kernel.h include for lbolt

[unix-history] / usr / src / sys / kern / uipc_socket.c

/*      uipc_socket.c   4.49    82/09/04        */

#include "../h/param.h"
#include "../h/systm.h"
#include "../h/dir.h"
#include "../h/user.h"
#include "../h/proc.h"
#include "../h/file.h"
#include "../h/inode.h"
#include "../h/buf.h"
#include "../h/mbuf.h"
#include "../h/protosw.h"
#include "../h/socket.h"
#include "../h/socketvar.h"
#include "../h/stat.h"
#include "../h/ioctl.h"
#include "../net/in.h"
#include "../net/in_systm.h"
#include "../net/route.h"
#include "../h/uio.h"

/*
* Socket support routines.
*
* DEAL WITH INTERRUPT NOTIFICATION.
*/

/*
* Create a socket.
*/
socreate(aso, type, asp, asa, options)
       struct socket **aso;
       int type;
       struct sockproto *asp;
       struct sockaddr *asa;
       int options;
{
       register struct protosw *prp;
       register struct socket *so;
       struct mbuf *m;
       int pf, proto, error;

       /*
        * Use process standard protocol/protocol family if none
        * specified by address argument.
        */
       if (asp == 0) {
               pf = PF_INET;           /* should be u.u_protof */
               proto = 0;
       } else {
               pf = asp->sp_family;
               proto = asp->sp_protocol;
       }

       /*
        * If protocol specified, look for it, otherwise
        * for a protocol of the correct type in the right family.
        */
       if (proto)
               prp = pffindproto(pf, proto);
       else
               prp = pffindtype(pf, type);
       if (prp == 0)
               return (EPROTONOSUPPORT);

       /*
        * Get a socket structure.
        */
       m = m_getclr(M_WAIT);
       if (m == 0)
               return (ENOBUFS);
       so = mtod(m, struct socket *);
       so->so_options = options;
       if (options & SO_ACCEPTCONN) {
               so->so_q = so;
               so->so_q0 = so;
               so->so_qlimit = (so->so_options & SO_NEWFDONCONN) ? 5 : 1;
       }
       so->so_state = 0;
       if (u.u_uid == 0)
               so->so_state = SS_PRIV;

       /*
        * Attach protocol to socket, initializing
        * and reserving resources.
        */
       so->so_proto = prp;
       error = (*prp->pr_usrreq)(so, PRU_ATTACH, 0, asa);
       if (error) {
               so->so_state |= SS_NOFDREF;
               sofree(so);
               return (error);
       }
       *aso = so;
       return (0);
}

sofree(so)
       struct socket *so;
{

       if (so->so_head) {
               if (!soqremque(so, 0) && !soqremque(so, 1))
                       panic("sofree dq");
               so->so_head = 0;
       }
       if (so->so_pcb || (so->so_state & SS_NOFDREF) == 0)
               return;
       sbrelease(&so->so_snd);
       sbrelease(&so->so_rcv);
       (void) m_free(dtom(so));
}

/*
* Close a socket on last file table reference removal.
* Initiate disconnect if connected.
* Free socket when disconnect complete.
*/
soclose(so, exiting)
       register struct socket *so;
       int exiting;
{
       int s = splnet();               /* conservative */

       if (so->so_options & SO_ACCEPTCONN) {
               while (so->so_q0 != so)
                       soclose(so->so_q0, 1);
               while (so->so_q != so)
                       soclose(so->so_q, 1);
       }
       if (so->so_pcb == 0)
               goto discard;
       if (exiting)
               so->so_options |= SO_KEEPALIVE;
       if (so->so_state & SS_ISCONNECTED) {
               if ((so->so_state & SS_ISDISCONNECTING) == 0) {
                       u.u_error = sodisconnect(so, (struct sockaddr *)0);
                       if (u.u_error) {
                               if (exiting)
                                       goto drop;
                               splx(s);
                               return;
                       }
               }
               if ((so->so_options & SO_DONTLINGER) == 0) {
                       if ((so->so_state & SS_ISDISCONNECTING) &&
                           (so->so_state & SS_NBIO) &&
                           exiting == 0) {
                               u.u_error = EINPROGRESS;
                               splx(s);
                               return;
                       }
                       /* should use tsleep here, for at most linger */
                       while (so->so_state & SS_ISCONNECTED)
                               sleep((caddr_t)&so->so_timeo, PZERO+1);
               }
       }
drop:
       if (so->so_pcb) {
               u.u_error = (*so->so_proto->pr_usrreq)(so, PRU_DETACH, 0, 0);
               if (exiting == 0 && u.u_error) {
                       splx(s);
                       return;
               }
       }
discard:
       so->so_state |= SS_NOFDREF;
       sofree(so);
       splx(s);
}

