diff options
Diffstat (limited to 'lib/crypto/crypto_aesctr.c')
| -rw-r--r-- | lib/crypto/crypto_aesctr.c | 123 |
1 files changed, 0 insertions, 123 deletions
diff --git a/lib/crypto/crypto_aesctr.c b/lib/crypto/crypto_aesctr.c deleted file mode 100644 index bc7479c..0000000 --- a/lib/crypto/crypto_aesctr.c +++ /dev/null @@ -1,123 +0,0 @@ -/*- - * Copyright 2007-2009 Colin Percival - * All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * - * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND - * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE - * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE - * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE - * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL - * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS - * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) - * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT - * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY - * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF - * SUCH DAMAGE. - * - * This file was originally written by Colin Percival as part of the Tarsnap - * online backup system. - */ - -#include <stdint.h> -#include <stdlib.h> - -#include <openssl/aes.h> - -#include "sysendian.h" - -#include "crypto_aesctr.h" - -struct crypto_aesctr { - AES_KEY * key; - uint64_t nonce; - uint64_t bytectr; - uint8_t buf[16]; -}; - -/** - * crypto_aesctr_init(key, nonce): - * Prepare to encrypt/decrypt data with AES in CTR mode, using the provided - * expanded key and nonce. The key provided must remain valid for the - * lifetime of the stream. - */ -struct crypto_aesctr * -crypto_aesctr_init(AES_KEY * key, uint64_t nonce) -{ - struct crypto_aesctr * stream; - - /* Allocate memory. */ - if ((stream = malloc(sizeof(struct crypto_aesctr))) == NULL) - goto err0; - - /* Initialize values. */ - stream->key = key; - stream->nonce = nonce; - stream->bytectr = 0; - - /* Success! */ - return (stream); - -err0: - /* Failure! */ - return (NULL); -} - -/** - * crypto_aesctr_stream(stream, inbuf, outbuf, buflen): - * Generate the next ${buflen} bytes of the AES-CTR stream and xor them with - * bytes from ${inbuf}, writing the result into ${outbuf}. If the buffers - * ${inbuf} and ${outbuf} overlap, they must be identical. - */ -void -crypto_aesctr_stream(struct crypto_aesctr * stream, const uint8_t * inbuf, - uint8_t * outbuf, size_t buflen) -{ - uint8_t pblk[16]; - size_t pos; - int bytemod; - - for (pos = 0; pos < buflen; pos++) { - /* How far through the buffer are we? */ - bytemod = stream->bytectr % 16; - - /* Generate a block of cipherstream if needed. */ - if (bytemod == 0) { - be64enc(pblk, stream->nonce); - be64enc(pblk + 8, stream->bytectr / 16); - AES_encrypt(pblk, stream->buf, stream->key); - } - - /* Encrypt a byte. */ - outbuf[pos] = inbuf[pos] ^ stream->buf[bytemod]; - - /* Move to the next byte of cipherstream. */ - stream->bytectr += 1; - } -} - -/** - * crypto_aesctr_free(stream): - * Free the provided stream object. - */ -void -crypto_aesctr_free(struct crypto_aesctr * stream) -{ - int i; - - /* Zero potentially sensitive information. */ - for (i = 0; i < 16; i++) - stream->buf[i] = 0; - stream->bytectr = stream->nonce = 0; - - /* Free the stream. */ - free(stream); -} |