Core/Authserver: Authserver cleanup (PR#25093)

- Fix a handful of 1/256 bugs with most significant byte zero in BigNumber
- Get rid of (most of) the C-style arrays in authserver
- CryptoRandom as a unified source for cryptographic randomness
- Bring our other crypto APIs into 2020
- BigNumber usability improvements
- Authserver is now actually readable as a result of all of the above

(cherry picked from commit 210176fd915cf4ba16f428d3c1a249a71f4aa7a7)

1 files changed, 16 insertions, 6 deletions

diff --git a/src/common/Cryptography/AES.cpp b/src/common/Cryptography/AES.cpp
index 08762e224e9..7d4ccc7c46f 100644
--- a/src/common/Cryptography/AES.cpp
+++ b/src/common/Cryptography/AES.cpp
@@ -16,11 +16,14 @@
  */
 
 #include "AES.h"
+#include "Errors.h"
+#include <limits>
 
 Trinity::Crypto::AES::AES(bool encrypting) : _ctx(EVP_CIPHER_CTX_new()), _encrypting(encrypting)
 {
     EVP_CIPHER_CTX_init(_ctx);
-    EVP_CipherInit_ex(_ctx, EVP_aes_128_gcm(), nullptr, nullptr, nullptr, _encrypting ? 1 : 0);
+    int status = EVP_CipherInit_ex(_ctx, EVP_aes_128_gcm(), nullptr, nullptr, nullptr, _encrypting ? 1 : 0);
+    ASSERT(status);
 }
 
 Trinity::Crypto::AES::~AES()
@@ -28,26 +31,33 @@ Trinity::Crypto::AES::~AES()
     EVP_CIPHER_CTX_free(_ctx);
 }
 
-void Trinity::Crypto::AES::Init(uint8 const* key)
+void Trinity::Crypto::AES::Init(Key const& key)
 {
-    EVP_CipherInit_ex(_ctx, nullptr, nullptr, key, nullptr, -1);
+    int status = EVP_CipherInit_ex(_ctx, nullptr, nullptr, key.data(), nullptr, -1);
+    ASSERT(status);
 }
 
-bool Trinity::Crypto::AES::Process(uint8 const* iv, uint8* data, std::size_t length, uint8(&tag)[12])
+bool Trinity::Crypto::AES::Process(IV const& iv, uint8* data, size_t length, Tag& tag)
 {
-    if (!EVP_CipherInit_ex(_ctx, nullptr, nullptr, nullptr, iv, -1))
+    ASSERT(length <= std::numeric_limits<int>::max());
+    int len = static_cast<int>(length);
+    if (!EVP_CipherInit_ex(_ctx, nullptr, nullptr, nullptr, iv.data(), -1))
         return false;
 
     int outLen;
-    if (!EVP_CipherUpdate(_ctx, data, &outLen, data, length))
+    if (!EVP_CipherUpdate(_ctx, data, &outLen, data, len))
         return false;
 
+    len -= outLen;
+
     if (!_encrypting && !EVP_CIPHER_CTX_ctrl(_ctx, EVP_CTRL_GCM_SET_TAG, sizeof(tag), tag))
         return false;
 
     if (!EVP_CipherFinal_ex(_ctx, data + outLen, &outLen))
         return false;
 
+    ASSERT(len == outLen);
+
     if (_encrypting && !EVP_CIPHER_CTX_ctrl(_ctx, EVP_CTRL_GCM_GET_TAG, sizeof(tag), tag))
         return false;