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chromium / chromium / src / net / third_party / nss / 1791e3bd3cbcab365547a5585b61ca29c4d0112e / . / ssl / tls13con.c
blob: 4bb136a5eefbe4173acf93fb2cbf679baf4a8526 [file] [log] [blame]
/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
* TLS 1.3 Protocol
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "stdarg.h"
#include "cert.h"
#include "ssl.h"
#include "keyhi.h"
#include "pk11func.h"
#include "secitem.h"
#include "sslimpl.h"
#include "sslproto.h"
#include "sslerr.h"
#include "tls13hkdf.h"
#include "tls13con.h"
typedef enum {
TrafficKeyEarlyData,
TrafficKeyHandshake,
TrafficKeyApplicationData
} TrafficKeyType;
typedef enum {
InstallCipherSpecRead,
InstallCipherSpecWrite,
InstallCipherSpecBoth
} InstallCipherSpecDirection;
#define MAX_FINISHED_SIZE 64
static SECStatus tls13_InitializeHandshakeEncryption(sslSocket *ss);
static SECStatus tls13_InstallCipherSpec(
sslSocket *ss, InstallCipherSpecDirection direction);
static SECStatus tls13_InitCipherSpec(
sslSocket *ss, TrafficKeyType type, InstallCipherSpecDirection install);
static SECStatus tls13_AESGCM(
ssl3KeyMaterial *keys,
PRBool doDecrypt,
unsigned char *out, int *outlen, int maxout,
const unsigned char *in, int inlen,
const unsigned char *additionalData, int additionalDataLen);
static SECStatus tls13_SendEncryptedExtensions(sslSocket *ss);
static SECStatus tls13_HandleEncryptedExtensions(sslSocket *ss, SSL3Opaque *b,
PRUint32 length);
static SECStatus tls13_HandleCertificate(
sslSocket *ss, SSL3Opaque *b, PRUint32 length);
static SECStatus tls13_HandleCertificateRequest(sslSocket *ss, SSL3Opaque *b,
PRUint32 length);
static SECStatus tls13_HandleCertificateStatus(sslSocket *ss, SSL3Opaque *b,
PRUint32 length);
static SECStatus tls13_HandleCertificateVerify(
sslSocket *ss, SSL3Opaque *b, PRUint32 length,
SSL3Hashes *hashes);
static SECStatus tls13_HkdfExtractSharedKey(sslSocket *ss, PK11SymKey *key,
SharedSecretType keyType);
static SECStatus tls13_SendFinished(sslSocket *ss);
static SECStatus tls13_HandleFinished(sslSocket *ss, SSL3Opaque *b, PRUint32 length,
const SSL3Hashes *hashes);
static SECStatus tls13_HandleNewSessionTicket(sslSocket *ss, SSL3Opaque *b,
PRUint32 length);
static SECStatus tls13_ComputeSecrets1(sslSocket *ss);
static SECStatus tls13_ComputeFinished(
sslSocket *ss, const SSL3Hashes *hashes,
PRBool sending,
PRUint8 *output, unsigned int *outputLen,
unsigned int maxOutputLen);
static SECStatus tls13_SendClientSecondRound(sslSocket *ss);
static SECStatus tls13_FinishHandshake(sslSocket *ss);
const char kHkdfLabelExpandedSs[] = "expanded static secret";
const char kHkdfLabelExpandedEs[] = "expanded ephemeral secret";
const char kHkdfLabelMasterSecret[] = "master secret";
const char kHkdfLabelTrafficSecret[] = "traffic secret";
const char kHkdfLabelClientFinishedSecret[] = "client finished";
const char kHkdfLabelServerFinishedSecret[] = "server finished";
const char kHkdfLabelResumptionMasterSecret[] = "resumption master secret";
const char kHkdfLabelExporterMasterSecret[] = "exporter master secret";
const char kHkdfPhaseEarlyHandshakeDataKeys[] = "early handshake key expansion";
const char kHkdfPhaseEarlyApplicationDataKeys[] = "early application data key expansion";
const char kHkdfPhaseHandshakeKeys[] = "handshake key expansion";
const char kHkdfPhaseApplicationDataKeys[] = "application data key expansion";
const char kHkdfPurposeClientWriteKey[] = "client write key";
const char kHkdfPurposeServerWriteKey[] = "server write key";
const char kHkdfPurposeClientWriteIv[] = "client write iv";
const char kHkdfPurposeServerWriteIv[] = "server write iv";
const char kClientFinishedLabel[] = "client finished";
const char kServerFinishedLabel[] = "server finished";
const SSL3ProtocolVersion kRecordVersion = 0x0301U;
#define FATAL_ERROR(ss, prError, desc) \
do { \
SSL_TRC(3, ("%d: TLS13[%d]: fatal error %d in %s (%s:%d)", \
SSL_GETPID(), ss->fd, prError, __func__, __FILE__, __LINE__)); \
tls13_FatalError(ss, prError, desc); \
} while (0)
#define UNIMPLEMENTED() \
do { \
SSL_TRC(3, ("%d: TLS13[%d]: unimplemented feature in %s (%s:%d)", \
SSL_GETPID(), ss->fd, __func__, __FILE__, __LINE__)); \
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE); \
PORT_Assert(0); \
return SECFailure; \
} while (0)
void
tls13_FatalError(sslSocket *ss, PRErrorCode prError, SSL3AlertDescription desc)
{
PORT_Assert(desc != internal_error); /* These should never happen */
(void)SSL3_SendAlert(ss, alert_fatal, desc);
PORT_SetError(prError);
}
#ifdef TRACE
#define STATE_CASE(a) \
case a: \
return #a
static char *
tls13_HandshakeState(SSL3WaitState st)
{
switch (st) {
STATE_CASE(wait_client_hello);
STATE_CASE(wait_client_cert);
STATE_CASE(wait_cert_verify);
STATE_CASE(wait_finished);
STATE_CASE(wait_server_hello);
STATE_CASE(wait_certificate_status);
STATE_CASE(wait_server_cert);
STATE_CASE(wait_cert_request);
STATE_CASE(wait_encrypted_extensions);
STATE_CASE(idle_handshake);
default:
break;
}
PORT_Assert(0);
return "unknown";
}
#endif
#define TLS13_WAIT_STATE_MASK 0x80
#define TLS13_BASE_WAIT_STATE(ws) (ws & ~TLS13_WAIT_STATE_MASK)
/* We don't mask idle_handshake because other parts of the code use it*/
#define TLS13_WAIT_STATE(ws) (ws == idle_handshake ? ws : ws | TLS13_WAIT_STATE_MASK)
#define TLS13_CHECK_HS_STATE(ss, err, ...) \
tls13_CheckHsState(ss, err, #err, __func__, __FILE__, __LINE__, \
__VA_ARGS__, \
wait_invalid)
void
tls13_SetHsState(sslSocket *ss, SSL3WaitState ws,
const char *func, const char *file, int line)
{
#ifdef TRACE
const char *new_state_name =
tls13_HandshakeState(ws);
SSL_TRC(3, ("%d: TLS13[%d]: state change from %s->%s in %s (%s:%d)",
SSL_GETPID(), ss->fd,
tls13_HandshakeState(TLS13_BASE_WAIT_STATE(ss->ssl3.hs.ws)),
new_state_name,
func, file, line));
#endif
ss->ssl3.hs.ws = TLS13_WAIT_STATE(ws);
}
static PRBool
tls13_InHsStateV(sslSocket *ss, va_list ap)
{
SSL3WaitState ws;
while ((ws = va_arg(ap, SSL3WaitState)) != wait_invalid) {
if (ws == TLS13_BASE_WAIT_STATE(ss->ssl3.hs.ws)) {
return PR_TRUE;
}
}
return PR_FALSE;
}
PRBool
tls13_InHsState(sslSocket *ss, ...)
{
PRBool found;
va_list ap;
va_start(ap, ss);
found = tls13_InHsStateV(ss, ap);
va_end(ap);
return found;
}
static SECStatus
tls13_CheckHsState(sslSocket *ss, int err, const char *error_name,
const char *func, const char *file, int line,
...)
