From 2c3c1048746a4622d8c89a29670120dc8fab93c4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 20:49:45 +0200 Subject: Adding upstream version 6.1.76. Signed-off-by: Daniel Baumann --- include/linux/netfilter/x_tables.h | 537 +++++++++++++++++++++++++++++++++++++ 1 file changed, 537 insertions(+) create mode 100644 include/linux/netfilter/x_tables.h (limited to 'include/linux/netfilter/x_tables.h') diff --git a/include/linux/netfilter/x_tables.h b/include/linux/netfilter/x_tables.h new file mode 100644 index 000000000..5897f3dba --- /dev/null +++ b/include/linux/netfilter/x_tables.h @@ -0,0 +1,537 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _X_TABLES_H +#define _X_TABLES_H + + +#include +#include +#include +#include + +/* Test a struct->invflags and a boolean for inequality */ +#define NF_INVF(ptr, flag, boolean) \ + ((boolean) ^ !!((ptr)->invflags & (flag))) + +/** + * struct xt_action_param - parameters for matches/targets + * + * @match: the match extension + * @target: the target extension + * @matchinfo: per-match data + * @targetinfo: per-target data + * @state: pointer to hook state this packet came from + * @fragoff: packet is a fragment, this is the data offset + * @thoff: position of transport header relative to skb->data + * + * Fields written to by extensions: + * + * @hotdrop: drop packet if we had inspection problems + */ +struct xt_action_param { + union { + const struct xt_match *match; + const struct xt_target *target; + }; + union { + const void *matchinfo, *targinfo; + }; + const struct nf_hook_state *state; + unsigned int thoff; + u16 fragoff; + bool hotdrop; +}; + +static inline struct net *xt_net(const struct xt_action_param *par) +{ + return par->state->net; +} + +static inline struct net_device *xt_in(const struct xt_action_param *par) +{ + return par->state->in; +} + +static inline const char *xt_inname(const struct xt_action_param *par) +{ + return par->state->in->name; +} + +static inline struct net_device *xt_out(const struct xt_action_param *par) +{ + return par->state->out; +} + +static inline const char *xt_outname(const struct xt_action_param *par) +{ + return par->state->out->name; +} + +static inline unsigned int xt_hooknum(const struct xt_action_param *par) +{ + return par->state->hook; +} + +static inline u_int8_t xt_family(const struct xt_action_param *par) +{ + return par->state->pf; +} + +/** + * struct xt_mtchk_param - parameters for match extensions' + * checkentry functions + * + * @net: network namespace through which the check was invoked + * @table: table the rule is tried to be inserted into + * @entryinfo: the family-specific rule data + * (struct ipt_ip, ip6t_ip, arpt_arp or (note) ebt_entry) + * @match: struct xt_match through which this function was invoked + * @matchinfo: per-match data + * @hook_mask: via which hooks the new rule is reachable + * Other fields as above. + */ +struct xt_mtchk_param { + struct net *net; + const char *table; + const void *entryinfo; + const struct xt_match *match; + void *matchinfo; + unsigned int hook_mask; + u_int8_t family; + bool nft_compat; +}; + +/** + * struct xt_mdtor_param - match destructor parameters + * Fields as above. + */ +struct xt_mtdtor_param { + struct net *net; + const struct xt_match *match; + void *matchinfo; + u_int8_t family; +}; + +/** + * struct xt_tgchk_param - parameters for target extensions' + * checkentry functions + * + * @entryinfo: the family-specific rule data + * (struct ipt_entry, ip6t_entry, arpt_entry, ebt_entry) + * + * Other fields see above. + */ +struct xt_tgchk_param { + struct net *net; + const char *table; + const void *entryinfo; + const struct xt_target *target; + void *targinfo; + unsigned int hook_mask; + u_int8_t family; + bool nft_compat; +}; + +/* Target destructor parameters */ +struct xt_tgdtor_param { + struct net *net; + const struct xt_target *target; + void *targinfo; + u_int8_t family; +}; + +struct