* Exim - an Internet mail transport agent *
*************************************************/
-/* Copyright (c) University of Cambridge, 1995 - 2015 */
+/* Copyright (c) University of Cambridge, 1995 - 2016 */
/* See the file NOTICE for conditions of use and distribution. */
/* Code for DKIM support. Other DKIM relevant code is in
#include "pdkim/pdkim.h"
+int dkim_verify_oldpool;
pdkim_ctx *dkim_verify_ctx = NULL;
pdkim_signature *dkim_signatures = NULL;
pdkim_signature *dkim_cur_sig = NULL;
lookup_dnssec_authenticated = NULL;
if (dns_lookup(&dnsa, US name, T_TXT, NULL) != DNS_SUCCEED)
- return PDKIM_FAIL;
+ return PDKIM_FAIL; /*XXX better error detail? logging? */
/* Search for TXT record */
rr_offset += len;
answer_offset += len;
if (answer_offset >= PDKIM_DNS_TXT_MAX_RECLEN)
- return PDKIM_FAIL;
+ return PDKIM_FAIL; /*XXX better error detail? logging? */
}
return PDKIM_OK;
}
-return PDKIM_FAIL;
+return PDKIM_FAIL; /*XXX better error detail? logging? */
}
}
+
void
-dkim_exim_verify_init(void)
+dkim_exim_verify_init(BOOL dot_stuffing)
{
+/* 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. */
+
+dkim_verify_oldpool = store_pool;
+store_pool = POOL_PERM;
+
/* Free previous context if there is one */
if (dkim_verify_ctx)
/* Create new context */
-dkim_verify_ctx = pdkim_init_verify(&dkim_exim_query_dns_txt);
+dkim_verify_ctx = pdkim_init_verify(&dkim_exim_query_dns_txt, dot_stuffing);
dkim_collect_input = !!dkim_verify_ctx;
+
+/* Start feed up with any cached data */
+receive_get_cache();
+
+store_pool = dkim_verify_oldpool;
}
void
dkim_exim_verify_feed(uschar * data, int len)
{
+int rc;
+
+store_pool = POOL_PERM;
if ( dkim_collect_input
- && pdkim_feed(dkim_verify_ctx, (char *)data, len) != PDKIM_OK)
+ && (rc = pdkim_feed(dkim_verify_ctx, CS data, len)) != PDKIM_OK)
+ {
+ log_write(0, LOG_MAIN,
+ "DKIM: validation error: %.100s", pdkim_errstr(rc));
dkim_collect_input = FALSE;
+ }
+store_pool = dkim_verify_oldpool;
}
int dkim_signers_size = 0;
int dkim_signers_ptr = 0;
dkim_signers = NULL;
+int rc;
+
+store_pool = POOL_PERM;
/* Delete eventual previous signature chain */
"DKIM: Error while running this message through validation,"
" disabling signature verification.");
dkim_disable_verify = TRUE;
- return;
+ goto out;
}
dkim_collect_input = FALSE;
/* Finish DKIM operation and fetch link to signatures chain */
-if (pdkim_feed_finish(dkim_verify_ctx, &dkim_signatures) != PDKIM_OK)
- return;
+if ((rc = pdkim_feed_finish(dkim_verify_ctx, &dkim_signatures)) != PDKIM_OK)
+ {
+ log_write(0, LOG_MAIN,
+ "DKIM: validation error: %.100s", pdkim_errstr(rc));
+ goto out;
+ }
for (sig = dkim_signatures; sig; sig = sig->next)
{
string_sprintf("d=%s s=%s c=%s/%s a=%s b=%d ",
sig->domain,
sig->selector,
- sig->canon_headers == PDKIM_CANON_SIMPLE ? "simple" : "relaxed",
