Added NetworkingPrivateCrypto for crypto part of networking private api and its unit test.

BUG=267667
TEST=unit_tests --gtest_filter=NetworkingPrivateCryptoTest.*

Review URL: https://chromiumcodereview.appspot.com/23710003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@221505 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/extensions/api/networking_private/networking_private_crypto.cc

+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/extensions/api/networking_private/networking_private_crypto.h"
+
+#include <cert.h>
+#include <cryptohi.h>
+#include <keyhi.h>
+#include <keythi.h>
+#include <pk11pub.h>
+#include <sechash.h>
+#include <secport.h>
+
+#include "base/base64.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/strings/string_number_conversions.h"
+#include "base/strings/string_util.h"
+#include "base/strings/stringprintf.h"
+#include "crypto/nss_util.h"
+#include "crypto/rsa_private_key.h"
+#include "crypto/scoped_nss_types.h"
+#include "net/cert/pem_tokenizer.h"
+#include "net/cert/x509_certificate.h"
+
+const unsigned char kTrustedCAPublicKeyDER[] = {
+  0x30, 0x82, 0x01, 0x0a, 0x02, 0x82, 0x01, 0x01, 0x00, 0xbc, 0x22, 0x80, 0xbd,
+  0x80, 0xf6, 0x3a, 0x21, 0x00, 0x3b, 0xae, 0x76, 0x5e, 0x35, 0x7f, 0x3d, 0xc3,
+  0x64, 0x5c, 0x55, 0x94, 0x86, 0x34, 0x2f, 0x05, 0x87, 0x28, 0xcd, 0xf7, 0x69,
+  0x8c, 0x17, 0xb3, 0x50, 0xa7, 0xb8, 0x82, 0xfa, 0xdf, 0xc7, 0x43, 0x2d, 0xd6,
+  0x7e, 0xab, 0xa0, 0x6f, 0xb7, 0x13, 0x72, 0x80, 0xa4, 0x47, 0x15, 0xc1, 0x20,
+  0x99, 0x50, 0xcd, 0xec, 0x14, 0x62, 0x09, 0x5b, 0xa4, 0x98, 0xcd, 0xd2, 0x41,
+  0xb6, 0x36, 0x4e, 0xff, 0xe8, 0x2e, 0x32, 0x30, 0x4a, 0x81, 0xa8, 0x42, 0xa3,
+  0x6c, 0x9b, 0x33, 0x6e, 0xca, 0xb2, 0xf5, 0x53, 0x66, 0xe0, 0x27, 0x53, 0x86,
+  0x1a, 0x85, 0x1e, 0xa7, 0x39, 0x3f, 0x4a, 0x77, 0x8e, 0xfb, 0x54, 0x66, 0x66,
+  0xfb, 0x58, 0x54, 0xc0, 0x5e, 0x39, 0xc7, 0xf5, 0x50, 0x06, 0x0b, 0xe0, 0x8a,
+  0xd4, 0xce, 0xe1, 0x6a, 0x55, 0x1f, 0x8b, 0x17, 0x00, 0xe6, 0x69, 0xa3, 0x27,
+  0xe6, 0x08, 0x25, 0x69, 0x3c, 0x12, 0x9d, 0x8d, 0x05, 0x2c, 0xd6, 0x2e, 0xa2,
+  0x31, 0xde, 0xb4, 0x52, 0x50, 0xd6, 0x20, 0x49, 0xde, 0x71, 0xa0, 0xf9, 0xad,
+  0x20, 0x40, 0x12, 0xf1, 0xdd, 0x25, 0xeb, 0xd5, 0xe6, 0xb8, 0x36, 0xf4, 0xd6,
+  0x8f, 0x7f, 0xca, 0x43, 0xdc, 0xd7, 0x10, 0x5b, 0xe6, 0x3f, 0x51, 0x8a, 0x85,
+  0xb3, 0xf3, 0xff, 0xf6, 0x03, 0x2d, 0xcb, 0x23, 0x4f, 0x9c, 0xad, 0x18, 0xe7,
+  0x93, 0x05, 0x8c, 0xac, 0x52, 0x9a, 0xf7, 0x4c, 0xe9, 0x99, 0x7a, 0xbe, 0x6e,
+  0x7e, 0x4d, 0x0a, 0xe3, 0xc6, 0x1c, 0xa9, 0x93, 0xfa, 0x3a, 0xa5, 0x91, 0x5d,
+  0x1c, 0xbd, 0x66, 0xeb, 0xcc, 0x60, 0xdc, 0x86, 0x74, 0xca, 0xcf, 0xf8, 0x92,
+  0x1c, 0x98, 0x7d, 0x57, 0xfa, 0x61, 0x47, 0x9e, 0xab, 0x80, 0xb7, 0xe4, 0x48,
+  0x80, 0x2a, 0x92, 0xc5, 0x1b, 0x02, 0x03, 0x01, 0x00, 0x01 };
+
+namespace {
+
+// Parses |pem_data| for a PEM block of |pem_type|.