{
va_list ap;
va_start(ap, line);
if (tls13_InHsStateV(ss, ap)) {
va_end(ap);
return SECSuccess;
}
va_end(ap);
SSL_TRC(3, ("%d: TLS13[%d]: error %s state is (%s) at %s (%s:%d)",
SSL_GETPID(), ss->fd,
error_name,
tls13_HandshakeState(TLS13_BASE_WAIT_STATE(ss->ssl3.hs.ws)),
func, file, line));
tls13_FatalError(ss, err, unexpected_message);
return SECFailure;
}
SSLHashType
tls13_GetHash(sslSocket *ss)
{
/* TODO(ekr@rtfm.com): This needs to actually be looked up. */
return ssl_hash_sha256;
}
CK_MECHANISM_TYPE
tls13_GetHkdfMechanism(sslSocket *ss)
{
/* TODO(ekr@rtfm.com): This needs to actually be looked up. */
return CKM_NSS_HKDF_SHA256;
}
static CK_MECHANISM_TYPE
tls13_GetHmacMechanism(sslSocket *ss)
{
/* TODO(ekr@rtfm.com): This needs to actually be looked up. */
return CKM_SHA256_HMAC;
}
/*
* Called from ssl3_SendClientHello
*/
SECStatus
tls13_SetupClientHello(sslSocket *ss)
{
SECStatus rv;
/* TODO(ekr@rtfm.com): Handle multiple curves here. */
ECName curves_to_try[] = { ec_secp256r1 };
PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
PORT_Assert(ss->opt.noLocks || ssl_HaveXmitBufLock(ss));
PORT_Assert(!ss->ephemeralECDHKeyPair);
rv = ssl3_CreateECDHEphemeralKeyPair(curves_to_try[0],
&ss->ephemeralECDHKeyPair);
if (rv != SECSuccess)
return rv;
return SECSuccess;
}
static SECStatus
tls13_HandleECDHEKeyShare(sslSocket *ss,
TLS13KeyShareEntry *entry,
SECKEYPrivateKey *privKey,
SharedSecretType type)
{
SECStatus rv;
SECKEYPublicKey *peerKey;
PK11SymKey *shared;
peerKey = tls13_ImportECDHKeyShare(ss, entry->key_exchange.data,
entry->key_exchange.len,
entry->group);
if (!peerKey)
return SECFailure; /* Error code set already. */
/* Compute shared key. */
shared = tls13_ComputeECDHSharedKey(ss, privKey, peerKey);
SECKEY_DestroyPublicKey(peerKey);
if (!shared) {
return SECFailure; /* Error code set already. */
}
/* Extract key. */
rv = tls13_HkdfExtractSharedKey(ss, shared, type);
PK11_FreeSymKey(shared);
return rv;
}
SECStatus
tls13_HandlePostHelloHandshakeMessage(sslSocket *ss, SSL3Opaque *b,
PRUint32 length, SSL3Hashes *hashesPtr)
{
/* TODO(ekr@rtfm.com): Would it be better to check all the states here? */
switch (ss->ssl3.hs.msg_type) {
case certificate:
return tls13_HandleCertificate(ss, b, length);
case certificate_status:
return tls13_HandleCertificateStatus(ss, b, length);
case certificate_request:
return tls13_HandleCertificateRequest(ss, b, length);
case certificate_verify:
return tls13_HandleCertificateVerify(ss, b, length, hashesPtr);
case encrypted_extensions:
return tls13_HandleEncryptedExtensions(ss, b, length);
case new_session_ticket:
return tls13_HandleNewSessionTicket(ss, b, length);
case finished:
return tls13_HandleFinished(ss, b, length, hashesPtr);
default:
FATAL_ERROR(ss, SSL_ERROR_RX_UNKNOWN_HANDSHAKE, unexpected_message);
return SECFailure;
}
PORT_Assert(0); /* Unreached */
return SECFailure;
}
/* Called from ssl3_HandleClientHello.
*
* Caller must hold Handshake and RecvBuf locks.
*/
SECStatus
tls13_HandleClientKeyShare(sslSocket *ss)
{
ECName expectedGroup;
SECStatus rv;
TLS13KeyShareEntry *found = NULL;
PRCList *cur_p;
SSL_TRC(3, ("%d: TLS13[%d]: handle client_key_share handshake",
SSL_GETPID(), ss->fd));
PORT_Assert(ss->opt.noLocks || ssl_HaveRecvBufLock(ss));
PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
rv = ssl3_SetupPendingCipherSpec(ss);
if (rv != SECSuccess)
return SECFailure; /* Error code set below */
/* Figure out what group we expect */
switch (ss->ssl3.hs.kea_def->exchKeyType) {
#ifndef NSS_DISABLE_ECC
case ssl_kea_ecdh:
expectedGroup = ssl3_GetCurveNameForServerSocket(ss);
if (!expectedGroup) {
FATAL_ERROR(ss, SSL_ERROR_NO_CYPHER_OVERLAP,
handshake_failure);
return SECFailure;
}
break;
#endif
default:
/* Got an unknown or unsupported Key Exchange Algorithm.
* Can't happen. */
FATAL_ERROR(ss, SEC_ERROR_UNSUPPORTED_KEYALG,
internal_error);
return SECFailure;
}
/* Now walk through the keys until we find one for our group */
cur_p = PR_NEXT_LINK(&ss->ssl3.hs.remoteKeyShares);
while (cur_p != &ss->ssl3.hs.remoteKeyShares) {
TLS13KeyShareEntry *offer = (TLS13KeyShareEntry *)cur_p;
if (offer->group == expectedGroup) {
found = offer;
break;
}
cur_p = PR_NEXT_LINK(cur_p);
}
if (!found) {
/* No acceptable group. In future, we will need to correct the client.
* Currently just generate an error.
* TODO(ekr@rtfm.com): Write code to correct client.
*/
FATAL_ERROR(ss, SSL_ERROR_NO_CYPHER_OVERLAP, handshake_failure);
return SECFailure;
}
/* Generate our key */
rv = ssl3_CreateECDHEphemeralKeyPair(expectedGroup, &ss->ephemeralECDHKeyPair);
if (rv != SECSuccess)
return rv;
ss->sec.keaType = ss->ssl3.hs.kea_def->exchKeyType;
ss->sec.keaKeyBits = SECKEY_PublicKeyStrengthInBits(
ss->ephemeralECDHKeyPair->pubKey);
/* Register the sender */
rv = ssl3_RegisterServerHelloExtensionSender(ss, ssl_tls13_key_share_xtn,
tls13_ServerSendKeyShareXtn);
if (rv != SECSuccess)
return SECFailure; /* Error code set below */
rv = tls13_HandleECDHEKeyShare(ss, found,
ss->ephemeralECDHKeyPair->privKey,
EphemeralSharedSecret);
if (rv != SECSuccess)
return SECFailure; /* Error code set below */
return SECSuccess;
}
/*
* [draft-ietf-tls-tls13-11] Section 6.3.3.2
*
* opaque DistinguishedName<1..2^16-1>;
*
* struct {
* opaque certificate_extension_oid<1..2^8-1>;
* opaque certificate_extension_values<0..2^16-1>;
* } CertificateExtension;
*
* struct {
* opaque certificate_request_context<0..2^8-1>;
* SignatureAndHashAlgorithm
* supported_signature_algorithms<2..2^16-2>;
* DistinguishedName certificate_authorities<0..2^16-1>;
* CertificateExtension certificate_extensions<0..2^16-1>;
* } CertificateRequest;
*/
static SECStatus
tls13_SendCertificateRequest(sslSocket *ss)
{
SECStatus rv;
int calen;
SECItem *names;
int nnames;
SECItem *name;
int i;
PRUint8 sigAlgs[MAX_SIGNATURE_ALGORITHMS * 2];
unsigned int sigAlgsLength = 0;
int length;
SSL_TRC(3, ("%d: TLS13[%d]: begin send certificate_request",
SSL_GETPID(), ss->fd));
/* Fixed context value. */
ss->ssl3.hs.certReqContext[0] = 0;
ss->ssl3.hs.certReqContextLen = 1;
rv = ssl3_EncodeCertificateRequestSigAlgs(ss, sigAlgs, sizeof(sigAlgs),
&sigAlgsLength);
if (rv != SECSuccess) {
return rv;
}
ssl3_GetCertificateRequestCAs(ss, &calen, &names, &nnames);
length = 1 + ss->ssl3.hs.certReqContextLen +
2 + sigAlgsLength + 2 + calen + 2;
rv = ssl3_AppendHandshakeHeader(ss, certificate_request, length);
if (rv != SECSuccess) {
return rv; /* err set by AppendHandshake. */
}
rv = ssl3_AppendHandshakeVariable(ss, ss->ssl3.hs.certReqContext,
ss->ssl3.hs.certReqContextLen, 1);
if (rv != SECSuccess) {
return rv; /* err set by AppendHandshake. */
}
rv = ssl3_AppendHandshakeVariable(ss, sigAlgs, sigAlgsLength, 2);
if (rv != SECSuccess) {
return rv; /* err set by AppendHandshake. */
