NetBSD/sys/ipkdb/ipkdb_ipkdb.c

1179 lines
30 KiB
C

/* $NetBSD: ipkdb_ipkdb.c,v 1.27 2009/10/02 22:05:52 elad Exp $ */
/*
* Copyright (C) 1993-2000 Wolfgang Solfrank.
* Copyright (C) 1993-2000 TooLs GmbH.
* 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 TooLs GmbH.
* 4. The name of TooLs GmbH may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``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 TOOLS GMBH 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 <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: ipkdb_ipkdb.c,v 1.27 2009/10/02 22:05:52 elad Exp $");
#include "opt_ipkdb.h"
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/mbuf.h>
#include <sys/reboot.h>
#include <sys/systm.h>
#include <sys/kauth.h>
#include <sys/cpu.h>
#include <net/if.h>
#include <net/if_arp.h>
#include <net/if_ether.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/if_inarp.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet/udp.h>
#include <machine/reg.h>
#include <ipkdb/ipkdb.h>
#include <machine/ipkdb.h>
int ipkdbpanic = 0;
#ifndef IPKDBKEY
#error You must specify the IPKDBKEY option to use IPKDB.
#else
static char ipkdbkey[] = IPKDBKEY;
#endif
static struct ipkdb_if ipkdb_if;
static kauth_listener_t ipkdb_listener;
static u_char *ipkdbaddr(u_char *, int *, void **);
static void peekmem(struct ipkdb_if *, u_char *, void *, long);
static void pokemem(struct ipkdb_if *, u_char *, void *, long);
static u_int32_t getnl(void *);
static u_int getns(void *);
static void setnl(void *, u_int32_t);
static void setns(void *, int);
static u_short cksum(u_short, void *, int);
static int assemble(struct ipkdb_if *, void *);
static char *inpkt(struct ipkdb_if *, char *, int);
static void outpkt(struct ipkdb_if *, char *, int, int, int);
static void init(struct ipkdb_if *);
static void *chksum(void *, int);
static void getpkt(struct ipkdb_if *, char *, int *);
static void putpkt(struct ipkdb_if *, const char *, int);
static int check_ipkdb(struct ipkdb_if *, struct in_addr *, char *, int);
static int connectipkdb(struct ipkdb_if *, char *, int);
static int hmac_init(void);
static int
ipkdb_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie,
void *arg0, void *arg1, void *arg2, void *arg3)
{
enum kauth_system_req req;
int result;
req = (enum kauth_system_req)arg0;
result = KAUTH_RESULT_DEFER;
if ((action != KAUTH_SYSTEM_DEBUG) ||
(req != KAUTH_REQ_SYSTEM_DEBUG_IPKDB))
return result;
result = KAUTH_RESULT_ALLOW;
return result;
}
void
ipkdb_init(void)
{
ipkdbinit();
if ( ipkdbifinit(&ipkdb_if) < 0
|| !(ipkdb_if.flags&IPKDB_MYHW)
|| !hmac_init()) {
/* Interface not found, drop IPKDB */
printf("IPKDB: No interface found!\n");
boothowto &= ~RB_KDB;
}
ipkdb_listener = kauth_listen_scope(KAUTH_SCOPE_SYSTEM,
ipkdb_listener_cb, NULL);
}
void
ipkdb_connect(int when)
{
boothowto |= RB_KDB;
if (when == 0)
printf("waiting for remote debugger\n");
ipkdb_trap();
}
void
ipkdb_panic(void)
{
ipkdbpanic = 1;
ipkdb_trap();
}
/*
* Doesn't handle overlapping regions!
