Archipelago » qemu

/*

 * Copyright (c) 1995 Danny Gasparovski.

 *

 * Please read the file COPYRIGHT for the

 * terms and conditions of the copyright.

 */

#include "qemu-common.h"

#include <slirp.h>

#include "ip_icmp.h"

#ifdef __sun__

#include <sys/filio.h>

#endif

static void sofcantrcvmore(struct socket *so);

static void sofcantsendmore(struct socket *so);

struct socket *

solookup(struct socket *head, struct in_addr laddr, u_int lport,

         struct in_addr faddr, u_int fport)

{

        struct socket *so;

        for (so = head->so_next; so != head; so = so->so_next) {

                if (so->so_lport == lport &&

                    so->so_laddr.s_addr == laddr.s_addr &&

                    so->so_faddr.s_addr == faddr.s_addr &&

                    so->so_fport == fport)

                   break;

        }

        if (so == head)

           return (struct socket *)NULL;

        return so;

}

/*

 * Create a new socket, initialise the fields

 * It is the responsibility of the caller to

 * insque() it into the correct linked-list

 */

struct socket *

socreate(Slirp *slirp)

{

  struct socket *so;

  so = (struct socket *)malloc(sizeof(struct socket));

  if(so) {

    memset(so, 0, sizeof(struct socket));

    so->so_state = SS_NOFDREF;

    so->s = -1;

    so->slirp = slirp;

  }

  return(so);

}

/*

 * remque and free a socket, clobber cache

 */

void

sofree(struct socket *so)

{

  Slirp *slirp = so->slirp;

  if (so->so_emu==EMU_RSH && so->extra) {

        sofree(so->extra);

        so->extra=NULL;

  }

  if (so == slirp->tcp_last_so) {

      slirp->tcp_last_so = &slirp->tcb;

  } else if (so == slirp->udp_last_so) {

      slirp->udp_last_so = &slirp->udb;

  } else if (so == slirp->icmp_last_so) {

      slirp->icmp_last_so = &slirp->icmp;

  }

  m_free(so->so_m);

  if(so->so_next && so->so_prev)

    remque(so);  /* crashes if so is not in a queue */

  free(so);

}

size_t sopreprbuf(struct socket *so, struct iovec *iov, int *np)

{

        int n, lss, total;

        struct sbuf *sb = &so->so_snd;

        int len = sb->sb_datalen - sb->sb_cc;

        int mss = so->so_tcpcb->t_maxseg;

        DEBUG_CALL("sopreprbuf");

        DEBUG_ARG("so = %lx", (long )so);

        if (len <= 0)

                return 0;

        iov[0].iov_base = sb->sb_wptr;

        iov[1].iov_base = NULL;

        iov[1].iov_len = 0;

        if (sb->sb_wptr < sb->sb_rptr) {

                iov[0].iov_len = sb->sb_rptr - sb->sb_wptr;

                /* Should never succeed, but... */

                if (iov[0].iov_len > len)

                   iov[0].iov_len = len;

                if (iov[0].iov_len > mss)

                   iov[0].iov_len -= iov[0].iov_len%mss;

                n = 1;

        } else {

                iov[0].iov_len = (sb->sb_data + sb->sb_datalen) - sb->sb_wptr;

                /* Should never succeed, but... */

                if (iov[0].iov_len > len) iov[0].iov_len = len;

                len -= iov[0].iov_len;

                if (len) {

                        iov[1].iov_base = sb->sb_data;

                        iov[1].iov_len = sb->sb_rptr - sb->sb_data;

                        if(iov[1].iov_len > len)

                           iov[1].iov_len = len;

                        total = iov[0].iov_len + iov[1].iov_len;

                        if (total > mss) {

                                lss = total%mss;

                                if (iov[1].iov_len > lss) {

                                        iov[1].iov_len -= lss;

                                        n = 2;

                                } else {

                                        lss -= iov[1].iov_len;

                                        iov[0].iov_len -= lss;

                                        n = 1;

