1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License"). You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22 /*
23 * Copyright 2002-2003 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
25 */
26
27 #pragma ident "%Z%%M% %I% %E% SMI"
28
29 #include <sys/salib.h>
30 #include <sys/types.h>
31 #include <sys/socket.h>
32 #include <sys/bootvfs.h>
33 #include <netinet/in.h>
34
35 /*
36 * This structure defines the static area where gethostbyname()
37 * stores the hostent data that it returns to the caller.
38 */
39 static struct {
40 struct hostent he;
41 in_addr_t *ha_list[2];
42 in_addr_t ha_addr;
43 char ha_name[MAXHOSTNAMELEN+1];
44 } hostinfo;
45
46 int h_errno;
47
48 static in_addr_t inet_addr(const char *);
49 static in_addr_t nam2addr(const char *);
50
51 /* Very stripped-down gethostbyname() */
52 struct hostent *
53 gethostbyname(const char *nam)
54 {
55 bzero(&hostinfo, sizeof (hostinfo));
56
57 hostinfo.ha_addr = inet_addr(nam);
58 if ((int32_t)hostinfo.ha_addr == -1) {
59 if (get_default_fs() == NULL) {
60 h_errno = HOST_NOT_FOUND;
61 return (NULL);
62 }
63 hostinfo.ha_addr = nam2addr(nam);
64 if ((int32_t)hostinfo.ha_addr == -1) {
65 h_errno = HOST_NOT_FOUND;
66 return (NULL);
67 }
68 }
69
70 hostinfo.he.h_addrtype = AF_INET;
71 (void) strlcpy(hostinfo.ha_name, nam, MAXHOSTNAMELEN);
72 hostinfo.he.h_name = hostinfo.ha_name;
73 hostinfo.he.h_length = sizeof (struct in_addr);
74 hostinfo.ha_list[0] = &hostinfo.ha_addr;
75 hostinfo.he.h_addr_list = (char **)&hostinfo.ha_list;
76 return (&hostinfo.he);
77 }
78
79 #define SKIP_SPACE(_p) \
80 { \
81 char _c; \
82 while ((_c = *(_p)) != '\0' && isspace(_c)) \
83 p++; \
84 if (_c == '\0') \
85 goto next_line; \
86 }
87
88 #define SKIP_TOKEN(_p) \
89 { \
90 char _c; \
91 while ((_c = *(_p)) != '\0' && !isspace(_c)) \
92 p++; \
93 if (_c == '\0') \
94 goto next_line; \
95 }
96
97 #define TRIM_LINE(_l) \
98 { \
99 char _c, *_p = (_l); \
100 while ((_c = *_p) != '#' && _c != '\n' && _c != '\0') \
101 _p++; \
102 *_p = '\0'; \
103 }
104
105 #define BUFSZ 1024
106 #define HOSTDB "/etc/inet/hosts"
107
108 static in_addr_t
109 nam2addr(const char *nam)
110 {
111 FILE *h;
112 char c, buf[BUFSZ];
113 char *l, *p, *s;
114 boolean_t first_token;
115
116 if ((h = fopen(HOSTDB, "r")) == NULL) {
117 return ((in_addr_t)-1);
118 }
119
120 next_line:
121 if ((l = fgets(buf, BUFSZ, h)) == NULL) {
122 (void) fclose(h);
123 return ((in_addr_t)-1);
124 }
125 TRIM_LINE(l);
126
127 p = l;
128 first_token = B_TRUE;
129 next_token:
130 SKIP_SPACE(p);
131
132 if (first_token) {
133 first_token = B_FALSE;
134 SKIP_TOKEN(p);
135
136 *p++ = '\0';
137 goto next_token;
138 }
139
140 s = (char *)nam;
141 if (*p++ == *s++) {
142 while ((c = *s++) == *p && c != '\0')
143 p++;
144 if (c == '\0' && (isspace(*p) || *p == '\0'))
145 goto match;
146 }
147
148 SKIP_TOKEN(p);
149 goto next_token;
150 match:
151 (void) fclose(h);
152 return (inet_addr((const char *)l));
153 }
154
155 static in_addr_t
156 inet_addr(const char *cp)
157 {
158 in_addr_t val;
159 uint_t base, n;
160 char c;
161 in_addr_t parts[4], *pp = parts;
162
163 again:
164 /*
165 * Collect number up to ``.''.
166 * Values are specified as for C:
167 * 0x=hex, 0=octal, other=decimal.
168 */
169 val = 0; base = 10;
170 if (*cp == '0') {
171 if (*++cp == 'x' || *cp == 'X')
172 base = 16, cp++;
173 else
174 base = 8;
175 }
176
177 while ((c = *cp) != 0) {
178 if (isdigit(c)) {
179 if ((c - '0') >= base)
180 break;
181 val = (val * base) + (c - '0');
182 cp++;
183 continue;
184 }
185 if (base == 16 && isxdigit(c)) {
186 val = (val << 4) + (c + 10 - (islower(c) ? 'a' : 'A'));
187 cp++;
188 continue;
189 }
190 break;
191 }
192 if (*cp == '.') {
193 /*
194 * Internet format:
195 * a.b.c.d
196 * a.b.c (with c treated as 16-bits)
197 * a.b (with b treated as 24 bits)
198 */
199 if (pp >= parts + 4)
200 return ((in_addr_t)-1);
201 *pp++ = val, cp++;
202 goto again;
203 }
204 /*
205 * Check for trailing characters.
206 */
207 if (*cp && !isspace(*cp))
208 return ((in_addr_t)-1);
209 *pp++ = val;
210 /*
211 * Concoct the address according to
212 * the number of parts specified.
213 */
214 n = pp - parts;
215 switch (n) {
216
217 case 1: /* a -- 32 bits */
218 val = parts[0];
219 break;
220
221 case 2: /* a.b -- 8.24 bits */
222 val = (parts[0] << 24) | (parts[1] & 0xffffff);
223 break;
224
225 case 3: /* a.b.c -- 8.8.16 bits */
226 val = (parts[0] << 24) | ((parts[1] & 0xff) << 16) |
227 (parts[2] & 0xffff);
228 break;
229
230 case 4: /* a.b.c.d -- 8.8.8.8 bits */
231 val = (parts[0] << 24) | ((parts[1] & 0xff) << 16) |
232 ((parts[2] & 0xff) << 8) | (parts[3] & 0xff);
233 break;
234
235 default:
236 return ((in_addr_t)-1);
237 }
238 val = htonl(val);
239 return (val);
240 }