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 #else
23 __RCSID("$NetBSD: support.c,v 1.2 2014/10/18 08:33:23 snj Exp $");
24 #endif
25
26 #include "port_before.h"
27
28 #include <stdio.h>
29 #include <unistd.h>
30 #include <memory.h>
31 #include <string.h>
32 #include <errno.h>
33 #include <sys/stat.h>
34 #include <netinet/in.h>
35 #include <arpa/nameser.h>
36 #include <resolv.h>
37
38 #include "dst_internal.h"
39
40 #include "port_after.h"
41
42 /*%
43 * dst_s_verify_str()
44 * Validate that the input string(*str) is at the head of the input
45 * buffer(**buf). If so, move the buffer head pointer (*buf) to
46 * the first byte of data following the string(*str).
47 * Parameters
48 * buf Input buffer.
49 * str Input string.
50 * Return
51 * 0 *str is not the head of **buff
52 * 1 *str is the head of **buff, *buf is is advanced to
53 * the tail of **buf.
54 */
55
56 int
dst_s_verify_str(const char ** buf,const char * str)57 dst_s_verify_str(const char **buf, const char *str)
58 {
59 size_t b, s;
60 if (*buf == NULL) /*%< error checks */
61 return (0);
62 if (str == NULL || *str == '\0')
63 return (1);
64
65 b = strlen(*buf); /*%< get length of strings */
66 s = strlen(str);
67 if (s > b || strncmp(*buf, str, s)) /*%< check if same */
68 return (0); /*%< not a match */
69 (*buf) += s; /*%< advance pointer */
70 return (1);
71 }
72
73 /*%
74 * dst_s_calculate_bits
75 * Given a binary number represented in a u_char[], determine
76 * the number of significant bits used.
77 * Parameters
78 * str An input character string containing a binary number.
79 * max_bits The maximum possible significant bits.
80 * Return
81 * N The number of significant bits in str.
82 */
83
84 int
dst_s_calculate_bits(const u_char * str,const int max_bits)85 dst_s_calculate_bits(const u_char *str, const int max_bits)
86 {
87 const u_char *p = str;
88 u_char i, j = 0x80;
89 int bits;
90 for (bits = max_bits; *p == 0x00 && bits > 0; p++)
91 bits -= 8;
92 for (i = *p; (i & j) != j; j >>= 1)
93 bits--;
94 return (bits);
95 }
96
97 /*%
98 * calculates a checksum used in dst for an id.
99 * takes an array of bytes and a length.
100 * returns a 16 bit checksum.
101 */
102 u_int16_t
dst_s_id_calc(const u_char * key,const int keysize)103 dst_s_id_calc(const u_char *key, const int keysize)
104 {
105 u_int32_t ac;
106 const u_char *kp = key;
107 int size = keysize;
108
109 if (!key || (keysize <= 0))
110 return (0xffffU);
111
112 for (ac = 0; size > 1; size -= 2, kp += 2)
113 ac += ((*kp) << 8) + *(kp + 1);
114
115 if (size > 0)
116 ac += ((*kp) << 8);
117 ac += (ac >> 16) & 0xffff;
118
119 return (ac & 0xffff);
120 }
121
122 /*%
123 * dst_s_dns_key_id() Function to calculate DNSSEC footprint from KEY record
124 * rdata
125 * Input:
126 * dns_key_rdata: the raw data in wire format
127 * rdata_len: the size of the input data
128 * Output:
129 * the key footprint/id calculated from the key data
130 */
131 u_int16_t
dst_s_dns_key_id(const u_char * dns_key_rdata,const int rdata_len)132 dst_s_dns_key_id(const u_char *dns_key_rdata, const int rdata_len)
133 {
134 if (!dns_key_rdata)
135 return 0;
136
137 /* compute id */
138 if (dns_key_rdata[3] == KEY_RSA) /*%< Algorithm RSA */
139 return dst_s_get_int16((const u_char *)
140 &dns_key_rdata[rdata_len - 3]);
141 else if (dns_key_rdata[3] == KEY_HMAC_MD5)
142 /* compatibility */
143 return 0;
144 else
145 /* compute a checksum on the key part of the key rr */
146 return dst_s_id_calc(dns_key_rdata, rdata_len);
147 }
148
149 /*%
150 * dst_s_get_int16
151 * This routine extracts a 16 bit integer from a two byte character
152 * string. The character string is assumed to be in network byte
153 * order and may be unaligned. The number returned is in host order.
154 * Parameter
155 * buf A two byte character string.
156 * Return
157 * The converted integer value.
158 */
159
160 u_int16_t
dst_s_get_int16(const u_char * buf)161 dst_s_get_int16(const u_char *buf)
162 {
163 register u_int16_t a = 0;
164 a = ((u_int16_t)(buf[0] << 8)) | ((u_int16_t)(buf[1]));
165 return (a);
166 }
167
168 /*%
169 * dst_s_get_int32
170 * This routine extracts a 32 bit integer from a four byte character
171 * string. The character string is assumed to be in network byte
172 * order and may be unaligned. The number returned is in host order.
173 * Parameter
174 * buf A four byte character string.
175 * Return
176 * The converted integer value.
177 */
178
179 u_int32_t
dst_s_get_int32(const u_char * buf)180 dst_s_get_int32(const u_char *buf)
181 {
182 register u_int32_t a = 0;
183 a = ((u_int32_t)(buf[0] << 24)) | ((u_int32_t)(buf[1] << 16)) |
184 ((u_int32_t)(buf[2] << 8)) | ((u_int32_t)(buf[3]));
185 return (a);
186 }
187
188 /*%
189 * dst_s_put_int16
190 * Take a 16 bit integer and store the value in a two byte
191 * character string. The integer is assumed to be in network
192 * order and the string is returned in host order.
