+++ /dev/null
-/*
- * PDKIM - a RFC4871 (DKIM) implementation
- *
- * Copyright (C) 2009 - 2016 Tom Kistner <tom@duncanthrax.net>
- * Copyright (C) 2016 Jeremy Harris <jgh@exim.org>
- *
- * 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 <openssl/rsa.h>
-# include <openssl/ssl.h>
-# include <openssl/err.h>
-#elif defined(RSA_GNUTLS)
-# include <gnutls/gnutls.h>
-# include <gnutls/x509.h>
-#endif
-
-#include "pdkim.h"
-#include "rsa.h"
-
-#define PDKIM_SIGNATURE_VERSION "1"
-#define PDKIM_PUB_RECORD_VERSION "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 {
- char *value;
- int tag;
- void *next;
-};
-
-#define PDKIM_STR_ALLOC_FRAG 256
-struct pdkim_str {
- char *str;
- unsigned int len;
- unsigned int allocated;
-};
-
-/* -------------------------------------------------------------------------- */
-/* A bunch of list constants */
-const char *pdkim_querymethods[] = {
- "dns/txt",
- NULL
-};
-const char *pdkim_algos[] = {
- "rsa-sha256",
- "rsa-sha1",
- NULL
-};
-const char *pdkim_canons[] = {
- "simple",
- "relaxed",
- NULL
-};
-const char *pdkim_hashes[] = {
- "sha256",
- "sha1",
- NULL
-};
-const char *pdkim_keytypes[] = {
- "rsa",
- NULL
-};
-
-typedef struct pdkim_combined_canon_entry {
- const char *str;
- int canon_headers;
- int canon_body;
-} pdkim_combined_canon_entry;
-
-pdkim_combined_canon_entry pdkim_combined_canons[] = {
- { "simple/simple", PDKIM_CANON_SIMPLE, PDKIM_CANON_SIMPLE },
- { "simple/relaxed", PDKIM_CANON_SIMPLE, PDKIM_CANON_RELAXED },
- { "relaxed/simple", PDKIM_CANON_RELAXED, PDKIM_CANON_SIMPLE },
- { "relaxed/relaxed", PDKIM_CANON_RELAXED, PDKIM_CANON_RELAXED },
- { "simple", PDKIM_CANON_SIMPLE, PDKIM_CANON_SIMPLE },
- { "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";
- default: return "PDKIM_VERIFY_UNKNOWN";
- }
-}
-
-
-/* -------------------------------------------------------------------------- */
-/* Print debugging functions */
-static void
-pdkim_quoteprint(const char *data, int len)
-{
-int i;
-const unsigned char *p = (const unsigned char *)data;
-
-for (i = 0; i < len; i++)
- {
- const int c = p[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 char *data, int len)
-{
-int i;
-const unsigned char *p = (const unsigned char *)data;
-
-for (i = 0 ; i < len; i++)
- debug_printf("%02x", p[i]);
-debug_printf("\n");
-}
-
-
-
-/* String package: should be replaced by Exim standard ones */
-
-static pdkim_stringlist *
-pdkim_prepend_stringlist(pdkim_stringlist *base, char *str)
-{
-pdkim_stringlist *new_entry = malloc(sizeof(pdkim_stringlist));
-
-if (!new_entry) return NULL;
-memset(new_entry, 0, sizeof(pdkim_stringlist));
-if (!(new_entry->value = strdup(str))) return NULL;
-if (base)
- {
- pdkim_stringlist *last = base;
- while (last->next != NULL) { last = last->next; }
- last->next = new_entry;
- return base;
- }
-else
- return new_entry;
-}
-
-
-/* -------------------------------------------------------------------------- */
-/* A small "growing string" implementation to escape malloc/realloc hell */
-
-static pdkim_str *
-pdkim_strnew (const char *cstr)
-{
-unsigned int len = cstr ? strlen(cstr) : 0;
-pdkim_str *p = malloc(sizeof(pdkim_str));
-
-if (!p) return NULL;
-memset(p, 0, sizeof(pdkim_str));
-if (!(p->str = malloc(len+1)))
- {
- free(p);
- return NULL;
- }
-p->allocated = len+1;
-p->len = len;
-if (cstr)
- strcpy(p->str, cstr);
-else
- p->str[p->len] = '\0';
-return p;
-}
-
-static char *
-pdkim_strncat(pdkim_str *str, const char *data, int len)
-{
-if ((str->allocated - str->len) < (len+1))
- {
- /* Extend the buffer */
- int num_frags = ((len+1)/PDKIM_STR_ALLOC_FRAG)+1;
- char *n = realloc(str->str,
- (str->allocated+(num_frags*PDKIM_STR_ALLOC_FRAG)));
- if (n == NULL) return NULL;
- str->str = n;
- str->allocated += (num_frags*PDKIM_STR_ALLOC_FRAG);
- }
-strncpy(&(str->str[str->len]), data, len);
-str->len += len;
-str->str[str->len] = '\0';
-return str->str;
-}
-
-static char *
-pdkim_strcat(pdkim_str *str, const char *cstr)
-{
-return pdkim_strncat(str, cstr, strlen(cstr));
-}
-
-static char *
-pdkim_strtrim(pdkim_str *str)
-{
-char *p = str->str;
-char *q = str->str;
-while ( (*p != '\0') && ((*p == '\t') || (*p == ' ')) ) p++;
-while (*p != '\0') {*q = *p; q++; p++;}
