===================================================================
RCS file: /cvsrepo/anoncvs/cvs/src/usr.bin/skeyinit/skeyinit.c,v
retrieving revision 1.27
retrieving revision 1.28
diff -u -r1.27 -r1.28
--- src/usr.bin/skeyinit/skeyinit.c	2001/01/26 16:27:04	1.27
+++ src/usr.bin/skeyinit/skeyinit.c	2001/06/20 22:25:08	1.28
@@ -1,17 +1,15 @@
-/*	$OpenBSD: skeyinit.c,v 1.27 2001/01/26 16:27:04 millert Exp $	*/
+/*	$OpenBSD: skeyinit.c,v 1.28 2001/06/20 22:25:08 millert Exp $	*/
 
-/* S/KEY v1.1b (skeyinit.c)
+/* OpenBSD S/Key (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>
- *
- * Modifications:
  *          Todd C. Miller <Todd.Miller@courtesan.com>
  *
- * S/KEY initialization and seed update
+ * S/Key initialization and seed update
  */
 
 #include <sys/param.h>
@@ -23,6 +21,7 @@
 #include <errno.h>
 #include <ctype.h>
 #include <pwd.h>
+#include <readpassphrase.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -37,20 +36,26 @@
 #define SKEY_NAMELEN    4
 #endif
 
+void	lockeof __P((struct skey *, char *));
 void	usage __P((char *));
+void	secure_mode __P((int *, char *, char *, char *, char *, size_t));
+void	normal_mode __P((char *, int, char *, char *, char *));
+void	timedout __P((int));
 
 int
 main(argc, argv)
 	int     argc;
 	char   *argv[];
 {
-	int     rval, nn, i, l, n=0, defaultsetup=1, zerokey=0, hexmode=0;
+	int     rval, i, l, n=0, defaultsetup=1, zerokey=0, hexmode=0;
+	int	oldmd4=0;
 	time_t  now;
+	size_t	seedlen;
 	char	hostname[MAXHOSTNAMELEN];
-	char    passwd[SKEY_MAX_PW_LEN+2], passwd2[SKEY_MAX_PW_LEN+2];
+	char    passwd[SKEY_MAX_PW_LEN+2];
 	char	seed[SKEY_MAX_SEED_LEN+2], defaultseed[SKEY_MAX_SEED_LEN+1];
-	char    tbuf[27], buf[80], key[SKEY_BINKEY_SIZE];
-	char    lastc, me[UT_NAMESIZE+1], *salt, *p, *pw, *ht=NULL;
+	char    tbuf[27], buf[256], key[SKEY_BINKEY_SIZE];
+	char    lastc, me[UT_NAMESIZE+1], *salt, *p, *ht=NULL;
 	struct skey skey;
 	struct passwd *pp;
 	struct tm *tm;
@@ -58,6 +63,7 @@
 	if (geteuid() != 0)
 		errx(1, "must be setuid root.");
 
+	/* Build up a default seed based on the hostname and time */
 	if (gethostname(hostname, sizeof(hostname)) < 0)
 		err(1, "gethostname");
 	for (i = 0, p = defaultseed; hostname[i] && i < SKEY_NAMELEN; i++) {
@@ -136,20 +142,41 @@
 		}
 	}
 
+	if (defaultsetup)
+		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, hit return now and use skeyinit -s.\n", stderr);
+
 	if (getuid() != 0) {
-		pw = getpass("Password (or `s/key'):");
-		if (strcasecmp(pw, "s/key") == 0) {
-			if (skey_haskey(me))
-				exit(1);
-			if (skey_authenticate(me))
+		/* XXX - use BSD auth */
+		passwd[0] = '\0';
+		if (!defaultsetup && skeychallenge(&skey, me, buf) == 0) {
+			printf("Enter S/Key password below or hit return twice "
+			    "to enter standard password.\n%s\n", buf);
+			fflush(stdout);
+			if (!readpassphrase("S/Key Password: ", passwd,
+			    sizeof(passwd), 0) || passwd[0] == '\0') {
+				readpassphrase("S/Key Password: [echo on] ",
+				    passwd, sizeof(passwd), RPP_ECHO_ON);
+			}
+		}
+		if (passwd[0]) {
+			if (skeyverify(&skey, passwd) != 0)
 				errx(1, "Password incorrect.");
 		} else {
-			p = crypt(pw, salt);
-			if (strcmp(p, pp->pw_passwd))
-				errx(1, "Password incorrect.");
+			fflush(stdout);
+			readpassphrase("Password: ", passwd, sizeof(passwd), 0);
+			if (strcmp(crypt(passwd, salt), pp->pw_passwd)) {
+				if (passwd[0])
+					warnx("Password incorrect.");
+				exit(1);
+			}
 		}
 	}
 