}
rv = ssl3_AppendHandshakeNumber(ss, calen, 2);
if (rv != SECSuccess) {
return rv; /* err set by AppendHandshake. */
}
for (i = 0, name = names; i < nnames; i++, name++) {
rv = ssl3_AppendHandshakeVariable(ss, name->data, name->len, 2);
if (rv != SECSuccess) {
return rv; /* err set by AppendHandshake. */
}
}
rv = ssl3_AppendHandshakeNumber(ss, 0, 2);
if (rv != SECSuccess) {
return rv; /* err set by AppendHandshake. */
}
return SECSuccess;
}
static SECStatus
tls13_HandleCertificateRequest(sslSocket *ss, SSL3Opaque *b, PRUint32 length)
{
SECStatus rv;
SECItem context = { siBuffer, NULL, 0 };
SECItem algorithms = { siBuffer, NULL, 0 };
PLArenaPool *arena;
CERTDistNames ca_list;
PRInt32 extensionsLength;
SSL_TRC(3, ("%d: TLS13[%d]: handle certificate_request sequence",
SSL_GETPID(), ss->fd));
PORT_Assert(ss->opt.noLocks || ssl_HaveRecvBufLock(ss));
PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
/* Client */
rv = TLS13_CHECK_HS_STATE(ss, SSL_ERROR_RX_UNEXPECTED_CERT_REQUEST, wait_cert_request);
if (rv != SECSuccess) {
return SECFailure;
}
PORT_Assert(ss->ssl3.clientCertChain == NULL);
PORT_Assert(ss->ssl3.clientCertificate == NULL);
PORT_Assert(ss->ssl3.clientPrivateKey == NULL);
rv = ssl3_ConsumeHandshakeVariable(ss, &context, 1, &b, &length);
if (rv != SECSuccess)
return SECFailure;
PORT_Assert(sizeof(ss->ssl3.hs.certReqContext) == 255);
PORT_Memcpy(ss->ssl3.hs.certReqContext, context.data, context.len);
ss->ssl3.hs.certReqContextLen = context.len;
rv = ssl3_ConsumeHandshakeVariable(ss, &algorithms, 2, &b, &length);
if (rv != SECSuccess)
return SECFailure;
if (algorithms.len == 0 || (algorithms.len & 1) != 0) {
FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_CERT_REQUEST,
illegal_parameter);
return SECFailure;
}
arena = ca_list.arena = PORT_NewArena(DER_DEFAULT_CHUNKSIZE);
if (!arena) {
FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
return SECFailure;
}
rv = ssl3_ParseCertificateRequestCAs(ss, &b, &length, arena, &ca_list);
if (rv != SECSuccess)
goto loser; /* alert sent below */
/* Verify that the extensions length is correct. */
extensionsLength = ssl3_ConsumeHandshakeNumber(ss, 2, &b, &length);
if (extensionsLength < 0) {
goto loser; /* alert sent below */
}
if (extensionsLength != length) {
FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_CERT_REQUEST,
illegal_parameter);
goto loser;
}
TLS13_SET_HS_STATE(ss, wait_server_cert);
rv = ssl3_CompleteHandleCertificateRequest(ss, &algorithms, &ca_list);
if (rv != SECSuccess) {
FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
goto loser;
}
return SECSuccess;
loser:
PORT_FreeArena(arena, PR_FALSE);
return SECFailure;
}
static SECStatus
tls13_InitializeHandshakeEncryption(sslSocket *ss)
{
SECStatus rv;
/* For all present cipher suites, SS = ES.
* TODO(ekr@rtfm.com): Revisit for 0-RTT. */
ss->ssl3.hs.xSS = PK11_ReferenceSymKey(ss->ssl3.hs.xES);
if (!ss->ssl3.hs.xSS) {
FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
return SECFailure;
}
rv = tls13_InitCipherSpec(ss, TrafficKeyHandshake,
InstallCipherSpecBoth);
if (rv != SECSuccess) {
FATAL_ERROR(ss, SSL_ERROR_INIT_CIPHER_SUITE_FAILURE, internal_error);
return SECFailure;
}
return rv;
}
/* Called from: ssl3_HandleClientHello */
SECStatus
tls13_SendServerHelloSequence(sslSocket *ss)
{
SECStatus rv;
SSL3KEAType certIndex;
SSL_TRC(3, ("%d: TLS13[%d]: begin send server_hello sequence",
SSL_GETPID(), ss->fd));
PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
PORT_Assert(ss->opt.noLocks || ssl_HaveXmitBufLock(ss));
rv = ssl3_SendServerHello(ss);
if (rv != SECSuccess) {
return rv; /* err code is set. */
}
rv = tls13_InitializeHandshakeEncryption(ss);
if (rv != SECSuccess) {
return SECFailure; /* error code is set. */
}
rv = tls13_SendEncryptedExtensions(ss);
if (rv != SECSuccess) {
return SECFailure; /* error code is set. */
}
if (ss->opt.requestCertificate) {
rv = tls13_SendCertificateRequest(ss);
if (rv != SECSuccess) {
return SECFailure; /* error code is set. */
}
}
rv = ssl3_SendCertificate(ss);
if (rv != SECSuccess) {
return SECFailure; /* error code is set. */
}
rv = ssl3_SendCertificateStatus(ss);
if (rv != SECSuccess) {
return SECFailure; /* error code is set. */
}
/* This was copied from: ssl3_SendCertificate.
* TODO(ekr@rtfm.com): Verify that this selection logic is correct.
* Bug 1237514.
*/
if ((ss->ssl3.hs.kea_def->kea == kea_ecdhe_rsa) ||
(ss->ssl3.hs.kea_def->kea == kea_dhe_rsa)) {
certIndex = kt_rsa;
} else {
certIndex = ss->ssl3.hs.kea_def->exchKeyType;
}
rv = ssl3_SendCertificateVerify(ss, ss->serverCerts[certIndex].SERVERKEY);
if (rv != SECSuccess) {
return rv; /* err code is set. */
}
/* Compute the rest of the secrets except for the resumption
* and exporter secret. */
rv = tls13_ComputeSecrets1(ss);
if (rv != SECSuccess) {
FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
return SECFailure;
}
rv = tls13_SendFinished(ss);
if (rv != SECSuccess) {
return rv; /* error code is set. */
}
TLS13_SET_HS_STATE(ss, ss->opt.requestCertificate ? wait_client_cert
: wait_finished);
return SECSuccess;
}
/*
* Called from ssl3_HandleServerHello.
*
* Caller must hold Handshake and RecvBuf locks.
*/
SECStatus
tls13_HandleServerKeyShare(sslSocket *ss)
{
SECStatus rv;
ECName expectedGroup;
PRCList *cur_p;
TLS13KeyShareEntry *entry;
SSL_TRC(3, ("%d: TLS13[%d]: handle server_key_share handshake",
SSL_GETPID(), ss->fd));
PORT_Assert(ss->opt.noLocks || ssl_HaveRecvBufLock(ss));
PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
switch (ss->ssl3.hs.kea_def->exchKeyType) {
#ifndef NSS_DISABLE_ECC
case ssl_kea_ecdh:
expectedGroup = ssl3_PubKey2ECName(ss->ephemeralECDHKeyPair->pubKey);
break;
#endif /* NSS_DISABLE_ECC */
default:
FATAL_ERROR(ss, SEC_ERROR_UNSUPPORTED_KEYALG, handshake_failure);
return SECFailure;
}
/* This list should have one entry. */
cur_p = PR_NEXT_LINK(&ss->ssl3.hs.remoteKeyShares);
if (!cur_p) {
FATAL_ERROR(ss, SSL_ERROR_MISSING_KEY_SHARE, missing_extension);
return SECFailure;
}
PORT_Assert(PR_NEXT_LINK(cur_p) == &ss->ssl3.hs.remoteKeyShares);
entry = (TLS13KeyShareEntry *)cur_p;
if (entry->group != expectedGroup) {
FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_KEY_SHARE, illegal_parameter);
return SECFailure;
}
rv = tls13_HandleECDHEKeyShare(ss, entry,
ss->ephemeralECDHKeyPair->privKey,
EphemeralSharedSecret);
ss->sec.keaType = ss->ssl3.hs.kea_def->exchKeyType;
ss->sec.keaKeyBits = SECKEY_PublicKeyStrengthInBits(
ss->ephemeralECDHKeyPair->pubKey);
if (rv != SECSuccess)
return SECFailure; /* Error code set below */
return tls13_InitializeHandshakeEncryption(ss);
}
/* Called from tls13_CompleteHandleHandshakeMessage() when it has deciphered a complete
* tls13 Certificate message.
* Caller must hold Handshake and RecvBuf locks.
