freebsd-src/lib/libstand/net.c
Mike Smith 6b4f575cb1 This is libstand; a support library for standalone executables (eg. bootstrap
modules).
Obtained from: NetBSD, with some architectural changes and many additions.
1998-08-20 08:19:55 +00:00

504 lines
11 KiB
C

/* $NetBSD: net.c,v 1.20 1997/12/26 22:41:30 scottr Exp $ */
/*
* Copyright (c) 1992 Regents of the University of California.
* All rights reserved.
*
* This software was developed by the Computer Systems Engineering group
* at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
* contributed to Berkeley.
*
* 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 University of
* California, Lawrence Berkeley Laboratory and its contributors.
* 4. Neither the name of the University 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 REGENTS 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 REGENTS 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.
*
* @(#) Header: net.c,v 1.9 93/08/06 19:32:15 leres Exp (LBL)
*/
#include <sys/param.h>
#include <sys/socket.h>
#include <string.h>
#include <net/if.h>
#include <netinet/in.h>
#include <netinet/if_ether.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet/udp.h>
#include <netinet/udp_var.h>
#include "stand.h"
#include "net.h"
/* Caller must leave room for ethernet, ip and udp headers in front!! */
ssize_t
sendudp(d, pkt, len)
register struct iodesc *d;
register void *pkt;
register size_t len;
{
register ssize_t cc;
register struct ip *ip;
register struct udphdr *uh;
register u_char *ea;
#ifdef NET_DEBUG
if (debug) {
printf("sendudp: d=%lx called.\n", (long)d);
if (d) {
printf("saddr: %s:%d",
inet_ntoa(d->myip), ntohs(d->myport));
printf(" daddr: %s:%d\n",
inet_ntoa(d->destip), ntohs(d->destport));
}
}
#endif
uh = (struct udphdr *)pkt - 1;
ip = (struct ip *)uh - 1;
len += sizeof(*ip) + sizeof(*uh);
bzero(ip, sizeof(*ip) + sizeof(*uh));
ip->ip_v = IPVERSION; /* half-char */
ip->ip_hl = sizeof(*ip) >> 2; /* half-char */
ip->ip_len = htons(len);
ip->ip_p = IPPROTO_UDP; /* char */
ip->ip_ttl = IP_TTL; /* char */
ip->ip_src = d->myip;
ip->ip_dst = d->destip;
ip->ip_sum = in_cksum(ip, sizeof(*ip)); /* short, but special */
uh->uh_sport = d->myport;
uh->uh_dport = d->destport;
uh->uh_ulen = htons(len - sizeof(*ip));
#ifndef UDP_NO_CKSUM
{
register struct udpiphdr *ui;
struct ip tip;
/* Calculate checksum (must save and restore ip header) */
tip = *ip;
ui = (struct udpiphdr *)ip;
bzero(&ui->ui_x1, sizeof(ui->ui_x1));
ui->ui_len = uh->uh_ulen;
uh->uh_sum = in_cksum(ui, len);
*ip = tip;
}
#endif
if (ip->ip_dst.s_addr == INADDR_BROADCAST || ip->ip_src.s_addr == 0 ||
netmask == 0 || SAMENET(ip->ip_src, ip->ip_dst, netmask))
ea = arpwhohas(d, ip->ip_dst);
else
ea = arpwhohas(d, gateip);
cc = sendether(d, ip, len, ea, ETHERTYPE_IP);
if (cc == -1)
return (-1);
if (cc != len)
panic("sendudp: bad write (%d != %d)", cc, len);
return (cc - (sizeof(*ip) + sizeof(*uh)));
}
/*
* Receive a UDP packet and validate it is for us.
