-/* $Cambridge: exim/src/src/pdkim/pdkim.c,v 1.1.2.5 2009/02/27 17:04:20 tom Exp $ */
+/* $Cambridge: exim/src/src/pdkim/pdkim.c,v 1.1.2.6 2009/03/17 12:57:37 tom Exp $ */
/* pdkim.c */
#include <stdlib.h>
"relaxed",
NULL
};
+char *pdkim_hashes[] = {
+ "sha256",
+ "sha1",
+ NULL
+};
+char *pdkim_keytypes[] = {
+ "rsa",
+ NULL
+};
typedef struct pdkim_combined_canon_entry {
char *str;
}
break;
case 's':
- sig->selector = malloc(strlen(cur_val->str)+1);
- if (sig->selector == NULL) break;
- strcpy(sig->selector, cur_val->str);
+ sig->selector = strdup(cur_val->str);
break;
case 'd':
- sig->domain = malloc(strlen(cur_val->str)+1);
- if (sig->domain == NULL) break;
- strcpy(sig->domain, cur_val->str);
+ sig->domain = strdup(cur_val->str);
break;
case 'i':
sig->identity = pdkim_decode_qp(cur_val->str);
sig->bodylength = strtoul(cur_val->str,NULL,10);
break;
case 'h':
- sig->headernames = malloc(strlen(cur_val->str)+1);
- if (sig->headernames == NULL) break;
- strcpy(sig->headernames, cur_val->str);
+ sig->headernames = strdup(cur_val->str);
break;
case 'z':
sig->copiedheaders = pdkim_decode_qp(cur_val->str);
if (!(sig->domain && (*(sig->domain) != '\0') &&
sig->selector && (*(sig->selector) != '\0') &&
sig->headernames && (*(sig->headernames) != '\0') &&
- sig->bodyhash && (*(sig->bodyhash) != '\0') &&
- sig->sigdata && (*(sig->sigdata) != '\0') &&
+ sig->bodyhash &&
+ sig->sigdata &&
sig->version)) {
pdkim_free_sig(sig);
return NULL;
}
+/* -------------------------------------------------------------------------- */
+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 (*p != '\0') {
+
+ /* 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 == ';') {
+ 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:
+ 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) {
ctx->cur_header->len--;
}
+ ctx->num_headers++;
+ if (ctx->num_headers > PDKIM_MAX_HEADERS) goto BAIL;
+
/* Traverse all signatures */
while (sig != NULL) {
}
}
+ BAIL:
pdkim_strclear(ctx->cur_header); /* Re-use existing pdkim_str */
return PDKIM_OK;
};
ctx->cur_header = pdkim_strnew(NULL);
if (ctx->cur_header == NULL) return PDKIM_ERR_OOM;
}
- if (pdkim_strncat(ctx->cur_header,&data[p],1) == 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;
if (sig->canon_body == 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 */
+ rh = strdup(p->value); /* just copy it for simple canon */
if (rh == NULL) return PDKIM_ERR_OOM;
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) {
}
/* 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;
/* -------------------------------------------------------------------------- */
-pdkim_ctx *pdkim_init_verify(void) {
+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->mode = PDKIM_MODE_VERIFY;
+ ctx->input_mode = input_mode;
+ ctx->dns_txt_callback = dns_txt_callback;
+
return ctx;
}
/* -------------------------------------------------------------------------- */
-pdkim_ctx *pdkim_init_sign(char *domain,
+pdkim_ctx *pdkim_init_sign(int input_mode,
+ char *domain,
char *selector,
char *rsa_privkey) {
pdkim_ctx *ctx;
memset(sig,0,sizeof(pdkim_signature));
ctx->mode = PDKIM_MODE_SIGN;
+ ctx->input_mode = input_mode;
ctx->sig = sig;
ctx->sig->domain = malloc(strlen(domain)+1);
/* -------------------------------------------------------------------------- */
int pdkim_set_optional(pdkim_ctx *ctx,
- int input_mode,
char *sign_headers,
char *identity,
int canon_headers,
strcpy(ctx->sig->sign_headers, sign_headers);
}
- ctx->input_mode = input_mode;
ctx->sig->canon_headers = canon_headers;
ctx->sig->canon_body = canon_body;
ctx->sig->bodylength = bodylength;
};
+/* -------------------------------------------------------------------------- */
+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);
+ }
+}
/* -------------------------------------------------------------------------- */
if (sig->rsa_privkey != NULL) free(sig->rsa_privkey);
if (sig->sign_headers != NULL) free(sig->sign_headers);
+ if (sig->pubkey != NULL) pdkim_free_pubkey(sig->pubkey);
+
free(sig);
if (next != NULL) pdkim_free_sig(next);
}
git://git.exim.org / users / jgh / exim.git / blobdiff