freebsd-dev/sys/crypto/rc5/rc5_cbc.c
Yoshinobu Inoue 6a800098cc IPSEC support in the kernel.
pr_input() routines prototype is also changed to support IPSEC and IPV6
chained protocol headers.

Reviewed by: freebsd-arch, cvs-committers
Obtained from: KAME project
1999-12-22 19:13:38 +00:00

212 lines
4.7 KiB
C

/*
* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
* 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.
* 3. Neither the name of the project nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE PROJECT 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 PROJECT 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.
*
* $FreeBSD$
*/
/*
* based on sys/crypto/des/des_cbc.c, rewrote by Tomomi Suzuki
*/
#include <crypto/rc5/rc5.h>
void
rc5_cbc_process(m0, skip, length, e_key, iv, mode)
struct mbuf *m0;
size_t skip;
size_t length;
RC5_WORD *e_key;
u_int8_t *iv;
int mode;
{
u_int8_t inbuf[8], outbuf[8];
struct mbuf *m;
size_t off;
/* sanity check */
if (m0->m_pkthdr.len < skip) {
printf("rc5_cbc_process: mbuf length < skip\n");
return;
}
if (m0->m_pkthdr.len < length) {
printf("rc5_cbc_process: mbuf length < encrypt length\n");
return;
}
if (m0->m_pkthdr.len < skip + length) {
printf("rc5_cbc_process: mbuf length < "
"skip + encrypt length\n");
return;
}
if (length % 8) {
printf("rc5_cbc_process: length(%lu)is not multipleof 8\n",
(u_long)length);
return;
}
m = m0;
off = 0;
/* skip over the header */
while (skip) {
if (!m)
panic("rc5_cbc_process: mbuf chain?\n");
if (m->m_len <= skip) {
skip -= m->m_len;
m = m->m_next;
off = 0;
} else {
off = skip;
skip = 0;
}
}
/* copy iv into outbuf for XOR (encrypt) */
bcopy(iv, outbuf, 8);
/*
* encrypt/decrypt packet
*/
while (length > 0) {
int i;
if (!m)
panic("rc5_cbc_process: mbuf chain?\n");
/*
* copy the source into input buffer.
* don't update off or m, since we need to use them
* later.
*/
if (off + 8 <= m->m_len)
bcopy(mtod(m, u_int8_t *) + off, &inbuf[0], 8);
else {
struct mbuf *n;
size_t noff;
u_int8_t *p;
u_int8_t *in;
n = m;
noff = off;
p = mtod(n, u_int8_t *) + noff;
in = &inbuf[0];
while (in - &inbuf[0] < 8) {
if (!p) {
panic("rc5_cbc_process: "
"mbuf chain?\n");
}
*in++ = *p++;
noff++;
if (noff < n->m_len)
continue;
do {
n = n->m_next;
} while (n && !n->m_len);
noff = 0;
if (n)
p = mtod(n, u_int8_t *) + noff;
else
p = NULL;
}
}
/* encrypt/decrypt */
switch (mode) {
case RC5_ENCRYPT:
/* XOR */
for (i = 0; i < 8; i++)
inbuf[i] ^= outbuf[i];
/* encrypt */
rc5_encrypt_round16(outbuf, inbuf, e_key);
break;
case RC5_DECRYPT:
/* decrypt */
rc5_decrypt_round16(outbuf, inbuf, e_key);
/* XOR */
for (i = 0; i < 8; i++)
outbuf[i] ^= iv[i];
/* copy inbuf into iv for next XOR */
bcopy(inbuf, iv, 8);
break;
}
/*
* copy the output buffer into the result.
* need to update off and m.
*/
if (off + 8 < m->m_len) {
bcopy(&outbuf[0], mtod(m, u_int8_t *) + off, 8);
off += 8;
} else if (off + 8 == m->m_len) {
bcopy(&outbuf[0], mtod(m, u_int8_t *) + off, 8);
do {
m = m->m_next;
} while (m && !m->m_len);
off = 0;
} else {
struct mbuf *n;
size_t noff;
u_int8_t *p;
u_int8_t *out;
n = m;
noff = off;
p = mtod(n, u_int8_t *) + noff;
out = &outbuf[0];
while (out - &outbuf[0] < 8) {
if (!p) {
panic("rc5_cbc_process: "
"mbuf chain?\n");
}
*p++ = *out++;
noff++;
if (noff < n->m_len)
continue;
do {
n = n->m_next;
} while (n && !n->m_len);
noff = 0;
if (n)
p = mtod(n, u_int8_t *) + noff;
else
p = NULL;
}
m = n;
off = noff;
}
length -= 8;
}
}