, split line or space after before or after eg: ";"
1112 * intro: - must join to payload eg "h=", usually the tag name
1113 * payload: eg base64 data - long data can be split arbitrarily.
1115 * this code doesn't fold the header in some of the places that RFC4871
1116 * allows: As per RFC5322(2.2.3) it only folds before or after tag-value
1117 * pairs and inside long values. it also always spaces or breaks after the
1120 * no guarantees are made for output given out-of range input. like tag
1121 * names longer than 78, or bogus col. Input is assumed to be free of line breaks.
1125 pdkim_headcat(int * col, uschar * str, int * size, int * ptr,
1126 const uschar * pad, const uschar * intro, const uschar * payload)
1134 str = pdkim_hdr_cont(str, size, ptr, col);
1135 str = string_catn(str, size, ptr, pad, l);
1139 l = (pad?1:0) + (intro?Ustrlen(intro):0);
1142 { /*can't fit intro - start a new line to make room.*/
1143 str = pdkim_hdr_cont(str, size, ptr, col);
1144 l = intro?Ustrlen(intro):0;
1147 l += payload ? Ustrlen(payload):0 ;
1150 { /* this fragment will not fit on a single line */
1153 str = string_catn(str, size, ptr, US" ", 1);
1155 pad = NULL; /* only want this once */
1161 size_t sl = Ustrlen(intro);
1163 str = string_catn(str, size, ptr, intro, sl);
1166 intro = NULL; /* only want this once */
1171 size_t sl = Ustrlen(payload);
1172 size_t chomp = *col+sl < 77 ? sl : 78-*col;
1174 str = string_catn(str, size, ptr, payload, chomp);
1180 /* the while precondition tells us it didn't fit. */
1181 str = pdkim_hdr_cont(str, size, ptr, col);
1186 str = pdkim_hdr_cont(str, size, ptr, col);
1192 str = string_catn(str, size, ptr, US" ", 1);
1199 size_t sl = Ustrlen(intro);
1201 str = string_catn(str, size, ptr, intro, sl);
1209 size_t sl = Ustrlen(payload);
1211 str = string_catn(str, size, ptr, payload, sl);
1219 /* -------------------------------------------------------------------------- */
1222 pdkim_create_header(pdkim_signature *sig, BOOL final)
1227 uschar * hdr; int hdr_size = 0, hdr_len = 0;
1228 uschar * canon_all; int can_size = 0, can_len = 0;
1230 canon_all = string_cat (NULL, &can_size, &can_len,
1231 pdkim_canons[sig->canon_headers]);
1232 canon_all = string_catn(canon_all, &can_size, &can_len, US"/", 1);
1233 canon_all = string_cat (canon_all, &can_size, &can_len,
1234 pdkim_canons[sig->canon_body]);
1235 canon_all[can_len] = '\0';
1237 hdr = string_cat(NULL, &hdr_size, &hdr_len,
1238 US"DKIM-Signature: v="PDKIM_SIGNATURE_VERSION);
1241 /* Required and static bits */
1242 hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"a=",
1243 pdkim_algos[sig->algo]);
1244 hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"q=",
1245 pdkim_querymethods[sig->querymethod]);
1246 hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"c=",
1248 hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"d=",
1250 hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"s=",
1253 /* list of header names can be split between items. */
1255 uschar * n = string_copy(sig->headernames);
1256 uschar * i = US"h=";
1261 uschar * c = Ustrchr(n, ':');
1266 hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, NULL, NULL, US":");
1268 hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, s, i, n);
1279 base64_bh = pdkim_encode_base64(&sig->bodyhash);
1280 hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"bh=", base64_bh);
1284 hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"i=", sig->identity);
1286 if (sig->created > 0)
1290 snprintf(CS minibuf, sizeof(minibuf), "%lu", sig->created);
1291 hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"t=", minibuf);
1294 if (sig->expires > 0)
