xref: /freebsd/crypto/heimdal/appl/kf/kfd.c (revision 193d9e768ba63fcfb187cfd17f461f7d41345048)
1 /*
2  * Copyright (c) 1997 - 2002 Kungliga Tekniska Högskolan
3  * (Royal Institute of Technology, Stockholm, Sweden).
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  *
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  *
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * 3. Neither the name of the Institute nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #include "kf_locl.h"
35 RCSID("$Id$");
36 
37 krb5_context context;
38 char krb5_tkfile[MAXPATHLEN];
39 
40 static int help_flag;
41 static int version_flag;
42 static char *port_str;
43 char *service = KF_SERVICE;
44 int do_inetd = 0;
45 static char *regpag_str=NULL;
46 
47 static struct getargs args[] = {
48     { "port", 'p', arg_string, &port_str, "port to listen to", "port" },
49     { "inetd",'i',arg_flag, &do_inetd,
50        "Not started from inetd", NULL },
51     { "regpag",'R',arg_string,&regpag_str,"path to regpag binary","regpag"},
52     { "help", 'h', arg_flag, &help_flag },
53     { "version", 0, arg_flag, &version_flag }
54 };
55 
56 static int num_args = sizeof(args) / sizeof(args[0]);
57 
58 static void
59 usage(int code, struct getargs *args, int num_args)
60 {
61     arg_printusage(args, num_args, NULL, "");
62     exit(code);
63 }
64 
65 static int
66 server_setup(krb5_context *context, int argc, char **argv)
67 {
68     int port = 0;
69     int local_argc;
70 
71     local_argc = krb5_program_setup(context, argc, argv, args, num_args, usage);
72 
73     if(help_flag)
74 	(*usage)(0, args, num_args);
75     if(version_flag) {
76 	print_version(NULL);
77 	exit(0);
78     }
79 
80     if(port_str){
81 	struct servent *s = roken_getservbyname(port_str, "tcp");
82 	if(s)
83 	    port = s->s_port;
84 	else {
85 	    char *ptr;
86 
87 	    port = strtol (port_str, &ptr, 10);
88 	    if (port == 0 && ptr == port_str)
89 		errx (1, "Bad port `%s'", port_str);
90 	    port = htons(port);
91 	}
92     }
93 
94     if (port == 0)
95 	port = krb5_getportbyname (*context, KF_PORT_NAME, "tcp", KF_PORT_NUM);
96 
97     if(argv[local_argc] != NULL)
98         usage(1, args, num_args);
99 
100     return port;
101 }
102 
103 static int protocol_version;
104 
105 static krb5_boolean
106 kfd_match_version(const void *arg, const char *version)
107 {
108     if(strcmp(version, KF_VERSION_1) == 0) {
109 	protocol_version = 1;
110 	return TRUE;
111     } else if (strlen(version) == 4 &&
112 	       version[0] == '0' &&
113 	       version[1] == '.' &&
114 	       (version[2] == '4' || version[2] == '3') &&
115 	       islower((unsigned char)version[3])) {
116 	protocol_version = 0;
117 	return TRUE;
118     }
119     return FALSE;
120 }
121 
122 static int
123 proto (int sock, const char *service)
124 {
125     krb5_auth_context auth_context;
126     krb5_error_code status;
127     krb5_principal server;
128     krb5_ticket *ticket;
129     char *name;
130     char ret_string[10];
131     char hostname[MAXHOSTNAMELEN];
132     krb5_data data;
133     krb5_data remotename;
134     krb5_data tk_file;
135     krb5_ccache ccache;
136     char ccname[MAXPATHLEN];
137     struct passwd *pwd;
138 
139     status = krb5_auth_con_init (context, &auth_context);
140     if (status)
141 	krb5_err(context, 1, status, "krb5_auth_con_init");
142 
143     status = krb5_auth_con_setaddrs_from_fd (context,
144 					     auth_context,
145 					     &sock);
146     if (status)
147 	krb5_err(context, 1, status, "krb5_auth_con_setaddr");
148 
149     if(gethostname (hostname, sizeof(hostname)) < 0)
150 	krb5_err(context, 1, errno, "gethostname");
151 
152     status = krb5_sname_to_principal (context,
153 				      hostname,
154 				      service,
155 				      KRB5_NT_SRV_HST,
156 				      &server);
157     if (status)
158 	krb5_err(context, 1, status, "krb5_sname_to_principal");
159 
160     status = krb5_recvauth_match_version (context,
161 					  &auth_context,
162 					  &sock,
163 					  kfd_match_version,
164 					  NULL,
165 					  server,
166 					  0,
167 					  NULL,
168 					  &ticket);
169     if (status)
170 	krb5_err(context, 1, status, "krb5_recvauth");
171 
172     status = krb5_unparse_name (context,
173 				ticket->client,
174 				&name);
175     if (status)
176 	krb5_err(context, 1, status, "krb5_unparse_name");
