+++ /dev/null
-/*
- * PDKIM - a RFC4871 (DKIM) implementation
- *
- * Copyright (C) 2009 Tom Kistner <tom@duncanthrax.net>
- *
- * 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.
- */
-
-/* $Cambridge: exim/src/src/pdkim/pdkim.c,v 1.9 2009/11/19 18:52:48 nm4 Exp $ */
-
-#include <stdlib.h>
-#include <stdio.h>
-#include <string.h>
-#include <ctype.h>
-
-#include "pdkim.h"
-
-#include "sha1.h"
-#include "sha2.h"
-#include "rsa.h"
-#include "base64.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;
- void *next;
-};
-
-#define PDKIM_STR_ALLOC_FRAG 256
-struct pdkim_str {
- char *str;
- unsigned int len;
- unsigned int allocated;
-};
-
-/* -------------------------------------------------------------------------- */
-/* A bunch of list constants */
-char *pdkim_querymethods[] = {
- "dns/txt",
- NULL
-};
-char *pdkim_algos[] = {
- "rsa-sha256",
- "rsa-sha1",
- NULL
-};
-char *pdkim_canons[] = {
- "simple",
- "relaxed",
- NULL
-};
-char *pdkim_hashes[] = {
- "sha256",
- "sha1",
- NULL
-};
-char *pdkim_keytypes[] = {
- "rsa",
- NULL
-};
-
-typedef struct pdkim_combined_canon_entry {
- 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 }
-};
-
-
-/* -------------------------------------------------------------------------- */
-/* Print debugging functions */
-#ifdef PDKIM_DEBUG
-void pdkim_quoteprint(FILE *stream, char *data, int len, int lf) {
- int i;
- unsigned char *p = (unsigned char *)data;
-
- for (i=0;i<len;i++) {
- int c = p[i];
- switch (c) {
- case ' ' : fprintf(stream,"{SP}"); break;
- case '\t': fprintf(stream,"{TB}"); break;
- case '\r': fprintf(stream,"{CR}"); break;
- case '\n': fprintf(stream,"{LF}"); break;
- case '{' : fprintf(stream,"{BO}"); break;
- case '}' : fprintf(stream,"{BC}"); break;
- default:
- if ( (c < 32) || (c > 127) )
- fprintf(stream,"{%02x}",c);
- else
- fputc(c,stream);
- break;
- }
- }
- if (lf)
- fputc('\n',stream);
-}
-void pdkim_hexprint(FILE *stream, char *data, int len, int lf) {
- int i;
- unsigned char *p = (unsigned char *)data;
-
- for (i=0;i<len;i++) {
- int c = p[i];
- fprintf(stream,"%02x",c);
- }
- if (lf)
- fputc('\n',stream);
-}
-#endif
-
-
-/* -------------------------------------------------------------------------- */
-/* Simple string list implementation for convinience */
-pdkim_stringlist *pdkim_append_stringlist(pdkim_stringlist *base, char *str) {
- pdkim_stringlist *new_entry = malloc(sizeof(pdkim_stringlist));
- if (new_entry == NULL) return NULL;
- memset(new_entry,0,sizeof(pdkim_stringlist));
- new_entry->value = strdup(str);
- if (new_entry->value == NULL) return NULL;
- if (base != NULL) {
- pdkim_stringlist *last = base;
- while (last->next != NULL) { last = last->next; }
- last->next = new_entry;
- return base;
- }
- else return new_entry;
-}
-pdkim_stringlist *pdkim_prepend_stringlist(pdkim_stringlist *base, char *str) {
- pdkim_stringlist *new_entry = malloc(sizeof(pdkim_stringlist));
- if (new_entry == NULL) return NULL;
- memset(new_entry,0,sizeof(pdkim_stringlist));
- new_entry->value = strdup(str);
- if (new_entry->value == NULL) return NULL;
- if (base != NULL) {
- new_entry->next = base;
- }
- return new_entry;
-}
-
-
-/* -------------------------------------------------------------------------- */
-/* A small "growing string" implementation to escape malloc/realloc hell */
-pdkim_str *pdkim_strnew (char *cstr) {
- unsigned int len = cstr?strlen(cstr):0;
- pdkim_str *p = malloc(sizeof(pdkim_str));
- if (p == NULL) return NULL;
- memset(p,0,sizeof(pdkim_str));
- p->str = malloc(len+1);
- if (p->str == NULL) {
- free(p);
- return NULL;
- }
- p->allocated=(len+1);
- p->len=len;
- if (cstr) strcpy(p->str,cstr);
- return p;
-}
-char *pdkim_strncat(pdkim_str *str, 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;
-}
-char *pdkim_strcat(pdkim_str *str, char *cstr) {
- return pdkim_strncat(str, cstr, strlen(cstr));
-}
-char *pdkim_numcat(pdkim_str *str, unsigned long num) {
- char minibuf[20];
- snprintf(minibuf,20,"%lu",num);
- return pdkim_strcat(str,minibuf);
-}
-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;
-}
-char *pdkim_strclear(pdkim_str *str) {
- str->str[0] = '\0';
- str->len = 0;
- return str->str;
-}
-void pdkim_strfree(pdkim_str *str) {
- if (str == NULL) return;
- if (str->str != NULL) free(str->str);
- free(str);
-}
-
-
-
-/* -------------------------------------------------------------------------- */
-void pdkim_free_pubkey(pdkim_pubkey *pub) {
- if (pub) {
- if (pub->version != NULL) free(pub->version);
- if (pub->granularity != NULL) free(pub->granularity);
- if (pub->hashes != NULL) free(pub->hashes);
- if (pub->keytype != NULL) free(pub->keytype);
- if (pub->srvtype != NULL) free(pub->srvtype);
- if (pub->notes != NULL) free(pub->notes);
- if (pub->key != NULL) free(pub->key);
- free(pub);
- }
-}
-
-
-/* -------------------------------------------------------------------------- */
-void pdkim_free_sig(pdkim_signature *sig) {
