SERVER-28052 Make SHA1Hash a full fledged class

(cherry picked from commit 71ce59a2648185c8e1ccd5b3a1af6ff05dbac7d7)
(cherry picked from commit 2e686c169d07ed06530aa650ced310ee7b1adfc6)

10 files changed, 377 insertions, 301 deletions

diff --git a/src/mongo/crypto/SConscript b/src/mongo/crypto/SConscript
index 9013c70b207..5b8ed85a684 100644
--- a/src/mongo/crypto/SConscript
+++ b/src/mongo/crypto/SConscript
@@ -8,22 +8,32 @@ env.SConscript(
     ],
 )
 
+env.Library('sha1_block',
+    source=[
+        'sha1_block.cpp'
+    ],
+    LIBDEPS=[
+        '$BUILD_DIR/mongo/base',
+    ])
+
 env.Library(
-    target='crypto_tom',
+    target='sha1_block_tom',
     source=[
-        'crypto_tom.cpp'
+        'sha1_block_tom.cpp'
     ],
     LIBDEPS=[
             '$BUILD_DIR/mongo/base',
+            'sha1_block',
             'tom/tomcrypt'
     ])
 
-env.Library('crypto_openssl',
+env.Library('sha1_block_openssl',
     source=[
-        'crypto_openssl.cpp'
+        'sha1_block_openssl.cpp'
     ],
     LIBDEPS=[
         '$BUILD_DIR/mongo/base',
+        'sha1_block',
     ])
 
 env.Library('scramauth',
@@ -31,8 +41,8 @@ env.Library('scramauth',
             LIBDEPS=['$BUILD_DIR/mongo/base',
                      '$BUILD_DIR/mongo/base/secure_allocator',
                      '$BUILD_DIR/mongo/util/secure_zero_memory',
-                     'crypto_${MONGO_CRYPTO}'])
+                     'sha1_block_${MONGO_CRYPTO}'])
 
-env.CppUnitTest('crypto_test',
-                ['crypto_test.cpp'],
-                LIBDEPS=['crypto_${MONGO_CRYPTO}'])
+env.CppUnitTest('sha1_block_test',
+                ['sha1_block_test.cpp'],
+                LIBDEPS=['sha1_block_${MONGO_CRYPTO}'])
diff --git a/src/mongo/crypto/crypto.h b/src/mongo/crypto/crypto.h
deleted file mode 100644
index 1f010980078..00000000000
--- a/src/mongo/crypto/crypto.h
+++ /dev/null
@@ -1,53 +0,0 @@
-/**
-*    Copyright (C) 2014 10gen Inc.
-*
-*    This program is free software: you can redistribute it and/or  modify
-*    it under the terms of the GNU Affero General Public License, version 3,
-*    as published by the Free Software Foundation.
-*
-*    This program is distributed in the hope that it will be useful,
-*    but WITHOUT ANY WARRANTY; without even the implied warranty of
-*    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-*    GNU Affero General Public License for more details.
-*
-*    You should have received a copy of the GNU Affero General Public License
-*    along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*
-*    As a special exception, the copyright holders give permission to link the
-*    code of portions of this program with the OpenSSL library under certain
-*    conditions as described in each individual source file and distribute
-*    linked combinations including the program with the OpenSSL library. You
-*    must comply with the GNU Affero General Public License in all respects for
-*    all of the code used other than as permitted herein. If you modify file(s)
-*    with this exception, you may extend this exception to your version of the
-*    file(s), but you are not obligated to do so. If you do not wish to do so,
-*    delete this exception statement from your version. If you delete this
-*    exception statement from all source files in the program, then also delete
-*    it in the license file.
-*/
-
-#pragma once
-
-#include <array>
-#include <cstddef>
-
-namespace mongo {
-// Storage container for a SHA1 hash
-using SHA1Hash = std::array<std::uint8_t, 20>;
-
-namespace crypto {
-/*
- * Computes a SHA-1 hash of 'input'.
- */
-SHA1Hash sha1(const unsigned char* input, const size_t inputLen);
-
-/*
- * Computes a HMAC SHA-1 keyed hash of 'input' using the key 'key'
- */
-SHA1Hash hmacSha1(const unsigned char* key,
-                  const size_t keyLen,
-                  const unsigned char* input,
-                  const size_t inputLen);
-
-}  // namespace crypto
-}  // namespace mongo
diff --git a/src/mongo/crypto/mechanism_scram.cpp b/src/mongo/crypto/mechanism_scram.cpp
index 5d1cb784011..b4a543c6a54 100644
--- a/src/mongo/crypto/mechanism_scram.cpp
+++ b/src/mongo/crypto/mechanism_scram.cpp
@@ -32,7 +32,6 @@
 
 #include <vector>
 
-#include "mongo/crypto/crypto.h"
 #include "mongo/platform/random.h"
 #include "mongo/util/base64.h"
 #include "mongo/util/secure_zero_memory.h"
@@ -67,18 +66,14 @@ bool consttimeMemEqual(volatile const unsigned char* s1,  // NOLINT - using vola
 }
 }  // namespace
 
