 67422a6b02
			
		
	
	67422a6b02
	
	
	
		
			
			git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@9704 ec53bebd-3082-4978-b11e-865c3cabbd6b
		
			
				
	
	
		
			946 lines
		
	
	
		
			22 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			946 lines
		
	
	
		
			22 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Copyright (c) 1997-2001 Kungliga Tekniska Högskolan
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|  * (Royal Institute of Technology, Stockholm, Sweden). 
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|  * All rights reserved. 
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|  *
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|  * Redistribution and use in source and binary forms, with or without 
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|  * modification, are permitted provided that the following conditions 
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|  * are met: 
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|  *
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|  * 1. Redistributions of source code must retain the above copyright 
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|  *    notice, this list of conditions and the following disclaimer. 
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|  *
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|  * 2. Redistributions in binary form must reproduce the above copyright 
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|  *    notice, this list of conditions and the following disclaimer in the 
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|  *    documentation and/or other materials provided with the distribution. 
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|  *
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|  * 3. Neither the name of the Institute nor the names of its contributors 
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|  *    may be used to endorse or promote products derived from this software 
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|  *    without specific prior written permission. 
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|  *
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|  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND 
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|  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
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|  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
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|  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE 
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|  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 
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|  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 
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|  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 
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|  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 
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|  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 
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|  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 
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|  * SUCH DAMAGE. 
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|  */
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| 
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| #include "rsh_locl.h"
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| RCSID("$Id$");
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| 
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| int
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| login_access( struct passwd *user, char *from);
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| 
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| enum auth_method auth_method;
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| 
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| krb5_context context;
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| krb5_keyblock *keyblock;
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| krb5_crypto crypto;
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| 
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| #ifdef KRB4
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| des_key_schedule schedule;
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| des_cblock iv;
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| #endif
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| 
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| krb5_ccache ccache, ccache2;
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| int kerberos_status = 0;
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| 
 | |
| int do_encrypt = 0;
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| 
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| static int do_unique_tkfile           = 0;
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| static char tkfile[MAXPATHLEN] = "";
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| 
 | |
| static int do_inetd = 1;
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| static char *port_str;
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| static int do_rhosts;
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| static int do_kerberos = 0;
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| static int do_vacuous = 0;
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| static int do_log = 1;
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| static int do_newpag = 1;
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| static int do_version;
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| static int do_help = 0;
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| 
 | |
| #if defined(DCE)
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| int dfsk5ok = 0;
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| int dfspag = 0;
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| int dfsfwd = 0;
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| krb5_ticket *user_ticket;
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| #endif
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| 
 | |
| static void
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| syslog_and_die (const char *m, ...)
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|     __attribute__ ((format (printf, 1, 2)));
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| 
 | |
| static void
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| syslog_and_die (const char *m, ...)
 | |
| {
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|     va_list args;
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| 
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|     va_start(args, m);
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|     vsyslog (LOG_ERR, m, args);
