1 /* $NetBSD: support.c,v 1.2 2014/10/18 08:33:23 snj Exp $ */
2
3 /*
4 * Portions Copyright (c) 1995-1998 by Trusted Information Systems, Inc.
5 *
6 * Permission to use, copy modify, and distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
9 *
10 * THE SOFTWARE IS PROVIDED "AS IS" AND TRUSTED INFORMATION SYSTEMS
11 * DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL
12 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
13 * TRUSTED INFORMATION SYSTEMS BE LIABLE FOR ANY SPECIAL, DIRECT,
14 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
15 * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
16 * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
17 * WITH THE USE OR PERFORMANCE OF THE SOFTWARE.
18 */
19 #include <sys/cdefs.h>
20 #if 0
21 static const char rcsid[] = "Header: /proj/cvs/prod/libbind/dst/support.c,v 1.6 2005/10/11 00:10:13 marka Exp ";
22 #endif
23
24 #include "port_before.h"
25
26 #include <stdio.h>
27 #include <unistd.h>
28 #include <memory.h>
29 #include <string.h>
30 #include <errno.h>
31 #include <sys/stat.h>
32 #include <netinet/in.h>
33 #include <arpa/nameser.h>
34 #include <resolv.h>
35
36 #include "dst_internal.h"
37
38 #include "port_after.h"
39
40 /*%
41 * dst_s_verify_str()
42 * Validate that the input string(*str) is at the head of the input
43 * buffer(**buf). If so, move the buffer head pointer (*buf) to
44 * the first byte of data following the string(*str).
45 * Parameters
46 * buf Input buffer.
47 * str Input string.
48 * Return
49 * 0 *str is not the head of **buff
50 * 1 *str is the head of **buff, *buf is is advanced to
51 * the tail of **buf.
52 */
53
54 int
dst_s_verify_str(const char ** buf,const char * str)55 dst_s_verify_str(const char **buf, const char *str)
56 {
57 size_t b, s;
58 if (*buf == NULL) /*%< error checks */
59 return (0);
60 if (str == NULL || *str == '\0')
61 return (1);
62
63 b = strlen(*buf); /*%< get length of strings */
64 s = strlen(str);
65 if (s > b || strncmp(*buf, str, s)) /*%< check if same */
66 return (0); /*%< not a match */
67 (*buf) += s; /*%< advance pointer */
68 return (1);
69 }
70
71 /*%
72 * dst_s_calculate_bits
73 * Given a binary number represented in a u_char[], determine
74 * the number of significant bits used.
75 * Parameters
76 * str An input character string containing a binary number.
77 * max_bits The maximum possible significant bits.
78 * Return
79 * N The number of significant bits in str.
80 */
81
82 int
dst_s_calculate_bits(const u_char * str,const int max_bits)83 dst_s_calculate_bits(const u_char *str, const int max_bits)
84 {
85 const u_char *p = str;
86 u_char i, j = 0x80;
87 int bits;
88 for (bits = max_bits; *p == 0x00 && bits > 0; p++)
89 bits -= 8;
90 for (i = *p; (i & j) != j; j >>= 1)
91 bits--;
92 return (bits);
93 }
94
95 /*%
96 * calculates a checksum used in dst for an id.
97 * takes an array of bytes and a length.
98 * returns a 16 bit checksum.
