Although originally socket was intended to use with ipfw(4) only, now it also can be used with pf(4). On a kernel without packet filters, it still can be used to inject traffic.
767 lines
20 KiB
C
767 lines
20 KiB
C
/*-
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* SPDX-License-Identifier: BSD-3-Clause
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*
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* Copyright (c) 1982, 1986, 1988, 1993
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* The Regents of the University of California. All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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#include <sys/cdefs.h>
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__FBSDID("$FreeBSD$");
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#include "opt_inet.h"
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#include "opt_inet6.h"
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#include "opt_sctp.h"
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#include <sys/param.h>
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#include <sys/eventhandler.h>
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#include <sys/kernel.h>
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#include <sys/lock.h>
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#include <sys/malloc.h>
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#include <sys/mbuf.h>
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#include <sys/module.h>
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#include <sys/kernel.h>
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#include <sys/priv.h>
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#include <sys/proc.h>
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#include <sys/domain.h>
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#include <sys/protosw.h>
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#include <sys/socket.h>
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#include <sys/socketvar.h>
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#include <sys/sysctl.h>
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#include <net/vnet.h>
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#include <net/if.h>
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#include <net/if_var.h>
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#include <net/netisr.h>
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#include <netinet/in.h>
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#include <netinet/in_pcb.h>
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#include <netinet/in_systm.h>
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#include <netinet/in_var.h>
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#include <netinet/ip.h>
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#include <netinet/ip_var.h>
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#include <netinet/ip_divert.h>
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#ifdef INET6
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#include <netinet/ip6.h>
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#include <netinet6/ip6_var.h>
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#endif
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#if defined(SCTP) || defined(SCTP_SUPPORT)
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#include <netinet/sctp_crc32.h>
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#endif
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#include <security/mac/mac_framework.h>
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/*
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* Divert sockets
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*/
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/*
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* Allocate enough space to hold a full IP packet
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*/
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#define DIVSNDQ (65536 + 100)
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#define DIVRCVQ (65536 + 100)
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/*
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* Usually a system has very few divert ports. Previous implementation
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* used a linked list.
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*/
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#define DIVHASHSIZE (1 << 3) /* 8 entries, one cache line. */
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#define DIVHASH(port) (port % DIVHASHSIZE)
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#define DCBHASH(dcb) ((dcb)->dcb_port % DIVHASHSIZE)
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/*
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* Divert sockets work in conjunction with ipfw or other packet filters,
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* see the divert(4) manpage for features.
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* Packets are selected by the packet filter and tagged with an
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* MTAG_IPFW_RULE tag carrying the 'divert port' number (as set by
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* the packet filter) and information on the matching filter rule for
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* subsequent reinjection. The divert_port is used to put the packet
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* on the corresponding divert socket, while the rule number is passed
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* up (at least partially) as the sin_port in the struct sockaddr.
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*
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* Packets written to the divert socket carry in sin_addr a
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* destination address, and in sin_port the number of the filter rule
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* after which to continue processing.
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* If the destination address is INADDR_ANY, the packet is treated as
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* as outgoing and sent to ip_output(); otherwise it is treated as
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* incoming and sent to ip_input().
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* Further, sin_zero carries some information on the interface,
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* which can be used in the reinject -- see comments in the code.
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*
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* On reinjection, processing in ip_input() and ip_output()
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* will be exactly the same as for the original packet, except that
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* packet filter processing will start at the rule number after the one
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* written in the sin_port (ipfw does not allow a rule #0, so sin_port=0
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* will apply the entire ruleset to the packet).
