static void
use(dst_key_t *key, isc_mem_t *mctx) {
isc_result_t ret;
const char *data = "This is some data";
unsigned char sig[512];
isc_buffer_t databuf, sigbuf;
isc_region_t datareg, sigreg;
dst_context_t *ctx = NULL;
isc_buffer_init(&sigbuf, sig, sizeof(sig));
/*
* Advance 1 byte for fun.
*/
isc_buffer_add(&sigbuf, 1);
isc_buffer_init(&databuf, data, strlen(data));
isc_buffer_add(&databuf, strlen(data));
isc_buffer_usedregion(&databuf, &datareg);
ret = dst_context_create(key, mctx, &ctx);
if (ret != ISC_R_SUCCESS) {
printf("contextcreate(%d) returned: %s\n", dst_key_alg(key),
isc_result_totext(ret));
return;
}
ret = dst_context_adddata(ctx, &datareg);
if (ret != ISC_R_SUCCESS) {
printf("adddata(%d) returned: %s\n", dst_key_alg(key),
isc_result_totext(ret));
dst_context_destroy(&ctx);
return;
}
ret = dst_context_sign(ctx, &sigbuf);
printf("sign(%d) returned: %s\n", dst_key_alg(key),
isc_result_totext(ret));
dst_context_destroy(&ctx);
isc_buffer_forward(&sigbuf, 1);
isc_buffer_remainingregion(&sigbuf, &sigreg);
ret = dst_context_create(key, mctx, &ctx);
if (ret != ISC_R_SUCCESS) {
printf("contextcreate(%d) returned: %s\n", dst_key_alg(key),
isc_result_totext(ret));
return;
}
ret = dst_context_adddata(ctx, &datareg);
if (ret != ISC_R_SUCCESS) {
printf("adddata(%d) returned: %s\n", dst_key_alg(key),
isc_result_totext(ret));
dst_context_destroy(&ctx);
return;
}
ret = dst_context_verify(ctx, &sigreg);
printf("verify(%d) returned: %s\n", dst_key_alg(key),
isc_result_totext(ret));
dst_context_destroy(&ctx);
}
static isc_result_t
tsig_verify_tcp(isc_buffer_t *source, dns_message_t *msg) {
dns_rdata_any_tsig_t tsig, querytsig;
isc_region_t r, source_r, header_r, sig_r;
isc_buffer_t databuf;
unsigned char data[32];
dns_name_t *keyname;
dns_rdata_t rdata = DNS_RDATA_INIT;
isc_stdtime_t now;
isc_result_t ret;
dns_tsigkey_t *tsigkey;
dst_key_t *key = NULL;
unsigned char header[DNS_MESSAGE_HEADERLEN];
isc_uint16_t addcount, id;
isc_boolean_t has_tsig = ISC_FALSE;
isc_mem_t *mctx;
REQUIRE(source != NULL);
REQUIRE(msg != NULL);
REQUIRE(dns_message_gettsigkey(msg) != NULL);
REQUIRE(msg->tcp_continuation == 1);
REQUIRE(msg->querytsig != NULL);
if (!is_response(msg))
return (DNS_R_EXPECTEDRESPONSE);
mctx = msg->mctx;
tsigkey = dns_message_gettsigkey(msg);
/*
* Extract and parse the previous TSIG
*/
ret = dns_rdataset_first(msg->querytsig);
if (ret != ISC_R_SUCCESS)
return (ret);
dns_rdataset_current(msg->querytsig, &rdata);
ret = dns_rdata_tostruct(&rdata, &querytsig, NULL);
if (ret != ISC_R_SUCCESS)
return (ret);
dns_rdata_reset(&rdata);
/*
* If there is a TSIG in this message, do some checks.
*/
if (msg->tsig != NULL) {
has_tsig = ISC_TRUE;
keyname = msg->tsigname;
ret = dns_rdataset_first(msg->tsig);
if (ret != ISC_R_SUCCESS)
goto cleanup_querystruct;
dns_rdataset_current(msg->tsig, &rdata);
ret = dns_rdata_tostruct(&rdata, &tsig, NULL);
if (ret != ISC_R_SUCCESS)
goto cleanup_querystruct;
/*
* 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))
{
msg->tsigstatus = dns_tsigerror_badkey;
ret = DNS_R_TSIGVERIFYFAILURE;
tsig_log(msg->tsigkey, 2,
"key name and algorithm do not match");
goto cleanup_querystruct;
}
/*
* 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_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;
goto cleanup_querystruct;
}
}
key = tsigkey->key;
if (msg->tsigctx == NULL) {
ret = dst_context_create(key, mctx, &msg->tsigctx);
if (ret != ISC_R_SUCCESS)
goto cleanup_querystruct;
/*
* Digest the length of the query signature
*/
isc_buffer_init(&databuf, data, sizeof(data));
isc_buffer_putuint16(&databuf, querytsig.siglen);
isc_buffer_usedregion(&databuf, &r);
ret = dst_context_adddata(msg->tsigctx, &r);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
/*
* Digest the data of the query signature
*/
if (querytsig.siglen > 0) {
r.length = querytsig.siglen;
r.base = querytsig.signature;
ret = dst_context_adddata(msg->tsigctx, &r);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
}
}
/*
* Extract the header.
*/
isc_buffer_usedregion(source, &r);
memcpy(header, r.base, DNS_MESSAGE_HEADERLEN);
isc_region_consume(&r, DNS_MESSAGE_HEADERLEN);
/*
* Decrement the additional field counter if necessary.