*/
void
ipkdbcopy(const void *s, void *d, int n)
{
const char *sp = s;
char *dp = d;
while (--n >= 0)
*dp++ = *sp++;
}
void
ipkdbzero(void *d, int n)
{
char *dp = d;
while (--n >= 0)
*dp++ = 0;
}
int
ipkdbcmp(void *s, void *d, int n)
{
char *sp = s, *dp = d;
while (--n >= 0)
if (*sp++ != *dp++)
return *--dp - *--sp;
return 0;
}
int
ipkdbcmds(void)
{
static char buf[512];
char *cp;
int plen;
if (!(ipkdb_if.flags&IPKDB_MYHW)) /* no interface */
return IPKDB_CMD_EXIT;
init(&ipkdb_if);
if (ipkdbpanic > 1) {
ipkdb_if.leave(&ipkdb_if);
return IPKDB_CMD_RUN;
}
putpkt(&ipkdb_if, "s", 1);
while (1) {
getpkt(&ipkdb_if, buf, &plen);
if (!plen) {
if (ipkdbpanic && ipkdb_poll()) {
ipkdb_if.leave(&ipkdb_if);
return IPKDB_CMD_RUN;
} else
continue;
} else
ipkdbpanic = 0;
switch (*buf) {
default:
putpkt(&ipkdb_if, "eunknown command", 16);
break;
case 'O':
/* This is an allowed reconnect, ack it */
putpkt(&ipkdb_if, "s", 1);
break;
case 'R':
peekmem(&ipkdb_if, buf, ipkdbregs, sizeof ipkdbregs);
break;
case 'W':
if (plen != sizeof ipkdbregs + 1) {
putpkt(&ipkdb_if, "einvalid register size", 22);
break;
}
pokemem(&ipkdb_if, buf + 1, ipkdbregs, sizeof ipkdbregs);
break;
case 'M':
{
void *addr, *len;
plen--;
if ( !(cp = ipkdbaddr(buf + 1, &plen, &addr))
|| !ipkdbaddr(cp, &plen, &len)) {
putpkt(&ipkdb_if, "einvalid peek format", 20);
break;
}
peekmem(&ipkdb_if, buf, addr, (long)len);
break;
}
case 'N':
{
void *addr, *len;
plen--;
if ( !(cp = ipkdbaddr(buf + 1, &plen, &addr))
|| !(cp = ipkdbaddr(cp, &plen, &len))
|| plen < (long)len) {
putpkt(&ipkdb_if, "einvalid poke format", 20);
break;
}
pokemem(&ipkdb_if, cp, addr, (long)len);
break;
}
case 'S':
ipkdb_if.leave(&ipkdb_if);
return IPKDB_CMD_STEP;
case 'X':
putpkt(&ipkdb_if, "ok",2);
ipkdb_if.leave(&ipkdb_if);
return IPKDB_CMD_EXIT;
case 'C':
ipkdb_if.leave(&ipkdb_if);
return IPKDB_CMD_RUN;
}
}
}
static u_char *
ipkdbaddr(u_char *cp, int *pl, void **dp)
{
/* Assume that sizeof(void *) <= sizeof(u_long) */
u_long l;
int i;
if ((*pl -= sizeof *dp) < 0)
return 0;
for (i = sizeof *dp, l = 0; --i >= 0;) {
l <<= 8;
l |= *cp++;
}
*dp = (void *)l;
return cp;
}
static void
peekmem(struct ipkdb_if *ifp, u_char *buf, void *addr, long len)
{
u_char *cp, *p = addr;
int l;
cp = buf;
*cp++ = 'p';
for (l = len; --l >= 0;)
*cp++ = ipkdbfbyte(p++);
putpkt(ifp, buf, len + 1);
}
static void
pokemem(struct ipkdb_if *ifp, u_char *cp, void *addr, long len)
{
u_char *p = addr;
while (--len >= 0)
ipkdbsbyte(p++, *cp++);
putpkt(ifp, "ok", 2);
}
inline static u_int32_t
getnl(void *vs)
{
u_char *s = vs;
return (*s << 24)|(s[1] << 16)|(s[2] << 8)|s[3];
}
inline static u_int
getns(void *vs)
{
u_char *s = vs;
return (*s << 8)|s[1];
}
inline static void
setnl(void *vs, u_int32_t l)
{
u_char *s = vs;
*s++ = l >> 24;
*s++ = l >> 16;
*s++ = l >> 8;
*s = l;
}
inline static void
setns(void *vs, int l)
{
u_char *s = vs;
*s++ = l >> 8;
*s = l;
}
static u_short
cksum(u_short st, void *vcp, int l)
{
u_char *cp = vcp;
u_long s;
for (s = st; (l -= 2) >= 0; cp += 2)
s += (*cp << 8) + cp[1];
