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author | bellard <bellard@c046a42c-6fe2-441c-8c8c-71466251a162> | 2004-04-22 00:10:48 +0000 |
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committer | bellard <bellard@c046a42c-6fe2-441c-8c8c-71466251a162> | 2004-04-22 00:10:48 +0000 |
commit | 29aca44171f9b91be2bdac808e8cb94a8f544124 (patch) | |
tree | 6e2815081a389e8e08e5d29ec31631d89bbcffab /udp.c | |
download | slirp-29aca44171f9b91be2bdac808e8cb94a8f544124.zip slirp-29aca44171f9b91be2bdac808e8cb94a8f544124.tar.gz slirp-29aca44171f9b91be2bdac808e8cb94a8f544124.tar.bz2 |
initial user mode network support
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@733 c046a42c-6fe2-441c-8c8c-71466251a162
Diffstat (limited to 'udp.c')
-rw-r--r-- | udp.c | 642 |
1 files changed, 642 insertions, 0 deletions
@@ -0,0 +1,642 @@ +/* + * Copyright (c) 1982, 1986, 1988, 1990, 1993 + * The Regents of the University of California. 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 University of + * California, Berkeley 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. + * + * @(#)udp_usrreq.c 8.4 (Berkeley) 1/21/94 + * udp_usrreq.c,v 1.4 1994/10/02 17:48:45 phk Exp + */ + +/* + * Changes and additions relating to SLiRP + * Copyright (c) 1995 Danny Gasparovski. + * + * Please read the file COPYRIGHT for the + * terms and conditions of the copyright. + */ + +#include <slirp.h> +#include "ip_icmp.h" + +struct udpstat udpstat; + +struct socket udb; + +/* + * UDP protocol implementation. + * Per RFC 768, August, 1980. + */ +#ifndef COMPAT_42 +int udpcksum = 1; +#else +int udpcksum = 0; /* XXX */ +#endif + +struct socket *udp_last_so = &udb; + +void udp_init() +{ + udb.so_next = udb.so_prev = &udb; +} +/* m->m_data points at ip packet header + * m->m_len length ip packet + * ip->ip_len length data (IPDU) + */ +void udp_input(m, iphlen) register struct mbuf *m; +int iphlen; +{ + register struct ip *ip; + register struct udphdr *uh; + /* struct mbuf *opts = 0;*/ + int len; + struct ip save_ip; + struct socket *so; + + DEBUG_CALL("udp_input"); + DEBUG_ARG("m = %lx", (long)m); + DEBUG_ARG("iphlen = %d", iphlen); + + udpstat.udps_ipackets++; + + /* + * Strip IP options, if any; should skip this, + * make available to user, and use on returned packets, + * but we don't yet have a way to check the checksum + * with options still present. + */ + if (iphlen > sizeof(struct ip)) { + ip_stripoptions(m, (struct mbuf *)0); + iphlen = sizeof(struct ip); + } + + /* + * Get IP and UDP header together in first mbuf. + */ + ip = mtod(m, struct ip *); + uh = (struct udphdr *)((caddr_t)ip + iphlen); + + /* + * Make mbuf data length reflect UDP length. + * If not enough data to reflect UDP length, drop. + */ + len = ntohs((u_int16_t)uh->uh_ulen); + + if (ip->ip_len != len) { + if (len > ip->ip_len) { + udpstat.udps_badlen++; + goto bad; + } + m_adj(m, len - ip->ip_len); + ip->ip_len = len; + } + + /* + * Save a copy of the IP header in case we want restore it + * for sending an ICMP error message in response. + */ + save_ip = *ip; + save_ip.ip_len += iphlen; /* tcp_input subtracts this */ + + /* + * Checksum extended UDP