| /* |
| * Linux Socket Filter Data Structures |
| */ |
| #ifndef __LINUX_FILTER_H__ |
| #define __LINUX_FILTER_H__ |
| |
| #include <stdarg.h> |
| |
| #include <linux/atomic.h> |
| #include <linux/compat.h> |
| #include <linux/skbuff.h> |
| #include <linux/linkage.h> |
| #include <linux/printk.h> |
| #include <linux/workqueue.h> |
| #include <linux/sched.h> |
| #include <net/sch_generic.h> |
| |
| #include <asm/cacheflush.h> |
| |
| #include <uapi/linux/filter.h> |
| #include <uapi/linux/bpf.h> |
| |
| struct sk_buff; |
| struct sock; |
| struct seccomp_data; |
| struct bpf_prog_aux; |
| |
| /* 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 |
| |
| /* 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 bpf_insn) { \ |
| .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 bpf_insn) { \ |
| .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 bpf_insn) { \ |
| .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 bpf_insn) { \ |
| .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 bpf_insn) { \ |
| .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 bpf_insn) { \ |
| .code = BPF_ALU64 | BPF_MOV | BPF_X, \ |
| .dst_reg = DST, \ |
| .src_reg = SRC, \ |
| .off = 0, \ |
| .imm = 0 }) |
| |
| #define BPF_MOV32_REG(DST, SRC) \ |
| ((struct bpf_insn) { \ |
| .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 bpf_insn) { \ |
| .code = BPF_ALU64 | BPF_MOV | BPF_K, \ |
| .dst_reg = DST, \ |
| .src_reg = 0, \ |
| .off = 0, \ |
| .imm = IMM }) |
| |
| #define BPF_MOV32_IMM(DST, IMM) \ |
| ((struct bpf_insn) { \ |
| .code = BPF_ALU | BPF_MOV | BPF_K, \ |
| .dst_reg = DST, \ |
| .src_reg = 0, \ |
| .off = 0, \ |
| .imm = IMM }) |
| |
| /* BPF_LD_IMM64 macro encodes single 'load 64-bit immediate' insn */ |
| #define BPF_LD_IMM64(DST, IMM) \ |
| BPF_LD_IMM64_RAW(DST, 0, IMM) |
| |
| #define BPF_LD_IMM64_RAW(DST, SRC, IMM) \ |
| ((struct bpf_insn) { \ |
| .code = BPF_LD | BPF_DW | BPF_IMM, \ |
| .dst_reg = DST, \ |
| .src_reg = SRC, \ |
| .off = 0, \ |
| .imm = (__u32) (IMM) }), \ |
| ((struct bpf_insn) { \ |
| .code = 0, /* zero is reserved opcode */ \ |
| .dst_reg = 0, \ |
| .src_reg = 0, \ |
| .off = 0, \ |
| .imm = ((__u64) (IMM)) >> 32 }) |
| |
| /* pseudo BPF_LD_IMM64 insn used to refer to process-local map_fd */ |
| #define BPF_LD_MAP_FD(DST, MAP_FD) \ |
| BPF_LD_IMM64_RAW(DST, BPF_PSEUDO_MAP_FD, MAP_FD) |
| |
| /* 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 bpf_insn) { \ |
| .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 bpf_insn) { \ |
| .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 bpf_insn) { \ |
| .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 bpf_insn) { \ |
| .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 bpf_insn) { \ |
| .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 bpf_insn) { \ |
| .code = BPF_STX | BPF_SIZE(SIZE) | BPF_MEM, \ |
| .dst_reg = DST, \ |
| .src_reg = SRC, \ |
| .off = OFF, \ |
| .imm = 0 }) |
| |
| /* Atomic memory add, *(uint *)(dst_reg + off16) += src_reg */ |
| |
| #define BPF_STX_XADD(SIZE, DST, SRC, OFF) \ |
| ((struct bpf_insn) { \ |
| .code = BPF_STX | BPF_SIZE(SIZE) | BPF_XADD, \ |
| .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 bpf_insn) { \ |
| .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 bpf_insn) { \ |
| .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 bpf_insn) { \ |
| .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 bpf_insn) { \ |
| .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 bpf_insn) { \ |
| .code = CODE, \ |
| .dst_reg = DST, \ |
| .src_reg = SRC, \ |
| .off = OFF, \ |
| .imm = IMM }) |
| |
| /* Program exit */ |
| |
| #define BPF_EXIT_INSN() \ |
| ((struct bpf_insn) { \ |
| .code = BPF_JMP | BPF_EXIT, \ |
| .dst_reg = 0, \ |
| .src_reg = 0, \ |
| .off = 0, \ |
| .imm = 0 }) |
| |
| /* Internal classic blocks for direct assignment */ |
| |
| #define __BPF_STMT(CODE, K) \ |
| ((struct sock_filter) BPF_STMT(CODE, K)) |
| |
