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