scaffold.c revision 44744 
1 /*
2  * Routines for testing only. Not really industrial strength.
3  *
4  * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
5  */
6
7#ifndef lint
8static char sccs_id[] = "@(#) scaffold.c 1.6 97/03/21 19:27:24";
9#endif
10
11/* System libraries. */
12
13#include <sys/types.h>
14#include <sys/stat.h>
15#include <sys/socket.h>
16#include <netinet/in.h>
17#include <arpa/inet.h>
18#include <netdb.h>
19#include <stdio.h>
20#include <syslog.h>
21#include <setjmp.h>
22#include <string.h>
23
24#ifndef INADDR_NONE
25#define	INADDR_NONE	(-1)		/* XXX should be 0xffffffff */
26#endif
27
28extern char *malloc();
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/* dup_hostent - create hostent in one memory block */
43
44static struct hostent *dup_hostent(hp)
45struct hostent *hp;
46{
47    struct hostent_block {
48	struct hostent host;
49	char   *addr_list[1];
50    };
51    struct hostent_block *hb;
52    int     count;
53    char   *data;
54    char   *addr;
55
56    for (count = 0; hp->h_addr_list[count] != 0; count++)
57	 /* void */ ;
58
59    if ((hb = (struct hostent_block *) malloc(sizeof(struct hostent_block)
60			 + (hp->h_length + sizeof(char *)) * count)) == 0) {
61	fprintf(stderr, "Sorry, out of memory\n");
62	exit(1);
63    }
64    memset((char *) &hb->host, 0, sizeof(hb->host));
65    hb->host.h_length = hp->h_length;
66    hb->host.h_addr_list = hb->addr_list;
67    hb->host.h_addr_list[count] = 0;
68    data = (char *) (hb->host.h_addr_list + count + 1);
69
70    for (count = 0; (addr = hp->h_addr_list[count]) != 0; count++) {
71	hb->host.h_addr_list[count] = data + hp->h_length * count;
72	memcpy(hb->host.h_addr_list[count], addr, hp->h_length);
73    }
74    return (&hb->host);
75}
76
77/* find_inet_addr - find all addresses for this host, result to free() */
78
79struct hostent *find_inet_addr(host)
80char   *host;
81{
82    struct in_addr addr;
83    struct hostent *hp;
84    static struct hostent h;
85    static char *addr_list[2];
86
87    /*
88     * Host address: translate it to internal form.
89     */
90    if ((addr.s_addr = dot_quad_addr(host)) != INADDR_NONE) {
91	h.h_addr_list = addr_list;
92	h.h_addr_list[0] = (char *) &addr;
93	h.h_length = sizeof(addr);
94	return (dup_hostent(&h));
95    }
96
97    /*
98     * Map host name to a series of addresses. Watch out for non-internet
99     * forms or aliases. The NOT_INADDR() is here in case gethostbyname() has
100     * been "enhanced" to accept numeric addresses. Make a copy of the
101     * address list so that later gethostbyXXX() calls will not clobber it.
102     */
103    if (NOT_INADDR(host) == 0) {
104	tcpd_warn("%s: not an internet address", host);
105	return (0);
106    }
107    if ((hp = gethostbyname(host)) == 0) {
108	tcpd_warn("%s: host not found", host);
109	return (0);
110    }
111    if (hp->h_addrtype != AF_INET) {
112	tcpd_warn("%d: not an internet host", hp->h_addrtype);
113	return (0);
114    }
115    if (STR_NE(host, hp->h_name)) {
116	tcpd_warn("%s: hostname alias", host);
117	tcpd_warn("(official name: %.*s)", STRING_LENGTH, hp->h_name);
118    }
119    return (dup_hostent(hp));
120}
121
122/* check_dns - give each address thorough workout, return address count */
123
124int     check_dns(host)
125char   *host;
126{
127    struct request_info request;
128    struct sockaddr_in sin;
129    struct hostent *hp;
130    int     count;
131    char   *addr;
132
133    if ((hp = find_inet_addr(host)) == 0)
134	return (0);
135    request_init(&request, RQ_CLIENT_SIN, &sin, 0);
136    sock_methods(&request);
137    memset((char *) &sin, 0, sizeof(sin));
138    sin.sin_family = AF_INET;
139
140    for (count = 0; (addr = hp->h_addr_list[count]) != 0; count++) {
141	memcpy((char *) &sin.sin_addr, addr, sizeof(sin.sin_addr));
142
143	/*
144	 * Force host name and address conversions. Use the request structure
145	 * as a cache. Detect hostname lookup problems. Any name/name or
146	 * name/address conflicts will be reported while eval_hostname() does
147	 * its job.
148	 */
149	request_set(&request, RQ_CLIENT_ADDR, "", RQ_CLIENT_NAME, "", 0);
150	if (STR_EQ(eval_hostname(request.client), unknown))
151	    tcpd_warn("host address %s->name lookup failed",
152		      eval_hostaddr(request.client));
153    }
154    free((char *) hp);
155    return (count);
156}
157
158/* dummy function to intercept the real shell_cmd() */
159
160/* ARGSUSED */
161
162void    shell_cmd(command)
163char   *command;
164{
165    if (hosts_access_verbose)
166	printf("command: %s", command);
167}
168
169/* dummy function  to intercept the real clean_exit() */
170
171/* ARGSUSED */
172
173void    clean_exit(request)
174struct request_info *request;
175{
176    exit(0);
177}
178
179/* dummy function  to intercept the real rfc931() */
180
181/* ARGSUSED */
182
183void    rfc931(request)
184struct request_info *request;
185{
186    strcpy(request->user, unknown);
187}
188
189/* check_path - examine accessibility */
190
191int     check_path(path, st)
192char   *path;
193struct stat *st;
194{
195    struct stat stbuf;
196    char    buf[BUFSIZ];
197
198    if (stat(path, st) < 0)
199	return (-1);
200#ifdef notdef
201    if (st->st_uid != 0)
202	tcpd_warn("%s: not owned by root", path);
203    if (st->st_mode & 020)
204	tcpd_warn("%s: group writable", path);
205#endif
206    if (st->st_mode & 002)
207	tcpd_warn("%s: world writable", path);
208    if (path[0] == '/' && path[1] != 0) {
209	strrchr(strcpy(buf, path), '/')[0] = 0;
210	(void) check_path(buf[0] ? buf : "/", &stbuf);
211    }
212    return (0);
213}
214