+// Returns true if a |pem_type| block is found, storing the decoded result in
+// |der_output|.
+bool GetDERFromPEM(const std::string& pem_data,
+                   const std::string& pem_type,
+                   std::string* der_output) {
+  std::vector<std::string> headers;
+  headers.push_back(pem_type);
+  net::PEMTokenizer pem_tok(pem_data, headers);
+  if (!pem_tok.GetNext()) {
+    return false;
+  }
+
+  *der_output = pem_tok.data();
+  return true;
+}
+
+}  // namespace
+
+
+NetworkingPrivateCrypto::NetworkingPrivateCrypto() {}
+
+NetworkingPrivateCrypto::~NetworkingPrivateCrypto() {}
+
+bool NetworkingPrivateCrypto::VerifyCredentials(
+    const std::string& certificate,
+    const std::string& signature,
+    const std::string& data,
+    const std::string& connected_mac) {
+  crypto::EnsureNSSInit();
+
+  std::string cert_data;
+  if (!GetDERFromPEM(certificate, "CERTIFICATE", &cert_data)) {
+    LOG(ERROR) << "Failed to parse certificate.";
+    return false;
+  }
+  SECItem der_cert;
+  der_cert.type = siDERCertBuffer;
+  der_cert.data = reinterpret_cast<unsigned char*>(
+      const_cast<char*>(cert_data.c_str()));
+  der_cert.len = cert_data.length();
+
+  // Parse into a certificate structure.
+  typedef scoped_ptr_malloc<
+      CERTCertificate,
+      crypto::NSSDestroyer<CERTCertificate,
+                          CERT_DestroyCertificate> >
+      ScopedCERTCertificate;
+  ScopedCERTCertificate cert(CERT_NewTempCertificate(
+      CERT_GetDefaultCertDB(), &der_cert, NULL, PR_FALSE, PR_TRUE));
+  if (!cert.get()) {
+    LOG(ERROR) << "Failed to parse certificate.";
+    return false;
+  }
+
+  // Check that the certificate is signed by trusted CA.
+  SECItem trusted_ca_key_der_item;
+  trusted_ca_key_der_item.type = siDERCertBuffer;
+  trusted_ca_key_der_item.data = const_cast<unsigned char*>(
+      kTrustedCAPublicKeyDER),
+  trusted_ca_key_der_item.len = sizeof(kTrustedCAPublicKeyDER);
+  crypto::ScopedSECKEYPublicKey ca_public_key(
+      SECKEY_ImportDERPublicKey(&trusted_ca_key_der_item, CKK_RSA));
+  SECStatus verified = CERT_VerifySignedDataWithPublicKey(
+      &cert->signatureWrap, ca_public_key.get(), NULL);
+  if (verified != SECSuccess) {
+    LOG(ERROR) << "Certificate is not issued by the trusted CA.";
+    return false;
+  }
+
+  // Check that the device listed in the certificate is correct.