-*q = '\0';
-while ( (q != str->str) && ( (*q == '\0') || (*q == '\t') || (*q == ' ') ) )
- {
- *q = '\0';
- q--;
- }
-str->len = strlen(str->str);
-return str->str;
-}
-
-static char *
-pdkim_strclear(pdkim_str *str)
-{
-str->str[0] = '\0';
-str->len = 0;
-return str->str;
-}
-
-static void
-pdkim_strfree(pdkim_str *str)
-{
-if (!str) return;
-if (str->str) free(str->str);
-free(str);
-}
-
-
-
-/* -------------------------------------------------------------------------- */
-
-static void
-pdkim_free_pubkey(pdkim_pubkey *pub)
-{
-if (pub)
- {
- if (pub->version ) free(pub->version);
- if (pub->granularity) free(pub->granularity);
- if (pub->hashes ) free(pub->hashes);
- if (pub->keytype ) free(pub->keytype);
- if (pub->srvtype ) free(pub->srvtype);
- if (pub->notes ) free(pub->notes);
- free(pub);
- }
-}
-
-
-/* -------------------------------------------------------------------------- */
-
-static void
-pdkim_free_sig(pdkim_signature *sig)
-{
-if (sig)
- {
- pdkim_signature *next = (pdkim_signature *)sig->next;
-
- pdkim_stringlist *e = sig->headers;
- while(e)
- {
- pdkim_stringlist *c = e;
- if (e->value) free(e->value);
- e = e->next;
- free(c);
- }
-
- if (sig->selector ) free(sig->selector);
- if (sig->domain ) free(sig->domain);
- if (sig->identity ) free(sig->identity);
- if (sig->copiedheaders ) free(sig->copiedheaders);
- if (sig->rsa_privkey ) free(sig->rsa_privkey);
- if (sig->sign_headers ) free(sig->sign_headers);
- if (sig->signature_header) free(sig->signature_header);
-
- if (sig->pubkey) pdkim_free_pubkey(sig->pubkey);
-
- free(sig);
- if (next) pdkim_free_sig(next);
- }
-}
-
-
-/* -------------------------------------------------------------------------- */
-
-DLLEXPORT void
-pdkim_free_ctx(pdkim_ctx *ctx)
-{
-if (ctx)
- {
- pdkim_stringlist *e = ctx->headers;
- while(e)
- {
- pdkim_stringlist *c = e;
- if (e->value) free(e->value);
- e = e->next;
- free(c);
- }
- pdkim_free_sig(ctx->sig);
- pdkim_strfree(ctx->cur_header);
- free(ctx);
- }
-}
-
-
-/* -------------------------------------------------------------------------- */
-/* Matches the name of the passed raw "header" against
- the passed colon-separated "list", starting at entry
- "start". Returns the position of the header name in
- the list. */
-
-static int
-header_name_match(const char *header,
- char *tick,
- int do_tick)
-{
-char *hname;
-char *lcopy;
-char *p;
-char *q;
-int rc = PDKIM_FAIL;
-
-/* Get header name */
-char *hcolon = strchr(header, ':');
-
-if (!hcolon) return rc; /* This isn't a header */
-
-if (!(hname = malloc((hcolon-header)+1)))
- return PDKIM_ERR_OOM;
-memset(hname, 0, (hcolon-header)+1);
-strncpy(hname, header, (hcolon-header));
-
-/* Copy tick-off list locally, so we can punch zeroes into it */
-if (!(lcopy = strdup(tick)))
- {
- free(hname);
- return PDKIM_ERR_OOM;
- }
-p = lcopy;
-q = strchr(p, ':');
-while (q)
- {
- *q = '\0';
-
- if (strcasecmp(p, hname) == 0)
- {
- rc = PDKIM_OK;
- /* Invalidate header name instance in tick-off list */
- if (do_tick) tick[p-lcopy] = '_';
- goto BAIL;
- }
-
- p = q+1;
- q = strchr(p, ':');
- }
-
-if (strcasecmp(p, hname) == 0)
- {
- rc = PDKIM_OK;
- /* Invalidate header name instance in tick-off list */
- if (do_tick) tick[p-lcopy] = '_';
- }
-
-BAIL:
-free(hname);
-free(lcopy);
-return rc;
-}
-
-
-/* -------------------------------------------------------------------------- */
-/* Performs "relaxed" canonicalization of a header. The returned pointer needs
- to be free()d. */
-
-static char *
-pdkim_relax_header (char *header, int crlf)
-{
-BOOL past_field_name = FALSE;
-BOOL seen_wsp = FALSE;
-char *p;
-char *q;
-char *relaxed = malloc(strlen(header)+3);
-
-if (!relaxed) return NULL;
-
-q = relaxed;
-for (p = header; *p != '\0'; p++)
- {
- int 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 */
-*q = '\0';
-
-if (crlf) strcat(relaxed, "\r\n");
-return relaxed;
-}
-
-
-/* -------------------------------------------------------------------------- */
-#define PDKIM_QP_ERROR_DECODE -1
-
-static char *
-pdkim_decode_qp_char(char *qp_p, int *c)
-{
-char *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 char *
-pdkim_decode_qp(char *str)
-{
-int nchar = 0;
-char *q;
-char *p = str;