* Caller leaves room for the headers (Ether, IP, UDP)
*/
ssize_t
readudp(d, pkt, len, tleft)
register struct iodesc *d;
register void *pkt;
register size_t len;
time_t tleft;
{
register ssize_t n;
register size_t hlen;
register struct ip *ip;
register struct udphdr *uh;
u_int16_t etype; /* host order */
#ifdef NET_DEBUG
if (debug)
printf("readudp: called\n");
#endif
uh = (struct udphdr *)pkt - 1;
ip = (struct ip *)uh - 1;
n = readether(d, ip, len + sizeof(*ip) + sizeof(*uh), tleft, &etype);
if (n == -1 || n < sizeof(*ip) + sizeof(*uh))
return -1;
/* Ethernet address checks now in readether() */
/* Need to respond to ARP requests. */
if (etype == ETHERTYPE_ARP) {
struct arphdr *ah = (void *)ip;
if (ah->ar_op == htons(ARPOP_REQUEST)) {
/* Send ARP reply */
arp_reply(d, ah);
}
return -1;
}
if (etype != ETHERTYPE_IP) {
#ifdef NET_DEBUG
if (debug)
printf("readudp: not IP. ether_type=%x\n", etype);
#endif
return -1;
}
/* Check ip header */
if (ip->ip_v != IPVERSION ||
ip->ip_p != IPPROTO_UDP) { /* half char */
#ifdef NET_DEBUG
if (debug)
printf("readudp: IP version or not UDP. ip_v=%d ip_p=%d\n", ip->ip_v, ip->ip_p);
#endif
return -1;
}
hlen = ip->ip_hl << 2;
if (hlen < sizeof(*ip) ||
in_cksum(ip, hlen) != 0) {
#ifdef NET_DEBUG
if (debug)
printf("readudp: short hdr or bad cksum.\n");
#endif
return -1;
}
if (n < ntohs(ip->ip_len)) {
#ifdef NET_DEBUG
if (debug)
printf("readudp: bad length %d < %d.\n",
(int)n, ntohs(ip->ip_len));
#endif
return -1;
}
if (d->myip.s_addr && ip->ip_dst.s_addr != d->myip.s_addr) {
#ifdef NET_DEBUG
if (debug) {
printf("readudp: bad saddr %s != ", inet_ntoa(d->myip));
printf("%s\n", inet_ntoa(ip->ip_dst));
}
#endif
return -1;
}
/* If there were ip options, make them go away */
if (hlen != sizeof(*ip)) {
bcopy(((u_char *)ip) + hlen, uh, len - hlen);
ip->ip_len = htons(sizeof(*ip));
n -= hlen - sizeof(*ip);
}
if (uh->uh_dport != d->myport) {
#ifdef NET_DEBUG
if (debug)
printf("readudp: bad dport %d != %d\n",
d->myport, ntohs(uh->uh_dport));
#endif
return -1;
}
#ifndef UDP_NO_CKSUM
if (uh->uh_sum) {
register struct udpiphdr *ui;
struct ip tip;
n = ntohs(uh->uh_ulen) + sizeof(*ip);
if (n > RECV_SIZE - ETHER_SIZE) {
printf("readudp: huge packet, udp len %d\n", (int)n);
return -1;
}
/* Check checksum (must save and restore ip header) */
tip = *ip;
ui = (struct udpiphdr *)ip;
bzero(&ui->ui_x1, sizeof(ui->ui_x1));
ui->ui_len = uh->uh_ulen;
if (in_cksum(ui, n) != 0) {
#ifdef NET_DEBUG
if (debug)
printf("readudp: bad cksum\n");
#endif
*ip = tip;
return -1;
}
*ip = tip;
}
#endif
if (ntohs(uh->uh_ulen) < sizeof(*uh)) {
#ifdef NET_DEBUG
if (debug)
printf("readudp: bad udp len %d < %d\n",
ntohs(uh->uh_ulen), (int)sizeof(*uh));
#endif
return -1;
}
n -= sizeof(*ip) + sizeof(*uh);
return (n);
}
/*
* Send a packet and wait for a reply, with exponential backoff.
*
* The send routine must return the actual number of bytes written,
* or -1 on error.
*
* The receive routine can indicate success by returning the number of
* bytes read; it can return 0 to indicate EOF; it can return -1 with a
* non-zero errno to indicate failure; finally, it can return -1 with a
* zero errno to indicate it isn't done yet.
