diff options
Diffstat (limited to 'sys/crypto/cast128/cast128_cbc.c')
-rw-r--r-- | sys/crypto/cast128/cast128_cbc.c | 219 |
1 files changed, 219 insertions, 0 deletions
diff --git a/sys/crypto/cast128/cast128_cbc.c b/sys/crypto/cast128/cast128_cbc.c new file mode 100644 index 0000000..1dfe2d8 --- /dev/null +++ b/sys/crypto/cast128/cast128_cbc.c @@ -0,0 +1,219 @@ +/* + * 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 <sys/param.h> +#include <sys/systm.h> +#include <sys/mbuf.h> +#include <crypto/cast128/cast128.h> + + +void +cast128_cbc_process(m0, skip, length, subkey, iv, keylen, mode) + struct mbuf *m0; + size_t skip; + size_t length; + u_int32_t *subkey; + u_int8_t *iv; + size_t keylen; + int mode; +{ + struct mbuf *m; + u_int8_t inbuf[8], outbuf[8]; + size_t off; + + /* sanity check */ + if (m0->m_pkthdr.len < skip) { + printf("cast128_cbc_process: mbuf length < skip\n"); + return; + } + if (m0->m_pkthdr.len < length) { + printf("cast128_cbc_process: mbuf length < encrypt length\n"); + return; + } + if (m0->m_pkthdr.len < skip + length) { + printf("cast128_cbc_process: " + "mbuf length < skip + encrypt length\n"); + return; + } + if (length % 8) { + printf("cast128_cbc_process: length is not multiple of 8\n"); + return; + } + + m = m0; + off = 0; + + /* skip over the header */ + while (skip) { + if (!m) + panic("cast128_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("cast128_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, 8); + else { + struct mbuf *n; + size_t noff; + u_int8_t *p, *in; + + n = m; + noff = off; + p = mtod(n, u_int8_t *) + noff; + + in = inbuf; + while (in - inbuf < 8) { + if (!p) { + panic("cast128_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 *); + else + p = NULL; + } + } + + /* encrypt/decrypt */ + switch (mode) { + case CAST128_ENCRYPT: + /* XOR */ + for (i = 0; i < 8; i++) + inbuf[i] ^= outbuf[i]; + + /* encrypt */ + if (keylen <= 80/8) + cast128_encrypt_round12(outbuf, inbuf, subkey); + else + cast128_encrypt_round16(outbuf, inbuf, subkey); + break; + + case CAST128_DECRYPT: + /* decrypt */ + if (keylen <= 80/8) + cast128_decrypt_round12(outbuf, inbuf, subkey); + else + cast128_decrypt_round16(outbuf, inbuf, subkey); + + /* 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, mtod(m, u_int8_t *) + off, 8); + off += 8; + } else if (off + 8 == m->m_len) { + bcopy(outbuf, 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, *out; + + n = m; + noff = off; + p = mtod(n, u_int8_t *) + noff; + + out = outbuf; + while (out - outbuf < 8) { + if (!p) { + panic("cast128_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 *); + else + p = NULL; + } + + m = n; + off = noff; + } + + length -= 8; + } +} + |