freebsd-skq/sys/kern/uipc_socket2.c
rwatson d53af1ffe2 Change two XXX's to two notes: the fact that SOCK_LOCK(so) ==
SOCKBUF_LOCK(&so->so_rcv) is encoded, which is worth noting, but not a
bug.
2006-08-02 16:23:52 +00:00

398 lines
10 KiB
C

/*-
* 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.
* 4. 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.
*
* @(#)uipc_socket2.c 8.1 (Berkeley) 6/10/93
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_param.h"
#include <sys/param.h>
#include <sys/domain.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/protosw.h>
#include <sys/resourcevar.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/stat.h>
/*
* Primitive routines for operating on sockets.
*/
/*
* Procedures to manipulate state flags of socket
* and do appropriate wakeups. Normal sequence from the
* active (originating) side is that soisconnecting() is
* called during processing of connect() call,
* resulting in an eventual call to soisconnected() if/when the
* connection is established. When the connection is torn down
* soisdisconnecting() is called during processing of disconnect() call,
* and soisdisconnected() is called when the connection to the peer
* is totally severed. The semantics of these routines are such that
* connectionless protocols can call soisconnected() and soisdisconnected()
* only, bypassing the in-progress calls when setting up a ``connection''
* takes no time.
*
* From the passive side, a socket is created with
* two queues of sockets: so_incomp for connections in progress
* and so_comp for connections already made and awaiting user acceptance.
* As a protocol is preparing incoming connections, it creates a socket
* structure queued on so_incomp by calling sonewconn(). When the connection
* is established, soisconnected() is called, and transfers the
* socket structure to so_comp, making it available to accept().
*
* If a socket is closed with sockets on either
* so_incomp or so_comp, these sockets are dropped.
*
* If higher level protocols are implemented in
* the kernel, the wakeups done here will sometimes
* cause software-interrupt process scheduling.
*/
void
soisconnecting(so)
register struct socket *so;
{
SOCK_LOCK(so);
so->so_state &= ~(SS_ISCONNECTED|SS_ISDISCONNECTING);
so->so_state |= SS_ISCONNECTING;
SOCK_UNLOCK(so);
}
void
soisconnected(so)
struct socket *so;
{
struct socket *head;
ACCEPT_LOCK();
SOCK_LOCK(so);
so->so_state &= ~(SS_ISCONNECTING|SS_ISDISCONNECTING|SS_ISCONFIRMING);
so->so_state |= SS_ISCONNECTED;
head = so->so_head;
if (head != NULL && (so->so_qstate & SQ_INCOMP)) {
if ((so->so_options & SO_ACCEPTFILTER) == 0) {
SOCK_UNLOCK(so);
TAILQ_REMOVE(&head->so_incomp, so, so_list);
head->so_incqlen--;
so->so_qstate &= ~SQ_INCOMP;
TAILQ_INSERT_TAIL(&head->so_comp, so, so_list);
head->so_qlen++;
so->so_qstate |= SQ_COMP;
ACCEPT_UNLOCK();
sorwakeup(head);
wakeup_one(&head->so_timeo);
} else {
ACCEPT_UNLOCK();
so->so_upcall =
head->so_accf->so_accept_filter->accf_callback;
so->so_upcallarg = head->so_accf->so_accept_filter_arg;
so->so_rcv.sb_flags |= SB_UPCALL;
so->so_options &= ~SO_ACCEPTFILTER;
SOCK_UNLOCK(so);
so->so_upcall(so, so->so_upcallarg, M_DONTWAIT);
}
return;
}
SOCK_UNLOCK(so);
ACCEPT_UNLOCK();
wakeup(&so->so_timeo);
sorwakeup(so);
sowwakeup(so);
}
void
soisdisconnecting(so)
register struct socket *so;
{
/*
* Note: This code assumes that SOCK_LOCK(so) and
* SOCKBUF_LOCK(&so->so_rcv) are the same.