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|     va_end(args);
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|     exit (1);
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| }
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| 
 | |
| static void
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| fatal (int sock, const char *m, ...)
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|     __attribute__ ((format (printf, 2, 3)));
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| 
 | |
| static void
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| fatal (int sock, const char *m, ...)
 | |
| {
 | |
|     va_list args;
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|     char buf[BUFSIZ];
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|     size_t len;
 | |
| 
 | |
|     *buf = 1;
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|     va_start(args, m);
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|     len = vsnprintf (buf + 1, sizeof(buf) - 1, m, args);
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|     va_end(args);
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|     syslog (LOG_ERR, "%s", buf + 1);
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|     net_write (sock, buf, len + 1);
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|     exit (1);
 | |
| }
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| 
 | |
| static void
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| read_str (int s, char *str, size_t sz, char *expl)
 | |
| {
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|     while (sz > 0) {
 | |
| 	if (net_read (s, str, 1) != 1)
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| 	    syslog_and_die ("read: %m");
 | |
| 	if (*str == '\0')
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| 	    return;
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| 	--sz;
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| 	++str;
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|     }
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|     fatal (s, "%s too long", expl);
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| }
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| 
 | |
| static int
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| recv_bsd_auth (int s, u_char *buf,
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| 	       struct sockaddr_in *thisaddr,
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| 	       struct sockaddr_in *thataddr,
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| 	       char *client_username,
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| 	       char *server_username,
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| 	       char *cmd)
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| {
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|     struct passwd *pwd;
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| 
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|     read_str (s, client_username, USERNAME_SZ, "local username");
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|     read_str (s, server_username, USERNAME_SZ, "remote username");
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|     read_str (s, cmd, COMMAND_SZ, "command");
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|     pwd = getpwnam(server_username);
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|     if (pwd == NULL)
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| 	fatal(s, "Login incorrect.");
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|     if (iruserok(thataddr->sin_addr.s_addr, pwd->pw_uid == 0,
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| 		 client_username, server_username))
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| 	fatal(s, "Login incorrect.");
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|     return 0;
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| }
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| 
 | |
| #ifdef KRB4
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| static int
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| recv_krb4_auth (int s, u_char *buf,
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| 		struct sockaddr *thisaddr,
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| 		struct sockaddr *thataddr,
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| 		char *client_username,
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| 		char *server_username,
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| 		char *cmd)
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| {
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|     int status;
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|     int32_t options;
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|     KTEXT_ST ticket;
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|     AUTH_DAT auth;
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|     char instance[INST_SZ + 1];
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|     char version[KRB_SENDAUTH_VLEN + 1];
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| 
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|     if (memcmp (buf, KRB_SENDAUTH_VERS, 4) != 0)
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| 	return -1;
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|     if (net_read (s, buf + 4, KRB_SENDAUTH_VLEN - 4) !=
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| 	KRB_SENDAUTH_VLEN - 4)
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| 	syslog_and_die ("reading auth info: %m");
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|     if (memcmp (buf, KRB_SENDAUTH_VERS, KRB_SENDAUTH_VLEN) != 0)
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| 	syslog_and_die("unrecognized auth protocol: %.8s", buf);
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| 
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|     options = KOPT_IGNORE_PROTOCOL;
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|     if (do_encrypt)
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| 	options |= KOPT_DO_MUTUAL;
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|     k_getsockinst (s, instance, sizeof(instance));
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|     status = krb_recvauth (options,
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| 			   s,
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| 			   &ticket,
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| 			   "rcmd",
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| 			   instance,
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| 			   (struct sockaddr_in *)thataddr,
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| 			   (struct sockaddr_in *)thisaddr,
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| 			   &auth,
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| 			   "",
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| 			   schedule,
