d/freebsd-skq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
3ac364813a
freebsd-skq/sys/security/lomac/kernel_socket.c

814 lines
23 KiB
C
Raw Blame History

/*-
* Copyright (c) 2001 Networks Associates Technology, Inc.
*
* This software was developed for the FreeBSD Project by NAI Labs, the
* Security Research Division of Network Associates, Inc. under
* DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA
* CHATS research program.
*
* 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 the above entities nor the names of any
* contributors of those entities may be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*
* $Id$
*/
/*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 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_socket.c 8.3 (Berkeley) 4/15/94
* $FreeBSD$
*/
/*
* This file implements LOMAC controls over socket operations. LOMAC
* gains control of socket operations by interposing on the `struct
* pr_usrreqs' operations vectors of each `struct protosw'. This code
* replaces each `struct pr_usrreqs' with an instance of `struct
* lomac_pr_usrreqs' containing LOMAC socket control functions. These
* socket control functions implement LOMAC's socket controls, and then
* call the corresponding socket operations from the original `struct
* pr_usrreqs'. Each instance of `struct lomac_pr_usrreqs' ends with
* a pointer to the `struct pr_usrreqs' it replaces. These pointers
* allow the LOMAC socket control functions to find their corresponding
* original `struct pr_usrreqs' functions.
*
* This file provides the function lomac_initialize_sockets() to turn
* socket interposition on. Once socket iterposition is turned on,
* the kernel will begin to call LOMAC's socket control functions.
*/
#include <sys/types.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/resourcevar.h>
#include <sys/domain.h>
#include <sys/mbuf.h>
#include <sys/namei.h>
#include <sys/protosw.h>
#include <sys/socketvar.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <sys/unpcb.h>
#include <sys/uio.h>
#include <sys/vnode.h>
#include "kernel_interface.h"
#include "kernel_socket.h"
#include "kernel_mediate.h"
#include "kernel_monitor.h"
#include "lomacfs.h"
MALLOC_DEFINE(M_LOMAC_USRREQS, "LOMAC-UR", "LOMAC usrreqs");
struct lomac_pr_usrreqs {
struct pr_usrreqs lomac_pr_usrreqs; /* LOMAC socket control fxns */
struct pr_usrreqs *orig_pr_usrreqs; /* original socket op vector */
};
int lomac_local_accept(struct socket *, struct sockaddr **);
int lomac_local_connect(struct socket *, struct sockaddr *, struct thread *);
int lomac_local_connect2(struct socket *, struct socket *);
int lomac_local_detach(struct socket *);
int lomac_local_send( struct socket *, int, struct mbuf *, struct sockaddr *,
struct mbuf *, struct thread * );
int lomac_soreceive( struct socket *, struct sockaddr **, struct uio *,
struct mbuf **, struct mbuf **, int * );
int lomac_local_soreceive( struct socket *, struct sockaddr **, struct uio *,
struct mbuf **, struct mbuf **, int * );
static int monitored_soreceive( struct socket *, struct sockaddr **,
struct uio *, struct mbuf **, struct mbuf **, int * );
/* This usrreqs structure implements LOMAC's controls on local sockets */
struct pr_usrreqs lomac_local_usrreqs = {
NULL,
lomac_local_accept,
NULL,
NULL,
lomac_local_connect,
lomac_local_connect2,
NULL,
lomac_local_detach,
NULL,
NULL,
NULL,
NULL,
NULL,
lomac_local_send,
NULL,
NULL,
NULL,
NULL,
lomac_local_soreceive,
NULL
};
/* This usrreqs structure implements LOMAC's controls on network sockets */
