xref: /linux/include/uapi/linux/filter.h (revision 498495dba268b20e8eadd7fe93c140c68b6cc9d2)
1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2 /*
3  * Linux Socket Filter Data Structures
4  */
5 
6 #ifndef _UAPI__LINUX_FILTER_H__
7 #define _UAPI__LINUX_FILTER_H__
8 
9 #include <linux/compiler.h>
10 #include <linux/types.h>
11 #include <linux/bpf_common.h>
12 
13 /*
14  * Current version of the filter code architecture.
15  */
16 #define BPF_MAJOR_VERSION 1
17 #define BPF_MINOR_VERSION 1
18 
19 /*
20  *	Try and keep these values and structures similar to BSD, especially
21  *	the BPF code definitions which need to match so you can share filters
22  */
23 
24 struct sock_filter {	/* Filter block */
25 	__u16	code;   /* Actual filter code */
26 	__u8	jt;	/* Jump true */
27 	__u8	jf;	/* Jump false */
28 	__u32	k;      /* Generic multiuse field */
29 };
30 
31 struct sock_fprog {	/* Required for SO_ATTACH_FILTER. */
32 	unsigned short		len;	/* Number of filter blocks */
33 	struct sock_filter __user *filter;
34 };
35 
36 /* ret - BPF_K and BPF_X also apply */
37 #define BPF_RVAL(code)  ((code) & 0x18)
38 #define         BPF_A           0x10
39 
40 /* misc */
41 #define BPF_MISCOP(code) ((code) & 0xf8)
42 #define         BPF_TAX         0x00
43 #define         BPF_TXA         0x80
44 
45 /*
46  * Macros for filter block array initializers.
47  */
48 #ifndef BPF_STMT
49 #define BPF_STMT(code, k) { (unsigned short)(code), 0, 0, k }
50 #endif
51 #ifndef BPF_JUMP
52 #define BPF_JUMP(code, k, jt, jf) { (unsigned short)(code), jt, jf, k }
53 #endif
54 
55 /*
56  * Number of scratch memory words for: BPF_ST and BPF_STX
57  */
58 #define BPF_MEMWORDS 16
59 
60 /* RATIONALE. Negative offsets are invalid in BPF.
61    We use them to reference ancillary data.
62    Unlike introduction new instructions, it does not break
63    existing compilers/optimizers.
64  */
65 #define SKF_AD_OFF    (-0x1000)
66 #define SKF_AD_PROTOCOL 0
67 #define SKF_AD_PKTTYPE 	4
68 #define SKF_AD_IFINDEX 	8
69 #define SKF_AD_NLATTR	12
70 #define SKF_AD_NLATTR_NEST	16
71 #define SKF_AD_MARK 	20
72 #define SKF_AD_QUEUE	24
73 #define SKF_AD_HATYPE	28
74 #define SKF_AD_RXHASH	32
75 #define SKF_AD_CPU	36
76 #define SKF_AD_ALU_XOR_X	40
77 #define SKF_AD_VLAN_TAG	44
78 #define SKF_AD_VLAN_TAG_PRESENT 48
79 #define SKF_AD_PAY_OFFSET	52
80 #define SKF_AD_RANDOM	56
81 #define SKF_AD_VLAN_TPID	60
82 #define SKF_AD_MAX	64
83 
84 #define SKF_NET_OFF	(-0x100000)
85 #define SKF_LL_OFF	(-0x200000)
86 
87 #define BPF_NET_OFF	SKF_NET_OFF
88 #define BPF_LL_OFF	SKF_LL_OFF
89 
90 #endif /* _UAPI__LINUX_FILTER_H__ */
91