-char *n = malloc(strlen(p)+1);
-
-if (!n) return NULL;
-
-*n = '\0';
-q = n;
-while (*p != '\0')
- {
- 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;
-char *res;
-dlen = b64decode(str, &b->data);
-if (dlen < 0) b->data = NULL;
-b->len = dlen;
-}
-
-/* -------------------------------------------------------------------------- */
-
-static char *
-pdkim_encode_base64(blob * b)
-{
-char * ret;
-int old_pool = store_pool;
-
-store_pool = POOL_PERM;
-ret = CS b64encode(b->data, b->len);
-store_pool = old_pool;
-return ret;
-}
-
-
-/* -------------------------------------------------------------------------- */
-#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, char *raw_hdr)
-{
-pdkim_signature *sig ;
-char *p, *q;
-pdkim_str *cur_tag = NULL;
-pdkim_str *cur_val = NULL;
-BOOL past_hname = FALSE;
-BOOL in_b_val = FALSE;
-int where = PDKIM_HDR_LIMBO;
-int i;
-int old_pool = store_pool;
-
-/* There is a store-reset between header & body reception
-so cannot use the main pool. Any allocs done by Exim
-memory-handling must use the perm pool. */
-
-store_pool = POOL_PERM;
-
-if (!(sig = malloc(sizeof(pdkim_signature)))) return NULL;
-memset(sig, 0, sizeof(pdkim_signature));
-sig->bodylength = -1;
-
-if (!(sig->rawsig_no_b_val = malloc(strlen(raw_hdr)+1)))
- {
- free(sig);
- return NULL;
- }
-
-q = sig->rawsig_no_b_val;
-
-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 (!cur_tag)
- cur_tag = pdkim_strnew(NULL);
-
- if (c >= 'a' && c <= 'z')
- pdkim_strncat(cur_tag, p, 1);
-
- if (c == '=')
- {
- if (strcmp(cur_tag->str, "b") == 0)
- {
- *q = '='; q++;
- in_b_val = TRUE;
- }
- where = PDKIM_HDR_VALUE;
- goto NEXT_CHAR;
- }
- }
-
- if (where == PDKIM_HDR_VALUE)
- {
- if (!cur_val)
- cur_val = pdkim_strnew(NULL);
-
- if (c == '\r' || c == '\n' || c == ' ' || c == '\t')
- goto NEXT_CHAR;
-
- if (c == ';' || c == '\0')
- {
- if (cur_tag->len > 0)
- {
- pdkim_strtrim(cur_val);
-
- DEBUG(D_acl) debug_printf(" %s=%s\n", cur_tag->str, cur_val->str);
-
- switch (cur_tag->str[0])
- {
- case 'b':
- if (cur_tag->str[1] == 'h')
- pdkim_decode_base64(US cur_val->str, &sig->bodyhash);
- else
- pdkim_decode_base64(US cur_val->str, &sig->sigdata);
- break;
- case 'v':
- /* We only support version 1, and that is currently the
- only version there is. */
- if (strcmp(cur_val->str, PDKIM_SIGNATURE_VERSION) == 0)
- sig->version = 1;
- break;
- case 'a':
- for (i = 0; pdkim_algos[i]; i++)
- if (strcmp(cur_val->str, pdkim_algos[i]) == 0)
- {
- sig->algo = i;
- break;
- }
- break;
- case 'c':
- for (i = 0; pdkim_combined_canons[i].str; i++)
- if (strcmp(cur_val->str, 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 (strcmp(cur_val->str, pdkim_querymethods[i]) == 0)
- {
- sig->querymethod = i;
- break;
- }
- break;
- case 's':
- sig->selector = strdup(cur_val->str); break;
- case 'd':
- sig->domain = strdup(cur_val->str); break;
- case 'i':
- sig->identity = pdkim_decode_qp(cur_val->str); break;
- case 't':
- sig->created = strtoul(cur_val->str, NULL, 10); break;
- case 'x':
- sig->expires = strtoul(cur_val->str, NULL, 10); break;
- case 'l':
- sig->bodylength = strtol(cur_val->str, NULL, 10); break;
- case 'h':
- sig->headernames = string_copy(cur_val->str); break;
- case 'z':
- sig->copiedheaders = pdkim_decode_qp(cur_val->str); break;
- default:
- DEBUG(D_acl) debug_printf(" Unknown tag encountered\n");
- break;
- }
- }
- pdkim_strclear(cur_tag);
- pdkim_strclear(cur_val);
- in_b_val = FALSE;
- where = PDKIM_HDR_LIMBO;
- }
- else
- pdkim_strncat(cur_val, p, 1);
- }
-
-NEXT_CHAR:
- if (c == '\0')
- break;
-
- if (!in_b_val)
- *q++ = c;
- }
-
-store_pool = old_pool;
-
-/* Make sure the most important bits are there. */
-if (!(sig->domain && (*(sig->domain) != '\0') &&
- sig->selector && (*(sig->selector) != '\0') &&
- sig->headernames && (*(sig->headernames) != '\0') &&
- sig->version))
- {
- pdkim_free_sig(sig);
- return NULL;
- }
-
-*q = '\0';
-/* Chomp raw header. The final newline must not be added to the signature. */
-q--;
-while (q > sig->rawsig_no_b_val && (*q == '\r' || *q == '\n'))
- *q = '\0'; q--; /*XXX questionable code layout; possible bug */
-
-DEBUG(D_acl)
- {
- debug_printf(
- "PDKIM >> Raw signature w/o b= tag value >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
