/* * 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. 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" static uint8_t udp_tos(struct socket *so); void udp_init(Slirp *slirp) { slirp->udb.so_next = slirp->udb.so_prev = &slirp->udb; slirp->udp_last_so = &slirp->udb; } void udp_cleanup(Slirp *slirp) { while (slirp->udb.so_next != &slirp->udb) { udp_detach(slirp->udb.so_next); } } /* m->m_data points at ip packet header * m->m_len length ip packet * ip->ip_len length data (IPDU) */ void udp_input(register struct mbuf *m, int iphlen) { Slirp *slirp = m->slirp; register struct ip *ip; register struct udphdr *uh; int len; struct ip save_ip; struct socket *so; DEBUG_CALL("udp_input"); DEBUG_ARG("m = %lx", (long)m); DEBUG_ARG("iphlen = %d", iphlen); /* * 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((uint16_t)uh->uh_ulen); if (ip->ip_len != len) { if (len > ip->ip_len) { 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 (uh->uh_sum) { memset(&((struct ipovly *)ip)->ih_mbuf, 0, sizeof(struct mbuf_ptr)); ((struct ipovly *)ip)->ih_x1 = 0; ((struct ipovly *)ip)->ih_len = uh->uh_ulen; if(cksum(m, len + sizeof(struct ip))) { goto bad; } } /* * handle DHCP/BOOTP */ if (ntohs(uh->uh_dport) == BOOTP_SERVER && (ip->ip_dst.s_addr == slirp->vhost_addr.s_addr || ip->ip_dst.s_addr == 0xffffffff)) { bootp_input(m); goto bad; } /* * handle TFTP */ if (ntohs(uh->uh_dport) == TFTP_SERVER && ip->ip_dst.s_addr == slirp->vhost_addr.s_addr) { tftp_input(m); goto bad; } if (slirp->restricted) { goto bad; } /* * Locate pcb for datagram. */ so = slirp->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 = slirp->udb.so_next; tmp != &slirp->udb; tmp = tmp->so_next) { if (tmp->so_lport == uh->uh_sport && tmp->so_laddr.s_addr == ip->ip_src.s_addr) { so = tmp; break; } } if (tmp == &slirp->udb) { so = NULL; } else { slirp->udp_last_so = so; } } if (so == NULL) { /* * If there's no socket for this packet, * create one */ so = socreate(slirp); if (!so) { 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 */ so->so_laddr = ip->ip_src; so->so_lport = uh->uh_sport; 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. */ } so->so_faddr = ip->ip_dst; /* XXX */ so->so_fport = uh->uh_dport; /* XXX */ iphlen += sizeof(struct udphdr); m->m_len -= iphlen; m->m_data += iphlen; /* * Now we sendto() the packet. */ 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_free(m); } 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 *); memset(&ui->ui_i.ih_mbuf, 0 , sizeof(struct mbuf_ptr)); ui->ui_x1 = 0; ui->ui_pr = IPPROTO_UDP; ui->ui_len = htons(m->m_len - sizeof(struct ip)); /* 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 ((ui->ui_sum = cksum(m, m->m_len)) == 0) ui->ui_sum = 0xffff; ((struct ip *)ui)->ip_len = m->m_len; ((struct ip *)ui)->ip_ttl = IPDEFTTL; ((struct ip *)ui)->ip_tos = iptos; error = ip_output(so, m); return (error); } int udp_output(struct socket *so, struct mbuf *m, struct sockaddr_in *addr) { Slirp *slirp = so->slirp; struct sockaddr_in saddr, daddr; saddr = *addr; if ((so->so_faddr.s_addr & slirp->vnetwork_mask.s_addr) == slirp->vnetwork_addr.s_addr) { uint32_t inv_mask = ~slirp->vnetwork_mask.s_addr; if ((so->so_faddr.s_addr & inv_mask) == inv_mask) { saddr.sin_addr = slirp->vhost_addr; } else if (addr->sin_addr.s_addr == loopback_addr.s_addr || so->so_faddr.s_addr != slirp->vhost_addr.s_addr) { saddr.sin_addr = so->so_faddr; } } 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(struct socket *so) { if((so->s = qemu_socket(AF_INET,SOCK_DGRAM,0)) != -1) { so->so_expire = curtime + SO_EXPIRE; insque(so, &so->slirp->udb); } return(so->s); } void udp_detach(struct socket *so) { closesocket(so->s); sofree(so); } static const struct tos_t udptos[] = { {0, 53, IPTOS_LOWDELAY, 0}, /* DNS */ {0, 0, 0, 0} }; static uint8_t udp_tos(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; } struct socket * udp_listen(Slirp *slirp, uint32_t haddr, u_int hport, uint32_t laddr, u_int lport, int flags) { struct sockaddr_in addr; struct socket *so; socklen_t addrlen = sizeof(struct sockaddr_in), opt = 1; so = socreate(slirp); if (!so) { return NULL; } so->s = qemu_socket(AF_INET,SOCK_DGRAM,0); so->so_expire = curtime + SO_EXPIRE; insque(so, &slirp->udb); addr.sin_family = AF_INET; addr.sin_addr.s_addr = haddr; addr.sin_port = hport; if (bind(so->s,(struct sockaddr *)&addr, addrlen) < 0) { udp_detach(so); return NULL; } qemu_setsockopt(so->s, SOL_SOCKET, SO_REUSEADDR, &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 = slirp->vhost_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_PERSISTENT_MASK; so->so_state |= SS_ISFCONNECTED | flags; return so; }