1 /*
2  * Routines for testing only. Not really industrial strength.
3  *
4  * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
5  *
6  * $FreeBSD: stable/10/contrib/tcp_wrappers/scaffold.c 323744 2017-09-19 08:34:13Z avg $
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
26#ifndef INADDR_NONE
27#define	INADDR_NONE	(-1)		/* XXX should be 0xffffffff */
28#endif
29
30/* Application-specific. */
31
32#include "tcpd.h"
33#include "scaffold.h"
34
35 /*
36  * These are referenced by the options module and by rfc931.c.
37  */
38int     allow_severity = SEVERITY;
39int     deny_severity = LOG_WARNING;
40int     rfc931_timeout = RFC931_TIMEOUT;
41
42#ifndef INET6
43/* dup_hostent - create hostent in one memory block */
44
45static struct hostent *dup_hostent(hp)
46struct hostent *hp;
47{
48    struct hostent_block {
49	struct hostent host;
50	char   *addr_list[1];
51    };
52    struct hostent_block *hb;
53    int     count;
54    char   *data;
55    char   *addr;
56
57    for (count = 0; hp->h_addr_list[count] != 0; count++)
58	 /* void */ ;
59
60    if ((hb = (struct hostent_block *) malloc(sizeof(struct hostent_block)
61			 + (hp->h_length + sizeof(char *)) * count)) == 0) {
62	fprintf(stderr, "Sorry, out of memory\n");
63	exit(1);
64    }
65    memset((char *) &hb->host, 0, sizeof(hb->host));
66    hb->host.h_length = hp->h_length;
67    hb->host.h_addr_list = hb->addr_list;
68    hb->host.h_addr_list[count] = 0;
69    data = (char *) (hb->host.h_addr_list + count + 1);
70
71    for (count = 0; (addr = hp->h_addr_list[count]) != 0; count++) {
72	hb->host.h_addr_list[count] = data + hp->h_length * count;
73	memcpy(hb->host.h_addr_list[count], addr, hp->h_length);
74    }
75    return (&hb->host);
76}
77#endif
78
79/* find_inet_addr - find all addresses for this host, result to free() */
80
81#ifdef INET6
82struct addrinfo *find_inet_addr(host)
83char   *host;
84{
85    struct addrinfo hints, *res;
86
87    memset(&hints, 0, sizeof(hints));
88    hints.ai_family = PF_UNSPEC;
89    hints.ai_socktype = SOCK_STREAM;
90    hints.ai_flags = AI_PASSIVE | AI_NUMERICHOST;
91    if (getaddrinfo(host, NULL, &hints, &res) == 0)
92	return (res);
93
94    memset(&hints, 0, sizeof(hints));
95    hints.ai_family = PF_UNSPEC;
96    hints.ai_socktype = SOCK_STREAM;
97    hints.ai_flags = AI_PASSIVE | AI_CANONNAME;
98    if (getaddrinfo(host, NULL, &hints, &res) != 0) {
99	tcpd_warn("%s: host not found", host);
100	return (0);
101    }
102    if (res->ai_family != AF_INET6 && res->ai_family != AF_INET) {
103	tcpd_warn("%d: not an internet host", res->ai_family);
104	freeaddrinfo(res);
105	return (0);
106    }
107    if (!res->ai_canonname) {
108	tcpd_warn("%s: hostname alias", host);
109	tcpd_warn("(cannot obtain official name)", res->ai_canonname);
110    } else if (STR_NE(host, res->ai_canonname)) {
111	tcpd_warn("%s: hostname alias", host);
112	tcpd_warn("(official name: %.*s)", STRING_LENGTH, res->ai_canonname);
113    }
114    return (res);
115}
116#else
117struct hostent *find_inet_addr(host)
118char   *host;
119{
120    struct in_addr addr;
121    struct hostent *hp;
122    static struct hostent h;
123    static char *addr_list[2];
124
125    /*
126     * Host address: translate it to internal form.
