diff options
Diffstat (limited to 'include/linux/filter.h')
| -rw-r--r-- | include/linux/filter.h | 384 |
1 files changed, 300 insertions, 84 deletions
diff --git a/include/linux/filter.h b/include/linux/filter.h index 024fd03e5d1..a7e3c48d73a 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -37,21 +37,270 @@ #define BPF_CALL 0x80 /* function call */ #define BPF_EXIT 0x90 /* function return */ +/* Register numbers */ +enum { + BPF_REG_0 = 0, + BPF_REG_1, + BPF_REG_2, + BPF_REG_3, + BPF_REG_4, + BPF_REG_5, + BPF_REG_6, + BPF_REG_7, + BPF_REG_8, + BPF_REG_9, + BPF_REG_10, + __MAX_BPF_REG, +}; + /* BPF has 10 general purpose 64-bit registers and stack frame. */ -#define MAX_BPF_REG 11 +#define MAX_BPF_REG __MAX_BPF_REG + +/* ArgX, context and stack frame pointer register positions. Note, + * Arg1, Arg2, Arg3, etc are used as argument mappings of function + * calls in BPF_CALL instruction. + */ +#define BPF_REG_ARG1 BPF_REG_1 +#define BPF_REG_ARG2 BPF_REG_2 +#define BPF_REG_ARG3 BPF_REG_3 +#define BPF_REG_ARG4 BPF_REG_4 +#define BPF_REG_ARG5 BPF_REG_5 +#define BPF_REG_CTX BPF_REG_6 +#define BPF_REG_FP BPF_REG_10 + +/* Additional register mappings for converted user programs. */ +#define BPF_REG_A BPF_REG_0 +#define BPF_REG_X BPF_REG_7 +#define BPF_REG_TMP BPF_REG_8 /* BPF program can access up to 512 bytes of stack space. */ #define MAX_BPF_STACK 512 -/* Arg1, context and stack frame pointer register positions. */ -#define ARG1_REG 1 -#define CTX_REG 6 -#define FP_REG 10 +/* Helper macros for filter block array initializers. */ + +/* ALU ops on registers, bpf_add|sub|...: dst_reg += src_reg */ + +#define BPF_ALU64_REG(OP, DST, SRC) \ + ((struct sock_filter_int) { \ + .code = BPF_ALU64 | BPF_OP(OP) | BPF_X, \ + .dst_reg = DST, \ + .src_reg = SRC, \ + .off = 0, \ + .imm = 0 }) + +#define BPF_ALU32_REG(OP, DST, SRC) \ + ((struct sock_filter_int) { \ + .code = BPF_ALU | BPF_OP(OP) | BPF_X, \ + .dst_reg = DST, \ + .src_reg = SRC, \ + .off = 0, \ + .imm = 0 }) + +/* ALU ops on immediates, bpf_add|sub|...: dst_reg += imm32 */ + +#define BPF_ALU64_IMM(OP, DST, IMM) \ + ((struct sock_filter_int) { \ + .code = BPF_ALU64 | BPF_OP(OP) | BPF_K, \ + .dst_reg = DST, \ + .src_reg = 0, \ + .off = 0, \ + .imm = IMM }) + +#define BPF_ALU32_IMM(OP, DST, IMM) \ + ((struct sock_filter_int) { \ + .code = BPF_ALU | BPF_OP(OP) | BPF_K, \ + .dst_reg = DST, \ + .src_reg = 0, \ + .off = 0, \ + .imm = IMM }) + +/* Endianess conversion, cpu_to_{l,b}e(), {l,b}e_to_cpu() */ + +#define BPF_ENDIAN(TYPE, DST, LEN) \ + ((struct sock_filter_int) { \ + .code = BPF_ALU | BPF_END | BPF_SRC(TYPE), \ + .dst_reg = DST, \ + .src_reg = 0, \ + .off = 0, \ + .imm = LEN }) + +/* Short form of mov, dst_reg = src_reg */ + +#define BPF_MOV64_REG(DST, SRC) \ + ((struct