You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
 

497 lines
14 KiB

diff --git a/lib/dns/dnssec.c b/lib/dns/dnssec.c
index 00a0080..336c4da 100644
--- a/lib/dns/dnssec.c
+++ b/lib/dns/dnssec.c
@@ -982,6 +982,8 @@ dns_dnssec_verifymessage(isc_buffer_t *source, dns_message_t *msg,
mctx = msg->mctx;
msg->verify_attempted = 1;
+ msg->verified_sig = 0;
+ msg->sig0status = dns_tsigerror_badsig;
if (is_response(msg)) {
if (msg->query.base == NULL)
@@ -1076,6 +1078,7 @@ dns_dnssec_verifymessage(isc_buffer_t *source, dns_message_t *msg,
}
msg->verified_sig = 1;
+ msg->sig0status = dns_rcode_noerror;
dst_context_destroy(&ctx);
dns_rdata_freestruct(&sig);
diff --git a/lib/dns/message.c b/lib/dns/message.c
index 1417067..0621175 100644
--- a/lib/dns/message.c
+++ b/lib/dns/message.c
@@ -3052,12 +3052,19 @@ dns_message_signer(dns_message_t *msg, dns_name_t *signer) {
result = dns_rdata_tostruct(&rdata, &tsig, NULL);
INSIST(result == ISC_R_SUCCESS);
- if (msg->tsigstatus != dns_rcode_noerror)
+ if (msg->verified_sig &&
+ msg->tsigstatus == dns_rcode_noerror &&
+ tsig.error == dns_rcode_noerror)
+ {
+ result = ISC_R_SUCCESS;
+ } else if ((!msg->verified_sig) ||
+ (msg->tsigstatus != dns_rcode_noerror))
+ {
result = DNS_R_TSIGVERIFYFAILURE;
- else if (tsig.error != dns_rcode_noerror)
+ } else {
+ INSIST(tsig.error != dns_rcode_noerror);
result = DNS_R_TSIGERRORSET;
- else
- result = ISC_R_SUCCESS;
+ }
dns_rdata_freestruct(&tsig);
if (msg->tsigkey == NULL) {
diff --git a/lib/dns/tsig.c b/lib/dns/tsig.c
index 3239bff..7b91d1e 100644
--- a/lib/dns/tsig.c
+++ b/lib/dns/tsig.c
@@ -941,11 +941,20 @@ dns_tsig_sign(dns_message_t *msg) {
isc_buffer_putuint48(&otherbuf, tsig.timesigned);
}
- if (key->key != NULL && tsig.error != dns_tsigerror_badsig) {
+ if ((key->key != NULL) &&
+ (tsig.error != dns_tsigerror_badsig) &&
+ (tsig.error != dns_tsigerror_badkey))
+ {
unsigned char header[DNS_MESSAGE_HEADERLEN];
isc_buffer_t headerbuf;
isc_uint16_t digestbits;
+ /*
+ * If it is a response, we assume that the request MAC
+ * has validated at this point. This is why we include a
+ * MAC length > 0 in the reply.
+ */
+
ret = dst_context_create3(key->key, mctx,
DNS_LOGCATEGORY_DNSSEC,
ISC_TRUE, &ctx);
@@ -953,7 +962,7 @@ dns_tsig_sign(dns_message_t *msg) {
return (ret);
/*
- * If this is a response, digest the query signature.
+ * If this is a response, digest the request's MAC.
*/
if (response) {
dns_rdata_t querytsigrdata = DNS_RDATA_INIT;
@@ -1083,6 +1092,17 @@ dns_tsig_sign(dns_message_t *msg) {
dst_context_destroy(&ctx);
digestbits = dst_key_getbits(key->key);
if (digestbits != 0) {
+ /*
+ * XXXRAY: Is this correct? What is the
+ * expected behavior when digestbits is not an
+ * integral multiple of 8? It looks like bytes
+ * should either be (digestbits/8) or
+ * (digestbits+7)/8.
+ *
+ * In any case, for current algorithms,
+ * digestbits are an integral multiple of 8, so
+ * it has the same effect as (digestbits/8).
