summaryrefslogtreecommitdiffstats
path: root/sys
diff options
context:
space:
mode:
Diffstat (limited to 'sys')
-rw-r--r--sys/conf/files2
-rw-r--r--sys/netinet/ip_dummynet.c56
-rw-r--r--sys/netinet/ip_fw.h535
-rw-r--r--sys/netinet/ip_fw2.c2519
-rw-r--r--sys/netinet/libalias/alias_db.c118
5 files changed, 2953 insertions, 277 deletions
diff --git a/sys/conf/files b/sys/conf/files
index 413da1d..1cff41f 100644
--- a/sys/conf/files
+++ b/sys/conf/files
@@ -1164,7 +1164,7 @@ netinet/ip_ecn.c optional inet6
netinet/ip_encap.c optional inet
netinet/ip_encap.c optional inet6
netinet/ip_flow.c optional inet
-netinet/ip_fw.c optional ipfirewall
+netinet/ip_fw2.c optional ipfirewall
netinet/ip_icmp.c optional inet
netinet/ip_input.c optional inet
netinet/ip_mroute.c optional inet
diff --git a/sys/netinet/ip_dummynet.c b/sys/netinet/ip_dummynet.c
index 6006b65..7f8b241 100644
--- a/sys/netinet/ip_dummynet.c
+++ b/sys/netinet/ip_dummynet.c
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 1998-2001 Luigi Rizzo, Universita` di Pisa
+ * Copyright (c) 1998-2002 Luigi Rizzo, Universita` di Pisa
* Portions Copyright (c) 2000 Akamba Corp.
* All rights reserved
*
@@ -61,7 +61,6 @@
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
-#include <sys/queue.h> /* XXX */
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/proc.h>
@@ -166,12 +165,6 @@ static void dn_rule_delete(void *);
int if_tx_rdy(struct ifnet *ifp);
-/*
- * ip_fw_chain_head is used when deleting a pipe, because ipfw rules can
- * hold references to the pipe.
- */
-extern LIST_HEAD (ip_fw_head, ip_fw) ip_fw_chain_head;
-
static void
rt_unref(struct rtentry *rt)
{
@@ -1023,9 +1016,13 @@ static __inline
struct dn_flow_set *
locate_flowset(int pipe_nr, struct ip_fw *rule)
{
- struct dn_flow_set *fs = NULL ;
+ ipfw_insn_pipe *cmd = (ipfw_insn_pipe *)(rule->cmd + rule->act_ofs);
+ struct dn_flow_set *fs = (struct dn_flow_set *)(cmd->pipe_ptr);
- if ( (rule->fw_flg & IP_FW_F_COMMAND) == IP_FW_F_QUEUE )
+ if (fs != NULL)
+ return fs;
+
+ if ( cmd->o.opcode == O_QUEUE )
for (fs=all_flow_sets; fs && fs->fs_nr != pipe_nr; fs=fs->next)
;
else {
@@ -1035,8 +1032,7 @@ locate_flowset(int pipe_nr, struct ip_fw *rule)
if (p1 != NULL)
fs = &(p1->fs) ;
}
- if (fs != NULL)
- rule->pipe_ptr = fs ; /* record for the future */
+ (struct dn_flow_set *)(cmd->pipe_ptr) = fs; /* record for the future */
return fs ;
}
@@ -1065,16 +1061,18 @@ dummynet_io(struct mbuf *m, int pipe_nr, int dir, struct ip_fw_args *fwa)
u_int64_t len = m->m_pkthdr.len ;
struct dn_flow_queue *q = NULL ;
int s ;
+ int action = fwa->rule->cmd[fwa->rule->act_ofs].opcode;
s = splimp();
pipe_nr &= 0xffff ;
- if ( (fs = fwa->rule->pipe_ptr) == NULL ) {
- fs = locate_flowset(pipe_nr, fwa->rule);
- if (fs == NULL)
- goto dropit ; /* this queue/pipe does not exist! */
- }
+ /*
+ * this is a dummynet rule, so we expect a O_PIPE or O_QUEUE rule
+ */
+ fs = locate_flowset(pipe_nr, fwa->rule);
+ if (fs == NULL)
+ goto dropit ; /* this queue/pipe does not exist! */
pipe = fs->pipe ;
if (pipe == NULL) { /* must be a queue, try find a matching pipe */
for (pipe = all_pipes; pipe && pipe->pipe_nr != fs->parent_nr;
@@ -1152,7 +1150,7 @@ dummynet_io(struct mbuf *m, int pipe_nr, int dir, struct ip_fw_args *fwa)
* to schedule it. This involves different actions for fixed-rate or
* WF2Q queues.
*/
- if ( (fwa->rule->fw_flg & IP_FW_F_COMMAND) == IP_FW_F_PIPE ) {
+ if ( action == O_PIPE ) {
/*
* Fixed-rate queue: just insert into the ready_heap.
*/
@@ -1302,15 +1300,13 @@ static void
dummynet_flush()
{
struct dn_pipe *curr_p, *p ;
- struct ip_fw *rule ;
struct dn_flow_set *fs, *curr_fs;
int s ;
s = splimp() ;
/* remove all references to pipes ...*/
- LIST_FOREACH(rule, &ip_fw_chain_head, next)
- rule->pipe_ptr = NULL ;
+ flush_pipe_ptrs(NULL);
/* prevent future matches... */
p = all_pipes ;
all_pipes = NULL ;
@@ -1375,8 +1371,8 @@ dn_rule_delete(void *r)
fs = &(p->fs) ;
dn_rule_delete_fs(fs, r);
for (pkt = p->head ; pkt ; pkt = DN_NEXT(pkt) )
- if (pkt->rule == r)
- pkt->rule = ip_fw_default_rule ;
+ if (pkt->hdr.mh_data == r)
+ pkt->hdr.mh_data = (void *)ip_fw_default_rule ;
}
}
@@ -1663,7 +1659,6 @@ static int
delete_pipe(struct dn_pipe *p)
{
int s ;
- struct ip_fw *rule ;
if (p->pipe_nr == 0 && p->fs.fs_nr == 0)
return EINVAL ;
@@ -1687,9 +1682,7 @@ delete_pipe(struct dn_pipe *p)
else
a->next = b->next ;
/* remove references to this pipe from the ip_fw rules. */
- LIST_FOREACH(rule, &ip_fw_chain_head, next)
- if (rule->pipe_ptr == &(b->fs))
- rule->pipe_ptr = NULL ;
+ flush_pipe_ptrs(&(b->fs));
/* remove all references to this pipe from flow_sets */
for (fs = all_flow_sets; fs; fs= fs->next )
@@ -1721,9 +1714,7 @@ delete_pipe(struct dn_pipe *p)
else
a->next = b->next ;
/* remove references to this flow_set from the ip_fw rules. */
- LIST_FOREACH(rule, &ip_fw_chain_head, next)
- if (rule->pipe_ptr == b)
- rule->pipe_ptr = NULL ;
+ flush_pipe_ptrs(b);
if (b->pipe != NULL) {
/* Update total weight on parent pipe and cleanup parent heaps */
@@ -1847,9 +1838,14 @@ ip_dn_ctl(struct sockopt *sopt)
/* Disallow sets in really-really secure mode. */
if (sopt->sopt_dir == SOPT_SET) {
+#if __FreeBSD_version >= 500034
error = securelevel_ge(sopt->sopt_td->td_ucred, 3);
if (error)
return (error);
+#else
+ if (securelevel >= 3)
+ return (EPERM);
+#endif
}
switch (sopt->sopt_name) {
diff --git a/sys/netinet/ip_fw.h b/sys/netinet/ip_fw.h
index dcb3bcf..508cc76 100644
--- a/sys/netinet/ip_fw.h
+++ b/sys/netinet/ip_fw.h
@@ -1,183 +1,305 @@
/*
- * Copyright (c) 1993 Daniel Boulet
- * Copyright (c) 1994 Ugen J.S.Antsilevich
+ * Copyright (c) 2002 Luigi Rizzo, Universita` di Pisa
*
- * Redistribution and use in source forms, with and without modification,
- * are permitted provided that this entire comment appears intact.
+ * 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.
*
- * Redistribution in binary form may occur without any restrictions.
- * Obviously, it would be nice if you gave credit where credit is due
- * but requiring it would be too onerous.
- *
- * This software is provided ``AS IS'' without any warranties of any kind.
+ * 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.
*
* $FreeBSD$
*/
-#ifndef _IP_FW_H
-#define _IP_FW_H
-
-#include <sys/queue.h>
+#ifndef _IPFW2_H
+#define _IPFW2_H
/*
- * This union structure identifies an interface, either explicitly
- * by name or implicitly by IP address. The flags IP_FW_F_IIFNAME
- * and IP_FW_F_OIFNAME say how to interpret this structure. An
- * interface unit number of -1 matches any unit number, while an
- * IP address of 0.0.0.0 indicates matches any interface.
+ * The kernel representation of ipfw rules is made of a list of
+ * 'instructions' (for all practical purposes equivalent to BPF
+ * instructions), which specify which fields of the packet
+ * (or its metatada) should be analysed.
+ *
+ * Each instruction is stored in a structure which begins with
+ * "ipfw_insn", and can contain extra fields depending on the
+ * instruction type (listed below).
*
- * The receive and transmit interfaces are only compared against the
- * the packet if the corresponding bit (IP_FW_F_IIFACE or IP_FW_F_OIFACE)
- * is set. Note some packets lack a receive or transmit interface
- * (in which case the missing "interface" never matches).
+ * "enum ipfw_opcodes" are the opcodes supported. We can have up
+ * to 256 different opcodes.
*/
-union ip_fw_if {
- struct in_addr fu_via_ip; /* Specified by IP address */
- struct { /* Specified by interface name */
-#define FW_IFNLEN 10 /* need room ! was IFNAMSIZ */
- char name[FW_IFNLEN];
- short unit; /* -1 means match any unit */
- } fu_via_if;
+enum ipfw_opcodes { /* arguments (4 byte each) */
+ O_NOP,
+
+ O_IP_SRC, /* u32 = IP */
+ O_IP_SRC_MASK, /* ip = IP/mask */
+ O_IP_SRC_ME, /* none */
+ O_IP_SRC_SET, /* u32=base, arg1=len, bitmap */
+
+ O_IP_DST, /* u32 = IP */
+ O_IP_DST_MASK, /* ip = IP/mask */
+ O_IP_DST_ME, /* none */
+ O_IP_DST_SET, /* u32=base, arg1=len, bitmap */
+
+ O_IP_SRCPORT, /* (n)port list:mask 4 byte ea */
+ O_IP_DSTPORT, /* (n)port list:mask 4 byte ea */
+ O_PROTO, /* arg1=protocol */
+
+ O_MACADDR2, /* 2 mac addr:mask */
+ O_MAC_TYPE, /* same as srcport */
+
+ O_LAYER2, /* none */
+ O_IN, /* none */
+ O_FRAG, /* none */
+
+ O_RECV, /* none */
+ O_XMIT, /* none */
+ O_VIA, /* none */
+
+ O_IPOPT, /* arg1 = 2*u8 bitmap */
+ O_IPLEN, /* arg1 = len */
+ O_IPID, /* arg1 = id */
+
+ O_IPPRE, /* arg1 = id */
+ O_IPTOS, /* arg1 = id */
+ O_IPTTL, /* arg1 = TTL */
+
+ O_IPVER, /* arg1 = version */
+ O_UID, /* u32 = id */
+ O_GID, /* u32 = id */
+ O_ESTAB, /* none (tcp established) */
+ O_TCPFLAGS, /* arg1 = 2*u8 bitmap */
+ O_TCPWIN, /* arg1 = desired win */
+ O_TCPSEQ, /* u32 = desired seq. */
+ O_TCPACK, /* u32 = desired seq. */
+ O_ICMPTYPE, /* u32 = icmp bitmap */
+ O_TCPOPTS, /* arg1 = 2*u8 bitmap */
+ O_IPOPTS, /* arg1 = 2*u8 bitmap */
+
+ O_PROBE_STATE, /* none */
+ O_KEEP_STATE, /* none */
+ O_LIMIT, /* ipfw_insn_limit */
+ O_LIMIT_PARENT, /* dyn_type, not an opcode. */
+ /*
+ * these are really 'actions', and must be last in the list.
+ */
+
+ O_LOG, /* ipfw_insn_log */
+ O_PROB, /* u32 = match probability */
+
+ O_CHECK_STATE, /* none */
+ O_ACCEPT, /* none */
+ O_DENY, /* none */
+ O_REJECT, /* arg1=icmp arg (same as deny) */
+ O_COUNT, /* none */
+ O_SKIPTO, /* arg1=next rule number */
+ O_PIPE, /* arg1=pipe number */
+ O_QUEUE, /* arg1=queue number */
+ O_DIVERT, /* arg1=port number */
+ O_TEE, /* arg1=port number */
+ O_FORWARD_IP, /* fwd sockaddr */
+ O_FORWARD_MAC, /* fwd mac */
+ O_LAST_OPCODE /* not an opcode! */
};
/*
- * Format of an IP firewall descriptor
+ * Template for instructions.
+ *
+ * ipfw_insn is used for all instructions which require no operands,
+ * a single 16-bit value (arg1), or a couple of 8-bit values.
+ *
+ * For other instructions which require different/larger arguments
+ * we have derived structures, ipfw_insn_*.
+ *
+ * The size of the instruction (in 32-bit words) is in the low
+ * 6 bits of "len". The 2 remaining bits are used to implement
+ * NOT and OR on individual instructions. Given a type, you can
+ * compute the length to be put in "len" using F_INSN_SIZE(t)
+ *
+ * F_NOT negates the match result of the instruction.
+ *
+ * F_OR is used to build or blocks. By default, instructions
+ * are evaluated as part of a logical AND. An "or" block
+ * { X or Y or Z } contains F_OR set in all but the last
+ * instruction of the block. A match will cause the code
+ * to skip past the last instruction of the block.
+ *
+ * NOTA BENE: in a couple of places we assume that
+ * sizeof(ipfw_insn) == sizeof(u_int32_t)
+ * this needs to be fixed.
*
- * fw_src, fw_dst, fw_smsk, fw_dmsk are always stored in network byte order.
- * fw_flg and fw_n*p are stored in host byte order (of course).
- * Port numbers are stored in HOST byte order.
*/
+typedef struct _ipfw_insn { /* template for instructions */
+ enum ipfw_opcodes opcode:8;
+ u_int8_t len; /* numer of 32-byte words */
+#define F_NOT 0x80
+#define F_OR 0x40
+#define F_LEN_MASK 0x3f
+#define F_LEN(cmd) ((cmd)->len & F_LEN_MASK)
+
+ u_int16_t arg1;
+} ipfw_insn;
/*
- * To match MAC headers:
- * 12 bytes at fw_mac_hdr contain the dst-src MAC address after masking.
- * 12 bytes at fw_mac_mask contain the mask to apply to dst-src
- * 2 bytes at fw_mac_type contain the mac type after mask (in net format)
- * 2 bytes at fw_mac_type_mask contain the mac type mask
- * If IP_FW_F_SRNG, the two contain the low-high of a range of types.
- * IP_FW_F_DRNG is used to indicare we want to match a vlan.
+ * The F_INSN_SIZE(type) computes the size, in 4-byte words, of
+ * a given type.
