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6b0018e885
freebsd-skq/sys/netinet/udp_usrreq.c
jamie 12bbe1869f Standardize the various prison_foo_ip[46] functions and prison_if to 
return zero on success and an error code otherwise.  The possible errors
are EADDRNOTAVAIL if an address being checked for doesn't match the
prison, and EAFNOSUPPORT if the prison doesn't have any addresses in
that address family.  For most callers of these functions, use the
returned error code instead of e.g. a hard-coded EADDRNOTAVAIL or
EINVAL.

Always include a jailed() check in these functions, where a non-jailed
cred always returns success (and makes no changes).  Remove the explicit
jailed() checks that preceded many of the function calls.

Approved by:	bz (mentor)
2009-02-05 14:06:09 +00:00

1371 lines
34 KiB
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/*-
* Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995
* The Regents of the University of California.
* Copyright (c) 2008 Robert N. M. Watson
* 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.
*
* @(#)udp_usrreq.c 8.6 (Berkeley) 5/23/95
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_ipfw.h"
#include "opt_inet6.h"
#include "opt_ipsec.h"
#include "opt_mac.h"
#include <sys/param.h>
#include <sys/domain.h>
#include <sys/eventhandler.h>
#include <sys/jail.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/priv.h>
#include <sys/proc.h>
#include <sys/protosw.h>
#include <sys/signalvar.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sx.h>
#include <sys/sysctl.h>
#include <sys/syslog.h>
#include <sys/systm.h>
#include <sys/vimage.h>
#include <vm/uma.h>
#include <net/if.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/in_pcb.h>
#include <netinet/in_systm.h>
#include <netinet/in_var.h>
#include <netinet/ip.h>
#ifdef INET6
#include <netinet/ip6.h>
#endif
#include <netinet/ip_icmp.h>
#include <netinet/icmp_var.h>
#include <netinet/ip_var.h>
#include <netinet/ip_options.h>
#ifdef INET6
#include <netinet6/ip6_var.h>
#endif
#include <netinet/udp.h>
#include <netinet/udp_var.h>
#include <netinet/vinet.h>
#ifdef IPSEC
#include <netipsec/ipsec.h>
#endif
#include <machine/in_cksum.h>
#include <security/mac/mac_framework.h>
/*
* UDP protocol implementation.
* Per RFC 768, August, 1980.
*/
#ifdef VIMAGE_GLOBALS
int udp_blackhole;
#endif
/*
* BSD 4.2 defaulted the udp checksum to be off. Turning off udp checksums
* removes the only data integrity mechanism for packets and malformed
* packets that would otherwise be discarded due to bad checksums, and may
* cause problems (especially for NFS data blocks).
*/
static int udp_cksum = 1;
SYSCTL_INT(_net_inet_udp, UDPCTL_CHECKSUM, checksum, CTLFLAG_RW, &udp_cksum,
0, "compute udp checksum");
int udp_log_in_vain = 0;
SYSCTL_INT(_net_inet_udp, OID_AUTO, log_in_vain, CTLFLAG_RW,
&udp_log_in_vain, 0, "Log all incoming UDP packets");
SYSCTL_V_INT(V_NET, vnet_inet, _net_inet_udp, OID_AUTO, blackhole,
CTLFLAG_RW, udp_blackhole, 0,
"Do not send port unreachables for refused connects");
u_long udp_sendspace = 9216; /* really max datagram size */
/* 40 1K datagrams */
SYSCTL_ULONG(_net_inet_udp, UDPCTL_MAXDGRAM, maxdgram, CTLFLAG_RW,
&udp_sendspace, 0, "Maximum outgoing UDP datagram size");
u_long udp_recvspace = 40 * (1024 +
#ifdef INET6
sizeof(struct sockaddr_in6)
#else
sizeof(struct sockaddr_in)
#endif
);
SYSCTL_ULONG(_net_inet_udp, UDPCTL_RECVSPACE, recvspace, CTLFLAG_RW,
&udp_recvspace, 0, "Maximum space for incoming UDP datagrams");
#ifdef VIMAGE_GLOBALS
struct inpcbhead udb; /* from udp_var.h */
struct inpcbinfo udbinfo;
struct udpstat udpstat; /* from udp_var.h */
#endif
#ifndef UDBHASHSIZE
#define UDBHASHSIZE 128
#endif
SYSCTL_V_STRUCT(V_NET, vnet_inet, _net_inet_udp, UDPCTL_STATS, stats,
CTLFLAG_RW, udpstat, udpstat,
"UDP statistics (struct udpstat, netinet/udp_var.h)");
static void udp_detach(struct socket *so);
static int udp_output(struct inpcb *, struct mbuf *, struct sockaddr *,
struct mbuf *, struct thread *);
static void
udp_zone_change(void *tag)
{
uma_zone_set_max(V_udbinfo.ipi_zone, maxsockets);
}
static int
udp_inpcb_init(void *mem, int size, int flags)
{
struct inpcb *inp;
inp = mem;
INP_LOCK_INIT(inp, "inp", "udpinp");
return (0);
}
void
udp_init(void)
{
INIT_VNET_INET(curvnet);
V_udp_blackhole = 0;
INP_INFO_LOCK_INIT(&V_udbinfo, "udp");
LIST_INIT(&V_udb);
V_udbinfo.ipi_listhead = &V_udb;
V_udbinfo.ipi_hashbase = hashinit(UDBHASHSIZE, M_PCB,
&V_udbinfo.ipi_hashmask);
V_udbinfo.ipi_porthashbase = hashinit(UDBHASHSIZE, M_PCB,
&V_udbinfo.ipi_porthashmask);
V_udbinfo.ipi_zone = uma_zcreate("udpcb", sizeof(struct inpcb), NULL,
NULL, udp_inpcb_init, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE);
uma_zone_set_max(V_udbinfo.ipi_zone, maxsockets);
EVENTHANDLER_REGISTER(maxsockets_change, udp_zone_change, NULL,
EVENTHANDLER_PRI_ANY);
}
/*
* Subroutine of udp_input(), which appends the provided mbuf chain to the
* passed pcb/socket. The caller must provide a sockaddr_in via udp_in that
* contains the source address. If the socket ends up being an IPv6 socket,
* udp_append() will convert to a sockaddr_in6 before passing the address
* into the socket code.
