305 lines
9.2 KiB
C
305 lines
9.2 KiB
C
|
// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
|
||
|
|
/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
|
||
|
|
* Copyright (c) 2016 Facebook
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <linux/bpf.h>
|
||
|
|
|
||
|
|
#include "disasm.h"
|
||
|
|
|
||
|
|
#define __BPF_FUNC_STR_FN(x) [BPF_FUNC_ ## x] = __stringify(bpf_ ## x)
|
||
|
|
static const char * const func_id_str[] = {
|
||
|
|
__BPF_FUNC_MAPPER(__BPF_FUNC_STR_FN)
|
||
|
|
};
|
||
|
|
#undef __BPF_FUNC_STR_FN
|
||
|
|
|
||
|
|
static const char *__func_get_name(const struct bpf_insn_cbs *cbs,
|
||
|
|
const struct bpf_insn *insn,
|
||
|
|
char *buff, size_t len)
|
||
|
|
{
|
||
|
|
BUILD_BUG_ON(ARRAY_SIZE(func_id_str) != __BPF_FUNC_MAX_ID);
|
||
|
|
|
||
|
|
if (!insn->src_reg &&
|
||
|
|
insn->imm >= 0 && insn->imm < __BPF_FUNC_MAX_ID &&
|
||
|
|
func_id_str[insn->imm])
|
||
|
|
return func_id_str[insn->imm];
|
||
|
|
|
||
|
|
if (cbs && cbs->cb_call) {
|
||
|
|
const char *res;
|
||
|
|
|
||
|
|
res = cbs->cb_call(cbs->private_data, insn);
|
||
|
|
if (res)
|
||
|
|
return res;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (insn->src_reg == BPF_PSEUDO_CALL)
|
||
|
|
snprintf(buff, len, "%+d", insn->imm);
|
||
|
|
else if (insn->src_reg == BPF_PSEUDO_KFUNC_CALL)
|
||
|
|
snprintf(buff, len, "kernel-function");
|
||
|
|
|
||
|
|
return buff;
|
||
|
|
}
|
||
|
|
|
||
|
|
static const char *__func_imm_name(const struct bpf_insn_cbs *cbs,
|
||
|
|
const struct bpf_insn *insn,
|
||
|
|
u64 full_imm, char *buff, size_t len)
|
||
|
|
{
|
||
|
|
if (cbs && cbs->cb_imm)
|
||
|
|
return cbs->cb_imm(cbs->private_data, insn, full_imm);
|
||
|
|
|
||
|
|
snprintf(buff, len, "0x%llx", (unsigned long long)full_imm);
|
||
|
|
return buff;
|
||
|
|
}
|
||
|
|
|
||
|
|
const char *func_id_name(int id)
|
||
|
|
{
|
||
|
|
if (id >= 0 && id < __BPF_FUNC_MAX_ID && func_id_str[id])
|
||
|
|
return func_id_str[id];
|
||
|
|
else
|
||
|
|
return "unknown";
|
||
|
|
}
|
||
|
|
|
||
|
|
const char *const bpf_class_string[8] = {
|
||
|
|
[BPF_LD] = "ld",
|
||
|
|
[BPF_LDX] = "ldx",
|
||
|
|
[BPF_ST] = "st",
|
||
|
|
[BPF_STX] = "stx",
|
||
|
|
[BPF_ALU] = "alu",
|
||
|
|
[BPF_JMP] = "jmp",
|
||
|
|
[BPF_JMP32] = "jmp32",
|
||
|
|
[BPF_ALU64] = "alu64",
|
||
|
|
};
|
||
|
|
|
||
|
|
const char *const bpf_alu_string[16] = {
|
||
|
|
[BPF_ADD >> 4] = "+=",
|
||
|
|
[BPF_SUB >> 4] = "-=",
|
||
|
|
[BPF_MUL >> 4] = "*=",
|
||
|
|
[BPF_DIV >> 4] = "/=",
|
||
|
|
[BPF_OR >> 4] = "|=",
|
||
|
|
[BPF_AND >> 4] = "&=",
|
||
|
|
[BPF_LSH >> 4] = "<<=",
|
||
|
|
[BPF_RSH >> 4] = ">>=",
|
||
|
|
[BPF_NEG >> 4] = "neg",
|
||
|
|
[BPF_MOD >> 4] = "%=",
|
||
|
|
[BPF_XOR >> 4] = "^=",
|
||
|
|
[BPF_MOV >> 4] = "=",
|
||
|
|
[BPF_ARSH >> 4] = "s>>=",
|
||
|
|
[BPF_END >> 4] = "endian",
|
||
|
|
};
|
||
|
|
|
||
|
|
static const char *const bpf_atomic_alu_string[16] = {
|
||
|
|
[BPF_ADD >> 4] = "add",
|
||
|
|
[BPF_AND >> 4] = "and",
|
||
|
|
[BPF_OR >> 4] = "or",
|
||
|
|
[BPF_XOR >> 4] = "xor",
|
||
|
|
};
|
||
|
|
|
||
|
|
static const char *const bpf_ldst_string[] = {