header and data. + */ + if (udpcksum && uh->uh_sum) { + ((struct ipovly *)ip)->ih_next = 0; + ((struct ipovly *)ip)->ih_prev = 0; + ((struct ipovly *)ip)->ih_x1 = 0; + ((struct ipovly *)ip)->ih_len = uh->uh_ulen; + /* keep uh_sum for ICMP reply + * uh->uh_sum = cksum(m, len + sizeof (struct ip)); + * if (uh->uh_sum) { + */ + if (cksum(m, len + sizeof(struct ip))) { + udpstat.udps_badsum++; + goto bad; + } + } + + /* + * handle DHCP/BOOTP + */ + if (ntohs(uh->uh_dport) == BOOTP_SERVER) { + bootp_input(m); + goto bad; + } + + /* + * Locate pcb for datagram. + */ + so = udp_last_so; + if (so->so_lport != uh->uh_sport || + so->so_laddr.s_addr != ip->ip_src.s_addr) { + struct socket *tmp; + + for (tmp = udb.so_next; tmp != &udb; tmp = tmp->so_next) { + if (tmp->so_lport == uh->uh_sport && + tmp->so_laddr.s_addr == ip->ip_src.s_addr) { + tmp->so_faddr.s_addr = ip->ip_dst.s_addr; + tmp->so_fport = uh->uh_dport; + so = tmp; + break; + } + } + if (tmp == &udb) { + so = NULL; + } else { + udpstat.udpps_pcbcachemiss++; + udp_last_so = so; + } + } + + if (so == NULL) { + /* + * If there's no socket for this packet, + * create one + */ + if ((so = socreate()) == NULL) + goto bad; + if (udp_attach(so) == -1) { + DEBUG_MISC( + (dfd, " udp_attach errno = %d-%s\n", errno, strerror(errno))); + sofree(so); + goto bad; + } + + /* + * Setup fields + */ + /* udp_last_so = so; */ + so->so_laddr = ip->ip_src; + so->so_lport = uh->uh_sport; + so->so_faddr = ip->ip_dst; /* XXX */ + so->so_fport = uh->uh_dport; /* XXX */ + + if ((so->so_iptos = udp_tos(so)) == 0) + so->so_iptos = ip->ip_tos; + + /* + * XXXXX Here, check if it's in udpexec_list, + * and if it is, do the fork_exec() etc. + */ + } + + iphlen += sizeof(struct udphdr); + m->m_len -= iphlen; + m->m_data += iphlen; + + /* + * Now we sendto() the packet. + */ + if (so->so_emu) + udp_emu(so, m); + + if (sosendto(so, m) == -1) { + m->m_len += iphlen; + m->m_data -= iphlen; + *ip = save_ip; + DEBUG_MISC((dfd, "udp tx errno = %d-%s\n", errno, strerror(errno))); + icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_NET, 0, strerror(errno)); + } + + m_free(so->so_m); /* used for ICMP if error on sorecvfrom */ + + /* restore the orig mbuf packet */ + m->m_len += iphlen; + m->m_data -= iphlen; + *ip = save_ip; + so->so_m = m; /* ICMP backup */ + + return; +bad: + m_freem(m); + /* if (opts) m_freem(opts); */ + return; +} + +int udp_output2(struct socket *so, struct mbuf *m, struct sockaddr_in *saddr, + struct sockaddr_in *daddr, int iptos) +{ + register struct udpiphdr *ui; + int error = 0; + + DEBUG_CALL("udp_output"); + DEBUG_ARG("so = %lx", (long)so); + DEBUG_ARG("m = %lx", (long)m); + DEBUG_ARG("saddr = %lx", (long)saddr->sin_addr.s_addr); + DEBUG_ARG("daddr = %lx", (long)daddr->sin_addr.s_addr); + + /* + * Adjust for header + */ + m->m_data -= sizeof(struct udpiphdr); + m->m_len += sizeof(struct udpiphdr); + + /* + * Fill in mbuf with extended UDP header + * and addresses and length put into network format. + */ + ui = mtod(m, struct udpiphdr *); + ui->ui_next = ui->ui_prev = 0; + ui->ui_x1 = 0; + ui->ui_pr = IPPROTO_UDP; + ui->ui_len = + htons(m->m_len - sizeof(struct