*/
static SECStatus
tls13_HandleCertificate(sslSocket *ss, SSL3Opaque *b, PRUint32 length)
{
SECStatus rv;
SECItem context = { siBuffer, NULL, 0 };
SSL_TRC(3, ("%d: TLS13[%d]: handle certificate handshake",
SSL_GETPID(), ss->fd));
PORT_Assert(ss->opt.noLocks || ssl_HaveRecvBufLock(ss));
PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
if (ss->sec.isServer) {
rv = TLS13_CHECK_HS_STATE(ss, SSL_ERROR_RX_UNEXPECTED_CERTIFICATE,
wait_client_cert);
} else {
rv = TLS13_CHECK_HS_STATE(ss, SSL_ERROR_RX_UNEXPECTED_CERTIFICATE,
wait_cert_request, wait_server_cert);
}
if (rv != SECSuccess)
return SECFailure;
/* Process the context string */
rv = ssl3_ConsumeHandshakeVariable(ss, &context, 1, &b, &length);
if (rv != SECSuccess)
return SECFailure;
if (!ss->sec.isServer) {
if (context.len) {
/* The server's context string MUST be empty */
FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_CERTIFICATE,
illegal_parameter);
return SECFailure;
}
} else {
if (!context.len || context.len != ss->ssl3.hs.certReqContextLen ||
(NSS_SecureMemcmp(ss->ssl3.hs.certReqContext,
context.data, context.len) != 0)) {
FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_CERTIFICATE,
illegal_parameter);
return SECFailure;
}
context.len = 0; /* Belt and suspenders. Zero out the context. */
}
return ssl3_CompleteHandleCertificate(ss, b, length);
}
/* Called from tls13_CompleteHandleHandshakeMessage() when it has deciphered a complete
* ssl3 CertificateStatus message.
* Caller must hold Handshake and RecvBuf locks.
*/
static SECStatus
tls13_HandleCertificateStatus(sslSocket *ss, SSL3Opaque *b, PRUint32 length)
{
SECStatus rv;
rv = TLS13_CHECK_HS_STATE(ss, SSL_ERROR_RX_UNEXPECTED_CERT_STATUS,
wait_certificate_status);
if (rv != SECSuccess)
return rv;
return ssl3_CompleteHandleCertificateStatus(ss, b, length);
}
/*
* TODO(ekr@rtfm.com): This install logic needs renaming since it's
* what happens at various stages of cipher spec setup. Legacy from ssl3con.c.
*/
int
tls13_InstallCipherSpec(sslSocket *ss, InstallCipherSpecDirection direction)
{
SSL_TRC(3, ("%d: TLS13[%d]: Installing new cipher specs direction = %s",
SSL_GETPID(), ss->fd,
direction == InstallCipherSpecRead ? "read" : "write"));
PORT_Assert(!IS_DTLS(ss)); /* TODO(ekr@rtfm.com): Update for DTLS */
/* TODO(ekr@rtfm.com): Holddown timer for DTLS. */
ssl_GetSpecWriteLock(ss); /**************************************/
/* Flush out any old stuff in the handshake buffers */
switch (direction) {
case InstallCipherSpecWrite: {
ssl3CipherSpec *pwSpec;
pwSpec = ss->ssl3.pwSpec;
ss->ssl3.pwSpec = ss->ssl3.cwSpec;
ss->ssl3.cwSpec = pwSpec;
break;
} break;
case InstallCipherSpecRead: {
ssl3CipherSpec *prSpec;
prSpec = ss->ssl3.prSpec;
ss->ssl3.prSpec = ss->ssl3.crSpec;
ss->ssl3.crSpec = prSpec;
} break;
default:
PORT_Assert(0);
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
ssl_ReleaseSpecWriteLock(ss); /**************************************/
return SECFailure;
}
/* If we are really through with the old cipher prSpec
* (Both the read and write sides have changed) destroy it.
*/
if (ss->ssl3.prSpec == ss->ssl3.pwSpec) {
ssl3_DestroyCipherSpec(ss->ssl3.prSpec, PR_FALSE /*freeSrvName*/);
}
ssl_ReleaseSpecWriteLock(ss); /**************************************/
return SECSuccess;
}
/* Add context to the hash functions as described in
[draft-ietf-tls-tls13; Section 4.9.1] */
SECStatus
tls13_AddContextToHashes(sslSocket *ss, SSL3Hashes *hashes /* IN/OUT */,
SSLHashType algorithm, PRBool sending)
{
SECStatus rv = SECSuccess;
PK11Context *ctx;
const unsigned char context_padding[] = {
0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
};
const char *client_cert_verify_string = "TLS 1.3, client CertificateVerify";
const char *server_cert_verify_string = "TLS 1.3, server CertificateVerify";
const char *context_string = (sending ^ ss->sec.isServer) ? client_cert_verify_string
: server_cert_verify_string;
unsigned int hashlength;
/* Double check that we are doing SHA-256 for the handshake hash.*/
PORT_Assert(hashes->hashAlg == ssl_hash_sha256);
if (hashes->hashAlg != ssl_hash_sha256) {
PORT_SetError(SEC_ERROR_INVALID_ARGS);
goto loser;
}
PORT_Assert(hashes->len == 32);
ctx = PK11_CreateDigestContext(ssl3_TLSHashAlgorithmToOID(algorithm));
if (!ctx) {
PORT_SetError(SEC_ERROR_NO_MEMORY);
goto loser;
}
PORT_Assert(SECFailure);
PORT_Assert(!SECSuccess);
rv |= PK11_DigestBegin(ctx);
rv |= PK11_DigestOp(ctx, context_padding, sizeof(context_padding));
rv |= PK11_DigestOp(ctx, (unsigned char *)context_string,
strlen(context_string) + 1); /* +1 includes the terminating 0 */
rv |= PK11_DigestOp(ctx, hashes->u.raw, hashes->len);
/* Update the hash in-place */
rv |= PK11_DigestFinal(ctx, hashes->u.raw, &hashlength, sizeof(hashes->u.raw));
PK11_DestroyContext(ctx, PR_TRUE);
PRINT_BUF(90, (NULL, "TLS 1.3 hash with context", hashes->u.raw, hashlength));
hashes->len = hashlength;
hashes->hashAlg = algorithm;
if (rv) {
ssl_MapLowLevelError(SSL_ERROR_SHA_DIGEST_FAILURE);
goto loser;
}
return SECSuccess;
loser:
return SECFailure;
}
static SECStatus
tls13_HkdfExtractSharedKey(sslSocket *ss, PK11SymKey *key,
SharedSecretType keyType)
{
PK11SymKey **destp;
switch (keyType) {
case EphemeralSharedSecret:
destp = &ss->ssl3.hs.xES;
break;
case StaticSharedSecret:
destp = &ss->ssl3.hs.xSS;
break;
default:
PORT_Assert(0);
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
PORT_Assert(!*destp);
return tls13_HkdfExtract(NULL, key, tls13_GetHash(ss), destp);
}
static SECStatus
tls13_DeriveTrafficKeys(sslSocket *ss, ssl3CipherSpec *pwSpec,
TrafficKeyType type)
{
size_t keySize = pwSpec->cipher_def->key_size;
size_t ivSize = pwSpec->cipher_def->iv_size +
pwSpec->cipher_def->explicit_nonce_size; /* This isn't always going to
* work, but it does for
* AES-GCM */
CK_MECHANISM_TYPE bulkAlgorithm = ssl3_Alg2Mech(pwSpec->cipher_def->calg);
SSL3Hashes hashes;
PK11SymKey *prk = NULL;
const char *phase;
char label[256]; /* Arbitrary buffer large enough to hold the label */
SECStatus rv;
#define FORMAT_LABEL(phase_, purpose_) \
do { \
PRUint32 n = PR_snprintf(label, sizeof(label), "%s, %s", phase_, purpose_); \
/* Check for getting close. */ \
if ((n + 1) >= sizeof(label)) { \
PORT_Assert(0); \
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE); \
goto loser; \
} \
} while (0)
#define EXPAND_TRAFFIC_KEY(purpose_, target_) \
do { \
FORMAT_LABEL(phase, purpose_); \
rv = tls13_HkdfExpandLabel(prk, tls13_GetHash(ss), \
hashes.u.raw, hashes.len, \
label, strlen(label), \
bulkAlgorithm, keySize, &pwSpec->target_); \
if (rv != SECSuccess) { \
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE); \
PORT_Assert(0); \
goto loser; \
} \
} while (0)
#define EXPAND_TRAFFIC_IV(purpose_, target_) \
do { \
FORMAT_LABEL(phase, purpose_); \
rv = tls13_HkdfExpandLabelRaw(prk, tls13_GetHash(ss), \
hashes.u.raw, hashes.len, \
label, strlen(label), \
pwSpec->target_, ivSize); \
if (rv != SECSuccess) { \
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE); \