| #define __BPF_JUMP(CODE, K, JT, JF) \ |
| ((struct sock_filter) BPF_JUMP(CODE, K, JT, JF)) |
| |
| #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; \ |
| }) |
| |
| #ifdef CONFIG_COMPAT |
| /* A struct sock_filter is architecture independent. */ |
| struct compat_sock_fprog { |
| u16 len; |
| compat_uptr_t filter; /* struct sock_filter * */ |
| }; |
| #endif |
| |
| struct sock_fprog_kern { |
| u16 len; |
| struct sock_filter *filter; |
| }; |
| |
| struct bpf_binary_header { |
| unsigned int pages; |
| u8 image[]; |
| }; |
| |
| struct bpf_prog { |
| u16 pages; /* Number of allocated pages */ |
| kmemcheck_bitfield_begin(meta); |
| u16 jited:1, /* Is our filter JIT'ed? */ |
| gpl_compatible:1, /* Is filter GPL compatible? */ |
| cb_access:1, /* Is control block accessed? */ |
| dst_needed:1; /* Do we need dst entry? */ |
| kmemcheck_bitfield_end(meta); |
| u32 len; /* Number of filter blocks */ |
| enum bpf_prog_type type; /* Type of BPF program */ |
| struct bpf_prog_aux *aux; /* Auxiliary fields */ |
| struct sock_fprog_kern *orig_prog; /* Original BPF program */ |
| unsigned int (*bpf_func)(const struct sk_buff *skb, |
| const struct bpf_insn *filter); |
| /* Instructions for interpreter */ |
| union { |
| struct sock_filter insns[0]; |
| struct bpf_insn insnsi[0]; |
| }; |
| }; |
| |
| struct sk_filter { |
| atomic_t refcnt; |
| struct rcu_head rcu; |
| struct bpf_prog *prog; |
| }; |
| |
| #define BPF_PROG_RUN(filter, ctx) (*filter->bpf_func)(ctx, filter->insnsi) |
| |
| #define BPF_SKB_CB_LEN QDISC_CB_PRIV_LEN |
| |
| static inline u8 *bpf_skb_cb(struct sk_buff *skb) |
| { |
| /* eBPF programs may read/write skb->cb[] area to transfer meta |
| * data between tail calls. Since this also needs to work with |
| * tc, that scratch memory is mapped to qdisc_skb_cb's data area. |
| * |
| * In some socket filter cases, the cb unfortunately needs to be |
| * saved/restored so that protocol specific skb->cb[] data won't |
| * be lost. In any case, due to unpriviledged eBPF programs |
| * attached to sockets, we need to clear the bpf_skb_cb() area |
| * to not leak previous contents to user space. |
| */ |
| BUILD_BUG_ON(FIELD_SIZEOF(struct __sk_buff, cb) != BPF_SKB_CB_LEN); |
| BUILD_BUG_ON(FIELD_SIZEOF(struct __sk_buff, cb) != |
| FIELD_SIZEOF(struct qdisc_skb_cb, data)); |
| |
| return qdisc_skb_cb(skb)->data; |
| } |
| |
| static inline u32 bpf_prog_run_save_cb(const struct bpf_prog *prog, |
| struct sk_buff *skb) |
| { |
| u8 *cb_data = bpf_skb_cb(skb); |
| u8 cb_saved[BPF_SKB_CB_LEN]; |
| u32 res; |
| |
| if (unlikely(prog->cb_access)) { |
| memcpy(cb_saved, cb_data, sizeof(cb_saved)); |
| memset(cb_data, 0, sizeof(cb_saved)); |
| } |
| |
| res = BPF_PROG_RUN(prog, skb); |
| |
| if (unlikely(prog->cb_access)) |
| memcpy(cb_data, cb_saved, sizeof(cb_saved)); |
| |
| return res; |
| } |
| |
| static inline u32 bpf_prog_run_clear_cb(const struct bpf_prog *prog, |
| struct sk_buff *skb) |
| { |
| u8 *cb_data = bpf_skb_cb(skb); |
| |
| if (unlikely(prog->cb_access)) |
| memset(cb_data, 0, BPF_SKB_CB_LEN); |
| |
| return BPF_PROG_RUN(prog, skb); |
| } |
| |
| static inline unsigned int bpf_prog_size(unsigned int proglen) |
| { |
| return max(sizeof(struct bpf_prog), |
| offsetof(struct bpf_prog, insns[proglen])); |
| } |
| |
| static inline bool bpf_prog_was_classic(const struct bpf_prog *prog) |
| { |
| /* When classic BPF programs have been loaded and the arch |
| * does not have a classic BPF JIT (anymore), they have been |
| * converted via bpf_migrate_filter() to eBPF and thus always |
| * have an unspec program type. |
| */ |
| return prog->type == BPF_PROG_TYPE_UNSPEC; |
| } |
| |
| #define bpf_classic_proglen(fprog) (fprog->len * sizeof(fprog->filter[0])) |
| |
| #ifdef CONFIG_DEBUG_SET_MODULE_RONX |
| static inline void bpf_prog_lock_ro(struct bpf_prog *fp) |
| { |
| set_memory_ro((unsigned long)fp, fp->pages); |
| } |
| |
| static inline void bpf_prog_unlock_ro(struct bpf_prog *fp) |