                                }

                        } else

                                n = 2;

                } else {

                        if (iov[0].iov_len > mss)

                           iov[0].iov_len -= iov[0].iov_len%mss;

                        n = 1;

                }

        }

        if (np)

                *np = n;

        return iov[0].iov_len + (n - 1) * iov[1].iov_len;

}

/*

 * Read from so's socket into sb_snd, updating all relevant sbuf fields

 * NOTE: This will only be called if it is select()ed for reading, so

 * a read() of 0 (or less) means it's disconnected

 */

int

soread(struct socket *so)

{

        int n, nn;

        struct sbuf *sb = &so->so_snd;

        struct iovec iov[2];

        DEBUG_CALL("soread");

        DEBUG_ARG("so = %lx", (long )so);

        /*

         * No need to check if there's enough room to read.

         * soread wouldn't have been called if there weren't

         */

        sopreprbuf(so, iov, &n);

#ifdef HAVE_READV

        nn = readv(so->s, (struct iovec *)iov, n);

        DEBUG_MISC((dfd, " ... read nn = %d bytes\n", nn));

#else

        nn = qemu_recv(so->s, iov[0].iov_base, iov[0].iov_len,0);

#endif

        if (nn <= 0) {

                if (nn < 0 && (errno == EINTR || errno == EAGAIN))

                        return 0;

                else {

                        DEBUG_MISC((dfd, " --- soread() disconnected, nn = %d, errno = %d-%s\n", nn, errno,strerror(errno)));

                        sofcantrcvmore(so);

                        tcp_sockclosed(sototcpcb(so));

                        return -1;

                }

        }

#ifndef HAVE_READV

        /*

         * If there was no error, try and read the second time round

         * We read again if n = 2 (ie, there's another part of the buffer)

         * and we read as much as we could in the first read

         * We don't test for <= 0 this time, because there legitimately

         * might not be any more data (since the socket is non-blocking),

         * a close will be detected on next iteration.

         * A return of -1 wont (shouldn't) happen, since it didn't happen above

         */

        if (n == 2 && nn == iov[0].iov_len) {

            int ret;

            ret = qemu_recv(so->s, iov[1].iov_base, iov[1].iov_len,0);

            if (ret > 0)

                nn += ret;

        }

        DEBUG_MISC((dfd, " ... read nn = %d bytes\n", nn));

#endif

        /* Update fields */

        sb->sb_cc += nn;

        sb->sb_wptr += nn;

        if (sb->sb_wptr >= (sb->sb_data + sb->sb_datalen))

                sb->sb_wptr -= sb->sb_datalen;

        return nn;

}

int soreadbuf(struct socket *so, const char *buf, int size)

{

    int n, nn, copy = size;

        struct sbuf *sb = &so->so_snd;

        struct iovec iov[2];

        DEBUG_CALL("soreadbuf");

        DEBUG_ARG("so = %lx", (long )so);

        /*

         * No need to check if there's enough room to read.

         * soread wouldn't have been called if there weren't

         */

        if (sopreprbuf(so, iov, &n) < size)

        goto err;

    nn = MIN(iov[0].iov_len, copy);

    memcpy(iov[0].iov_base, buf, nn);

    copy -= nn;

    buf += nn;

    if (copy == 0)

        goto done;

    memcpy(iov[1].iov_base, buf, copy);

done:

    /* Update fields */

        sb->sb_cc += size;

        sb->sb_wptr += size;

        if (sb->sb_wptr >= (sb->sb_data + sb->sb_datalen))

                sb->sb_wptr -= sb->sb_datalen;

    return size;

err:

    sofcantrcvmore(so);

    tcp_sockclosed(sototcpcb(so));

    fprintf(stderr, "soreadbuf buffer to small");

    return -1;

}

/*

 * Get urgent data

 *

 * When the socket is created, we set it SO_OOBINLINE,

 * so when OOB data arrives, we soread() it and everything

 * in the send buffer is sent as urgent data

 */

void

sorecvoob(struct socket *so)

{

        struct tcpcb *tp = sototcpcb(so);

        DEBUG_CALL("sorecvoob");

        DEBUG_ARG("so = %lx", (long)so);

        /*

         * We take a guess at how much urgent data has arrived.

