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-rw-r--r--net/core/filter.c198
1 files changed, 99 insertions, 99 deletions
diff --git a/net/core/filter.c b/net/core/filter.c
index 6bd2e350e751..b3f21751b238 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -59,12 +59,12 @@
#define BPF_R10 regs[BPF_REG_10]
/* Named registers */
-#define A regs[insn->a_reg]
-#define X regs[insn->x_reg]
+#define DST regs[insn->dst_reg]
+#define SRC regs[insn->src_reg]
#define FP regs[BPF_REG_FP]
#define ARG1 regs[BPF_REG_ARG1]
#define CTX regs[BPF_REG_CTX]
-#define K insn->imm
+#define IMM insn->imm
/* No hurry in this branch
*
@@ -264,7 +264,7 @@ static unsigned int __sk_run_filter(void *ctx, const struct sock_filter_int *ins
FP = (u64) (unsigned long) &stack[ARRAY_SIZE(stack)];
ARG1 = (u64) (unsigned long) ctx;
- /* Register for user BPF programs need to be reset first. */
+ /* Registers used in classic BPF programs need to be reset first. */
regs[BPF_REG_A] = 0;
regs[BPF_REG_X] = 0;
@@ -274,16 +274,16 @@ select_insn:
/* ALU */
#define ALU(OPCODE, OP) \
ALU64_##OPCODE##_X: \
- A = A OP X; \
+ DST = DST OP SRC; \
CONT; \
ALU_##OPCODE##_X: \
- A = (u32) A OP (u32) X; \
+ DST = (u32) DST OP (u32) SRC; \
CONT; \
ALU64_##OPCODE##_K: \
- A = A OP K; \
+ DST = DST OP IMM; \
CONT; \
ALU_##OPCODE##_K: \
- A = (u32) A OP (u32) K; \
+ DST = (u32) DST OP (u32) IMM; \
CONT;
ALU(ADD, +)
@@ -296,92 +296,92 @@ select_insn:
ALU(MUL, *)
#undef ALU
ALU_NEG:
- A = (u32) -A;
+ DST = (u32) -DST;
CONT;
ALU64_NEG:
- A = -A;
+ DST = -DST;
CONT;
ALU_MOV_X:
- A = (u32) X;
+ DST = (u32) SRC;
CONT;
ALU_MOV_K:
- A = (u32) K;
+ DST = (u32) IMM;
CONT;
ALU64_MOV_X:
- A = X;
+ DST = SRC;
CONT;
ALU64_MOV_K:
- A = K;
+ DST = IMM;
CONT;
ALU64_ARSH_X:
- (*(s64 *) &A) >>= X;
+ (*(s64 *) &DST) >>= SRC;
CONT;
ALU64_ARSH_K:
- (*(s64 *) &A) >>= K;
+ (*(s64 *) &DST) >>= IMM;
CONT;
ALU64_MOD_X:
- if (unlikely(X == 0))
+ if (unlikely(SRC == 0))
return 0;
- tmp = A;
- A = do_div(tmp, X);
+ tmp = DST;
+ DST = do_div(tmp, SRC);
CONT;
ALU_MOD_X:
- if (unlikely(X == 0))
+ if (unlikely(SRC == 0))
return 0;
- tmp = (u32) A;
- A = do_div(tmp, (u32) X);
+ tmp = (u32) DST;
+ DST = do_div(tmp, (u32) SRC);
CONT;
ALU64_MOD_K:
- tmp = A;
- A = do_div(tmp, K);
+ tmp = DST;
+ DST = do_div(tmp, IMM);
CONT;
ALU_MOD_K:
- tmp = (u32) A;
- A = do_div(tmp, (u32) K);
+ tmp = (u32) DST;
+ DST = do_div(tmp, (u32) IMM);
CONT;
ALU64_DIV_X:
- if (unlikely(X == 0))
+ if (unlikely(SRC == 0))
return 0;
- do_div(A, X);
+ do_div(DST, SRC);
CONT;
ALU_DIV_X:
- if (unlikely(X == 0))
