net/ntlm/ntlm.cc - chromium/src - Git at Google

 // Copyright 2017 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 "net/ntlm/ntlm.h"

 #include <string.h>

 #include "base/logging.h"
 #include "base/md5.h"
 #include "base/strings/utf_string_conversions.h"
 #include "net/base/net_string_util.h"
 #include "net/ntlm/ntlm_buffer_writer.h"
 #include "third_party/boringssl/src/include/openssl/des.h"
 #include "third_party/boringssl/src/include/openssl/hmac.h"
 #include "third_party/boringssl/src/include/openssl/md4.h"
 #include "third_party/boringssl/src/include/openssl/md5.h"

 namespace net {
 namespace ntlm {

 namespace {

 // Takes the parsed target info in |av_pairs| and performs the following
 // actions.
 //
 // 1) If a |TargetInfoAvId::kTimestamp| AvPair exists, |server_timestamp|
 //    is set to the payload.
 // 2) If |is_mic_enabled| is true, the existing |TargetInfoAvId::kFlags| AvPair
 //    will have the |TargetInfoAvFlags::kMicPresent| bit set. If an existing
 //    flags AvPair does not already exist, a new one is added with the value of
 //    |TargetInfoAvFlags::kMicPresent|.
 // 3) If |is_epa_enabled| is true, two new AvPair entries will be added to
 //    |av_pairs|. The first will be of type |TargetInfoAvId::kChannelBindings|
 //    and contains MD5(|channel_bindings|) as the payload. The second will be
 //    of type |TargetInfoAvId::kTargetName| and contains |spn| as a little
 //    endian UTF16 string.
 // 4) Sets |target_info_len| to the size of |av_pairs| when serialized into
 //    a payload.
 void UpdateTargetInfoAvPairs(bool is_mic_enabled,
                              bool is_epa_enabled,
                              const std::string& channel_bindings,
                              const std::string& spn,
                              std::vector<AvPair>* av_pairs,
                              uint64_t* server_timestamp,
                              size_t* target_info_len) {
   // Do a pass to update flags and calculate current length and
   // pull out the server timestamp if it is there.
   *server_timestamp = UINT64_MAX;
   *target_info_len = 0;

   bool need_flags_added = is_mic_enabled;
   for (AvPair& pair : *av_pairs) {
     *target_info_len += pair.avlen + kAvPairHeaderLen;
     switch (pair.avid) {
       case TargetInfoAvId::kFlags:
         // The parsing phase already set the payload to the |flags| field.
         if (is_mic_enabled) {
           pair.flags = pair.flags | TargetInfoAvFlags::kMicPresent;
         }

         need_flags_added = false;
         break;
       case TargetInfoAvId::kTimestamp:
         // The parsing phase already set the payload to the |timestamp| field.
         *server_timestamp = pair.timestamp;
         break;
       case TargetInfoAvId::kEol:
       case TargetInfoAvId::kChannelBindings:
       case TargetInfoAvId::kTargetName:
         // The terminator, |kEol|, should already have been removed from the
         // end of the list and would have been rejected if it has been inside
         // the list. Additionally |kChannelBindings| and |kTargetName| pairs
         // would have been rejected during the initial parsing. See
         // |NtlmBufferReader::ReadTargetInfo|.
         NOTREACHED();
         break;
       default:
         // Ignore entries we don't care about.
         break;
     }
   }

   if (need_flags_added) {
     DCHECK(is_mic_enabled);
     AvPair flags_pair(TargetInfoAvId::kFlags, sizeof(uint32_t));
     flags_pair.flags = TargetInfoAvFlags::kMicPresent;

     av_pairs->push_back(flags_pair);
     *target_info_len += kAvPairHeaderLen + flags_pair.avlen;
   }

   if (is_epa_enabled) {
     Buffer channel_bindings_hash(kChannelBindingsHashLen, 0);

     // Hash the channel bindings if they exist otherwise they remain zeros.
     if (!channel_bindings.empty()) {
       GenerateChannelBindingHashV2(channel_bindings, &channel_bindings_hash[0]);
     }

     av_pairs->emplace_back(TargetInfoAvId::kChannelBindings,
                            std::move(channel_bindings_hash));