*/
static void
udp_append(struct inpcb *inp, struct ip *ip, struct mbuf *n, int off,
struct sockaddr_in *udp_in)
{
struct sockaddr *append_sa;
struct socket *so;
struct mbuf *opts = 0;
#ifdef INET6
struct sockaddr_in6 udp_in6;
#endif
INP_RLOCK_ASSERT(inp);
#ifdef IPSEC
/* Check AH/ESP integrity. */
if (ipsec4_in_reject(n, inp)) {
INIT_VNET_IPSEC(curvnet);
m_freem(n);
V_ipsec4stat.in_polvio++;
return;
}
#endif /* IPSEC */
#ifdef MAC
if (mac_inpcb_check_deliver(inp, n) != 0) {
m_freem(n);
return;
}
#endif
if (inp->inp_flags & INP_CONTROLOPTS ||
inp->inp_socket->so_options & (SO_TIMESTAMP | SO_BINTIME)) {
#ifdef INET6
if (inp->inp_vflag & INP_IPV6)
(void)ip6_savecontrol_v4(inp, n, &opts, NULL);
else
#endif
ip_savecontrol(inp, &opts, ip, n);
}
#ifdef INET6
if (inp->inp_vflag & INP_IPV6) {
bzero(&udp_in6, sizeof(udp_in6));
udp_in6.sin6_len = sizeof(udp_in6);
udp_in6.sin6_family = AF_INET6;
in6_sin_2_v4mapsin6(udp_in, &udp_in6);
append_sa = (struct sockaddr *)&udp_in6;
} else
#endif
append_sa = (struct sockaddr *)udp_in;
m_adj(n, off);
so = inp->inp_socket;
SOCKBUF_LOCK(&so->so_rcv);
if (sbappendaddr_locked(&so->so_rcv, append_sa, n, opts) == 0) {
INIT_VNET_INET(so->so_vnet);
SOCKBUF_UNLOCK(&so->so_rcv);
m_freem(n);
if (opts)
m_freem(opts);
V_udpstat.udps_fullsock++;
} else
sorwakeup_locked(so);
}
void
udp_input(struct mbuf *m, int off)
{
INIT_VNET_INET(curvnet);
int iphlen = off;
struct ip *ip;
struct udphdr *uh;
struct ifnet *ifp;
struct inpcb *inp;
int len;
struct ip save_ip;
struct sockaddr_in udp_in;
#ifdef IPFIREWALL_FORWARD
struct m_tag *fwd_tag;
#endif
ifp = m->m_pkthdr.rcvif;
V_udpstat.udps_ipackets++;
/*
* Strip IP options, if any; should skip this, make available to
* user, and use on returned packets, but we don't yet have a way to
* check the checksum with options still present.
*/
if (iphlen > sizeof (struct ip)) {
ip_stripoptions(m, (struct mbuf *)0);
iphlen = sizeof(struct ip);
}
/*
* Get IP and UDP header together in first mbuf.
*/
ip = mtod(m, struct ip *);
if (m->m_len < iphlen + sizeof(struct udphdr)) {
if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == 0) {
V_udpstat.udps_hdrops++;
return;
}
ip = mtod(m, struct ip *);
}
uh = (struct udphdr *)((caddr_t)ip + iphlen);
/*
* Destination port of 0 is illegal, based on RFC768.
*/
if (uh->uh_dport == 0)
goto badunlocked;
/*
* Construct sockaddr format source address. Stuff source address
* and datagram in user buffer.
*/
bzero(&udp_in, sizeof(udp_in));
udp_in.sin_len = sizeof(udp_in);
udp_in.sin_family = AF_INET;
udp_in.sin_port = uh->uh_sport;
udp_in.sin_addr = ip->ip_src;
/*
* Make mbuf data length reflect UDP length. If not enough data to
* reflect UDP length, drop.
*/
len = ntohs((u_short)uh->uh_ulen);
if (ip->ip_len != len) {
if (len > ip->ip_len || len < sizeof(struct udphdr)) {
V_udpstat.udps_badlen++;
goto badunlocked;
}
m_adj(m, len - ip->ip_len);
/* ip->ip_len = len; */
}
/*
* Save a copy of the IP header in case we want restore it for
* sending an ICMP error message in response.