+ if (unlikely(SRC == 0))
return 0;
- tmp = (u32) A;
- do_div(tmp, (u32) X);
- A = (u32) tmp;
+ tmp = (u32) DST;
+ do_div(tmp, (u32) SRC);
+ DST = (u32) tmp;
CONT;
ALU64_DIV_K:
- do_div(A, K);
+ do_div(DST, IMM);
CONT;
ALU_DIV_K:
- tmp = (u32) A;
- do_div(tmp, (u32) K);
- A = (u32) tmp;
+ tmp = (u32) DST;
+ do_div(tmp, (u32) IMM);
+ DST = (u32) tmp;
CONT;
ALU_END_TO_BE:
- switch (K) {
+ switch (IMM) {
case 16:
- A = (__force u16) cpu_to_be16(A);
+ DST = (__force u16) cpu_to_be16(DST);
break;
case 32:
- A = (__force u32) cpu_to_be32(A);
+ DST = (__force u32) cpu_to_be32(DST);
break;
case 64:
- A = (__force u64) cpu_to_be64(A);
+ DST = (__force u64) cpu_to_be64(DST);
break;
}
CONT;
ALU_END_TO_LE:
- switch (K) {
+ switch (IMM) {
case 16:
- A = (__force u16) cpu_to_le16(A);
+ DST = (__force u16) cpu_to_le16(DST);
break;
case 32:
- A = (__force u32) cpu_to_le32(A);
+ DST = (__force u32) cpu_to_le32(DST);
break;
case 64:
- A = (__force u64) cpu_to_le64(A);
+ DST = (__force u64) cpu_to_le64(DST);
break;
}
CONT;
@@ -401,85 +401,85 @@ select_insn:
insn += insn->off;
CONT;
JMP_JEQ_X:
- if (A == X) {
+ if (DST == SRC) {
insn += insn->off;
CONT_JMP;
}
CONT;
JMP_JEQ_K:
- if (A == K) {
+ if (DST == IMM) {
insn += insn->off;
CONT_JMP;
}
CONT;
JMP_JNE_X:
- if (A != X) {
+ if (DST != SRC) {
insn += insn->off;
CONT_JMP;
}
CONT;
JMP_JNE_K:
- if (A != K) {
+ if (DST != IMM) {
insn += insn->off;
CONT_JMP;
}
CONT;
JMP_JGT_X:
- if (A > X) {
+ if (DST > SRC) {
insn += insn->off;
CONT_JMP;
}
CONT;
JMP_JGT_K:
- if (A > K) {
+ if (DST > IMM) {
insn += insn->off;
CONT_JMP;
}
CONT;
JMP_JGE_X:
- if (A >= X) {
+ if (DST >= SRC) {
insn += insn->off;
CONT_JMP;
}
CONT;
JMP_JGE_K:
- if (A >= K) {
+ if (DST >= IMM) {
insn += insn->off;
CONT_JMP;
}
CONT;
JMP_JSGT_X:
- if (((s64) A) > ((s64) X)) {
+ if (((s64) DST) > ((s64) SRC)) {
insn += insn->off;
CONT_JMP;
}
CONT;
JMP_JSGT_K:
- if (((s64) A) > ((s64) K)) {
+ if (((s64) DST) > ((s64) IMM)) {
insn += insn->off;
CONT_JMP;
}
CONT;
JMP_JSGE_X:
- if (((s64) A) >= ((s64) X)) {
+ if (((s64) DST) >= ((s64) SRC)) {
insn += insn->off;
CONT_JMP;
}
CONT;
JMP_JSGE_K:
- if (((s64) A) >= ((s64) K)) {
+ if (((s64) DST) >= ((s64) IMM)) {
insn += insn->off;
CONT_JMP;
}
CONT;
JMP_JSET_X:
- if (A & X) {
+ if (DST & SRC) {
insn += insn->off;
CONT_JMP;
}
CONT;
JMP_JSET_K:
- if (A & K) {
+ if (DST & IMM) {
insn += insn->off;
CONT_JMP;
}
@@ -488,15 +488,15 @@ select_insn:
return BPF_R0;
/* STX and ST and LDX*/
-#define LDST(SIZEOP, SIZE) \
- STX_MEM_##SIZEOP: \