+  // Something like evt_e161 001a11ffacdf
+  char* common_name = CERT_GetCommonName(&cert->subject);
+  if (!common_name) {
+    LOG(ERROR) << "Certificate does not have common name.";
+    return false;
+  }
+
+  std::string subject_name(common_name);
+  PORT_Free(common_name);
+  std::string translated_mac;
+  RemoveChars(connected_mac, ":", &translated_mac);
+  if (!EndsWith(subject_name, translated_mac, false)) {
+    LOG(ERROR) << "MAC addresses don't match.";
+    return false;
+  }
+
+  // Make sure that the certificate matches the unsigned data presented.
+  // Verify that the |signature| matches |data|.
+  crypto::ScopedSECKEYPublicKey public_key(CERT_ExtractPublicKey(cert.get()));
+  if (!public_key.get()) {
+    LOG(ERROR) << "Unable to extract public key from certificate.";
+    return false;
+  }
+  SECItem signature_item;
+  signature_item.type = siBuffer;
+  signature_item.data = reinterpret_cast<unsigned char*>(
+      const_cast<char*>(signature.c_str()));
+  signature_item.len = static_cast<unsigned int>(signature.size());
+  verified = VFY_VerifyDataDirect(reinterpret_cast<unsigned char*>(
+      const_cast<char*>(data.c_str())), data.size(),
+      public_key.get(), &signature_item, SEC_OID_PKCS1_RSA_ENCRYPTION,
+      SEC_OID_SHA1, NULL, NULL);
+  if (verified != SECSuccess) {
+    LOG(ERROR) << "Signed blobs did not match.";
+    return false;
+  }
+  return true;
+}
+
+bool NetworkingPrivateCrypto::EncryptByteString(const std::string& pub_key_der,
+                                                const std::string& data,
+                                                std::string* encrypted_output) {
+  crypto::EnsureNSSInit();
+
+  SECItem pub_key_der_item;
+  pub_key_der_item.type = siDERCertBuffer;
+  pub_key_der_item.data = reinterpret_cast<unsigned char*>(
+      const_cast<char*>(pub_key_der.c_str()));
+  pub_key_der_item.len = pub_key_der.size();
+
+  crypto::ScopedSECKEYPublicKey public_key(SECKEY_ImportDERPublicKey(
+      &pub_key_der_item, CKK_RSA));
+  if (!public_key.get()) {
+    LOG(ERROR) << "Failed to parse public key.";
+    return false;
+  }
+
+  size_t encrypted_length = SECKEY_PublicKeyStrength(public_key.get());
+  // RSAES is defined as operating on messages up to a length of k - 11, where
+  // k is the octet length of the RSA modulus.
+  if (encrypted_length < data.size() + 11) {
+    LOG(ERROR) << "Too much data to encrypt.";
+    return false;
+  }
+
+  scoped_ptr<unsigned char[]> rsa_output(new unsigned char[encrypted_length]);
+  SECStatus encrypted = PK11_PubEncryptPKCS1(
+      public_key.get(),
+      rsa_output.get(),
+      reinterpret_cast<unsigned char*>(const_cast<char*>(data.data())),
+      data.length(),
+      NULL);
+  if (encrypted != SECSuccess) {
+    LOG(ERROR) << "Error during encryption.";
+    return false;
+  }
+  encrypted_output->assign(reinterpret_cast<char*>(rsa_output.get()),
+                           encrypted_length);
+  return true;
+}
+
+bool NetworkingPrivateCrypto::DecryptByteString(
+    const std::string& private_key_pem,
+    const std::string& encrypted_data,
+    std::string* decrypted_output) {
+  crypto::EnsureNSSInit();
+
+  std::string private_key_der;
+  if (!GetDERFromPEM(private_key_pem, "PRIVATE KEY", &private_key_der)) {
+    LOG(ERROR) << "Failed to parse private key PEM.";
+    return false;
+  }
+  std::vector<uint8> private_key_data(private_key_der.begin(),
+                                      private_key_der.end());
+  scoped_ptr<crypto::RSAPrivateKey> private_key(
+      crypto::RSAPrivateKey::CreateFromPrivateKeyInfo(private_key_data));
+  if (!private_key || !private_key->public_key()) {
+    LOG(ERROR) << "Failed to parse private key DER.";
+    return false;
+  }
+
+  size_t encrypted_length = SECKEY_SignatureLen(private_key->public_key());
