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-rw-r--r--slirp/udp.c654
1 files changed, 654 insertions, 0 deletions
diff --git a/slirp/udp.c b/slirp/udp.c
new file mode 100644
index 0000000000..76a4fcc97a
--- /dev/null
+++ b/slirp/udp.c
@@ -0,0 +1,654 @@
+/*
+ * 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;
+}
generated by cgit v1.2.3 (git 2.26.2) at 2024-11-30 19:01:39 +0000