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| 			   version);
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|     if (status != KSUCCESS)
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| 	syslog_and_die ("recvauth: %s", krb_get_err_text(status));
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|     if (strncmp (version, KCMD_VERSION, KRB_SENDAUTH_VLEN) != 0)
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| 	syslog_and_die ("bad version: %s", version);
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| 
 | |
|     read_str (s, server_username, USERNAME_SZ, "remote username");
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|     if (kuserok (&auth, server_username) != 0)
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| 	fatal (s, "Permission denied");
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|     read_str (s, cmd, COMMAND_SZ, "command");
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| 
 | |
|     syslog(LOG_INFO|LOG_AUTH,
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| 	   "kerberos v4 shell from %s on %s as %s, cmd '%.80s'",
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| 	   krb_unparse_name_long(auth.pname, auth.pinst, auth.prealm),
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| 
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| 	   inet_ntoa(((struct sockaddr_in *)thataddr)->sin_addr),
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| 	   server_username,
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| 	   cmd);
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| 
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|     memcpy (iv, auth.session, sizeof(iv));
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| 
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|     return 0;
 | |
| }
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| 
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| #endif /* KRB4 */
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| 
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| static int 
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| save_krb5_creds (int s,
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|                  krb5_auth_context auth_context,
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|                  krb5_principal client)
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| 
 | |
| {
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|     int ret;
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|     krb5_data remote_cred;
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|  
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|     krb5_data_zero (&remote_cred);
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|     ret= krb5_read_message (context, (void *)&s, &remote_cred);
 | |
|     if (ret) {
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| 	krb5_data_free(&remote_cred);
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| 	return 0;
 | |
|     }
 | |
|     if (remote_cred.length == 0)
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| 	return 0;
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|  
 | |
|     ret = krb5_cc_gen_new(context, &krb5_mcc_ops, &ccache);
 | |
|     if (ret) {
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| 	krb5_data_free(&remote_cred);
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| 	return 0;
 | |
|     }
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|   
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|     krb5_cc_initialize(context,ccache,client);
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|     ret = krb5_rd_cred2(context, auth_context, ccache, &remote_cred);
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|     krb5_data_free (&remote_cred);
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|     if (ret)
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| 	return 0;
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|     return 1;
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| }
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| 
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| static void
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| krb5_start_session (void)
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| {
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|     krb5_error_code ret;
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| 
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|     ret = krb5_cc_resolve (context, tkfile, &ccache2);
 | |
|     if (ret) {
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| 	krb5_cc_destroy(context, ccache);
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| 	return;
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|     }
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| 
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|     ret = krb5_cc_copy_cache (context, ccache, ccache2);
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|     if (ret) {
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| 	krb5_cc_destroy(context, ccache);
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| 	return ;
 | |
|     }
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| 
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|     krb5_cc_close(context, ccache2);
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|     krb5_cc_destroy(context, ccache);
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|     return;
 | |
| }
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| 
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| static int
 | |
| recv_krb5_auth (int s, u_char *buf,
 | |
| 		struct sockaddr *thisaddr,
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| 		struct sockaddr *thataddr,
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| 		char *client_username,
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| 		char *server_username,
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| 		char *cmd)
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| {
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|     u_int32_t len;
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|     krb5_auth_context auth_context = NULL;
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|     krb5_ticket *ticket;
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|     krb5_error_code status;
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|     krb5_data cksum_data;
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|     krb5_principal server;
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| 
 | |
|     if (memcmp (buf, "\x00\x00\x00\x13", 4) != 0)
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| 	return -1;
 | |
|     len = (buf[0] << 24) | (buf[1] << 16) | (buf[2] << 8) | (buf[3]);
 | |
| 	
 | |
|     if (net_read(s, buf, len) != len)
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| 	syslog_and_die ("reading auth info: %m");
 | |
|     if (len != sizeof(KRB5_SENDAUTH_VERSION)
