diff options
Diffstat (limited to 'sys/netinet/ipfw/ip_fw_pfil.c')
-rw-r--r-- | sys/netinet/ipfw/ip_fw_pfil.c | 588 |
1 files changed, 0 insertions, 588 deletions
diff --git a/sys/netinet/ipfw/ip_fw_pfil.c b/sys/netinet/ipfw/ip_fw_pfil.c deleted file mode 100644 index 8d429e7..0000000 --- a/sys/netinet/ipfw/ip_fw_pfil.c +++ /dev/null @@ -1,588 +0,0 @@ -/*- - * Copyright (c) 2004 Andre Oppermann, Internet Business Solutions AG - * 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. - * - * 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. - */ - -#include <sys/cdefs.h> -__FBSDID("$FreeBSD$"); - -#include "opt_ipfw.h" -#include "opt_inet.h" -#include "opt_inet6.h" -#ifndef INET -#error IPFIREWALL requires INET. -#endif /* INET */ - -#include <sys/param.h> -#include <sys/systm.h> -#include <sys/malloc.h> -#include <sys/mbuf.h> -#include <sys/module.h> -#include <sys/kernel.h> -#include <sys/lock.h> -#include <sys/rwlock.h> -#include <sys/socket.h> -#include <sys/sysctl.h> - -#include <net/if.h> -#include <net/route.h> -#include <net/ethernet.h> -#include <net/pfil.h> -#include <net/vnet.h> - -#include <netinet/in.h> -#include <netinet/in_systm.h> -#include <netinet/ip.h> -#include <netinet/ip_var.h> -#include <netinet/ip_fw.h> -#ifdef INET6 -#include <netinet/ip6.h> -#include <netinet6/ip6_var.h> -#endif -#include <netinet/ipfw/ip_fw_private.h> -#include <netgraph/ng_ipfw.h> - -#include <machine/in_cksum.h> - -static VNET_DEFINE(int, fw_enable) = 1; -#define V_fw_enable VNET(fw_enable) - -#ifdef INET6 -static VNET_DEFINE(int, fw6_enable) = 1; -#define V_fw6_enable VNET(fw6_enable) -#endif - -static VNET_DEFINE(int, fwlink_enable) = 0; -#define V_fwlink_enable VNET(fwlink_enable) - -int ipfw_chg_hook(SYSCTL_HANDLER_ARGS); - -/* Forward declarations. */ -static int ipfw_divert(struct mbuf **, int, struct ipfw_rule_ref *, int); -static int ipfw_check_packet(void *, struct mbuf **, struct ifnet *, int, - struct inpcb *); -static int ipfw_check_frame(void *, struct mbuf **, struct ifnet *, int, - struct inpcb *); - -#ifdef SYSCTL_NODE - -SYSBEGIN(f1) - -SYSCTL_DECL(_net_inet_ip_fw); -SYSCTL_VNET_PROC(_net_inet_ip_fw, OID_AUTO, enable, - CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE3, &VNET_NAME(fw_enable), 0, - ipfw_chg_hook, "I", "Enable ipfw"); -#ifdef INET6 -SYSCTL_DECL(_net_inet6_ip6_fw); -SYSCTL_VNET_PROC(_net_inet6_ip6_fw, OID_AUTO, enable, - CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE3, &VNET_NAME(fw6_enable), 0, - ipfw_chg_hook, "I", "Enable ipfw+6"); -#endif /* INET6 */ - -SYSCTL_DECL(_net_link_ether); -SYSCTL_VNET_PROC(_net_link_ether, OID_AUTO, ipfw, - CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE3, &VNET_NAME(fwlink_enable), 0, - ipfw_chg_hook, "I", "Pass ether pkts through firewall"); - -SYSEND - -#endif /* SYSCTL_NODE */ - -/* - * The pfilter hook to pass packets to ipfw_chk and then to - * dummynet, divert, netgraph or other modules. - * The packet may be consumed. - */ -static int -ipfw_check_packet(void *arg, struct mbuf **m0, struct ifnet *ifp, int dir, - struct inpcb *inp) -{ - struct ip_fw_args args; - struct m_tag *tag; - int ipfw; - int ret; - - /* all the processing now uses ip_len in net format */ - if (mtod(*m0, struct ip *)->ip_v == 4) - SET_NET_IPLEN(mtod(*m0, struct ip *)); - - /* convert dir to IPFW values */ - dir = (dir == PFIL_IN) ? DIR_IN : DIR_OUT; - bzero(&args, sizeof(args)); - -again: - /* - * extract and remove the tag if present. If we are left - * with