-std::string hashToBase64(const SecureHandle<SHA1Hash>& hash) {
-    return base64::encode(reinterpret_cast<const char*>(hash->data()), hash->size());
-}
-
 // Compute the SCRAM step Hi() as defined in RFC5802
-static SHA1Hash HMACIteration(const unsigned char input[],
-                              size_t inputLen,
-                              const unsigned char salt[],
-                              size_t saltLen,
-                              unsigned int iterationCount) {
-    SHA1Hash output;
-    SHA1Hash intermediateDigest;
+static SHA1Block HMACIteration(const unsigned char input[],
+                               size_t inputLen,
+                               const unsigned char salt[],
+                               size_t saltLen,
+                               unsigned int iterationCount) {
+    SHA1Block output;
+    SHA1Block intermediateDigest;
     // Reserve a 20 byte block for the initial key. We use 16 byte salts, and must reserve an extra
     // 4 bytes for a suffix mandated by RFC5802.
     std::array<std::uint8_t, 20> startKey;
@@ -92,25 +87,23 @@ static SHA1Hash HMACIteration(const unsigned char input[],
     startKey[saltLen + 3] = 1;
 
     // U1 = HMAC(input, salt + 0001)
-    output = crypto::hmacSha1(input, inputLen, startKey.data(), startKey.size());
+    output = SHA1Block::computeHmac(input, inputLen, startKey.data(), startKey.size());
     intermediateDigest = output;
 
     // intermediateDigest contains Ui and output contains the accumulated XOR:ed result
     for (size_t i = 2; i <= iterationCount; i++) {
-        intermediateDigest =
-            crypto::hmacSha1(input, inputLen, intermediateDigest.data(), intermediateDigest.size());
-        for (size_t k = 0; k < output.size(); k++) {
-            output[k] ^= intermediateDigest[k];
-        }
+        intermediateDigest = SHA1Block::computeHmac(
+            input, inputLen, intermediateDigest.data(), intermediateDigest.size());
+        output.xorInline(intermediateDigest);
     }
 
     return output;
 }
 
 // Iterate the hash function to generate SaltedPassword
-SHA1Hash generateSaltedPassword(const SCRAMPresecrets& presecrets) {
+SHA1Block generateSaltedPassword(const SCRAMPresecrets& presecrets) {
     // saltedPassword = Hi(hashedPassword, salt)
-    SHA1Hash saltedPassword =
+    SHA1Block saltedPassword =
         HMACIteration(reinterpret_cast<const unsigned char*>(presecrets.hashedPassword.c_str()),
                       presecrets.hashedPassword.size(),
                       presecrets.salt.data(),
@@ -121,30 +114,30 @@ SHA1Hash generateSaltedPassword(const SCRAMPresecrets& presecrets) {
 }
 
 SCRAMSecrets generateSecrets(const SCRAMPresecrets& presecrets) {
-    SHA1Hash saltedPassword = generateSaltedPassword(presecrets);
+    SHA1Block saltedPassword = generateSaltedPassword(presecrets);
     return generateSecrets(saltedPassword);
 }
 
-SCRAMSecrets generateSecrets(const SHA1Hash& saltedPassword) {
+SCRAMSecrets generateSecrets(const SHA1Block& saltedPassword) {
     SCRAMSecrets credentials;
 
     // ClientKey := HMAC(saltedPassword, "Client Key")
     credentials.clientKey =
-        crypto::hmacSha1(saltedPassword.data(),
-                         saltedPassword.size(),
-                         reinterpret_cast<const unsigned char*>(clientKeyConst.data()),
-                         clientKeyConst.size());
+        SHA1Block::computeHmac(saltedPassword.data(),
+                               saltedPassword.size(),
+                               reinterpret_cast<const unsigned char*>(clientKeyConst.data()),
+                               clientKeyConst.size());
 
     // StoredKey := H(clientKey)
     credentials.storedKey =
-        crypto::sha1(credentials.clientKey->data(), credentials.clientKey->size());
+        SHA1Block::computeHash(credentials.clientKey->data(), credentials.clientKey->size());
 
     // ServerKey       := HMAC(SaltedPassword, "Server Key")
     credentials.serverKey =
-        crypto::hmacSha1(saltedPassword.data(),
-                         saltedPassword.size(),
-                         reinterpret_cast<const unsigned char*>(serverKeyConst.data()),
-                         serverKeyConst.size());
+        SHA1Block::computeHmac(saltedPassword.data(),
+                               saltedPassword.size(),
+                               reinterpret_cast<const unsigned char*>(serverKeyConst.data()),
+                               serverKeyConst.size());
 
     return credentials;
 }
@@ -171,8 +164,8 @@ BSONObj generateCredentials(const std::string& hashedPassword, int iterationCoun
                                                       saltLenQWords * sizeof(uint64_t)),
                         iterationCount));
 