     // Convert the SPN to little endian unicode.
     base::string16 spn16 = base::UTF8ToUTF16(spn);
     NtlmBufferWriter spn_writer(spn16.length() * 2);
     bool spn_writer_result =
         spn_writer.WriteUtf16String(spn16) && spn_writer.IsEndOfBuffer();
     DCHECK(spn_writer_result);

     av_pairs->emplace_back(TargetInfoAvId::kTargetName, spn_writer.Pass());

     // Add the length of the two new AV Pairs to the total length.
     *target_info_len +=
         (2 * kAvPairHeaderLen) + kChannelBindingsHashLen + (spn16.length() * 2);
   }

   // Add extra space for the terminator at the end.
   *target_info_len += kAvPairHeaderLen;
 }

 Buffer WriteUpdatedTargetInfo(const std::vector<AvPair>& av_pairs,
                               size_t updated_target_info_len) {
   bool result = true;
   NtlmBufferWriter writer(updated_target_info_len);
   for (const AvPair& pair : av_pairs) {
     result = writer.WriteAvPair(pair);
     DCHECK(result);
   }

   result = writer.WriteAvPairTerminator() && writer.IsEndOfBuffer();
   DCHECK(result);
   return writer.Pass();
 }

 // Reads 7 bytes (56 bits) from |key_56| and writes them into 8 bytes of
 // |key_64| with 7 bits in every byte. The least significant bits are
 // undefined and a subsequent operation will set those bits with a parity bit.
 // |key_56| must contain 7 bytes.
 // |key_64| must contain 8 bytes.
 void Splay56To64(const uint8_t* key_56, uint8_t* key_64) {
   key_64[0] = key_56[0];
   key_64[1] = key_56[0] << 7 | key_56[1] >> 1;
   key_64[2] = key_56[1] << 6 | key_56[2] >> 2;
   key_64[3] = key_56[2] << 5 | key_56[3] >> 3;
   key_64[4] = key_56[3] << 4 | key_56[4] >> 4;
   key_64[5] = key_56[4] << 3 | key_56[5] >> 5;
   key_64[6] = key_56[5] << 2 | key_56[6] >> 6;
   key_64[7] = key_56[6] << 1;
 }

 }  // namespace

 void Create3DesKeysFromNtlmHash(const uint8_t* ntlm_hash, uint8_t* keys) {
   // Put the first 112 bits from |ntlm_hash| into the first 16 bytes of
   // |keys|.
   Splay56To64(ntlm_hash, keys);
   Splay56To64(ntlm_hash + 7, keys + 8);

   // Put the next 2x 7 bits in bytes 16 and 17 of |keys|, then
   // the last 2 bits in byte 18, then zero pad the rest of the final key.
   keys[16] = ntlm_hash[14];
   keys[17] = ntlm_hash[14] << 7 | ntlm_hash[15] >> 1;
   keys[18] = ntlm_hash[15] << 6;
   memset(keys + 19, 0, 5);
 }

 void GenerateNtlmHashV1(const base::string16& password, uint8_t* hash) {
   size_t length = password.length() * 2;
   NtlmBufferWriter writer(length);

   // The writer will handle the big endian case if necessary.
   bool result = writer.WriteUtf16String(password) && writer.IsEndOfBuffer();
   DCHECK(result);

   MD4(writer.GetBuffer().data(), writer.GetLength(), hash);
 }

 void GenerateResponseDesl(const uint8_t* hash,
                           const uint8_t* challenge,
                           uint8_t* response) {
   constexpr size_t block_count = 3;
   constexpr size_t block_size = sizeof(DES_cblock);
   static_assert(kChallengeLen == block_size,
                 "kChallengeLen must equal block_size");
   static_assert(kResponseLenV1 == block_count * block_size,
                 "kResponseLenV1 must equal block_count * block_size");

   const DES_cblock* challenge_block =
       reinterpret_cast<const DES_cblock*>(challenge);
   uint8_t keys[block_count * block_size];

   // Map the NTLM hash to three 8 byte DES keys, with 7 bits of the key in each
   // byte and the least significant bit set with odd parity. Then encrypt the
   // 8 byte challenge with each of the three keys. This produces three 8 byte
   // encrypted blocks into |response|.
   Create3DesKeysFromNtlmHash(hash, keys);
   for (size_t ix = 0; ix < block_count * block_size; ix += block_size) {
     DES_cblock* key_block = reinterpret_cast<DES_cblock*>(keys + ix);
     DES_cblock* response_block = reinterpret_cast<DES_cblock*>(response + ix);