ip)); /* + sizeof (struct udphdr)); */ + /* XXXXX Check for from-one-location sockets, or from-any-location sockets + */ + ui->ui_src = saddr->sin_addr; + ui->ui_dst = daddr->sin_addr; + ui->ui_sport = saddr->sin_port; + ui->ui_dport = daddr->sin_port; + ui->ui_ulen = ui->ui_len; + + /* + * Stuff checksum and output datagram. + */ + ui->ui_sum = 0; + if (udpcksum) { + if ((ui->ui_sum = + cksum(m, /* sizeof (struct udpiphdr) + */ m->m_len)) == 0) + ui->ui_sum = 0xffff; + } + ((struct ip *)ui)->ip_len = m->m_len; + + ((struct ip *)ui)->ip_ttl = ip_defttl; + ((struct ip *)ui)->ip_tos = iptos; + + udpstat.udps_opackets++; + + error = ip_output(so, m); + + return (error); +} + +int udp_output(struct socket *so, struct mbuf *m, struct sockaddr_in *addr) + +{ + struct sockaddr_in saddr, daddr; + + saddr = *addr; + if ((so->so_faddr.s_addr & htonl(0xffffff00)) == special_addr.s_addr) + saddr.sin_addr.s_addr = so->so_faddr.s_addr; + daddr.sin_addr = so->so_laddr; + daddr.sin_port = so->so_lport; + + return udp_output2(so, m, &saddr, &daddr, so->so_iptos); +} + +int udp_attach(so) struct socket *so; +{ + struct sockaddr_in addr; + + if ((so->s = socket(AF_INET, SOCK_DGRAM, 0)) != -1) { + /* + * Here, we bind() the socket. Although not really needed + * (sendto() on an unbound socket will bind it), it's done + * here so that emulation of ytalk etc. don't have to do it + */ + addr.sin_family = AF_INET; + addr.sin_port = 0; + addr.sin_addr.s_addr = INADDR_ANY; + if (bind(so->s, (struct sockaddr *)&addr, sizeof(addr)) < 0) { + int lasterrno = errno; + close(so->s); + so->s = -1; + errno = lasterrno; + } else { + /* success, insert in queue */ + so->so_expire = curtime + SO_EXPIRE; + insque(so, &udb); + } + } + return (so->s); +} + +void udp_detach(so) struct socket *so; +{ + close(so->s); + /* if (so->so_m) m_free(so->so_m); done by sofree */ + + sofree(so); +} + +struct tos_t udptos[] = { { 0, 53, IPTOS_LOWDELAY, 0 }, /* DNS */ + { 517, 517, IPTOS_LOWDELAY, EMU_TALK }, /* talk */ + { 518, 518, IPTOS_LOWDELAY, EMU_NTALK }, /* ntalk */ + { 0, 7648, IPTOS_LOWDELAY, + EMU_CUSEEME }, /* Cu-Seeme */ + { 0, 0, 0, 0 } }; + +u_int8_t udp_tos(so) struct socket *so; +{ + int i = 0; + + while (udptos[i].tos) { + if ((udptos[i].fport && ntohs(so->so_fport) == udptos[i].fport) || + (udptos[i].lport && ntohs(so->so_lport) == udptos[i].lport)) { + so->so_emu = udptos[i].emu; + return udptos[i].tos; + } + i++; + } + + return 0; +} + +#ifdef EMULATE_TALK +#include "talkd.h" +#endif + +/* + * Here, talk/ytalk/ntalk requests must be emulated + */ +void udp_emu(so, m) struct socket *so; +struct mbuf *m; +{ + struct sockaddr_in addr; + int addrlen = sizeof(addr); +#ifdef EMULATE_TALK + CTL_MSG_OLD *omsg; + CTL_MSG *nmsg; + char buff[sizeof(CTL_MSG)]; + u_char type; + + struct talk_request { + struct talk_request *next; + struct socket *udp_so; + struct socket *tcp_so; + } * req; + + static struct talk_request *req_tbl = 0; + +#endif + + struct cu_header { + char dest[8]; + short family; + u_short port; + u_long addr; + } * cu_head; + + switch (so->so_emu) { +#ifdef EMULATE_TALK + case EMU_TALK: + case EMU_NTALK: + /* + * Talk