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/* $OpenBSD: skeyinit.c,v 1.7 1996/09/29 04:34:08 millert Exp $ */
/* $NetBSD: skeyinit.c,v 1.6 1995/06/05 19:50:48 pk Exp $ */
/* S/KEY v1.1b (skeyinit.c)
*
* Authors:
* Neil M. Haller <nmh@thumper.bellcore.com>
* Philip R. Karn <karn@chicago.qualcomm.com>
* John S. Walden <jsw@thumper.bellcore.com>
* Scott Chasin <chasin@crimelab.com>
*
* S/KEY initialization and seed update
*/
#include <sys/param.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <err.h>
#include <pwd.h>
#include <unistd.h>
#include <time.h>
#include <utmp.h>
#include <ctype.h>
#include <skey.h>
#ifndef SKEY_MAXSEQ
#define SKEY_MAXSEQ 10000
#endif
#ifndef SKEY_NAMELEN
#define SKEY_NAMELEN 4
#endif
#ifndef SKEY_MIN_PW_LEN
#define SKEY_MIN_PW_LEN 4
#endif
int
main(argc, argv)
int argc;
char *argv[];
{
int rval, n, nn, i, l, md=0, defaultsetup=1, zerokey=0, hexmode=0;
time_t now;
char hostname[MAXHOSTNAMELEN];
char seed[18], tmp[80], key[8], defaultseed[17];
char passwd[256], passwd2[256], tbuf[27], buf[60];
char lastc, me[UT_NAMESIZE+1], *salt, *p, *pw;
struct skey skey;
struct passwd *pp;
struct tm *tm;
if (geteuid() != 0)
errx(1, "must be setuid root.");
(void)time(&now);
(void)sprintf(tbuf, "%05ld", (long) (now % 100000));
if (gethostname(hostname, sizeof(hostname)) < 0)
err(1, "gethostname");
(void)strncpy(defaultseed, hostname, sizeof(defaultseed) - 1);
defaultseed[SKEY_NAMELEN] = '\0';
(void)strncat(defaultseed, tbuf, sizeof(defaultseed) - 5);
if ((pp = getpwuid(getuid())) == NULL)
err(1, "no user with uid %d", getuid());
(void)strcpy(me, pp->pw_name);
if ((pp = getpwnam(me)) == NULL)
err(1, "Who are you?");
while ((i = getopt(argc, argv, "sxz45")) != EOF) {
switch (i) {
case 's':
defaultsetup = 0;
break;
case 'x':
hexmode = 1;
break;
case 'z':
zerokey = 1;
break;
case '4':
md = 4;
break;
case '5':
md = 5;
break;
}
}
/* check for md4/md5 argument */
if (argv[optind]) {
if (strcmp(argv[optind], "MD4") == 0) {
md = 4;
optind++;
} else if (strcmp(argv[optind], "MD5") == 0) {
md = 5;
optind++;
}
}
/* check for optional user string */
if (argc - optind > 1) {
(void)fprintf(stderr,
"Usage: %s [-s] [-x] [-z] [-4|-5] [MD4|MD5] [user]\n",
argv[0]);
exit(1);
} else if (argv[optind]) {
if ((pp = getpwnam(argv[optind])) == NULL)
err(1, "User unknown");
if (strcmp(pp->pw_name, me) != 0) {
if (getuid() != 0) {
/* Only root can change other's passwds */
errx(1, "Permission denied.");
}
}
}
salt = pp->pw_passwd;
(void)setpriority(PRIO_PROCESS, 0, -4);
if (getuid() != 0) {
(void)setpriority(PRIO_PROCESS, 0, -4);
pw = getpass("Password:");
p = crypt(pw, salt);
(void)setpriority(PRIO_PROCESS, 0, 0);
if (pp && strcmp(p, pp->pw_passwd))
errx(1, "Password incorrect.");
}
rval = skeylookup(&skey, pp->pw_name);
switch (rval) {
case -1:
err(1, "cannot open database");
case 0:
/* comment out user if asked to */
if (zerokey)
exit(skeyzero(&skey, pp->pw_name));
(void)printf("[Updating %s]\n", pp->pw_name);
(void)printf("Old key: %s\n", skey.seed);
/*
* Lets be nice if they have a skey.seed that
* ends in 0-8 just add one
*/
l = strlen(skey.seed);
