[PATCH RFC v2 net-next 01/16] net: filter: split filter.c into two files
From: Alexei Starovoitov
Date: Fri Jul 18 2014 - 00:36:45 EST
BPF is used in several kernel components. This split creates logical boundary
between generic eBPF core and the rest
kernel/bpf/core.c: eBPF interpreter
net/core/filter.c: classic->eBPF converter, classic verifiers, socket filters
This patch only moves functions.
Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxxxx>
---
kernel/Makefile | 1 +
kernel/bpf/Makefile | 1 +
kernel/bpf/core.c | 536 +++++++++++++++++++++++++++++++++++++++++++++++++++
net/core/filter.c | 511 ------------------------------------------------
4 files changed, 538 insertions(+), 511 deletions(-)
create mode 100644 kernel/bpf/Makefile
create mode 100644 kernel/bpf/core.c
diff --git a/kernel/Makefile b/kernel/Makefile
index f2a8b6246ce9..e7360b7c2c0e 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -87,6 +87,7 @@ obj-$(CONFIG_RING_BUFFER) += trace/
obj-$(CONFIG_TRACEPOINTS) += trace/
obj-$(CONFIG_IRQ_WORK) += irq_work.o
obj-$(CONFIG_CPU_PM) += cpu_pm.o
+obj-$(CONFIG_NET) += bpf/
obj-$(CONFIG_PERF_EVENTS) += events/
diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile
new file mode 100644
index 000000000000..6a71145e2769
--- /dev/null
+++ b/kernel/bpf/Makefile
@@ -0,0 +1 @@
+obj-y := core.o
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
new file mode 100644
index 000000000000..77a240a1ce11
--- /dev/null
+++ b/kernel/bpf/core.c
@@ -0,0 +1,536 @@
+/*
+ * Linux Socket Filter - Kernel level socket filtering
+ *
+ * Based on the design of the Berkeley Packet Filter. The new
+ * internal format has been designed by PLUMgrid:
+ *
+ * Copyright (c) 2011 - 2014 PLUMgrid, http://plumgrid.com
+ *
+ * Authors:
+ *
+ * Jay Schulist <jschlst@xxxxxxxxx>
+ * Alexei Starovoitov <ast@xxxxxxxxxxxx>
+ * Daniel Borkmann <dborkman@xxxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * Andi Kleen - Fix a few bad bugs and races.
+ * Kris Katterjohn - Added many additional checks in sk_chk_filter()
+ */
+#include <linux/filter.h>
+#include <linux/skbuff.h>
+#include <asm/unaligned.h>
+
+/* Registers */
+#define BPF_R0 regs[BPF_REG_0]
+#define BPF_R1 regs[BPF_REG_1]
+#define BPF_R2 regs[BPF_REG_2]
+#define BPF_R3 regs[BPF_REG_3]
+#define BPF_R4 regs[BPF_REG_4]
+#define BPF_R5 regs[BPF_REG_5]
+#define BPF_R6 regs[BPF_REG_6]
+#define BPF_R7 regs[BPF_REG_7]
+#define BPF_R8 regs[BPF_REG_8]
+#define BPF_R9 regs[BPF_REG_9]
+#define BPF_R10 regs[BPF_REG_10]
+
+/* Named registers */
+#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 IMM insn->imm
+
+/* No hurry in this branch
+ *
+ * Exported for the bpf jit load helper.
+ */
+void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb, int k, unsigned int size)
+{
+ u8 *ptr = NULL;
+
+ if (k >= SKF_NET_OFF)
+ ptr = skb_network_header(skb) + k - SKF_NET_OFF;
+ else if (k >= SKF_LL_OFF)
+ ptr = skb_mac_header(skb) + k - SKF_LL_OFF;
+ if (ptr >= skb->head && ptr + size <= skb_tail_pointer(skb))
+ return ptr;
+
+ return NULL;
+}
+
+/* Base function for offset calculation. Needs to go into .text section,
+ * therefore keeping it non-static as well; will also be used by JITs
+ * anyway later on, so do not let the compiler omit it.
+ */
+noinline u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
+{
+ return 0;
+}
+
+/**
+ * __sk_run_filter - run a filter on a given context
+ * @ctx: buffer to run the filter on
+ * @insn: filter to apply
+ *
+ * Decode and apply filter instructions to the skb->data. Return length to
+ * keep, 0 for none. @ctx is the data we are operating on, @insn is the
+ * array of filter instructions.
