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thirdparty/salsa20/salsa20.h

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+/*
+BASED ON salsa20-ref.c version 20051118
+original author: D. J. Bernstein
+Public domain.
+*/
+
+#pragma once
+
+#include <cstdint>
+
+struct salsa20_ctx
+{
+    uint32_t m_input[16];
+};
+
+/*
+ * Initializes the context with the chosen key.
+ * 
+ * ctx: The context to initialize.
+ * key: A pointer to the key bytes.
+ * keySize: The length of the key in bits. Has to be 128 or 256.
+ */
+void Salsa20_KeySetup(salsa20_ctx* ctx, const uint8_t* key, uint32_t keySize);
+
+/*
+ * Initializes or changes the IV of the context.
+ * Can be called multiple times on the same context in order to encrypt/decrypt messages with the same key but different IV's.
+ * 
+ * ctx: The context to initialize.
+ * iv: A pointer to the IV bytes. Must be 64 bits long.
+ */
+void Salsa20_IVSetup(salsa20_ctx* ctx, const uint8_t* iv);
+
+/*
+ * Encrypts the specified amount of plain text and writes it to the cipher text buffer.
+ * The cipher text buffer and the plain text buffer can be the same.
+ * 
+ * ctx: The context that was previously initialized with a key and IV.
+ * cipherText: A pointer to the cipher text buffer which must at least be msgLen bytes.
+ * plainText: A pointer to the plain text buffer which must at least be msgLen bytes.
+ * msgLen: The amount of bytes to encrypt.
+ */
+void Salsa20_Encrypt_Bytes(salsa20_ctx* ctx, const uint8_t* plainText, uint8_t* cipherText, uint32_t msgLen);
+
+/*
+ * Decrypts the specified amount of cipher text and writes it to the plain text buffer.
+ * The cipher text buffer and the plain text buffer can be the same.
+ * Internally just calls the encryption method.
+ * 
+ * ctx: The context that was previously initialized with a key and IV.
+ * cipherText: A pointer to the cipher text buffer which must at least be msgLen bytes.
+ * plainText: A pointer to the plain text buffer which must at least be msgLen bytes.
+ * msgLen: The amount of bytes to decrypt.
+ */
+void Salsa20_Decrypt_Bytes(salsa20_ctx* ctx, const uint8_t* cipherText, uint8_t* plainText, uint32_t msgLen);