+  scoped_ptr<unsigned char[]> rsa_output(new unsigned char[encrypted_length]);
+  unsigned int output_length = 0;
+  SECStatus decrypted =
+      PK11_PrivDecryptPKCS1(private_key->key(),
+                            rsa_output.get(),
+                            &output_length,
+                            encrypted_length,
+                            reinterpret_cast<unsigned char*>(
+                                const_cast<char*>(encrypted_data.data())),
+                            encrypted_data.length());
+  if (decrypted != SECSuccess) {
+    LOG(ERROR) << "Error during decryption.";
+    return false;
+  }
+  decrypted_output->assign(reinterpret_cast<char*>(rsa_output.get()),
+                           output_length);
+  return true;
+}
+

chrome/browser/extensions/api/networking_private/networking_private_crypto.h

+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROME_BROWSER_EXTENSIONS_API_NETWORKING_PRIVATE_NETWORKING_PRIVATE_CRYPTO_H_
+#define CHROME_BROWSER_EXTENSIONS_API_NETWORKING_PRIVATE_NETWORKING_PRIVATE_CRYPTO_H_
+
+#include <string>
+#include "base/basictypes.h"
+
+// Implementation of Crypto support for networking private API.
+// Based on chromeos_public//src/platform/shill/shims/crypto_util.cc
+class NetworkingPrivateCrypto {
+ public:
+  NetworkingPrivateCrypto();
+  ~NetworkingPrivateCrypto();
+
+  // Verify that credentials described by |certificate| and |signed_data| are
+  // valid.
+  //
+  // 1) The MAC address listed in the certificate matches |connected_mac|.
+  // 2) The certificate is a valid PEM encoded certificate signed by trusted CA.
+  // 3) |signature| is a valid signature for |data|, using the public key in
+  // |certificate|
+  bool VerifyCredentials(const std::string& certificate,
+                         const std::string& signature,
+                         const std::string& data,
+                         const std::string& connected_mac);
+
+  // Encrypt |data| with |public_key|. |public_key| is a DER-encoded
+  // RSAPublicKey. |data| is some string of bytes at smaller than the
+  // maximum length permissable for encryption with a key of |public_key| size.
+  //
+  // Returns true on success, storing the encrypted result in
+  // |encrypted_output|.
+  bool EncryptByteString(const std::string& public_key,
+                         const std::string& data,
+                         std::string* encrypted_output);
+
+ private:
+  friend class NetworkingPrivateCryptoTest;
+
+  // Decrypt |encrypted_data| with |private_key_pem|. |private_key_pem| is the
+  // PKCS8 PEM-encoded private key. |encrypted_data| is data encrypted with
+  // EncryptByteString. Used in NetworkingPrivateCryptoTest::EncryptString test.
+  //
+  // Returns true on success, storing the decrypted result in
+  // |decrypted_output|.
+  bool DecryptByteString(const std::string& private_key_pem,
+                         const std::string& encrypted_data,
+                         std::string* decrypted_output);
+
+  DISALLOW_COPY_AND_ASSIGN(NetworkingPrivateCrypto);
+};
+
+#endif  // CHROME_BROWSER_EXTENSIONS_API_NETWORKING_PRIVATE_NETWORKING_PRIVATE_CRYPTO_H_
+

chrome/browser/extensions/api/networking_private/networking_private_crypto_unittest.cc

+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/base64.h"
+#include "base/logging.h"
+#include "base/strings/stringprintf.h"
+#include "chrome/browser/extensions/api/networking_private/networking_private_crypto.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+// Tests of NetworkingPrivateCrypto support for Networking Private API.
+// Based on chromeos_public//.../network_DestinationVerification.py
+class NetworkingPrivateCryptoTest : public testing::Test {
+ protected:
+  // Verify that decryption of |encrypted| data using |private_key_pem| matches
+  // |plain| data.
