xref: /netbsd/usr.sbin/tcpdchk/scaffold.c (revision bf9ec67e)
1 /*	$NetBSD: scaffold.c,v 1.7 1999/08/31 13:58:58 itojun Exp $	*/
2 
3  /*
4   * Routines for testing only. Not really industrial strength.
5   *
6   * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
7   */
8 
9 #include <sys/cdefs.h>
10 #ifndef lint
11 #if 0
12 static char sccs_id[] = "@(#) scaffold.c 1.6 97/03/21 19:27:24";
13 #else
14 __RCSID("$NetBSD: scaffold.c,v 1.7 1999/08/31 13:58:58 itojun Exp $");
15 #endif
16 #endif
17 
18 /* System libraries. */
19 
20 #include <sys/types.h>
21 #include <sys/stat.h>
22 #include <sys/socket.h>
23 #include <netinet/in.h>
24 #include <arpa/inet.h>
25 #include <netdb.h>
26 #include <stdio.h>
27 #include <syslog.h>
28 #include <setjmp.h>
29 #include <string.h>
30 #include <stdlib.h>
31 
32 #ifndef INADDR_NONE
33 #define	INADDR_NONE	(-1)		/* XXX should be 0xffffffff */
34 #endif
35 
36 /* Application-specific. */
37 
38 #include "tcpd.h"
39 #include "scaffold.h"
40 
41 static struct hostent *dup_hostent __P((struct hostent *));
42 
43  /*
44   * These are referenced by the options module and by rfc931.c.
45   */
46 int     allow_severity = SEVERITY;
47 int     deny_severity = LOG_WARNING;
48 extern int rfc931_timeout; /* = RFC931_TIMEOUT; */
49 
50 /* dup_hostent - create hostent in one memory block */
51 
52 static struct hostent *dup_hostent(hp)
53 struct hostent *hp;
54 {
55     struct hostent_block {
56 	struct hostent host;
57 	char   *addr_list[1];
58     };
59     struct hostent_block *hb;
60     int     count;
61     char   *data;
62     char   *addr;
63 
64     for (count = 0; hp->h_addr_list[count] != 0; count++)
65 	 /* void */ ;
66 
67     if ((hb = (struct hostent_block *) malloc(sizeof(struct hostent_block)
68 			 + (hp->h_length + sizeof(char *)) * count)) == 0) {
69 	fprintf(stderr, "Sorry, out of memory\n");
70 	exit(1);
71     }
72     memset((char *) &hb->host, 0, sizeof(hb->host));
73     hb->host.h_addrtype = hp->h_addrtype;
74     hb->host.h_length = hp->h_length;
75     hb->host.h_addr_list = hb->addr_list;
76     hb->host.h_addr_list[count] = 0;
77     data = (char *) (hb->host.h_addr_list + count + 1);
78 
79     for (count = 0; (addr = hp->h_addr_list[count]) != 0; count++) {
80 	hb->host.h_addr_list[count] = data + hp->h_length * count;
81 	memcpy(hb->host.h_addr_list[count], addr, hp->h_length);
82     }
83     return (&hb->host);
84 }
85 
86 /* find_inet_addr - find all addresses for this host, result to free() */
87 
88 struct hostent *find_inet_addr(host)
89 char   *host;
90 {
91     struct in_addr addr;
92     unsigned long addr_num;
93     struct hostent *hp;
94     static struct hostent h;
95     static char *addr_list[2];
96 #ifdef INET6
97     static struct in6_addr in6;
98 #endif
99 
100     /*
101      * Host address: translate it to internal form.
102      */
103     if (dot_quad_addr(host, &addr_num) == 0) {
104 	addr.s_addr = (addr_num & 0xffffffff);
105 	h.h_addr_list = addr_list;
106 	h.h_addr_list[0] = (char *) &addr;
107 	h.h_length = sizeof(addr);
108 	h.h_addrtype = AF_INET;
109 	return (dup_hostent(&h));
110     }
111 #ifdef INET6
112     if (inet_pton(AF_INET6, host, &in6) == 1) {
113 	h.h_addr_list = addr_list;
114 	h.h_addr_list[0] = (char *) &in6;
115 	h.h_length = sizeof(in6);
116 	h.h_addrtype = AF_INET6;
117 	return (dup_hostent(&h));
118     }
119 #endif
120 
121     /*
122      * Map host name to a series of addresses. Watch out for non-internet
123      * forms or aliases. The NOT_INADDR() is here in case gethostbyname() has
124      * been "enhanced" to accept numeric addresses. Make a copy of the
125      * address list so that later gethostbyXXX() calls will not clobber it.