if (l == -1)
s += *cp << 8;
while (s&0xffff0000)
s = (s&0xffff) + (s >> 16);
return s == 0xffff ? 0 : s;
}
static int
assemble(struct ipkdb_if *ifp, void *buf)
{
struct ip *ip, iph;
int off, len, i;
u_char *cp, *ecp;
ip = (struct ip *)buf;
ipkdbcopy(ip, &iph, sizeof iph);
iph.ip_hl = 5;
iph.ip_tos = 0;
iph.ip_len = 0;
iph.ip_off = 0;
iph.ip_ttl = 0;
iph.ip_sum = 0;
if (ifp->asslen) {
if (ipkdbcmp(&iph, ifp->ass, sizeof iph)) {
/*
* different packet
* decide whether to keep the old
* or start a new one
*/
i = (getns(&ip->ip_id)
^ getns(&((struct ip *)ifp->ass)->ip_id));
i ^= ((i >> 2) ^ (i >> 4) ^ (i >> 8) ^ (i >> 12));
if (i & 1)
/* keep the old */
return 0;
ifp->asslen = 0;
}
}
if (!ifp->asslen) {
ipkdbzero(ifp->assbit, sizeof ifp->assbit);
ipkdbcopy(&iph, ifp->ass, sizeof iph);
}
off = getns(&ip->ip_off);
len = ((off & IP_OFFMASK) << 3) + getns(&ip->ip_len) - ip->ip_hl * 4;
if (ifp->asslen < len)
ifp->asslen = len;
if (ifp->asslen + sizeof *ip > sizeof ifp->ass) {
/* packet too long */
ifp->asslen = 0;
return 0;
}
if (!(off & IP_MF)) {
off &= IP_OFFMASK;
cp = ifp->assbit + (off >> 3);
for (i = (off & 7); i < 8; *cp |= 1 << i++);
for (; cp < ifp->assbit + sizeof ifp->assbit; *cp++ = -1);
} else {
off &= IP_OFFMASK;
cp = ifp->assbit + (off >> 3);
ecp = ifp->assbit + (len >> 6);
if (cp == ecp)
for (i = (off & 7); i <= ((len >> 3) & 7);
*cp |= 1 << i++);
else {
for (i = (off & 7); i < 8; *cp |= 1 << i++);
for (; ++cp < ecp; *cp = -1);
for (i = 0; i < ((len >> 3) & 7); *cp |= 1 << i++);
}
}
ipkdbcopy((char *)buf + ip->ip_hl * 4,
ifp->ass + sizeof *ip + (off << 3),
len - (off << 3));
for (cp = ifp->assbit; cp < ifp->assbit + sizeof ifp->assbit;)
if (*cp++ != (u_char)-1)
/* not complete */
return 0;
ip = (struct ip *)ifp->ass;
setns(&ip->ip_len, sizeof *ip + ifp->asslen);
/* complete */
return 1;
}
static char *
inpkt(struct ipkdb_if *ifp, char *ibuf, int poll)
{
int cnt = 1000000;
int l, ul;
struct ether_header *eh;
struct arphdr *ah;
struct ip *ip;
struct udphdr *udp;
struct ipovly ipo;
while (1) {
l = ifp->receive(ifp, ibuf, poll != 0);
if (!l) {
if (poll == 1 || (poll == 2 && --cnt <= 0))
break;
else
continue;
}
eh = (struct ether_header *)ibuf;
switch (getns(&eh->ether_type)) {
case ETHERTYPE_ARP:
ah = (struct arphdr *)(ibuf + 14);
if ( getns(&ah->ar_hrd) != ARPHRD_ETHER
|| getns(&ah->ar_pro) != ETHERTYPE_IP
|| ah->ar_hln != 6
|| ah->ar_pln != 4)
/* unsupported arp packet */
break;
switch (getns(&ah->ar_op)) {
case ARPOP_REQUEST:
if ( (ifp->flags&IPKDB_MYIP)
&& !ipkdbcmp(ar_tpa(ah),
ifp->myinetaddr,
sizeof ifp->myinetaddr)) {
/* someone requested my address */
ipkdbcopy(eh->ether_shost,
eh->ether_dhost,
sizeof eh->ether_dhost);
ipkdbcopy(ifp->myenetaddr,
eh->ether_shost,
sizeof eh->ether_shost);
setns(&ah->ar_op, ARPOP_REPLY);
ipkdbcopy(ar_sha(ah),
ar_tha(ah),
ah->ar_hln);
ipkdbcopy(ar_spa(ah),
ar_tpa(ah),
ah->ar_pln);
ipkdbcopy(ifp->myenetaddr,
ar_sha(ah),
ah->ar_hln);
ipkdbcopy(ifp->myinetaddr,
ar_spa(ah),
ah->ar_pln);
ifp->send(ifp, ibuf, 74);
continue;
}
break;