+  bool VerifyByteString(const std::string& private_key_pem,
+                        const std::string& plain,
+                        const std::string& encrypted) {
+    NetworkingPrivateCrypto crypto;
+    std::string decrypted;
+    if (crypto.DecryptByteString(private_key_pem, encrypted, &decrypted))
+      return decrypted == plain;
+    return false;
+  }
+};
+
+// Test that NetworkingPrivateCrypto::VerifyCredentials behaves as expected.
+TEST_F(NetworkingPrivateCryptoTest, VerifyCredentials) {
+  static const char kCertData[] =
+      "-----BEGIN CERTIFICATE-----"
+      "MIIDhzCCAm8CBFE2SCMwDQYJKoZIhvcNAQEFBQAwfTELMAkGA1UEBhMCVVMxEzARBgNVBAgM"
+      "CkNhbGlmb3JuaWExFjAUBgNVBAcMDU1vdW50YWluIFZpZXcxEzARBgNVBAoMCkdvb2dsZSBJ"
+      "bmMxEjAQBgNVBAsMCUdvb2dsZSBUVjEYMBYGA1UEAwwPRXVyZWthIEdlbjEgSUNBMB4XDTEz"
+      "MDMwNTE5MzE0N1oXDTMzMDIyODE5MzE0N1owgYMxFjAUBgNVBAcTDU1vdW50YWluIFZpZXcx"
+      "EjAQBgNVBAsTCUdvb2dsZSBUVjETMBEGA1UEChMKR29vZ2xlIEluYzETMBEGA1UECBMKQ2Fs"
+      "aWZvcm5pYTELMAkGA1UEBhMCVVMxHjAcBgNVBAMUFWV2dF9lMTYxIDAwMWExMWZmYWNkZjCC"
+      "ASIwDQYJKoZIhvcNAQEBBQADggEPADCCAQoCggEBAPHGDV0lLoTYK78q13y/2u77YTjgbBlW"
+      "AOxgrSNcMmGHx1K0aPyo50p99dGQnjapW6jtGrMzReWV2Wz3VL8rYlqY7oWjeJwsLQwo2tcn"
+      "7vIZ/PuvPz9xgnGMUbBOfhCf3Epb1N4Jz82pxxrOFhUawWAglC9C4fUeZLCZpOJsQd4QeAzn"
+      "kydl3xbqdSm74kwxE6vkGEzSCDnC7aYx0Rvvr1mZOKdl4AinYrxzWgmVsTnaFT1soSjmC5e/"
+      "i6Jcrs4dDFgY6mKy9Qtly2XPSCYljm6L4SgqgJNmlpY0qYJgO++BdofIbU2jsOiCMvIuKkbM"
+      "n72NsPQG0QhnVMwk7kYg6kkCAwEAAaMNMAswCQYDVR0TBAIwADANBgkqhkiG9w0BAQUFAAOC"
+      "AQEAW0bQl9yjBc7DgMp94i7ZDOUxKQrzthephuwzb3/wWiTHcw6KK6FRPefXn6NPWxKKeQmv"
+      "/tBxHbVlmYRXUbrhksnD0aUki4InvtL2m0H1fPfMxmJRFE+HoSXu+s0sGON831JaMcYRbAku"
+      "5uHnltaGNzOI0KPHFGoCDmjAZD+IuoR2LR4FuuTrECK7KLjkdf//z5d5j7nBDPZS7uTCwC/B"
+      "wM9asRj3tJA5VRFbLbsit1VI7IaRCk9rsSKkpBUaVeKbPLz+y/Z6JonXXT6AxsfgUSKDd4B7"
+      "MYLrTwMQfGuUaaaKko6ldKIrovjrcPloQr1Hxb2bipFcjLmG7nxQLoS6vQ=="
+      "-----END CERTIFICATE-----";
+  static const char kName[] = "eureka8997";
+  static const char kSsdpUdn[] = "c5b2a83b-5958-7ce6-b179-e1f44699429b";
+  static const char kHotspotBssid[] = "00:1A:11:FF:AC:DF";
+  static const char kPublicKey[] =
+      "MIGJAoGBAK3SXmWZBOhJibv8It05qIbgHXXhnCXxHkW+C6jNMHR5sZgDpFaOY1xwXERjKdJx"
+      "cwrEy3VAT5Uv9MgHPBvxxJku76HYh1yVfIw1rhLnHBTHSxwUzJNCrgc3l3t/UACacLjVNIzc"
+      "cDpYf2vnOcA+t1t6IXRjzuU2NdwY4dJXNtWPAgMBAAE=";