+ */
+static unsigned int __sk_run_filter(void *ctx, const struct sock_filter_int *insn)
+{
+ u64 stack[MAX_BPF_STACK / sizeof(u64)];
+ u64 regs[MAX_BPF_REG], tmp;
+ static const void *jumptable[256] = {
+ [0 ... 255] = &&default_label,
+ /* Now overwrite non-defaults ... */
+ /* 32 bit ALU operations */
+ [BPF_ALU | BPF_ADD | BPF_X] = &&ALU_ADD_X,
+ [BPF_ALU | BPF_ADD | BPF_K] = &&ALU_ADD_K,
+ [BPF_ALU | BPF_SUB | BPF_X] = &&ALU_SUB_X,
+ [BPF_ALU | BPF_SUB | BPF_K] = &&ALU_SUB_K,
+ [BPF_ALU | BPF_AND | BPF_X] = &&ALU_AND_X,
+ [BPF_ALU | BPF_AND | BPF_K] = &&ALU_AND_K,
+ [BPF_ALU | BPF_OR | BPF_X] = &&ALU_OR_X,
+ [BPF_ALU | BPF_OR | BPF_K] = &&ALU_OR_K,
+ [BPF_ALU | BPF_LSH | BPF_X] = &&ALU_LSH_X,
+ [BPF_ALU | BPF_LSH | BPF_K] = &&ALU_LSH_K,
+ [BPF_ALU | BPF_RSH | BPF_X] = &&ALU_RSH_X,
+ [BPF_ALU | BPF_RSH | BPF_K] = &&ALU_RSH_K,
+ [BPF_ALU | BPF_XOR | BPF_X] = &&ALU_XOR_X,
+ [BPF_ALU | BPF_XOR | BPF_K] = &&ALU_XOR_K,
+ [BPF_ALU | BPF_MUL | BPF_X] = &&ALU_MUL_X,
+ [BPF_ALU | BPF_MUL | BPF_K] = &&ALU_MUL_K,
+ [BPF_ALU | BPF_MOV | BPF_X] = &&ALU_MOV_X,
+ [BPF_ALU | BPF_MOV | BPF_K] = &&ALU_MOV_K,
+ [BPF_ALU | BPF_DIV | BPF_X] = &&ALU_DIV_X,
+ [BPF_ALU | BPF_DIV | BPF_K] = &&ALU_DIV_K,
+ [BPF_ALU | BPF_MOD | BPF_X] = &&ALU_MOD_X,
+ [BPF_ALU | BPF_MOD | BPF_K] = &&ALU_MOD_K,
+ [BPF_ALU | BPF_NEG] = &&ALU_NEG,
+ [BPF_ALU | BPF_END | BPF_TO_BE] = &&ALU_END_TO_BE,
+ [BPF_ALU | BPF_END | BPF_TO_LE] = &&ALU_END_TO_LE,
+ /* 64 bit ALU operations */
+ [BPF_ALU64 | BPF_ADD | BPF_X] = &&ALU64_ADD_X,
+ [BPF_ALU64 | BPF_ADD | BPF_K] = &&ALU64_ADD_K,
+ [BPF_ALU64 | BPF_SUB | BPF_X] = &&ALU64_SUB_X,
+ [BPF_ALU64 | BPF_SUB | BPF_K] = &&ALU64_SUB_K,
+ [BPF_ALU64 | BPF_AND | BPF_X] = &&ALU64_AND_X,
+ [BPF_ALU64 | BPF_AND | BPF_K] = &&ALU64_AND_K,
+ [BPF_ALU64 | BPF_OR | BPF_X] = &&ALU64_OR_X,
+ [BPF_ALU64 | BPF_OR | BPF_K] = &&ALU64_OR_K,
+ [BPF_ALU64 | BPF_LSH | BPF_X] = &&ALU64_LSH_X,
+ [BPF_ALU64 | BPF_LSH | BPF_K] = &&ALU64_LSH_K,
+ [BPF_ALU64 | BPF_RSH | BPF_X] = &&ALU64_RSH_X,
+ [BPF_ALU64 | BPF_RSH | BPF_K] = &&ALU64_RSH_K,
+ [BPF_ALU64 | BPF_XOR | BPF_X] = &&ALU64_XOR_X,
+ [BPF_ALU64 | BPF_XOR | BPF_K] = &&ALU64_XOR_K,
+ [BPF_ALU64 | BPF_MUL | BPF_X] = &&ALU64_MUL_X,
+ [BPF_ALU64 | BPF_MUL | BPF_K] = &&ALU64_MUL_K,
+ [BPF_ALU64 | BPF_MOV | BPF_X] = &&ALU64_MOV_X,
+ [BPF_ALU64 | BPF_MOV | BPF_K] = &&ALU64_MOV_K,
+ [BPF_ALU64 | BPF_ARSH | BPF_X] = &&ALU64_ARSH_X,
+ [BPF_ALU64 | BPF_ARSH | BPF_K] = &&ALU64_ARSH_K,
+ [BPF_ALU64 | BPF_DIV | BPF_X] = &&ALU64_DIV_X,
+ [BPF_ALU64 | BPF_DIV | BPF_K] = &&ALU64_DIV_K,
+ [BPF_ALU64 | BPF_MOD | BPF_X] = &&ALU64_MOD_X,
+ [BPF_ALU64 | BPF_MOD | BPF_K] = &&ALU64_MOD_K,
+ [BPF_ALU64 | BPF_NEG] = &&ALU64_NEG,
+ /* Call instruction */
+ [BPF_JMP | BPF_CALL] = &&JMP_CALL,
+ /* Jumps */
+ [BPF_JMP | BPF_JA] = &&JMP_JA,
+ [BPF_JMP | BPF_JEQ | BPF_X] = &&JMP_JEQ_X,
+ [BPF_JMP | BPF_JEQ | BPF_K] = &&JMP_JEQ_K,
+ [BPF_JMP | BPF_JNE | BPF_X] = &&JMP_JNE_X,
+ [BPF_JMP | BPF_JNE | BPF_K] = &&JMP_JNE_K,
+ [BPF_JMP | BPF_JGT | BPF_X] = &&JMP_JGT_X,
+ [BPF_JMP | BPF_JGT | BPF_K] = &&JMP_JGT_K,
+ [BPF_JMP | BPF_JGE | BPF_X] = &&JMP_JGE_X,
+ [BPF_JMP | BPF_JGE | BPF_K] = &&JMP_JGE_K,
+ [BPF_JMP | BPF_JSGT | BPF_X] = &&JMP_JSGT_X,
+ [BPF_JMP | BPF_JSGT | BPF_K] = &&JMP_JSGT_K,
+ [BPF_JMP | BPF_JSGE | BPF_X] = &&JMP_JSGE_X,
+ [BPF_JMP | BPF_JSGE | BPF_K] = &&JMP_JSGE_K,
+ [BPF_JMP | BPF_JSET | BPF_X] = &&JMP_JSET_X,
+ [BPF_JMP | BPF_JSET | BPF_K] = &&JMP_JSET_K,