- sig->canon_body == PDKIM_CANON_SIMPLE ? "simple" : "relaxed",
- sig->algo == PDKIM_ALGO_RSA_SHA256 ? "rsa-sha256" : "rsa-sha1",
- sig->sigdata.len * 8
+ sig->canon_headers == PDKIM_CANON_SIMPLE ? "simple" : "relaxed",
+ sig->canon_body == PDKIM_CANON_SIMPLE ? "simple" : "relaxed",
+ sig->algo == PDKIM_ALGO_RSA_SHA256
+ ? "rsa-sha256"
+ : sig->algo == PDKIM_ALGO_RSA_SHA1 ? "rsa-sha1" : "err",
+ (int)sig->sigdata.len > -1 ? sig->sigdata.len * 8 : 0
),
sig->identity ? string_sprintf("i=%s ", sig->identity) : US"",
"syntax error in public key record]");
break;
+ case PDKIM_VERIFY_INVALID_SIGNATURE_ERROR:
+ logmsg = string_append(logmsg, &size, &ptr, 1,
+ "signature tag missing or invalid]");
+ break;
+
+ case PDKIM_VERIFY_INVALID_DKIM_VERSION:
+ logmsg = string_append(logmsg, &size, &ptr, 1,
+ "unsupported DKIM version]");
+ break;
+
default:
logmsg = string_append(logmsg, &size, &ptr, 1,
"unspecified problem]");
if (Ustrlen(dkim_signers) > 0)
dkim_signers[Ustrlen(dkim_signers) - 1] = '\0';
}
+
+out:
+store_pool = dkim_verify_oldpool;
}
uschar *
-dkim_exim_sign(int dkim_fd, uschar * dkim_private_key,
- const uschar * dkim_domain, uschar * dkim_selector,
- uschar * dkim_canon, uschar * dkim_sign_headers)
+dkim_exim_sign(int dkim_fd, struct ob_dkim * dkim)
{
+const uschar * dkim_domain;
int sep = 0;
uschar *seen_items = NULL;
int seen_items_size = 0;
store_pool = POOL_MAIN;
-if (!(dkim_domain = expand_cstring(dkim_domain)))
+if (!(dkim_domain = expand_cstring(dkim->dkim_domain)))
{
/* expansion error, do not send message. */
log_write(0, LOG_MAIN | LOG_PANIC, "failed to expand "
"dkim_domain: %s", expand_string_message);
- rc = NULL;
- goto CLEANUP;
+ goto bad;
}
/* Set $dkim_domain expansion variable to each unique domain in list. */
/* Set up $dkim_selector expansion variable. */
- if (!(dkim_signing_selector = expand_string(dkim_selector)))
+ if (!(dkim_signing_selector = expand_string(dkim->dkim_selector)))
{
log_write(0, LOG_MAIN | LOG_PANIC, "failed to expand "
"dkim_selector: %s", expand_string_message);
- rc = NULL;
- goto CLEANUP;
+ goto bad;
}
/* Get canonicalization to use */
- dkim_canon_expanded = dkim_canon ? expand_string(dkim_canon) : US"relaxed";
+ dkim_canon_expanded = dkim->dkim_canon
+ ? expand_string(dkim->dkim_canon) : US"relaxed";
if (!dkim_canon_expanded)
{
/* expansion error, do not send message. */
log_write(0, LOG_MAIN | LOG_PANIC, "failed to expand "
"dkim_canon: %s", expand_string_message);
- rc = NULL;
- goto CLEANUP;
+ goto bad;
}
if (Ustrcmp(dkim_canon_expanded, "relaxed") == 0)
}
dkim_sign_headers_expanded = NULL;
- if (dkim_sign_headers)
- if (!(dkim_sign_headers_expanded = expand_string(dkim_sign_headers)))
+ if (dkim->dkim_sign_headers)
+ if (!(dkim_sign_headers_expanded = expand_string(dkim->dkim_sign_headers)))
