Revert "SERVER-43641 upgrade random.h"

This reverts commit 96da177c6ae7b7ed0f29983ad033d8a59524b0b2.

2 files changed, 23 insertions, 4 deletions

diff --git a/src/mongo/crypto/mechanism_scram.h b/src/mongo/crypto/mechanism_scram.h
index 5e0265679ea..fcb16331830 100644
--- a/src/mongo/crypto/mechanism_scram.h
+++ b/src/mongo/crypto/mechanism_scram.h
@@ -102,9 +102,15 @@ public:
     }
 
     static std::vector<std::uint8_t> generateSecureRandomSalt() {
-        std::vector<std::uint8_t> salt(saltLength());
-        SecureRandom().fill(salt.data(), salt.size());
-        return salt;
+        // Express salt length as a number of quad words, rounded up.
+        constexpr auto qwords = (saltLength() + sizeof(std::int64_t) - 1) / sizeof(std::int64_t);
+        std::array<std::int64_t, qwords> userSalt;
+
+        std::unique_ptr<SecureRandom> sr(SecureRandom::create());
+        std::generate(userSalt.begin(), userSalt.end(), [&sr] { return sr->nextInt64(); });
+        return std::vector<std::uint8_t>(reinterpret_cast<std::uint8_t*>(userSalt.data()),
+                                         reinterpret_cast<std::uint8_t*>(userSalt.data()) +
+                                             saltLength());
     }
 
 private:
diff --git a/src/mongo/crypto/symmetric_crypto.cpp b/src/mongo/crypto/symmetric_crypto.cpp
index 0a6bbc2e916..32d888cfbbb 100644
--- a/src/mongo/crypto/symmetric_crypto.cpp
+++ b/src/mongo/crypto/symmetric_crypto.cpp
@@ -48,7 +48,12 @@
 namespace mongo {
 namespace crypto {
 
+namespace {
+std::unique_ptr<SecureRandom> random;
+}  // namespace
+
 MONGO_INITIALIZER(CreateKeyEntropySource)(InitializerContext* context) {
+    random = std::unique_ptr<SecureRandom>(SecureRandom::create());
     return Status::OK();
 }
 
@@ -85,8 +90,16 @@ std::string getStringFromCipherMode(aesMode mode) {
 
 SymmetricKey aesGenerate(size_t keySize, SymmetricKeyId keyId) {
     invariant(keySize == sym256KeySize);
+
     SecureVector<uint8_t> key(keySize);
-    SecureRandom().fill(key->data(), key->size());
+
+    size_t offset = 0;
+    while (offset < keySize) {
+        std::uint64_t randomValue = random->nextInt64();
+        memcpy(key->data() + offset, &randomValue, sizeof(randomValue));
+        offset += sizeof(randomValue);
+    }
+
     return SymmetricKey(std::move(key), aesAlgorithm, std::move(keyId));
 }