*/
if (has_tsig) {
memcpy(&addcount, &header[DNS_MESSAGE_HEADERLEN - 2], 2);
addcount = htons((isc_uint16_t)(ntohs(addcount) - 1));
memcpy(&header[DNS_MESSAGE_HEADERLEN - 2], &addcount, 2);
}
/*
* Put in the original id.
*/
/* XXX Can TCP transfers be forwarded? How would that work? */
if (has_tsig) {
id = htons(tsig.originalid);
memcpy(&header[0], &id, 2);
}
/*
* Digest the modified header.
*/
header_r.base = (unsigned char *) header;
header_r.length = DNS_MESSAGE_HEADERLEN;
ret = dst_context_adddata(msg->tsigctx, &header_r);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
/*
* Digest all non-TSIG records.
*/
isc_buffer_usedregion(source, &source_r);
r.base = source_r.base + DNS_MESSAGE_HEADERLEN;
if (has_tsig)
r.length = msg->sigstart - DNS_MESSAGE_HEADERLEN;
else
r.length = source_r.length - DNS_MESSAGE_HEADERLEN;
ret = dst_context_adddata(msg->tsigctx, &r);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
/*
* Digest the time signed and fudge.
*/
if (has_tsig) {
isc_buffer_init(&databuf, data, sizeof(data));
buffer_putuint48(&databuf, tsig.timesigned);
isc_buffer_putuint16(&databuf, tsig.fudge);
isc_buffer_usedregion(&databuf, &r);
ret = dst_context_adddata(msg->tsigctx, &r);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
sig_r.base = tsig.signature;
sig_r.length = tsig.siglen;
if (tsig.siglen == 0) {
if (tsig.error != dns_rcode_noerror) {
if (tsig.error == dns_tsigerror_badtime)
ret = DNS_R_CLOCKSKEW;
else
ret = DNS_R_TSIGERRORSET;
} else {
tsig_log(msg->tsigkey, 2,
"signature is empty");
ret = DNS_R_TSIGVERIFYFAILURE;
}
goto cleanup_context;
}
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");
ret = DNS_R_TSIGVERIFYFAILURE;
goto cleanup_context;
}
else if (ret != ISC_R_SUCCESS)
goto cleanup_context;
dst_context_destroy(&msg->tsigctx);
}
msg->tsigstatus = dns_rcode_noerror;
return (ISC_R_SUCCESS);
cleanup_context:
dst_context_destroy(&msg->tsigctx);
cleanup_querystruct:
dns_rdata_freestruct(&querytsig);
return (ret);
}
isc_result_t
dns_tsig_verify(isc_buffer_t *source, dns_message_t *msg,
dns_tsig_keyring_t *ring1, dns_tsig_keyring_t *ring2)
{
dns_rdata_any_tsig_t tsig, querytsig;
isc_region_t r, source_r, header_r, sig_r;
isc_buffer_t databuf;
unsigned char data[32];
dns_name_t *keyname;
dns_rdata_t rdata = DNS_RDATA_INIT;
isc_stdtime_t now;
isc_result_t ret;
dns_tsigkey_t *tsigkey;
dst_key_t *key = NULL;
unsigned char header[DNS_MESSAGE_HEADERLEN];
dst_context_t *ctx = NULL;
isc_mem_t *mctx;
isc_uint16_t addcount, id;
REQUIRE(source != NULL);
REQUIRE(DNS_MESSAGE_VALID(msg));
tsigkey = dns_message_gettsigkey(msg);
REQUIRE(tsigkey == NULL || VALID_TSIG_KEY(tsigkey));
msg->verify_attempted = 1;
if (msg->tcp_continuation)
return (tsig_verify_tcp(source, msg));
/*
* There should be a TSIG record...
*/
if (msg->tsig == NULL)
return (DNS_R_EXPECTEDTSIG);
/*
* If this is a response and there's no key or query TSIG, there
* shouldn't be one on the response.
*/
if (is_response(msg) &&
(tsigkey == NULL || msg->querytsig == NULL))
return (DNS_R_UNEXPECTEDTSIG);
mctx = msg->mctx;
/*
* If we're here, we know the message is well formed and contains a
* TSIG record.
*/
keyname = msg->tsigname;
ret = dns_rdataset_first(msg->tsig);
if (ret != ISC_R_SUCCESS)
return (ret);
dns_rdataset_current(msg->tsig, &rdata);
ret = dns_rdata_tostruct(&rdata, &tsig, NULL);
if (ret != ISC_R_SUCCESS)
return (ret);
dns_rdata_reset(&rdata);
if (is_response(msg)) {
ret = dns_rdataset_first(msg->querytsig);
if (ret != ISC_R_SUCCESS)
return (ret);
dns_rdataset_current(msg->querytsig, &rdata);
ret = dns_rdata_tostruct(&rdata, &querytsig, NULL);
if (ret != ISC_R_SUCCESS)
return (ret);
}
/*
* Do the key name and algorithm match that of the query?
*/
if (is_response(msg) &&
(!dns_name_equal(keyname, &tsigkey->name) ||
!dns_name_equal(&tsig.algorithm, &querytsig.algorithm)))
{
msg->tsigstatus = dns_tsigerror_badkey;
tsig_log(msg->tsigkey, 2,
"key name and algorithm do not match");
return (DNS_R_TSIGVERIFYFAILURE);
}
/*
* Get the current time.
*/
isc_stdtime_get(&now);
/*
* Find dns_tsigkey_t based on keyname.
