void slirp_input(const uint8_t *pkt, int pkt_len) { struct mbuf *m; int proto; if (pkt_len < ETH_HLEN) return; proto = ntohs(*(uint16_t *)(pkt + 12)); switch(proto) { case ETH_P_ARP: arp_input(pkt, pkt_len); break; case ETH_P_IP: m = m_get(); if (!m) return; if (M_FREEROOM(m) < pkt_len + 2) { m_inc(m, pkt_len + 2); } m->m_len = pkt_len + 2; memcpy(m->m_data + 2, pkt, pkt_len); m->m_data += 2 + ETH_HLEN; m->m_len -= 2 + ETH_HLEN; ip_input(m); break; default: break; } }
/* * Copy len bytes from m, starting off bytes into n */ int m_copy(struct mbuf *n, struct mbuf *m, int off, int len) { if (len > M_FREEROOM(n)) return -1; memcpy((n->m_data + n->m_len), (m->m_data + off), len); n->m_len += len; return 0; }
void m_cat(struct mbuf *m, struct mbuf *n) { if (M_FREEROOM(m) < n->m_len) m_inc(m,m->m_size+MINCSIZE); memcpy(m->m_data+m->m_len, n->m_data, n->m_len); m->m_len += n->m_len; m_free(n); }
/* * Copy data from one mbuf to the end of * the other.. if result is too big for one mbuf, malloc() * an M_EXT data segment */ void m_cat(struct mbuf *m, struct mbuf *n) { /* * If there's no room, realloc */ if (M_FREEROOM(m) < n->m_len) m_inc(m,m->m_size+MINCSIZE); memcpy(m->m_data+m->m_len, n->m_data, n->m_len); m->m_len += n->m_len; m_free(n); }
/* * recvfrom() a UDP socket */ void sorecvfrom(struct socket *so) { struct sockaddr_in addr; socklen_t addrlen = sizeof(struct sockaddr_in); DEBUG_CALL("sorecvfrom"); DEBUG_ARG("so = %lx", (long)so); if (so->so_type == IPPROTO_ICMP) { /* This is a "ping" reply */ char buff[256]; int len; len = recvfrom(so->s, buff, 256, 0, (struct sockaddr *)&addr, &addrlen); /* XXX Check if reply is "correct"? */ if(len == -1 || len == 0) { u_char code=ICMP_UNREACH_PORT; if(errno == EHOSTUNREACH) code=ICMP_UNREACH_HOST; else if(errno == ENETUNREACH) code=ICMP_UNREACH_NET; DEBUG_MISC((dfd," udp icmp rx errno = %d-%s\n", errno,strerror(errno))); icmp_error(so->so_m, ICMP_UNREACH,code, 0,strerror(errno)); } else { icmp_reflect(so->so_m); so->so_m = NULL; /* Don't m_free() it again! */ } /* No need for this socket anymore, udp_detach it */ udp_detach(so); } else { /* A "normal" UDP packet */ struct mbuf *m; int len; #ifdef _WIN32 unsigned long n; #else int n; #endif m = m_get(so->slirp); if (!m) { return; } m->m_data += IF_MAXLINKHDR; /* * XXX Shouldn't FIONREAD packets destined for port 53, * but I don't know the max packet size for DNS lookups */ len = M_FREEROOM(m); /* if (so->so_fport != htons(53)) { */ ioctlsocket(so->s, FIONREAD, &n); if (n > len) { n = (m->m_data - m->m_dat) + m->m_len + n + 1; m_inc(m, n); len = M_FREEROOM(m); } /* } */ m->m_len = recvfrom(so->s, m->m_data, len, 0, (struct sockaddr *)&addr, &addrlen); DEBUG_MISC((dfd, " did recvfrom %d, errno = %d-%s\n", m->m_len, errno,strerror(errno))); if(m->m_len<0) { u_char code=ICMP_UNREACH_PORT; if(errno == EHOSTUNREACH) code=ICMP_UNREACH_HOST; else if(errno == ENETUNREACH) code=ICMP_UNREACH_NET; DEBUG_MISC((dfd," rx error, tx icmp ICMP_UNREACH:%i\n", code)); icmp_error(so->so_m, ICMP_UNREACH,code, 0,strerror(errno)); m_free(m); } else { /* * Hack: domain name lookup will be used the most for UDP, * and since they'll only be used once there's no need * for the 4 minute (or whatever) timeout... So we time them * out much quicker (10 seconds for now...) */ if (so->so_expire) { if (so->so_fport == htons(53)) so->so_expire = curtime + SO_EXPIREFAST; else so->so_expire = curtime + SO_EXPIRE; } /* * If this packet was destined for CTL_ADDR, * make it look like that's where it came from, done by udp_output */ udp_output(so, m, &addr); } /* rx error */ } /* if ping packet */ }