*/
-#define fw_mac_hdr fw_src
-#define fw_mac_mask fw_uar
-#define fw_mac_type fw_iplen
-#define fw_mac_mask_type fw_ipid
+#define F_INSN_SIZE(t) ((sizeof (t))/sizeof(u_int32_t))
-struct ip_fw {
- LIST_ENTRY(ip_fw) next; /* bidirectional list of rules */
- u_int fw_flg; /* Operational Flags word */
- u_int64_t fw_pcnt; /* Packet counters */
- u_int64_t fw_bcnt; /* Byte counters */
-
- struct in_addr fw_src; /* Source IP address */
- struct in_addr fw_dst; /* Destination IP address */
- struct in_addr fw_smsk; /* Mask for source IP address */
- struct in_addr fw_dmsk; /* Mask for destination address */
- u_short fw_number; /* Rule number */
- u_char fw_prot; /* IP protocol */
-#if 1
- u_char fw_nports; /* # of src/dst port in array */
-#define IP_FW_GETNSRCP(rule) ((rule)->fw_nports & 0x0f)
-#define IP_FW_SETNSRCP(rule, n) do { \
- (rule)->fw_nports &= ~0x0f; \
- (rule)->fw_nports |= (n); \
- } while (0)
-#define IP_FW_GETNDSTP(rule) ((rule)->fw_nports >> 4)
-#define IP_FW_SETNDSTP(rule, n) do { \
- (rule)->fw_nports &= ~0xf0; \
- (rule)->fw_nports |= (n) << 4;\
- } while (0)
-#define IP_FW_HAVEPORTS(rule) ((rule)->fw_nports != 0)
-#else
- u_char __pad[1];
- u_int _nsrcp;
- u_int _ndstp;
-#define IP_FW_GETNSRCP(rule) (rule)->_nsrcp
-#define IP_FW_SETNSRCP(rule,n) (rule)->_nsrcp = n
-#define IP_FW_GETNDSTP(rule) (rule)->_ndstp
-#define IP_FW_SETNDSTP(rule,n) (rule)->_ndstp = n
-#define IP_FW_HAVEPORTS(rule) ((rule)->_ndstp + (rule)->_nsrcp != 0)
-#endif
-#define IP_FW_MAX_PORTS 10 /* A reasonable maximum */
- union {
- u_short fw_pts[IP_FW_MAX_PORTS]; /* port numbers to match */
-#define IP_FW_ICMPTYPES_MAX 128
-#define IP_FW_ICMPTYPES_DIM (IP_FW_ICMPTYPES_MAX / (sizeof(unsigned) * 8))
- unsigned fw_icmptypes[IP_FW_ICMPTYPES_DIM]; /*ICMP types bitmap*/
- } fw_uar;
-
- u_int fw_ipflg; /* IP flags word */
- u_short fw_iplen; /* IP length */
- u_short fw_ipid; /* Identification */
- u_char fw_ipopt; /* IP options set */
- u_char fw_ipnopt; /* IP options unset */
- u_char fw_iptos; /* IP type of service set */
- u_char fw_ipntos; /* IP type of service unset */
- u_char fw_ipttl; /* IP time to live */
- u_int fw_ipver:4; /* IP version */
- u_char fw_tcpopt; /* TCP options set */
- u_char fw_tcpnopt; /* TCP options unset */
- u_char fw_tcpf; /* TCP flags set */
- u_char fw_tcpnf; /* TCP flags unset */
- u_short fw_tcpwin; /* TCP window size */
- u_int32_t fw_tcpseq; /* TCP sequence */
- u_int32_t fw_tcpack; /* TCP acknowledgement */
- long timestamp; /* timestamp (tv_sec) of last match */
- union ip_fw_if fw_in_if; /* Incoming interfaces */
- union ip_fw_if fw_out_if; /* Outgoing interfaces */
- union {
- u_short fu_divert_port; /* Divert/tee port (options IPDIVERT) */
- u_short fu_pipe_nr; /* queue number (option DUMMYNET) */
- u_short fu_skipto_rule; /* SKIPTO command rule number */
- u_short fu_reject_code; /* REJECT response code */
- struct sockaddr_in fu_fwd_ip;
- } fw_un;
- void *pipe_ptr; /* flow_set ptr for dummynet pipe */
- void *next_rule_ptr; /* next rule in case of match */
- uid_t fw_uid; /* uid to match */
- gid_t fw_gid; /* gid to match */
- int fw_logamount; /* amount to log */
- u_int64_t fw_loghighest; /* highest number packet to log */
-
- long dont_match_prob; /* 0x7fffffff means 1.0, always fail */
- u_char dyn_type; /* type for dynamic rule */
-
-#define DYN_KEEP_STATE 0 /* type for keep-state rules */
-#define DYN_LIMIT 1 /* type for limit connection rules */
-#define DYN_LIMIT_PARENT 2 /* parent entry for limit connection rules */
-
- /* following two fields are used to limit number of connections
- * basing on either src, srcport, dst, dstport.
- */
- u_char limit_mask; /* mask type for limit rule, can
- * have many.
- */
+/*
+ * This is used to store an array of 16-bit entries (ports etc.)
+ */
+typedef struct _ipfw_insn_u16 {
+ ipfw_insn o;
+ u_int16_t ports[2]; /* there may be more */
+} ipfw_insn_u16;
+
+/*
+ * This is used to store an array of 32-bit entries
+ * (uid, single IPv4 addresses etc.)
+ */
+typedef struct _ipfw_insn_u32 {
+ ipfw_insn o;
+ u_int32_t d[1]; /* one or more */
+} ipfw_insn_u32;
+
+/*
+ * This is used to store IP addr-mask pairs.
+ */
+typedef struct _ipfw_insn_ip {
+ ipfw_insn o;
+ struct in_addr addr;
+ struct in_addr mask;
+} ipfw_insn_ip;
+
+/*
+ * This is used to forward to a given address (ip)
+ */
+typedef struct _ipfw_insn_sa {
+ ipfw_insn o;
+ struct sockaddr_in sa;
+} ipfw_insn_sa;
+
+/*
+ * This is used for MAC addr-mask pairs.
+ */
+typedef struct _ipfw_insn_mac {
+ ipfw_insn o;
+ u_char addr[12]; /* dst[6] + src[6] */
+ u_char mask[12]; /* dst[6] + src[6] */
+} ipfw_insn_mac;
+
+/*
+ * This is used for interface match rules (recv xx, xmit xx)
+ */
+typedef struct _ipfw_insn_if {
+ ipfw_insn o;
+ union {
+ struct in_addr ip;
+ int unit;
+ } p;
+ char name[IFNAMSIZ];
+} ipfw_insn_if;
+
+/*
+ * This is used for pipe and queue actions, which need to store
+ * a single pointer (which can have different size on different
+ * architectures.
+ */
+typedef struct _ipfw_insn_pipe {
+ ipfw_insn o;
+ void *pipe_ptr;
+} ipfw_insn_pipe;
+
+/*
+ * This is used for limit rules.
+ */
+typedef struct _ipfw_insn_limit {
+ ipfw_insn o;
+ u_int8_t _pad;
+ u_int8_t limit_mask; /* combination of DYN_* below */
#define DYN_SRC_ADDR 0x1
#define DYN_SRC_PORT 0x2
#define DYN_DST_ADDR 0x4
#define DYN_DST_PORT 0x8
- u_short conn_limit; /* # of connections for limit rule */
-};
+ u_int16_t conn_limit;
+} ipfw_insn_limit;
-#define fw_divert_port fw_un.fu_divert_port
-#define fw_skipto_rule fw_un.fu_skipto_rule
-#define fw_reject_code fw_un.fu_reject_code
-#define fw_pipe_nr fw_un.fu_pipe_nr
-#define fw_fwd_ip fw_un.fu_fwd_ip
+/*
+ * This is used for log instructions
+ */
+typedef struct _ipfw_insn_log {
+ ipfw_insn o;
+ u_int32_t max_log; /* how many do we log -- 0 = all */
+ u_int32_t log_left; /* how many left to log */
+} ipfw_insn_log;
/*
+ * Here we have the structure representing an ipfw rule.
+ *
+ * It starts with a general area (with link fields and counters)
+ * followed by an array of one or more instructions, which the code
+ * accesses as an array of 32-bit values.
+ *
+ * Given a rule pointer r:
+ *
+ * r->cmd is the start of the first instruction.
+ * ACTION_PTR(r) is the start of the first action (things to do
+ * once a rule matched).
+ *
+ * When assembling instruction, remember the following:
*
- * rule_ptr -------------+
- * V
- * [ next.le_next ]---->[ next.le_next ]---- [ next.le_next ]--->
- * [ next.le_prev ]<----[ next.le_prev ]<----[ next.le_prev ]<---
- * [ <ip_fw> body ] [ <ip_fw> body ] [ <ip_fw> body ]
+ * + if a rule has a "keep-state" (or "limit") option, then the
+ * first instruction (at r->cmd) MUST BE an O_PROBE_STATE
+ * + if a rule has a "log" option, then the first action
+ * (at ACTION_PTR(r)) MUST be O_LOG
*
+ * NOTE: we use a simple linked list of rules because we never need
+ * to delete a rule without scanning the list. We do not use
+ * queue(3) macros for portability and readability.
*/
+struct ip_fw {
+ struct ip_fw *next; /* linked list of rules */
+ u_int16_t act_ofs; /* offset of action in 32-bit units */
+ u_int16_t cmd_len; /* # of 32-bit words in cmd */
+ u_int16_t rulenum; /* rule number */
+ u_int16_t _pad; /* padding */
+
+ /* These fields are present in all rules. */
+ u_int64_t pcnt; /* Packet counter */
+ u_int64_t bcnt; /* Byte counter */
+ u_int32_t timestamp; /* tv_sec of last match */
+
+ struct ip_fw *next_rule; /* ptr to next rule */
+
+ ipfw_insn cmd[1]; /* storage for commands */
+};
+
+#define ACTION_PTR(rule) \
+ (ipfw_insn *)( (u_int32_t *)((rule)->cmd) + ((rule)->act_ofs) )
+
+#define RULESIZE(rule) (sizeof(struct ip_fw) + \
+ ((struct ip_fw *)(rule))->cmd_len * 4 - 4)
+
/*
- * Flow mask/flow id for each queue.
+ * This structure is used as a flow mask and a flow id for various
+ * parts of the code.
*/
struct ipfw_flow_id {
u_int32_t dst_ip;
@@ -191,108 +313,25 @@ struct ipfw_flow_id {
/*
* dynamic ipfw rule
*/
-struct ipfw_dyn_rule {
- struct ipfw_dyn_rule *next;
- struct ipfw_flow_id id; /* (masked) flow id */
- struct ip_fw *rule; /* pointer to rule */
- struct ipfw_dyn_rule *parent; /* pointer to parent rule */
- u_int32_t expire; /* expire time */
- u_int64_t pcnt; /* packet match counters */
- u_int64_t bcnt; /* byte match counters */
- u_int32_t bucket; /* which bucket in hash table */
+typedef struct _ipfw_dyn_rule ipfw_dyn_rule;
+
+struct _ipfw_dyn_rule {
+ ipfw_dyn_rule *next; /* linked list of rules. */
+ struct ipfw_flow_id id; /* (masked) flow id */
+ struct ip_fw *rule; /* pointer to rule */
+ ipfw_dyn_rule *parent; /* pointer to parent rule */
+ u_int32_t expire; /* expire time */
+ u_int64_t pcnt; /* packet match counter */
+ u_int64_t bcnt; /* byte match counter */
+ u_int32_t bucket; /* which bucket in hash table */
u_int32_t state; /* state of this rule (typically a
* combination of TCP flags)
*/
- u_int16_t dyn_type; /* rule type */
- u_int16_t count; /* refcount */
+ u_int16_t dyn_type; /* rule type */
+ u_int16_t count; /* refcount */
};
/*
- * Values for "flags" field .
- */
-#define IP_FW_F_COMMAND 0x000000ff /* Mask for type of chain entry: */
-#define IP_FW_F_DENY 0x00000000 /* This is a deny rule */
-#define IP_FW_F_REJECT 0x00000001 /* Deny and send a response packet */
-#define IP_FW_F_ACCEPT 0x00000002 /* This is an accept rule */
-#define IP_FW_F_COUNT 0x00000003 /* This is a count rule */
-#define IP_FW_F_DIVERT 0x00000004 /* This is a divert rule */
-#define IP_FW_F_TEE 0x00000005 /* This is a tee rule */
-#define IP_FW_F_SKIPTO 0x00000006 /* This is a skipto rule */
-#define IP_FW_F_FWD 0x00000007 /* This is a "change forwarding
- * address" rule
- */
-#define IP_FW_F_PIPE 0x00000008 /* This is a dummynet rule */
-#define IP_FW_F_QUEUE 0x00000009 /* This is a dummynet queue */
-
-#define IP_FW_F_IN 0x00000100 /* Check inbound packets */
-#define IP_FW_F_OUT 0x00000200 /* Check outbound packets */
-#define IP_FW_F_IIFACE 0x00000400 /* Apply inbound interface test */
-#define IP_FW_F_OIFACE 0x00000800 /* Apply outbound interface test */
-#define IP_FW_F_PRN 0x00001000 /* Print if this rule matches */
-#define IP_FW_F_SRNG 0x00002000 /* The first two src ports are a min
- * and max range (stored in host byte
- * order).
- */
-#define IP_FW_F_DRNG 0x00004000 /* The first two dst ports are a min
- * and max range (stored in host byte
- * order).
- */
-#define IP_FW_F_FRAG 0x00008000 /* Fragment */
-#define IP_FW_F_IIFNAME 0x00010000 /* In interface by name/unit (not IP) */
-#define IP_FW_F_OIFNAME 0x00020000 /* Out interface by name/unit (not IP)*/
-#define IP_FW_F_INVSRC 0x00040000 /* Invert sense of src check */
-#define IP_FW_F_INVDST 0x00080000 /* Invert sense of dst check */
-#define IP_FW_F_ICMPBIT 0x00100000 /* ICMP type bitmap is valid */
-#define IP_FW_F_UID 0x00200000 /* filter by uid */
-#define IP_FW_F_GID 0x00400000 /* filter by gid */
-#define IP_FW_F_RND_MATCH 0x00800000 /* probabilistic rule match */
-#define IP_FW_F_SMSK 0x01000000 /* src-port + mask */
-#define IP_FW_F_DMSK 0x02000000 /* dst-port + mask */
-#define IP_FW_BRIDGED 0x04000000 /* only match bridged packets */
-#define IP_FW_F_KEEP_S 0x08000000 /* keep state */
-#define IP_FW_F_CHECK_S 0x10000000 /* check state */
-#define IP_FW_F_SME 0x20000000 /* source = me */
-#define IP_FW_F_DME 0x40000000 /* destination = me */
-#define IP_FW_F_MAC 0x80000000 /* match MAC header */
-
-#define IP_FW_F_MASK 0xFFFFFFFF /* All possible flag bits mask */
-
-/*
- * Flags for the 'fw_ipflg' field, for comparing values
- * of ip and its protocols.
- */
-#define IP_FW_IF_TCPOPT 0x00000001 /* tcp options */
-#define IP_FW_IF_TCPFLG 0x00000002 /* tcp flags */
-#define IP_FW_IF_TCPSEQ 0x00000004 /* tcp sequence number */
-#define IP_FW_IF_TCPACK 0x00000008 /* tcp acknowledgement number */
-#define IP_FW_IF_TCPWIN 0x00000010 /* tcp window size */
-#define IP_FW_IF_TCPEST 0x00000020 /* established TCP connection */
-#define IP_FW_IF_TCPMSK 0x0000003f /* mask of all tcp values */
-#define IP_FW_IF_IPOPT 0x00000100 /* ip options */
-#define IP_FW_IF_IPLEN 0x00000200 /* ip length */
-#define IP_FW_IF_IPID 0x00000400 /* ip identification */
-#define IP_FW_IF_IPTOS 0x00000800 /* ip type of service */
-#define IP_FW_IF_IPTTL 0x00001000 /* ip time to live */
-#define IP_FW_IF_IPVER 0x00002000 /* ip version */
-#define IP_FW_IF_IPPRE 0x00004000 /* ip precedence */
-#define IP_FW_IF_IPMSK 0x00007f00 /* mask of all ip values */
-#define IP_FW_IF_MSK 0x0000ffff /* All possible bits mask */
-
-/*
- * For backwards compatibility with rules specifying "via iface" but
- * not restricted to only "in" or "out" packets, we define this combination
- * of bits to represent this configuration.