99 */
100 u_int16_t
dst_s_id_calc(const u_char * key,const int keysize)101 dst_s_id_calc(const u_char *key, const int keysize)
102 {
103 u_int32_t ac;
104 const u_char *kp = key;
105 int size = keysize;
106
107 if (!key || (keysize <= 0))
108 return (0xffffU);
109
110 for (ac = 0; size > 1; size -= 2, kp += 2)
111 ac += ((*kp) << 8) + *(kp + 1);
112
113 if (size > 0)
114 ac += ((*kp) << 8);
115 ac += (ac >> 16) & 0xffff;
116
117 return (ac & 0xffff);
118 }
119
120 /*%
121 * dst_s_dns_key_id() Function to calculate DNSSEC footprint from KEY record
122 * rdata
123 * Input:
124 * dns_key_rdata: the raw data in wire format
125 * rdata_len: the size of the input data
126 * Output:
127 * the key footprint/id calculated from the key data
128 */
129 u_int16_t
dst_s_dns_key_id(const u_char * dns_key_rdata,const int rdata_len)130 dst_s_dns_key_id(const u_char *dns_key_rdata, const int rdata_len)
131 {
132 if (!dns_key_rdata)
133 return 0;
134
135 /* compute id */
136 if (dns_key_rdata[3] == KEY_RSA) /*%< Algorithm RSA */
137 return dst_s_get_int16((const u_char *)
138 &dns_key_rdata[rdata_len - 3]);
139 else if (dns_key_rdata[3] == KEY_HMAC_MD5)
140 /* compatibility */
141 return 0;
142 else
143 /* compute a checksum on the key part of the key rr */
144 return dst_s_id_calc(dns_key_rdata, rdata_len);
145 }
146
147 /*%
148 * dst_s_get_int16
149 * This routine extracts a 16 bit integer from a two byte character
150 * string. The character string is assumed to be in network byte
151 * order and may be unaligned. The number returned is in host order.
152 * Parameter
153 * buf A two byte character string.
154 * Return
155 * The converted integer value.
156 */
157
158 u_int16_t
dst_s_get_int16(const u_char * buf)159 dst_s_get_int16(const u_char *buf)
160 {
161 register u_int16_t a = 0;
162 a = ((u_int16_t)(buf[0] << 8)) | ((u_int16_t)(buf[1]));
163 return (a);
164 }
165
166 /*%
167 * dst_s_get_int32
168 * This routine extracts a 32 bit integer from a four byte character
169 * string. The character string is assumed to be in network byte
170 * order and may be unaligned. The number returned is in host order.
171 * Parameter
172 * buf A four byte character string.
173 * Return
174 * The converted integer value.
175 */
176
177 u_int32_t
dst_s_get_int32(const u_char * buf)178 dst_s_get_int32(const u_char *buf)
179 {
180 register u_int32_t a = 0;
181 a = ((u_int32_t)(buf[0] << 24)) | ((u_int32_t)(buf[1] << 16)) |
182 ((u_int32_t)(buf[2] << 8)) | ((u_int32_t)(buf[3]));
183 return (a);
184 }
185
186 /*%
187 * dst_s_put_int16
188 * Take a 16 bit integer and store the value in a two byte
189 * character string. The integer is assumed to be in network
190 * order and the string is returned in host order.
191 *
192 * Parameters
193 * buf Storage for a two byte character string.
194 * val 16 bit integer.
195 */
196
197 void
dst_s_put_int16(u_int8_t * buf,const u_int16_t val)198 dst_s_put_int16(u_int8_t *buf, const u_int16_t val)
199 {
200 buf[0] = (u_int8_t)((uint32_t)val >> 8);
201 buf[1] = (u_int8_t)(val);
202 }
203
204 /*%
205 * dst_s_put_int32
206 * Take a 32 bit integer and store the value in a four byte
207 * character string. The integer is assumed to be in network
208 * order and the string is returned in host order.
209 *
210 * Parameters
211 * buf Storage for a four byte character string.
212 * val 32 bit integer.
213 */
214
215 void
dst_s_put_int32(u_int8_t * buf,const u_int32_t val)216 dst_s_put_int32(u_int8_t *buf, const u_int32_t val)
217 {
218 buf[0] = (u_int8_t)(val >> 24);
219 buf[1] = (u_int8_t)(val >> 16);
220 buf[2] = (u_int8_t)(val >> 8);
221 buf[3] = (u_int8_t)(val);
222 }
223
224 /*%
225 * dst_s_filename_length
226 *
227 * This function returns the number of bytes needed to hold the
228 * filename for a key file. '/', '\' and ':' are not allowed.