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| 	|| memcmp (buf, KRB5_SENDAUTH_VERSION, len) != 0)
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| 	syslog_and_die ("bad sendauth version: %.8s", buf);
 | |
|     
 | |
|     status = krb5_sock_to_principal (context,
 | |
| 				     s,
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| 				     "host",
 | |
| 				     KRB5_NT_SRV_HST,
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| 				     &server);
 | |
|     if (status)
 | |
| 	syslog_and_die ("krb5_sock_to_principal: %s",
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| 			krb5_get_err_text(context, status));
 | |
| 
 | |
|     status = krb5_recvauth(context,
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| 			   &auth_context,
 | |
| 			   &s,
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| 			   KCMD_VERSION,
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| 			   server,
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| 			   KRB5_RECVAUTH_IGNORE_VERSION,
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| 			   NULL,
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| 			   &ticket);
 | |
|     krb5_free_principal (context, server);
 | |
|     if (status)
 | |
| 	syslog_and_die ("krb5_recvauth: %s",
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| 			krb5_get_err_text(context, status));
 | |
| 
 | |
|     read_str (s, server_username, USERNAME_SZ, "remote username");
 | |
|     read_str (s, cmd, COMMAND_SZ, "command");
 | |
|     read_str (s, client_username, COMMAND_SZ, "local username");
 | |
| 
 | |
|     status = krb5_auth_con_getkey (context, auth_context, &keyblock);
 | |
|     if (status)
 | |
|        syslog_and_die ("krb5_auth_con_getkey: %s",
 | |
|                        krb5_get_err_text(context, status));
 | |
| 
 | |
|     status = krb5_crypto_init(context, keyblock, 0, &crypto);
 | |
|     if(status)
 | |
| 	syslog_and_die("krb5_crypto_init: %s", 
 | |
| 		       krb5_get_err_text(context, status));
 | |
| 
 | |
|     
 | |
|     cksum_data.length = asprintf ((char **)&cksum_data.data,
 | |
| 				  "%u:%s%s",
 | |
| 				  ntohs(socket_get_port (thisaddr)),
 | |
| 				  cmd,
 | |
| 				  server_username);
 | |
| 
 | |
|     status = krb5_verify_authenticator_checksum(context, 
 | |
| 						auth_context,
 | |
| 						cksum_data.data, 
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| 						cksum_data.length);
 | |
| 
 | |
|     if (status)
 | |
| 	syslog_and_die ("krb5_verify_authenticator_checksum: %s",
 | |
| 			krb5_get_err_text(context, status));
 | |
| 
 | |
|     free (cksum_data.data);
 | |
| 
 | |
|     if (strncmp (client_username, "-u ", 3) == 0) {
 | |
| 	do_unique_tkfile = 1;
 | |
| 	memmove (client_username, client_username + 3,
 | |
| 		 strlen(client_username) - 2);
 | |
|     }
 | |
| 
 | |
|     if (strncmp (client_username, "-U ", 3) == 0) {
 | |
| 	char *end, *temp_tkfile;
 | |
| 
 | |
| 	do_unique_tkfile = 1;
 | |
| 	if (strncmp (server_username + 3, "FILE:", 5) == 0) {
 | |
| 	    temp_tkfile = tkfile;
 | |
| 	} else {
 | |
| 	    strcpy (tkfile, "FILE:");
 | |
| 	    temp_tkfile = tkfile + 5;
 | |
| 	}
 | |
| 	end = strchr(client_username + 3,' ');
 | |
| 	strncpy(temp_tkfile, client_username + 3, end - client_username - 3);
 | |
| 	temp_tkfile[end - client_username - 3] = '\0';
 | |
| 	memmove (client_username, end +1, strlen(end+1)+1);
 | |
|     }
 | |
| 
 | |
|     kerberos_status = save_krb5_creds (s, auth_context, ticket->client);
 | |
| 
 | |
|     if(!krb5_kuserok (context,
 | |
| 		     ticket->client,
 | |
| 		     server_username))
 | |
| 	fatal (s, "Permission denied");
 | |
| 
 | |
|     if (strncmp (cmd, "-x ", 3) == 0) {
 | |
| 	do_encrypt = 1;
 | |
| 	memmove (cmd, cmd + 3, strlen(cmd) - 2);
 | |
|     } else {
 | |
| 	if(do_encrypt)
 | |
| 	    fatal (s, "Encryption required");
 | |
| 	do_encrypt = 0;
 | |
|     }
 | |
| 
 | |
|     {
 | |
| 	char *name;
 | |
| 
 | |
| 	if (krb5_unparse_name (context, ticket->client, &name) == 0) {
 | |
| 	    char addr_str[256];
 | |
| 
 | |
| 	    if (inet_ntop (thataddr->sa_family,
 | |
| 			   socket_get_address (thataddr),
 | |
| 			   addr_str, sizeof(addr_str)) == NULL)
 | |
| 		strlcpy (addr_str, "unknown address",
 | |
| 				 sizeof(addr_str));
 | |
| 
 | |
| 	    syslog(LOG_INFO|LOG_AUTH,
 | |
| 		   "kerberos v5 shell from %s on %s as %s, cmd '%.80s'",
 | |
| 		   name,
 | |
| 		   addr_str,
 | |
| 		   server_username,
 | |
| 		   cmd);
 | |
| 	    free (name);
 | |
| 	}
 | |
|     }	   
 | |
| 
 | |
| #if defined(DCE)
 | |
|     user_ticket = ticket;
 | |
| #endif
 | |
| 
 | |
|     return 0;
 | |
| }
 | |
| 
 | |
| static void
 | |
| loop (int from0, int to0,
 | |
|       int to1,   int from1,
 | |
|       int to2,   int from2)
 | |
| {
 | |
|     fd_set real_readset;
 | |
|     int max_fd;
 | |
|     int count = 2;
 | |
| 
 | |
|     if(from0 >= FD_SETSIZE || from1 >= FD_SETSIZE || from2 >= FD_SETSIZE)
 | |
| 	errx (1, "fd too large");
 | |
| 
 | |
|     FD_ZERO(&real_readset);
 | |
|     FD_SET(from0, &real_readset);
 | |
|     FD_SET(from1, &real_readset);
 | |
|     FD_SET(from2, &real_readset);
 | |
|     max_fd = max(from0, max(from1, from2)) + 1;
 | |
|     for (;;) {
 | |
| 	int ret;
 | |
| 	fd_set readset = real_readset;
 | |
| 	char buf[RSH_BUFSIZ];
 | |
| 
 | |
| 	ret = select (max_fd, &readset, NULL, NULL, NULL);
 | |
| 	if (ret < 0) {
 | |
| 	    if (errno == EINTR)
 | |
| 		continue;
 | |
| 	    else
 | |
| 		syslog_and_die ("select: %m");
 | |
| 	}
 | |
| 	if (FD_ISSET(from0, &readset)) {
 | |
| 	    ret = do_read (from0, buf, sizeof(buf));
 | |
| 	    if (ret < 0)
 | |
| 		syslog_and_die ("read: %m");
 | |
| 	    else if (ret == 0) {
 | |
| 		close (from0);
 | |
| 		close (to0);
 | |
| 		FD_CLR(from0, &real_readset);
 | |
| 	    } else
 | |
| 		net_write (to0, buf, ret);
 | |
| 	}
 | |
| 	if (FD_ISSET(from1, &readset)) {
 | |
| 	    ret = read (from1, buf, sizeof(buf));
 | |
| 	    if (ret < 0)
 | |
| 		syslog_and_die ("read: %m");
 | |
| 	    else if (ret == 0) {
 | |
| 		close (from1);
 | |
| 		close (to1);
 | |
| 		FD_CLR(from1, &real_readset);
 | |
| 		if (--count == 0)
 | |
| 		    exit (0);
 | |
| 	    } else
 | |
| 		do_write (to1, buf, ret);
 | |
| 	}
 | |
| 	if (FD_ISSET(from2, &readset)) {
 | |
| 	    ret = read (from2, buf, sizeof(buf));
 | |
| 	    if (ret < 0)
 | |
| 		syslog_and_die ("read: %m");
 | |
| 	    else if (ret == 0) {
 | |
| 		close (from2);
 | |
| 		close (to2);
 | |
| 		FD_CLR(from2, &real_readset);
 | |
| 		if (--count == 0)
 | |
| 		    exit (0);
 | |
| 	    } else
 | |
| 		do_write (to2, buf, ret);
 | |
| 	}
 | |
|    }
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Used by `setup_copier' to create some pipe-like means of
 | |
|  * communcation.  Real pipes would probably be the best thing, but
 | |
|  * then the shell doesn't understand it's talking to rshd.  If
 | |
|  * socketpair doesn't work everywhere, some autoconf magic would have
 | |
|  * to be added here.
 | |
|  *
 | |
|  * If it fails creating the `pipe', it aborts by calling fatal.