- pdkim_quoteprint(sig->rawsig_no_b_val, strlen(sig->rawsig_no_b_val));
- debug_printf(
- "PDKIM >> Sig size: %4d bits\n", sig->sigdata.len*8);
- debug_printf(
- "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
- }
-
-exim_sha_init(&sig->body_hash, sig->algo == PDKIM_ALGO_RSA_SHA1);
-return sig;
-}
-
-
-/* -------------------------------------------------------------------------- */
-
-static pdkim_pubkey *
-pdkim_parse_pubkey_record(pdkim_ctx *ctx, char *raw_record)
-{
-pdkim_pubkey *pub;
-char *p;
-pdkim_str *cur_tag = NULL;
-pdkim_str *cur_val = NULL;
-int where = PDKIM_HDR_LIMBO;
-
-if (!(pub = malloc(sizeof(pdkim_pubkey)))) return NULL;
-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 (!cur_tag)
- cur_tag = pdkim_strnew(NULL);
-
- if (c >= 'a' && c <= 'z')
- pdkim_strncat(cur_tag, p, 1);
-
- if (c == '=')
- {
- where = PDKIM_HDR_VALUE;
- goto NEXT_CHAR;
- }
- }
-
- if (where == PDKIM_HDR_VALUE)
- {
- if (!cur_val)
- cur_val = pdkim_strnew(NULL);
-
- if (c == '\r' || c == '\n')
- goto NEXT_CHAR;
-
- if (c == ';' || c == '\0')
- {
- if (cur_tag->len > 0)
- {
- pdkim_strtrim(cur_val);
- DEBUG(D_acl) debug_printf(" %s=%s\n", cur_tag->str, cur_val->str);
-
- switch (cur_tag->str[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':
- pub->hashes = strdup(cur_val->str); break;
- case 'g':
- pub->granularity = strdup(cur_val->str); break;
- case 'n':
- pub->notes = pdkim_decode_qp(cur_val->str); break;
- case 'p':
- pdkim_decode_base64(US cur_val->str, &pub->key);
- break;
- case 'k':
- pub->hashes = strdup(cur_val->str); break;
- case 's':
- pub->srvtype = strdup(cur_val->str); break;
- case 't':
- if (strchr(cur_val->str, 'y') != NULL) pub->testing = 1;
- if (strchr(cur_val->str, 's') != NULL) pub->no_subdomaining = 1;
- break;
- default:
- DEBUG(D_acl) debug_printf(" Unknown tag encountered\n");
- break;
- }
- }
- pdkim_strclear(cur_tag);
- pdkim_strclear(cur_val);
- where = PDKIM_HDR_LIMBO;
- }
- else
- pdkim_strncat(cur_val, p, 1);
- }
-
-NEXT_CHAR:
- if (c == '\0') break;
- }
-
-/* Set fallback defaults */
-if (!pub->version ) pub->version = strdup(PDKIM_PUB_RECORD_VERSION);
-if (!pub->granularity) pub->granularity = strdup("*");
-if (!pub->keytype ) pub->keytype = strdup("rsa");
-if (!pub->srvtype ) pub->srvtype = strdup("*");
-
-/* p= is required */
-if (pub->key.data)
- return pub;
-
-pdkim_free_pubkey(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 */
-char *relaxed_data = NULL;
-int relaxed_len = 0;
-
-/* Traverse all signatures, updating their hashes. */
-while (sig)
- {
- /* Defaults to simple canon (no further treatment necessary) */
- const char *canon_data = 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;
-
- if (!(relaxed_data = malloc(len+1)))
- return PDKIM_ERR_OOM;
-
- 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, 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) free(relaxed_data);
-return PDKIM_OK;
-}
-
-
-/* -------------------------------------------------------------------------- */
-
-static int
-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(CS bh.data, bh.len);
- }
-
- /* SIGNING -------------------------------------------------------------- */
- if (ctx->mode == 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;
- }
- }
- }
-
-return PDKIM_OK;
-}
-
-
-
-/* -------------------------------------------------------------------------- */
-/* Callback 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->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 (memcmp(p, ".\r\n", 3) == 0)
- {
- /* 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->seen_eod = TRUE;
- goto BAIL;
- }
-/* 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->str[(ctx->cur_header->len)-1] == '\r') )
- {
- ctx->cur_header->str[(ctx->cur_header->len)-1] = '\0';
- ctx->cur_header->len--;
- }
-
-ctx->num_headers++;
-if (ctx->num_headers > PDKIM_MAX_HEADERS) goto BAIL;
-
-/* SIGNING -------------------------------------------------------------- */
-if (ctx->mode == PDKIM_MODE_SIGN)
- {
- pdkim_signature *sig;
-
- for (sig = ctx->sig; sig; sig = sig->next) /* Traverse all signatures */
- if (header_name_match(ctx->cur_header->str,
- sig->sign_headers?