/*ARGSUSED*/
sostat(so, sb)
       struct socket *so;
       struct stat *sb;
{

       bzero((caddr_t)sb, sizeof (*sb));               /* XXX */
       return (0);                                     /* XXX */
}

/*
* Accept connection on a socket.
*/
soaccept(so, asa)
       struct socket *so;
       struct sockaddr *asa;
{
       int s = splnet();
       int error;

       error = (*so->so_proto->pr_usrreq)(so, PRU_ACCEPT, 0, (caddr_t)asa);
       splx(s);
       return (error);
}

/*
* Connect socket to a specified address.
* If already connected or connecting, then avoid
* the protocol entry, to keep its job simpler.
*/
soconnect(so, asa)
       struct socket *so;
       struct sockaddr *asa;
{
       int s = splnet();
       int error;

       if (so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) {
               error = EISCONN;
               goto bad;
       }
       error = (*so->so_proto->pr_usrreq)(so, PRU_CONNECT, 0, (caddr_t)asa);
bad:
       splx(s);
       return (error);
}

/*
* Disconnect from a socket.
* Address parameter is from system call for later multicast
* protocols.  Check to make sure that connected and no disconnect
* in progress (for protocol's sake), and then invoke protocol.
*/
sodisconnect(so, asa)
       struct socket *so;
       struct sockaddr *asa;
{
       int s = splnet();
       int error;

       if ((so->so_state & SS_ISCONNECTED) == 0) {
               error = ENOTCONN;
               goto bad;
       }
       if (so->so_state & SS_ISDISCONNECTING) {
               error = EALREADY;
               goto bad;
       }
       error = (*so->so_proto->pr_usrreq)(so, PRU_DISCONNECT, 0, asa);
bad:
       splx(s);
       return (error);
}

/*
* Send on a socket.
* If send must go all at once and message is larger than
* send buffering, then hard error.
* Lock against other senders.
* If must go all at once and not enough room now, then
* inform user that this would block and do nothing.
*/
sosend(so, asa, uio)
       register struct socket *so;
       struct sockaddr *asa;
       struct uio *uio;
{
       struct mbuf *top = 0;
       register struct mbuf *m, **mp = ⊤
       register u_int len;
       int error = 0, space, s;

       if (sosendallatonce(so) && uio->uio_resid > so->so_snd.sb_hiwat)
               return (EMSGSIZE);
#ifdef notdef
       /* NEED TO PREVENT BUSY WAITING IN SELECT FOR WRITING */
       if ((so->so_snd.sb_flags & SB_LOCK) && (so->so_state & SS_NBIO))
               return (EWOULDBLOCK);
#endif
restart:
       sblock(&so->so_snd);
#define snderr(errno)   { error = errno; splx(s); goto release; }

       u.u_ru.ru_msgsnd++;
again:
       s = splnet();
       if (so->so_state & SS_CANTSENDMORE) {
               psignal(u.u_procp, SIGPIPE);
               snderr(EPIPE);
       }
       if (so->so_error) {
               error = so->so_error;
               so->so_error = 0;                               /* ??? */
               splx(s);
               goto release;
       }
       if ((so->so_state & SS_ISCONNECTED) == 0) {
               if (so->so_proto->pr_flags & PR_CONNREQUIRED)
                       snderr(ENOTCONN);
               if (asa == 0)
                       snderr(EDESTADDRREQ);
       }
       if (top) {
               error = (*so->so_proto->pr_usrreq)(so, PRU_SEND, top, asa);
               top = 0;
               if (error) {
                       splx(s);
                       goto release;
               }
               mp = ⊤
       }
       if (uio->uio_resid == 0) {
               splx(s);
               goto release;
       }
       space = sbspace(&so->so_snd);
       if (space <= 0 || sosendallatonce(so) && space < uio->uio_resid) {
               if (so->so_state & SS_NBIO)
                       snderr(EWOULDBLOCK);
               sbunlock(&so->so_snd);
               sbwait(&so->so_snd);
               splx(s);
               goto restart;
       }
       splx(s);
       while (uio->uio_resid > 0 && space > 0) {
               register struct iovec *iov = uio->uio_iov;