+ /* Program return */
+ [BPF_JMP | BPF_EXIT] = &&JMP_EXIT,
+ /* Store instructions */
+ [BPF_STX | BPF_MEM | BPF_B] = &&STX_MEM_B,
+ [BPF_STX | BPF_MEM | BPF_H] = &&STX_MEM_H,
+ [BPF_STX | BPF_MEM | BPF_W] = &&STX_MEM_W,
+ [BPF_STX | BPF_MEM | BPF_DW] = &&STX_MEM_DW,
+ [BPF_STX | BPF_XADD | BPF_W] = &&STX_XADD_W,
+ [BPF_STX | BPF_XADD | BPF_DW] = &&STX_XADD_DW,
+ [BPF_ST | BPF_MEM | BPF_B] = &&ST_MEM_B,
+ [BPF_ST | BPF_MEM | BPF_H] = &&ST_MEM_H,
+ [BPF_ST | BPF_MEM | BPF_W] = &&ST_MEM_W,
+ [BPF_ST | BPF_MEM | BPF_DW] = &&ST_MEM_DW,
+ /* Load instructions */
+ [BPF_LDX | BPF_MEM | BPF_B] = &&LDX_MEM_B,
+ [BPF_LDX | BPF_MEM | BPF_H] = &&LDX_MEM_H,
+ [BPF_LDX | BPF_MEM | BPF_W] = &&LDX_MEM_W,
+ [BPF_LDX | BPF_MEM | BPF_DW] = &&LDX_MEM_DW,
+ [BPF_LD | BPF_ABS | BPF_W] = &&LD_ABS_W,
+ [BPF_LD | BPF_ABS | BPF_H] = &&LD_ABS_H,
+ [BPF_LD | BPF_ABS | BPF_B] = &&LD_ABS_B,
+ [BPF_LD | BPF_IND | BPF_W] = &&LD_IND_W,
+ [BPF_LD | BPF_IND | BPF_H] = &&LD_IND_H,
+ [BPF_LD | BPF_IND | BPF_B] = &&LD_IND_B,
+ };
+ void *ptr;
+ int off;
+
+#define CONT ({ insn++; goto select_insn; })
+#define CONT_JMP ({ insn++; goto select_insn; })
+
+ FP = (u64) (unsigned long) &stack[ARRAY_SIZE(stack)];
+ ARG1 = (u64) (unsigned long) ctx;
+
+ /* Registers used in classic BPF programs need to be reset first. */
+ regs[BPF_REG_A] = 0;
+ regs[BPF_REG_X] = 0;
+
+select_insn:
+ goto *jumptable[insn->code];
+
+ /* ALU */
+#define ALU(OPCODE, OP) \
+ ALU64_##OPCODE##_X: \
+ DST = DST OP SRC; \
+ CONT; \
+ ALU_##OPCODE##_X: \
+ DST = (u32) DST OP (u32) SRC; \
+ CONT; \
+ ALU64_##OPCODE##_K: \
+ DST = DST OP IMM; \
+ CONT; \
+ ALU_##OPCODE##_K: \
+ DST = (u32) DST OP (u32) IMM; \
+ CONT;
+
+ ALU(ADD, +)
+ ALU(SUB, -)
+ ALU(AND, &)
+ ALU(OR, |)
+ ALU(LSH, <<)
+ ALU(RSH, >>)
+ ALU(XOR, ^)
+ ALU(MUL, *)
+#undef ALU
+ ALU_NEG:
+ DST = (u32) -DST;
+ CONT;
+ ALU64_NEG:
+ DST = -DST;
+ CONT;
+ ALU_MOV_X:
+ DST = (u32) SRC;
+ CONT;
+ ALU_MOV_K:
+ DST = (u32) IMM;
+ CONT;
+ ALU64_MOV_X:
+ DST = SRC;
+ CONT;
+ ALU64_MOV_K:
+ DST = IMM;
+ CONT;
+ ALU64_ARSH_X:
+ (*(s64 *) &DST) >>= SRC;
+ CONT;
+ ALU64_ARSH_K:
+ (*(s64 *) &DST) >>= IMM;
+ CONT;
+ ALU64_MOD_X:
+ if (unlikely(SRC == 0))
+ return 0;
+ tmp = DST;
+ DST = do_div(tmp, SRC);
+ CONT;
+ ALU_MOD_X:
+ if (unlikely(SRC == 0))
+ return 0;
+ tmp = (u32) DST;
+ DST = do_div(tmp, (u32) SRC);
+ CONT;
+ ALU64_MOD_K:
+ tmp = DST;
+ DST = do_div(tmp, IMM);
+ CONT;
+ ALU_MOD_K:
+ tmp = (u32) DST;
+ DST = do_div(tmp, (u32) IMM);
+ CONT;
+ ALU64_DIV_X:
+ if (unlikely(SRC == 0))
+ return 0;
+ do_div(DST, SRC);
+ CONT;
+ ALU_DIV_X:
+ if (unlikely(SRC == 0))
+ return 0;
+ tmp = (u32) DST;
+ do_div(tmp, (u32) SRC);
+ DST = (u32) tmp;
+ CONT;
+ ALU64_DIV_K:
+ do_div(DST, IMM);
+ CONT;
+ ALU_DIV_K:
+ tmp = (u32) DST;
+ do_div(tmp, (u32) IMM);
+ DST = (u32) tmp;
+ CONT;
+ ALU_END_TO_BE:
+ switch (IMM) {
+ case 16:
+ DST = (__force u16) cpu_to_be16(DST);
+ break;
+ case 32:
+ DST = (__force u32) cpu_to_be32(DST);
+ break;
+ case 64:
+ DST = (__force u64) cpu_to_be64(DST);
+ break;
+ }
+ CONT;
+ ALU_END_TO_LE:
+ switch (IMM) {
+ case 16:
+ DST = (__force u16) cpu_to_le16(DST);
+ break;
+ case 32:
+ DST = (__force u32) cpu_to_le32(DST);
+ break;
+ case 64:
+ DST = (__force u64) cpu_to_le64(DST);
+ break;
+ }
+ CONT;
+
+ /* CALL */
+ JMP_CALL:
+ /* Function call scratches BPF_R1-BPF_R5 registers,
+ * preserves BPF_R6-BPF_R9, and stores return value
+ * into BPF_R0.
