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 sock_fprog_kern {
  23         u16                     len;
  24         struct sock_filter      *filter;
  25 };
  26
  27 struct sk_buff;
  28 struct sock;
  29
  30 struct sk_filter {
  31         atomic_t                refcnt;
  32         u32                     jited:1,        /* Is our filter JIT'ed? */
  33                                 len:31;         /* Number of filter blocks */
  34         struct sock_fprog_kern  *orig_prog;     /* Original BPF program */
  35         struct rcu_head         rcu;
  36         unsigned int            (*bpf_func)(const struct sk_buff *skb,
  37                                             const struct sock_filter *filter);
  38         union {
  39                 struct sock_filter      insns[0];
  40                 struct work_struct      work;
  41         };
  42 };
  43
  44 static inline unsigned int sk_filter_size(unsigned int proglen)
  45 {
  46         return max(sizeof(struct sk_filter),
  47                    offsetof(struct sk_filter, insns[proglen]));
  48 }
  49
  50 #define sk_filter_proglen(fprog)                        \
  51                 (fprog->len * sizeof(fprog->filter[0]))
  52
  53 int sk_filter(struct sock *sk, struct sk_buff *skb);
  54 unsigned int sk_run_filter(const struct sk_buff *skb,
  55                            const struct sock_filter *filter);
  56
  57 int sk_unattached_filter_create(struct sk_filter **pfp,
  58                                 struct sock_fprog *fprog);
  59 void sk_unattached_filter_destroy(struct sk_filter *fp);
  60
  61 int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk);
  62 int sk_detach_filter(struct sock *sk);
  63
  64 int sk_chk_filter(struct sock_filter *filter, unsigned int flen);
  65 int sk_get_filter(struct sock *sk, struct sock_filter __user *filter,
  66                   unsigned int len);
  67 void sk_decode_filter(struct sock_filter *filt, struct sock_filter *to);
  68
  69 void sk_filter_charge(struct sock *sk, struct sk_filter *fp);
  70 void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp);
  71
  72 #ifdef CONFIG_BPF_JIT
  73 #include <stdarg.h>
  74 #include <linux/linkage.h>
  75 #include <linux/printk.h>
  76
  77 void bpf_jit_compile(struct sk_filter *fp);
  78 void bpf_jit_free(struct sk_filter *fp);
  79
  80 static inline void bpf_jit_dump(unsigned int flen, unsigned int proglen,
  81                                 u32 pass, void *image)
  82 {
  83         pr_err("flen=%u proglen=%u pass=%u image=%pK\n",
  84                flen, proglen, pass, image);
  85         if (image)
  86                 print_hex_dump(KERN_ERR, "JIT code: ", DUMP_PREFIX_OFFSET,
  87                                16, 1, image, proglen, false);
  88 }
  89 #define SK_RUN_FILTER(FILTER, SKB) (*FILTER->bpf_func)(SKB, FILTER->insns)
  90 #else
  91 #include <linux/slab.h>
  92 static inline void bpf_jit_compile(struct sk_filter *fp)
  93 {
  94 }
  95 static inline void bpf_jit_free(struct sk_filter *fp)
  96 {
  97         kfree(fp);
  98 }
  99 #define SK_RUN_FILTER(FILTER, SKB) sk_run_filter(SKB, FILTER->insns)
 100 #endif
 101
 102 static inline int bpf_tell_extensions(void)
 103 {
 104         return SKF_AD_MAX;
 105 }
 106
 107 enum {
 108         BPF_S_RET_K = 1,
 109         BPF_S_RET_A,
 110         BPF_S_ALU_ADD_K,
 111         BPF_S_ALU_ADD_X,
 112         BPF_S_ALU_SUB_K,
 113         BPF_S_ALU_SUB_X,
 114         BPF_S_ALU_MUL_K,
 115         BPF_S_ALU_MUL_X,
 116         BPF_S_ALU_DIV_X,
 117         BPF_S_ALU_MOD_K,
 118         BPF_S_ALU_MOD_X,
 119         BPF_S_ALU_AND_K,
 120         BPF_S_ALU_AND_X,
 121         BPF_S_ALU_OR_K,
 122         BPF_S_ALU_OR_X,
 123         BPF_S_ALU_XOR_K,
 124         BPF_S_ALU_XOR_X,
 125         BPF_S_ALU_LSH_K,
 126         BPF_S_ALU_LSH_X,
 127         BPF_S_ALU_RSH_K,
 128         BPF_S_ALU_RSH_X,
 129         BPF_S_ALU_NEG,
 130         BPF_S_LD_W_ABS,
 131         BPF_S_LD_H_ABS,
 132         BPF_S_LD_B_ABS,
 133         BPF_S_LD_W_LEN,
 134         BPF_S_LD_W_IND,
 135         BPF_S_LD_H_IND,
 136         BPF_S_LD_B_IND,
 137         BPF_S_LD_IMM,
 138         BPF_S_LDX_W_LEN,
 139         BPF_S_LDX_B_MSH,
 140         BPF_S_LDX_IMM,
 141         BPF_S_MISC_TAX,
 142         BPF_S_MISC_TXA,
 143         BPF_S_ALU_DIV_K,
 144         BPF_S_LD_MEM,
 145         BPF_S_LDX_MEM,
 146         BPF_S_ST,
 147         BPF_S_STX,
 148         BPF_S_JMP_JA,
 149         BPF_S_JMP_JEQ_K,
 150         BPF_S_JMP_JEQ_X,
 151         BPF_S_JMP_JGE_K,
 152         BPF_S_JMP_JGE_X,
 153         BPF_S_JMP_JGT_K,
 154         BPF_S_JMP_JGT_X,
 155         BPF_S_JMP_JSET_K,
 156         BPF_S_JMP_JSET_X,
 157         /* Ancillary data */
 158         BPF_S_ANC_PROTOCOL,
 159         BPF_S_ANC_PKTTYPE,
 160         BPF_S_ANC_IFINDEX,
 161         BPF_S_ANC_NLATTR,
 162         BPF_S_ANC_NLATTR_NEST,
 163         BPF_S_ANC_MARK,
 164         BPF_S_ANC_QUEUE,
 165         BPF_S_ANC_HATYPE,
 166         BPF_S_ANC_RXHASH,
 167         BPF_S_ANC_CPU,
 168         BPF_S_ANC_ALU_XOR_X,
 169         BPF_S_ANC_SECCOMP_LD_W,
 170         BPF_S_ANC_VLAN_TAG,
 171         BPF_S_ANC_VLAN_TAG_PRESENT,
 172         BPF_S_ANC_PAY_OFFSET,
 173 };
 174
 175 #endif /* __LINUX_FILTER_H__ */