struct pr_usrreqs lomac_net_usrreqs = {
NULL,
NULL,
NULL,
NULL,
NULL,
NULL,
NULL,
NULL,
NULL,
NULL,
NULL,
NULL,
NULL,
NULL,
NULL,
NULL,
NULL,
NULL,
lomac_soreceive,
NULL
};
static __inline struct pr_usrreqs *
orig_pr_usrreqs( struct socket *so ) {
return (((struct lomac_pr_usrreqs *)(so->so_proto->pr_usrreqs))->
orig_pr_usrreqs);
}
int
lomac_local_accept( struct socket *so, struct sockaddr **nam ) {
struct vnode *vp;
struct unpcb *unp;
int ret_val; /* value to return to caller */
unp = sotounpcb(so);
if (unp == NULL)
return (EINVAL);
if (unp->unp_conn != NULL) {
vp = unp->unp_vnode = unp->unp_conn->unp_vnode;
if (vp != NULL)
vref(vp);
}
ret_val = (*orig_pr_usrreqs(so)->pru_accept)(so, nam);
return (ret_val);
}
int
lomac_local_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
{
register struct sockaddr_un *soun = (struct sockaddr_un *)nam;
register struct vnode *vp;
register struct socket *so2, *so3;
struct unpcb *unp, *unp2, *unp3;
int error, len;
struct nameidata nd;
char buf[SOCK_MAXADDRLEN];
len = nam->sa_len - offsetof(struct sockaddr_un, sun_path);
if (len <= 0)
return EINVAL;
strncpy(buf, soun->sun_path, len);
buf[len] = 0;
NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, buf, td);
error = namei(&nd);
if (error)
goto bad2;
vp = nd.ni_vp;
NDFREE(&nd, NDF_ONLY_PNBUF);
if (vp->v_type != VSOCK) {
error = ENOTSOCK;
goto bad;
}
error = VOP_ACCESS(vp, VWRITE, td->td_ucred, td);
if (error)
goto bad;
so2 = vp->v_socket;
if (so2 == 0) {
error = ECONNREFUSED;
goto bad;
}
if (so->so_type != so2->so_type) {
error = EPROTOTYPE;
goto bad;
}
if (so->so_proto->pr_flags & PR_CONNREQUIRED) {
if ((so2->so_options & SO_ACCEPTCONN) == 0 ||
(so3 = sonewconn(so2, 0)) == 0) {
error = ECONNREFUSED;
goto bad;
}
unp = sotounpcb(so);
unp2 = sotounpcb(so2);
unp3 = sotounpcb(so3);
if (unp2->unp_addr)
unp3->unp_addr = (struct sockaddr_un *)
dup_sockaddr((struct sockaddr *)
unp2->unp_addr, 1);
/*
* unp_peercred management:
*
* The connecter's (client's) credentials are copied
* from its process structure at the time of connect()
* (which is now).
*/
cru2x(td->td_ucred, &unp3->unp_peercred);
unp3->unp_flags |= UNP_HAVEPC;
/*
* The receiver's (server's) credentials are copied
* from the unp_peercred member of socket on which the
* former called listen(); unp_listen() cached that
* process's credentials at that time so we can use
* them now.
*/
KASSERT(unp2->unp_flags & UNP_HAVEPCCACHED,
("unp_connect: listener without cached peercred"));
memcpy(&unp->unp_peercred, &unp2->unp_peercred,
sizeof(unp->unp_peercred));
unp->unp_flags |= UNP_HAVEPC;
so2 = so3;
}
error = lomac_local_connect2(so, so2);
bad:
vput(vp);
bad2:
return (error);
}
int
lomac_local_connect2( struct socket *so1, struct socket *so2 ) {
struct vnode *vp;
int ret_val; /* value to return to caller */
if (so2->so_head != NULL) {
vp = sotounpcb(so2->so_head)->unp_vnode;
if (vp != NULL) {
sotounpcb(so1)->unp_vnode = vp;
vref(vp);
}
}
ret_val = (*orig_pr_usrreqs(so1)->pru_connect2)(so1, so2);
return (ret_val);
}
int
lomac_local_detach( struct socket *so ) {
int ret_val; /* value to return to caller */
struct unpcb *unp = sotounpcb(so);
if (unp == NULL)
return (EINVAL);
if (unp->unp_vnode != NULL && unp->unp_vnode->v_socket != so) {
vrele(unp->unp_vnode);
unp->unp_vnode = NULL;
}
ret_val = (*orig_pr_usrreqs(so)->pru_detach)(so);
return (ret_val);
}
int
lomac_local_send( struct socket *so, int flags, struct mbuf *m,
struct sockaddr *addr, struct mbuf *control, struct thread *td ) {
struct vnode *vp;