- */
-
-#define IF_FW_F_VIAHACK (IP_FW_F_IN|IP_FW_F_OUT|IP_FW_F_IIFACE|IP_FW_F_OIFACE)
-
-/*
- * Definitions for REJECT response codes.
- * Values less than 256 correspond to ICMP unreachable codes.
- */
-#define IP_FW_REJECT_RST 0x0100 /* TCP packets: send RST */
-
-/*
* Definitions for IP option names.
*/
#define IP_FW_IPOPT_LSRR 0x01
@@ -309,6 +348,8 @@ struct ipfw_dyn_rule {
#define IP_FW_TCPOPT_TS 0x08
#define IP_FW_TCPOPT_CC 0x10
+#define ICMP_REJECT_RST 0x100 /* fake ICMP code (send a TCP RST) */
+
/*
* Main firewall chains definitions and global var's definitions.
*/
@@ -319,7 +360,7 @@ struct ipfw_dyn_rule {
#define IP_FW_PORT_DENY_FLAG 0x40000
/*
- * arguments for calling ip_fw_chk() and dummynet_io(). We put them
+ * arguments for calling ipfw_chk() and dummynet_io(). We put them
* all into a structure because this way it is easier and more
* efficient to pass variables around and extend the interface.
*/
@@ -342,11 +383,13 @@ struct ip_fw_args {
/*
* Function definitions.
*/
-void ip_fw_init(void);
/* Firewall hooks */
-struct ip;
struct sockopt;
+struct dn_flow_set;
+
+void flush_pipe_ptrs(struct dn_flow_set *match); /* used by dummynet */
+
typedef int ip_fw_chk_t (struct ip_fw_args *args);
typedef int ip_fw_ctl_t (struct sockopt *);
extern ip_fw_chk_t *ip_fw_chk_ptr;
@@ -356,4 +399,4 @@ extern int fw_enable;
#define IPFW_LOADED (ip_fw_chk_ptr != NULL)
#endif /* _KERNEL */
-#endif /* _IP_FW_H */
+#endif /* _IPFW2_H */
diff --git a/sys/netinet/ip_fw2.c b/sys/netinet/ip_fw2.c
new file mode 100644
index 0000000..194f628
--- /dev/null
+++ b/sys/netinet/ip_fw2.c
@@ -0,0 +1,2519 @@
+/*
+ * Copyright (c) 2002 Luigi Rizzo, Universita` di Pisa
+ *
+ * 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.
+ *
+ * $FreeBSD$
+ */
+
+#define DEB(x)
+#define DDB(x) x
+
+/*
+ * Implement IP packet firewall
+ */
+
+#if !defined(KLD_MODULE)
+#include "opt_ipfw.h"
+#include "opt_ipdn.h"
+#include "opt_ipdivert.h"
+#include "opt_inet.h"
+#ifndef INET
+#error IPFIREWALL requires INET.
+#endif /* INET */
+#endif
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/malloc.h>
+#include <sys/mbuf.h>
+#include <sys/kernel.h>
+#include <sys/proc.h>
+#include <sys/socket.h>
+#include <sys/socketvar.h>
+#include <sys/sysctl.h>
+#include <sys/syslog.h>
+#include <sys/ucred.h>
+#include <net/if.h>
+#include <net/route.h>
+#include <netinet/in.h>
+#include <netinet/in_systm.h>
+#include <netinet/in_var.h>
+#include <netinet/in_pcb.h>
+#include <netinet/ip.h>
+#include <netinet/ip_var.h>
+#include <netinet/ip_icmp.h>
+#include <netinet/ip_fw.h>
+#include <netinet/ip_dummynet.h>
+#include <netinet/tcp.h>
+#include <netinet/tcp_timer.h>
+#include <netinet/tcp_var.h>
+#include <netinet/tcpip.h>
+#include <netinet/udp.h>
+#include <netinet/udp_var.h>
+
+#include <netinet/if_ether.h> /* XXX for ETHERTYPE_IP */
+
+static int fw_verbose = 0;
+static int verbose_limit = 0;
+
+#define IPFW_DEFAULT_RULE 65535
+
+/*
+ * list of rules for layer 3
+ */
+static struct ip_fw *layer3_chain;
+
+MALLOC_DEFINE(M_IPFW, "IpFw/IpAcct", "IpFw/IpAcct chain's");
+
+static int fw_debug = 1;
+int fw_one_pass = 1;
+static int autoinc_step = 100; /* bounded to 1..1000 in add_rule() */
+
+#ifdef SYSCTL_NODE
+SYSCTL_NODE(_net_inet_ip, OID_AUTO, fw, CTLFLAG_RW, 0, "Firewall");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, enable, CTLFLAG_RW,
+ &fw_enable, 0, "Enable ipfw");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, autoinc_step, CTLFLAG_RW,
+ &autoinc_step, 0, "Rule number autincrement step");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO,one_pass,CTLFLAG_RW,
+ &fw_one_pass, 0,
+ "Only do a single pass through ipfw when using dummynet(4)");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, debug, CTLFLAG_RW,
+ &fw_debug, 0, "Enable printing of debug ip_fw statements");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, verbose, CTLFLAG_RW,
+ &fw_verbose, 0, "Log matches to ipfw rules");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, verbose_limit, CTLFLAG_RW,
+ &verbose_limit, 0, "Set upper limit of matches of ipfw rules logged");
+
+/*
+ * Description of dynamic rules.
+ *
+ * Dynamic rules are stored in lists accessed through a hash table
+ * (ipfw_dyn_v) whose size is curr_dyn_buckets. This value can
+ * be modified through the sysctl variable dyn_buckets which is
+ * updated when the table becomes empty.
+ *
+ * XXX currently there is only one list, ipfw_dyn.
+ *
+ * When a packet is received, its address fields are first masked
+ * with the mask defined for the rule, then hashed, then matched
+ * against the entries in the corresponding list.
+ * Dynamic rules can be used for different purposes:
+ * + stateful rules;
+ * + enforcing limits on the number of sessions;
+ * + in-kernel NAT (not implemented yet)
+ *
+ * The lifetime of dynamic rules is regulated by dyn_*_lifetime,
+ * measured in seconds and depending on the flags.
+ *
+ * The total number of dynamic rules is stored in dyn_count.
+ * The max number of dynamic rules is dyn_max. When we reach
+ * the maximum number of rules we do not create anymore. This is
+ * done to avoid consuming too much memory, but also too much
+ * time when searching on each packet (ideally, we should try instead
+ * to put a limit on the length of the list on each bucket...).
+ *
+ * Each dynamic rule holds a pointer to the parent ipfw rule so
+ * we know what action to perform. Dynamic rules are removed when
+ * the parent rule is deleted. XXX we should make them survive.
+ *
+ * There are some limitations with dynamic rules -- we do not
+ * obey the 'randomized match', and we do not do multiple
+ * passes through the firewall. XXX check the latter!!!
+ */
+static ipfw_dyn_rule **ipfw_dyn_v = NULL;
+static u_int32_t dyn_buckets = 256; /* must be power of 2 */
+static u_int32_t curr_dyn_buckets = 256; /* must be power of 2 */
+
+/*
+ * Timeouts for various events in handing dynamic rules.
+ */
+static u_int32_t dyn_ack_lifetime = 300;
+static u_int32_t dyn_syn_lifetime = 20;
+static u_int32_t dyn_fin_lifetime = 1;
+static u_int32_t dyn_rst_lifetime = 1;
+static u_int32_t dyn_udp_lifetime = 10;
+static u_int32_t dyn_short_lifetime = 5;
+
+/*
+ * After reaching 0, dynamic rules are considered still valid for
+ * an additional grace time, unless there is lack of resources.
+ * XXX not implemented yet.
+ */
+static u_int32_t dyn_grace_time = 10;
+
+static u_int32_t static_count = 0; /* # of static rules */
+static u_int32_t static_len = 0; /* size in bytes of static rules */
+static u_int32_t dyn_count = 0; /* # of dynamic rules */
+static u_int32_t dyn_max = 1000; /* max # of dynamic rules */
+
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_buckets, CTLFLAG_RW,
+ &dyn_buckets, 0, "Number of dyn. buckets");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, curr_dyn_buckets, CTLFLAG_RD,
+ &curr_dyn_buckets, 0, "Current Number of dyn. buckets");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_count, CTLFLAG_RD,
+ &dyn_count, 0, "Number of dyn. rules");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_max, CTLFLAG_RW,
+ &dyn_max, 0, "Max number of dyn. rules");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, static_count, CTLFLAG_RD,
+ &static_count, 0, "Number of static rules");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_ack_lifetime, CTLFLAG_RW,
+ &dyn_ack_lifetime, 0, "Lifetime of dyn. rules for acks");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_syn_lifetime, CTLFLAG_RW,
+ &dyn_syn_lifetime, 0, "Lifetime of dyn. rules for syn");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_fin_lifetime, CTLFLAG_RW,
+ &dyn_fin_lifetime, 0, "Lifetime of dyn. rules for fin");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_rst_lifetime, CTLFLAG_RW,
+ &dyn_rst_lifetime, 0, "Lifetime of dyn. rules for rst");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_udp_lifetime, CTLFLAG_RW,
+ &dyn_udp_lifetime, 0, "Lifetime of dyn. rules for UDP");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_short_lifetime, CTLFLAG_RW,
+ &dyn_short_lifetime, 0, "Lifetime of dyn. rules for other situations");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_grace_time, CTLFLAG_RD,
+ &dyn_grace_time, 0, "Grace time for dyn. rules");
+
+#endif /* SYSCTL_NODE */
+
+
+static ip_fw_chk_t ipfw_chk;
+
+ip_dn_ruledel_t *ip_dn_ruledel_ptr = NULL; /* hook into dummynet */
+
+/*
+ * This macro maps an ip pointer into a layer3 header pointer of type T
+ */
+#define L3HDR(T, ip) ((T *)((u_int32_t *)(ip) + (ip)->ip_hl))
+
+static int
+icmptype_match(struct ip *ip, ipfw_insn_u32 *cmd)
+{
+ int type = L3HDR(struct icmp,ip)->icmp_type;
+
+ return (type <= ICMP_MAXTYPE && (cmd->d[0] & (1<<type)) );
+}
+
+#define TT ( (1 << ICMP_ECHO) | (1 << ICMP_ROUTERSOLICIT) | \
+ (1 << ICMP_TSTAMP) | (1 << ICMP_IREQ) | (1 << ICMP_MASKREQ) )
+
+static int
+is_icmp_query(struct ip *ip)
+{
+ int type = L3HDR(struct icmp, ip)->icmp_type;
+ return (type <= ICMP_MAXTYPE && (TT & (1<<type)) );
+}
+#undef TT
+
+/*
+ * The following checks use two arrays of 8 or 16 bits to store the
+ * bits that we want set or clear, respectively. They are in the
+ * low and high half of cmd->arg1 or cmd->d[0].
+ *
+ * We scan options and store the bits we find set. We succeed if
+ *
+ * (want_set & ~bits) == 0 && (want_clear & ~bits) == want_clear
+ *
+ * The code is sometimes optimized not to store additional variables.
+ */
+
+static int
+flags_match(ipfw_insn *cmd, u_int8_t bits)
+{
+ u_char want_clear;
+ bits = ~bits;
+
+ if ( ((cmd->arg1 & 0xff) & bits) != 0)
+ return 0; /* some bits we want set were clear */
+ want_clear = (cmd->arg1 >> 8) & 0xff;
+ if ( (want_clear & bits) != want_clear)
+ return 0; /* some bits we want clear were set */
+ return 1;
+}
+
+static int
+ipopts_match(struct ip *ip, ipfw_insn *cmd)
+{
+ int optlen, bits = 0;
+ u_char *cp = (u_char *)(ip + 1);
+ int x = (ip->ip_hl << 2) - sizeof (struct ip);
+
+ for (; x > 0; x -= optlen, cp += optlen) {
+ int opt = cp[IPOPT_OPTVAL];
+
+ if (opt == IPOPT_EOL)
+ break;
+ if (opt == IPOPT_NOP)
+ optlen = 1;
+ else {
+ optlen = cp[IPOPT_OLEN];
+ if (optlen <= 0 || optlen > x)
+ return 0; /* invalid or truncated */
+ }
+ switch (opt) {
+
+ default:
+ break;
+
+ case IPOPT_LSRR:
+ bits |= IP_FW_IPOPT_LSRR;
+ break;
+
+ case IPOPT_SSRR:
+ bits |= IP_FW_IPOPT_SSRR;
+ break;
+
+ case IPOPT_RR:
+ bits |= IP_FW_IPOPT_RR;
+ break;
+
+ case IPOPT_TS:
+ bits |= IP_FW_IPOPT_TS;
+ break;
+ }
+ }
+ return (flags_match(cmd, bits));
+}
+
+static int
+tcpopts_match(struct ip *ip, ipfw_insn *cmd)
+{
+ int optlen, bits = 0;
+ struct tcphdr *tcp = L3HDR(struct tcphdr,ip);
+ u_char *cp = (u_char *)(tcp + 1);
+ int x = (tcp->th_off << 2) - sizeof(struct tcphdr);
+
+ for (; x > 0; x -= optlen, cp += optlen) {
+ int opt = cp[0];
+ if (opt == TCPOPT_EOL)
+ break;
+ if (opt == TCPOPT_NOP)
+ optlen = 1;
+ else {
+ optlen = cp[1];
+ if (optlen <= 0)
+ break;
+ }
+
+ switch (opt) {
+
+ default:
+ break;
+
+ case TCPOPT_MAXSEG:
+ bits |= IP_FW_TCPOPT_MSS;
+ break;
+
+ case TCPOPT_WINDOW:
+ bits |= IP_FW_TCPOPT_WINDOW;
+ break;
+
+ case TCPOPT_SACK_PERMITTED:
+ case TCPOPT_SACK:
+ bits |= IP_FW_TCPOPT_SACK;
+ break;
+
+ case TCPOPT_TIMESTAMP:
+ bits |= IP_FW_TCPOPT_TS;
+ break;
+
+ case TCPOPT_CC:
+ case TCPOPT_CCNEW:
+ case TCPOPT_CCECHO:
+ bits |= IP_FW_TCPOPT_CC;
+ break;
+ }
+ }
+ return (flags_match(cmd, bits));
+}
+
+/*
+ * XXX done
+ */
+static int
+iface_match(struct ifnet *ifp, ipfw_insn_if *cmd)
+{
+ if (ifp == NULL) /* no iface with this packet, match fails */
+ return 0;
+ /* Check by name or by IP address */
+ if (cmd->name[0] != '\0') { /* XXX by name */
+ /* Check unit number (-1 is wildcard) */
+ if (cmd->p.unit != -1 && cmd->p.unit != ifp->if_unit)
+ return(0);
+ /* Check name */
+ if (!strncmp(ifp->if_name, cmd->name, IFNAMSIZ))
+ return(1);
+ } else {
+ struct ifaddr *ia;
+
+ TAILQ_FOREACH(ia, &ifp->if_addrhead, ifa_link) {
+ if (ia->ifa_addr == NULL)
+ continue;
+ if (ia->ifa_addr->sa_family != AF_INET)
+ continue;
+ if (cmd->p.ip.s_addr == ((struct sockaddr_in *)
+ (ia->ifa_addr))->sin_addr.s_addr)
+ return(1); /* match */
+ }
+ }
+ return(0); /* no match, fail ... */
+}
+
+static u_int64_t norule_counter; /* counter for ipfw_log(NULL...) */
+
+#define SNPARGS(buf, len) buf + len, sizeof(buf) > len ? sizeof(buf) - len : 0
+/*
+ * We enter here when we have a rule with O_LOG.