-    std::string encodedStoredKey = hashToBase64(secrets.storedKey);
-    std::string encodedServerKey = hashToBase64(secrets.serverKey);
+    std::string encodedStoredKey = secrets.storedKey->toString();
+    std::string encodedServerKey = secrets.serverKey->toString();
 
     return BSON(iterationCountFieldName << iterationCount << saltFieldName << encodedUserSalt
                                         << storedKeyFieldName << encodedStoredKey
@@ -182,32 +175,27 @@ BSONObj generateCredentials(const std::string& hashedPassword, int iterationCoun
 std::string generateClientProof(const SCRAMSecrets& clientCredentials,
                                 const std::string& authMessage) {
     // ClientSignature := HMAC(StoredKey, AuthMessage)
-    SHA1Hash clientSignature =
-        crypto::hmacSha1(clientCredentials.storedKey->data(),
-                         clientCredentials.storedKey->size(),
-                         reinterpret_cast<const unsigned char*>(authMessage.c_str()),
-                         authMessage.size());
-
-    // ClientProof   := ClientKey XOR ClientSignature
-    SHA1Hash clientProof;
-    for (size_t i = 0; i < clientCredentials.clientKey->size(); i++) {
-        clientProof[i] = (*clientCredentials.clientKey)[i] ^ clientSignature[i];
-    }
-
-    return hashToBase64(clientProof);
+    SHA1Block clientSignature =
+        SHA1Block::computeHmac(clientCredentials.storedKey->data(),
+                               clientCredentials.storedKey->size(),
+                               reinterpret_cast<const unsigned char*>(authMessage.c_str()),
+                               authMessage.size());
+
+    clientSignature.xorInline(*clientCredentials.clientKey);
+    return clientSignature.toString();
 }
 
 bool verifyServerSignature(const SCRAMSecrets& clientCredentials,
                            const std::string& authMessage,
                            const std::string& receivedServerSignature) {
     // ServerSignature := HMAC(ServerKey, AuthMessage)
-    SHA1Hash serverSignature =
-        crypto::hmacSha1(clientCredentials.serverKey->data(),
-                         clientCredentials.serverKey->size(),
-                         reinterpret_cast<const unsigned char*>(authMessage.c_str()),
-                         authMessage.size());
+    SHA1Block serverSignature =
+        SHA1Block::computeHmac(clientCredentials.serverKey->data(),
+                               clientCredentials.serverKey->size(),
+                               reinterpret_cast<const unsigned char*>(authMessage.c_str()),
+                               authMessage.size());
 
-    std::string encodedServerSignature = hashToBase64(serverSignature);
+    std::string encodedServerSignature = serverSignature.toString();
 
     if (encodedServerSignature.size() != receivedServerSignature.size()) {
         return false;
@@ -221,20 +209,20 @@ bool verifyServerSignature(const SCRAMSecrets& clientCredentials,
 
 bool verifyClientProof(StringData clientProof, StringData storedKey, StringData authMessage) {
     // ClientSignature := HMAC(StoredKey, AuthMessage)
-    SHA1Hash clientSignature =
-        crypto::hmacSha1(reinterpret_cast<const unsigned char*>(storedKey.rawData()),
-                         storedKey.size(),
-                         reinterpret_cast<const unsigned char*>(authMessage.rawData()),
-                         authMessage.size());
-
-    // ClientKey := ClientSignature XOR ClientProof
-    SHA1Hash clientKey;
-    for (size_t i = 0; i < clientKey.size(); i++) {
-        clientKey[i] = clientSignature[i] ^ clientProof.rawData()[i];
-    }
-
-    // StoredKey := H(ClientKey)
-    SHA1Hash computedStoredKey = crypto::sha1(clientKey.data(), clientKey.size());
+    SHA1Block clientSignature =
+        SHA1Block::computeHmac(reinterpret_cast<const unsigned char*>(storedKey.rawData()),
+                               storedKey.size(),
+                               reinterpret_cast<const unsigned char*>(authMessage.rawData()),
+                               authMessage.size());
+
+    auto clientProofSHA1Status = SHA1Block::fromBuffer(
+        reinterpret_cast<const uint8_t*>(clientProof.rawData()), clientProof.size());
+    uassertStatusOK(clientProofSHA1Status);
+    clientSignature.xorInline(clientProofSHA1Status.getValue());
+
+    // StoredKey := H(clientSignature)
+    SHA1Block computedStoredKey =
+        SHA1Block::computeHash(clientSignature.data(), clientSignature.size());
 
     return consttimeMemEqual(reinterpret_cast<const unsigned char*>(storedKey.rawData()),
                              computedStoredKey.data(),
diff --git a/src/mongo/crypto/mechanism_scram.h b/src/mongo/crypto/mechanism_scram.h
index 1d3b86f2fdd..fb070e8162c 100644
--- a/src/mongo/crypto/mechanism_scram.h
+++ b/src/mongo/crypto/mechanism_scram.h
@@ -32,13 +32,11 @@
 
 #include "mongo/base/secure_allocator.h"
 #include "mongo/base/status.h"
-#include "mongo/crypto/crypto.h"
+#include "mongo/crypto/sha1_block.h"
 #include "mongo/db/jsobj.h"
 
 namespace mongo {
 namespace scram {
-// Convert a SHA1Hash into a base64 encoded string.
-std::string hashToBase64(const SecureHandle<SHA1Hash>& hash);
 
 const std::string serverKeyConst = "Server Key";
 const std::string clientKeyConst = "Client Key";
@@ -74,16 +72,16 @@ inline bool operator==(const SCRAMPresecrets& lhs, const SCRAMPresecrets& rhs) {
 /*
  * Computes the SaltedPassword from password, salt and iterationCount.
  */
-SHA1Hash generateSaltedPassword(const SCRAMPresecrets& presecrets);
+SHA1Block generateSaltedPassword(const SCRAMPresecrets& presecrets);
 