+ */
+ BPF_R0 = (__bpf_call_base + insn->imm)(BPF_R1, BPF_R2, BPF_R3,
+ BPF_R4, BPF_R5);
+ CONT;
+
+ /* JMP */
+ JMP_JA:
+ insn += insn->off;
+ CONT;
+ JMP_JEQ_X:
+ if (DST == SRC) {
+ insn += insn->off;
+ CONT_JMP;
+ }
+ CONT;
+ JMP_JEQ_K:
+ if (DST == IMM) {
+ insn += insn->off;
+ CONT_JMP;
+ }
+ CONT;
+ JMP_JNE_X:
+ if (DST != SRC) {
+ insn += insn->off;
+ CONT_JMP;
+ }
+ CONT;
+ JMP_JNE_K:
+ if (DST != IMM) {
+ insn += insn->off;
+ CONT_JMP;
+ }
+ CONT;
+ JMP_JGT_X:
+ if (DST > SRC) {
+ insn += insn->off;
+ CONT_JMP;
+ }
+ CONT;
+ JMP_JGT_K:
+ if (DST > IMM) {
+ insn += insn->off;
+ CONT_JMP;
+ }
+ CONT;
+ JMP_JGE_X:
+ if (DST >= SRC) {
+ insn += insn->off;
+ CONT_JMP;
+ }
+ CONT;
+ JMP_JGE_K:
+ if (DST >= IMM) {
+ insn += insn->off;
+ CONT_JMP;
+ }
+ CONT;
+ JMP_JSGT_X:
+ if (((s64) DST) > ((s64) SRC)) {
+ insn += insn->off;
+ CONT_JMP;
+ }
+ CONT;
+ JMP_JSGT_K:
+ if (((s64) DST) > ((s64) IMM)) {
+ insn += insn->off;
+ CONT_JMP;
+ }
+ CONT;
+ JMP_JSGE_X:
+ if (((s64) DST) >= ((s64) SRC)) {
+ insn += insn->off;
+ CONT_JMP;
+ }
+ CONT;
+ JMP_JSGE_K:
+ if (((s64) DST) >= ((s64) IMM)) {
+ insn += insn->off;
+ CONT_JMP;
+ }
+ CONT;
+ JMP_JSET_X:
+ if (DST & SRC) {
+ insn += insn->off;
+ CONT_JMP;
+ }
+ CONT;
+ JMP_JSET_K:
+ if (DST & IMM) {
+ insn += insn->off;
+ CONT_JMP;
+ }
+ CONT;
+ JMP_EXIT:
+ return BPF_R0;
+
+ /* STX and ST and LDX*/
+#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)
+ LDST(H, u16)
+ LDST(W, u32)
+ LDST(DW, u64)
+#undef LDST
+ 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 *)(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 + imm32)) */
+ off = IMM;
+load_word:
+ /* BPF_LD + BPD_ABS and BPF_LD + BPF_IND insns are
+ * only appearing in the programs where ctx ==
+ * skb. All programs keep 'ctx' in regs[BPF_REG_CTX]
+ * == BPF_R6, sk_convert_filter() saves it in BPF_R6,
+ * internal BPF verifier will check that BPF_R6 ==
+ * ctx.
+ *
+ * BPF_ABS and BPF_IND are wrappers of function calls,
+ * so they scratch BPF_R1-BPF_R5 registers, preserve
+ * BPF_R6-BPF_R9, and store return value into BPF_R0.