PORT_Assert(0); \
goto loser; \
} \
} while (0)
PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
PORT_Assert(ss->opt.noLocks || ssl_HaveSpecWriteLock(ss));
PORT_Assert(ss->ssl3.prSpec == ss->ssl3.pwSpec);
rv = ssl3_ComputeHandshakeHashes(ss, pwSpec, &hashes, 0);
if (rv != SECSuccess) {
PORT_Assert(0); /* Should never fail */
ssl_MapLowLevelError(SSL_ERROR_SESSION_KEY_GEN_FAILURE);
return SECFailure;
}
PRINT_BUF(60, (ss, "Deriving traffic keys. Session hash=", hashes.u.raw,
hashes.len));
switch (type) {
case TrafficKeyHandshake:
phase = kHkdfPhaseHandshakeKeys;
prk = ss->ssl3.hs.xES;
break;
case TrafficKeyApplicationData:
phase = kHkdfPhaseApplicationDataKeys;
prk = ss->ssl3.hs.trafficSecret;
break;
default:
PORT_Assert(0);
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
PORT_Assert(prk != NULL);
SSL_TRC(3, ("%d: TLS13[%d]: deriving traffic keys phase='%s'",
SSL_GETPID(), ss->fd, phase));
EXPAND_TRAFFIC_KEY(kHkdfPurposeClientWriteKey, client.write_key);
EXPAND_TRAFFIC_KEY(kHkdfPurposeServerWriteKey, server.write_key);
EXPAND_TRAFFIC_IV(kHkdfPurposeClientWriteIv, client.write_iv);
EXPAND_TRAFFIC_IV(kHkdfPurposeServerWriteIv, server.write_iv);
return SECSuccess;
loser:
return SECFailure;
}
/* Set up a cipher spec with keys. If install is nonzero, then also install
* it as the current cipher spec for each value in the mask. */
SECStatus
tls13_InitCipherSpec(sslSocket *ss, TrafficKeyType type, InstallCipherSpecDirection install)
{
ssl3CipherSpec *pwSpec;
ssl3CipherSpec *cwSpec;
SECStatus rv;
PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
if (install == InstallCipherSpecWrite ||
install == InstallCipherSpecBoth) {
ssl_GetXmitBufLock(ss);
rv = ssl3_FlushHandshake(ss, ssl_SEND_FLAG_FORCE_INTO_BUFFER);
ssl_ReleaseXmitBufLock(ss);
if (rv != SECSuccess) {
goto loser;
}
}
ssl_GetSpecWriteLock(ss); /**************************************/
PORT_Assert(ss->ssl3.prSpec == ss->ssl3.pwSpec);
pwSpec = ss->ssl3.pwSpec;
cwSpec = ss->ssl3.cwSpec;
switch (pwSpec->cipher_def->calg) {
case calg_aes_gcm:
pwSpec->aead = tls13_AESGCM;
break;
default:
PORT_Assert(0);
goto loser;
break;
}
/* Generic behaviors -- common to all crypto methods */
if (!IS_DTLS(ss)) {
pwSpec->read_seq_num.high = pwSpec->write_seq_num.high = 0;
} else {
if (cwSpec->epoch == PR_UINT16_MAX) {
/* The problem here is that we have rehandshaked too many
* times (you are not allowed to wrap the epoch). The
* spec says you should be discarding the connection
* and start over, so not much we can do here. */
rv = SECFailure;
goto loser;
}
/* The sequence number has the high 16 bits as the epoch. */
pwSpec->epoch = cwSpec->epoch + 1;
pwSpec->read_seq_num.high = pwSpec->write_seq_num.high =
pwSpec->epoch << 16;
dtls_InitRecvdRecords(&pwSpec->recvdRecords);
}
pwSpec->read_seq_num.low = pwSpec->write_seq_num.low = 0;
rv = tls13_DeriveTrafficKeys(ss, pwSpec, type);
if (rv != SECSuccess) {
goto loser;
}
if (install == InstallCipherSpecWrite ||
install == InstallCipherSpecBoth) {
rv = tls13_InstallCipherSpec(ss, InstallCipherSpecWrite);
if (rv != SECSuccess) {
goto loser;
}
}
if (install == InstallCipherSpecRead ||
install == InstallCipherSpecBoth) {
rv = tls13_InstallCipherSpec(ss, InstallCipherSpecRead);
if (rv != SECSuccess) {
goto loser;
}
}
ssl_ReleaseSpecWriteLock(ss); /**************************************/
return SECSuccess;
loser:
ssl_ReleaseSpecWriteLock(ss); /**************************************/
PORT_SetError(SSL_ERROR_INIT_CIPHER_SUITE_FAILURE);
return SECFailure;
}
static SECStatus
tls13_ComputeSecrets1(sslSocket *ss)
{
SECStatus rv;
PK11SymKey *mSS = NULL;
PK11SymKey *mES = NULL;
PK11SymKey *masterSecret = NULL;
SSL3Hashes hashes;
rv = ssl3_SetupPendingCipherSpec(ss);
if (rv != SECSuccess) {
return rv; /* error code set below. */
}
rv = ssl3_ComputeHandshakeHashes(ss, ss->ssl3.pwSpec, &hashes, 0);
if (rv != SECSuccess) {
PORT_Assert(0); /* Should never fail */
ssl_MapLowLevelError(SSL_ERROR_SESSION_KEY_GEN_FAILURE);
return SECFailure;
}
PORT_Assert(ss->ssl3.hs.xSS);
PORT_Assert(ss->ssl3.hs.xES);
rv = tls13_HkdfExpandLabel(ss->ssl3.hs.xSS,
tls13_GetHash(ss),
hashes.u.raw, hashes.len,
kHkdfLabelExpandedSs,
strlen(kHkdfLabelExpandedSs),
tls13_GetHkdfMechanism(ss),
hashes.len, &mSS);
if (rv != SECSuccess) {
goto loser;
}
rv = tls13_HkdfExpandLabel(ss->ssl3.hs.xES,
tls13_GetHash(ss),
hashes.u.raw, hashes.len,
kHkdfLabelExpandedEs,
strlen(kHkdfLabelExpandedEs),
tls13_GetHkdfMechanism(ss),
hashes.len, &mES);
if (rv != SECSuccess) {
goto loser;
}
rv = tls13_HkdfExtract(mSS, mES,
tls13_GetHash(ss),
&masterSecret);
if (rv != SECSuccess) {
goto loser;
}
rv = tls13_HkdfExpandLabel(masterSecret,
tls13_GetHash(ss),
hashes.u.raw, hashes.len,
kHkdfLabelTrafficSecret,
strlen(kHkdfLabelTrafficSecret),
tls13_GetHkdfMechanism(ss),
hashes.len, &ss->ssl3.hs.trafficSecret);
if (rv != SECSuccess) {
goto loser;
}
rv = tls13_HkdfExpandLabel(masterSecret,
tls13_GetHash(ss),
NULL, 0,
kHkdfLabelClientFinishedSecret,
strlen(kHkdfLabelClientFinishedSecret),
tls13_GetHmacMechanism(ss),
hashes.len, &ss->ssl3.hs.clientFinishedSecret);
if (rv != SECSuccess) {
goto loser;
}
rv = tls13_HkdfExpandLabel(masterSecret,
tls13_GetHash(ss),
NULL, 0,
kHkdfLabelServerFinishedSecret,
strlen(kHkdfLabelServerFinishedSecret),
tls13_GetHmacMechanism(ss),
hashes.len, &ss->ssl3.hs.serverFinishedSecret);
if (rv != SECSuccess) {
goto loser;
}
loser:
PK11_FreeSymKey(ss->ssl3.hs.xSS);
ss->ssl3.hs.xSS = NULL;
PK11_FreeSymKey(ss->ssl3.hs.xES);
ss->ssl3.hs.xES = NULL;
if (mSS) {
PK11_FreeSymKey(mSS);
}
if (mES) {
PK11_FreeSymKey(mES);
}
if (masterSecret) {
PK11_FreeSymKey(masterSecret);
}
return rv;
}
void
tls13_DestroyKeyShareEntry(TLS13KeyShareEntry *offer)
{
SECITEM_ZfreeItem(&offer->key_exchange, PR_FALSE);
PORT_ZFree(offer, sizeof(*offer));
}
void
tls13_DestroyKeyShares(PRCList *list)
{
PRCList *cur_p;
while (!PR_CLIST_IS_EMPTY(list)) {
cur_p = PR_LIST_TAIL(list);
PR_REMOVE_LINK(cur_p);
tls13_DestroyKeyShareEntry((TLS13KeyShareEntry *)cur_p);
}
}
/* Implement the SSLAEADCipher interface defined in sslimpl.h.
*
* That interface mixes the AD and the sequence number, but in
* TLS 1.3 there is no additional data so this value is just the
* encoded sequence number and we call it |seqNumBuf|.
*/
static SECStatus
tls13_AESGCM(ssl3KeyMaterial *keys,
PRBool doDecrypt,
unsigned char *out,
int *outlen,
int maxout,
const unsigned char *in,
int inlen,
const unsigned char *seqNumBuf,
int seqNumLen)
{
SECItem param;
SECStatus rv = SECFailure;
unsigned char nonce[12];
size_t i;
unsigned int uOutLen;
CK_GCM_PARAMS gcmParams;
static const int tagSize = 16;
PORT_Assert(seqNumLen == 8);
/* draft-ietf-tls-tls13 Section 5.2.2 specifies the following
* nonce algorithm:
*
* The length of the per-record nonce (iv_length) is set to max(8 bytes,
* N_MIN) for the AEAD algorithm (see [RFC5116] Section 4). An AEAD
* algorithm where N_MAX is less than 8 bytes MUST NOT be used with TLS.