*/
if (tsigkey == NULL) {
ret = ISC_R_NOTFOUND;
if (ring1 != NULL)
ret = dns_tsigkey_find(&tsigkey, keyname,
&tsig.algorithm, ring1);
if (ret == ISC_R_NOTFOUND && ring2 != NULL)
ret = dns_tsigkey_find(&tsigkey, keyname,
&tsig.algorithm, ring2);
if (ret != ISC_R_SUCCESS) {
msg->tsigstatus = dns_tsigerror_badkey;
ret = dns_tsigkey_create(keyname, &tsig.algorithm,
NULL, 0, ISC_FALSE, NULL,
now, now,
mctx, NULL, &msg->tsigkey);
if (ret != ISC_R_SUCCESS)
return (ret);
tsig_log(msg->tsigkey, 2, "unknown key");
return (DNS_R_TSIGVERIFYFAILURE);
}
msg->tsigkey = tsigkey;
}
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);
}
if (tsig.siglen > 0) {
sig_r.base = tsig.signature;
sig_r.length = tsig.siglen;
ret = dst_context_create(key, mctx, &ctx);
if (ret != ISC_R_SUCCESS)
return (ret);
if (is_response(msg)) {
isc_buffer_init(&databuf, data, sizeof(data));
isc_buffer_putuint16(&databuf, querytsig.siglen);
isc_buffer_usedregion(&databuf, &r);
ret = dst_context_adddata(ctx, &r);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
if (querytsig.siglen > 0) {
r.length = querytsig.siglen;
r.base = querytsig.signature;
ret = dst_context_adddata(ctx, &r);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
}
}
/*
* Extract the header.
*/
isc_buffer_usedregion(source, &r);
memcpy(header, r.base, DNS_MESSAGE_HEADERLEN);
isc_region_consume(&r, DNS_MESSAGE_HEADERLEN);
/*
* Decrement the additional field counter.
*/
memcpy(&addcount, &header[DNS_MESSAGE_HEADERLEN - 2], 2);
addcount = htons((isc_uint16_t)(ntohs(addcount) - 1));
memcpy(&header[DNS_MESSAGE_HEADERLEN - 2], &addcount, 2);
/*
* Put in the original id.
*/
id = htons(tsig.originalid);
memcpy(&header[0], &id, 2);
/*
* Digest the modified header.
*/
header_r.base = (unsigned char *) header;
header_r.length = DNS_MESSAGE_HEADERLEN;
ret = dst_context_adddata(ctx, &header_r);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
/*
* Digest all non-TSIG records.
*/
isc_buffer_usedregion(source, &source_r);
r.base = source_r.base + DNS_MESSAGE_HEADERLEN;
r.length = msg->sigstart - DNS_MESSAGE_HEADERLEN;
ret = dst_context_adddata(ctx, &r);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
/*
* Digest the key name.
*/
dns_name_toregion(&tsigkey->name, &r);
ret = dst_context_adddata(ctx, &r);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
isc_buffer_init(&databuf, data, sizeof(data));
isc_buffer_putuint16(&databuf, tsig.common.rdclass);
isc_buffer_putuint32(&databuf, msg->tsig->ttl);
isc_buffer_usedregion(&databuf, &r);
ret = dst_context_adddata(ctx, &r);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
/*
* Digest the key algorithm.
*/
dns_name_toregion(tsigkey->algorithm, &r);
ret = dst_context_adddata(ctx, &r);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
isc_buffer_clear(&databuf);
buffer_putuint48(&databuf, tsig.timesigned);
isc_buffer_putuint16(&databuf, tsig.fudge);
isc_buffer_putuint16(&databuf, tsig.error);
isc_buffer_putuint16(&databuf, tsig.otherlen);
isc_buffer_usedregion(&databuf, &r);
ret = dst_context_adddata(ctx, &r);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
if (tsig.otherlen > 0) {
r.base = tsig.other;
r.length = tsig.otherlen;
ret = dst_context_adddata(ctx, &r);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
}
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");
goto cleanup_context;
} 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;
if (tsig.error != dns_rcode_noerror) {
if (tsig.error == dns_tsigerror_badtime)
return (DNS_R_CLOCKSKEW);
else
return (DNS_R_TSIGERRORSET);
}
msg->verified_sig = 1;
return (ISC_R_SUCCESS);
cleanup_context:
if (ctx != NULL)
dst_context_destroy(&ctx);
return (ret);
}
isc_result_t
dns_tsig_sign(dns_message_t *msg) {
dns_tsigkey_t *key;
dns_rdata_any_tsig_t tsig, querytsig;
unsigned char data[128];
isc_buffer_t databuf, sigbuf;
isc_buffer_t *dynbuf;
dns_name_t *owner;
dns_rdata_t *rdata;
dns_rdatalist_t *datalist;
dns_rdataset_t *dataset;
isc_region_t r;
isc_stdtime_t now;
isc_mem_t *mctx;
dst_context_t *ctx = NULL;
isc_result_t ret;
unsigned char badtimedata[BADTIMELEN];
unsigned int sigsize = 0;
REQUIRE(msg != NULL);
REQUIRE(VALID_TSIG_KEY(dns_message_gettsigkey(msg)));
/*
* If this is a response, there should be a query tsig.
