freebsd-dev/sys/netinet/ip_fw.h

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/*
The new ipfw code. This code makes use of variable-size kernel representation of rules (exactly the same concept of BPF instructions, as used in the BSDI's firewall), which makes firewall operation a lot faster, and the code more readable and easier to extend and debug. The interface with the rest of the system is unchanged, as witnessed by this commit. The only extra kernel files that I am touching are if_fw.h and ip_dummynet.c, which is quite tied to ipfw. In userland I only had to touch those programs which manipulate the internal representation of firewall rules). The code is almost entirely new (and I believe I have written the vast majority of those sections which were taken from the former ip_fw.c), so rather than modifying the old ip_fw.c I decided to create a new file, sys/netinet/ip_fw2.c . Same for the user interface, which is in sbin/ipfw/ipfw2.c (it still compiles to /sbin/ipfw). The old files are still there, and will be removed in due time. I have not renamed the header file because it would have required touching a one-line change to a number of kernel files. In terms of user interface, the new "ipfw" is supposed to accepts the old syntax for ipfw rules (and produce the same output with "ipfw show". Only a couple of the old options (out of some 30 of them) has not been implemented, but they will be soon. On the other hand, the new code has some very powerful extensions. First, you can put "or" connectives between match fields (and soon also between options), and write things like ipfw add allow ip from { 1.2.3.4/27 or 5.6.7.8/30 } 10-23,25,1024-3000 to any This should make rulesets slightly more compact (and lines longer!), by condensing 2 or more of the old rules into single ones. Also, as an example of how easy the rules can be extended, I have implemented an 'address set' match pattern, where you can specify an IP address in a format like this: 10.20.30.0/26{18,44,33,22,9} which will match the set of hosts listed in braces belonging to the subnet 10.20.30.0/26 . The match is done using a bitmap, so it is essentially a constant time operation requiring a handful of CPU instructions (and a very small amount of memmory -- for a full /24 subnet, the instruction only consumes 40 bytes). Again, in this commit I have focused on functionality and tried to minimize changes to the other parts of the system. Some performance improvement can be achieved with minor changes to the interface of ip_fw_chk_t. This will be done later when this code is settled. The code is meant to compile unmodified on RELENG_4 (once the PACKET_TAG_* changes have been merged), for this reason you will see #ifdef __FreeBSD_version in a couple of places. This should minimize errors when (hopefully soon) it will be time to do the MFC.
2002-06-27 23:02:18 +00:00
* Copyright (c) 2002 Luigi Rizzo, Universita` di Pisa
*
The new ipfw code. This code makes use of variable-size kernel representation of rules (exactly the same concept of BPF instructions, as used in the BSDI's firewall), which makes firewall operation a lot faster, and the code more readable and easier to extend and debug. The interface with the rest of the system is unchanged, as witnessed by this commit. The only extra kernel files that I am touching are if_fw.h and ip_dummynet.c, which is quite tied to ipfw. In userland I only had to touch those programs which manipulate the internal representation of firewall rules). The code is almost entirely new (and I believe I have written the vast majority of those sections which were taken from the former ip_fw.c), so rather than modifying the old ip_fw.c I decided to create a new file, sys/netinet/ip_fw2.c . Same for the user interface, which is in sbin/ipfw/ipfw2.c (it still compiles to /sbin/ipfw). The old files are still there, and will be removed in due time. I have not renamed the header file because it would have required touching a one-line change to a number of kernel files. In terms of user interface, the new "ipfw" is supposed to accepts the old syntax for ipfw rules (and produce the same output with "ipfw show". Only a couple of the old options (out of some 30 of them) has not been implemented, but they will be soon. On the other hand, the new code has some very powerful extensions. First, you can put "or" connectives between match fields (and soon also between options), and write things like ipfw add allow ip from { 1.2.3.4/27 or 5.6.7.8/30 } 10-23,25,1024-3000 to any This should make rulesets slightly more compact (and lines longer!), by condensing 2 or more of the old rules into single ones. Also, as an example of how easy the rules can be extended, I have implemented an 'address set' match pattern, where you can specify an IP address in a format like this: 10.20.30.0/26{18,44,33,22,9} which will match the set of hosts listed in braces belonging to the subnet 10.20.30.0/26 . The match is done using a bitmap, so it is essentially a constant time operation requiring a handful of CPU instructions (and a very small amount of memmory -- for a full /24 subnet, the instruction only consumes 40 bytes). Again, in this commit I have focused on functionality and tried to minimize changes to the other parts of the system. Some performance improvement can be achieved with minor changes to the interface of ip_fw_chk_t. This will be done later when this code is settled. The code is meant to compile unmodified on RELENG_4 (once the PACKET_TAG_* changes have been merged), for this reason you will see #ifdef __FreeBSD_version in a couple of places. This should minimize errors when (hopefully soon) it will be time to do the MFC.
2002-06-27 23:02:18 +00:00
* 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.
*
The new ipfw code. This code makes use of variable-size kernel representation of rules (exactly the same concept of BPF instructions, as used in the BSDI's firewall), which makes firewall operation a lot faster, and the code more readable and easier to extend and debug. The interface with the rest of the system is unchanged, as witnessed by this commit. The only extra kernel files that I am touching are if_fw.h and ip_dummynet.c, which is quite tied to ipfw. In userland I only had to touch those programs which manipulate the internal representation of firewall rules). The code is almost entirely new (and I believe I have written the vast majority of those sections which were taken from the former ip_fw.c), so rather than modifying the old ip_fw.c I decided to create a new file, sys/netinet/ip_fw2.c . Same for the user interface, which is in sbin/ipfw/ipfw2.c (it still compiles to /sbin/ipfw). The old files are still there, and will be removed in due time. I have not renamed the header file because it would have required touching a one-line change to a number of kernel files. In terms of user interface, the new "ipfw" is supposed to accepts the old syntax for ipfw rules (and produce the same output with "ipfw show". Only a couple of the old options (out of some 30 of them) has not been implemented, but they will be soon. On the other hand, the new code has some very powerful extensions. First, you can put "or" connectives between match fields (and soon also between options), and write things like ipfw add allow ip from { 1.2.3.4/27 or 5.6.7.8/30 } 10-23,25,1024-3000 to any This should make rulesets slightly more compact (and lines longer!), by condensing 2 or more of the old rules into single ones. Also, as an example of how easy the rules can be extended, I have implemented an 'address set' match pattern, where you can specify an IP address in a format like this: 10.20.30.0/26{18,44,33,22,9} which will match the set of hosts listed in braces belonging to the subnet 10.20.30.0/26 . The match is done using a bitmap, so it is essentially a constant time operation requiring a handful of CPU instructions (and a very small amount of memmory -- for a full /24 subnet, the instruction only consumes 40 bytes). Again, in this commit I have focused on functionality and tried to minimize changes to the other parts of the system. Some performance improvement can be achieved with minor changes to the interface of ip_fw_chk_t. This will be done later when this code is settled. The code is meant to compile unmodified on RELENG_4 (once the PACKET_TAG_* changes have been merged), for this reason you will see #ifdef __FreeBSD_version in a couple of places. This should minimize errors when (hopefully soon) it will be time to do the MFC.
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* 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.
1995-07-23 05:36:31 +00:00
*
1999-08-28 01:08:13 +00:00
* $FreeBSD$
*/
The new ipfw code. This code makes use of variable-size kernel representation of rules (exactly the same concept of BPF instructions, as used in the BSDI's firewall), which makes firewall operation a lot faster, and the code more readable and easier to extend and debug. The interface with the rest of the system is unchanged, as witnessed by this commit. The only extra kernel files that I am touching are if_fw.h and ip_dummynet.c, which is quite tied to ipfw. In userland I only had to touch those programs which manipulate the internal representation of firewall rules). The code is almost entirely new (and I believe I have written the vast majority of those sections which were taken from the former ip_fw.c), so rather than modifying the old ip_fw.c I decided to create a new file, sys/netinet/ip_fw2.c . Same for the user interface, which is in sbin/ipfw/ipfw2.c (it still compiles to /sbin/ipfw). The old files are still there, and will be removed in due time. I have not renamed the header file because it would have required touching a one-line change to a number of kernel files. In terms of user interface, the new "ipfw" is supposed to accepts the old syntax for ipfw rules (and produce the same output with "ipfw show". Only a couple of the old options (out of some 30 of them) has not been implemented, but they will be soon. On the other hand, the new code has some very powerful extensions. First, you can put "or" connectives between match fields (and soon also between options), and write things like ipfw add allow ip from { 1.2.3.4/27 or 5.6.7.8/30 } 10-23,25,1024-3000 to any This should make rulesets slightly more compact (and lines longer!), by condensing 2 or more of the old rules into single ones. Also, as an example of how easy the rules can be extended, I have implemented an 'address set' match pattern, where you can specify an IP address in a format like this: 10.20.30.0/26{18,44,33,22,9} which will match the set of hosts listed in braces belonging to the subnet 10.20.30.0/26 . The match is done using a bitmap, so it is essentially a constant time operation requiring a handful of CPU instructions (and a very small amount of memmory -- for a full /24 subnet, the instruction only consumes 40 bytes). Again, in this commit I have focused on functionality and tried to minimize changes to the other parts of the system. Some performance improvement can be achieved with minor changes to the interface of ip_fw_chk_t. This will be done later when this code is settled. The code is meant to compile unmodified on RELENG_4 (once the PACKET_TAG_* changes have been merged), for this reason you will see #ifdef __FreeBSD_version in a couple of places. This should minimize errors when (hopefully soon) it will be time to do the MFC.