+  static const char kNonce[] = "+6KSGuRu833m1+TP";
+  static const char kSignedData[] =
+      "vwMBgANrp5XpCswLyk/OTXT56ORPeIWjH7xAdCk3qgjkwI6+8o56zJS02+tC5hhIHWh7oppT"
+      "mWYF4tKvBQ3GeCz7IW9f7HWDMtO7x7yRWxzJyehaJbCfXvLdfs0/WKllzvGVBgNpcIAwU2NS"
+      "FUG/jpXclntFzds0EUJG9wHxS6PXXSYRu+PlIFdCDcQJsUlnwO9AGFOJRV/aARGh8YUTWCFI"
+      "QPOtPEqT5eegt+TLf01Gq0YcrRwSTKy1I3twOnWiMfIdkJdQKPtBwwbvuAyGuqYFocfjKABb"
+      "nH9Tvl04yyO3euKbYlSqaF/l8CXmzDJTyO7tDOFK59bV9auE4KljrQ==";
+  static const char kBadSubjectCertData[] =
+      "-----BEGIN CERTIFICATE-----"
+      "MIIDejCCAmICBFEtN4wwDQYJKoZIhvcNAQEFBQAwfTELMAkGA1UEBhMCVVMxEzARBgNVBAgM"
+      "CkNhbGlmb3JuaWExFjAUBgNVBAcMDU1vdW50YWluIFZpZXcxEzARBgNVBAoMCkdvb2dsZSBJ"
+      "bmMxEjAQBgNVBAsMCUdvb2dsZSBUVjEYMBYGA1UEAwwPRXVyZWthIEdlbjEgSUNBMB4XDTEz"
+      "MDIyNjIyMzAzNloXDTMzMDIyMTIyMzAzNlowdzETMBEGA1UECBMKQ2FsaWZvcm5pYTELMAkG"
+      "A1UEBhMCVVMxFjAUBgNVBAcTDU1vdW50YWluIFZpZXcxEjAQBgNVBAsTCUdvb2dsZSBUVjET"
+      "MBEGA1UEChMKR29vZ2xlIEluYzESMBAGA1UEAxQJZXZ0X2UxMjYyMIIBIjANBgkqhkiG9w0B"
+      "AQEFAAOCAQ8AMIIBCgKCAQEAo7Uu+bdyCjtiUYpmNU4ZvRjDg6VkEh/g0YPDG2pICBU4XKvs"
+      "qHH1i0hbtWp1J79hV9Rqst1yHT02Oeh3o1SOd2zeamYzmvXRVN7AZqfQlzWxwxk/ltpXGwew"
+      "m+EIR2bP4kpvyEKvvziTMtTxviOK+A395QyodMhMXClKTus/Gme2r1fBoQqJJR/zrmwXCsl5"
+      "kpdhj7FOIII3BCYV0zejjQquzywjsKfCVON28VGgJdaKgmXxkeRYYWVNnuTNna57vXe16FP6"
+      "hS1ty1U77ESffLTpNJ/M4tsd2dMVVTDuGeX3q8Ix4TN8cqpqu1AKEf59hygys9j6cHZRKR/d"
+      "iv0+uQIDAQABow0wCzAJBgNVHRMEAjAAMA0GCSqGSIb3DQEBBQUAA4IBAQAZx6XyEK9SLHE+"
+      "rbKCVsLN9+hTEa50aikPmxOZt+lFuB4+VJZ/GCPQCZJIde2tlWUe2YBgoZw2xUKgIsM3Yq42"
+      "Gawi35/oZ3qycTgYU8KJP9kUMbYNAH90mz9BDH7MmnRID5dFexHyBCG88EJ+ZvxmUVn0EVDc"
+      "sSMt11wIAZ/T+/gsE1120d/GxhjYQ9YZz7SZXBQfRdqCdcPNl2+QSHHl+WvYLzdJa2xYj39/"
+      "kQu47Vp7X5rZrHSBvzdVymH0Od2D18t+Q6lxbSdyUNhP1MVhdkT1Ct4OmRS3FJ4aannXMhfq"
+      "Ng7k4Sfif5iktYT4VRKpThe0EGJNfqKJKYtvHEVC"
+      "-----END CERTIFICATE-----";
+  static const char kBadCertData[] = "not a certificate";
+  static const char kBadNonce[] = "bad nonce";
+  static const char kBadHotspotBssid[] = "bad bssid";
+
+  std::string unsigned_data = base::StringPrintf(
+      "%s,%s,%s,%s,%s", kName, kSsdpUdn, kHotspotBssid, kPublicKey, kNonce);
+  std::string signed_data;
+  base::Base64Decode(kSignedData, &signed_data);
+
+  NetworkingPrivateCrypto crypto;
+  // Checking basic verification operation.
+  EXPECT_TRUE(crypto.VerifyCredentials(