+ */
+static void
+ipfw_log(struct ip_fw *f, u_int hlen, struct ether_header *eh,
+ struct mbuf *m, struct ifnet *oif)
+{
+ char *action;
+ char action2[32], proto[47], fragment[27];
+ int limit_reached = 0;
+
+ fragment[0] = '\0';
+ proto[0] = '\0';
+
+ if (f == NULL) { /* bogus pkt */
+ if (verbose_limit != 0 && norule_counter >= verbose_limit)
+ return;
+ norule_counter++;
+ if (norule_counter == verbose_limit)
+ limit_reached = verbose_limit;
+ action = "Refuse";
+ } else { /* O_LOG is the first action, find the real one */
+ ipfw_insn *cmd = ACTION_PTR(f);
+ ipfw_insn_log *l = (ipfw_insn_log *)cmd;
+
+ if (l->max_log != 0 && l->log_left == 0)
+ return;
+ l->log_left--;
+ if (l->log_left == 0)
+ limit_reached = l->max_log;
+ cmd += F_LEN(cmd); /* point to first action */
+ if (cmd->opcode == O_PROB)
+ cmd += F_LEN(cmd);
+
+ action = action2;
+ switch (cmd->opcode) {
+ case O_DENY:
+ action = "Deny";
+ break;
+ case O_REJECT:
+ action = (cmd->arg1==ICMP_REJECT_RST) ?
+ "Reset" : "Unreach";
+ break;
+ case O_ACCEPT:
+ action = "Accept";
+ break;
+ case O_COUNT:
+ action = "Count";
+ break;
+ case O_DIVERT:
+ snprintf(SNPARGS(action2, 0), "Divert %d",
+ cmd->arg1);
+ break;
+ case O_TEE:
+ snprintf(SNPARGS(action2, 0), "Tee %d",
+ cmd->arg1);
+ break;
+ case O_SKIPTO:
+ snprintf(SNPARGS(action2, 0), "SkipTo %d",
+ cmd->arg1);
+ break;
+ case O_PIPE:
+ snprintf(SNPARGS(action2, 0), "Pipe %d",
+ cmd->arg1);
+ break;
+ case O_QUEUE:
+ snprintf(SNPARGS(action2, 0), "Queue %d",
+ cmd->arg1);
+ break;
+ case O_FORWARD_IP: {
+ ipfw_insn_sa *sa = (ipfw_insn_sa *)cmd;
+
+ if (sa->sa.sin_port)
+ snprintf(SNPARGS(action2, 0),
+ "Forward to %s:%d",
+ inet_ntoa(sa->sa.sin_addr),
+ sa->sa.sin_port);
+ else
+ snprintf(SNPARGS(action2, 0), "Forward to %s",
+ inet_ntoa(sa->sa.sin_addr));
+ }
+ break;
+ default:
+ action = "UNKNOWN";
+ break;
+ }
+ }
+
+ if (hlen == 0) { /* non-ip */
+ snprintf(SNPARGS(proto, 0), "MAC");
+ } else {
+ struct ip *ip = mtod(m, struct ip *);
+ /* these three are all aliases to the same thing */
+ struct icmp *const icmp = L3HDR(struct icmp, ip);
+ struct tcphdr *const tcp = (struct tcphdr *)icmp;
+ struct udphdr *const udp = (struct udphdr *)icmp;
+
+ int ip_off, offset, ip_len;
+
+ int len;
+
+ if (eh != NULL) { /* layer 2 packets are as on the wire */
+ ip_off = ntohs(ip->ip_off);
+ ip_len = ntohs(ip->ip_len);
+ } else {
+ ip_off = ip->ip_off;
+ ip_len = ip->ip_len;
+ }
+ offset = ip_off & IP_OFFMASK;
+ switch (ip->ip_p) {
+ case IPPROTO_TCP:
+ len = snprintf(SNPARGS(proto, 0), "TCP %s",
+ inet_ntoa(ip->ip_src));
+ if (offset == 0)
+ len += snprintf(SNPARGS(proto, len), ":%d ",
+ ntohs(tcp->th_sport));
+ else
+ len += snprintf(SNPARGS(proto, len), " ");
+ len += snprintf(SNPARGS(proto, len), "%s",
+ inet_ntoa(ip->ip_dst));
+ if (offset == 0)
+ snprintf(SNPARGS(proto, len), ":%d",
+ ntohs(tcp->th_dport));
+ break;
+
+ case IPPROTO_UDP:
+ len = snprintf(SNPARGS(proto, 0), "UDP %s",
+ inet_ntoa(ip->ip_src));
+ if (offset == 0)
+ len += snprintf(SNPARGS(proto, len), ":%d ",
+ ntohs(udp->uh_sport));
+ else
+ len += snprintf(SNPARGS(proto, len), " ");
+ len += snprintf(SNPARGS(proto, len), "%s",
+ inet_ntoa(ip->ip_dst));
+ if (offset == 0)
+ snprintf(SNPARGS(proto, len), ":%d",
+ ntohs(udp->uh_dport));
+ break;
+
+ case IPPROTO_ICMP:
+ if (offset == 0)
+ len = snprintf(SNPARGS(proto, 0),
+ "ICMP:%u.%u ",
+ icmp->icmp_type, icmp->icmp_code);
+ else
+ len = snprintf(SNPARGS(proto, 0), "ICMP ");
+ len += snprintf(SNPARGS(proto, len), "%s",
+ inet_ntoa(ip->ip_src));
+ snprintf(SNPARGS(proto, len), " %s",
+ inet_ntoa(ip->ip_dst));
+ break;
+
+ default:
+ len = snprintf(SNPARGS(proto, 0), "P:%d %s", ip->ip_p,
+ inet_ntoa(ip->ip_src));
+ snprintf(SNPARGS(proto, len), " %s",
+ inet_ntoa(ip->ip_dst));
+ break;
+ }
+
+ if (ip_off & (IP_MF | IP_OFFMASK))
+ snprintf(SNPARGS(fragment, 0), " (frag %d:%d@%d%s)",
+ ntohs(ip->ip_id), ip_len - (ip->ip_hl << 2),
+ offset << 3,
+ (ip_off & IP_MF) ? "+" : "");
+ }
+ if (oif || m->m_pkthdr.rcvif)
+ log(LOG_SECURITY | LOG_INFO,
+ "ipfw: %d %s %s %s via %s%d%s\n",
+ f ? f->rulenum : -1,
+ action, proto, oif ? "out" : "in",
+ oif ? oif->if_name : m->m_pkthdr.rcvif->if_name,
+ oif ? oif->if_unit : m->m_pkthdr.rcvif->if_unit,
+ fragment);
+ else
+ log(LOG_SECURITY | LOG_INFO,
+ "ipfw: %d %s %s [no if info]%s\n",
+ f ? f->rulenum : -1,
+ action, proto, fragment);
+ if (limit_reached)
+ log(LOG_SECURITY | LOG_NOTICE,
+ "ipfw: limit %d reached on entry %d\n",
+ limit_reached, f ? f->rulenum : -1);
+}
+
+/*
+ * IMPORTANT: the hash function for dynamic rules must be commutative
+ * in * source and destination (ip,port), because rules are bidirectional
+ * and we want to find both in the same bucket.
+ */
+static __inline int
+hash_packet(struct ipfw_flow_id *id)
+{
+ u_int32_t i;
+
+ i = (id->dst_ip) ^ (id->src_ip) ^ (id->dst_port) ^ (id->src_port);
+ i &= (curr_dyn_buckets - 1);
+ return i;
+}
+
+/**
+ * unlink a dynamic rule from a chain. prev is a pointer to
+ * the previous one, q is a pointer to the rule to delete,
+ * head is a pointer to the head of the queue.
+ * Modifies q and potentially also head.
+ */
+#define UNLINK_DYN_RULE(prev, head, q) { \
+ ipfw_dyn_rule *old_q = q; \
+ \
+ /* remove a refcount to the parent */ \
+ if (q->dyn_type == O_LIMIT) \
+ q->parent->count--; \
+ DEB(printf("-- unlink entry 0x%08x %d -> 0x%08x %d, %d left\n", \
+ (q->id.src_ip), (q->id.src_port), \
+ (q->id.dst_ip), (q->id.dst_port), dyn_count-1 ); ) \
+ if (prev != NULL) \
+ prev->next = q = q->next; \
+ else \
+ head = q = q->next; \
+ dyn_count--; \
+ free(old_q, M_IPFW); }
+
+#define TIME_LEQ(a,b) ((int)((a)-(b)) <= 0)
+
+/**
+ * Remove dynamic rules pointing to "rule", or all of them if rule == NULL.
+ *
+ * If keep_me == NULL, rules are deleted even if not expired,
+ * otherwise only expired rules are removed.
+ *
+ * The value of the second parameter is also used to point to identify
+ * a rule we absolutely do not want to remove (e.g. because we are
+ * holding a reference to it -- this is the case with O_LIMIT_PARENT
+ * rules). The pointer is only used for comparison, so any non-null
+ * value will do.
+ */
+static void
+remove_dyn_rule(struct ip_fw *rule, ipfw_dyn_rule *keep_me)
+{
+ static u_int32_t last_remove = 0;
+
+#define FORCE (keep_me == NULL)
+
+ ipfw_dyn_rule *prev, *q;
+ int i, pass = 0, max_pass = 0;
+
+ if (ipfw_dyn_v == NULL || dyn_count == 0)
+ return;
+ /* do not expire more than once per second, it is useless */
+ if (!FORCE && last_remove == time_second)
+ return;
+ last_remove = time_second;
+
+ /*
+ * because O_LIMIT refer to parent rules, during the first pass only
+ * remove child and mark any pending LIMIT_PARENT, and remove
+ * them in a second pass.
+ */
+next_pass:
+ for (i = 0 ; i < curr_dyn_buckets ; i++) {
+ for (prev=NULL, q = ipfw_dyn_v[i] ; q ; ) {
+ /*
+ * Logic can become complex here, so we split tests.
+ */
+ if (q == keep_me)
+ goto next;
+ if (rule != NULL && rule != q->rule)
+ goto next; /* not the one we are looking for */
+ if (q->dyn_type == O_LIMIT_PARENT) {
+ /*
+ * handle parent in the second pass,
+ * record we need one.
+ */
+ max_pass = 1;
+ if (pass == 0)
+ goto next;
+ if (FORCE && q->count != 0 ) {
+ /* XXX should not happen! */
+ printf( "OUCH! cannot remove rule,"
+ " count %d\n", q->count);
+ }
+ } else {
+ if (!FORCE &&
+ !TIME_LEQ( q->expire, time_second ))
+ goto next;
+ }
+ UNLINK_DYN_RULE(prev, ipfw_dyn_v[i], q);
+ continue;
+next:
+ prev=q;
+ q=q->next;
+ }
+ }
+ if (pass++ < max_pass)
+ goto next_pass;
+}
+
+
+/**
+ * lookup a dynamic rule.
+ */
+static ipfw_dyn_rule *
+lookup_dyn_rule(struct ipfw_flow_id *pkt, int *match_direction)
+{
+ /*
+ * stateful ipfw extensions.
+ * Lookup into dynamic session queue
+ */
+#define MATCH_REVERSE 0
+#define MATCH_FORWARD 1
+#define MATCH_NONE 2
+#define MATCH_UNKNOWN 3
+ int i, dir = MATCH_NONE;
+ ipfw_dyn_rule *prev, *q=NULL;
+
+ if (ipfw_dyn_v == NULL)
+ goto done; /* not found */
+ i = hash_packet( pkt );
+ for (prev=NULL, q = ipfw_dyn_v[i] ; q != NULL ; ) {
+ if (q->dyn_type == O_LIMIT_PARENT)
+ goto next;
+ if (TIME_LEQ( q->expire, time_second)) { /* expire entry */
+ UNLINK_DYN_RULE(prev, ipfw_dyn_v[i], q);
+ continue;
+ }
+ if ( pkt->proto == q->id.proto) {
+ if (pkt->src_ip == q->id.src_ip &&
+ pkt->dst_ip == q->id.dst_ip &&
+ pkt->src_port == q->id.src_port &&
+ pkt->dst_port == q->id.dst_port ) {
+ dir = MATCH_FORWARD;
+ break;
+ }
+ if (pkt->src_ip == q->id.dst_ip &&
+ pkt->dst_ip == q->id.src_ip &&
+ pkt->src_port == q->id.dst_port &&
+ pkt->dst_port == q->id.src_port ) {
+ dir = MATCH_REVERSE;
+ break;
+ }
+ }
+next:
+ prev = q;
+ q = q->next;
+ }
+ if (q == NULL)
+ goto done; /* q = NULL, not found */
+
+ if ( prev != NULL) { /* found and not in front */
+ prev->next = q->next;
+ q->next = ipfw_dyn_v[i];
+ ipfw_dyn_v[i] = q;
+ }
+ if (pkt->proto == IPPROTO_TCP) { /* update state according to flags */
+ u_char flags = pkt->flags & (TH_FIN|TH_SYN|TH_RST);
+
+#define BOTH_SYN (TH_SYN | (TH_SYN << 8))
+#define BOTH_FIN (TH_FIN | (TH_FIN << 8))
+ q->state |= (dir == MATCH_FORWARD ) ? flags : (flags << 8);
+ switch (q->state) {
+ case TH_SYN: /* opening */
+ q->expire = time_second + dyn_syn_lifetime;
+ break;
+ case BOTH_SYN: /* move to established */
+ q->expire = time_second + dyn_ack_lifetime;
+ break;
+ case BOTH_SYN | TH_FIN : /* one side tries to close */
+ case BOTH_SYN | (TH_FIN << 8) :
+ q->expire = time_second + dyn_ack_lifetime;
+ break;
+ case BOTH_SYN | BOTH_FIN: /* both sides closed */
+ q->expire = time_second + dyn_fin_lifetime;
+ break;
+ default:
+#if 0
+ /*
+ * reset or some invalid combination, but can also
+ * occur if we use keep-state the wrong way.
+ */
+ if ( (q->state & ((TH_RST << 8)|TH_RST)) == 0)
+ printf("invalid state: 0x%x\n", q->state);
+#endif
+ q->expire = time_second + dyn_rst_lifetime;
+ break;
+ }
+ } else if (pkt->proto == IPPROTO_UDP) {
+ q->expire = time_second + dyn_udp_lifetime;
+ } else {
+ /* other protocols */
+ q->expire = time_second + dyn_short_lifetime;
+ }
+done:
+ if (match_direction)
+ *match_direction = dir;
+ return q;
+}
+
+static void
+realloc_dynamic_table(void)
+{
+ /* try reallocation, make sure we have a power of 2 */
+
+ if ((dyn_buckets & (dyn_buckets-1)) != 0) { /* not a power of 2 */
+ dyn_buckets = curr_dyn_buckets; /* reset */
+ return;
+ }
+ curr_dyn_buckets = dyn_buckets;
+ if (ipfw_dyn_v != NULL)
+ free(ipfw_dyn_v, M_IPFW);
+ ipfw_dyn_v = malloc(curr_dyn_buckets * sizeof(ipfw_dyn_rule *),
+ M_IPFW, M_DONTWAIT | M_ZERO);
+}
+
+/**
+ * Install state of type 'type' for a dynamic session.
+ * The hash table contains two type of rules:
+ * - regular rules (O_KEEP_STATE)
+ * - rules for sessions with limited number of sess per user
+ * (O_LIMIT). When they are created, the parent is
+ * increased by 1, and decreased on delete. In this case,
+ * the third parameter is the parent rule and not the chain.
+ * - "parent" rules for the above (O_LIMIT_PARENT).
