X-Git-Url: https://git.exim.org/exim.git/blobdiff_plain/4dc2379ac1ab6c21f265abed06dd9aaa214976af..HEAD:/src/src/pdkim/pdkim.c diff --git a/src/src/pdkim/pdkim.c b/src/src/pdkim/pdkim.c deleted file mode 100644 index 7bfcdf4aa..000000000 --- a/src/src/pdkim/pdkim.c +++ /dev/null @@ -1,1733 +0,0 @@ -/* - * PDKIM - a RFC4871 (DKIM) implementation - * - * Copyright (C) 2009 - 2016 Tom Kistner - * Copyright (C) 2016 Jeremy Harris - * - * http://duncanthrax.net/pdkim/ - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License along - * with this program; if not, write to the Free Software Foundation, Inc., - * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. - */ - -#include "../exim.h" - - -#ifndef DISABLE_DKIM /* entire file */ - -#ifndef SUPPORT_TLS -# error Need SUPPORT_TLS for DKIM -#endif - -#include "crypt_ver.h" - -#ifdef RSA_OPENSSL -# include -# include -# include -#elif defined(RSA_GNUTLS) -# include -# include -#endif - -#include "pdkim.h" -#include "rsa.h" - -#define PDKIM_SIGNATURE_VERSION "1" -#define PDKIM_PUB_RECORD_VERSION US "DKIM1" - -#define PDKIM_MAX_HEADER_LEN 65536 -#define PDKIM_MAX_HEADERS 512 -#define PDKIM_MAX_BODY_LINE_LEN 16384 -#define PDKIM_DNS_TXT_MAX_NAMELEN 1024 -#define PDKIM_DEFAULT_SIGN_HEADERS "From:Sender:Reply-To:Subject:Date:"\ - "Message-ID:To:Cc:MIME-Version:Content-Type:"\ - "Content-Transfer-Encoding:Content-ID:"\ - "Content-Description:Resent-Date:Resent-From:"\ - "Resent-Sender:Resent-To:Resent-Cc:"\ - "Resent-Message-ID:In-Reply-To:References:"\ - "List-Id:List-Help:List-Unsubscribe:"\ - "List-Subscribe:List-Post:List-Owner:List-Archive" - -/* -------------------------------------------------------------------------- */ -struct pdkim_stringlist { - uschar * value; - int tag; - void * next; -}; - -/* -------------------------------------------------------------------------- */ -/* A bunch of list constants */ -const uschar * pdkim_querymethods[] = { - US"dns/txt", - NULL -}; -const uschar * pdkim_algos[] = { - US"rsa-sha256", - US"rsa-sha1", - NULL -}; -const uschar * pdkim_canons[] = { - US"simple", - US"relaxed", - NULL -}; -const uschar * pdkim_hashes[] = { - US"sha256", - US"sha1", - NULL -}; -const uschar * pdkim_keytypes[] = { - US"rsa", - NULL -}; - -typedef struct pdkim_combined_canon_entry { - const uschar * str; - int canon_headers; - int canon_body; -} pdkim_combined_canon_entry; - -pdkim_combined_canon_entry pdkim_combined_canons[] = { - { US"simple/simple", PDKIM_CANON_SIMPLE, PDKIM_CANON_SIMPLE }, - { US"simple/relaxed", PDKIM_CANON_SIMPLE, PDKIM_CANON_RELAXED }, - { US"relaxed/simple", PDKIM_CANON_RELAXED, PDKIM_CANON_SIMPLE }, - { US"relaxed/relaxed", PDKIM_CANON_RELAXED, PDKIM_CANON_RELAXED }, - { US"simple", PDKIM_CANON_SIMPLE, PDKIM_CANON_SIMPLE }, - { US"relaxed", PDKIM_CANON_RELAXED, PDKIM_CANON_SIMPLE }, - { NULL, 0, 0 } -}; - - -/* -------------------------------------------------------------------------- */ - -const char * -pdkim_verify_status_str(int status) -{ -switch(status) - { - case PDKIM_VERIFY_NONE: return "PDKIM_VERIFY_NONE"; - case PDKIM_VERIFY_INVALID: return "PDKIM_VERIFY_INVALID"; - case PDKIM_VERIFY_FAIL: return "PDKIM_VERIFY_FAIL"; - case PDKIM_VERIFY_PASS: return "PDKIM_VERIFY_PASS"; - default: return "PDKIM_VERIFY_UNKNOWN"; - } -} - -const char * -pdkim_verify_ext_status_str(int ext_status) -{ -switch(ext_status) - { - case PDKIM_VERIFY_FAIL_BODY: return "PDKIM_VERIFY_FAIL_BODY"; - case PDKIM_VERIFY_FAIL_MESSAGE: return "PDKIM_VERIFY_FAIL_MESSAGE"; - case PDKIM_VERIFY_INVALID_PUBKEY_UNAVAILABLE: return "PDKIM_VERIFY_INVALID_PUBKEY_UNAVAILABLE"; - case PDKIM_VERIFY_INVALID_BUFFER_SIZE: return "PDKIM_VERIFY_INVALID_BUFFER_SIZE"; - case PDKIM_VERIFY_INVALID_PUBKEY_DNSRECORD: return "PDKIM_VERIFY_INVALID_PUBKEY_DNSRECORD"; - case PDKIM_VERIFY_INVALID_PUBKEY_IMPORT: return "PDKIM_VERIFY_INVALID_PUBKEY_IMPORT"; - case PDKIM_VERIFY_INVALID_SIGNATURE_ERROR: return "PDKIM_VERIFY_INVALID_SIGNATURE_ERROR"; - case PDKIM_VERIFY_INVALID_DKIM_VERSION: return "PDKIM_VERIFY_INVALID_DKIM_VERSION"; - default: return "PDKIM_VERIFY_UNKNOWN"; - } -} - -const char * -pdkim_errstr(int status) -{ -switch(status) - { - case PDKIM_OK: return "OK"; - case PDKIM_FAIL: return "FAIL"; - case PDKIM_ERR_RSA_PRIVKEY: return "RSA_PRIVKEY"; - case PDKIM_ERR_RSA_SIGNING: return "RSA SIGNING"; - case PDKIM_ERR_LONG_LINE: return "RSA_LONG_LINE"; - case PDKIM_ERR_BUFFER_TOO_SMALL: return "BUFFER_TOO_SMALL"; - case PDKIM_SIGN_PRIVKEY_WRAP: return "PRIVKEY_WRAP"; - case PDKIM_SIGN_PRIVKEY_B64D: return "PRIVKEY_B64D"; - default: return "(unknown)"; - } -} - - -/* -------------------------------------------------------------------------- */ -/* Print debugging functions */ -static void -pdkim_quoteprint(const uschar *data, int len) -{ -int i; -for (i = 0; i < len; i++) - { - const int c = data[i]; - switch (c) - { - case ' ' : debug_printf("{SP}"); break; - case '\t': debug_printf("{TB}"); break; - case '\r': debug_printf("{CR}"); break; - case '\n': debug_printf("{LF}"); break; - case '{' : debug_printf("{BO}"); break; - case '}' : debug_printf("{BC}"); break; - default: - if ( (c < 32) || (c > 127) ) - debug_printf("{%02x}", c); - else - debug_printf("%c", c); - break; - } - } -debug_printf("\n"); -} - -static void -pdkim_hexprint(const uschar *data, int len) -{ -int i; -for (i = 0 ; i < len; i++) debug_printf("%02x", data[i]); -debug_printf("\n"); -} - - - -static pdkim_stringlist * -pdkim_prepend_stringlist(pdkim_stringlist * base, const uschar * str) -{ -pdkim_stringlist * new_entry = store_get(sizeof(pdkim_stringlist)); - -memset(new_entry, 0, sizeof(pdkim_stringlist)); -new_entry->value = string_copy(str); -if (base) new_entry->next = base; -return new_entry; -} - - - -/* Trim whitespace fore & aft */ - -static void -pdkim_strtrim(uschar * str) -{ -uschar * p = str; -uschar * q = str; -while (*p == '\t' || *p == ' ') p++; /* skip whitespace */ -while (*p) {*q = *p; q++; p++;} /* dump the leading whitespace */ -*q = '\0'; -while (q != str && ( (*q == '\0') || (*q == '\t') || (*q == ' ') ) ) - { /* dump trailing whitespace */ - *q = '\0'; - q--; - } -} - - - -/* -------------------------------------------------------------------------- */ - -DLLEXPORT void -pdkim_free_ctx(pdkim_ctx *ctx) -{ -} - - -/* -------------------------------------------------------------------------- */ -/* Matches the name of the passed raw "header" against - the passed colon-separated "tick", and invalidates - the entry in tick. Returns OK or fail-code */ -/*XXX might be safer done using a pdkim_stringlist for "tick" */ - -static int -header_name_match(const uschar * header, uschar * tick) -{ -uschar * hname; -uschar * lcopy; -uschar * p; -uschar * q; -uschar * hcolon = Ustrchr(header, ':'); /* Get header name */ - -if (!hcolon) - return PDKIM_FAIL; /* This isn't a header */ - -/* if we had strncmpic() we wouldn't need this copy */ -hname = string_copyn(header, hcolon-header); - -/* Copy tick-off list locally, so we can punch zeroes into it */ -p = lcopy = string_copy(tick); - -for (q = Ustrchr(p, ':'); q; q = Ustrchr(p, ':')) - { - *q = '\0'; - if (strcmpic(p, hname) == 0) - goto found; - - p = q+1; - } - -if (strcmpic(p, hname) == 0) - goto found; - -return PDKIM_FAIL; - -found: - /* Invalidate header name instance in tick-off list */ - tick[p-lcopy] = '_'; - return PDKIM_OK; -} - - -/* -------------------------------------------------------------------------- */ -/* Performs "relaxed" canonicalization of a header. */ - -static uschar * -pdkim_relax_header(const uschar * header, int crlf) -{ -BOOL past_field_name = FALSE; -BOOL seen_wsp = FALSE; -const uschar * p; -uschar * relaxed = store_get(Ustrlen(header)+3); -uschar * q = relaxed; - -for (p = header; *p; p++) - { - uschar c = *p; - /* Ignore CR & LF */ - if (c == '\r' || c == '\n') - continue; - if (c == '\t' || c == ' ') - { - if (seen_wsp) - continue; - c = ' '; /* Turns WSP into SP */ - seen_wsp = TRUE; - } - else - if (!past_field_name && c == ':') - { - if (seen_wsp) q--; /* This removes WSP before the colon */ - seen_wsp = TRUE; /* This removes WSP after the colon */ - past_field_name = TRUE; - } - else - seen_wsp = FALSE; - - /* Lowercase header name */ - if (!past_field_name) c = tolower(c); - *q++ = c; - } - -if (q > relaxed && q[-1] == ' ') q--; /* Squash eventual trailing SP */ - -if (crlf) { *q++ = '\r'; *q++ = '\n'; } -*q = '\0'; -return relaxed; -} - - -/* -------------------------------------------------------------------------- */ -#define PDKIM_QP_ERROR_DECODE -1 - -static uschar * -pdkim_decode_qp_char(uschar *qp_p, int *c) -{ -uschar *initial_pos = qp_p; - -/* Advance one char */ -qp_p++; - -/* Check for two hex digits and decode them */ -if (isxdigit(*qp_p) && isxdigit(qp_p[1])) - { - /* Do hex conversion */ - *c = (isdigit(*qp_p) ? *qp_p - '0' : toupper(*qp_p) - 'A' + 10) << 4; - *c |= isdigit(qp_p[1]) ? qp_p[1] - '0' : toupper(qp_p[1]) - 'A' + 10; - return qp_p + 2; - } - -/* Illegal char here */ -*c = PDKIM_QP_ERROR_DECODE; -return initial_pos; -} - - -/* -------------------------------------------------------------------------- */ - -static uschar * -pdkim_decode_qp(uschar * str) -{ -int nchar = 0; -uschar * q; -uschar * p = str; -uschar * n = store_get(Ustrlen(str)+1); - -*n = '\0'; -q = n; -while (*p) - { - if (*p == '=') - { - p = pdkim_decode_qp_char(p, &nchar); - if (nchar >= 0) - { - *q++ = nchar; - continue; - } - } - else - *q++ = *p; - p++; - } -*q = '\0'; -return n; -} - - -/* -------------------------------------------------------------------------- */ - -static void -pdkim_decode_base64(uschar *str, blob * b) -{ -int dlen; -dlen = b64decode(str, &b->data); -if (dlen < 0) b->data = NULL; -b->len = dlen; -} - -static uschar * -pdkim_encode_base64(blob * b) -{ -return b64encode(b->data, b->len); -} - - -/* -------------------------------------------------------------------------- */ -#define PDKIM_HDR_LIMBO 0 -#define PDKIM_HDR_TAG 1 -#define PDKIM_HDR_VALUE 2 - -static pdkim_signature * -pdkim_parse_sig_header(pdkim_ctx *ctx, uschar * raw_hdr) -{ -pdkim_signature *sig ; -uschar *p, *q; -uschar * cur_tag = NULL; int ts = 0, tl = 0; -uschar * cur_val = NULL; int vs = 0, vl = 0; -BOOL past_hname = FALSE; -BOOL in_b_val = FALSE; -int where = PDKIM_HDR_LIMBO; -int i; - -sig = store_get(sizeof(pdkim_signature)); -memset(sig, 0, sizeof(pdkim_signature)); -sig->bodylength = -1; - -/* Set so invalid/missing data error display is accurate */ -sig->algo = -1; -sig->version = 0; - -q = sig->rawsig_no_b_val = store_get(Ustrlen(raw_hdr)+1); - -for (p = raw_hdr; ; p++) - { - char c = *p; - - /* Ignore FWS */ - if (c == '\r' || c == '\n') - goto NEXT_CHAR; - - /* Fast-forward through header name */ - if (!past_hname) - { - if (c == ':') past_hname = TRUE; - goto NEXT_CHAR; - } - - if (where == PDKIM_HDR_LIMBO) - { - /* In limbo, just wait for a tag-char to appear */ - if (!