Add working and easy crypt(3)-switching. Yes, we need a whole new API

for crypt(3) by now.  In any case:

Add crypt_set_format(3) + documentation to -lcrypt.
Add login_setcryptfmt(3) + documentation to -lutil.
Support for switching crypt formats in passwd(8).
Support for switching crypt formats in pw(8).

The simple synopsis is:
edit login.conf; add a passwd_format field set to "des" or "md5"; go nuts :)

Reviewed by:	peter

include/unistd.h

@@ -120,6 +120,8 @@ char	*brk __P((const char *));
 int	 chroot __P((const char *));
 size_t	 confstr __P((int, char *, size_t));
 char	*crypt __P((const char *, const char *));
+const char *crypt_get_format __P((void));
+int	 crypt_set_format __P((const char *));
 int	 des_cipher __P((const char *, char *, long, int));
 int	 des_setkey __P((const char *key));
 int	 encrypt __P((char *, int));

lib/libcrypt/Makefile

@@ -17,9 +17,10 @@ SONAME=		${LCRYPTSO}
 
 .PATH:		${.CURDIR}/../libmd
 SRCS=		crypt.c crypt-md5.c misc.c
-STATICSRCS=	md5c.c
+STATICSRCS=	md5c.c sha1c.c
 STATICOBJS=	${STATICSRCS:S/.c/.o/g}
 MAN3=		crypt.3
+MLINKS=		crypt.3 crypt_get_format.3 crypt.3 crypt_set_format.3
 CFLAGS+=	-I${.CURDIR}/../libmd
 CFLAGS+=	-DLIBC_SCCS -Wall
 PRECIOUSLIB=	yes

lib/libcrypt/crypt.3

@@ -43,6 +43,10 @@
 .Fd #include <unistd.h>
 .Ft char *
 .Fn crypt "const char *key" "const char *salt"
+.Ft const char *
+.Fn crypt_get_format "void"
+.Ft int
+.Fn crypt_set_format "const char *string"
 .Sh DESCRIPTION
 The
 .Fn crypt
@@ -59,10 +63,12 @@ Currently these include the
 .Tn Data Encryption Standard (DES) ,
 and
 .Tn MD5 .
-The algorithm used will depend upon the format of the Salt--following
-the Modular Crypt Format (MCF)--and if
+The algorithm used will depend upon the format of the Salt (following
+the Modular Crypt Format (MCF)), if
 .Tn DES
-is installed or not.
+is installed or not, and whether
+.Fn crypt_set_format
+has been called to change the default.
 .Pp
 The first argument to
 .Nm
@@ -177,10 +183,15 @@ Other crypt formats may be easilly added.  An example salt would be:
 .Ss "Traditional" crypt:
 .Pp
 The algorithm used will depend upon whether
+.Fn crypt_set_format
+has been called and whether
 .Tn DES
-is installed or not.  If it is,
+is installed or not.  If
 .Tn DES
-will be used.  Otherwise, the best algorithm is used, which is currently
+is installed and
+.Fn crypt_set_format
+has not set the format to something else, it will be used.
+Otherwise, the best algorithm is used, which is currently
 .\"
 .\" NOTICE: Also make sure to update this
 .\"
@@ -188,6 +199,23 @@ MD5.
 .Pp
 How the salt is used will depend upon the algorithm for the hash.  For
 best results, specify at least two characters of salt.
+.Pp
+The
+.Fn crypt_get_format
+function returns a constant string that represents the name of the
+algorithm currently used.
+Valid values are
+.\"
+.\" NOTICE: Also make sure to update this, too, as well
+.\"
+.Ql des
+and
+.Ql md5 .
+.Pp
+The
+.Fn crypt_set_format
+function sets the default encoding format according to the supplied
+.Fa string .
 .Sh RETURN VALUES
 .Pp
 .Fn crypt
@@ -195,6 +223,10 @@ returns a pointer to the encrypted value on success, and NULL on failure.
 Note: this is not a standard behaviour, AT&T
 .Fn crypt
 will always return a pointer to a string.
+.Pp
+.Fn crypt_set_format
+will return 1 if the supplied encoding format was valid.
+Otherwise, a value of 0 is returned.
 .Sh SEE ALSO
 .Xr login 1 ,
 .Xr passwd 1 ,
@@ -206,7 +238,9 @@ The
 .Fn crypt
 function returns a pointer to static data, and subsequent calls to
 .Fn crypt
-will modify the same data.
+will modify the same data.  Likewise,
+.Fn crypt_set_format
+modifies static data.
 .Sh HISTORY
 A rotor-based
 .Fn crypt
@@ -230,6 +264,7 @@ Originally written by
 .An David Burren Aq davidb@werj.com.au ,
 later additions and changes by
 .An Poul-henning Kamp ,
-.An Mark R V Murray
-and
+.An Mark R V Murray ,
 .An Kris Kennaway .
+and
+.An Brian Feldman .

lib/libcrypt/crypt.c

@@ -34,14 +34,57 @@ static char rcsid[] = "$FreeBSD$";
 #include <string.h>
 #include "crypt.h"
 
