freebsd-dev/sys/netpfil/pf/pf.h
Kristof Provost effaab8861 netpfil: Introduce PFIL_FWD flag
Forwarded packets passed through PFIL_OUT, which made it difficult for
firewalls to figure out if they were forwarding or producing packets. This in
turn is an issue for pf for IPv6 fragment handling: it needs to call
ip6_output() or ip6_forward() to handle the fragments. Figuring out which was
difficult (and until now, incorrect).
Having pfil distinguish the two removes an ugly piece of code from pf.

Introduce a new variant of the netpfil callbacks with a flags variable, which
has PFIL_FWD set for forwarded packets. This allows pf to reliably work out if
a packet is forwarded.

Reviewed by:	ae, kevans
Differential Revision:	https://reviews.freebsd.org/D13715
2018-03-23 16:56:44 +00:00

206 lines
7.2 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2001 Daniel Hartmeier
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - 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 COPYRIGHT HOLDERS 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
* COPYRIGHT HOLDERS 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.
*
* $OpenBSD: pfvar.h,v 1.282 2009/01/29 15:12:28 pyr Exp $
* $FreeBSD$
*/
#ifndef _NET_PF_H_
#define _NET_PF_H_
#define PF_TCPS_PROXY_SRC ((TCP_NSTATES)+0)
#define PF_TCPS_PROXY_DST ((TCP_NSTATES)+1)
#define PF_MD5_DIGEST_LENGTH 16
#ifdef MD5_DIGEST_LENGTH
#if PF_MD5_DIGEST_LENGTH != MD5_DIGEST_LENGTH
#error
#endif
#endif
enum { PF_INOUT, PF_IN, PF_OUT };
enum { PF_PASS, PF_DROP, PF_SCRUB, PF_NOSCRUB, PF_NAT, PF_NONAT,
PF_BINAT, PF_NOBINAT, PF_RDR, PF_NORDR, PF_SYNPROXY_DROP, PF_DEFER };
enum { PF_RULESET_SCRUB, PF_RULESET_FILTER, PF_RULESET_NAT,
PF_RULESET_BINAT, PF_RULESET_RDR, PF_RULESET_MAX };
enum { PF_OP_NONE, PF_OP_IRG, PF_OP_EQ, PF_OP_NE, PF_OP_LT,
PF_OP_LE, PF_OP_GT, PF_OP_GE, PF_OP_XRG, PF_OP_RRG };
enum { PF_DEBUG_NONE, PF_DEBUG_URGENT, PF_DEBUG_MISC, PF_DEBUG_NOISY };
enum { PF_CHANGE_NONE, PF_CHANGE_ADD_HEAD, PF_CHANGE_ADD_TAIL,
PF_CHANGE_ADD_BEFORE, PF_CHANGE_ADD_AFTER,
PF_CHANGE_REMOVE, PF_CHANGE_GET_TICKET };
enum { PF_GET_NONE, PF_GET_CLR_CNTR };
enum { PF_SK_WIRE, PF_SK_STACK, PF_SK_BOTH };
/*
* Note about PFTM_*: real indices into pf_rule.timeout[] come before
* PFTM_MAX, special cases afterwards. See pf_state_expires().
*/
enum { PFTM_TCP_FIRST_PACKET, PFTM_TCP_OPENING, PFTM_TCP_ESTABLISHED,
PFTM_TCP_CLOSING, PFTM_TCP_FIN_WAIT, PFTM_TCP_CLOSED,
PFTM_UDP_FIRST_PACKET, PFTM_UDP_SINGLE, PFTM_UDP_MULTIPLE,
PFTM_ICMP_FIRST_PACKET, PFTM_ICMP_ERROR_REPLY,
PFTM_OTHER_FIRST_PACKET, PFTM_OTHER_SINGLE,
PFTM_OTHER_MULTIPLE, PFTM_FRAG, PFTM_INTERVAL,
PFTM_ADAPTIVE_START, PFTM_ADAPTIVE_END, PFTM_SRC_NODE,
PFTM_TS_DIFF, PFTM_MAX, PFTM_PURGE, PFTM_UNLINKED };
/* PFTM default values */
#define PFTM_TCP_FIRST_PACKET_VAL 120 /* First TCP packet */
#define PFTM_TCP_OPENING_VAL 30 /* No response yet */
#define PFTM_TCP_ESTABLISHED_VAL 24*60*60/* Established */
#define PFTM_TCP_CLOSING_VAL 15 * 60 /* Half closed */
#define PFTM_TCP_FIN_WAIT_VAL 45 /* Got both FINs */
#define PFTM_TCP_CLOSED_VAL 90 /* Got a RST */
#define PFTM_UDP_FIRST_PACKET_VAL 60 /* First UDP packet */
#define PFTM_UDP_SINGLE_VAL 30 /* Unidirectional */
#define PFTM_UDP_MULTIPLE_VAL 60 /* Bidirectional */
#define PFTM_ICMP_FIRST_PACKET_VAL 20 /* First ICMP packet */
#define PFTM_ICMP_ERROR_REPLY_VAL 10 /* Got error response */
#define PFTM_OTHER_FIRST_PACKET_VAL 60 /* First packet */
