--- /dev/null
+/*
+ * Copyright (c) 1982, 1986, 1988, 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. 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.
+ *
+ * @(#)ip_icmp.c 8.2 (Berkeley) 1/4/94
+ * ip_icmp.c,v 1.7 1995/05/30 08:09:42 rgrimes Exp
+ */
+
+#include "slirp.h"
+#include "ip_icmp.h"
+
+/* The message sent when emulating PING */
+/* Be nice and tell them it's just a pseudo-ping packet */
+static const char icmp_ping_msg[] = "This is a pseudo-PING packet used by Slirp to emulate ICMP ECHO-REQUEST packets.\n";
+
+/* list of actions for icmp_error() on RX of an icmp message */
+static const int icmp_flush[19] = {
+/* ECHO REPLY (0) */ 0,
+ 1,
+ 1,
+/* DEST UNREACH (3) */ 1,
+/* SOURCE QUENCH (4)*/ 1,
+/* REDIRECT (5) */ 1,
+ 1,
+ 1,
+/* ECHO (8) */ 0,
+/* ROUTERADVERT (9) */ 1,
+/* ROUTERSOLICIT (10) */ 1,
+/* TIME EXCEEDED (11) */ 1,
+/* PARAMETER PROBLEM (12) */ 1,
+/* TIMESTAMP (13) */ 0,
+/* TIMESTAMP REPLY (14) */ 0,
+/* INFO (15) */ 0,
+/* INFO REPLY (16) */ 0,
+/* ADDR MASK (17) */ 0,
+/* ADDR MASK REPLY (18) */ 0
+};
+
+void icmp_init(Slirp *slirp)
+{
+ slirp->icmp.so_next = slirp->icmp.so_prev = &slirp->icmp;
+ slirp->icmp_last_so = &slirp->icmp;
+}
+
+void icmp_cleanup(Slirp *slirp)
+{
+ while (slirp->icmp.so_next != &slirp->icmp) {
+ icmp_detach(slirp->icmp.so_next);
+ }
+}
+
+static int icmp_send(struct socket *so, struct mbuf *m, int hlen)
+{
+ struct ip *ip = mtod(m, struct ip *);
+ struct sockaddr_in addr;
+
+ so->s = qemu_socket(AF_INET, SOCK_DGRAM, IPPROTO_ICMP);
+ if (so->s == -1) {
+ return -1;
+ }
+
+ so->so_m = m;
+ so->so_faddr = ip->ip_dst;
+ so->so_laddr = ip->ip_src;
+ so->so_iptos = ip->ip_tos;
+ so->so_type = IPPROTO_ICMP;
+ so->so_state = SS_ISFCONNECTED;
+ so->so_expire = curtime + SO_EXPIRE;
+
+ addr.sin_family = AF_INET;
+ addr.sin_addr = so->so_faddr;
+
+ insque(so, &so->slirp->icmp);
+
+ if (sendto(so->s, m->m_data + hlen, m->m_len - hlen, 0,
+ (struct sockaddr *)&addr, sizeof(addr)) == -1) {
+ DEBUG_MISC((dfd, "icmp_input icmp sendto tx errno = %d-%s\n",
+ errno, strerror(errno)));
+ icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_NET, 0, strerror(errno));
+ icmp_detach(so);
+ }
+
+ return 0;
+}
+
+void icmp_detach(struct socket *so)
+{
+ closesocket(so->s);
+ sofree(so);
+}
+
+/*
+ * Process a received ICMP message.
+ */
+void
+icmp_input(struct mbuf *m, int hlen)
+{
+ register struct icmp *icp;
+ register struct ip *ip=mtod(m, struct ip *);
+ int icmplen=ip->ip_len;
+ Slirp *slirp = m->slirp;
+
+ DEBUG_CALL("icmp_input");
+ DEBUG_ARG("m = %lx", (long )m);
+ DEBUG_ARG("m_len = %d", m->m_len);
+
+ /*
+ * Locate icmp structure in mbuf, and check
+ * that its not corrupted and of at least minimum length.