- sig->sign_headers:
- PDKIM_DEFAULT_SIGN_HEADERS, 0) == PDKIM_OK)
- {
- pdkim_stringlist *list;
-
- /* Add header to the signed headers list (in reverse order) */
- if (!(list = pdkim_prepend_stringlist(sig->headers,
- ctx->cur_header->str)))
- return PDKIM_ERR_OOM;
- sig->headers = list;
- }
- }
-
-/* VERIFICATION ----------------------------------------------------------- */
-/* DKIM-Signature: headers are added to the verification list */
-if (ctx->mode == PDKIM_MODE_VERIFY)
- {
- if (strncasecmp(ctx->cur_header->str,
- DKIM_SIGNATURE_HEADERNAME,
- strlen(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->str)))
- {
- 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
- {
- pdkim_stringlist *list;
-
- if (!(list = pdkim_prepend_stringlist(ctx->headers, ctx->cur_header->str)))
- return PDKIM_ERR_OOM;
- ctx->headers = list;
- }
- }
-
-BAIL:
-pdkim_strclear(ctx->cur_header); /* Re-use existing pdkim_str */
-return PDKIM_OK;
-}
-
-
-
-/* -------------------------------------------------------------------------- */
-#define HEADER_BUFFER_FRAG_SIZE 256
-
-DLLEXPORT int
-pdkim_feed (pdkim_ctx *ctx, char *data, int len)
-{
-int p;
-
-for (p = 0; p<len; p++)
- {
- char c = data[p];
-
- if (ctx->past_headers)
- {
- /* 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->seen_lf)
- {
- int rc = pdkim_header_complete(ctx); /* Seen last header line */
- if (rc != PDKIM_OK) return rc;
-
- ctx->past_headers = TRUE;
- ctx->seen_lf = 0;
- DEBUG(D_acl) debug_printf(
- "PDKIM >> Hashed body data, canonicalized >>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
- continue;
- }
- else
- ctx->seen_lf = TRUE;
- }
- else if (ctx->seen_lf)
- {
- if (!(c == '\t' || c == ' '))
- {
- int rc = pdkim_header_complete(ctx); /* End of header */
- if (rc != PDKIM_OK) return rc;
- }
- ctx->seen_lf = FALSE;
- }
- }
-
- if (!ctx->cur_header)
- if (!(ctx->cur_header = pdkim_strnew(NULL)))
- return PDKIM_ERR_OOM;
-
- if (ctx->cur_header->len < PDKIM_MAX_HEADER_LEN)
- if (!pdkim_strncat(ctx->cur_header, &data[p], 1))
- return PDKIM_ERR_OOM;
- }
- }
-return PDKIM_OK;
-}
-
-/*
- * RFC 5322 specifies that header line length SHOULD be no more than 78
- * lets make it so!