 | |
|  */
 | |
| 
 | |
| static void
 | |
| pipe_a_like (int fd[2])
 | |
| {
 | |
|     if (socketpair (AF_UNIX, SOCK_STREAM, 0, fd) < 0)
 | |
| 	fatal (STDOUT_FILENO, "socketpair: %m");
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Start a child process and leave the parent copying data to and from it.  */
 | |
| 
 | |
| static void
 | |
| setup_copier (void)
 | |
| {
 | |
|     int p0[2], p1[2], p2[2];
 | |
|     pid_t pid;
 | |
| 
 | |
|     pipe_a_like(p0);
 | |
|     pipe_a_like(p1);
 | |
|     pipe_a_like(p2);
 | |
|     pid = fork ();
 | |
|     if (pid < 0)
 | |
| 	fatal (STDOUT_FILENO, "fork: %m");
 | |
|     if (pid == 0) { /* child */
 | |
| 	close (p0[1]);
 | |
| 	close (p1[0]);
 | |
| 	close (p2[0]);
 | |
| 	dup2 (p0[0], STDIN_FILENO);
 | |
| 	dup2 (p1[1], STDOUT_FILENO);
 | |
| 	dup2 (p2[1], STDERR_FILENO);
 | |
| 	close (p0[0]);
 | |
| 	close (p1[1]);
 | |
| 	close (p2[1]);
 | |
|     } else { /* parent */
 | |
| 	close (p0[0]);
 | |
| 	close (p1[1]);
 | |
| 	close (p2[1]);
 | |
| 
 | |
| 	if (net_write (STDOUT_FILENO, "", 1) != 1)
 | |
| 	    fatal (STDOUT_FILENO, "write failed");
 | |
| 
 | |
| 	loop (STDIN_FILENO, p0[1],
 | |
| 	      STDOUT_FILENO, p1[0],
 | |
| 	      STDERR_FILENO, p2[0]);
 | |
|     }
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Is `port' a ``reserverd'' port?
 | |
|  */
 | |
| 
 | |
| static int
 | |
| is_reserved(u_short port)
 | |
| {
 | |
|     return ntohs(port) < IPPORT_RESERVED;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Set the necessary part of the environment in `env'.
 | |
|  */
 | |
| 
 | |
| static void
 | |
| setup_environment (char ***env, const struct passwd *pwd)
 | |
| {
 | |
|     int i, j, path;
 | |
|     char **e;
 | |
| 
 | |
|     i = 0;
 | |
|     path = 0;
 | |
|     *env = NULL;
 | |
| 
 | |
|     i = read_environment(_PATH_ETC_ENVIRONMENT, env);
 | |
|     e = *env;
 | |
|     for (j = 0; j < i; j++) {
 | |
| 	if (!strncmp(e[j], "PATH=", 5)) {
 | |
| 	    path = 1;
 | |
| 	}
 | |
|     }
 | |
| 
 | |
|     e = *env;
 | |
|     e = realloc(e, (i + 7) * sizeof(char *));
 | |
| 
 | |
|     asprintf (&e[i++], "USER=%s",  pwd->pw_name);
 | |
|     asprintf (&e[i++], "HOME=%s",  pwd->pw_dir);
 | |
|     asprintf (&e[i++], "SHELL=%s", pwd->pw_shell);
 | |
|     if (! path) {
 | |
| 	asprintf (&e[i++], "PATH=%s",  _PATH_DEFPATH);
 | |
|     }
 | |
|     asprintf (&e[i++], "SSH_CLIENT=only_to_make_bash_happy");
 | |
| #if defined(DCE)
 | |
|     if (getenv("KRB5CCNAME"))
 | |
| 	asprintf (&e[i++], "KRB5CCNAME=%s",  getenv("KRB5CCNAME"));
 | |
| #else
 | |
|     if (do_unique_tkfile)
 | |
| 	asprintf (&e[i++], "KRB5CCNAME=%s", tkfile);
 | |
| #endif
 | |
|     e[i++] = NULL;
 | |
|     *env = e;
 | |
| }
 | |
| 
 | |
| static void
 | |
| doit (int do_kerberos, int check_rhosts)
 | |
| {
 | |
|     u_char buf[BUFSIZ];
 | |
|     u_char *p;
 | |
|     struct sockaddr_storage thisaddr_ss;
 | |
|     struct sockaddr *thisaddr = (struct sockaddr *)&thisaddr_ss;
 | |
|     struct sockaddr_storage thataddr_ss;
 | |
|     struct sockaddr *thataddr = (struct sockaddr *)&thataddr_ss;
 | |
|     struct sockaddr_storage erraddr_ss;
 | |
|     struct sockaddr *erraddr = (struct sockaddr *)&erraddr_ss;
 | |
|     socklen_t thisaddr_len, thataddr_len;
 | |
|     int port;
 | |
|     int errsock = -1;
 | |
|     char client_user[COMMAND_SZ], server_user[USERNAME_SZ];
 | |
