Home | History | Annotate | Download | only in crypto 
      1 // Copyright 2014 The Chromium Authors. All rights reserved.
      2 // Use of this source code is governed by a BSD-style license that can be
      3 // found in the LICENSE file.
      4 
      5 #include "net/quic/crypto/chacha20_poly1305_decrypter.h"
      6 
      7 #include <pk11pub.h>
      8 
      9 #include "base/logging.h"
     10 
     11 using base::StringPiece;
     12 
     13 namespace net {
     14 
     15 namespace {
     16 
     17 const size_t kKeySize = 32;
     18 const size_t kNoncePrefixSize = 0;
     19 
     20 }  // namespace
     21 
     22 #if defined(USE_NSS)
     23 
     24 // System NSS doesn't support ChaCha20+Poly1305 yet.
     25 
     26 ChaCha20Poly1305Decrypter::ChaCha20Poly1305Decrypter()
     27     : AeadBaseDecrypter(CKM_INVALID_MECHANISM, NULL, kKeySize,
     28                         kAuthTagSize, kNoncePrefixSize) {
     29   NOTIMPLEMENTED();
     30 }
     31 
     32 ChaCha20Poly1305Decrypter::~ChaCha20Poly1305Decrypter() {}
     33 
     34 // static
     35 bool ChaCha20Poly1305Decrypter::IsSupported() {
     36   return false;
     37 }
     38 
     39 void ChaCha20Poly1305Decrypter::FillAeadParams(StringPiece nonce,
     40                                                StringPiece associated_data,
     41                                                size_t auth_tag_size,
     42                                                AeadParams* aead_params) const {
     43   NOTIMPLEMENTED();
     44 }
     45 
     46 #else  // defined(USE_NSS)
     47 
     48 ChaCha20Poly1305Decrypter::ChaCha20Poly1305Decrypter()
     49     : AeadBaseDecrypter(CKM_NSS_CHACHA20_POLY1305, PK11_Decrypt, kKeySize,
     50                         kAuthTagSize, kNoncePrefixSize) {
     51   COMPILE_ASSERT(kKeySize <= kMaxKeySize, key_size_too_big);
     52   COMPILE_ASSERT(kNoncePrefixSize <= kMaxNoncePrefixSize,
     53                  nonce_prefix_size_too_big);
     54 }
     55 
     56 ChaCha20Poly1305Decrypter::~ChaCha20Poly1305Decrypter() {}
     57 
     58 // static
     59 bool ChaCha20Poly1305Decrypter::IsSupported() {
     60   return true;
     61 }
     62 
     63 void ChaCha20Poly1305Decrypter::FillAeadParams(StringPiece nonce,
     64                                                StringPiece associated_data,
     65                                                size_t auth_tag_size,
     66                                                AeadParams* aead_params) const {
     67   aead_params->len = sizeof(aead_params->data.nss_aead_params);
     68   CK_NSS_AEAD_PARAMS* nss_aead_params = &aead_params->data.nss_aead_params;
     69   nss_aead_params->pIv =
     70       reinterpret_cast<CK_BYTE*>(const_cast<char*>(nonce.data()));
     71   nss_aead_params->ulIvLen = nonce.size();
     72   nss_aead_params->pAAD =
     73       reinterpret_cast<CK_BYTE*>(const_cast<char*>(associated_data.data()));
     74   nss_aead_params->ulAADLen = associated_data.size();
     75   nss_aead_params->ulTagLen = auth_tag_size;
     76 }
     77 
     78 #endif  // defined(USE_NSS)
     79 
     80 }  // namespace net
     81