1 /*
2  * Copyright (c) 1996, 1998-2002 Todd C. Miller <Todd.Miller@courtesan.com>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  *
16  * Sponsored in part by the Defense Advanced Research Projects
17  * Agency (DARPA) and Air Force Research Laboratory, Air Force
18  * Materiel Command, USAF, under agreement number F39502-99-1-0512.
19  */
20 
21 #include "config.h"
22 
23 #include <sys/types.h>
24 #include <sys/stat.h>
25 #include <sys/param.h>
26 #include <stdio.h>
27 #ifdef STDC_HEADERS
28 # include <stdlib.h>
29 # include <stddef.h>
30 #else
31 # ifdef HAVE_STDLIB_H
32 #  include <stdlib.h>
33 # endif
34 #endif /* STDC_HEADERS */
35 #ifdef HAVE_STRING_H
36 # if defined(HAVE_MEMORY_H) && !defined(STDC_HEADERS)
37 #  include <memory.h>
38 # endif
39 # include <string.h>
40 #else
41 # ifdef HAVE_STRINGS_H
42 #  include <strings.h>
43 # endif
44 #endif /* HAVE_STRING_H */
45 #ifdef HAVE_UNISTD_H
46 # include <unistd.h>
47 #endif /* HAVE_UNISTD_H */
48 #include <pwd.h>
49 #ifdef HAVE_GETSPNAM
50 # include <shadow.h>
51 #endif /* HAVE_GETSPNAM */
52 #ifdef HAVE_GETPRPWNAM
53 # ifdef __hpux
54 #  undef MAXINT
55 #  include <hpsecurity.h>
56 # else
57 #  include <sys/security.h>
58 # endif /* __hpux */
59 # include <prot.h>
60 #endif /* HAVE_GETPRPWNAM */
61 #ifdef HAVE_GETPWANAM
62 # include <sys/label.h>
63 # include <sys/audit.h>
64 # include <pwdadj.h>
65 #endif /* HAVE_GETPWANAM */
66 #ifdef HAVE_GETAUTHUID
67 # include <auth.h>
68 #endif /* HAVE_GETAUTHUID */
69 
70 #include "sudo.h"
71 
72 #ifndef lint
73 static const char rcsid[] = "$Sudo: getspwuid.c,v 1.65 2004/02/13 21:36:43 millert Exp $";
74 #endif /* lint */
75 
76 /*
77  * Global variables (yuck)
78  */
79 #if defined(HAVE_GETPRPWNAM) && defined(__alpha)
80 int crypt_type = INT_MAX;
81 #endif /* HAVE_GETPRPWNAM && __alpha */
82 
83 
84 /*
85  * Return a copy of the encrypted password for the user described by pw.
86  * If shadow passwords are in use, look in the shadow file.
87  */
88 char *
sudo_getepw(pw)89 sudo_getepw(pw)
90     const struct passwd *pw;
91 {
92     char *epw;
93 
94     /* If there is a function to check for shadow enabled, use it... */
95 #ifdef HAVE_ISCOMSEC
96     if (!iscomsec())
97 	return(estrdup(pw->pw_passwd));
98 #endif /* HAVE_ISCOMSEC */
99 #ifdef HAVE_ISSECURE
100     if (!issecure())
101 	return(estrdup(pw->pw_passwd));
102 #endif /* HAVE_ISSECURE */
103 
104     epw = NULL;
105 #ifdef HAVE_GETPRPWNAM
106     {
107 	struct pr_passwd *spw;
108 
109 	setprpwent();
110 	if ((spw = getprpwnam(pw->pw_name)) && spw->ufld.fd_encrypt) {
111 # ifdef __alpha
112 	    crypt_type = spw->ufld.fd_oldcrypt;
113 # endif /* __alpha */
114 	    epw = estrdup(spw->ufld.fd_encrypt);
115 	}
116 	endprpwent();
117 	if (epw)
118 	    return(epw);
119     }
120 #endif /* HAVE_GETPRPWNAM */
121 #ifdef HAVE_GETSPNAM
122     {
123 	struct spwd *spw;
124 
125 	setspent();
126 	if ((spw = getspnam(pw->pw_name)) && spw->sp_pwdp)
127 	    epw = estrdup(spw->sp_pwdp);
128 	endspent();
129 	if (epw)
130 	    return(epw);
131     }
132 #endif /* HAVE_GETSPNAM */
133 #ifdef HAVE_GETSPWUID
134     {
135 	struct s_passwd *spw;
136 
137 	setspwent();
138 	if ((spw = getspwuid(pw->pw_uid)) && spw->pw_passwd)
139 	    epw = estrdup(spw->pw_passwd);
140 	endspwent();
141 	if (epw)
142 	    return(epw);
143     }
144 #endif /* HAVE_GETSPWUID */
145 #ifdef HAVE_GETPWANAM
146     {
147 	struct passwd_adjunct *spw;
148 
149 	setpwaent();
150 	if ((spw = getpwanam(pw->pw_name)) && spw->pwa_passwd)
151 	    epw = estrdup(spw->pwa_passwd);
152 	endpwaent();
153 	if (epw)
154 	    return(epw);
155     }
156 #endif /* HAVE_GETPWANAM */
157 #ifdef HAVE_GETAUTHUID
158     {
159 	AUTHORIZATION *spw;
160 
161 	setauthent();
162 	if ((spw = getauthuid(pw->pw_uid)) && spw->a_password)
163 	    epw = estrdup(spw->a_password);
164 	endauthent();
165 	if (epw)
166 	    return(epw);
167     }
168 #endif /* HAVE_GETAUTHUID */
169 
170     /* Fall back on normal password. */
171     return(estrdup(pw->pw_passwd));
172 }
173 
174 /*
175  * Dynamically allocate space for a struct password and the constituent parts
176  * that we care about.  Fills in pw_passwd from shadow file if necessary.