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*/
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static SYSCTL_NODE(_net_inet, OID_AUTO, divert, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
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"divert(4)");
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VNET_PCPUSTAT_DEFINE_STATIC(struct divstat, divstat);
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VNET_PCPUSTAT_SYSINIT(divstat);
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#ifdef VIMAGE
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VNET_PCPUSTAT_SYSUNINIT(divstat);
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#endif
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SYSCTL_VNET_PCPUSTAT(_net_inet_divert, OID_AUTO, stats, struct divstat,
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divstat, "divert(4) socket statistics");
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#define DIVSTAT_INC(name) \
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VNET_PCPUSTAT_ADD(struct divstat, divstat, div_ ## name, 1)
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static u_long div_sendspace = DIVSNDQ; /* XXX sysctl ? */
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static u_long div_recvspace = DIVRCVQ; /* XXX sysctl ? */
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static int div_output_inbound(int fmaily, struct socket *so, struct mbuf *m,
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struct sockaddr_in *sin);
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static int div_output_outbound(int family, struct socket *so, struct mbuf *m);
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struct divcb {
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union {
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SLIST_ENTRY(divcb) dcb_next;
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intptr_t dcb_bound;
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#define DCB_UNBOUND ((intptr_t)-1)
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};
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struct socket *dcb_socket;
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uint16_t dcb_port;
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uint64_t dcb_gencnt;
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struct epoch_context dcb_epochctx;
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};
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SLIST_HEAD(divhashhead, divcb);
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VNET_DEFINE_STATIC(struct divhashhead, divhash[DIVHASHSIZE]) = {};
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#define V_divhash VNET(divhash)
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VNET_DEFINE_STATIC(uint64_t, dcb_count) = 0;
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#define V_dcb_count VNET(dcb_count)
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VNET_DEFINE_STATIC(uint64_t, dcb_gencnt) = 0;
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#define V_dcb_gencnt VNET(dcb_gencnt)
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static struct mtx divert_mtx;
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MTX_SYSINIT(divert, &divert_mtx, "divert(4) socket pcb lists", MTX_DEF);
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#define DIVERT_LOCK() mtx_lock(&divert_mtx)
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#define DIVERT_UNLOCK() mtx_unlock(&divert_mtx)
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/*
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* Divert a packet by passing it up to the divert socket at port 'port'.
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*/
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static void
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divert_packet(struct mbuf *m, bool incoming)
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{
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struct divcb *dcb;
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u_int16_t nport;
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struct sockaddr_in divsrc;
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struct m_tag *mtag;
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NET_EPOCH_ASSERT();
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mtag = m_tag_locate(m, MTAG_IPFW_RULE, 0, NULL);
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if (mtag == NULL) {
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m_freem(m);
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return;
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}
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/* Assure header */
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if (m->m_len < sizeof(struct ip) &&
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(m = m_pullup(m, sizeof(struct ip))) == NULL)
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return;
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#ifdef INET
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/* Delayed checksums are currently not compatible with divert. */
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if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
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in_delayed_cksum(m);
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m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
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}
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#if defined(SCTP) || defined(SCTP_SUPPORT)
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if (m->m_pkthdr.csum_flags & CSUM_SCTP) {
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struct ip *ip;
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ip = mtod(m, struct ip *);
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sctp_delayed_cksum(m, (uint32_t)(ip->ip_hl << 2));
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m->m_pkthdr.csum_flags &= ~CSUM_SCTP;
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}
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#endif
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#endif
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#ifdef INET6
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if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
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in6_delayed_cksum(m, m->m_pkthdr.len -
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sizeof(struct ip6_hdr), sizeof(struct ip6_hdr));
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m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA_IPV6;
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}
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#if defined(SCTP) || defined(SCTP_SUPPORT)
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if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6) {
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sctp_delayed_cksum(m, sizeof(struct ip6_hdr));
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m->m_pkthdr.csum_flags &= ~CSUM_SCTP_IPV6;
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}
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#endif
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#endif /* INET6 */
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bzero(&divsrc, sizeof(divsrc));
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divsrc.sin_len = sizeof(divsrc);
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divsrc.sin_family = AF_INET;
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/* record matching rule, in host format */
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divsrc.sin_port = ((struct ipfw_rule_ref *)(mtag+1))->rulenum;
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/*
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* Record receive interface address, if any.
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* But only for incoming packets.
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*/
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if (incoming) {
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struct ifaddr *ifa;
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struct ifnet *ifp;
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/* Sanity check */
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M_ASSERTPKTHDR(m);
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/* Find IP address for receive interface */
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ifp = m->m_pkthdr.rcvif;
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CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
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if (ifa->ifa_addr->sa_family != AF_INET)
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continue;
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divsrc.sin_addr =
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((struct sockaddr_in *) ifa->ifa_addr)->sin_addr;
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break;
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}
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}
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/*
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* Record the incoming interface name whenever we have one.
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*/
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if (m->m_pkthdr.rcvif) {
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/*
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* Hide the actual interface name in there in the
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* sin_zero array. XXX This needs to be moved to a
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* different sockaddr type for divert, e.g.
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* sockaddr_div with multiple fields like
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* sockaddr_dl. Presently we have only 7 bytes
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* but that will do for now as most interfaces
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* are 4 or less + 2 or less bytes for unit.
