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Diffstat (limited to 'include/linux/filter.h')
-rw-r--r--include/linux/filter.h255
1 files changed, 205 insertions, 50 deletions
diff --git a/include/linux/filter.h b/include/linux/filter.h
index 49ef7a298c92..f0c2ad43b4af 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -76,56 +76,211 @@ enum {
/* BPF program can access up to 512 bytes of stack space. */
#define MAX_BPF_STACK 512
-/* bpf_add|sub|...: a += x, bpf_mov: a = x */
-#define BPF_ALU64_REG(op, a, x) \
- ((struct sock_filter_int) {BPF_ALU64|BPF_OP(op)|BPF_X, a, x, 0, 0})
-#define BPF_ALU32_REG(op, a, x) \
- ((struct sock_filter_int) {BPF_ALU|BPF_OP(op)|BPF_X, a, x, 0, 0})
-
-/* bpf_add|sub|...: a += imm, bpf_mov: a = imm */
-#define BPF_ALU64_IMM(op, a, imm) \
- ((struct sock_filter_int) {BPF_ALU64|BPF_OP(op)|BPF_K, a, 0, 0, imm})
-#define BPF_ALU32_IMM(op, a, imm) \
- ((struct sock_filter_int) {BPF_ALU|BPF_OP(op)|BPF_K, a, 0, 0, imm})
-
-/* R0 = *(uint *) (skb->data + off) */
-#define BPF_LD_ABS(size, off) \
- ((struct sock_filter_int) {BPF_LD|BPF_SIZE(size)|BPF_ABS, 0, 0, 0, off})
-
-/* R0 = *(uint *) (skb->data + x + off) */
-#define BPF_LD_IND(size, x, off) \
- ((struct sock_filter_int) {BPF_LD|BPF_SIZE(size)|BPF_IND, 0, x, 0, off})
-
-/* a = *(uint *) (x + off) */
-#define BPF_LDX_MEM(sz, a, x, off) \
- ((struct sock_filter_int) {BPF_LDX|BPF_SIZE(sz)|BPF_MEM, a, x, off, 0})
-
-/* if (a 'op' x) goto pc+off */
-#define BPF_JMP_REG(op, a, x, off) \
- ((struct sock_filter_int) {BPF_JMP|BPF_OP(op)|BPF_X, a, x, off, 0})
-
-/* if (a 'op' imm) goto pc+off */
-#define BPF_JMP_IMM(op, a, imm, off) \
- ((struct sock_filter_int) {BPF_JMP|BPF_OP(op)|BPF_K, a, 0, off, imm})
-
-#define BPF_EXIT_INSN() \
- ((struct sock_filter_int) {BPF_JMP|BPF_EXIT, 0, 0, 0, 0})
-
-static inline int size_to_bpf(int size)
-{
- switch (size) {
- case 1:
- return BPF_B;
- case 2:
- return BPF_H;
- case 4:
- return BPF_W;
- case 8:
- return BPF_DW;
- default:
- return -EINVAL;
- }
-}
+/* Helper macros for filter block array initializers. */
+
+/* ALU ops on registers, bpf_add|sub|...: A += X */
+
+#define BPF_ALU64_REG(OP, A, X) \
+ ((struct sock_filter_int) { \
+ .code = BPF_ALU64 | BPF_OP(OP) | BPF_X, \
+ .a_reg = A, \
+ .x_reg = X, \
+ .off = 0, \
+ .imm = 0 })
+
+#define BPF_ALU32_REG(OP, A, X) \
+ ((struct sock_filter_int) { \
+ .code = BPF_ALU | BPF_OP(OP) | BPF_X, \
+ .a_reg = A, \
+ .x_reg = X, \
+ .off = 0, \
+ .imm = 0 })
+
+/* ALU ops on immediates, bpf_add|sub|...: A += IMM */
+
+#define BPF_ALU64_IMM(OP, A, IMM) \
+ ((struct sock_filter_int) { \
+ .code = BPF_ALU64 | BPF_OP(OP) | BPF_K, \
+ .a_reg = A, \
+ .x_reg = 0, \
+ .off = 0, \
+ .imm = IMM })
+
+#define BPF_ALU32_IMM(OP, A, IMM) \
+ ((struct sock_filter_int) { \
+ .code = BPF_ALU | BPF_OP(OP) | BPF_K, \
+ .a_reg = A, \
+ .x_reg = 0, \
+ .off = 0, \
+ .imm = IMM })
+
+/* Endianess conversion, cpu_to_{l,b}e(), {l,b}e_to_cpu() */
+
+#define BPF_ENDIAN(TYPE, A, LEN) \
+ ((struct sock_filter_int) { \
+ .code = BPF_ALU | BPF_END | BPF_SRC(TYPE), \
+ .a_reg = A, \
+ .x_reg = 0, \
+ .off = 0, \
+ .imm = LEN })
+
+/* Short form of mov, A = X */
+
+#define BPF_MOV64_REG(A, X) \
