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Diffstat (limited to 'freebsd/sys/netinet/ip_fw.h')
| -rw-r--r-- | freebsd/sys/netinet/ip_fw.h | 579 |
1 files changed, 579 insertions, 0 deletions
diff --git a/freebsd/sys/netinet/ip_fw.h b/freebsd/sys/netinet/ip_fw.h new file mode 100644 index 00000000..cf5d8d03 --- /dev/null +++ b/freebsd/sys/netinet/ip_fw.h @@ -0,0 +1,579 @@ +/*- + * Copyright (c) 2002-2009 Luigi Rizzo, Universita` di Pisa + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * $FreeBSD$ + */ + +#ifndef _IPFW2_H +#define _IPFW2_H + +/* + * The default rule number. By the design of ip_fw, the default rule + * is the last one, so its number can also serve as the highest number + * allowed for a rule. The ip_fw code relies on both meanings of this + * constant. + */ +#define IPFW_DEFAULT_RULE 65535 + +/* + * The number of ipfw tables. The maximum allowed table number is the + * (IPFW_TABLES_MAX - 1). + */ +#define IPFW_TABLES_MAX 128 + +/* + * Most commands (queue, pipe, tag, untag, limit...) can have a 16-bit + * argument between 1 and 65534. The value 0 is unused, the value + * 65535 (IP_FW_TABLEARG) is used to represent 'tablearg', i.e. the + * can be 1..65534, or 65535 to indicate the use of a 'tablearg' + * result of the most recent table() lookup. + * Note that 16bit is only a historical limit, resulting from + * the use of a 16-bit fields for that value. In reality, we can have + * 2^32 pipes, queues, tag values and so on, and use 0 as a tablearg. + */ +#define IPFW_ARG_MIN 1 +#define IPFW_ARG_MAX 65534 +#define IP_FW_TABLEARG 65535 /* XXX should use 0 */ + +/* + * 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 metadata) 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). + * Note that the code is written so that individual instructions + * have a size which is a multiple of 32 bits. This means that, if + * such structures contain pointers or other 64-bit entities, + * (there is just one instance now) they may end up unaligned on + * 64-bit architectures, so the must be handled with care. + * + * "enum ipfw_opcodes" are the opcodes supported. We can have up + * to 256 different opcodes. When adding new opcodes, they should + * be appended to the end of the opcode list before O_LAST_OPCODE, + * this will prevent the ABI from being broken, otherwise users + * will have to recompile ipfw(8) when they update the kernel. + */ + +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 */ + 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_VERREVPATH, /* none */ + O_VERSRCREACH, /* none */ + + 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'. + */ + + 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_NAT, /* nope */ + O_REASS, /* none */ + + /* + * More opcodes. + */ + O_IPSEC, /* has ipsec history */ + O_IP_SRC_LOOKUP, /* arg1=table number, u32=value */ + O_IP_DST_LOOKUP, /* arg1=table number, u32=value */ + O_ANTISPOOF, /* none */ + O_JAIL, /* u32 = id */ + O_ALTQ, /* u32 = altq classif. qid */ + O_DIVERTED, /* arg1=bitmap (1:loop, 2:out) */ + O_TCPDATALEN, /* arg1 = tcp data len */ + O_IP6_SRC, /* address without mask */ + O_IP6_SRC_ME, /* my addresses */ + O_IP6_SRC_MASK, /* address with the mask */ + O_IP6_DST, + O_IP6_DST_ME, + O_IP6_DST_MASK, + O_FLOW6ID, /* for flow id tag in the ipv6 pkt */ + O_ICMP6TYPE, /* icmp6 packet type filtering */ + O_EXT_HDR, /* filtering for ipv6 extension header */ + O_IP6, + + /* + * actions for ng_ipfw + */ + O_NETGRAPH, /* send to ng_ipfw */ + O_NGTEE, /* copy to ng_ipfw */ + + O_IP4, + + O_UNREACH6, /* arg1=icmpv6 code arg (deny) */ + + O_TAG, /* arg1=tag number */ + O_TAGGED, /* arg1=tag number */ + + O_SETFIB, /* arg1=FIB number */ + O_FIB, /* arg1=FIB desired fib number */ + + O_LAST_OPCODE /* not an opcode! */ +}; + +/* + * The extension header are filtered only for presence using a bit + * vector with a flag for each header. + */ +#define EXT_FRAGMENT 0x1 +#define EXT_HOPOPTS 0x2 +#define EXT_ROUTING 0x4 +#define EXT_AH 0x8 +#define EXT_ESP 0x10 +#define EXT_DSTOPTS 0x20 +#define EXT_RTHDR0 0x40 +#define EXT_RTHDR2 0x80 + +/* + * 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. + * + */ +typedef struct _ipfw_insn { /* template for instructions */ + u_int8_t opcode; + u_int8_t len; /* number of 32-bit 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 F_INSN_SIZE(type) computes the size, in 4-byte words, of + * a given type. + */ +#define F_INSN_SIZE(t) ((sizeof (t))/sizeof(u_int32_t)) + +/* + * 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 glob; + } p; + char name[IFNAMSIZ]; +} ipfw_insn_if; + +/* + * This is used for storing an altq queue id number. + */ +typedef struct _ipfw_insn_altq { + ipfw_insn o; + u_int32_t qid; +} ipfw_insn_altq; + +/* + * This is used for limit rules. + */ +typedef struct _ipfw_insn_limit { + ipfw_insn o; + u_int8_t _pad; + u_int8_t limit_mask; /* combination of DYN_* below */ +#define DYN_SRC_ADDR 0x1 +#define DYN_SRC_PORT 0x2 +#define DYN_DST_ADDR 0x4 +#define DYN_DST_PORT 0x8 + + u_int16_t conn_limit; +} ipfw_insn_limit; + +/* + * 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; + +/* + * Data structures required by both ipfw(8) and ipfw(4) but not part of the + * management API are protected by IPFW_INTERNAL. + */ +#ifdef IPFW_INTERNAL +/* Server pool support (LSNAT). */ +struct cfg_spool { + LIST_ENTRY(cfg_spool) _next; /* chain of spool instances */ + struct in_addr addr; + u_short port; +}; +#endif + +/* Redirect modes id. */ +#define REDIR_ADDR 0x01 +#define REDIR_PORT 0x02 +#define REDIR_PROTO 0x04 + +#ifdef IPFW_INTERNAL +/* Nat redirect configuration. */ +struct cfg_redir { + LIST_ENTRY(cfg_redir) _next; /* chain of redir instances */ + u_int16_t mode; /* type of redirect mode */ + struct in_addr laddr; /* local ip address */ + struct in_addr paddr; /* public ip address */ + struct in_addr raddr; /* remote ip address */ + u_short lport; /* local port */ + u_short pport; /* public port */ + u_short rport; /* remote port */ + u_short pport_cnt; /* number of public ports */ + u_short rport_cnt; /* number of remote ports */ + int proto; /* protocol: tcp/udp */ + struct alias_link **alink; + /* num of entry in spool chain */ + u_int16_t spool_cnt; + /* chain of spool instances */ + LIST_HEAD(spool_chain, cfg_spool) spool_chain; +}; +#endif + +#define NAT_BUF_LEN 1024 + +#ifdef IPFW_INTERNAL +/* Nat configuration data struct. */ +struct cfg_nat { + /* chain of nat instances */ + LIST_ENTRY(cfg_nat) _next; + int id; /* nat id */ + struct in_addr ip; /* nat ip address */ + char if_name[IF_NAMESIZE]; /* interface name */ + int mode; /* aliasing mode */ + struct libalias *lib; /* libalias instance */ + /* number of entry in spool chain */ + int redir_cnt; + /* chain of redir instances */ + LIST_HEAD(redir_chain, cfg_redir) redir_chain; +}; +#endif + +#define SOF_NAT sizeof(struct cfg_nat) +#define SOF_REDIR sizeof(struct cfg_redir) +#define SOF_SPOOL sizeof(struct cfg_spool) + +/* Nat command. */ +typedef struct _ipfw_insn_nat { + ipfw_insn o; + struct cfg_nat *nat; +} ipfw_insn_nat; + +/* Apply ipv6 mask on ipv6 addr */ +#define APPLY_MASK(addr,mask) \ + (addr)->__u6_addr.__u6_addr32[0] &= (mask)->__u6_addr.__u6_addr32[0]; \ + (addr)->__u6_addr.__u6_addr32[1] &= (mask)->__u6_addr.__u6_addr32[1]; \ + (addr)->__u6_addr.__u6_addr32[2] &= (mask)->__u6_addr.