2002-06-27 23:02:18 +00:00
#ifndef _IPFW2_H
#define _IPFW2_H
#define IPFW2 1
/*
The new ipfw code. This code makes use of variable-size kernel representation of rules (exactly the same concept of BPF instructions, as used in the BSDI's firewall), which makes firewall operation a lot faster, and the code more readable and easier to extend and debug. The interface with the rest of the system is unchanged, as witnessed by this commit. The only extra kernel files that I am touching are if_fw.h and ip_dummynet.c, which is quite tied to ipfw. In userland I only had to touch those programs which manipulate the internal representation of firewall rules). The code is almost entirely new (and I believe I have written the vast majority of those sections which were taken from the former ip_fw.c), so rather than modifying the old ip_fw.c I decided to create a new file, sys/netinet/ip_fw2.c . Same for the user interface, which is in sbin/ipfw/ipfw2.c (it still compiles to /sbin/ipfw). The old files are still there, and will be removed in due time. I have not renamed the header file because it would have required touching a one-line change to a number of kernel files. In terms of user interface, the new "ipfw" is supposed to accepts the old syntax for ipfw rules (and produce the same output with "ipfw show". Only a couple of the old options (out of some 30 of them) has not been implemented, but they will be soon. On the other hand, the new code has some very powerful extensions. First, you can put "or" connectives between match fields (and soon also between options), and write things like ipfw add allow ip from { 1.2.3.4/27 or 5.6.7.8/30 } 10-23,25,1024-3000 to any This should make rulesets slightly more compact (and lines longer!), by condensing 2 or more of the old rules into single ones. Also, as an example of how easy the rules can be extended, I have implemented an 'address set' match pattern, where you can specify an IP address in a format like this: 10.20.30.0/26{18,44,33,22,9} which will match the set of hosts listed in braces belonging to the subnet 10.20.30.0/26 . The match is done using a bitmap, so it is essentially a constant time operation requiring a handful of CPU instructions (and a very small amount of memmory -- for a full /24 subnet, the instruction only consumes 40 bytes). Again, in this commit I have focused on functionality and tried to minimize changes to the other parts of the system. Some performance improvement can be achieved with minor changes to the interface of ip_fw_chk_t. This will be done later when this code is settled. The code is meant to compile unmodified on RELENG_4 (once the PACKET_TAG_* changes have been merged), for this reason you will see #ifdef __FreeBSD_version in a couple of places. This should minimize errors when (hopefully soon) it will be time to do the MFC.
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* 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 new ipfw code. This code makes use of variable-size kernel representation of rules (exactly the same concept of BPF instructions, as used in the BSDI's firewall), which makes firewall operation a lot faster, and the code more readable and easier to extend and debug. The interface with the rest of the system is unchanged, as witnessed by this commit. The only extra kernel files that I am touching are if_fw.h and ip_dummynet.c, which is quite tied to ipfw. In userland I only had to touch those programs which manipulate the internal representation of firewall rules). The code is almost entirely new (and I believe I have written the vast majority of those sections which were taken from the former ip_fw.c), so rather than modifying the old ip_fw.c I decided to create a new file, sys/netinet/ip_fw2.c . Same for the user interface, which is in sbin/ipfw/ipfw2.c (it still compiles to /sbin/ipfw). The old files are still there, and will be removed in due time. I have not renamed the header file because it would have required touching a one-line change to a number of kernel files. In terms of user interface, the new "ipfw" is supposed to accepts the old syntax for ipfw rules (and produce the same output with "ipfw show". Only a couple of the old options (out of some 30 of them) has not been implemented, but they will be soon. On the other hand, the new code has some very powerful extensions. First, you can put "or" connectives between match fields (and soon also between options), and write things like ipfw add allow ip from { 1.2.3.4/27 or 5.6.7.8/30 } 10-23,25,1024-3000 to any This should make rulesets slightly more compact (and lines longer!), by condensing 2 or more of the old rules into single ones. Also, as an example of how easy the rules can be extended, I have implemented an 'address set' match pattern, where you can specify an IP address in a format like this: 10.20.30.0/26{18,44,33,22,9} which will match the set of hosts listed in braces belonging to the subnet 10.20.30.0/26 . The match is done using a bitmap, so it is essentially a constant time operation requiring a handful of CPU instructions (and a very small amount of memmory -- for a full /24 subnet, the instruction only consumes 40 bytes). Again, in this commit I have focused on functionality and tried to minimize changes to the other parts of the system. Some performance improvement can be achieved with minor changes to the interface of ip_fw_chk_t. This will be done later when this code is settled. The code is meant to compile unmodified on RELENG_4 (once the PACKET_TAG_* changes have been merged), for this reason you will see #ifdef __FreeBSD_version in a couple of places. This should minimize errors when (hopefully soon) it will be time to do the MFC.
2002-06-27 23:02:18 +00:00
* "enum ipfw_opcodes" are the opcodes supported. We can have up
* to 256 different opcodes.
*/
The new ipfw code. This code makes use of variable-size kernel representation of rules (exactly the same concept of BPF instructions, as used in the BSDI's firewall), which makes firewall operation a lot faster, and the code more readable and easier to extend and debug. The interface with the rest of the system is unchanged, as witnessed by this commit. The only extra kernel files that I am touching are if_fw.h and ip_dummynet.c, which is quite tied to ipfw. In userland I only had to touch those programs which manipulate the internal representation of firewall rules). The code is almost entirely new (and I believe I have written the vast majority of those sections which were taken from the former ip_fw.c), so rather than modifying the old ip_fw.c I decided to create a new file, sys/netinet/ip_fw2.c . Same for the user interface, which is in sbin/ipfw/ipfw2.c (it still compiles to /sbin/ipfw). The old files are still there, and will be removed in due time. I have not renamed the header file because it would have required touching a one-line change to a number of kernel files. In terms of user interface, the new "ipfw" is supposed to accepts the old syntax for ipfw rules (and produce the same output with "ipfw show". Only a couple of the old options (out of some 30 of them) has not been implemented, but they will be soon. On the other hand, the new code has some very powerful extensions. First, you can put "or" connectives between match fields (and soon also between options), and write things like ipfw add allow ip from { 1.2.3.4/27 or 5.6.7.8/30 } 10-23,25,1024-3000 to any This should make rulesets slightly more compact (and lines longer!), by condensing 2 or more of the old rules into single ones. Also, as an example of how easy the rules can be extended, I have implemented an 'address set' match pattern, where you can specify an IP address in a format like this: 10.20.30.0/26{18,44,33,22,9} which will match the set of hosts listed in braces belonging to the subnet 10.20.30.0/26 . The match is done using a bitmap, so it is essentially a constant time operation requiring a handful of CPU instructions (and a very small amount of memmory -- for a full /24 subnet, the instruction only consumes 40 bytes). Again, in this commit I have focused on functionality and tried to minimize changes to the other parts of the system. Some performance improvement can be achieved with minor changes to the interface of ip_fw_chk_t. This will be done later when this code is settled. The code is meant to compile unmodified on RELENG_4 (once the PACKET_TAG_* changes have been merged), for this reason you will see #ifdef __FreeBSD_version in a couple of places. This should minimize errors when (hopefully soon) it will be time to do the MFC.
2002-06-27 23:02:18 +00:00
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_IPTOS, /* arg1 = id */
O_IPPRECEDENCE, /* arg1 = precedence << 5 */
The new ipfw code. This code makes use of variable-size kernel representation of rules (exactly the same concept of BPF instructions, as used in the BSDI's firewall), which makes firewall operation a lot faster, and the code more readable and easier to extend and debug. The interface with the rest of the system is unchanged, as witnessed by this commit. The only extra kernel files that I am touching are if_fw.h and ip_dummynet.c, which is quite tied to ipfw. In userland I only had to touch those programs which manipulate the internal representation of firewall rules). The code is almost entirely new (and I believe I have written the vast majority of those sections which were taken from the former ip_fw.c), so rather than modifying the old ip_fw.c I decided to create a new file, sys/netinet/ip_fw2.c . Same for the user interface, which is in sbin/ipfw/ipfw2.c (it still compiles to /sbin/ipfw). The old files are still there, and will be removed in due time. I have not renamed the header file because it would have required touching a one-line change to a number of kernel files. In terms of user interface, the new "ipfw" is supposed to accepts the old syntax for ipfw rules (and produce the same output with "ipfw show". Only a couple of the old options (out of some 30 of them) has not been implemented, but they will be soon. On the other hand, the new code has some very powerful extensions. First, you can put "or" connectives between match fields (and soon also between options), and write things like ipfw add allow ip from { 1.2.3.4/27 or 5.6.7.8/30 } 10-23,25,1024-3000 to any This should make rulesets slightly more compact (and lines longer!), by condensing 2 or more of the old rules into single ones. Also, as an example of how easy the rules can be extended, I have implemented an 'address set' match pattern, where you can specify an IP address in a format like this: 10.20.30.0/26{18,44,33,22,9} which will match the set of hosts listed in braces belonging to the subnet 10.20.30.0/26 . The match is done using a bitmap, so it is essentially a constant time operation requiring a handful of CPU instructions (and a very small amount of memmory -- for a full /24 subnet, the instruction only consumes 40 bytes). Again, in this commit I have focused on functionality and tried to minimize changes to the other parts of the system. Some performance improvement can be achieved with minor changes to the interface of ip_fw_chk_t. This will be done later when this code is settled. The code is meant to compile unmodified on RELENG_4 (once the PACKET_TAG_* changes have been merged), for this reason you will see #ifdef __FreeBSD_version in a couple of places. This should minimize errors when (hopefully soon) it will be time to do the MFC.