- if (sig) {
- pdkim_signature *next = (pdkim_signature *)sig->next;
-
- pdkim_stringlist *e = sig->headers;
- while(e != NULL) {
- pdkim_stringlist *c = e;
- if (e->value != NULL) free(e->value);
- e = e->next;
- free(c);
- }
-
- if (sig->sigdata != NULL) free(sig->sigdata);
- if (sig->bodyhash != NULL) free(sig->bodyhash);
- if (sig->selector != NULL) free(sig->selector);
- if (sig->domain != NULL) free(sig->domain);
- if (sig->identity != NULL) free(sig->identity);
- if (sig->headernames != NULL) free(sig->headernames);
- if (sig->copiedheaders != NULL) free(sig->copiedheaders);
- if (sig->rsa_privkey != NULL) free(sig->rsa_privkey);
- if (sig->sign_headers != NULL) free(sig->sign_headers);
- if (sig->signature_header != NULL) free(sig->signature_header);
- if (sig->sha1_body != NULL) free(sig->sha1_body);
- if (sig->sha2_body != NULL) free(sig->sha2_body);
- if (sig->hnames_check != NULL) free(sig->hnames_check);
-
- if (sig->pubkey != NULL) pdkim_free_pubkey(sig->pubkey);
-
- free(sig);
- if (next != NULL) pdkim_free_sig(next);
- }
-}
-
-
-/* -------------------------------------------------------------------------- */
-DLLEXPORT void pdkim_free_ctx(pdkim_ctx *ctx) {
- if (ctx) {
- 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. */
-int header_name_match(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 == NULL) return rc; /* This isn't a header */
- hname = malloc((hcolon-header)+1);
- if (hname == NULL) 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 */
- lcopy = strdup(tick);
- if (lcopy == NULL) {
- free(hname);
- return PDKIM_ERR_OOM;
- }
- p = lcopy;
- q = strchr(p,':');
- while (q != NULL) {
- *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. */
-char *pdkim_relax_header (char *header, int crlf) {
- int past_field_name = 0;
- int seen_wsp = 0;
- char *p = header;
- char *q;
- char *relaxed = malloc(strlen(header)+3);
- if (relaxed == NULL) return NULL;
- q = relaxed;
- while (*p != '\0') {
- int c = *p;
- /* Ignore CR & LF */
- if ( (c == '\r') || (c == '\n') ) {
- p++;
- continue;
- }
- if ( (c == '\t') || (c == ' ') ) {
- c = ' '; /* Turns WSP into SP */
- if (seen_wsp) {
- p++;
- continue;
- }
- else seen_wsp = 1;
- }
- else {
- if ( (!past_field_name) && (c == ':') ) {
- if (seen_wsp) q--; /* This removes WSP before the colon */
- seen_wsp = 1; /* This removes WSP after the colon */
- past_field_name = 1;
- }
- else seen_wsp = 0;
- }
- /* Lowercase header name */
- if (!past_field_name) c = tolower(c);
- *q = c;
- p++;
- q++;
- }
- *q = '\0';
- if (crlf) strcat(relaxed,"\r\n");
- return relaxed;
-}
-
-
-/* -------------------------------------------------------------------------- */
-#define PDKIM_QP_ERROR_DECODE -1
-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 */
- if (isdigit(*qp_p)) {*c = *qp_p - '0';}
- else {*c = toupper(*qp_p) - 'A' + 10;}
- *c <<= 4;
- if (isdigit(qp_p[1])) {*c |= qp_p[1] - '0';}
- else {*c |= toupper(qp_p[1]) - 'A' + 10;}
- return qp_p + 2;
- }
-
- /* Illegal char here */
- *c = PDKIM_QP_ERROR_DECODE;
- return initial_pos;
-}
-
-
-/* -------------------------------------------------------------------------- */
-char *pdkim_decode_qp(char *str) {
- int nchar = 0;
- char *q;
- char *p = str;
- char *n = malloc(strlen(p)+1);
- if (n == NULL) return NULL;
- *n = '\0';
- q = n;
- while (*p != '\0') {
- if (*p == '=') {
- p = pdkim_decode_qp_char(p,&nchar);
- if (nchar >= 0) {
- *q = nchar;
- q++;
- continue;
- }
- }
- else {
- *q = *p;
- q++;
- }
- p++;
- }
- *q = '\0';
- return n;
-}
-
-
-/* -------------------------------------------------------------------------- */
-char *pdkim_decode_base64(char *str, int *num_decoded) {
- int dlen = 0;
- char *res;
-
- base64_decode(NULL, &dlen, (unsigned char *)str, strlen(str));
- res = malloc(dlen+1);
- if (res == NULL) return NULL;
- if (base64_decode((unsigned char *)res,&dlen,(unsigned char *)str,strlen(str)) != 0) {
- free(res);
- return NULL;
- }
- if (num_decoded != NULL) *num_decoded = dlen;
- return res;
-}
-
-/* -------------------------------------------------------------------------- */
-char *pdkim_encode_base64(char *str, int num) {
- int dlen = 0;
- char *res;
-
- base64_encode(NULL, &dlen, (unsigned char *)str, num);
- res = malloc(dlen+1);
- if (res == NULL) return NULL;
- if (base64_encode((unsigned char *)res,&dlen,(unsigned char *)str,num) != 0) {
- free(res);
- return NULL;
- }
- return res;
-}
-
-
-/* -------------------------------------------------------------------------- */
-#define PDKIM_HDR_LIMBO 0
-#define PDKIM_HDR_TAG 1
-#define PDKIM_HDR_VALUE 2
-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;
- int past_hname = 0;
- int in_b_val = 0;
- int where = PDKIM_HDR_LIMBO;
- int i;
-
- sig = malloc(sizeof(pdkim_signature));
- if (sig == NULL) return NULL;
- memset(sig,0,sizeof(pdkim_signature));
- sig->bodylength = -1;
-
- sig->rawsig_no_b_val = malloc(strlen(raw_hdr)+1);
- if (sig->rawsig_no_b_val == NULL) {