+ */
+static ipfw_dyn_rule *
+add_dyn_rule(struct ipfw_flow_id *id, u_int8_t dyn_type, struct ip_fw *rule)
+{
+ ipfw_dyn_rule *r;
+ int i;
+
+ if (ipfw_dyn_v == NULL ||
+ (dyn_count == 0 && dyn_buckets != curr_dyn_buckets)) {
+ realloc_dynamic_table();
+ if (ipfw_dyn_v == NULL)
+ return NULL; /* failed ! */
+ }
+ i = hash_packet(id);
+
+ r = malloc(sizeof *r, M_IPFW, M_DONTWAIT | M_ZERO);
+ if (r == NULL) {
+ printf ("sorry cannot allocate state\n");
+ return NULL;
+ }
+
+ /* increase refcount on parent, and set pointer */
+ if (dyn_type == O_LIMIT) {
+ ipfw_dyn_rule *parent = (ipfw_dyn_rule *)rule;
+ if ( parent->dyn_type != O_LIMIT_PARENT)
+ panic("invalid parent");
+ parent->count++;
+ r->parent = parent;
+ rule = parent->rule;
+ }
+
+ r->id = *id;
+ r->expire = time_second + dyn_syn_lifetime;
+ r->rule = rule;
+ r->dyn_type = dyn_type;
+ r->pcnt = r->bcnt = 0;
+ r->count = 0;
+
+ r->bucket = i;
+ r->next = ipfw_dyn_v[i];
+ ipfw_dyn_v[i] = r;
+ dyn_count++;
+ DEB(printf("-- add dyn entry ty %d 0x%08x %d -> 0x%08x %d, total %d\n",
+ dyn_type,
+ (r->id.src_ip), (r->id.src_port),
+ (r->id.dst_ip), (r->id.dst_port),
+ dyn_count ); )
+ return r;
+}
+
+/**
+ * lookup dynamic parent rule using pkt and rule as search keys.
+ * If the lookup fails, then install one.
+ */
+static ipfw_dyn_rule *
+lookup_dyn_parent(struct ipfw_flow_id *pkt, struct ip_fw *rule)
+{
+ ipfw_dyn_rule *q;
+ int i;
+
+ if (ipfw_dyn_v) {
+ i = hash_packet( pkt );
+ for (q = ipfw_dyn_v[i] ; q != NULL ; q=q->next)
+ if (q->dyn_type == O_LIMIT_PARENT &&
+ rule== q->rule &&
+ pkt->proto == q->id.proto &&
+ pkt->src_ip == q->id.src_ip &&
+ pkt->dst_ip == q->id.dst_ip &&
+ pkt->src_port == q->id.src_port &&
+ pkt->dst_port == q->id.dst_port) {
+ q->expire = time_second + dyn_short_lifetime;
+ DEB(printf("lookup_dyn_parent found 0x%p\n",q);)
+ return q;
+ }
+ }
+ return add_dyn_rule(pkt, O_LIMIT_PARENT, rule);
+}
+
+/**
+ * Install dynamic state for rule type cmd->o.opcode
+ *
+ * Returns 1 (failure) if state is not installed because of errors or because
+ * session limitations are enforced.
+ */
+static int
+install_state(struct ip_fw *rule, ipfw_insn_limit *cmd,
+ struct ip_fw_args *args)
+{
+ static int last_log;
+
+ ipfw_dyn_rule *q;
+
+ DEB(printf("-- install state type %d 0x%08x %u -> 0x%08x %u\n",
+ cmd->o.opcode,
+ (args->f_id.src_ip), (args->f_id.src_port),
+ (args->f_id.dst_ip), (args->f_id.dst_port) );)
+
+ q = lookup_dyn_rule(&args->f_id, NULL);
+
+ if (q != NULL) { /* should never occur */
+ if (last_log != time_second) {
+ last_log = time_second;
+ printf(" install_state: entry already present, done\n");
+ }
+ return 0;
+ }
+
+ if (dyn_count >= dyn_max)
+ /*
+ * Run out of slots, try to remove any expired rule.
+ */
+ remove_dyn_rule(NULL, (ipfw_dyn_rule *)1);
+
+ if (dyn_count >= dyn_max) {
+ if (last_log != time_second) {
+ last_log = time_second;
+ printf("install_state: Too many dynamic rules\n");
+ }
+ return 1; /* cannot install, notify caller */
+ }
+
+ switch (cmd->o.opcode) {
+ case O_KEEP_STATE: /* bidir rule */
+ add_dyn_rule(&args->f_id, O_KEEP_STATE, rule);
+ break;
+
+ case O_LIMIT: /* limit number of sessions */
+ {
+ u_int16_t limit_mask = cmd->limit_mask;
+ struct ipfw_flow_id id;
+ ipfw_dyn_rule *parent;
+
+ DEB(printf("installing dyn-limit rule %d\n", cmd->conn_limit);)
+
+ id.dst_ip = id.src_ip = 0;
+ id.dst_port = id.src_port = 0;
+ id.proto = args->f_id.proto;
+
+ if (limit_mask & DYN_SRC_ADDR)
+ id.src_ip = args->f_id.src_ip;
+ if (limit_mask & DYN_DST_ADDR)
+ id.dst_ip = args->f_id.dst_ip;
+ if (limit_mask & DYN_SRC_PORT)
+ id.src_port = args->f_id.src_port;
+ if (limit_mask & DYN_DST_PORT)
+ id.dst_port = args->f_id.dst_port;
+ parent = lookup_dyn_parent(&id, rule);
+ if (parent == NULL) {
+ printf("add parent failed\n");
+ return 1;
+ }
+ if (parent->count >= cmd->conn_limit) {
+ /*
+ * See if we can remove some expired rule.
+ */
+ remove_dyn_rule(rule, parent);
+ if (parent->count >= cmd->conn_limit) {
+ if (fw_verbose && last_log != time_second) {
+ last_log = time_second;
+ printf(
+ "drop session, too many entries\n");
+ }
+ return 1;
+ }
+ }
+ add_dyn_rule(&args->f_id, O_LIMIT, (struct ip_fw *)parent);
+ }
+ break;
+ default:
+ printf("unknown dynamic rule type %u\n", cmd->o.opcode);
+ return 1;
+ }
+ lookup_dyn_rule(&args->f_id, NULL); /* XXX just set the lifetime */
+ return 0;
+}
+
+/*
+ * sends a reject message, consuming the mbuf passed as an argument.
+ */
+static void
+send_reject(struct mbuf *m, int code, int offset, int ip_len)
+{
+ if (code != ICMP_REJECT_RST) /* Send an ICMP unreach */
+ icmp_error(m, ICMP_UNREACH, code, 0L, 0);
+ else {
+ /* XXX warning, this code writes into the mbuf */
+ struct ip *ip = mtod(m, struct ip *);
+ struct tcphdr *const tcp = L3HDR(struct tcphdr, ip);
+ struct tcpiphdr ti, *const tip = (struct tcpiphdr *) ip;
+ int hlen = ip->ip_hl << 2;
+
+ if (offset != 0 || (tcp->th_flags & TH_RST)) {
+ m_freem(m); /* free the mbuf */
+ return;
+ }
+ ti.ti_i = *((struct ipovly *) ip);
+ ti.ti_t = *tcp;
+ bcopy(&ti, ip, sizeof(ti));
+ tip->ti_seq = ntohl(tip->ti_seq);
+ tip->ti_ack = ntohl(tip->ti_ack);
+ tip->ti_len = ip_len - hlen - (tip->ti_off << 2);
+ if (tcp->th_flags & TH_ACK) {
+ tcp_respond(NULL, (void *)ip, tcp, m,
+ 0, tcp->th_ack, TH_RST);
+ } else {
+ if (tcp->th_flags & TH_SYN)
+ tip->ti_len++;
+ tcp_respond(NULL, (void *)ip, tcp, m,
+ tip->ti_seq + tip->ti_len, 0, TH_RST|TH_ACK);
+ }
+ }
+}
+
+/**
+ *
+ * Given an ip_fw *, lookup_next_rule will return a pointer
+ * to the next rule, which can be either the jump
+ * target (for skipto instructions) or the next one in the list (in
+ * all other cases including a missing jump target).
+ * The result is also written in the "next_rule" field of the rule.
+ * Backward jumps are not allowed, so start looking from the next
+ * rule...
+ *
+ * This never returns NULL -- in case we do not have an exact match,
+ * the next rule is returned. When the ruleset is changed,
+ * pointers are flushed so we are always correct.
+ */
+
+static struct ip_fw *
+lookup_next_rule(struct ip_fw *me)
+{
+ struct ip_fw *rule = NULL;
+ ipfw_insn *cmd;
+
+ /* look for action, in case it is a skipto */
+ cmd = ACTION_PTR(me);
+ if ( cmd->opcode == O_SKIPTO )
+ for (rule = me->next; rule ; rule = rule->next)
+ if (rule->rulenum >= cmd->arg1)
+ break;
+ if (rule == NULL) /* failure or not a skipto */
+ rule = me->next;
+ me->next_rule = rule;
+ return rule;
+}
+
+/*
+ * The main check routine for the firewall.
+ *
+ * All arguments are in args so we can modify them and return them
+ * back to the caller.
+ *
+ * Parameters:
+ *
+ * args->m (in/out) The packet; we set to NULL when/if we nuke it.
+ * Starts with the IP header.
+ * args->eh (in) Mac header if present, or NULL for layer3 packet.
+ * args->oif Outgoing interface, or NULL if packet is incoming.
+ * The incoming interface is in the mbuf. (in)
+ * args->divert_rule (in/out)
+ * Skip up to the first rule past this rule number;
+ * upon return, non-zero port number for divert or tee.
+ *
+ * args->rule Pointer to the last matching rule (in/out)
+ * args->next_hop Socket we are forwarding to (out).
+ * args->f_id Addresses grabbed from the packet (out)
+ *
+ * Return value:
+ *
+ * IP_FW_PORT_DENY_FLAG the packet must be dropped.
+ * 0 The packet is to be accepted and routed normally OR
+ * the packet was denied/rejected and has been dropped;
+ * in the latter case, *m is equal to NULL upon return.
+ * port Divert the packet to port, with these caveats:
+ *
+ * - If IP_FW_PORT_TEE_FLAG is set, tee the packet instead
+ * of diverting it (ie, 'ipfw tee').
+ *
+ * - If IP_FW_PORT_DYNT_FLAG is set, interpret the lower
+ * 16 bits as a dummynet pipe number instead of diverting
+ */
+
+static int
+ipfw_chk(struct ip_fw_args *args)
+{
+ /*
+ * Local variables hold state during the processing of a packet.
+ *
+ * IMPORTANT NOTE: to speed up the processing of rules, there
+ * are some assumption on the values of the variables, which
+ * are documented here. Should you change them, please check
+ * the implementation of the various instructions to make sure
+ * that they still work.
+ */
+ /*
+ * args->eh The MAC header. It is non-null for a layer2
+ * packet, it is NULL for a layer-3 packet.
+ *
+ * m | args->m Pointer to the mbuf, as received from the caller.
+ * It may change if ipfw_chk() does an m_pullup, or if it
+ * consumes the packet because it calls send_reject().
+ * XXX This has to change, so that ipfw_chk() never modifies
+ * or consumes the buffer.
+ * ip is simply an alias of the value of m, and it is kept
+ * in sync with it (the packet is supposed to start with
+ * the ip header).
+ */
+ struct mbuf *m = args->m;
+ struct ip *ip = mtod(m, struct ip *);
+
+ /*
+ * oif | args->oif If NULL, ipfw_chk has been called on the
+ * inbound path (ether_input, bdg_forward, ip_input).
+ * If non-NULL, ipfw_chk has been called on the outbound path
+ * (ether_output, ip_output).
+ */
+ struct ifnet *oif = args->oif;
+
+ struct ip_fw *f = NULL; /* matching rule */
+ int retval = 0;
+
+ /*
+ * hlen The length of the IPv4 header.
+ * hlen >0 means we have an IPv4 packet.
+ */
+ u_int hlen = 0; /* hlen >0 means we have an IP pkt */
+
+ /*
+ * offset The offset of a fragment. offset != 0 means that
+ * we have a fragment at this offset of an IPv4 packet.
+ * offset == 0 means that (if this is an IPv4 packet)
+ * this is the first or only fragment.
+ */
+ u_short offset = 0;
+
+ /*
+ * Local copies of addresses. They are only valid if we have
+ * an IP packet.
+ *
+ * proto The protocol. Set to 0 for non-ip packets,
+ * or to the protocol read from the packet otherwise.
+ * proto != 0 means that we have an IPv4 packet.
+ *
+ * src_port, dst_port port numbers, in HOST format. Only
+ * valid for TCP and UDP packets.
+ *
+ * src_ip, dst_ip ip addresses, in NETWORK format.
+ * Only valid for IPv4 packets.
+ */
+ u_int8_t proto;
+ u_int16_t src_port = 0, dst_port = 0; /* NOTE: host format */
+ struct in_addr src_ip, dst_ip; /* NOTE: network format */
+ u_int16_t ip_len=0;
+ int dyn_dir = MATCH_UNKNOWN;
+ ipfw_dyn_rule *q = NULL;
+
+ /*
+ * dyn_dir = MATCH_UNKNOWN when rules unchecked,
+ * MATCH_NONE when checked and not matched (q = NULL),
+ * MATCH_FORWARD or MATCH_REVERSE otherwise (q != NULL)
+ */
+
+ if (args->eh == NULL || /* layer 3 packet */
+ ( m->m_pkthdr.len >= sizeof(struct ip) &&
+ ntohs(args->eh->ether_type) == ETHERTYPE_IP))
+ hlen = ip->ip_hl << 2;
+
+ /*
+ * Collect parameters into local variables for faster matching.
+ */
+ if (hlen == 0) { /* do not grab addresses for non-ip pkts */
+ proto = args->f_id.proto = 0; /* mark f_id invalid */
+ goto after_ip_checks;
+ }
+
+ proto = args->f_id.proto = ip->ip_p;
+ src_ip = ip->ip_src;
+ dst_ip = ip->ip_dst;
+ if (args->eh != NULL) { /* layer 2 packets are as on the wire */
+ offset = ntohs(ip->ip_off) & IP_OFFMASK;
+ ip_len = ntohs(ip->ip_len);
+ } else {
+ offset = ip->ip_off & IP_OFFMASK;
+ ip_len = ip->ip_len;
+ }
+
+#define PULLUP_TO(len) \
+ do { \
+ if ((m)->m_len < (len)) { \
+ args->m = m = m_pullup(m, (len)); \
+ if (m == 0) \
+ goto pullup_failed; \
+ ip = mtod(m, struct ip *); \
+ } \
+ } while (0)
+
+ if (offset == 0) {
+ switch (proto) {
+ case IPPROTO_TCP:
+ {
+ struct tcphdr *tcp;
+
+ PULLUP_TO(hlen + sizeof(struct tcphdr));
+ tcp = L3HDR(struct tcphdr, ip);
+ dst_port = tcp->th_dport;
+ src_port = tcp->th_sport;
+ args->f_id.flags = tcp->th_flags;
+ }
+ break;
+
+ case IPPROTO_UDP:
+ {
+ struct udphdr *udp;
+
+ PULLUP_TO(hlen + sizeof(struct udphdr));
+ udp = L3HDR(struct udphdr, ip);
+ dst_port = udp->uh_dport;
+ src_port = udp->uh_sport;
+ }
+ break;
+
+ case IPPROTO_ICMP:
+ PULLUP_TO(hlen + 4); /* type, code and checksum. */
+ args->f_id.flags = L3HDR(struct icmp, ip)->icmp_type;
+ break;
+
+ default:
+ break;
+ }
+#undef PULLUP_TO
+ }
+
+ args->f_id.src_ip = ntohl(src_ip.s_addr);
+ args->f_id.dst_ip = ntohl(dst_ip.s_addr);
+ args->f_id.src_port = src_port = ntohs(src_port);
+ args->f_id.dst_port = dst_port = ntohs(dst_port);
+
+after_ip_checks:
+ if (args->rule) {
+ /*
+ * Packet has already been tagged. Look for the next rule
+ * to restart processing.
+ *
+ * If fw_one_pass != 0 then just accept it.