emulation. We always change the ctl_addr to get + * some answers from the daemon. When an ANNOUNCE comes, + * we send LEAVE_INVITE to the local daemons. Also when a + * DELETE comes, we send copies to the local daemons. + */ + if (getsockname(so->s, (struct sockaddr *)&addr, &addrlen) < 0) + return; + +#define IS_OLD (so->so_emu == EMU_TALK) + +#define COPY_MSG(dest, src) \ + { \ + dest->type = src->type; \ + dest->id_num = src->id_num; \ + dest->pid = src->pid; \ + dest->addr = src->addr; \ + dest->ctl_addr = src->ctl_addr; \ + memcpy(&dest->l_name, &src->l_name, NAME_SIZE_OLD); \ + memcpy(&dest->r_name, &src->r_name, NAME_SIZE_OLD); \ + memcpy(&dest->r_tty, &src->r_tty, TTY_SIZE); \ + } + +#define OTOSIN(ptr, field) ((struct sockaddr_in *)&ptr->field) + /* old_sockaddr to sockaddr_in */ + + + if (IS_OLD) { /* old talk */ + omsg = mtod(m, CTL_MSG_OLD *); + nmsg = (CTL_MSG *)buff; + type = omsg->type; + OTOSIN(omsg, ctl_addr)->sin_port = addr.sin_port; + OTOSIN(omsg, ctl_addr)->sin_addr = our_addr; + strncpy(omsg->l_name, getlogin(), NAME_SIZE_OLD); + } else { /* new talk */ + omsg = (CTL_MSG_OLD *)buff; + nmsg = mtod(m, CTL_MSG *); + type = nmsg->type; + OTOSIN(nmsg, ctl_addr)->sin_port = addr.sin_port; + OTOSIN(nmsg, ctl_addr)->sin_addr = our_addr; + strncpy(nmsg->l_name, getlogin(), NAME_SIZE_OLD); + } + + if (type == LOOK_UP) + return; /* for LOOK_UP this is enough */ + + if (IS_OLD) { /* make a copy of the message */ + COPY_MSG(nmsg, omsg); + nmsg->vers = 1; + nmsg->answer = 0; + } else + COPY_MSG(omsg, nmsg); + + /* + * If if is an ANNOUNCE message, we go through the + * request table to see if a tcp port has already + * been redirected for this socket. If not, we solisten() + * a new socket and add this entry to the table. + * The port number of the tcp socket and our IP + * are put to the addr field of the message structures. + * Then a LEAVE_INVITE is sent to both local daemon + * ports, 517 and 518. This is why we have two copies + * of the message, one in old talk and one in new talk + * format. + */ + + if (type == ANNOUNCE) { + int s; + u_short temp_port; + + for (req = req_tbl; req; req = req->next) + if (so == req->udp_so) + break; /* found it */ + + if (!req) { /* no entry for so, create new */ + req = + (struct talk_request *)malloc(sizeof(struct talk_request)); + req->udp_so = so; + req->tcp_so = + solisten(0, OTOSIN(omsg, addr)->sin_addr.s_addr, + OTOSIN(omsg, addr)->sin_port, SS_FACCEPTONCE); + req->next = req_tbl; + req_tbl = req; + } + + /* replace port number in addr field */ + addrlen = sizeof(addr); + getsockname(req->tcp_so->s, (struct sockaddr *)&addr, &addrlen); + OTOSIN(omsg, addr)->sin_port = addr.sin_port; + OTOSIN(omsg, addr)->sin_addr = our_addr; + OTOSIN(nmsg, addr)->sin_port = addr.sin_port; + OTOSIN(nmsg, addr)->sin_addr = our_addr; + + /* send LEAVE_INVITEs */ + temp_port = OTOSIN(omsg, ctl_addr)->sin_port; + OTOSIN(omsg, ctl_addr)->sin_port = 0; + OTOSIN(nmsg, ctl_addr)->sin_port = 0; + omsg->type = nmsg->type = LEAVE_INVITE; + + s = socket(AF_INET, SOCK_DGRAM, IPPROTO_IP); + addr.sin_addr = our_addr; + addr.sin_family = AF_INET; + addr.sin_port = htons(517); + sendto(s, (char *)omsg, sizeof(*omsg), 0, (struct sockaddr *)&addr, + sizeof(addr)); + addr.sin_port = htons(518); + sendto(s, (char *)nmsg, sizeof(*nmsg), 0, (struct sockaddr *)&addr, + sizeof(addr)); + close(s); + + omsg->type = nmsg->type = ANNOUNCE; + OTOSIN(omsg, ctl_addr)->sin_port = temp_port; + OTOSIN(nmsg, ctl_addr)->sin_port = temp_port; + } + + /* + * If it is a DELETE message, we send a copy to the + * local daemons. Then we delete the entry corresponding + * to our socket from the request table. + */ + + if (type == DELETE) { + struct talk_request *temp_req, *req_next; + int s; + u_short temp_port; + + temp_port = OTOSIN(omsg, ctl_addr)->sin_port; + OTOSIN(omsg, ctl_addr)->sin_port = 0; + OTOSIN(nmsg, ctl_addr)->sin_port = 0; + + s = socket(AF_INET, SOCK_DGRAM, IPPROTO_IP); + addr.sin_addr = our_addr; + addr.sin_family = AF_INET; + addr.sin_port = htons(517); + sendto(s, (char *)omsg, sizeof(*omsg), 0, (struct sockaddr *)&addr, + sizeof(addr)); + addr.sin_port = htons(518); + sendto(s, (char *)nmsg, sizeof(*nmsg), 0, (struct sockaddr *)&addr, + sizeof(addr)); + close(s); + + OTOSIN(omsg, ctl_addr)->sin_port = temp_port; + OTOSIN(nmsg, ctl_addr)->sin_port = temp_port; + + /* delete table entry */ + if (so == req_tbl->udp_so) { + temp_req = req_tbl; + req_tbl = req_tbl->next; + free(temp_req); + } else { + temp_req = req_tbl; + for (req = req_tbl->next; req; req = req_next) { + req_next = req->next; + if (so == req->udp_so) { + temp_req->next = req_next; + free(req); + break; + } else { + temp_req = req; + } + } + } + } + + return; +#endif + + case EMU_CUSEEME: + + /* + * Cu-SeeMe emulation. + * Hopefully the packet is more that 16 bytes long. We don't + * do any other tests, just replace the address and port + * fields. + */ + if (m->m_len >= sizeof(*cu_head)) { + if (getsockname(so->s, (struct sockaddr *)&addr, &addrlen) < 0) + return; + cu_head = mtod(m, struct cu_header *); + cu_head->port = addr.sin_port; + cu_head->addr = (u_long)our_addr.s_addr; + } + + return; + } +} + +struct socket *udp_listen(port, laddr, lport, flags) u_int port; +u_int32_t laddr; +u_int lport; +int flags; +{ + struct sockaddr_in addr; + struct socket *so; + int addrlen = sizeof(struct sockaddr_in), opt = 1; + + if ((so = socreate()) == NULL) { + free(so); + return NULL; + } + so->s = socket(AF_INET, SOCK_DGRAM, 0); + so->so_expire = curtime + SO_EXPIRE; + insque(so, &udb); + + addr.sin_family = AF_INET; + addr.sin_addr.s_addr = INADDR_ANY; + addr.sin_port = port; + + if (bind(so->s, (struct sockaddr *)&addr, addrlen) < 0) { + udp_detach(so); + return NULL; + } + setsockopt(so->s, SOL_SOCKET, SO_REUSEADDR, (char *)&opt, sizeof(int)); + /* setsockopt(so->s,SOL_SOCKET,SO_OOBINLINE,(char *)&opt,sizeof(int)); */ + + getsockname(so->s, (struct sockaddr *)&addr, &addrlen); + so->so_fport = addr.sin_port; + if (addr.sin_addr.s_addr == 0 || + addr.sin_addr.s_addr == loopback_addr.s_addr) + so->so_faddr = our_addr; + else + so->so_faddr = addr.sin_addr; + + so->so_lport = lport; + so->so_laddr.s_addr = laddr; + if (flags != SS_FACCEPTONCE) + so->so_expire = 0; + + so->so_state = SS_ISFCONNECTED; + + return so; +} |