177  */
178 struct passwd *
sudo_pwdup(pw)179 sudo_pwdup(pw)
180     const struct passwd *pw;
181 {
182     char *cp;
183     const char *pw_passwd, *pw_shell;
184     size_t nsize, psize, csize, gsize, dsize, ssize, total;
185     struct passwd *newpw;
186 
187     /* Get shadow password if available. */
188     pw_passwd = sudo_getepw(pw);
189 
190     /* If shell field is empty, expand to _PATH_BSHELL. */
191     pw_shell = (pw->pw_shell == NULL || pw->pw_shell[0] == '\0')
192 	? _PATH_BSHELL : pw->pw_shell;
193 
194     /* Allocate in one big chunk for easy freeing. */
195     nsize = psize = csize = gsize = dsize = ssize = 0;
196     total = sizeof(struct passwd);
197     if (pw->pw_name) {
198 	    nsize = strlen(pw->pw_name) + 1;
199 	    total += nsize;
200     }
201     if (pw_passwd) {
202 	    psize = strlen(pw_passwd) + 1;
203 	    total += psize;
204     }
205 #ifdef HAVE_LOGIN_CAP_H
206     if (pw->pw_class) {
207 	    csize = strlen(pw->pw_class) + 1;
208 	    total += csize;
209     }
210 #endif
211     if (pw->pw_gecos) {
212 	    gsize = strlen(pw->pw_gecos) + 1;
213 	    total += gsize;
214     }
215     if (pw->pw_dir) {
216 	    dsize = strlen(pw->pw_dir) + 1;
217 	    total += dsize;
218     }
219     if (pw_shell) {
220 	    ssize = strlen(pw_shell) + 1;
221 	    total += ssize;
222     }
223     if ((cp = malloc(total)) == NULL)
224 	    return (NULL);
225     newpw = (struct passwd *)cp;
226 
227     /*
228      * Copy in passwd contents and make strings relative to space
229      * at the end of the buffer.
230      */
231     (void)memcpy(newpw, pw, sizeof(struct passwd));
232     cp += sizeof(struct passwd);
233     if (nsize) {
234 	    (void)memcpy(cp, pw->pw_name, nsize);
235 	    newpw->pw_name = cp;
236 	    cp += nsize;
237     }
238     if (psize) {
239 	    (void)memcpy(cp, pw_passwd, psize);
240 	    newpw->pw_passwd = cp;
241 	    cp += psize;
242     }
243 #ifdef HAVE_LOGIN_CAP_H
244     if (csize) {
245 	    (void)memcpy(cp, pw->pw_class, csize);
246 	    newpw->pw_class = cp;
247 	    cp += csize;
248     }
249 #endif
250     if (gsize) {
251 	    (void)memcpy(cp, pw->pw_gecos, gsize);
252 	    newpw->pw_gecos = cp;
253 	    cp += gsize;
254     }
255     if (dsize) {
256 	    (void)memcpy(cp, pw->pw_dir, dsize);
257 	    newpw->pw_dir = cp;
258 	    cp += dsize;
259     }
260     if (ssize) {
261 	    (void)memcpy(cp, pw_shell, ssize);
262 	    newpw->pw_shell = cp;
263 	    cp += ssize;
264     }
265 
266     return (newpw);
267 }
268 
269 /*
270  * Get a password entry by uid and allocate space for it.
271  * Fills in pw_passwd from shadow file if necessary.
272  */
273 struct passwd *
sudo_getpwuid(uid)274 sudo_getpwuid(uid)
275     uid_t uid;
276 {
277     struct passwd *pw;
278 
279     if ((pw = getpwuid(uid)) == NULL)
280 	return(NULL);
281     else
282 	return(sudo_pwdup(pw));
283 }
284 
285 /*
286  * Get a password entry by name and allocate space for it.
287  * Fills in pw_passwd from shadow file if necessary.
288  */
289 struct passwd *
sudo_getpwnam(name)290 sudo_getpwnam(name)
291     const char *name;
292 {
293     struct passwd *pw;
294 
295     if ((pw = getpwnam(name)) == NULL)
296 	return(NULL);
297     else
298 	return(sudo_pwdup(pw));
299 }
300