struct unpcb *unp = sotounpcb(so);
int error;
/* printf( "pid %d local send\n", p->p_pid ); */
if (unp == NULL) {
error = EINVAL;
goto out;
}
if (so->so_type == SOCK_DGRAM) {
if (addr != NULL) {
if (unp->unp_conn != NULL) {
error = EISCONN;
goto out;
}
error = lomac_local_connect(so, addr, td);
if (error)
goto out;
} else if (unp->unp_conn == NULL) {
error = ENOTCONN;
goto out;
}
} else if ((so->so_state & SS_ISCONNECTED) == 0) {
if (addr != NULL) {
error = lomac_local_connect(so, addr, td);
if (error)
goto out; /* XXX */
} else {
error = ENOTCONN;
goto out;
}
}
vp = unp->unp_vnode;
if (vp != NULL) {
lomac_object_t lobj;
lobj.lo_type = VISLOMAC(vp) ? LO_TYPE_LVNODE : LO_TYPE_UVNODE;
lobj.lo_object.vnode = vp;
if (!mediate_subject_object("send", td->td_proc, &lobj)) {
error = EPERM;
goto out;
}
} else {
/*
* This is a send to a socket in a socketpair() pair.
* Mark both sockets in pair with the appropriate level.
*/
lomac_object_t lobj1, lobj2;
lattr_t lattr;
lobj1.lo_type = LO_TYPE_SOCKETPAIR;
lobj1.lo_object.socket = so;
if ((error = monitor_pipe_write(td->td_proc, &lobj1)) != 0)
goto out;
lobj2.lo_type = LO_TYPE_SOCKETPAIR;
lobj2.lo_object.socket = unp->unp_conn->unp_socket;
get_object_lattr(&lobj1, &lattr);
set_object_lattr(&lobj2, lattr);
}
error = (*orig_pr_usrreqs(so)->pru_send)( so, flags, m, NULL,
control, td );
if (addr != NULL && so->so_type == SOCK_DGRAM)
(*orig_pr_usrreqs(so)->pru_disconnect)(so);
out:
return (error);
}
int
lomac_local_soreceive(struct socket *so, struct sockaddr **paddr,
struct uio *uio, struct mbuf **mp0, struct mbuf **controlp, int *flagsp) {
lomac_object_t lobj;
struct vnode *vp;
struct unpcb *unp = sotounpcb(so);
int ret_val; /* value to return to caller */
if (unp == NULL)
return (EINVAL);
vp = unp->unp_vnode;
if (vp != NULL) {
lobj.lo_type = VISLOMAC(vp) ? LO_TYPE_LVNODE : LO_TYPE_UVNODE;
lobj.lo_object.vnode = vp;
ret_val = monitor_read_object(uio->uio_td->td_proc, &lobj);
if (ret_val == 0)
ret_val = (*orig_pr_usrreqs(so)->pru_soreceive)(so,
paddr, uio, mp0, controlp, flagsp);
} else {
/*
* This is a receive from a socket in a pair created by
* socketpair(). Monitor it as we would a pipe read,
* except for allowing for arbitrary numbers of sleeps.
*/
ret_val = monitored_soreceive(so, paddr, uio, mp0, controlp,
flagsp);
}
return (ret_val);
}
int
lomac_soreceive(struct socket *so, struct sockaddr **paddr, struct uio *uio,
struct mbuf **mp0, struct mbuf **controlp, int *flagsp) {
int ret_val; /* value to return to caller */
(void)monitor_read_net_socket(uio->uio_td->td_proc);
ret_val = (*orig_pr_usrreqs(so)->pru_soreceive)(so, paddr, uio, mp0,
controlp, flagsp);
return (ret_val);
}
int
lomac_initialize_sockets(void) {
struct domain *dp; /* used to traverse global `domains' list */
struct protosw *pr; /* used to traverse each domain's protosw list */
struct lomac_pr_usrreqs *lomac_pr_usrreqs; /* lomac usrreqs vectors */
void (**lfuncp)(void), (**funcp)(void);
int n, nreq;
nreq = sizeof(struct pr_usrreqs) / sizeof(void (*)(void));
for (dp = domains; dp; dp = dp->dom_next) {
for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) {
lomac_pr_usrreqs = (struct lomac_pr_usrreqs *)malloc(
sizeof(struct lomac_pr_usrreqs), M_LOMAC_USRREQS,
M_WAITOK);
if (dp->dom_family == AF_LOCAL)
memcpy(lomac_pr_usrreqs, &lomac_local_usrreqs,
sizeof(struct pr_usrreqs));
else
memcpy(lomac_pr_usrreqs, &lomac_net_usrreqs,
sizeof(struct pr_usrreqs));
/*
* Do sparse allocation of user requests and only
* override the ones we need to (to reduce overhead).