+	/*
+	 * Lookup and lock the record we are about to modify.
+	 * If this is a new entry this will prevent other users
+	 * from appending new entries (and clobbering ours).
+	 */
 	rval = skeylookup(&skey, pp->pw_name);
 	switch (rval) {
 		case -1:
@@ -163,9 +190,10 @@
 			if (zerokey)
 				exit(skeyzero(&skey, pp->pw_name));
 
-			(void)printf("[Updating %s]\n", pp->pw_name);
-			(void)printf("Old key: [%s] %s\n", skey_get_algorithm(),
-				     skey.seed);
+			(void)printf("[Updating %s with %s]\n", pp->pw_name,
+			    ht ? ht : skey_get_algorithm());
+			(void)printf("Old seed: [%s] %s\n",
+				     skey_get_algorithm(), skey.seed);
 
 			/*
 			 * Sanity check old seed.
@@ -181,10 +209,7 @@
 				}
 			}
 
-			/*
-			 * Let's be nice if they have an skey.seed that
-			 * ends in 0-8 just add one
-			 */
+			/* If the seed ends in 0-8 just add one.  */
 			if (l > 0) {
 				lastc = skey.seed[l - 1];
 				if (isdigit(lastc) && lastc != '9') {
@@ -202,172 +227,270 @@
 		case 1:
 			if (zerokey)
 				errx(1, "You have no entry to zero.");
-			(void)printf("[Adding %s]\n", pp->pw_name);
+			(void)printf("[Adding %s with %s]\n", pp->pw_name,
+			    ht ? ht : skey_get_algorithm());
+			lockeof(&skey, pp->pw_name);
 			break;
 	}
 	if (n == 0)
 		n = 99;
 
+	/* Do we have an old-style md4 entry? */
+	if (rval == 0 && strcmp("md4", skey_get_algorithm()) == 0 &&
+	    strcmp("md4", skey.logname + strlen(skey.logname) + 1) != 0)
+		oldmd4 = 1;
+
 	/* Set hash type if asked to */
-	if (ht) {
-		/* Need to zero out old key when changing algorithm */
-		if (strcmp(ht, skey_get_algorithm()) && skey_set_algorithm(ht))
-			zerokey = 1;
-	}
+	if (ht && strcmp(ht, skey_get_algorithm()) != 0)
+		skey_set_algorithm(ht);
 
-	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);
+	alarm(180);
+	if (!defaultsetup)
+		secure_mode(&n, key, seed, defaultseed, buf, sizeof(buf));
+	else
+		normal_mode(pp->pw_name, n, key, seed, defaultseed);
+	alarm(0);
 
-			(void)printf("Enter sequence count from 1 to %d: ",
-				     SKEY_MAX_SEQ);
-			(void)fgets(buf, sizeof(buf), stdin);
-			n = atoi(buf);
-			if (n > 0 && n < SKEY_MAX_SEQ)
-				break;	/* Valid range */
-			(void)printf("Error: Count must be > 0 and < %d\n",
-				     SKEY_MAX_SEQ);
-		}
+	(void)time(&now);
+	tm = localtime(&now);
+	(void)strftime(tbuf, sizeof(tbuf), " %b %d,%Y %T", tm);
 
-		for (i = 0;; i++) {
-			if (i >= 2)
-				exit(1);
+	/* If this is an exiting entry, compute the line length and seed pad */
+	seedlen = SKEY_MAX_SEED_LEN;
+	if (rval == 0) {
+		int nlen;
 
