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14#include <linux/bpf.h>
15
16#include "disasm.h"
17
18#define __BPF_FUNC_STR_FN(x) [BPF_FUNC_ ## x] = __stringify(bpf_ ## x)
19static const char * const func_id_str[] = {
20 __BPF_FUNC_MAPPER(__BPF_FUNC_STR_FN)
21};
22#undef __BPF_FUNC_STR_FN
23
24static const char *__func_get_name(const struct bpf_insn_cbs *cbs,
25 const struct bpf_insn *insn,
26 char *buff, size_t len)
27{
28 BUILD_BUG_ON(ARRAY_SIZE(func_id_str) != __BPF_FUNC_MAX_ID);
29
30 if (insn->src_reg != BPF_PSEUDO_CALL &&
31 insn->imm >= 0 && insn->imm < __BPF_FUNC_MAX_ID &&
32 func_id_str[insn->imm])
33 return func_id_str[insn->imm];
34
35 if (cbs && cbs->cb_call)
36 return cbs->cb_call(cbs->private_data, insn);
37
38 if (insn->src_reg == BPF_PSEUDO_CALL)
39 snprintf(buff, len, "%+d", insn->imm);
40
41 return buff;
42}
43
44static const char *__func_imm_name(const struct bpf_insn_cbs *cbs,
45 const struct bpf_insn *insn,
46 u64 full_imm, char *buff, size_t len)
47{
48 if (cbs && cbs->cb_imm)
49 return cbs->cb_imm(cbs->private_data, insn, full_imm);
50
51 snprintf(buff, len, "0x%llx", (unsigned long long)full_imm);
52 return buff;
53}
54
55const char *func_id_name(int id)
56{
57 if (id >= 0 && id < __BPF_FUNC_MAX_ID && func_id_str[id])
58 return func_id_str[id];
59 else
60 return "unknown";
61}
62
63const char *const bpf_class_string[8] = {
64 [BPF_LD] = "ld",
65 [BPF_LDX] = "ldx",
66 [BPF_ST] = "st",
67 [BPF_STX] = "stx",
68 [BPF_ALU] = "alu",
69 [BPF_JMP] = "jmp",
70 [BPF_JMP32] = "jmp32",
71 [BPF_ALU64] = "alu64",
72};
73
74const char *const bpf_alu_string[16] = {
75 [BPF_ADD >> 4] = "+=",
76 [BPF_SUB >> 4] = "-=",
77 [BPF_MUL >> 4] = "*=",
78 [BPF_DIV >> 4] = "/=",
79 [BPF_OR >> 4] = "|=",
80 [BPF_AND >> 4] = "&=",
81 [BPF_LSH >> 4] = "<<=",
82 [BPF_RSH >> 4] = ">>=",
83 [BPF_NEG >> 4] = "neg",
84 [BPF_MOD >> 4] = "%=",
85 [BPF_XOR >> 4] = "^=",
86 [BPF_MOV >> 4] = "=",
87 [BPF_ARSH >> 4] = "s>>=",
88 [BPF_END >> 4] = "endian",
89};
90
91static const char *const bpf_ldst_string[] = {
92 [BPF_W >> 3] = "u32",
93 [BPF_H >> 3] = "u16",
94 [BPF_B >> 3] = "u8",
95 [BPF_DW >> 3] = "u64",
96};
97
98static const char *const bpf_jmp_string[16] = {
99 [BPF_JA >> 4] = "jmp",
100 [BPF_JEQ >> 4] = "==",
101 [BPF_JGT >> 4] = ">",
102 [BPF_JLT >> 4] = "<",
103 [BPF_JGE >> 4] = ">=",
104 [BPF_JLE >> 4] = "<=",
105 [BPF_JSET >> 4] = "&",
106 [BPF_JNE >> 4] = "!=",
107 [BPF_JSGT >> 4] = "s>",
108 [BPF_JSLT >> 4] = "s<",
109 [BPF_JSGE >> 4] = "s>=",
110 [BPF_JSLE >> 4] = "s<=",
111 [BPF_CALL >> 4] = "call",
112 [BPF_EXIT >> 4] = "exit",
113};
114
115static void print_bpf_end_insn(bpf_insn_print_t verbose,
116 void *private_data,
117 const struct bpf_insn *insn)
118{
119 verbose(private_data, "(%02x) r%d = %s%d r%d\n",
120 insn->code, insn->dst_reg,
121 BPF_SRC(insn->code) == BPF_TO_BE ? "be" : "le",
122 insn->imm, insn->dst_reg);
123}
124
125void print_bpf_insn(const struct bpf_insn_cbs *cbs,
126 const struct bpf_insn *insn,
127 bool allow_ptr_leaks)
128{
129 const bpf_insn_print_t verbose = cbs->cb_print;
130 u8 class = BPF_CLASS(insn->code);
131
132 if (class == BPF_ALU || class == BPF_ALU64) {
133 if (BPF_OP(insn->code) == BPF_END) {
134 if (class == BPF_ALU64)
135 verbose(cbs->private_data, "BUG_alu64_%02x\n", insn->code);
136 else
137 print_bpf_end_insn(verbose, cbs->private_data, insn);
138 } else if (BPF_OP(insn->code) == BPF_NEG) {
139 verbose(cbs->private_data, "(%02x) %c%d = -%c%d\n",
140 insn->code, class == BPF_ALU ? 'w' : 'r',
141 insn->dst_reg, class == BPF_ALU ? 'w' : 'r',
142 insn->dst_reg);
143 } else if (BPF_SRC(insn->code) == BPF_X) {
144 verbose(cbs->private_data, "(%02x) %c%d %s %c%d\n",
145 insn->code, class == BPF_ALU ? 'w' : 'r',
146 insn->dst_reg,
147 bpf_alu_string[BPF_OP(insn->code) >> 4],
148 class == BPF_ALU ? 'w' : 'r',
149 insn->src_reg);
