Annotation of src/usr.bin/passwd/local_passwd.c, Revision 1.42
1.42 ! tedu 1: /* $OpenBSD: local_passwd.c,v 1.41 2013/01/18 11:13:38 guenther Exp $ */
1.3 deraadt 2:
1.1 deraadt 3: /*-
4: * Copyright (c) 1990 The Regents of the University of California.
5: * All rights reserved.
6: *
7: * Redistribution and use in source and binary forms, with or without
8: * modification, are permitted provided that the following conditions
9: * are met:
10: * 1. Redistributions of source code must retain the above copyright
11: * notice, this list of conditions and the following disclaimer.
12: * 2. Redistributions in binary form must reproduce the above copyright
13: * notice, this list of conditions and the following disclaimer in the
14: * documentation and/or other materials provided with the distribution.
1.29 millert 15: * 3. Neither the name of the University nor the names of its contributors
1.1 deraadt 16: * may be used to endorse or promote products derived from this software
17: * without specific prior written permission.
18: *
19: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29: * SUCH DAMAGE.
30: */
31:
32: #include <sys/types.h>
1.2 deraadt 33: #include <sys/stat.h>
1.21 millert 34: #include <sys/uio.h>
35:
1.7 weingart 36: #include <err.h>
1.1 deraadt 37: #include <errno.h>
1.21 millert 38: #include <fcntl.h>
39: #include <pwd.h>
1.1 deraadt 40: #include <stdio.h>
1.28 deraadt 41: #include <stdlib.h>
1.21 millert 42: #include <signal.h>
1.1 deraadt 43: #include <string.h>
1.2 deraadt 44: #include <unistd.h>
45: #include <util.h>
1.14 millert 46: #include <login_cap.h>
1.1 deraadt 47:
1.27 millert 48: #define UNCHANGED_MSG "Password unchanged.\n"
49:
1.7 weingart 50: static uid_t uid;
1.33 millert 51: extern int pwd_gensalt(char *, int, login_cap_t *, char);
52: extern int pwd_check(login_cap_t *, char *);
53: extern int pwd_gettries(login_cap_t *);
1.14 millert 54:
1.39 djm 55: int local_passwd(char *, int);
1.25 millert 56: char *getnewpasswd(struct passwd *, login_cap_t *, int);
57: void kbintr(int);
1.1 deraadt 58:
1.7 weingart 59: int
1.26 deraadt 60: local_passwd(char *uname, int authenticated)
1.1 deraadt 61: {
1.32 millert 62: struct passwd *pw, *opw;
1.14 millert 63: login_cap_t *lc;
1.15 millert 64: sigset_t fullset;
65: time_t period;
1.21 millert 66: int i, pfd, tfd = -1;
1.20 millert 67: int pwflags = _PASSWORD_OMITV7;
1.1 deraadt 68:
69: if (!(pw = getpwnam(uname))) {
70: #ifdef YP
71: extern int use_yp;
72: if (!use_yp)
73: #endif
1.7 weingart 74: warnx("unknown user %s.", uname);
1.1 deraadt 75: return(1);
76: }
1.32 millert 77: if ((opw = pw_dup(pw)) == NULL) {
78: warn(NULL);
79: return(1);
80: }
1.14 millert 81: if ((lc = login_getclass(pw->pw_class)) == NULL) {
82: warnx("unable to get login class for user %s.", uname);
1.36 moritz 83: free(opw);
1.14 millert 84: return(1);
85: }
1.1 deraadt 86:
1.13 millert 87: uid = authenticated ? pw->pw_uid : getuid();
1.1 deraadt 88: if (uid && uid != pw->pw_uid) {
1.8 millert 89: warnx("login/uid mismatch, username argument required.");
1.36 moritz 90: free(opw);
1.1 deraadt 91: return(1);
92: }
93:
1.14 millert 94: /* Get the new password. */
95: pw->pw_passwd = getnewpasswd(pw, lc, authenticated);
96:
97: /* Reset password change time based on login.conf. */
1.30 deraadt 98: period = (time_t)login_getcaptime(lc, "passwordtime",
99: (quad_t)0, (quad_t)0);
1.19 millert 100: if (period > 0) {
1.14 millert 101: pw->pw_change = time(NULL) + period;
1.19 millert 102: } else {
103: /*
104: * If the pw change time is the same we only need
105: * to update the spwd.db file.