{
log_write(0, LOG_MAIN | LOG_PANIC, "failed to expand "
"dkim_sign_headers: %s", expand_string_message);
- rc = NULL;
- goto CLEANUP;
+ goto bad;
}
/* else pass NULL, which means default header list */
/* Get private key to use. */
- if (!(dkim_private_key_expanded = expand_string(dkim_private_key)))
+ if (!(dkim_private_key_expanded = expand_string(dkim->dkim_private_key)))
{
log_write(0, LOG_MAIN | LOG_PANIC, "failed to expand "
"dkim_private_key: %s", expand_string_message);
- rc = NULL;
- goto CLEANUP;
+ goto bad;
}
if ( Ustrlen(dkim_private_key_expanded) == 0
/* Looks like a filename, load the private key. */
memset(big_buffer, 0, big_buffer_size);
- privkey_fd = open(CS dkim_private_key_expanded, O_RDONLY);
- if (privkey_fd < 0)
+
+ if ((privkey_fd = open(CS dkim_private_key_expanded, O_RDONLY)) < 0)
{
log_write(0, LOG_MAIN | LOG_PANIC, "unable to open "
"private key file for reading: %s",
dkim_private_key_expanded);
- rc = NULL;
- goto CLEANUP;
+ goto bad;
}
if (read(privkey_fd, big_buffer, big_buffer_size - 2) < 0)
{
log_write(0, LOG_MAIN|LOG_PANIC, "unable to read private key file: %s",
dkim_private_key_expanded);
- rc = NULL;
- goto CLEANUP;
+ goto bad;
}
(void) close(privkey_fd);
dkim_private_key_expanded = big_buffer;
}
- ctx = pdkim_init_sign( (char *) dkim_signing_domain,
- (char *) dkim_signing_selector,
- (char *) dkim_private_key_expanded,
- PDKIM_ALGO_RSA_SHA256);
+ ctx = pdkim_init_sign( CS dkim_signing_domain,
+ CS dkim_signing_selector,
+ CS dkim_private_key_expanded,
+ PDKIM_ALGO_RSA_SHA256,
+ dkim->dot_stuffed);
pdkim_set_optional(ctx,
- (char *) dkim_sign_headers_expanded,
+ CS dkim_sign_headers_expanded,
NULL,
pdkim_canon,
pdkim_canon, -1, 0, 0);
lseek(dkim_fd, 0, SEEK_SET);
- while ((sread = read(dkim_fd, &buf, 4096)) > 0)
- if (pdkim_feed(ctx, buf, sread) != PDKIM_OK)
- {
- rc = NULL;
- goto CLEANUP;
- }
+ while ((sread = read(dkim_fd, &buf, sizeof(buf))) > 0)
+ if ((pdkim_rc = pdkim_feed(ctx, buf, sread)) != PDKIM_OK)
+ goto pk_bad;
/* Handle failed read above. */
if (sread == -1)
{
debug_printf("DKIM: Error reading -K file.\n");
save_errno = errno;
- rc = NULL;
- goto CLEANUP;
+ goto bad;
}
if ((pdkim_rc = pdkim_feed_finish(ctx, &signature)) != PDKIM_OK)
- {
- log_write(0, LOG_MAIN|LOG_PANIC, "DKIM: signing failed (RC %d)", pdkim_rc);
- rc = NULL;
- goto CLEANUP;
- }
+ goto pk_bad;
sigbuf = string_append(sigbuf, &sigsize, &sigptr, 2,
US signature->signature_header, US"\r\n");
rc = US"";
CLEANUP:
-if (ctx)
- pdkim_free_ctx(ctx);
-store_pool = old_pool;
-errno = save_errno;
-return rc;
+ if (ctx)
+ pdkim_free_ctx(ctx);
+ store_pool = old_pool;
+ errno = save_errno;
+ return rc;
+
+pk_bad:
+ log_write(0, LOG_MAIN|LOG_PANIC,
+ "DKIM: signing failed: %.100s", pdkim_errstr(pdkim_rc));
+bad:
+ rc = NULL;
+ goto CLEANUP;
}
#endif