1298 snprintf(CS minibuf, sizeof(minibuf), "%lu", sig->expires);
1299 hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"x=", minibuf);
1302 if (sig->bodylength >= 0)
1306 snprintf(CS minibuf, sizeof(minibuf), "%lu", sig->bodylength);
1307 hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"l=", minibuf);
1310 /* Preliminary or final version? */
1311 base64_b = final ? pdkim_encode_base64(&sig->sigdata) : US"";
1312 hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"b=", base64_b);
1314 /* add trailing semicolon: I'm not sure if this is actually needed */
1315 hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, NULL, US";", US"");
1317 hdr[hdr_len] = '\0';
1322 /* -------------------------------------------------------------------------- */
1324 static pdkim_pubkey *
1325 pdkim_key_from_dns(pdkim_ctx * ctx, pdkim_signature * sig, ev_ctx * vctx)
1327 uschar * dns_txt_name, * dns_txt_reply;
1329 const uschar * errstr;
1331 /* Fetch public key for signing domain, from DNS */
1333 dns_txt_name = string_sprintf("%s._domainkey.%s.", sig->selector, sig->domain);
1335 dns_txt_reply = store_get(PDKIM_DNS_TXT_MAX_RECLEN);
1336 memset(dns_txt_reply, 0, PDKIM_DNS_TXT_MAX_RECLEN);
1338 if ( ctx->dns_txt_callback(CS dns_txt_name, CS dns_txt_reply) != PDKIM_OK
1339 || dns_txt_reply[0] == '\0'
1342 sig->verify_status = PDKIM_VERIFY_INVALID;
1343 sig->verify_ext_status = PDKIM_VERIFY_INVALID_PUBKEY_UNAVAILABLE;
1350 "PDKIM >> Parsing public key record >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n"
1352 pdkim_quoteprint(CUS dns_txt_reply, Ustrlen(dns_txt_reply));
1355 if ( !(p = pdkim_parse_pubkey_record(ctx, CUS dns_txt_reply))
1356 || (Ustrcmp(p->srvtype, "*") != 0 && Ustrcmp(p->srvtype, "email") != 0)
1359 sig->verify_status = PDKIM_VERIFY_INVALID;
1360 sig->verify_ext_status = PDKIM_VERIFY_INVALID_PUBKEY_DNSRECORD;
1365 debug_printf(" Invalid public key service type '%s'\n", p->srvtype);
1367 debug_printf(" Error while parsing public key record\n");
1369 "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
1374 DEBUG(D_acl) debug_printf(
1375 "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
1377 /* Import public key */
1378 if ((errstr = exim_rsa_verify_init(&p->key, vctx)))
1380 DEBUG(D_acl) debug_printf("verify_init: %s\n", errstr);
1381 sig->verify_status = PDKIM_VERIFY_INVALID;
1382 sig->verify_ext_status = PDKIM_VERIFY_INVALID_PUBKEY_IMPORT;
1390 /* -------------------------------------------------------------------------- */
1393 pdkim_feed_finish(pdkim_ctx *ctx, pdkim_signature **return_signatures)
1395 pdkim_signature *sig = ctx->sig;
1397 /* Check if we must still flush a (partial) header. If that is the
1398 case, the message has no body, and we must compute a body hash
1399 out of '<CR><LF>' */
1400 if (ctx->cur_header && ctx->cur_header_len)
1402 int rc = pdkim_header_complete(ctx);
1403 if (rc != PDKIM_OK) return rc;
1404 pdkim_update_bodyhash(ctx, "\r\n", 2);
1407 DEBUG(D_acl) debug_printf(
1408 "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
1410 /* Build (and/or evaluate) body hash */
1411 pdkim_finish_bodyhash(ctx);
1415 BOOL is_sha1 = sig->algo == PDKIM_ALGO_RSA_SHA1;
1417 uschar * sig_hdr = US"";
1420 int hdata_alloc = 0;
1425 exim_sha_init(&hhash_ctx, is_sha1 ? HASH_SHA1 : HASH_SHA256);
1427 DEBUG(D_acl) debug_printf(
1428 "PDKIM >> Header data for hash, canonicalized, in sequence >>>>>>>>>>>>>>\n");
1430 /* SIGNING ---------------------------------------------------------------- */
1431 /* When signing, walk through our header list and add them to the hash. As we
1432 go, construct a list of the header's names to use for the h= parameter.