+ */
+ if (icmplen < ICMP_MINLEN) { /* min 8 bytes payload */
+ freeit:
+ m_free(m);
+ goto end_error;
+ }
+
+ m->m_len -= hlen;
+ m->m_data += hlen;
+ icp = mtod(m, struct icmp *);
+ if (cksum(m, icmplen)) {
+ goto freeit;
+ }
+ m->m_len += hlen;
+ m->m_data -= hlen;
+
+ DEBUG_ARG("icmp_type = %d", icp->icmp_type);
+ switch (icp->icmp_type) {
+ case ICMP_ECHO:
+ ip->ip_len += hlen; /* since ip_input subtracts this */
+ if (ip->ip_dst.s_addr == slirp->vhost_addr.s_addr) {
+ icmp_reflect(m);
+ } else if (slirp->restricted) {
+ goto freeit;
+ } else {
+ struct socket *so;
+ struct sockaddr_in addr;
+ if ((so = socreate(slirp)) == NULL) goto freeit;
+ if (icmp_send(so, m, hlen) == 0) {
+ return;
+ }
+ if(udp_attach(so) == -1) {
+ DEBUG_MISC((dfd,"icmp_input udp_attach errno = %d-%s\n",
+ errno,strerror(errno)));
+ sofree(so);
+ m_free(m);
+ goto end_error;
+ }
+ so->so_m = m;
+ so->so_faddr = ip->ip_dst;
+ so->so_fport = htons(7);
+ so->so_laddr = ip->ip_src;
+ so->so_lport = htons(9);
+ so->so_iptos = ip->ip_tos;
+ so->so_type = IPPROTO_ICMP;
+ so->so_state = SS_ISFCONNECTED;
+
+ /* Send the packet */
+ addr.sin_family = AF_INET;
+ if ((so->so_faddr.s_addr & slirp->vnetwork_mask.s_addr) ==
+ slirp->vnetwork_addr.s_addr) {
+ /* It's an alias */
+ if (so->so_faddr.s_addr == slirp->vnameserver_addr.s_addr) {
+ if (get_dns_addr(&addr.sin_addr) < 0)
+ addr.sin_addr = loopback_addr;
+ } else {
+ addr.sin_addr = loopback_addr;
+ }
+ } else {
+ addr.sin_addr = so->so_faddr;
+ }
+ addr.sin_port = so->so_fport;
+ if(sendto(so->s, icmp_ping_msg, strlen(icmp_ping_msg), 0,
+ (struct sockaddr *)&addr, sizeof(addr)) == -1) {
+ DEBUG_MISC((dfd,"icmp_input udp sendto tx errno = %d-%s\n",
+ errno,strerror(errno)));
+ icmp_error(m, ICMP_UNREACH,ICMP_UNREACH_NET, 0,strerror(errno));
+ udp_detach(so);
+ }
+ } /* if ip->ip_dst.s_addr == alias_addr.s_addr */
+ break;
+ case ICMP_UNREACH:
+ /* XXX? report error? close socket? */
+ case ICMP_TIMXCEED:
+ case ICMP_PARAMPROB:
+ case ICMP_SOURCEQUENCH:
+ case ICMP_TSTAMP:
+ case ICMP_MASKREQ:
+ case ICMP_REDIRECT:
+ m_free(m);
+ break;
+
+ default:
+ m_free(m);
+ } /* swith */
+
+end_error:
+ /* m is m_free()'d xor put in a socket xor or given to ip_send */
+ return;
+}
+
+
+/*
+ * Send an ICMP message in response to a situation
+ *
+ * RFC 1122: 3.2.2 MUST send at least the IP header and 8 bytes of header. MAY send more (we do).
+ * MUST NOT change this header information.
+ * MUST NOT reply to a multicast/broadcast IP address.
+ * MUST NOT reply to a multicast/broadcast MAC address.
+ * MUST reply to only the first fragment.
+ */
+/*
+ * Send ICMP_UNREACH back to the source regarding msrc.
+ * mbuf *msrc is used as a template, but is NOT m_free()'d.