onepass, optimize the outgoing path. - */ - tag = m_tag_locate(*m0, MTAG_IPFW_RULE, 0, NULL); - if (tag != NULL) { - args.rule = *((struct ipfw_rule_ref *)(tag+1)); - m_tag_delete(*m0, tag); - if (args.rule.info & IPFW_ONEPASS) { - if (mtod(*m0, struct ip *)->ip_v == 4) - SET_HOST_IPLEN(mtod(*m0, struct ip *)); - return (0); - } - } - - args.m = *m0; - args.oif = dir == DIR_OUT ? ifp : NULL; - args.inp = inp; - - ipfw = ipfw_chk(&args); - *m0 = args.m; - - KASSERT(*m0 != NULL || ipfw == IP_FW_DENY, ("%s: m0 is NULL", - __func__)); - - /* breaking out of the switch means drop */ - ret = 0; /* default return value for pass */ - switch (ipfw) { - case IP_FW_PASS: - /* next_hop may be set by ipfw_chk */ - if (args.next_hop == NULL && args.next_hop6 == NULL) - break; /* pass */ -#if !defined(IPFIREWALL_FORWARD) || (!defined(INET6) && !defined(INET)) - ret = EACCES; -#else - { - struct m_tag *fwd_tag; - size_t len; - - KASSERT(args.next_hop == NULL || args.next_hop6 == NULL, - ("%s: both next_hop=%p and next_hop6=%p not NULL", __func__, - args.next_hop, args.next_hop6)); -#ifdef INET6 - if (args.next_hop6 != NULL) - len = sizeof(struct sockaddr_in6); -#endif -#ifdef INET - if (args.next_hop != NULL) - len = sizeof(struct sockaddr_in); -#endif - - /* Incoming packets should not be tagged so we do not - * m_tag_find. Outgoing packets may be tagged, so we - * reuse the tag if present. - */ - fwd_tag = (dir == DIR_IN) ? NULL : - m_tag_find(*m0, PACKET_TAG_IPFORWARD, NULL); - if (fwd_tag != NULL) { - m_tag_unlink(*m0, fwd_tag); - } else { - fwd_tag = m_tag_get(PACKET_TAG_IPFORWARD, len, - M_NOWAIT); - if (fwd_tag == NULL) { - ret = EACCES; - break; /* i.e. drop */ - } - } -#ifdef INET6 - if (args.next_hop6 != NULL) { - bcopy(args.next_hop6, (fwd_tag+1), len); - if (in6_localip(&args.next_hop6->sin6_addr)) - (*m0)->m_flags |= M_FASTFWD_OURS; - } -#endif -#ifdef INET - if (args.next_hop != NULL) { - bcopy(args.next_hop, (fwd_tag+1), len); - if (in_localip(args.next_hop->sin_addr)) - (*m0)->m_flags |= M_FASTFWD_OURS; - } -#endif - m_tag_prepend(*m0, fwd_tag); - } -#endif /* IPFIREWALL_FORWARD */ - break; - - case IP_FW_DENY: - ret = EACCES; - break; /* i.e. drop */ - - case IP_FW_DUMMYNET: - ret = EACCES; - if (ip_dn_io_ptr == NULL) - break; /* i.e. drop */ - if (mtod(*m0, struct ip *)->ip_v == 4) - ret = ip_dn_io_ptr(m0, dir, &args); - else if (mtod(*m0, struct ip *)->ip_v == 6) - ret = ip_dn_io_ptr(m0, dir | PROTO_IPV6, &args); - else - break; /* drop it */ - /* - * XXX should read the return value. - * dummynet normally eats the packet and sets *m0=NULL - * unless the packet can be sent immediately. In this - * case args is updated and we should re-run the - * check without clearing args. - */ - if (*m0 != NULL) - goto again; - break; - - case IP_FW_TEE: - case IP_FW_DIVERT: - if (ip_divert_ptr == NULL) { - ret = EACCES; - break; /* i.e. drop */ - } - ret = ipfw_divert(m0, dir, &args.rule, - (ipfw == IP_FW_TEE) ? 1 : 0); - /* continue processing for the original packet (tee). */ - if (*m0) - goto again; - break; - - case IP_FW_NGTEE: - case IP_FW_NETGRAPH: - if (ng_ipfw_input_p == NULL) { - ret = EACCES; - break; /* i.e. drop */ - } - ret = ng_ipfw_input_p(m0, dir, &args, - (ipfw == IP_FW_NGTEE) ? 