*/
if (is_response(msg) && msg->querytsig == NULL)
return (DNS_R_EXPECTEDTSIG);
dynbuf = NULL;
mctx = msg->mctx;
key = dns_message_gettsigkey(msg);
tsig.mctx = mctx;
tsig.common.rdclass = dns_rdataclass_any;
tsig.common.rdtype = dns_rdatatype_tsig;
ISC_LINK_INIT(&tsig.common, link);
dns_name_init(&tsig.algorithm, NULL);
dns_name_clone(key->algorithm, &tsig.algorithm);
isc_stdtime_get(&now);
tsig.timesigned = now + msg->timeadjust;
tsig.fudge = DNS_TSIG_FUDGE;
tsig.originalid = msg->id;
isc_buffer_init(&databuf, data, sizeof(data));
if (is_response(msg))
tsig.error = msg->querytsigstatus;
else
tsig.error = dns_rcode_noerror;
if (tsig.error != dns_tsigerror_badtime) {
tsig.otherlen = 0;
tsig.other = NULL;
} else {
isc_buffer_t otherbuf;
tsig.otherlen = BADTIMELEN;
tsig.other = badtimedata;
isc_buffer_init(&otherbuf, tsig.other, tsig.otherlen);
buffer_putuint48(&otherbuf, tsig.timesigned);
}
if (key->key != NULL && tsig.error != dns_tsigerror_badsig) {
unsigned char header[DNS_MESSAGE_HEADERLEN];
isc_buffer_t headerbuf;
ret = dst_context_create(key->key, mctx, &ctx);
if (ret != ISC_R_SUCCESS)
return (ret);
/*
* If this is a response, digest the query signature.
*/
if (is_response(msg)) {
dns_rdata_t querytsigrdata = DNS_RDATA_INIT;
ret = dns_rdataset_first(msg->querytsig);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
dns_rdataset_current(msg->querytsig, &querytsigrdata);
ret = dns_rdata_tostruct(&querytsigrdata, &querytsig,
NULL);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
isc_buffer_putuint16(&databuf, querytsig.siglen);
if (isc_buffer_availablelength(&databuf) <
querytsig.siglen)
{
ret = ISC_R_NOSPACE;
goto cleanup_context;
}
isc_buffer_putmem(&databuf, querytsig.signature,
querytsig.siglen);
isc_buffer_usedregion(&databuf, &r);
ret = dst_context_adddata(ctx, &r);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
}
/*
* Digest the header.
*/
isc_buffer_init(&headerbuf, header, sizeof(header));
dns_message_renderheader(msg, &headerbuf);
isc_buffer_usedregion(&headerbuf, &r);
ret = dst_context_adddata(ctx, &r);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
/*
* Digest the remainder of the message.
*/
isc_buffer_usedregion(msg->buffer, &r);
isc_region_consume(&r, DNS_MESSAGE_HEADERLEN);
ret = dst_context_adddata(ctx, &r);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
if (msg->tcp_continuation == 0) {
/*
* Digest the name, class, ttl, alg.
*/
dns_name_toregion(&key->name, &r);
ret = dst_context_adddata(ctx, &r);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
isc_buffer_clear(&databuf);
isc_buffer_putuint16(&databuf, dns_rdataclass_any);
isc_buffer_putuint32(&databuf, 0); /* ttl */
isc_buffer_usedregion(&databuf, &r);
ret = dst_context_adddata(ctx, &r);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
dns_name_toregion(&tsig.algorithm, &r);
ret = dst_context_adddata(ctx, &r);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
}
/* Digest the timesigned and fudge */
isc_buffer_clear(&databuf);
if (tsig.error == dns_tsigerror_badtime)
tsig.timesigned = querytsig.timesigned;
buffer_putuint48(&databuf, tsig.timesigned);
isc_buffer_putuint16(&databuf, tsig.fudge);
isc_buffer_usedregion(&databuf, &r);
ret = dst_context_adddata(ctx, &r);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
if (msg->tcp_continuation == 0) {
/*
* Digest the error and other data length.
*/
isc_buffer_clear(&databuf);
isc_buffer_putuint16(&databuf, tsig.error);
isc_buffer_putuint16(&databuf, tsig.otherlen);
isc_buffer_usedregion(&databuf, &r);
ret = dst_context_adddata(ctx, &r);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
/*
* Digest the error and other data.