if (l > 0) {
lastc = skey.seed[l - 1];
if (isdigit(lastc) && lastc != '9') {
(void)strcpy(defaultseed, skey.seed);
defaultseed[l - 1] = lastc + 1;
}
if (isdigit(lastc) && lastc == '9' && l < 16) {
(void)strcpy(defaultseed, skey.seed);
defaultseed[l - 1] = '0';
defaultseed[l] = '0';
defaultseed[l + 1] = '\0';
}
}
break;
case 1:
if (zerokey)
errx(1, "You have no entry to zero.");
(void)printf("[Adding %s]\n", pp->pw_name);
break;
}
n = 99;
/* Set MDX (currently 4 or 5) if given the option */
if (md)
skey_set_MDX(md);
if (!defaultsetup) {
(void)printf("You need the 6 english words generated from the \"skey\" command.\n");
for (i = 0;; i++) {
if (i >= 2)
exit(1);
(void)printf("Enter sequence count from 1 to %d: ",
SKEY_MAXSEQ);
(void)fgets(tmp, sizeof(tmp), stdin);
n = atoi(tmp);
if (n > 0 && n < SKEY_MAXSEQ)
break; /* Valid range */
(void)printf("\n Error: Count must be > 0 and < %d\n",
SKEY_MAXSEQ);
}
(void)printf("Enter new key [default %s]: ", defaultseed);
(void)fflush(stdout);
(void)fgets(seed, sizeof(seed), stdin);
rip(seed);
if (strlen(seed) > 16) {
(void)puts("Notice: Seed truncated to 16 characters.");
seed[16] = '\0';
}
if (seed[0] == '\0')
(void)strcpy(seed, defaultseed);
for (i = 0;; i++) {
if (i >= 2)
exit(1);
(void)printf("skey %d %s\nskey access password: ",
n, seed);
(void)fgets(tmp, sizeof(tmp), stdin);
rip(tmp);
backspace(tmp);
if (tmp[0] == '?') {
(void)puts("Enter 6 English words from secure S/Key calculation.");
continue;
} else if (tmp[0] == '\0')
exit(1);
if (etob(key, tmp) == 1 || atob8(key, tmp) == 0)
break; /* Valid format */
(void)puts("Invalid format - try again with 6 English words.");
}
} else {
/* Get user's secret password */
fputs("Reminder - Only use this method if you are directly connected\n or have an encrypted channel. If you are using telnet\n or rlogin, exit with no password and use keyinit -s.\n", stderr);
for (i = 0;; i++) {
if (i > 2)
exit(1);
(void)fputs("Enter secret password: ", stderr);
readpass(passwd, sizeof(passwd));
if (passwd[0] == '\0')
exit(1);
if (strlen(passwd) < SKEY_MIN_PW_LEN) {
(void)fputs("Your password must be longer.\n",
stderr);
continue;
}
(void)fputs("Again secret password: ", stderr);
readpass(passwd2, sizeof(passwd));
if (passwd2[0] == '\0')
exit(1);
if (strcmp(passwd, passwd2) == 0)
break;
(void)fputs("Passwords do not match.\n", stderr);
}
/* Crunch seed and password into starting key */
(void)strcpy(seed, defaultseed);
if (keycrunch(key, seed, passwd) != 0)
err(2, "key crunch failed");
nn = n;
while (nn-- != 0)
f(key);
}
(void)time(&now);
tm = localtime(&now);
(void)strftime(tbuf, sizeof(tbuf), " %b %d,%Y %T", tm);
if ((skey.val = (char *)malloc(16 + 1)) == NULL)
err(1, "Can't allocate memory");
btoa8(skey.val, key);
(void)fprintf(skey.keyfile, "%s MD%d %04d %-16s %s %-21s\n",
pp->pw_name, skey_get_MDX(), n, seed, skey.val, tbuf);
(void)fclose(skey.keyfile);
(void)printf("\nID %s skey is %d %s\n", pp->pw_name, n, seed);
(void)printf("Next login password: %s\n", hexmode ? put8(buf, key) : btoe(buf, key));
exit(0);
}
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