Commit | Line | Data |
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aa424df8 | 1 | /*- |
6ad0a189 | 2 | * Copyright (c) 1985, 1989 Regents of the University of California. |
6b2f9dd0 KB |
3 | * All rights reserved. |
4 | * | |
aa424df8 | 5 | * %sccs.include.redist.c% |
b423e985 RC |
6 | */ |
7 | ||
2ce81398 | 8 | #if defined(LIBC_SCCS) && !defined(lint) |
24fac7d8 | 9 | static char sccsid[] = "@(#)res_init.c 6.15 (Berkeley) %G%"; |
6b2f9dd0 | 10 | #endif /* LIBC_SCCS and not lint */ |
8ea4199d | 11 | |
24fac7d8 | 12 | #include <sys/param.h> |
b53e7108 RC |
13 | #include <sys/socket.h> |
14 | #include <netinet/in.h> | |
24fac7d8 | 15 | #include <arpa/inet.h> |
56d853b7 | 16 | #include <arpa/nameser.h> |
a36af7fe | 17 | #include <resolv.h> |
24fac7d8 KB |
18 | #include <unistd.h> |
19 | #include <stdio.h> | |
20 | #include <stdlib.h> | |
21 | #include <string.h> | |
b53e7108 RC |
22 | |
23 | /* | |
24 | * Resolver state default settings | |
25 | */ | |
dc795f66 | 26 | |
b53e7108 | 27 | struct state _res = { |
6ad0a189 MK |
28 | RES_TIMEOUT, /* retransmition time interval */ |
29 | 4, /* number of times to retransmit */ | |
30 | RES_DEFAULT, /* options flags */ | |
31 | 1, /* number of name servers */ | |
b53e7108 RC |
32 | }; |
33 | ||
34 | /* | |
98959623 JB |
35 | * Set up default settings. If the configuration file exist, the values |
36 | * there will have precedence. Otherwise, the server address is set to | |
37 | * INADDR_ANY and the default domain name comes from the gethostname(). | |
38 | * | |
39 | * The configuration file should only be used if you want to redefine your | |
40 | * domain or run without a server on your machine. | |
41 | * | |
42 | * Return 0 if completes successfully, -1 on error | |
b53e7108 RC |
43 | */ |
44 | res_init() | |
45 | { | |
6ad0a189 MK |
46 | register FILE *fp; |
47 | register char *cp, **pp; | |
48 | register int n; | |
49 | char buf[BUFSIZ]; | |
6ad0a189 | 50 | int nserv = 0; /* number of nameserver records read from file */ |
05f93cda | 51 | int haveenv = 0; |
6ad0a189 | 52 | int havesearch = 0; |
b53e7108 | 53 | |
6ad0a189 MK |
54 | _res.nsaddr.sin_addr.s_addr = INADDR_ANY; |
55 | _res.nsaddr.sin_family = AF_INET; | |
56 | _res.nsaddr.sin_port = htons(NAMESERVER_PORT); | |
57 | _res.nscount = 1; | |
b53e7108 | 58 | |
6ad0a189 | 59 | /* Allow user to override the local domain definition */ |
05f93cda | 60 | if ((cp = getenv("LOCALDOMAIN")) != NULL) { |
6ad0a189 | 61 | (void)strncpy(_res.defdname, cp, sizeof(_res.defdname)); |
05f93cda MK |
62 | haveenv++; |
63 | } | |
b53e7108 | 64 | |
6ad0a189 MK |
65 | if ((fp = fopen(_PATH_RESCONF, "r")) != NULL) { |
66 | /* read the config file */ | |
67 | while (fgets(buf, sizeof(buf), fp) != NULL) { | |
68 | /* read default domain name */ | |
69 | if (!strncmp(buf, "domain", sizeof("domain") - 1)) { | |
05f93cda | 70 | if (haveenv) /* skip if have from environ */ |
6ad0a189 MK |
71 | continue; |
72 | cp = buf + sizeof("domain") - 1; | |
73 | while (*cp == ' ' || *cp == '\t') | |
74 | cp++; | |
faad658c | 75 | if ((*cp == '\0') || (*cp == '\n')) |
6ad0a189 MK |
76 | continue; |