127     */
128    if ((addr.s_addr = dot_quad_addr(host)) != INADDR_NONE) {
129	h.h_addr_list = addr_list;
130	h.h_addr_list[0] = (char *) &addr;
131	h.h_length = sizeof(addr);
132	return (dup_hostent(&h));
133    }
134
135    /*
136     * Map host name to a series of addresses. Watch out for non-internet
137     * forms or aliases. The NOT_INADDR() is here in case gethostbyname() has
138     * been "enhanced" to accept numeric addresses. Make a copy of the
139     * address list so that later gethostbyXXX() calls will not clobber it.
140     */
141    if (NOT_INADDR(host) == 0) {
142	tcpd_warn("%s: not an internet address", host);
143	return (0);
144    }
145    if ((hp = gethostbyname(host)) == 0) {
146	tcpd_warn("%s: host not found", host);
147	return (0);
148    }
149    if (hp->h_addrtype != AF_INET) {
150	tcpd_warn("%d: not an internet host", hp->h_addrtype);
151	return (0);
152    }
153    if (STR_NE(host, hp->h_name)) {
154	tcpd_warn("%s: hostname alias", host);
155	tcpd_warn("(official name: %.*s)", STRING_LENGTH, hp->h_name);
156    }
157    return (dup_hostent(hp));
158}
159#endif
160
161/* check_dns - give each address thorough workout, return address count */
162
163int     check_dns(host)
164char   *host;
165{
166    struct request_info request;
167#ifdef INET6
168    struct sockaddr_storage sin;
169    struct addrinfo *hp, *res;
170#else
171    struct sockaddr_in sin;
172    struct hostent *hp;
173#endif
174    int     count;
175    char   *addr;
176
177    if ((hp = find_inet_addr(host)) == 0)
178	return (0);
179    request_init(&request, RQ_CLIENT_SIN, &sin, 0);
180    sock_methods(&request);
181#ifndef INET6
182    memset((char *) &sin, 0, sizeof(sin));
183    sin.sin_family = AF_INET;
184#endif
185
186#ifdef INET6
187    for (res = hp, count = 0; res; res = res->ai_next, count++) {
188	memcpy(&sin, res->ai_addr, res->ai_addrlen);
189#else
190    for (count = 0; (addr = hp->h_addr_list[count]) != 0; count++) {
191	memcpy((char *) &sin.sin_addr, addr, sizeof(sin.sin_addr));
192#endif
193
194	/*
195	 * Force host name and address conversions. Use the request structure
196	 * as a cache. Detect hostname lookup problems. Any name/name or
197	 * name/address conflicts will be reported while eval_hostname() does
198	 * its job.
199	 */
200	request_set(&request, RQ_CLIENT_ADDR, "", RQ_CLIENT_NAME, "", 0);
201	if (STR_EQ(eval_hostname(request.client), unknown))
202	    tcpd_warn("host address %s->name lookup failed",
203		      eval_hostaddr(request.client));
204    }
205#ifdef INET6
206    freeaddrinfo(hp);
207#else
208    free((char *) hp);
209#endif
210    return (count);
211}
212
213/* dummy function to intercept the real shell_cmd() */
214
215/* ARGSUSED */
216
217void    shell_cmd(command)
218char   *command;
219{
220    if (hosts_access_verbose)
221	printf("command: %s", command);
222}
223
224/* dummy function  to intercept the real clean_exit() */
225
226/* ARGSUSED */
227
228void    clean_exit(request)
229struct request_info *request;
230{
231    exit(0);
232}
233
234/* check_path - examine accessibility */
235
236int     check_path(path, st)
237char   *path;
238struct stat *st;
239{
240    struct stat stbuf;
241    char    buf[BUFSIZ];
242
243    if (stat(path, st) < 0)
244	return (-1);
245#ifdef notdef
246    if (st->st_uid != 0)
247	tcpd_warn("%s: not owned by root", path);
248    if (st->st_mode & 020)
249	tcpd_warn("%s: group writable", path);
250#endif
251    if (st->st_mode & 002)
252	tcpd_warn("%s: world writable", path);
253    if (path[0] == '/' && path[1] != 0) {
254	strrchr(strcpy(buf, path), '/')[0] = 0;
255	(void) check_path(buf[0] ? buf : "/", &stbuf);
256    }
257    return (0);
258}
259