+ */
unsigned int bytes = (digestbits + 1) / 8;
if (response && bytes < querytsig.siglen)
bytes = querytsig.siglen;
@@ -1196,6 +1216,8 @@ dns_tsig_verify(isc_buffer_t *source, dns_message_t *msg,
REQUIRE(tsigkey == NULL || VALID_TSIG_KEY(tsigkey));
msg->verify_attempted = 1;
+ msg->verified_sig = 0;
+ msg->tsigstatus = dns_tsigerror_badsig;
if (msg->tcp_continuation) {
if (tsigkey == NULL || msg->querytsig == NULL)
@@ -1294,19 +1316,6 @@ dns_tsig_verify(isc_buffer_t *source, dns_message_t *msg,
key = tsigkey->key;
/*
- * Is the time ok?
- */
- if (now + msg->timeadjust > tsig.timesigned + tsig.fudge) {
- msg->tsigstatus = dns_tsigerror_badtime;
- tsig_log(msg->tsigkey, 2, "signature has expired");
- return (DNS_R_CLOCKSKEW);
- } else if (now + msg->timeadjust < tsig.timesigned - tsig.fudge) {
- msg->tsigstatus = dns_tsigerror_badtime;
- tsig_log(msg->tsigkey, 2, "signature is in the future");
- return (DNS_R_CLOCKSKEW);
- }
-
- /*
* Check digest length.
*/
alg = dst_key_alg(key);
@@ -1315,31 +1324,19 @@ dns_tsig_verify(isc_buffer_t *source, dns_message_t *msg,
return (ret);
if (alg == DST_ALG_HMACMD5 || alg == DST_ALG_HMACSHA1 ||
alg == DST_ALG_HMACSHA224 || alg == DST_ALG_HMACSHA256 ||
- alg == DST_ALG_HMACSHA384 || alg == DST_ALG_HMACSHA512) {
- isc_uint16_t digestbits = dst_key_getbits(key);
+ alg == DST_ALG_HMACSHA384 || alg == DST_ALG_HMACSHA512)
+ {
if (tsig.siglen > siglen) {
- tsig_log(msg->tsigkey, 2, "signature length to big");
+ tsig_log(msg->tsigkey, 2, "signature length too big");
return (DNS_R_FORMERR);
}
if (tsig.siglen > 0 &&
- (tsig.siglen < 10 || tsig.siglen < ((siglen + 1) / 2))) {
+ (tsig.siglen < 10 || tsig.siglen < ((siglen + 1) / 2)))
+ {
tsig_log(msg->tsigkey, 2,
"signature length below minimum");
return (DNS_R_FORMERR);
}
- if (tsig.siglen > 0 && digestbits != 0 &&
- tsig.siglen < ((digestbits + 1) / 8)) {
- msg->tsigstatus = dns_tsigerror_badtrunc;
- tsig_log(msg->tsigkey, 2,
- "truncated signature length too small");
- return (DNS_R_TSIGVERIFYFAILURE);
- }
- if (tsig.siglen > 0 && digestbits == 0 &&
- tsig.siglen < siglen) {
- msg->tsigstatus = dns_tsigerror_badtrunc;
- tsig_log(msg->tsigkey, 2, "signature length too small");
- return (DNS_R_TSIGVERIFYFAILURE);
- }
}
if (tsig.siglen > 0) {
@@ -1451,34 +1448,92 @@ dns_tsig_verify(isc_buffer_t *source, dns_message_t *msg,
ret = dst_context_verify(ctx, &sig_r);
if (ret == DST_R_VERIFYFAILURE) {
- msg->tsigstatus = dns_tsigerror_badsig;
ret = DNS_R_TSIGVERIFYFAILURE;
tsig_log(msg->tsigkey, 2,
"signature failed to verify(1)");
goto cleanup_context;
- } else if (ret != ISC_R_SUCCESS)
+ } else if (ret != ISC_R_SUCCESS) {
goto cleanup_context;
-
- dst_context_destroy(&ctx);
+ }
} else if (tsig.error != dns_tsigerror_badsig &&
tsig.error != dns_tsigerror_badkey) {
- msg->tsigstatus = dns_tsigerror_badsig;
tsig_log(msg->tsigkey, 2, "signature was empty");
return (DNS_R_TSIGVERIFYFAILURE);
}
- msg->tsigstatus = dns_rcode_noerror;
+ /*
+ * Here at this point, the MAC has been verified. Even if any of
+ * the following code returns a TSIG error, the reply will be
+ * signed and WILL always include the request MAC in the digest
+ * computation.