__u6_addr32[2]; \ + (addr)->__u6_addr.__u6_addr32[3] &= (mask)->__u6_addr.__u6_addr32[3]; + +/* Structure for ipv6 */ +typedef struct _ipfw_insn_ip6 { + ipfw_insn o; + struct in6_addr addr6; + struct in6_addr mask6; +} ipfw_insn_ip6; + +/* Used to support icmp6 types */ +typedef struct _ipfw_insn_icmp6 { + ipfw_insn o; + uint32_t d[7]; /* XXX This number si related to the netinet/icmp6.h + * define ICMP6_MAXTYPE + * as follows: n = ICMP6_MAXTYPE/32 + 1 + * Actually is 203 + */ +} ipfw_insn_icmp6; + +/* + * 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: + * + * + 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 + * + if a rule has an "altq" option, it comes after "log" + * + if a rule has an O_TAG option, it comes after "log" and "altq" + * + * NOTE: we use a simple linked list of rules because we never need + * to delete a rule without scanning the list. We do not use + * queue(3) macros for portability and readability. + */ + +struct ip_fw { + struct ip_fw *x_next; /* linked list of rules */ + struct ip_fw *next_rule; /* ptr to next [skipto] rule */ + /* 'next_rule' is used to pass up 'set_disable' status */ + + uint16_t act_ofs; /* offset of action in 32-bit units */ + uint16_t cmd_len; /* # of 32-bit words in cmd */ + uint16_t rulenum; /* rule number */ + uint8_t set; /* rule set (0..31) */ +#define RESVD_SET 31 /* set for default and persistent rules */ + uint8_t _pad; /* padding */ + uint32_t id; /* rule id */ + + /* These fields are present in all rules. */ + uint64_t pcnt; /* Packet counter */ + uint64_t bcnt; /* Byte counter */ + uint32_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) + +#if 1 // should be moved to in.h +/* + * This structure is used as a flow mask and a flow id for various + * parts of the code. + * addr_type is used in userland and kernel to mark the address type. + * fib is used in the kernel to record the fib in use. + * _flags is used in the kernel to store tcp flags for dynamic rules. + */ +struct ipfw_flow_id { + uint32_t dst_ip; + uint32_t src_ip; + uint16_t dst_port; + uint16_t src_port; + uint8_t fib; + uint8_t proto; + uint8_t _flags; /* protocol-specific flags */ + uint8_t addr_type; /* 4=ip4, 6=ip6, 1=ether ? */ + struct in6_addr dst_ip6; + struct in6_addr src_ip6; + uint32_t flow_id6; + uint32_t extra; /* queue/pipe or frag_id */ +}; +#endif + +#define IS_IP6_FLOW_ID(id) ((id)->addr_type == 6) + +/* + * Dynamic ipfw rule. + */ +typedef struct _ipfw_dyn_rule ipfw_dyn_rule; + +struct _ipfw_dyn_rule { + ipfw_dyn_rule *next; /* linked list of rules. */ + struct ip_fw *rule; /* pointer to rule */ + /* 'rule' is used to pass up the rule number (from the parent) */ + + ipfw_dyn_rule *parent; /* pointer to parent rule */ + u_int64_t pcnt; /* packet match counter */ + u_int64_t bcnt; /* byte match counter */ + struct ipfw_flow_id id; /* (masked) flow id */ + u_int32_t expire; /* expire time */ + 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) */ + 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 + +#define ICMP_REJECT_RST 0x100 /* fake ICMP code (send a TCP RST) */ +#define ICMP6_UNREACH_RST 0x100 /* fake ICMPv6 code (send a TCP RST) */ + +/* + * These are used for lookup tables. + */ +typedef struct _ipfw_table_entry { + in_addr_t addr; /* network address */ + u_int32_t value; /* value */ + u_int16_t tbl; /* table number */ + u_int8_t masklen; /* mask length */ +} ipfw_table_entry; + +typedef struct _ipfw_table { + u_int32_t size; /* size of entries in bytes */ + u_int32_t cnt; /* # of entries */ + u_int16_t tbl; /* table number */ + ipfw_table_entry ent[0]; /* entries */ +} ipfw_table; + +#endif /* _IPFW2_H */ |