2002-06-27 23:02:18 +00:00
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! */
};
/*
The new ipfw code. This code makes use of variable-size kernel representation of rules (exactly the same concept of BPF instructions, as used in the BSDI's firewall), which makes firewall operation a lot faster, and the code more readable and easier to extend and debug. The interface with the rest of the system is unchanged, as witnessed by this commit. The only extra kernel files that I am touching are if_fw.h and ip_dummynet.c, which is quite tied to ipfw. In userland I only had to touch those programs which manipulate the internal representation of firewall rules). The code is almost entirely new (and I believe I have written the vast majority of those sections which were taken from the former ip_fw.c), so rather than modifying the old ip_fw.c I decided to create a new file, sys/netinet/ip_fw2.c . Same for the user interface, which is in sbin/ipfw/ipfw2.c (it still compiles to /sbin/ipfw). The old files are still there, and will be removed in due time. I have not renamed the header file because it would have required touching a one-line change to a number of kernel files. In terms of user interface, the new "ipfw" is supposed to accepts the old syntax for ipfw rules (and produce the same output with "ipfw show". Only a couple of the old options (out of some 30 of them) has not been implemented, but they will be soon. On the other hand, the new code has some very powerful extensions. First, you can put "or" connectives between match fields (and soon also between options), and write things like ipfw add allow ip from { 1.2.3.4/27 or 5.6.7.8/30 } 10-23,25,1024-3000 to any This should make rulesets slightly more compact (and lines longer!), by condensing 2 or more of the old rules into single ones. Also, as an example of how easy the rules can be extended, I have implemented an 'address set' match pattern, where you can specify an IP address in a format like this: 10.20.30.0/26{18,44,33,22,9} which will match the set of hosts listed in braces belonging to the subnet 10.20.30.0/26 . The match is done using a bitmap, so it is essentially a constant time operation requiring a handful of CPU instructions (and a very small amount of memmory -- for a full /24 subnet, the instruction only consumes 40 bytes). Again, in this commit I have focused on functionality and tried to minimize changes to the other parts of the system. Some performance improvement can be achieved with minor changes to the interface of ip_fw_chk_t. This will be done later when this code is settled. The code is meant to compile unmodified on RELENG_4 (once the PACKET_TAG_* changes have been merged), for this reason you will see #ifdef __FreeBSD_version in a couple of places. This should minimize errors when (hopefully soon) it will be time to do the MFC.
2002-06-27 23:02:18 +00:00
* 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.
*
*/
The new ipfw code. This code makes use of variable-size kernel representation of rules (exactly the same concept of BPF instructions, as used in the BSDI's firewall), which makes firewall operation a lot faster, and the code more readable and easier to extend and debug. The interface with the rest of the system is unchanged, as witnessed by this commit. The only extra kernel files that I am touching are if_fw.h and ip_dummynet.c, which is quite tied to ipfw. In userland I only had to touch those programs which manipulate the internal representation of firewall rules). The code is almost entirely new (and I believe I have written the vast majority of those sections which were taken from the former ip_fw.c), so rather than modifying the old ip_fw.c I decided to create a new file, sys/netinet/ip_fw2.c . Same for the user interface, which is in sbin/ipfw/ipfw2.c (it still compiles to /sbin/ipfw). The old files are still there, and will be removed in due time. I have not renamed the header file because it would have required touching a one-line change to a number of kernel files. In terms of user interface, the new "ipfw" is supposed to accepts the old syntax for ipfw rules (and produce the same output with "ipfw show". Only a couple of the old options (out of some 30 of them) has not been implemented, but they will be soon. On the other hand, the new code has some very powerful extensions. First, you can put "or" connectives between match fields (and soon also between options), and write things like ipfw add allow ip from { 1.2.3.4/27 or 5.6.7.8/30 } 10-23,25,1024-3000 to any This should make rulesets slightly more compact (and lines longer!), by condensing 2 or more of the old rules into single ones. Also, as an example of how easy the rules can be extended, I have implemented an 'address set' match pattern, where you can specify an IP address in a format like this: 10.20.30.0/26{18,44,33,22,9} which will match the set of hosts listed in braces belonging to the subnet 10.20.30.0/26 . The match is done using a bitmap, so it is essentially a constant time operation requiring a handful of CPU instructions (and a very small amount of memmory -- for a full /24 subnet, the instruction only consumes 40 bytes). Again, in this commit I have focused on functionality and tried to minimize changes to the other parts of the system. Some performance improvement can be achieved with minor changes to the interface of ip_fw_chk_t. This will be done later when this code is settled. The code is meant to compile unmodified on RELENG_4 (once the PACKET_TAG_* changes have been merged), for this reason you will see #ifdef __FreeBSD_version in a couple of places. This should minimize errors when (hopefully soon) it will be time to do the MFC.
2002-06-27 23:02:18 +00:00
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;
/*
The new ipfw code. This code makes use of variable-size kernel representation of rules (exactly the same concept of BPF instructions, as used in the BSDI's firewall), which makes firewall operation a lot faster, and the code more readable and easier to extend and debug. The interface with the rest of the system is unchanged, as witnessed by this commit. The only extra kernel files that I am touching are if_fw.h and ip_dummynet.c, which is quite tied to ipfw. In userland I only had to touch those programs which manipulate the internal representation of firewall rules). The code is almost entirely new (and I believe I have written the vast majority of those sections which were taken from the former ip_fw.c), so rather than modifying the old ip_fw.c I decided to create a new file, sys/netinet/ip_fw2.c . Same for the user interface, which is in sbin/ipfw/ipfw2.c (it still compiles to /sbin/ipfw). The old files are still there, and will be removed in due time. I have not renamed the header file because it would have required touching a one-line change to a number of kernel files. In terms of user interface, the new "ipfw" is supposed to accepts the old syntax for ipfw rules (and produce the same output with "ipfw show". Only a couple of the old options (out of some 30 of them) has not been implemented, but they will be soon. On the other hand, the new code has some very powerful extensions. First, you can put "or" connectives between match fields (and soon also between options), and write things like ipfw add allow ip from { 1.2.3.4/27 or 5.6.7.8/30 } 10-23,25,1024-3000 to any This should make rulesets slightly more compact (and lines longer!), by condensing 2 or more of the old rules into single ones. Also, as an example of how easy the rules can be extended, I have implemented an 'address set' match pattern, where you can specify an IP address in a format like this: 10.20.30.0/26{18,44,33,22,9} which will match the set of hosts listed in braces belonging to the subnet 10.20.30.0/26 . The match is done using a bitmap, so it is essentially a constant time operation requiring a handful of CPU instructions (and a very small amount of memmory -- for a full /24 subnet, the instruction only consumes 40 bytes). Again, in this commit I have focused on functionality and tried to minimize changes to the other parts of the system. Some performance improvement can be achieved with minor changes to the interface of ip_fw_chk_t. This will be done later when this code is settled. The code is meant to compile unmodified on RELENG_4 (once the PACKET_TAG_* changes have been merged), for this reason you will see #ifdef __FreeBSD_version in a couple of places. This should minimize errors when (hopefully soon) it will be time to do the MFC.
2002-06-27 23:02:18 +00:00
* The F_INSN_SIZE(type) computes the size, in 4-byte words, of
* a given type.