xt_match { + struct list_head list; + + const char name[XT_EXTENSION_MAXNAMELEN]; + 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. */ + bool (*match)(const struct sk_buff *skb, + struct xt_action_param *); + + /* Called when user tries to insert an entry of this type. */ + int (*checkentry)(const struct xt_mtchk_param *); + + /* Called when entry of this type deleted. */ + void (*destroy)(const struct xt_mtdtor_param *); +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT + /* Called when userspace align differs from kernel space one */ + void (*compat_from_user)(void *dst, const void *src); + int (*compat_to_user)(void __user *dst, const void *src); +#endif + /* Set this to THIS_MODULE if you are a module, otherwise NULL */ + struct module *me; + + const char *table; + unsigned int matchsize; + unsigned int usersize; +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT + unsigned int compatsize; +#endif + unsigned int hooks; + unsigned short proto; + + unsigned short family; +}; + +/* Registration hooks for targets. */ +struct xt_target { + struct list_head list; + + const char name[XT_EXTENSION_MAXNAMELEN]; + 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 *skb, + const struct xt_action_param *); + + /* 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 0 on success or an error code otherwise (-Exxxx). */ + int (*checkentry)(const struct xt_tgchk_param *); + + /* Called when entry of this type deleted. */ + void (*destroy)(const struct xt_tgdtor_param *); +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT + /* Called when userspace align differs from kernel space one */ + void (*compat_from_user)(void *dst, const void *src); + int (*compat_to_user)(void __user *dst, const void *src); +#endif + /* Set this to THIS_MODULE if you are a module, otherwise NULL */ + struct module *me; + + const char *table; + unsigned int targetsize; + unsigned int usersize; +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT + unsigned int compatsize; +#endif + unsigned int hooks; + unsigned short proto; + + unsigned short family; +}; + +/* Furniture shopping... */ +struct xt_table { + struct list_head list; + + /* What hooks you will enter on */ + unsigned int valid_hooks; + + /* Man behind the curtain... */ + struct xt_table_info *private; + + /* hook ops that register the table with the netfilter core */ + struct nf_hook_ops *ops; + + /* Set this to THIS_MODULE if you are a module, otherwise NULL */ + struct module *me; + + u_int8_t af; /* address/protocol family */ + int priority; /* hook order */ + + /* A unique name... */ + const char name[XT_TABLE_MAXNAMELEN]; +}; + +#include + +/* The table itself */ +struct xt_table_info { + /* Size per table */ + unsigned int size; + /* Number of entries: FIXME. --RR */ + unsigned int number; + /* Initial number of entries. Needed for module usage count */ + unsigned int initial_entries; + + /* Entry points and underflows */ + unsigned int hook_entry[NF_INET_NUMHOOKS]; + unsigned int underflow[NF_INET_NUMHOOKS]; + + /* + * Number of user chains. Since tables cannot have loops, at most + * @stacksize jumps (number of user chains) can possibly be made. + */ + unsigned int stacksize; + void ***jumpstack; + + unsigned char entries[] __aligned(8); +}; + +int xt_register_target(struct xt_target *target); +void xt_unregister_target(struct xt_target *target); +int xt_register_targets(struct xt_target *target, unsigned int n); +void xt_unregister_targets(struct xt_target *target, unsigned int n); + +int xt_register_match(struct xt_match *target); +void xt_unregister_match(struct xt_match *target); +int xt_register_matches(struct xt_match *match, unsigned int n); +void xt_unregister_matches(struct xt_match *match, unsigned int n); + +int xt_check_entry_offsets(const void *base, const char *elems, + unsigned int target_offset, + unsigned int next_offset); + +int xt_check_table_hooks(const struct