+ * XXX should not happen here, but optimized out in
+ * the caller.
+ */
+ if (fw_one_pass)
+ return 0;
+
+ f = args->rule->next_rule;
+ if (f == NULL)
+ f = lookup_next_rule(args->rule);
+ } else {
+ /*
+ * Find the starting rule. It can be either the first
+ * one, or the one after divert_rule if asked so.
+ */
+ int skipto = args->divert_rule;
+
+ f = layer3_chain;
+ if (args->eh == NULL && skipto != 0) {
+ if (skipto >= IPFW_DEFAULT_RULE)
+ return(IP_FW_PORT_DENY_FLAG); /* invalid */
+ while (f && f->rulenum <= skipto)
+ f = f->next;
+ if (f == NULL) /* drop packet */
+ return(IP_FW_PORT_DENY_FLAG);
+ }
+ }
+ args->divert_rule = 0; /* reset to avoid confusion later */
+
+ /*
+ * Now scan the rules, and parse microinstructions for each rule.
+ */
+ for (; f; f = f->next) {
+ int l, cmdlen;
+ ipfw_insn *cmd;
+ int skip_or; /* skip rest of OR block */
+
+again:
+ skip_or = 0;
+ for (l = f->cmd_len, cmd = f->cmd ; l > 0 ;
+ l -= cmdlen, cmd += cmdlen) {
+
+ /*
+ * check_body is a jump target used when we find a
+ * CHECK_STATE, and need to jump to the body of
+ * the target rule.
+ */
+
+check_body:
+ cmdlen = F_LEN(cmd);
+ /*
+ * An OR block (insn_1 || .. || insn_n) has the
+ * F_OR bit set in all but the last instruction.
+ * The first match will set "skip_or", and cause
+ * the following instructions to be skipped until
+ * past the one with the F_OR bit clear.
+ */
+ if (skip_or) { /* skip this instruction */
+ if ((cmd->len & F_OR) == 0)
+ skip_or = 0; /* next one is good */
+ continue;
+ }
+ switch (cmd->opcode) {
+ case O_NOP:
+ goto cmd_match; /* That's easy */
+
+ case O_IPPRE:
+ case O_FORWARD_MAC:
+ printf("ipfw: opcode %d unimplemented\n",
+ cmd->opcode);
+ goto cmd_fail;
+
+ case O_GID:
+ case O_UID:
+ /*
+ * We only check offset == 0 && proto != 0,
+ * as this ensures that we have an IPv4
+ * packet with the ports info.
+ */
+ if (offset!=0)
+ goto cmd_fail;
+ {
+ struct inpcbinfo *pi;
+ int wildcard;
+ struct inpcb *pcb;
+
+ if (proto == IPPROTO_TCP) {
+ wildcard = 0;
+ pi = &tcbinfo;
+ } else if (proto == IPPROTO_UDP) {
+ wildcard = 1;
+ pi = &udbinfo;
+ } else
+ goto cmd_fail;
+
+ pcb = (oif) ?
+ in_pcblookup_hash(pi,
+ dst_ip, htons(dst_port),
+ src_ip, htons(src_port),
+ wildcard, oif) :
+ in_pcblookup_hash(pi,
+ src_ip, htons(src_port),
+ dst_ip, htons(dst_port),
+ wildcard, NULL);
+
+ if (pcb == NULL || pcb->inp_socket == NULL)
+ goto cmd_fail;
+ if (cmd->opcode == O_UID) {
+#if __FreeBSD_version >= 500034
+ if (socheckuid(pcb->inp_socket,
+ (uid_t)((ipfw_insn_u32 *)cmd)->d[0]
+ ))
+#else
+ if (pcb->inp_socket->so_cred->cr_uid !=
+ (uid_t)((ipfw_insn_u32 *)cmd)->d[0])
+#endif
+ goto cmd_match;
+ } else {
+ if (groupmember(
+ (uid_t)((ipfw_insn_u32 *)cmd)->d[0],
+ pcb->inp_socket->so_cred))
+ goto cmd_match;
+ }
+ }
+ goto cmd_fail;
+
+ case O_RECV:
+ if (iface_match(m->m_pkthdr.rcvif,
+ (ipfw_insn_if *)cmd))
+ goto cmd_match;
+ goto cmd_fail;
+
+ case O_XMIT:
+ if (iface_match(oif, (ipfw_insn_if *)cmd))
+ goto cmd_match;
+ goto cmd_fail;
+
+ case O_VIA:
+ if (iface_match(oif ? oif : m->m_pkthdr.rcvif,
+ (ipfw_insn_if *)cmd))
+ goto cmd_match;
+ goto cmd_fail;
+
+ case O_MACADDR2:
+ if (args->eh != NULL) { /* have MAC header */
+ u_int32_t *want = (u_int32_t *)
+ ((ipfw_insn_mac *)cmd)->addr;
+ u_int32_t *mask = (u_int32_t *)
+ ((ipfw_insn_mac *)cmd)->mask;
+ u_int32_t *hdr = (u_int32_t *)args->eh;
+
+ if ( want[0] == (hdr[0] & mask[0]) &&
+ want[1] == (hdr[1] & mask[1]) &&
+ want[2] == (hdr[2] & mask[2]) )
+ goto cmd_match;
+ }
+ goto cmd_fail;
+
+ case O_MAC_TYPE:
+ if (args->eh != NULL) {
+ u_int16_t type =
+ ntohs(args->eh->ether_type);
+ u_int16_t *p =
+ ((ipfw_insn_u16 *)cmd)->ports;
+ int i;
+
+ for (i = cmdlen - 1; i>0; i--)
+ if (type>=p[0] && type<=p[1])
+ goto cmd_match;
+ else
+ p += 2;
+ }
+ goto cmd_fail;
+
+ case O_FRAG:
+ /* XXX check this -- MF bit ? */
+ if (hlen == 0 || offset != 0)
+ goto cmd_fail;
+ goto cmd_match;
+
+ case O_IN: /* "out" is "not in" */
+ if (oif != NULL)
+ goto cmd_fail;
+ goto cmd_match;
+
+ case O_LAYER2:
+ if (args->eh == NULL)
+ goto cmd_fail;
+ goto cmd_match;
+
+ case O_PROTO:
+ /*
+ * We do not allow an arg of 0 so the
+ * check of "proto" only suffices.
+ */
+ if (proto == cmd->arg1)
+ goto cmd_match;
+ goto cmd_fail;
+
+ case O_IP_SRC:
+ if (hlen > 0 &&
+ ((ipfw_insn_ip *)cmd)->addr.s_addr ==
+ src_ip.s_addr)
+ goto cmd_match;
+ goto cmd_fail;
+
+ case O_IP_SRC_MASK:
+ if (hlen > 0 &&
+ ((ipfw_insn_ip *)cmd)->addr.s_addr ==
+ (src_ip.s_addr &
+ ((ipfw_insn_ip *)cmd)->mask.s_addr))
+ goto cmd_match;
+ goto cmd_fail;
+
+ case O_IP_SRC_ME:
+ if (hlen == 0)
+ goto cmd_fail;
+ {
+ struct ifnet *tif;
+
+
+ INADDR_TO_IFP(src_ip, tif);
+ if (tif != NULL)
+ goto cmd_match;
+ }
+ goto cmd_fail;
+
+ case O_IP_DST_SET:
+ case O_IP_SRC_SET:
+ if (hlen == 0)
+ goto cmd_fail;
+ {
+ u_int32_t *d = (u_int32_t *)(cmd+1);
+ u_int32_t a =
+ cmd->opcode == O_IP_DST_SET ?
+ args->f_id.src_ip : args->f_id.dst_ip;
+
+ if (a < d[0])
+ goto cmd_fail;
+ a -= d[0];
+ if (a >= cmd->arg1)
+ goto cmd_fail;
+ if (d[ 1 + (a>>5)] & (1<<(a & 0x1f)) )
+ goto cmd_match;
+ }
+ goto cmd_fail;
+
+ case O_IP_DST:
+ if (hlen > 0 &&
+ ((ipfw_insn_ip *)cmd)->addr.s_addr ==
+ dst_ip.s_addr)
+ goto cmd_match;
+ goto cmd_fail;
+
+ case O_IP_DST_MASK:
+ if (hlen == 0)
+ goto cmd_fail;
+ if (((ipfw_insn_ip *)cmd)->addr.s_addr ==
+ (dst_ip.s_addr &
+ ((ipfw_insn_ip *)cmd)->mask.s_addr))
+ goto cmd_match;
+ goto cmd_fail;
+
+ case O_IP_DST_ME:
+ if (hlen == 0)
+ goto cmd_fail;
+ {
+ struct ifnet *tif;
+ INADDR_TO_IFP(dst_ip, tif);
+ if (tif != NULL)
+ goto cmd_match;
+ }
+ goto cmd_fail;
+
+ case O_IP_SRCPORT:
+ case O_IP_DSTPORT:
+ /*
+ * offset == 0 && proto != 0 is enough
+ * to guarantee that we have an IPv4
+ * packet with port info.
+ */
+ if (offset != 0)
+ goto cmd_fail;
+ if (proto==IPPROTO_UDP ||
+ proto==IPPROTO_TCP) {
+ u_int16_t port =
+ (cmd->opcode == O_IP_SRCPORT) ?
+ src_port : dst_port ;
+ u_int16_t *p =
+ ((ipfw_insn_u16 *)cmd)->ports;
+ int i;
+
+ for (i = cmdlen - 1; i>0; i--)
+ if (port>=p[0] && port<=p[1])
+ goto cmd_match;
+ else
+ p += 2;
+ }
+ goto cmd_fail;
+
+ case O_ICMPTYPE:
+ if (offset > 0 ||
+ proto != IPPROTO_ICMP ||
+ !icmptype_match(ip, (ipfw_insn_u32 *)cmd) )
+ goto cmd_fail;
+ goto cmd_match;
+
+ case O_IPOPT:
+ if (hlen == 0 ||
+ !ipopts_match(ip, cmd) )
+ goto cmd_fail;
+ goto cmd_match;
+
+ case O_IPVER:
+ if (hlen == 0 || cmd->arg1 != ip->ip_v)
+ goto cmd_fail;
+ goto cmd_match;
+
+ case O_IPTTL:
+ if (hlen == 0 || cmd->arg1 != ip->ip_ttl)
+ goto cmd_fail;
+ goto cmd_match;
+
+ case O_IPID:
+ if (hlen == 0 || cmd->arg1 != ntohs(ip->ip_id))
+ goto cmd_fail;
+ goto cmd_match;
+
+ case O_IPLEN:
+ if (hlen == 0 || cmd->arg1 != ip_len)
+ goto cmd_fail;
+ goto cmd_match;
+
+ case O_IPTOS:
+ if (hlen == 0 ||
+ !flags_match(cmd, ip->ip_tos))
+ goto cmd_fail;
+ goto cmd_match;
+
+ case O_TCPFLAGS:
+ if (proto != IPPROTO_TCP ||
+ offset > 0 ||
+ !flags_match(cmd,
+ L3HDR(struct tcphdr,ip)->th_flags))
+ goto cmd_fail;
+ goto cmd_match;
+
+ case O_TCPOPTS:
+ if (proto != IPPROTO_TCP ||
+ offset > 0 ||
+ !tcpopts_match(ip, cmd))
+ goto cmd_fail;
+ goto cmd_match;
+
+ case O_TCPSEQ:
+ if (proto != IPPROTO_TCP || offset > 0 ||
+ ((ipfw_insn_u32 *)cmd)->d[0] !=
+ L3HDR(struct tcphdr,ip)->th_seq)
+ goto cmd_fail;
+ goto cmd_match;
+
+ case O_TCPACK:
+ if (proto != IPPROTO_TCP || offset > 0 ||
+ ((ipfw_insn_u32 *)cmd)->d[0] !=
+ L3HDR(struct tcphdr,ip)->th_ack)
+ goto cmd_fail;
+ goto cmd_match;
+
+ case O_TCPWIN:
+ if (proto != IPPROTO_TCP || offset > 0 ||
+ cmd->arg1 !=
+ L3HDR(struct tcphdr,ip)->th_win)
+ goto cmd_fail;
+ goto cmd_match;
+
+ case O_ESTAB:
+ if (proto != IPPROTO_TCP || offset > 0)
+ goto cmd_fail;
+
+ /* reject packets which have SYN only */
+ if ((L3HDR(struct tcphdr,ip)->th_flags &
+ (TH_RST | TH_ACK | TH_SYN)) == TH_SYN)
+ goto cmd_fail;
+ goto cmd_match;
+
+ case O_LOG:
+ ipfw_log(f, hlen, args->eh, m, oif);
+ goto cmd_match;
+
+ case O_PROB: /* XXX check */
+ if (random() < ((ipfw_insn_u32 *)cmd)->d[0] )
+ goto cmd_match;
+ goto cmd_fail;
+
+ case O_LIMIT:
+ case O_KEEP_STATE:
+ if (install_state(f,
+ (ipfw_insn_limit *)cmd, args))
+ goto deny; /* error/limit violation */
+ goto cmd_match;
+
+ case O_PROBE_STATE:
+ case O_CHECK_STATE:
+ /*
+ * dynamic rules are checked at the first
+ * keep-state or check-state occurrence.
+ * The compiler introduces a probe-state
+ * instruction for us when we have a
+ * keep-state (because probe-state needs
+ * to be run first).
+ */
+ if (dyn_dir == MATCH_UNKNOWN) {
+ q = lookup_dyn_rule(&args->f_id,
+ &dyn_dir);
+ if (q != NULL) {
+ f = q->rule;
+ q->pcnt++;
+ q->bcnt += ip_len;
+ /* go to ACTION */
+ cmd = ACTION_PTR(f);
+ l = f->cmd_len - f->act_ofs;
+ goto check_body;
+ }
+ }
+ if (cmd->opcode == O_CHECK_STATE)
+ goto next_rule;
+ else
+ goto cmd_match;
+
+ case O_ACCEPT:
+ retval = 0; /* accept */
+ goto accept;
+
+ case O_PIPE:
+ case O_QUEUE:
+ args->rule = f; /* report matching rule */
+ retval = cmd->arg1 | IP_FW_PORT_DYNT_FLAG;
+ goto accept;
+
+ case O_DIVERT:
+ case O_TEE:
+ if (args->eh) /* not on layer 2 */
+ goto cmd_fail;
+ args->divert_rule = f->rulenum;
+ if (cmd->opcode == O_DIVERT)
+ retval = cmd->arg1;
+ else
+ retval = cmd->arg1|IP_FW_PORT_TEE_FLAG;
+ goto accept;
+
+ case O_COUNT:
+ case O_SKIPTO:
+ f->pcnt++; /* update stats */
+ f->bcnt += ip_len;
+ f->timestamp = time_second;
+ if (cmd->opcode == O_COUNT)
+ goto next_rule;
+ /* handle skipto */
+ if (f->next_rule == NULL)
+ lookup_next_rule(f);
+ f = f->next_rule;
+ goto again;
+
+ case O_REJECT:
+ /*
+ * Drop the packet and send a reject notice
+ * if the packet is not ICMP (or is an ICMP
+ * query), and it is not multicast/broadcast.