*/
if (!V_udp_blackhole)
save_ip = *ip;
else
memset(&save_ip, 0, sizeof(save_ip));
/*
* Checksum extended UDP header and data.
*/
if (uh->uh_sum) {
u_short uh_sum;
if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) {
if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
uh_sum = m->m_pkthdr.csum_data;
else
uh_sum = in_pseudo(ip->ip_src.s_addr,
ip->ip_dst.s_addr, htonl((u_short)len +
m->m_pkthdr.csum_data + IPPROTO_UDP));
uh_sum ^= 0xffff;
} else {
char b[9];
bcopy(((struct ipovly *)ip)->ih_x1, b, 9);
bzero(((struct ipovly *)ip)->ih_x1, 9);
((struct ipovly *)ip)->ih_len = uh->uh_ulen;
uh_sum = in_cksum(m, len + sizeof (struct ip));
bcopy(b, ((struct ipovly *)ip)->ih_x1, 9);
}
if (uh_sum) {
V_udpstat.udps_badsum++;
m_freem(m);
return;
}
} else
V_udpstat.udps_nosum++;
#ifdef IPFIREWALL_FORWARD
/*
* Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain.
*/
fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL);
if (fwd_tag != NULL) {
struct sockaddr_in *next_hop;
/*
* Do the hack.
*/
next_hop = (struct sockaddr_in *)(fwd_tag + 1);
ip->ip_dst = next_hop->sin_addr;
uh->uh_dport = ntohs(next_hop->sin_port);
/*
* Remove the tag from the packet. We don't need it anymore.
*/
m_tag_delete(m, fwd_tag);
}
#endif
INP_INFO_RLOCK(&V_udbinfo);
if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) ||
in_broadcast(ip->ip_dst, ifp)) {
struct inpcb *last;
struct ip_moptions *imo;
last = NULL;
LIST_FOREACH(inp, &V_udb, inp_list) {
if (inp->inp_lport != uh->uh_dport)
continue;
#ifdef INET6
if ((inp->inp_vflag & INP_IPV4) == 0)
continue;
#endif
if (inp->inp_laddr.s_addr != INADDR_ANY &&
inp->inp_laddr.s_addr != ip->ip_dst.s_addr)
continue;
if (inp->inp_faddr.s_addr != INADDR_ANY &&
inp->inp_faddr.s_addr != ip->ip_src.s_addr)
continue;
/*
* XXX: Do not check source port of incoming datagram
* unless inp_connect() has been called to bind the
* fport part of the 4-tuple; the source could be
* trying to talk to us with an ephemeral port.
*/
if (inp->inp_fport != 0 &&
inp->inp_fport != uh->uh_sport)
continue;
INP_RLOCK(inp);
/*
* Handle socket delivery policy for any-source
* and source-specific multicast. [RFC3678]
*/
imo = inp->inp_moptions;
if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) &&
imo != NULL) {
struct sockaddr_in sin;
struct in_msource *ims;
int blocked, mode;
size_t idx;
bzero(&sin, sizeof(struct sockaddr_in));
sin.sin_len = sizeof(struct sockaddr_in);
sin.sin_family = AF_INET;
sin.sin_addr = ip->ip_dst;
blocked = 0;
idx = imo_match_group(imo, ifp,
(struct sockaddr *)&sin);
if (idx == -1) {
/*
* No group membership for this socket.
* Do not bump udps_noportbcast, as
* this will happen further down.
*/
blocked++;
} else {
/*
* Check for a multicast source filter
* entry on this socket for this group.
* MCAST_EXCLUDE is the default
* behaviour. It means default accept;
* entries, if present, denote sources
* to be excluded from delivery.
*/
ims = imo_match_source(imo, idx,
(struct sockaddr *)&udp_in);
mode = imo->imo_mfilters[idx].imf_fmode;
if ((ims != NULL &&
mode == MCAST_EXCLUDE) ||
(ims == NULL &&
mode == MCAST_INCLUDE)) {
#ifdef DIAGNOSTIC
if (bootverbose) {
printf("%s: blocked by"
" source filter\n",
__func__);
}
#endif
V_udpstat.udps_filtermcast++;
blocked++;
}
}
if (blocked != 0) {
INP_RUNLOCK(inp);
continue;
}
}
if (last != NULL) {
struct mbuf *n;
n = m_copy(m, 0, M_COPYALL);
if (last->inp_ppcb == NULL) {
if (n != NULL)
udp_append(last,
ip, n,
iphlen +
sizeof(struct udphdr),
&udp_in);
INP_RUNLOCK(last);
} else {
/*
* Engage the tunneling protocol we
* will have to leave the info_lock
* up, since we are hunting through
* multiple UDP's.
*
*/
udp_tun_func_t tunnel_func;
tunnel_func = (udp_tun_func_t)last->inp_ppcb;
tunnel_func(n, iphlen, last);
INP_RUNLOCK(last);
}
}
last = inp;
/*
* Don't look for additional matches if this one does
* not have either the SO_REUSEPORT or SO_REUSEADDR
* socket options set. This heuristic avoids
* searching through all pcbs in the common case of a
* non-shared port. It assumes that an application
* will never clear these options after setting them.