+ */
+
+ /*
+ * Is the time ok?
+ */
+ if (now + msg->timeadjust > tsig.timesigned + tsig.fudge) {
+ msg->tsigstatus = dns_tsigerror_badtime;
+ tsig_log(msg->tsigkey, 2, "signature has expired");
+ ret = DNS_R_CLOCKSKEW;
+ goto cleanup_context;
+ } else if (now + msg->timeadjust < tsig.timesigned - tsig.fudge) {
+ msg->tsigstatus = dns_tsigerror_badtime;
+ tsig_log(msg->tsigkey, 2, "signature is in the future");
+ ret = DNS_R_CLOCKSKEW;
+ goto cleanup_context;
+ }
+
+ if (
+#ifndef PK11_MD5_DISABLE
+ alg == DST_ALG_HMACMD5 ||
+#endif
+ alg == DST_ALG_HMACSHA1 ||
+ alg == DST_ALG_HMACSHA224 || alg == DST_ALG_HMACSHA256 ||
+ alg == DST_ALG_HMACSHA384 || alg == DST_ALG_HMACSHA512)
+ {
+ isc_uint16_t digestbits = dst_key_getbits(key);
+
+ /*
+ * XXXRAY: Is this correct? What is the expected
+ * behavior when digestbits is not an integral multiple
+ * of 8? It looks like bytes should either be
+ * (digestbits/8) or (digestbits+7)/8.
+ *
+ * In any case, for current algorithms, digestbits are
+ * an integral multiple of 8, so it has the same effect
+ * as (digestbits/8).
+ */
+ if (tsig.siglen > 0 && digestbits != 0 &&
+ tsig.siglen < ((digestbits + 1) / 8))
+ {
+ msg->tsigstatus = dns_tsigerror_badtrunc;
+ tsig_log(msg->tsigkey, 2,
+ "truncated signature length too small");
+ ret = DNS_R_TSIGVERIFYFAILURE;
+ goto cleanup_context;
+ }
+ if (tsig.siglen > 0 && digestbits == 0 &&
+ tsig.siglen < siglen)
+ {
+ msg->tsigstatus = dns_tsigerror_badtrunc;
+ tsig_log(msg->tsigkey, 2, "signature length too small");
+ ret = DNS_R_TSIGVERIFYFAILURE;
+ goto cleanup_context;
+ }
+ }
if (tsig.error != dns_rcode_noerror) {
+ msg->tsigstatus = tsig.error;
if (tsig.error == dns_tsigerror_badtime)
- return (DNS_R_CLOCKSKEW);
+ ret = DNS_R_CLOCKSKEW;
else
- return (DNS_R_TSIGERRORSET);
+ ret = DNS_R_TSIGERRORSET;
+ goto cleanup_context;
}
+ msg->tsigstatus = dns_rcode_noerror;
msg->verified_sig = 1;
-
- return (ISC_R_SUCCESS);
+ ret = ISC_R_SUCCESS;
cleanup_context:
if (ctx != NULL)
@@ -1503,6 +1558,8 @@ tsig_verify_tcp(isc_buffer_t *source, dns_message_t *msg) {
isc_uint16_t addcount, id;
isc_boolean_t has_tsig = ISC_FALSE;
isc_mem_t *mctx;
+ unsigned int siglen;
+ unsigned int alg;
REQUIRE(source != NULL);
REQUIRE(msg != NULL);
@@ -1510,12 +1567,16 @@ tsig_verify_tcp(isc_buffer_t *source, dns_message_t *msg) {
REQUIRE(msg->tcp_continuation == 1);
REQUIRE(msg->querytsig != NULL);
+ msg->verified_sig = 0;
+ msg->tsigstatus = dns_tsigerror_badsig;
+
if (!is_response(msg))
return (DNS_R_EXPECTEDRESPONSE);
mctx = msg->mctx;
tsigkey = dns_message_gettsigkey(msg);
+ key = tsigkey->key;
/*
* Extract and parse the previous TSIG
@@ -1548,7 +1609,8 @@ tsig_verify_tcp(isc_buffer_t *source, dns_message_t *msg) {
* Do the key name and algorithm match that of the query?