+ */
+ if (hlen > 0 &&
+ (proto != IPPROTO_ICMP ||
+ is_icmp_query(ip)) &&
+ !(m->m_flags & (M_BCAST|M_MCAST)) &&
+ !IN_MULTICAST(dst_ip.s_addr)) {
+ send_reject(m,cmd->arg1,offset,ip_len);
+ args->m = m = NULL;
+ }
+ goto deny;
+
+ case O_FORWARD_IP:
+ if (args->eh) /* not valid on layer2 pkts */
+ goto cmd_fail;
+ if (!q || dyn_dir == MATCH_FORWARD)
+ args->next_hop =
+ &((ipfw_insn_sa *)cmd)->sa;
+ retval = 0;
+ goto accept;
+
+ case O_DENY:
+ goto deny;
+
+ default:
+ panic("-- unknown opcode %d\n", cmd->opcode);
+ }
+ panic("ipfw_chk: end of inner loop");
+
+ /*
+ * This code is a bit spaghetti, but we have
+ * 4 cases to handle:
+ * INSN FAIL, no F_NOT --> insn_fail
+ * INSN FAIL, but we have F_NOT --> cmd_success
+ * INSN MATCH, no F_NOT --> cmd_success
+ * INSN MATCH, but we have F_NOT --> insn_fail
+ *
+ * after this:
+ * cmd_success, F_OR --> set skip_or
+ * cmd_success, not F_OR --> try next insn
+ * insn_fail, F_OR --> try next insn
+ * insn_fail, not F_OR --> rule does not match
+ */
+cmd_fail:
+ if (cmd->len & F_NOT) /* NOT fail is a success */
+ goto cmd_success;
+ else
+ goto insn_fail;
+
+cmd_match:
+ if (cmd->len & F_NOT) { /* NOT match is a failure. */
+insn_fail:
+ if (cmd->len & F_OR) /* If an or block */
+ continue; /* try next insn */
+ else
+ break; /* otherwise next rule */
+ }
+
+cmd_success:
+ if (cmd->len & F_OR)
+ skip_or = 1;
+ } /* end of inner for, scan opcodes */
+
+next_rule: /* try next rule */
+
+ } /* end of outer for, scan rules */
+
+deny:
+ retval = IP_FW_PORT_DENY_FLAG;
+
+accept:
+ /* Update statistics */
+ f->pcnt++;
+ f->bcnt += ip_len;
+ f->timestamp = time_second;
+ return retval;
+
+pullup_failed:
+ if (fw_verbose)
+ printf("pullup failed\n");
+ return(IP_FW_PORT_DENY_FLAG);
+}
+
+#if 0 /* XXX old instructions not implemented yet XXX */
+bogusfrag:
+ if (fw_verbose) {
+ if (*m != NULL)
+ ipfw_report(NULL, ip, ip_off, ip_len, (*m)->m_pkthdr.rcvif, oif);
+ }
+ return(IP_FW_PORT_DENY_FLAG);
+
+ if (f->fw_ipflg & IP_FW_IF_IPPRE &&
+ (f->fw_iptos & 0xe0) != (ip->ip_tos & 0xe0))
+ continue;
+
+#endif /* XXX old instructions not implemented yet */
+
+/*
+ * When a rule is added/deleted, clear the next_rule pointers in all rules.
+ * These will be reconstructed on the fly as packets are matched.
+ * Must be called at splimp().
+ */
+static void
+flush_rule_ptrs(void)
+{
+ struct ip_fw *rule;
+
+ for (rule = layer3_chain; rule; rule = rule->next)
+ rule->next_rule = NULL;
+}
+
+/*
+ * When pipes/queues are deleted, clear the "pipe_ptr" pointer to a given
+ * pipe/queue, or to all of them (match == NULL).
+ * Must be called at splimp().
+ */
+void
+flush_pipe_ptrs(struct dn_flow_set *match)
+{
+ struct ip_fw *rule;
+
+ for (rule = layer3_chain; rule; rule = rule->next) {
+ ipfw_insn_pipe *cmd = (ipfw_insn_pipe *)ACTION_PTR(rule);
+
+ if (cmd->o.opcode != O_PIPE && cmd->o.opcode != O_QUEUE)
+ continue;
+
+ if (match == NULL || cmd->pipe_ptr == match)
+ cmd->pipe_ptr = NULL;
+ }
+}
+
+/*
+ * Add a new rule to the list. Copy the rule into a malloc'ed area, then
+ * possibly create a rule number and add the rule to the list.
+ * Update the rule_number in the input struct so the caller knows it as well.
+ */
+static int
+add_rule(struct ip_fw **head, struct ip_fw *input_rule)
+{
+ struct ip_fw *rule, *f, *prev;
+ int s;
+ int l = RULESIZE(input_rule);
+
+ if (*head == NULL && input_rule->rulenum != IPFW_DEFAULT_RULE)
+ return (EINVAL);
+
+ rule = malloc(l, M_IPFW, M_DONTWAIT | M_ZERO);
+ if (rule == NULL)
+ return (ENOSPC);
+
+ bcopy(input_rule, rule, l);
+
+ rule->next = NULL;
+ rule->next_rule = NULL;
+
+ rule->pcnt = 0;
+ rule->bcnt = 0;
+ rule->timestamp = 0;
+
+ s = splimp();
+
+ if (*head == NULL) { /* default rule */
+ *head = rule;
+ goto done;
+ }
+
+ /*
+ * If rulenum is 0, find highest numbered rule before the
+ * default rule, and add autoinc_step
+ */
+ if (autoinc_step < 1)
+ autoinc_step = 1;
+ else if (autoinc_step > 1000)
+ autoinc_step = 1000;
+ if (rule->rulenum == 0) {
+ /*
+ * locate the highest numbered rule before default
+ */
+ for (f = *head; f; f = f->next) {
+ if (f->rulenum == IPFW_DEFAULT_RULE)
+ break;
+ rule->rulenum = f->rulenum;
+ }
+ if (rule->rulenum < IPFW_DEFAULT_RULE - autoinc_step)
+ rule->rulenum += autoinc_step;
+ input_rule->rulenum = rule->rulenum;
+ }
+
+ /*
+ * Now insert the new rule in the right place in the sorted list.
+ */
+ for (prev = NULL, f = *head; f; prev = f, f = f->next) {
+ if (f->rulenum > rule->rulenum) { /* found the location */
+ if (prev) {
+ rule->next = f;
+ prev->next = rule;
+ } else { /* head insert */
+ rule->next = *head;
+ *head = rule;
+ }
+ break;
+ }
+ }
+ flush_rule_ptrs();
+done:
+ static_count++;
+ static_len += l;
+ splx(s);
+ DEB(printf("++ installed rule %d, static count now %d\n",
+ rule->rulenum, static_count);)
+ return (0);
+}
+
+/**
+ * Free storage associated with a static rule (including derived
+ * dynamic rules).
+ * The caller is in charge of clearing rule pointers to avoid
+ * dangling pointers.
+ * @return a pointer to the next entry.
+ * Arguments are not checked, so they better be correct.
+ * Must be called at splimp().
+ */
+static struct ip_fw *
+delete_rule(struct ip_fw **head, struct ip_fw *prev, struct ip_fw *rule)
+{
+ struct ip_fw *n;
+ int l = RULESIZE(rule);
+
+ n = rule->next;
+ remove_dyn_rule(rule, NULL /* force removal */);
+ if (prev == NULL)
+ *head = n;
+ else
+ prev->next = n;
+ static_count--;
+ static_len -= l;
+
+ if (DUMMYNET_LOADED)
+ ip_dn_ruledel_ptr(rule);
+ free(rule, M_IPFW);
+ return n;
+}
+
+/*
+ * Deletes all rules from a chain (including the default rule
+ * if the second argument is set).
+ * Must be called at splimp().
+ */
+static void
+free_chain(struct ip_fw **chain, int kill_default)
+{
+ struct ip_fw *rule;
+
+ flush_rule_ptrs(); /* more efficient to do outside the loop */
+
+ while ( (rule = *chain) != NULL &&
+ (kill_default || rule->rulenum != IPFW_DEFAULT_RULE) )
+ delete_rule(chain, NULL, rule);
+}
+
+/**
+ * Remove all rules with given number.
+ */
+static int
+del_entry(struct ip_fw **chain, u_short rulenum)
+{
+ struct ip_fw *prev, *rule;
+ int s;
+
+ if (rulenum == IPFW_DEFAULT_RULE)
+ return EINVAL;
+
+ /*
+ * locate first rule to delete
+ */
+ for (prev = NULL, rule = *chain; rule && rule->rulenum < rulenum;
+ prev = rule, rule = rule->next)
+ ;
+ if (rule->rulenum != rulenum)
+ return EINVAL;
+
+ s = splimp(); /* no access to rules while removing */
+ flush_rule_ptrs(); /* more efficient to do outside the loop */
+ /*
+ * prev remains the same throughout the cycle
+ */
+ while (rule && rule->rulenum == rulenum)
+ rule = delete_rule(chain, prev, rule);
+ splx(s);
+ return 0;
+}
+
+/*
+ * Clear counters for a specific rule.
+ */
+static void
+clear_counters(struct ip_fw *rule, int log_only)
+{
+ ipfw_insn_log *l = (ipfw_insn_log *)ACTION_PTR(rule);
+
+ if (log_only == 0) {
+ rule->bcnt = rule->pcnt = 0;
+ rule->timestamp = 0;
+ }
+ if (l->o.opcode == O_LOG)
+ l->log_left = l->max_log;
+}
+
+/**
+ * Reset some or all counters on firewall rules.
+ * @arg frwl is null to clear all entries, or contains a specific
+ * rule number.
+ * @arg log_only is 1 if we only want to reset logs, zero otherwise.
+ */
+static int
+zero_entry(int rulenum, int log_only)
+{
+ struct ip_fw *rule;
+ int s;
+ char *msg;
+
+ if (rulenum == 0) {
+ s = splimp();
+ norule_counter = 0;
+ for (rule = layer3_chain; rule; rule = rule->next)
+ clear_counters(rule, log_only);
+ splx(s);
+ msg = log_only ? "ipfw: All logging counts reset.\n" :
+ "ipfw: Accounting cleared.\n";
+ } else {
+ int cleared = 0;
+ /*
+ * We can have multiple rules with the same number, so we
+ * need to clear them all.
+ */
+ for (rule = layer3_chain; rule; rule = rule->next)
+ if (rule->rulenum == rulenum) {
+ s = splimp();
+ while (rule && rule->rulenum == rulenum) {
+ clear_counters(rule, log_only);
+ rule = rule->next;
+ }
+ splx(s);
+ cleared = 1;
+ break;
+ }
+ if (!cleared) /* we did not find any matching rules */
+ return (EINVAL);
+ msg = log_only ? "ipfw: Entry %d logging count reset.\n" :
+ "ipfw: Entry %d cleared.\n";
+ }
+ if (fw_verbose)
+ log(LOG_SECURITY | LOG_NOTICE, msg, rulenum);
+ return (0);
+}
+
+/*
+ * Check validity of the structure before insert.
+ * Fortunately rules are simple, so this mostly need to check rule sizes.
+ */
+static int
+check_ipfw_struct(struct ip_fw *rule, int size)
+{
+ int l, cmdlen = 0;
+ int have_action=0;
+ ipfw_insn *cmd;
+
+ if (size < sizeof(*rule)) {
+ printf("kipfw: rule too short\n");
+ return (EINVAL);
+ }
+ /* first, check for valid size */
+ l = RULESIZE(rule);
+ if (l != size) {
+ printf("kipfw: size mismatch (have %d want %d)\n", size, l);
+ return (EINVAL);
+ }
+ /*
+ * Now go for the individual checks. Very simple ones, basically only
+ * instruction sizes.
+ */
+ for (l = rule->cmd_len, cmd = rule->cmd ;
+ l > 0 ; l -= cmdlen, cmd += cmdlen) {
+ cmdlen = F_LEN(cmd);
+ if (cmdlen > l) {
+ printf("kipfw: opcode %d size truncated\n",
+ cmd->opcode);
+ return EINVAL;
+ }
+ DEB(printf("kipfw: opcode %d\n", cmd->opcode);)
+ switch (cmd->opcode) {
+ case O_NOP:
+ case O_PROBE_STATE:
+ case O_KEEP_STATE:
+ case O_PROTO:
+ case O_IP_SRC_ME:
+ case O_IP_DST_ME:
+ case O_LAYER2:
+ case O_IN:
+ case O_FRAG:
+ case O_IPOPT:
+ case O_IPLEN:
+ case O_IPID:
+ case O_IPPRE:
+ case O_IPTOS:
+ case O_IPTTL:
+ case O_IPVER:
+ case O_TCPWIN:
+ case O_TCPFLAGS:
+ case O_TCPOPTS:
+ case O_ESTAB:
+ if (cmdlen != F_INSN_SIZE(ipfw_insn))
+ goto bad_size;
+ break;
+
+ case O_UID:
+ case O_GID:
+ case O_IP_SRC:
+ case O_IP_DST:
+ case O_TCPSEQ:
+ case O_TCPACK:
+ case O_PROB:
+ case O_ICMPTYPE:
+ if (cmdlen != F_INSN_SIZE(ipfw_insn_u32))
+ goto bad_size;
+ break;
+
+ case O_LIMIT:
+ if (cmdlen != F_INSN_SIZE(ipfw_insn_limit))
+ goto bad_size;
+ break;
+
+ case O_LOG:
+ if (cmdlen != F_INSN_SIZE(ipfw_insn_log))
+ goto bad_size;
+
+ ((ipfw_insn_log *)cmd)->log_left =
+ ((ipfw_insn_log *)cmd)->max_log;
+
+ break;
+
+ case O_IP_SRC_MASK:
+ case O_IP_DST_MASK:
+ if (cmdlen != F_INSN_SIZE(ipfw_insn_ip))
+ goto bad_size;
+ if (((ipfw_insn_ip *)cmd)->mask.s_addr == 0) {
+ printf("kipfw: opcode %d, useless rule\n",
+ cmd->opcode);
+ return EINVAL;
+ }
+ break;
+
+ case O_IP_SRC_SET:
+ case O_IP_DST_SET:
+ if (cmd->arg1 == 0 || cmd->arg1 > 256) {
+ printf("kipfw: invalid set size %d\n",
+ cmd->arg1);
+ return EINVAL;
+ }
+ if (cmdlen != F_INSN_SIZE(ipfw_insn_u32) +
+ (cmd->arg1+31)/32 )
+ goto bad_size;
+ break;
+
+ case O_MACADDR2:
+ if (cmdlen != F_INSN_SIZE(ipfw_insn_mac))
+ goto bad_size;
+ break;
+
+ case O_MAC_TYPE:
+ case O_IP_SRCPORT:
+ case O_IP_DSTPORT: /* XXX artificial limit, 15 port pairs */
+ if (cmdlen < 2 || cmdlen > 15)
+ goto bad_size;
+ break;
+
+ case O_RECV:
+ case O_XMIT:
+ case O_VIA:
+ if (cmdlen != F_INSN_SIZE(ipfw_insn_if))
+ goto bad_size;
+ break;
+
+ case O_PIPE:
+ case O_QUEUE:
+ if (cmdlen != F_INSN_SIZE(ipfw_insn_pipe))
+ goto bad_size;
+ goto check_action;
+
+ case O_FORWARD_IP: /* XXX no! */
+ if (cmdlen != F_INSN_SIZE(ipfw_insn_sa))
+ goto bad_size;
+ goto check_action;
+
+ case O_FORWARD_MAC: /* XXX no! */
+ case O_CHECK_STATE:
+ case O_COUNT:
+ case O_ACCEPT:
+ case O_DENY:
+ case O_REJECT:
+ case O_SKIPTO:
+ case O_DIVERT:
+ case O_TEE:
+ if (cmdlen != F_INSN_SIZE(ipfw_insn))
+ goto bad_size;
+check_action:
+ if (have_action) {
+ printf("kipfw: opcode %d, multiple actions"
+ " not allowed\n",
+ cmd->opcode);
+ return EINVAL;
+ }
+ have_action = 1;
+ if (l != cmdlen) {
+ printf("kipfw: opcode %d, action must be"
+ " last opcode\n",
+ cmd->opcode);
+ return EINVAL;
+ }
+ break;
+ default:
+ printf("kipfw: opcode %d, unknown opcode\n",
+ cmd->opcode);
+ return EINVAL;
+ }
+ }
+ if (have_action == 0) {
+ printf("kipfw: missing action\n");
+ return EINVAL;
+ }
+ return 0;
+
+bad_size:
+ printf("kipfw: opcode %d size %d wrong\n",
+ cmd->opcode, cmdlen);
+ return EINVAL;
+}
+
+
+/**
+ * {set|get}sockopt parser.