*/
lfuncp = (void (**)(void))lomac_pr_usrreqs;
funcp = (void (**)(void))pr->pr_usrreqs;
for (n = 0; n < nreq; n++) {
if (lfuncp[n] == NULL)
lfuncp[n] = funcp[n];
}
lomac_pr_usrreqs->orig_pr_usrreqs = pr->pr_usrreqs;
pr->pr_usrreqs = (struct pr_usrreqs *)lomac_pr_usrreqs;
}
}
return (0);
}
int
lomac_uninitialize_sockets(void) {
struct domain *dp; /* used to traverse global `domains' list */
struct protosw *pr; /* used to traverse each domain's protosw list */
struct lomac_pr_usrreqs *lomac_pr_usrreqs; /* lomac usrreqs vectors */
for (dp = domains; dp; dp = dp->dom_next) {
for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) {
lomac_pr_usrreqs = (struct lomac_pr_usrreqs *)
pr->pr_usrreqs;
pr->pr_usrreqs = lomac_pr_usrreqs->orig_pr_usrreqs;
free(lomac_pr_usrreqs, M_LOMAC_USRREQS);
}
}
return (0);
}
#define SBLOCKWAIT(f) (((f) & MSG_DONTWAIT) ? M_NOWAIT : M_WAITOK)
/*
* Implement receive operations on a socket.
* We depend on the way that records are added to the sockbuf
* by sbappend*. In particular, each record (mbufs linked through m_next)
* must begin with an address if the protocol so specifies,
* followed by an optional mbuf or mbufs containing ancillary data,
* and then zero or more mbufs of data.
* In order to avoid blocking network interrupts for the entire time here,
* we splx() while doing the actual copy to user space.
* Although the sockbuf is locked, new data may still be appended,
* and thus we must maintain consistency of the sockbuf during that time.
*
* The caller may receive the data as a single mbuf chain by supplying
* an mbuf **mp0 for use in returning the chain. The uio is then used
* only for the count in uio_resid.
*/
static int
monitored_soreceive(so, psa, uio, mp0, controlp, flagsp)
register struct socket *so;
struct sockaddr **psa;
struct uio *uio;
struct mbuf **mp0;
struct mbuf **controlp;
int *flagsp;
{
lomac_object_t lobj;
register struct mbuf *m, **mp;
register int flags, len, error, s, offset;
struct protosw *pr = so->so_proto;
struct mbuf *nextrecord;
struct proc *p;
int moff, type = 0;
int orig_resid = uio->uio_resid;
mp = mp0;
if (psa)
*psa = 0;
if (controlp)
*controlp = 0;
if (flagsp)
flags = *flagsp &~ MSG_EOR;
else
flags = 0;
lobj.lo_type = LO_TYPE_SOCKETPAIR;
lobj.lo_object.socket = so;
if (uio->uio_td != NULL) /* XXX */
p = uio->uio_td->td_proc;
else
p = curthread->td_proc;
if (flags & MSG_OOB) {
m = m_get(M_TRYWAIT, MT_DATA);
if (m == NULL)
return (ENOBUFS);
error = (*pr->pr_usrreqs->pru_rcvoob)(so, m, flags & MSG_PEEK);
if (error)
goto bad;
do {
monitor_read_object(p, &lobj);
error = uiomove(mtod(m, caddr_t),
(int) min(uio->uio_resid, m->m_len), uio);
m = m_free(m);
} while (uio->uio_resid && error == 0 && m);
bad:
if (m)
m_freem(m);
return (error);
}
if (mp)
*mp = (struct mbuf *)0;
if (so->so_state & SS_ISCONFIRMING && uio->uio_resid)
(*pr->pr_usrreqs->pru_rcvd)(so, 0);
restart:
error = sblock(&so->so_rcv, SBLOCKWAIT(flags));
if (error)
return (error);
s = splnet();
m = so->so_rcv.sb_mb;
/*
* If we have less data than requested, block awaiting more
* (subject to any timeout) if:
* 1. the current count is less than the low water mark, or
* 2. MSG_WAITALL is set, and it is possible to do the entire
* receive operation at once if we block (resid <= hiwat).
