Some small changes in preparation for a bigger change.

- typedef for ABC variables and MAX_ABC_LENGTH constant,
- cast pc->k to uint32_t in more places,
- whitespaces.
This commit is contained in:
alnsn 2014-05-22 13:35:45 +00:00
parent 7b9bf19905
commit 74e580d299
1 changed files with 26 additions and 19 deletions

View File

@ -1,4 +1,4 @@
/* $NetBSD: bpfjit.c,v 1.7 2014/05/15 22:20:08 alnsn Exp $ */
/* $NetBSD: bpfjit.c,v 1.8 2014/05/22 13:35:45 alnsn Exp $ */
/*-
* Copyright (c) 2011-2014 Alexander Nasonov.
@ -31,9 +31,9 @@
#include <sys/cdefs.h>
#ifdef _KERNEL
__KERNEL_RCSID(0, "$NetBSD: bpfjit.c,v 1.7 2014/05/15 22:20:08 alnsn Exp $");
__KERNEL_RCSID(0, "$NetBSD: bpfjit.c,v 1.8 2014/05/22 13:35:45 alnsn Exp $");
#else
__RCSID("$NetBSD: bpfjit.c,v 1.7 2014/05/15 22:20:08 alnsn Exp $");
__RCSID("$NetBSD: bpfjit.c,v 1.8 2014/05/22 13:35:45 alnsn Exp $");
#endif
#include <sys/types.h>
@ -94,6 +94,9 @@ typedef unsigned int bpfjit_init_mask_t;
#define BJ_INIT_ABIT BJ_INIT_MBIT(BPF_MEMWORDS)
#define BJ_INIT_XBIT BJ_INIT_MBIT(BPF_MEMWORDS + 1)
typedef uint32_t bpfjit_abc_length_t;
#define MAX_ABC_LENGTH UINT32_MAX
struct bpfjit_stack
{
uint32_t mem[BPF_MEMWORDS];
@ -130,11 +133,11 @@ struct bpfjit_jump_data {
/*
* Length calculated by Array Bounds Check Elimination (ABC) pass.
*/
uint32_t abc_length;
bpfjit_abc_length_t abc_length;
/*
* Length checked by the last out-of-bounds check.
*/
uint32_t checked_length;
bpfjit_abc_length_t checked_length;
};
/*
@ -145,14 +148,14 @@ struct bpfjit_read_pkt_data {
/*
* Length calculated by Array Bounds Check Elimination (ABC) pass.
*/
uint32_t abc_length;
bpfjit_abc_length_t abc_length;
/*
* If positive, emit "if (buflen < check_length) return 0"
* out-of-bounds check.
* We assume that buflen is never equal to UINT32_MAX (otherwise,
* we'd need a special bool variable to emit unconditional "return 0").
*/
uint32_t check_length;
bpfjit_abc_length_t check_length;
};
/*
@ -876,10 +879,10 @@ emit_division(struct sljit_compiler* compiler, int divt, sljit_w divw)
* be set to a safe length required to read a packet.
*/
static bool
read_pkt_insn(const struct bpf_insn *pc, uint32_t *length)
read_pkt_insn(const struct bpf_insn *pc, bpfjit_abc_length_t *length)
{
bool rv;
uint32_t width;
bpfjit_abc_length_t width;
switch (BPF_CLASS(pc->code)) {
default:
@ -1067,7 +1070,7 @@ optimize_pass1(const struct bpf_insn *insns,
case BPF_JMP:
/* Initialize abc_length for ABC pass. */
insn_dat[i].u.jdata.abc_length = UINT32_MAX;
insn_dat[i].u.jdata.abc_length = MAX_ABC_LENGTH;
if (BPF_OP(insns[i].code) == BPF_JA) {
jt = jf = insns[i].k;
@ -1123,7 +1126,7 @@ optimize_pass2(const struct bpf_insn *insns,
const struct bpf_insn *pc;
struct bpfjit_insn_data *pd;
size_t i;
uint32_t length, abc_length = 0;
bpfjit_abc_length_t length, abc_length = 0;
for (i = insn_count; i != 0; i--) {
pc = &insns[i-1];
@ -1163,7 +1166,7 @@ optimize_pass3(const struct bpf_insn *insns,
{
struct bpfjit_jump *jmp;
size_t i;
uint32_t length, checked_length = 0;
bpfjit_abc_length_t checked_length = 0;
for (i = 0; i < insn_count; i++) {
if (insn_dat[i].unreachable)
@ -1176,7 +1179,7 @@ optimize_pass3(const struct bpf_insn *insns,
if (BPF_CLASS(insns[i].code) == BPF_JMP) {
insn_dat[i].u.jdata.checked_length = checked_length;
} else if (read_pkt_insn(&insns[i], &length)) {
} else if (read_pkt_insn(&insns[i], NULL)) {
struct bpfjit_read_pkt_data *rdata =
&insn_dat[i].u.rdata;
rdata->check_length = 0;
@ -1427,7 +1430,7 @@ bpfjit_generate_code(bpf_ctx_t *bc, struct bpf_insn *insns, size_t insn_count)
SLJIT_IMM,
insn_dat[i].u.rdata.check_length);
if (jump == NULL)
goto fail;
goto fail;
#ifdef _KERNEL
to_mchain_jump = jump;
#else
@ -1458,7 +1461,7 @@ bpfjit_generate_code(bpf_ctx_t *bc, struct bpf_insn *insns, size_t insn_count)
/* BPF_LD+BPF_MEM A <- M[k] */
if (pc->code == (BPF_LD|BPF_MEM)) {
if (pc->k >= BPF_MEMWORDS)
if ((uint32_t)pc->k >= BPF_MEMWORDS)
goto fail;
status = sljit_emit_op1(compiler,
SLJIT_MOV_UI,
@ -1530,7 +1533,7 @@ bpfjit_generate_code(bpf_ctx_t *bc, struct bpf_insn *insns, size_t insn_count)
if (mode == BPF_MEM) {
if (BPF_SIZE(pc->code) != BPF_W)
goto fail;
if (pc->k >= BPF_MEMWORDS)
if ((uint32_t)pc->k >= BPF_MEMWORDS)
goto fail;
status = sljit_emit_op1(compiler,
SLJIT_MOV_UI,
@ -1556,8 +1559,10 @@ bpfjit_generate_code(bpf_ctx_t *bc, struct bpf_insn *insns, size_t insn_count)
continue;
case BPF_ST:
if (pc->code != BPF_ST || pc->k >= BPF_MEMWORDS)
if (pc->code != BPF_ST ||
(uint32_t)pc->k >= BPF_MEMWORDS) {
goto fail;
}
status = sljit_emit_op1(compiler,
SLJIT_MOV_UI,
@ -1571,8 +1576,10 @@ bpfjit_generate_code(bpf_ctx_t *bc, struct bpf_insn *insns, size_t insn_count)
continue;
case BPF_STX:
if (pc->code != BPF_STX || pc->k >= BPF_MEMWORDS)
if (pc->code != BPF_STX ||
(uint32_t)pc->k >= BPF_MEMWORDS) {
goto fail;
}
status = sljit_emit_op1(compiler,
SLJIT_MOV_UI,
@ -1619,7 +1626,7 @@ bpfjit_generate_code(bpf_ctx_t *bc, struct bpf_insn *insns, size_t insn_count)
if (src == BPF_X) {
jump = sljit_emit_cmp(compiler,
SLJIT_C_EQUAL|SLJIT_INT_OP,
BJ_XREG, 0,
BJ_XREG, 0,
SLJIT_IMM, 0);
if (jump == NULL)
goto fail;