sock_filter_int) { \ + .code = BPF_ALU64 | BPF_MOV | BPF_X, \ + .dst_reg = DST, \ + .src_reg = SRC, \ + .off = 0, \ + .imm = 0 }) + +#define BPF_MOV32_REG(DST, SRC) \ + ((struct sock_filter_int) { \ + .code = BPF_ALU | BPF_MOV | BPF_X, \ + .dst_reg = DST, \ + .src_reg = SRC, \ + .off = 0, \ + .imm = 0 }) + +/* Short form of mov, dst_reg = imm32 */ + +#define BPF_MOV64_IMM(DST, IMM) \ + ((struct sock_filter_int) { \ + .code = BPF_ALU64 | BPF_MOV | BPF_K, \ + .dst_reg = DST, \ + .src_reg = 0, \ + .off = 0, \ + .imm = IMM }) + +#define BPF_MOV32_IMM(DST, IMM) \ + ((struct sock_filter_int) { \ + .code = BPF_ALU | BPF_MOV | BPF_K, \ + .dst_reg = DST, \ + .src_reg = 0, \ + .off = 0, \ + .imm = IMM }) + +/* Short form of mov based on type, BPF_X: dst_reg = src_reg, BPF_K: dst_reg = imm32 */ + +#define BPF_MOV64_RAW(TYPE, DST, SRC, IMM) \ + ((struct sock_filter_int) { \ + .code = BPF_ALU64 | BPF_MOV | BPF_SRC(TYPE), \ + .dst_reg = DST, \ + .src_reg = SRC, \ + .off = 0, \ + .imm = IMM }) + +#define BPF_MOV32_RAW(TYPE, DST, SRC, IMM) \ + ((struct sock_filter_int) { \ + .code = BPF_ALU | BPF_MOV | BPF_SRC(TYPE), \ + .dst_reg = DST, \ + .src_reg = SRC, \ + .off = 0, \ + .imm = IMM }) + +/* Direct packet access, R0 = *(uint *) (skb->data + imm32) */ + +#define BPF_LD_ABS(SIZE, IMM) \ + ((struct sock_filter_int) { \ + .code = BPF_LD | BPF_SIZE(SIZE) | BPF_ABS, \ + .dst_reg = 0, \ + .src_reg = 0, \ + .off = 0, \ + .imm = IMM }) + +/* Indirect packet access, R0 = *(uint *) (skb->data + src_reg + imm32) */ + +#define BPF_LD_IND(SIZE, SRC, IMM) \ + ((struct sock_filter_int) { \ + .code = BPF_LD | BPF_SIZE(SIZE) | BPF_IND, \ + .dst_reg = 0, \ + .src_reg = SRC, \ + .off = 0, \ + .imm = IMM }) + +/* Memory load, dst_reg = *(uint *) (src_reg + off16) */ + +#define BPF_LDX_MEM(SIZE, DST, SRC, OFF) \ + ((struct sock_filter_int) { \ + .code = BPF_LDX | BPF_SIZE(SIZE) | BPF_MEM, \ + .dst_reg = DST, \ + .src_reg = SRC, \ + .off = OFF, \ + .imm = 0 }) + +/* Memory store, *(uint *) (dst_reg + off16) = src_reg */ + +#define BPF_STX_MEM(SIZE, DST, SRC, OFF) \ + ((struct sock_filter_int) { \ + .code = BPF_STX | BPF_SIZE(SIZE) | BPF_MEM, \ + .dst_reg = DST, \ + .src_reg = SRC, \ + .off = OFF, \ + .imm = 0 }) + +/* Memory store, *(uint *) (dst_reg + off16) = imm32 */ + +#define BPF_ST_MEM(SIZE, DST, OFF, IMM) \ + ((struct sock_filter_int) { \ + .code = BPF_ST | BPF_SIZE(SIZE) | BPF_MEM, \ + .dst_reg = DST, \ + .src_reg = 0, \ + .off = OFF, \ + .imm = IMM }) + +/* Conditional jumps against registers, if (dst_reg 'op' src_reg) goto pc + off16 */ + +#define BPF_JMP_REG(OP, DST, SRC, OFF) \ + ((struct sock_filter_int) { \ + .code = BPF_JMP | BPF_OP(OP) | BPF_X, \ + .dst_reg = DST, \ + .src_reg = SRC, \ + .off = OFF, \ + .imm = 0 }) + +/* Conditional jumps against