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