(c >= 'a' && c <= 'z')) - goto NEXT_CHAR; - - where = PDKIM_HDR_TAG; - } - - if (where == PDKIM_HDR_TAG) - { - if (c >= 'a' && c <= 'z') - cur_tag = string_catn(cur_tag, &ts, &tl, p, 1); - - if (c == '=') - { - cur_tag[tl] = '\0'; - if (Ustrcmp(cur_tag, "b") == 0) - { - *q++ = '='; - in_b_val = TRUE; - } - where = PDKIM_HDR_VALUE; - goto NEXT_CHAR; - } - } - - if (where == PDKIM_HDR_VALUE) - { - if (c == '\r' || c == '\n' || c == ' ' || c == '\t') - goto NEXT_CHAR; - - if (c == ';' || c == '\0') - { - if (tl && vl) - { - cur_val[vl] = '\0'; - pdkim_strtrim(cur_val); - - DEBUG(D_acl) debug_printf(" %s=%s\n", cur_tag, cur_val); - - switch (*cur_tag) - { - case 'b': - if (cur_tag[1] == 'h') - pdkim_decode_base64(cur_val, &sig->bodyhash); - else - pdkim_decode_base64(cur_val, &sig->sigdata); - break; - case 'v': - /* We only support version 1, and that is currently the - only version there is. */ - sig->version = - Ustrcmp(cur_val, PDKIM_SIGNATURE_VERSION) == 0 ? 1 : -1; - break; - case 'a': - for (i = 0; pdkim_algos[i]; i++) - if (Ustrcmp(cur_val, pdkim_algos[i]) == 0) - { - sig->algo = i; - break; - } - break; - case 'c': - for (i = 0; pdkim_combined_canons[i].str; i++) - if (Ustrcmp(cur_val, pdkim_combined_canons[i].str) == 0) - { - sig->canon_headers = pdkim_combined_canons[i].canon_headers; - sig->canon_body = pdkim_combined_canons[i].canon_body; - break; - } - break; - case 'q': - for (i = 0; pdkim_querymethods[i]; i++) - if (Ustrcmp(cur_val, pdkim_querymethods[i]) == 0) - { - sig->querymethod = i; - break; - } - break; - case 's': - sig->selector = string_copy(cur_val); break; - case 'd': - sig->domain = string_copy(cur_val); break; - case 'i': - sig->identity = pdkim_decode_qp(cur_val); break; - case 't': - sig->created = strtoul(CS cur_val, NULL, 10); break; - case 'x': - sig->expires = strtoul(CS cur_val, NULL, 10); break; - case 'l': - sig->bodylength = strtol(CS cur_val, NULL, 10); break; - case 'h': - sig->headernames = string_copy(cur_val); break; - case 'z': - sig->copiedheaders = pdkim_decode_qp(cur_val); break; - default: - DEBUG(D_acl) debug_printf(" Unknown tag encountered\n"); - break; - } - } - tl = 0; - vl = 0; - in_b_val = FALSE; - where = PDKIM_HDR_LIMBO; - } - else - cur_val = string_catn(cur_val, &vs, &vl, p, 1); - } - -NEXT_CHAR: - if (c == '\0') - break; - - if (!in_b_val) - *q++ = c; - } - -*q = '\0'; -/* Chomp raw header. The final newline must not be added to the signature. */ -while (--q > sig->rawsig_no_b_val && (*q == '\r' || *q == '\n')) - *q = '\0'; - -DEBUG(D_acl) - { - debug_printf( - "PDKIM >> Raw signature w/o b= tag value >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n"); - pdkim_quoteprint(US sig->rawsig_no_b_val, Ustrlen(sig->rawsig_no_b_val)); - debug_printf( - "PDKIM >> Sig size: %4u bits\n", (unsigned) sig->sigdata.len*8); - debug_printf( - "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n"); - } - -exim_sha_init(&sig->body_hash, sig->algo == PDKIM_ALGO_RSA_SHA1 ? HASH_SHA1 : HASH_SHA256); -return sig; -} - - -/* -------------------------------------------------------------------------- */ - -static pdkim_pubkey * -pdkim_parse_pubkey_record(pdkim_ctx *ctx, const uschar *raw_record) -{ -pdkim_pubkey *pub; -const uschar *p; -uschar * cur_tag = NULL; int ts = 0, tl = 0; -uschar * cur_val = NULL; int vs = 0, vl = 0; -int where = PDKIM_HDR_LIMBO; - -pub = store_get(sizeof(pdkim_pubkey)); -memset(pub, 0, sizeof(pdkim_pubkey)); - -for (p = raw_record; ; p++) - { - char c = *p; - - /* Ignore FWS */ - if (c == '\r' || c == '\n') - goto NEXT_CHAR; - - if (where == PDKIM_HDR_LIMBO) - { - /* In limbo, just wait for a tag-char to appear */ - if (!(c >= 'a' && c <= 'z')) - goto NEXT_CHAR; - - where = PDKIM_HDR_TAG; - } - - if (where == PDKIM_HDR_TAG) - { - if (c >= 'a' && c <= 'z') - cur_tag = string_catn(cur_tag, &ts, &tl, p, 1); - - if (c == '=') - { - cur_tag[tl] = '\0'; - where = PDKIM_HDR_VALUE; - goto NEXT_CHAR; - } - } - - if (where == PDKIM_HDR_VALUE) - { - if (c == ';' || c == '\0') - { - if (tl && vl) - { - cur_val[vl] = '\0'; - pdkim_strtrim(cur_val); - DEBUG(D_acl) debug_printf(" %s=%s\n", cur_tag, cur_val); - - switch (cur_tag[0]) - { - case 'v': - /* This tag isn't evaluated because: - - We only support version DKIM1. - - Which is the default for this value (set below) - - Other versions are currently not specified. */ - break; - case 'h': - case 'k': - pub->hashes = string_copy(cur_val); break; - case 'g': - pub->granularity = string_copy(cur_val); break; - case 'n': - pub->notes = pdkim_decode_qp(cur_val); break; - case 'p': - pdkim_decode_base64(US cur_val, &pub->key); - break; - case 's': - pub->srvtype = string_copy(cur_val); break; - case 't': - if (Ustrchr(cur_val, 'y') != NULL) pub->testing = 1; - if (Ustrchr(cur_val, 's') != NULL) pub->no_subdomaining = 1; - break; - default: - DEBUG(D_acl) debug_printf(" Unknown tag encountered\n"); - break; - } - } - tl = 0; - vl = 0; - where = PDKIM_HDR_LIMBO; - } - else - cur_val = string_catn(cur_val, &vs, &vl, p, 1); - } - -NEXT_CHAR: - if (c == '\0') break; - } - -/* Set fallback defaults */ -if (!pub->version ) pub->version = string_copy(PDKIM_PUB_RECORD_VERSION); -if (!pub->granularity) pub->granularity = string_copy(US"*"); -if (!pub->keytype ) pub->keytype = string_copy(US"rsa"); -if (!pub->srvtype ) pub->srvtype = string_copy(US"*"); - -/* p= is required */ -if (pub->key.data) - return pub; - -return NULL; -} - - -/* -------------------------------------------------------------------------- */ - -static int -pdkim_update_bodyhash(pdkim_ctx *ctx, const char *data, int len) -{ -pdkim_signature *sig = ctx->sig; -/* Cache relaxed version of data */ -uschar *relaxed_data = NULL; -int relaxed_len = 0; - -/* Traverse all signatures, updating their hashes. */ -while (sig) - { - /* Defaults to simple canon (no further treatment necessary) */ - const uschar *canon_data = CUS data; - int canon_len = len; - - if (sig->canon_body == PDKIM_CANON_RELAXED) - { - /* Relax the line if not done already */ - if (!relaxed_data) - { - BOOL seen_wsp = FALSE; - const char *p; - int q = 0; - - /* We want to be able to free this else we allocate - for the entire message which could be many MB. Since - we don't know what allocations the SHA routines might - do, not safe to use store_get()/store_reset(). */ - - relaxed_data = store_malloc(len+1); - - for (p = data; *p; p++) - { - char c = *p; - if (c == '\r') - { - if (q > 0 && relaxed_data[q-1] == ' ') - q--; - } - else if (c == '\t' || c == ' ') - { - c = ' '; /* Turns WSP into SP */ - if (seen_wsp) - continue; - seen_wsp = TRUE; - } - else - seen_wsp = FALSE; - relaxed_data[q++] = c; - } - relaxed_data[q] = '\0'; - relaxed_len = q; - } - canon_data = relaxed_data; - canon_len = relaxed_len; - } - - /* Make sure we don't exceed the to-be-signed body length */ - if ( sig->bodylength >= 0 - && sig->signed_body_bytes + (unsigned long)canon_len > sig->bodylength - ) - canon_len = sig->bodylength - sig->signed_body_bytes; - - if (canon_len > 0) - { - exim_sha_update(&sig->body_hash, CUS canon_data, canon_len); - sig->signed_body_bytes += canon_len; - DEBUG(D_acl) pdkim_quoteprint(canon_data, canon_len); - } - - sig = sig->next; - } - -if (relaxed_data) store_free(relaxed_data); -return PDKIM_OK; -} - - -/* -------------------------------------------------------------------------- */ - -static void -pdkim_finish_bodyhash(pdkim_ctx *ctx) -{ -pdkim_signature *sig; - -/* Traverse all signatures */ -for (sig = ctx->sig; sig; sig = sig->next) - { /* Finish hashes */ - blob bh; - - exim_sha_finish(&sig->body_hash, &bh); - - DEBUG(D_acl) - { - debug_printf("PDKIM [%s] Body bytes hashed: %lu\n" - "PDKIM [%s] bh computed: ", - sig->domain, sig->signed_body_bytes, sig->domain); - pdkim_hexprint(CUS bh.data, bh.len); - } - - /* SIGNING -------------------------------------------------------------- */ - if (ctx->flags & PDKIM_MODE_SIGN) - { - sig->bodyhash = bh; - - /* If bodylength limit is set, and we have received less bytes - than the requested amount, effectively remove the limit tag. */ - if (sig->signed_body_bytes < sig->bodylength) - sig->bodylength = -1; - } - - /* VERIFICATION --------------------------------------------------------- */ - else - { - /* Compare bodyhash */ - if (memcmp(bh.data, sig->bodyhash.data, bh.len) == 0) - { - DEBUG(D_acl) debug_printf("PDKIM [%s] Body hash verified OK\n", sig->domain); - } - else - { - DEBUG(D_acl) - { - debug_printf("PDKIM [%s] bh signature: ", sig->domain); - pdkim_hexprint(sig->bodyhash.data, - exim_sha_hashlen(&sig->body_hash)); - debug_printf("PDKIM [%s] Body hash did NOT verify\n", sig->domain); - } - sig->verify_status = PDKIM_VERIFY_FAIL; - sig->verify_ext_status = PDKIM_VERIFY_FAIL_BODY; - } - } - } -} - - - -static int -pdkim_body_complete(pdkim_ctx * ctx) -{ -pdkim_signature * sig = ctx->sig; /*XXX assumes only one sig */ - -/* In simple body mode, if any empty lines were buffered, -replace with one. rfc 4871 3.4.3 */ -/*XXX checking the signed-body-bytes is a gross hack; I think -it indicates that all linebreaks should be buffered, including -the one terminating a text line */ - -if ( sig && sig->canon_body == PDKIM_CANON_SIMPLE - && sig->signed_body_bytes == 0 - && ctx->num_buffered_crlf > 0 - ) - pdkim_update_bodyhash(ctx, "\r\n", 2); - -ctx->flags |= PDKIM_SEEN_EOD; -ctx->linebuf_offset = 0; -return PDKIM_OK; -} - - - -/* -------------------------------------------------------------------------- */ -/* Call from pdkim_feed below for processing complete body lines */ - -static int -pdkim_bodyline_complete(pdkim_ctx *ctx) -{ -char *p = ctx->linebuf; -int n = ctx->linebuf_offset; -pdkim_signature *sig = ctx->sig; /*XXX assumes only one sig */ - -/* Ignore extra data if we've seen the end-of-data marker */ -if (ctx->flags & PDKIM_SEEN_EOD) goto BAIL; - -/* We've always got one extra byte to stuff a zero ... */ -ctx->linebuf[ctx->linebuf_offset] = '\0'; - -/* Terminate on EOD marker */ -if (ctx->flags & PDKIM_DOT_TERM) - { - if ( memcmp(p, ".