default:
break;
}
break;
case ETHERTYPE_IP:
ip = (struct ip *)(ibuf + 14);
if ( ip->ip_v != IPVERSION
|| ip->ip_hl < 5
|| getns(&ip->ip_len) + 14 > l)
/* invalid packet */
break;
if (cksum(0, ip, ip->ip_hl * 4))
/* wrong checksum */
break;
if (ip->ip_p != IPPROTO_UDP)
break;
if (getns(&ip->ip_off) & ~IP_DF) {
if (!assemble(ifp, ip))
break;
ip = (struct ip *)ifp->ass;
ifp->asslen = 0;
}
udp = (struct udphdr *)((char *)ip + ip->ip_hl * 4);
ul = getns(&ip->ip_len) - ip->ip_hl * 4;
if (getns(&udp->uh_ulen) != ul)
/* invalid UDP packet length */
break;
ipkdbcopy(ip, &ipo, sizeof ipo);
ipkdbzero(ipo.ih_x1, sizeof ipo.ih_x1);
ipo.ih_len = udp->uh_ulen;
if ( udp->uh_sum
&& cksum(cksum(0, &ipo, sizeof ipo), udp, ul))
/* wrong checksum */
break;
if (!(ifp->flags & IPKDB_MYIP)) {
if ( getns(&udp->uh_sport) == 67
&& getns(&udp->uh_dport) == 68
&& *(char *)(udp + 1) == 2) {
/* this is a BOOTP reply to our ethernet address */
/* should check a bit more? XXX */
char *bootp = (char *)(udp + 1);
ipkdbcopy(bootp + 16,
ifp->myinetaddr,
sizeof ifp->myinetaddr);
ifp->flags |= IPKDB_MYIP;
}
/* give caller a chance to resend his request */
return 0;
}
if ( ipkdbcmp(&ip->ip_dst, ifp->myinetaddr, sizeof ifp->myinetaddr)
|| getns(&udp->uh_dport) != IPKDBPORT)
break;
/* so now it's a UDP packet for the debugger */
{
/* Check for reconnect packet */
u_char *p;
p = (u_char *)(udp + 1);
if (!getnl(p) && p[6] == 'O') {
l = getns(p + 4);
if ( l <= ul - sizeof *udp - 6
&& check_ipkdb(ifp, &ip->ip_src,
p, l + 6)) {
ipkdbcopy(&ip->ip_src,
ifp->hisinetaddr,
sizeof ifp->hisinetaddr);
ipkdbcopy(eh->ether_shost,
ifp->hisenetaddr,
sizeof ifp->hisenetaddr);
ifp->hisport = getns(&udp->uh_sport);
ifp->flags |= IPKDB_HISHW|IPKDB_HISIP;
return p;
}
}
}
if ( (ifp->flags&IPKDB_HISIP)
&& ipkdbcmp(&ip->ip_src,
ifp->hisinetaddr, sizeof ifp->hisinetaddr))
/* It's a packet from someone else */
break;
if (!(ifp->flags&IPKDB_HISIP))
break;
return (char *)(udp + 1);
default:
/* unknown type */
break;
}
}
return 0;
}
static short ipkdb_ipid = 0;
static void
outpkt(struct ipkdb_if *ifp, char *in, int l, int srcport, int dstport)
{
struct ether_header *eh;
struct ip *ip;
struct udphdr *udp;
u_char *cp;
char _obuf[ETHERMTU + 16];
#define obuf (_obuf + 2) /* align ip data in packet */
struct ipovly ipo;
int i, off;
ipkdbzero(_obuf, sizeof _obuf);
eh = (struct ether_header *)obuf;
/*
* If we don't have his ethernet address, or this is a bootp request,
* broadcast the packet.
*/
if (!(ifp->flags & IPKDB_HISHW)
|| dstport == 67)
for (cp = eh->ether_dhost;
cp < eh->ether_dhost + sizeof eh->ether_dhost;
*cp++ = -1);
else
ipkdbcopy(ifp->hisenetaddr, eh->ether_dhost, sizeof eh->ether_dhost);
ipkdbcopy(ifp->myenetaddr, eh->ether_shost, sizeof eh->ether_shost);
setns(&eh->ether_type, ETHERTYPE_IP);
ip = (struct ip *)(obuf + 14);
ip->ip_v = IPVERSION;
ip->ip_hl = 5;
setns(&ip->ip_id, ipkdb_ipid++);
ip->ip_ttl = 255;
ip->ip_p = IPPROTO_UDP;
ipkdbcopy(ifp->myinetaddr, &ip->ip_src, sizeof ip->ip_src);
/*
* If this is a bootp request, broadcast it.
