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 = %p", 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_ffamily = AF_INET; so->so_faddr = ip->ip_dst; so->so_fport = htons(7); so->so_lfamily = AF_INET; 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; }