*/
if (tsig.otherlen > 0) {
r.length = tsig.otherlen;
r.base = tsig.other;
ret = dst_context_adddata(ctx, &r);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
}
}
ret = dst_key_sigsize(key->key, &sigsize);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
tsig.signature = (unsigned char *) isc_mem_get(mctx, sigsize);
if (tsig.signature == NULL) {
ret = ISC_R_NOMEMORY;
goto cleanup_context;
}
isc_buffer_init(&sigbuf, tsig.signature, sigsize);
ret = dst_context_sign(ctx, &sigbuf);
if (ret != ISC_R_SUCCESS)
goto cleanup_signature;
dst_context_destroy(&ctx);
tsig.siglen = isc_buffer_usedlength(&sigbuf);
} else {
tsig.siglen = 0;
tsig.signature = NULL;
}
rdata = NULL;
ret = dns_message_gettemprdata(msg, &rdata);
if (ret != ISC_R_SUCCESS)
goto cleanup_signature;
ret = isc_buffer_allocate(msg->mctx, &dynbuf, 512);
if (ret != ISC_R_SUCCESS)
goto cleanup_signature;
ret = dns_rdata_fromstruct(rdata, dns_rdataclass_any,
dns_rdatatype_tsig, &tsig, dynbuf);
if (ret != ISC_R_SUCCESS)
goto cleanup_dynbuf;
dns_message_takebuffer(msg, &dynbuf);
if (tsig.signature != NULL) {
isc_mem_put(mctx, tsig.signature, sigsize);
tsig.signature = NULL;
}
owner = NULL;
ret = dns_message_gettempname(msg, &owner);
if (ret != ISC_R_SUCCESS)
goto cleanup_dynbuf;
dns_name_init(owner, NULL);
ret = dns_name_dup(&key->name, msg->mctx, owner);
if (ret != ISC_R_SUCCESS)
goto cleanup_owner;
datalist = NULL;
ret = dns_message_gettemprdatalist(msg, &datalist);
if (ret != ISC_R_SUCCESS)
goto cleanup_owner;
datalist->rdclass = dns_rdataclass_any;
datalist->type = dns_rdatatype_tsig;
datalist->covers = 0;
datalist->ttl = 0;
ISC_LIST_INIT(datalist->rdata);
ISC_LIST_APPEND(datalist->rdata, rdata, link);
dataset = NULL;
ret = dns_message_gettemprdataset(msg, &dataset);
if (ret != ISC_R_SUCCESS)
goto cleanup_owner;
dns_rdataset_init(dataset);
RUNTIME_CHECK(dns_rdatalist_tordataset(datalist, dataset)
== ISC_R_SUCCESS);
msg->tsig = dataset;
msg->tsigname = owner;
return (ISC_R_SUCCESS);
cleanup_owner:
if (owner != NULL)
dns_message_puttempname(msg, &owner);
cleanup_dynbuf:
if (dynbuf != NULL)
isc_buffer_free(&dynbuf);
cleanup_signature:
if (tsig.signature != NULL)
isc_mem_put(mctx, tsig.signature, sigsize);
cleanup_context:
if (ctx != NULL)
dst_context_destroy(&ctx);
return (ret);
}
isc_result_t
dns_dnssec_verifymessage(isc_buffer_t *source, dns_message_t *msg,
dst_key_t *key)
{
dns_rdata_sig_t sig; /* SIG(0) */
unsigned char header[DNS_MESSAGE_HEADERLEN];
dns_rdata_t rdata = DNS_RDATA_INIT;
isc_region_t r, source_r, sig_r, header_r;
isc_stdtime_t now;
dst_context_t *ctx = NULL;
isc_mem_t *mctx;
isc_result_t result;
isc_uint16_t addcount;
isc_boolean_t signeedsfree = ISC_FALSE;
REQUIRE(source != NULL);
REQUIRE(msg != NULL);
REQUIRE(key != NULL);
mctx = msg->mctx;
msg->verify_attempted = 1;
if (is_response(msg)) {
if (msg->query.base == NULL)
return (DNS_R_UNEXPECTEDTSIG);
}
isc_buffer_usedregion(source, &source_r);
RETERR(dns_rdataset_first(msg->sig0));
dns_rdataset_current(msg->sig0, &rdata);
RETERR(dns_rdata_tostruct(&rdata, &sig, NULL));
signeedsfree = ISC_TRUE;
if (sig.labels != 0) {
result = DNS_R_SIGINVALID;
goto failure;
}
if (isc_serial_lt(sig.timeexpire, sig.timesigned)) {
result = DNS_R_SIGINVALID;
msg->sig0status = dns_tsigerror_badtime;
goto failure;
}
isc_stdtime_get(&now);
if (isc_serial_lt((isc_uint32_t)now, sig.timesigned)) {
result = DNS_R_SIGFUTURE;
msg->sig0status = dns_tsigerror_badtime;
goto failure;
}
else if (isc_serial_lt(sig.timeexpire, (isc_uint32_t)now)) {
result = DNS_R_SIGEXPIRED;
msg->sig0status = dns_tsigerror_badtime;
goto failure;
}
if (!dns_name_equal(dst_key_name(key), &sig.signer)) {
result = DNS_R_SIGINVALID;
msg->sig0status = dns_tsigerror_badkey;
goto failure;
}
RETERR(dst_context_create(key, mctx, &ctx));
/*
* Digest the SIG(0) record, except for the signature.
*/
dns_rdata_toregion(&rdata, &r);
r.length -= sig.siglen;
RETERR(dst_context_adddata(ctx, &r));
/*
* If this is a response, digest the query.
*/
if (is_response(msg))
RETERR(dst_context_adddata(ctx, &msg->query));
/*
* Extract the header.
*/
memcpy(header, source_r.base, DNS_MESSAGE_HEADERLEN);
/*
* Decrement the additional field counter.
*/
memcpy(&addcount, &header[DNS_MESSAGE_HEADERLEN - 2], 2);
addcount = htons((isc_uint16_t)(ntohs(addcount) - 1));
memcpy(&header[DNS_MESSAGE_HEADERLEN - 2], &addcount, 2);
/*
* Digest the modified header.
*/
header_r.base = (unsigned char *) header;
header_r.length = DNS_MESSAGE_HEADERLEN;
RETERR(dst_context_adddata(ctx, &header_r));
/*
* Digest all non-SIG(0) records.