229 * form: K<keyname>+<alg>+<id>.<suffix>
230 *
231 * Returns 0 if the filename would contain either '\', '/' or ':'
232 */
233 size_t
dst_s_filename_length(const char * name,const char * suffix)234 dst_s_filename_length(const char *name, const char *suffix)
235 {
236 if (name == NULL)
237 return (0);
238 if (strrchr(name, '\\'))
239 return (0);
240 if (strrchr(name, '/'))
241 return (0);
242 if (strrchr(name, ':'))
243 return (0);
244 if (suffix == NULL)
245 return (0);
246 if (strrchr(suffix, '\\'))
247 return (0);
248 if (strrchr(suffix, '/'))
249 return (0);
250 if (strrchr(suffix, ':'))
251 return (0);
252 return (1 + strlen(name) + 6 + strlen(suffix));
253 }
254
255 /*%
256 * dst_s_build_filename ()
257 * Builds a key filename from the key name, its id, and a
258 * suffix. '\', '/' and ':' are not allowed. fA filename is of the
259 * form: K<keyname><id>.<suffix>
260 * form: K<keyname>+<alg>+<id>.<suffix>
261 *
262 * Returns -1 if the conversion fails:
263 * if the filename would be too long for space allotted
264 * if the filename would contain a '\', '/' or ':'
265 * Returns 0 on success
266 */
267
268 int
dst_s_build_filename(char * filename,const char * name,u_int16_t id,int alg,const char * suffix,size_t filename_length)269 dst_s_build_filename(char *filename, const char *name, u_int16_t id,
270 int alg, const char *suffix, size_t filename_length)
271 {
272 u_int32_t my_id;
273 if (filename == NULL)
274 return (-1);
275 memset(filename, 0, filename_length);
276 if (name == NULL)
277 return (-1);
278 if (suffix == NULL)
279 return (-1);
280 if (filename_length < 1 + strlen(name) + 4 + 6 + 1 + strlen(suffix))
281 return (-1);
282 my_id = id;
283 sprintf(filename, "K%s+%03d+%05d.%s", name, alg, my_id,
284 (const char *) suffix);
285 if (strrchr(filename, '/'))
286 return (-1);
287 if (strrchr(filename, '\\'))
288 return (-1);
289 if (strrchr(filename, ':'))
290 return (-1);
291 return (0);
292 }
293
294 /*%
295 * dst_s_fopen ()
296 * Open a file in the dst_path directory. If perm is specified, the
297 * file is checked for existence first, and not opened if it exists.
298 * Parameters
299 * filename File to open
300 * mode Mode to open the file (passed directly to fopen)
301 * perm File permission, if creating a new file.
302 * Returns
303 * NULL Failure
304 * NON-NULL (FILE *) of opened file.
305 */
306 FILE *
dst_s_fopen(const char * filename,const char * mode,int perm)307 dst_s_fopen(const char *filename, const char *mode, int perm)
308 {
309 FILE *fp;
310 char pathname[PATH_MAX];
311
312 if (strlen(filename) + strlen(dst_path) >= sizeof(pathname))
313 return (NULL);
314
315 if (*dst_path != '\0') {
316 strcpy(pathname, dst_path);
317 strcat(pathname, filename);
318 } else
319 strcpy(pathname, filename);
320
321 fp = fopen(pathname, mode);
322 if (perm)
323 chmod(pathname, (mode_t)perm);
324 return (fp);
325 }
326
327 void
dst_s_dump(const int mode,const u_char * data,const int size,const char * msg)328 dst_s_dump(const int mode, const u_char *data, const int size,
329 const char *msg)
330 {
331 UNUSED(data);
332
333 if (size > 0) {
334 #ifdef LONG_TEST
335 static u_char scratch[1000];
336 int n ;
337 n = b64_ntop(data, scratch, size, sizeof(scratch));
338 printf("%s: %x %d %s\n", msg, mode, n, scratch);
339 #else
340 printf("%s,%x %d\n", msg, mode, size);
341 #endif
342 }
343 }
344
345 /*! \file */
346