Important changes to repositories hosted on mbed.com
Mbed hosted mercurial repositories are deprecated and are due to be permanently deleted in July 2026.
To keep a copy of this software download the repository Zip archive or clone locally using Mercurial.
It is also possible to export all your personal repositories from the account settings page.
Diff: wolfcrypt/src/chacha20_poly1305.c
- Revision:
- 17:ff9d1e86ad5f
- Parent:
- 16:048e5e270a58
diff -r 048e5e270a58 -r ff9d1e86ad5f wolfcrypt/src/chacha20_poly1305.c --- a/wolfcrypt/src/chacha20_poly1305.c Tue Nov 19 14:32:16 2019 +0000 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,252 +0,0 @@ -/* chacha.c - * - * Copyright (C) 2006-2017 wolfSSL Inc. - * - * This file is part of wolfSSL. - * - * wolfSSL is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * wolfSSL is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335, USA - */ - - - -#ifdef HAVE_CONFIG_H - #include <config.h> -#endif - -#include <wolfssl/wolfcrypt/settings.h> - -#if defined(HAVE_CHACHA) && defined(HAVE_POLY1305) - -#include <wolfssl/wolfcrypt/chacha20_poly1305.h> -#include <wolfssl/wolfcrypt/error-crypt.h> -#include <wolfssl/wolfcrypt/logging.h> -#include <wolfssl/wolfcrypt/chacha.h> -#include <wolfssl/wolfcrypt/poly1305.h> - -#ifdef NO_INLINE -#include <wolfssl/wolfcrypt/misc.h> -#else -#define WOLFSSL_MISC_INCLUDED -#include <wolfcrypt/src/misc.c> -#endif - -#ifdef CHACHA_AEAD_TEST -#include <stdio.h> -#endif - -#define CHACHA20_POLY1305_AEAD_INITIAL_COUNTER 0 -#define CHACHA20_POLY1305_MAC_PADDING_ALIGNMENT 16 - -static void word32ToLittle64(const word32 inLittle32, byte outLittle64[8]); -static int calculateAuthTag( - const byte inAuthKey[CHACHA20_POLY1305_AEAD_KEYSIZE], - const byte* inAAD, const word32 inAADLen, - const byte *inCiphertext, const word32 inCiphertextLen, - byte outAuthTag[CHACHA20_POLY1305_AEAD_AUTHTAG_SIZE]); - -int wc_ChaCha20Poly1305_Encrypt( - const byte inKey[CHACHA20_POLY1305_AEAD_KEYSIZE], - const byte inIV[CHACHA20_POLY1305_AEAD_IV_SIZE], - const byte* inAAD, const word32 inAADLen, - const byte* inPlaintext, const word32 inPlaintextLen, - byte* outCiphertext, - byte outAuthTag[CHACHA20_POLY1305_AEAD_AUTHTAG_SIZE]) -{ - int err; - byte poly1305Key[CHACHA20_POLY1305_AEAD_KEYSIZE]; - ChaCha chaChaCtx; - - /* Validate function arguments */ - - if (!inKey || !inIV || - !inPlaintext || !inPlaintextLen || - !outCiphertext || - !outAuthTag) - { - return BAD_FUNC_ARG; - } - - XMEMSET(poly1305Key, 0, sizeof(poly1305Key)); - - /* Create the Poly1305 key */ - err = wc_Chacha_SetKey(&chaChaCtx, inKey, CHACHA20_POLY1305_AEAD_KEYSIZE); - if (err != 0) return err; - - err = wc_Chacha_SetIV(&chaChaCtx, inIV, - CHACHA20_POLY1305_AEAD_INITIAL_COUNTER); - if (err != 0) return err; - - err = wc_Chacha_Process(&chaChaCtx, poly1305Key, poly1305Key, - CHACHA20_POLY1305_AEAD_KEYSIZE); - if (err != 0) return err; - - /* Encrypt the plaintext using ChaCha20 */ - err = wc_Chacha_Process(&chaChaCtx, outCiphertext, inPlaintext, - inPlaintextLen); - /* Calculate the Poly1305 auth tag */ - if (err == 0) - err = calculateAuthTag(poly1305Key, - inAAD, inAADLen, - outCiphertext, inPlaintextLen, - outAuthTag); - ForceZero(poly1305Key, sizeof(poly1305Key)); - - return err; -} - - -int wc_ChaCha20Poly1305_Decrypt( - const byte inKey[CHACHA20_POLY1305_AEAD_KEYSIZE], - const byte inIV[CHACHA20_POLY1305_AEAD_IV_SIZE], - const byte* inAAD, const word32 inAADLen, - const byte* inCiphertext, const word32 inCiphertextLen, - const byte inAuthTag[CHACHA20_POLY1305_AEAD_AUTHTAG_SIZE], - byte* outPlaintext) -{ - int err; - byte