1 /*
2 * Copyright 2001 Sun Microsystems, Inc. All rights reserved.
3 * Use is subject to license terms.
4 */
5 #pragma ident "%Z%%M% %I% %E% SMI"
6
7 /*
8 * Misc routines that are used by tcpd and by tcpdchk.
9 *
10 * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
11 */
12
13 #ifndef lint
14 static char sccsic[] = "@(#) misc.c 1.2 96/02/11 17:01:29";
15 #endif
16
17 #include <sys/types.h>
18 #include <sys/param.h>
19 #include <netinet/in.h>
20 #include <arpa/inet.h>
21 #include <stdio.h>
22 #include <string.h>
23 #include <ctype.h>
24 #include <netdb.h>
25
26 #include "tcpd.h"
27
28 extern char *fgets();
29
30 #ifndef INADDR_NONE
31 #define INADDR_NONE (-1) /* XXX should be 0xffffffff */
32 #endif
33
34 /* xgets - fgets() with backslash-newline stripping */
35
xgets(ptr,len,fp)36 char *xgets(ptr, len, fp)
37 char *ptr;
38 int len;
39 FILE *fp;
40 {
41 int got;
42 char *start = ptr;
43
44 while (fgets(ptr, len, fp)) {
45 got = strlen(ptr);
46 if (got >= 1 && ptr[got - 1] == '\n') {
47 tcpd_context.line++;
48 if (got >= 2 && ptr[got - 2] == '\\') {
49 got -= 2;
50 } else {
51 return (start);
52 }
53 }
54 ptr += got;
55 len -= got;
56 ptr[0] = 0;
57 }
58 return (ptr > start ? start : 0);
59 }
60
61 /* split_at - break string at delimiter or return NULL */
62
split_at(string,delimiter)63 char *split_at(string, delimiter)
64 char *string;
65 int delimiter;
66 {
67 char *cp;
68
69 if ((cp = strchr(string, delimiter)) != 0)
70 *cp++ = 0;
71 return (cp);
72 }
73
74 /* dot_quad_addr - convert dotted quad to internal form */
75
dot_quad_addr(str)76 unsigned long dot_quad_addr(str)
77 char *str;
78 {
79 int in_run = 0;
80 int runs = 0;
81 char *cp = str;
82
83 /* Count the number of runs of non-dot characters. */
84
85 while (*cp) {
86 if (*cp == '.') {
87 in_run = 0;
88 } else if (in_run == 0) {
89 in_run = 1;
90 runs++;
91 }
92 cp++;
93 }
94 return (runs == 4 ? inet_addr(str) : INADDR_NONE);
95 }
96
97 /* numeric_addr - convert textual IP address to binary form */
98
numeric_addr(str,addr,af,len)99 int numeric_addr(str, addr, af, len)
100 char *str;
101 union gen_addr *addr;
102 int *af;
103 int *len;
104 {
105 union gen_addr t;
106
107 if (addr == NULL)
108 addr = &t;
109 #ifdef HAVE_IPV6
110 if (strchr(str,':')) {
111 if (af) *af = AF_INET6;
112 if (len) *len = sizeof(struct in6_addr);
113 if (inet_pton(AF_INET6, str, (void*) addr) == 1)
114 return 0;
115 return -1;
116 }
117 #endif
118 if (af) *af = AF_INET;
119 if (len) *len = sizeof(struct in_addr);
120 addr->ga_in.s_addr = dot_quad_addr(str);
121 return addr->ga_in.s_addr == INADDR_NONE ? -1 : 0;
122 }
123
124 /* For none RFC 2553 compliant systems */
125 #ifdef USE_GETHOSTBYNAME2
126 #define getipnodebyname(h,af,flags,err) gethostbyname2(h,af)
127 #define freehostent(x) x = 0
128 #endif
129
130 /* tcpd_gethostbyname - an IP family neutral gethostbyname */
131
tcpd_gethostbyname(host,af)132 struct hostent *tcpd_gethostbyname(host, af)
133 char *host;
134 int af;
135 {
136 #ifdef HAVE_IPV6
137 struct hostent *hp;
138 static struct hostent *hs; /* freehostent() on next call */
139 int err;
140
141 if (af == AF_INET6) { /* must be AF_INET6 */
142 if (hs)
143 freehostent(hs);
144 return (hs = getipnodebyname(host, AF_INET6, 0, &err));
145 }
146 hp = gethostbyname(host);
147 if (hp != NULL || af == AF_INET) { /* found or must be AF_INET */
148 return hp;
149 } else { /* Try INET6 */
150 if (hs)
151 freehostent(hs);
152 return (hs = getipnodebyname(host, AF_INET6, 0, &err));
153 }
154 #else
155 return gethostbyname(host);
156 #endif
157 }
158
159 #ifdef HAVE_IPV6
160 /*
161 * When using IPv6 addresses, we'll be seeing lots of ":"s;
162 * we require the addresses to be specified as [address].
163 * An IPv6 address can be specified in 3 ways:
164 *
165 * x:x:x:x:x:x:x:x (fully specified)
166 * x::x:x:x:x (zeroes squashed)
167 * ::FFFF:1.2.3.4 (IPv4 mapped)
168 *
169 * These need to be skipped to get at the ":" delimeters.
170 *
171 * We also allow a '/prefix' specifier.
172 */
skip_ipv6_addrs(str)173 char *skip_ipv6_addrs(str)
174 char *str;
175 {
176 char *obr, *cbr, *colon;
177 char *p = str;
178 char *q;
179
180 while (1) {
181 if ((colon = strchr(p, ':')) == NULL)
182 return p;
183 if ((obr = strchr(p, '[')) == NULL || obr > colon)
184 return p;
185 if ((cbr = strchr(obr, ']')) == NULL)
186 return p;
187
188 for (q = obr + 1; q < cbr; q++) {
189 /*
190 * Quick and dirty parse, cheaper than inet_pton
191 * Could count colons and dots (must be 0 or 3 dots, no
192 * colons after dots seens, only one double :, etc, etc)
193 */
194 if (*q != ':' && *q != '.' && *q != '/' && !isxdigit(*q & 0xff))
195 return p;
196 }
197 p = cbr + 1;
198 }
199 }
200 #endif /* HAVE_IPV6 */
201