|     char cmd[COMMAND_SZ];
 | |
|     struct passwd *pwd;
 | |
|     int s = STDIN_FILENO;
 | |
|     char **env;
 | |
|     int ret;
 | |
|     char that_host[NI_MAXHOST];
 | |
| 
 | |
|     thisaddr_len = sizeof(thisaddr_ss);
 | |
|     if (getsockname (s, thisaddr, &thisaddr_len) < 0)
 | |
| 	syslog_and_die("getsockname: %m");
 | |
|     thataddr_len = sizeof(thataddr_ss);
 | |
|     if (getpeername (s, thataddr, &thataddr_len) < 0)
 | |
| 	syslog_and_die ("getpeername: %m");
 | |
| 
 | |
|     if (!do_kerberos && !is_reserved(socket_get_port(thataddr)))
 | |
| 	fatal(s, "Permission denied");
 | |
| 
 | |
|     p = buf;
 | |
|     port = 0;
 | |
|     for(;;) {
 | |
| 	if (net_read (s, p, 1) != 1)
 | |
| 	    syslog_and_die ("reading port number: %m");
 | |
| 	if (*p == '\0')
 | |
| 	    break;
 | |
| 	else if (isdigit(*p))
 | |
| 	    port = port * 10 + *p - '0';
 | |
| 	else
 | |
| 	    syslog_and_die ("non-digit in port number: %c", *p);
 | |
|     }
 | |
| 
 | |
|     if (!do_kerberos && !is_reserved(htons(port)))
 | |
| 	fatal(s, "Permission denied");
 | |
| 
 | |
|     if (port) {
 | |
| 	int priv_port = IPPORT_RESERVED - 1;
 | |
| 
 | |
| 	/* 
 | |
| 	 * There's no reason to require a ``privileged'' port number
 | |
| 	 * here, but for some reason the brain dead rsh clients
 | |
| 	 * do... :-(
 | |
| 	 */
 | |
| 
 | |
| 	erraddr->sa_family = thataddr->sa_family;
 | |
| 	socket_set_address_and_port (erraddr,
 | |
| 				     socket_get_address (thataddr),
 | |
| 				     htons(port));
 | |
| 
 | |
| 	/*
 | |
| 	 * we only do reserved port for IPv4
 | |
| 	 */
 | |
| 
 | |
| 	if (erraddr->sa_family == AF_INET)
 | |
| 	    errsock = rresvport (&priv_port);
 | |
| 	else
 | |
| 	    errsock = socket (erraddr->sa_family, SOCK_STREAM, 0);
 | |
| 	if (errsock < 0)
 | |
| 	    syslog_and_die ("socket: %m");
 | |
| 	if (connect (errsock,
 | |
| 		     erraddr,
 | |
| 		     socket_sockaddr_size (erraddr)) < 0) {
 | |
| 	    syslog (LOG_WARNING, "connect: %m");
 | |
| 	    close (errsock);
 | |
| 	}
 | |
|     }
 | |
|     
 | |
|     if(do_kerberos) {
 | |
| 	if (net_read (s, buf, 4) != 4)
 | |
| 	    syslog_and_die ("reading auth info: %m");
 | |
|     
 | |
| #ifdef KRB4
 | |
| 	if (recv_krb4_auth (s, buf, thisaddr, thataddr,
 | |
| 			    client_user,
 | |
| 			    server_user,
 | |
| 			    cmd) == 0)
 | |
| 	    auth_method = AUTH_KRB4;
 | |
| 	else
 | |
| #endif /* KRB4 */
 | |
| 	    if(recv_krb5_auth (s, buf, thisaddr, thataddr,
 | |
| 			       client_user,
 | |
| 			       server_user,
 | |
| 			       cmd) == 0)
 | |
| 		auth_method = AUTH_KRB5;
 | |
| 	    else
 | |
| 		syslog_and_die ("unrecognized auth protocol: %x %x %x %x",
 | |
| 				buf[0], buf[1], buf[2], buf[3]);
 | |
|     } else {
 | |
| 	if(recv_bsd_auth (s, buf,
 | |
| 			  (struct sockaddr_in *)thisaddr,
 | |
| 			  (struct sockaddr_in *)thataddr,
 | |
| 			  client_user,
 | |
| 			  server_user,
 | |
| 			  cmd) == 0) {
 | |
| 	    auth_method = AUTH_BROKEN;
 | |
| 	    if(do_vacuous) {
 | |
| 		printf("Remote host requires Kerberos authentication\n");
 | |
| 		exit(0);
 | |
| 	    }
 | |
| 	} else
 | |
| 	    syslog_and_die("recv_bsd_auth failed");
 | |
|     }
 | |
| 
 | |
| #if defined(DCE) && defined(_AIX)
 | |
|     esetenv("AUTHSTATE", "DCE", 1);
 | |
| #endif
 | |
| 
 | |
|     pwd = getpwnam (server_user);
 | |
|     if (pwd == NULL)
 | |
| 	fatal (s, "Login incorrect.");