     DES_key_schedule key_schedule;
     DES_set_odd_parity(key_block);
     DES_set_key(key_block, &key_schedule);
     DES_ecb_encrypt(challenge_block, response_block, &key_schedule,
                     DES_ENCRYPT);
   }
 }

 void GenerateNtlmResponseV1(const base::string16& password,
                             const uint8_t* challenge,
                             uint8_t* ntlm_response) {
   uint8_t ntlm_hash[kNtlmHashLen];
   GenerateNtlmHashV1(password, ntlm_hash);
   GenerateResponseDesl(ntlm_hash, challenge, ntlm_response);
 }

 void GenerateResponsesV1(const base::string16& password,
                          const uint8_t* server_challenge,
                          uint8_t* lm_response,
                          uint8_t* ntlm_response) {
   GenerateNtlmResponseV1(password, server_challenge, ntlm_response);

   // In NTLM v1 (with LMv1 disabled), the lm_response and ntlm_response are the
   // same. So just copy the ntlm_response into the lm_response.
   memcpy(lm_response, ntlm_response, kResponseLenV1);
 }

 void GenerateLMResponseV1WithSessionSecurity(const uint8_t* client_challenge,
                                              uint8_t* lm_response) {
   // In NTLM v1 with Session Security (aka NTLM2) the lm_response is 8 bytes of
   // client challenge and 16 bytes of zeros. (See 3.3.1)
   memcpy(lm_response, client_challenge, kChallengeLen);
   memset(lm_response + kChallengeLen, 0, kResponseLenV1 - kChallengeLen);
 }

 void GenerateSessionHashV1WithSessionSecurity(const uint8_t* server_challenge,
                                               const uint8_t* client_challenge,
                                               uint8_t* session_hash) {
   MD5_CTX ctx;
   MD5_Init(&ctx);
   MD5_Update(&ctx, server_challenge, kChallengeLen);
   MD5_Update(&ctx, client_challenge, kChallengeLen);
   MD5_Final(session_hash, &ctx);
 }

 void GenerateNtlmResponseV1WithSessionSecurity(const base::string16& password,
                                                const uint8_t* server_challenge,
                                                const uint8_t* client_challenge,
                                                uint8_t* ntlm_response) {
   // Generate the NTLMv1 Hash.
   uint8_t ntlm_hash[kNtlmHashLen];
   GenerateNtlmHashV1(password, ntlm_hash);

   // Generate the NTLMv1 Session Hash.
   uint8_t session_hash[kNtlmHashLen];
   GenerateSessionHashV1WithSessionSecurity(server_challenge, client_challenge,
                                            session_hash);

   // Only the first 8 bytes of |session_hash| are actually used.
   GenerateResponseDesl(ntlm_hash, session_hash, ntlm_response);
 }

 void GenerateResponsesV1WithSessionSecurity(const base::string16& password,
                                             const uint8_t* server_challenge,
                                             const uint8_t* client_challenge,
                                             uint8_t* lm_response,
                                             uint8_t* ntlm_response) {
   GenerateLMResponseV1WithSessionSecurity(client_challenge, lm_response);
   GenerateNtlmResponseV1WithSessionSecurity(password, server_challenge,
                                             client_challenge, ntlm_response);
 }

 void GenerateNtlmHashV2(const base::string16& domain,
                         const base::string16& username,
                         const base::string16& password,
                         uint8_t* v2_hash) {
   // NOTE: According to [MS-NLMP] Section 3.3.2 only the username and not the
   // domain is uppercased.
   base::string16 upper_username;
   bool result = ToUpper(username, &upper_username);
   DCHECK(result);

   uint8_t v1_hash[kNtlmHashLen];
   GenerateNtlmHashV1(password, v1_hash);
   NtlmBufferWriter input_writer((upper_username.length() + domain.length()) *
                                 2);
   bool writer_result = input_writer.WriteUtf16String(upper_username) &&
                        input_writer.WriteUtf16String(domain) &&
                        input_writer.IsEndOfBuffer();
   DCHECK(writer_result);

   unsigned int outlen = kNtlmHashLen;
   v2_hash =
       HMAC(EVP_md5(), v1_hash, sizeof(v1_hash), input_writer.GetBuffer().data(),
            input_writer.GetLength(), v2_hash, &outlen);
   DCHECK_NE(nullptr, v2_hash);
   DCHECK_EQ(sizeof(v1_hash), outlen);
 }