#define PFTM_OTHER_SINGLE_VAL 30 /* Unidirectional */
#define PFTM_OTHER_MULTIPLE_VAL 60 /* Bidirectional */
#define PFTM_FRAG_VAL 30 /* Fragment expire */
#define PFTM_INTERVAL_VAL 10 /* Expire interval */
#define PFTM_SRC_NODE_VAL 0 /* Source tracking */
#define PFTM_TS_DIFF_VAL 30 /* Allowed TS diff */
enum { PF_NOPFROUTE, PF_FASTROUTE, PF_ROUTETO, PF_DUPTO, PF_REPLYTO };
enum { PF_LIMIT_STATES, PF_LIMIT_SRC_NODES, PF_LIMIT_FRAGS,
PF_LIMIT_TABLE_ENTRIES, PF_LIMIT_MAX };
#define PF_POOL_IDMASK 0x0f
enum { PF_POOL_NONE, PF_POOL_BITMASK, PF_POOL_RANDOM,
PF_POOL_SRCHASH, PF_POOL_ROUNDROBIN };
enum { PF_ADDR_ADDRMASK, PF_ADDR_NOROUTE, PF_ADDR_DYNIFTL,
PF_ADDR_TABLE, PF_ADDR_URPFFAILED,
PF_ADDR_RANGE };
#define PF_POOL_TYPEMASK 0x0f
#define PF_POOL_STICKYADDR 0x20
#define PF_WSCALE_FLAG 0x80
#define PF_WSCALE_MASK 0x0f
#define PF_LOG 0x01
#define PF_LOG_ALL 0x02
#define PF_LOG_SOCKET_LOOKUP 0x04
/* Reasons code for passing/dropping a packet */
#define PFRES_MATCH 0 /* Explicit match of a rule */
#define PFRES_BADOFF 1 /* Bad offset for pull_hdr */
#define PFRES_FRAG 2 /* Dropping following fragment */
#define PFRES_SHORT 3 /* Dropping short packet */
#define PFRES_NORM 4 /* Dropping by normalizer */
#define PFRES_MEMORY 5 /* Dropped due to lacking mem */
#define PFRES_TS 6 /* Bad TCP Timestamp (RFC1323) */
#define PFRES_CONGEST 7 /* Congestion (of ipintrq) */
#define PFRES_IPOPTIONS 8 /* IP option */
#define PFRES_PROTCKSUM 9 /* Protocol checksum invalid */
#define PFRES_BADSTATE 10 /* State mismatch */
#define PFRES_STATEINS 11 /* State insertion failure */
#define PFRES_MAXSTATES 12 /* State limit */
#define PFRES_SRCLIMIT 13 /* Source node/conn limit */
#define PFRES_SYNPROXY 14 /* SYN proxy */
#define PFRES_MAPFAILED 15 /* pf_map_addr() failed */
#define PFRES_MAX 16 /* total+1 */
#define PFRES_NAMES { \
"match", \
"bad-offset", \
"fragment", \
"short", \
"normalize", \
"memory", \
"bad-timestamp", \
"congestion", \
"ip-option", \
"proto-cksum", \
"state-mismatch", \
"state-insert", \
"state-limit", \
"src-limit", \
"synproxy", \
"map-failed", \
NULL \
}
/* Counters for other things we want to keep track of */
#define LCNT_STATES 0 /* states */
#define LCNT_SRCSTATES 1 /* max-src-states */
#define LCNT_SRCNODES 2 /* max-src-nodes */
#define LCNT_SRCCONN 3 /* max-src-conn */
#define LCNT_SRCCONNRATE 4 /* max-src-conn-rate */
#define LCNT_OVERLOAD_TABLE 5 /* entry added to overload table */
#define LCNT_OVERLOAD_FLUSH 6 /* state entries flushed */
#define LCNT_MAX 7 /* total+1 */
#define LCNT_NAMES { \
"max states per rule", \
"max-src-states", \
"max-src-nodes", \
"max-src-conn", \
"max-src-conn-rate", \
"overload table insertion", \
"overload flush states", \
NULL \
}
/* state operation counters */
#define FCNT_STATE_SEARCH 0
#define FCNT_STATE_INSERT 1
#define FCNT_STATE_REMOVALS 2
#define FCNT_MAX 3
/* src_node operation counters */
#define SCNT_SRC_NODE_SEARCH 0
#define SCNT_SRC_NODE_INSERT 1
#define SCNT_SRC_NODE_REMOVALS 2
#define SCNT_MAX 3
#define PF_TABLE_NAME_SIZE 32
#define PF_QNAME_SIZE 64
struct pf_status {
uint64_t counters[PFRES_MAX];
uint64_t lcounters[LCNT_MAX];
uint64_t fcounters[FCNT_MAX];
uint64_t scounters[SCNT_MAX];
uint64_t pcounters[2][2][3];
uint64_t bcounters[2][2];
uint32_t running;
uint32_t states;
uint32_t src_nodes;
uint32_t since;
uint32_t debug;
uint32_t hostid;
char ifname[IFNAMSIZ];
uint8_t pf_chksum[PF_MD5_DIGEST_LENGTH];
};
#endif /* _NET_PF_H_ */