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* There is probably a faster way of doing this,
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* possibly taking it from the sockaddr_dl on the iface.
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* This solves the problem of a P2P link and a LAN interface
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* having the same address, which can result in the wrong
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* interface being assigned to the packet when fed back
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* into the divert socket. Theoretically if the daemon saves
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* and re-uses the sockaddr_in as suggested in the man pages,
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* this iface name will come along for the ride.
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* (see div_output for the other half of this.)
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*/
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strlcpy(divsrc.sin_zero, m->m_pkthdr.rcvif->if_xname,
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sizeof(divsrc.sin_zero));
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}
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/* Put packet on socket queue, if any */
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nport = htons((uint16_t)(((struct ipfw_rule_ref *)(mtag+1))->info));
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SLIST_FOREACH(dcb, &V_divhash[DIVHASH(nport)], dcb_next)
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if (dcb->dcb_port == nport)
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break;
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if (dcb != NULL) {
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struct socket *sa = dcb->dcb_socket;
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SOCKBUF_LOCK(&sa->so_rcv);
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if (sbappendaddr_locked(&sa->so_rcv,
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(struct sockaddr *)&divsrc, m, NULL) == 0) {
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soroverflow_locked(sa);
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m_freem(m);
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} else {
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sorwakeup_locked(sa);
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DIVSTAT_INC(diverted);
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}
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} else {
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DIVSTAT_INC(noport);
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m_freem(m);
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}
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}
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/*
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* Deliver packet back into the IP processing machinery.
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*
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* If no address specified, or address is 0.0.0.0, send to ip_output();
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* otherwise, send to ip_input() and mark as having been received on
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* the interface with that address.
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*/
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static int
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div_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam,
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struct mbuf *control, struct thread *td)
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{
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struct epoch_tracker et;
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struct sockaddr_in *sin = (struct sockaddr_in *)nam;
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const struct ip *ip;
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struct m_tag *mtag;
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struct ipfw_rule_ref *dt;
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int error, family;
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if (control)
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m_freem(control);
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/* Packet must have a header (but that's about it) */
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if (m->m_len < sizeof (struct ip) &&
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(m = m_pullup(m, sizeof (struct ip))) == NULL) {
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m_freem(m);
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return (EINVAL);
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}
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if (sin != NULL) {
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if (sin->sin_family != AF_INET) {
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m_freem(m);
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return (EAFNOSUPPORT);
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}
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if (sin->sin_len != sizeof(*sin)) {
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m_freem(m);
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return (EINVAL);
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}
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}
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/*
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* An mbuf may hasn't come from userland, but we pretend
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* that it has.
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*/
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m->m_pkthdr.rcvif = NULL;
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m->m_nextpkt = NULL;
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M_SETFIB(m, so->so_fibnum);
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mtag = m_tag_locate(m, MTAG_IPFW_RULE, 0, NULL);
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if (mtag == NULL) {
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/* this should be normal */
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mtag = m_tag_alloc(MTAG_IPFW_RULE, 0,
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sizeof(struct ipfw_rule_ref), M_NOWAIT | M_ZERO);
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if (mtag == NULL) {
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m_freem(m);
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return (ENOBUFS);
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}
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m_tag_prepend(m, mtag);
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}
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dt = (struct ipfw_rule_ref *)(mtag+1);
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/* Loopback avoidance and state recovery */
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if (sin) {
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int i;
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/* set the starting point. We provide a non-zero slot,
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* but a non_matching chain_id to skip that info and use
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* the rulenum/rule_id.
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*/
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dt->slot = 1; /* dummy, chain_id is invalid */
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dt->chain_id = 0;
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dt->rulenum = sin->sin_port+1; /* host format ? */
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dt->rule_id = 0;
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/* XXX: broken for IPv6 */
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/*
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* Find receive interface with the given name, stuffed
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* (if it exists) in the sin_zero[] field.
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* The name is user supplied data so don't trust its size
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* or that it is zero terminated.