+ */
+static int
+ipfw_ctl(struct sockopt *sopt)
+{
+ int error, s, rulenum;
+ size_t size;
+ struct ip_fw *bp , *buf, *rule;
+
+ static u_int32_t rule_buf[255]; /* we copy the data here */
+
+ /*
+ * Disallow modifications in really-really secure mode, but still allow
+ * the logging counters to be reset.
+ */
+ if (sopt->sopt_name == IP_FW_ADD ||
+ (sopt->sopt_dir == SOPT_SET && sopt->sopt_name != IP_FW_RESETLOG)) {
+#if __FreeBSD_version >= 500034
+ error = securelevel_ge(sopt->sopt_td->td_ucred, 3);
+ if (error)
+ return (error);
+#else /* FreeBSD 4.x */
+ if (securelevel >= 3)
+ return (EPERM);
+#endif
+ }
+
+ error = 0;
+
+ switch (sopt->sopt_name) {
+ case IP_FW_GET:
+ /*
+ * pass up a copy of the current rules. Static rules
+ * come first (the last of which has number IPFW_DEFAULT_RULE),
+ * followed by a possibly empty list of dynamic rule.
+ * The last dynamic rule has NULL in the "next" field.
+ */
+ s = splimp();
+ size = static_len; /* size of static rules */
+ if (ipfw_dyn_v) /* add size of dyn.rules */
+ size += (dyn_count * sizeof(ipfw_dyn_rule));
+
+ /*
+ * XXX todo: if the user passes a short length just to know
+ * how much room is needed, do not bother filling up the
+ * buffer, just jump to the sooptcopyout.
+ */
+ buf = malloc(size, M_TEMP, M_WAITOK);
+ if (buf == 0) {
+ splx(s);
+ error = ENOBUFS;
+ break;
+ }
+
+ bp = buf;
+ for (rule = layer3_chain; rule ; rule = rule->next) {
+ int i = RULESIZE(rule);
+ bcopy(rule, bp, i);
+ bp = (struct ip_fw *)((char *)bp + i);
+ }
+ if (ipfw_dyn_v) {
+ int i;
+ ipfw_dyn_rule *p, *dst, *last = NULL;
+
+ dst = (ipfw_dyn_rule *)bp;
+ for (i = 0 ; i < curr_dyn_buckets ; i++ )
+ for ( p = ipfw_dyn_v[i] ; p != NULL ;
+ p = p->next, dst++ ) {
+ bcopy(p, dst, sizeof *p);
+ (int)dst->rule = p->rule->rulenum ;
+ /*
+ * store a non-null value in "next".
+ * The userland code will interpret a
+ * NULL here as a marker
+ * for the last dynamic rule.
+ */
+ dst->next = dst ;
+ last = dst ;
+ dst->expire =
+ TIME_LEQ(dst->expire, time_second) ?
+ 0 : dst->expire - time_second ;
+ }
+ if (last != NULL) /* mark last dynamic rule */
+ last->next = NULL;
+ }
+ splx(s);
+
+ error = sooptcopyout(sopt, buf, size);
+ free(buf, M_TEMP);
+ break;
+
+ case IP_FW_FLUSH:
+ /*
+ * Normally we cannot release the lock on each iteration.
+ * We could do it here only because we start from the head all
+ * the times so there is no risk of missing some entries.
+ * On the other hand, the risk is that we end up with
+ * a very inconsistent ruleset, so better keep the lock
+ * around the whole cycle.
+ *
+ * XXX this code can be improved by resetting the head of
+ * the list to point to the default rule, and then freeing
+ * the old list without the need for a lock.
+ */
+
+ s = splimp();
+ free_chain(&layer3_chain, 0 /* keep default rule */);
+ splx(s);
+ break;
+
+ case IP_FW_ADD:
+ rule = (struct ip_fw *)rule_buf; /* XXX do a malloc */
+ error = sooptcopyin(sopt, rule, sizeof(rule_buf),
+ sizeof(struct ip_fw) );
+ size = sopt->sopt_valsize;
+ if (error || (error = check_ipfw_struct(rule, size)))
+ break;
+
+ error = add_rule(&layer3_chain, rule);
+ size = RULESIZE(rule);
+ if (!error && sopt->sopt_dir == SOPT_GET)
+ error = sooptcopyout(sopt, rule, size);
+ break;
+
+ case IP_FW_DEL: /* argument is an int, the rule number */
+ error = sooptcopyin(sopt, &rulenum, sizeof(int), sizeof(int));
+ if (error)
+ break;
+ if (rulenum == IPFW_DEFAULT_RULE) {
+ if (fw_debug)
+ printf("ipfw: can't delete rule %u\n",
+ (unsigned)IPFW_DEFAULT_RULE);
+ error = EINVAL;
+ } else
+ error = del_entry(&layer3_chain, rulenum);
+ break;
+
+ case IP_FW_ZERO:
+ case IP_FW_RESETLOG: /* argument is an int, the rule number */
+ rulenum=0;
+
+ if (sopt->sopt_val != 0) {
+ error = sooptcopyin(sopt, &rulenum,
+ sizeof(int), sizeof(int));
+ if (error)
+ break;
+ }
+ error = zero_entry(rulenum, sopt->sopt_name == IP_FW_RESETLOG);
+ break;
+
+ default:
+ printf("ipfw_ctl invalid option %d\n", sopt->sopt_name);
+ error = EINVAL;
+ }
+
+ return (error);
+}
+
+/**
+ * dummynet needs a reference to the default rule, because rules can be
+ * deleted while packets hold a reference to them. When this happens,
+ * dummynet changes the reference to the default rule (it could well be a
+ * NULL pointer, but this way we do not need to check for the special
+ * case, plus here he have info on the default behaviour).
+ */
+struct ip_fw *ip_fw_default_rule;
+
+static void
+ipfw_init(void)
+{
+ struct ip_fw default_rule;
+
+ ip_fw_chk_ptr = ipfw_chk;
+ ip_fw_ctl_ptr = ipfw_ctl;
+ layer3_chain = NULL;
+
+ bzero(&default_rule, sizeof default_rule);
+
+ default_rule.act_ofs = 0;
+ default_rule.rulenum = IPFW_DEFAULT_RULE;
+ default_rule.cmd_len = 1;
+
+ default_rule.cmd[0].len = 1;
+ default_rule.cmd[0].opcode =
+#ifdef IPFIREWALL_DEFAULT_TO_ACCEPT
+ 1 ? O_ACCEPT :
+#endif
+ O_DENY;
+
+ add_rule(&layer3_chain, &default_rule);
+
+ ip_fw_default_rule = layer3_chain;
+ printf("IP packet filtering initialized, divert %s, "
+ "rule-based forwarding %s, default to %s, logging ",
+#ifdef IPDIVERT
+ "enabled",
+#else
+ "disabled",
+#endif
+ "enabled",
+ default_rule.cmd[0].opcode == O_ACCEPT ? "accept" : "deny");
+
+#ifdef IPFIREWALL_VERBOSE
+ fw_verbose = 1;
+#endif
+#ifdef IPFIREWALL_VERBOSE_LIMIT
+ verbose_limit = IPFIREWALL_VERBOSE_LIMIT;
+#endif
+ printf("logging ");
+ if (fw_verbose == 0)
+ printf("disabled\n");
+ else if (verbose_limit == 0)
+ printf("unlimited\n");
+ else
+ printf("limited to %d packets/entry by default\n",
+ verbose_limit);
+}
+
+static int
+ipfw_modevent(module_t mod, int type, void *unused)
+{
+ int s;
+ int err = 0;
+
+ switch (type) {
+ case MOD_LOAD:
+ s = splimp();
+ if (IPFW_LOADED) {
+ splx(s);
+ printf("IP firewall already loaded\n");
+ err = EEXIST;
+ } else {
+ ipfw_init();
+ splx(s);
+ }
+ break;
+
+ case MOD_UNLOAD:
+#if !defined(KLD_MODULE)
+ printf("ipfw statically compiled, cannot unload\n");
+ err = EBUSY;
+#else
+ s = splimp();
+ ip_fw_chk_ptr = NULL;
+ ip_fw_ctl_ptr = NULL;
+ free_chain(&layer3_chain, 1 /* kill default rule */);
+ splx(s);
+ printf("IP firewall unloaded\n");
+#endif
+ break;
+ default:
+ break;
+ }
+ return err;
+}
+
+static moduledata_t ipfwmod = {
+ "ipfw",
+ ipfw_modevent,
+ 0
+};
+DECLARE_MODULE(ipfw, ipfwmod, SI_SUB_PSEUDO, SI_ORDER_ANY);
+MODULE_VERSION(ipfw, 1);
diff --git a/sys/netinet/libalias/alias_db.c b/sys/netinet/libalias/alias_db.c
index 52384b3..f5b0405 100644
--- a/sys/netinet/libalias/alias_db.c
+++ b/sys/netinet/libalias/alias_db.c
@@ -2641,6 +2641,82 @@ PacketAliasCheckNewLink(void)
#include <string.h>
#include <err.h>
+#define NEW_IPFW 1 /* use new ipfw code */
+#ifdef NEW_IPFW
+/*
+ * A function to fill simple commands of size 1.
+ * Existing flags are preserved.
+ */
+static void
+fill_cmd(ipfw_insn *cmd, enum ipfw_opcodes opcode, int flags, u_int16_t arg)
+{
+ cmd->opcode = opcode;
+ cmd->len = ((cmd->len | flags) & (F_NOT | F_OR)) | 1;
+ cmd->arg1 = arg;
+}
+
+/*
+ * helper function, updates the pointer to cmd with the length
+ * of the current command, and also cleans up the first word of
+ * the new command in case it has been clobbered before.
+ */
+static ipfw_insn *
+next_cmd(ipfw_insn *cmd)
+{
+ cmd += F_LEN(cmd);
+ bzero(cmd, sizeof(*cmd));
+ return cmd;
+}
+
+static void
+fill_ip(ipfw_insn_ip *cmd, enum ipfw_opcodes opcode, u_int32_t addr)
+{
+ cmd->o.opcode = opcode;
+ cmd->o.len = F_INSN_SIZE(ipfw_insn_u32);
+ cmd->addr.s_addr = addr;
+}
+
+static void
+fill_one_port(ipfw_insn_u16 *cmd, enum ipfw_opcodes opcode, u_int16_t port)
+{
+ cmd->o.opcode = opcode;
+ cmd->o.len = F_INSN_SIZE(ipfw_insn_u16);
+ cmd->ports[0] = cmd->ports[1] = port;
+}
+
+static int
+fill_rule(void *buf, int bufsize, int rulenum,
+ enum ipfw_opcodes action, int proto,
+ struct in_addr sa, u_int16_t sp, struct in_addr da, u_int32_t dp)
+{
+ struct ip_fw *rule = (struct ip_fw *)buf;
+ ipfw_insn *cmd = (ipfw_insn *)rule->cmd;
+
+ bzero(buf, bufsize);
+ rule->rulenum = rulenum;
+
+ fill_cmd(cmd, O_PROTO, 0, proto);
+ cmd = next_cmd(cmd);
+
+ fill_ip((ipfw_insn_ip *)cmd, O_IP_SRC, sa.s_addr);
+ cmd = next_cmd(cmd);
+
+ fill_one_port((ipfw_insn_u16 *)cmd, O_IP_SRCPORT, sp);
+ cmd = next_cmd(cmd);
+
+ fill_ip((ipfw_insn_ip *)cmd, O_IP_DST, da.s_addr);
+ cmd = next_cmd(cmd);
+
+ fill_one_port((ipfw_insn_u16 *)cmd, O_IP_DSTPORT, dp);
+ cmd = next_cmd(cmd);
+
+ fill_cmd(cmd, O_ACCEPT, 0, 0);
+ cmd = next_cmd(cmd);
+
+ return ((void *)cmd - buf);
+}
+#endif /* NEW_IPFW */
+
static void ClearAllFWHoles(void);
static int fireWallBaseNum; /* The first firewall entry free for our use */
@@ -2724,6 +2800,35 @@ PunchFWHole(struct alias_link *link) {
/* Start next search at next position */
fireWallActiveNum = fwhole+1;
+#ifdef NEW_IPFW
+ if (GetOriginalPort(link) != 0 && GetDestPort(link) != 0) {
+ /*
+ * generate two rules of the form
+ *
+ * add fwhole accept tcp from OAddr OPort to DAddr DPort
+ * add fwhole accept tcp from DAddr DPort to OAddr OPort
+ */
+ u_int32_t rulebuf[255];
+ int i;
+
+ i = fill_rule(rulebuf, sizeof(rulebuf), fwhole,
+ O_ACCEPT, IPPROTO_TCP,
+ GetOriginalAddress(link), ntohs(GetOriginalPort(link)),
+ GetDestAddress(link), ntohs(GetDestPort(link)) );
+ r = setsockopt(fireWallFD, IPPROTO_IP, IP_FW_ADD, rulebuf, i);
+ if (r)
+ err(1, "alias punch inbound(1) setsockopt(IP_FW_ADD)");
+
+ i = fill_rule(rulebuf, sizeof(rulebuf), fwhole,
+ O_ACCEPT, IPPROTO_TCP,
+ GetDestAddress(link), ntohs(GetDestPort(link)),
+ GetOriginalAddress(link), ntohs(GetOriginalPort(link)) );
+ r = setsockopt(fireWallFD, IPPROTO_IP, IP_FW_ADD, rulebuf, i);
+ if (r)
+ err(1, "alias punch inbound(2) setsockopt(IP_FW_ADD)");
+ }
+#else /* !NEW_IPFW old code to generate ipfw rule */
+
/* Build generic part of the two rules */
rule.fw_number = fwhole;
IP_FW_SETNSRCP(&rule, 1); /* Number of source ports. */
@@ -2759,6 +2864,7 @@ PunchFWHole(struct alias_link *link) {
err(1, "alias punch inbound(2) setsockopt(IP_FW_ADD)");
#endif
}
+#endif /* !NEW_IPFW */
/* Indicate hole applied */
link->data.tcp->fwhole = fwhole;
fw_setfield(fireWallField, fwhole);
@@ -2770,6 +2876,10 @@ static void
ClearFWHole(struct alias_link *link) {
if (link->link_type == LINK_TCP) {
int fwhole = link->data.tcp->fwhole; /* Where is the firewall hole? */
+#ifdef NEW_IPFW
+ while (!setsockopt(fireWallFD, IPPROTO_IP, IP_FW_DEL, &fwhole, sizeof fwhole))
+ ;
+#else /* !NEW_IPFW */
struct ip_fw rule;
if (fwhole < 0)
@@ -2779,7 +2889,9 @@ ClearFWHole(struct alias_link *link) {
rule.fw_number = fwhole;
while (!setsockopt(fireWallFD, IPPROTO_IP, IP_FW_DEL, &rule, sizeof rule))
;
+#endif /* !NEW_IPFW */
fw_clrfield(fireWallField, fwhole);
+
link->data.tcp->fwhole = -1;
}
}
@@ -2795,9 +2907,15 @@ ClearAllFWHoles(void) {
memset(&rule, 0, sizeof rule);
for (i = fireWallBaseNum; i < fireWallBaseNum + fireWallNumNums; i++) {
+#ifdef NEW_IPFW
+ int r = i;
+ while (!setsockopt(fireWallFD, IPPROTO_IP, IP_FW_DEL, &r, sizeof r))
+ ;
+#else /* !NEW_IPFW */
rule.fw_number = i;
while (!setsockopt(fireWallFD, IPPROTO_IP, IP_FW_DEL, &rule, sizeof rule))
;
+#endif /* NEW_IPFW */
}
memset(fireWallField, 0, fireWallNumNums);
}
OpenPOWER on IntegriCloud