177 
178     if(protocol_version == 0) {
179 	data.data = "old clnt"; /* XXX old clients only had room for
180                                    10 bytes of message, and also
181                                    didn't show it to the user */
182 	data.length = strlen(data.data) + 1;
183 	krb5_write_message(context, &sock, &data);
184 	sleep(2); /* XXX give client time to finish */
185 	krb5_errx(context, 1, "old client; exiting");
186     }
187 
188     status=krb5_read_priv_message (context, auth_context,
189 				   &sock, &remotename);
190     if (status)
191 	krb5_err(context, 1, status, "krb5_read_message");
192     status=krb5_read_priv_message (context, auth_context,
193 				   &sock, &tk_file);
194     if (status)
195 	krb5_err(context, 1, status, "krb5_read_message");
196 
197     krb5_data_zero (&data);
198 
199     if(((char*)remotename.data)[remotename.length-1] != '\0')
200 	krb5_errx(context, 1, "unterminated received");
201     if(((char*)tk_file.data)[tk_file.length-1] != '\0')
202 	krb5_errx(context, 1, "unterminated received");
203 
204     status = krb5_read_priv_message(context, auth_context, &sock, &data);
205 
206     if (status) {
207 	krb5_err(context, 1, errno, "krb5_read_priv_message");
208 	goto out;
209     }
210 
211     pwd = getpwnam ((char *)(remotename.data));
212     if (pwd == NULL) {
213 	status=1;
214 	krb5_warnx(context, "getpwnam: %s failed",(char *)(remotename.data));
215 	goto out;
216     }
217 
218     if(!krb5_kuserok (context,
219 		      ticket->client,
220 		      (char *)(remotename.data))) {
221 	status=1;
222 	krb5_warnx(context, "krb5_kuserok: permission denied");
223 	goto out;
224     }
225 
226     if (setgid(pwd->pw_gid) < 0) {
227 	krb5_warn(context, errno, "setgid");
228 	goto out;
229     }
230     if (setuid(pwd->pw_uid) < 0) {
231 	krb5_warn(context, errno, "setuid");
232 	goto out;
233     }
234 
235     if (tk_file.length != 1)
236 	snprintf (ccname, sizeof(ccname), "%s", (char *)(tk_file.data));
237     else
238 	snprintf (ccname, sizeof(ccname), "FILE:/tmp/krb5cc_%lu",
239 		  (unsigned long)pwd->pw_uid);
240 
241     status = krb5_cc_resolve (context, ccname, &ccache);
242     if (status) {
243 	krb5_warn(context, status, "krb5_cc_resolve");
244         goto out;
245     }
246     status = krb5_cc_initialize (context, ccache, ticket->client);
247     if (status) {
248 	krb5_warn(context, status, "krb5_cc_initialize");
249         goto out;
250     }
251     status = krb5_rd_cred2 (context, auth_context, ccache, &data);
252     krb5_cc_close (context, ccache);
253     if (status) {
254 	krb5_warn(context, status, "krb5_rd_cred");
255         goto out;
256 
257     }
258     strlcpy(krb5_tkfile,ccname,sizeof(krb5_tkfile));
259     krb5_warnx(context, "%s forwarded ticket to %s,%s",
260 	       name,
261 	       (char *)(remotename.data),ccname);
262   out:
263     if (status) {
264 	strlcpy(ret_string, "no", sizeof(ret_string));
265 	krb5_warnx(context, "failed");
266     } else  {
267 	strlcpy(ret_string, "ok", sizeof(ret_string));
268     }
269 
270     krb5_data_free (&tk_file);
271     krb5_data_free (&remotename);
272     krb5_data_free (&data);
273     free(name);
274 
275     data.data = ret_string;
276     data.length = strlen(ret_string) + 1;
277     status = krb5_write_priv_message(context, auth_context, &sock, &data);
278     krb5_auth_con_free(context, auth_context);
279 
280     return status;
281 }
282 
283 static int
284 doit (int port, const char *service)
285 {
286     if (do_inetd)
287 	mini_inetd(port, NULL);
288     return proto (STDIN_FILENO, service);
289 }
290 
291 int
292 main(int argc, char **argv)
293 {
294     int port;
295     int ret;
296     krb5_log_facility *fac;
297 
298     setprogname (argv[0]);
299     roken_openlog (argv[0], LOG_ODELAY | LOG_PID,LOG_AUTH);
300     port = server_setup(&context, argc, argv);
301     ret = krb5_openlog(context, "kfd", &fac);
302     if(ret) krb5_err(context, 1, ret, "krb5_openlog");
303     ret = krb5_set_warn_dest(context, fac);
304     if(ret) krb5_err(context, 1, ret, "krb5_set_warn_dest");
305 
306     ret = doit (port, service);
307     closelog();
308     if (ret == 0 && regpag_str != NULL)
309         ret = execl(regpag_str, "regpag", "-t", krb5_tkfile, "-r", NULL);
310     return ret;
311 }
312