Archipelago » qemu

/*

 * 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;

}

/* 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);

        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 *);

    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;

        }

        setsockopt(so->s,SOL_SOCKET,SO_REUSEADDR,(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 = 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;

}