+ ((struct sock_filter_int) { \
+ .code = BPF_ALU64 | BPF_MOV | BPF_X, \
+ .a_reg = A, \
+ .x_reg = X, \
+ .off = 0, \
+ .imm = 0 })
+
+#define BPF_MOV32_REG(A, X) \
+ ((struct sock_filter_int) { \
+ .code = BPF_ALU | BPF_MOV | BPF_X, \
+ .a_reg = A, \
+ .x_reg = X, \
+ .off = 0, \
+ .imm = 0 })
+
+/* Short form of mov, A = IMM */
+
+#define BPF_MOV64_IMM(A, IMM) \
+ ((struct sock_filter_int) { \
+ .code = BPF_ALU64 | BPF_MOV | BPF_K, \
+ .a_reg = A, \
+ .x_reg = 0, \
+ .off = 0, \
+ .imm = IMM })
+
+#define BPF_MOV32_IMM(A, IMM) \
+ ((struct sock_filter_int) { \
+ .code = BPF_ALU | BPF_MOV | BPF_K, \
+ .a_reg = A, \
+ .x_reg = 0, \
+ .off = 0, \
+ .imm = IMM })
+
+/* Short form of mov based on type, BPF_X: A = X, BPF_K: A = IMM */
+
+#define BPF_MOV64_RAW(TYPE, A, X, IMM) \
+ ((struct sock_filter_int) { \
+ .code = BPF_ALU64 | BPF_MOV | BPF_SRC(TYPE), \
+ .a_reg = A, \
+ .x_reg = X, \
+ .off = 0, \
+ .imm = IMM })
+
+#define BPF_MOV32_RAW(TYPE, A, X, IMM) \
+ ((struct sock_filter_int) { \
+ .code = BPF_ALU | BPF_MOV | BPF_SRC(TYPE), \
+ .a_reg = A, \
+ .x_reg = X, \
+ .off = 0, \
+ .imm = IMM })
+
+/* Direct packet access, R0 = *(uint *) (skb->data + OFF) */
+
+#define BPF_LD_ABS(SIZE, OFF) \
+ ((struct sock_filter_int) { \
+ .code = BPF_LD | BPF_SIZE(SIZE) | BPF_ABS, \
+ .a_reg = 0, \
+ .x_reg = 0, \
+ .off = 0, \
+ .imm = OFF })
+
+/* Indirect packet access, R0 = *(uint *) (skb->data + X + OFF) */
+
+#define BPF_LD_IND(SIZE, X, OFF) \
+ ((struct sock_filter_int) { \
+ .code = BPF_LD | BPF_SIZE(SIZE) | BPF_IND, \
+ .a_reg = 0, \
+ .x_reg = X, \
+ .off = 0, \
+ .imm = OFF })
+
+/* Memory store, A = *(uint *) (X + OFF), and vice versa */
+
+#define BPF_LDX_MEM(SIZE, A, X, OFF) \
+ ((struct sock_filter_int) { \
+ .code = BPF_LDX | BPF_SIZE(SIZE) | BPF_MEM, \
+ .a_reg = A, \
+ .x_reg = X, \
+ .off = OFF, \
+ .imm = 0 })
+
+#define BPF_STX_MEM(SIZE, A, X, OFF) \
+ ((struct sock_filter_int) { \
+ .code = BPF_STX | BPF_SIZE(SIZE) | BPF_MEM, \
+ .a_reg = A, \
+ .x_reg = X, \
+ .off = OFF, \
+ .imm = 0 })
+
+/* Conditional jumps against registers, if (A 'op' X) goto pc + OFF */
+
+#define BPF_JMP_REG(OP, A, X, OFF) \
+ ((struct sock_filter_int) { \
+ .code = BPF_JMP | BPF_OP(OP) | BPF_X, \
+ .a_reg = A, \
+ .x_reg = X, \
+ .off = OFF, \
+ .imm = 0 })
+
+/* Conditional jumps against immediates, if (A 'op' IMM) goto pc + OFF */
+
+#define BPF_JMP_IMM(OP, A, IMM, OFF) \
+ ((struct sock_filter_int) { \
+ .code = BPF_JMP | BPF_OP(OP) | BPF_K, \
+ .a_reg = A, \
+ .x_reg = 0, \
+ .off = OFF, \
+ .imm = IMM })
+
+/* Function call */
+
+#define BPF_EMIT_CALL(FUNC) \
+ ((struct sock_filter_int) { \
+ .code = BPF_JMP | BPF_CALL, \
+ .a_reg = 0, \
+ .x_reg = 0, \
+ .off = 0, \
+ .imm = ((FUNC) - __bpf_call_base) })
+
+/* Raw code statement block */
+
+#define BPF_RAW_INSN(CODE, A, X, OFF, IMM) \
+ ((struct sock_filter_int) { \
+ .code = CODE, \
+ .a_reg = A, \
+ .x_reg = X, \
+ .off = OFF, \
+ .imm = IMM })
+
+/* Program exit */
+
+#define BPF_EXIT_INSN() \
+ ((struct sock_filter_int) { \
+ .code = BPF_JMP | BPF_EXIT, \
+ .a_reg = 0, \
+ .x_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)
generated by cgit v1.2.3 (git 2.0.4) at 2024-09-14 00:11:46 +0000