*/
SOCKBUF_LOCK(&so->so_rcv);
so->so_state &= ~SS_ISCONNECTING;
so->so_state |= SS_ISDISCONNECTING;
so->so_rcv.sb_state |= SBS_CANTRCVMORE;
sorwakeup_locked(so);
SOCKBUF_LOCK(&so->so_snd);
so->so_snd.sb_state |= SBS_CANTSENDMORE;
sowwakeup_locked(so);
wakeup(&so->so_timeo);
}
void
soisdisconnected(so)
register struct socket *so;
{
/*
* Note: This code assumes that SOCK_LOCK(so) and
* SOCKBUF_LOCK(&so->so_rcv) are the same.
*/
SOCKBUF_LOCK(&so->so_rcv);
so->so_state &= ~(SS_ISCONNECTING|SS_ISCONNECTED|SS_ISDISCONNECTING);
so->so_state |= SS_ISDISCONNECTED;
so->so_rcv.sb_state |= SBS_CANTRCVMORE;
sorwakeup_locked(so);
SOCKBUF_LOCK(&so->so_snd);
so->so_snd.sb_state |= SBS_CANTSENDMORE;
sbdrop_locked(&so->so_snd, so->so_snd.sb_cc);
sowwakeup_locked(so);
wakeup(&so->so_timeo);
}
/*
* Create a "control" mbuf containing the specified data
* with the specified type for presentation on a socket buffer.
*/
struct mbuf *
sbcreatecontrol(p, size, type, level)
caddr_t p;
register int size;
int type, level;
{
register struct cmsghdr *cp;
struct mbuf *m;
if (CMSG_SPACE((u_int)size) > MCLBYTES)
return ((struct mbuf *) NULL);
if (CMSG_SPACE((u_int)size) > MLEN)
m = m_getcl(M_DONTWAIT, MT_CONTROL, 0);
else
m = m_get(M_DONTWAIT, MT_CONTROL);
if (m == NULL)
return ((struct mbuf *) NULL);
cp = mtod(m, struct cmsghdr *);
m->m_len = 0;
KASSERT(CMSG_SPACE((u_int)size) <= M_TRAILINGSPACE(m),
("sbcreatecontrol: short mbuf"));
if (p != NULL)
(void)memcpy(CMSG_DATA(cp), p, size);
m->m_len = CMSG_SPACE(size);
cp->cmsg_len = CMSG_LEN(size);
cp->cmsg_level = level;
cp->cmsg_type = type;
return (m);
}
/*
* Some routines that return EOPNOTSUPP for entry points that are not
* supported by a protocol. Fill in as needed.
*/
int
pru_accept_notsupp(struct socket *so, struct sockaddr **nam)
{
return EOPNOTSUPP;
}
int
pru_attach_notsupp(struct socket *so, int proto, struct thread *td)
{
return EOPNOTSUPP;
}
int
pru_bind_notsupp(struct socket *so, struct sockaddr *nam, struct thread *td)
{
return EOPNOTSUPP;
}
int
pru_connect_notsupp(struct socket *so, struct sockaddr *nam, struct thread *td)
{
return EOPNOTSUPP;
}
int
pru_connect2_notsupp(struct socket *so1, struct socket *so2)
{
return EOPNOTSUPP;
}
int
pru_control_notsupp(struct socket *so, u_long cmd, caddr_t data,
struct ifnet *ifp, struct thread *td)
{
return EOPNOTSUPP;
}
int
pru_disconnect_notsupp(struct socket *so)
{
return EOPNOTSUPP;
}
int
pru_listen_notsupp(struct socket *so, int backlog, struct thread *td)
{
return EOPNOTSUPP;
}
int
pru_peeraddr_notsupp(struct socket *so, struct sockaddr **nam)
{
return EOPNOTSUPP;
}
int
pru_rcvd_notsupp(struct socket *so, int flags)
{
return EOPNOTSUPP;
}
int
pru_rcvoob_notsupp(struct socket *so, struct mbuf *m, int flags)
{
return EOPNOTSUPP;
}
int
pru_send_notsupp(struct socket *so, int flags, struct mbuf *m,
struct sockaddr *addr, struct mbuf *control, struct thread *td)
{
return EOPNOTSUPP;
}
/*
* This isn't really a ``null'' operation, but it's the default one
* and doesn't do anything destructive.
