net: filter: split filter.c into two files
authorAlexei Starovoitov <ast@plumgrid.com>
Wed, 23 Jul 2014 06:01:58 +0000 (23:01 -0700)
committerDavid S. Miller <davem@davemloft.net>
Thu, 24 Jul 2014 04:06:22 +0000 (21:06 -0700)
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@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
kernel/Makefile
kernel/bpf/Makefile [new file with mode: 0644]
kernel/bpf/core.c [new file with mode: 0644]
net/core/filter.c

index f2a8b62..e7360b7 100644 (file)
@@ -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 (file)
index 0000000..6a71145
--- /dev/null
@@ -0,0 +1 @@
+obj-y := core.o
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
new file mode 100644 (file)
index 0000000..77a240a
--- /dev/null
@@ -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@samba.org>
+ *     Alexei Starovoitov <ast@plumgrid.com>
+ *     Daniel Borkmann <dborkman@redhat.com>
+ *
+ * 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);
index b90ae7f..1d0e949 100644 (file)
 #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)
 {