77 | (void)strncpy(_res.defdname, cp, sizeof(_res.defdname) - 1); | |
78 | if ((cp = index(_res.defdname, '\n')) != NULL) | |
79 | *cp = '\0'; | |
80 | havesearch = 0; | |
81 | continue; | |
82 | } | |
83 | /* set search list */ | |
84 | if (!strncmp(buf, "search", sizeof("search") - 1)) { | |
05f93cda MK |
85 | if (haveenv) /* skip if have from environ */ |
86 | continue; | |
6ad0a189 MK |
87 | cp = buf + sizeof("search") - 1; |
88 | while (*cp == ' ' || *cp == '\t') | |
89 | cp++; | |
faad658c | 90 | if ((*cp == '\0') || (*cp == '\n')) |
6ad0a189 MK |
91 | continue; |
92 | (void)strncpy(_res.defdname, cp, sizeof(_res.defdname) - 1); | |
93 | if ((cp = index(_res.defdname, '\n')) != NULL) | |
94 | *cp = '\0'; | |
95 | /* | |
96 | * Set search list to be blank-separated strings | |
97 | * on rest of line. | |
98 | */ | |
99 | cp = _res.defdname; | |
100 | pp = _res.dnsrch; | |
101 | *pp++ = cp; | |
102 | for (n = 0; *cp && pp < _res.dnsrch + MAXDNSRCH; cp++) { | |
103 | if (*cp == ' ' || *cp == '\t') { | |
104 | *cp = 0; | |
105 | n = 1; | |
106 | } else if (n) { | |
107 | *pp++ = cp; | |
108 | n = 0; | |
109 | } | |
110 | } | |
aa424df8 JB |
111 | /* null terminate last domain if there are excess */ |
112 | while (*cp != '\0' && *cp != ' ' && *cp != '\t') | |
113 | cp++; | |
114 | *cp = '\0'; | |
05f93cda | 115 | *pp++ = 0; |
6ad0a189 MK |
116 | havesearch = 1; |
117 | continue; | |
118 | } | |
119 | /* read nameservers to query */ | |
120 | if (!strncmp(buf, "nameserver", sizeof("nameserver") - 1) && | |
121 | nserv < MAXNS) { | |
122 | cp = buf + sizeof("nameserver") - 1; | |
123 | while (*cp == ' ' || *cp == '\t') | |
124 | cp++; | |
faad658c | 125 | if ((*cp == '\0') || (*cp == '\n')) |
6ad0a189 MK |
126 | continue; |
127 | if ((_res.nsaddr_list[nserv].sin_addr.s_addr = | |
f06fd99d JB |
128 | inet_addr(cp)) == (unsigned)-1) { |
129 | _res.nsaddr_list[nserv].sin_addr.s_addr | |
130 | = INADDR_ANY; | |
6ad0a189 | 131 | continue; |
f06fd99d | 132 | } |
6ad0a189 MK |
133 | _res.nsaddr_list[nserv].sin_family = AF_INET; |
134 | _res.nsaddr_list[nserv].sin_port = htons(NAMESERVER_PORT); | |
135 | nserv++; | |
136 | continue; | |
137 | } | |
138 | } | |
139 | if (nserv > 1) | |
140 | _res.nscount = nserv; | |
141 | (void) fclose(fp); | |
142 | } | |
143 | if (_res.defdname[0] == 0) { | |
144 | if (gethostname(buf, sizeof(_res.defdname)) == 0 && | |
145 | (cp = index(buf, '.'))) | |
146 | (void)strcpy(_res.defdname, cp + 1); | |
147 | } | |
a6c365b5 | 148 | |
6ad0a189 MK |
149 | /* find components of local domain that might be searched */ |
150 | if (havesearch == 0) { | |
151 | pp = _res.dnsrch; | |
152 | *pp++ = _res.defdname; | |
153 | for (cp = _res.defdname, n = 0; *cp; cp++) | |
154 | if (*cp == '.') | |
155 | n++; | |
156 | cp = _res.defdname; | |
05f93cda | 157 | for (; n >= LOCALDOMAINPARTS && pp < _res.dnsrch + MAXDFLSRCH; |
6ad0a189 MK |
158 | n--) { |
159 | cp = index(cp, '.'); | |
160 | *pp++ = ++cp; | |
161 | } | |
05f93cda | 162 | *pp++ = 0; |
6ad0a189 MK |
163 | } |
164 | _res.options |= RES_INIT; | |
165 | return (0); | |
b53e7108 | 166 | } |