+      kCertData, signed_data, unsigned_data, kHotspotBssid));
+
+  // Checking that verification fails when the certificate is signed, but
+  // subject is malformed.
+  EXPECT_FALSE(crypto.VerifyCredentials(
+      kBadSubjectCertData, signed_data, unsigned_data, kHotspotBssid));
+
+  // Checking that verification fails when certificate has invalid format.
+  EXPECT_FALSE(crypto.VerifyCredentials(
+      kBadCertData, signed_data, unsigned_data, kHotspotBssid));
+
+  // Checking that verification fails when Hotspot Bssid is invalid.
+  EXPECT_FALSE(crypto.VerifyCredentials(
+      kCertData, signed_data, unsigned_data, kBadHotspotBssid));
+
+  // Checking that verification fails when there is bad nonce in unsigned_data.
+  unsigned_data = base::StringPrintf(
+      "%s,%s,%s,%s,%s", kName, kSsdpUdn, kHotspotBssid, kPublicKey, kBadNonce);
+  EXPECT_FALSE(crypto.VerifyCredentials(
+      kCertData, signed_data, unsigned_data, kHotspotBssid));
+}
+
+// Test that NetworkingPrivateCrypto::EncryptByteString behaves as expected.
+TEST_F(NetworkingPrivateCryptoTest, EncryptByteString) {
+  NetworkingPrivateCrypto crypto;
+  static const char kPublicKey[] =
+      "MIGJAoGBANTjeoILNkSKHVkd3my/rSwNi+9t473vPJU0lkM8nn9C7+gmaPvEWg4ZNkMd12aI"
+      "XDXVHrjgjcS80bPE0ykhN9J7EYkJ+43oulJMrEnyDy5KQo7U3MKBdjaKFTS+OPyohHpI8GqH"
+      "KM8UMkLPVtAKu1BXgGTSDvEaBAuoVT2PM4XNAgMBAAE=";
+  static const char kPrivateKey[] =
+      "-----BEGIN PRIVATE KEY-----"
+      "MIICdwIBADANBgkqhkiG9w0BAQEFAASCAmEwggJdAgEAAoGBANTjeoILNkSKHVkd"
+      "3my/rSwNi+9t473vPJU0lkM8nn9C7+gmaPvEWg4ZNkMd12aIXDXVHrjgjcS80bPE"
+      "0ykhN9J7EYkJ+43oulJMrEnyDy5KQo7U3MKBdjaKFTS+OPyohHpI8GqHKM8UMkLP"
+      "VtAKu1BXgGTSDvEaBAuoVT2PM4XNAgMBAAECgYEAt91H/2zjj8qhkkhDxDS/wd5p"
+      "T37fRTmMX2ktpiCC23LadOxHm7p39Nk9jjYFxV5cFXpdsFrw1kwl6VdC8LDp3eGu"
+      "Ku1GCqj5H2fpnkmL2goD01HRkPR3ro4uBHPtTXDbCIz0qp+NGlGG4gPUysMXxHSb"
+      "E5FIWeUx6gcPvidwrpkCQQD40FXY46KDJT8JVYJMqY6nFQZvptFl+9BGWfheVVSF"
+      "KBlTQBx/QA+XcC/W9Q/I+NEhdGcxLlkEMUpihSpYffKbAkEA2wmFfccdheTtoOuY"
+      "8oTurbnFHsS7gLtcR2IbRJKXw80CJxTQA/LMWz0YuFOAYJNl/9ILMfp6MQiI4L9F"
+      "l6pbtwJAJqkAXcXo72WvKL0flNfXsYBj0p9h8+2vi+7Y15d8nYAAh13zz5XdllM5"
+      "K7ZCMKDwpbkXe53O+QbLnwk/7iYLtwJAERT6AygfJk0HNzCIeglh78x4EgE3uj9i"
+      "X/LHu55PFacMTu3xlw09YLQwFFf2wBFeuAeyddBZ7S8ENbrU+5H+mwJBAO2E6gwG"
+      "e5ZqY4RmsQmv6K0rn5k+UT4qlPeVp1e6LnvO/PcKWOaUvDK59qFZoX4vN+iFUAbk"
+      "IuvhmL9u/uPWWck="
