scaffold.c revision 56977 
1 /*
2  * Routines for testing only. Not really industrial strength.
3  *
4  * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
5  *
6  * $FreeBSD: head/contrib/tcp_wrappers/scaffold.c 56977 2000-02-03 10:27:03Z shin $
7  */
8
9#ifndef lint
10static char sccs_id[] = "@(#) scaffold.c 1.6 97/03/21 19:27:24";
11#endif
12
13/* System libraries. */
14
15#include <sys/types.h>
16#include <sys/stat.h>
17#include <sys/socket.h>
18#include <netinet/in.h>
19#include <arpa/inet.h>
20#include <netdb.h>
21#include <stdio.h>
22#include <syslog.h>
23#include <setjmp.h>
24#include <string.h>
25#include <resolv.h>
26
27#ifndef INADDR_NONE
28#define	INADDR_NONE	(-1)		/* XXX should be 0xffffffff */
29#endif
30
31extern char *malloc();
32
33/* Application-specific. */
34
35#include "tcpd.h"
36#include "scaffold.h"
37
38 /*
39  * These are referenced by the options module and by rfc931.c.
40  */
41int     allow_severity = SEVERITY;
42int     deny_severity = LOG_WARNING;
43int     rfc931_timeout = RFC931_TIMEOUT;
44
45/* dup_hostent - create hostent in one memory block */
46
47static struct hostent *dup_hostent(hp)
48struct hostent *hp;
49{
50    struct hostent_block {
51	struct hostent host;
52	char   *addr_list[1];
53    };
54    struct hostent_block *hb;
55    int     count;
56    char   *data;
57    char   *addr;
58
59    for (count = 0; hp->h_addr_list[count] != 0; count++)
60	 /* void */ ;
61
62    if ((hb = (struct hostent_block *) malloc(sizeof(struct hostent_block)
63#ifdef INET6
64			 + strlen(hp->h_name) + 1
65#endif
66			 + (hp->h_length + sizeof(char *)) * count)) == 0) {
67	fprintf(stderr, "Sorry, out of memory\n");
68	exit(1);
69    }
70    memset((char *) &hb->host, 0, sizeof(hb->host));
71    hb->host.h_length = hp->h_length;
72    hb->host.h_addr_list = hb->addr_list;
73    hb->host.h_addr_list[count] = 0;
74    data = (char *) (hb->host.h_addr_list + count + 1);
75#ifdef INET6
76    hb->host.h_name = data + hp->h_length * count;
77    strcpy(hb->host.h_name, hp->h_name);
78    hb->host.h_addrtype = hp->h_addrtype;
79#endif
80
81    for (count = 0; (addr = hp->h_addr_list[count]) != 0; count++) {
82	hb->host.h_addr_list[count] = data + hp->h_length * count;
83	memcpy(hb->host.h_addr_list[count], addr, hp->h_length);
84    }
85    return (&hb->host);
86}
87
88#if defined(INET6) && !defined(USE_GETIPNODEBY)
89/* merge_hostent - merge hostent in one memory block */
90
91static struct hostent *merge_hostent(hp1, hp2)
92struct hostent *hp1, *hp2;
93{
94    struct hostent_block {
95	struct hostent host;
96	char   *addr_list[1];
97    };
98    struct hostent_block *hb;
99    int     count, count2;
100    char   *data;
101    char   *addr;
102
103    for (count = 0; hp1->h_addr_list[count] != 0; count++)
104	 /* void */ ;
105    for (count2 = 0; hp2->h_addr_list[count2] != 0; count2++)
106	 /* void */ ;
107    count += count2;
108
109    if ((hb = (struct hostent_block *) malloc(sizeof(struct hostent_block)
110			 + strlen(hp1->h_name) + 1
111			 + (hp1->h_length + sizeof(char *)) * count)) == 0) {
112	fprintf(stderr, "Sorry, out of memory\n");