xt_table_info *info, unsigned int valid_hooks); + +unsigned int *xt_alloc_entry_offsets(unsigned int size); +bool xt_find_jump_offset(const unsigned int *offsets, + unsigned int target, unsigned int size); + +int xt_check_proc_name(const char *name, unsigned int size); + +int xt_check_match(struct xt_mtchk_param *, unsigned int size, u16 proto, + bool inv_proto); +int xt_check_target(struct xt_tgchk_param *, unsigned int size, u16 proto, + bool inv_proto); + +int xt_match_to_user(const struct xt_entry_match *m, + struct xt_entry_match __user *u); +int xt_target_to_user(const struct xt_entry_target *t, + struct xt_entry_target __user *u); +int xt_data_to_user(void __user *dst, const void *src, + int usersize, int size, int aligned_size); + +void *xt_copy_counters(sockptr_t arg, unsigned int len, + struct xt_counters_info *info); +struct xt_counters *xt_counters_alloc(unsigned int counters); + +struct xt_table *xt_register_table(struct net *net, + const struct xt_table *table, + struct xt_table_info *bootstrap, + struct xt_table_info *newinfo); +void *xt_unregister_table(struct xt_table *table); + +struct xt_table_info *xt_replace_table(struct xt_table *table, + unsigned int num_counters, + struct xt_table_info *newinfo, + int *error); + +struct xt_match *xt_find_match(u8 af, const char *name, u8 revision); +struct xt_match *xt_request_find_match(u8 af, const char *name, u8 revision); +struct xt_target *xt_request_find_target(u8 af, const char *name, u8 revision); +int xt_find_revision(u8 af, const char *name, u8 revision, int target, + int *err); + +struct xt_table *xt_find_table(struct net *net, u8 af, const char *name); +struct xt_table *xt_find_table_lock(struct net *net, u_int8_t af, + const char *name); +struct xt_table *xt_request_find_table_lock(struct net *net, u_int8_t af, + const char *name); +void xt_table_unlock(struct xt_table *t); + +int xt_proto_init(struct net *net, u_int8_t af); +void xt_proto_fini(struct net *net, u_int8_t af); + +struct xt_table_info *xt_alloc_table_info(unsigned int size); +void xt_free_table_info(struct xt_table_info *info); + +/** + * xt_recseq - recursive seqcount for netfilter use + * + * Packet processing changes the seqcount only if no recursion happened + * get_counters() can use read_seqcount_begin()/read_seqcount_retry(), + * because we use the normal seqcount convention : + * Low order bit set to 1 if a writer is active. + */ +DECLARE_PER_CPU(seqcount_t, xt_recseq); + +/* xt_tee_enabled - true if x_tables needs to handle reentrancy + * + * Enabled if current ip(6)tables ruleset has at least one -j TEE rule. + */ +extern struct static_key xt_tee_enabled; + +/** + * xt_write_recseq_begin - start of a write section + * + * Begin packet processing : all readers must wait the end + * 1) Must be called with preemption disabled + * 2) softirqs must be disabled too (or we should use this_cpu_add()) + * Returns : + * 1 if no recursion on this cpu + * 0 if recursion detected + */ +static inline unsigned int xt_write_recseq_begin(void) +{ + unsigned int addend; + + /* + * Low order bit of sequence is set if we already + * called xt_write_recseq_begin(). + */ + addend = (__this_cpu_read(xt_recseq.sequence) + 1) & 1; + + /* + * This is kind of a write_seqcount_begin(), but addend is 0 or 1 + * We dont check addend value to avoid a test and conditional jump, + * since addend is most likely 1 + */ + __this_cpu_add(xt_recseq.sequence, addend); + smp_mb(); + + return addend; +} + +/** + * xt_write_recseq_end - end of a write section + * @addend: return value from previous xt_write_recseq_begin() + * + * End packet processing : all readers can proceed + * 1) Must be called with preemption disabled + * 2) softirqs must be disabled too (or we should use this_cpu_add()) + */ +static inline void xt_write_recseq_end(unsigned int addend) +{ + /* this is kind of a write_seqcount_end(), but addend is 0 or 1 */ + smp_wmb(); + __this_cpu_add(xt_recseq.sequence, addend); +} + +/* + * This helper is performance critical and must be inlined + */ +static inline unsigned long ifname_compare_aligned(const char *_a, + const char *_b, + const char *_mask) +{ + const unsigned long *a = (const unsigned long *)_a; + const unsigned long *b = (const unsigned long *)_b; + const unsigned long *mask = (const unsigned long *)_mask; + unsigned long ret; + + ret = (a[0] ^ b[0]) & mask[0]; + if (IFNAMSIZ > sizeof(unsigned long)) + ret |= (a[1] ^ b[1]) & mask[1]; + if (IFNAMSIZ > 2 * sizeof(unsigned long)) + ret |= (a[2] ^ b[2]) & mask[2]; + if (IFNAMSIZ > 3 * sizeof(unsigned long)) + ret |= (a[3] ^ b[3]) & mask[3]; + BUILD_BUG_ON(IFNAMSIZ > 4 * sizeof(unsigned long)); + return ret; +} + +struct xt_percpu_counter_alloc_state { + unsigned int off; + const char __percpu *mem; +}; + +bool xt_percpu_counter_alloc(struct xt_percpu_counter_alloc_state *state, + struct xt_counters *counter); +void xt_percpu_counter_free(struct xt_counters *cnt); + +static inline struct xt_counters * +xt_get_this_cpu_counter(struct xt_counters *cnt) +{ + if (nr_cpu_ids > 1) + return this_cpu_ptr((void __percpu *) (unsigned long) cnt->pcnt); + + return cnt; +} + +static inline struct xt_counters * +xt_get_per_cpu_counter(struct xt_counters *cnt, unsigned int cpu) +{ + if (nr_cpu_ids > 1) + return per_cpu_ptr((void __percpu *) (unsigned long) cnt->pcnt, cpu); + + return cnt; +} + +struct nf_hook_ops *xt_hook_ops_alloc(const struct xt_table *, nf_hookfn *); + +int xt_register_template(const struct xt_table *t, int(*table_init)(struct net *net)); +void xt_unregister_template(const struct xt_table *t); + +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT +#include + +struct compat_xt_entry_match { + union { + struct { + u_int16_t match_size; + char name[XT_FUNCTION_MAXNAMELEN - 1]; + u_int8_t revision; + } user; + struct { + u_int16_t match_size; + compat_uptr_t match; + } kernel; + u_int16_t match_size; + } u; + unsigned char data[]; +}; + +struct compat_xt_entry_target { + union { + struct { + u_int16_t target_size; + char name[XT_FUNCTION_MAXNAMELEN - 1]; + u_int8_t revision; + } user; + struct { + u_int16_t target_size; + compat_uptr_t target; + } kernel; + u_int16_t target_size; + } u; + unsigned char data[]; +}; + +/* FIXME: this works only on 32 bit tasks + * need to change whole approach in order to calculate align as function of + * current task alignment */ + +struct compat_xt_counters { + compat_u64 pcnt, bcnt; /* Packet and byte counters */ +}; + +struct compat_xt_counters_info { + char name[XT_TABLE_MAXNAMELEN]; + compat_uint_t num_counters; + struct compat_xt_counters counters[]; +}; + +struct _compat_xt_align { + __u8 u8; + __u16 u16; + __u32 u32; + compat_u64 u64; +}; + +#define COMPAT_XT_ALIGN(s) __ALIGN_KERNEL((s), __alignof__(struct _compat_xt_align)) + +void xt_compat_lock(u_int8_t af); +void xt_compat_unlock(u_int8_t af); + +int xt_compat_add_offset(u_int8_t af, unsigned int offset, int delta); +void xt_compat_flush_offsets(u_int8_t af); +int xt_compat_init_offsets(u8 af, unsigned int number); +int xt_compat_calc_jump(u_int8_t af, unsigned int offset); + +int xt_compat_match_offset(const struct xt_match *match); +void xt_compat_match_from_user(struct xt_entry_match *m, void **dstptr, + unsigned int *size); +int xt_compat_match_to_user(const struct xt_entry_match *m, + void __user **dstptr, unsigned int *size); + +int xt_compat_target_offset(const struct xt_target *target); +void xt_compat_target_from_user(struct xt_entry_target *t, void **dstptr, + unsigned int *size); +int xt_compat_target_to_user(const struct xt_entry_target *t, + void __user **dstptr, unsigned int *size); +int xt_compat_check_entry_offsets(const void *base, const char *elems, + unsigned int target_offset, + unsigned int next_offset); + +#endif /* CONFIG_NETFILTER_XTABLES_COMPAT */ +#endif /* _X_TABLES_H */ -- cgit v1.2.3