From 44991943015a862e2b1df0a898432bcd73cb7258 Mon Sep 17 00:00:00 2001
From: cloudwebrtc <duanweiwei1982@gmail.com>
Date: Tue, 17 Sep 2024 22:03:25 +0800
Subject: [PATCH] chore: remove aes cbc for framecryptor.

---
 api/crypto/frame_crypto_transformer.cc        | 47 ++-----------------
 .../api/org/webrtc/FrameCryptorAlgorithm.java |  1 -
 sdk/android/src/jni/pc/frame_cryptor.cc       |  2 -
 sdk/objc/api/peerconnection/RTCFrameCryptor.h |  1 -
 .../api/peerconnection/RTCFrameCryptor.mm     |  2 -
 5 files changed, 3 insertions(+), 50 deletions(-)

diff --git a/api/crypto/frame_crypto_transformer.cc b/api/crypto/frame_crypto_transformer.cc
index 8c26080cb7..5f6ea55a60 100644
--- a/api/crypto/frame_crypto_transformer.cc
+++ b/api/crypto/frame_crypto_transformer.cc
@@ -250,46 +250,6 @@ int AesGcmEncryptDecrypt(EncryptOrDecrypt mode,
   return Success;
 }
 
-int AesCbcEncryptDecrypt(EncryptOrDecrypt mode,
-                         const std::vector<uint8_t>& raw_key,
-                         rtc::ArrayView<uint8_t> iv,
-                         const rtc::ArrayView<uint8_t> input,
-                         std::vector<uint8_t>* output) {
-  const EVP_CIPHER* cipher = GetAesCbcAlgorithmFromKeySize(raw_key.size());
-  if (!cipher) {
-    RTC_LOG(LS_ERROR) << "Invalid AES-CBC key size.";
-    return ErrorUnexpected;
-  }
-  RTC_DCHECK_EQ(EVP_CIPHER_iv_length(cipher), iv.size());
-  RTC_DCHECK_EQ(EVP_CIPHER_key_length(cipher), raw_key.size());
-
-  bssl::ScopedEVP_CIPHER_CTX ctx;
-  if (!EVP_CipherInit_ex(ctx.get(), cipher, nullptr,
-                         reinterpret_cast<const uint8_t*>(raw_key.data()),
-                         iv.data(),
-                         mode == EncryptOrDecrypt::kEncrypt ? 1 : 0)) {
-    return OperationError;
-  }
-
-  // Encrypting needs a block size of space to allow for any padding.
-  output->resize(input.size() +
-                 (mode == EncryptOrDecrypt::kEncrypt ? iv.size() : 0));
-  int out_len;
-  if (!EVP_CipherUpdate(ctx.get(), output->data(), &out_len, input.data(),
-                        input.size()))
-    return OperationError;
-
-  // Write out the final block plus padding (if any) to the end of the data
-  // just written.
-  int tail_len;
-  if (!EVP_CipherFinal_ex(ctx.get(), output->data() + out_len, &tail_len))
-    return OperationError;
-
-  out_len += tail_len;
-  RTC_CHECK_LE(out_len, static_cast<int>(output->size()));
-  return Success;
-}
-
 int AesEncryptDecrypt(EncryptOrDecrypt mode,
                       webrtc::FrameCryptorTransformer::Algorithm algorithm,
                       const std::vector<uint8_t>& raw_key,
@@ -308,8 +268,9 @@ int AesEncryptDecrypt(EncryptOrDecrypt mode,
       return AesGcmEncryptDecrypt(
           mode, raw_key, data, tag_length_bits / 8, iv, additional_data, cipher, buffer);
     }
-    case webrtc::FrameCryptorTransformer::Algorithm::kAesCbc:
-      return AesCbcEncryptDecrypt(mode, raw_key, iv, data, buffer);
+    default:
+      RTC_LOG(LS_ERROR) << "Unsupported algorithm.";
+      return ErrorUnexpected;
   }
 }
 namespace webrtc {
@@ -724,8 +685,6 @@ uint8_t FrameCryptorTransformer::getIvSize() {
   switch (algorithm_) {
     case Algorithm::kAesGcm:
       return 12;
-    case Algorithm::kAesCbc:
-      return 16;
     default:
       return 0;
   }
diff --git a/sdk/android/api/org/webrtc/FrameCryptorAlgorithm.java b/sdk/android/api/org/webrtc/FrameCryptorAlgorithm.java
index d0d4dc8374..121656cc99 100644
--- a/sdk/android/api/org/webrtc/FrameCryptorAlgorithm.java
+++ b/sdk/android/api/org/webrtc/FrameCryptorAlgorithm.java
@@ -18,5 +18,4 @@
 
 public enum FrameCryptorAlgorithm {
   AES_GCM,
-  AES_CBC,
 }
\ No newline at end of file
diff --git a/sdk/android/src/jni/pc/frame_cryptor.cc b/sdk/android/src/jni/pc/frame_cryptor.cc
index af2fd8f2b0..33b938f7f4 100644
--- a/sdk/android/src/jni/pc/frame_cryptor.cc
+++ b/sdk/android/src/jni/pc/frame_cryptor.cc
@@ -103,8 +103,6 @@ webrtc::FrameCryptorTransformer::Algorithm AlgorithmFromIndex(int index) {
   switch (index) {
     case 0:
       return webrtc::FrameCryptorTransformer::Algorithm::kAesGcm;
-    case 1:
-      return webrtc::FrameCryptorTransformer::Algorithm::kAesCbc;
     default:
       return webrtc::FrameCryptorTransformer::Algorithm::kAesGcm;
   }
diff --git a/sdk/objc/api/peerconnection/RTCFrameCryptor.h b/sdk/objc/api/peerconnection/RTCFrameCryptor.h
index 864e55be95..43719f35d8 100644
--- a/sdk/objc/api/peerconnection/RTCFrameCryptor.h
+++ b/sdk/objc/api/peerconnection/RTCFrameCryptor.h
@@ -28,7 +28,6 @@ NS_ASSUME_NONNULL_BEGIN
 
 typedef NS_ENUM(NSUInteger, RTCCryptorAlgorithm) {
   RTCCryptorAlgorithmAesGcm = 0,
-  RTCCryptorAlgorithmAesCbc,
 };
 
 typedef NS_ENUM(NSInteger, FrameCryptionState) {
diff --git a/sdk/objc/api/peerconnection/RTCFrameCryptor.mm b/sdk/objc/api/peerconnection/RTCFrameCryptor.mm
index 7e6cd699d7..41893b086c 100644
--- a/sdk/objc/api/peerconnection/RTCFrameCryptor.mm
+++ b/sdk/objc/api/peerconnection/RTCFrameCryptor.mm
@@ -106,8 +106,6 @@ @implementation RTC_OBJC_TYPE (RTCFrameCryptor) {
   switch (algorithm) {
     case RTCCryptorAlgorithmAesGcm:
       return webrtc::FrameCryptorTransformer::Algorithm::kAesGcm;
-    case RTCCryptorAlgorithmAesCbc:
-      return webrtc::FrameCryptorTransformer::Algorithm::kAesCbc;
     default:
       return webrtc::FrameCryptorTransformer::Algorithm::kAesGcm;
   }