193 *
194 * Parameters
195 * buf Storage for a two byte character string.
196 * val 16 bit integer.
197 */
198
199 void
dst_s_put_int16(u_int8_t * buf,const u_int16_t val)200 dst_s_put_int16(u_int8_t *buf, const u_int16_t val)
201 {
202 buf[0] = (u_int8_t)((uint32_t)val >> 8);
203 buf[1] = (u_int8_t)(val);
204 }
205
206 /*%
207 * dst_s_put_int32
208 * Take a 32 bit integer and store the value in a four byte
209 * character string. The integer is assumed to be in network
210 * order and the string is returned in host order.
211 *
212 * Parameters
213 * buf Storage for a four byte character string.
214 * val 32 bit integer.
215 */
216
217 void
dst_s_put_int32(u_int8_t * buf,const u_int32_t val)218 dst_s_put_int32(u_int8_t *buf, const u_int32_t val)
219 {
220 buf[0] = (u_int8_t)(val >> 24);
221 buf[1] = (u_int8_t)(val >> 16);
222 buf[2] = (u_int8_t)(val >> 8);
223 buf[3] = (u_int8_t)(val);
224 }
225
226 /*%
227 * dst_s_filename_length
228 *
229 * This function returns the number of bytes needed to hold the
230 * filename for a key file. '/', '\' and ':' are not allowed.
231 * form: K<keyname>+<alg>+<id>.<suffix>
232 *
233 * Returns 0 if the filename would contain either '\', '/' or ':'
234 */
235 size_t
dst_s_filename_length(const char * name,const char * suffix)236 dst_s_filename_length(const char *name, const char *suffix)
237 {
238 if (name == NULL)
239 return (0);
240 if (strrchr(name, '\\'))
241 return (0);
242 if (strrchr(name, '/'))
243 return (0);
244 if (strrchr(name, ':'))
245 return (0);
246 if (suffix == NULL)
247 return (0);
248 if (strrchr(suffix, '\\'))
249 return (0);
250 if (strrchr(suffix, '/'))
251 return (0);
252 if (strrchr(suffix, ':'))
253 return (0);
254 return (1 + strlen(name) + 6 + strlen(suffix));
255 }
256
257 /*%
258 * dst_s_build_filename ()
259 * Builds a key filename from the key name, its id, and a
260 * suffix. '\', '/' and ':' are not allowed. fA filename is of the
261 * form: K<keyname><id>.<suffix>
262 * form: K<keyname>+<alg>+<id>.<suffix>
263 *
264 * Returns -1 if the conversion fails:
265 * if the filename would be too long for space allotted
266 * if the filename would contain a '\', '/' or ':'
267 * Returns 0 on success
268 */
269
270 int
dst_s_build_filename(char * filename,const char * name,u_int16_t id,int alg,const char * suffix,size_t filename_length)271 dst_s_build_filename(char *filename, const char *name, u_int16_t id,
272 int alg, const char *suffix, size_t filename_length)
273 {
274 u_int32_t my_id;
275 if (filename == NULL)
276 return (-1);
277 memset(filename, 0, filename_length);
278 if (name == NULL)
279 return (-1);
280 if (suffix == NULL)
281 return (-1);
282 if (filename_length < 1 + strlen(name) + 4 + 6 + 1 + strlen(suffix))
283 return (-1);
284 my_id = id;
285 sprintf(filename, "K%s+%03d+%05d.%s", name, alg, my_id,
286 (const char *) suffix);
287 if (strrchr(filename, '/'))
288 return (-1);
289 if (strrchr(filename, '\\'))
290 return (-1);
291 if (strrchr(filename, ':'))
292 return (-1);
293 return (0);
294 }
295
296 /*%
297 * dst_s_fopen ()
298 * Open a file in the dst_path directory. If perm is specified, the
299 * file is checked for existence first, and not opened if it exists.
300 * Parameters
301 * filename File to open
302 * mode Mode to open the file (passed directly to fopen)
303 * perm File permission, if creating a new file.
304 * Returns
305 * NULL Failure
306 * NON-NULL (FILE *) of opened file.
307 */
308 FILE *
dst_s_fopen(const char * filename,const char * mode,int perm)309 dst_s_fopen(const char *filename, const char *mode, int perm)
310 {
311 FILE *fp;
312 char pathname[PATH_MAX];
313
314 if (strlen(filename) + strlen(dst_path) >= sizeof(pathname))
315 return (NULL);
316
317 if (*dst_path != '\0') {
318 strcpy(pathname, dst_path);
319 strcat(pathname, filename);
320 } else
321 strcpy(pathname, filename);
322
323 fp = fopen(pathname, mode);
324 if (perm)
325 chmod(pathname, (mode_t)perm);
326 return (fp);
327 }
328
329 void
dst_s_dump(const int mode,const u_char * data,const int size,const char * msg)330 dst_s_dump(const int mode, const u_char *data, const int size,
331 const char *msg)
332 {
333 UNUSED(data);
334
335 if (size > 0) {
336 #ifdef LONG_TEST
337 static u_char scratch[1000];
338 int n ;
339 n = b64_ntop(data, scratch, size, sizeof(scratch));
340 printf("%s: %x %d %s\n", msg, mode, n, scratch);
341 #else
342 printf("%s,%x %d\n", msg, mode, size);
343 #endif
344 }
345 }
346
347 /*! \file */
348