* The per-record nonce for the AEAD construction is formed as follows:
*
* 1. The 64-bit record sequence number is padded to the left with
* zeroes to iv_length.
*
* 2. The padded sequence number is XORed with the static
* client_write_iv or server_write_iv, depending on the role.
*
* The resulting quantity (of length iv_length) is used as the per-
* record nonce.
*
* Per RFC 5288: N_MIN = N_MAX = 12 bytes.
*
*/
memcpy(nonce, keys->write_iv, sizeof(nonce));
for (i = 0; i < 8; ++i) {
nonce[4 + i] ^= seqNumBuf[i];
}
param.type = siBuffer;
param.data = (unsigned char *)&gcmParams;
param.len = sizeof(gcmParams);
gcmParams.pIv = nonce;
gcmParams.ulIvLen = sizeof(nonce);
gcmParams.pAAD = NULL;
gcmParams.ulAADLen = 0;
gcmParams.ulTagBits = tagSize * 8;
if (doDecrypt) {
rv = PK11_Decrypt(keys->write_key, CKM_AES_GCM, &param, out, &uOutLen,
maxout, in, inlen);
} else {
rv = PK11_Encrypt(keys->write_key, CKM_AES_GCM, &param, out, &uOutLen,
maxout, in, inlen);
}
*outlen = (int)uOutLen;
return rv;
}
static SECStatus
tls13_HandleEncryptedExtensions(sslSocket *ss, SSL3Opaque *b, PRUint32 length)
{
SECStatus rv;
PRInt32 innerLength;
PORT_Assert(ss->opt.noLocks || ssl_HaveRecvBufLock(ss));
PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
SSL_TRC(3, ("%d: TLS13[%d]: handle encrypted extensions",
SSL_GETPID(), ss->fd));
rv = TLS13_CHECK_HS_STATE(ss, SSL_ERROR_RX_UNEXPECTED_ENCRYPTED_EXTENSIONS,
wait_encrypted_extensions);
if (rv != SECSuccess) {
return SECFailure;
}
innerLength = ssl3_ConsumeHandshakeNumber(ss, 2, &b, &length);
if (innerLength < 0) {
return SECFailure; /* Alert already sent. */
}
if (innerLength != length) {
FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_ENCRYPTED_EXTENSIONS,
illegal_parameter);
return SECFailure;
}
rv = ssl3_HandleHelloExtensions(ss, &b, &length, encrypted_extensions);
if (rv != SECSuccess) {
return SECFailure; /* Error code set below */
}
TLS13_SET_HS_STATE(ss, wait_cert_request);
return SECSuccess;
}
static SECStatus
tls13_SendEncryptedExtensions(sslSocket *ss)
{
SECStatus rv;
PRInt32 extensions_len = 0;
PRInt32 sent_len = 0;
PRUint32 maxBytes = 65535;
SSL_TRC(3, ("%d: TLS13[%d]: send encrypted extensions handshake",
SSL_GETPID(), ss->fd));
PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
PORT_Assert(ss->opt.noLocks || ssl_HaveXmitBufLock(ss));
extensions_len = ssl3_CallHelloExtensionSenders(
ss, PR_FALSE, maxBytes, &ss->xtnData.encryptedExtensionsSenders[0]);
rv = ssl3_AppendHandshakeHeader(ss, encrypted_extensions,
extensions_len + 2);
if (rv != SECSuccess) {
FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
return SECFailure;
}
rv = ssl3_AppendHandshakeNumber(ss, extensions_len, 2);
if (rv != SECSuccess) {
FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
return SECFailure;
}
sent_len = ssl3_CallHelloExtensionSenders(
ss, PR_TRUE, extensions_len,
&ss->xtnData.encryptedExtensionsSenders[0]);
PORT_Assert(sent_len == extensions_len);
if (sent_len != extensions_len) {
PORT_Assert(sent_len == 0);
FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
return SECFailure;
}
return SECSuccess;
}
/* Called from tls13_CompleteHandleHandshakeMessage() when it has deciphered a complete
* tls13 CertificateVerify message
* Caller must hold Handshake and RecvBuf locks.
*/
SECStatus
tls13_HandleCertificateVerify(sslSocket *ss, SSL3Opaque *b, PRUint32 length,
SSL3Hashes *hashes)
{
SECItem signed_hash = { siBuffer, NULL, 0 };
SECStatus rv;
SSLSignatureAndHashAlg sigAndHash;
SSL_TRC(3, ("%d: TLS13[%d]: handle certificate_verify handshake",
SSL_GETPID(), ss->fd));
PORT_Assert(ss->opt.noLocks || ssl_HaveRecvBufLock(ss));
PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
rv = TLS13_CHECK_HS_STATE(ss, SSL_ERROR_RX_UNEXPECTED_CERT_VERIFY,
wait_cert_verify);
if (rv != SECSuccess) {
return SECFailure;
}
if (!hashes) {
FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
return SECFailure;
}
/* We only support CertificateVerify messages that use the handshake
* hash.
* TODO(ekr@rtfm.com): This should be easy to relax in TLS 1.3 by
* reading the client's hash algorithm first, but there may
* be subtleties so retain the restriction for now.
*/
rv = tls13_AddContextToHashes(ss, hashes, hashes->hashAlg, PR_FALSE);
if (rv != SECSuccess) {
FATAL_ERROR(ss, SSL_ERROR_DIGEST_FAILURE, internal_error);
return SECFailure;
}
rv = ssl3_ConsumeSignatureAndHashAlgorithm(ss, &b, &length,
&sigAndHash);
if (rv != SECSuccess) {
PORT_SetError(SSL_ERROR_RX_MALFORMED_CERT_VERIFY);
return SECFailure;
}
rv = ssl3_CheckSignatureAndHashAlgorithmConsistency(
ss, &sigAndHash, ss->sec.peerCert);
if (rv != SECSuccess) {
FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_CERT_VERIFY, decrypt_error);
return SECFailure;
}
/* We only support CertificateVerify messages that use the handshake
* hash. */
if (sigAndHash.hashAlg != hashes->hashAlg) {
FATAL_ERROR(ss, SSL_ERROR_UNSUPPORTED_HASH_ALGORITHM, decrypt_error);
return SECFailure;
}
rv = ssl3_ConsumeHandshakeVariable(ss, &signed_hash, 2, &b, &length);
if (rv != SECSuccess) {
PORT_SetError(SSL_ERROR_RX_MALFORMED_CERT_VERIFY);
return SECFailure;
}
if (length != 0) {
FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_CERT_VERIFY, decode_error);
return SECFailure;
}
rv = ssl3_VerifySignedHashes(hashes, ss->sec.peerCert, &signed_hash,
PR_TRUE, ss->pkcs11PinArg);
if (rv != SECSuccess) {
FATAL_ERROR(ss, PORT_GetError(), decrypt_error);
return SECFailure;
}
if (!ss->sec.isServer) {
/* Compute the rest of the secrets except for the resumption
* and exporter secret. */
rv = tls13_ComputeSecrets1(ss);
if (rv != SECSuccess) {
FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
return SECFailure;
}
}
TLS13_SET_HS_STATE(ss, wait_finished);
return SECSuccess;
}
static SECStatus
tls13_ComputeFinished(sslSocket *ss, const SSL3Hashes *hashes, PRBool sending,
PRUint8 *output, unsigned int *outputLen, unsigned int maxOutputLen)
{
SECStatus rv;
PK11Context *hmacCtx = NULL;
CK_MECHANISM_TYPE macAlg = tls13_GetHmacMechanism(ss);
SECItem param = { siBuffer, NULL, 0 };
unsigned int outputLenUint;
PK11SymKey *secret = (ss->sec.isServer ^ sending) ? ss->ssl3.hs.clientFinishedSecret
: ss->ssl3.hs.serverFinishedSecret;
PORT_Assert(secret);
PRINT_BUF(90, (NULL, "Handshake hash", hashes->u.raw, hashes->len));
hmacCtx = PK11_CreateContextBySymKey(macAlg, CKA_SIGN,
secret, &param);
if (!hmacCtx) {
goto abort;
}
rv = PK11_DigestBegin(hmacCtx);
if (rv != SECSuccess)
goto abort;
rv = PK11_DigestOp(hmacCtx, hashes->u.raw, hashes->len);
if (rv != SECSuccess)
goto abort;
PORT_Assert(maxOutputLen >= hashes->len);
rv = PK11_DigestFinal(hmacCtx, output, &outputLenUint, maxOutputLen);
if (rv != SECSuccess)
goto abort;
*outputLen = outputLenUint;
PK11_DestroyContext(hmacCtx, PR_TRUE);
return SECSuccess;
abort:
if (hmacCtx) {
PK11_DestroyContext(hmacCtx, PR_TRUE);