               if (iov->iov_len == 0) {
                       uio->uio_iov++;
                       uio->uio_iovcnt--;
                       if (uio->uio_iovcnt < 0)
                               panic("sosend");
                       continue;
               }
               MGET(m, 1);
               if (m == NULL) {
                       error = ENOBUFS;                        /* SIGPIPE? */
                       goto release;
               }
               if (iov->iov_len >= CLBYTES && space >= CLBYTES) {
                       register struct mbuf *p;
                       MCLGET(p, 1);
                       if (p == 0)
                               goto nopages;
                       m->m_off = (int)p - (int)m;
                       len = CLBYTES;
               } else {
nopages:
                       m->m_off = MMINOFF;
                       len = MIN(MLEN, iov->iov_len);
               }
               uiomove(mtod(m, caddr_t), len, UIO_WRITE, uio);
               m->m_len = len;
               *mp = m;
               mp = &m->m_next;
               space = sbspace(&so->so_snd);
       }
       goto again;

release:
       sbunlock(&so->so_snd);
       if (top)
               m_freem(top);
       return (error);
}

soreceive(so, asa, uio)
       register struct socket *so;
       struct sockaddr *asa;
       struct uio *uio;
{
       register struct iovec *iov;
       register struct mbuf *m, *n;
       u_int len;
       int eor, s, error = 0;

restart:
       sblock(&so->so_rcv);
       s = splnet();

#define rcverr(errno)   { error = errno; splx(s); goto release; }
       if (so->so_rcv.sb_cc == 0) {
               if (so->so_error) {
                       error = so->so_error;
                       so->so_error = 0;
                       splx(s);
                       goto release;
               }
               if (so->so_state & SS_CANTRCVMORE) {
                       splx(s);
                       goto release;
               }
               if ((so->so_state & SS_ISCONNECTED) == 0 &&
                   (so->so_proto->pr_flags & PR_CONNREQUIRED))
                       rcverr(ENOTCONN);
               if (so->so_state & SS_NBIO)
                       rcverr(EWOULDBLOCK);
               sbunlock(&so->so_rcv);
               sbwait(&so->so_rcv);
               splx(s);
               goto restart;
       }
       u.u_ru.ru_msgrcv++;
       m = so->so_rcv.sb_mb;
       if (m == 0)
               panic("receive");
       if (so->so_proto->pr_flags & PR_ADDR) {
               if (m->m_len != sizeof (struct sockaddr))
                       panic("soreceive addr");
               if (asa)
                       bcopy(mtod(m, caddr_t), (caddr_t)asa, sizeof (*asa));
               so->so_rcv.sb_cc -= m->m_len;
               so->so_rcv.sb_mbcnt -= MSIZE;
               m = m_free(m);
               if (m == 0)
                       panic("receive 2");
               so->so_rcv.sb_mb = m;
       }
       eor = 0;
       do {
               if (uio->uio_resid <= 0)
                       break;
               len = uio->uio_resid;
               so->so_state &= ~SS_RCVATMARK;
               if (so->so_oobmark && len > so->so_oobmark)
                       len = so->so_oobmark;
               if (len > m->m_len)
                       len = m->m_len;
               splx(s);
               uiomove(mtod(m, caddr_t), (int)len, UIO_READ, uio);
               s = splnet();
               if (len == m->m_len) {
                       eor = (int)m->m_act;
                       sbfree(&so->so_rcv, m);
                       so->so_rcv.sb_mb = m->m_next;
                       MFREE(m, n);
               } else {
                       m->m_off += len;
                       m->m_len -= len;
                       so->so_rcv.sb_cc -= len;
               }
               if (so->so_oobmark) {
                       so->so_oobmark -= len;
                       if (so->so_oobmark == 0) {
                               so->so_state |= SS_RCVATMARK;
                               break;
                       }
               }
       } while ((m = so->so_rcv.sb_mb) && !eor);
       if ((so->so_proto->pr_flags & PR_ATOMIC) && eor == 0)
               do {
                       if (m == 0)
                               panic("receive 3");
                       sbfree(&so->so_rcv, m);
                       eor = (int)m->m_act;
                       so->so_rcv.sb_mb = m->m_next;
                       MFREE(m, n);
                       m = n;
               } while (eor == 0);
       if ((so->so_proto->pr_flags & PR_WANTRCVD) && so->so_pcb)
               (*so->so_proto->pr_usrreq)(so, PRU_RCVD, 0, 0);
release:
       sbunlock(&so->so_rcv);
       splx(s);
       return (error);
}