- free(sig);
- return NULL;
- }
-
- p = raw_hdr;
- q = sig->rawsig_no_b_val;
-
- while (1) {
-
- /* Ignore FWS */
- if ( (*p == '\r') || (*p == '\n') )
- goto NEXT_CHAR;
-
- /* Fast-forward through header name */
- if (!past_hname) {
- if (*p == ':') past_hname = 1;
- goto NEXT_CHAR;
- }
-
- if (where == PDKIM_HDR_LIMBO) {
- /* In limbo, just wait for a tag-char to appear */
- if (!((*p >= 'a') && (*p <= 'z')))
- goto NEXT_CHAR;
-
- where = PDKIM_HDR_TAG;
- }
-
- if (where == PDKIM_HDR_TAG) {
- if (cur_tag == NULL)
- cur_tag = pdkim_strnew(NULL);
-
- if ((*p >= 'a') && (*p <= 'z'))
- pdkim_strncat(cur_tag,p,1);
-
- if (*p == '=') {
- if (strcmp(cur_tag->str,"b") == 0) {
- *q = '='; q++;
- in_b_val = 1;
- }
- where = PDKIM_HDR_VALUE;
- goto NEXT_CHAR;
- }
- }
-
- if (where == PDKIM_HDR_VALUE) {
- if (cur_val == NULL)
- cur_val = pdkim_strnew(NULL);
-
- if ( (*p == '\r') || (*p == '\n') || (*p == ' ') || (*p == '\t') )
- goto NEXT_CHAR;
-
- if ( (*p == ';') || (*p == '\0') ) {
- if (cur_tag->len > 0) {
- pdkim_strtrim(cur_val);
- #ifdef PDKIM_DEBUG
- if (ctx->debug_stream)
- fprintf(ctx->debug_stream, "%s=%s\n", cur_tag->str, cur_val->str);
- #endif
- switch (cur_tag->str[0]) {
- case 'b':
- switch (cur_tag->str[1]) {
- case 'h':
- sig->bodyhash = pdkim_decode_base64(cur_val->str,&(sig->bodyhash_len));
- break;
- default:
- sig->sigdata = pdkim_decode_base64(cur_val->str,&(sig->sigdata_len));
- break;
- }
- break;
- case 'v':
- if (strcmp(cur_val->str,PDKIM_SIGNATURE_VERSION) == 0) {
- /* We only support version 1, and that is currently the
- only version there is. */
- sig->version = 1;
- }
- break;
- case 'a':
- i = 0;
- while (pdkim_algos[i] != NULL) {
- if (strcmp(cur_val->str,pdkim_algos[i]) == 0 ) {
- sig->algo = i;
- break;
- }
- i++;
- }
- break;
- case 'c':
- i = 0;
- while (pdkim_combined_canons[i].str != NULL) {
- 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;
- }
- i++;
- }
- break;
- case 'q':
- i = 0;
- while (pdkim_querymethods[i] != NULL) {
- if (strcmp(cur_val->str,pdkim_querymethods[i]) == 0 ) {
- sig->querymethod = i;
- break;
- }
- i++;
- }
- 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 = strdup(cur_val->str);
- break;
- case 'z':
- sig->copiedheaders = pdkim_decode_qp(cur_val->str);
- break;
- default:
- #ifdef PDKIM_DEBUG
- if (ctx->debug_stream)
- fprintf(ctx->debug_stream, "Unknown tag encountered\n");
- #endif
- break;
- }
- }
- pdkim_strclear(cur_tag);
- pdkim_strclear(cur_val);
- in_b_val = 0;
- where = PDKIM_HDR_LIMBO;
- goto NEXT_CHAR;
- }
- else pdkim_strncat(cur_val,p,1);
- }
-
- NEXT_CHAR:
- if (*p == '\0') break;
-
- if (!in_b_val) {
- *q = *p;
- q++;
- }
- p++;
- }
-
- /* 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->bodyhash &&
- sig->sigdata &&
- sig->version)) {
- pdkim_free_sig(sig);
- return NULL;
- }
-
- /* Copy header list to 'tick-off' header list */
- sig->hnames_check = strdup(sig->headernames);
-
- *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--;
- }
-
- #ifdef PDKIM_DEBUG
- if (ctx->debug_stream) {
- fprintf(ctx->debug_stream,
- "PDKIM >> Raw signature w/o b= tag value >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
- pdkim_quoteprint(ctx->debug_stream,
- sig->rawsig_no_b_val,
- strlen(sig->rawsig_no_b_val), 1);
- fprintf(ctx->debug_stream,
- "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
- }
- #endif
-
- sig->sha1_body = malloc(sizeof(sha1_context));
- if (sig->sha1_body == NULL) {
- pdkim_free_sig(sig);
- return NULL;
- }
- sig->sha2_body = malloc(sizeof(sha2_context));
- if (sig->sha2_body == NULL) {
- pdkim_free_sig(sig);
- return NULL;
- }
-
- sha1_starts(sig->sha1_body);
- sha2_starts(sig->sha2_body,0);
-
- return sig;
-}
-
-
-/* -------------------------------------------------------------------------- */
-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;
-
- pub = malloc(sizeof(pdkim_pubkey));
- if (pub == NULL) return NULL;
- memset(pub,0,sizeof(pdkim_pubkey));
-
- p = raw_record;
-
- while (1) {
-
- /* Ignore FWS */
- if ( (*p == '\r') || (*p == '\n') )
- goto NEXT_CHAR;
-
- if (where == PDKIM_HDR_LIMBO) {
- /* In limbo, just wait for a tag-char to appear */
- if (!((*p >= 'a') && (*p <= 'z')))
- goto NEXT_CHAR;
-
- where = PDKIM_HDR_TAG;
- }
-
- if (where == PDKIM_HDR_TAG) {
- if (cur_tag == NULL)
- cur_tag = pdkim_strnew(NULL);
-
- if ((*p >= 'a') && (*p <= 'z'))
- pdkim_strncat(cur_tag,p,1);
-
- if (*p == '=') {
- where = PDKIM_HDR_VALUE;
- goto NEXT_CHAR;
- }
- }
-
- if (where == PDKIM_HDR_VALUE) {
- if (cur_val == NULL)
- cur_val = pdkim_strnew(NULL);
-
- if ( (*p == '\r') || (*p == '\n') )
- goto NEXT_CHAR;
-
- if ( (*p == ';') || (*p == '\0') ) {
- if (cur_tag->len > 0) {
- pdkim_strtrim(cur_val);
- #ifdef PDKIM_DEBUG
- if (ctx->debug_stream)
- fprintf(ctx->debug_stream, "%s=%s\n", cur_tag->str, cur_val->str);
- #endif
- 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':