immediates, if (dst_reg 'op' imm32) goto pc + off16 */ + +#define BPF_JMP_IMM(OP, DST, IMM, OFF) \ + ((struct sock_filter_int) { \ + .code = BPF_JMP | BPF_OP(OP) | BPF_K, \ + .dst_reg = DST, \ + .src_reg = 0, \ + .off = OFF, \ + .imm = IMM }) + +/* Function call */ + +#define BPF_EMIT_CALL(FUNC) \ + ((struct sock_filter_int) { \ + .code = BPF_JMP | BPF_CALL, \ + .dst_reg = 0, \ + .src_reg = 0, \ + .off = 0, \ + .imm = ((FUNC) - __bpf_call_base) }) + +/* Raw code statement block */ + +#define BPF_RAW_INSN(CODE, DST, SRC, OFF, IMM) \ + ((struct sock_filter_int) { \ + .code = CODE, \ + .dst_reg = DST, \ + .src_reg = SRC, \ + .off = OFF, \ + .imm = IMM }) + +/* Program exit */ + +#define BPF_EXIT_INSN() \ + ((struct sock_filter_int) { \ + .code = BPF_JMP | BPF_EXIT, \ + .dst_reg = 0, \ + .src_reg = 0, \ + .off = 0, \ + .imm = 0 }) + +#define bytes_to_bpf_size(bytes) \ +({ \ + int bpf_size = -EINVAL; \ + \ + if (bytes == sizeof(u8)) \ + bpf_size = BPF_B; \ + else if (bytes == sizeof(u16)) \ + bpf_size = BPF_H; \ + else if (bytes == sizeof(u32)) \ + bpf_size = BPF_W; \ + else if (bytes == sizeof(u64)) \ + bpf_size = BPF_DW; \ + \ + bpf_size; \ +}) + +/* Macro to invoke filter function. */ +#define SK_RUN_FILTER(filter, ctx) (*filter->bpf_func)(ctx, filter->insnsi) struct sock_filter_int { __u8 code; /* opcode */ - __u8 a_reg:4; /* dest register */ - __u8 x_reg:4; /* source register */ + __u8 dst_reg:4; /* dest register */ + __u8 src_reg:4; /* source register */ __s16 off; /* signed offset */ __s32 imm; /* signed immediate constant */ }; @@ -97,21 +346,16 @@ static inline unsigned int sk_filter_size(unsigned int proglen) #define sk_filter_proglen(fprog) \ (fprog->len * sizeof(fprog->filter[0])) -#define SK_RUN_FILTER(filter, ctx) \ - (*filter->bpf_func)(ctx, filter->insnsi) - int sk_filter(struct sock *sk, struct sk_buff *skb); -u32 sk_run_filter_int_seccomp(const struct seccomp_data *ctx, - const struct sock_filter_int *insni); -u32 sk_run_filter_int_skb(const struct sk_buff *ctx, - const struct sock_filter_int *insni); +void sk_filter_select_runtime(struct sk_filter *fp); +void sk_filter_free(struct sk_filter *fp); int sk_convert_filter(struct sock_filter *prog, int len, struct sock_filter_int *new_prog, int *new_len); int sk_unattached_filter_create(struct sk_filter **pfp, - struct sock_fprog *fprog); + struct sock_fprog_kern *fprog); void sk_unattached_filter_destroy(struct sk_filter *fp); int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk); @@ -120,11 +364,48 @@ int sk_detach_filter(struct sock *sk); int sk_chk_filter(struct sock_filter *filter, unsigned int flen); int sk_get_filter(struct sock *sk, struct sock_filter __user *filter, unsigned int len); -void sk_decode_filter(struct sock_filter *filt, struct sock_filter *to); void sk_filter_charge(struct sock *sk, struct sk_filter *fp); void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp); +u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5); +void bpf_int_jit_compile(struct sk_filter *fp); + +#define BPF_ANC BIT(15) + +static inline u16 bpf_anc_helper(const struct sock_filter *ftest) +{ + BUG_ON(ftest->code & BPF_ANC); + + switch (ftest->code) { + case BPF_LD | BPF_W | BPF_ABS: + case BPF_LD | BPF_H | BPF_ABS: + case BPF_LD | BPF_B | BPF_ABS: +#define BPF_ANCILLARY(CODE) case SKF_AD_OFF + SKF_AD_##CODE: \ + return BPF_ANC | SKF_AD_##CODE + switch (ftest->k) { + BPF_ANCILLARY(PROTOCOL); + BPF_ANCILLARY(PKTTYPE); + BPF_ANCILLARY(IFINDEX); + BPF_ANCILLARY(NLATTR); + BPF_ANCILLARY(NLATTR_NEST); + BPF_ANCILLARY(MARK); + BPF_ANCILLARY(QUEUE); + BPF_ANCILLARY(HATYPE); + BPF_ANCILLARY(RXHASH); + BPF_ANCILLARY(CPU); + BPF_ANCILLARY(ALU_XOR_X); + BPF_ANCILLARY(VLAN_TAG); + BPF_ANCILLARY(VLAN_TAG_PRESENT); + BPF_ANCILLARY(PAY_OFFSET); + BPF_ANCILLARY(RANDOM); + } + /* Fallthrough. */ + default: + return ftest->code; + } +} + #ifdef CONFIG_BPF_JIT #include <stdarg.h> #include <linux/linkage.h> @@ -144,85 +425,20 @@ static inline void bpf_jit_dump(unsigned int flen, unsigned int proglen, } #else #include <linux/slab.h> + static inline void bpf_jit_compile(struct sk_filter *fp) { } + static inline void bpf_jit_free(struct sk_filter *fp) { kfree(fp); } -#endif +#endif /* CONFIG_BPF_JIT */ static inline int bpf_tell_extensions(void) { return SKF_AD_MAX; } -enum { - BPF_S_RET_K = 1, - BPF_S_RET_A, - BPF_S_ALU_ADD_K, - BPF_S_ALU_ADD_X, - BPF_S_ALU_SUB_K, - BPF_S_ALU_SUB_X, - BPF_S_ALU_MUL_K, - BPF_S_ALU_MUL_X, - BPF_S_ALU_DIV_X, - BPF_S_ALU_MOD_K, - BPF_S_ALU_MOD_X, - BPF_S_ALU_AND_K, - BPF_S_ALU_AND_X, - BPF_S_ALU_OR_K, - BPF_S_ALU_OR_X, - BPF_S_ALU_XOR_K, - BPF_S_ALU_XOR_X, - BPF_S_ALU_LSH_K, - BPF_S_ALU_LSH_X, - BPF_S_ALU_RSH_K, - BPF_S_ALU_RSH_X, - BPF_S_ALU_NEG, - BPF_S_LD_W_ABS, - BPF_S_LD_H_ABS, - BPF_S_LD_B_ABS, - BPF_S_LD_W_LEN, - BPF_S_LD_W_IND, - BPF_S_LD_H_IND, - BPF_S_LD_B_IND, - BPF_S_LD_IMM, - BPF_S_LDX_W_LEN, - BPF_S_LDX_B_MSH, - BPF_S_LDX_IMM, - BPF_S_MISC_TAX, - BPF_S_MISC_TXA, - BPF_S_ALU_DIV_K, - BPF_S_LD_MEM, - BPF_S_LDX_MEM, - BPF_S_ST, - BPF_S_STX, - BPF_S_JMP_JA, - BPF_S_JMP_JEQ_K, - BPF_S_JMP_JEQ_X, - BPF_S_JMP_JGE_K, - BPF_S_JMP_JGE_X, - BPF_S_JMP_JGT_K, - BPF_S_JMP_JGT_X, - BPF_S_JMP_JSET_K, - BPF_S_JMP_JSET_X, - /* Ancillary data */ - BPF_S_ANC_PROTOCOL, - BPF_S_ANC_PKTTYPE, - BPF_S_ANC_IFINDEX, - BPF_S_ANC_NLATTR, - BPF_S_ANC_NLATTR_NEST, - BPF_S_ANC_MARK, - BPF_S_ANC_QUEUE, - BPF_S_ANC_HATYPE, - BPF_S_ANC_RXHASH, - BPF_S_ANC_CPU, - BPF_S_ANC_ALU_XOR_X, - BPF_S_ANC_VLAN_TAG, - BPF_S_ANC_VLAN_TAG_PRESENT, - BPF_S_ANC_PAY_OFFSET, -}; - #endif /* __LINUX_FILTER_H__ */ |