*/
r.base = source_r.base + DNS_MESSAGE_HEADERLEN;
r.length = msg->sigstart - DNS_MESSAGE_HEADERLEN;
RETERR(dst_context_adddata(ctx, &r));
sig_r.base = sig.signature;
sig_r.length = sig.siglen;
result = dst_context_verify(ctx, &sig_r);
if (result != ISC_R_SUCCESS) {
msg->sig0status = dns_tsigerror_badsig;
goto failure;
}
msg->verified_sig = 1;
dst_context_destroy(&ctx);
dns_rdata_freestruct(&sig);
return (ISC_R_SUCCESS);
failure:
if (signeedsfree)
dns_rdata_freestruct(&sig);
if (ctx != NULL)
dst_context_destroy(&ctx);
return (result);
}
isc_result_t
dns_dnssec_signmessage(dns_message_t *msg, dst_key_t *key) {
dns_rdata_sig_t sig; /* SIG(0) */
unsigned char data[512];
unsigned char header[DNS_MESSAGE_HEADERLEN];
isc_buffer_t headerbuf, databuf, sigbuf;
unsigned int sigsize;
isc_buffer_t *dynbuf = NULL;
dns_rdata_t *rdata;
dns_rdatalist_t *datalist;
dns_rdataset_t *dataset;
isc_region_t r;
isc_stdtime_t now;
dst_context_t *ctx = NULL;
isc_mem_t *mctx;
isc_result_t result;
isc_boolean_t signeedsfree = ISC_TRUE;
REQUIRE(msg != NULL);
REQUIRE(key != NULL);
if (is_response(msg))
REQUIRE(msg->query.base != NULL);
mctx = msg->mctx;
memset(&sig, 0, sizeof(sig));
sig.mctx = mctx;
sig.common.rdclass = dns_rdataclass_any;
sig.common.rdtype = dns_rdatatype_sig; /* SIG(0) */
ISC_LINK_INIT(&sig.common, link);
sig.covered = 0;
sig.algorithm = dst_key_alg(key);
sig.labels = 0; /* the root name */
sig.originalttl = 0;
isc_stdtime_get(&now);
sig.timesigned = now - DNS_TSIG_FUDGE;
sig.timeexpire = now + DNS_TSIG_FUDGE;
sig.keyid = dst_key_id(key);
dns_name_init(&sig.signer, NULL);
dns_name_clone(dst_key_name(key), &sig.signer);
sig.siglen = 0;
sig.signature = NULL;
isc_buffer_init(&databuf, data, sizeof(data));
RETERR(dst_context_create(key, mctx, &ctx));
/*
* Digest the fields of the SIG - we can cheat and use
* dns_rdata_fromstruct. Since siglen is 0, the digested data
* is identical to dns format.
*/
RETERR(dns_rdata_fromstruct(NULL, dns_rdataclass_any,
dns_rdatatype_sig /* SIG(0) */,
&sig, &databuf));
isc_buffer_usedregion(&databuf, &r);
RETERR(dst_context_adddata(ctx, &r));
/*
* If this is a response, digest the query.
*/
if (is_response(msg))
RETERR(dst_context_adddata(ctx, &msg->query));
/*
* Digest the header.
*/
isc_buffer_init(&headerbuf, header, sizeof(header));
dns_message_renderheader(msg, &headerbuf);
isc_buffer_usedregion(&headerbuf, &r);
RETERR(dst_context_adddata(ctx, &r));
/*
* Digest the remainder of the message.
*/
isc_buffer_usedregion(msg->buffer, &r);
isc_region_consume(&r, DNS_MESSAGE_HEADERLEN);
RETERR(dst_context_adddata(ctx, &r));
RETERR(dst_key_sigsize(key, &sigsize));
sig.siglen = sigsize;
sig.signature = (unsigned char *) isc_mem_get(mctx, sig.siglen);
if (sig.signature == NULL) {
result = ISC_R_NOMEMORY;
goto failure;
}
isc_buffer_init(&sigbuf, sig.signature, sig.siglen);
RETERR(dst_context_sign(ctx, &sigbuf));
dst_context_destroy(&ctx);
rdata = NULL;
RETERR(dns_message_gettemprdata(msg, &rdata));
RETERR(isc_buffer_allocate(msg->mctx, &dynbuf, 1024));
RETERR(dns_rdata_fromstruct(rdata, dns_rdataclass_any,
dns_rdatatype_sig /* SIG(0) */,
&sig, dynbuf));
isc_mem_put(mctx, sig.signature, sig.siglen);
signeedsfree = ISC_FALSE;
dns_message_takebuffer(msg, &dynbuf);
datalist = NULL;
RETERR(dns_message_gettemprdatalist(msg, &datalist));
datalist->rdclass = dns_rdataclass_any;
datalist->type = dns_rdatatype_sig; /* SIG(0) */
datalist->covers = 0;
datalist->ttl = 0;
ISC_LIST_INIT(datalist->rdata);
ISC_LIST_APPEND(datalist->rdata, rdata, link);
dataset = NULL;
RETERR(dns_message_gettemprdataset(msg, &dataset));
dns_rdataset_init(dataset);
RUNTIME_CHECK(dns_rdatalist_tordataset(datalist, dataset) == ISC_R_SUCCESS);
msg->sig0 = dataset;
return (ISC_R_SUCCESS);
failure:
if (dynbuf != NULL)
isc_buffer_free(&dynbuf);
if (signeedsfree)
isc_mem_put(mctx, sig.signature, sig.siglen);
if (ctx != NULL)
dst_context_destroy(&ctx);
return (result);
}
isc_result_t
dns_dnssec_verify2(dns_name_t *name, dns_rdataset_t *set, dst_key_t *key,
isc_boolean_t ignoretime, isc_mem_t *mctx,
dns_rdata_t *sigrdata, dns_name_t *wild)
{
dns_rdata_rrsig_t sig;
dns_fixedname_t fnewname;
isc_region_t r;
isc_buffer_t envbuf;
dns_rdata_t *rdatas;
int nrdatas, i;
isc_stdtime_t now;
isc_result_t ret;
unsigned char data[300];
dst_context_t *ctx = NULL;
int labels = 0;
isc_uint32_t flags;
REQUIRE(name != NULL);
REQUIRE(set != NULL);
REQUIRE(key != NULL);
REQUIRE(mctx != NULL);
REQUIRE(sigrdata != NULL && sigrdata->type == dns_rdatatype_rrsig);
ret = dns_rdata_tostruct(sigrdata, &sig, NULL);
if (ret != ISC_R_SUCCESS)
return (ret);
if (isc_serial_lt(sig.timeexpire, sig.timesigned))
return (DNS_R_SIGINVALID);
if (!ignoretime) {
isc_stdtime_get(&now);
/*
* Is SIG temporally valid?