- pub->key = pdkim_decode_base64(cur_val->str,&(pub->key_len));
- 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,'t') != NULL) pub->testing = 1;
- if (strchr(cur_val->str,'s') != NULL) pub->no_subdomaining = 1;
- break;
- default:
- #ifdef PDKIM_DEBUG
- if (ctx->debug_stream)
- fprintf(ctx->debug_stream, "Unknown tag encountered\n");
- #endif
- break;
- }
- }
- pdkim_strclear(cur_tag);
- pdkim_strclear(cur_val);
- where = PDKIM_HDR_LIMBO;
- goto NEXT_CHAR;
- }
- else pdkim_strncat(cur_val,p,1);
- }
-
- NEXT_CHAR:
- if (*p == '\0') break;
- p++;
- }
-
- /* Set fallback defaults */
- if (pub->version == NULL) pub->version = strdup(PDKIM_PUB_RECORD_VERSION);
- if (pub->granularity == NULL) pub->granularity = strdup("*");
- if (pub->keytype == NULL) pub->keytype = strdup("rsa");
- if (pub->srvtype == NULL) pub->srvtype = strdup("*");
-
- /* p= is required */
- if (pub->key == NULL) {
- pdkim_free_pubkey(pub);
- return NULL;
- }
-
- return pub;
-}
-
-
-/* -------------------------------------------------------------------------- */
-int pdkim_update_bodyhash(pdkim_ctx *ctx, 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 != NULL) {
- /* Defaults to simple canon (no further treatment necessary) */
- 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 == NULL) {
- int seen_wsp = 0;
- char *p = data;
- int q = 0;
- relaxed_data = malloc(len+1);
- if (relaxed_data == NULL) return PDKIM_ERR_OOM;
- while (*p != '\0') {
- 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) {
- p++;
- continue;
- }
- else seen_wsp = 1;
- }
- else seen_wsp = 0;
- relaxed_data[q++] = c;
- p++;
- }
- 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) {
- if (sig->algo == PDKIM_ALGO_RSA_SHA1)
- sha1_update(sig->sha1_body,(unsigned char *)canon_data,canon_len);
- else
- sha2_update(sig->sha2_body,(unsigned char *)canon_data,canon_len);
- sig->signed_body_bytes += canon_len;
-#ifdef PDKIM_DEBUG
- if (ctx->debug_stream!=NULL)
- pdkim_quoteprint(ctx->debug_stream,canon_data,canon_len,0);
-#endif
- }
-
- sig = sig->next;
- }
-
- if (relaxed_data != NULL) free(relaxed_data);
- return PDKIM_OK;
-}
-
-
-/* -------------------------------------------------------------------------- */
-int pdkim_finish_bodyhash(pdkim_ctx *ctx) {
- pdkim_signature *sig = ctx->sig;
-
- /* Traverse all signatures */
- while (sig != NULL) {
-
- /* Finish hashes */
- unsigned char bh[32]; /* SHA-256 = 32 Bytes, SHA-1 = 20 Bytes */
- if (sig->algo == PDKIM_ALGO_RSA_SHA1)
- sha1_finish(sig->sha1_body,bh);
- else
- sha2_finish(sig->sha2_body,bh);
-
- #ifdef PDKIM_DEBUG
- if (ctx->debug_stream) {
- fprintf(ctx->debug_stream, "PDKIM [%s] Body bytes hashed: %lu\n",
- sig->domain, sig->signed_body_bytes);
- fprintf(ctx->debug_stream, "PDKIM [%s] bh computed: ", sig->domain);
- pdkim_hexprint(ctx->debug_stream, (char *)bh,
- (sig->algo == PDKIM_ALGO_RSA_SHA1)?20:32,1);
- }
- #endif
-
- /* SIGNING -------------------------------------------------------------- */
- if (ctx->mode == PDKIM_MODE_SIGN) {
- sig->bodyhash_len = (sig->algo == PDKIM_ALGO_RSA_SHA1)?20:32;
- sig->bodyhash = malloc(sig->bodyhash_len);
- if (sig->bodyhash == NULL) return PDKIM_ERR_OOM;
- memcpy(sig->bodyhash,bh,sig->bodyhash_len);
-
- /* 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,sig->bodyhash,
- (sig->algo == PDKIM_ALGO_RSA_SHA1)?20:32) == 0) {
- #ifdef PDKIM_DEBUG
- if (ctx->debug_stream)
- fprintf(ctx->debug_stream, "PDKIM [%s] Body hash verified OK\n",
- sig->domain);
- #endif
- }
- else {
- #ifdef PDKIM_DEBUG
- if (ctx->debug_stream) {
- fprintf(ctx->debug_stream, "PDKIM [%s] Body hash did NOT verify\n",
- sig->domain);
- fprintf(ctx->debug_stream, "PDKIM [%s] bh signature: ", sig->domain);
- pdkim_hexprint(ctx->debug_stream, sig->bodyhash,
- (sig->algo == PDKIM_ALGO_RSA_SHA1)?20:32,1);
- }
- #endif
- sig->verify_status = PDKIM_VERIFY_FAIL;
- sig->verify_ext_status = PDKIM_VERIFY_FAIL_BODY;
- }
- }
-
- sig = sig->next;
- }
-
- return PDKIM_OK;
-}
-
-
-
-/* -------------------------------------------------------------------------- */
-/* Callback from pdkim_feed below for processing complete body lines */
-int pdkim_bodyline_complete(pdkim_ctx *ctx) {
- char *p = ctx->linebuf;
- int n = ctx->linebuf_offset;
-
- /* 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';
-
- if (ctx->input_mode == PDKIM_INPUT_SMTP) {
- /* Terminate on EOD marker */
- if (memcmp(p,".\r\n",3) == 0) {
- ctx->seen_eod = 1;
- 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;
- }
-
- /* 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:"
-int pdkim_header_complete(pdkim_ctx *ctx) {
- pdkim_signature *sig = ctx->sig;
-
- /* 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;
-
- /* Traverse all signatures */
- while (sig != NULL) {
- pdkim_stringlist *list;
-
- /* SIGNING -------------------------------------------------------------- */
- if (ctx->mode == PDKIM_MODE_SIGN) {
- if (header_name_match(ctx->cur_header->str,
- sig->sign_headers?