\r\n", 3) == 0) - return pdkim_body_complete(ctx); - - /* Unstuff dots */ - if (memcmp(p, "..", 2) == 0) - { - p++; - n--; - } - } - -/* Empty lines need to be buffered until we find a non-empty line */ -if (memcmp(p, "\r\n", 2) == 0) - { - ctx->num_buffered_crlf++; - goto BAIL; - } - -if (sig && sig->canon_body == PDKIM_CANON_RELAXED) - { - /* Lines with just spaces need to be buffered too */ - char *check = p; - while (memcmp(check, "\r\n", 2) != 0) - { - char c = *check; - - if (c != '\t' && c != ' ') - goto PROCESS; - check++; - } - - ctx->num_buffered_crlf++; - goto BAIL; -} - -PROCESS: -/* At this point, we have a non-empty line, so release the buffered ones. */ -while (ctx->num_buffered_crlf) - { - pdkim_update_bodyhash(ctx, "\r\n", 2); - ctx->num_buffered_crlf--; - } - -pdkim_update_bodyhash(ctx, p, n); - -BAIL: -ctx->linebuf_offset = 0; -return PDKIM_OK; -} - - -/* -------------------------------------------------------------------------- */ -/* Callback from pdkim_feed below for processing complete headers */ -#define DKIM_SIGNATURE_HEADERNAME "DKIM-Signature:" - -static int -pdkim_header_complete(pdkim_ctx *ctx) -{ -/* Special case: The last header can have an extra \r appended */ -if ( (ctx->cur_header_len > 1) && - (ctx->cur_header[(ctx->cur_header_len)-1] == '\r') ) - --ctx->cur_header_len; -ctx->cur_header[ctx->cur_header_len] = '\0'; - -ctx->num_headers++; -if (ctx->num_headers > PDKIM_MAX_HEADERS) goto BAIL; - -/* SIGNING -------------------------------------------------------------- */ -if (ctx->flags & PDKIM_MODE_SIGN) - { - pdkim_signature *sig; - - for (sig = ctx->sig; sig; sig = sig->next) /* Traverse all signatures */ - - /* Add header to the signed headers list (in reverse order) */ - sig->headers = pdkim_prepend_stringlist(sig->headers, - ctx->cur_header); - } - -/* VERIFICATION ----------------------------------------------------------- */ -/* DKIM-Signature: headers are added to the verification list */ -else - { - if (strncasecmp(CCS ctx->cur_header, - DKIM_SIGNATURE_HEADERNAME, - Ustrlen(DKIM_SIGNATURE_HEADERNAME)) == 0) - { - pdkim_signature *new_sig; - - /* Create and chain new signature block */ - DEBUG(D_acl) debug_printf( - "PDKIM >> Found sig, trying to parse >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n"); - - if ((new_sig = pdkim_parse_sig_header(ctx, ctx->cur_header))) - { - pdkim_signature *last_sig = ctx->sig; - if (!last_sig) - ctx->sig = new_sig; - else - { - while (last_sig->next) last_sig = last_sig->next; - last_sig->next = new_sig; - } - } - else - DEBUG(D_acl) debug_printf( - "Error while parsing signature header\n" - "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n"); - } - - /* every other header is stored for signature verification */ - else - ctx->headers = pdkim_prepend_stringlist(ctx->headers, ctx->cur_header); - } - -BAIL: -*ctx->cur_header = '\0'; -ctx->cur_header_len = 0; /* leave buffer for reuse */ -return PDKIM_OK; -} - - - -/* -------------------------------------------------------------------------- */ -#define HEADER_BUFFER_FRAG_SIZE 256 - -DLLEXPORT int -pdkim_feed(pdkim_ctx *ctx, char *data, int len) -{ -int p; - -/* Alternate EOD signal, used in non-dotstuffing mode */ -if (!data) - pdkim_body_complete(ctx); - -else for (p = 0; pflags & PDKIM_PAST_HDRS) - { - /* Processing body byte */ - ctx->linebuf[ctx->linebuf_offset++] = c; - if (c == '\n') - { - int rc = pdkim_bodyline_complete(ctx); /* End of line */ - if (rc != PDKIM_OK) return rc; - } - if (ctx->linebuf_offset == (PDKIM_MAX_BODY_LINE_LEN-1)) - return PDKIM_ERR_LONG_LINE; - } - else - { - /* Processing header byte */ - if (c != '\r') - { - if (c == '\n') - { - if (ctx->flags & PDKIM_SEEN_LF) - { - int rc = pdkim_header_complete(ctx); /* Seen last header line */ - if (rc != PDKIM_OK) return rc; - - ctx->flags = ctx->flags & ~PDKIM_SEEN_LF | PDKIM_PAST_HDRS; - DEBUG(D_acl) debug_printf( - "PDKIM >> Body data for hash, canonicalized >>>>>>>>>>>>>>>>>>>>>>\n"); - continue; - } - else - ctx->flags |= PDKIM_SEEN_LF; - } - else if (ctx->flags & PDKIM_SEEN_LF) - { - if (!(c == '\t' || c == ' ')) - { - int rc = pdkim_header_complete(ctx); /* End of header */ - if (rc != PDKIM_OK) return rc; - } - ctx->flags &= ~PDKIM_SEEN_LF; - } - } - - if (ctx->cur_header_len < PDKIM_MAX_HEADER_LEN) - ctx->cur_header = string_catn(ctx->cur_header, &ctx->cur_header_size, - &ctx->cur_header_len, CUS &data[p], 1); - } - } -return PDKIM_OK; -} - - - -/* Extend a grwong header with a continuation-linebreak */ -static uschar * -pdkim_hdr_cont(uschar * str, int * size, int * ptr, int * col) -{ -*col = 1; -return string_catn(str, size, ptr, US"\r\n\t", 3); -} - - - -/* - * RFC 5322 specifies that header line length SHOULD be no more than 78 - * lets make it so! - * pdkim_headcat - * - * returns uschar * (not nul-terminated) - * - * col: this int holds and receives column number (octets since last '\n') - * str: partial string to append to - * size: current buffer size for str - * ptr: current tail-pointer for str - * pad: padding, split line or space after before or after eg: ";" - * intro: - must join to payload eg "h=", usually the tag name - * payload: eg base64 data - long data can be split arbitrarily. - * - * this code doesn't fold the header in some of the places that RFC4871 - * allows: As per RFC5322(2.2.3) it only folds before or after tag-value - * pairs and inside long values. it also always spaces or breaks after the - * "pad" - * - * no guarantees are made for output given out-of range input. like tag - * names longer than 78, or bogus col. Input is assumed to be free of line breaks. - */ - -static uschar * -pdkim_headcat(int * col, uschar * str, int * size, int * ptr, - const uschar * pad, const uschar * intro, const uschar * payload) -{ -size_t l; - -if (pad) - { - l = Ustrlen(pad); - if (*col + l > 78) - str = pdkim_hdr_cont(str, size, ptr, col); - str = string_catn(str, size, ptr, pad, l); - *col += l; - } - -l = (pad?1:0) + (intro?Ustrlen(intro):0); - -if (*col + l > 78) - { /*can't fit intro - start a new line to make room.