include/linux/filter.h

   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 static inline int bpf_tell_extensions(void)
  87 {
  88         return SKF_AD_MAX;
  89 }
  90
  91 enum {
  92         BPF_S_RET_K = 1,
  93         BPF_S_RET_A,
  94         BPF_S_ALU_ADD_K,
  95         BPF_S_ALU_ADD_X,
  96         BPF_S_ALU_SUB_K,
  97         BPF_S_ALU_SUB_X,
  98         BPF_S_ALU_MUL_K,
  99         BPF_S_ALU_MUL_X,
 100         BPF_S_ALU_DIV_X,
 101         BPF_S_ALU_MOD_K,
 102         BPF_S_ALU_MOD_X,
 103         BPF_S_ALU_AND_K,
 104         BPF_S_ALU_AND_X,
 105         BPF_S_ALU_OR_K,
 106         BPF_S_ALU_OR_X,
 107         BPF_S_ALU_XOR_K,
 108         BPF_S_ALU_XOR_X,
 109         BPF_S_ALU_LSH_K,
 110         BPF_S_ALU_LSH_X,
 111         BPF_S_ALU_RSH_K,
 112         BPF_S_ALU_RSH_X,
 113         BPF_S_ALU_NEG,
 114         BPF_S_LD_W_ABS,
 115         BPF_S_LD_H_ABS,
 116         BPF_S_LD_B_ABS,
 117         BPF_S_LD_W_LEN,
 118         BPF_S_LD_W_IND,
 119         BPF_S_LD_H_IND,
 120         BPF_S_LD_B_IND,
 121         BPF_S_LD_IMM,
 122         BPF_S_LDX_W_LEN,
 123         BPF_S_LDX_B_MSH,
 124         BPF_S_LDX_IMM,
 125         BPF_S_MISC_TAX,
 126         BPF_S_MISC_TXA,
 127         BPF_S_ALU_DIV_K,
 128         BPF_S_LD_MEM,
 129         BPF_S_LDX_MEM,
 130         BPF_S_ST,
 131         BPF_S_STX,
 132         BPF_S_JMP_JA,
 133         BPF_S_JMP_JEQ_K,
 134         BPF_S_JMP_JEQ_X,
 135         BPF_S_JMP_JGE_K,
 136         BPF_S_JMP_JGE_X,
 137         BPF_S_JMP_JGT_K,
 138         BPF_S_JMP_JGT_X,
 139         BPF_S_JMP_JSET_K,
 140         BPF_S_JMP_JSET_X,
 141         /* Ancillary data */
 142         BPF_S_ANC_PROTOCOL,
 143         BPF_S_ANC_PKTTYPE,
 144         BPF_S_ANC_IFINDEX,
 145         BPF_S_ANC_NLATTR,
 146         BPF_S_ANC_NLATTR_NEST,
 147         BPF_S_ANC_MARK,
 148         BPF_S_ANC_QUEUE,
 149         BPF_S_ANC_HATYPE,
 150         BPF_S_ANC_RXHASH,
 151         BPF_S_ANC_CPU,
 152         BPF_S_ANC_ALU_XOR_X,
 153         BPF_S_ANC_SECCOMP_LD_W,
 154         BPF_S_ANC_VLAN_TAG,
 155         BPF_S_ANC_VLAN_TAG_PRESENT,
 156         BPF_S_ANC_PAY_OFFSET,
 157 };
 158
 159 #endif /* __LINUX_FILTER_H__ */