}
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
static SECStatus
tls13_SendFinished(sslSocket *ss)
{
SECStatus rv;
PRUint8 finishedBuf[MAX_FINISHED_SIZE];
unsigned int finishedLen;
SSL3Hashes hashes;
int errCode;
SSL_TRC(3, ("%d: TLS13[%d]: send finished handshake", SSL_GETPID(), ss->fd));
PORT_Assert(ss->opt.noLocks || ssl_HaveXmitBufLock(ss));
PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
rv = ssl3_ComputeHandshakeHashes(ss, ss->ssl3.cwSpec, &hashes, 0);
if (rv != SECSuccess) {
FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
return SECFailure;
}
ssl_GetSpecReadLock(ss);
rv = tls13_ComputeFinished(ss, &hashes, PR_TRUE,
finishedBuf, &finishedLen, sizeof(finishedBuf));
ssl_ReleaseSpecReadLock(ss);
if (rv != SECSuccess) {
FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
return SECFailure;
}
rv = ssl3_AppendHandshakeHeader(ss, finished, finishedLen);
if (rv != SECSuccess) {
errCode = PR_GetError();
goto alert_loser;
}
rv = ssl3_AppendHandshake(ss, finishedBuf, finishedLen);
if (rv != SECSuccess) {
errCode = PR_GetError();
goto alert_loser;
}
rv = ssl3_FlushHandshake(ss, 0);
if (rv != SECSuccess) {
errCode = PR_GetError();
goto alert_loser;
}
if (ss->sec.isServer) {
rv = tls13_InitCipherSpec(ss, TrafficKeyApplicationData,
InstallCipherSpecWrite);
} else {
rv = tls13_InstallCipherSpec(ss, InstallCipherSpecWrite);
}
if (rv != SECSuccess) {
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
/* TODO(ekr@rtfm.com): Record key log */
return SECSuccess;
alert_loser:
(void)SSL3_SendAlert(ss, alert_fatal, internal_error);
PORT_SetError(errCode); /* Restore error code */
return rv;
}
static SECStatus
tls13_HandleFinished(sslSocket *ss, SSL3Opaque *b, PRUint32 length,
const SSL3Hashes *hashes)
{
SECStatus rv;
PRUint8 finishedBuf[MAX_FINISHED_SIZE];
unsigned int finishedLen;
PORT_Assert(ss->opt.noLocks || ssl_HaveRecvBufLock(ss));
PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
SSL_TRC(3, ("%d: TLS13[%d]: handle finished handshake",
SSL_GETPID(), ss->fd));
rv = TLS13_CHECK_HS_STATE(ss, SSL_ERROR_RX_UNEXPECTED_FINISHED, wait_finished);
if (rv != SECSuccess) {
return SECFailure;
}
if (!hashes) {
FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
return SECFailure;
}
ssl_GetSpecReadLock(ss);
rv = tls13_ComputeFinished(ss, hashes, PR_FALSE,
finishedBuf, &finishedLen, sizeof(finishedBuf));
ssl_ReleaseSpecReadLock(ss);
if (rv != SECSuccess) {
FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
return SECFailure;
}
if (length != finishedLen) {
FATAL_ERROR(ss, SSL_ERROR_RX_MALFORMED_FINISHED, decode_error);
return SECFailure;
}
if (NSS_SecureMemcmp(b, finishedBuf, finishedLen) != 0) {
FATAL_ERROR(ss, SSL_ERROR_BAD_HANDSHAKE_HASH_VALUE,
decrypt_error);
return SECFailure;
}
/* Server is now finished.
* Client sends second flight
*/
/* TODO(ekr@rtfm.com): Send NewSession Ticket if server. */
if (ss->sec.isServer) {
rv = tls13_InstallCipherSpec(ss, InstallCipherSpecRead);
if (rv != SECSuccess) {
FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
return SECFailure;
}
rv = tls13_FinishHandshake(ss);
} else {
if (ss->ssl3.hs.authCertificatePending) {
/* TODO(ekr@rtfm.com): Handle pending auth */
FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
PORT_Assert(0);
return SECFailure;
}
rv = tls13_InitCipherSpec(ss, TrafficKeyApplicationData,
InstallCipherSpecRead);
if (rv != SECSuccess) {
FATAL_ERROR(ss, SEC_ERROR_LIBRARY_FAILURE, internal_error);
return SECFailure;
}
rv = tls13_SendClientSecondRound(ss);
if (rv != SECSuccess)
return SECFailure; /* Error code and alerts handled below */
}
return rv;
}
static SECStatus
tls13_FinishHandshake(sslSocket *ss)
{
PORT_Assert(ss->opt.noLocks || ssl_HaveRecvBufLock(ss));
PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
PORT_Assert(ss->ssl3.hs.restartTarget == NULL);
/* The first handshake is now completed. */
ss->handshake = NULL;
TLS13_SET_HS_STATE(ss, idle_handshake);
ssl_FinishHandshake(ss);
return SECSuccess;
}
static SECStatus
tls13_SendClientSecondRound(sslSocket *ss)
{
SECStatus rv;
PRBool sendClientCert;
PORT_Assert(ss->opt.noLocks || ssl_HaveRecvBufLock(ss));
PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss));
sendClientCert = !ss->ssl3.sendEmptyCert &&
ss->ssl3.clientCertChain != NULL &&
ss->ssl3.clientPrivateKey != NULL;
/* Defer client authentication sending if we are still
* waiting for server authentication. See the long block
* comment in ssl3_SendClientSecondRound for more detail.
*/
if (ss->ssl3.hs.restartTarget) {
PR_NOT_REACHED("unexpected ss->ssl3.hs.restartTarget");
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
if (ss->ssl3.hs.authCertificatePending && (sendClientCert ||
ss->ssl3.sendEmptyCert)) {
SSL_TRC(3, ("%d: TLS13[%p]: deferring ssl3_SendClientSecondRound because"
" certificate authentication is still pending.",
SSL_GETPID(), ss->fd));
ss->ssl3.hs.restartTarget = tls13_SendClientSecondRound;
return SECWouldBlock;
}
ssl_GetXmitBufLock(ss); /*******************************/
if (ss->ssl3.sendEmptyCert) {
ss->ssl3.sendEmptyCert = PR_FALSE;
rv = ssl3_SendEmptyCertificate(ss);
/* Don't send verify */
if (rv != SECSuccess) {
goto loser; /* error code is set. */
}
} else if (sendClientCert) {
rv = ssl3_SendCertificate(ss);
if (rv != SECSuccess) {
goto loser; /* error code is set. */
}
}
if (sendClientCert) {
rv = ssl3_SendCertificateVerify(ss, ss->ssl3.clientPrivateKey);
SECKEY_DestroyPrivateKey(ss->ssl3.clientPrivateKey);
ss->ssl3.clientPrivateKey = NULL;
if (rv != SECSuccess) {
goto loser; /* err is set. */
}
}
rv = tls13_SendFinished(ss);
if (rv != SECSuccess) {
goto loser; /* err code was set. */
}
ssl_ReleaseXmitBufLock(ss); /*******************************/
/* The handshake is now finished */
return tls13_FinishHandshake(ss);
loser:
ssl_ReleaseXmitBufLock(ss); /*******************************/
return SECFailure;
}
static SECStatus
tls13_HandleNewSessionTicket(sslSocket *ss, SSL3Opaque *b, PRUint32 length)
{
SECStatus rv;
rv = TLS13_CHECK_HS_STATE(ss, SSL_ERROR_RX_UNEXPECTED_NEW_SESSION_TICKET,
idle_handshake);
if (rv != SECSuccess) {
return SECFailure;
}
UNIMPLEMENTED();
/* Ignore */
return SECSuccess;
}
typedef enum {
ExtensionNotUsed,
ExtensionClientOnly,
ExtensionSendClear,
ExtensionSendEncrypted,
} Tls13ExtensionStatus;
static const struct {
SSLExtensionType ex_value;
Tls13ExtensionStatus status;
} KnownExtensions[] = {
{ ssl_server_name_xtn,
ExtensionSendEncrypted },
{
ssl_cert_status_xtn,
ExtensionNotUsed /* TODO(ekr@rtfm.com): Disabled because broken
in TLS 1.3. */
/* ExtensionSendEncrypted */
},
{ ssl_elliptic_curves_xtn,
ExtensionSendClear },
{ ssl_ec_point_formats_xtn,
ExtensionNotUsed },
{ ssl_signature_algorithms_xtn,
ExtensionClientOnly },
{ ssl_use_srtp_xtn,
ExtensionSendEncrypted },
{ ssl_app_layer_protocol_xtn,
ExtensionSendEncrypted },
{ ssl_padding_xtn,