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*/
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for (i = 0; i < sizeof(sin->sin_zero) && sin->sin_zero[i]; i++)
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;
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if ( i > 0 && i < sizeof(sin->sin_zero))
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m->m_pkthdr.rcvif = ifunit(sin->sin_zero);
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}
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ip = mtod(m, struct ip *);
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switch (ip->ip_v) {
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#ifdef INET
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case IPVERSION:
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family = AF_INET;
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break;
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#endif
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#ifdef INET6
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case IPV6_VERSION >> 4:
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family = AF_INET6;
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break;
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#endif
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default:
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m_freem(m);
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return (EAFNOSUPPORT);
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}
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/* Reinject packet into the system as incoming or outgoing */
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NET_EPOCH_ENTER(et);
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if (!sin || sin->sin_addr.s_addr == 0) {
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dt->info |= IPFW_IS_DIVERT | IPFW_INFO_OUT;
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error = div_output_outbound(family, so, m);
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} else {
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dt->info |= IPFW_IS_DIVERT | IPFW_INFO_IN;
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error = div_output_inbound(family, so, m, sin);
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}
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NET_EPOCH_EXIT(et);
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return (error);
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}
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/*
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* Sends mbuf @m to the wire via ip[6]_output().
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*
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* Returns 0 on success or an errno value on failure. @m is always consumed.
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*/
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static int
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div_output_outbound(int family, struct socket *so, struct mbuf *m)
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{
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int error;
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switch (family) {
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#ifdef INET
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case AF_INET:
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{
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struct ip *const ip = mtod(m, struct ip *);
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/* Don't allow packet length sizes that will crash. */
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if (((u_short)ntohs(ip->ip_len) > m->m_pkthdr.len)) {
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m_freem(m);
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return (EINVAL);
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}
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break;
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}
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#endif
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#ifdef INET6
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case AF_INET6:
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{
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struct ip6_hdr *const ip6 = mtod(m, struct ip6_hdr *);
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/* Don't allow packet length sizes that will crash */
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if (((u_short)ntohs(ip6->ip6_plen) > m->m_pkthdr.len)) {
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m_freem(m);
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return (EINVAL);
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}
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break;
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}
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#endif
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}
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#ifdef MAC
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mac_socket_create_mbuf(so, m);
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#endif
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error = 0;
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switch (family) {
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#ifdef INET
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case AF_INET:
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error = ip_output(m, NULL, NULL,
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((so->so_options & SO_DONTROUTE) ? IP_ROUTETOIF : 0)
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| IP_ALLOWBROADCAST | IP_RAWOUTPUT, NULL, NULL);
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break;
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#endif
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#ifdef INET6
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case AF_INET6:
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error = ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL);
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break;
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#endif
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}
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if (error == 0)
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DIVSTAT_INC(outbound);
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return (error);
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}
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/*
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* Schedules mbuf @m for local processing via IPv4/IPv6 netisr queue.
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*
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* Returns 0 on success or an errno value on failure. @m is always consumed.
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*/
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static int
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div_output_inbound(int family, struct socket *so, struct mbuf *m,
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struct sockaddr_in *sin)
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{
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struct ifaddr *ifa;
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if (m->m_pkthdr.rcvif == NULL) {
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/*
|
|
* No luck with the name, check by IP address.
|
|
* Clear the port and the ifname to make sure
|
|
* there are no distractions for ifa_ifwithaddr.
|
|
*/
|
|
|
|
/* XXX: broken for IPv6 */
|
|
bzero(sin->sin_zero, sizeof(sin->sin_zero));
|
|
sin->sin_port = 0;
|
|
ifa = ifa_ifwithaddr((struct sockaddr *) sin);
|
|
if (ifa == NULL) {
|
|
m_freem(m);
|
|
return (EADDRNOTAVAIL);
|
|
}
|
|
m->m_pkthdr.rcvif = ifa->ifa_ifp;
|
|
}
|
|
#ifdef MAC
|
|
mac_socket_create_mbuf(so, m);
|
|
#endif
|
|
/* Send packet to input processing via netisr */
|
|
switch (family) {
|
|
#ifdef INET
|
|
case AF_INET:
|
|
{
|
|
const struct ip *ip;
|
|
|
|
ip = mtod(m, struct ip *);
|
|
/*
|
|
* Restore M_BCAST flag when destination address is
|
|
* broadcast. It is expected by ip_tryforward().