         * In most situations, when urgent data arrives, the next

         * read() should get all the urgent data.  This guess will

         * be wrong however if more data arrives just after the

         * urgent data, or the read() doesn't return all the

         * urgent data.

         */

        soread(so);

        tp->snd_up = tp->snd_una + so->so_snd.sb_cc;

        tp->t_force = 1;

        tcp_output(tp);

        tp->t_force = 0;

}

/*

 * Send urgent data

 * There's a lot duplicated code here, but...

 */

int

sosendoob(struct socket *so)

{

        struct sbuf *sb = &so->so_rcv;

        char buff[2048]; /* XXX Shouldn't be sending more oob data than this */

        int n, len;

        DEBUG_CALL("sosendoob");

        DEBUG_ARG("so = %lx", (long)so);

        DEBUG_ARG("sb->sb_cc = %d", sb->sb_cc);

        if (so->so_urgc > 2048)

           so->so_urgc = 2048; /* XXXX */

        if (sb->sb_rptr < sb->sb_wptr) {

                /* We can send it directly */

                n = slirp_send(so, sb->sb_rptr, so->so_urgc, (MSG_OOB)); /* |MSG_DONTWAIT)); */

                so->so_urgc -= n;

                DEBUG_MISC((dfd, " --- sent %d bytes urgent data, %d urgent bytes left\n", n, so->so_urgc));

        } else {

                /*

                 * Since there's no sendv or sendtov like writev,

                 * we must copy all data to a linear buffer then

                 * send it all

                 */

                len = (sb->sb_data + sb->sb_datalen) - sb->sb_rptr;

                if (len > so->so_urgc) len = so->so_urgc;

                memcpy(buff, sb->sb_rptr, len);

                so->so_urgc -= len;

                if (so->so_urgc) {

                        n = sb->sb_wptr - sb->sb_data;

                        if (n > so->so_urgc) n = so->so_urgc;

                        memcpy((buff + len), sb->sb_data, n);

                        so->so_urgc -= n;

                        len += n;

                }

                n = slirp_send(so, buff, len, (MSG_OOB)); /* |MSG_DONTWAIT)); */

#ifdef DEBUG

                if (n != len)

                   DEBUG_ERROR((dfd, "Didn't send all data urgently XXXXX\n"));

#endif

                DEBUG_MISC((dfd, " ---2 sent %d bytes urgent data, %d urgent bytes left\n", n, so->so_urgc));

        }

        sb->sb_cc -= n;

        sb->sb_rptr += n;

        if (sb->sb_rptr >= (sb->sb_data + sb->sb_datalen))

                sb->sb_rptr -= sb->sb_datalen;

        return n;

}

/*

 * Write data from so_rcv to so's socket,

 * updating all sbuf field as necessary

 */

int

sowrite(struct socket *so)

{

        int  n,nn;

        struct sbuf *sb = &so->so_rcv;

        int len = sb->sb_cc;

        struct iovec iov[2];

        DEBUG_CALL("sowrite");

        DEBUG_ARG("so = %lx", (long)so);

        if (so->so_urgc) {

                sosendoob(so);

                if (sb->sb_cc == 0)

                        return 0;

        }

        /*

         * No need to check if there's something to write,

         * sowrite wouldn't have been called otherwise

         */

        iov[0].iov_base = sb->sb_rptr;

        iov[1].iov_base = NULL;

        iov[1].iov_len = 0;

        if (sb->sb_rptr < sb->sb_wptr) {

                iov[0].iov_len = sb->sb_wptr - sb->sb_rptr;

                /* Should never succeed, but... */

                if (iov[0].iov_len > len) iov[0].iov_len = len;

                n = 1;