113	exit(1);
114    }
115    memset((char *) &hb->host, 0, sizeof(hb->host));
116    hb->host.h_length = hp1->h_length;
117    hb->host.h_addr_list = hb->addr_list;
118    hb->host.h_addr_list[count] = 0;
119    data = (char *) (hb->host.h_addr_list + count + 1);
120    hb->host.h_name = data + hp1->h_length * count;
121    strcpy(hb->host.h_name, hp1->h_name);
122    hb->host.h_addrtype = hp1->h_addrtype;
123
124    for (count = 0; (addr = hp1->h_addr_list[count]) != 0; count++) {
125	hb->host.h_addr_list[count] = data + hp1->h_length * count;
126	memcpy(hb->host.h_addr_list[count], addr, hp1->h_length);
127    }
128    for (count2 = 0; (addr = hp2->h_addr_list[count2]) != 0; count2++) {
129	hb->host.h_addr_list[count] = data + hp1->h_length * count;
130	memcpy(hb->host.h_addr_list[count], addr, hp1->h_length);
131	++count;
132    }
133    return (&hb->host);
134}
135#endif
136
137static struct hostent *gethostbyname64(host)
138char *host;
139{
140    struct hostent *hp = NULL, *hp2 = NULL;
141#ifdef USE_GETIPNODEBY
142    int h_error;
143
144    if ((hp = getipnodebyname(host, AF_INET6,
145			      AI_V4MAPPED | AI_ADDRCONFIG | AI_ALL,
146			      &h_error)) != 0) {
147	hp2 = dup_hostent(hp);
148	freehostent(hp);
149	return (hp2);
150    }
151#else
152    struct hostent *hp1;
153    u_long res_options;
154
155    if ((_res.options & RES_INIT) == 0) {
156	if (res_init() < 0) {
157	    tcpd_warn("%s: res_init() failed", host);
158	    return (NULL);
159	}
160    }
161    res_options = _res.options;
162#ifdef INET6
163    _res.options |= RES_USE_INET6;
164    if ((hp1 = gethostbyname2(host, AF_INET6)) != NULL)
165	hp1 = dup_hostent(hp1);
166#endif
167    if ((hp2 = gethostbyname2(host, AF_INET)) != NULL)
168	hp2 = dup_hostent(hp2);
169    _res.options = res_options;
170#ifdef INET6
171    if (hp1 && hp2) {
172	hp = merge_hostent(hp1, hp2);
173	free((char *) hp1);
174	free((char *) hp2);
175	return (hp);
176    }
177    if (hp1)
178	return (hp1);
179#endif
180    if (hp2)
181	return (hp2);
182#endif
183    return (NULL);
184}
185
186/* find_inet_addr - find all addresses for this host, result to free() */
187
188struct hostent *find_inet_addr(host)
189char   *host;
190{
191    struct in_addr addr;
192    struct hostent *hp;
193    static struct hostent h;
194    static char *addr_list[2];
195    static char hnamebuf[BUFSIZ];
196
197    /*
198     * Host address: translate it to internal form.
199     */
200    if ((addr.s_addr = dot_quad_addr(host)) != INADDR_NONE) {
201	h.h_addr_list = addr_list;
202	h.h_addr_list[0] = (char *) &addr;
203	h.h_length = sizeof(addr);
204#ifdef INET6
205	h.h_addrtype = AF_INET;
206	h.h_name = hnamebuf;
207	strcpy(h.h_name, host);
208#endif
209	return (dup_hostent(&h));
210    }
211
212    /*
213     * Map host name to a series of addresses. Watch out for non-internet
214     * forms or aliases. The NOT_INADDR() is here in case gethostbyname() has
215     * been "enhanced" to accept numeric addresses. Make a copy of the
216     * address list so that later gethostbyXXX() calls will not clobber it.