*/
if (dstport == 67)
for (cp = (u_char *)&ip->ip_dst;
cp < (u_char *)&ip->ip_dst + sizeof ip->ip_dst;
*cp++ = -1);
else
ipkdbcopy(ifp->hisinetaddr, &ip->ip_dst, sizeof ip->ip_dst);
udp = (struct udphdr *)(ip + 1);
setns(&udp->uh_sport, srcport);
setns(&udp->uh_dport, dstport);
setns(&udp->uh_ulen, l + sizeof *udp);
ipkdbcopy(ip, &ipo, sizeof ipo);
ipkdbzero(ipo.ih_x1, sizeof ipo.ih_x1);
ipo.ih_len = udp->uh_ulen;
setns(&udp->uh_sum,
~cksum(cksum(cksum(0, &ipo, sizeof ipo),
udp, sizeof *udp),
in, l));
for (cp = (u_char *)(udp + 1), l += sizeof *udp, off = 0;
l > 0;
l -= i, in += i, off += i, cp = (u_char *)udp) {
i = l > ifp->mtu - sizeof *ip ? ((ifp->mtu - sizeof *ip) & ~7) : l;
ipkdbcopy(in, cp, i);
setns(&ip->ip_len, i + sizeof *ip);
setns(&ip->ip_off, (l > i ? IP_MF : 0) | (off >> 3));
ip->ip_sum = 0;
setns(&ip->ip_sum, ~cksum(0, ip, sizeof *ip));
if (i + sizeof *ip < ETHERMIN)
i = ETHERMIN - sizeof *ip;
ifp->send(ifp, obuf, i + sizeof *ip + 14);
}
#undef obuf
}
static void
init(struct ipkdb_if *ifp)
{
u_char *cp;
u_char _ibuf[ETHERMTU + 16];
#define ibuf (_ibuf + 2) /* align ip data in packet */
int secs = 0;
ifp->start(ifp);
if (ifp->flags & IPKDB_MYIP)
return;
while (!(ifp->flags & IPKDB_MYIP)) {
ipkdbzero(_ibuf, sizeof _ibuf);
cp = _ibuf;
*cp++ = 1; /* BOOTP_REQUEST */
*cp++ = 1; /* Ethernet hardware */
*cp++ = 6; /* length of address */
setnl(++cp, 0x12345678); /* some random number? */
setns(cp + 4, secs++);
ipkdbcopy(ifp->myenetaddr, cp + 24, sizeof ifp->myenetaddr);
outpkt(ifp, _ibuf, 300, 68, 67);
inpkt(ifp, ibuf, 2);
if (ipkdbpanic && ipkdb_poll()) {
ipkdbpanic++;
return;
}
}
cp = ifp->myinetaddr;
printf("My IP address is %d.%d.%d.%d\n",
cp[0], cp[1], cp[2], cp[3]);
#undef ibuf
}
/* HMAC Checksumming routines, see draft-ietf-ipsec-hmac-md5-00.txt */
#define LENCHK 16 /* Length of checksum in bytes */
/*
* This code is based on the MD5 implementation as found in ssh.
* It's quite a bit hacked by myself, but the original has
* the following non-copyright comments on it:
*/
/* This code has been heavily hacked by Tatu Ylonen <ylo@cs.hut.fi> to
make it compile on machines like Cray that don't have a 32 bit integer
type. */
/*
* This code implements the MD5 message-digest algorithm.
* The algorithm is due to Ron Rivest. This code was
* written by Colin Plumb in 1993, no copyright is claimed.
* This code is in the public domain; do with it what you wish.
*
* Equivalent code is available from RSA Data Security, Inc.
* This code has been tested against that, and is equivalent,
* except that you don't need to include two pages of legalese
* with every copy.
*/
static struct ipkdb_MD5Context {
u_int buf[4];
u_int bits[2];
u_char in[64];
} icontext, ocontext;
static u_int32_t getNl(void *);
static void setNl(void *, u_int32_t);
static void ipkdb_MD5Transform(struct ipkdb_MD5Context *);
static void ipkdb_MD5Init(struct ipkdb_MD5Context *);
static void ipkdb_MD5Update(struct ipkdb_MD5Context *, u_char *, u_int);
static u_char *ipkdb_MD5Final(struct ipkdb_MD5Context *);
inline static u_int32_t
getNl(void *vs)
{
u_char *s = vs;
return *s | (s[1] << 8) | (s[2] << 16) | (s[3] << 24);
}
inline static void
setNl(void *vs, u_int32_t l)
{
u_char *s = vs;
*s++ = l;
*s++ = l >> 8;
*s++ = l >> 16;
*s = l >> 24;
}
/* The four core functions - F1 is optimized somewhat */
/* #define F1(x, y, z) (((x) & (y)) | (~(x) & (z))) */
#define F1(x, y, z) ((z) ^ ((x) & ((y) ^ (z))))
#define F2(x, y, z) F1(z, x, y)
#define F3(x, y, z) ((x) ^ (y) ^ (z))
#define F4(x, y, z) ((y) ^ ((x) | ~(z)))
/* This is the central step in the MD5 algorithm. */
#define ipkdb_MD5STEP(f, w, x, y, z, data, s) \
((w) += f(x, y, z) + (data), \
(w) = ((w) << (s)) | (((w) >> (32 - s)) & 0xffffffff), \
(w) += (x))
/*
* The core of the MD5 algorithm, this alters an existing MD5 hash to
* reflect the addition of 16 longwords of new data. MD5Update blocks
* the data for this routine.