*/
if (isc_serial_lt((isc_uint32_t)now, sig.timesigned))
return (DNS_R_SIGFUTURE);
else if (isc_serial_lt(sig.timeexpire, (isc_uint32_t)now))
return (DNS_R_SIGEXPIRED);
}
/*
* Is the key allowed to sign data?
*/
flags = dst_key_flags(key);
if (flags & DNS_KEYTYPE_NOAUTH)
return (DNS_R_KEYUNAUTHORIZED);
if ((flags & DNS_KEYFLAG_OWNERMASK) != DNS_KEYOWNER_ZONE)
return (DNS_R_KEYUNAUTHORIZED);
ret = dst_context_create(key, mctx, &ctx);
if (ret != ISC_R_SUCCESS)
goto cleanup_struct;
/*
* Digest the SIG rdata (not including the signature).
*/
ret = digest_sig(ctx, sigrdata, &sig);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
/*
* If the name is an expanded wildcard, use the wildcard name.
*/
dns_fixedname_init(&fnewname);
labels = dns_name_countlabels(name) - 1;
RUNTIME_CHECK(dns_name_downcase(name, dns_fixedname_name(&fnewname),
NULL) == ISC_R_SUCCESS);
if (labels - sig.labels > 0)
dns_name_split(dns_fixedname_name(&fnewname), sig.labels + 1,
NULL, dns_fixedname_name(&fnewname));
dns_name_toregion(dns_fixedname_name(&fnewname), &r);
/*
* Create an envelope for each rdata: <name|type|class|ttl>.
*/
isc_buffer_init(&envbuf, data, sizeof(data));
if (labels - sig.labels > 0) {
isc_buffer_putuint8(&envbuf, 1);
isc_buffer_putuint8(&envbuf, '*');
memcpy(data + 2, r.base, r.length);
}
else
memcpy(data, r.base, r.length);
isc_buffer_add(&envbuf, r.length);
isc_buffer_putuint16(&envbuf, set->type);
isc_buffer_putuint16(&envbuf, set->rdclass);
isc_buffer_putuint32(&envbuf, sig.originalttl);
ret = rdataset_to_sortedarray(set, mctx, &rdatas, &nrdatas);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
isc_buffer_usedregion(&envbuf, &r);
for (i = 0; i < nrdatas; i++) {
isc_uint16_t len;
isc_buffer_t lenbuf;
isc_region_t lenr;
/*
* Skip duplicates.
*/
if (i > 0 && dns_rdata_compare(&rdatas[i], &rdatas[i-1]) == 0)
continue;
/*
* Digest the envelope.
*/
ret = dst_context_adddata(ctx, &r);
if (ret != ISC_R_SUCCESS)
goto cleanup_array;
/*
* Digest the rdata length.
*/
isc_buffer_init(&lenbuf, &len, sizeof(len));
INSIST(rdatas[i].length < 65536);
isc_buffer_putuint16(&lenbuf, (isc_uint16_t)rdatas[i].length);
isc_buffer_usedregion(&lenbuf, &lenr);
/*
* Digest the rdata.
*/
ret = dst_context_adddata(ctx, &lenr);
if (ret != ISC_R_SUCCESS)
goto cleanup_array;
ret = dns_rdata_digest(&rdatas[i], digest_callback, ctx);
if (ret != ISC_R_SUCCESS)
goto cleanup_array;
}
r.base = sig.signature;
r.length = sig.siglen;
ret = dst_context_verify(ctx, &r);
if (ret == DST_R_VERIFYFAILURE)
ret = DNS_R_SIGINVALID;
cleanup_array:
isc_mem_put(mctx, rdatas, nrdatas * sizeof(dns_rdata_t));
cleanup_context:
dst_context_destroy(&ctx);
cleanup_struct:
dns_rdata_freestruct(&sig);
if (ret == ISC_R_SUCCESS && labels - sig.labels > 0) {
if (wild != NULL)
RUNTIME_CHECK(dns_name_concatenate(dns_wildcardname,
dns_fixedname_name(&fnewname),
wild, NULL) == ISC_R_SUCCESS);
ret = DNS_R_FROMWILDCARD;
}
return (ret);
}
isc_result_t
dns_dnssec_sign(dns_name_t *name, dns_rdataset_t *set, dst_key_t *key,
isc_stdtime_t *inception, isc_stdtime_t *expire,
isc_mem_t *mctx, isc_buffer_t *buffer, dns_rdata_t *sigrdata)
{
dns_rdata_rrsig_t sig;
dns_rdata_t tmpsigrdata;
dns_rdata_t *rdatas;
int nrdatas, i;
isc_buffer_t sigbuf, envbuf;
isc_region_t r;
dst_context_t *ctx = NULL;
isc_result_t ret;
isc_buffer_t *databuf = NULL;
char data[256 + 8];
isc_uint32_t flags;
unsigned int sigsize;
dns_fixedname_t fnewname;
REQUIRE(name != NULL);
REQUIRE(dns_name_countlabels(name) <= 255);
REQUIRE(set != NULL);
REQUIRE(key != NULL);
REQUIRE(inception != NULL);
REQUIRE(expire != NULL);
REQUIRE(mctx != NULL);
REQUIRE(sigrdata != NULL);
if (*inception >= *expire)
return (DNS_R_INVALIDTIME);
/*
* Is the key allowed to sign data?