*/
if ((last->inp_socket->so_options &
(SO_REUSEPORT|SO_REUSEADDR)) == 0)
break;
}
if (last == NULL) {
/*
* No matching pcb found; discard datagram. (No need
* to send an ICMP Port Unreachable for a broadcast
* or multicast datgram.)
*/
V_udpstat.udps_noportbcast++;
goto badheadlocked;
}
if (last->inp_ppcb == NULL) {
udp_append(last, ip, m, iphlen + sizeof(struct udphdr),
&udp_in);
INP_RUNLOCK(last);
INP_INFO_RUNLOCK(&V_udbinfo);
} else {
/*
* Engage the tunneling protocol.
*/
udp_tun_func_t tunnel_func;
tunnel_func = (udp_tun_func_t)last->inp_ppcb;
tunnel_func(m, iphlen, last);
INP_RUNLOCK(last);
INP_INFO_RUNLOCK(&V_udbinfo);
}
return;
}
/*
* Locate pcb for datagram.
*/
inp = in_pcblookup_hash(&V_udbinfo, ip->ip_src, uh->uh_sport,
ip->ip_dst, uh->uh_dport, 1, ifp);
if (inp == NULL) {
if (udp_log_in_vain) {
char buf[4*sizeof "123"];
strcpy(buf, inet_ntoa(ip->ip_dst));
log(LOG_INFO,
"Connection attempt to UDP %s:%d from %s:%d\n",
buf, ntohs(uh->uh_dport), inet_ntoa(ip->ip_src),
ntohs(uh->uh_sport));
}
V_udpstat.udps_noport++;
if (m->m_flags & (M_BCAST | M_MCAST)) {
V_udpstat.udps_noportbcast++;
goto badheadlocked;
}
if (V_udp_blackhole)
goto badheadlocked;
if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0)
goto badheadlocked;
*ip = save_ip;
ip->ip_len += iphlen;
icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0);
INP_INFO_RUNLOCK(&V_udbinfo);
return;
}
/*
* Check the minimum TTL for socket.
*/
INP_RLOCK(inp);
INP_INFO_RUNLOCK(&V_udbinfo);
if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) {
INP_RUNLOCK(inp);
goto badunlocked;
}
if (inp->inp_ppcb != NULL) {
/*
* Engage the tunneling protocol.
*/
udp_tun_func_t tunnel_func;
tunnel_func = (udp_tun_func_t)inp->inp_ppcb;
tunnel_func(m, iphlen, inp);
INP_RUNLOCK(inp);
return;
}
udp_append(inp, ip, m, iphlen + sizeof(struct udphdr), &udp_in);
INP_RUNLOCK(inp);
return;
badheadlocked:
if (inp)
INP_RUNLOCK(inp);
INP_INFO_RUNLOCK(&V_udbinfo);
badunlocked:
m_freem(m);
}
/*
* Notify a udp user of an asynchronous error; just wake up so that they can
* collect error status.
*/
struct inpcb *
udp_notify(struct inpcb *inp, int errno)
{
/*
* While udp_ctlinput() always calls udp_notify() with a read lock
* when invoking it directly, in_pcbnotifyall() currently uses write
* locks due to sharing code with TCP. For now, accept either a read
* or a write lock, but a read lock is sufficient.
*/
INP_LOCK_ASSERT(inp);
inp->inp_socket->so_error = errno;
sorwakeup(inp->inp_socket);
sowwakeup(inp->inp_socket);
return (inp);
}
void
udp_ctlinput(int cmd, struct sockaddr *sa, void *vip)
{
INIT_VNET_INET(curvnet);
struct ip *ip = vip;
struct udphdr *uh;
struct in_addr faddr;
struct inpcb *inp;
faddr = ((struct sockaddr_in *)sa)->sin_addr;
if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY)
return;
/*
* Redirects don't need to be handled up here.
*/
if (PRC_IS_REDIRECT(cmd))
return;
/*
* Hostdead is ugly because it goes linearly through all PCBs.
*
* XXX: We never get this from ICMP, otherwise it makes an excellent
* DoS attack on machines with many connections.
*/
if (cmd == PRC_HOSTDEAD)
ip = NULL;
else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0)
return;
if (ip != NULL) {
uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2));
INP_INFO_RLOCK(&V_udbinfo);
inp = in_pcblookup_hash(&V_udbinfo, faddr, uh->uh_dport,
ip->ip_src, uh->uh_sport, 0, NULL);
if (inp != NULL) {
INP_RLOCK(inp);
if (inp->inp_socket != NULL) {
udp_notify(inp, inetctlerrmap[cmd]);
}
INP_RUNLOCK(inp);
}
INP_INFO_RUNLOCK(&V_udbinfo);
} else
in_pcbnotifyall(&V_udbinfo, faddr, inetctlerrmap[cmd],
udp_notify);
}
static int
udp_pcblist(SYSCTL_HANDLER_ARGS)
{
INIT_VNET_INET(curvnet);
int error, i, n;
struct inpcb *inp, **inp_list;
inp_gen_t gencnt;
struct xinpgen xig;
/*
* The process of preparing the PCB list is too time-consuming and
* resource-intensive to repeat twice on every request.