 /*
  * Stores all of the keys, generated from a password, needed for a client or server to perform a
  * SCRAM handshake. This structure will secureZeroMemory itself on destruction.
  */
 struct SCRAMSecrets {
-    SecureHandle<SHA1Hash> clientKey;
-    SecureHandle<SHA1Hash> storedKey;
-    SecureHandle<SHA1Hash> serverKey;
+    SecureHandle<SHA1Block> clientKey;
+    SecureHandle<SHA1Block> storedKey;
+    SecureHandle<SHA1Block> serverKey;
 };
 
 /*
@@ -95,7 +93,7 @@ SCRAMSecrets generateSecrets(const SCRAMPresecrets& presecrets);
 /*
  * Computes the ClientKey and StoredKey from SaltedPassword (client side).
  */
-SCRAMSecrets generateSecrets(const SHA1Hash& saltedPassword);
+SCRAMSecrets generateSecrets(const SHA1Block& saltedPassword);
 
 /*
  * Generates the user salt and the SCRAM secrets storedKey and serverKey as
diff --git a/src/mongo/crypto/sha1_block.cpp b/src/mongo/crypto/sha1_block.cpp
new file mode 100644
index 00000000000..43565419a7d
--- /dev/null
+++ b/src/mongo/crypto/sha1_block.cpp
@@ -0,0 +1,88 @@
+/**
+ *    Copyright (C) 2017 MongoDB, Inc.
+ *
+ *    This program is free software: you can redistribute it and/or  modify
+ *    it under the terms of the GNU Affero General Public License, version 3,
+ *    as published by the Free Software Foundation.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    GNU Affero General Public License for more details.
+ *
+ *    You should have received a copy of the GNU Affero General Public License
+ *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ *    As a special exception, the copyright holders give permission to link the
+ *    code of portions of this program with the OpenSSL library under certain
+ *    conditions as described in each individual source file and distribute
+ *    linked combinations including the program with the OpenSSL library. You
+ *    must comply with the GNU Affero General Public License in all respects for
+ *    all of the code used other than as permitted herein. If you modify file(s)
+ *    with this exception, you may extend this exception to your version of the
+ *    file(s), but you are not obligated to do so. If you do not wish to do so,
+ *    delete this exception statement from your version. If you delete this
+ *    exception statement from all source files in the program, then also delete
+ *    it in the license file.
+ */
+
+#include "mongo/platform/basic.h"
+
+#include "mongo/crypto/sha1_block.h"
+
+#include "mongo/bson/bsonmisc.h"
+#include "mongo/bson/bsonobjbuilder.h"
+#include "mongo/util/base64.h"
+#include "mongo/util/mongoutils/str.h"
+
+namespace mongo {
+
+const size_t SHA1Block::kHashLength = 20;
+
+SHA1Block::SHA1Block(HashType hash) : _hash(std::move(hash)) {}
+
+StatusWith<SHA1Block> SHA1Block::fromBuffer(const uint8_t* input, size_t inputLen) {
+    if (inputLen != kHashLength) {
+        return {ErrorCodes::InvalidLength,
+                str::stream() << "Unsupported SHA1Hash hash length: " << inputLen};
+    }
+
+    HashType newHash;
+    memcpy(newHash.data(), input, inputLen);
+    return SHA1Block(newHash);
+}
+
+StatusWith<SHA1Block> SHA1Block::fromBinData(const BSONBinData& binData) {
+    if (binData.type != BinDataGeneral) {
+        return {ErrorCodes::UnsupportedFormat, "SHA1Block only accepts BinDataGeneral type"};
+    }
+
+    if (binData.length != kHashLength) {
+        return {ErrorCodes::UnsupportedFormat,
+                str::stream() << "Unsupported SHA1Block hash length: " << binData.length};
+    }
+
+    HashType newHash;
+    memcpy(newHash.data(), binData.data, binData.length);
+    return SHA1Block(newHash);
+}
+
+std::string SHA1Block::toString() const {
+    return base64::encode(reinterpret_cast<const char*>(_hash.data()), _hash.size());
+}
+
+void SHA1Block::appendAsBinData(BSONObjBuilder& builder, StringData fieldName) {
+    builder.appendBinData(fieldName, _hash.size(), BinDataGeneral, _hash.data());
+}
+
+void SHA1Block::xorInline(const SHA1Block& other) {
+    for (size_t x = 0; x < _hash.size(); x++) {
+        _hash[x] ^= other._hash[x];
+    }
+}
+
+bool SHA1Block::operator==(const SHA1Block& rhs) const {
+    return rhs._hash == this->_hash;
+}
+
+}  // namespace mongo
diff --git a/src/mongo/crypto/sha1_block.h b/src/mongo/crypto/sha1_block.h
new file mode 100644
index 00000000000..280177de309
--- /dev/null
+++ b/src/mongo/crypto/sha1_block.h
@@ -0,0 +1,99 @@
+/**
+*    Copyright (C) 2017 MongoDB Inc.
+*
+*    This program is free software: you can redistribute it and/or  modify
+*    it under the terms of the GNU Affero General Public License, version 3,
+*    as published by the Free Software Foundation.
+*
+*    This program is distributed in the hope that it will be useful,
+*    but WITHOUT ANY WARRANTY; without even the implied warranty of
+*    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+*    GNU Affero General Public License for more details.
+*
+*    You should have received a copy of the GNU Affero General Public License
+*    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*
+*    As a special exception, the copyright holders give permission to link the
+*    code of portions of this program with the OpenSSL library under certain
+*    conditions as described in each individual source file and distribute
+*    linked combinations including the program with the OpenSSL library. You
+*    must comply with the GNU Affero General Public License in all respects for
+*    all of the code used other than as permitted herein. If you modify file(s)
+*    with this exception, you may extend this exception to your version of the
+*    file(s), but you are not obligated to do so. If you do not wish to do so,
+*    delete this exception statement from your version. If you delete this
+*    exception statement from all source files in the program, then also delete
+*    it in the license file.
+*/
+
+#pragma once
+
+#include <array>
+#include <cstddef>
+#include <string>
+
+#include "mongo/base/status_with.h"
+
+namespace mongo {
+
+struct BSONBinData;
+class BSONObjBuilder;
+
+/**
+ * Data structure with fixed sized byte array that can be used as HMAC key or result of a SHA1
+ * computation.
+ */
+class SHA1Block {
+public:
+    static const size_t kHashLength;  // 20
+    using HashType = std::array<uint8_t, 20>;
+
+    SHA1Block() = default;
+    SHA1Block(HashType rawHash);
+    static StatusWith<SHA1Block> fromBuffer(const uint8_t* input, size_t inputLen);
+
+    /**
+     * Computes a SHA-1 hash of 'input'.
+     */
+    static SHA1Block computeHash(const uint8_t* input, size_t inputLen);
+
+    /**
+     * Computes a HMAC SHA-1 keyed hash of 'input' using the key 'key'
+     */
+    static SHA1Block computeHmac(const uint8_t* key,
+                                 size_t keyLen,
+                                 const uint8_t* input,
+                                 size_t inputLen);
+
+    const uint8_t* data() const {
+        return _hash.data();
+    }
+
+    size_t size() const {
+        return _hash.size();
+    }
+
+    /**
+     * Make a new SHA1Block from a BSON BinData value.
+     */
+    static StatusWith<SHA1Block> fromBinData(const BSONBinData& binData);
+
+    /**
+     * Append this to a builder using the given name as a BSON BinData type value.
+     */
+    void appendAsBinData(BSONObjBuilder& builder, StringData fieldName);
+
+    /**
+     * Do a bitwise xor against another SHA1Block and replace the current contents of this block
+     * with the result.
+     */
+    void xorInline(const SHA1Block& other);
+
+    std::string toString() const;
+    bool operator==(const SHA1Block& rhs) const;
+
+private:
+    HashType _hash;
+};
+
+}  // namespace mongo
diff --git a/src/mongo/crypto/crypto_openssl.cpp b/src/mongo/crypto/sha1_block_openssl.cpp
index d7e310e0d46..50d18b9bace 100644
--- a/src/mongo/crypto/crypto_openssl.cpp
+++ b/src/mongo/crypto/sha1_block_openssl.cpp
@@ -28,8 +28,10 @@
 
