/* $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 #include #ifdef _STANDALONE #include #else #include #endif #include #include #include #include #include #include #include #include #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); }