217     */
218    if (NOT_INADDR(host) == 0) {
219	tcpd_warn("%s: not an internet address", host);
220	return (0);
221    }
222#ifdef INET6
223    if ((hp = gethostbyname64(host)) == 0) {
224#else
225    if ((hp = gethostbyname(host)) == 0) {
226#endif
227	tcpd_warn("%s: host not found", host);
228	return (0);
229    }
230#ifdef INET6
231    if (hp->h_addrtype != AF_INET6) {
232	tcpd_warn("%d: not an internet host", hp->h_addrtype);
233	free((char *) hp);
234#else
235    if (hp->h_addrtype != AF_INET) {
236	tcpd_warn("%d: not an internet host", hp->h_addrtype);
237#endif
238	return (0);
239    }
240    if (STR_NE(host, hp->h_name)) {
241	tcpd_warn("%s: hostname alias", host);
242	tcpd_warn("(official name: %.*s)", STRING_LENGTH, hp->h_name);
243    }
244#ifdef INET6
245    return (hp);
246#else
247    return (dup_hostent(hp));
248#endif
249}
250
251/* check_dns - give each address thorough workout, return address count */
252
253int     check_dns(host)
254char   *host;
255{
256    struct request_info request;
257#ifdef INET6
258    struct sockaddr_storage sin;
259    char *ap;
260    int alen;
261#else
262    struct sockaddr_in sin;
263#endif
264    struct hostent *hp;
265    int     count;
266    char   *addr;
267
268    if ((hp = find_inet_addr(host)) == 0)
269	return (0);
270    request_init(&request, RQ_CLIENT_SIN, &sin, 0);
271    sock_methods(&request);
272    memset((char *) &sin, 0, sizeof(sin));
273#ifdef INET6
274    sin.ss_family = hp->h_addrtype;
275    switch (hp->h_addrtype) {
276    case AF_INET:
277	ap = (char *)&((struct sockaddr_in *)&sin)->sin_addr;
278	alen = sizeof(struct sockaddr_in);
279	break;
280    case AF_INET6:
281	ap = (char *)&((struct sockaddr_in6 *)&sin)->sin6_addr;
282	alen = sizeof(struct sockaddr_in6);
283	break;
284    default:
285	return (0);
286    }
287#else
288    sin.sin_family = AF_INET;
289#endif
290
291    for (count = 0; (addr = hp->h_addr_list[count]) != 0; count++) {
292#ifdef INET6
293	memcpy(ap, addr, alen);
294#else
295	memcpy((char *) &sin.sin_addr, addr, sizeof(sin.sin_addr));
296#endif
297
298	/*
299	 * Force host name and address conversions. Use the request structure
300	 * as a cache. Detect hostname lookup problems. Any name/name or
301	 * name/address conflicts will be reported while eval_hostname() does
302	 * its job.
303	 */
304	request_set(&request, RQ_CLIENT_ADDR, "", RQ_CLIENT_NAME, "", 0);
305	if (STR_EQ(eval_hostname(request.client), unknown))
306	    tcpd_warn("host address %s->name lookup failed",
307		      eval_hostaddr(request.client));
308    }
309    free((char *) hp);
310    return (count);
311}
312
313/* dummy function to intercept the real shell_cmd() */
314
315/* ARGSUSED */
316
317void    shell_cmd(command)
318char   *command;
319{
320    if (hosts_access_verbose)
321	printf("command: %s", command);
322}
323
324/* dummy function  to intercept the real clean_exit() */
325
326/* ARGSUSED */
327
328void    clean_exit(request)
329struct request_info *request;
330{
331    exit(0);
332}
333
334/* dummy function  to intercept the real rfc931() */
335
336/* ARGSUSED */
337
338void    rfc931(request)
339struct request_info *request;
340{
341    strcpy(request->user, unknown);
342}
343
344/* check_path - examine accessibility */
345
346int     check_path(path, st)
347char   *path;
348struct stat *st;
349{
350    struct stat stbuf;
351    char    buf[BUFSIZ];
352
353    if (stat(path, st) < 0)
354	return (-1);
355#ifdef notdef
356    if (st->st_uid != 0)
357	tcpd_warn("%s: not owned by root", path);
358    if (st->st_mode & 020)
359	tcpd_warn("%s: group writable", path);
360#endif
361    if (st->st_mode & 002)
362	tcpd_warn("%s: world writable", path);
363    if (path[0] == '/' && path[1] != 0) {
364	strrchr(strcpy(buf, path), '/')[0] = 0;
365	(void) check_path(buf[0] ? buf : "/", &stbuf);
366    }
367    return (0);
368}
369