- sig->sign_headers:
- PDKIM_DEFAULT_SIGN_HEADERS, 0) != PDKIM_OK) goto NEXT_SIG;
- }
- /* VERIFICATION --------------------------------------------------------- */
- else {
- /* Header is not included or all instances were already 'ticked off' */
- if (header_name_match(ctx->cur_header->str,
- sig->hnames_check, 1) != PDKIM_OK) goto NEXT_SIG;
- }
-
- /* Add header to the signed headers list (in reverse order) */
- list = pdkim_prepend_stringlist(sig->headers,
- ctx->cur_header->str);
- if (list == NULL) return PDKIM_ERR_OOM;
- sig->headers = list;
-
- NEXT_SIG:
- sig = sig->next;
- }
-
- /* DKIM-Signature: headers are added to the verification list */
- if ( (ctx->mode == PDKIM_MODE_VERIFY) &&
- (strncasecmp(ctx->cur_header->str,
- DKIM_SIGNATURE_HEADERNAME,
- strlen(DKIM_SIGNATURE_HEADERNAME)) == 0) ) {
- pdkim_signature *new_sig;
- /* Create and chain new signature block */
- #ifdef PDKIM_DEBUG
- if (ctx->debug_stream)
- fprintf(ctx->debug_stream,
- "PDKIM >> Found sig, trying to parse >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
- #endif
- new_sig = pdkim_parse_sig_header(ctx, ctx->cur_header->str);
- if (new_sig != NULL) {
- pdkim_signature *last_sig = ctx->sig;
- if (last_sig == NULL) {
- ctx->sig = new_sig;
- }
- else {
- while (last_sig->next != NULL) { last_sig = last_sig->next; }
- last_sig->next = new_sig;
- }
- }
- else {
- #ifdef PDKIM_DEBUG
- if (ctx->debug_stream) {
- fprintf(ctx->debug_stream,"Error while parsing signature header\n");
- fprintf(ctx->debug_stream,
- "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
- }
- #endif
- }
- }
-
- 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 = 1;
- ctx->seen_lf = 0;
-#ifdef PDKIM_DEBUG
- if (ctx->debug_stream)
- fprintf(ctx->debug_stream,
- "PDKIM >> Hashed body data, canonicalized >>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
-#endif
- continue;
- }
- else ctx->seen_lf = 1;
- }
- 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 = 0;
- }
- }
- if (ctx->cur_header == NULL) {
- ctx->cur_header = pdkim_strnew(NULL);
- if (ctx->cur_header == NULL) return PDKIM_ERR_OOM;
- }
- if (ctx->cur_header->len < PDKIM_MAX_HEADER_LEN)
- if (pdkim_strncat(ctx->cur_header,&data[p],1) == NULL)
- return PDKIM_ERR_OOM;
- }
- }
- return PDKIM_OK;
-}
-
-
-/* -------------------------------------------------------------------------- */
-char *pdkim_create_header(pdkim_signature *sig, int final) {
- char *rc = NULL;
- char *base64_bh = NULL;
- char *base64_b = NULL;
- pdkim_str *hdr = pdkim_strnew("DKIM-Signature: v="PDKIM_SIGNATURE_VERSION);
- if (hdr == NULL) return NULL;
-
- base64_bh = pdkim_encode_base64(sig->bodyhash, sig->bodyhash_len);
- if (base64_bh == NULL) goto BAIL;
-
- /* Required and static bits */
- if (
- pdkim_strcat(hdr,"; a=") &&
- pdkim_strcat(hdr,pdkim_algos[sig->algo]) &&
- pdkim_strcat(hdr,"; q=") &&
- pdkim_strcat(hdr,pdkim_querymethods[sig->querymethod]) &&
- pdkim_strcat(hdr,"; c=") &&
- pdkim_strcat(hdr,pdkim_canons[sig->canon_headers]) &&
- pdkim_strcat(hdr,"/") &&
- pdkim_strcat(hdr,pdkim_canons[sig->canon_body]) &&
- pdkim_strcat(hdr,"; d=") &&
- pdkim_strcat(hdr,sig->domain) &&
- pdkim_strcat(hdr,"; s=") &&
- pdkim_strcat(hdr,sig->selector) &&
- pdkim_strcat(hdr,";\r\n\th=") &&
- pdkim_strcat(hdr,sig->headernames) &&
- pdkim_strcat(hdr,"; bh=") &&
- pdkim_strcat(hdr,base64_bh) &&
- pdkim_strcat(hdr,";\r\n\t")
- ) {
- /* Optional bits */
- if (sig->identity != NULL) {
- if (!( pdkim_strcat(hdr,"i=") &&
- pdkim_strcat(hdr,sig->identity) &&
- pdkim_strcat(hdr,";") ) ) {
- goto BAIL;
- }
- }
- if (sig->created > 0) {
- if (!( pdkim_strcat(hdr,"t=") &&
- pdkim_numcat(hdr,sig->created) &&
- pdkim_strcat(hdr,";") ) ) {
- goto BAIL;
- }
- }
- if (sig->expires > 0) {
- if (!( pdkim_strcat(hdr,"x=") &&
- pdkim_numcat(hdr,sig->expires) &&
- pdkim_strcat(hdr,";") ) ) {
- goto BAIL;
- }
- }
- if (sig->bodylength >= 0) {
- if (!( pdkim_strcat(hdr,"l=") &&
- pdkim_numcat(hdr,sig->bodylength) &&
- pdkim_strcat(hdr,";") ) ) {
- goto BAIL;
- }
- }
- /* Extra linebreak */
- if (hdr->str[(hdr->len)-1] == ';') {
- if (!pdkim_strcat(hdr," \r\n\t")) goto BAIL;
- }
- /* Preliminary or final version? */
- if (final) {
- base64_b = pdkim_encode_base64(sig->sigdata, sig->sigdata_len);
- if (base64_b == NULL) goto BAIL;
- if (