*/
if (req->oldptr == 0) {
n = V_udbinfo.ipi_count;
req->oldidx = 2 * (sizeof xig)
+ (n + n/8) * sizeof(struct xinpcb);
return (0);
}
if (req->newptr != 0)
return (EPERM);
/*
* OK, now we're committed to doing something.
*/
INP_INFO_RLOCK(&V_udbinfo);
gencnt = V_udbinfo.ipi_gencnt;
n = V_udbinfo.ipi_count;
INP_INFO_RUNLOCK(&V_udbinfo);
error = sysctl_wire_old_buffer(req, 2 * (sizeof xig)
+ n * sizeof(struct xinpcb));
if (error != 0)
return (error);
xig.xig_len = sizeof xig;
xig.xig_count = n;
xig.xig_gen = gencnt;
xig.xig_sogen = so_gencnt;
error = SYSCTL_OUT(req, &xig, sizeof xig);
if (error)
return (error);
inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK);
if (inp_list == 0)
return (ENOMEM);
INP_INFO_RLOCK(&V_udbinfo);
for (inp = LIST_FIRST(V_udbinfo.ipi_listhead), i = 0; inp && i < n;
inp = LIST_NEXT(inp, inp_list)) {
INP_RLOCK(inp);
if (inp->inp_gencnt <= gencnt &&
cr_canseeinpcb(req->td->td_ucred, inp) == 0)
inp_list[i++] = inp;
INP_RUNLOCK(inp);
}
INP_INFO_RUNLOCK(&V_udbinfo);
n = i;
error = 0;
for (i = 0; i < n; i++) {
inp = inp_list[i];
INP_RLOCK(inp);
if (inp->inp_gencnt <= gencnt) {
struct xinpcb xi;
bzero(&xi, sizeof(xi));
xi.xi_len = sizeof xi;
/* XXX should avoid extra copy */
bcopy(inp, &xi.xi_inp, sizeof *inp);
if (inp->inp_socket)
sotoxsocket(inp->inp_socket, &xi.xi_socket);
xi.xi_inp.inp_gencnt = inp->inp_gencnt;
INP_RUNLOCK(inp);
error = SYSCTL_OUT(req, &xi, sizeof xi);
} else
INP_RUNLOCK(inp);
}
if (!error) {
/*
* Give the user an updated idea of our state. If the
* generation differs from what we told her before, she knows
* that something happened while we were processing this
* request, and it might be necessary to retry.
*/
INP_INFO_RLOCK(&V_udbinfo);
xig.xig_gen = V_udbinfo.ipi_gencnt;
xig.xig_sogen = so_gencnt;
xig.xig_count = V_udbinfo.ipi_count;
INP_INFO_RUNLOCK(&V_udbinfo);
error = SYSCTL_OUT(req, &xig, sizeof xig);
}
free(inp_list, M_TEMP);
return (error);
}
SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist, CTLFLAG_RD, 0, 0,
udp_pcblist, "S,xinpcb", "List of active UDP sockets");
static int
udp_getcred(SYSCTL_HANDLER_ARGS)
{
INIT_VNET_INET(curvnet);
struct xucred xuc;
struct sockaddr_in addrs[2];
struct inpcb *inp;
int error;
error = priv_check(req->td, PRIV_NETINET_GETCRED);
if (error)
return (error);
error = SYSCTL_IN(req, addrs, sizeof(addrs));
if (error)
return (error);
INP_INFO_RLOCK(&V_udbinfo);
inp = in_pcblookup_hash(&V_udbinfo, addrs[1].sin_addr, addrs[1].sin_port,
addrs[0].sin_addr, addrs[0].sin_port, 1, NULL);
if (inp != NULL) {
INP_RLOCK(inp);
INP_INFO_RUNLOCK(&V_udbinfo);
if (inp->inp_socket == NULL)
error = ENOENT;
if (error == 0)
error = cr_canseeinpcb(req->td->td_ucred, inp);
if (error == 0)
cru2x(inp->inp_cred, &xuc);
INP_RUNLOCK(inp);
} else {
INP_INFO_RUNLOCK(&V_udbinfo);
error = ENOENT;
}
if (error == 0)
error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
return (error);
}
SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred,
CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0,
udp_getcred, "S,xucred", "Get the xucred of a UDP connection");
static int
udp_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr,
struct mbuf *control, struct thread *td)
{
INIT_VNET_INET(inp->inp_vnet);
struct udpiphdr *ui;
int len = m->m_pkthdr.len;
struct in_addr faddr, laddr;
struct cmsghdr *cm;
struct sockaddr_in *sin, src;
int error = 0;
int ipflags;
u_short fport, lport;
int unlock_udbinfo;
/*
* udp_output() may need to temporarily bind or connect the current
* inpcb. As such, we don't know up front whether we will need the
* pcbinfo lock or not. Do any work to decide what is needed up
* front before acquiring any locks.
*/
if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) {
if (control)
m_freem(control);
m_freem(m);
return (EMSGSIZE);
}
src.sin_family = 0;
if (control != NULL) {
/*
* XXX: Currently, we assume all the optional information is
* stored in a single mbuf.
