1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
|
// SPDX-License-Identifier: GPL-2.0-only
/* 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, "BUG_st_%02x\n", insn->code);
return;
}
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 (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]);
}
}
|
