diff options
author | Alexei Starovoitov <ast@plumgrid.com> | 2014-07-22 23:01:58 -0700 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2014-07-23 21:06:22 -0700 |
commit | f5bffecda951b59d0d3cdd616d68952abc52bc40 (patch) | |
tree | d41b60043315ff9ea6a7ddcb053e66419d24889c /net/core | |
parent | 8942a6d5f2b60ca374473ee0a996c5e64ce604dc (diff) | |
download | linux-f5bffecda951b59d0d3cdd616d68952abc52bc40.tar.bz2 |
net: filter: split filter.c into two files
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>
Diffstat (limited to 'net/core')
-rw-r--r-- | net/core/filter.c | 511 |
1 files changed, 0 insertions, 511 deletions
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) { |