*/
static void
ipkdb_MD5Transform(struct ipkdb_MD5Context *ctx)
{
u_int a, b, c, d, i;
u_int in[16];
for (i = 0; i < 16; i++)
in[i] = getNl(ctx->in + 4 * i);
a = ctx->buf[0];
b = ctx->buf[1];
c = ctx->buf[2];
d = ctx->buf[3];
ipkdb_MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
ipkdb_MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
ipkdb_MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
ipkdb_MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
ipkdb_MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
ipkdb_MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
ipkdb_MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
ipkdb_MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
ipkdb_MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
ipkdb_MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
ipkdb_MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
ipkdb_MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
ipkdb_MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
ipkdb_MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
ipkdb_MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
ipkdb_MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
ipkdb_MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
ipkdb_MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
ipkdb_MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
ipkdb_MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
ipkdb_MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
ipkdb_MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
ipkdb_MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
ipkdb_MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
ipkdb_MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
ipkdb_MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
ipkdb_MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
ipkdb_MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
ipkdb_MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
ipkdb_MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
ipkdb_MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
ipkdb_MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
ipkdb_MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
ipkdb_MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
ipkdb_MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
ipkdb_MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
ipkdb_MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
ipkdb_MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
ipkdb_MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
ipkdb_MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
ipkdb_MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
ipkdb_MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
ipkdb_MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
ipkdb_MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
ipkdb_MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
ipkdb_MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
ipkdb_MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
ipkdb_MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
ipkdb_MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
ipkdb_MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
ipkdb_MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
ipkdb_MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
ipkdb_MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
ipkdb_MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
ipkdb_MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
ipkdb_MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
ipkdb_MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
ipkdb_MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
ipkdb_MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
ipkdb_MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
ipkdb_MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
ipkdb_MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
ipkdb_MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
ipkdb_MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
ctx->buf[0] += a;
ctx->buf[1] += b;
ctx->buf[2] += c;
ctx->buf[3] += d;
}
/*
* Start MD5 accumulation. Set bit count to 0 and buffer to mysterious
* initialization constants.
*/
static void
ipkdb_MD5Init(struct ipkdb_MD5Context *ctx)
{
ctx->buf[0] = 0x67452301;
ctx->buf[1] = 0xefcdab89;
ctx->buf[2] = 0x98badcfe;
ctx->buf[3] = 0x10325476;
ctx->bits[0] = 0;
ctx->bits[1] = 0;
}
/*
* Update context to reflect the concatenation of another buffer full
* of bytes.