- * pdkim_headcat
- * returns char*
- *
- * col: this int holds and receives column number (octets since last '\n')
- * str: partial string to append to
- * 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 char *
-pdkim_headcat(int *col, pdkim_str *str, const char * pad,
- const char *intro, const char *payload)
-{
-size_t l;
-
-if (pad)
- {
- l = strlen(pad);
- if (*col + l > 78)
- {
- pdkim_strcat(str, "\r\n\t");
- *col = 1;
- }
- pdkim_strncat(str, pad, l);
- *col += l;
- }
-
-l = (pad?1:0) + (intro?strlen(intro):0);
-
-if (*col + l > 78)
- { /*can't fit intro - start a new line to make room.*/
- pdkim_strcat(str, "\r\n\t");
- *col = 1;
- l = intro?strlen(intro):0;
- }
-
-l += payload ? strlen(payload):0 ;
-
-while (l>77)
- { /* this fragment will not fit on a single line */
- if (pad)
- {
- pdkim_strcat(str, " ");
- *col += 1;
- pad = NULL; /* only want this once */
- l--;
- }
-
- if (intro)
- {
- size_t sl = strlen(intro);
-
- pdkim_strncat(str, intro, sl);
- *col += sl;
- l -= sl;
- intro = NULL; /* only want this once */
- }
-
- if (payload)
- {
- size_t sl = strlen(payload);
- size_t chomp = *col+sl < 77 ? sl : 78-*col;
-
- pdkim_strncat(str, payload, chomp);
- *col += chomp;
- payload += chomp;
- l -= chomp-1;
- }
-
- /* the while precondition tells us it didn't fit. */
- pdkim_strcat(str, "\r\n\t");
- *col = 1;
- }
-
-if (*col + l > 78)
- {
- pdkim_strcat(str, "\r\n\t");
- *col = 1;
- pad = NULL;
- }
-
-if (pad)
- {
- pdkim_strcat(str, " ");
- *col += 1;
- pad = NULL;
- }
-
-if (intro)
- {
- size_t sl = strlen(intro);
-
- pdkim_strncat(str, intro, sl);
- *col += sl;
- l -= sl;
- intro = NULL;
- }
-
-if (payload)
- {
- size_t sl = strlen(payload);
-
- pdkim_strncat(str, payload, sl);
- *col += sl;
- }
-
-return str->str;
-}
-
-
-/* -------------------------------------------------------------------------- */
-
-static char *
-pdkim_create_header(pdkim_signature *sig, BOOL final)
-{
-char *rc = NULL;
-char *base64_bh = NULL;
-char *base64_b = NULL;
-int col = 0;
-pdkim_str *hdr;
-pdkim_str *canon_all;
-
-if (!(hdr = pdkim_strnew("DKIM-Signature: v="PDKIM_SIGNATURE_VERSION)))
- return NULL;
-
-if (!(canon_all = pdkim_strnew(pdkim_canons[sig->canon_headers])))
- goto BAIL;
-
-if (!(base64_bh = pdkim_encode_base64(&sig->bodyhash)))
- goto BAIL;
-
-col = strlen(hdr->str);
-
-/* Required and static bits */
-if ( pdkim_headcat(&col, hdr, ";", "a=", pdkim_algos[sig->algo])
- && pdkim_headcat(&col, hdr, ";", "q=", pdkim_querymethods[sig->querymethod])
- && pdkim_strcat(canon_all, "/")
- && pdkim_strcat(canon_all, pdkim_canons[sig->canon_body])
- && pdkim_headcat(&col, hdr, ";", "c=", canon_all->str)
- && pdkim_headcat(&col, hdr, ";", "d=", sig->domain)
- && pdkim_headcat(&col, hdr, ";", "s=", sig->selector)
- )
- {
- /* list of header names can be split between items. */
- {
- char *n = CS string_copy(sig->headernames);
- char *f = n;
- char *i = "h=";
- char *s = ";";
-
- if (!n) goto BAIL;
- while (*n)
- {
- char *c = strchr(n, ':');
-
- if (c) *c ='\0';
-
- if (!i)
- if (!pdkim_headcat(&col, hdr, NULL, NULL, ":"))
- goto BAIL;
-
- if (!pdkim_headcat(&col, hdr, s, i, n))
- goto BAIL;
-
- if (!c)
- break;
-
- n = c+1;
- s = NULL;
- i = NULL;
- }
- }
-
- if(!pdkim_headcat(&col, hdr, ";", "bh=", base64_bh))
- goto BAIL;
-
- /* Optional bits */
- if (sig->identity)
- if(!pdkim_headcat(&col, hdr, ";", "i=", sig->identity))
- goto BAIL;
-
- if (sig->created > 0)
- {
- char minibuf[20];
-
- snprintf(minibuf, 20, "%lu", sig->created);
- if(!pdkim_headcat(&col, hdr, ";", "t=", minibuf))
- goto BAIL;
- }
-
- if (sig->expires > 0)
- {
- char minibuf[20];
-
- snprintf(minibuf, 20, "%lu", sig->expires);
- if(!pdkim_headcat(&col, hdr, ";", "x=", minibuf))
- goto BAIL;
- }
-
- if (sig->bodylength >= 0)
- {
- char minibuf[20];
-
- snprintf(minibuf, 20, "%lu", sig->bodylength);
- if(!pdkim_headcat(&col, hdr, ";", "l=", minibuf))
- goto BAIL;
- }
-
- /* Preliminary or final version? */
- if (final)
- {
- if (!(base64_b = pdkim_encode_base64(&sig->sigdata)))
- goto BAIL;