+ *
+ * Implicit input:
+ * ctx == skb == BPF_R6 == CTX
+ *
+ * Explicit input:
+ * SRC == any register
+ * IMM == 32-bit immediate
+ *
+ * Output:
+ * BPF_R0 - 8/16/32-bit skb data converted to cpu endianness
+ */
+
+ ptr = bpf_load_pointer((struct sk_buff *) (unsigned long) 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 + imm32)) */
+ off = IMM;
+load_half:
+ ptr = bpf_load_pointer((struct sk_buff *) (unsigned long) CTX, off, 2, &tmp);
+ if (likely(ptr != NULL)) {
+ BPF_R0 = get_unaligned_be16(ptr);
+ CONT;
+ }
+
+ return 0;
+ LD_ABS_B: /* BPF_R0 = *(u8 *) (skb->data + imm32) */
+ off = IMM;
+load_byte:
+ ptr = bpf_load_pointer((struct sk_buff *) (unsigned long) CTX, off, 1, &tmp);
+ if (likely(ptr != NULL)) {
+ BPF_R0 = *(u8 *)ptr;
+ CONT;
+ }
+
+ return 0;
+ 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 + src_reg + imm32)) */
+ off = IMM + SRC;
+ goto load_half;
+ LD_IND_B: /* BPF_R0 = *(u8 *) (skb->data + src_reg + imm32) */
+ off = IMM + SRC;
+ goto load_byte;
+
+ default_label:
+ /* If we ever reach this, we have a bug somewhere. */
+ WARN_RATELIMIT(1, "unknown opcode %02x\n", insn->code);
+ return 0;
+}
+
+void __weak bpf_int_jit_compile(struct sk_filter *prog)
+{
+}
+
+/**
+ * sk_filter_select_runtime - select execution runtime for BPF program
+ * @fp: sk_filter populated with internal BPF program
+ *
+ * try to JIT internal BPF program, if JIT is not available select interpreter
+ * BPF program will be executed via SK_RUN_FILTER() macro
+ */
+void sk_filter_select_runtime(struct sk_filter *fp)
+{
+ fp->bpf_func = (void *) __sk_run_filter;
+
+ /* Probe if internal BPF can be JITed */
+ bpf_int_jit_compile(fp);
+}
+EXPORT_SYMBOL_GPL(sk_filter_select_runtime);
+
+/* free internal BPF program */
+void sk_filter_free(struct sk_filter *fp)
+{
+ bpf_jit_free(fp);
+}
+EXPORT_SYMBOL_GPL(sk_filter_free);
diff --git a/net/core/filter.c b/net/core/filter.c
index b90ae7fb3b89..1d0e9492e4fa 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -45,45 +45,6 @@
#include <linux/seccomp.h>
#include <linux/if_vlan.h>
-/* Registers */
-#define BPF_R0 regs[BPF_REG_0]
-#define BPF_R1 regs[BPF_REG_1]
-#define BPF_R2 regs[BPF_REG_2]
-#define BPF_R3 regs[BPF_REG_3]
-#define BPF_R4 regs[BPF_REG_4]
-#define BPF_R5 regs[BPF_REG_5]
-#define BPF_R6 regs[BPF_REG_6]
-#define BPF_R7 regs[BPF_REG_7]
-#define BPF_R8 regs[BPF_REG_8]
-#define BPF_R9 regs[BPF_REG_9]
-#define BPF_R10 regs[BPF_REG_10]
-
-/* Named registers */
-#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 IMM insn->imm
-
-/* No hurry in this branch
- *
- * Exported for the bpf jit load helper.
- */
-void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb, int k, unsigned int size)
-{
- u8 *ptr = NULL;
-
- if (k >= SKF_NET_OFF)
- ptr = skb_network_header(skb) + k - SKF_NET_OFF;
- else if (k >= SKF_LL_OFF)
- ptr = skb_mac_header(skb) + k - SKF_LL_OFF;
- if (ptr >= skb->head && ptr + size <= skb_tail_pointer(skb))
- return ptr;
-
- return NULL;
-}
-
/**
* sk_filter - run a packet through a socket filter
* @sk: sock associated with &sk_buff
@@ -126,451 +87,6 @@ int sk_filter(struct sock *sk, struct sk_buff *skb)
}
EXPORT_SYMBOL(sk_filter);
-/* Base function for offset calculation. Needs to go into .text section,
- * therefore keeping it non-static as well; will also be used by JITs
- * anyway later on, so do not let the compiler omit it.
- */
-noinline u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
-{
- return 0;
-}
-
-/**
- * __sk_run_filter - run a filter on a given context
- * @ctx: buffer to run the filter on