*/
if (control->m_next) {
m_freem(control);
m_freem(m);
return (EINVAL);
}
for (; control->m_len > 0;
control->m_data += CMSG_ALIGN(cm->cmsg_len),
control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
cm = mtod(control, struct cmsghdr *);
if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0
|| cm->cmsg_len > control->m_len) {
error = EINVAL;
break;
}
if (cm->cmsg_level != IPPROTO_IP)
continue;
switch (cm->cmsg_type) {
case IP_SENDSRCADDR:
if (cm->cmsg_len !=
CMSG_LEN(sizeof(struct in_addr))) {
error = EINVAL;
break;
}
bzero(&src, sizeof(src));
src.sin_family = AF_INET;
src.sin_len = sizeof(src);
src.sin_port = inp->inp_lport;
src.sin_addr =
*(struct in_addr *)CMSG_DATA(cm);
break;
default:
error = ENOPROTOOPT;
break;
}
if (error)
break;
}
m_freem(control);
}
if (error) {
m_freem(m);
return (error);
}
/*
* Depending on whether or not the application has bound or connected
* the socket, we may have to do varying levels of work. The optimal
* case is for a connected UDP socket, as a global lock isn't
* required at all.
*
* In order to decide which we need, we require stability of the
* inpcb binding, which we ensure by acquiring a read lock on the
* inpcb. This doesn't strictly follow the lock order, so we play
* the trylock and retry game; note that we may end up with more
* conservative locks than required the second time around, so later
* assertions have to accept that. Further analysis of the number of
* misses under contention is required.
*/
sin = (struct sockaddr_in *)addr;
INP_RLOCK(inp);
if (sin != NULL &&
(inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0)) {
INP_RUNLOCK(inp);
INP_INFO_WLOCK(&V_udbinfo);
INP_WLOCK(inp);
unlock_udbinfo = 2;
} else if ((sin != NULL && (
(sin->sin_addr.s_addr == INADDR_ANY) ||
(sin->sin_addr.s_addr == INADDR_BROADCAST) ||
(inp->inp_laddr.s_addr == INADDR_ANY) ||
(inp->inp_lport == 0))) ||
(src.sin_family == AF_INET)) {
if (!INP_INFO_TRY_RLOCK(&V_udbinfo)) {
INP_RUNLOCK(inp);
INP_INFO_RLOCK(&V_udbinfo);
INP_RLOCK(inp);
}
unlock_udbinfo = 1;
} else
unlock_udbinfo = 0;
/*
* If the IP_SENDSRCADDR control message was specified, override the
* source address for this datagram. Its use is invalidated if the
* address thus specified is incomplete or clobbers other inpcbs.
*/
laddr = inp->inp_laddr;
lport = inp->inp_lport;
if (src.sin_family == AF_INET) {
INP_INFO_LOCK_ASSERT(&V_udbinfo);
if ((lport == 0) ||
(laddr.s_addr == INADDR_ANY &&
src.sin_addr.s_addr == INADDR_ANY)) {
error = EINVAL;
goto release;
}
error = in_pcbbind_setup(inp, (struct sockaddr *)&src,
&laddr.s_addr, &lport, td->td_ucred);
if (error)
goto release;
}
/*
* If a UDP socket has been connected, then a local address/port will
* have been selected and bound.
*
* If a UDP socket has not been connected to, then an explicit
* destination address must be used, in which case a local
* address/port may not have been selected and bound.
*/
if (sin != NULL) {
INP_LOCK_ASSERT(inp);
if (inp->inp_faddr.s_addr != INADDR_ANY) {
error = EISCONN;
goto release;
}
/*
* Jail may rewrite the destination address, so let it do
* that before we use it.
*/
error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
if (error)
goto release;
/*
* If a local address or port hasn't yet been selected, or if
* the destination address needs to be rewritten due to using
* a special INADDR_ constant, invoke in_pcbconnect_setup()
* to do the heavy lifting. Once a port is selected, we
* commit the binding back to the socket; we also commit the
* binding of the address if in jail.
*
* If we already have a valid binding and we're not
* requesting a destination address rewrite, use a fast path.
*/
if (inp->inp_laddr.s_addr == INADDR_ANY ||
inp->inp_lport == 0 ||
sin->sin_addr.s_addr == INADDR_ANY ||
sin->sin_addr.s_addr == INADDR_BROADCAST) {
INP_INFO_LOCK_ASSERT(&V_udbinfo);
error = in_pcbconnect_setup(inp, addr, &laddr.s_addr,
&lport, &faddr.s_addr, &fport, NULL,
td->td_ucred);
if (error)
goto release;
/*
* XXXRW: Why not commit the port if the address is
* !INADDR_ANY?
*/
/* Commit the local port if newly assigned. */
if (inp->inp_laddr.s_addr == INADDR_ANY &&
inp->inp_lport == 0) {
INP_INFO_WLOCK_ASSERT(&V_udbinfo);
INP_WLOCK_ASSERT(inp);
/*
* Remember addr if jailed, to prevent
* rebinding.
*/
if (jailed(td->td_ucred))
inp->inp_laddr = laddr;
inp->inp_lport = lport;
if (in_pcbinshash(inp) != 0) {
inp->inp_lport = 0;
error = EAGAIN;
goto release;
}
inp->inp_flags |= INP_ANONPORT;
}
} else {
faddr = sin->sin_addr;
fport = sin->sin_port;
}
} else {
INP_LOCK_ASSERT(inp);
faddr = inp->inp_faddr;
fport = inp->inp_fport;
if (faddr.s_addr == INADDR_ANY) {
error = ENOTCONN;
goto release;
}
}
/*
* Calculate data length and get a mbuf for UDP, IP, and possible
* link-layer headers. Immediate slide the data pointer back forward
* since we won't use that space at this layer.