 #include "mongo/platform/basic.h"
 
+#include "mongo/crypto/sha1_block.h"
+
 #include "mongo/config.h"
-#include "mongo/crypto/crypto.h"
+#include "mongo/stdx/memory.h"
 #include "mongo/util/assert_util.h"
 #include "mongo/util/scopeguard.h"
 
@@ -62,12 +64,11 @@ void EVP_MD_CTX_free(EVP_MD_CTX* ctx) {
 #endif
 
 namespace mongo {
-namespace crypto {
 /*
  * Computes a SHA-1 hash of 'input'.
  */
-SHA1Hash sha1(const unsigned char* input, const size_t inputLen) {
-    SHA1Hash output;
+SHA1Block SHA1Block::computeHash(const uint8_t* input, size_t inputLen) {
+    HashType output;
 
     EVP_MD_CTX digestCtx;
     EVP_MD_CTX_init(&digestCtx);
@@ -77,20 +78,19 @@ SHA1Hash sha1(const unsigned char* input, const size_t inputLen) {
             EVP_DigestInit_ex(&digestCtx, EVP_sha1(), NULL) == 1 &&
                 EVP_DigestUpdate(&digestCtx, input, inputLen) == 1 &&
                 EVP_DigestFinal_ex(&digestCtx, output.data(), NULL) == 1);
-    return output;
+    return SHA1Block(output);
 }
 