- * @insn: filter to apply
- *
- * Decode and apply filter instructions to the skb->data. Return length to
- * keep, 0 for none. @ctx is the data we are operating on, @insn is the
- * array of filter instructions.
- */
-static unsigned int __sk_run_filter(void *ctx, const struct sock_filter_int *insn)
-{
- u64 stack[MAX_BPF_STACK / sizeof(u64)];
- u64 regs[MAX_BPF_REG], tmp;
- static const void *jumptable[256] = {
- [0 ... 255] = &&default_label,
- /* Now overwrite non-defaults ... */
- /* 32 bit ALU operations */
- [BPF_ALU | BPF_ADD | BPF_X] = &&ALU_ADD_X,
- [BPF_ALU | BPF_ADD | BPF_K] = &&ALU_ADD_K,
- [BPF_ALU | BPF_SUB | BPF_X] = &&ALU_SUB_X,
- [BPF_ALU | BPF_SUB | BPF_K] = &&ALU_SUB_K,
- [BPF_ALU | BPF_AND | BPF_X] = &&ALU_AND_X,
- [BPF_ALU | BPF_AND | BPF_K] = &&ALU_AND_K,
- [BPF_ALU | BPF_OR | BPF_X] = &&ALU_OR_X,
- [BPF_ALU | BPF_OR | BPF_K] = &&ALU_OR_K,
- [BPF_ALU | BPF_LSH | BPF_X] = &&ALU_LSH_X,
- [BPF_ALU | BPF_LSH | BPF_K] = &&ALU_LSH_K,
- [BPF_ALU | BPF_RSH | BPF_X] = &&ALU_RSH_X,
- [BPF_ALU | BPF_RSH | BPF_K] = &&ALU_RSH_K,
- [BPF_ALU | BPF_XOR | BPF_X] = &&ALU_XOR_X,
- [BPF_ALU | BPF_XOR | BPF_K] = &&ALU_XOR_K,
- [BPF_ALU | BPF_MUL | BPF_X] = &&ALU_MUL_X,
- [BPF_ALU | BPF_MUL | BPF_K] = &&ALU_MUL_K,
- [BPF_ALU | BPF_MOV | BPF_X] = &&ALU_MOV_X,
- [BPF_ALU | BPF_MOV | BPF_K] = &&ALU_MOV_K,
- [BPF_ALU | BPF_DIV | BPF_X] = &&ALU_DIV_X,
- [BPF_ALU | BPF_DIV | BPF_K] = &&ALU_DIV_K,
- [BPF_ALU | BPF_MOD | BPF_X] = &&ALU_MOD_X,
- [BPF_ALU | BPF_MOD | BPF_K] = &&ALU_MOD_K,
- [BPF_ALU | BPF_NEG] = &&ALU_NEG,
- [BPF_ALU | BPF_END | BPF_TO_BE] = &&ALU_END_TO_BE,
- [BPF_ALU | BPF_END | BPF_TO_LE] = &&ALU_END_TO_LE,
- /* 64 bit ALU operations */
- [BPF_ALU64 | BPF_ADD | BPF_X] = &&ALU64_ADD_X,
- [BPF_ALU64 | BPF_ADD | BPF_K] = &&ALU64_ADD_K,
- [BPF_ALU64 | BPF_SUB | BPF_X] = &&ALU64_SUB_X,
- [BPF_ALU64 | BPF_SUB | BPF_K] = &&ALU64_SUB_K,
- [BPF_ALU64 | BPF_AND | BPF_X] = &&ALU64_AND_X,
- [BPF_ALU64 | BPF_AND | BPF_K] = &&ALU64_AND_K,
- [BPF_ALU64 | BPF_OR | BPF_X] = &&ALU64_OR_X,
- [BPF_ALU64 | BPF_OR | BPF_K] = &&ALU64_OR_K,
- [BPF_ALU64 | BPF_LSH | BPF_X] = &&ALU64_LSH_X,
- [BPF_ALU64 | BPF_LSH | BPF_K] = &&ALU64_LSH_K,
- [BPF_ALU64 | BPF_RSH | BPF_X] = &&ALU64_RSH_X,
- [BPF_ALU64 | BPF_RSH | BPF_K] = &&ALU64_RSH_K,
- [BPF_ALU64 | BPF_XOR | BPF_X] = &&ALU64_XOR_X,
- [BPF_ALU64 | BPF_XOR | BPF_K] = &&ALU64_XOR_K,
- [BPF_ALU64 | BPF_MUL | BPF_X] = &&ALU64_MUL_X,
- [BPF_ALU64 | BPF_MUL | BPF_K] = &&ALU64_MUL_K,
- [BPF_ALU64 | BPF_MOV | BPF_X] = &&ALU64_MOV_X,
- [BPF_ALU64 | BPF_MOV | BPF_K] = &&ALU64_MOV_K,
- [BPF_ALU64 | BPF_ARSH | BPF_X] = &&ALU64_ARSH_X,
- [BPF_ALU64 | BPF_ARSH | BPF_K] = &&ALU64_ARSH_K,
- [BPF_ALU64 | BPF_DIV | BPF_X] = &&ALU64_DIV_X,
- [BPF_ALU64 | BPF_DIV | BPF_K] = &&ALU64_DIV_K,
- [BPF_ALU64 | BPF_MOD | BPF_X] = &&ALU64_MOD_X,
- [BPF_ALU64 | BPF_MOD | BPF_K] = &&ALU64_MOD_K,
- [BPF_ALU64 | BPF_NEG] = &&ALU64_NEG,
- /* Call instruction */
- [BPF_JMP | BPF_CALL] = &&JMP_CALL,
- /* Jumps */
- [BPF_JMP | BPF_JA] = &&JMP_JA,
- [BPF_JMP | BPF_JEQ | BPF_X] = &&JMP_JEQ_X,
- [BPF_JMP | BPF_JEQ | BPF_K] = &&JMP_JEQ_K,
- [BPF_JMP | BPF_JNE | BPF_X] = &&JMP_JNE_X,
- [BPF_JMP | BPF_JNE | BPF_K] = &&JMP_JNE_K,
- [BPF_JMP | BPF_JGT | BPF_X] = &&JMP_JGT_X,
- [BPF_JMP | BPF_JGT | BPF_K] = &&JMP_JGT_K,
- [BPF_JMP | BPF_JGE | BPF_X] = &&JMP_JGE_X,
- [BPF_JMP | BPF_JGE | BPF_K] = &&JMP_JGE_K,
- [BPF_JMP | BPF_JSGT | BPF_X] = &&JMP_JSGT_X,
- [BPF_JMP | BPF_JSGT | BPF_K] = &&JMP_JSGT_K,
- [BPF_JMP | BPF_JSGE | BPF_X] = &&JMP_JSGE_X,
