// 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 "gtest/gtest.h"

#include <stdint.h>
#include <memory>

#include "blapi.h"
#include "secitem.h"
#include "freebl_scoped_ptrs.h"

class CmacAesTest : public ::testing::Test {
 protected:
  bool Compare(const uint8_t *actual, const uint8_t *expected,
               unsigned int length) {
    return strncmp((const char *)actual, (const char *)expected, length) == 0;
  }
};

TEST_F(CmacAesTest, CreateInvalidSize) {
  uint8_t key[1] = {0x00};
  ScopedCMACContext ctx(CMAC_Create(CMAC_AES, key, sizeof(key)));
  ASSERT_EQ(ctx, nullptr);
}

TEST_F(CmacAesTest, CreateRightSize) {
  uint8_t *key = PORT_NewArray(uint8_t, AES_128_KEY_LENGTH);
  ScopedCMACContext ctx(CMAC_Create(CMAC_AES, key, AES_128_KEY_LENGTH));

  ASSERT_NE(ctx, nullptr);
  PORT_Free(key);
}

// The following tests were taken from NIST's Cryptographic Standards and
// Guidelines page for AES-CMAC Examples with Intermediate Values. These same
// test vectors for AES-128 can be found in RFC 4493, Section 4.

static const uint8_t kNistKeys[][AES_256_KEY_LENGTH] = {
    {0x2B, 0x7E, 0x15, 0x16, 0x28, 0xAE, 0xD2, 0xA6, 0xAB, 0xF7, 0x15,
     0x88, 0x09, 0xCF, 0x4F, 0x3C, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
    {0x8E, 0x73, 0xB0, 0xF7, 0xDA, 0x0E, 0x64, 0x52, 0xC8, 0x10, 0xF3,
     0x2B, 0x80, 0x90, 0x79, 0xE5, 0x62, 0xF8, 0xEA, 0xD2, 0x52, 0x2C,
     0x6B, 0x7B, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
    {0x60, 0x3D, 0xEB, 0x10, 0x15, 0xCA, 0x71, 0xBE, 0x2B, 0x73, 0xAE,
     0xF0, 0x85, 0x7D, 0x77, 0x81, 0x1F, 0x35, 0x2C, 0x07, 0x3B, 0x61,
     0x08, 0xD7, 0x2D, 0x98, 0x10, 0xA3, 0x09, 0x14, 0xDF, 0xF4}};
static const size_t kNistKeyLengthsCount = PR_ARRAY_SIZE(kNistKeys);
static const unsigned int kNistKeyLengths[kNistKeyLengthsCount] = {
    AES_128_KEY_LENGTH, AES_192_KEY_LENGTH, AES_256_KEY_LENGTH};

static const uint8_t kNistPlaintext[64] = {
    0x6B, 0xC1, 0xBE, 0xE2, 0x2E, 0x40, 0x9F, 0x96, 0xE9, 0x3D, 0x7E,
    0x11, 0x73, 0x93, 0x17, 0x2A, 0xAE, 0x2D, 0x8A, 0x57, 0x1E, 0x03,
    0xAC, 0x9C, 0x9E, 0xB7, 0x6F, 0xAC, 0x45, 0xAF, 0x8E, 0x51, 0x30,
    0xC8, 0x1C, 0x46, 0xA3, 0x5C, 0xE4, 0x11, 0xE5, 0xFB, 0xC1, 0x19,
    0x1A, 0x0A, 0x52, 0xEF, 0xF6, 0x9F, 0x24, 0x45, 0xDF, 0x4F, 0x9B,
    0x17, 0xAD, 0x2B, 0x41, 0x7B, 0xE6, 0x6C, 0x37, 0x10};
static const unsigned int kNistPlaintextLengths[] = {0, 16, 20, 64};
static const size_t kNistPlaintextLengthsCount =
    PR_ARRAY_SIZE(kNistPlaintextLengths);

// This table contains the result of a CMAC over kNistPlaintext using keys from
// kNistKeys.  For each key, there are kNistPlaintextLengthsCount answers, all
// listed one after the other as the input is truncated to the different sizes
// in kNistPlaintextLengths.
static const uint8_t kNistKnown[][AES_BLOCK_SIZE] = {
    {0xBB, 0x1D, 0x69, 0x29, 0xE9, 0x59, 0x37, 0x28, 0x7F, 0xA3, 0x7D, 0x12,
     0x9B, 0x75, 0x67, 0x46},
    {0x07, 0x0A, 0x16, 0xB4, 0x6B, 0x4D, 0x41, 0x44, 0xF7, 0x9B, 0xDD, 0x9D,
     0xD0, 0x4A, 0x28, 0x7C},
    {0x7D, 0x85, 0x44, 0x9E, 0xA6, 0xEA, 0x19, 0xC8, 0x23, 0xA7, 0xBF, 0x78,
     0x83, 0x7D, 0xFA, 0xDE},
    {0x51, 0xF0, 0xBE, 0xBF, 0x7E, 0x3B, 0x9D, 0x92, 0xFC, 0x49, 0x74, 0x17,
     0x79, 0x36, 0x3C, 0xFE},
    {0xD1, 0x7D, 0xDF, 0x46, 0xAD, 0xAA, 0xCD, 0xE5, 0x31, 0xCA, 0xC4, 0x83,
     0xDE, 0x7A, 0x93, 0x67},
    {0x9E, 0x99, 0xA7, 0xBF, 0x31, 0xE7, 0x10, 0x90, 0x06, 0x62, 0xF6, 0x5E,
     0x61, 0x7C, 0x51, 0x84},
    {0x3D, 0x75, 0xC1, 0x94, 0xED, 0x96, 0x07, 0x04, 0x44, 0xA9, 0xFA, 0x7E,
     0xC7, 0x40, 0xEC, 0xF8},
    {0xA1, 0xD5, 0xDF, 0x0E, 0xED, 0x79, 0x0F, 0x79, 0x4D, 0x77, 0x58, 0x96,
     0x59, 0xF3, 0x9A, 0x11},
    {0x02, 0x89, 0x62, 0xF6, 0x1B, 0x7B, 0xF8, 0x9E, 0xFC, 0x6B, 0x55, 0x1F,
     0x46, 0x67, 0xD9, 0x83},
    {0x28, 0xA7, 0x02, 0x3F, 0x45, 0x2E, 0x8F, 0x82, 0xBD, 0x4B, 0xF2, 0x8D,
     0x8C, 0x37, 0xC3, 0x5C},
    {0x15, 0x67, 0x27, 0xDC, 0x08, 0x78, 0x94, 0x4A, 0x02, 0x3C, 0x1F, 0xE0,
     0x3B, 0xAD, 0x6D, 0x93},
    {0xE1, 0x99, 0x21, 0x90, 0x54, 0x9F, 0x6E, 0xD5, 0x69, 0x6A, 0x2C, 0x05,
     0x6C, 0x31, 0x54, 0x10}};
PR_STATIC_ASSERT(PR_ARRAY_SIZE(kNistKnown) ==
                 kNistKeyLengthsCount * kNistPlaintextLengthsCount);

