SECStatus
ssl3_SendECDHServerKeyExchange(sslSocket *ss)
{
SECStatus rv = SECFailure;
int length;
PRBool isTLS12;
SECItem signed_hash = { siBuffer, NULL, 0 };
SSLHashType hashAlg = ssl_hash_none;
SSL3Hashes hashes;
SECItem ec_params = { siBuffer, NULL, 0 };
unsigned char paramBuf[3];
const sslNamedGroupDef *ecGroup;
sslEphemeralKeyPair *keyPair;
SECKEYPublicKey *pubKey;
/* Generate ephemeral ECDH key pair and send the public key */
ecGroup = ssl_GetECGroupForServerSocket(ss);
if (!ecGroup) {
goto loser;
}
PORT_Assert(PR_CLIST_IS_EMPTY(&ss->ephemeralKeyPairs));
if (ss->opt.reuseServerECDHEKey) {
rv = ssl_CreateStaticECDHEKey(ss, ecGroup);
if (rv != SECSuccess) {
goto loser;
}
keyPair = (sslEphemeralKeyPair *)PR_NEXT_LINK(&ss->ephemeralKeyPairs);
} else {
rv = ssl_CreateECDHEphemeralKeyPair(ss, ecGroup, &keyPair);
if (rv != SECSuccess) {
goto loser;
}
PR_APPEND_LINK(&keyPair->link, &ss->ephemeralKeyPairs);
}
PORT_Assert(keyPair);
if (!keyPair) {
PORT_SetError(SSL_ERROR_SERVER_KEY_EXCHANGE_FAILURE);
return SECFailure;
}
ec_params.len = sizeof(paramBuf);
ec_params.data = paramBuf;
PORT_Assert(keyPair->group);
PORT_Assert(keyPair->group->keaType == ssl_kea_ecdh);
ec_params.data[0] = ec_type_named;
ec_params.data[1] = keyPair->group->name >> 8;
ec_params.data[2] = keyPair->group->name & 0xff;
pubKey = keyPair->keys->pubKey;
if (ss->ssl3.pwSpec->version == SSL_LIBRARY_VERSION_TLS_1_2) {
hashAlg = ssl_SignatureSchemeToHashType(ss->ssl3.hs.signatureScheme);
} else {
/* Use ssl_hash_none to represent the MD5+SHA1 combo. */
hashAlg = ssl_hash_none;
}
rv = ssl3_ComputeECDHKeyHash(hashAlg, ec_params,
pubKey->u.ec.publicValue,
&ss->ssl3.hs.client_random,
&ss->ssl3.hs.server_random,
&hashes);
if (rv != SECSuccess) {
ssl_MapLowLevelError(SSL_ERROR_SERVER_KEY_EXCHANGE_FAILURE);
goto loser;
}
isTLS12 = (PRBool)(ss->ssl3.pwSpec->version >= SSL_LIBRARY_VERSION_TLS_1_2);
rv = ssl3_SignHashes(ss, &hashes,
ss->sec.serverCert->serverKeyPair->privKey, &signed_hash);
if (rv != SECSuccess) {
goto loser; /* ssl3_SignHashes has set err. */
}
if (signed_hash.data == NULL) {
/* how can this happen and rv == SECSuccess ?? */
PORT_SetError(SSL_ERROR_SERVER_KEY_EXCHANGE_FAILURE);
goto loser;
}
length = ec_params.len +
1 + pubKey->u.ec.publicValue.len +
(isTLS12 ? 2 : 0) + 2 + signed_hash.len;
rv = ssl3_AppendHandshakeHeader(ss, server_key_exchange, length);
if (rv != SECSuccess) {
goto loser; /* err set by AppendHandshake. */
}
rv = ssl3_AppendHandshake(ss, ec_params.data, ec_params.len);
if (rv != SECSuccess) {
goto loser; /* err set by AppendHandshake. */
}
rv = ssl3_AppendHandshakeVariable(ss, pubKey->u.ec.publicValue.data,
pubKey->u.ec.publicValue.len, 1);
if (rv != SECSuccess) {
goto loser; /* err set by AppendHandshake. */
}
if (isTLS12) {
rv = ssl3_AppendHandshakeNumber(ss, ss->ssl3.hs.signatureScheme, 2);
if (rv != SECSuccess) {
goto loser; /* err set by AppendHandshake. */
}
}
rv = ssl3_AppendHandshakeVariable(ss, signed_hash.data,
signed_hash.len, 2);
if (rv != SECSuccess) {
goto loser; /* err set by AppendHandshake. */
}
PORT_Free(signed_hash.data);
return SECSuccess;
loser:
if (signed_hash.data != NULL)
PORT_Free(signed_hash.data);
return SECFailure;
}
/* Send our Supported Groups extension. */
PRInt32
ssl_SendSupportedGroupsXtn(sslSocket *ss, PRBool append, PRUint32 maxBytes)
{
PRInt32 extension_length;
unsigned char enabledGroups[64];
unsigned int enabledGroupsLen = 0;
unsigned int i;
PRBool ec;
PRBool ff = PR_FALSE;
if (!ss)
return 0;
/* We only send FF supported groups if we require DH named groups
* or if TLS 1.3 is a possibility. */
if (ss->vrange.max < SSL_LIBRARY_VERSION_TLS_1_3) {
ec = ssl_IsECCEnabled(ss);
if (ss->opt.requireDHENamedGroups) {
ff = ssl_IsDHEEnabled(ss);
}
if (!ec && !ff)
return 0;
} else {
ec = ff = PR_TRUE;
}
PORT_Assert(sizeof(enabledGroups) > SSL_NAMED_GROUP_COUNT * 2);
for (i = 0; i < SSL_NAMED_GROUP_COUNT; ++i) {
const sslNamedGroupDef *group = ss->namedGroupPreferences[i];
if (!group) {
continue;
}
if (group->keaType == ssl_kea_ecdh && !ec) {
continue;
}
if (group->keaType == ssl_kea_dh && !ff) {
continue;
}
if (append) {
(void)ssl_EncodeUintX(group->name, 2, &enabledGroups[enabledGroupsLen]);
}
enabledGroupsLen += 2;
}
if (enabledGroupsLen == 0) {
return 0;
}
extension_length =
2 /* extension type */ +
2 /* extension length */ +
2 /* enabled groups length */ +
enabledGroupsLen;
if (maxBytes < (PRUint32)extension_length) {
return 0;
}
if (append) {
SECStatus rv;
rv = ssl3_AppendHandshakeNumber(ss, ssl_supported_groups_xtn, 2);
if (rv != SECSuccess)
return -1;
rv = ssl3_AppendHandshakeNumber(ss, extension_length - 4, 2);
if (rv != SECSuccess)
return -1;
rv = ssl3_AppendHandshakeVariable(ss, enabledGroups,
enabledGroupsLen, 2);
if (rv != SECSuccess)
return -1;
if (!ss->sec.isServer) {
TLSExtensionData *xtnData = &ss->xtnData;
xtnData->advertised[xtnData->numAdvertised++] =
ssl_supported_groups_xtn;
}
}
return extension_length;
}