1433 Then append to that list any remaining header names for which there was no
1436 if (ctx->flags & PDKIM_MODE_SIGN)
1438 uschar * headernames = NULL; /* Collected signed header names */
1440 pdkim_stringlist *p;
1445 for (p = sig->headers; p; p = p->next)
1446 if (header_name_match(p->value, sig->sign_headers) == PDKIM_OK)
1449 /* Collect header names (Note: colon presence is guaranteed here) */
1450 uschar * q = Ustrchr(p->value, ':');
1452 headernames = string_catn(headernames, &hs, &hl,
1453 p->value, (q - US p->value) + (p->next ? 1 : 0));
1455 rh = sig->canon_headers == PDKIM_CANON_RELAXED
1456 ? pdkim_relax_header(p->value, 1) /* cook header for relaxed canon */
1457 : string_copy(CUS p->value); /* just copy it for simple canon */
1459 /* Feed header to the hash algorithm */
1460 exim_sha_update(&hhash_ctx, CUS rh, Ustrlen(rh));
1462 /* Remember headers block for signing (when the library cannot do incremental) */
1463 (void) exim_rsa_data_append(&hdata, &hdata_alloc, rh);
1465 DEBUG(D_acl) pdkim_quoteprint(rh, Ustrlen(rh));
1468 l = sig->sign_headers;
1469 while((s = string_nextinlist(&l, &sep, NULL, 0)))
1471 { /*SSS string_append_listele() */
1472 if (hl > 0 && headernames[hl-1] != ':')
1473 headernames = string_catn(headernames, &hs, &hl, US":", 1);
1475 headernames = string_cat(headernames, &hs, &hl, s);
1477 headernames[hl] = '\0';
1479 /* Copy headernames to signature struct */
1480 sig->headernames = headernames;
1482 /* Create signature header with b= omitted */
1483 sig_hdr = pdkim_create_header(sig, FALSE);
1486 /* VERIFICATION ----------------------------------------------------------- */
1487 /* When verifying, walk through the header name list in the h= parameter and
1488 add the headers to the hash in that order. */
1491 uschar * p = sig->headernames;
1493 pdkim_stringlist * hdrs;
1498 for (hdrs = ctx->headers; hdrs; hdrs = hdrs->next)
1504 if ((q = Ustrchr(p, ':')))
1507 /*XXX walk the list of headers in same order as received. */
1508 for (hdrs = ctx->headers; hdrs; hdrs = hdrs->next)
1510 && strncasecmp(CCS hdrs->value, CCS p, Ustrlen(p)) == 0
1511 && (hdrs->value)[Ustrlen(p)] == ':'
1514 /* cook header for relaxed canon, or just copy it for simple */
1516 uschar * rh = sig->canon_headers == PDKIM_CANON_RELAXED
1517 ? pdkim_relax_header(hdrs->value, 1)
1518 : string_copy(CUS hdrs->value);
1520 /* Feed header to the hash algorithm */
1521 exim_sha_update(&hhash_ctx, CUS rh, Ustrlen(rh));
1523 DEBUG(D_acl) pdkim_quoteprint(rh, Ustrlen(rh));
1532 sig_hdr = string_copy(sig->rawsig_no_b_val);
1536 DEBUG(D_acl) debug_printf(
1537 "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
1539 /* Relax header if necessary */
1540 if (sig->canon_headers == PDKIM_CANON_RELAXED)
1541 sig_hdr = pdkim_relax_header(sig_hdr, 0);
1546 "PDKIM >> Signed DKIM-Signature header, canonicalized >>>>>>>>>>>>>>>>>\n");
1547 pdkim_quoteprint(CUS sig_hdr, Ustrlen(sig_hdr));
1549 "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
1552 /* Finalize header hash */
1553 exim_sha_update(&hhash_ctx, CUS sig_hdr, Ustrlen(sig_hdr));
1554 exim_sha_finish(&hhash_ctx, &hhash);
1558 debug_printf("PDKIM [%s] Header hash computed: ", sig->domain);
1559 pdkim_hexprint(hhash.data, hhash.len);
1562 /* Remember headers block for signing (when the library cannot do incremental) */
1563 if (ctx->flags & PDKIM_MODE_SIGN)
1564 (void) exim_rsa_data_append(&hdata, &hdata_alloc, US sig_hdr);
1566 /* SIGNING ---------------------------------------------------------------- */
1567 if (ctx->flags & PDKIM_MODE_SIGN)
1570 const uschar * errstr;
1572 /* Import private key */
1573 if ((errstr = exim_rsa_signing_init(US sig->rsa_privkey, &sctx)))
1575 DEBUG(D_acl) debug_printf("signing_init: %s\n", errstr);
1576 return PDKIM_ERR_RSA_PRIVKEY;
1579 /* Do signing. With OpenSSL we are signing the hash of headers just
1580 calculated, with GnuTLS we have to sign an entire block of headers
1581 (due to available interfaces) and it recalculates the hash internally. */
1583 #if defined(RSA_OPENSSL) || defined(RSA_GCRYPT)
1587 if ((errstr = exim_rsa_sign(&sctx, is_sha1, &hdata, &sig->sigdata)))
1589 DEBUG(D_acl) debug_printf("signing: %s\n", errstr);
1590 return PDKIM_ERR_RSA_SIGNING;
1595 debug_printf( "PDKIM [%s] b computed: ", sig->domain);