*/
M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_DONTWAIT);
if (m == NULL) {
error = ENOBUFS;
goto release;
}
m->m_data += max_linkhdr;
m->m_len -= max_linkhdr;
m->m_pkthdr.len -= max_linkhdr;
/*
* Fill in mbuf with extended UDP header and addresses and length put
* into network format.
*/
ui = mtod(m, struct udpiphdr *);
bzero(ui->ui_x1, sizeof(ui->ui_x1)); /* XXX still needed? */
ui->ui_pr = IPPROTO_UDP;
ui->ui_src = laddr;
ui->ui_dst = faddr;
ui->ui_sport = lport;
ui->ui_dport = fport;
ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr));
/*
* Set the Don't Fragment bit in the IP header.
*/
if (inp->inp_flags & INP_DONTFRAG) {
struct ip *ip;
ip = (struct ip *)&ui->ui_i;
ip->ip_off |= IP_DF;
}
ipflags = 0;
if (inp->inp_socket->so_options & SO_DONTROUTE)
ipflags |= IP_ROUTETOIF;
if (inp->inp_socket->so_options & SO_BROADCAST)
ipflags |= IP_ALLOWBROADCAST;
if (inp->inp_flags & INP_ONESBCAST)
ipflags |= IP_SENDONES;
#ifdef MAC
mac_inpcb_create_mbuf(inp, m);
#endif
/*
* Set up checksum and output datagram.
*/
if (udp_cksum) {
if (inp->inp_flags & INP_ONESBCAST)
faddr.s_addr = INADDR_BROADCAST;
ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr,
htons((u_short)len + sizeof(struct udphdr) + IPPROTO_UDP));
m->m_pkthdr.csum_flags = CSUM_UDP;
m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
} else
ui->ui_sum = 0;
((struct ip *)ui)->ip_len = sizeof (struct udpiphdr) + len;
((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl; /* XXX */
((struct ip *)ui)->ip_tos = inp->inp_ip_tos; /* XXX */
V_udpstat.udps_opackets++;
if (unlock_udbinfo == 2)
INP_INFO_WUNLOCK(&V_udbinfo);
else if (unlock_udbinfo == 1)
INP_INFO_RUNLOCK(&V_udbinfo);
error = ip_output(m, inp->inp_options, NULL, ipflags,
inp->inp_moptions, inp);
if (unlock_udbinfo == 2)
INP_WUNLOCK(inp);
else
INP_RUNLOCK(inp);
return (error);
release:
if (unlock_udbinfo == 2) {
INP_WUNLOCK(inp);
INP_INFO_WUNLOCK(&V_udbinfo);
} else if (unlock_udbinfo == 1) {
INP_RUNLOCK(inp);
INP_INFO_RUNLOCK(&V_udbinfo);
} else
INP_RUNLOCK(inp);
m_freem(m);
return (error);
}
static void
udp_abort(struct socket *so)
{
INIT_VNET_INET(so->so_vnet);
struct inpcb *inp;
inp = sotoinpcb(so);
KASSERT(inp != NULL, ("udp_abort: inp == NULL"));
INP_INFO_WLOCK(&V_udbinfo);
INP_WLOCK(inp);
if (inp->inp_faddr.s_addr != INADDR_ANY) {
in_pcbdisconnect(inp);
inp->inp_laddr.s_addr = INADDR_ANY;
soisdisconnected(so);
}
INP_WUNLOCK(inp);
INP_INFO_WUNLOCK(&V_udbinfo);
}
static int
udp_attach(struct socket *so, int proto, struct thread *td)
{
INIT_VNET_INET(so->so_vnet);
struct inpcb *inp;
int error;
inp = sotoinpcb(so);
KASSERT(inp == NULL, ("udp_attach: inp != NULL"));
error = soreserve(so, udp_sendspace, udp_recvspace);
if (error)
return (error);
INP_INFO_WLOCK(&V_udbinfo);
error = in_pcballoc(so, &V_udbinfo);
if (error) {
INP_INFO_WUNLOCK(&V_udbinfo);
return (error);
}
inp = (struct inpcb *)so->so_pcb;
INP_INFO_WUNLOCK(&V_udbinfo);
inp->inp_vflag |= INP_IPV4;
inp->inp_ip_ttl = V_ip_defttl;
/*
* UDP does not have a per-protocol pcb (inp->inp_ppcb).
* We use this pointer for kernel tunneling pointer.
* If we ever need to have a protocol block we will
* need to move this function pointer there. Null
* in this pointer means "do the normal thing".