*/
if (!dns_name_equal(keyname, &tsigkey->name) ||
- !dns_name_equal(&tsig.algorithm, &querytsig.algorithm)) {
+ !dns_name_equal(&tsig.algorithm, &querytsig.algorithm))
+ {
msg->tsigstatus = dns_tsigerror_badkey;
ret = DNS_R_TSIGVERIFYFAILURE;
tsig_log(msg->tsigkey, 2,
@@ -1557,27 +1619,40 @@ tsig_verify_tcp(isc_buffer_t *source, dns_message_t *msg) {
}
/*
- * Is the time ok?
+ * Check digest length.
*/
- isc_stdtime_get(&now);
-
- if (now + msg->timeadjust > tsig.timesigned + tsig.fudge) {
- msg->tsigstatus = dns_tsigerror_badtime;
- tsig_log(msg->tsigkey, 2, "signature has expired");
- ret = DNS_R_CLOCKSKEW;
- goto cleanup_querystruct;
- } else if (now + msg->timeadjust <
- tsig.timesigned - tsig.fudge) {
- msg->tsigstatus = dns_tsigerror_badtime;
- tsig_log(msg->tsigkey, 2,
- "signature is in the future");
- ret = DNS_R_CLOCKSKEW;
+ alg = dst_key_alg(key);
+ ret = dst_key_sigsize(key, &siglen);
+ if (ret != ISC_R_SUCCESS)
goto cleanup_querystruct;
+ if (
+#ifndef PK11_MD5_DISABLE
+ alg == DST_ALG_HMACMD5 ||
+#endif
+ alg == DST_ALG_HMACSHA1 ||
+ alg == DST_ALG_HMACSHA224 ||
+ alg == DST_ALG_HMACSHA256 ||
+ alg == DST_ALG_HMACSHA384 ||
+ alg == DST_ALG_HMACSHA512)
+ {
+ if (tsig.siglen > siglen) {
+ tsig_log(tsigkey, 2,
+ "signature length too big");
+ ret = DNS_R_FORMERR;
+ goto cleanup_querystruct;
+ }
+ if (tsig.siglen > 0 &&
+ (tsig.siglen < 10 ||
+ tsig.siglen < ((siglen + 1) / 2)))
+ {
+ tsig_log(tsigkey, 2,
+ "signature length below minimum");
+ ret = DNS_R_FORMERR;
+ goto cleanup_querystruct;
+ }
}
}
- key = tsigkey->key;
-
if (msg->tsigctx == NULL) {
ret = dst_context_create3(key, mctx,
DNS_LOGCATEGORY_DNSSEC,
@@ -1670,10 +1745,12 @@ tsig_verify_tcp(isc_buffer_t *source, dns_message_t *msg) {
sig_r.length = tsig.siglen;
if (tsig.siglen == 0) {
if (tsig.error != dns_rcode_noerror) {
- if (tsig.error == dns_tsigerror_badtime)
+ msg->tsigstatus = tsig.error;
+ if (tsig.error == dns_tsigerror_badtime) {
ret = DNS_R_CLOCKSKEW;
- else
+ } else {
ret = DNS_R_TSIGERRORSET;
+ }
} else {
tsig_log(msg->tsigkey, 2,
"signature is empty");
@@ -1684,29 +1761,111 @@ tsig_verify_tcp(isc_buffer_t *source, dns_message_t *msg) {
ret = dst_context_verify(msg->tsigctx, &sig_r);
if (ret == DST_R_VERIFYFAILURE) {
- msg->tsigstatus = dns_tsigerror_badsig;
tsig_log(msg->tsigkey, 2,
"signature failed to verify(2)");
ret = DNS_R_TSIGVERIFYFAILURE;
goto cleanup_context;
+ } else if (ret != ISC_R_SUCCESS) {
+ goto cleanup_context;
}
- else if (ret != ISC_R_SUCCESS)
+
+ /*
+ * Here at this point, the MAC has been verified. Even
+ * if any of the following code returns a TSIG error,
+ * the reply will be signed and WILL always include the
+ * request MAC in the digest computation.