- if (!pdkim_headcat(&col, hdr, ";", "b=", base64_b))
- goto BAIL;
- }
- else
- if(!pdkim_headcat(&col, hdr, ";", "b=", ""))
- goto BAIL;
-
- /* add trailing semicolon: I'm not sure if this is actually needed */
- if (!pdkim_headcat(&col, hdr, NULL, ";", ""))
- goto BAIL;
- }
-
-rc = strdup(hdr->str);
-
-BAIL:
-pdkim_strfree(hdr);
-if (canon_all) pdkim_strfree(canon_all);
-return rc;
-}
-
-
-/* -------------------------------------------------------------------------- */
-
-DLLEXPORT int
-pdkim_feed_finish(pdkim_ctx *ctx, pdkim_signature **return_signatures)
-{
-pdkim_signature *sig = ctx->sig;
-pdkim_str *headernames = NULL; /* Collected signed header names */
-
-/* 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 '<CR><LF>' */
-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 */
-if (pdkim_finish_bodyhash(ctx) != PDKIM_OK)
- return PDKIM_ERR_OOM;
-
-/* SIGNING -------------------------------------------------------------- */
-if (ctx->mode == PDKIM_MODE_SIGN)
- if (!(headernames = pdkim_strnew(NULL)))
- return PDKIM_ERR_OOM;
-/* ---------------------------------------------------------------------- */
-
-while (sig)
- {
- BOOL is_sha1 = sig->algo == PDKIM_ALGO_RSA_SHA1;
- hctx hhash_ctx;
- char * sig_hdr;
- blob hhash;
- blob hdata;
- int hdata_alloc = 0;
-
- hdata.data = NULL;
- hdata.len = 0;
-
- exim_sha_init(&hhash_ctx, is_sha1);
-
- 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. */
-
- if (ctx->mode == PDKIM_MODE_SIGN)
- {
- pdkim_stringlist *p;
-
- for (p = sig->headers; p; p = p->next)
- {
- uschar * rh;
- /* Collect header names (Note: colon presence is guaranteed here) */
- uschar * q = Ustrchr(p->value, ':');
-
- if (!(pdkim_strncat(headernames, p->value,
- (q-US (p->value)) + (p->next ? 1 : 0))))
- return PDKIM_ERR_OOM;
-
- rh = sig->canon_headers == PDKIM_CANON_RELAXED
- ? US pdkim_relax_header(p->value, 1) /* cook header for relaxed canon */
- : string_copy(p->value); /* just copy it for simple canon */
- if (!rh)
- return PDKIM_ERR_OOM;
-
- /* Feed header to the hash algorithm */
- exim_sha_update(&hhash_ctx, rh, strlen(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));
- }
- }
-
- /* 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 * b = string_copy(sig->headernames);
- uschar * p = b;
- uschar * q;
- pdkim_stringlist * hdrs;
-
- if (!b) return PDKIM_ERR_OOM;
-
- /* clear tags */
- for (hdrs = ctx->headers; hdrs; hdrs = hdrs->next)
- hdrs->tag = 0;
-
- while(1)
- {
- if ((q = Ustrchr(p, ':')))
- *q = '\0';
-
- for (hdrs = ctx->headers; hdrs; hdrs = hdrs->next)
- if ( hdrs->tag == 0
- && strncasecmp(hdrs->value, CS p, Ustrlen(p)) == 0
- && (hdrs->value)[Ustrlen(p)] == ':'
- )
- {
- uschar * rh = sig->canon_headers == PDKIM_CANON_RELAXED
- ? US pdkim_relax_header(hdrs->value, 1) /* cook header for relaxed canon */
- : string_copy(hdrs->value); /* just copy it for simple canon */
- if (!rh)
- return PDKIM_ERR_OOM;
-
- /* Feed header to the hash algorithm */
- exim_sha_update(&hhash_ctx, rh, strlen(rh));
-
- DEBUG(D_acl) pdkim_quoteprint(rh, Ustrlen(rh));
- hdrs->tag = 1;
- break;
- }
-
- if (!q) break;
- p = q+1;
- }
- }
-
- DEBUG(D_acl) debug_printf(
- "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
-
- /* SIGNING ---------------------------------------------------------------- */
- if (ctx->mode == PDKIM_MODE_SIGN)
- {
- /* Copy headernames to signature struct */
- sig->headernames = string_copy(US headernames->str);
- pdkim_strfree(headernames);
-
- /* Create signature header with b= omitted */
- sig_hdr = pdkim_create_header(ctx->sig, FALSE);
- }
-
- /* VERIFICATION ----------------------------------------------------------- */
- else
- sig_hdr = strdup(sig->rawsig_no_b_val);
- /* ------------------------------------------------------------------------ */
-
- if (!sig_hdr)
- return PDKIM_ERR_OOM;
-
- /* Relax header if necessary */
- if (sig->canon_headers == PDKIM_CANON_RELAXED)
- {
- char *relaxed_hdr = pdkim_relax_header(sig_hdr, 0);
-
- free(sig_hdr);
- if (!relaxed_hdr)
- return PDKIM_ERR_OOM;
- sig_hdr = relaxed_hdr;