        } else {

                iov[0].iov_len = (sb->sb_data + sb->sb_datalen) - sb->sb_rptr;

                if (iov[0].iov_len > len) iov[0].iov_len = len;

                len -= iov[0].iov_len;

                if (len) {

                        iov[1].iov_base = sb->sb_data;

                        iov[1].iov_len = sb->sb_wptr - sb->sb_data;

                        if (iov[1].iov_len > len) iov[1].iov_len = len;

                        n = 2;

                } else

                        n = 1;

        }

        /* Check if there's urgent data to send, and if so, send it */

#ifdef HAVE_READV

        nn = writev(so->s, (const struct iovec *)iov, n);

        DEBUG_MISC((dfd, "  ... wrote nn = %d bytes\n", nn));

#else

        nn = slirp_send(so, iov[0].iov_base, iov[0].iov_len,0);

#endif

        /* This should never happen, but people tell me it does *shrug* */

        if (nn < 0 && (errno == EAGAIN || errno == EINTR))

                return 0;

        if (nn <= 0) {

                DEBUG_MISC((dfd, " --- sowrite disconnected, so->so_state = %x, errno = %d\n",

                        so->so_state, errno));

                sofcantsendmore(so);

                tcp_sockclosed(sototcpcb(so));

                return -1;

        }

#ifndef HAVE_READV

        if (n == 2 && nn == iov[0].iov_len) {

            int ret;

            ret = slirp_send(so, iov[1].iov_base, iov[1].iov_len,0);

            if (ret > 0)

                nn += ret;

        }

        DEBUG_MISC((dfd, "  ... wrote nn = %d bytes\n", nn));

#endif

        /* Update sbuf */

        sb->sb_cc -= nn;

        sb->sb_rptr += nn;

        if (sb->sb_rptr >= (sb->sb_data + sb->sb_datalen))

                sb->sb_rptr -= sb->sb_datalen;

        /*

         * If in DRAIN mode, and there's no more data, set

         * it CANTSENDMORE

         */

        if ((so->so_state & SS_FWDRAIN) && sb->sb_cc == 0)

                sofcantsendmore(so);

        return nn;

}

/*

 * 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 */

}

/*

 * sendto() a socket

 */

int

sosendto(struct socket *so, struct mbuf *m)

{

        Slirp *slirp = so->slirp;

        int ret;

        struct sockaddr_in addr;

        DEBUG_CALL("sosendto");

        DEBUG_ARG("so = %lx", (long)so);

        DEBUG_ARG("m = %lx", (long)m);

        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;

        DEBUG_MISC((dfd, " sendto()ing, addr.sin_port=%d, addr.sin_addr.s_addr=%.16s\n", ntohs(addr.sin_port), inet_ntoa(addr.sin_addr)));

        /* Don't care what port we get */

        ret = sendto(so->s, m->m_data, m->m_len, 0,

                     (struct sockaddr *)&addr, sizeof (struct sockaddr));

        if (ret < 0)

                return -1;

        /*

         * Kill the socket if there's no reply in 4 minutes,

         * but only if it's an expirable socket

         */

        if (so->so_expire)

                so->so_expire = curtime + SO_EXPIRE;

        so->so_state &= SS_PERSISTENT_MASK;

        so->so_state |= SS_ISFCONNECTED; /* So that it gets select()ed */

        return 0;

}

/*

 * Listen for incoming TCP connections

 */

struct socket *

tcp_listen(Slirp *slirp, uint32_t haddr, u_int hport, uint32_t laddr,

           u_int lport, int flags)

{

        struct sockaddr_in addr;

        struct socket *so;

        int s, opt = 1;

        socklen_t addrlen = sizeof(addr);

        memset(&addr, 0, addrlen);

        DEBUG_CALL("tcp_listen");

        DEBUG_ARG("haddr = %x", haddr);

        DEBUG_ARG("hport = %d", hport);

        DEBUG_ARG("laddr = %x", laddr);

        DEBUG_ARG("lport = %d", lport);

        DEBUG_ARG("flags = %x", flags);

        so = socreate(slirp);

        if (!so) {

          return NULL;

        }

        /* Don't tcp_attach... we don't need so_snd nor so_rcv */

        if ((so->so_tcpcb = tcp_newtcpcb(so)) == NULL) {

                free(so);

                return NULL;

        }

        insque(so, &slirp->tcb);

        /*

         * SS_FACCEPTONCE sockets must time out.