1 : 0); - if (ipfw == IP_FW_NGTEE) /* ignore errors for NGTEE */ - goto again; /* continue with packet */ - break; - - case IP_FW_NAT: - /* honor one-pass in case of successful nat */ - if (V_fw_one_pass) - break; /* ret is already 0 */ - goto again; - - case IP_FW_REASS: - goto again; /* continue with packet */ - - default: - KASSERT(0, ("%s: unknown retval", __func__)); - } - - if (ret != 0) { - if (*m0) - FREE_PKT(*m0); - *m0 = NULL; - } - if (*m0 && mtod(*m0, struct ip *)->ip_v == 4) - SET_HOST_IPLEN(mtod(*m0, struct ip *)); - return ret; -} - -/* - * ipfw processing for ethernet packets (in and out). - * Inteface is NULL from ether_demux, and ifp from - * ether_output_frame. - */ -static int -ipfw_check_frame(void *arg, struct mbuf **m0, struct ifnet *dst, int dir, - struct inpcb *inp) -{ - struct ether_header *eh; - struct ether_header save_eh; - struct mbuf *m; - int i, ret; - struct ip_fw_args args; - struct m_tag *mtag; - - /* fetch start point from rule, if any */ - mtag = m_tag_locate(*m0, MTAG_IPFW_RULE, 0, NULL); - if (mtag == NULL) { - args.rule.slot = 0; - } else { - /* dummynet packet, already partially processed */ - struct ipfw_rule_ref *r; - - /* XXX can we free it after use ? */ - mtag->m_tag_id = PACKET_TAG_NONE; - r = (struct ipfw_rule_ref *)(mtag + 1); - if (r->info & IPFW_ONEPASS) - return (0); - args.rule = *r; - } - - /* I need some amt of data to be contiguous */ - m = *m0; - i = min(m->m_pkthdr.len, max_protohdr); - if (m->m_len < i) { - m = m_pullup(m, i); - if (m == NULL) { - *m0 = m; - return (0); - } - } - eh = mtod(m, struct ether_header *); - save_eh = *eh; /* save copy for restore below */ - m_adj(m, ETHER_HDR_LEN); /* strip ethernet header */ - - args.m = m; /* the packet we are looking at */ - args.oif = dst; /* destination, if any */ - args.next_hop = NULL; /* we do not support forward yet */ - args.next_hop6 = NULL; /* we do not support forward yet */ - args.eh = &save_eh; /* MAC header for bridged/MAC packets */ - args.inp = NULL; /* used by ipfw uid/gid/jail rules */ - i = ipfw_chk(&args); - m = args.m; - if (m != NULL) { - /* - * Restore Ethernet header, as needed, in case the - * mbuf chain was replaced by ipfw. - */ - M_PREPEND(m, ETHER_HDR_LEN, M_DONTWAIT); - if (m == NULL) { - *m0 = NULL; - return (0); - } - if (eh != mtod(m, struct ether_header *)) - bcopy(&save_eh, mtod(m, struct ether_header *), - ETHER_HDR_LEN); - } - *m0 = m; - - ret = 0; - /* Check result of ipfw_chk() */ - switch (i) { - case IP_FW_PASS: - break; - - case IP_FW_DENY: - ret = EACCES; - break; /* i.e. drop */ - - case IP_FW_DUMMYNET: - ret = EACCES; - int dir; - - if (ip_dn_io_ptr == NULL) - break; /* i.e. drop */ - - *m0 = NULL; - dir = PROTO_LAYER2 | (dst ? DIR_OUT : DIR_IN); - ip_dn_io_ptr(&m, dir, &args); - return 0; - - default: - KASSERT(0, ("%s: unknown retval", __func__)); - } - - if (ret != 0) { - if (*m0) - FREE_PKT(*m0); - *m0 = NULL; - } - - return ret; -} - -/* do the divert, return 1 on error 0 on success */ -static int -ipfw_divert(struct mbuf **m0, int incoming, struct ipfw_rule_ref *rule, - int tee) -{ - /* - * ipfw_chk() has already tagged the packet with the divert tag. - * If tee is set, copy packet and return original. - * If not tee, consume packet and send it to divert socket. - */ - struct mbuf *clone; - struct ip *ip = mtod(*m0, struct ip *); - struct m_tag *tag; - - /* Cloning needed for tee? */ - if (tee == 0) { - clone = *m0; /* use the original mbuf */ - *m0 = NULL; - } else { - clone = m_dup(*m0, M_DONTWAIT); - /* If we cannot duplicate the mbuf, we sacrifice the divert - * chain and continue with the tee-ed packet. - */ - if (clone == NULL) - return 1; - } - - /* - * Divert listeners can normally