150 } else {
151 verbose(cbs->private_data, "(%02x) %c%d %s %d\n",
152 insn->code, class == BPF_ALU ? 'w' : 'r',
153 insn->dst_reg,
154 bpf_alu_string[BPF_OP(insn->code) >> 4],
155 insn->imm);
156 }
157 } else if (class == BPF_STX) {
158 if (BPF_MODE(insn->code) == BPF_MEM)
159 verbose(cbs->private_data, "(%02x) *(%s *)(r%d %+d) = r%d\n",
160 insn->code,
161 bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
162 insn->dst_reg,
163 insn->off, insn->src_reg);
164 else if (BPF_MODE(insn->code) == BPF_XADD)
165 verbose(cbs->private_data, "(%02x) lock *(%s *)(r%d %+d) += r%d\n",
166 insn->code,
167 bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
168 insn->dst_reg, insn->off,
169 insn->src_reg);
170 else
171 verbose(cbs->private_data, "BUG_%02x\n", insn->code);
172 } else if (class == BPF_ST) {
173 if (BPF_MODE(insn->code) != BPF_MEM) {
174 verbose(cbs->private_data, "BUG_st_%02x\n", insn->code);
175 return;
176 }
177 verbose(cbs->private_data, "(%02x) *(%s *)(r%d %+d) = %d\n",
178 insn->code,
179 bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
180 insn->dst_reg,
181 insn->off, insn->imm);
182 } else if (class == BPF_LDX) {
183 if (BPF_MODE(insn->code) != BPF_MEM) {
184 verbose(cbs->private_data, "BUG_ldx_%02x\n", insn->code);
185 return;
186 }
187 verbose(cbs->private_data, "(%02x) r%d = *(%s *)(r%d %+d)\n",
188 insn->code, insn->dst_reg,
189 bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
190 insn->src_reg, insn->off);
191 } else if (class == BPF_LD) {
192 if (BPF_MODE(insn->code) == BPF_ABS) {
193 verbose(cbs->private_data, "(%02x) r0 = *(%s *)skb[%d]\n",
194 insn->code,
195 bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
196 insn->imm);
197 } else if (BPF_MODE(insn->code) == BPF_IND) {
198 verbose(cbs->private_data, "(%02x) r0 = *(%s *)skb[r%d + %d]\n",
199 insn->code,
200 bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
201 insn->src_reg, insn->imm);
202 } else if (BPF_MODE(insn->code) == BPF_IMM &&
203 BPF_SIZE(insn->code) == BPF_DW) {
204
205
206
207 u64 imm = ((u64)(insn + 1)->imm << 32) | (u32)insn->imm;
208 bool map_ptr = insn->src_reg == BPF_PSEUDO_MAP_FD;
209 char tmp[64];
210
211 if (map_ptr && !allow_ptr_leaks)
212 imm = 0;
213
214 verbose(cbs->private_data, "(%02x) r%d = %s\n",
215 insn->code, insn->dst_reg,
216 __func_imm_name(cbs, insn, imm,
217 tmp, sizeof(tmp)));
218 } else {
219 verbose(cbs->private_data, "BUG_ld_%02x\n", insn->code);
220 return;
221 }
222 } else if (class == BPF_JMP32 || class == BPF_JMP) {
223 u8 opcode = BPF_OP(insn->code);
224
225 if (opcode == BPF_CALL) {
226 char tmp[64];
227
228 if (insn->src_reg == BPF_PSEUDO_CALL) {
229 verbose(cbs->private_data, "(%02x) call pc%s\n",
230 insn->code,
231 __func_get_name(cbs, insn,
232 tmp, sizeof(tmp)));
233 } else {
234 strcpy(tmp, "unknown");
235 verbose(cbs->private_data, "(%02x) call %s#%d\n", insn->code,
236 __func_get_name(cbs, insn,
237 tmp, sizeof(tmp)),
238 insn->imm);
239 }
240 } else if (insn->code == (BPF_JMP | BPF_JA)) {
241 verbose(cbs->private_data, "(%02x) goto pc%+d\n",
242 insn->code, insn->off);
243 } else if (insn->code == (BPF_JMP | BPF_EXIT)) {
244 verbose(cbs->private_data, "(%02x) exit\n", insn->code);
245 } else if (BPF_SRC(insn->code) == BPF_X) {
246 verbose(cbs->private_data,
247 "(%02x) if %c%d %s %c%d goto pc%+d\n",
248 insn->code, class == BPF_JMP32 ? 'w' : 'r',
249 insn->dst_reg,
250 bpf_jmp_string[BPF_OP(insn->code) >> 4],
251 class == BPF_JMP32 ? 'w' : 'r',
252 insn->src_reg, insn->off);
253 } else {
254 verbose(cbs->private_data,
255 "(%02x) if %c%d %s 0x%x goto pc%+d\n",
256 insn->code, class == BPF_JMP32 ? 'w' : 'r',
257 insn->dst_reg,
258 bpf_jmp_string[BPF_OP(insn->code) >> 4],
259 insn->imm, insn->off);
260 }
261 } else {
262 verbose(cbs->private_data, "(%02x) %s\n",
263 insn->code, bpf_class_string[class]);
264 }
265}
266