*/
The new ipfw code. This code makes use of variable-size kernel representation of rules (exactly the same concept of BPF instructions, as used in the BSDI's firewall), which makes firewall operation a lot faster, and the code more readable and easier to extend and debug. The interface with the rest of the system is unchanged, as witnessed by this commit. The only extra kernel files that I am touching are if_fw.h and ip_dummynet.c, which is quite tied to ipfw. In userland I only had to touch those programs which manipulate the internal representation of firewall rules). The code is almost entirely new (and I believe I have written the vast majority of those sections which were taken from the former ip_fw.c), so rather than modifying the old ip_fw.c I decided to create a new file, sys/netinet/ip_fw2.c . Same for the user interface, which is in sbin/ipfw/ipfw2.c (it still compiles to /sbin/ipfw). The old files are still there, and will be removed in due time. I have not renamed the header file because it would have required touching a one-line change to a number of kernel files. In terms of user interface, the new "ipfw" is supposed to accepts the old syntax for ipfw rules (and produce the same output with "ipfw show". Only a couple of the old options (out of some 30 of them) has not been implemented, but they will be soon. On the other hand, the new code has some very powerful extensions. First, you can put "or" connectives between match fields (and soon also between options), and write things like ipfw add allow ip from { 1.2.3.4/27 or 5.6.7.8/30 } 10-23,25,1024-3000 to any This should make rulesets slightly more compact (and lines longer!), by condensing 2 or more of the old rules into single ones. Also, as an example of how easy the rules can be extended, I have implemented an 'address set' match pattern, where you can specify an IP address in a format like this: 10.20.30.0/26{18,44,33,22,9} which will match the set of hosts listed in braces belonging to the subnet 10.20.30.0/26 . The match is done using a bitmap, so it is essentially a constant time operation requiring a handful of CPU instructions (and a very small amount of memmory -- for a full /24 subnet, the instruction only consumes 40 bytes). Again, in this commit I have focused on functionality and tried to minimize changes to the other parts of the system. Some performance improvement can be achieved with minor changes to the interface of ip_fw_chk_t. This will be done later when this code is settled. The code is meant to compile unmodified on RELENG_4 (once the PACKET_TAG_* changes have been merged), for this reason you will see #ifdef __FreeBSD_version in a couple of places. This should minimize errors when (hopefully soon) it will be time to do the MFC.
2002-06-27 23:02:18 +00:00
#define F_INSN_SIZE(t) ((sizeof (t))/sizeof(u_int32_t))
The new ipfw code. This code makes use of variable-size kernel representation of rules (exactly the same concept of BPF instructions, as used in the BSDI's firewall), which makes firewall operation a lot faster, and the code more readable and easier to extend and debug. The interface with the rest of the system is unchanged, as witnessed by this commit. The only extra kernel files that I am touching are if_fw.h and ip_dummynet.c, which is quite tied to ipfw. In userland I only had to touch those programs which manipulate the internal representation of firewall rules). The code is almost entirely new (and I believe I have written the vast majority of those sections which were taken from the former ip_fw.c), so rather than modifying the old ip_fw.c I decided to create a new file, sys/netinet/ip_fw2.c . Same for the user interface, which is in sbin/ipfw/ipfw2.c (it still compiles to /sbin/ipfw). The old files are still there, and will be removed in due time. I have not renamed the header file because it would have required touching a one-line change to a number of kernel files. In terms of user interface, the new "ipfw" is supposed to accepts the old syntax for ipfw rules (and produce the same output with "ipfw show". Only a couple of the old options (out of some 30 of them) has not been implemented, but they will be soon. On the other hand, the new code has some very powerful extensions. First, you can put "or" connectives between match fields (and soon also between options), and write things like ipfw add allow ip from { 1.2.3.4/27 or 5.6.7.8/30 } 10-23,25,1024-3000 to any This should make rulesets slightly more compact (and lines longer!), by condensing 2 or more of the old rules into single ones. Also, as an example of how easy the rules can be extended, I have implemented an 'address set' match pattern, where you can specify an IP address in a format like this: 10.20.30.0/26{18,44,33,22,9} which will match the set of hosts listed in braces belonging to the subnet 10.20.30.0/26 . The match is done using a bitmap, so it is essentially a constant time operation requiring a handful of CPU instructions (and a very small amount of memmory -- for a full /24 subnet, the instruction only consumes 40 bytes). Again, in this commit I have focused on functionality and tried to minimize changes to the other parts of the system. Some performance improvement can be achieved with minor changes to the interface of ip_fw_chk_t. This will be done later when this code is settled. The code is meant to compile unmodified on RELENG_4 (once the PACKET_TAG_* changes have been merged), for this reason you will see #ifdef __FreeBSD_version in a couple of places. This should minimize errors when (hopefully soon) it will be time to do the MFC.
2002-06-27 23:02:18 +00:00
/*
* 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
The new ipfw code. This code makes use of variable-size kernel representation of rules (exactly the same concept of BPF instructions, as used in the BSDI's firewall), which makes firewall operation a lot faster, and the code more readable and easier to extend and debug. The interface with the rest of the system is unchanged, as witnessed by this commit. The only extra kernel files that I am touching are if_fw.h and ip_dummynet.c, which is quite tied to ipfw. In userland I only had to touch those programs which manipulate the internal representation of firewall rules). The code is almost entirely new (and I believe I have written the vast majority of those sections which were taken from the former ip_fw.c), so rather than modifying the old ip_fw.c I decided to create a new file, sys/netinet/ip_fw2.c . Same for the user interface, which is in sbin/ipfw/ipfw2.c (it still compiles to /sbin/ipfw). The old files are still there, and will be removed in due time. I have not renamed the header file because it would have required touching a one-line change to a number of kernel files. In terms of user interface, the new "ipfw" is supposed to accepts the old syntax for ipfw rules (and produce the same output with "ipfw show". Only a couple of the old options (out of some 30 of them) has not been implemented, but they will be soon. On the other hand, the new code has some very powerful extensions. First, you can put "or" connectives between match fields (and soon also between options), and write things like ipfw add allow ip from { 1.2.3.4/27 or 5.6.7.8/30 } 10-23,25,1024-3000 to any This should make rulesets slightly more compact (and lines longer!), by condensing 2 or more of the old rules into single ones. Also, as an example of how easy the rules can be extended, I have implemented an 'address set' match pattern, where you can specify an IP address in a format like this: 10.20.30.0/26{18,44,33,22,9} which will match the set of hosts listed in braces belonging to the subnet 10.20.30.0/26 . The match is done using a bitmap, so it is essentially a constant time operation requiring a handful of CPU instructions (and a very small amount of memmory -- for a full /24 subnet, the instruction only consumes 40 bytes). Again, in this commit I have focused on functionality and tried to minimize changes to the other parts of the system. Some performance improvement can be achieved with minor changes to the interface of ip_fw_chk_t. This will be done later when this code is settled. The code is meant to compile unmodified on RELENG_4 (once the PACKET_TAG_* changes have been merged), for this reason you will see #ifdef __FreeBSD_version in a couple of places. This should minimize errors when (hopefully soon) it will be time to do the MFC.
2002-06-27 23:02:18 +00:00
u_int16_t conn_limit;
} ipfw_insn_limit;
The new ipfw code. This code makes use of variable-size kernel representation of rules (exactly the same concept of BPF instructions, as used in the BSDI's firewall), which makes firewall operation a lot faster, and the code more readable and easier to extend and debug. The interface with the rest of the system is unchanged, as witnessed by this commit. The only extra kernel files that I am touching are if_fw.h and ip_dummynet.c, which is quite tied to ipfw. In userland I only had to touch those programs which manipulate the internal representation of firewall rules). The code is almost entirely new (and I believe I have written the vast majority of those sections which were taken from the former ip_fw.c), so rather than modifying the old ip_fw.c I decided to create a new file, sys/netinet/ip_fw2.c . Same for the user interface, which is in sbin/ipfw/ipfw2.c (it still compiles to /sbin/ipfw). The old files are still there, and will be removed in due time. I have not renamed the header file because it would have required touching a one-line change to a number of kernel files. In terms of user interface, the new "ipfw" is supposed to accepts the old syntax for ipfw rules (and produce the same output with "ipfw show". Only a couple of the old options (out of some 30 of them) has not been implemented, but they will be soon. On the other hand, the new code has some very powerful extensions. First, you can put "or" connectives between match fields (and soon also between options), and write things like ipfw add allow ip from { 1.2.3.4/27 or 5.6.7.8/30 } 10-23,25,1024-3000 to any This should make rulesets slightly more compact (and lines longer!), by condensing 2 or more of the old rules into single ones. Also, as an example of how easy the rules can be extended, I have implemented an 'address set' match pattern, where you can specify an IP address in a format like this: 10.20.30.0/26{18,44,33,22,9} which will match the set of hosts listed in braces belonging to the subnet 10.20.30.0/26 . The match is done using a bitmap, so it is essentially a constant time operation requiring a handful of CPU instructions (and a very small amount of memmory -- for a full /24 subnet, the instruction only consumes 40 bytes). Again, in this commit I have focused on functionality and tried to minimize changes to the other parts of the system. Some performance improvement can be achieved with minor changes to the interface of ip_fw_chk_t. This will be done later when this code is settled. The code is meant to compile unmodified on RELENG_4 (once the PACKET_TAG_* changes have been merged), for this reason you will see #ifdef __FreeBSD_version in a couple of places. This should minimize errors when (hopefully soon) it will be time to do the MFC.