-			(void)printf("Enter new key [default %s]: ",
-				     defaultseed);
-			(void)fgets(seed, sizeof(seed), stdin);
-			rip(seed);
-			if (seed[0] == '\0')
-				(void)strcpy(seed, defaultseed);
-			for (p = seed; *p; p++) {
-				if (isalpha(*p)) {
-					if (isupper(*p))
-						*p = tolower(*p);
-				} else if (!isdigit(*p)) {
-					(void)puts("Error: seed may only contain alpha numeric characters");
-					break;
-				}
-			}
-			if (*p == '\0')
-				break;  /* Valid seed */
+		nlen = strlen(pp->pw_name) + 1 + strlen(skey_get_algorithm()) +
+		    1 + 4 + 1 + strlen(seed) + 1 + 16 + 1 + strlen(tbuf) + 1;
+
+		/*
+		 * If there was no hash type (md4) add one unless we
+		 * are short on space.
+		 */ 
+		if (oldmd4) {
+			if (nlen > skey.len)
+				nlen -= 4;
+			else
+				oldmd4 = 0;
 		}
-		if (strlen(seed) > SKEY_MAX_SEED_LEN) {
-			(void)printf("Notice: Seed truncated to %d characters.\n",
-				     SKEY_MAX_SEED_LEN);
-			seed[SKEY_MAX_SEED_LEN] = '\0';
+
+		/* If new entry is longer than the old, comment out the old. */
+		if (nlen > skey.len) {
+			(void)skeyzero(&skey, pp->pw_name);
+			/* Re-open keys file and seek to the end */
+			if (skeylookup(&skey, pp->pw_name) == -1)
+				err(1, "cannot reopen database");
+			lockeof(&skey, pp->pw_name);
+		} else {
+			/* Compute how much to space-pad the seed */
+			seedlen = strlen(seed) + (skey.len - nlen);
 		}
+	}
 
-		for (i = 0;; i++) {
-			if (i >= 2)
-				exit(1);
+	if ((skey.val = (char *)malloc(16 + 1)) == NULL)
+		err(1, "Can't allocate memory");
+	btoa8(skey.val, key);
 
-			(void)printf("otp-%s %d %s\nS/Key access password: ",
-				     skey_get_algorithm(), n, seed);
-			(void)fgets(buf, sizeof(buf), stdin);
-			rip(buf);
-			backspace(buf);
+	/* Don't save algorithm type for md4 (maintain record length) */
+	/* XXX - should check return values of fprintf + fclose */
+	if (oldmd4)
+		(void)fprintf(skey.keyfile, "%s %04d %-* %s %-21s\n",
+		    pp->pw_name, n, seedlen, seed, skey.val, tbuf);
+	else
+		(void)fprintf(skey.keyfile, "%s %s %04d %-*s %s %-21s\n",
+		    pp->pw_name, skey_get_algorithm(), n, seedlen, seed,
+		    skey.val, tbuf);
+	(void)fclose(skey.keyfile);
 
-			if (buf[0] == '?') {
-				(void)puts("Enter 6 English words from secure S/Key calculation.");
-				continue;
-			} else if (buf[0] == '\0')
-				exit(1);
-			if (etob(key, buf) == 1 || atob8(key, buf) == 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 skeyinit -s.\n", stderr);
+	(void)printf("\nID %s skey is otp-%s %d %s\n", pp->pw_name,
+		     skey_get_algorithm(), n, seed);
+	(void)printf("Next login password: %s\n\n",
+	    hexmode ? put8(buf, key) : btoe(buf, key));
+	exit(0);
+}
 
-		for (i = 0;; i++) {
-			if (i > 2)
-				exit(1);
+void
+lockeof(mp, user)
+	struct skey *mp;
+	char *user;
+{
+	struct flock fl;
 
-			(void)fputs("Enter secret password: ", stderr);
-			readpass(passwd, sizeof(passwd));
-			if (passwd[0] == '\0')
-				exit(1);
+	fseek(mp->keyfile, 0, SEEK_END);
+dolock:
+	fl.l_start = ftell(mp->keyfile);
+	fl.l_len = mp->len;
+	fl.l_pid = getpid();
+	fl.l_type = F_WRLCK;
+	fl.l_whence = SEEK_SET;
 
