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Diffstat (limited to 'vendor/maunium.net/go/mautrix/crypto/aescbc/aes_cbc.go')
-rw-r--r--vendor/maunium.net/go/mautrix/crypto/aescbc/aes_cbc.go60
1 files changed, 60 insertions, 0 deletions
diff --git a/vendor/maunium.net/go/mautrix/crypto/aescbc/aes_cbc.go b/vendor/maunium.net/go/mautrix/crypto/aescbc/aes_cbc.go
new file mode 100644
index 0000000..d69a5f4
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+++ b/vendor/maunium.net/go/mautrix/crypto/aescbc/aes_cbc.go
@@ -0,0 +1,60 @@
+// Copyright (c) 2024 Sumner Evans
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+package aescbc
+
+import (
+	"crypto/aes"
+	"crypto/cipher"
+
+	"maunium.net/go/mautrix/crypto/pkcs7"
+)
+
+// Encrypt encrypts the plaintext with the key and IV. The IV length must be
+// equal to the AES block size.
+//
+// This function might mutate the plaintext.
+func Encrypt(key, iv, plaintext []byte) ([]byte, error) {
+	if len(key) == 0 {
+		return nil, ErrNoKeyProvided
+	}
+	if len(iv) != aes.BlockSize {
+		return nil, ErrIVNotBlockSize
+	}
+	plaintext = pkcs7.Pad(plaintext, aes.BlockSize)
+
+	block, err := aes.NewCipher(key)
+	if err != nil {
+		return nil, err
+	}
+
+	cipher.NewCBCEncrypter(block, iv).CryptBlocks(plaintext, plaintext)
+	return plaintext, nil
+}
+
+// Decrypt decrypts the ciphertext with the key and IV. The IV length must be
+// equal to the block size.
+//
+// This function mutates the ciphertext.
+func Decrypt(key, iv, ciphertext []byte) ([]byte, error) {
+	if len(key) == 0 {
+		return nil, ErrNoKeyProvided
+	}
+	if len(iv) != aes.BlockSize {
+		return nil, ErrIVNotBlockSize
+	}
+
+	block, err := aes.NewCipher(key)
+	if err != nil {
+		return nil, err
+	}
+	if len(ciphertext) < aes.BlockSize {
+		return nil, ErrNotMultipleBlockSize
+	}
+
+	cipher.NewCBCDecrypter(block, iv).CryptBlocks(ciphertext, ciphertext)
+	return pkcs7.Unpad(ciphertext), nil
+}