2002-06-27 23:02:18 +00:00
/*
* 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;
/*
The new ipfw code. This code makes use of variable-size kernel representation of rules (exactly the same concept of BPF instructions, as used in the BSDI's firewall), which makes firewall operation a lot faster, and the code more readable and easier to extend and debug. The interface with the rest of the system is unchanged, as witnessed by this commit. The only extra kernel files that I am touching are if_fw.h and ip_dummynet.c, which is quite tied to ipfw. In userland I only had to touch those programs which manipulate the internal representation of firewall rules). The code is almost entirely new (and I believe I have written the vast majority of those sections which were taken from the former ip_fw.c), so rather than modifying the old ip_fw.c I decided to create a new file, sys/netinet/ip_fw2.c . Same for the user interface, which is in sbin/ipfw/ipfw2.c (it still compiles to /sbin/ipfw). The old files are still there, and will be removed in due time. I have not renamed the header file because it would have required touching a one-line change to a number of kernel files. In terms of user interface, the new "ipfw" is supposed to accepts the old syntax for ipfw rules (and produce the same output with "ipfw show". Only a couple of the old options (out of some 30 of them) has not been implemented, but they will be soon. On the other hand, the new code has some very powerful extensions. First, you can put "or" connectives between match fields (and soon also between options), and write things like ipfw add allow ip from { 1.2.3.4/27 or 5.6.7.8/30 } 10-23,25,1024-3000 to any This should make rulesets slightly more compact (and lines longer!), by condensing 2 or more of the old rules into single ones. Also, as an example of how easy the rules can be extended, I have implemented an 'address set' match pattern, where you can specify an IP address in a format like this: 10.20.30.0/26{18,44,33,22,9} which will match the set of hosts listed in braces belonging to the subnet 10.20.30.0/26 . The match is done using a bitmap, so it is essentially a constant time operation requiring a handful of CPU instructions (and a very small amount of memmory -- for a full /24 subnet, the instruction only consumes 40 bytes). Again, in this commit I have focused on functionality and tried to minimize changes to the other parts of the system. Some performance improvement can be achieved with minor changes to the interface of ip_fw_chk_t. This will be done later when this code is settled. The code is meant to compile unmodified on RELENG_4 (once the PACKET_TAG_* changes have been merged), for this reason you will see #ifdef __FreeBSD_version in a couple of places. This should minimize errors when (hopefully soon) it will be time to do the MFC.
2002-06-27 23:02:18 +00:00
* 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:
*
The new ipfw code. This code makes use of variable-size kernel representation of rules (exactly the same concept of BPF instructions, as used in the BSDI's firewall), which makes firewall operation a lot faster, and the code more readable and easier to extend and debug. The interface with the rest of the system is unchanged, as witnessed by this commit. The only extra kernel files that I am touching are if_fw.h and ip_dummynet.c, which is quite tied to ipfw. In userland I only had to touch those programs which manipulate the internal representation of firewall rules). The code is almost entirely new (and I believe I have written the vast majority of those sections which were taken from the former ip_fw.c), so rather than modifying the old ip_fw.c I decided to create a new file, sys/netinet/ip_fw2.c . Same for the user interface, which is in sbin/ipfw/ipfw2.c (it still compiles to /sbin/ipfw). The old files are still there, and will be removed in due time. I have not renamed the header file because it would have required touching a one-line change to a number of kernel files. In terms of user interface, the new "ipfw" is supposed to accepts the old syntax for ipfw rules (and produce the same output with "ipfw show". Only a couple of the old options (out of some 30 of them) has not been implemented, but they will be soon. On the other hand, the new code has some very powerful extensions. First, you can put "or" connectives between match fields (and soon also between options), and write things like ipfw add allow ip from { 1.2.3.4/27 or 5.6.7.8/30 } 10-23,25,1024-3000 to any This should make rulesets slightly more compact (and lines longer!), by condensing 2 or more of the old rules into single ones. Also, as an example of how easy the rules can be extended, I have implemented an 'address set' match pattern, where you can specify an IP address in a format like this: 10.20.30.0/26{18,44,33,22,9} which will match the set of hosts listed in braces belonging to the subnet 10.20.30.0/26 . The match is done using a bitmap, so it is essentially a constant time operation requiring a handful of CPU instructions (and a very small amount of memmory -- for a full /24 subnet, the instruction only consumes 40 bytes). Again, in this commit I have focused on functionality and tried to minimize changes to the other parts of the system. Some performance improvement can be achieved with minor changes to the interface of ip_fw_chk_t. This will be done later when this code is settled. The code is meant to compile unmodified on RELENG_4 (once the PACKET_TAG_* changes have been merged), for this reason you will see #ifdef __FreeBSD_version in a couple of places. This should minimize errors when (hopefully soon) it will be time to do the MFC.
2002-06-27 23:02:18 +00:00
* + 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
*
The new ipfw code. This code makes use of variable-size kernel representation of rules (exactly the same concept of BPF instructions, as used in the BSDI's firewall), which makes firewall operation a lot faster, and the code more readable and easier to extend and debug. The interface with the rest of the system is unchanged, as witnessed by this commit. The only extra kernel files that I am touching are if_fw.h and ip_dummynet.c, which is quite tied to ipfw. In userland I only had to touch those programs which manipulate the internal representation of firewall rules). The code is almost entirely new (and I believe I have written the vast majority of those sections which were taken from the former ip_fw.c), so rather than modifying the old ip_fw.c I decided to create a new file, sys/netinet/ip_fw2.c . Same for the user interface, which is in sbin/ipfw/ipfw2.c (it still compiles to /sbin/ipfw). The old files are still there, and will be removed in due time. I have not renamed the header file because it would have required touching a one-line change to a number of kernel files. In terms of user interface, the new "ipfw" is supposed to accepts the old syntax for ipfw rules (and produce the same output with "ipfw show". Only a couple of the old options (out of some 30 of them) has not been implemented, but they will be soon. On the other hand, the new code has some very powerful extensions. First, you can put "or" connectives between match fields (and soon also between options), and write things like ipfw add allow ip from { 1.2.3.4/27 or 5.6.7.8/30 } 10-23,25,1024-3000 to any This should make rulesets slightly more compact (and lines longer!), by condensing 2 or more of the old rules into single ones. Also, as an example of how easy the rules can be extended, I have implemented an 'address set' match pattern, where you can specify an IP address in a format like this: 10.20.30.0/26{18,44,33,22,9} which will match the set of hosts listed in braces belonging to the subnet 10.20.30.0/26 . The match is done using a bitmap, so it is essentially a constant time operation requiring a handful of CPU instructions (and a very small amount of memmory -- for a full /24 subnet, the instruction only consumes 40 bytes). Again, in this commit I have focused on functionality and tried to minimize changes to the other parts of the system. Some performance improvement can be achieved with minor changes to the interface of ip_fw_chk_t. This will be done later when this code is settled. The code is meant to compile unmodified on RELENG_4 (once the PACKET_TAG_* changes have been merged), for this reason you will see #ifdef __FreeBSD_version in a couple of places. This should minimize errors when (hopefully soon) it will be time to do the MFC.
2002-06-27 23:02:18 +00:00
* 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.
*/
The new ipfw code. This code makes use of variable-size kernel representation of rules (exactly the same concept of BPF instructions, as used in the BSDI's firewall), which makes firewall operation a lot faster, and the code more readable and easier to extend and debug. The interface with the rest of the system is unchanged, as witnessed by this commit. The only extra kernel files that I am touching are if_fw.h and ip_dummynet.c, which is quite tied to ipfw. In userland I only had to touch those programs which manipulate the internal representation of firewall rules). The code is almost entirely new (and I believe I have written the vast majority of those sections which were taken from the former ip_fw.c), so rather than modifying the old ip_fw.c I decided to create a new file, sys/netinet/ip_fw2.c . Same for the user interface, which is in sbin/ipfw/ipfw2.c (it still compiles to /sbin/ipfw). The old files are still there, and will be removed in due time. I have not renamed the header file because it would have required touching a one-line change to a number of kernel files. In terms of user interface, the new "ipfw" is supposed to accepts the old syntax for ipfw rules (and produce the same output with "ipfw show". Only a couple of the old options (out of some 30 of them) has not been implemented, but they will be soon. On the other hand, the new code has some very powerful extensions. First, you can put "or" connectives between match fields (and soon also between options), and write things like ipfw add allow ip from { 1.2.3.4/27 or 5.6.7.8/30 } 10-23,25,1024-3000 to any This should make rulesets slightly more compact (and lines longer!), by condensing 2 or more of the old rules into single ones. Also, as an example of how easy the rules can be extended, I have implemented an 'address set' match pattern, where you can specify an IP address in a format like this: 10.20.30.0/26{18,44,33,22,9} which will match the set of hosts listed in braces belonging to the subnet 10.20.30.0/26 . The match is done using a bitmap, so it is essentially a constant time operation requiring a handful of CPU instructions (and a very small amount of memmory -- for a full /24 subnet, the instruction only consumes 40 bytes). Again, in this commit I have focused on functionality and tried to minimize changes to the other parts of the system. Some performance improvement can be achieved with minor changes to the interface of ip_fw_chk_t. This will be done later when this code is settled. The code is meant to compile unmodified on RELENG_4 (once the PACKET_TAG_* changes have been merged), for this reason you will see #ifdef __FreeBSD_version in a couple of places. This should minimize errors when (hopefully soon) it will be time to do the MFC.