1596 pdkim_hexprint(sig->sigdata.data, sig->sigdata.len);
1599 sig->signature_header = pdkim_create_header(sig, TRUE);
1602 /* VERIFICATION ----------------------------------------------------------- */
1606 const uschar * errstr;
1609 /* Make sure we have all required signature tags */
1610 if (!( sig->domain && *sig->domain
1611 && sig->selector && *sig->selector
1612 && sig->headernames && *sig->headernames
1613 && sig->bodyhash.data
1614 && sig->sigdata.data
1619 sig->verify_status = PDKIM_VERIFY_INVALID;
1620 sig->verify_ext_status = PDKIM_VERIFY_INVALID_SIGNATURE_ERROR;
1622 DEBUG(D_acl) debug_printf(
1623 " Error in DKIM-Signature header: tags missing or invalid\n"
1624 "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
1628 /* Make sure sig uses supported DKIM version (only v1) */
1629 if (sig->version != 1)
1631 sig->verify_status = PDKIM_VERIFY_INVALID;
1632 sig->verify_ext_status = PDKIM_VERIFY_INVALID_DKIM_VERSION;
1634 DEBUG(D_acl) debug_printf(
1635 " Error in DKIM-Signature header: unsupported DKIM version\n"
1636 "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
1640 if (!(sig->pubkey = pdkim_key_from_dns(ctx, sig, &vctx)))
1643 /* Check the signature */
1644 if ((errstr = exim_rsa_verify(&vctx, is_sha1, &hhash, &sig->sigdata)))
1646 DEBUG(D_acl) debug_printf("headers verify: %s\n", errstr);
1647 sig->verify_status = PDKIM_VERIFY_FAIL;
1648 sig->verify_ext_status = PDKIM_VERIFY_FAIL_MESSAGE;
1653 /* We have a winner! (if bodyhash was correct earlier) */
1654 if (sig->verify_status == PDKIM_VERIFY_NONE)
1655 sig->verify_status = PDKIM_VERIFY_PASS;
1661 debug_printf("PDKIM [%s] signature status: %s",
1662 sig->domain, pdkim_verify_status_str(sig->verify_status));
1663 if (sig->verify_ext_status > 0)
1664 debug_printf(" (%s)\n",
1665 pdkim_verify_ext_status_str(sig->verify_ext_status));
1674 /* If requested, set return pointer to signature(s) */
1675 if (return_signatures)
1676 *return_signatures = ctx->sig;
1682 /* -------------------------------------------------------------------------- */
1684 DLLEXPORT pdkim_ctx *
1685 pdkim_init_verify(int(*dns_txt_callback)(char *, char *), BOOL dot_stuffing)
1689 ctx = store_get(sizeof(pdkim_ctx));
1690 memset(ctx, 0, sizeof(pdkim_ctx));
1692 if (dot_stuffing) ctx->flags = PDKIM_DOT_TERM;
1693 ctx->linebuf = store_get(PDKIM_MAX_BODY_LINE_LEN);
1694 ctx->dns_txt_callback = dns_txt_callback;
1700 /* -------------------------------------------------------------------------- */
1702 DLLEXPORT pdkim_ctx *
1703 pdkim_init_sign(char * domain, char * selector, char * rsa_privkey, int algo,
1704 BOOL dot_stuffed, int(*dns_txt_callback)(char *, char *))
1707 pdkim_signature * sig;
1709 if (!domain || !selector || !rsa_privkey)
1712 ctx = store_get(sizeof(pdkim_ctx) + PDKIM_MAX_BODY_LINE_LEN + sizeof(pdkim_signature));
1713 memset(ctx, 0, sizeof(pdkim_ctx));
1715 ctx->flags = dot_stuffed ? PDKIM_MODE_SIGN | PDKIM_DOT_TERM : PDKIM_MODE_SIGN;
1716 ctx->linebuf = CS (ctx+1);
1718 DEBUG(D_acl) ctx->dns_txt_callback = dns_txt_callback;
1720 sig = (pdkim_signature *)(ctx->linebuf + PDKIM_MAX_BODY_LINE_LEN);
1721 memset(sig, 0, sizeof(pdkim_signature));
1723 sig->bodylength = -1;
1726 sig->domain = string_copy(US domain);
1727 sig->selector = string_copy(US selector);
1728 sig->rsa_privkey = string_copy(US rsa_privkey);
1731 exim_sha_init(&sig->body_hash, algo == PDKIM_ALGO_RSA_SHA1 ? HASH_SHA1 : HASH_SHA256);
1735 pdkim_signature s = *sig;
1738 debug_printf("PDKIM (checking verify key)<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
1739 if (!pdkim_key_from_dns(ctx, &s, &vctx))
1740 debug_printf("WARNING: bad dkim key in dns\n");
1741 debug_printf("PDKIM (finished checking verify key)<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
1748 /* -------------------------------------------------------------------------- */
1751 pdkim_set_optional(pdkim_ctx *ctx,
1757 unsigned long created,
1758 unsigned long expires)
1760 pdkim_signature * sig = ctx->sig;
1763 sig->identity = string_copy(US identity);
1765 sig->sign_headers = string_copy(sign_headers
1766 ? US sign_headers : US PDKIM_DEFAULT_SIGN_HEADERS);
1768 sig->canon_headers = canon_headers;
1769 sig->canon_body = canon_body;
1770 sig->bodylength = bodylength;
1771 sig->created = created;
1772 sig->expires = expires;
1786 #endif /*DISABLE_DKIM*/