|
||
|
|
[BPF_W >> 3] = "u32",
|
||
|
|
[BPF_H >> 3] = "u16",
|
||
|
|
[BPF_B >> 3] = "u8",
|
||
|
|
[BPF_DW >> 3] = "u64",
|
||
|
|
};
|
||
|
|
|
||
|
|
static const char *const bpf_jmp_string[16] = {
|
||
|
|
[BPF_JA >> 4] = "jmp",
|
||
|
|
[BPF_JEQ >> 4] = "==",
|
||
|
|
[BPF_JGT >> 4] = ">",
|
||
|
|
[BPF_JLT >> 4] = "<",
|
||
|
|
[BPF_JGE >> 4] = ">=",
|
||
|
|
[BPF_JLE >> 4] = "<=",
|
||
|
|
[BPF_JSET >> 4] = "&",
|
||
|
|
[BPF_JNE >> 4] = "!=",
|
||
|
|
[BPF_JSGT >> 4] = "s>",
|
||
|
|
[BPF_JSLT >> 4] = "s<",
|
||
|
|
[BPF_JSGE >> 4] = "s>=",
|
||
|
|
[BPF_JSLE >> 4] = "s<=",
|
||
|
|
[BPF_CALL >> 4] = "call",
|
||
|
|
[BPF_EXIT >> 4] = "exit",
|
||
|
|
};
|
||
|
|
|
||
|
|
static void print_bpf_end_insn(bpf_insn_print_t verbose,
|
||
|
|
void *private_data,
|
||
|
|
const struct bpf_insn *insn)
|
||
|
|
{
|
||
|
|
verbose(private_data, "(%02x) r%d = %s%d r%d\n",
|
||
|
|
insn->code, insn->dst_reg,
|
||
|
|
BPF_SRC(insn->code) == BPF_TO_BE ? "be" : "le",
|
||
|
|
insn->imm, insn->dst_reg);
|
||
|
|
}
|
||
|
|
|
||
|
|
void print_bpf_insn(const struct bpf_insn_cbs *cbs,
|
||
|
|
const struct bpf_insn *insn,
|
||
|
|
bool allow_ptr_leaks)
|
||
|
|
{
|
||
|
|
const bpf_insn_print_t verbose = cbs->cb_print;
|
||
|
|
u8 class = BPF_CLASS(insn->code);
|
||
|
|
|
||
|
|
if (class == BPF_ALU || class == BPF_ALU64) {
|
||
|
|
if (BPF_OP(insn->code) == BPF_END) {
|
||
|
|
if (class == BPF_ALU64)
|
||
|
|
verbose(cbs->private_data, "BUG_alu64_%02x\n", insn->code);
|
||
|
|
else
|
||
|
|
print_bpf_end_insn(verbose, cbs->private_data, insn);
|
||
|
|
} else if (BPF_OP(insn->code) == BPF_NEG) {
|
||
|
|
verbose(cbs->private_data, "(%02x) %c%d = -%c%d\n",
|
||
|
|
insn->code, class == BPF_ALU ? 'w' : 'r',
|
||
|
|
insn->dst_reg, class == BPF_ALU ? 'w' : 'r',
|
||
|
|
insn->dst_reg);
|
||
|
|
} else if (BPF_SRC(insn->code) == BPF_X) {
|
||
|
|
verbose(cbs->private_data, "(%02x) %c%d %s %c%d\n",
|
||
|
|
insn->code, class == BPF_ALU ? 'w' : 'r',
|
||
|
|
insn->dst_reg,
|
||
|
|
bpf_alu_string[BPF_OP(insn->code) >> 4],
|
||
|
|
class == BPF_ALU ? 'w' : 'r',
|
||
|
|
insn->src_reg);
|
||
|
|
} else {
|
||
|
|
verbose(cbs->private_data, "(%02x) %c%d %s %d\n",
|
||
|
|
insn->code, class == BPF_ALU ? 'w' : 'r',
|
||
|
|
insn->dst_reg,
|
||
|
|
bpf_alu_string[BPF_OP(insn->code) >> 4],
|
||
|
|
insn->imm);
|
||
|
|
}
|
||
|
|
} else if (class == BPF_STX) {
|
||
|
|
if (BPF_MODE(insn->code) == BPF_MEM)
|
||
|
|
verbose(cbs->private_data, "(%02x) *(%s *)(r%d %+d) = r%d\n",
|
||
|
|
insn->code,
|
||
|
|
bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
|
||
|
|
insn->dst_reg,
|
||
|
|
insn->off, insn->src_reg);
|
||
|
|
else if (BPF_MODE(insn->code) == BPF_ATOMIC &&
|
||
|
|
(insn->imm == BPF_ADD || insn->imm == BPF_AND ||
|
||
|
|
insn->imm == BPF_OR || insn->imm == BPF_XOR)) {
|
||
|
|
verbose(cbs->private_data, "(%02x) lock *(%s *)(r%d %+d) %s r%d\n",
|
||
|
|
insn->code,
|
||
|
|
bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
|
||
|
|
insn->dst_reg, insn->off,
|
||
|
|
bpf_alu_string[BPF_OP(insn->imm) >> 4],
|
||
|
|
insn->src_reg);
|
||
|
|
