Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Linux Socket Filter Data Structures |
| 3 | */ |
| 4 | |
| 5 | #ifndef __LINUX_FILTER_H__ |
| 6 | #define __LINUX_FILTER_H__ |
| 7 | |
| 8 | #include <linux/compiler.h> |
| 9 | #include <linux/types.h> |
| 10 | |
| 11 | #ifdef __KERNEL__ |
Arun Sharma | 60063497 | 2011-07-26 16:09:06 -0700 | [diff] [blame] | 12 | #include <linux/atomic.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 13 | #endif |
| 14 | |
| 15 | /* |
| 16 | * Current version of the filter code architecture. |
| 17 | */ |
| 18 | #define BPF_MAJOR_VERSION 1 |
| 19 | #define BPF_MINOR_VERSION 1 |
| 20 | |
| 21 | /* |
| 22 | * Try and keep these values and structures similar to BSD, especially |
| 23 | * the BPF code definitions which need to match so you can share filters |
| 24 | */ |
| 25 | |
Eric Dumazet | d94d9fe | 2009-11-04 09:50:58 -0800 | [diff] [blame] | 26 | struct sock_filter { /* Filter block */ |
Dmitry Mishin | fda9ef5 | 2006-08-31 15:28:39 -0700 | [diff] [blame] | 27 | __u16 code; /* Actual filter code */ |
| 28 | __u8 jt; /* Jump true */ |
| 29 | __u8 jf; /* Jump false */ |
| 30 | __u32 k; /* Generic multiuse field */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 31 | }; |
| 32 | |
Eric Dumazet | d94d9fe | 2009-11-04 09:50:58 -0800 | [diff] [blame] | 33 | struct sock_fprog { /* Required for SO_ATTACH_FILTER. */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 34 | unsigned short len; /* Number of filter blocks */ |
| 35 | struct sock_filter __user *filter; |
| 36 | }; |
| 37 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 38 | /* |
| 39 | * Instruction classes |
| 40 | */ |
| 41 | |
| 42 | #define BPF_CLASS(code) ((code) & 0x07) |
| 43 | #define BPF_LD 0x00 |
| 44 | #define BPF_LDX 0x01 |
| 45 | #define BPF_ST 0x02 |
| 46 | #define BPF_STX 0x03 |
| 47 | #define BPF_ALU 0x04 |
| 48 | #define BPF_JMP 0x05 |
| 49 | #define BPF_RET 0x06 |
| 50 | #define BPF_MISC 0x07 |
| 51 | |
| 52 | /* ld/ldx fields */ |
| 53 | #define BPF_SIZE(code) ((code) & 0x18) |
| 54 | #define BPF_W 0x00 |
| 55 | #define BPF_H 0x08 |
| 56 | #define BPF_B 0x10 |
| 57 | #define BPF_MODE(code) ((code) & 0xe0) |
| 58 | #define BPF_IMM 0x00 |
| 59 | #define BPF_ABS 0x20 |
| 60 | #define BPF_IND 0x40 |
| 61 | #define BPF_MEM 0x60 |
| 62 | #define BPF_LEN 0x80 |
| 63 | #define BPF_MSH 0xa0 |
| 64 | |
| 65 | /* alu/jmp fields */ |
| 66 | #define BPF_OP(code) ((code) & 0xf0) |
| 67 | #define BPF_ADD 0x00 |
| 68 | #define BPF_SUB 0x10 |
| 69 | #define BPF_MUL 0x20 |
| 70 | #define BPF_DIV 0x30 |
| 71 | #define BPF_OR 0x40 |
| 72 | #define BPF_AND 0x50 |
| 73 | #define BPF_LSH 0x60 |
| 74 | #define BPF_RSH 0x70 |
| 75 | #define BPF_NEG 0x80 |
| 76 | #define BPF_JA 0x00 |
| 77 | #define BPF_JEQ 0x10 |
| 78 | #define BPF_JGT 0x20 |
| 79 | #define BPF_JGE 0x30 |
| 80 | #define BPF_JSET 0x40 |
| 81 | #define BPF_SRC(code) ((code) & 0x08) |
| 82 | #define BPF_K 0x00 |
| 83 | #define BPF_X 0x08 |
| 84 | |