- *(SIZE *)(unsigned long) (A + insn->off) = X; \
- CONT; \
- ST_MEM_##SIZEOP: \
- *(SIZE *)(unsigned long) (A + insn->off) = K; \
- CONT; \
- LDX_MEM_##SIZEOP: \
- A = *(SIZE *)(unsigned long) (X + insn->off); \
+#define LDST(SIZEOP, SIZE) \
+ STX_MEM_##SIZEOP: \
+ *(SIZE *)(unsigned long) (DST + insn->off) = SRC; \
+ CONT; \
+ ST_MEM_##SIZEOP: \
+ *(SIZE *)(unsigned long) (DST + insn->off) = IMM; \
+ CONT; \
+ LDX_MEM_##SIZEOP: \
+ DST = *(SIZE *)(unsigned long) (SRC + insn->off); \
CONT;
LDST(B, u8)
@@ -504,16 +504,16 @@ select_insn:
LDST(W, u32)
LDST(DW, u64)
#undef LDST
- STX_XADD_W: /* lock xadd *(u32 *)(A + insn->off) += X */
- atomic_add((u32) X, (atomic_t *)(unsigned long)
- (A + insn->off));
+ STX_XADD_W: /* lock xadd *(u32 *)(dst_reg + off16) += src_reg */
+ atomic_add((u32) SRC, (atomic_t *)(unsigned long)
+ (DST + insn->off));
CONT;
- STX_XADD_DW: /* lock xadd *(u64 *)(A + insn->off) += X */
- atomic64_add((u64) X, (atomic64_t *)(unsigned long)
- (A + insn->off));
+ STX_XADD_DW: /* lock xadd *(u64 *)(dst_reg + off16) += src_reg */
+ atomic64_add((u64) SRC, (atomic64_t *)(unsigned long)
+ (DST + insn->off));
CONT;
- LD_ABS_W: /* BPF_R0 = ntohl(*(u32 *) (skb->data + K)) */
- off = K;
+ LD_ABS_W: /* BPF_R0 = ntohl(*(u32 *) (skb->data + imm32)) */
+ off = IMM;
load_word:
/* BPF_LD + BPD_ABS and BPF_LD + BPF_IND insns are
* only appearing in the programs where ctx ==
@@ -527,51 +527,51 @@ load_word:
* BPF_R6-BPF_R9, and store return value into BPF_R0.
*
* Implicit input:
- * ctx
+ * ctx == skb == BPF_R6 == CTX
*
* Explicit input:
- * X == any register
- * K == 32-bit immediate
+ * SRC == any register
+ * IMM == 32-bit immediate
*
* Output:
* BPF_R0 - 8/16/32-bit skb data converted to cpu endianness
*/
- ptr = load_pointer((struct sk_buff *) ctx, off, 4, &tmp);
+ ptr = load_pointer((struct sk_buff *) CTX, off, 4, &tmp);
if (likely(ptr != NULL)) {
BPF_R0 = get_unaligned_be32(ptr);
CONT;
}
return 0;
- LD_ABS_H: /* BPF_R0 = ntohs(*(u16 *) (skb->data + K)) */
- off = K;
+ LD_ABS_H: /* BPF_R0 = ntohs(*(u16 *) (skb->data + imm32)) */
+ off = IMM;
load_half:
- ptr = load_pointer((struct sk_buff *) ctx, off, 2, &tmp);
+ ptr = load_pointer((struct sk_buff *) CTX, off, 2, &tmp);
if (likely(ptr != NULL)) {
BPF_R0 = get_unaligned_be16(ptr);
CONT;
}
return 0;
- LD_ABS_B: /* BPF_R0 = *(u8 *) (ctx + K) */
- off = K;
+ LD_ABS_B: /* BPF_R0 = *(u8 *) (skb->data + imm32) */
+ off = IMM;
load_byte:
- ptr = load_pointer((struct sk_buff *) ctx, off, 1, &tmp);
+ ptr = load_pointer((struct sk_buff *) CTX, off, 1, &tmp);