+ * It is reported as the bad ip packet. The header should
+ * be fully correct and in host byte order.
+ * ICMP fragmentation is illegal. All machines must accept 576 bytes in one
+ * packet. The maximum payload is 576-20(ip hdr)-8(icmp hdr)=548
+ */
+
+#define ICMP_MAXDATALEN (IP_MSS-28)
+void
+icmp_error(struct mbuf *msrc, u_char type, u_char code, int minsize,
+ const char *message)
+{
+ unsigned hlen, shlen, s_ip_len;
+ register struct ip *ip;
+ register struct icmp *icp;
+ register struct mbuf *m;
+
+ DEBUG_CALL("icmp_error");
+ DEBUG_ARG("msrc = %lx", (long )msrc);
+ DEBUG_ARG("msrc_len = %d", msrc->m_len);
+
+ if(type!=ICMP_UNREACH && type!=ICMP_TIMXCEED) goto end_error;
+
+ /* check msrc */
+ if(!msrc) goto end_error;
+ ip = mtod(msrc, struct ip *);
+#ifdef DEBUG
+ { char bufa[20], bufb[20];
+ strcpy(bufa, inet_ntoa(ip->ip_src));
+ strcpy(bufb, inet_ntoa(ip->ip_dst));
+ DEBUG_MISC((dfd, " %.16s to %.16s\n", bufa, bufb));
+ }
+#endif
+ if(ip->ip_off & IP_OFFMASK) goto end_error; /* Only reply to fragment 0 */
+
+ /* Do not reply to source-only IPs */
+ if ((ip->ip_src.s_addr & htonl(~(0xf << 28))) == 0) {
+ goto end_error;
+ }
+
+ shlen=ip->ip_hl << 2;
+ s_ip_len=ip->ip_len;
+ if(ip->ip_p == IPPROTO_ICMP) {
+ icp = (struct icmp *)((char *)ip + shlen);
+ /*
+ * Assume any unknown ICMP type is an error. This isn't
+ * specified by the RFC, but think about it..
+ */
+ if(icp->icmp_type>18 || icmp_flush[icp->icmp_type]) goto end_error;
+ }
+
+ /* make a copy */
+ m = m_get(msrc->slirp);
+ if (!m) {
+ goto end_error;
+ }
+
+ { int new_m_size;
+ new_m_size=sizeof(struct ip )+ICMP_MINLEN+msrc->m_len+ICMP_MAXDATALEN;
+ if(new_m_size>m->m_size) m_inc(m, new_m_size);
+ }
+ memcpy(m->m_data, msrc->m_data, msrc->m_len);
+ m->m_len = msrc->m_len; /* copy msrc to m */
+
+ /* make the header of the reply packet */
+ ip = mtod(m, struct ip *);
+ hlen= sizeof(struct ip ); /* no options in reply */
+
+ /* fill in icmp */
+ m->m_data += hlen;
+ m->m_len -= hlen;
+
+ icp = mtod(m, struct icmp *);
+
+ if(minsize) s_ip_len=shlen+ICMP_MINLEN; /* return header+8b only */
+ else if(s_ip_len>ICMP_MAXDATALEN) /* maximum size */
+ s_ip_len=ICMP_MAXDATALEN;
+
+ m->m_len=ICMP_MINLEN+s_ip_len; /* 8 bytes ICMP header */
+
+ /* min. size = 8+sizeof(struct ip)+8 */
+
+ icp->icmp_type = type;
+ icp->icmp_code = code;
+ icp->icmp_id = 0;
+ icp->icmp_seq = 0;
+
+ memcpy(&icp->icmp_ip, msrc->m_data, s_ip_len); /* report the ip packet */
+ HTONS(icp->icmp_ip.ip_len);
+ HTONS(icp->icmp_ip.ip_id);
+ HTONS(icp->icmp_ip.ip_off);
+
+#ifdef DEBUG
+ if(message) { /* DEBUG : append message to ICMP packet */
+ int message_len;