ExtensionNotUsed },
{ ssl_extended_master_secret_xtn,
ExtensionNotUsed },
{ ssl_session_ticket_xtn,
ExtensionClientOnly },
{ ssl_tls13_key_share_xtn,
ExtensionSendClear },
{ ssl_next_proto_nego_xtn,
ExtensionNotUsed },
{ ssl_renegotiation_info_xtn,
ExtensionNotUsed },
{ ssl_tls13_draft_version_xtn,
ExtensionClientOnly }
};
PRBool
tls13_ExtensionAllowed(PRUint16 extension, SSL3HandshakeType message)
{
unsigned int i;
PORT_Assert((message == client_hello) ||
(message == server_hello) ||
(message == encrypted_extensions));
for (i = 0; i < PR_ARRAY_SIZE(KnownExtensions); i++) {
if (KnownExtensions[i].ex_value == extension)
break;
}
if (i == PR_ARRAY_SIZE(KnownExtensions)) {
/* We have never heard of this extension which is OK on
* the server but not the client. */
return message == client_hello;
}
switch (KnownExtensions[i].status) {
case ExtensionNotUsed:
return PR_FALSE;
case ExtensionClientOnly:
return message == client_hello;
case ExtensionSendClear:
return message == client_hello ||
message == server_hello;
case ExtensionSendEncrypted:
return message == client_hello ||
message == encrypted_extensions;
}
PORT_Assert(0);
/* Not reached */
return PR_TRUE;
}
/* Helper function to encode a uint32 into a buffer */
unsigned char *
tls13_EncodeUintX(PRUint32 value, unsigned int bytes, unsigned char *to)
{
PRUint32 encoded;
PORT_Assert(bytes > 0 && bytes <= 4);
encoded = PR_htonl(value);
memcpy(to, ((unsigned char *)(&encoded)) + (4 - bytes), bytes);
return to + bytes;
}
/* TLS 1.3 doesn't actually have additional data but the aead function
* signature overloads additional data to carry the record sequence
* number and that's what we put here. The TLS 1.3 AEAD functions
* just use this input as the sequence number and not as additional
* data. */
static void
tls13_FormatAdditionalData(unsigned char *aad, unsigned int length,
SSL3SequenceNumber seqNum)
{
unsigned char *ptr = aad;
PORT_Assert(length == 8);
ptr = tls13_EncodeUintX(seqNum.high, 4, ptr);
ptr = tls13_EncodeUintX(seqNum.low, 4, ptr);
PORT_Assert((ptr - aad) == length);
}
SECStatus
tls13_ProtectRecord(sslSocket *ss,
SSL3ContentType type,
const SSL3Opaque *pIn,
PRUint32 contentLen,
sslBuffer *wrBuf)
{
ssl3CipherSpec *cwSpec = ss->ssl3.cwSpec;
const ssl3BulkCipherDef *cipher_def = cwSpec->cipher_def;
SECStatus rv;
PRUint16 headerLen;
int cipherBytes = 0;
const int tagLen = cipher_def->tag_size;
SSL_TRC(3, ("%d: TLS13[%d]: protect record of length %u, seq=0x%0x%0x",
SSL_GETPID(), ss->fd, contentLen,
cwSpec->write_seq_num.high,
cwSpec->write_seq_num.low));
headerLen = IS_DTLS(ss) ? DTLS_RECORD_HEADER_LENGTH : SSL3_RECORD_HEADER_LENGTH;
if (headerLen + contentLen + 1 + tagLen > wrBuf->space) {
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
/* Copy the data into the wrBuf. We're going to encrypt in-place
* in the AEAD branch anyway */
PORT_Memcpy(wrBuf->buf + headerLen, pIn, contentLen);
if (cipher_def->calg == ssl_calg_null) {
/* Shortcut for plaintext */
cipherBytes = contentLen;
} else {
unsigned char aad[8];
PORT_Assert(cipher_def->type == type_aead);
/* Add the content type at the end. */
wrBuf->buf[headerLen + contentLen] = type;
/* Stomp the content type to be application_data */
type = content_application_data;
tls13_FormatAdditionalData(aad, sizeof(aad),
cwSpec->write_seq_num);
cipherBytes = contentLen + 1; /* Room for the content type on the end. */
rv = cwSpec->aead(
ss->sec.isServer ? &cwSpec->server : &cwSpec->client,
PR_FALSE, /* do encrypt */
wrBuf->buf + headerLen, /* output */
&cipherBytes, /* out len */
wrBuf->space - headerLen, /* max out */
wrBuf->buf + headerLen, contentLen + 1, /* input */
aad, sizeof(aad));
if (rv != SECSuccess) {
PORT_SetError(SSL_ERROR_ENCRYPTION_FAILURE);
return SECFailure;
}
}
PORT_Assert(cipherBytes <= MAX_FRAGMENT_LENGTH + 256);
wrBuf->len = cipherBytes + headerLen;
wrBuf->buf[0] = type;
if (IS_DTLS(ss)) {
(void)tls13_EncodeUintX(2, dtls_TLSVersionToDTLSVersion(kRecordVersion),
&wrBuf->buf[1]);
(void)tls13_EncodeUintX(cwSpec->write_seq_num.high, 4, &wrBuf->buf[3]);
(void)tls13_EncodeUintX(cwSpec->write_seq_num.low, 4, &wrBuf->buf[7]);
(void)tls13_EncodeUintX(cipherBytes, 2, &wrBuf->buf[11]);
} else {
(void)tls13_EncodeUintX(kRecordVersion, 2, &wrBuf->buf[1]);
(void)tls13_EncodeUintX(cipherBytes, 2, &wrBuf->buf[3]);
}
ssl3_BumpSequenceNumber(&cwSpec->write_seq_num);
return SECSuccess;
}
/* Unprotect a TLS 1.3 record and leave the result in plaintext.
*
* Called by ssl3_HandleRecord. Caller must hold the spec read lock.
* Therefore, we MUST not call SSL3_SendAlert().
*
* If SECFailure is returned, we:
* 1. Set |*alert| to the alert to be sent.
* 2. Call PORT_SetError() witn an appropriate code.
*/
SECStatus
tls13_UnprotectRecord(sslSocket *ss, SSL3Ciphertext *cText, sslBuffer *plaintext,
SSL3AlertDescription *alert)
{
ssl3CipherSpec *crSpec = ss->ssl3.crSpec;
const ssl3BulkCipherDef *cipher_def = crSpec->cipher_def;
unsigned char aad[8];
SECStatus rv;
*alert = bad_record_mac; /* Default alert for most issues. */
SSL_TRC(3, ("%d: TLS13[%d]: unprotect record of length %u",
SSL_GETPID(), ss->fd, cText->buf->len));
/* We can perform this test in variable time because the record's total
* length and the ciphersuite are both public knowledge. */
if (cText->buf->len < cipher_def->tag_size) {
PORT_SetError(SSL_ERROR_RX_RECORD_TOO_LONG);
return SECFailure;
}
/* Verify that the content type is right, even though we overwrite it. */
if (cText->type != content_application_data) {
/* Do we need a better error here? */
PORT_SetError(SSL_ERROR_BAD_MAC_READ);
return SECFailure;
}
/* Check the version number in the record */
if (cText->version != kRecordVersion) {
/* Do we need a better error here? */
PORT_SetError(SSL_ERROR_BAD_MAC_READ);
return SECFailure;
}
/* Decrypt */
PORT_Assert(cipher_def->type == type_aead);
tls13_FormatAdditionalData(aad, sizeof(aad),
IS_DTLS(ss) ? cText->seq_num
: crSpec->read_seq_num);
rv = crSpec->aead(
ss->sec.isServer ? &crSpec->client : &crSpec->server,
PR_TRUE, /* do decrypt */
plaintext->buf, /* out */
(int *)&plaintext->len, /* outlen */
plaintext->space, /* maxout */
cText->buf->buf, /* in */
cText->buf->len, /* inlen */
aad, sizeof(aad));
if (rv != SECSuccess) {
PORT_SetError(SSL_ERROR_BAD_MAC_READ);
return SECFailure;
}
/* The record is right-padded with 0s, followed by the true
* content type, so read from the right until we receive a
* nonzero byte. */
while (plaintext->len > 0 && !(plaintext->buf[plaintext->len - 1])) {
--plaintext->len;
}
/* Bogus padding. */
if (plaintext->len < 1) {
/* It's safe to report this specifically because it happened
* after the MAC has been verified. */
PORT_SetError(SSL_ERROR_BAD_BLOCK_PADDING);
return SECFailure;
}
/* Record the type. */
cText->type = plaintext->buf[plaintext->len - 1];
--plaintext->len;
return SECSuccess;
}