+ */
+
+ /*
+ * Is the time ok?
+ */
+ isc_stdtime_get(&now);
+
+ if (now + msg->timeadjust > tsig.timesigned + tsig.fudge) {
+ msg->tsigstatus = dns_tsigerror_badtime;
+ tsig_log(msg->tsigkey, 2, "signature has expired");
+ ret = DNS_R_CLOCKSKEW;
+ goto cleanup_context;
+ } else if (now + msg->timeadjust <
+ tsig.timesigned - tsig.fudge)
+ {
+ msg->tsigstatus = dns_tsigerror_badtime;
+ tsig_log(msg->tsigkey, 2,
+ "signature is in the future");
+ ret = DNS_R_CLOCKSKEW;
goto cleanup_context;
+ }
- dst_context_destroy(&msg->tsigctx);
+ alg = dst_key_alg(key);
+ ret = dst_key_sigsize(key, &siglen);
+ if (ret != ISC_R_SUCCESS)
+ goto cleanup_context;
+ if (
+#ifndef PK11_MD5_DISABLE
+ alg == DST_ALG_HMACMD5 ||
+#endif
+ alg == DST_ALG_HMACSHA1 ||
+ alg == DST_ALG_HMACSHA224 ||
+ alg == DST_ALG_HMACSHA256 ||
+ alg == DST_ALG_HMACSHA384 ||
+ alg == DST_ALG_HMACSHA512)
+ {
+ isc_uint16_t digestbits = dst_key_getbits(key);
+
+ /*
+ * XXXRAY: Is this correct? What is the
+ * expected behavior when digestbits is not an
+ * integral multiple of 8? It looks like bytes
+ * should either be (digestbits/8) or
+ * (digestbits+7)/8.
+ *
+ * In any case, for current algorithms,
+ * digestbits are an integral multiple of 8, so
+ * it has the same effect as (digestbits/8).
+ */
+ if (tsig.siglen > 0 && digestbits != 0 &&
+ tsig.siglen < ((digestbits + 1) / 8))
+ {
+ msg->tsigstatus = dns_tsigerror_badtrunc;
+ tsig_log(msg->tsigkey, 2,
+ "truncated signature length "
+ "too small");
+ ret = DNS_R_TSIGVERIFYFAILURE;
+ goto cleanup_context;
+ }
+ if (tsig.siglen > 0 && digestbits == 0 &&
+ tsig.siglen < siglen)
+ {
+ msg->tsigstatus = dns_tsigerror_badtrunc;
+ tsig_log(msg->tsigkey, 2,
+ "signature length too small");
+ ret = DNS_R_TSIGVERIFYFAILURE;
+ goto cleanup_context;
+ }
+ }
+
+ if (tsig.error != dns_rcode_noerror) {
+ msg->tsigstatus = tsig.error;
+ if (tsig.error == dns_tsigerror_badtime)
+ ret = DNS_R_CLOCKSKEW;
+ else
+ ret = DNS_R_TSIGERRORSET;
+ goto cleanup_context;
+ }
}
msg->tsigstatus = dns_rcode_noerror;
- return (ISC_R_SUCCESS);
+ msg->verified_sig = 1;
+ ret = ISC_R_SUCCESS;
cleanup_context:
- dst_context_destroy(&msg->tsigctx);
+ if (msg->tsigctx != NULL)
+ dst_context_destroy(&msg->tsigctx);
cleanup_querystruct:
dns_rdata_freestruct(&querytsig);
return (ret);
-
}
isc_result_t