| 85 | /* ret - BPF_K and BPF_X also apply */ |
| 86 | #define BPF_RVAL(code) ((code) & 0x18) |
| 87 | #define BPF_A 0x10 |
| 88 | |
| 89 | /* misc */ |
| 90 | #define BPF_MISCOP(code) ((code) & 0xf8) |
| 91 | #define BPF_TAX 0x00 |
| 92 | #define BPF_TXA 0x80 |
| 93 | |
| 94 | #ifndef BPF_MAXINSNS |
| 95 | #define BPF_MAXINSNS 4096 |
| 96 | #endif |
| 97 | |
| 98 | /* |
| 99 | * Macros for filter block array initializers. |
| 100 | */ |
| 101 | #ifndef BPF_STMT |
| 102 | #define BPF_STMT(code, k) { (unsigned short)(code), 0, 0, k } |
| 103 | #endif |
| 104 | #ifndef BPF_JUMP |
| 105 | #define BPF_JUMP(code, k, jt, jf) { (unsigned short)(code), jt, jf, k } |
| 106 | #endif |
| 107 | |
| 108 | /* |
| 109 | * Number of scratch memory words for: BPF_ST and BPF_STX |
| 110 | */ |
| 111 | #define BPF_MEMWORDS 16 |
| 112 | |
| 113 | /* RATIONALE. Negative offsets are invalid in BPF. |
| 114 | We use them to reference ancillary data. |
| 115 | Unlike introduction new instructions, it does not break |
| 116 | existing compilers/optimizers. |
| 117 | */ |
| 118 | #define SKF_AD_OFF (-0x1000) |
| 119 | #define SKF_AD_PROTOCOL 0 |
| 120 | #define SKF_AD_PKTTYPE 4 |
| 121 | #define SKF_AD_IFINDEX 8 |
Patrick McHardy | 4738c1d | 2008-04-10 02:02:28 -0700 | [diff] [blame] | 122 | #define SKF_AD_NLATTR 12 |
Pablo Neira Ayuso | d214c75 | 2008-11-20 00:49:27 -0800 | [diff] [blame] | 123 | #define SKF_AD_NLATTR_NEST 16 |
jamal | 7e75f93 | 2009-10-19 02:17:56 +0000 | [diff] [blame] | 124 | #define SKF_AD_MARK 20 |
Eric Dumazet | d19742f | 2009-10-20 01:06:22 -0700 | [diff] [blame] | 125 | #define SKF_AD_QUEUE 24 |
Paul LeoNerd Evans | 40eaf96 | 2010-04-22 03:32:22 +0000 | [diff] [blame] | 126 | #define SKF_AD_HATYPE 28 |
Eric Dumazet | da2033c | 2010-11-30 21:45:56 +0000 | [diff] [blame] | 127 | #define SKF_AD_RXHASH 32 |
| 128 | #define SKF_AD_CPU 36 |
| 129 | #define SKF_AD_MAX 40 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 130 | #define SKF_NET_OFF (-0x100000) |
| 131 | #define SKF_LL_OFF (-0x200000) |
| 132 | |
| 133 | #ifdef __KERNEL__ |
Heiko Carstens | 792d4b5 | 2011-05-22 07:08:11 +0000 | [diff] [blame] | 134 | |
| 135 | struct sk_buff; |
| 136 | struct sock; |
| 137 | |
Stephen Hemminger | b715631 | 2008-04-10 01:33:47 -0700 | [diff] [blame] | 138 | struct sk_filter |
| 139 | { |
| 140 | atomic_t refcnt; |
| 141 | unsigned int len; /* Number of filter blocks */ |
Eric Dumazet | 0a14842 | 2011-04-20 09:27:32 +0000 | [diff] [blame] | 142 | unsigned int (*bpf_func)(const struct sk_buff *skb, |
| 143 | const struct sock_filter *filter); |
Stephen Hemminger | b715631 | 2008-04-10 01:33:47 -0700 | [diff] [blame] | 144 | struct rcu_head rcu; |
| 145 | struct sock_filter insns[0]; |
| 146 | }; |
| 147 | |
| 148 | static inline unsigned int sk_filter_len(const struct sk_filter *fp) |
| 149 | { |
| 150 | return fp->len * sizeof(struct sock_filter) + sizeof(*fp); |
| 151 | } |
| 152 | |