*/
flags = dst_key_flags(key);
if (flags & DNS_KEYTYPE_NOAUTH)
return (DNS_R_KEYUNAUTHORIZED);
if ((flags & DNS_KEYFLAG_OWNERMASK) != DNS_KEYOWNER_ZONE)
return (DNS_R_KEYUNAUTHORIZED);
sig.mctx = mctx;
sig.common.rdclass = set->rdclass;
sig.common.rdtype = dns_rdatatype_rrsig;
ISC_LINK_INIT(&sig.common, link);
dns_name_init(&sig.signer, NULL);
dns_name_clone(dst_key_name(key), &sig.signer);
sig.covered = set->type;
sig.algorithm = dst_key_alg(key);
sig.labels = dns_name_countlabels(name) - 1;
if (dns_name_iswildcard(name))
sig.labels--;
sig.originalttl = set->ttl;
sig.timesigned = *inception;
sig.timeexpire = *expire;
sig.keyid = dst_key_id(key);
ret = dst_key_sigsize(key, &sigsize);
if (ret != ISC_R_SUCCESS)
return (ret);
sig.siglen = sigsize;
/*
* The actual contents of sig.signature are not important yet, since
* they're not used in digest_sig().
*/
sig.signature = isc_mem_get(mctx, sig.siglen);
if (sig.signature == NULL)
return (ISC_R_NOMEMORY);
ret = isc_buffer_allocate(mctx, &databuf, sigsize + 256 + 18);
if (ret != ISC_R_SUCCESS)
goto cleanup_signature;
dns_rdata_init(&tmpsigrdata);
ret = dns_rdata_fromstruct(&tmpsigrdata, sig.common.rdclass,
sig.common.rdtype, &sig, databuf);
if (ret != ISC_R_SUCCESS)
goto cleanup_databuf;
ret = dst_context_create(key, mctx, &ctx);
if (ret != ISC_R_SUCCESS)
goto cleanup_databuf;
/*
* Digest the SIG rdata.
*/
ret = digest_sig(ctx, &tmpsigrdata, &sig);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
dns_fixedname_init(&fnewname);
RUNTIME_CHECK(dns_name_downcase(name, dns_fixedname_name(&fnewname),
NULL) == ISC_R_SUCCESS);
dns_name_toregion(dns_fixedname_name(&fnewname), &r);
/*
* Create an envelope for each rdata: <name|type|class|ttl>.
*/
isc_buffer_init(&envbuf, data, sizeof(data));
memcpy(data, r.base, r.length);
isc_buffer_add(&envbuf, r.length);
isc_buffer_putuint16(&envbuf, set->type);
isc_buffer_putuint16(&envbuf, set->rdclass);
isc_buffer_putuint32(&envbuf, set->ttl);
ret = rdataset_to_sortedarray(set, mctx, &rdatas, &nrdatas);
if (ret != ISC_R_SUCCESS)
goto cleanup_context;
isc_buffer_usedregion(&envbuf, &r);
for (i = 0; i < nrdatas; i++) {
isc_uint16_t len;
isc_buffer_t lenbuf;
isc_region_t lenr;
/*
* Skip duplicates.
*/
if (i > 0 && dns_rdata_compare(&rdatas[i], &rdatas[i-1]) == 0)
continue;
/*
* Digest the envelope.
*/
ret = dst_context_adddata(ctx, &r);
if (ret != ISC_R_SUCCESS)
goto cleanup_array;
/*
* Digest the length of the rdata.
*/
isc_buffer_init(&lenbuf, &len, sizeof(len));
INSIST(rdatas[i].length < 65536);
isc_buffer_putuint16(&lenbuf, (isc_uint16_t)rdatas[i].length);
isc_buffer_usedregion(&lenbuf, &lenr);
ret = dst_context_adddata(ctx, &lenr);
if (ret != ISC_R_SUCCESS)
goto cleanup_array;
/*
* Digest the rdata.
*/
ret = dns_rdata_digest(&rdatas[i], digest_callback, ctx);
if (ret != ISC_R_SUCCESS)
goto cleanup_array;
}
isc_buffer_init(&sigbuf, sig.signature, sig.siglen);
ret = dst_context_sign(ctx, &sigbuf);
if (ret != ISC_R_SUCCESS)
goto cleanup_array;
isc_buffer_usedregion(&sigbuf, &r);
if (r.length != sig.siglen) {
ret = ISC_R_NOSPACE;
goto cleanup_array;
}
memcpy(sig.signature, r.base, sig.siglen);
ret = dns_rdata_fromstruct(sigrdata, sig.common.rdclass,
sig.common.rdtype, &sig, buffer);
cleanup_array:
isc_mem_put(mctx, rdatas, nrdatas * sizeof(dns_rdata_t));
cleanup_context:
dst_context_destroy(&ctx);
cleanup_databuf:
isc_buffer_free(&databuf);
cleanup_signature:
isc_mem_put(mctx, sig.signature, sig.siglen);
return (ret);
}