2002-06-27 23:02:18 +00:00
struct ip_fw {
struct ip_fw *next; /* linked list of rules */
struct ip_fw *next_rule; /* ptr to next [skipto] rule */
The new ipfw code. This code makes use of variable-size kernel representation of rules (exactly the same concept of BPF instructions, as used in the BSDI's firewall), which makes firewall operation a lot faster, and the code more readable and easier to extend and debug. The interface with the rest of the system is unchanged, as witnessed by this commit. The only extra kernel files that I am touching are if_fw.h and ip_dummynet.c, which is quite tied to ipfw. In userland I only had to touch those programs which manipulate the internal representation of firewall rules). The code is almost entirely new (and I believe I have written the vast majority of those sections which were taken from the former ip_fw.c), so rather than modifying the old ip_fw.c I decided to create a new file, sys/netinet/ip_fw2.c . Same for the user interface, which is in sbin/ipfw/ipfw2.c (it still compiles to /sbin/ipfw). The old files are still there, and will be removed in due time. I have not renamed the header file because it would have required touching a one-line change to a number of kernel files. In terms of user interface, the new "ipfw" is supposed to accepts the old syntax for ipfw rules (and produce the same output with "ipfw show". Only a couple of the old options (out of some 30 of them) has not been implemented, but they will be soon. On the other hand, the new code has some very powerful extensions. First, you can put "or" connectives between match fields (and soon also between options), and write things like ipfw add allow ip from { 1.2.3.4/27 or 5.6.7.8/30 } 10-23,25,1024-3000 to any This should make rulesets slightly more compact (and lines longer!), by condensing 2 or more of the old rules into single ones. Also, as an example of how easy the rules can be extended, I have implemented an 'address set' match pattern, where you can specify an IP address in a format like this: 10.20.30.0/26{18,44,33,22,9} which will match the set of hosts listed in braces belonging to the subnet 10.20.30.0/26 . The match is done using a bitmap, so it is essentially a constant time operation requiring a handful of CPU instructions (and a very small amount of memmory -- for a full /24 subnet, the instruction only consumes 40 bytes). Again, in this commit I have focused on functionality and tried to minimize changes to the other parts of the system. Some performance improvement can be achieved with minor changes to the interface of ip_fw_chk_t. This will be done later when this code is settled. The code is meant to compile unmodified on RELENG_4 (once the PACKET_TAG_* changes have been merged), for this reason you will see #ifdef __FreeBSD_version in a couple of places. This should minimize errors when (hopefully soon) it will be time to do the MFC.
2002-06-27 23:02:18 +00:00
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 */
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)
/*
The new ipfw code. This code makes use of variable-size kernel representation of rules (exactly the same concept of BPF instructions, as used in the BSDI's firewall), which makes firewall operation a lot faster, and the code more readable and easier to extend and debug. The interface with the rest of the system is unchanged, as witnessed by this commit. The only extra kernel files that I am touching are if_fw.h and ip_dummynet.c, which is quite tied to ipfw. In userland I only had to touch those programs which manipulate the internal representation of firewall rules). The code is almost entirely new (and I believe I have written the vast majority of those sections which were taken from the former ip_fw.c), so rather than modifying the old ip_fw.c I decided to create a new file, sys/netinet/ip_fw2.c . Same for the user interface, which is in sbin/ipfw/ipfw2.c (it still compiles to /sbin/ipfw). The old files are still there, and will be removed in due time. I have not renamed the header file because it would have required touching a one-line change to a number of kernel files. In terms of user interface, the new "ipfw" is supposed to accepts the old syntax for ipfw rules (and produce the same output with "ipfw show". Only a couple of the old options (out of some 30 of them) has not been implemented, but they will be soon. On the other hand, the new code has some very powerful extensions. First, you can put "or" connectives between match fields (and soon also between options), and write things like ipfw add allow ip from { 1.2.3.4/27 or 5.6.7.8/30 } 10-23,25,1024-3000 to any This should make rulesets slightly more compact (and lines longer!), by condensing 2 or more of the old rules into single ones. Also, as an example of how easy the rules can be extended, I have implemented an 'address set' match pattern, where you can specify an IP address in a format like this: 10.20.30.0/26{18,44,33,22,9} which will match the set of hosts listed in braces belonging to the subnet 10.20.30.0/26 . The match is done using a bitmap, so it is essentially a constant time operation requiring a handful of CPU instructions (and a very small amount of memmory -- for a full /24 subnet, the instruction only consumes 40 bytes). Again, in this commit I have focused on functionality and tried to minimize changes to the other parts of the system. Some performance improvement can be achieved with minor changes to the interface of ip_fw_chk_t. This will be done later when this code is settled. The code is meant to compile unmodified on RELENG_4 (once the PACKET_TAG_* changes have been merged), for this reason you will see #ifdef __FreeBSD_version in a couple of places. This should minimize errors when (hopefully soon) it will be time to do the MFC.
2002-06-27 23:02:18 +00:00
* 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;
u_int32_t src_ip;
u_int16_t dst_port;
u_int16_t src_port;
u_int8_t proto;
u_int8_t flags; /* protocol-specific flags */
};
/*
* dynamic ipfw rule
*/
The new ipfw code. This code makes use of variable-size kernel representation of rules (exactly the same concept of BPF instructions, as used in the BSDI's firewall), which makes firewall operation a lot faster, and the code more readable and easier to extend and debug. The interface with the rest of the system is unchanged, as witnessed by this commit. The only extra kernel files that I am touching are if_fw.h and ip_dummynet.c, which is quite tied to ipfw. In userland I only had to touch those programs which manipulate the internal representation of firewall rules). The code is almost entirely new (and I believe I have written the vast majority of those sections which were taken from the former ip_fw.c), so rather than modifying the old ip_fw.c I decided to create a new file, sys/netinet/ip_fw2.c . Same for the user interface, which is in sbin/ipfw/ipfw2.c (it still compiles to /sbin/ipfw). The old files are still there, and will be removed in due time. I have not renamed the header file because it would have required touching a one-line change to a number of kernel files. In terms of user interface, the new "ipfw" is supposed to accepts the old syntax for ipfw rules (and produce the same output with "ipfw show". Only a couple of the old options (out of some 30 of them) has not been implemented, but they will be soon. On the other hand, the new code has some very powerful extensions. First, you can put "or" connectives between match fields (and soon also between options), and write things like ipfw add allow ip from { 1.2.3.4/27 or 5.6.7.8/30 } 10-23,25,1024-3000 to any This should make rulesets slightly more compact (and lines longer!), by condensing 2 or more of the old rules into single ones. Also, as an example of how easy the rules can be extended, I have implemented an 'address set' match pattern, where you can specify an IP address in a format like this: 10.20.30.0/26{18,44,33,22,9} which will match the set of hosts listed in braces belonging to the subnet 10.20.30.0/26 . The match is done using a bitmap, so it is essentially a constant time operation requiring a handful of CPU instructions (and a very small amount of memmory -- for a full /24 subnet, the instruction only consumes 40 bytes). Again, in this commit I have focused on functionality and tried to minimize changes to the other parts of the system. Some performance improvement can be achieved with minor changes to the interface of ip_fw_chk_t. This will be done later when this code is settled. The code is meant to compile unmodified on RELENG_4 (once the PACKET_TAG_* changes have been merged), for this reason you will see #ifdef __FreeBSD_version in a couple of places. This should minimize errors when (hopefully soon) it will be time to do the MFC.
