xref: /linux-6.15/include/linux/filter.h (revision e756bc56)
1 /*
2  * Linux Socket Filter Data Structures
3  */
4 #ifndef __LINUX_FILTER_H__
5 #define __LINUX_FILTER_H__
6 
7 #include <linux/atomic.h>
8 #include <linux/compat.h>
9 #include <linux/workqueue.h>
10 #include <uapi/linux/filter.h>
11 
12 #ifdef CONFIG_COMPAT
13 /*
14  * A struct sock_filter is architecture independent.
15  */
16 struct compat_sock_fprog {
17 	u16		len;
18 	compat_uptr_t	filter;		/* struct sock_filter * */
19 };
20 #endif
21 
22 struct sk_buff;
23 struct sock;
24 
25 struct sk_filter
26 {
27 	atomic_t		refcnt;
28 	unsigned int         	len;	/* Number of filter blocks */
29 	struct rcu_head		rcu;
30 	unsigned int		(*bpf_func)(const struct sk_buff *skb,
31 					    const struct sock_filter *filter);
32 	union {
33 		struct sock_filter     	insns[0];
34 		struct work_struct	work;
35 	};
36 };
37 
38 static inline unsigned int sk_filter_size(unsigned int proglen)
39 {
40 	return max(sizeof(struct sk_filter),
41 		   offsetof(struct sk_filter, insns[proglen]));
42 }
43 
44 extern int sk_filter(struct sock *sk, struct sk_buff *skb);
45 extern unsigned int sk_run_filter(const struct sk_buff *skb,
46 				  const struct sock_filter *filter);
47 extern int sk_unattached_filter_create(struct sk_filter **pfp,
48 				       struct sock_fprog *fprog);
49 extern void sk_unattached_filter_destroy(struct sk_filter *fp);
50 extern int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk);
51 extern int sk_detach_filter(struct sock *sk);
52 extern int sk_chk_filter(struct sock_filter *filter, unsigned int flen);
53 extern int sk_get_filter(struct sock *sk, struct sock_filter __user *filter, unsigned len);
54 extern void sk_decode_filter(struct sock_filter *filt, struct sock_filter *to);
55 
56 #ifdef CONFIG_BPF_JIT
57 #include <stdarg.h>
58 #include <linux/linkage.h>
59 #include <linux/printk.h>
60 
61 extern void bpf_jit_compile(struct sk_filter *fp);
62 extern void bpf_jit_free(struct sk_filter *fp);
63 
64 static inline void bpf_jit_dump(unsigned int flen, unsigned int proglen,
65 				u32 pass, void *image)
66 {
67 	pr_err("flen=%u proglen=%u pass=%u image=%pK\n",
68 	       flen, proglen, pass, image);
69 	if (image)
70 		print_hex_dump(KERN_ERR, "JIT code: ", DUMP_PREFIX_OFFSET,
71 			       16, 1, image, proglen, false);
72 }
73 #define SK_RUN_FILTER(FILTER, SKB) (*FILTER->bpf_func)(SKB, FILTER->insns)
74 #else
75 #include <linux/slab.h>
76 static inline void bpf_jit_compile(struct sk_filter *fp)
77 {
78 }
79 static inline void bpf_jit_free(struct sk_filter *fp)
80 {
81 	kfree(fp);
82 }
83 #define SK_RUN_FILTER(FILTER, SKB) sk_run_filter(SKB, FILTER->insns)
84 #endif
85 
86 enum {
87 	BPF_S_RET_K = 1,
88 	BPF_S_RET_A,
89 	BPF_S_ALU_ADD_K,
90 	BPF_S_ALU_ADD_X,
91 	BPF_S_ALU_SUB_K,
92 	BPF_S_ALU_SUB_X,
93 	BPF_S_ALU_MUL_K,
94 	BPF_S_ALU_MUL_X,
95 	BPF_S_ALU_DIV_X,
96 	BPF_S_ALU_MOD_K,
97 	BPF_S_ALU_MOD_X,
98 	BPF_S_ALU_AND_K,
99 	BPF_S_ALU_AND_X,
100 	BPF_S_ALU_OR_K,
101 	BPF_S_ALU_OR_X,
102 	BPF_S_ALU_XOR_K,
103 	BPF_S_ALU_XOR_X,
104 	BPF_S_ALU_LSH_K,
105 	BPF_S_ALU_LSH_X,
106 	BPF_S_ALU_RSH_K,
107 	BPF_S_ALU_RSH_X,
108 	BPF_S_ALU_NEG,
109 	BPF_S_LD_W_ABS,
110 	BPF_S_LD_H_ABS,
111 	BPF_S_LD_B_ABS,
112 	BPF_S_LD_W_LEN,
113 	BPF_S_LD_W_IND,
114 	BPF_S_LD_H_IND,
115 	BPF_S_LD_B_IND,
116 	BPF_S_LD_IMM,
117 	BPF_S_LDX_W_LEN,
118 	BPF_S_LDX_B_MSH,
119 	BPF_S_LDX_IMM,
120 	BPF_S_MISC_TAX,
121 	BPF_S_MISC_TXA,
122 	BPF_S_ALU_DIV_K,
123 	BPF_S_LD_MEM,
124 	BPF_S_LDX_MEM,
125 	BPF_S_ST,
126 	BPF_S_STX,
127 	BPF_S_JMP_JA,
128 	BPF_S_JMP_JEQ_K,
129 	BPF_S_JMP_JEQ_X,
130 	BPF_S_JMP_JGE_K,
131 	BPF_S_JMP_JGE_X,
132 	BPF_S_JMP_JGT_K,
133 	BPF_S_JMP_JGT_X,
134 	BPF_S_JMP_JSET_K,
135 	BPF_S_JMP_JSET_X,
136 	/* Ancillary data */
137 	BPF_S_ANC_PROTOCOL,
138 	BPF_S_ANC_PKTTYPE,
139 	BPF_S_ANC_IFINDEX,
140 	BPF_S_ANC_NLATTR,
141 	BPF_S_ANC_NLATTR_NEST,
142 	BPF_S_ANC_MARK,
143 	BPF_S_ANC_QUEUE,
144 	BPF_S_ANC_HATYPE,
145 	BPF_S_ANC_RXHASH,
146 	BPF_S_ANC_CPU,
147 	BPF_S_ANC_ALU_XOR_X,
148 	BPF_S_ANC_SECCOMP_LD_W,
149 	BPF_S_ANC_VLAN_TAG,
150 	BPF_S_ANC_VLAN_TAG_PRESENT,
151 	BPF_S_ANC_PAY_OFFSET,
152 };
153 
154 #endif /* __LINUX_FILTER_H__ */
155