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/* 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 "blapi.h"
#include "ssl.h"
#include "sslimpl.h"
#include "tls_connect.h"
#include "gtest/gtest.h"
namespace nss_test {
#ifdef UNSAFE_FUZZER_MODE
const uint8_t kShortEmptyFinished[8] = {0};
const uint8_t kLongEmptyFinished[128] = {0};
class TlsFuzzTest : public ::testing::Test {};
// Record the application data stream.
class TlsApplicationDataRecorder : public TlsRecordFilter {
public:
TlsApplicationDataRecorder() : buffer_() {}
virtual PacketFilter::Action FilterRecord(const RecordHeader& header,
const DataBuffer& input,
DataBuffer* output) {
if (header.content_type() == kTlsApplicationDataType) {
buffer_.Append(input);
}
return KEEP;
}
const DataBuffer& buffer() const { return buffer_; }
private:
DataBuffer buffer_;
};
// Damages an SKE or CV signature.
class TlsSignatureDamager : public TlsHandshakeFilter {
public:
TlsSignatureDamager(uint8_t type) : type_(type) {}
virtual PacketFilter::Action FilterHandshake(
const TlsHandshakeFilter::HandshakeHeader& header,
const DataBuffer& input, DataBuffer* output) {
if (header.handshake_type() != type_) {
return KEEP;
}
*output = input;
// Modify the last byte of the signature.
output->data()[output->len() - 1]++;
return CHANGE;
}
private:
uint8_t type_;
};
void ResetState() {
// Clear the list of RSA blinding params.
BL_Cleanup();
// Reinit the list of RSA blinding params.
EXPECT_EQ(SECSuccess, BL_Init());
// Reset the RNG state.
EXPECT_EQ(SECSuccess, RNG_ResetForFuzzing());
}
// Ensure that ssl_Time() returns a constant value.
TEST_F(TlsFuzzTest, Fuzz_SSL_Time_Constant) {
PRInt32 now = ssl_Time();
PR_Sleep(PR_SecondsToInterval(2));
EXPECT_EQ(ssl_Time(), now);
}
// Check that due to the deterministic PRNG we derive
// the same master secret in two consecutive TLS sessions.
TEST_P(TlsConnectGeneric, Fuzz_DeterministicExporter) {
const char kLabel[] = "label";
std::vector<unsigned char> out1(32), out2(32);
ConfigureSessionCache(RESUME_NONE, RESUME_NONE);
DisableECDHEServerKeyReuse();
ResetState();
Connect();
// Export a key derived from the MS and nonces.
SECStatus rv =
SSL_ExportKeyingMaterial(client_->ssl_fd(), kLabel, strlen(kLabel), false,
NULL, 0, out1.data(), out1.size());
EXPECT_EQ(SECSuccess, rv);
Reset();
ConfigureSessionCache(RESUME_NONE, RESUME_NONE);
DisableECDHEServerKeyReuse();
ResetState();
Connect();
// Export another key derived from the MS and nonces.
rv = SSL_ExportKeyingMaterial(client_->ssl_fd(), kLabel, strlen(kLabel),
false, NULL, 0, out2.data(), out2.size());
EXPECT_EQ(SECSuccess, rv);
// The two exported keys should be the same.
EXPECT_EQ(out1, out2);
}
// Check that due to the deterministic RNG two consecutive
// TLS sessions will have the exact same transcript.
TEST_P(TlsConnectGeneric, Fuzz_DeterministicTranscript) {
// Connect a few times and compare the transcripts byte-by-byte.
DataBuffer last;
for (size_t i = 0; i < 5; i++) {
Reset();
ConfigureSessionCache(RESUME_NONE, RESUME_NONE);
DisableECDHEServerKeyReuse();
DataBuffer buffer;
client_->SetPacketFilter(new TlsConversationRecorder(buffer));
server_->SetPacketFilter(new TlsConversationRecorder(buffer));
ResetState();
Connect();
// Ensure the filters go away before |buffer| does.
client_->SetPacketFilter(nullptr);
server_->SetPacketFilter(nullptr);
if (last.len() > 0) {
EXPECT_EQ(last, buffer);
}
last = buffer;
}
}
// Check that we can establish and use a connection
// with all supported TLS versions, STREAM and DGRAM.
// Check that records are NOT encrypted.
// Check that records don't have a MAC.
TEST_P(TlsConnectGeneric, Fuzz_ConnectSendReceive_NullCipher) {
EnsureTlsSetup();
// Set up app data filters.
auto client_recorder = new TlsApplicationDataRecorder();
client_->SetPacketFilter(client_recorder);
auto server_recorder = new TlsApplicationDataRecorder();
server_->SetPacketFilter(server_recorder);
Connect();
// Construct the plaintext.
DataBuffer buf;
buf.Allocate(50);
for (size_t i = 0; i < buf.len(); ++i) {
buf.data()[i] = i & 0xff;
}
// Send/Receive data.
client_->SendBuffer(buf);
server_->SendBuffer(buf);
Receive(buf.len());
// Check for plaintext on the wire.
EXPECT_EQ(buf, client_recorder->buffer());
EXPECT_EQ(buf, server_recorder->buffer());
}
// Check that an invalid Finished message doesn't abort the connection.
TEST_P(TlsConnectGeneric, Fuzz_BogusClientFinished) {
EnsureTlsSetup();
auto i1 = new TlsInspectorReplaceHandshakeMessage(
kTlsHandshakeFinished,
DataBuffer(kShortEmptyFinished, sizeof(kShortEmptyFinished)));
client_->SetPacketFilter(i1);
Connect();
SendReceive();
}
// Check that an invalid Finished message doesn't abort the connection.
TEST_P(TlsConnectGeneric, Fuzz_BogusServerFinished) {
EnsureTlsSetup();
auto i1 = new TlsInspectorReplaceHandshakeMessage(
kTlsHandshakeFinished,
DataBuffer(kLongEmptyFinished, sizeof(kLongEmptyFinished)));
server_->SetPacketFilter(i1);
Connect();
SendReceive();
}
// Check that an invalid server auth signature doesn't abort the connection.
TEST_P(TlsConnectGeneric, Fuzz_BogusServerAuthSignature) {
EnsureTlsSetup();
uint8_t msg_type = version_ == SSL_LIBRARY_VERSION_TLS_1_3
? kTlsHandshakeCertificateVerify
: kTlsHandshakeServerKeyExchange;
server_->SetPacketFilter(new TlsSignatureDamager(msg_type));
Connect();
SendReceive();
}
// Check that an invalid client auth signature doesn't abort the connection.
TEST_P(TlsConnectGeneric, Fuzz_BogusClientAuthSignature) {
EnsureTlsSetup();
client_->SetupClientAuth();
server_->RequestClientAuth(true);
client_->SetPacketFilter(
new TlsSignatureDamager(kTlsHandshakeCertificateVerify));
Connect();
}
#endif
}
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