} else if (BPF_MODE(insn->code) == BPF_ATOMIC &&
|
||
|
|
(insn->imm == (BPF_ADD | BPF_FETCH) ||
|
||
|
|
insn->imm == (BPF_AND | BPF_FETCH) ||
|
||
|
|
insn->imm == (BPF_OR | BPF_FETCH) ||
|
||
|
|
insn->imm == (BPF_XOR | BPF_FETCH))) {
|
||
|
|
verbose(cbs->private_data, "(%02x) r%d = atomic%s_fetch_%s((%s *)(r%d %+d), r%d)\n",
|
||
|
|
insn->code, insn->src_reg,
|
||
|
|
BPF_SIZE(insn->code) == BPF_DW ? "64" : "",
|
||
|
|
bpf_atomic_alu_string[BPF_OP(insn->imm) >> 4],
|
||
|
|
bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
|
||
|
|
insn->dst_reg, insn->off, insn->src_reg);
|
||
|
|
} else if (BPF_MODE(insn->code) == BPF_ATOMIC &&
|
||
|
|
insn->imm == BPF_CMPXCHG) {
|
||
|
|
verbose(cbs->private_data, "(%02x) r0 = atomic%s_cmpxchg((%s *)(r%d %+d), r0, r%d)\n",
|
||
|
|
insn->code,
|
||
|
|
BPF_SIZE(insn->code) == BPF_DW ? "64" : "",
|
||
|
|
bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
|
||
|
|
insn->dst_reg, insn->off,
|
||
|
|
insn->src_reg);
|
||
|
|
} else if (BPF_MODE(insn->code) == BPF_ATOMIC &&
|
||
|
|
insn->imm == BPF_XCHG) {
|
||
|
|
verbose(cbs->private_data, "(%02x) r%d = atomic%s_xchg((%s *)(r%d %+d), r%d)\n",
|
||
|
|
insn->code, insn->src_reg,
|
||
|
|
BPF_SIZE(insn->code) == BPF_DW ? "64" : "",
|
||
|
|
bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
|
||
|
|
insn->dst_reg, insn->off, insn->src_reg);
|
||
|
|
} else {
|
||
|
|
verbose(cbs->private_data, "BUG_%02x\n", insn->code);
|
||
|
|
}
|
||
|
|
} else if (class == BPF_ST) {
|
||
|
|
if (BPF_MODE(insn->code) == BPF_MEM) {
|
||
|
|
verbose(cbs->private_data, "(%02x) *(%s *)(r%d %+d) = %d\n",
|
||
|
|
insn->code,
|
||
|
|
bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
|
||
|
|
insn->dst_reg,
|
||
|
|
insn->off, insn->imm);
|
||
|
|
} else if (BPF_MODE(insn->code) == 0xc0 /* BPF_NOSPEC, no UAPI */) {
|
||
|
|
verbose(cbs->private_data, "(%02x) nospec\n", insn->code);
|
||
|
|
} else {
|
||
|
|
verbose(cbs->private_data, "BUG_st_%02x\n", insn->code);
|
||
|
|
}
|
||
|
|
} else if (class == BPF_LDX) {
|
||
|
|
if (BPF_MODE(insn->code) != BPF_MEM) {
|
||
|
|
verbose(cbs->private_data, "BUG_ldx_%02x\n", insn->code);
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
verbose(cbs->private_data, "(%02x) r%d = *(%s *)(r%d %+d)\n",
|
||
|
|
insn->code, insn->dst_reg,
|
||
|
|
bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
|
||
|
|
insn->src_reg, insn->off);
|
||
|
|
} else if (class == BPF_LD) {
|
||
|
|
if (BPF_MODE(insn->code) == BPF_ABS) {
|
||
|
|
verbose(cbs->private_data, "(%02x) r0 = *(%s *)skb[%d]\n",
|
||
|
|
insn->code,
|
||
|
|
bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
|
||
|
|
insn->imm);
|
||
|
|
} else if (BPF_MODE(insn->code) == BPF_IND) {
|
||
|
|
verbose(cbs->private_data, "(%02x) r0 = *(%s *)skb[r%d + %d]\n",
|
||
|
|
insn->code,
|
||
|
|
bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
|
||
|
|
insn->src_reg, insn->imm);
|
||
|
|
} else if (BPF_MODE(insn->code) == BPF_IMM &&
|
||
|
|
BPF_SIZE(insn->code) == BPF_DW) {
|
||
|
|
/* At this point, we already made sure that the second
|
||
|
|
* part of the ldimm64 insn is accessible.