-			if (strlen(passwd) < SKEY_MIN_PW_LEN) {
-				(void)fprintf(stderr,
-				    "Your password must be at least %d characters long.\n", SKEY_MIN_PW_LEN);
-				continue;
-			} else if (strcmp(passwd, pp->pw_name) == 0) {
-				(void)fputs("Your password may not be the same as your user name.\n", stderr);
-				continue;
-			} else if (strspn(passwd, "abcdefghijklmnopqrstuvwxyz") == strlen(passwd)) {
-				(void)fputs("Your password must contain more than just lower case letters.\nWhitespace, numbers, and puctuation are suggested.\n", stderr);
-				continue;
-			}
+	if (fcntl(fileno(mp->keyfile), F_SETLKW, &fl) == -1)
+		err(1, "Can't lock database");
 
-			(void)fputs("Again secret password: ", stderr);
-			readpass(passwd2, sizeof(passwd));
+	/* Make sure we are still at the end. */
+	fseek(mp->keyfile, 0, SEEK_END);
+	if (fl.l_start == ftell(mp->keyfile))
+		return;		/* still at EOF */
 
-			if (strcmp(passwd, passwd2) == 0)
-				break;
+	fclose(mp->keyfile);
+	if (skeylookup(mp, user) != 1)
+		errx(1, "user %s already added", user);
+	goto dolock;
+}
 
-			(void)fputs("Passwords do not match.\n", stderr);
-		}
+void
+secure_mode(count, key, seed, defaultseed, buf, bufsiz)
+	int *count;
+	char *key;
+	char *seed;
+	char *defaultseed;
+	char *buf;
+	size_t bufsiz;
+{
+	int i, n;
+	char *p;
 
-		/* Crunch seed and password into starting key */
-		(void)strcpy(seed, defaultseed);
-		if (keycrunch(key, seed, passwd) != 0)
-			err(2, "key crunch failed");
+	(void)puts("You need the 6 words generated from the \"skey\" command.");
+	for (i = 0; ; i++) {
+		if (i >= 2)
+			exit(1);
 
-		nn = n;
-		while (nn-- != 0)
-			f(key);
+		(void)printf("Enter sequence count from 1 to %d: ",
+		    SKEY_MAX_SEQ);
+		(void)fgets(buf, bufsiz, stdin);
+		clearerr(stdin);
+		n = atoi(buf);
+		if (n > 0 && n < SKEY_MAX_SEQ)
+			break;	/* Valid range */
+		(void)fprintf(stderr, "ERROR: Count must be between 1 and %d\n",
+			     SKEY_MAX_SEQ);
 	}
-	(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");
+	for (i = 0; ; i++) {
+		if (i >= 2)
+			exit(1);
 
-	/* Zero out old key if necesary (entry would change size) */
-	if (zerokey) {
-		(void)skeyzero(&skey, pp->pw_name);
-		/* Re-open keys file and seek to the end */
-		if (skeylookup(&skey, pp->pw_name) == -1)
-			err(1, "cannot open database");
+		(void)printf("Enter new seed [default %s]: ",
+			     defaultseed);
+		(void)fgets(seed, SKEY_MAX_SEED_LEN+2, stdin); /* XXX */
+		clearerr(stdin);
+		rip(seed);
+		if (strlen(seed) > SKEY_MAX_SEED_LEN) {
+			(void)fprintf(stderr, "ERROR: Seed must be between 1 "
+			    "and %d characters in length\n", SKEY_MAX_SEED_LEN);
+			continue;
+		}
+		if (seed[0] == '\0')
+			(void)strcpy(seed, defaultseed);
+		for (p = seed; *p; p++) {
+			if (isspace(*p)) {
+				(void)fputs("ERROR: Seed must not contain "
+				    "any spaces\n", stderr);
+				break;
+			} else if (isalpha(*p)) {
+				if (isupper(*p))
+					*p = tolower(*p);
+			} else if (!isdigit(*p)) {
+				(void)fputs("ERROR: Seed must be purely "
+				    "alphanumeric\n", stderr);
+				break;
+			}
+		}
+		if (*p == '\0')
+			break;  /* Valid seed */
 	}
 
-	btoa8(skey.val, key);
+	for (i = 0; ; i++) {
+		if (i >= 2)
+			exit(1);
 