- pdkim_strcat(hdr,"b=") &&
- pdkim_strcat(hdr,base64_b) &&
- pdkim_strcat(hdr,";")
- ) goto DONE;
- }
- else {
- if (pdkim_strcat(hdr,"b=;")) goto DONE;
- }
-
- goto BAIL;
- }
-
- DONE:
- rc = strdup(hdr->str);
-
- BAIL:
- pdkim_strfree(hdr);
- if (base64_bh != NULL) free(base64_bh);
- if (base64_b != NULL) free(base64_b);
- 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 {
- /* For non-smtp input, check if there's an unfinished line in the
- body line buffer. If that is the case, we must add a CRLF to the
- hash to properly terminate the message. */
- if ((ctx->input_mode == PDKIM_INPUT_NORMAL) && ctx->linebuf_offset) {
- pdkim_update_bodyhash(ctx, ctx->linebuf, ctx->linebuf_offset);
- pdkim_update_bodyhash(ctx,"\r\n",2);
- }
- #ifdef PDKIM_DEBUG
- if (ctx->debug_stream)
- fprintf(ctx->debug_stream,
- "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
- #endif
- }
-
- /* Build (and/or evaluate) body hash */
- if (pdkim_finish_bodyhash(ctx) != PDKIM_OK) return PDKIM_ERR_OOM;
-
- /* SIGNING -------------------------------------------------------------- */
- if (ctx->mode == PDKIM_MODE_SIGN) {
- headernames = pdkim_strnew(NULL);
- if (headernames == NULL) return PDKIM_ERR_OOM;
- }
- /* ---------------------------------------------------------------------- */
-
- while (sig != NULL) {
- sha1_context sha1_headers;
- sha2_context sha2_headers;
- char *sig_hdr;
- char headerhash[32];
-
- if (sig->algo == PDKIM_ALGO_RSA_SHA1)
- sha1_starts(&sha1_headers);
- else
- sha2_starts(&sha2_headers,0);
-
- #ifdef PDKIM_DEBUG
- if (ctx->debug_stream)
- fprintf(ctx->debug_stream,
- "PDKIM >> Hashed header data, canonicalized, in sequence >>>>>>>>>>>>>>\n");
- #endif
-
- /* 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 = sig->headers;
- while (p != NULL) {
- char *rh = NULL;
- /* Collect header names (Note: colon presence is guaranteed here) */
- char *q = strchr(p->value,':');
- if (pdkim_strncat(headernames, p->value,
- (q-(p->value))+((p->next==NULL)?0:1)) == NULL)
- return PDKIM_ERR_OOM;
-
- if (sig->canon_headers == PDKIM_CANON_RELAXED)
- rh = pdkim_relax_header(p->value,1); /* cook header for relaxed canon */
- else
- rh = strdup(p->value); /* just copy it for simple canon */
-
- if (rh == NULL) return PDKIM_ERR_OOM;
-
- /* Feed header to the hash algorithm */
- if (sig->algo == PDKIM_ALGO_RSA_SHA1)
- sha1_update(&(sha1_headers),(unsigned char *)rh,strlen(rh));
- else
- sha2_update(&(sha2_headers),(unsigned char *)rh,strlen(rh));
- #ifdef PDKIM_DEBUG
- if (ctx->debug_stream)
- pdkim_quoteprint(ctx->debug_stream, rh, strlen(rh), 1);
- #endif
- free(rh);
- p = p->next;
- }
- }
- /* VERIFICATION ----------------------------------------------------------- */
- /* When verifying, walk through the header name list in the h= parameter and
- add the headers to the hash in that order. */
- else {
- char *b = strdup(sig->headernames);
- char *p = b;
- char *q = NULL;
- if (b == NULL) return PDKIM_ERR_OOM;
-
- while(1) {
- pdkim_stringlist *hdrs = sig->headers;
- q = strchr(p,':');
- if (q != NULL) *q = '\0';
- while (hdrs != NULL) {
- if ( (strncasecmp(hdrs->value,p,strlen(p)) == 0) &&
- ((hdrs->value)[strlen(p)] == ':') ) {
- char *rh = NULL;
- if (sig->canon_headers == PDKIM_CANON_RELAXED)
- rh = pdkim_relax_header(hdrs->value,1); /* cook header for relaxed canon */
- else
- rh = strdup(hdrs->value); /* just copy it for simple canon */
- if (rh == NULL) return PDKIM_ERR_OOM;
- /* Feed header to the hash algorithm */
- if (sig->algo == PDKIM_ALGO_RSA_SHA1)
- sha1_update(&(sha1_headers),(unsigned char *)rh,strlen(rh));
- else
- sha2_update(&(sha2_headers),(unsigned char *)rh,strlen(rh));
- #ifdef PDKIM_DEBUG
- if (ctx->debug_stream)
- pdkim_quoteprint(ctx->debug_stream, rh, strlen(rh), 1);
- #endif
- free(rh);
- (hdrs->value)[0] = '_';
- break;
- }
- hdrs = hdrs->next;
- }
- if (q == NULL) break;
- p = q+1;
- }
- free(b);
- }
-
- #ifdef PDKIM_DEBUG
- if (ctx->debug_stream)
- fprintf(ctx->debug_stream,
- "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
- #endif
-
- /* SIGNING ---------------------------------------------------------------- */
- if (ctx->mode == PDKIM_MODE_SIGN) {
- /* Copy headernames to signature struct */
- sig->headernames = strdup(headernames->str);
- pdkim_strfree(headernames);
-