2002-06-27 23:02:18 +00:00
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_int32_t ack_fwd; /* most recent ACKs in forward */
u_int32_t ack_rev; /* and reverse directions (used */
/* to generate keepalives) */
The new ipfw code. This code makes use of variable-size kernel representation of rules (exactly the same concept of BPF instructions, as used in the BSDI's firewall), which makes firewall operation a lot faster, and the code more readable and easier to extend and debug. The interface with the rest of the system is unchanged, as witnessed by this commit. The only extra kernel files that I am touching are if_fw.h and ip_dummynet.c, which is quite tied to ipfw. In userland I only had to touch those programs which manipulate the internal representation of firewall rules). The code is almost entirely new (and I believe I have written the vast majority of those sections which were taken from the former ip_fw.c), so rather than modifying the old ip_fw.c I decided to create a new file, sys/netinet/ip_fw2.c . Same for the user interface, which is in sbin/ipfw/ipfw2.c (it still compiles to /sbin/ipfw). The old files are still there, and will be removed in due time. I have not renamed the header file because it would have required touching a one-line change to a number of kernel files. In terms of user interface, the new "ipfw" is supposed to accepts the old syntax for ipfw rules (and produce the same output with "ipfw show". Only a couple of the old options (out of some 30 of them) has not been implemented, but they will be soon. On the other hand, the new code has some very powerful extensions. First, you can put "or" connectives between match fields (and soon also between options), and write things like ipfw add allow ip from { 1.2.3.4/27 or 5.6.7.8/30 } 10-23,25,1024-3000 to any This should make rulesets slightly more compact (and lines longer!), by condensing 2 or more of the old rules into single ones. Also, as an example of how easy the rules can be extended, I have implemented an 'address set' match pattern, where you can specify an IP address in a format like this: 10.20.30.0/26{18,44,33,22,9} which will match the set of hosts listed in braces belonging to the subnet 10.20.30.0/26 . The match is done using a bitmap, so it is essentially a constant time operation requiring a handful of CPU instructions (and a very small amount of memmory -- for a full /24 subnet, the instruction only consumes 40 bytes). Again, in this commit I have focused on functionality and tried to minimize changes to the other parts of the system. Some performance improvement can be achieved with minor changes to the interface of ip_fw_chk_t. This will be done later when this code is settled. The code is meant to compile unmodified on RELENG_4 (once the PACKET_TAG_* changes have been merged), for this reason you will see #ifdef __FreeBSD_version in a couple of places. This should minimize errors when (hopefully soon) it will be time to do the MFC.
2002-06-27 23:02:18 +00:00
u_int16_t dyn_type; /* rule type */
u_int16_t count; /* refcount */
};
/*
* Definitions for IP option names.
*/
#define IP_FW_IPOPT_LSRR 0x01
#define IP_FW_IPOPT_SSRR 0x02
#define IP_FW_IPOPT_RR 0x04
#define IP_FW_IPOPT_TS 0x08
/*
* Definitions for TCP option names.
*/
#define IP_FW_TCPOPT_MSS 0x01
#define IP_FW_TCPOPT_WINDOW 0x02
#define IP_FW_TCPOPT_SACK 0x04
#define IP_FW_TCPOPT_TS 0x08
#define IP_FW_TCPOPT_CC 0x10
The new ipfw code. This code makes use of variable-size kernel representation of rules (exactly the same concept of BPF instructions, as used in the BSDI's firewall), which makes firewall operation a lot faster, and the code more readable and easier to extend and debug. The interface with the rest of the system is unchanged, as witnessed by this commit. The only extra kernel files that I am touching are if_fw.h and ip_dummynet.c, which is quite tied to ipfw. In userland I only had to touch those programs which manipulate the internal representation of firewall rules). The code is almost entirely new (and I believe I have written the vast majority of those sections which were taken from the former ip_fw.c), so rather than modifying the old ip_fw.c I decided to create a new file, sys/netinet/ip_fw2.c . Same for the user interface, which is in sbin/ipfw/ipfw2.c (it still compiles to /sbin/ipfw). The old files are still there, and will be removed in due time. I have not renamed the header file because it would have required touching a one-line change to a number of kernel files. In terms of user interface, the new "ipfw" is supposed to accepts the old syntax for ipfw rules (and produce the same output with "ipfw show". Only a couple of the old options (out of some 30 of them) has not been implemented, but they will be soon. On the other hand, the new code has some very powerful extensions. First, you can put "or" connectives between match fields (and soon also between options), and write things like ipfw add allow ip from { 1.2.3.4/27 or 5.6.7.8/30 } 10-23,25,1024-3000 to any This should make rulesets slightly more compact (and lines longer!), by condensing 2 or more of the old rules into single ones. Also, as an example of how easy the rules can be extended, I have implemented an 'address set' match pattern, where you can specify an IP address in a format like this: 10.20.30.0/26{18,44,33,22,9} which will match the set of hosts listed in braces belonging to the subnet 10.20.30.0/26 . The match is done using a bitmap, so it is essentially a constant time operation requiring a handful of CPU instructions (and a very small amount of memmory -- for a full /24 subnet, the instruction only consumes 40 bytes). Again, in this commit I have focused on functionality and tried to minimize changes to the other parts of the system. Some performance improvement can be achieved with minor changes to the interface of ip_fw_chk_t. This will be done later when this code is settled. The code is meant to compile unmodified on RELENG_4 (once the PACKET_TAG_* changes have been merged), for this reason you will see #ifdef __FreeBSD_version in a couple of places. This should minimize errors when (hopefully soon) it will be time to do the MFC.
2002-06-27 23:02:18 +00:00
#define ICMP_REJECT_RST 0x100 /* fake ICMP code (send a TCP RST) */
/*
* Main firewall chains definitions and global var's definitions.
*/
#ifdef _KERNEL
#define IP_FW_PORT_DYNT_FLAG 0x10000
#define IP_FW_PORT_TEE_FLAG 0x20000
#define IP_FW_PORT_DENY_FLAG 0x40000
Remove (almost all) global variables that were used to hold packet forwarding state ("annotations") during ip processing. The code is considerably cleaner now. The variables removed by this change are: ip_divert_cookie used by divert sockets ip_fw_fwd_addr used for transparent ip redirection last_pkt used by dynamic pipes in dummynet Removal of the first two has been done by carrying the annotations into volatile structs prepended to the mbuf chains, and adding appropriate code to add/remove annotations in the routines which make use of them, i.e. ip_input(), ip_output(), tcp_input(), bdg_forward(), ether_demux(), ether_output_frame(), div_output(). On passing, remove a bug in divert handling of fragmented packet. Now it is the fragment at offset 0 which sets the divert status of the whole packet, whereas formerly it was the last incoming fragment to decide. Removal of last_pkt required a change in the interface of ip_fw_chk() and dummynet_io(). On passing, use the same mechanism for dummynet annotations and for divert/forward annotations. option IPFIREWALL_FORWARD is effectively useless, the code to implement it is very small and is now in by default to avoid the obfuscation of conditionally compiled code. NOTES: * there is at least one global variable left, sro_fwd, in ip_output(). I am not sure if/how this can be removed. * I have deliberately avoided gratuitous style changes in this commit to avoid cluttering the diffs. Minor stule cleanup will likely be necessary * this commit only focused on the IP layer. I am sure there is a number of global variables used in the TCP and maybe UDP stack. * despite the number of files touched, there are absolutely no API's or data structures changed by this commit (except the interfaces of ip_fw_chk() and dummynet_io(), which are internal anyways), so an MFC is quite safe and unintrusive (and desirable, given the improved readability of the code). MFC after: 10 days
2002-06-22 11:51:02 +00:00
/*
The new ipfw code. This code makes use of variable-size kernel representation of rules (exactly the same concept of BPF instructions, as used in the BSDI's firewall), which makes firewall operation a lot faster, and the code more readable and easier to extend and debug. The interface with the rest of the system is unchanged, as witnessed by this commit. The only extra kernel files that I am touching are if_fw.h and ip_dummynet.c, which is quite tied to ipfw. In userland I only had to touch those programs which manipulate the internal representation of firewall rules). The code is almost entirely new (and I believe I have written the vast majority of those sections which were taken from the former ip_fw.c), so rather than modifying the old ip_fw.c I decided to create a new file, sys/netinet/ip_fw2.c . Same for the user interface, which is in sbin/ipfw/ipfw2.c (it still compiles to /sbin/ipfw). The old files are still there, and will be removed in due time. I have not renamed the header file because it would have required touching a one-line change to a number of kernel files. In terms of user interface, the new "ipfw" is supposed to accepts the old syntax for ipfw rules (and produce the same output with "ipfw show". Only a couple of the old options (out of some 30 of them) has not been implemented, but they will be soon. On the other hand, the new code has some very powerful extensions. First, you can put "or" connectives between match fields (and soon also between options), and write things like ipfw add allow ip from { 1.2.3.4/27 or 5.6.7.8/30 } 10-23,25,1024-3000 to any This should make rulesets slightly more compact (and lines longer!), by condensing 2 or more of the old rules into single ones. Also, as an example of how easy the rules can be extended, I have implemented an 'address set' match pattern, where you can specify an IP address in a format like this: 10.20.30.0/26{18,44,33,22,9} which will match the set of hosts listed in braces belonging to the subnet 10.20.30.0/26 . The match is done using a bitmap, so it is essentially a constant time operation requiring a handful of CPU instructions (and a very small amount of memmory -- for a full /24 subnet, the instruction only consumes 40 bytes). Again, in this commit I have focused on functionality and tried to minimize changes to the other parts of the system. Some performance improvement can be achieved with minor changes to the interface of ip_fw_chk_t. This will be done later when this code is settled. The code is meant to compile unmodified on RELENG_4 (once the PACKET_TAG_* changes have been merged), for this reason you will see #ifdef __FreeBSD_version in a couple of places. This should minimize errors when (hopefully soon) it will be time to do the MFC.