 Buffer GenerateProofInputV2(uint64_t timestamp,
                             const uint8_t* client_challenge) {
   NtlmBufferWriter writer(kProofInputLenV2);
   bool result = writer.WriteUInt16(kProofInputVersionV2) &&
                 writer.WriteZeros(6) && writer.WriteUInt64(timestamp) &&
                 writer.WriteBytes(client_challenge, kChallengeLen) &&
                 writer.WriteZeros(4) && writer.IsEndOfBuffer();

   DCHECK(result);
   return writer.Pass();
 }

 void GenerateNtlmProofV2(const uint8_t* v2_hash,
                          const uint8_t* server_challenge,
                          const Buffer& v2_input,
                          const Buffer& target_info,
                          uint8_t* v2_proof) {
   DCHECK_EQ(kProofInputLenV2, v2_input.size());

   bssl::ScopedHMAC_CTX ctx;
   HMAC_Init_ex(ctx.get(), v2_hash, kNtlmHashLen, EVP_md5(), NULL);
   DCHECK_EQ(kNtlmProofLenV2, HMAC_size(ctx.get()));
   HMAC_Update(ctx.get(), server_challenge, kChallengeLen);
   HMAC_Update(ctx.get(), v2_input.data(), v2_input.size());
   HMAC_Update(ctx.get(), target_info.data(), target_info.size());
   const uint32_t zero = 0;
   HMAC_Update(ctx.get(), reinterpret_cast<const uint8_t*>(&zero),
               sizeof(uint32_t));
   HMAC_Final(ctx.get(), v2_proof, nullptr);
 }

 void GenerateSessionBaseKeyV2(const uint8_t* v2_hash,
                               const uint8_t* v2_proof,
                               uint8_t* session_key) {
   unsigned int outlen = kSessionKeyLenV2;
   session_key = HMAC(EVP_md5(), v2_hash, kNtlmHashLen, v2_proof,
                      kNtlmProofLenV2, session_key, &outlen);
   DCHECK_NE(nullptr, session_key);
   DCHECK_EQ(kSessionKeyLenV2, outlen);
 }

 void GenerateChannelBindingHashV2(const std::string& channel_bindings,
                                   uint8_t* channel_bindings_hash) {
   NtlmBufferWriter writer(kEpaUnhashedStructHeaderLen);
   bool result = writer.WriteZeros(16) &&
                 writer.WriteUInt32(channel_bindings.length()) &&
                 writer.IsEndOfBuffer();
   DCHECK(result);

   MD5_CTX ctx;
   MD5_Init(&ctx);
   MD5_Update(&ctx, writer.GetBuffer().data(), writer.GetBuffer().size());
   MD5_Update(&ctx, channel_bindings.data(), channel_bindings.size());
   MD5_Final(channel_bindings_hash, &ctx);
 }

 void GenerateMicV2(const uint8_t* session_key,
                    const Buffer& negotiate_msg,
                    const Buffer& challenge_msg,
                    const Buffer& authenticate_msg,
                    uint8_t* mic) {
   bssl::ScopedHMAC_CTX ctx;
   HMAC_Init_ex(ctx.get(), session_key, kNtlmHashLen, EVP_md5(), NULL);
   DCHECK_EQ(kMicLenV2, HMAC_size(ctx.get()));
   HMAC_Update(ctx.get(), negotiate_msg.data(), negotiate_msg.size());
   HMAC_Update(ctx.get(), challenge_msg.data(), challenge_msg.size());
   HMAC_Update(ctx.get(), authenticate_msg.data(), authenticate_msg.size());
   HMAC_Final(ctx.get(), mic, nullptr);
 }

 NET_EXPORT_PRIVATE Buffer
 GenerateUpdatedTargetInfo(bool is_mic_enabled,
                           bool is_epa_enabled,
                           const std::string& channel_bindings,
                           const std::string& spn,
                           const std::vector<AvPair>& av_pairs,
                           uint64_t* server_timestamp) {
   size_t updated_target_info_len = 0;
   std::vector<AvPair> updated_av_pairs(av_pairs);
   UpdateTargetInfoAvPairs(is_mic_enabled, is_epa_enabled, channel_bindings, spn,
                           &updated_av_pairs, server_timestamp,
                           &updated_target_info_len);
   return WriteUpdatedTargetInfo(updated_av_pairs, updated_target_info_len);
 }