*/
int
pru_sense_null(struct socket *so, struct stat *sb)
{
sb->st_blksize = so->so_snd.sb_hiwat;
return 0;
}
int
pru_shutdown_notsupp(struct socket *so)
{
return EOPNOTSUPP;
}
int
pru_sockaddr_notsupp(struct socket *so, struct sockaddr **nam)
{
return EOPNOTSUPP;
}
int
pru_sosend_notsupp(struct socket *so, struct sockaddr *addr, struct uio *uio,
struct mbuf *top, struct mbuf *control, int flags, struct thread *td)
{
return EOPNOTSUPP;
}
int
pru_soreceive_notsupp(struct socket *so, struct sockaddr **paddr,
struct uio *uio, struct mbuf **mp0, struct mbuf **controlp,
int *flagsp)
{
return EOPNOTSUPP;
}
int
pru_sopoll_notsupp(struct socket *so, int events, struct ucred *cred,
struct thread *td)
{
return EOPNOTSUPP;
}
/*
* Make a copy of a sockaddr in a malloced buffer of type M_SONAME.
*/
struct sockaddr *
sodupsockaddr(const struct sockaddr *sa, int mflags)
{
struct sockaddr *sa2;
sa2 = malloc(sa->sa_len, M_SONAME, mflags);
if (sa2)
bcopy(sa, sa2, sa->sa_len);
return sa2;
}
/*
* Create an external-format (``xsocket'') structure using the information
* in the kernel-format socket structure pointed to by so. This is done
* to reduce the spew of irrelevant information over this interface,
* to isolate user code from changes in the kernel structure, and
* potentially to provide information-hiding if we decide that
* some of this information should be hidden from users.
*/
void
sotoxsocket(struct socket *so, struct xsocket *xso)
{
xso->xso_len = sizeof *xso;
xso->xso_so = so;
xso->so_type = so->so_type;
xso->so_options = so->so_options;
xso->so_linger = so->so_linger;
xso->so_state = so->so_state;
xso->so_pcb = so->so_pcb;
xso->xso_protocol = so->so_proto->pr_protocol;
xso->xso_family = so->so_proto->pr_domain->dom_family;
xso->so_qlen = so->so_qlen;
xso->so_incqlen = so->so_incqlen;
xso->so_qlimit = so->so_qlimit;
xso->so_timeo = so->so_timeo;
xso->so_error = so->so_error;
xso->so_pgid = so->so_sigio ? so->so_sigio->sio_pgid : 0;
xso->so_oobmark = so->so_oobmark;
sbtoxsockbuf(&so->so_snd, &xso->so_snd);
sbtoxsockbuf(&so->so_rcv, &xso->so_rcv);
xso->so_uid = so->so_cred->cr_uid;
}
/*
* This does the same for sockbufs. Note that the xsockbuf structure,
* since it is always embedded in a socket, does not include a self
* pointer nor a length. We make this entry point public in case
* some other mechanism needs it.
*/
void
sbtoxsockbuf(struct sockbuf *sb, struct xsockbuf *xsb)
{
xsb->sb_cc = sb->sb_cc;
xsb->sb_hiwat = sb->sb_hiwat;
xsb->sb_mbcnt = sb->sb_mbcnt;
xsb->sb_mbmax = sb->sb_mbmax;
xsb->sb_lowat = sb->sb_lowat;
xsb->sb_flags = sb->sb_flags;
xsb->sb_timeo = sb->sb_timeo;
}