xref: /freebsd/contrib/libpcap/bpf_image.c (revision 6be3386466ab79a84b48429ae66244f21526d3df)
1 /*
2  * Copyright (c) 1990, 1991, 1992, 1994, 1995, 1996
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that: (1) source code distributions
7  * retain the above copyright notice and this paragraph in its entirety, (2)
8  * distributions including binary code include the above copyright notice and
9  * this paragraph in its entirety in the documentation or other materials
10  * provided with the distribution, and (3) all advertising materials mentioning
11  * features or use of this software display the following acknowledgement:
12  * ``This product includes software developed by the University of California,
13  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14  * the University nor the names of its contributors may be used to endorse
15  * or promote products derived from this software without specific prior
16  * written permission.
17  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
20  */
21 
22 #ifdef HAVE_CONFIG_H
23 #include <config.h>
24 #endif
25 
26 #include <pcap-types.h>
27 
28 #include <stdio.h>
29 #include <string.h>
30 
31 #include "pcap-int.h"
32 
33 #ifdef HAVE_OS_PROTO_H
34 #include "os-proto.h"
35 #endif
36 
37 char *
38 bpf_image(const struct bpf_insn *p, int n)
39 {
40 	const char *op;
41 	static char image[256];
42 	char operand_buf[64];
43 	const char *operand;
44 
45 	switch (p->code) {
46 
47 	default:
48 		op = "unimp";
49 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "0x%x", p->code);
50 		operand = operand_buf;
51 		break;
52 
53 	case BPF_RET|BPF_K:
54 		op = "ret";
55 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "#%d", p->k);
56 		operand = operand_buf;
57 		break;
58 
59 	case BPF_RET|BPF_A:
60 		op = "ret";
61 		operand = "";
62 		break;
63 
64 	case BPF_LD|BPF_W|BPF_ABS:
65 		op = "ld";
66 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "[%d]", p->k);
67 		operand = operand_buf;
68 		break;
69 
70 	case BPF_LD|BPF_H|BPF_ABS:
71 		op = "ldh";
72 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "[%d]", p->k);
73 		operand = operand_buf;
74 		break;
75 
76 	case BPF_LD|BPF_B|BPF_ABS:
77 		op = "ldb";
78 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "[%d]", p->k);
79 		operand = operand_buf;
80 		break;
81 
82 	case BPF_LD|BPF_W|BPF_LEN:
83 		op = "ld";
84 		operand = "#pktlen";
85 		break;
86 
87 	case BPF_LD|BPF_W|BPF_IND:
88 		op = "ld";
89 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "[x + %d]", p->k);
90 		operand = operand_buf;
91 		break;
92 
93 	case BPF_LD|BPF_H|BPF_IND:
94 		op = "ldh";
95 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "[x + %d]", p->k);
96 		operand = operand_buf;
97 		break;
98 
99 	case BPF_LD|BPF_B|BPF_IND:
100 		op = "ldb";
101 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "[x + %d]", p->k);
102 		operand = operand_buf;
103 		break;
104 
105 	case BPF_LD|BPF_IMM:
106 		op = "ld";
107 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "#0x%x", p->k);
108 		operand = operand_buf;
109 		break;
110 
111 	case BPF_LDX|BPF_IMM:
112 		op = "ldx";
113 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "#0x%x", p->k);
114 		operand = operand_buf;
115 		break;
116 
117 	case BPF_LDX|BPF_MSH|BPF_B:
118 		op = "ldxb";
119 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "4*([%d]&0xf)", p->k);
120 		operand = operand_buf;
121 		break;
122 
123 	case BPF_LD|BPF_MEM:
124 		op = "ld";
125 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "M[%d]", p->k);
126 		operand = operand_buf;
127 		break;
128 
129 	case BPF_LDX|BPF_MEM:
130 		op = "ldx";
131 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "M[%d]", p->k);
132 		operand = operand_buf;
133 		break;
134 
135 	case BPF_ST:
136 		op = "st";
137 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "M[%d]", p->k);
138 		operand = operand_buf;
139 		break;
140 
141 	case BPF_STX:
142 		op = "stx";
143 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "M[%d]", p->k);
144 		operand = operand_buf;
145 		break;
146 
147 	case BPF_JMP|BPF_JA:
148 		op = "ja";
149 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "%d", n + 1 + p->k);
150 		operand = operand_buf;
151 		break;
152 
153 	case BPF_JMP|BPF_JGT|BPF_K:
154 		op = "jgt";
155 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "#0x%x", p->k);
156 		operand = operand_buf;
157 		break;
158 
159 	case BPF_JMP|BPF_JGE|BPF_K:
160 		op = "jge";
161 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "#0x%x", p->k);
162 		operand = operand_buf;
163 		break;
164 
165 	case BPF_JMP|BPF_JEQ|BPF_K:
166 		op = "jeq";
167 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "#0x%x", p->k);
168 		operand = operand_buf;
169 		break;
170 
171 	case BPF_JMP|BPF_JSET|BPF_K:
172 		op = "jset";
173 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "#0x%x", p->k);
174 		operand = operand_buf;
175 		break;
176 
177 	case BPF_JMP|BPF_JGT|BPF_X:
178 		op = "jgt";
179 		operand = "x";
180 		break;
181 
182 	case BPF_JMP|BPF_JGE|BPF_X:
183 		op = "jge";
184 		operand = "x";
185 		break;
186 
187 	case BPF_JMP|BPF_JEQ|BPF_X:
188 		op = "jeq";
189 		operand = "x";
190 		break;
191 
192 	case BPF_JMP|BPF_JSET|BPF_X:
193 		op = "jset";
194 		operand = "x";
195 		break;
196 
197 	case BPF_ALU|BPF_ADD|BPF_X:
198 		op = "add";
199 		operand = "x";
200 		break;
201 
202 	case BPF_ALU|BPF_SUB|BPF_X:
203 		op = "sub";
204 		operand = "x";
205 		break;
206 
207 	case BPF_ALU|BPF_MUL|BPF_X:
208 		op = "mul";
209 		operand = "x";
210 		break;
211 
212 	case BPF_ALU|BPF_DIV|BPF_X:
213 		op = "div";
214 		operand = "x";
215 		break;
216 
217 	case BPF_ALU|BPF_MOD|BPF_X:
218 		op = "mod";
219 		operand = "x";
220 		break;
221 
222 	case BPF_ALU|BPF_AND|BPF_X:
223 		op = "and";
224 		operand = "x";
225 		break;
226 
227 	case BPF_ALU|BPF_OR|BPF_X:
228 		op = "or";
229 		operand = "x";
230 		break;
231 
232 	case BPF_ALU|BPF_XOR|BPF_X:
233 		op = "xor";
234 		operand = "x";
235 		break;
236 
237 	case BPF_ALU|BPF_LSH|BPF_X:
238 		op = "lsh";
239 		operand = "x";
240 		break;
241 
242 	case BPF_ALU|BPF_RSH|BPF_X:
243 		op = "rsh";
244 		operand = "x";
245 		break;
246 
247 	case BPF_ALU|BPF_ADD|BPF_K:
248 		op = "add";
249 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "#%d", p->k);
250 		operand = operand_buf;
251 		break;
252 
253 	case BPF_ALU|BPF_SUB|BPF_K:
254 		op = "sub";
255 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "#%d", p->k);
256 		operand = operand_buf;
257 		break;
258 
259 	case BPF_ALU|BPF_MUL|BPF_K:
260 		op = "mul";
261 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "#%d", p->k);
262 		operand = operand_buf;
263 		break;
264 
265 	case BPF_ALU|BPF_DIV|BPF_K:
266 		op = "div";
267 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "#%d", p->k);
268 		operand = operand_buf;
269 		break;
270 
271 	case BPF_ALU|BPF_MOD|BPF_K:
272 		op = "mod";
273 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "#%d", p->k);
274 		operand = operand_buf;
275 		break;
276 
277 	case BPF_ALU|BPF_AND|BPF_K:
278 		op = "and";
279 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "#0x%x", p->k);
280 		operand = operand_buf;
281 		break;
282 
283 	case BPF_ALU|BPF_OR|BPF_K:
284 		op = "or";
285 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "#0x%x", p->k);
286 		operand = operand_buf;
287 		break;
288 
289 	case BPF_ALU|BPF_XOR|BPF_K:
290 		op = "xor";
291 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "#0x%x", p->k);
292 		operand = operand_buf;
293 		break;
294 
295 	case BPF_ALU|BPF_LSH|BPF_K:
296 		op = "lsh";
297 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "#%d", p->k);
298 		operand = operand_buf;
299 		break;
300 
301 	case BPF_ALU|BPF_RSH|BPF_K:
302 		op = "rsh";
303 		(void)pcap_snprintf(operand_buf, sizeof operand_buf, "#%d", p->k);
304 		operand = operand_buf;
305 		break;
306 
307 	case BPF_ALU|BPF_NEG:
308 		op = "neg";
309 		operand = "";
310 		break;
311 
312 	case BPF_MISC|BPF_TAX:
313 		op = "tax";
314 		operand = "";
315 		break;
316 
317 	case BPF_MISC|BPF_TXA:
318 		op = "txa";
319 		operand = "";
320 		break;
321 	}
322 	if (BPF_CLASS(p->code) == BPF_JMP && BPF_OP(p->code) != BPF_JA) {
323 		(void)pcap_snprintf(image, sizeof image,
324 			      "(%03d) %-8s %-16s jt %d\tjf %d",
325 			      n, op, operand, n + 1 + p->jt, n + 1 + p->jf);
326 	} else {
327 		(void)pcap_snprintf(image, sizeof image,
328 			      "(%03d) %-8s %s",
329 			      n, op, operand);
330 	}
331 	return image;
332 }
333