         */

        if (flags & SS_FACCEPTONCE)

           so->so_tcpcb->t_timer[TCPT_KEEP] = TCPTV_KEEP_INIT*2;

        so->so_state &= SS_PERSISTENT_MASK;

        so->so_state |= (SS_FACCEPTCONN | flags);

        so->so_lport = lport; /* Kept in network format */

        so->so_laddr.s_addr = laddr; /* Ditto */

        addr.sin_family = AF_INET;

        addr.sin_addr.s_addr = haddr;

        addr.sin_port = hport;

        if (((s = qemu_socket(AF_INET,SOCK_STREAM,0)) < 0) ||

            (setsockopt(s,SOL_SOCKET,SO_REUSEADDR,(char *)&opt,sizeof(int)) < 0) ||

            (bind(s,(struct sockaddr *)&addr, sizeof(addr)) < 0) ||

            (listen(s,1) < 0)) {

                int tmperrno = errno; /* Don't clobber the real reason we failed */

                close(s);

                sofree(so);

                /* Restore the real errno */

#ifdef _WIN32

                WSASetLastError(tmperrno);

#else

                errno = tmperrno;

#endif

                return NULL;

        }

        setsockopt(s,SOL_SOCKET,SO_OOBINLINE,(char *)&opt,sizeof(int));

        getsockname(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->s = s;

        return so;

}

/*

 * Various session state calls

 * XXX Should be #define's

 * The socket state stuff needs work, these often get call 2 or 3

 * times each when only 1 was needed

 */

void

soisfconnecting(struct socket *so)

{

        so->so_state &= ~(SS_NOFDREF|SS_ISFCONNECTED|SS_FCANTRCVMORE|

                          SS_FCANTSENDMORE|SS_FWDRAIN);

        so->so_state |= SS_ISFCONNECTING; /* Clobber other states */

}

void

soisfconnected(struct socket *so)

{

        so->so_state &= ~(SS_ISFCONNECTING|SS_FWDRAIN|SS_NOFDREF);

        so->so_state |= SS_ISFCONNECTED; /* Clobber other states */

}

static void

sofcantrcvmore(struct socket *so)

{

        if ((so->so_state & SS_NOFDREF) == 0) {

                shutdown(so->s,0);

                if(global_writefds) {

                  FD_CLR(so->s,global_writefds);

                }

        }

        so->so_state &= ~(SS_ISFCONNECTING);

        if (so->so_state & SS_FCANTSENDMORE) {

           so->so_state &= SS_PERSISTENT_MASK;

           so->so_state |= SS_NOFDREF; /* Don't select it */

        } else {

           so->so_state |= SS_FCANTRCVMORE;

        }

}

static void

sofcantsendmore(struct socket *so)

{

        if ((so->so_state & SS_NOFDREF) == 0) {

            shutdown(so->s,1);           /* send FIN to fhost */

            if (global_readfds) {

                FD_CLR(so->s,global_readfds);

            }

            if (global_xfds) {

                FD_CLR(so->s,global_xfds);

            }

        }

        so->so_state &= ~(SS_ISFCONNECTING);

        if (so->so_state & SS_FCANTRCVMORE) {

           so->so_state &= SS_PERSISTENT_MASK;

           so->so_state |= SS_NOFDREF; /* as above */

        } else {

           so->so_state |= SS_FCANTSENDMORE;

        }

}

/*

 * Set write drain mode

 * Set CANTSENDMORE once all data has been write()n

 */

void

sofwdrain(struct socket *so)

{

        if (so->so_rcv.sb_cc)

                so->so_state |= SS_FWDRAIN;

        else

                sofcantsendmore(so);

}