|
|
*/
|
|
if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)))
|
|
m->m_flags |= M_MCAST;
|
|
else if (in_broadcast(ip->ip_dst, m->m_pkthdr.rcvif))
|
|
m->m_flags |= M_BCAST;
|
|
netisr_queue_src(NETISR_IP, (uintptr_t)so, m);
|
|
DIVSTAT_INC(inbound);
|
|
break;
|
|
}
|
|
#endif
|
|
#ifdef INET6
|
|
case AF_INET6:
|
|
netisr_queue_src(NETISR_IPV6, (uintptr_t)so, m);
|
|
DIVSTAT_INC(inbound);
|
|
break;
|
|
#endif
|
|
default:
|
|
m_freem(m);
|
|
return (EINVAL);
|
|
}
|
|
|
|
return (0);
|
|
}
|
|
|
|
static int
|
|
div_attach(struct socket *so, int proto, struct thread *td)
|
|
{
|
|
struct divcb *dcb;
|
|
int error;
|
|
|
|
if (td != NULL) {
|
|
error = priv_check(td, PRIV_NETINET_DIVERT);
|
|
if (error)
|
|
return (error);
|
|
}
|
|
error = soreserve(so, div_sendspace, div_recvspace);
|
|
if (error)
|
|
return error;
|
|
dcb = malloc(sizeof(*dcb), M_PCB, M_WAITOK);
|
|
dcb->dcb_bound = DCB_UNBOUND;
|
|
dcb->dcb_socket = so;
|
|
DIVERT_LOCK();
|
|
V_dcb_count++;
|
|
dcb->dcb_gencnt = ++V_dcb_gencnt;
|
|
DIVERT_UNLOCK();
|
|
so->so_pcb = dcb;
|
|
|
|
return (0);
|
|
}
|
|
|
|
static void
|
|
div_free(epoch_context_t ctx)
|
|
{
|
|
struct divcb *dcb = __containerof(ctx, struct divcb, dcb_epochctx);
|
|
|
|
free(dcb, M_PCB);
|
|
}
|
|
|
|
static void
|
|
div_detach(struct socket *so)
|
|
{
|
|
struct divcb *dcb = so->so_pcb;
|
|
|
|
so->so_pcb = NULL;
|
|
DIVERT_LOCK();
|
|
if (dcb->dcb_bound != DCB_UNBOUND)
|
|
SLIST_REMOVE(&V_divhash[DCBHASH(dcb)], dcb, divcb, dcb_next);
|
|
V_dcb_count--;
|
|
V_dcb_gencnt++;
|
|
DIVERT_UNLOCK();
|
|
NET_EPOCH_CALL(div_free, &dcb->dcb_epochctx);
|
|
}
|
|
|
|
static int
|
|
div_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
|
|
{
|
|
struct divcb *dcb;
|
|
uint16_t port;
|
|
|
|
if (nam->sa_family != AF_INET)
|
|
return EAFNOSUPPORT;
|
|
if (nam->sa_len != sizeof(struct sockaddr_in))
|
|
return EINVAL;
|
|
port = ((struct sockaddr_in *)nam)->sin_port;
|
|
DIVERT_LOCK();
|
|
SLIST_FOREACH(dcb, &V_divhash[DIVHASH(port)], dcb_next)
|
|
if (dcb->dcb_port == port) {
|
|
DIVERT_UNLOCK();
|
|
return (EADDRINUSE);
|
|
}
|
|
dcb = so->so_pcb;
|
|
if (dcb->dcb_bound != DCB_UNBOUND)
|
|
SLIST_REMOVE(&V_divhash[DCBHASH(dcb)], dcb, divcb, dcb_next);
|
|
dcb->dcb_port = port;
|
|
SLIST_INSERT_HEAD(&V_divhash[DIVHASH(port)], dcb, dcb_next);
|
|
DIVERT_UNLOCK();
|
|
|
|
return (0);
|
|
}
|
|
|
|
static int
|
|
div_shutdown(struct socket *so)
|
|
{
|
|
|
|
socantsendmore(so);
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
div_pcblist(SYSCTL_HANDLER_ARGS)
|
|
{
|
|
struct xinpgen xig;
|
|
struct divcb *dcb;
|
|
int error;
|
|
|
|
if (req->newptr != 0)
|
|
return EPERM;
|
|
|
|
if (req->oldptr == 0) {
|
|
u_int n;
|
|
|
|
n = V_dcb_count;
|
|
n += imax(n / 8, 10);
|
|
req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xinpcb);
|
|
return 0;
|
|
}
|
|
|
|
if ((error = sysctl_wire_old_buffer(req, 0)) != 0)
|
|
return (error);
|
|
|
|
bzero(&xig, sizeof(xig));
|
|