/* * recvfrom() a UDP socket */ void sorecvfrom(struct socket *so) { struct sockaddr_storage addr; struct sockaddr_storage saddr, daddr; socklen_t addrlen = sizeof(struct sockaddr_storage); DEBUG_CALL("sorecvfrom"); DEBUG_ARG("so = %p", so); if (so->so_type == IPPROTO_ICMP) { /* This is a "ping" reply */ char buff[256]; int len; len = recvfrom(so->s, buff, 256, 0, (struct sockaddr *)&addr, &addrlen); /* XXX Check if reply is "correct"? */ if(len == -1 || len == 0) { u_char code=ICMP_UNREACH_PORT; if(errno == EHOSTUNREACH) code=ICMP_UNREACH_HOST; else if(errno == ENETUNREACH) code=ICMP_UNREACH_NET; DEBUG_MISC((dfd," udp icmp rx errno = %d-%s\n", errno,strerror(errno))); icmp_send_error(so->so_m, ICMP_UNREACH, code, 0, strerror(errno)); } else { icmp_reflect(so->so_m); so->so_m = NULL; /* Don't m_free() it again! */ } /* No need for this socket anymore, udp_detach it */ udp_detach(so); } else { /* A "normal" UDP packet */ struct mbuf *m; int len; #ifdef _WIN32 unsigned long n; #else int n; #endif m = m_get(so->slirp); if (!m) { return; } switch (so->so_ffamily) { case AF_INET: m->m_data += IF_MAXLINKHDR + sizeof(struct udpiphdr); break; case AF_INET6: m->m_data += IF_MAXLINKHDR + sizeof(struct ip6) + sizeof(struct udphdr); break; default: g_assert_not_reached(); break; } /* * XXX Shouldn't FIONREAD packets destined for port 53, * but I don't know the max packet size for DNS lookups */ len = M_FREEROOM(m); /* if (so->so_fport != htons(53)) { */ ioctlsocket(so->s, FIONREAD, &n); if (n > len) { n = (m->m_data - m->m_dat) + m->m_len + n + 1; m_inc(m, n); len = M_FREEROOM(m); } /* } */ m->m_len = recvfrom(so->s, m->m_data, len, 0, (struct sockaddr *)&addr, &addrlen); DEBUG_MISC((dfd, " did recvfrom %d, errno = %d-%s\n", m->m_len, errno,strerror(errno))); if(m->m_len<0) { /* Report error as ICMP */ switch (so->so_lfamily) { uint8_t code; case AF_INET: code = ICMP_UNREACH_PORT; if (errno == EHOSTUNREACH) { code = ICMP_UNREACH_HOST; } else if (errno == ENETUNREACH) { code = ICMP_UNREACH_NET; } DEBUG_MISC((dfd, " rx error, tx icmp ICMP_UNREACH:%i\n", code)); icmp_send_error(so->so_m, ICMP_UNREACH, code, 0, strerror(errno)); break; case AF_INET6: code = ICMP6_UNREACH_PORT; if (errno == EHOSTUNREACH) { code = ICMP6_UNREACH_ADDRESS; } else if (errno == ENETUNREACH) { code = ICMP6_UNREACH_NO_ROUTE; } DEBUG_MISC((dfd, " rx error, tx icmp6 ICMP_UNREACH:%i\n", code)); icmp6_send_error(so->so_m, ICMP6_UNREACH, code); break; default: g_assert_not_reached(); break; } m_free(m); } else { /* * Hack: domain name lookup will be used the most for UDP, * and since they'll only be used once there's no need * for the 4 minute (or whatever) timeout... So we time them * out much quicker (10 seconds for now...) */ if (so->so_expire) { if (so->so_fport == htons(53)) so->so_expire = curtime + SO_EXPIREFAST; else so->so_expire = curtime + SO_EXPIRE; } /* * If this packet was destined for CTL_ADDR, * make it look like that's where it came from */ saddr = addr; sotranslate_in(so, &saddr); daddr = so->lhost.ss; switch (so->so_ffamily) { case AF_INET: udp_output(so, m, (struct sockaddr_in *) &saddr, (struct sockaddr_in *) &daddr, so->so_iptos); break; case AF_INET6: udp6_output(so, m, (struct sockaddr_in6 *) &saddr, (struct sockaddr_in6 *) &daddr); break; default: g_assert_not_reached(); break; } } /* rx error */ } /* if ping packet */ }