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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /include/linux/filter.h
Initial import
Diffstat (limited to 'include/linux/filter.h')
-rw-r--r--include/linux/filter.h482
1 files changed, 482 insertions, 0 deletions
diff --git a/include/linux/filter.h b/include/linux/filter.h
new file mode 100644
index 000000000..fa11b3a36
--- /dev/null
+++ b/include/linux/filter.h
@@ -0,0 +1,482 @@
+/*
+ * 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 <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 })
+
+/* 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 })
+
+#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->prog->bpf_func)(ctx, filter->prog->insnsi)
+
+#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 */
+ bool jited; /* Is our filter JIT'ed? */
+ bool gpl_compatible; /* Is our filter GPL compatible? */
+ 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)
+
+static inline unsigned int bpf_prog_size(unsigned int proglen)
+{
+ return max(sizeof(struct bpf_prog),
+ offsetof(struct bpf_prog, insns[proglen]));
+}
+
+#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);
+
+void bpf_prog_select_runtime(struct bpf_prog *fp);
+void bpf_prog_free(struct bpf_prog *fp);
+
+int bpf_convert_filter(struct sock_filter *prog, int len,
+ struct bpf_insn *new_prog, int *new_len);
+
+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);
+}
+
+int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog);
+void bpf_prog_destroy(struct bpf_prog *fp);
+
+int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk);
+int sk_attach_bpf(u32 ufd, struct sock *sk);
+int sk_detach_filter(struct sock *sk);
+
+int bpf_check_classic(const struct sock_filter *filter, unsigned int flen);
+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);
+
+#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\n",
+ flen, proglen, pass, image);
+ 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 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__ */