+ char *cpnt;
+ message_len=strlen(message);
+ if(message_len>ICMP_MAXDATALEN) message_len=ICMP_MAXDATALEN;
+ cpnt=(char *)m->m_data+m->m_len;
+ memcpy(cpnt, message, message_len);
+ m->m_len+=message_len;
+ }
+#endif
+
+ icp->icmp_cksum = 0;
+ icp->icmp_cksum = cksum(m, m->m_len);
+
+ m->m_data -= hlen;
+ m->m_len += hlen;
+
+ /* fill in ip */
+ ip->ip_hl = hlen >> 2;
+ ip->ip_len = m->m_len;
+
+ ip->ip_tos=((ip->ip_tos & 0x1E) | 0xC0); /* high priority for errors */
+
+ ip->ip_ttl = MAXTTL;
+ ip->ip_p = IPPROTO_ICMP;
+ ip->ip_dst = ip->ip_src; /* ip addresses */
+ ip->ip_src = m->slirp->vhost_addr;
+
+ (void ) ip_output((struct socket *)NULL, m);
+
+end_error:
+ return;
+}
+#undef ICMP_MAXDATALEN
+
+/*
+ * Reflect the ip packet back to the source
+ */
+void
+icmp_reflect(struct mbuf *m)
+{
+ register struct ip *ip = mtod(m, struct ip *);
+ int hlen = ip->ip_hl << 2;
+ int optlen = hlen - sizeof(struct ip );
+ register struct icmp *icp;
+
+ /*
+ * Send an icmp packet back to the ip level,
+ * after supplying a checksum.
+ */
+ m->m_data += hlen;
+ m->m_len -= hlen;
+ icp = mtod(m, struct icmp *);
+
+ icp->icmp_type = ICMP_ECHOREPLY;
+ icp->icmp_cksum = 0;
+ icp->icmp_cksum = cksum(m, ip->ip_len - hlen);
+
+ m->m_data -= hlen;
+ m->m_len += hlen;
+
+ /* fill in ip */
+ if (optlen > 0) {
+ /*
+ * Strip out original options by copying rest of first
+ * mbuf's data back, and adjust the IP length.
+ */
+ memmove((caddr_t)(ip + 1), (caddr_t)ip + hlen,
+ (unsigned )(m->m_len - hlen));
+ hlen -= optlen;
+ ip->ip_hl = hlen >> 2;
+ ip->ip_len -= optlen;
+ m->m_len -= optlen;
+ }
+
+ ip->ip_ttl = MAXTTL;
+ { /* swap */
+ struct in_addr icmp_dst;
+ icmp_dst = ip->ip_dst;
+ ip->ip_dst = ip->ip_src;
+ ip->ip_src = icmp_dst;
+ }
+
+ (void ) ip_output((struct socket *)NULL, m);
+}
+
+void icmp_receive(struct socket *so)
+{
+ struct mbuf *m = so->so_m;
+ struct ip *ip = mtod(m, struct ip *);
+ int hlen = ip->ip_hl << 2;
+ u_char error_code;
+ struct icmp *icp;
+ int id, len;
+
+ m->m_data += hlen;
+ m->m_len -= hlen;
+ icp = mtod(m, struct icmp *);
+
+ id = icp->icmp_id;
+ len = qemu_recv(so->s, icp, m->m_len, 0);
+ icp->icmp_id = id;
+
+ m->m_data -= hlen;
+ m->m_len += hlen;
+
+ if (len == -1 || len == 0) {
+ if (errno == ENETUNREACH) {
+ error_code = ICMP_UNREACH_NET;
+ } else {
+ error_code = ICMP_UNREACH_HOST;
+ }
+ DEBUG_MISC((dfd, " udp icmp rx errno = %d-%s\n", errno,
+ strerror(errno)));
+ icmp_error(so->so_m, ICMP_UNREACH, error_code, 0, strerror(errno));
+ } else {
+ icmp_reflect(so->so_m);
+ so->so_m = NULL; /* Don't m_free() it again! */
+ }
+ icmp_detach(so);
+}
Code Review / kvmfornfv.git / blobdiff