 }  // namespace ntlm
 }  // namespace net
	// Copyright 2017 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 "net/ntlm/ntlm.h"

	#include <string.h>

	#include "base/logging.h"
	#include "base/md5.h"
	#include "base/strings/utf_string_conversions.h"
	#include "net/base/net_string_util.h"
	#include "net/ntlm/ntlm_buffer_writer.h"
	#include "third_party/boringssl/src/include/openssl/des.h"
	#include "third_party/boringssl/src/include/openssl/hmac.h"
	#include "third_party/boringssl/src/include/openssl/md4.h"
	#include "third_party/boringssl/src/include/openssl/md5.h"

	namespace net {
	namespace ntlm {

	namespace {

	// Takes the parsed target info in \|av_pairs\| and performs the following
	// actions.
	//
	// 1) If a \|TargetInfoAvId::kTimestamp\| AvPair exists, \|server_timestamp\|
	// is set to the payload.
	// 2) If \|is_mic_enabled\| is true, the existing \|TargetInfoAvId::kFlags\| AvPair
	// will have the \|TargetInfoAvFlags::kMicPresent\| bit set. If an existing
	// flags AvPair does not already exist, a new one is added with the value of
	// \|TargetInfoAvFlags::kMicPresent\|.
	// 3) If \|is_epa_enabled\| is true, two new AvPair entries will be added to
	// \|av_pairs\|. The first will be of type \|TargetInfoAvId::kChannelBindings\|
	// and contains MD5(\|channel_bindings\|) as the payload. The second will be
	// of type \|TargetInfoAvId::kTargetName\| and contains \|spn\| as a little
	// endian UTF16 string.
	// 4) Sets \|target_info_len\| to the size of \|av_pairs\| when serialized into
	// a payload.
	void UpdateTargetInfoAvPairs(bool is_mic_enabled,
	bool is_epa_enabled,
	const std::string& channel_bindings,
	const std::string& spn,
	std::vector<AvPair>* av_pairs,
	uint64_t* server_timestamp,
	size_t* target_info_len) {
	// Do a pass to update flags and calculate current length and
	// pull out the server timestamp if it is there.
	*server_timestamp = UINT64_MAX;
	*target_info_len = 0;

	bool need_flags_added = is_mic_enabled;
	for (AvPair& pair : *av_pairs) {
	*target_info_len += pair.avlen + kAvPairHeaderLen;
	switch (pair.avid) {
	case TargetInfoAvId::kFlags:
	// The parsing phase already set the payload to the \|flags\| field.
	if (is_mic_enabled) {
	pair.flags = pair.flags \| TargetInfoAvFlags::kMicPresent;
	}

	need_flags_added = false;
	break;
	case TargetInfoAvId::kTimestamp:
	// The parsing phase already set the payload to the \|timestamp\| field.
	*server_timestamp = pair.timestamp;
	break;
	case TargetInfoAvId::kEol:
	case TargetInfoAvId::kChannelBindings:
	case TargetInfoAvId::kTargetName:
	// The terminator, \|kEol\|, should already have been removed from the
	// end of the list and would have been rejected if it has been inside
	// the list. Additionally \|kChannelBindings\| and \|kTargetName\| pairs
	// would have been rejected during the initial parsing. See
	// \|NtlmBufferReader::ReadTargetInfo\|.
	NOTREACHED();
	break;
	default:
	// Ignore entries we don't care about.
	break;
	}
	}

	if (need_flags_added) {
	DCHECK(is_mic_enabled);
	AvPair flags_pair(TargetInfoAvId::kFlags, sizeof(uint32_t));
	flags_pair.flags = TargetInfoAvFlags::kMicPresent;

	av_pairs->push_back(flags_pair);
	*target_info_len += kAvPairHeaderLen + flags_pair.avlen;
	}

	if (is_epa_enabled) {
	Buffer channel_bindings_hash(kChannelBindingsHashLen, 0);

	// Hash the channel bindings if they exist otherwise they remain zeros.
	if (!channel_bindings.empty()) {
	GenerateChannelBindingHashV2(channel_bindings, &channel_bindings_hash[0]);
	}

	av_pairs->emplace_back(TargetInfoAvId::kChannelBindings,
	std::move(channel_bindings_hash));

