content/child/webcrypto/openssl/rsa_oaep_openssl.cc

   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 <openssl/evp.h>
   6
   7 #include "base/stl_util.h"
   8 #include "content/child/webcrypto/crypto_data.h"
   9 #include "content/child/webcrypto/openssl/key_openssl.h"
  10 #include "content/child/webcrypto/openssl/rsa_hashed_algorithm_openssl.h"
  11 #include "content/child/webcrypto/openssl/util_openssl.h"
  12 #include "content/child/webcrypto/status.h"
  13 #include "crypto/openssl_util.h"
  14 #include "crypto/scoped_openssl_types.h"
  15 #include "third_party/WebKit/public/platform/WebCryptoAlgorithmParams.h"
  16 #include "third_party/WebKit/public/platform/WebCryptoKeyAlgorithm.h"
  17
  18 namespace content {
  19
  20 namespace webcrypto {
  21
  22 namespace {
  23
  24 typedef int (*InitFunc)(EVP_PKEY_CTX* ctx);
  25 typedef int (*EncryptDecryptFunc)(EVP_PKEY_CTX* ctx,
  26                                   unsigned char* out,
  27                                   size_t* outlen,
  28                                   const unsigned char* in,
  29                                   size_t inlen);
  30
  31 // Helper for doing either RSA-OAEP encryption or decryption.
  32 //
  33 // To encrypt call with:
  34 //   init_func=EVP_PKEY_encrypt_init, encrypt_decrypt_func=EVP_PKEY_encrypt
  35 //
  36 // To decrypt call with:
  37 //   init_func=EVP_PKEY_decrypt_init, encrypt_decrypt_func=EVP_PKEY_decrypt
  38 Status CommonEncryptDecrypt(InitFunc init_func,
  39                             EncryptDecryptFunc encrypt_decrypt_func,
  40                             const blink::WebCryptoAlgorithm& algorithm,
  41                             const blink::WebCryptoKey& key,
  42                             const CryptoData& data,
  43                             std::vector<uint8_t>* buffer) {
  44   crypto::OpenSSLErrStackTracer err_tracer(FROM_HERE);
  45
  46   EVP_PKEY* pkey = AsymKeyOpenSsl::Cast(key)->key();
  47   const EVP_MD* digest =
  48       GetDigest(key.algorithm().rsaHashedParams()->hash().id());
  49   if (!digest)
  50     return Status::ErrorUnsupported();
  51
  52   crypto::ScopedEVP_PKEY_CTX ctx(EVP_PKEY_CTX_new(pkey, NULL));
  53
  54   if (!init_func(ctx.get()) ||
  55       1 != EVP_PKEY_CTX_set_rsa_padding(ctx.get(), RSA_PKCS1_OAEP_PADDING) ||
  56       1 != EVP_PKEY_CTX_set_rsa_oaep_md(ctx.get(), digest) ||
  57       1 != EVP_PKEY_CTX_set_rsa_mgf1_md(ctx.get(), digest)) {
  58     return Status::OperationError();
  59   }
  60
  61   const blink::WebVector<uint8_t>& label =
  62       algorithm.rsaOaepParams()->optionalLabel();
  63
  64   if (label.size()) {
  65     // Make a copy of the label, since the ctx takes ownership of it when
  66     // calling set0_rsa_oaep_label().
  67     crypto::ScopedOpenSSLBytes label_copy;
  68     label_copy.reset(static_cast<uint8_t*>(OPENSSL_malloc(label.size())));
  69     memcpy(label_copy.get(), label.data(), label.size());
  70
  71     if (1 != EVP_PKEY_CTX_set0_rsa_oaep_label(ctx.get(), label_copy.release(),
  72                                               label.size())) {
  73       return Status::OperationError();
  74     }
  75   }
  76
  77   // Determine the maximum length of the output.
  78   size_t outlen = 0;
  79   if (!encrypt_decrypt_func(ctx.get(), NULL, &outlen, data.bytes(),
  80                             data.byte_length())) {
  81     return Status::OperationError();
  82   }
  83   buffer->resize(outlen);
  84
  85   // Do the actual encryption/decryption.
  86   if (!encrypt_decrypt_func(ctx.get(), vector_as_array(buffer), &outlen,
  87                             data.bytes(), data.byte_length())) {
  88     return Status::OperationError();
  89   }
  90   buffer->resize(outlen);
  91
  92   return Status::Success();
  93 }
  94
  95 class RsaOaepImplementation : public RsaHashedAlgorithm {
  96  public:
  97   RsaOaepImplementation()
  98       : RsaHashedAlgorithm(
  99             blink::WebCryptoKeyUsageEncrypt | blink::WebCryptoKeyUsageWrapKey,
 100             blink::WebCryptoKeyUsageDecrypt |
 101                 blink::WebCryptoKeyUsageUnwrapKey) {}
 102
 103   const char* GetJwkAlgorithm(
 104       const blink::WebCryptoAlgorithmId hash) const override {
 105     switch (hash) {
 106       case blink::WebCryptoAlgorithmIdSha1:
 107         return "RSA-OAEP";
 108       case blink::WebCryptoAlgorithmIdSha256:
 109         return "RSA-OAEP-256";
 110       case blink::WebCryptoAlgorithmIdSha384:
 111         return "RSA-OAEP-384";
 112       case blink::WebCryptoAlgorithmIdSha512:
 113         return "RSA-OAEP-512";
 114       default:
 115         return NULL;
 116     }
 117   }
 118
 119   Status Encrypt(const blink::WebCryptoAlgorithm& algorithm,
 120                  const blink::WebCryptoKey& key,
 121                  const CryptoData& data,
 122                  std::vector<uint8_t>* buffer) const override {
 123     if (key.type() != blink::WebCryptoKeyTypePublic)
 124       return Status::ErrorUnexpectedKeyType();
 125
 126     return CommonEncryptDecrypt(EVP_PKEY_encrypt_init, EVP_PKEY_encrypt,
 127                                 algorithm, key, data, buffer);
 128   }
 129
 130   Status Decrypt(const blink::WebCryptoAlgorithm& algorithm,
 131                  const blink::WebCryptoKey& key,
 132                  const CryptoData& data,
 133                  std::vector<uint8_t>* buffer) const override {
 134     if (key.type() != blink::WebCryptoKeyTypePrivate)
 135       return Status::ErrorUnexpectedKeyType();
 136
 137     return CommonEncryptDecrypt(EVP_PKEY_decrypt_init, EVP_PKEY_decrypt,
 138                                 algorithm, key, data, buffer);
 139   }
 140 };
 141
 142 }  // namespace
 143
 144 AlgorithmImplementation* CreatePlatformRsaOaepImplementation() {
 145   return new RsaOaepImplementation;
 146 }
 147
 148 }  // namespace webcrypto
 149
 150 }  // namespace content