*/
static void
ipkdb_MD5Update(struct ipkdb_MD5Context *ctx, u_char *buf, unsigned len)
{
u_int t;
/* Update bitcount */
t = ctx->bits[0];
if ((ctx->bits[0] = (t + (len << 3)) & 0xffffffff) < t)
ctx->bits[1]++; /* Carry from low to high */
ctx->bits[1] += (len >> 29) & 0xffffffff;
t = (t >> 3) & 0x3f; /* Bytes already in ctx->in */
/* Handle any leading odd-sized chunks */
if (t) {
u_char *p = ctx->in + t;
t = 64 - t;
if (len < t) {
ipkdbcopy(buf, p, len);
return;
}
ipkdbcopy(buf, p, t);
ipkdb_MD5Transform(ctx);
buf += t;
len -= t;
}
/* Process data in 64-byte chunks */
while (len >= 64) {
ipkdbcopy(buf, ctx->in, 64);
ipkdb_MD5Transform(ctx);
buf += 64;
len -= 64;
}
/* Handle any remaining bytes of data. */
ipkdbcopy(buf, ctx->in, len);
}
/*
* Final wrapup - pad to 64-byte boundary with the bit pattern
* 1 0* (64-bit count of bits processed, LSB-first)
*/
static u_char *
ipkdb_MD5Final(struct ipkdb_MD5Context *ctx)
{
static u_char digest[16];
unsigned count;
u_char *p;
/* Compute number of bytes mod 64 */
count = (ctx->bits[0] >> 3) & 0x3f;
/* Set the first char of padding to 0x80. This is safe since there is
always at least one byte free */
p = ctx->in + count;
*p++ = 0x80;
/* Bytes of padding needed to make 64 bytes */
count = 64 - 1 - count;
/* Pad out to 56 mod 64 */
if (count < 8) {
/* Two lots of padding: Pad the first block to 64 bytes */
ipkdbzero(p, count);
ipkdb_MD5Transform(ctx);
/* Now fill the next block with 56 bytes */
ipkdbzero(ctx->in, 56);
} else
/* Pad block to 56 bytes */
ipkdbzero(p, count - 8);
/* Append length in bits and transform */
setNl(ctx->in + 56, ctx->bits[0]);
setNl(ctx->in + 60, ctx->bits[1]);
ipkdb_MD5Transform(ctx);
setNl(digest, ctx->buf[0]);
setNl(digest + 4, ctx->buf[1]);
setNl(digest + 8, ctx->buf[2]);
setNl(digest + 12, ctx->buf[3]);
return digest;
}
/*
* The following code is more or less stolen from the hmac_md5
* function in the Appendix of the HMAC IETF draft, but is
* optimized as suggested in this same paper.
*/
static int
hmac_init(void)
{
char pad[64];
char tk[16];
u_char *key = ipkdbkey;
int key_len = strlen(key);
int i;
/* Require key to be at least 16 bytes long */
if (key_len < 16) {
printf("IPKDBKEY must be at least 16 bytes long!\n");
ipkdbzero(key, key_len); /* XXX */
return 0;
}
/* if key is longer than 64 bytes reset it to key=MD5(key) */
if (key_len > 64) {
ipkdb_MD5Init(&icontext);
ipkdb_MD5Update(&icontext, key, key_len);
ipkdbcopy(ipkdb_MD5Final(&icontext), tk, 16);
ipkdbzero(key, key_len); /* XXX */
key = tk;
key_len = 16;
}
/*
* the HMAC_MD5 transform looks like:
*
* MD5(K XOR opad, MD5(K XOR ipad, text))
*
* where K is and n byte key
* ipad is the byte 0x36 repeated 64 times
* opad is the byte 0x5c repeated 64 times
* and text is the data being protected
*/
/*
* We do the initial part of MD5(K XOR ipad)
* and MD5(K XOR opad) here, in order to
* speed up the computation later on.
*/
ipkdbzero(pad, sizeof pad);
ipkdbcopy(key, pad, key_len);
for (i = 0; i < 64; i++)
pad[i] ^= 0x36;
ipkdb_MD5Init(&icontext);
ipkdb_MD5Update(&icontext, pad, 64);
ipkdbzero(pad, sizeof pad);
ipkdbcopy(key, pad, key_len);
for (i = 0; i < 64; i++)
pad[i] ^= 0x5c;
ipkdb_MD5Init(&ocontext);
ipkdb_MD5Update(&ocontext, pad, 64);
/* Zero out the key XXX */
ipkdbzero(key, key_len);
return 1;
}
/*
* This is more or less hmac_md5 from the HMAC IETF draft, Appendix.
*/
static void *
chksum(void *buf, int len)
{
u_char *digest;
struct ipkdb_MD5Context context;
/*
* the HMAC_MD5 transform looks like:
*
* MD5(K XOR opad, MD5(K XOR ipad, text))
*
* where K is an n byte key
* ipad is the byte 0x36 repeated 64 times
* opad is the byte 0x5c repeated 64 times
* and text is the data being protected
*/
/*
* Since we've already done the precomputation,
* we can now stuff the data into the relevant
* preinitialized contexts to get the result.
