summaryrefslogtreecommitdiff
path: root/scaffold.c
blob: afce15a64e4d1a44c55657b6fb2986ad31b0b120 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
 /*
  * Routines for testing only. Not really industrial strength.
  * 
  * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
  */

#ifndef lint
static char sccs_id[] = "@(#) scaffold.c 1.6 97/03/21 19:27:24";
#endif

/* System libraries. */

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <stdio.h>
#include <syslog.h>
#include <setjmp.h>
#include <string.h>

#ifndef INADDR_NONE
#define	INADDR_NONE	(-1)		/* XXX should be 0xffffffff */
#endif

extern char *malloc();

/* Application-specific. */

#include "tcpd.h"
#include "scaffold.h"

 /*
  * These are referenced by the options module and by rfc931.c.
  */
int     allow_severity = SEVERITY;
int     deny_severity = LOG_WARNING;
int     rfc931_timeout = RFC931_TIMEOUT;

/* dup_hostent - create hostent in one memory block */

static struct hostent *dup_hostent(hp)
struct hostent *hp;
{
    struct hostent_block {
	struct hostent host;
	char   *addr_list[1];
    };
    struct hostent_block *hb;
    int     count;
    char   *data;
    char   *addr;

    for (count = 0; hp->h_addr_list[count] != 0; count++)
	 /* void */ ;

    if ((hb = (struct hostent_block *) malloc(sizeof(struct hostent_block)
			 + (hp->h_length + sizeof(char *)) * count)) == 0) {
	fprintf(stderr, "Sorry, out of memory\n");
	exit(1);
    }
    memset((char *) &hb->host, 0, sizeof(hb->host));
    hb->host.h_length = hp->h_length;
    hb->host.h_addr_list = hb->addr_list;
    hb->host.h_addr_list[count] = 0;
    data = (char *) (hb->host.h_addr_list + count + 1);

    for (count = 0; (addr = hp->h_addr_list[count]) != 0; count++) {
	hb->host.h_addr_list[count] = data + hp->h_length * count;
	memcpy(hb->host.h_addr_list[count], addr, hp->h_length);
    }
    return (&hb->host);
}

/* find_inet_addr - find all addresses for this host, result to free() */

struct hostent *find_inet_addr(host)
char   *host;
{
    struct in_addr addr;
    struct hostent *hp;
    static struct hostent h;
    static char *addr_list[2];

    /*
     * Host address: translate it to internal form.
     */
    if ((addr.s_addr = dot_quad_addr(host)) != INADDR_NONE) {
	h.h_addr_list = addr_list;
	h.h_addr_list[0] = (char *) &addr;
	h.h_length = sizeof(addr);
	return (dup_hostent(&h));
    }

    /*
     * Map host name to a series of addresses. Watch out for non-internet
     * forms or aliases. The NOT_INADDR() is here in case gethostbyname() has
     * been "enhanced" to accept numeric addresses. Make a copy of the
     * address list so that later gethostbyXXX() calls will not clobber it.
     */
    if (NOT_INADDR(host) == 0) {
	tcpd_warn("%s: not an internet address", host);
	return (0);
    }
    if ((hp = gethostbyname(host)) == 0) {
	tcpd_warn("%s: host not found", host);
	return (0);
    }
    if (hp->h_addrtype != AF_INET) {
	tcpd_warn("%d: not an internet host", hp->h_addrtype);
	return (0);
    }
    if (STR_NE(host, hp->h_name)) {
	tcpd_warn("%s: hostname alias", host);
	tcpd_warn("(official name: %.*s)", STRING_LENGTH, hp->h_name);
    }
    return (dup_hostent(hp));
}

/* check_dns - give each address thorough workout, return address count */

int     check_dns(host)
char   *host;
{
    struct request_info request;
    struct sockaddr_in sin;
    struct hostent *hp;
    int     count;
    char   *addr;

    if ((hp = find_inet_addr(host)) == 0)
	return (0);
    request_init(&request, RQ_CLIENT_SIN, &sin, 0);
    sock_methods(&request);
    memset((char *) &sin, 0, sizeof(sin));
    sin.sin_family = AF_INET;

    for (count = 0; (addr = hp->h_addr_list[count]) != 0; count++) {
	memcpy((char *) &sin.sin_addr, addr, sizeof(sin.sin_addr));

	/*
	 * Force host name and address conversions. Use the request structure
	 * as a cache. Detect hostname lookup problems. Any name/name or
	 * name/address conflicts will be reported while eval_hostname() does
	 * its job.
	 */
	request_set(&request, RQ_CLIENT_ADDR, "", RQ_CLIENT_NAME, "", 0);
	if (STR_EQ(eval_hostname(request.client), unknown))
	    tcpd_warn("host address %s->name lookup failed",
		      eval_hostaddr(request.client));
    }
    free((char *) hp);
    return (count);
}

/* dummy function to intercept the real shell_cmd() */

/* ARGSUSED */

void    shell_cmd(command)
char   *command;
{
    if (hosts_access_verbose)
	printf("command: %s", command);
}

/* dummy function  to intercept the real clean_exit() */

/* ARGSUSED */

void    clean_exit(request)
struct request_info *request;
{
    exit(0);
}

/* dummy function  to intercept the real rfc931() */

/* ARGSUSED */

void    rfc931(request)
struct request_info *request;
{
    strcpy(request->user, unknown);
}

/* check_path - examine accessibility */

int     check_path(path, st)
char   *path;
struct stat *st;
{
    struct stat stbuf;
    char    buf[BUFSIZ];

    if (stat(path, st) < 0)
	return (-1);
#ifdef notdef
    if (st->st_uid != 0)
	tcpd_warn("%s: not owned by root", path);
    if (st->st_mode & 020)
	tcpd_warn("%s: group writable", path);
#endif
    if (st->st_mode & 002)
	tcpd_warn("%s: world writable", path);
    if (path[0] == '/' && path[1] != 0) {
	strrchr(strcpy(buf, path), '/')[0] = 0;
	(void) check_path(buf[0] ? buf : "/", &stbuf);
    }
    return (0);
}