diff options
Diffstat (limited to 'third_party/bearssl/src/aes_big_cbcdec.c')
-rw-r--r-- | third_party/bearssl/src/aes_big_cbcdec.c | 69 |
1 files changed, 69 insertions, 0 deletions
diff --git a/third_party/bearssl/src/aes_big_cbcdec.c b/third_party/bearssl/src/aes_big_cbcdec.c new file mode 100644 index 0000000..d969a3b --- /dev/null +++ b/third_party/bearssl/src/aes_big_cbcdec.c @@ -0,0 +1,69 @@ +/* + * Copyright (c) 2016 Thomas Pornin <[email protected]> + * + * Permission is hereby granted, free of charge, to any person obtaining + * a copy of this software and associated documentation files (the + * "Software"), to deal in the Software without restriction, including + * without limitation the rights to use, copy, modify, merge, publish, + * distribute, sublicense, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include "inner.h" + +/* see bearssl_block.h */ +void +br_aes_big_cbcdec_init(br_aes_big_cbcdec_keys *ctx, + const void *key, size_t len) +{ + ctx->vtable = &br_aes_big_cbcdec_vtable; + ctx->num_rounds = br_aes_big_keysched_inv(ctx->skey, key, len); +} + +/* see bearssl_block.h */ +void +br_aes_big_cbcdec_run(const br_aes_big_cbcdec_keys *ctx, + void *iv, void *data, size_t len) +{ + unsigned char *buf, *ivbuf; + + ivbuf = iv; + buf = data; + while (len > 0) { + unsigned char tmp[16]; + int i; + + memcpy(tmp, buf, 16); + br_aes_big_decrypt(ctx->num_rounds, ctx->skey, buf); + for (i = 0; i < 16; i ++) { + buf[i] ^= ivbuf[i]; + } + memcpy(ivbuf, tmp, 16); + buf += 16; + len -= 16; + } +} + +/* see bearssl_block.h */ +const br_block_cbcdec_class br_aes_big_cbcdec_vtable = { + sizeof(br_aes_big_cbcdec_keys), + 16, + 4, + (void (*)(const br_block_cbcdec_class **, const void *, size_t)) + &br_aes_big_cbcdec_init, + (void (*)(const br_block_cbcdec_class *const *, void *, void *, size_t)) + &br_aes_big_cbcdec_run +}; |