 | |
| 
 | |
|     if (*pwd->pw_shell == '\0')
 | |
| 	pwd->pw_shell = _PATH_BSHELL;
 | |
| 
 | |
|     if (pwd->pw_uid != 0 && access (_PATH_NOLOGIN, F_OK) == 0)
 | |
| 	fatal (s, "Login disabled.");
 | |
| 
 | |
| 
 | |
|     ret = getnameinfo_verified (thataddr, thataddr_len,
 | |
| 				that_host, sizeof(that_host),
 | |
| 				NULL, 0, 0);
 | |
|     if (ret)
 | |
| 	fatal (s, "getnameinfo: %s", gai_strerror(ret));
 | |
| 
 | |
|     if (login_access(pwd, that_host) == 0) {
 | |
| 	syslog(LOG_NOTICE, "Kerberos rsh denied to %s from %s",
 | |
| 	       server_user, that_host);
 | |
| 	fatal(s, "Permission denied");
 | |
|     }
 | |
| 
 | |
| #ifdef HAVE_GETSPNAM
 | |
|     {
 | |
| 	struct spwd *sp;
 | |
| 	long    today;
 | |
|     
 | |
| 	sp = getspnam(server_user);
 | |
| 	if (sp != NULL) {
 | |
| 	    today = time(0)/(24L * 60 * 60);
 | |
| 	    if (sp->sp_expire > 0) 
 | |
| 		if (today > sp->sp_expire) 
 | |
| 		    fatal(s, "Account has expired.");
 | |
| 	}
 | |
|     }
 | |
| #endif
 | |
|     
 | |
| 
 | |
| #ifdef KRB5
 | |
|     {
 | |
| 	int fd;
 | |
|  
 | |
| 	if (!do_unique_tkfile)
 | |
| 	    snprintf(tkfile,sizeof(tkfile),"FILE:/tmp/krb5cc_%u",pwd->pw_uid);
 | |
| 	else if (*tkfile=='\0') {
 | |
| 	    snprintf(tkfile,sizeof(tkfile),"FILE:/tmp/krb5cc_XXXXXX");
 | |
| 	    fd = mkstemp(tkfile+5);
 | |
| 	    close(fd);
 | |
| 	    unlink(tkfile+5);
 | |
| 	}
 | |
|  
 | |
| 	if (kerberos_status)
 | |
| 	    krb5_start_session();
 | |
|     }
 | |
|     chown(tkfile + 5, pwd->pw_uid, -1);
 | |
| 
 | |
| #if defined(DCE)
 | |
|     if (kerberos_status) {
 | |
| 	esetenv("KRB5CCNAME", tkfile, 1);
 | |
| 	dfspag = krb5_dfs_pag(context, kerberos_status, user_ticket->client, server_user);
 | |
|     }
 | |
| #endif
 | |
| 
 | |
| #endif
 | |
| 
 | |
| #ifdef HAVE_SETLOGIN
 | |
|     if (setlogin(pwd->pw_name) < 0)
 | |
| 	syslog(LOG_ERR, "setlogin() failed: %m");
 | |
| #endif
 | |
| 
 | |
| #ifdef HAVE_SETPCRED
 | |
|     if (setpcred (pwd->pw_name, NULL) == -1)
 | |
| 	syslog(LOG_ERR, "setpcred() failure: %m");
 | |
| #endif /* HAVE_SETPCRED */
 | |
| 
 | |
|     if (initgroups (pwd->pw_name, pwd->pw_gid) < 0)
 | |
| 	fatal (s, "Login incorrect.");
 | |
| 
 | |
|     if (setgid(pwd->pw_gid) < 0)
 | |
| 	fatal (s, "Login incorrect.");
 | |
| 
 | |
|     if (setuid (pwd->pw_uid) < 0)
 | |
| 	fatal (s, "Login incorrect.");
 | |
| 
 | |
|     if (chdir (pwd->pw_dir) < 0)
 | |
| 	fatal (s, "Remote directory.");
 | |
| 
 | |
|     if (errsock >= 0) {
 | |
| 	if (dup2 (errsock, STDERR_FILENO) < 0)
 | |
| 	    fatal (s, "Dup2 failed.");
 | |
| 	close (errsock);
 | |
|     }
 | |
| 
 | |
|     setup_environment (&env, pwd);
 | |
| 
 | |
|     if (do_encrypt) {
 | |
| 	setup_copier ();
 | |
|     } else {
 | |
| 	if (net_write (s, "", 1) != 1)
 | |
| 	    fatal (s, "write failed");
 | |
|     }
 | |
| 
 | |
| #ifdef KRB4
 | |
|     if(k_hasafs()) {
 | |
| 	char cell[64];
 | |
| 
 | |
| 	if(do_newpag)
 | |
| 	    k_setpag();
 | |
| 	if (k_afs_cell_of_file (pwd->pw_dir, cell, sizeof(cell)) == 0)
 | |
| 	    krb_afslog_uid_home (cell, NULL, pwd->pw_uid, pwd->pw_dir);
 | |
| 
 | |
| 	krb_afslog_uid_home(NULL, NULL, pwd->pw_uid, pwd->pw_dir);
 | |
| 
 | |
| #ifdef KRB5
 | |
| 	/* XXX */
 | |
|        if (kerberos_status) {
 | |
| 	   krb5_ccache ccache;
 | |
| 	   krb5_error_code status;
 | |
| 
 | |
| 	   status = krb5_cc_resolve (context, tkfile, &ccache);