	// Convert the SPN to little endian unicode.
	base::string16 spn16 = base::UTF8ToUTF16(spn);
	NtlmBufferWriter spn_writer(spn16.length() * 2);
	bool spn_writer_result =
	spn_writer.WriteUtf16String(spn16) && spn_writer.IsEndOfBuffer();
	DCHECK(spn_writer_result);

	av_pairs->emplace_back(TargetInfoAvId::kTargetName, spn_writer.Pass());

	// Add the length of the two new AV Pairs to the total length.
	*target_info_len +=
	(2 * kAvPairHeaderLen) + kChannelBindingsHashLen + (spn16.length() * 2);
	}

	// Add extra space for the terminator at the end.
	*target_info_len += kAvPairHeaderLen;
	}

	Buffer WriteUpdatedTargetInfo(const std::vector<AvPair>& av_pairs,
	size_t updated_target_info_len) {
	bool result = true;
	NtlmBufferWriter writer(updated_target_info_len);
	for (const AvPair& pair : av_pairs) {
	result = writer.WriteAvPair(pair);
	DCHECK(result);
	}

	result = writer.WriteAvPairTerminator() && writer.IsEndOfBuffer();
	DCHECK(result);
	return writer.Pass();
	}

	// Reads 7 bytes (56 bits) from \|key_56\| and writes them into 8 bytes of
	// \|key_64\| with 7 bits in every byte. The least significant bits are
	// undefined and a subsequent operation will set those bits with a parity bit.
	// \|key_56\| must contain 7 bytes.
	// \|key_64\| must contain 8 bytes.
	void Splay56To64(const uint8_t* key_56, uint8_t* key_64) {
	key_64[0] = key_56[0];
	key_64[1] = key_56[0] << 7 \| key_56[1] >> 1;
	key_64[2] = key_56[1] << 6 \| key_56[2] >> 2;
	key_64[3] = key_56[2] << 5 \| key_56[3] >> 3;
	key_64[4] = key_56[3] << 4 \| key_56[4] >> 4;
	key_64[5] = key_56[4] << 3 \| key_56[5] >> 5;
	key_64[6] = key_56[5] << 2 \| key_56[6] >> 6;
	key_64[7] = key_56[6] << 1;
	}

	} // namespace

	void Create3DesKeysFromNtlmHash(const uint8_t* ntlm_hash, uint8_t* keys) {
	// Put the first 112 bits from \|ntlm_hash\| into the first 16 bytes of
	// \|keys\|.
	Splay56To64(ntlm_hash, keys);
	Splay56To64(ntlm_hash + 7, keys + 8);

	// Put the next 2x 7 bits in bytes 16 and 17 of \|keys\|, then
	// the last 2 bits in byte 18, then zero pad the rest of the final key.
	keys[16] = ntlm_hash[14];
	keys[17] = ntlm_hash[14] << 7 \| ntlm_hash[15] >> 1;
	keys[18] = ntlm_hash[15] << 6;
	memset(keys + 19, 0, 5);
	}

	void GenerateNtlmHashV1(const base::string16& password, uint8_t* hash) {
	size_t length = password.length() * 2;
	NtlmBufferWriter writer(length);

	// The writer will handle the big endian case if necessary.
	bool result = writer.WriteUtf16String(password) && writer.IsEndOfBuffer();
	DCHECK(result);

	MD4(writer.GetBuffer().data(), writer.GetLength(), hash);
	}

	void GenerateResponseDesl(const uint8_t* hash,
	const uint8_t* challenge,
	uint8_t* response) {
	constexpr size_t block_count = 3;
	constexpr size_t block_size = sizeof(DES_cblock);
	static_assert(kChallengeLen == block_size,
	"kChallengeLen must equal block_size");
	static_assert(kResponseLenV1 == block_count * block_size,
	"kResponseLenV1 must equal block_count * block_size");

	const DES_cblock* challenge_block =
	reinterpret_cast<const DES_cblock*>(challenge);
	uint8_t keys[block_count * block_size];

	// Map the NTLM hash to three 8 byte DES keys, with 7 bits of the key in each
	// byte and the least significant bit set with odd parity. Then encrypt the
	// 8 byte challenge with each of the three keys. This produces three 8 byte
	// encrypted blocks into \|response\|.
	Create3DesKeysFromNtlmHash(hash, keys);
	for (size_t ix = 0; ix < block_count * block_size; ix += block_size) {
	DES_cblock* key_block = reinterpret_cast<DES_cblock*>(keys + ix);
	DES_cblock* response_block = reinterpret_cast<DES_cblock*>(response + ix);