- [BPF_JMP | BPF_JSGE | BPF_K] = &&JMP_JSGE_K,
- [BPF_JMP | BPF_JSET | BPF_X] = &&JMP_JSET_X,
- [BPF_JMP | BPF_JSET | BPF_K] = &&JMP_JSET_K,
- /* Program return */
- [BPF_JMP | BPF_EXIT] = &&JMP_EXIT,
- /* Store instructions */
- [BPF_STX | BPF_MEM | BPF_B] = &&STX_MEM_B,
- [BPF_STX | BPF_MEM | BPF_H] = &&STX_MEM_H,
- [BPF_STX | BPF_MEM | BPF_W] = &&STX_MEM_W,
- [BPF_STX | BPF_MEM | BPF_DW] = &&STX_MEM_DW,
- [BPF_STX | BPF_XADD | BPF_W] = &&STX_XADD_W,
- [BPF_STX | BPF_XADD | BPF_DW] = &&STX_XADD_DW,
- [BPF_ST | BPF_MEM | BPF_B] = &&ST_MEM_B,
- [BPF_ST | BPF_MEM | BPF_H] = &&ST_MEM_H,
- [BPF_ST | BPF_MEM | BPF_W] = &&ST_MEM_W,
- [BPF_ST | BPF_MEM | BPF_DW] = &&ST_MEM_DW,
- /* Load instructions */
- [BPF_LDX | BPF_MEM | BPF_B] = &&LDX_MEM_B,
- [BPF_LDX | BPF_MEM | BPF_H] = &&LDX_MEM_H,
- [BPF_LDX | BPF_MEM | BPF_W] = &&LDX_MEM_W,
- [BPF_LDX | BPF_MEM | BPF_DW] = &&LDX_MEM_DW,
- [BPF_LD | BPF_ABS | BPF_W] = &&LD_ABS_W,
- [BPF_LD | BPF_ABS | BPF_H] = &&LD_ABS_H,
- [BPF_LD | BPF_ABS | BPF_B] = &&LD_ABS_B,
- [BPF_LD | BPF_IND | BPF_W] = &&LD_IND_W,
- [BPF_LD | BPF_IND | BPF_H] = &&LD_IND_H,
- [BPF_LD | BPF_IND | BPF_B] = &&LD_IND_B,
- };
- void *ptr;
- int off;
-
-#define CONT ({ insn++; goto select_insn; })
-#define CONT_JMP ({ insn++; goto select_insn; })
-
- FP = (u64) (unsigned long) &stack[ARRAY_SIZE(stack)];
- ARG1 = (u64) (unsigned long) ctx;
-
- /* Registers used in classic BPF programs need to be reset first. */
- regs[BPF_REG_A] = 0;
- regs[BPF_REG_X] = 0;
-
-select_insn:
- goto *jumptable[insn->code];
-
- /* ALU */
-#define ALU(OPCODE, OP) \
- ALU64_##OPCODE##_X: \
- DST = DST OP SRC; \
- CONT; \
- ALU_##OPCODE##_X: \
- DST = (u32) DST OP (u32) SRC; \
- CONT; \
- ALU64_##OPCODE##_K: \
- DST = DST OP IMM; \
- CONT; \
- ALU_##OPCODE##_K: \
- DST = (u32) DST OP (u32) IMM; \
- CONT;
-
- ALU(ADD, +)
- ALU(SUB, -)
- ALU(AND, &)
- ALU(OR, |)
- ALU(LSH, <<)
- ALU(RSH, >>)
- ALU(XOR, ^)
- ALU(MUL, *)
-#undef ALU
- ALU_NEG:
- DST = (u32) -DST;
- CONT;
- ALU64_NEG:
- DST = -DST;
- CONT;
- ALU_MOV_X:
- DST = (u32) SRC;
- CONT;
- ALU_MOV_K:
- DST = (u32) IMM;
- CONT;
- ALU64_MOV_X:
- DST = SRC;
- CONT;
- ALU64_MOV_K:
- DST = IMM;
- CONT;
- ALU64_ARSH_X:
- (*(s64 *) &DST) >>= SRC;
- CONT;
- ALU64_ARSH_K:
- (*(s64 *) &DST) >>= IMM;
- CONT;
- ALU64_MOD_X:
- if (unlikely(SRC == 0))
- return 0;
- tmp = DST;
- DST = do_div(tmp, SRC);
- CONT;
- ALU_MOD_X:
- if (unlikely(SRC == 0))
- return 0;
- tmp = (u32) DST;
- DST = do_div(tmp, (u32) SRC);
- CONT;
- ALU64_MOD_K:
- tmp = DST;
- DST = do_div(tmp, IMM);
- CONT;
- ALU_MOD_K:
- tmp = (u32) DST;
- DST = do_div(tmp, (u32) IMM);
- CONT;
- ALU64_DIV_X:
- if (unlikely(SRC == 0))
- return 0;
- do_div(DST, SRC);
- CONT;
- ALU_DIV_X:
- if (unlikely(SRC == 0))
- return 0;
- tmp = (u32) DST;
- do_div(tmp, (u32) SRC);
- DST = (u32) tmp;
- CONT;
- ALU64_DIV_K:
- do_div(DST, IMM);
- CONT;
- ALU_DIV_K:
- tmp = (u32) DST;
- do_div(tmp, (u32) IMM);
- DST = (u32) tmp;
- CONT;
- ALU_END_TO_BE:
- switch (IMM) {
- case 16:
- DST = (__force u16) cpu_to_be16(DST);
- break;
- case 32:
- DST = (__force u32) cpu_to_be32(DST);
- break;
- case 64:
- DST = (__force u64) cpu_to_be64(DST);
- break;
- }
- CONT;
- ALU_END_TO_LE:
- switch (IMM) {
- case 16:
- DST = (__force u16) cpu_to_le16(DST);
- break;
- case 32:
- DST = (__force u32) cpu_to_le32(DST);
- break;
- case 64:
- DST = (__force u64) cpu_to_le64(DST);
- break;
- }
- CONT;
-
- /* CALL */
- JMP_CALL:
- /* Function call scratches BPF_R1-BPF_R5 registers,
- * preserves BPF_R6-BPF_R9, and stores return value
- * into BPF_R0.