poly1305Key[CHACHA20_POLY1305_AEAD_KEYSIZE]; - ChaCha chaChaCtx; - byte calculatedAuthTag[CHACHA20_POLY1305_AEAD_AUTHTAG_SIZE]; - - /* Validate function arguments */ - - if (!inKey || !inIV || - !inCiphertext || !inCiphertextLen || - !inAuthTag || - !outPlaintext) - { - return BAD_FUNC_ARG; - } - - XMEMSET(calculatedAuthTag, 0, sizeof(calculatedAuthTag)); - XMEMSET(poly1305Key, 0, sizeof(poly1305Key)); - - /* Create the Poly1305 key */ - err = wc_Chacha_SetKey(&chaChaCtx, inKey, CHACHA20_POLY1305_AEAD_KEYSIZE); - if (err != 0) return err; - - err = wc_Chacha_SetIV(&chaChaCtx, inIV, - CHACHA20_POLY1305_AEAD_INITIAL_COUNTER); - if (err != 0) return err; - - err = wc_Chacha_Process(&chaChaCtx, poly1305Key, poly1305Key, - CHACHA20_POLY1305_AEAD_KEYSIZE); - if (err != 0) return err; - - /* Calculate the Poly1305 auth tag */ - err = calculateAuthTag(poly1305Key, - inAAD, inAADLen, - inCiphertext, inCiphertextLen, - calculatedAuthTag); - - /* Compare the calculated auth tag with the received one */ - if (err == 0 && ConstantCompare(inAuthTag, calculatedAuthTag, - CHACHA20_POLY1305_AEAD_AUTHTAG_SIZE) != 0) - { - err = MAC_CMP_FAILED_E; - } - - /* Decrypt the received ciphertext */ - if (err == 0) - err = wc_Chacha_Process(&chaChaCtx, outPlaintext, inCiphertext, - inCiphertextLen); - ForceZero(poly1305Key, sizeof(poly1305Key)); - - return err; -} - - -static int calculateAuthTag( - const byte inAuthKey[CHACHA20_POLY1305_AEAD_KEYSIZE], - const byte *inAAD, const word32 inAADLen, - const byte *inCiphertext, const word32 inCiphertextLen, - byte outAuthTag[CHACHA20_POLY1305_AEAD_AUTHTAG_SIZE]) -{ - int err; - Poly1305 poly1305Ctx; - byte padding[CHACHA20_POLY1305_MAC_PADDING_ALIGNMENT - 1]; - word32 paddingLen; - byte little64[16]; - - XMEMSET(padding, 0, sizeof(padding)); - - /* Initialize Poly1305 */ - err = wc_Poly1305SetKey(&poly1305Ctx, inAuthKey, - CHACHA20_POLY1305_AEAD_KEYSIZE); - if (err) - return err; - - /* Create the authTag by MAC'ing the following items: */ - /* -- AAD */ - if (inAAD && inAADLen) - { - err = wc_Poly1305Update(&poly1305Ctx, inAAD, inAADLen); - /* -- padding1: pad the AAD to 16 bytes */ - paddingLen = -(int)inAADLen & - (CHACHA20_POLY1305_MAC_PADDING_ALIGNMENT - 1); - if (paddingLen) - err += wc_Poly1305Update(&poly1305Ctx, padding, paddingLen); - - if (err) - return err; - } - - /* -- Ciphertext */ - err = wc_Poly1305Update(&poly1305Ctx, inCiphertext, inCiphertextLen); - if (err) - return err; - - /* -- padding2: pad the ciphertext to 16 bytes */ - paddingLen = -(int)inCiphertextLen & - (CHACHA20_POLY1305_MAC_PADDING_ALIGNMENT - 1); - if (paddingLen) - { - err = wc_Poly1305Update(&poly1305Ctx, padding, paddingLen); - if (err) - return err; - } - - /* -- AAD length as a 64-bit little endian integer */ - word32ToLittle64(inAADLen, little64); - /* -- Ciphertext length as a 64-bit little endian integer */ - word32ToLittle64(inCiphertextLen, little64 + 8); - err = wc_Poly1305Update(&poly1305Ctx, little64, sizeof(little64)); - if (err) - return err; - - /* Finalize the auth tag */ - err = wc_Poly1305Final(&poly1305Ctx, outAuthTag); - - return err; -} - - -static void word32ToLittle64(const word32 inLittle32, byte outLittle64[8]) -{ -#ifndef WOLFSSL_X86_64_BUILD - XMEMSET(outLittle64 + 4, 0, 4); - - outLittle64[0] = (byte)(inLittle32 & 0x000000FF); - outLittle64[1] = (byte)((inLittle32 & 0x0000FF00) >> 8); - outLittle64[2] = (byte)((inLittle32 & 0x00FF0000) >> 16); - outLittle64[3] = (byte)((inLittle32 & 0xFF000000) >> 24); -#else - *(word64*)outLittle64 = inLittle32; -#endif -} - - -#endif /* HAVE_CHACHA && HAVE_POLY1305 */ -