xref: /freebsd/crypto/heimdal/appl/login/utmp_login.c (revision 6a068746777241722b2b32c5d0bc443a2a64d80b)
1 /*
2  * Copyright (c) 1995 - 2001 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 "login_locl.h"
35 
36 RCSID("$Id$");
37 
38 /* try to put something useful from hostname into dst, dst_sz:
39  * full name, first component or address */
40 
41 void
shrink_hostname(const char * hostname,char * dst,size_t dst_sz)42 shrink_hostname (const char *hostname,
43 		 char *dst, size_t dst_sz)
44 {
45     char local_hostname[MaxHostNameLen];
46     char *ld, *hd;
47     int ret;
48     struct addrinfo *ai;
49 
50     if (strlen(hostname) < dst_sz) {
51 	strlcpy (dst, hostname, dst_sz);
52 	return;
53     }
54     gethostname (local_hostname, sizeof(local_hostname));
55     hd = strchr (hostname, '.');
56     ld = strchr (local_hostname, '.');
57     if (hd != NULL && ld != NULL && strcmp(hd, ld) == 0
58 	&& hd - hostname < dst_sz) {
59 	strlcpy (dst, hostname, dst_sz);
60 	dst[hd - hostname] = '\0';
61 	return;
62     }
63 
64     ret = getaddrinfo (hostname, NULL, NULL, &ai);
65     if (ret) {
66 	strncpy (dst, hostname, dst_sz);
67 	return;
68     }
69     ret = getnameinfo (ai->ai_addr, ai->ai_addrlen,
70 		       dst, dst_sz,
71 		       NULL, 0,
72 		       NI_NUMERICHOST);
73     freeaddrinfo (ai);
74     if (ret) {
75 	strncpy (dst, hostname, dst_sz);
76 	return;
77     }
78 }
79 
80 /* update utmp and wtmp - the BSD way */
81 
82 #if !defined(HAVE_UTMPX_H) || (defined(WTMP_FILE) && !defined(WTMPX_FILE))
83 
84 void
prepare_utmp(struct utmp * utmp,char * tty,const char * username,const char * hostname)85 prepare_utmp (struct utmp *utmp, char *tty,
86 	      const char *username, const char *hostname)
87 {
88     char *ttyx = clean_ttyname (tty);
89 
90     memset(utmp, 0, sizeof(*utmp));
91     utmp->ut_time = time(NULL);
92     strncpy(utmp->ut_line, ttyx, sizeof(utmp->ut_line));
93     strncpy(utmp->ut_name, username, sizeof(utmp->ut_name));
94 
95 # ifdef HAVE_STRUCT_UTMP_UT_USER
96     strncpy(utmp->ut_user, username, sizeof(utmp->ut_user));
97 # endif
98 
99 # ifdef HAVE_STRUCT_UTMP_UT_ADDR
100     if (hostname[0]) {
101         struct hostent *he;
102 	if ((he = gethostbyname(hostname)))
103 	    memcpy(&utmp->ut_addr, he->h_addr_list[0],
104 		   sizeof(utmp->ut_addr));
105     }
106 # endif
107 
108 # ifdef HAVE_STRUCT_UTMP_UT_HOST
109     shrink_hostname (hostname, utmp->ut_host, sizeof(utmp->ut_host));
110 # endif
111 
112 # ifdef HAVE_STRUCT_UTMP_UT_TYPE
113     utmp->ut_type = USER_PROCESS;
114 # endif
115 
116 # ifdef HAVE_STRUCT_UTMP_UT_PID
117     utmp->ut_pid = getpid();
118 # endif
119 
120 # ifdef HAVE_STRUCT_UTMP_UT_ID
121     strncpy(utmp->ut_id, make_id(ttyx), sizeof(utmp->ut_id));
122 # endif
123 }
124 #endif
125 
126 #ifdef HAVE_UTMPX_H
utmp_login(char * tty,const char * username,const char * hostname)127 void utmp_login(char *tty, const char *username, const char *hostname)
128 {
129     return;
130 }
131 #else
132 
utmp_login(char * tty,const char * username,const char * hostname)133 void utmp_login(char *tty, const char *username, const char *hostname)
134 {
135     struct utmp utmp;
136     int fd;
137 
138     prepare_utmp (&utmp, tty, username, hostname);
139 
140 #ifdef HAVE_SETUTENT
141     utmpname(_PATH_UTMP);
142     setutent();
143     pututline(&utmp);
144     endutent();
145 #else
146 
147 #ifdef HAVE_TTYSLOT
148     {
149       int ttyno;
150       ttyno = ttyslot();
151       if (ttyno > 0 && (fd = open(_PATH_UTMP, O_WRONLY, 0)) >= 0) {
152 	lseek(fd, (long)(ttyno * sizeof(struct utmp)), SEEK_SET);
153 	write(fd, &utmp, sizeof(struct utmp));
154 	close(fd);
155       }
156     }
157 #endif /* HAVE_TTYSLOT */
158 #endif /* HAVE_SETUTENT */
159 
160     if ((fd = open(_PATH_WTMP, O_WRONLY|O_APPEND, 0)) >= 0) {
161 	write(fd, &utmp, sizeof(struct utmp));
162 	close(fd);
163     }
164 }
165 
166 #endif /* !HAVE_UTMPX_H */
167