*/ - str = pdkim_hdr_cont(str, size, ptr, col); - l = intro?Ustrlen(intro):0; - } - -l += payload ? Ustrlen(payload):0 ; - -while (l>77) - { /* this fragment will not fit on a single line */ - if (pad) - { - str = string_catn(str, size, ptr, US" ", 1); - *col += 1; - pad = NULL; /* only want this once */ - l--; - } - - if (intro) - { - size_t sl = Ustrlen(intro); - - str = string_catn(str, size, ptr, intro, sl); - *col += sl; - l -= sl; - intro = NULL; /* only want this once */ - } - - if (payload) - { - size_t sl = Ustrlen(payload); - size_t chomp = *col+sl < 77 ? sl : 78-*col; - - str = string_catn(str, size, ptr, payload, chomp); - *col += chomp; - payload += chomp; - l -= chomp-1; - } - - /* the while precondition tells us it didn't fit. */ - str = pdkim_hdr_cont(str, size, ptr, col); - } - -if (*col + l > 78) - { - str = pdkim_hdr_cont(str, size, ptr, col); - pad = NULL; - } - -if (pad) - { - str = string_catn(str, size, ptr, US" ", 1); - *col += 1; - pad = NULL; - } - -if (intro) - { - size_t sl = Ustrlen(intro); - - str = string_catn(str, size, ptr, intro, sl); - *col += sl; - l -= sl; - intro = NULL; - } - -if (payload) - { - size_t sl = Ustrlen(payload); - - str = string_catn(str, size, ptr, payload, sl); - *col += sl; - } - -return str; -} - - -/* -------------------------------------------------------------------------- */ - -static uschar * -pdkim_create_header(pdkim_signature *sig, BOOL final) -{ -uschar * base64_bh; -uschar * base64_b; -int col = 0; -uschar * hdr; int hdr_size = 0, hdr_len = 0; -uschar * canon_all; int can_size = 0, can_len = 0; - -canon_all = string_cat (NULL, &can_size, &can_len, - pdkim_canons[sig->canon_headers]); -canon_all = string_catn(canon_all, &can_size, &can_len, US"/", 1); -canon_all = string_cat (canon_all, &can_size, &can_len, - pdkim_canons[sig->canon_body]); -canon_all[can_len] = '\0'; - -hdr = string_cat(NULL, &hdr_size, &hdr_len, - US"DKIM-Signature: v="PDKIM_SIGNATURE_VERSION); -col = hdr_len; - -/* Required and static bits */ -hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"a=", - pdkim_algos[sig->algo]); -hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"q=", - pdkim_querymethods[sig->querymethod]); -hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"c=", - canon_all); -hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"d=", - sig->domain); -hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"s=", - sig->selector); - -/* list of header names can be split between items. */ - { - uschar * n = string_copy(sig->headernames); - uschar * i = US"h="; - uschar * s = US";"; - - while (*n) - { - uschar * c = Ustrchr(n, ':'); - - if (c) *c ='\0'; - - if (!i) - hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, NULL, NULL, US":"); - - hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, s, i, n); - - if (!c) - break; - - n = c+1; - s = NULL; - i = NULL; - } - } - -base64_bh = pdkim_encode_base64(&sig->bodyhash); -hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"bh=", base64_bh); - -/* Optional bits */ -if (sig->identity) - hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"i=", sig->identity); - -if (sig->created > 0) - { - uschar minibuf[20]; - - snprintf(CS minibuf, sizeof(minibuf), "%lu", sig->created); - hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"t=", minibuf); -} - -if (sig->expires > 0) - { - uschar minibuf[20]; - - snprintf(CS minibuf, sizeof(minibuf), "%lu", sig->expires); - hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"x=", minibuf); - } - -if (sig->bodylength >= 0) - { - uschar minibuf[20]; - - snprintf(CS minibuf, sizeof(minibuf), "%lu", sig->bodylength); - hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"l=", minibuf); - } - -/* Preliminary or final version? */ -base64_b = final ? pdkim_encode_base64(&sig->sigdata) : US""; -hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"b=", base64_b); - -/* add trailing semicolon: I'm not sure if this is actually needed */ -hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, NULL, US";", US""); - -hdr[hdr_len] = '\0'; -return hdr; -} - - -/* -------------------------------------------------------------------------- */ - -DLLEXPORT int -pdkim_feed_finish(pdkim_ctx *ctx, pdkim_signature **return_signatures) -{ -pdkim_signature *sig = ctx->sig; - -/* Check if we must still flush a (partial) header. If that is the - case, the message has no body, and we must compute a body hash - out of '' */ -if (ctx->cur_header && ctx->cur_header_len) - { - int rc = pdkim_header_complete(ctx); - if (rc != PDKIM_OK) return rc; - pdkim_update_bodyhash(ctx, "\r\n", 2); - } -else - DEBUG(D_acl) debug_printf( - "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n"); - -/* Build (and/or evaluate) body hash */ -pdkim_finish_bodyhash(ctx); - -while (sig) - { - BOOL is_sha1 = sig->algo == PDKIM_ALGO_RSA_SHA1; - hctx hhash_ctx; - uschar * sig_hdr = US""; - blob hhash; - blob hdata; - int hdata_alloc = 0; - - hdata.data = NULL; - hdata.len = 0; - - exim_sha_init(&hhash_ctx, is_sha1 ? HASH_SHA1 : HASH_SHA256); - - DEBUG(D_acl) debug_printf( - "PDKIM >> Hashed header data, canonicalized, in sequence >>>>>>>>>>>>>>\n"); - - /* SIGNING ---------------------------------------------------------------- */ - /* When signing, walk through our header list and add them to the hash. As we - go, construct a list of the header's names to use for the h= parameter. - Then append to that list any remaining header names for which there was no - header to sign. */ - - if (ctx->flags & PDKIM_MODE_SIGN) - { - uschar * headernames = NULL; /* Collected signed header names */ - int hs = 0, hl = 0; - pdkim_stringlist *p; - const uschar * l; - uschar * s; - int sep = 0; - - for (p = sig->headers; p; p = p->next) - if (header_name_match(p->value, sig->sign_headers) == PDKIM_OK) - { - uschar * rh; - /* Collect header names (Note: colon presence is guaranteed here) */ - uschar * q = Ustrchr(p->value, ':'); - - headernames = string_catn(headernames, &hs, &hl, - p->value, (q - US p->value) + (p->next ? 1 : 0)); - - rh = sig->canon_headers == PDKIM_CANON_RELAXED - ? pdkim_relax_header(p->value, 1) /* cook header for relaxed canon */ - : string_copy(CUS p->value); /* just copy it for simple canon */ - - /* Feed header to the hash algorithm */ - exim_sha_update(&hhash_ctx, CUS rh, Ustrlen(rh)); - - /* Remember headers block for signing (when the library cannot do incremental) */ - (void) exim_rsa_data_append(&hdata, &hdata_alloc, rh); - - DEBUG(D_acl) pdkim_quoteprint(rh, Ustrlen(rh)); - } - - l = sig->sign_headers; - while((s = string_nextinlist(&l, &sep, NULL, 0))) - if (*s != '_') - { /*SSS string_append_listele() */ - if (hl > 0 && headernames[hl-1] != ':') - headernames = string_catn(headernames, &hs, &hl, US":", 1); - - headernames = string_cat(headernames, &hs, &hl, s); - } - headernames[hl] = '\0'; - - /* Copy headernames to signature struct */ - sig->headernames = headernames; - - /* Create signature header with b= omitted */ - sig_hdr = pdkim_create_header(sig, FALSE); - } - - /* VERIFICATION ----------------------------------------------------------- */ - /* When verifying, walk through the header name list in the h= parameter and - add the headers to the hash in that order. */ - else - { - uschar * p = sig->headernames; - uschar * q; - pdkim_stringlist * hdrs; - - if (p) - { - /* clear tags */ - for (hdrs = ctx->headers; hdrs; hdrs = hdrs->next) - hdrs->tag = 0; - - p = string_copy(p); - while(1) - { - if ((q = Ustrchr(p, ':'))) - *q = '\0'; - - /*XXX walk the list of headers in same order as received. */ - for (hdrs = ctx->headers; hdrs; hdrs = hdrs->next) - if ( hdrs->tag == 0 - && strncasecmp(CCS hdrs->value, CCS p, Ustrlen(p)) == 0 - && (hdrs->value)[Ustrlen(p)] == ':' - ) - { - /* cook header for relaxed canon, or just copy it for simple */ - - uschar * rh = sig->canon_headers == PDKIM_CANON_RELAXED - ? pdkim_relax_header(hdrs->value, 1) - : string_copy(CUS hdrs->value); - - /* Feed header to the hash algorithm */ - exim_sha_update(&hhash_ctx, CUS rh, Ustrlen(rh)); - - DEBUG(D_acl) pdkim_quoteprint(rh, Ustrlen(rh)); - hdrs->tag = 1; - break; - } - - if (!q) break; - p = q+1; - } - - sig_hdr = string_copy(sig->rawsig_no_b_val); - } - } - - DEBUG(D_acl) debug_printf( - "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n"); - - /* Relax header if necessary */ - if (sig->canon_headers == PDKIM_CANON_RELAXED) - sig_hdr = pdkim_relax_header(sig_hdr, 0); - - DEBUG(D_acl) - { - debug_printf( - "PDKIM >> Signed DKIM-Signature header, canonicalized >>>>>>>>>>>>>>>>>\n"); - pdkim_quoteprint(CUS sig_hdr, Ustrlen(sig_hdr)); - debug_printf( - "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n"); - } - - /* Finalize header hash */ - exim_sha_update(&hhash_ctx, CUS sig_hdr, Ustrlen(sig_hdr)); - exim_sha_finish(&hhash_ctx, &hhash); - - DEBUG(D_acl) - { - debug_printf("PDKIM [%s] hh computed: ", sig->domain); - pdkim_hexprint(hhash.data, hhash.len); - } - - /* Remember headers block for signing (when the library cannot do incremental) */ - if (ctx->flags & PDKIM_MODE_SIGN) - (void) exim_rsa_data_append(&hdata, &hdata_alloc, US sig_hdr); - - /* SIGNING ---------------------------------------------------------------- */ - if (ctx->flags & PDKIM_MODE_SIGN) - { - es_ctx sctx; - const uschar * errstr; - - /* Import private key */ - if ((errstr = exim_rsa_signing_init(US sig->rsa_privkey, &sctx))) - { - DEBUG(D_acl) debug_printf("signing_init: %s\n", errstr); - return PDKIM_ERR_RSA_PRIVKEY; - } - - /* Do signing. With OpenSSL we are signing the hash of headers just - calculated, with GnuTLS we have to sign an entire block of headers - (due to available interfaces) and it recalculates the hash internally. */ - -#if defined(RSA_OPENSSL) || defined(RSA_GCRYPT) - hdata = hhash; -#endif - - if ((errstr = exim_rsa_sign(&sctx, is_sha1, &hdata, &sig->sigdata))) - { - DEBUG(D_acl) debug_printf("signing: %s\n", errstr); - return PDKIM_ERR_RSA_SIGNING; - } - - DEBUG(D_acl) - { - debug_printf( "PDKIM [%s] b computed: ", sig->domain); - pdkim_hexprint(sig->sigdata.data, sig->sigdata.len); - } - - sig->signature_header = pdkim_create_header(sig, TRUE); - } - - /* VERIFICATION ----------------------------------------------------------- */ - else - { - ev_ctx vctx; - const uschar * errstr; - - uschar *dns_txt_name, *dns_txt_reply; - - /* Make sure we have all required signature tags */ - if (!