/* * 25-Jul-1998 Major changes to allow for ip chain table * * 3-Jan-2000 Named tables to allow packet selection for different uses. */ /* * Format of an IP6 firewall descriptor * * src, dst, src_mask, dst_mask are always stored in network byte order. * flags are stored in host byte order (of course). * Port numbers are stored in HOST byte order. */ #ifndef _IP6_TABLES_H #define _IP6_TABLES_H #ifdef __KERNEL__ #include #include #include #include #include #endif #include #include #define IP6T_FUNCTION_MAXNAMELEN 30 #define IP6T_TABLE_MAXNAMELEN 32 /* Yes, Virginia, you have to zero the padding. */ struct ip6t_ip6 { /* Source and destination IP6 addr */ struct in6_addr src, dst; /* Mask for src and dest IP6 addr */ struct in6_addr smsk, dmsk; char iniface[IFNAMSIZ], outiface[IFNAMSIZ]; unsigned char iniface_mask[IFNAMSIZ], outiface_mask[IFNAMSIZ]; /* ARGH, HopByHop uses 0, so can't do 0 = ANY, instead IP6T_F_NOPROTO must be set */ u_int16_t proto; /* TOS to match iff flags & IP6T_F_TOS */ u_int8_t tos; /* Flags word */ u_int8_t flags; /* Inverse flags */ u_int8_t invflags; }; /* FIXME: If alignment in kernel different from userspace? --RR */ struct ip6t_entry_match { union { struct { u_int16_t match_size; /* Used by userspace */ char name[IP6T_FUNCTION_MAXNAMELEN-1]; u_int8_t revision; } user; struct { u_int16_t match_size; /* Used inside the kernel */ struct ip6t_match *match; } kernel; /* Total length */ u_int16_t match_size; } u; unsigned char data[0]; }; struct ip6t_entry_target { union { struct { u_int16_t target_size; /* Used by userspace */ char name[IP6T_FUNCTION_MAXNAMELEN-1]; u_int8_t revision; } user; struct { u_int16_t target_size; /* Used inside the kernel */ struct ip6t_target *target; } kernel; /* Total length */ u_int16_t target_size; } u; unsigned char data[0]; }; struct ip6t_standard_target { struct ip6t_entry_target target; int verdict; }; struct ip6t_counters { u_int64_t pcnt, bcnt; /* Packet and byte counters */ }; /* Values for "flag" field in struct ip6t_ip6 (general ip6 structure). */ #define IP6T_F_PROTO 0x01 /* Set if rule cares about upper protocols */ #define IP6T_F_TOS 0x02 /* Match the TOS. */ #define IP6T_F_GOTO 0x04 /* Set if jump is a goto */ #define IP6T_F_MASK 0x07 /* All possible flag bits mask. */ /* Values for "inv" field in struct ip6t_ip6. */ #define IP6T_INV_VIA_IN 0x01 /* Invert the sense of IN IFACE. */ #define IP6T_INV_VIA_OUT 0x02 /* Invert the sense of OUT IFACE */ #define IP6T_INV_TOS 0x04 /* Invert the sense of TOS. */ #define IP6T_INV_SRCIP 0x08 /* Invert the sense of SRC IP. */ #define IP6T_INV_DSTIP 0x10 /* Invert the sense of DST OP. */ #define IP6T_INV_FRAG 0x20 /* Invert the sense of FRAG. */ #define IP6T_INV_PROTO 0x40 /* Invert the sense of PROTO. */ #define IP6T_INV_MASK 0x7F /* All possible flag bits mask. */ /* This structure defines each of the firewall rules. Consists of 3 parts which are 1) general IP header stuff 2) match specific stuff 3) the target to perform if the rule matches */ struct ip6t_entry { struct ip6t_ip6 ipv6; /* Mark with fields that we care about. */ unsigned int nfcache; /* Size of ipt_entry + matches */ u_int16_t target_offset; /* Size of ipt_entry + matches + target */ u_int16_t next_offset; /* Back pointer */ unsigned int comefrom; /* Packet and byte counters. */ struct ip6t_counters counters; /* The matches (if any), then the target. */ unsigned char elems[0]; }; /* * New IP firewall options for [gs]etsockopt at the RAW IP level. * Unlike BSD Linux inherits IP options so you don't have to use * a raw socket for this. Instead we check rights in the calls. */ #define IP6T_BASE_CTL 64 /* base for firewall socket options */ #define IP6T_SO_SET_REPLACE (IP6T_BASE_CTL) #define IP6T_SO_SET_ADD_COUNTERS (IP6T_BASE_CTL + 1) #define IP6T_SO_SET_MAX IP6T_SO_SET_ADD_COUNTERS #define IP6T_SO_GET_INFO (IP6T_BASE_CTL) #define IP6T_SO_GET_ENTRIES (IP6T_BASE_CTL + 1) #define IP6T_SO_GET_REVISION_MATCH (IP6T_BASE_CTL + 2) #define IP6T_SO_GET_REVISION_TARGET (IP6T_BASE_CTL + 3) #define IP6T_SO_GET_MAX IP6T_SO_GET_REVISION_TARGET /* CONTINUE verdict for targets */ #define IP6T_CONTINUE 0xFFFFFFFF /* For standard target */ #define IP6T_RETURN (-NF_REPEAT - 1) /* TCP matching stuff */ struct ip6t_tcp { u_int16_t spts[2]; /* Source port range. */ u_int16_t dpts[2]; /* Destination port range. */ u_int8_t option; /* TCP Option iff non-zero*/ u_int8_t flg_mask; /* TCP flags mask byte */ u_int8_t flg_cmp; /* TCP flags compare byte */ u_int8_t invflags; /* Inverse flags */ }; /* Values for "inv" field in struct ipt_tcp. */ #define IP6T_TCP_INV_SRCPT 0x01 /* Invert the sense of source ports. */ #define IP6T_TCP_INV_DSTPT 0x02 /* Invert the sense of dest ports. */ #define IP6T_TCP_INV_FLAGS 0x04 /* Invert the sense of TCP flags. */ #define IP6T_TCP_INV_OPTION 0x08 /* Invert the sense of option test. */ #define IP6T_TCP_INV_MASK 0x0F /* All possible flags. */ /* UDP matching stuff */ struct ip6t_udp { u_int16_t spts[2]; /* Source port range. */ u_int16_t dpts[2]; /* Destination port range. */ u_int8_t invflags; /* Inverse flags */ }; /* Values for "invflags" field in struct ipt_udp. */ #define IP6T_UDP_INV_SRCPT 0x01 /* Invert the sense of source ports. */ #define IP6T_UDP_INV_DSTPT 0x02 /* Invert the sense of dest ports. */ #define IP6T_UDP_INV_MASK 0x03 /* All possible flags. */ /* ICMP matching stuff */ struct ip6t_icmp { u_int8_t type; /* type to match */ u_int8_t code[2]; /* range of code */ u_int8_t invflags; /* Inverse flags */ }; /* Values for "inv" field for struct ipt_icmp. */ #define IP6T_ICMP_INV 0x01 /* Invert the sense of type/code test */ /* The argument to IP6T_SO_GET_INFO */ struct ip6t_getinfo { /* Which table: caller fills this in. */ char name[IP6T_TABLE_MAXNAMELEN]; /* Kernel fills these in. */ /* Which hook entry points are valid: bitmask */ unsigned int valid_hooks; /* Hook entry points: one per netfilter hook. */ unsigned int hook_entry[NF_IP6_NUMHOOKS]; /* Underflow points. */ unsigned int underflow[NF_IP6_NUMHOOKS]; /* Number of entries */ unsigned int num_entries; /* Size of entries. */ unsigned int size; }; /* The argument to IP6T_SO_SET_REPLACE. */ struct ip6t_replace { /* Which table. */ char name[IP6T_TABLE_MAXNAMELEN]; /* Which hook entry points are valid: bitmask. You can't change this. */ unsigned int valid_hooks; /* Number of entries */ unsigned int num_entries; /* Total size of new entries */ unsigned int size; /* Hook entry points. */ unsigned int hook_entry[NF_IP6_NUMHOOKS]; /* Underflow points. */ unsigned int underflow[NF_IP6_NUMHOOKS]; /* Information about old entries: */ /* Number of counters (must be equal to current number of entries). */ unsigned int num_counters; /* The old entries' counters. */ struct ip6t_counters __user *counters; /* The entries (hang off end: not really an array). */ struct ip6t_entry entries[0]; }; /* The argument to IP6T_SO_ADD_COUNTERS. */ struct ip6t_counters_info { /* Which table. */ char name[IP6T_TABLE_MAXNAMELEN]; unsigned int num_counters; /* The counters (actually `number' of these). */ struct ip6t_counters counters[0]; }; /* The argument to IP6T_SO_GET_ENTRIES. */ struct ip6t_get_entries { /* Which table: user fills this in. */ char name[IP6T_TABLE_MAXNAMELEN]; /* User fills this in: total entry size. */ unsigned int size; /* The entries. */ struct ip6t_entry entrytable[0]; }; /* The argument to IP6T_SO_GET_REVISION_*. Returns highest revision * kernel supports, if >= revision. */ struct ip6t_get_revision { char name[IP6T_FUNCTION_MAXNAMELEN-1]; u_int8_t revision; }; /* Standard return verdict, or do jump. */ #define IP6T_STANDARD_TARGET "" /* Error verdict. */ #define IP6T_ERROR_TARGET "ERROR" /* Helper functions */ static __inline__ struct ip6t_entry_target * ip6t_get_target(struct ip6t_entry *e) { return (void *)e + e->target_offset; } /* fn returns 0 to continue iteration */ #define IP6T_MATCH_ITERATE(e, fn, args...) \ ({ \ unsigned int __i; \ int __ret = 0; \ struct ip6t_entry_match *__m; \ \ for (__i = sizeof(struct ip6t_entry); \ __i < (e)->target_offset; \ __i += __m->u.match_size) { \ __m = (void *)(e) + __i; \ \ __ret = fn(__m , ## args); \ if (__ret != 0) \ break; \ } \ __ret; \ }) /* fn returns 0 to continue iteration */ #define IP6T_ENTRY_ITERATE(entries, size, fn, args...) \ ({ \ unsigned int __i; \ int __ret = 0; \ struct ip6t_entry *__e; \ \ for (__i = 0; __i < (size); __i += __e->next_offset) { \ __e = (void *)(entries) + __i; \ \ __ret = fn(__e , ## args); \ if (__ret != 0) \ break; \ } \ __ret; \ }) /* * Main firewall chains definitions and global var's definitions. */ #ifdef __KERNEL__ #include extern void ip6t_init(void) __init; struct ip6t_match { struct list_head list; const char name[IP6T_FUNCTION_MAXNAMELEN-1]; u_int8_t revision; /* Return true or false: return FALSE and set *hotdrop = 1 to force immediate packet drop. */ /* Arguments changed since 2.6.9, as this must now handle non-linear skb, using skb_header_pointer and skb_ip_make_writable. */ int (*match)(const struct sk_buff *skb, const struct net_device *in, const struct net_device *out, const void *matchinfo, int offset, unsigned int protoff, int *hotdrop); /* Called when user tries to insert an entry of this type. */ /* Should return true or false. */ int (*checkentry)(const char *tablename, const struct ip6t_ip6 *ip, void *matchinfo, unsigned int matchinfosize, unsigned int hook_mask); /* Called when entry of this type deleted. */ void (*destroy)(void *matchinfo, unsigned int matchinfosize); /* Set this to THIS_MODULE if you are a module, otherwise NULL */ struct module *me; }; /* Registration hooks for targets. */ struct ip6t_target { struct list_head list; const char name[IP6T_FUNCTION_MAXNAMELEN-1]; u_int8_t revision; /* Returns verdict. Argument order changed since 2.6.9, as this must now handle non-linear skbs, using skb_copy_bits and skb_ip_make_writable. */ unsigned int (*target)(struct sk_buff **pskb, const struct net_device *in, const struct net_device *out, unsigned int hooknum, const void *targinfo, void *userdata); /* Called when user tries to insert an entry of this type: hook_mask is a bitmask of hooks from which it can be called. */ /* Should return true or false. */ int (*checkentry)(const char *tablename, const struct ip6t_entry *e, void *targinfo, unsigned int targinfosize, unsigned int hook_mask); /* Called when entry of this type deleted. */ void (*destroy)(void *targinfo, unsigned int targinfosize); /* Set this to THIS_MODULE if you are a module, otherwise NULL */ struct module *me; }; extern int ip6t_register_target(struct ip6t_target *target); extern void ip6t_unregister_target(struct ip6t_target *target); extern int ip6t_register_match(struct ip6t_match *match); extern void ip6t_unregister_match(struct ip6t_match *match); /* Furniture shopping... */ struct ip6t_table { struct list_head list; /* A unique name... */ char name[IP6T_TABLE_MAXNAMELEN]; /* What hooks you will enter on */ unsigned int valid_hooks; /* Lock for the curtain */ rwlock_t lock; /* Man behind the curtain... */ struct ip6t_table_info *private; /* Set this to THIS_MODULE if you are a module, otherwise NULL */ struct module *me; }; extern int ip6t_register_table(struct ip6t_table *table, const struct ip6t_replace *repl); extern void ip6t_unregister_table(struct ip6t_table *table); extern unsigned int ip6t_do_table(struct sk_buff **pskb, unsigned int hook, const struct net_device *in, const struct net_device *out, struct ip6t_table *table, void *userdata); /* Check for an extension */ extern int ip6t_ext_hdr(u8 nexthdr); /* find specified header and get offset to it */ extern int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset, int target, unsigned short *fragoff); extern int ip6_masked_addrcmp(const struct in6_addr *addr1, const struct in6_addr *mask, const struct in6_addr *addr2); #define IP6T_ALIGN(s) (((s) + (__alignof__(struct ip6t_entry)-1)) & ~(__alignof__(struct ip6t_entry)-1)) #endif /*__KERNEL__*/ #endif /* _IP6_TABLES_H */