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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /include/linux/netfilter/x_tables.h
Initial import
Diffstat (limited to 'include/linux/netfilter/x_tables.h')
-rw-r--r--include/linux/netfilter/x_tables.h436
1 files changed, 436 insertions, 0 deletions
diff --git a/include/linux/netfilter/x_tables.h b/include/linux/netfilter/x_tables.h
new file mode 100644
index 000000000..a3e215bb0
--- /dev/null
+++ b/include/linux/netfilter/x_tables.h
@@ -0,0 +1,436 @@
+#ifndef _X_TABLES_H
+#define _X_TABLES_H
+
+
+#include <linux/netdevice.h>
+#include <uapi/linux/netfilter/x_tables.h>
+
+/**
+ * struct xt_action_param - parameters for matches/targets
+ *
+ * @match: the match extension
+ * @target: the target extension
+ * @matchinfo: per-match data
+ * @targetinfo: per-target data
+ * @in: input netdevice
+ * @out: output netdevice
+ * @fragoff: packet is a fragment, this is the data offset
+ * @thoff: position of transport header relative to skb->data
+ * @hook: hook number given packet came from
+ * @family: Actual NFPROTO_* through which the function is invoked
+ * (helpful when match->family == NFPROTO_UNSPEC)
+ *
+ * Fields written to by extensions:
+ *
+ * @hotdrop: drop packet if we had inspection problems
+ * Network namespace obtainable using dev_net(in/out)
+ */
+struct xt_action_param {
+ union {
+ const struct xt_match *match;
+ const struct xt_target *target;
+ };
+ union {
+ const void *matchinfo, *targinfo;
+ };
+ const struct net_device *in, *out;
+ int fragoff;
+ unsigned int thoff;
+ unsigned int hooknum;
+ u_int8_t family;
+ bool hotdrop;
+};
+
+/**
+ * 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;
+};
+
+/**
+ * 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;
+};
+
+/* 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_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;
+#ifdef CONFIG_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_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;
+#ifdef CONFIG_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;
+
+ /* 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 <linux/netfilter_ipv4.h>
+
+/* 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;
+ unsigned int __percpu *stackptr;
+ void ***jumpstack;
+ /* ipt_entry tables: one per CPU */
+ /* Note : this field MUST be the last one, see XT_TABLE_INFO_SZ */
+ void *entries[1];
+};
+
+#define XT_TABLE_INFO_SZ (offsetof(struct xt_table_info, entries) \
+ + nr_cpu_ids * sizeof(char *))
+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_match(struct xt_mtchk_param *, unsigned int size, u_int8_t proto,
+ bool inv_proto);
+int xt_check_target(struct xt_tgchk_param *, unsigned int size, u_int8_t proto,
+ bool inv_proto);
+
+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_target *xt_find_target(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_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_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_wmb();
+
+ 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 nf_hook_ops *xt_hook_link(const struct xt_table *, nf_hookfn *);
+void xt_hook_unlink(const struct xt_table *, struct nf_hook_ops *);
+
+#ifdef CONFIG_COMPAT
+#include <net/compat.h>
+
+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[0];
+};
+
+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[0];
+};
+
+/* 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[0];
+};
+
+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);
+void xt_compat_init_offsets(u_int8_t 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);
+int 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);
+
+#endif /* CONFIG_COMPAT */
+#endif /* _X_TABLES_H */