xig.xig_len = sizeof xig;
|
|
xig.xig_count = V_dcb_count;
|
|
xig.xig_gen = V_dcb_gencnt;
|
|
xig.xig_sogen = so_gencnt;
|
|
error = SYSCTL_OUT(req, &xig, sizeof xig);
|
|
if (error)
|
|
return error;
|
|
|
|
DIVERT_LOCK();
|
|
for (int i = 0; i < DIVHASHSIZE; i++)
|
|
SLIST_FOREACH(dcb, &V_divhash[i], dcb_next) {
|
|
if (dcb->dcb_gencnt <= xig.xig_gen) {
|
|
struct xinpcb xi;
|
|
|
|
bzero(&xi, sizeof(xi));
|
|
xi.xi_len = sizeof(struct xinpcb);
|
|
sotoxsocket(dcb->dcb_socket, &xi.xi_socket);
|
|
xi.inp_gencnt = dcb->dcb_gencnt;
|
|
xi.inp_vflag = INP_IPV4; /* XXX: netstat(1) */
|
|
xi.inp_inc.inc_ie.ie_lport = dcb->dcb_port;
|
|
error = SYSCTL_OUT(req, &xi, sizeof xi);
|
|
if (error)
|
|
goto errout;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
xig.xig_gen = V_dcb_gencnt;
|
|
xig.xig_sogen = so_gencnt;
|
|
xig.xig_count = V_dcb_count;
|
|
error = SYSCTL_OUT(req, &xig, sizeof xig);
|
|
|
|
errout:
|
|
DIVERT_UNLOCK();
|
|
|
|
return (error);
|
|
}
|
|
SYSCTL_PROC(_net_inet_divert, OID_AUTO, pcblist,
|
|
CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0, div_pcblist,
|
|
"S,xinpcb", "List of active divert sockets");
|
|
|
|
static struct protosw div_protosw = {
|
|
.pr_type = SOCK_RAW,
|
|
.pr_flags = PR_ATOMIC|PR_ADDR,
|
|
.pr_attach = div_attach,
|
|
.pr_bind = div_bind,
|
|
.pr_detach = div_detach,
|
|
.pr_send = div_send,
|
|
.pr_shutdown = div_shutdown,
|
|
};
|
|
|
|
static struct domain divertdomain = {
|
|
.dom_family = PF_DIVERT,
|
|
.dom_name = "divert",
|
|
.dom_nprotosw = 1,
|
|
.dom_protosw = { &div_protosw },
|
|
};
|
|
|
|
static int
|
|
div_modevent(module_t mod, int type, void *unused)
|
|
{
|
|
int err = 0;
|
|
|
|
switch (type) {
|
|
case MOD_LOAD:
|
|
domain_add(&divertdomain);
|
|
ip_divert_ptr = divert_packet;
|
|
break;
|
|
case MOD_QUIESCE:
|
|
/*
|
|
* IPDIVERT may normally not be unloaded because of the
|
|
* potential race conditions. Tell kldunload we can't be
|
|
* unloaded unless the unload is forced.
|
|
*/
|
|
err = EPERM;
|
|
break;
|
|
case MOD_UNLOAD:
|
|
/*
|
|
* Forced unload.
|
|
*
|
|
* Module ipdivert can only be unloaded if no sockets are
|
|
* connected. Maybe this can be changed later to forcefully
|
|
* disconnect any open sockets.
|
|
*
|
|
* XXXRW: Note that there is a slight race here, as a new
|
|
* socket open request could be spinning on the lock and then
|
|
* we destroy the lock.
|
|
*
|
|
* XXXGL: One more reason this code is incorrect is that it
|
|
* checks only the current vnet.
|
|
*/
|
|
DIVERT_LOCK();
|
|
if (V_dcb_count != 0) {
|
|
DIVERT_UNLOCK();
|
|
err = EBUSY;
|
|
break;
|
|
}
|
|
DIVERT_UNLOCK();
|
|
ip_divert_ptr = NULL;
|
|
domain_remove(&divertdomain);
|
|
break;
|
|
default:
|
|
err = EOPNOTSUPP;
|
|
break;
|
|
}
|
|
return err;
|
|
}
|
|
|
|
static moduledata_t ipdivertmod = {
|
|
"ipdivert",
|
|
div_modevent,
|
|
0
|
|
};
|
|
|
|
DECLARE_MODULE(ipdivert, ipdivertmod, SI_SUB_PROTO_FIREWALL, SI_ORDER_ANY);
|
|
MODULE_VERSION(ipdivert, 1);
|