*/
inp->inp_ppcb = NULL;
INP_WUNLOCK(inp);
return (0);
}
int
udp_set_kernel_tunneling(struct socket *so, udp_tun_func_t f)
{
struct inpcb *inp;
inp = (struct inpcb *)so->so_pcb;
KASSERT(so->so_type == SOCK_DGRAM, ("udp_set_kernel_tunneling: !dgram"));
KASSERT(so->so_pcb != NULL, ("udp_set_kernel_tunneling: NULL inp"));
if (so->so_type != SOCK_DGRAM) {
/* Not UDP socket... sorry! */
return (ENOTSUP);
}
if (inp == NULL) {
/* NULL INP? */
return (EINVAL);
}
INP_WLOCK(inp);
if (inp->inp_ppcb != NULL) {
INP_WUNLOCK(inp);
return (EBUSY);
}
inp->inp_ppcb = f;
INP_WUNLOCK(inp);
return (0);
}
static int
udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
{
INIT_VNET_INET(so->so_vnet);
struct inpcb *inp;
int error;
inp = sotoinpcb(so);
KASSERT(inp != NULL, ("udp_bind: inp == NULL"));
INP_INFO_WLOCK(&V_udbinfo);
INP_WLOCK(inp);
error = in_pcbbind(inp, nam, td->td_ucred);
INP_WUNLOCK(inp);
INP_INFO_WUNLOCK(&V_udbinfo);
return (error);
}
static void
udp_close(struct socket *so)
{
INIT_VNET_INET(so->so_vnet);
struct inpcb *inp;
inp = sotoinpcb(so);
KASSERT(inp != NULL, ("udp_close: inp == NULL"));
INP_INFO_WLOCK(&V_udbinfo);
INP_WLOCK(inp);
if (inp->inp_faddr.s_addr != INADDR_ANY) {
in_pcbdisconnect(inp);
inp->inp_laddr.s_addr = INADDR_ANY;
soisdisconnected(so);
}
INP_WUNLOCK(inp);
INP_INFO_WUNLOCK(&V_udbinfo);
}
static int
udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
{
INIT_VNET_INET(so->so_vnet);
struct inpcb *inp;
int error;
struct sockaddr_in *sin;
inp = sotoinpcb(so);
KASSERT(inp != NULL, ("udp_connect: inp == NULL"));
INP_INFO_WLOCK(&V_udbinfo);
INP_WLOCK(inp);
if (inp->inp_faddr.s_addr != INADDR_ANY) {
INP_WUNLOCK(inp);
INP_INFO_WUNLOCK(&V_udbinfo);
return (EISCONN);
}
sin = (struct sockaddr_in *)nam;
error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
if (error != 0) {
INP_WUNLOCK(inp);
INP_INFO_WUNLOCK(&V_udbinfo);
return (error);
}
error = in_pcbconnect(inp, nam, td->td_ucred);
if (error == 0)
soisconnected(so);
INP_WUNLOCK(inp);
INP_INFO_WUNLOCK(&V_udbinfo);
return (error);
}
static void
udp_detach(struct socket *so)
{
INIT_VNET_INET(so->so_vnet);
struct inpcb *inp;
inp = sotoinpcb(so);
KASSERT(inp != NULL, ("udp_detach: inp == NULL"));
KASSERT(inp->inp_faddr.s_addr == INADDR_ANY,
("udp_detach: not disconnected"));
INP_INFO_WLOCK(&V_udbinfo);
INP_WLOCK(inp);
in_pcbdetach(inp);
in_pcbfree(inp);
INP_INFO_WUNLOCK(&V_udbinfo);
}
static int
udp_disconnect(struct socket *so)
{
INIT_VNET_INET(so->so_vnet);
struct inpcb *inp;
inp = sotoinpcb(so);
KASSERT(inp != NULL, ("udp_disconnect: inp == NULL"));
INP_INFO_WLOCK(&V_udbinfo);
INP_WLOCK(inp);
if (inp->inp_faddr.s_addr == INADDR_ANY) {
INP_WUNLOCK(inp);
INP_INFO_WUNLOCK(&V_udbinfo);
return (ENOTCONN);
}
in_pcbdisconnect(inp);
inp->inp_laddr.s_addr = INADDR_ANY;
SOCK_LOCK(so);
so->so_state &= ~SS_ISCONNECTED; /* XXX */
SOCK_UNLOCK(so);
INP_WUNLOCK(inp);
INP_INFO_WUNLOCK(&V_udbinfo);
return (0);
}
static int
udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,
struct mbuf *control, struct thread *td)
{
struct inpcb *inp;
inp = sotoinpcb(so);
KASSERT(inp != NULL, ("udp_send: inp == NULL"));
return (udp_output(inp, m, addr, control, td));
}
int
udp_shutdown(struct socket *so)
{
struct inpcb *inp;
inp = sotoinpcb(so);
KASSERT(inp != NULL, ("udp_shutdown: inp == NULL"));
INP_WLOCK(inp);
socantsendmore(so);
INP_WUNLOCK(inp);
return (0);
}
struct pr_usrreqs udp_usrreqs = {
.pru_abort = udp_abort,
.pru_attach = udp_attach,
.pru_bind = udp_bind,
.pru_connect = udp_connect,
.pru_control = in_control,
.pru_detach = udp_detach,
.pru_disconnect = udp_disconnect,
.pru_peeraddr = in_getpeeraddr,
.pru_send = udp_send,
.pru_soreceive = soreceive_dgram,
.pru_sosend = sosend_dgram,
.pru_shutdown = udp_shutdown,
.pru_sockaddr = in_getsockaddr,
.pru_sosetlabel = in_pcbsosetlabel,
.pru_close = udp_close,
};
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