sohasoutofband(so)
       struct socket *so;
{

       if (so->so_pgrp == 0)
               return;
       if (so->so_pgrp > 0)
               gsignal(so->so_pgrp, SIGURG);
       else {
               struct proc *p = pfind(-so->so_pgrp);

               if (p)
                       psignal(p, SIGURG);
       }
}

/*ARGSUSED*/
soioctl(so, cmd, data)
       register struct socket *so;
       int cmd;
       register char *data;
{

       switch (cmd) {

       case FIONBIO:
               if (*(int *)data)
                       so->so_state |= SS_NBIO;
               else
                       so->so_state &= ~SS_NBIO;
               return;

       case FIOASYNC:
               if (*(int *)data)
                       so->so_state |= SS_ASYNC;
               else
                       so->so_state &= ~SS_ASYNC;
               return;

       case SIOCSKEEP:
               if (*(int *)data)
                       so->so_options &= ~SO_KEEPALIVE;
               else
                       so->so_options |= SO_KEEPALIVE;
               return;

       case SIOCGKEEP:
               *(int *)data = (so->so_options & SO_KEEPALIVE) != 0;
               return;

       case SIOCSLINGER:
               so->so_linger = *(int *)data;
               if (so->so_linger)
                       so->so_options &= ~SO_DONTLINGER;
               else
                       so->so_options |= SO_DONTLINGER;
               return;

       case SIOCGLINGER:
               *(int *)data = so->so_linger;
               return;

       case SIOCSPGRP:
               so->so_pgrp = *(int *)data;
               return;

       case SIOCGPGRP:
               *(int *)data = so->so_pgrp;
               return;

       case SIOCDONE: {
               int flags = *(int *)data;

               flags++;
               if (flags & FREAD) {
                       int s = splimp();
                       socantrcvmore(so);
                       sbflush(&so->so_rcv);
                       splx(s);
               }
               if (flags & FWRITE)
                       u.u_error = (*so->so_proto->pr_usrreq)(so, PRU_SHUTDOWN, (struct mbuf *)0, 0);
               return;
       }

       case SIOCSENDOOB: {
               char oob = *(char *)data;
               struct mbuf *m;

               m = m_get(M_DONTWAIT);
               if (m == 0) {
                       u.u_error = ENOBUFS;
                       return;
               }
               m->m_off = MMINOFF;
               m->m_len = sizeof (char);
               *mtod(m, char *) = oob;
               (*so->so_proto->pr_usrreq)(so, PRU_SENDOOB, m, 0);
               return;
       }

       case SIOCRCVOOB: {
               struct mbuf *m = m_get(M_DONTWAIT);

               if (m == 0) {
                       u.u_error = ENOBUFS;
                       return;
               }
               m->m_off = MMINOFF; *mtod(m, caddr_t) = 0;
               (*so->so_proto->pr_usrreq)(so, PRU_RCVOOB, m, 0);
               *(char *)data = *mtod(m, char *);
               (void) m_free(m);
               return;
       }

       case SIOCATMARK:
               *(int *)data = (so->so_state&SS_RCVATMARK) != 0;
               return;

       /* routing table update calls */
       case SIOCADDRT:
       case SIOCDELRT:
               if (!suser())
                       return;
               u.u_error = rtrequest(cmd, (struct rtentry *)data);
               return;

       /* type/protocol specific ioctls */
       }
       u.u_error = EOPNOTSUPP;
}