| { |
| set_memory_rw((unsigned long)fp, fp->pages); |
| } |
| #else |
| static inline void bpf_prog_lock_ro(struct bpf_prog *fp) |
| { |
| } |
| |
| static inline void bpf_prog_unlock_ro(struct bpf_prog *fp) |
| { |
| } |
| #endif /* CONFIG_DEBUG_SET_MODULE_RONX */ |
| |
| int sk_filter(struct sock *sk, struct sk_buff *skb); |
| |
| int bpf_prog_select_runtime(struct bpf_prog *fp); |
| void bpf_prog_free(struct bpf_prog *fp); |
| |
| struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags); |
| struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size, |
| gfp_t gfp_extra_flags); |
| void __bpf_prog_free(struct bpf_prog *fp); |
| |
| static inline void bpf_prog_unlock_free(struct bpf_prog *fp) |
| { |
| bpf_prog_unlock_ro(fp); |
| __bpf_prog_free(fp); |
| } |
| |
| typedef int (*bpf_aux_classic_check_t)(struct sock_filter *filter, |
| unsigned int flen); |
| |
| int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog); |
| int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog, |
| bpf_aux_classic_check_t trans, bool save_orig); |
| void bpf_prog_destroy(struct bpf_prog *fp); |
| |
| int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk); |
| int __sk_attach_filter(struct sock_fprog *fprog, struct sock *sk, |
| bool locked); |
| int sk_attach_bpf(u32 ufd, struct sock *sk); |
| int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk); |
| int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk); |
| int sk_detach_filter(struct sock *sk); |
| int __sk_detach_filter(struct sock *sk, bool locked); |
| |
| int sk_get_filter(struct sock *sk, struct sock_filter __user *filter, |
| unsigned int len); |
| |
| bool 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 bpf_prog *fp); |
| bool bpf_helper_changes_skb_data(void *func); |
| |
| #ifdef CONFIG_BPF_JIT |
| typedef void (*bpf_jit_fill_hole_t)(void *area, unsigned int size); |
| |
| struct bpf_binary_header * |
| bpf_jit_binary_alloc(unsigned int proglen, u8 **image_ptr, |
| unsigned int alignment, |
| bpf_jit_fill_hole_t bpf_fill_ill_insns); |
| void bpf_jit_binary_free(struct bpf_binary_header *hdr); |
| |
| void bpf_jit_compile(struct bpf_prog *fp); |
| void bpf_jit_free(struct bpf_prog *fp); |
| |
| static inline void bpf_jit_dump(unsigned int flen, unsigned int proglen, |
| u32 pass, void *image) |
| { |
| pr_err("flen=%u proglen=%u pass=%u image=%pK from=%s pid=%d\n", flen, |
| proglen, pass, image, current->comm, task_pid_nr(current)); |
| |
| if (image) |
| print_hex_dump(KERN_ERR, "JIT code: ", DUMP_PREFIX_OFFSET, |
| 16, 1, image, proglen, false); |
| } |
| #else |
| static inline void bpf_jit_compile(struct bpf_prog *fp) |
| { |
| } |
| |
| static inline void bpf_jit_free(struct bpf_prog *fp) |
| { |
| bpf_prog_unlock_free(fp); |
| } |
| #endif /* CONFIG_BPF_JIT */ |
| |
| #define BPF_ANC BIT(15) |
| |
| static inline bool bpf_needs_clear_a(const struct sock_filter *first) |
| { |
| switch (first->code) { |
| case BPF_RET | BPF_K: |
| case BPF_LD | BPF_W | BPF_LEN: |
| return false; |
| |
| case BPF_LD | BPF_W | BPF_ABS: |
| case BPF_LD | BPF_H | BPF_ABS: |
| case BPF_LD | BPF_B | BPF_ABS: |
| if (first->k == SKF_AD_OFF + SKF_AD_ALU_XOR_X) |
| return true; |
| return false; |
| |
| default: |
| return true; |
| } |
| } |
| |
| 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); |
| BPF_ANCILLARY(VLAN_TPID); |
| } |
| /* Fallthrough. */ |
| default: |
| return ftest->code; |
| } |
| } |
| |
| void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb, |
| int k, unsigned int size); |
| |
| static inline void *bpf_load_pointer(const struct sk_buff *skb, int k, |
| unsigned int size, void *buffer) |
| { |
| if (k >= 0) |
| return skb_header_pointer(skb, k, size, buffer); |
| |
| return bpf_internal_load_pointer_neg_helper(skb, k, size); |
| } |
| |
| static inline int bpf_tell_extensions(void) |
| { |
| return SKF_AD_MAX; |
| } |
| |
| #endif /* __LINUX_FILTER_H__ */ |