if (likely(ptr != NULL)) {
BPF_R0 = *(u8 *)ptr;
CONT;
}
return 0;
- LD_IND_W: /* BPF_R0 = ntohl(*(u32 *) (skb->data + X + K)) */
- off = K + X;
+ LD_IND_W: /* BPF_R0 = ntohl(*(u32 *) (skb->data + src_reg + imm32)) */
+ off = IMM + SRC;
goto load_word;
- LD_IND_H: /* BPF_R0 = ntohs(*(u16 *) (skb->data + X + K)) */
- off = K + X;
+ LD_IND_H: /* BPF_R0 = ntohs(*(u16 *) (skb->data + src_reg + imm32)) */
+ off = IMM + SRC;
goto load_half;
- LD_IND_B: /* BPF_R0 = *(u8 *) (skb->data + X + K) */
- off = K + X;
+ LD_IND_B: /* BPF_R0 = *(u8 *) (skb->data + src_reg + imm32) */
+ off = IMM + SRC;
goto load_byte;
default_label:
@@ -675,7 +675,7 @@ static bool convert_bpf_extensions(struct sock_filter *fp,
case SKF_AD_OFF + SKF_AD_PROTOCOL:
BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, protocol) != 2);
- /* A = *(u16 *) (ctx + offsetof(protocol)) */
+ /* A = *(u16 *) (CTX + offsetof(protocol)) */
*insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX,
offsetof(struct sk_buff, protocol));
/* A = ntohs(A) [emitting a nop or swap16] */
@@ -741,7 +741,7 @@ static bool convert_bpf_extensions(struct sock_filter *fp,
BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_tci) != 2);
BUILD_BUG_ON(VLAN_TAG_PRESENT != 0x1000);
- /* A = *(u16 *) (ctx + offsetof(vlan_tci)) */
+ /* A = *(u16 *) (CTX + offsetof(vlan_tci)) */
*insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX,
offsetof(struct sk_buff, vlan_tci));
if (fp->k == SKF_AD_OFF + SKF_AD_VLAN_TAG) {
@@ -760,13 +760,13 @@ static bool convert_bpf_extensions(struct sock_filter *fp,
case SKF_AD_OFF + SKF_AD_NLATTR_NEST:
case SKF_AD_OFF + SKF_AD_CPU:
case SKF_AD_OFF + SKF_AD_RANDOM:
- /* arg1 = ctx */
+ /* arg1 = CTX */
*insn++ = BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_CTX);
/* arg2 = A */
*insn++ = BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_A);
/* arg3 = X */
*insn++ = BPF_MOV64_REG(BPF_REG_ARG3, BPF_REG_X);
- /* Emit call(ctx, arg2=A, arg3=X) */
+ /* Emit call(arg1=CTX, arg2=A, arg3=X) */
switch (fp->k) {
case SKF_AD_OFF + SKF_AD_PAY_OFFSET:
*insn = BPF_EMIT_CALL(__skb_get_pay_offset);
@@ -941,12 +941,12 @@ do_pass:
*/
*insn++ = BPF_MOV32_IMM(BPF_REG_TMP, fp->k);
- insn->a_reg = BPF_REG_A;
- insn->x_reg = BPF_REG_TMP;
+ insn->dst_reg = BPF_REG_A;
+ insn->src_reg = BPF_REG_TMP;
bpf_src = BPF_X;
} else {
- insn->a_reg = BPF_REG_A;
- insn->x_reg = BPF_REG_X;
+ insn->dst_reg = BPF_REG_A;
+ insn->src_reg = BPF_REG_X;
insn->imm = fp->k;
bpf_src = BPF_SRC(fp->code);
}
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.