 /*
  * Computes a HMAC SHA-1 keyed hash of 'input' using the key 'key'
  */
-SHA1Hash hmacSha1(const unsigned char* key,
-                  const size_t keyLen,
-                  const unsigned char* input,
-                  const size_t inputLen) {
-    SHA1Hash output;
+SHA1Block SHA1Block::computeHmac(const uint8_t* key,
+                                 size_t keyLen,
+                                 const uint8_t* input,
+                                 size_t inputLen) {
+    HashType output;
     fassert(40380, HMAC(EVP_sha1(), key, keyLen, input, inputLen, output.data(), NULL) != NULL);
-    return output;
+    return SHA1Block(output);
 }
 
-}  // namespace crypto
 }  // namespace mongo
diff --git a/src/mongo/crypto/crypto_test.cpp b/src/mongo/crypto/sha1_block_test.cpp
index 8c8d3928c75..111132ff388 100644
--- a/src/mongo/crypto/crypto_test.cpp
+++ b/src/mongo/crypto/sha1_block_test.cpp
@@ -26,7 +26,11 @@
  *    then also delete it in the license file.
  */
 
-#include "mongo/crypto/crypto.h"
+#include "mongo/platform/basic.h"
+
+#include "mongo/bson/bsonmisc.h"
+#include "mongo/bson/bsonobjbuilder.h"
+#include "mongo/crypto/sha1_block.h"
 #include "mongo/unittest/unittest.h"
 
 namespace mongo {
@@ -35,58 +39,21 @@ namespace {
 // SHA-1 test vectors from http://csrc.nist.gov/groups/ST/toolkit/documents/Examples/SHA_All.pdf
 const struct {
     const char* msg;
-    SHA1Hash hash;
-} sha1Tests[] = {{"abc",
-                  {0xa9,
-                   0x99,
-                   0x3e,
-                   0x36,
-                   0x47,
-                   0x06,
-                   0x81,
-                   0x6a,
-                   0xba,
-                   0x3e,
-                   0x25,
-                   0x71,
-                   0x78,
-                   0x50,
-                   0xc2,
-                   0x6c,
-                   0x9c,
-                   0xd0,
-                   0xd8,
-                   0x9d}},
+    SHA1Block hash;
+} sha1Tests[] = {
+    {"abc", SHA1Block::HashType{0xa9, 0x99, 0x3e, 0x36, 0x47, 0x06, 0x81, 0x6a, 0xba, 0x3e,
+                                0x25, 0x71, 0x78, 0x50, 0xc2, 0x6c, 0x9c, 0xd0, 0xd8, 0x9d}},
 
-                 {"abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq",
-                  {0x84,
-                   0x98,
-                   0x3E,
-                   0x44,
-                   0x1C,
-                   0x3B,
-                   0xD2,
-                   0x6E,
-                   0xBA,
-                   0xAE,
-                   0x4A,
-                   0xA1,
-                   0xF9,
-                   0x51,
-                   0x29,
-                   0xE5,
-                   0xE5,
-                   0x46,
-                   0x70,
-                   0xF1}}};
+    {"abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq",
+     SHA1Block::HashType{0x84, 0x98, 0x3E, 0x44, 0x1C, 0x3B, 0xD2, 0x6E, 0xBA, 0xAE,
+                         0x4A, 0xA1, 0xF9, 0x51, 0x29, 0xE5, 0xE5, 0x46, 0x70, 0xF1}}};
 
 TEST(CryptoVectors, SHA1) {
     size_t numTests = sizeof(sha1Tests) / sizeof(sha1Tests[0]);
     for (size_t i = 0; i < numTests; i++) {
-        SHA1Hash result = crypto::sha1(reinterpret_cast<const unsigned char*>(sha1Tests[i].msg),
-                                       strlen(sha1Tests[i].msg));
-        ASSERT(0 == memcmp(sha1Tests[i].hash.data(), result.data(), result.size()))
-            << "Failed SHA1 iteration " << i;
+        SHA1Block result = SHA1Block::computeHash(
+            reinterpret_cast<const unsigned char*>(sha1Tests[i].msg), strlen(sha1Tests[i].msg));
+        ASSERT(sha1Tests[i].hash == result) << "Failed SHA1 iteration " << i;
     }
 }
 
@@ -98,7 +65,7 @@ const struct {
     int keyLen;
     unsigned char data[maxDataSize];
     int dataLen;
-    SHA1Hash hash;
+    SHA1Block hash;
 } hmacSha1Tests[] = {
     // RFC test case 1
     {{0x0b,
@@ -124,26 +91,8 @@ const struct {
      20,
      {0x48, 0x69, 0x20, 0x54, 0x68, 0x65, 0x72, 0x65},
      8,
-     {0xb6,
-      0x17,
-      0x31,
-      0x86,
-      0x55,
-      0x05,
-      0x72,
-      0x64,
-      0xe2,
-      0x8b,
-      0xc0,
-      0xb6,
-      0xfb,
-      0x37,
-      0x8c,
-      0x8e,
-      0xf1,
-      0x46,
-      0xbe,
-      0x00}},
+     SHA1Block::HashType{0xb6, 0x17, 0x31, 0x86, 0x55, 0x05, 0x72, 0x64, 0xe2, 0x8b,
+                         0xc0, 0xb6, 0xfb, 0x37, 0x8c, 0x8e, 0xf1, 0x46, 0xbe, 0x00}},
 
