diff options
Diffstat (limited to 'lib/crypto/arcfour.c')
-rw-r--r-- | lib/crypto/arcfour.c | 91 |
1 files changed, 91 insertions, 0 deletions
diff --git a/lib/crypto/arcfour.c b/lib/crypto/arcfour.c new file mode 100644 index 0000000000..c57e05d0e9 --- /dev/null +++ b/lib/crypto/arcfour.c @@ -0,0 +1,91 @@ +/* + Unix SMB/CIFS implementation. + + An implementation of the arcfour algorithm + + Copyright (C) Andrew Tridgell 1998 + + This program 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 3 of the License, or + (at your option) any later version. + + This program 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, see <http://www.gnu.org/licenses/>. +*/ + +#include "includes.h" +#include "../lib/crypto/arcfour.h" + +/* initialise the arcfour sbox with key */ +_PUBLIC_ void arcfour_init(struct arcfour_state *state, const DATA_BLOB *key) +{ + int ind; + uint8_t j = 0; + for (ind = 0; ind < sizeof(state->sbox); ind++) { + state->sbox[ind] = (uint8_t)ind; + } + + for (ind = 0; ind < sizeof(state->sbox); ind++) { + uint8_t tc; + + j += (state->sbox[ind] + key->data[ind%key->length]); + + tc = state->sbox[ind]; + state->sbox[ind] = state->sbox[j]; + state->sbox[j] = tc; + } + state->index_i = 0; + state->index_j = 0; +} + +/* crypt the data with arcfour */ +_PUBLIC_ void arcfour_crypt_sbox(struct arcfour_state *state, uint8_t *data, int len) +{ + int ind; + + for (ind = 0; ind < len; ind++) { + uint8_t tc; + uint8_t t; + + state->index_i++; + state->index_j += state->sbox[state->index_i]; + + tc = state->sbox[state->index_i]; + state->sbox[state->index_i] = state->sbox[state->index_j]; + state->sbox[state->index_j] = tc; + + t = state->sbox[state->index_i] + state->sbox[state->index_j]; + data[ind] = data[ind] ^ state->sbox[t]; + } +} + +/* + arcfour encryption with a blob key +*/ +_PUBLIC_ void arcfour_crypt_blob(uint8_t *data, int len, const DATA_BLOB *key) +{ + struct arcfour_state state; + arcfour_init(&state, key); + arcfour_crypt_sbox(&state, data, len); +} + +/* + a variant that assumes a 16 byte key. This should be removed + when the last user is gone +*/ +_PUBLIC_ void arcfour_crypt(uint8_t *data, const uint8_t keystr[16], int len) +{ + DATA_BLOB key = data_blob(keystr, 16); + + arcfour_crypt_blob(data, len, &key); + + data_blob_free(&key); +} + + |