 | |
| 	   if (!status) {
 | |
| 	       krb5_afslog_uid_home(context,ccache,NULL,NULL,
 | |
| 				    pwd->pw_uid, pwd->pw_dir);
 | |
| 	       krb5_cc_close (context, ccache);
 | |
| 	   }
 | |
|        }
 | |
| #endif /* KRB5 */
 | |
|     }
 | |
| #endif /* KRB4 */
 | |
|     execle (pwd->pw_shell, pwd->pw_shell, "-c", cmd, NULL, env);
 | |
|     err(1, "exec %s", pwd->pw_shell);
 | |
| }
 | |
| 
 | |
| struct getargs args[] = {
 | |
|     { "inetd",		'i',	arg_negative_flag,	&do_inetd,
 | |
|       "Not started from inetd" },
 | |
|     { "kerberos",	'k',	arg_flag,	&do_kerberos,
 | |
|       "Implement kerberised services" },
 | |
|     { "encrypt",	'x',	arg_flag,		&do_encrypt,
 | |
|       "Implement encrypted service" },
 | |
|     { "rhosts",		'l',	arg_flag, &do_rhosts,
 | |
|       "Check users .rhosts" },
 | |
|     { "port",		'p',	arg_string,	&port_str,	"Use this port",
 | |
|       "port" },
 | |
|     { "vacuous",	'v',	arg_flag, &do_vacuous,
 | |
|       "Don't accept non-kerberised connections" },
 | |
|     { NULL,		'P',	arg_negative_flag, &do_newpag,
 | |
|       "Don't put process in new PAG" },
 | |
|     /* compatibility flag: */
 | |
|     { NULL,		'L',	arg_flag, &do_log },
 | |
|     { "version",	0, 	arg_flag,		&do_version },
 | |
|     { "help",		0, 	arg_flag,		&do_help }
 | |
| };
 | |
| 
 | |
| static void
 | |
| usage (int ret)
 | |
| {
 | |
|     if(isatty(STDIN_FILENO))
 | |
| 	arg_printusage (args,
 | |
| 			sizeof(args) / sizeof(args[0]),
 | |
| 			NULL,
 | |
| 			"");
 | |
|     else
 | |
| 	syslog (LOG_ERR, "Usage: %s [-ikxlvPL] [-p port]", getprogname());
 | |
|     exit (ret);
 | |
| }
 | |
| 
 | |
| 
 | |
| int
 | |
| main(int argc, char **argv)
 | |
| {
 | |
|     int optind = 0;
 | |
|     int port = 0;
 | |
| 
 | |
|     setprogname (argv[0]);
 | |
|     roken_openlog ("rshd", LOG_ODELAY | LOG_PID, LOG_AUTH);
 | |
| 
 | |
|     if (getarg(args, sizeof(args) / sizeof(args[0]), argc, argv,
 | |
| 	       &optind))
 | |
| 	usage(1);
 | |
| 
 | |
|     if(do_help)
 | |
| 	usage (0);
 | |
| 
 | |
|     if (do_version) {
 | |
| 	print_version(NULL);
 | |
| 	exit(0);
 | |
|     }
 | |
| 
 | |
| #ifdef KRB5
 | |
|     {
 | |
| 	krb5_error_code ret;
 | |
| 
 | |
| 	ret = krb5_init_context (&context);
 | |
| 	if (ret)
 | |
| 	    errx (1, "krb5_init_context failed: %d", ret);
 | |
|     }	
 | |
| #endif
 | |
| 
 | |
|     if(port_str) {
 | |
| 	struct servent *s = roken_getservbyname (port_str, "tcp");
 | |
| 
 | |
| 	if (s)
 | |
| 	    port = s->s_port;
 | |
| 	else {
 | |
| 	    char *ptr;
 | |
| 
 | |
| 	    port = strtol (port_str, &ptr, 10);
 | |
| 	    if (port == 0 && ptr == port_str)
 | |
| 		syslog_and_die("Bad port `%s'", port_str);
 | |
| 	    port = htons(port);
 | |
| 	}
 | |
|     }
 | |
| 
 | |
|     if (do_encrypt)
 | |
| 	do_kerberos = 1;
 | |
| 
 | |
|     if (!do_inetd) {
 | |
| 	if (port == 0) {
 | |
| 	    if (do_kerberos) {
 | |
| 		if (do_encrypt)
 | |
| 		    port = krb5_getportbyname (context, "ekshell", "tcp", 545);
 | |
| 		else
 | |
| 		    port = krb5_getportbyname (context, "kshell",  "tcp", 544);
 | |
| 	    } else {
 | |
| 		port = krb5_getportbyname(context, "shell", "tcp", 514);
 | |
| 	    }
 | |
| 	}
 | |
| 	mini_inetd (port);
 | |
|     }
 | |
| 
 | |
|     signal (SIGPIPE, SIG_IGN);
 | |
| 
 | |
|     doit (do_kerberos, do_rhosts);
 | |
|     return 0;
 | |
| }
 |