1 files changed, 148 insertions, 0 deletions
diff --git a/security/nss/gtests/ssl_gtest/tls_protect.cc b/security/nss/gtests/ssl_gtest/tls_protect.cc
new file mode 100644
index 0000000000..6187660a5c
--- /dev/null
+++ b/security/nss/gtests/ssl_gtest/tls_protect.cc
@@ -0,0 +1,148 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=2 et sw=2 tw=80: */
+/* 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 "tls_protect.h"
+#include "sslproto.h"
+#include "tls_filter.h"
+
+namespace nss_test {
+
+static uint64_t FirstSeqno(bool dtls, uint16_t epoc) {
+  if (dtls) {
+    return static_cast<uint64_t>(epoc) << 48;
+  }
+  return 0;
+}
+
+TlsCipherSpec::TlsCipherSpec(bool dtls, uint16_t epoc)
+    : dtls_(dtls),
+      epoch_(epoc),
+      in_seqno_(FirstSeqno(dtls, epoc)),
+      out_seqno_(FirstSeqno(dtls, epoc)) {}
+
+bool TlsCipherSpec::SetKeys(SSLCipherSuiteInfo* cipherinfo,
+                            PK11SymKey* secret) {
+  SSLAeadContext* aead_ctx;
+  SSLProtocolVariant variant =
+      dtls_ ? ssl_variant_datagram : ssl_variant_stream;
+  SECStatus rv =
+      SSL_MakeVariantAead(SSL_LIBRARY_VERSION_TLS_1_3, cipherinfo->cipherSuite,
+                          variant, secret, "", 0,  // Use the default labels.
+                          &aead_ctx);
+  if (rv != SECSuccess) {
+    return false;
+  }
+  aead_.reset(aead_ctx);
+
+  SSLMaskingContext* mask_ctx;
+  const char kHkdfPurposeSn[] = "sn";
+  rv = SSL_CreateVariantMaskingContext(
+      SSL_LIBRARY_VERSION_TLS_1_3, cipherinfo->cipherSuite, variant, secret,
+      kHkdfPurposeSn, strlen(kHkdfPurposeSn), &mask_ctx);
+  if (rv != SECSuccess) {
+    return false;
+  }
+  mask_.reset(mask_ctx);
+  return true;
+}
+
+bool TlsCipherSpec::Unprotect(const TlsRecordHeader& header,
+                              const DataBuffer& ciphertext,
+                              DataBuffer* plaintext,
+                              TlsRecordHeader* out_header) {
+  if (!aead_ || !out_header) {
+    return false;
+  }
+  *out_header = header;
+
+  // Make space.
+  plaintext->Allocate(ciphertext.len());
+
+  unsigned int len;
+  uint64_t seqno = dtls_ ? header.sequence_number() : in_seqno_;
+  SECStatus rv;
+
+  if (header.is_dtls13_ciphertext()) {
+    if (!mask_ || !out_header) {
+      return false;
+    }
+    PORT_Assert(ciphertext.len() >= 16);
+    DataBuffer mask(2);
+    rv = SSL_CreateMask(mask_.get(), ciphertext.data(), ciphertext.len(),
+                        mask.data(), mask.len());
+    if (rv != SECSuccess) {
+      return false;
+    }
+
+    if (!out_header->MaskSequenceNumber(mask)) {
+      return false;
+    }
+    seqno = out_header->sequence_number();
+  }
+
+  auto header_bytes = out_header->header();
+  rv = SSL_AeadDecrypt(aead_.get(), seqno, header_bytes.data(),
+                       header_bytes.len(), ciphertext.data(), ciphertext.len(),
+                       plaintext->data(), &len, plaintext->len());
+  if (rv != SECSuccess) {
+    return false;
+  }
+
+  RecordUnprotected(seqno);
+  plaintext->Truncate(static_cast<size_t>(len));
+
+  return true;
+}
+
+bool TlsCipherSpec::Protect(const TlsRecordHeader& header,
+                            const DataBuffer& plaintext, DataBuffer* ciphertext,
+                            TlsRecordHeader* out_header) {
+  if (!aead_ || !out_header) {
+    return false;
+  }
+
+  *out_header = header;
+
+  // Make a padded buffer.
+  ciphertext->Allocate(plaintext.len() +
+                       32);  // Room for any plausible auth tag
+  unsigned int len;
+
+  DataBuffer header_bytes;
+  (void)header.WriteHeader(&header_bytes, 0, plaintext.len() + 16);
+  uint64_t seqno = dtls_ ? header.sequence_number() : out_seqno_;
+
+  SECStatus rv =
+      SSL_AeadEncrypt(aead_.get(), seqno, header_bytes.data(),
+                      header_bytes.len(), plaintext.data(), plaintext.len(),
+                      ciphertext->data(), &len, ciphertext->len());
+  if (rv != SECSuccess) {
+    return false;
+  }
+
+  if (header.is_dtls13_ciphertext()) {
+    if (!mask_ || !out_header) {
+      return false;
+    }
+    PORT_Assert(ciphertext->len() >= 16);
+    DataBuffer mask(2);
+    rv = SSL_CreateMask(mask_.get(), ciphertext->data(), ciphertext->len(),
+                        mask.data(), mask.len());
+    if (rv != SECSuccess) {
+      return false;
+    }
+    if (!out_header->MaskSequenceNumber(mask)) {
+      return false;
+    }
+  }
+
+  RecordProtected();
+  ciphertext->Truncate(len);
+
+  return true;
+}
+
+}  // namespace nss_test