* 3. MSG_DONTWAIT is not set
* If MSG_WAITALL is set but resid is larger than the receive buffer,
* we have to do the receive in sections, and thus risk returning
* a short count if a timeout or signal occurs after we start.
*/
if (m == 0 || (((flags & MSG_DONTWAIT) == 0 &&
so->so_rcv.sb_cc < uio->uio_resid) &&
(so->so_rcv.sb_cc < so->so_rcv.sb_lowat ||
((flags & MSG_WAITALL) && uio->uio_resid <= so->so_rcv.sb_hiwat)) &&
m->m_nextpkt == 0 && (pr->pr_flags & PR_ATOMIC) == 0)) {
KASSERT(m != 0 || !so->so_rcv.sb_cc,
("receive: m == %p so->so_rcv.sb_cc == %lu",
m, so->so_rcv.sb_cc));
if (so->so_error) {
if (m)
goto dontblock;
error = so->so_error;
if ((flags & MSG_PEEK) == 0)
so->so_error = 0;
goto release;
}
if (so->so_state & SS_CANTRCVMORE) {
if (m)
goto dontblock;
else
goto release;
}
for (; m; m = m->m_next)
if (m->m_type == MT_OOBDATA || (m->m_flags & M_EOR)) {
m = so->so_rcv.sb_mb;
goto dontblock;
}
if ((so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) == 0 &&
(so->so_proto->pr_flags & PR_CONNREQUIRED)) {
error = ENOTCONN;
goto release;
}
if (uio->uio_resid == 0)
goto release;
if ((so->so_state & SS_NBIO) || (flags & MSG_DONTWAIT)) {
error = EWOULDBLOCK;
goto release;
}
sbunlock(&so->so_rcv);
error = sbwait(&so->so_rcv);
splx(s);
if (error)
return (error);
goto restart;
}
dontblock:
if (uio->uio_td)
p->p_stats->p_ru.ru_msgrcv++;
nextrecord = m->m_nextpkt;
if (pr->pr_flags & PR_ADDR) {
KASSERT(m->m_type == MT_SONAME, ("receive 1a"));
orig_resid = 0;
if (psa)
*psa = dup_sockaddr(mtod(m, struct sockaddr *),
mp0 == 0);
if (flags & MSG_PEEK) {
m = m->m_next;
} else {
sbfree(&so->so_rcv, m);
so->so_rcv.sb_mb = m_free(m);
m = so->so_rcv.sb_mb;
}
}
while (m && m->m_type == MT_CONTROL && error == 0) {
if (flags & MSG_PEEK) {
if (controlp)
*controlp = m_copy(m, 0, m->m_len);
m = m->m_next;
} else {
sbfree(&so->so_rcv, m);
so->so_rcv.sb_mb = m->m_next;
m->m_next = NULL;
if (pr->pr_domain->dom_externalize)
error =
(*pr->pr_domain->dom_externalize)(m, controlp);
else if (controlp)
*controlp = m;
else
m_freem(m);
m = so->so_rcv.sb_mb;
}
if (controlp) {
orig_resid = 0;
do
controlp = &(*controlp)->m_next;
while (*controlp != NULL);
}
}
if (m) {
if ((flags & MSG_PEEK) == 0)
m->m_nextpkt = nextrecord;
type = m->m_type;
if (type == MT_OOBDATA)
flags |= MSG_OOB;
}
moff = 0;
offset = 0;
while (m && uio->uio_resid > 0 && error == 0) {
if (m->m_type == MT_OOBDATA) {
if (type != MT_OOBDATA)
break;
} else if (type == MT_OOBDATA)
break;
else
KASSERT(m->m_type == MT_DATA || m->m_type == MT_HEADER,
("receive 3"));
so->so_state &= ~SS_RCVATMARK;
len = uio->uio_resid;
if (so->so_oobmark && len > so->so_oobmark - offset)
len = so->so_oobmark - offset;
if (len > m->m_len - moff)
len = m->m_len - moff;
/*
* If mp is set, just pass back the mbufs.