handle non-fragmented packets, - * but we can only reass in the non-tee case. - * This means that listeners on a tee rule may get fragments, - * and have to live with that. - * Note that we now have the 'reass' ipfw option so if we care - * we can do it before a 'tee'. - */ - if (!tee) switch (ip->ip_v) { - case IPVERSION: - if (ntohs(ip->ip_off) & (IP_MF | IP_OFFMASK)) { - int hlen; - struct mbuf *reass; - - SET_HOST_IPLEN(ip); /* ip_reass wants host order */ - reass = ip_reass(clone); /* Reassemble packet. */ - if (reass == NULL) - return 0; /* not an error */ - /* if reass = NULL then it was consumed by ip_reass */ - /* - * IP header checksum fixup after reassembly and leave header - * in network byte order. - */ - ip = mtod(reass, struct ip *); - hlen = ip->ip_hl << 2; - SET_NET_IPLEN(ip); - ip->ip_sum = 0; - if (hlen == sizeof(struct ip)) - ip->ip_sum = in_cksum_hdr(ip); - else - ip->ip_sum = in_cksum(reass, hlen); - clone = reass; - } - break; -#ifdef INET6 - case IPV6_VERSION >> 4: - { - struct ip6_hdr *const ip6 = mtod(clone, struct ip6_hdr *); - - if (ip6->ip6_nxt == IPPROTO_FRAGMENT) { - int nxt, off; - - off = sizeof(struct ip6_hdr); - nxt = frag6_input(&clone, &off, 0); - if (nxt == IPPROTO_DONE) - return (0); - } - break; - } -#endif - } - - /* attach a tag to the packet with the reinject info */ - tag = m_tag_alloc(MTAG_IPFW_RULE, 0, - sizeof(struct ipfw_rule_ref), M_NOWAIT); - if (tag == NULL) { - FREE_PKT(clone); - return 1; - } - *((struct ipfw_rule_ref *)(tag+1)) = *rule; - m_tag_prepend(clone, tag); - - /* Do the dirty job... */ - ip_divert_ptr(clone, incoming); - return 0; -} - -/* - * attach or detach hooks for a given protocol family - */ -static int -ipfw_hook(int onoff, int pf) -{ - struct pfil_head *pfh; - void *hook_func; - - pfh = pfil_head_get(PFIL_TYPE_AF, pf); - if (pfh == NULL) - return ENOENT; - - hook_func = (pf == AF_LINK) ? ipfw_check_frame : ipfw_check_packet; - - (void) (onoff ? pfil_add_hook : pfil_remove_hook) - (hook_func, NULL, PFIL_IN | PFIL_OUT | PFIL_WAITOK, pfh); - - return 0; -} - -int -ipfw_attach_hooks(int arg) -{ - int error = 0; - - if (arg == 0) /* detach */ - ipfw_hook(0, AF_INET); - else if (V_fw_enable && ipfw_hook(1, AF_INET) != 0) { - error = ENOENT; /* see ip_fw_pfil.c::ipfw_hook() */ - printf("ipfw_hook() error\n"); - } -#ifdef INET6 - if (arg == 0) /* detach */ - ipfw_hook(0, AF_INET6); - else if (V_fw6_enable && ipfw_hook(1, AF_INET6) != 0) { - error = ENOENT; - printf("ipfw6_hook() error\n"); - } -#endif - if (arg == 0) /* detach */ - ipfw_hook(0, AF_LINK); - else if (V_fwlink_enable && ipfw_hook(1, AF_LINK) != 0) { - error = ENOENT; - printf("ipfw_link_hook() error\n"); - } - return error; -} - -int -ipfw_chg_hook(SYSCTL_HANDLER_ARGS) -{ - int *enable; - int newval; - int error; - int af; - - if (arg1 == &VNET_NAME(fw_enable)) { - enable = &V_fw_enable; - af = AF_INET; - } -#ifdef INET6 - else if (arg1 == &VNET_NAME(fw6_enable)) { - enable = &V_fw6_enable; - af = AF_INET6; - } -#endif - else if (arg1 == &VNET_NAME(fwlink_enable)) { - enable = &V_fwlink_enable; - af = AF_LINK; - } - else - return (EINVAL); - - newval = *enable; - - /* Handle sysctl change */ - error = sysctl_handle_int(oidp, &newval, 0, req); - - if (error) - return (error); - - /* Formalize new value */ - newval = (newval) ? 1 : 0; - - if (*enable == newval) - return (0); - - error = ipfw_hook(newval, af); - if (error) - return (error); - *enable = newval; - - return (0); -} -/* end of file */ |