     // RFC test case 3
     {{0xaa,
@@ -218,26 +167,8 @@ const struct {
       0xdd,
       0xdd},
      50,
-     {0x12,
-      0x5d,
-      0x73,
-      0x42,
-      0xb9,
-      0xac,
-      0x11,
-      0xcd,
-      0x91,
-      0xa3,
-      0x9a,
-      0xf4,
-      0x8a,
-      0xa1,
-      0x7b,
-      0x4f,
-      0x63,
-      0xf1,
-      0x75,
-      0xd3}},
+     SHA1Block::HashType{0x12, 0x5d, 0x73, 0x42, 0xb9, 0xac, 0x11, 0xcd, 0x91, 0xa3,
+                         0x9a, 0xf4, 0x8a, 0xa1, 0x7b, 0x4f, 0x63, 0xf1, 0x75, 0xd3}},
 
     // RFC test case 4
     {{0x01,
@@ -317,26 +248,8 @@ const struct {
       0xcd,
       0xcd},
      50,
-     {0x4c,
-      0x90,
-      0x07,
-      0xf4,
-      0x02,
-      0x62,
-      0x50,
-      0xc6,
-      0xbc,
-      0x84,
-      0x14,
-      0xf9,
-      0xbf,
-      0x50,
-      0xc8,
-      0x6c,
-      0x2d,
-      0x72,
-      0x35,
-      0xda}},
+     SHA1Block::HashType{0x4c, 0x90, 0x07, 0xf4, 0x02, 0x62, 0x50, 0xc6, 0xbc, 0x84,
+                         0x14, 0xf9, 0xbf, 0x50, 0xc8, 0x6c, 0x2d, 0x72, 0x35, 0xda}},
 
     // RFC test case 6
     {{0xaa,
@@ -475,37 +388,70 @@ const struct {
       0x73,
       0x74},
      54,
-     {0xaa,
-      0x4a,
-      0xe5,
-      0xe1,
-      0x52,
-      0x72,
-      0xd0,
-      0x0e,
-      0x95,
-      0x70,
-      0x56,
-      0x37,
-      0xce,
-      0x8a,
-      0x3b,
-      0x55,
-      0xed,
-      0x40,
-      0x21,
-      0x12}}};
+     SHA1Block::HashType{0xaa, 0x4a, 0xe5, 0xe1, 0x52, 0x72, 0xd0, 0x0e, 0x95, 0x70,
+                         0x56, 0x37, 0xce, 0x8a, 0x3b, 0x55, 0xed, 0x40, 0x21, 0x12}}};
 
 TEST(CryptoVectors, HMACSHA1) {
     size_t numTests = sizeof(hmacSha1Tests) / sizeof(hmacSha1Tests[0]);
     for (size_t i = 0; i < numTests; i++) {
-        SHA1Hash result = crypto::hmacSha1(hmacSha1Tests[i].key,
-                                           hmacSha1Tests[i].keyLen,
-                                           hmacSha1Tests[i].data,
-                                           hmacSha1Tests[i].dataLen);
-        ASSERT(0 == memcmp(hmacSha1Tests[i].hash.data(), result.data(), result.size()))
-            << "Failed HMAC-SHA1 iteration " << i;
+        SHA1Block result = SHA1Block::computeHmac(hmacSha1Tests[i].key,
+                                                  hmacSha1Tests[i].keyLen,
+                                                  hmacSha1Tests[i].data,
+                                                  hmacSha1Tests[i].dataLen);
+        ASSERT(hmacSha1Tests[i].hash == result) << "Failed HMAC-SHA1 iteration " << i;
     }
 }
+
+TEST(SHA1Block, BinDataRoundTrip) {
+    SHA1Block::HashType rawHash;
+    rawHash.fill(0);
+    for (size_t i = 0; i < rawHash.size(); i++) {
+        rawHash[i] = i;
+    }
+
+    SHA1Block testHash(rawHash);
+
+    BSONObjBuilder builder;
+    testHash.appendAsBinData(builder, "hash");
+    auto newObj = builder.done();
+
+    auto hashElem = newObj["hash"];
+    ASSERT_EQ(BinData, hashElem.type());
+    ASSERT_EQ(BinDataGeneral, hashElem.binDataType());
+
+    int binLen = 0;
+    auto rawBinData = hashElem.binData(binLen);
+    ASSERT_EQ(SHA1Block::kHashLength, static_cast<size_t>(binLen));
+
+    auto newHashStatus =
+        SHA1Block::fromBinData(BSONBinData(rawBinData, binLen, hashElem.binDataType()));
+    ASSERT_OK(newHashStatus.getStatus());
+    ASSERT_TRUE(testHash == newHashStatus.getValue());
+}
+
+TEST(SHA1Block, CanOnlyConstructFromBinGeneral) {
+    std::string dummy(SHA1Block::kHashLength, 'x');
+
+    auto newHashStatus = SHA1Block::fromBinData(BSONBinData(dummy.c_str(), dummy.size(), newUUID));
+    ASSERT_EQ(ErrorCodes::UnsupportedFormat, newHashStatus.getStatus());
+}
+
+TEST(SHA1Block, FromBinDataShouldRegectWrongSize) {
+    std::string dummy(SHA1Block::kHashLength - 1, 'x');
+
+    auto newHashStatus =
+        SHA1Block::fromBinData(BSONBinData(dummy.c_str(), dummy.size(), BinDataGeneral));
+    ASSERT_EQ(ErrorCodes::UnsupportedFormat, newHashStatus.getStatus());
+}
+
+TEST(SHA1Block, FromBufferShouldRejectWrongLength) {
+    std::string dummy(SHA1Block::kHashLength - 1, 'x');
+
+    auto newHashStatus =
+        SHA1Block::fromBuffer(reinterpret_cast<const uint8_t*>(dummy.c_str()), dummy.size());
+    ASSERT_EQ(ErrorCodes::InvalidLength, newHashStatus.getStatus());
+}
+
+
 }  // namespace
 }  // namespace mongo
diff --git a/src/mongo/crypto/crypto_tom.cpp b/src/mongo/crypto/sha1_block_tom.cpp
index 904eb5925e3..d1078e60458 100644
--- a/src/mongo/crypto/crypto_tom.cpp
+++ b/src/mongo/crypto/sha1_block_tom.cpp
@@ -28,8 +28,9 @@
 