+      "-----END PRIVATE KEY-----";
+  static const char kBadKeyData[] = "bad key";
+  static const char kTestData[] = "disco boy";
+  static const char kEmptyData[] = "";
+
+
+  std::string public_key;
+  base::Base64Decode(kPublicKey, &public_key);
+
+  std::string plain;
+  std::string encrypted_output;
+
+  // Checking basic encryption operation.
+  plain = kTestData;
+  EXPECT_TRUE(crypto.EncryptByteString(public_key, plain, &encrypted_output));
+  EXPECT_TRUE(VerifyByteString(kPrivateKey, plain, encrypted_output));
+
+  // Checking that we can encrypt the empty string.
+  plain = kEmptyData;
+  EXPECT_TRUE(crypto.EncryptByteString(public_key, plain, &encrypted_output));
+
+  // Checking graceful fail for too much data to encrypt.
+  EXPECT_FALSE(
+      crypto.EncryptByteString(public_key,
+                               std::string(500, 'x'),
+                               &encrypted_output));
+
+  // Checking graceful fail for a bad key format.
+  EXPECT_FALSE(
+      crypto.EncryptByteString(kBadKeyData, kTestData, &encrypted_output));
+}
+

chrome/chrome_browser_extensions.gypi

@@ -340,6 +340,8 @@
         'browser/extensions/api/networking_private/networking_private_api_chromeos.cc',
         'browser/extensions/api/networking_private/networking_private_api_nonchromeos.cc',
         'browser/extensions/api/networking_private/networking_private_api.h',
+        'browser/extensions/api/networking_private/networking_private_crypto.cc',
+        'browser/extensions/api/networking_private/networking_private_crypto.h',
         'browser/extensions/api/networking_private/networking_private_event_router_chromeos.cc',
         'browser/extensions/api/networking_private/networking_private_event_router.h',
         'browser/extensions/api/networking_private/networking_private_event_router_factory.cc',

chrome/chrome_tests_unit.gypi

@@ -817,6 +817,7 @@
         'browser/extensions/api/log_private/syslog_parser_unittest.cc',
         'browser/extensions/api/messaging/native_message_process_host_unittest.cc',
         'browser/extensions/api/messaging/native_messaging_host_manifest_unittest.cc',
+        'browser/extensions/api/networking_private/networking_private_crypto_unittest.cc',
         'browser/extensions/api/omnibox/omnibox_unittest.cc',
         'browser/extensions/api/permissions/permissions_api_helpers_unittest.cc',
         'browser/extensions/api/power/power_api_unittest.cc',