TEST_F(CmacAesTest, AesNistAligned) {
  for (unsigned int key_index = 0; key_index < kNistKeyLengthsCount;
       key_index++) {
    ScopedCMACContext ctx(CMAC_Create(CMAC_AES, kNistKeys[key_index],
                                      kNistKeyLengths[key_index]));
    ASSERT_NE(ctx, nullptr);

    for (unsigned int plaintext_index = 0;
         plaintext_index < kNistPlaintextLengthsCount; plaintext_index++) {
      CMAC_Begin(ctx.get());

      unsigned int known_index =
          (key_index * kNistPlaintextLengthsCount) + plaintext_index;
      CMAC_Update(ctx.get(), kNistPlaintext,
                  kNistPlaintextLengths[plaintext_index]);

      uint8_t output[AES_BLOCK_SIZE];
      CMAC_Finish(ctx.get(), output, NULL, AES_BLOCK_SIZE);

      ASSERT_TRUE(Compare(output, kNistKnown[known_index], AES_BLOCK_SIZE));
    }
  }
}

TEST_F(CmacAesTest, AesNistUnaligned) {
  for (unsigned int key_index = 0; key_index < kNistKeyLengthsCount;
       key_index++) {
    unsigned int key_length = kNistKeyLengths[key_index];
    ScopedCMACContext ctx(
        CMAC_Create(CMAC_AES, kNistKeys[key_index], key_length));
    ASSERT_NE(ctx, nullptr);

    // Skip the zero-length test.
    for (unsigned int plaintext_index = 1;
         plaintext_index < kNistPlaintextLengthsCount; plaintext_index++) {
      unsigned int known_index =
          (key_index * kNistPlaintextLengthsCount) + plaintext_index;
      unsigned int plaintext_length = kNistPlaintextLengths[plaintext_index];

      // Test all possible offsets and make sure that misaligned updates
      // produce the desired result. That is, do two updates:
      //  0      ... offset
      //  offset ... len - offset
      // and ensure the result is the same as doing one update.
      for (unsigned int offset = 1; offset < plaintext_length; offset++) {
        CMAC_Begin(ctx.get());

        CMAC_Update(ctx.get(), kNistPlaintext, offset);
        CMAC_Update(ctx.get(), kNistPlaintext + offset,
                    plaintext_length - offset);

        uint8_t output[AES_BLOCK_SIZE];
        CMAC_Finish(ctx.get(), output, NULL, AES_BLOCK_SIZE);

        ASSERT_TRUE(Compare(output, kNistKnown[known_index], AES_BLOCK_SIZE));
      }
    }
  }
}

TEST_F(CmacAesTest, AesNistTruncated) {
  for (unsigned int key_index = 0; key_index < kNistKeyLengthsCount;
       key_index++) {
    unsigned int key_length = kNistKeyLengths[key_index];
    ScopedCMACContext ctx(
        CMAC_Create(CMAC_AES, kNistKeys[key_index], key_length));
    ASSERT_TRUE(ctx != nullptr);

    // Skip the zero-length test.
    for (unsigned int plaintext_index = 1;
         plaintext_index < kNistPlaintextLengthsCount; plaintext_index++) {
      unsigned int known_index =
          (key_index * kNistPlaintextLengthsCount) + plaintext_index;
      unsigned int plaintext_length = kNistPlaintextLengths[plaintext_index];

      // Test truncated outputs to ensure that we always get the desired values.
      for (unsigned int out_len = 1; out_len < AES_BLOCK_SIZE; out_len++) {
        CMAC_Begin(ctx.get());

        CMAC_Update(ctx.get(), kNistPlaintext, plaintext_length);

        unsigned int actual_out_len = 0;
        uint8_t output[AES_BLOCK_SIZE];
        CMAC_Finish(ctx.get(), output, &actual_out_len, out_len);

        ASSERT_TRUE(actual_out_len == out_len);
        ASSERT_TRUE(Compare(output, kNistKnown[known_index], out_len));
      }
    }
  }
}