- }
-
- DEBUG(D_acl)
- {
- debug_printf(
- "PDKIM >> Signed DKIM-Signature header, canonicalized >>>>>>>>>>>>>>>>>\n");
- pdkim_quoteprint(sig_hdr, strlen(sig_hdr));
- debug_printf(
- "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
- }
-
- /* Finalize header hash */
- exim_sha_update(&hhash_ctx, sig_hdr, strlen(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->mode == PDKIM_MODE_SIGN)
- (void) exim_rsa_data_append(&hdata, &hdata_alloc, sig_hdr);
-
- free(sig_hdr);
-
- /* SIGNING ---------------------------------------------------------------- */
- if (ctx->mode == PDKIM_MODE_SIGN)
- {
- es_ctx sctx;
- const uschar * errstr;
-
- /* Import private key */
- if ((errstr = exim_rsa_signing_init(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);
- }
-
- if (!(sig->signature_header = pdkim_create_header(ctx->sig, TRUE)))
- return PDKIM_ERR_OOM;
- }
-
- /* VERIFICATION ----------------------------------------------------------- */
- else
- {
- ev_ctx vctx;
- const uschar * errstr;
-
- char *dns_txt_name, *dns_txt_reply;
-
- /* Fetch public key for signing domain, from DNS */
-
- if (!(dns_txt_name = malloc(PDKIM_DNS_TXT_MAX_NAMELEN)))
- return PDKIM_ERR_OOM;
-
- if (!(dns_txt_reply = malloc(PDKIM_DNS_TXT_MAX_RECLEN)))
- {
- free(dns_txt_name);
- return PDKIM_ERR_OOM;
- }
-
- memset(dns_txt_reply, 0, PDKIM_DNS_TXT_MAX_RECLEN);
- memset(dns_txt_name , 0, PDKIM_DNS_TXT_MAX_NAMELEN);
-
- if (snprintf(dns_txt_name, PDKIM_DNS_TXT_MAX_NAMELEN,
- "%s._domainkey.%s.",
- sig->selector, sig->domain) >= PDKIM_DNS_TXT_MAX_NAMELEN)
- {
- sig->verify_status = PDKIM_VERIFY_INVALID;
- sig->verify_ext_status = PDKIM_VERIFY_INVALID_BUFFER_SIZE;
- goto NEXT_VERIFY;
- }
-
- if ( ctx->dns_txt_callback(dns_txt_name, 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(dns_txt_reply, strlen(dns_txt_reply));
- }
-
- if (!(sig->pubkey = pdkim_parse_pubkey_record(ctx, 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");
- }
-
- free(dns_txt_name);
- free(dns_txt_reply);
- }
-
- 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 *))
-{
-pdkim_ctx *ctx = malloc(sizeof(pdkim_ctx));
-
-if (!ctx)
- return NULL;
-memset(ctx, 0, sizeof(pdkim_ctx));
-
-if (!(ctx->linebuf = malloc(PDKIM_MAX_BODY_LINE_LEN)))
- {
- free(ctx);
- return NULL;
- }
-
-ctx->mode = PDKIM_MODE_VERIFY;
-ctx->dns_txt_callback = dns_txt_callback;
-
-return ctx;
-}
-
-
-/* -------------------------------------------------------------------------- */
-
-DLLEXPORT pdkim_ctx *
-pdkim_init_sign(char *domain, char *selector, char *rsa_privkey, int algo)
-{
-pdkim_ctx *ctx;
-pdkim_signature *sig;
-
-if (!domain || !selector || !rsa_privkey)
- return NULL;
-
-if (!(ctx = malloc(sizeof(pdkim_ctx))))
- return NULL;
-memset(ctx, 0, sizeof(pdkim_ctx));
-
-if (!(ctx->linebuf = malloc(PDKIM_MAX_BODY_LINE_LEN)))
- {
- free(ctx);
- return NULL;
- }
-
-if (!(sig = malloc(sizeof(pdkim_signature))))
- {
- free(ctx->linebuf);
- free(ctx);
- return NULL;
- }
-memset(sig, 0, sizeof(pdkim_signature));
-
-sig->bodylength = -1;
-
-ctx->mode = PDKIM_MODE_SIGN;
-ctx->sig = sig;
-
-sig->domain = strdup(domain);
-sig->selector = strdup(selector);
-sig->rsa_privkey = strdup(rsa_privkey);
-sig->algo = algo;
-
-if (!sig->domain || !sig->selector || !sig->rsa_privkey)
- goto BAIL;
-
-exim_sha_init(&sig->body_hash, algo == PDKIM_ALGO_RSA_SHA1);
-return ctx;
-
-BAIL:
- pdkim_free_ctx(ctx);
- return NULL;
-}
-
-
-/* -------------------------------------------------------------------------- */
-
-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)
-{
-if (identity)
- if (!(ctx->sig->identity = strdup(identity)))
- return PDKIM_ERR_OOM;
-
-if (sign_headers)
- if (!(ctx->sig->sign_headers = strdup(sign_headers)))
- return PDKIM_ERR_OOM;
-
-ctx->sig->canon_headers = canon_headers;
-ctx->sig->canon_body = canon_body;
-ctx->sig->bodylength = bodylength;
-ctx->sig->created = created;
-ctx->sig->expires = expires;
-
-return PDKIM_OK;
-}
-
-
-void
-pdkim_init(void)
-{
-exim_rsa_init();
-}
-
-
-
-#endif /*DISABLE_DKIM*/
git://git.exim.org / exim.git / blobdiff