*/
ssize_t
sendrecv(d, sproc, sbuf, ssize, rproc, rbuf, rsize)
register struct iodesc *d;
register ssize_t (*sproc)(struct iodesc *, void *, size_t);
register void *sbuf;
register size_t ssize;
register ssize_t (*rproc)(struct iodesc *, void *, size_t, time_t);
register void *rbuf;
register size_t rsize;
{
register ssize_t cc;
register time_t t, tmo, tlast;
long tleft;
#ifdef NET_DEBUG
if (debug)
printf("sendrecv: called\n");
#endif
tmo = MINTMO;
tlast = tleft = 0;
t = getsecs();
for (;;) {
if (tleft <= 0) {
if (tmo >= MAXTMO) {
errno = ETIMEDOUT;
return -1;
}
cc = (*sproc)(d, sbuf, ssize);
if (cc != -1 && cc < ssize)
panic("sendrecv: short write! (%d < %d)",
cc, ssize);
tleft = tmo;
tmo <<= 1;
if (tmo > MAXTMO)
tmo = MAXTMO;
if (cc == -1) {
/* Error on transmit; wait before retrying */
while ((getsecs() - t) < tmo);
tleft = 0;
continue;
}
tlast = t;
}
/* Try to get a packet and process it. */
cc = (*rproc)(d, rbuf, rsize, tleft);
/* Return on data, EOF or real error. */
if (cc != -1 || errno != 0)
return (cc);
/* Timed out or didn't get the packet we're waiting for */
t = getsecs();
tleft -= t - tlast;
tlast = t;
}
}
/*
* Like inet_addr() in the C library, but we only accept base-10.
* Return values are in network order.
*/
n_long
inet_addr(cp)
char *cp;
{
register u_long val;
register int n;
register char c;
u_int parts[4];
register u_int *pp = parts;
for (;;) {
/*
* Collect number up to ``.''.
* Values are specified as for C:
* 0x=hex, 0=octal, other=decimal.
*/
val = 0;
while ((c = *cp) != '\0') {
if (c >= '0' && c <= '9') {
val = (val * 10) + (c - '0');
cp++;
continue;
}
break;
}
if (*cp == '.') {
/*
* Internet format:
* a.b.c.d
* a.b.c (with c treated as 16-bits)
* a.b (with b treated as 24 bits)
*/
if (pp >= parts + 3 || val > 0xff)
goto bad;
*pp++ = val, cp++;
} else
break;
}
/*
* Check for trailing characters.
*/
if (*cp != '\0')
goto bad;
/*
* Concoct the address according to
* the number of parts specified.
*/
n = pp - parts + 1;
switch (n) {
case 1: /* a -- 32 bits */
break;
case 2: /* a.b -- 8.24 bits */
if (val > 0xffffff)
goto bad;
val |= parts[0] << 24;
break;
case 3: /* a.b.c -- 8.8.16 bits */
if (val > 0xffff)
goto bad;
val |= (parts[0] << 24) | (parts[1] << 16);
break;
case 4: /* a.b.c.d -- 8.8.8.8 bits */
if (val > 0xff)
goto bad;
val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
break;
}
return (htonl(val));
bad:
return (htonl(INADDR_NONE));
}
char *
inet_ntoa(ia)
struct in_addr ia;
{
return (intoa(ia.s_addr));
}
/* Similar to inet_ntoa() */
char *
intoa(addr)
register n_long addr;
{
register char *cp;
register u_int byte;
register int n;
static char buf[17]; /* strlen(".255.255.255.255") + 1 */
NTOHL(addr);
cp = &buf[sizeof buf];
*--cp = '\0';
n = 4;
do {
byte = addr & 0xff;
*--cp = byte % 10 + '0';
byte /= 10;
if (byte > 0) {
*--cp = byte % 10 + '0';
byte /= 10;
if (byte > 0)
*--cp = byte + '0';
}
*--cp = '.';
addr >>= 8;
} while (--n > 0);
return (cp+1);
}
static char *
number(s, n)
char *s;
int *n;
{
for (*n = 0; isdigit(*s); s++)
*n = (*n * 10) + *s - '0';
return s;
}
n_long
ip_convertaddr(p)
char *p;
{
#define IP_ANYADDR 0
n_long addr = 0, n;
if (p == (char *)0 || *p == '\0')
return IP_ANYADDR;
p = number(p, &n);
addr |= (n << 24) & 0xff000000;
if (*p == '\0' || *p++ != '.')
return IP_ANYADDR;
p = number(p, &n);
addr |= (n << 16) & 0xff0000;
if (*p == '\0' || *p++ != '.')
return IP_ANYADDR;
p = number(p, &n);
addr |= (n << 8) & 0xff00;
if (*p == '\0' || *p++ != '.')
return IP_ANYADDR;
p = number(p, &n);
addr |= n & 0xff;
if (*p != '\0')
return IP_ANYADDR;
return htonl(addr);
}