106: */
107: if (pw->pw_change != 0)
108: pw->pw_change = 0;
109: else
1.20 millert 110: pwflags = _PASSWORD_SECUREONLY;
1.19 millert 111: }
1.14 millert 112:
1.15 millert 113: /* Drop user's real uid and block all signals to avoid a DoS. */
114: setuid(0);
115: sigfillset(&fullset);
116: sigdelset(&fullset, SIGINT);
117: sigprocmask(SIG_BLOCK, &fullset, NULL);
118:
119: /* Get a lock on the passwd file and open it. */
120: pw_init();
1.21 millert 121: for (i = 1; (tfd = pw_lock(0)) == -1; i++) {
122: if (i == 4)
1.38 jsing 123: (void)fputs("Attempting to lock password file, "
1.21 millert 124: "please wait or press ^C to abort", stderr);
125: (void)signal(SIGINT, kbintr);
126: if (i % 16 == 0)
1.15 millert 127: fputc('.', stderr);
1.21 millert 128: usleep(250000);
1.15 millert 129: (void)signal(SIGINT, SIG_IGN);
130: }
1.21 millert 131: if (i >= 4)
132: fputc('\n', stderr);
1.41 guenther 133: pfd = open(_PATH_MASTERPASSWD, O_RDONLY | O_CLOEXEC, 0);
134: if (pfd < 0)
1.15 millert 135: pw_error(_PATH_MASTERPASSWD, 1, 1);
136:
1.18 millert 137: /* Update master.passwd file and rebuild spwd.db. */
1.32 millert 138: pw_copy(pfd, tfd, pw, opw);
139: free(opw);
1.20 millert 140: if (pw_mkdb(uname, pwflags) < 0)
1.19 millert 141: pw_error(NULL, 0, 1);
1.14 millert 142:
1.1 deraadt 143: return(0);
144: }
145:
146: char *
1.26 deraadt 147: getnewpasswd(struct passwd *pw, login_cap_t *lc, int authenticated)
1.1 deraadt 148: {
1.22 mpech 149: char *p;
1.11 provos 150: int tries, pwd_tries;
1.13 millert 151: char buf[_PASSWORD_LEN+1], salt[_PASSWORD_LEN];
1.24 millert 152: sig_t saveint, savequit;
1.1 deraadt 153:
1.24 millert 154: saveint = signal(SIGINT, kbintr);
155: savequit = signal(SIGQUIT, kbintr);
1.23 millert 156:
1.13 millert 157: if (!authenticated) {
158: (void)printf("Changing local password for %s.\n", pw->pw_name);
1.27 millert 159: if (uid != 0 && pw->pw_passwd[0] != '\0') {
160: p = getpass("Old password:");
1.31 millert 161: if (p == NULL || *p == '\0') {
1.27 millert 162: (void)printf(UNCHANGED_MSG);
163: pw_abort();
1.31 millert 164: exit(p == NULL ? 1 : 0);
1.27 millert 165: }
1.42 ! tedu 166: if (crypt_checkpass(p, pw->pw_passwd) != 0) {
1.27 millert 167: errno = EACCES;
168: pw_error(NULL, 1, 1);
169: }
1.13 millert 170: }
1.1 deraadt 171: }
1.26 deraadt 172:
1.33 millert 173: pwd_tries = pwd_gettries(lc);
1.1 deraadt 174:
175: for (buf[0] = '\0', tries = 0;;) {
176: p = getpass("New password:");
1.31 millert 177: if (p == NULL || *p == '\0') {
1.27 millert 178: (void)printf(UNCHANGED_MSG);
179: pw_abort();
1.31 millert 180: exit(p == NULL ? 1 : 0);
1.9 deraadt 181: }
182: if (strcmp(p, "s/key") == 0) {
183: printf("That password collides with a system feature. Choose another.\n");
184: continue;
1.1 deraadt 185: }
1.26 deraadt 186:
1.37 deraadt 187: if ((tries++ < pwd_tries || pwd_tries == 0) &&
188: pwd_check(lc, p) == 0)
1.1 deraadt 189: continue;
1.13 millert 190: strlcpy(buf, p, sizeof(buf));
1.31 millert 191: p = getpass("Retype new password:");
192: if (p != NULL && strcmp(buf, p) == 0)
1.1 deraadt 193: break;
194: (void)printf("Mismatch; try again, EOF to quit.\n");
195: }
1.33 millert 196: if (!pwd_gensalt(salt, _PASSWORD_LEN, lc, 'l')) {
1.6 provos 197: (void)printf("Couldn't generate salt.\n");
198: pw_error(NULL, 0, 0);
199: }
1.24 millert 200: (void)signal(SIGINT, saveint);
201: (void)signal(SIGQUIT, savequit);
1.23 millert 202:
1.1 deraadt 203: return(crypt(buf, salt));
1.15 millert 204: }
205:
1.35 deraadt 206: /* ARGSUSED */
1.15 millert 207: void
1.26 deraadt 208: kbintr(int signo)
1.15 millert 209: {
1.34 millert 210: write(STDOUT_FILENO, "\n", 1);
1.27 millert 211: write(STDOUT_FILENO, UNCHANGED_MSG, sizeof(UNCHANGED_MSG) - 1);
212: _exit(0);
1.1 deraadt 213: }