-	/*
-	 * Obtain an exclusive lock on the key file so we don't
-	 * clobber someone authenticating themselves at the same time.
-	 */
-	for (i = 0; i < 300; i++) {
-		if ((rval = flock(fileno(skey.keyfile), LOCK_EX|LOCK_NB)) == 0
-		    || errno != EWOULDBLOCK)
+		(void)printf("otp-%s %d %s\nS/Key access password: ",
+			     skey_get_algorithm(), n, seed);
+		(void)fgets(buf, bufsiz, stdin);
+		clearerr(stdin);
+		rip(buf);
+		backspace(buf);
+
+		if (buf[0] == '?') {
+			(void)puts("Enter 6 words from secure S/Key calculation.");
+			continue;
+		} else if (buf[0] == '\0')
+			exit(1);
+
+		if (etob(key, buf) == 1 || atob8(key, buf) == 0)
+			break;	/* Valid format */
+		(void)fputs("ERROR: Invalid format - try again with the 6 words.\n",
+		    stderr);
+	}
+	*count= n;
+}
+
+void
+normal_mode(username, n, key, seed, defaultseed)
+	char *username;
+	int n;
+	char *key;
+	char *seed;
+	char *defaultseed;
+{
+	int i, nn;
+	char passwd[SKEY_MAX_PW_LEN+2], passwd2[SKEY_MAX_PW_LEN+2];
+
+	/* Get user's secret passphrase */
+	for (i = 0; ; i++) {
+		if (i > 2)
+			exit(1);
+
+		if (readpassphrase("Enter secret passphrase: ", passwd,
+		    sizeof(passwd), 0) == NULL || passwd[0] == '\0')
+			exit(1);
+
+		if (strlen(passwd) < SKEY_MIN_PW_LEN) {
+			(void)fprintf(stderr,
+			    "ERROR: Your passphrase must be at least %d "
+			    "characters long.\n", SKEY_MIN_PW_LEN);
+			continue;
+		} else if (strcmp(passwd, username) == 0) {
+			(void)fputs("ERROR: Your passphrase may not be the "
+			    "same as your user name.\n", stderr);
+			continue;
+		} else if (strspn(passwd, "abcdefghijklmnopqrstuvwxyz") == 
+		    strlen(passwd)) {
+			(void)fputs("ERROR: Your passphrase must contain more "
+			    "than just lower case letters.\nWhitespace, "
+			    "numbers, and puctuation are suggested.\n", stderr);
+			continue;
+		} else if (strlen(passwd) > 63) {
+			(void)fprintf(stderr, "WARNING: Your passphrase is "
+			    "longer than the recommended maximum length of 63\n");
+		}
+		/* XXX - should check for passphrase that is really too long */
+
+		if (readpassphrase("Again secret passphrase: ", passwd2,
+		    sizeof(passwd2), 0) && strcmp(passwd, passwd2) == 0)
 			break;
-		usleep(100000);			/* Sleep for 0.1 seconds */
+
+		(void)fputs("Passphrases do not match.\n", stderr);
 	}
-	if (rval == -1)	{			/* Can't get exclusive lock */
-		errno = EAGAIN;
-		err(1, "cannot open database");
-	}
 
-	/* Don't save algorithm type for md4 (keep record length same) */
-	if (strcmp(skey_get_algorithm(), "md4") == 0)
-		(void)fprintf(skey.keyfile, "%s %04d %-16s %s %-21s\n",
-		    pp->pw_name, n, seed, skey.val, tbuf);
-	else
-		(void)fprintf(skey.keyfile, "%s %s %04d %-16s %s %-21s\n",
-		    pp->pw_name, skey_get_algorithm(), n, seed, skey.val, tbuf);
+	/* Crunch seed and passphrase into starting key */
+	(void)strcpy(seed, defaultseed);
+	if (keycrunch(key, seed, passwd) != 0)
+		err(2, "key crunch failed");
 
-	(void)fclose(skey.keyfile);
+	nn = n;
+	while (nn-- != 0)
+		f(key);
+}
 
-	(void)printf("\nID %s skey is otp-%s %d %s\n", pp->pw_name,
-		     skey_get_algorithm(), n, seed);
-	(void)printf("Next login password: %s\n\n",
-		     hexmode ? put8(buf, key) : btoe(buf, key));
-	exit(0);
+#define TIMEOUT_MSG	"Timed out waiting for input.\n"
+void
+timedout(signo)
+	int signo;
+{
+
+	write(STDERR_FILENO, TIMEOUT_MSG, sizeof(TIMEOUT_MSG) - 1);
+	_exit(1);
 }
 
 void