- /* Create signature header with b= omitted */
- sig_hdr = pdkim_create_header(ctx->sig,0);
- }
- /* VERIFICATION ----------------------------------------------------------- */
- else {
- sig_hdr = strdup(sig->rawsig_no_b_val);
- }
- /* ------------------------------------------------------------------------ */
-
- if (sig_hdr == NULL) 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 == NULL) return PDKIM_ERR_OOM;
- sig_hdr = relaxed_hdr;
- }
-
- #ifdef PDKIM_DEBUG
- if (ctx->debug_stream) {
- fprintf(ctx->debug_stream,
- "PDKIM >> Signed DKIM-Signature header, canonicalized >>>>>>>>>>>>>>>>>\n");
- pdkim_quoteprint(ctx->debug_stream, sig_hdr, strlen(sig_hdr), 1);
- fprintf(ctx->debug_stream,
- "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
- }
- #endif
-
- /* Finalize header hash */
- if (sig->algo == PDKIM_ALGO_RSA_SHA1) {
- sha1_update(&(sha1_headers),(unsigned char *)sig_hdr,strlen(sig_hdr));
- sha1_finish(&(sha1_headers),(unsigned char *)headerhash);
- #ifdef PDKIM_DEBUG
- if (ctx->debug_stream) {
- fprintf(ctx->debug_stream, "PDKIM [%s] hh computed: ", sig->domain);
- pdkim_hexprint(ctx->debug_stream, headerhash, 20, 1);
- }
- #endif
- }
- else {
- sha2_update(&(sha2_headers),(unsigned char *)sig_hdr,strlen(sig_hdr));
- sha2_finish(&(sha2_headers),(unsigned char *)headerhash);
- #ifdef PDKIM_DEBUG
- if (ctx->debug_stream) {
- fprintf(ctx->debug_stream, "PDKIM [%s] hh computed: ", sig->domain);
- pdkim_hexprint(ctx->debug_stream, headerhash, 32, 1);
- }
- #endif
- }
-
- free(sig_hdr);
-
- /* SIGNING ---------------------------------------------------------------- */
- if (ctx->mode == PDKIM_MODE_SIGN) {
- rsa_context rsa;
-
- rsa_init(&rsa,RSA_PKCS_V15,0,NULL,NULL);
-
- /* Perform private key operation */
- if (rsa_parse_key(&rsa, (unsigned char *)sig->rsa_privkey,
- strlen(sig->rsa_privkey), NULL, 0) != 0) {
- return PDKIM_ERR_RSA_PRIVKEY;
- }
-
- sig->sigdata_len = mpi_size(&(rsa.N));
- sig->sigdata = malloc(sig->sigdata_len);
- if (sig->sigdata == NULL) return PDKIM_ERR_OOM;
-
- if (rsa_pkcs1_sign( &rsa, RSA_PRIVATE,
- ((sig->algo == PDKIM_ALGO_RSA_SHA1)?
- RSA_SHA1:RSA_SHA256),
- 0,
- (unsigned char *)headerhash,
- (unsigned char *)sig->sigdata ) != 0) {
- return PDKIM_ERR_RSA_SIGNING;
- }
-
- rsa_free(&rsa);
-
- #ifdef PDKIM_DEBUG
- if (ctx->debug_stream) {
- fprintf(ctx->debug_stream, "PDKIM [%s] b computed: ",
- sig->domain);
- pdkim_hexprint(ctx->debug_stream, sig->sigdata, sig->sigdata_len, 1);
- }
- #endif
-
- sig->signature_header = pdkim_create_header(ctx->sig,1);
- if (sig->signature_header == NULL) return PDKIM_ERR_OOM;
- }
- /* VERIFICATION ----------------------------------------------------------- */
- else {
- rsa_context rsa;
- char *dns_txt_name, *dns_txt_reply;
-
- rsa_init(&rsa,RSA_PKCS_V15,0,NULL,NULL);
-
- dns_txt_name = malloc(PDKIM_DNS_TXT_MAX_NAMELEN);
- if (dns_txt_name == NULL) return PDKIM_ERR_OOM;
- dns_txt_reply = malloc(PDKIM_DNS_TXT_MAX_RECLEN);
- if (dns_txt_reply == NULL) {
- 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;
- }
-
- #ifdef PDKIM_DEBUG
- if (ctx->debug_stream) {
- fprintf(ctx->debug_stream,
- "PDKIM >> Parsing public key record >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
- fprintf(ctx->debug_stream,"Raw record: ");
- pdkim_quoteprint(ctx->debug_stream, dns_txt_reply, strlen(dns_txt_reply), 1);
- }
- #endif
-
- sig->pubkey = pdkim_parse_pubkey_record(ctx,dns_txt_reply);
- if (sig->pubkey == NULL) {
- sig->verify_status = PDKIM_VERIFY_INVALID;
- sig->verify_ext_status = PDKIM_VERIFY_INVALID_PUBKEY_PARSING;
- #ifdef PDKIM_DEBUG
- if (ctx->debug_stream) {
- fprintf(ctx->debug_stream,"Error while parsing public key record\n");
- fprintf(ctx->debug_stream,
- "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
- }
- #endif
- goto NEXT_VERIFY;
- }
-
- #ifdef PDKIM_DEBUG
- if (ctx->debug_stream) {
- fprintf(ctx->debug_stream,
- "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
- }
- #endif
-
- if (rsa_parse_public_key(&rsa,
- (unsigned char *)sig->pubkey->key,
- sig->pubkey->key_len) != 0) {
- sig->verify_status = PDKIM_VERIFY_INVALID;
- sig->verify_ext_status = PDKIM_VERIFY_INVALID_PUBKEY_PARSING;
- goto NEXT_VERIFY;
- }
-
- /* Check the signature */
- if (rsa_pkcs1_verify(&rsa,
- RSA_PUBLIC,
- ((sig->algo == PDKIM_ALGO_RSA_SHA1)?