Stephen Hemminger | 43db6d6 | 2008-04-10 01:43:09 -0700 | [diff] [blame] | 153 | extern int sk_filter(struct sock *sk, struct sk_buff *skb); |
Eric Dumazet | 62ab081 | 2010-12-06 20:50:09 +0000 | [diff] [blame] | 154 | extern unsigned int sk_run_filter(const struct sk_buff *skb, |
Eric Dumazet | 93aaae2 | 2010-11-19 09:49:59 -0800 | [diff] [blame] | 155 | const struct sock_filter *filter); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 156 | extern int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk); |
Pavel Emelyanov | 55b3332 | 2007-10-17 21:21:26 -0700 | [diff] [blame] | 157 | extern int sk_detach_filter(struct sock *sk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 158 | extern int sk_chk_filter(struct sock_filter *filter, int flen); |
Eric Dumazet | 0a14842 | 2011-04-20 09:27:32 +0000 | [diff] [blame] | 159 | |
| 160 | #ifdef CONFIG_BPF_JIT |
| 161 | extern void bpf_jit_compile(struct sk_filter *fp); |
| 162 | extern void bpf_jit_free(struct sk_filter *fp); |
| 163 | #define SK_RUN_FILTER(FILTER, SKB) (*FILTER->bpf_func)(SKB, FILTER->insns) |
| 164 | #else |
| 165 | static inline void bpf_jit_compile(struct sk_filter *fp) |
| 166 | { |
| 167 | } |
| 168 | static inline void bpf_jit_free(struct sk_filter *fp) |
| 169 | { |
| 170 | } |
| 171 | #define SK_RUN_FILTER(FILTER, SKB) sk_run_filter(SKB, FILTER->insns) |
| 172 | #endif |
| 173 | |
| 174 | enum { |
| 175 | BPF_S_RET_K = 1, |
| 176 | BPF_S_RET_A, |
| 177 | BPF_S_ALU_ADD_K, |
| 178 | BPF_S_ALU_ADD_X, |
| 179 | BPF_S_ALU_SUB_K, |
| 180 | BPF_S_ALU_SUB_X, |
| 181 | BPF_S_ALU_MUL_K, |
| 182 | BPF_S_ALU_MUL_X, |
| 183 | BPF_S_ALU_DIV_X, |
| 184 | BPF_S_ALU_AND_K, |
| 185 | BPF_S_ALU_AND_X, |
| 186 | BPF_S_ALU_OR_K, |
| 187 | BPF_S_ALU_OR_X, |
| 188 | BPF_S_ALU_LSH_K, |
| 189 | BPF_S_ALU_LSH_X, |
| 190 | BPF_S_ALU_RSH_K, |
| 191 | BPF_S_ALU_RSH_X, |
| 192 | BPF_S_ALU_NEG, |
| 193 | BPF_S_LD_W_ABS, |
| 194 | BPF_S_LD_H_ABS, |
| 195 | BPF_S_LD_B_ABS, |
| 196 | BPF_S_LD_W_LEN, |
| 197 | BPF_S_LD_W_IND, |
| 198 | BPF_S_LD_H_IND, |
| 199 | BPF_S_LD_B_IND, |
| 200 | BPF_S_LD_IMM, |
| 201 | BPF_S_LDX_W_LEN, |
| 202 | BPF_S_LDX_B_MSH, |
| 203 | BPF_S_LDX_IMM, |
| 204 | BPF_S_MISC_TAX, |
| 205 | BPF_S_MISC_TXA, |
| 206 | BPF_S_ALU_DIV_K, |
| 207 | BPF_S_LD_MEM, |
| 208 | BPF_S_LDX_MEM, |
| 209 | BPF_S_ST, |
| 210 | BPF_S_STX, |
| 211 | BPF_S_JMP_JA, |
| 212 | BPF_S_JMP_JEQ_K, |
| 213 | BPF_S_JMP_JEQ_X, |
| 214 | BPF_S_JMP_JGE_K, |
| 215 | BPF_S_JMP_JGE_X, |
| 216 | BPF_S_JMP_JGT_K, |
| 217 | BPF_S_JMP_JGT_X, |
| 218 | BPF_S_JMP_JSET_K, |
| 219 | BPF_S_JMP_JSET_X, |
| 220 | /* Ancillary data */ |
| 221 | BPF_S_ANC_PROTOCOL, |
| 222 | BPF_S_ANC_PKTTYPE, |
| 223 | BPF_S_ANC_IFINDEX, |
| 224 | BPF_S_ANC_NLATTR, |
| 225 | BPF_S_ANC_NLATTR_NEST, |
| 226 | BPF_S_ANC_MARK, |
| 227 | BPF_S_ANC_QUEUE, |
| 228 | BPF_S_ANC_HATYPE, |
| 229 | BPF_S_ANC_RXHASH, |
| 230 | BPF_S_ANC_CPU, |
| 231 | }; |
| 232 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 233 | #endif /* __KERNEL__ */ |
| 234 | |
| 235 | #endif /* __LINUX_FILTER_H__ */ |