diff options
Diffstat (limited to 'crypto/kerberosIV/lib/krb/mk_safe.c')
-rw-r--r-- | crypto/kerberosIV/lib/krb/mk_safe.c | 131 |
1 files changed, 131 insertions, 0 deletions
diff --git a/crypto/kerberosIV/lib/krb/mk_safe.c b/crypto/kerberosIV/lib/krb/mk_safe.c new file mode 100644 index 0000000..df5ca21 --- /dev/null +++ b/crypto/kerberosIV/lib/krb/mk_safe.c @@ -0,0 +1,131 @@ +/* + * Copyright (c) 1995, 1996, 1997 Kungliga Tekniska Högskolan + * (Royal Institute of Technology, Stockholm, Sweden). + * 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. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the Kungliga Tekniska + * Högskolan and its contributors. + * + * 4. Neither the name of the Institute 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 INSTITUTE 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 INSTITUTE 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. + */ + +#include "krb_locl.h" + +RCSID("$Id: mk_safe.c,v 1.21 1997/04/19 23:18:03 joda Exp $"); + +/* application include files */ +#include "lsb_addr_comp.h" + + +/* from rd_safe.c */ +extern int dqc_type; +void fixup_quad_cksum(void*, size_t, des_cblock*, void*, void*, int); + +/* + * krb_mk_safe() constructs an AUTH_MSG_SAFE message. It takes some + * user data "in" of "length" bytes and creates a packet in "out" + * consisting of the user data, a timestamp, and the sender's network + * address, followed by a checksum computed on the above, using the + * given "key". The length of the resulting packet is returned. + * + * The "out" packet consists of: + * + * Size Variable Field + * ---- -------- ----- + * + * 1 byte KRB_PROT_VERSION protocol version number + * 1 byte AUTH_MSG_SAFE | message type plus local + * HOST_BYTE_ORDER byte order in low bit + * + * ===================== begin checksum ================================ + * + * 4 bytes length length of user data + * length in user data + * 1 byte msg_time_5ms timestamp milliseconds + * 4 bytes sender->sin.addr.s_addr sender's IP address + * + * 4 bytes msg_time_sec or timestamp seconds with + * -msg_time_sec direction in sign bit + * + * ======================= end checksum ================================ + * + * 16 bytes big_cksum quadratic checksum of + * above using "key" + */ + +int32_t +krb_mk_safe(void *in, void *out, u_int32_t length, des_cblock *key, + struct sockaddr_in *sender, struct sockaddr_in *receiver) +{ + unsigned char * p = (unsigned char*)out; + struct timeval tv; + unsigned char *start; + u_int32_t src_addr; + + p += krb_put_int(KRB_PROT_VERSION, p, 1); + p += krb_put_int(AUTH_MSG_SAFE, p, 1); + + start = p; + + p += krb_put_int(length, p, 4); + + memcpy(p, in, length); + p += length; + + gettimeofday(&tv, NULL); + + *p++ = tv.tv_usec/5000; /* 5ms */ + + src_addr = sender->sin_addr.s_addr; + p += krb_put_address(src_addr, p); + + p += krb_put_int(lsb_time(tv.tv_sec, sender, receiver), p, 4); + + { + /* We are faking big endian mode, so we need to fix the + * checksum (that is byte order dependent). We always send a + * checksum of the new type, unless we know that we are + * talking to an old client (this requires a call to + * krb_rd_safe first). + */ + unsigned char new_checksum[16]; + unsigned char old_checksum[16]; + fixup_quad_cksum(start, p - start, key, new_checksum, old_checksum, 0); + + if((dqc_type == DES_QUAD_GUESS && DES_QUAD_DEFAULT == DES_QUAD_OLD) || + dqc_type == DES_QUAD_OLD) + memcpy(p, old_checksum, 16); + else + memcpy(p, new_checksum, 16); + } + p += 16; + + return p - (unsigned char*)out; +} |