- RSA_SHA1:RSA_SHA256),
- 0,
- (unsigned char *)headerhash,
- (unsigned char *)sig->sigdata) != 0) {
- sig->verify_status = PDKIM_VERIFY_FAIL;
- sig->verify_ext_status = PDKIM_VERIFY_FAIL_MESSAGE;
- #ifdef PDKIM_DEBUG
- if (ctx->debug_stream) {
- fprintf(ctx->debug_stream, "PDKIM [%s] signature did NOT verify OK\n",
- sig->domain);
- }
- #endif
- goto NEXT_VERIFY;
- }
-
- /* We have a winner! */
- sig->verify_status = PDKIM_VERIFY_PASS;
-
- #ifdef PDKIM_DEBUG
- if (ctx->debug_stream) {
- fprintf(ctx->debug_stream, "PDKIM [%s] signature verified OK\n",
- sig->domain);
- }
- #endif
-
- NEXT_VERIFY:
- rsa_free(&rsa);
- free(dns_txt_name);
- free(dns_txt_reply);
- }
-
- sig = sig->next;
- }
-
- /* If requested, set return pointer to signature(s) */
- if (return_signatures != NULL) {
- *return_signatures = ctx->sig;
- }
-
- return PDKIM_OK;
-}
-
-
-/* -------------------------------------------------------------------------- */
-DLLEXPORT pdkim_ctx *pdkim_init_verify(int input_mode,
- int(*dns_txt_callback)(char *, char *)
- ) {
- pdkim_ctx *ctx = malloc(sizeof(pdkim_ctx));
- if (ctx == NULL) return NULL;
- memset(ctx,0,sizeof(pdkim_ctx));
-
- ctx->linebuf = malloc(PDKIM_MAX_BODY_LINE_LEN);
- if (ctx->linebuf == NULL) {
- free(ctx);
- return NULL;
- }
-
- ctx->mode = PDKIM_MODE_VERIFY;
- ctx->input_mode = input_mode;
- ctx->dns_txt_callback = dns_txt_callback;
-
- return ctx;
-}
-
-
-/* -------------------------------------------------------------------------- */
-DLLEXPORT pdkim_ctx *pdkim_init_sign(int input_mode,
- char *domain,
- char *selector,
- char *rsa_privkey) {
- pdkim_ctx *ctx;
- pdkim_signature *sig;
-
- if (!domain || !selector || !rsa_privkey) return NULL;
-
- ctx = malloc(sizeof(pdkim_ctx));
- if (ctx == NULL) return NULL;
- memset(ctx,0,sizeof(pdkim_ctx));
-
- ctx->linebuf = malloc(PDKIM_MAX_BODY_LINE_LEN);
- if (ctx->linebuf == NULL) {
- free(ctx);
- return NULL;
- }
-
- sig = malloc(sizeof(pdkim_signature));
- if (sig == NULL) {
- free(ctx->linebuf);
- free(ctx);
- return NULL;
- }
- memset(sig,0,sizeof(pdkim_signature));
- sig->bodylength = -1;
-
- ctx->mode = PDKIM_MODE_SIGN;
- ctx->input_mode = input_mode;
- ctx->sig = sig;
-
- ctx->sig->domain = strdup(domain);
- ctx->sig->selector = strdup(selector);
- ctx->sig->rsa_privkey = strdup(rsa_privkey);
-
- if (!ctx->sig->domain || !ctx->sig->selector || !ctx->sig->rsa_privkey) {
- pdkim_free_ctx(ctx);
- return NULL;
- }
-
- ctx->sig->sha1_body = malloc(sizeof(sha1_context));
- if (ctx->sig->sha1_body == NULL) {
- pdkim_free_ctx(ctx);
- return NULL;
- }
- sha1_starts(ctx->sig->sha1_body);
-
- ctx->sig->sha2_body = malloc(sizeof(sha2_context));
- if (ctx->sig->sha2_body == NULL) {
- pdkim_free_ctx(ctx);
- return NULL;
- }
- sha2_starts(ctx->sig->sha2_body,0);
-
- return ctx;
-}
-
-#ifdef PDKIM_DEBUG
-/* -------------------------------------------------------------------------- */
-DLLEXPORT void pdkim_set_debug_stream(pdkim_ctx *ctx,
- FILE *debug_stream) {
- ctx->debug_stream = debug_stream;
-}
-#endif
-
-/* -------------------------------------------------------------------------- */
-DLLEXPORT int pdkim_set_optional(pdkim_ctx *ctx,
- char *sign_headers,
- char *identity,
- int canon_headers,
- int canon_body,
- long bodylength,
- int algo,
- unsigned long created,
- unsigned long expires) {
-
- if (identity != NULL) {
- ctx->sig->identity = strdup(identity);
- if (ctx->sig->identity == NULL) return PDKIM_ERR_OOM;
- }
-
- if (sign_headers != NULL) {
- ctx->sig->sign_headers = strdup(sign_headers);
- if (ctx->sig->sign_headers == NULL) return PDKIM_ERR_OOM;
- }
-
- ctx->sig->canon_headers = canon_headers;
- ctx->sig->canon_body = canon_body;
- ctx->sig->bodylength = bodylength;
- ctx->sig->algo = algo;
- ctx->sig->created = created;
- ctx->sig->expires = expires;
-
- return PDKIM_OK;
-}
git://git.exim.org / exim.git / blobdiff