1 /* $OpenBSD: e_chacha.c,v 1.5 2014/08/04 04:16:11 miod Exp $ */ 2 /* 3 * Copyright (c) 2014 Joel Sing <jsing@openbsd.org> 4 * 5 * Permission to use, copy, modify, and distribute this software for any 6 * purpose with or without fee is hereby granted, provided that the above 7 * copyright notice and this permission notice appear in all copies. 8 * 9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16 */ 17 18 #include <openssl/opensslconf.h> 19 20 #ifndef OPENSSL_NO_CHACHA 21 22 #include <openssl/chacha.h> 23 #include <openssl/evp.h> 24 #include <openssl/objects.h> 25 26 #include "evp_locl.h" 27 28 static int chacha_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out, 29 const unsigned char *in, size_t len); 30 static int chacha_init(EVP_CIPHER_CTX *ctx, const unsigned char *key, 31 const unsigned char *iv, int enc); 32 33 static const EVP_CIPHER chacha20_cipher = { 34 .nid = NID_chacha20, 35 .block_size = 1, 36 .key_len = 32, 37 .iv_len = 8, 38 .flags = EVP_CIPH_STREAM_CIPHER, 39 .init = chacha_init, 40 .do_cipher = chacha_cipher, 41 .ctx_size = sizeof(ChaCha_ctx) 42 }; 43 44 const EVP_CIPHER * 45 EVP_chacha20(void) 46 { 47 return (&chacha20_cipher); 48 } 49 50 static int 51 chacha_init(EVP_CIPHER_CTX *ctx, const unsigned char *key, 52 const unsigned char *iv, int enc) 53 { 54 ChaCha_set_key((ChaCha_ctx *)ctx->cipher_data, key, 55 EVP_CIPHER_CTX_key_length(ctx) * 8); 56 if (iv != NULL) 57 ChaCha_set_iv((ChaCha_ctx *)ctx->cipher_data, iv, NULL); 58 return 1; 59 } 60 61 static int 62 chacha_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out, const unsigned char *in, 63 size_t len) 64 { 65 ChaCha((ChaCha_ctx *)ctx->cipher_data, out, in, len); 66 return 1; 67 } 68 69 #endif 70