 #include "mongo/platform/basic.h"
 
+#include "mongo/crypto/sha1_block.h"
+
 #include "mongo/config.h"
-#include "mongo/crypto/crypto.h"
 #include "mongo/util/assert_util.h"
 
 #ifdef MONGO_CONFIG_SSL
@@ -39,30 +40,30 @@
 #include "mongo/crypto/tom/tomcrypt.h"
 
 namespace mongo {
-namespace crypto {
+
 /*
  * Computes a SHA-1 hash of 'input'.
  */
-SHA1Hash sha1(const unsigned char* input, const size_t inputLen) {
-    SHA1Hash output;
+SHA1Block SHA1Block::computeHash(const uint8_t* input, size_t inputLen) {
+    HashType output;
 
     hash_state hashState;
     fassert(40381,
             sha1_init(&hashState) == CRYPT_OK &&
                 sha1_process(&hashState, input, inputLen) == CRYPT_OK &&
                 sha1_done(&hashState, output.data()) == CRYPT_OK);
-    return output;
+    return SHA1Block(output);
 }
 
 /*
  * Computes a HMAC SHA-1 keyed hash of 'input' using the key 'key'
  */
-SHA1Hash hmacSha1(const unsigned char* key,
-                  const size_t keyLen,
-                  const unsigned char* input,
-                  const size_t inputLen) {
+SHA1Block SHA1Block::computeHmac(const uint8_t* key,
+                                 size_t keyLen,
+                                 const uint8_t* input,
+                                 size_t inputLen) {
     invariant(key && input);
-    SHA1Hash output;
+    HashType output;
 
     static int hashId = -1;
     if (hashId == -1) {
@@ -74,8 +75,7 @@ SHA1Hash hmacSha1(const unsigned char* key,
     fassert(40382,
             hmac_memory(hashId, key, keyLen, input, inputLen, output.data(), &sha1HashLen) ==
                 CRYPT_OK);
-    return output;
+    return SHA1Block(output);
 }
 
-}  // namespace crypto
 }  // namespace mongo
diff --git a/src/mongo/db/auth/sasl_scramsha1_server_conversation.cpp b/src/mongo/db/auth/sasl_scramsha1_server_conversation.cpp
index 11848fb5ba9..5809306456d 100644
--- a/src/mongo/db/auth/sasl_scramsha1_server_conversation.cpp
+++ b/src/mongo/db/auth/sasl_scramsha1_server_conversation.cpp
@@ -35,8 +35,8 @@
 #include <boost/algorithm/string/join.hpp>
 #include <boost/algorithm/string/replace.hpp>
 
-#include "mongo/crypto/crypto.h"
 #include "mongo/crypto/mechanism_scram.h"
+#include "mongo/crypto/sha1_block.h"
 #include "mongo/db/auth/sasl_options.h"
 #include "mongo/platform/random.h"
 #include "mongo/util/base64.h"
@@ -284,14 +284,14 @@ StatusWith<bool> SaslSCRAMSHA1ServerConversation::_secondStep(const std::vector<
 
     // ServerSignature := HMAC(ServerKey, AuthMessage)
     std::string decodedServerKey = base64::decode(_creds.scram.serverKey);
-    SHA1Hash serverSignature =
-        crypto::hmacSha1(reinterpret_cast<const unsigned char*>(decodedServerKey.c_str()),
-                         decodedServerKey.size(),
-                         reinterpret_cast<const unsigned char*>(_authMessage.c_str()),
-                         _authMessage.size());
+    SHA1Block serverSignature =
+        SHA1Block::computeHmac(reinterpret_cast<const unsigned char*>(decodedServerKey.c_str()),
+                               decodedServerKey.size(),
+                               reinterpret_cast<const unsigned char*>(_authMessage.c_str()),
+                               _authMessage.size());
 
     StringBuilder sb;
-    sb << "v=" << scram::hashToBase64(serverSignature);
+    sb << "v=" << serverSignature.toString();
     *outputData = sb.str();
 
     return StatusWith<bool>(false);