📄 uipc_socket.c
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snderr(ENOTCONN);
} else if (addr == 0)
snderr(so->so_proto->pr_flags & PR_CONNREQUIRED ?
ENOTCONN : EDESTADDRREQ);
}
space = sbspace(&so->so_snd);
if (flags & MSG_OOB)
space += 1024;
if ((atomic && resid > so->so_snd.sb_hiwat) ||
clen > so->so_snd.sb_hiwat)
snderr(EMSGSIZE);
if (space < resid + clen && uio &&
(atomic || space < so->so_snd.sb_lowat || space < clen)) {
if (so->so_state & SS_NBIO)
snderr(EWOULDBLOCK);
sbunlock(&so->so_snd);
error = sbwait(&so->so_snd);
splx(s);
if (error)
goto out;
goto restart;
}
splx(s);
mp = ⊤
space -= clen;
do {
if (uio == NULL) {
/*
* Data is prepackaged in "top".
*/
resid = 0;
if (flags & MSG_EOR)
top->m_flags |= M_EOR;
} else do {
if (top == 0) {
MGETHDR(m, M_WAIT, MT_DATA);
if (m == NULL) {
error = ENOBUFS;
goto release;
}
mlen = MHLEN;
m->m_pkthdr.len = 0;
m->m_pkthdr.rcvif = (struct ifnet *)0;
} else {
MGET(m, M_WAIT, MT_DATA);
if (m == NULL) {
error = ENOBUFS;
goto release;
}
mlen = MLEN;
}
if (resid >= MINCLSIZE) {
MCLGET(m, M_WAIT);
if ((m->m_flags & M_EXT) == 0)
goto nopages;
mlen = MCLBYTES;
len = min(min(mlen, resid), space);
} else {
nopages:
len = min(min(mlen, resid), space);
/*
* For datagram protocols, leave room
* for protocol headers in first mbuf.
*/
if (atomic && top == 0 && len < mlen)
MH_ALIGN(m, len);
}
space -= len;
error = uiomove(mtod(m, caddr_t), (int)len, uio);
resid = uio->uio_resid;
m->m_len = len;
*mp = m;
top->m_pkthdr.len += len;
if (error)
goto release;
mp = &m->m_next;
if (resid <= 0) {
if (flags & MSG_EOR)
top->m_flags |= M_EOR;
break;
}
} while (space > 0 && atomic);
if (dontroute)
so->so_options |= SO_DONTROUTE;
s = splnet(); /* XXX */
/*
* XXX all the SS_CANTSENDMORE checks previously
* done could be out of date. We could have recieved
* a reset packet in an interrupt or maybe we slept
* while doing page faults in uiomove() etc. We could
* probably recheck again inside the splnet() protection
* here, but there are probably other places that this
* also happens. We must rethink this.
*/
error = (*so->so_proto->pr_usrreqs->pru_send)(so,
(flags & MSG_OOB) ? PRUS_OOB :
/*
* If the user set MSG_EOF, the protocol
* understands this flag and nothing left to
* send then use PRU_SEND_EOF instead of PRU_SEND.
*/
((flags & MSG_EOF) &&
(so->so_proto->pr_flags & PR_IMPLOPCL) &&
(resid <= 0)) ?
PRUS_EOF :
/* If there is more to send set PRUS_MORETOCOME */
(resid > 0 && space > 0) ? PRUS_MORETOCOME : 0,
top, addr, control, p);
splx(s);
if (dontroute)
so->so_options &= ~SO_DONTROUTE;
clen = 0;
control = 0;
top = 0;
mp = ⊤
if (error)
goto release;
} while (resid && space > 0);
} while (resid);
release:
sbunlock(&so->so_snd);
out:
if (top)
m_freem(top);
if (control)
m_freem(control);
return (error);
}
/*
* 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.
*/
int
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;
{
register struct mbuf *m, **mp;
register int flags, len, error, s, offset;
struct protosw *pr = so->so_proto;
struct mbuf *nextrecord;
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;
if (flags & MSG_OOB) {
m = m_get(M_WAIT, MT_DATA);
if (m == NULL) {
return (ENOBUFS);
}
error = (*pr->pr_usrreqs->pru_rcvoob)(so, m, flags & MSG_PEEK);
if (error)
goto bad;
do {
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)) {
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:
nextrecord = m->m_nextpkt;
if (pr->pr_flags & PR_ADDR) {
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);
MFREE(m, so->so_rcv.sb_mb);
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);
if (controlp) {
if (pr->pr_domain->dom_externalize &&
mtod(m, struct cmsghdr *)->cmsg_type ==
SCM_RIGHTS)
error = (*pr->pr_domain->dom_externalize)(m);
*controlp = m;
so->so_rcv.sb_mb = m->m_next;
m->m_next = 0;
m = so->so_rcv.sb_mb;
} else {
MFREE(m, so->so_rcv.sb_mb);
m = so->so_rcv.sb_mb;
}
}
if (controlp) {
orig_resid = 0;
controlp = &(*controlp)->m_next;
}
}
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;
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);
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 {
MFREE(m, so->so_rcv.sb_mb);
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_WAIT);
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;
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);
}
int
soshutdown(so, how)
register struct socket *so;
register int how;
{
register struct protosw *pr = so->so_proto;
if (!(how == SHUT_RD || how == SHUT_WR || how == SHUT_RDWR))
return (EINVAL);
if (how != SHUT_WR)
sorflush(so);
if (how != SHUT_RD)
return ((*pr->pr_usrreqs->pru_shutdown)(so));
return (0);
}
void
sorflush(so)
register struct socket *so;
{
register struct sockbuf *sb = &so->so_rcv;
register struct protosw *pr = so->so_proto;
register int s;
struct sockbuf asb;
sb->sb_flags |= SB_NOINTR;
(void) sblock(sb, M_WAITOK);
s = splimp();
socantrcvmore(so);
sbunlock(sb);
asb = *sb;
bzero((caddr_t)sb, sizeof (*sb));
splx(s);
if (pr->pr_flags & PR_RIGHTS && pr->pr_domain->dom_dispose)
(*pr->pr_domain->dom_dispose)(asb.sb_mb);
sbrelease(&asb, so);
}
#ifdef INET
static int
do_setopt_accept_filter(so, sopt)
struct socket *so;
struct sockopt *sopt;
{
struct accept_filter_arg *afap = NULL;
struct accept_filter *afp;
struct so_accf *af = so->so_accf;
int error = 0;
/* do not set/remove accept filters on non listen sockets */
if ((so->so_options & SO_ACCEPTCONN) == 0) {
error = EINVAL;
goto out;
}
/* removing the filter */
if (sopt == NULL) {
if (af != NULL) {
if (af->so_accept_filter != NULL &&
af->so_accept_filter->accf_destroy != NULL) {
af->so_accept_filter->accf_destroy(so);
}
if (af->so_accept_filter_str != NULL) {
FREE(af->so_accept_filter_str, M_ACCF);
}
FREE(af, M_ACCF);
so->so_accf = NULL;
}
so->so_options &= ~SO_ACCEPTFILTER;
return (0);
}
/* adding a filter */
/* must remove previous filter first */
if (af != NULL) {
error = EINVAL;
goto out;
}
/* don't put large objects on the kernel stack */
MALLOC(afap, struct accept_filter_arg *, sizeof(*afap), M_TEMP, M_WAITOK);
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