	DES_key_schedule key_schedule;
	DES_set_odd_parity(key_block);
	DES_set_key(key_block, &key_schedule);
	DES_ecb_encrypt(challenge_block, response_block, &key_schedule,
	DES_ENCRYPT);
	}
	}

	void GenerateNtlmResponseV1(const base::string16& password,
	const uint8_t* challenge,
	uint8_t* ntlm_response) {
	uint8_t ntlm_hash[kNtlmHashLen];
	GenerateNtlmHashV1(password, ntlm_hash);
	GenerateResponseDesl(ntlm_hash, challenge, ntlm_response);
	}

	void GenerateResponsesV1(const base::string16& password,
	const uint8_t* server_challenge,
	uint8_t* lm_response,
	uint8_t* ntlm_response) {
	GenerateNtlmResponseV1(password, server_challenge, ntlm_response);

	// In NTLM v1 (with LMv1 disabled), the lm_response and ntlm_response are the
	// same. So just copy the ntlm_response into the lm_response.
	memcpy(lm_response, ntlm_response, kResponseLenV1);
	}

	void GenerateLMResponseV1WithSessionSecurity(const uint8_t* client_challenge,
	uint8_t* lm_response) {
	// In NTLM v1 with Session Security (aka NTLM2) the lm_response is 8 bytes of
	// client challenge and 16 bytes of zeros. (See 3.3.1)
	memcpy(lm_response, client_challenge, kChallengeLen);
	memset(lm_response + kChallengeLen, 0, kResponseLenV1 - kChallengeLen);
	}

	void GenerateSessionHashV1WithSessionSecurity(const uint8_t* server_challenge,
	const uint8_t* client_challenge,
	uint8_t* session_hash) {
	MD5_CTX ctx;
	MD5_Init(&ctx);
	MD5_Update(&ctx, server_challenge, kChallengeLen);
	MD5_Update(&ctx, client_challenge, kChallengeLen);
	MD5_Final(session_hash, &ctx);
	}

	void GenerateNtlmResponseV1WithSessionSecurity(const base::string16& password,
	const uint8_t* server_challenge,
	const uint8_t* client_challenge,
	uint8_t* ntlm_response) {
	// Generate the NTLMv1 Hash.
	uint8_t ntlm_hash[kNtlmHashLen];
	GenerateNtlmHashV1(password, ntlm_hash);

	// Generate the NTLMv1 Session Hash.
	uint8_t session_hash[kNtlmHashLen];
	GenerateSessionHashV1WithSessionSecurity(server_challenge, client_challenge,
	session_hash);

	// Only the first 8 bytes of \|session_hash\| are actually used.
	GenerateResponseDesl(ntlm_hash, session_hash, ntlm_response);
	}

	void GenerateResponsesV1WithSessionSecurity(const base::string16& password,
	const uint8_t* server_challenge,
	const uint8_t* client_challenge,
	uint8_t* lm_response,
	uint8_t* ntlm_response) {
	GenerateLMResponseV1WithSessionSecurity(client_challenge, lm_response);
	GenerateNtlmResponseV1WithSessionSecurity(password, server_challenge,
	client_challenge, ntlm_response);
	}

	void GenerateNtlmHashV2(const base::string16& domain,
	const base::string16& username,
	const base::string16& password,
	uint8_t* v2_hash) {
	// NOTE: According to [MS-NLMP] Section 3.3.2 only the username and not the
	// domain is uppercased.
	base::string16 upper_username;
	bool result = ToUpper(username, &upper_username);
	DCHECK(result);

	uint8_t v1_hash[kNtlmHashLen];
	GenerateNtlmHashV1(password, v1_hash);
	NtlmBufferWriter input_writer((upper_username.length() + domain.length()) *
	2);
	bool writer_result = input_writer.WriteUtf16String(upper_username) &&
	input_writer.WriteUtf16String(domain) &&
	input_writer.IsEndOfBuffer();
	DCHECK(writer_result);

	unsigned int outlen = kNtlmHashLen;
	v2_hash =
	HMAC(EVP_md5(), v1_hash, sizeof(v1_hash), input_writer.GetBuffer().data(),
	input_writer.GetLength(), v2_hash, &outlen);
	DCHECK_NE(nullptr, v2_hash);
	DCHECK_EQ(sizeof(v1_hash), outlen);
	}

