Make SimpleRandom faster by using Chacha20 as underlying primitive.
This does alter the output of the RNG, but that's a one-time cost, and one SHA-1 call per byte is highly suboptimal for anything but very short unit tests.
gfe-relnote: n/a (test-only change)
PiperOrigin-RevId: 245501012
Change-Id: I16d9f5b174ef65cfb4ece3ef0699bf1b29b81de5
diff --git a/quic/test_tools/quic_test_utils.cc b/quic/test_tools/quic_test_utils.cc
index cacb28a..52634b7 100644
--- a/quic/test_tools/quic_test_utils.cc
+++ b/quic/test_tools/quic_test_utils.cc
@@ -5,8 +5,10 @@
#include "net/third_party/quiche/src/quic/test_tools/quic_test_utils.h"
#include <algorithm>
+#include <cstdint>
#include <memory>
+#include "third_party/boringssl/src/include/openssl/chacha.h"
#include "third_party/boringssl/src/include/openssl/sha.h"
#include "net/third_party/quiche/src/quic/core/crypto/crypto_framer.h"
#include "net/third_party/quiche/src/quic/core/crypto/crypto_handshake.h"
@@ -152,20 +154,42 @@
}
uint64_t SimpleRandom::RandUint64() {
- std::string hash =
- Sha1Hash(QuicStringPiece(reinterpret_cast<char*>(&seed_), sizeof(seed_)));
- DCHECK_EQ(static_cast<size_t>(SHA_DIGEST_LENGTH), hash.length());
- memcpy(&seed_, hash.data(), sizeof(seed_));
- return seed_;
+ uint64_t result;
+ RandBytes(&result, sizeof(result));
+ return result;
}
void SimpleRandom::RandBytes(void* data, size_t len) {
- uint8_t* real_data = static_cast<uint8_t*>(data);
- for (size_t offset = 0; offset < len; offset++) {
- real_data[offset] = RandUint64() & 0xff;
+ uint8_t* data_bytes = reinterpret_cast<uint8_t*>(data);
+ while (len > 0) {
+ const size_t buffer_left = sizeof(buffer_) - buffer_offset_;
+ const size_t to_copy = std::min(buffer_left, len);
+ memcpy(data_bytes, buffer_ + buffer_offset_, to_copy);
+ data_bytes += to_copy;
+ buffer_offset_ += to_copy;
+ len -= to_copy;
+
+ if (buffer_offset_ == sizeof(buffer_)) {
+ FillBuffer();
+ }
}
}
+void SimpleRandom::FillBuffer() {
+ uint8_t nonce[12];
+ memcpy(nonce, buffer_, sizeof(nonce));
+ CRYPTO_chacha_20(buffer_, buffer_, sizeof(buffer_), key_, nonce, 0);
+ buffer_offset_ = 0;
+}
+
+void SimpleRandom::set_seed(uint64_t seed) {
+ static_assert(sizeof(key_) == SHA256_DIGEST_LENGTH, "Key has to be 256 bits");
+ SHA256(reinterpret_cast<const uint8_t*>(&seed), sizeof(seed), key_);
+
+ memset(buffer_, 0, sizeof(buffer_));
+ FillBuffer();
+}
+
MockFramerVisitor::MockFramerVisitor() {
// By default, we want to accept packets.
ON_CALL(*this, OnProtocolVersionMismatch(_, _))