126      */
127 #ifdef INET6
128     if (NOT_INADDR(host) == 0 && inet_pton(AF_INET6, host, &in6) == 1)
129 #else
130     if (NOT_INADDR(host) == 0)
131 #endif
132     {
133 	tcpd_warn("%s: not an internet address", host);
134 	return (0);
135     }
136 #ifdef INET6
137     /*
138      * XXX this behavior may, or may not be desirable.
139      * - we may better use getipnodebyname() to addresses of get both AFs,
140      *   however, getipnodebyname() is not widely implemented.
141      * - it may be better to have a way to specify the AF to use.
142      */
143     if ((hp = gethostbyname2(host, AF_INET)) == 0
144      && (hp = gethostbyname2(host, AF_INET6)) == 0) {
145 	tcpd_warn("%s: host not found", host);
146 	return (0);
147     }
148 #else
149     if ((hp = gethostbyname(host)) == 0) {
150 	tcpd_warn("%s: host not found", host);
151 	return (0);
152     }
153     if (hp->h_addrtype != AF_INET) {
154 	tcpd_warn("%d: not an internet host", hp->h_addrtype);
155 	return (0);
156     }
157 #endif
158     if (STR_NE(host, hp->h_name)) {
159 	tcpd_warn("%s: hostname alias", host);
160 	tcpd_warn("(official name: %.*s)", STRING_LENGTH, hp->h_name);
161     }
162     return (dup_hostent(hp));
163 }
164 
165 /* check_dns - give each address thorough workout, return address count */
166 
167 int     check_dns(host)
168 char   *host;
169 {
170     struct request_info request;
171     struct sockaddr_storage sin;
172     struct hostent *hp;
173     int     count;
174     char   *addr;
175     char *ap;
176     int alen;
177 
178     if ((hp = find_inet_addr(host)) == 0)
179 	return (0);
180     request_init(&request, RQ_CLIENT_SIN, &sin, 0);
181     sock_methods(&request);
182     memset((char *) &sin, 0, sizeof(sin));
183     sin.ss_family = hp->h_addrtype;
184     switch (hp->h_addrtype) {
185     case AF_INET:
186 	ap = (char *)&((struct sockaddr_in *)&sin)->sin_addr;
187 	alen = sizeof(struct in6_addr);
188 	break;
189 #ifdef INET6
190     case AF_INET6:
191 	ap = (char *)&((struct sockaddr_in6 *)&sin)->sin6_addr;
192 	alen = sizeof(struct in6_addr);
193 	break;
194 #endif
195     default:
196 	return (0);
197     }
198 
199     for (count = 0; (addr = hp->h_addr_list[count]) != 0; count++) {
200 	memcpy(ap, addr, alen);
201 
202 	/*
203 	 * Force host name and address conversions. Use the request structure
204 	 * as a cache. Detect hostname lookup problems. Any name/name or
205 	 * name/address conflicts will be reported while eval_hostname() does
206 	 * its job.
207 	 */
208 	request_set(&request, RQ_CLIENT_ADDR, "", RQ_CLIENT_NAME, "", 0);
209 	if (STR_EQ(eval_hostname(request.client), unknown))
210 	    tcpd_warn("host address %s->name lookup failed",
211 		      eval_hostaddr(request.client));
212     }
213     free((char *) hp);
214     return (count);
215 }
216 
217 /* dummy function to intercept the real shell_cmd() */
218 
219 /* ARGSUSED */
220 
221 void    shell_cmd(command)
222 char   *command;
223 {
224     if (hosts_access_verbose)
225 	printf("command: %s", command);
226 }
227 
228 /* dummy function  to intercept the real clean_exit() */
229 
230 /* ARGSUSED */
231 
232 void    clean_exit(request)
233 struct request_info *request;
234 {
235     exit(0);
236 }
237 
238 #if 0
239 /* dummy function  to intercept the real rfc931() */
240 
241 /* ARGSUSED */
242 
243 void    rfc931(request)
244 struct request_info *request;
245 {
246     strcpy(request->user, unknown);
247 }
248 #endif
249 
250 /* check_path - examine accessibility */
251 
252 int     check_path(path, st)
253 char   *path;
254 struct stat *st;
255 {
256     struct stat stbuf;
257     char    buf[BUFSIZ];
258 
259     if (stat(path, st) < 0)
260 	return (-1);
261 #ifdef notdef
262     if (st->st_uid != 0)
263 	tcpd_warn("%s: not owned by root", path);
264     if (st->st_mode & 020)
265 	tcpd_warn("%s: group writable", path);
266 #endif
267     if (st->st_mode & 002)
268 	tcpd_warn("%s: world writable", path);
269     if (path[0] == '/' && path[1] != 0) {
270 	strrchr(strcpy(buf, path), '/')[0] = 0;
271 	(void) check_path(buf[0] ? buf : "/", &stbuf);
272     }
273     return (0);
274 }
275