* Otherwise copy them out via the uio, then free.
* Sockbuf must be consistent here (points to current mbuf,
* it points to next record) when we drop priority;
* we must note any additions to the sockbuf when we
* block interrupts again.
*/
if (mp == 0) {
splx(s);
monitor_read_object(p, &lobj);
error = uiomove(mtod(m, caddr_t) + moff, (int)len, uio);
s = splnet();
if (error)
goto release;
} else
uio->uio_resid -= len;
if (len == m->m_len - moff) {
if (m->m_flags & M_EOR)
flags |= MSG_EOR;
if (flags & MSG_PEEK) {
m = m->m_next;
moff = 0;
} else {
nextrecord = m->m_nextpkt;
sbfree(&so->so_rcv, m);
if (mp) {
*mp = m;
mp = &m->m_next;
so->so_rcv.sb_mb = m = m->m_next;
*mp = (struct mbuf *)0;
} else {
so->so_rcv.sb_mb = m_free(m);
m = so->so_rcv.sb_mb;
}
if (m)
m->m_nextpkt = nextrecord;
}
} else {
if (flags & MSG_PEEK)
moff += len;
else {
if (mp)
*mp = m_copym(m, 0, len, M_TRYWAIT);
m->m_data += len;
m->m_len -= len;
so->so_rcv.sb_cc -= len;
}
}
if (so->so_oobmark) {
if ((flags & MSG_PEEK) == 0) {
so->so_oobmark -= len;
if (so->so_oobmark == 0) {
so->so_state |= SS_RCVATMARK;
break;
}
} else {
offset += len;
if (offset == so->so_oobmark)
break;
}
}
if (flags & MSG_EOR)
break;
/*
* If the MSG_WAITALL flag is set (for non-atomic socket),
* we must not quit until "uio->uio_resid == 0" or an error
* termination. If a signal/timeout occurs, return
* with a short count but without error.
* Keep sockbuf locked against other readers.
*/
while (flags & MSG_WAITALL && m == 0 && uio->uio_resid > 0 &&
!sosendallatonce(so) && !nextrecord) {
if (so->so_error || so->so_state & SS_CANTRCVMORE)
break;
/*
* Notify the protocol that some data has been
* drained before blocking.
*/
if (pr->pr_flags & PR_WANTRCVD && so->so_pcb)
(*pr->pr_usrreqs->pru_rcvd)(so, flags);
error = sbwait(&so->so_rcv);
if (error) {
sbunlock(&so->so_rcv);
splx(s);
return (0);
}
m = so->so_rcv.sb_mb;
if (m)
nextrecord = m->m_nextpkt;
}
}
if (m && pr->pr_flags & PR_ATOMIC) {
flags |= MSG_TRUNC;
if ((flags & MSG_PEEK) == 0)
(void) sbdroprecord(&so->so_rcv);
}
if ((flags & MSG_PEEK) == 0) {
if (m == 0)
so->so_rcv.sb_mb = nextrecord;
if (pr->pr_flags & PR_WANTRCVD && so->so_pcb)
(*pr->pr_usrreqs->pru_rcvd)(so, flags);
}
if (orig_resid == uio->uio_resid && orig_resid &&
(flags & MSG_EOR) == 0 && (so->so_state & SS_CANTRCVMORE) == 0) {
sbunlock(&so->so_rcv);
splx(s);
goto restart;
}
if (flagsp)
*flagsp |= flags;
release:
sbunlock(&so->so_rcv);
splx(s);
return (error);
}
Reference in New Issue View Git Blame Copy Permalink