( sig->domain && *sig->domain - && sig->selector && *sig->selector - && sig->headernames && *sig->headernames - && sig->bodyhash.data - && sig->sigdata.data - && sig->algo > -1 - && sig->version - ) ) - { - sig->verify_status = PDKIM_VERIFY_INVALID; - sig->verify_ext_status = PDKIM_VERIFY_INVALID_SIGNATURE_ERROR; - - DEBUG(D_acl) debug_printf( - " Error in DKIM-Signature header: tags missing or invalid\n" - "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n"); - goto NEXT_VERIFY; - } - - /* Make sure sig uses supported DKIM version (only v1) */ - if (sig->version != 1) - { - sig->verify_status = PDKIM_VERIFY_INVALID; - sig->verify_ext_status = PDKIM_VERIFY_INVALID_DKIM_VERSION; - - DEBUG(D_acl) debug_printf( - " Error in DKIM-Signature header: unsupported DKIM version\n" - "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n"); - goto NEXT_VERIFY; - } - - /* Fetch public key for signing domain, from DNS */ - - dns_txt_name = string_sprintf("%s._domainkey.%s.", - sig->selector, sig->domain); - - dns_txt_reply = store_get(PDKIM_DNS_TXT_MAX_RECLEN); - memset(dns_txt_reply, 0, PDKIM_DNS_TXT_MAX_RECLEN); - - if ( ctx->dns_txt_callback(CS dns_txt_name, CS dns_txt_reply) != PDKIM_OK - || dns_txt_reply[0] == '\0') - { - sig->verify_status = PDKIM_VERIFY_INVALID; - sig->verify_ext_status = PDKIM_VERIFY_INVALID_PUBKEY_UNAVAILABLE; - goto NEXT_VERIFY; - } - - DEBUG(D_acl) - { - debug_printf( - "PDKIM >> Parsing public key record >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n" - " Raw record: "); - pdkim_quoteprint(CUS dns_txt_reply, Ustrlen(dns_txt_reply)); - } - - if (!(sig->pubkey = pdkim_parse_pubkey_record(ctx, CUS dns_txt_reply))) - { - sig->verify_status = PDKIM_VERIFY_INVALID; - sig->verify_ext_status = PDKIM_VERIFY_INVALID_PUBKEY_DNSRECORD; - - DEBUG(D_acl) debug_printf( - " Error while parsing public key record\n" - "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n"); - goto NEXT_VERIFY; - } - - DEBUG(D_acl) debug_printf( - "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n"); - - /* Import public key */ - if ((errstr = exim_rsa_verify_init(&sig->pubkey->key, &vctx))) - { - DEBUG(D_acl) debug_printf("verify_init: %s\n", errstr); - sig->verify_status = PDKIM_VERIFY_INVALID; - sig->verify_ext_status = PDKIM_VERIFY_INVALID_PUBKEY_IMPORT; - goto NEXT_VERIFY; - } - - /* Check the signature */ - if ((errstr = exim_rsa_verify(&vctx, is_sha1, &hhash, &sig->sigdata))) - { - DEBUG(D_acl) debug_printf("headers verify: %s\n", errstr); - sig->verify_status = PDKIM_VERIFY_FAIL; - sig->verify_ext_status = PDKIM_VERIFY_FAIL_MESSAGE; - goto NEXT_VERIFY; - } - - - /* We have a winner! (if bodydhash was correct earlier) */ - if (sig->verify_status == PDKIM_VERIFY_NONE) - sig->verify_status = PDKIM_VERIFY_PASS; - -NEXT_VERIFY: - - DEBUG(D_acl) - { - debug_printf("PDKIM [%s] signature status: %s", - sig->domain, pdkim_verify_status_str(sig->verify_status)); - if (sig->verify_ext_status > 0) - debug_printf(" (%s)\n", - pdkim_verify_ext_status_str(sig->verify_ext_status)); - else - debug_printf("\n"); - } - } - - sig = sig->next; - } - -/* If requested, set return pointer to signature(s) */ -if (return_signatures) - *return_signatures = ctx->sig; - -return PDKIM_OK; -} - - -/* -------------------------------------------------------------------------- */ - -DLLEXPORT pdkim_ctx * -pdkim_init_verify(int(*dns_txt_callback)(char *, char *), BOOL dot_stuffing) -{ -pdkim_ctx * ctx; - -ctx = store_get(sizeof(pdkim_ctx)); -memset(ctx, 0, sizeof(pdkim_ctx)); - -if (dot_stuffing) ctx->flags = PDKIM_DOT_TERM; -ctx->linebuf = store_get(PDKIM_MAX_BODY_LINE_LEN); -ctx->dns_txt_callback = dns_txt_callback; - -return ctx; -} - - -/* -------------------------------------------------------------------------- */ - -DLLEXPORT pdkim_ctx * -pdkim_init_sign(char *domain, char *selector, char *rsa_privkey, int algo, - BOOL dot_stuffed) -{ -pdkim_ctx *ctx; -pdkim_signature *sig; - -if (!domain || !selector || !rsa_privkey) - return NULL; - -ctx = store_get(sizeof(pdkim_ctx)); -memset(ctx, 0, sizeof(pdkim_ctx)); - -ctx->flags = dot_stuffed ? PDKIM_MODE_SIGN | PDKIM_DOT_TERM : PDKIM_MODE_SIGN; -ctx->linebuf = store_get(PDKIM_MAX_BODY_LINE_LEN); - -sig = store_get(sizeof(pdkim_signature)); -memset(sig, 0, sizeof(pdkim_signature)); - -sig->bodylength = -1; -ctx->sig = sig; - -sig->domain = string_copy(US domain); -sig->selector = string_copy(US selector); -sig->rsa_privkey = string_copy(US rsa_privkey); -sig->algo = algo; - -exim_sha_init(&sig->body_hash, algo == PDKIM_ALGO_RSA_SHA1 ? HASH_SHA1 : HASH_SHA256); -return ctx; -} - - -/* -------------------------------------------------------------------------- */ - -DLLEXPORT int -pdkim_set_optional(pdkim_ctx *ctx, - char *sign_headers, - char *identity, - int canon_headers, - int canon_body, - long bodylength, - unsigned long created, - unsigned long expires) -{ -pdkim_signature * sig = ctx->sig; - -if (identity) - sig->identity = string_copy(US identity); - -sig->sign_headers = string_copy(sign_headers - ? US sign_headers : US PDKIM_DEFAULT_SIGN_HEADERS); - -sig->canon_headers = canon_headers; -sig->canon_body = canon_body; -sig->bodylength = bodylength; -sig->created = created; -sig->expires = expires; - -return PDKIM_OK; -} - - -void -pdkim_init(void) -{ -exim_rsa_init(); -} - - - -#endif /*DISABLE_DKIM*/