- */
- BPF_R0 = (__bpf_call_base + insn->imm)(BPF_R1, BPF_R2, BPF_R3,
- BPF_R4, BPF_R5);
- CONT;
-
- /* JMP */
- JMP_JA:
- insn += insn->off;
- CONT;
- JMP_JEQ_X:
- if (DST == SRC) {
- insn += insn->off;
- CONT_JMP;
- }
- CONT;
- JMP_JEQ_K:
- if (DST == IMM) {
- insn += insn->off;
- CONT_JMP;
- }
- CONT;
- JMP_JNE_X:
- if (DST != SRC) {
- insn += insn->off;
- CONT_JMP;
- }
- CONT;
- JMP_JNE_K:
- if (DST != IMM) {
- insn += insn->off;
- CONT_JMP;
- }
- CONT;
- JMP_JGT_X:
- if (DST > SRC) {
- insn += insn->off;
- CONT_JMP;
- }
- CONT;
- JMP_JGT_K:
- if (DST > IMM) {
- insn += insn->off;
- CONT_JMP;
- }
- CONT;
- JMP_JGE_X:
- if (DST >= SRC) {
- insn += insn->off;
- CONT_JMP;
- }
- CONT;
- JMP_JGE_K:
- if (DST >= IMM) {
- insn += insn->off;
- CONT_JMP;
- }
- CONT;
- JMP_JSGT_X:
- if (((s64) DST) > ((s64) SRC)) {
- insn += insn->off;
- CONT_JMP;
- }
- CONT;
- JMP_JSGT_K:
- if (((s64) DST) > ((s64) IMM)) {
- insn += insn->off;
- CONT_JMP;
- }
- CONT;
- JMP_JSGE_X:
- if (((s64) DST) >= ((s64) SRC)) {
- insn += insn->off;
- CONT_JMP;
- }
- CONT;
- JMP_JSGE_K:
- if (((s64) DST) >= ((s64) IMM)) {
- insn += insn->off;
- CONT_JMP;
- }
- CONT;
- JMP_JSET_X:
- if (DST & SRC) {
- insn += insn->off;
- CONT_JMP;
- }
- CONT;
- JMP_JSET_K:
- if (DST & IMM) {
- insn += insn->off;
- CONT_JMP;
- }
- CONT;
- JMP_EXIT:
- return BPF_R0;
-
- /* STX and ST and LDX*/
-#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)
- LDST(H, u16)
- LDST(W, u32)
- LDST(DW, u64)
-#undef LDST
- 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 *)(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 + imm32)) */
- off = IMM;
-load_word:
- /* BPF_LD + BPD_ABS and BPF_LD + BPF_IND insns are
- * only appearing in the programs where ctx ==
- * skb. All programs keep 'ctx' in regs[BPF_REG_CTX]
- * == BPF_R6, sk_convert_filter() saves it in BPF_R6,
- * internal BPF verifier will check that BPF_R6 ==
- * ctx.
- *
- * BPF_ABS and BPF_IND are wrappers of function calls,
- * so they scratch BPF_R1-BPF_R5 registers, preserve
- * BPF_R6-BPF_R9, and store return value into BPF_R0.
- *
- * Implicit input:
- * ctx == skb == BPF_R6 == CTX
- *
- * Explicit input:
- * SRC == any register
- * IMM == 32-bit immediate
- *
- * Output:
- * BPF_R0 - 8/16/32-bit skb data converted to cpu endianness
- */
-
- ptr = bpf_load_pointer((struct sk_buff *) (unsigned long) 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 + imm32)) */
- off = IMM;
-load_half:
- ptr = bpf_load_pointer((struct sk_buff *) (unsigned long) CTX, off, 2, &tmp);
- if (likely(ptr != NULL)) {
- BPF_R0 = get_unaligned_be16(ptr);
- CONT;
- }
-
- return 0;
- LD_ABS_B: /* BPF_R0 = *(u8 *) (skb->data + imm32) */
- off = IMM;
-load_byte:
- ptr = bpf_load_pointer((struct sk_buff *) (unsigned long) CTX, off, 1, &tmp);
- if (likely(ptr != NULL)) {
- BPF_R0 = *(u8 *)ptr;
- CONT;
- }
-
- return 0;
- 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 + src_reg + imm32)) */
- off = IMM + SRC;
- goto load_half;
- LD_IND_B: /* BPF_R0 = *(u8 *) (skb->data + src_reg + imm32) */
- off = IMM + SRC;
- goto load_byte;
-
- default_label:
- /* If we ever reach this, we have a bug somewhere. */
- WARN_RATELIMIT(1, "unknown opcode %02x\n", insn->code);
- return 0;
-}
-
/* Helper to find the offset of pkt_type in sk_buff structure. We want
* to make sure its still a 3bit field starting at a byte boundary;
* taken from arch/x86/net/bpf_jit_comp.c.
@@ -1455,33 +971,6 @@ out_err:
return ERR_PTR(err);
}
-void __weak bpf_int_jit_compile(struct sk_filter *prog)
-{
-}
-
-/**
- * sk_filter_select_runtime - select execution runtime for BPF program
- * @fp: sk_filter populated with internal BPF program
- *
- * try to JIT internal BPF program, if JIT is not available select interpreter
- * BPF program will be executed via SK_RUN_FILTER() macro
- */
-void sk_filter_select_runtime(struct sk_filter *fp)
-{
- fp->bpf_func = (void *) __sk_run_filter;
-
- /* Probe if internal BPF can be JITed */
- bpf_int_jit_compile(fp);
-}
-EXPORT_SYMBOL_GPL(sk_filter_select_runtime);
-
-/* free internal BPF program */
-void sk_filter_free(struct sk_filter *fp)
-{
- bpf_jit_free(fp);
-}
-EXPORT_SYMBOL_GPL(sk_filter_free);
-
static struct sk_filter *__sk_prepare_filter(struct sk_filter *fp,
struct sock *sk)
{
--
1.7.9.5
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