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author | archie <archie@FreeBSD.org> | 2000-04-09 21:01:01 +0000 |
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committer | archie <archie@FreeBSD.org> | 2000-04-09 21:01:01 +0000 |
commit | 5bb79e5ce88c18dac26d6fc6db0eabf87ce998e6 (patch) | |
tree | 9aecf7e6671dba2ca95ba550e03f39b70c284e13 /sys | |
parent | a06297ebe60ed750cf630e6c3fe49cdfea80b8cc (diff) | |
download | FreeBSD-src-5bb79e5ce88c18dac26d6fc6db0eabf87ce998e6.zip FreeBSD-src-5bb79e5ce88c18dac26d6fc6db0eabf87ce998e6.tar.gz |
A simplified RC4 implementation for kernel use.
Diffstat (limited to 'sys')
-rw-r--r-- | sys/crypto/rc4/rc4.c | 104 | ||||
-rw-r--r-- | sys/crypto/rc4/rc4.h | 54 |
2 files changed, 158 insertions, 0 deletions
diff --git a/sys/crypto/rc4/rc4.c b/sys/crypto/rc4/rc4.c new file mode 100644 index 0000000..5cea08a --- /dev/null +++ b/sys/crypto/rc4/rc4.c @@ -0,0 +1,104 @@ + +/* + * rc4.c + * + * Copyright (c) 1996-2000 Whistle Communications, Inc. + * All rights reserved. + * + * Subject to the following obligations and disclaimer of warranty, use and + * redistribution of this software, in source or object code forms, with or + * without modifications are expressly permitted by Whistle Communications; + * provided, however, that: + * 1. Any and all reproductions of the source or object code must include the + * copyright notice above and the following disclaimer of warranties; and + * 2. No rights are granted, in any manner or form, to use Whistle + * Communications, Inc. trademarks, including the mark "WHISTLE + * COMMUNICATIONS" on advertising, endorsements, or otherwise except as + * such appears in the above copyright notice or in the software. + * + * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND + * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO + * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, + * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. + * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY + * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS + * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. + * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES + * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING + * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, + * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR + * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER 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 WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY + * OF SUCH DAMAGE. + * + * $FreeBSD$ + */ + +#include <sys/types.h> +#include <crypto/rc4/rc4.h> + +static __inline void +swap_bytes(u_char *a, u_char *b) +{ + u_char temp; + + temp = *a; + *a = *b; + *b = temp; +} + +/* + * Initialize an RC4 state buffer using the supplied key, + * which can have arbitrary length. + */ +void +rc4_init(struct rc4_state *const state, const u_char *key, int keylen) +{ + u_char j; + int i; + + /* Initialize state with identity permutation */ + for (i = 0; i < 256; i++) + state->perm[i] = (u_char)i; + state->index1 = 0; + state->index2 = 0; + + /* Randomize the permutation using key data */ + for (j = i = 0; i < 256; i++) { + j += state->perm[i] + key[i % keylen]; + swap_bytes(&state->perm[i], &state->perm[j]); + } +} + +/* + * Encrypt some data using the supplied RC4 state buffer. + * The input and output buffers may be the same buffer. + * Since RC4 is a stream cypher, this function is used + * for both encryption and decryption. + */ +void +rc4_crypt(struct rc4_state *const state, + const u_char *inbuf, u_char *outbuf, int buflen) +{ + int i; + u_char j; + + for (i = 0; i < buflen; i++) { + + /* Update modification indicies */ + state->index1++; + state->index2 += state->perm[state->index1]; + + /* Modify permutation */ + swap_bytes(&state->perm[state->index1], + &state->perm[state->index2]); + + /* Encrypt/decrypt next byte */ + j = state->perm[state->index1] + state->perm[state->index2]; + outbuf[i] = inbuf[i] ^ state->perm[j]; + } +} + diff --git a/sys/crypto/rc4/rc4.h b/sys/crypto/rc4/rc4.h new file mode 100644 index 0000000..670b1a0 --- /dev/null +++ b/sys/crypto/rc4/rc4.h @@ -0,0 +1,54 @@ + +/* + * rc4.h + * + * Copyright (c) 1996-2000 Whistle Communications, Inc. + * All rights reserved. + * + * Subject to the following obligations and disclaimer of warranty, use and + * redistribution of this software, in source or object code forms, with or + * without modifications are expressly permitted by Whistle Communications; + * provided, however, that: + * 1. Any and all reproductions of the source or object code must include the + * copyright notice above and the following disclaimer of warranties; and + * 2. No rights are granted, in any manner or form, to use Whistle + * Communications, Inc. trademarks, including the mark "WHISTLE + * COMMUNICATIONS" on advertising, endorsements, or otherwise except as + * such appears in the above copyright notice or in the software. + * + * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND + * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO + * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, + * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. + * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY + * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS + * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. + * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES + * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING + * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, + * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR + * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER 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 WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY + * OF SUCH DAMAGE. + * + * $FreeBSD$ + */ + +#ifndef _SYS_CRYPTO_RC4_RC4_H_ +#define _SYS_CRYPTO_RC4_RC4_H_ + +struct rc4_state { + u_char perm[256]; + u_char index1; + u_char index2; +}; + +extern void rc4_init(struct rc4_state *state, const u_char *key, int keylen); +extern void rc4_crypt(struct rc4_state *state, + const u_char *inbuf, u_char *outbuf, int buflen); + +#endif + |