	Buffer GenerateProofInputV2(uint64_t timestamp,
	const uint8_t* client_challenge) {
	NtlmBufferWriter writer(kProofInputLenV2);
	bool result = writer.WriteUInt16(kProofInputVersionV2) &&
	writer.WriteZeros(6) && writer.WriteUInt64(timestamp) &&
	writer.WriteBytes(client_challenge, kChallengeLen) &&
	writer.WriteZeros(4) && writer.IsEndOfBuffer();

	DCHECK(result);
	return writer.Pass();
	}

	void GenerateNtlmProofV2(const uint8_t* v2_hash,
	const uint8_t* server_challenge,
	const Buffer& v2_input,
	const Buffer& target_info,
	uint8_t* v2_proof) {
	DCHECK_EQ(kProofInputLenV2, v2_input.size());

	bssl::ScopedHMAC_CTX ctx;
	HMAC_Init_ex(ctx.get(), v2_hash, kNtlmHashLen, EVP_md5(), NULL);
	DCHECK_EQ(kNtlmProofLenV2, HMAC_size(ctx.get()));
	HMAC_Update(ctx.get(), server_challenge, kChallengeLen);
	HMAC_Update(ctx.get(), v2_input.data(), v2_input.size());
	HMAC_Update(ctx.get(), target_info.data(), target_info.size());
	const uint32_t zero = 0;
	HMAC_Update(ctx.get(), reinterpret_cast<const uint8_t*>(&zero),
	sizeof(uint32_t));
	HMAC_Final(ctx.get(), v2_proof, nullptr);
	}

	void GenerateSessionBaseKeyV2(const uint8_t* v2_hash,
	const uint8_t* v2_proof,
	uint8_t* session_key) {
	unsigned int outlen = kSessionKeyLenV2;
	session_key = HMAC(EVP_md5(), v2_hash, kNtlmHashLen, v2_proof,
	kNtlmProofLenV2, session_key, &outlen);
	DCHECK_NE(nullptr, session_key);
	DCHECK_EQ(kSessionKeyLenV2, outlen);
	}

	void GenerateChannelBindingHashV2(const std::string& channel_bindings,
	uint8_t* channel_bindings_hash) {
	NtlmBufferWriter writer(kEpaUnhashedStructHeaderLen);
	bool result = writer.WriteZeros(16) &&
	writer.WriteUInt32(channel_bindings.length()) &&
	writer.IsEndOfBuffer();
	DCHECK(result);

	MD5_CTX ctx;
	MD5_Init(&ctx);
	MD5_Update(&ctx, writer.GetBuffer().data(), writer.GetBuffer().size());
	MD5_Update(&ctx, channel_bindings.data(), channel_bindings.size());
	MD5_Final(channel_bindings_hash, &ctx);
	}

	void GenerateMicV2(const uint8_t* session_key,
	const Buffer& negotiate_msg,
	const Buffer& challenge_msg,
	const Buffer& authenticate_msg,
	uint8_t* mic) {
	bssl::ScopedHMAC_CTX ctx;
	HMAC_Init_ex(ctx.get(), session_key, kNtlmHashLen, EVP_md5(), NULL);
	DCHECK_EQ(kMicLenV2, HMAC_size(ctx.get()));
	HMAC_Update(ctx.get(), negotiate_msg.data(), negotiate_msg.size());
	HMAC_Update(ctx.get(), challenge_msg.data(), challenge_msg.size());
	HMAC_Update(ctx.get(), authenticate_msg.data(), authenticate_msg.size());
	HMAC_Final(ctx.get(), mic, nullptr);
	}

	NET_EXPORT_PRIVATE Buffer
	GenerateUpdatedTargetInfo(bool is_mic_enabled,
	bool is_epa_enabled,
	const std::string& channel_bindings,
	const std::string& spn,
	const std::vector<AvPair>& av_pairs,
	uint64_t* server_timestamp) {
	size_t updated_target_info_len = 0;
	std::vector<AvPair> updated_av_pairs(av_pairs);
	UpdateTargetInfoAvPairs(is_mic_enabled, is_epa_enabled, channel_bindings, spn,
	&updated_av_pairs, server_timestamp,
	&updated_target_info_len);
	return WriteUpdatedTargetInfo(updated_av_pairs, updated_target_info_len);
	}

	} // namespace ntlm
	} // namespace net