*/
/*
* perform inner MD5
*/
ipkdbcopy(&icontext, &context, sizeof context);
ipkdb_MD5Update(&context, buf, len);
digest = ipkdb_MD5Final(&context);
/*
* perform outer MD5
*/
ipkdbcopy(&ocontext, &context, sizeof context);
ipkdb_MD5Update(&context, digest, 16);
return ipkdb_MD5Final(&context);
}
static void
getpkt(struct ipkdb_if *ifp, char *buf, int *lp)
{
char *got;
int l;
char _ibuf[ETHERMTU + 16];
#define ibuf (_ibuf + 2) /* align ip data in packet */
*lp = 0;
while (1) {
if (!(got = inpkt(ifp, ibuf, ipkdbpanic != 0))) {
*lp = 0;
return;
}
if ( ifp->seq == getnl(got)
&& got[6] >= 'A'
&& got[6] <= 'Z'
&& (l = getns(got + 4))
&& !ipkdbcmp(chksum(got, l + 6), got + l + 6, LENCHK)) {
ipkdbcopy(got + 6, buf, *lp = l);
return;
}
if ( ifp->pktlen
&& ((ifp->flags & (IPKDB_MYIP | IPKDB_HISIP | IPKDB_CONNECTED))
== (IPKDB_MYIP | IPKDB_HISIP | IPKDB_CONNECTED)))
outpkt(ifp, ifp->pkt, ifp->pktlen, IPKDBPORT, ifp->hisport);
}
#undef ibuf
}
static void
putpkt(struct ipkdb_if *ifp, const char *buf, int l)
{
setnl(ifp->pkt, ifp->seq++);
setns(ifp->pkt + 4, l);
ipkdbcopy(buf, ifp->pkt + 6, l);
ipkdbcopy(chksum(ifp->pkt, l + 6), ifp->pkt + 6 + l, LENCHK);
ifp->pktlen = l + 6 + LENCHK;
if ( (ifp->flags & (IPKDB_MYIP | IPKDB_HISIP | IPKDB_CONNECTED))
!= (IPKDB_MYIP | IPKDB_HISIP | IPKDB_CONNECTED))
return;
outpkt(ifp, ifp->pkt, ifp->pktlen, IPKDBPORT, ifp->hisport);
}
static int
check_ipkdb(struct ipkdb_if *ifp, struct in_addr *shost, char *p, int l)
{
u_char hisenet[6];
u_char hisinet[4];
u_int16_t hisport;
char save;
#ifndef IPKDBSECURE
if (kauth_authorize_system(curlwp->l_cred, KAUTH_SYSTEM_DEBUG,
KAUTH_REQ_SYSTEM_DEBUG_IPKDB, NULL, NULL, NULL))
return 0;
#endif
if (ipkdbcmp(chksum(p, l), p + l, LENCHK))
return 0;
ipkdbcopy(ifp->hisenetaddr, hisenet, sizeof hisenet);
ipkdbcopy(ifp->hisinetaddr, hisinet, sizeof hisinet);
hisport = ifp->hisport;
save = ifp->flags;
ipkdbcopy(shost, ifp->hisinetaddr, sizeof ifp->hisinetaddr);
ifp->flags &= ~IPKDB_HISHW;
ifp->flags |= IPKDB_HISIP;
if (connectipkdb(ifp, p + 6, l - 6) < 0) {
ipkdbcopy(hisenet, ifp->hisenetaddr, sizeof ifp->hisenetaddr);
ipkdbcopy(hisinet, ifp->hisinetaddr, sizeof ifp->hisinetaddr);
ifp->hisport = hisport;
ifp->flags = save;
return 0;
}
return 1;
}
/*
* Should check whether packet came across the correct interface. XXX
*/
int
checkipkdb(struct in_addr *shost, u_short sport, u_short dport, struct mbuf *m, int off, int len)
{
char *p;
int l;
char ibuf[ETHERMTU+50];
if (dport != IPKDBPORT)
return 0;
if (len > sizeof ibuf)
return 0;
m_copydata(m, off, len, ibuf);
p = ibuf;
if (getnl(p) || p[6] != 'O')
return 0;
l = getns(p + 4);
if (l > len - 6 || !check_ipkdb(&ipkdb_if, shost, p, l + 6))
return 0;
ipkdb_if.hisport = sport;
ipkdb_connect(1);
return 1;
}
static int
connectipkdb(struct ipkdb_if *ifp, char *buf, int l)
{
char *cp;
u_char *ip;
if (*buf != 'O')
return -1;
if (getnl(buf + 1) == ifp->id)
/* It's a retry of a connect packet, ignore it */
return -1;
ip = ifp->hisinetaddr;
printf("debugged by ");
l -= 1 + sizeof(u_int32_t);
for (cp = buf + 1 + sizeof(u_int32_t); --l >= 0; printf("%c", *cp++));
printf(" (%d.%d.%d.%d)\n", ip[0], ip[1], ip[2], ip[3]);
ifp->flags |= IPKDB_CONNECTED;
ifp->seq = 0;
ifp->pktlen = 0;
ifp->id = getnl(buf + 1);
return 0;
}