2002-06-27 23:02:18 +00:00
* arguments for calling ipfw_chk() and dummynet_io(). We put them
Remove (almost all) global variables that were used to hold packet forwarding state ("annotations") during ip processing. The code is considerably cleaner now. The variables removed by this change are: ip_divert_cookie used by divert sockets ip_fw_fwd_addr used for transparent ip redirection last_pkt used by dynamic pipes in dummynet Removal of the first two has been done by carrying the annotations into volatile structs prepended to the mbuf chains, and adding appropriate code to add/remove annotations in the routines which make use of them, i.e. ip_input(), ip_output(), tcp_input(), bdg_forward(), ether_demux(), ether_output_frame(), div_output(). On passing, remove a bug in divert handling of fragmented packet. Now it is the fragment at offset 0 which sets the divert status of the whole packet, whereas formerly it was the last incoming fragment to decide. Removal of last_pkt required a change in the interface of ip_fw_chk() and dummynet_io(). On passing, use the same mechanism for dummynet annotations and for divert/forward annotations. option IPFIREWALL_FORWARD is effectively useless, the code to implement it is very small and is now in by default to avoid the obfuscation of conditionally compiled code. NOTES: * there is at least one global variable left, sro_fwd, in ip_output(). I am not sure if/how this can be removed. * I have deliberately avoided gratuitous style changes in this commit to avoid cluttering the diffs. Minor stule cleanup will likely be necessary * this commit only focused on the IP layer. I am sure there is a number of global variables used in the TCP and maybe UDP stack. * despite the number of files touched, there are absolutely no API's or data structures changed by this commit (except the interfaces of ip_fw_chk() and dummynet_io(), which are internal anyways), so an MFC is quite safe and unintrusive (and desirable, given the improved readability of the code). MFC after: 10 days
2002-06-22 11:51:02 +00:00
* all into a structure because this way it is easier and more
* efficient to pass variables around and extend the interface.
*/
struct ip_fw_args {
struct mbuf *m; /* the mbuf chain */
struct ifnet *oif; /* output interface */
struct sockaddr_in *next_hop; /* forward address */
struct ip_fw *rule; /* matching rule */
struct ether_header *eh; /* for bridged packets */
struct route *ro; /* for dummynet */
struct sockaddr_in *dst; /* for dummynet */
int flags; /* for dummynet */
struct ipfw_flow_id f_id; /* grabbed from IP header */
u_int16_t divert_rule; /* divert cookie */
u_int32_t retval;
};
/*
* Function definitions.
*/
/* Firewall hooks */
struct sockopt;
The new ipfw code. This code makes use of variable-size kernel representation of rules (exactly the same concept of BPF instructions, as used in the BSDI's firewall), which makes firewall operation a lot faster, and the code more readable and easier to extend and debug. The interface with the rest of the system is unchanged, as witnessed by this commit. The only extra kernel files that I am touching are if_fw.h and ip_dummynet.c, which is quite tied to ipfw. In userland I only had to touch those programs which manipulate the internal representation of firewall rules). The code is almost entirely new (and I believe I have written the vast majority of those sections which were taken from the former ip_fw.c), so rather than modifying the old ip_fw.c I decided to create a new file, sys/netinet/ip_fw2.c . Same for the user interface, which is in sbin/ipfw/ipfw2.c (it still compiles to /sbin/ipfw). The old files are still there, and will be removed in due time. I have not renamed the header file because it would have required touching a one-line change to a number of kernel files. In terms of user interface, the new "ipfw" is supposed to accepts the old syntax for ipfw rules (and produce the same output with "ipfw show". Only a couple of the old options (out of some 30 of them) has not been implemented, but they will be soon. On the other hand, the new code has some very powerful extensions. First, you can put "or" connectives between match fields (and soon also between options), and write things like ipfw add allow ip from { 1.2.3.4/27 or 5.6.7.8/30 } 10-23,25,1024-3000 to any This should make rulesets slightly more compact (and lines longer!), by condensing 2 or more of the old rules into single ones. Also, as an example of how easy the rules can be extended, I have implemented an 'address set' match pattern, where you can specify an IP address in a format like this: 10.20.30.0/26{18,44,33,22,9} which will match the set of hosts listed in braces belonging to the subnet 10.20.30.0/26 . The match is done using a bitmap, so it is essentially a constant time operation requiring a handful of CPU instructions (and a very small amount of memmory -- for a full /24 subnet, the instruction only consumes 40 bytes). Again, in this commit I have focused on functionality and tried to minimize changes to the other parts of the system. Some performance improvement can be achieved with minor changes to the interface of ip_fw_chk_t. This will be done later when this code is settled. The code is meant to compile unmodified on RELENG_4 (once the PACKET_TAG_* changes have been merged), for this reason you will see #ifdef __FreeBSD_version in a couple of places. This should minimize errors when (hopefully soon) it will be time to do the MFC.
2002-06-27 23:02:18 +00:00
struct dn_flow_set;
void flush_pipe_ptrs(struct dn_flow_set *match); /* used by dummynet */
Remove (almost all) global variables that were used to hold packet forwarding state ("annotations") during ip processing. The code is considerably cleaner now. The variables removed by this change are: ip_divert_cookie used by divert sockets ip_fw_fwd_addr used for transparent ip redirection last_pkt used by dynamic pipes in dummynet Removal of the first two has been done by carrying the annotations into volatile structs prepended to the mbuf chains, and adding appropriate code to add/remove annotations in the routines which make use of them, i.e. ip_input(), ip_output(), tcp_input(), bdg_forward(), ether_demux(), ether_output_frame(), div_output(). On passing, remove a bug in divert handling of fragmented packet. Now it is the fragment at offset 0 which sets the divert status of the whole packet, whereas formerly it was the last incoming fragment to decide. Removal of last_pkt required a change in the interface of ip_fw_chk() and dummynet_io(). On passing, use the same mechanism for dummynet annotations and for divert/forward annotations. option IPFIREWALL_FORWARD is effectively useless, the code to implement it is very small and is now in by default to avoid the obfuscation of conditionally compiled code. NOTES: * there is at least one global variable left, sro_fwd, in ip_output(). I am not sure if/how this can be removed. * I have deliberately avoided gratuitous style changes in this commit to avoid cluttering the diffs. Minor stule cleanup will likely be necessary * this commit only focused on the IP layer. I am sure there is a number of global variables used in the TCP and maybe UDP stack. * despite the number of files touched, there are absolutely no API's or data structures changed by this commit (except the interfaces of ip_fw_chk() and dummynet_io(), which are internal anyways), so an MFC is quite safe and unintrusive (and desirable, given the improved readability of the code). MFC after: 10 days
2002-06-22 11:51:02 +00:00
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;
extern ip_fw_ctl_t *ip_fw_ctl_ptr;
extern int fw_one_pass;
extern int fw_enable;
#define IPFW_LOADED (ip_fw_chk_ptr != NULL)
#endif /* _KERNEL */
The new ipfw code. This code makes use of variable-size kernel representation of rules (exactly the same concept of BPF instructions, as used in the BSDI's firewall), which makes firewall operation a lot faster, and the code more readable and easier to extend and debug. The interface with the rest of the system is unchanged, as witnessed by this commit. The only extra kernel files that I am touching are if_fw.h and ip_dummynet.c, which is quite tied to ipfw. In userland I only had to touch those programs which manipulate the internal representation of firewall rules). The code is almost entirely new (and I believe I have written the vast majority of those sections which were taken from the former ip_fw.c), so rather than modifying the old ip_fw.c I decided to create a new file, sys/netinet/ip_fw2.c . Same for the user interface, which is in sbin/ipfw/ipfw2.c (it still compiles to /sbin/ipfw). The old files are still there, and will be removed in due time. I have not renamed the header file because it would have required touching a one-line change to a number of kernel files. In terms of user interface, the new "ipfw" is supposed to accepts the old syntax for ipfw rules (and produce the same output with "ipfw show". Only a couple of the old options (out of some 30 of them) has not been implemented, but they will be soon. On the other hand, the new code has some very powerful extensions. First, you can put "or" connectives between match fields (and soon also between options), and write things like ipfw add allow ip from { 1.2.3.4/27 or 5.6.7.8/30 } 10-23,25,1024-3000 to any This should make rulesets slightly more compact (and lines longer!), by condensing 2 or more of the old rules into single ones. Also, as an example of how easy the rules can be extended, I have implemented an 'address set' match pattern, where you can specify an IP address in a format like this: 10.20.30.0/26{18,44,33,22,9} which will match the set of hosts listed in braces belonging to the subnet 10.20.30.0/26 . The match is done using a bitmap, so it is essentially a constant time operation requiring a handful of CPU instructions (and a very small amount of memmory -- for a full /24 subnet, the instruction only consumes 40 bytes). Again, in this commit I have focused on functionality and tried to minimize changes to the other parts of the system. Some performance improvement can be achieved with minor changes to the interface of ip_fw_chk_t. This will be done later when this code is settled. The code is meant to compile unmodified on RELENG_4 (once the PACKET_TAG_* changes have been merged), for this reason you will see #ifdef __FreeBSD_version in a couple of places. This should minimize errors when (hopefully soon) it will be time to do the MFC.
2002-06-27 23:02:18 +00:00
#endif /* _IPFW2_H */