|
||
|
|
*/
|
||
|
|
u64 imm = ((u64)(insn + 1)->imm << 32) | (u32)insn->imm;
|
||
|
|
bool is_ptr = insn->src_reg == BPF_PSEUDO_MAP_FD ||
|
||
|
|
insn->src_reg == BPF_PSEUDO_MAP_VALUE;
|
||
|
|
char tmp[64];
|
||
|
|
|
||
|
|
if (is_ptr && !allow_ptr_leaks)
|
||
|
|
imm = 0;
|
||
|
|
|
||
|
|
verbose(cbs->private_data, "(%02x) r%d = %s\n",
|
||
|
|
insn->code, insn->dst_reg,
|
||
|
|
__func_imm_name(cbs, insn, imm,
|
||
|
|
tmp, sizeof(tmp)));
|
||
|
|
} else {
|
||
|
|
verbose(cbs->private_data, "BUG_ld_%02x\n", insn->code);
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
} else if (class == BPF_JMP32 || class == BPF_JMP) {
|
||
|
|
u8 opcode = BPF_OP(insn->code);
|
||
|
|
|
||
|
|
if (opcode == BPF_CALL) {
|
||
|
|
char tmp[64];
|
||
|
|
|
||
|
|
if (insn->src_reg == BPF_PSEUDO_CALL) {
|
||
|
|
verbose(cbs->private_data, "(%02x) call pc%s\n",
|
||
|
|
insn->code,
|
||
|
|
__func_get_name(cbs, insn,
|
||
|
|
tmp, sizeof(tmp)));
|
||
|
|
} else {
|
||
|
|
strcpy(tmp, "unknown");
|
||
|
|
verbose(cbs->private_data, "(%02x) call %s#%d\n", insn->code,
|
||
|
|
__func_get_name(cbs, insn,
|
||
|
|
tmp, sizeof(tmp)),
|
||
|
|
insn->imm);
|
||
|
|
}
|
||
|
|
} else if (insn->code == (BPF_JMP | BPF_JA)) {
|
||
|
|
verbose(cbs->private_data, "(%02x) goto pc%+d\n",
|
||
|
|
insn->code, insn->off);
|
||
|
|
} else if (insn->code == (BPF_JMP | BPF_EXIT)) {
|
||
|
|
verbose(cbs->private_data, "(%02x) exit\n", insn->code);
|
||
|
|
} else if (BPF_SRC(insn->code) == BPF_X) {
|
||
|
|
verbose(cbs->private_data,
|
||
|
|
"(%02x) if %c%d %s %c%d goto pc%+d\n",
|
||
|
|
insn->code, class == BPF_JMP32 ? 'w' : 'r',
|
||
|
|
insn->dst_reg,
|
||
|
|
bpf_jmp_string[BPF_OP(insn->code) >> 4],
|
||
|
|
class == BPF_JMP32 ? 'w' : 'r',
|
||
|
|
insn->src_reg, insn->off);
|
||
|
|
} else {
|
||
|
|
verbose(cbs->private_data,
|
||
|
|
"(%02x) if %c%d %s 0x%x goto pc%+d\n",
|
||
|
|
insn->code, class == BPF_JMP32 ? 'w' : 'r',
|
||
|
|
insn->dst_reg,
|
||
|
|
bpf_jmp_string[BPF_OP(insn->code) >> 4],
|
||
|
|
insn->imm, insn->off);
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
verbose(cbs->private_data, "(%02x) %s\n",
|
||
|
|
insn->code, bpf_class_string[class]);
|
||
|
|
}
|
||
|
|
}
|