+static const struct {
+	const char *const name;
+	char *(*const func)(const char *, const char *);
+	const char *const magic;
+} crypt_types[] = {
+	{
+		"des",
+		crypt_des,
+		NULL
+	},
+	{
+		"md5",
+		crypt_md5,
+		"$1$"
+	},
+	{
+		NULL,
+		NULL
+	}
+};
+
+static int crypt_type = 0;
+
+const char *
+crypt_get_format(void) {
+
+	return (crypt_types[crypt_type].name);
+}
+
+int
+crypt_set_format(char *type) {
+	int i;
+
+	for (i = 0; i < sizeof(crypt_types) / sizeof(crypt_types[0]) - 1; i++) {
+		if (strcmp(type, crypt_types[i].name) == 0) {
+			crypt_type = i;
+			return (1);
+		}
+	}
+	return (0);
+}
+
 char *
 crypt(char *passwd, char *salt)
 {
-	if (!strncmp(salt, "$1$", 3))
-		return crypt_md5(passwd, salt);
-#ifdef NONEXPORTABLE_CRYPT
-	return crypt_des(passwd, salt);
-#else
-	return crypt_md5(passwd, salt);
-#endif
+	int i;
+
+	for (i = 0; i < sizeof(crypt_types) / sizeof(crypt_types[0]) - 1; i++) {
+		if (crypt_types[i].magic != NULL && strncmp(salt,
+		    crypt_types[i].magic, strlen(crypt_types[i].magic)) == 0)
+			return (crypt_types[i].func(passwd, salt));
+	}
+	return (crypt_types[crypt_type].func(passwd, salt));
 }

lib/libcrypt/crypt.h

@@ -29,7 +29,6 @@
 
 /* magic sizes */
 #define MD5_SIZE 16
-#define SHS_SIZE 20
 
 char *crypt_des(const char *pw, const char *salt);
 char *crypt_md5(const char *pw, const char *salt);

lib/libutil/Makefile

@@ -10,6 +10,10 @@ SRCS=	login.c login_tty.c logout.c logwtmp.c pty.c setproctitle.c \
 	login_cap.c login_class.c login_auth.c login_times.c login_ok.c \
 	_secure_path.c uucplock.c property.c auth.c realhostname.c fparseln.c
 INCS=	libutil.h login_cap.h
+
+LDADD+=	-lcrypt
+DPADD+=	${LIBCRYPT}
+
 MAN3+=	login.3 login_auth.3 login_tty.3 logout.3 logwtmp.3 pty.3 \
 	setproctitle.3 login_cap.3 login_class.3 login_times.3 login_ok.3 \
 	_secure_path.3 uucplock.3 property.3 auth.3 realhostname.3 \
@@ -25,7 +29,7 @@ MLINKS+=login_cap.3 login_getclassbyname.3 login_cap.3 login_close.3 \
 	login_cap.3 login_getstyle.3 login_cap.3 login_getcaptime.3 \
 	login_cap.3 login_getcapnum.3 login_cap.3 login_getcapsize.3 \
 	login_cap.3 login_getcapbool.3 login_cap.3 login_getpath.3 \
-	login_cap.3 login_getpwclass.3
+	login_cap.3 login_getpwclass.3 login_cap.3 login_setcryptfmt.3
 MLINKS+=login_class.3 setusercontext.3 login_class.3 setclasscontext.3 \
 	login_class.3 setclassenvironment.3 login_class.3 setclassresources.3
 MLINKS+=login_times.3 parse_lt.3 login_times.3 in_ltm.3 \

lib/libutil/login_cap.3

@@ -34,7 +34,8 @@
 .Nm login_getclassbyname ,
 .Nm login_getpwclass ,
 .Nm login_getstyle ,
-.Nm login_getuserclass
+.Nm login_getuserclass ,
+.Nm login_setcryptfmt
 .Nd functions for accessing the login class capabilities database.
 .Sh LIBRARY
 .Lb libutil
@@ -67,6 +68,8 @@
 .Fn login_getcapbool "login_cap_t *lc" "const char *cap" "int def"
 .Ft char *
 .Fn login_getstyle "login_cap_t *lc" "char *style" "const char *auth"
+.Ft const char *
+.Fn login_setcryptfmt "login_cap_t *lc" "const char *def" "const char *error"
 .Sh DESCRIPTION
 These functions represent a programming interface to the login
 classes database provided in
@@ -396,8 +399,25 @@ the authentication method used for access to the system via the
 network, and standard methods via direct dialup or console
 logins, significantly reducing the risk of password discovery
 by "snooping" network packets.
+.It Fn login_setcryptfmt
+The
+.Fn login_setcryptfmt
+function is used to set the
+.Xr crypt 3
+format using the
+.Ql passwd_format
+configuration entry.
+If no entry is found,
+.Fa def
+is taken to be used as the fallback.
+If calling
+.Xr crypt_set_format 3
+on the specifier fails,
+.Fa error
+is returned to indicate this.
 .El
 .Sh SEE ALSO
+.Xr crypt 3 ,
 .Xr getcap 3 ,
 .Xr login_class 3 ,
 .Xr login.conf 5 ,

lib/libutil/login_cap.c

@@ -798,3 +798,16 @@ login_getstyle(login_cap_t *lc, char *style, const char *auth)
 
     return lc->lc_style;
 }
+
+const char *
+login_setcryptfmt(login_cap_t *lc, const char *def, const char *error)
+{
+	const char *cipher;
+
+	cipher = login_getcapstr(lc, "passwd_format", def, NULL);
+	if (cipher == NULL)
+		return (error);
+	if (!crypt_set_format(cipher))
+		return (error);
+	return (cipher);
+}

lib/libutil/login_cap.h

@@ -110,6 +110,7 @@ rlim_t login_getcapnum __P((login_cap_t *, const char *, rlim_t, rlim_t));
 rlim_t login_getcapsize __P((login_cap_t *, const char *, rlim_t, rlim_t));
 char *login_getpath __P((login_cap_t *, const char *, char *));
 int login_getcapbool __P((login_cap_t *, const char *, int));
+const char *login_setcryptfmt __P((login_cap_t *, const char *, const char *));
 
 int setclasscontext __P((const char*, unsigned int));
 int setusercontext __P((login_cap_t*, const struct passwd*, uid_t, unsigned int));

secure/lib/libcrypt/Makefile

@@ -21,6 +21,7 @@ STATICSRCS=	md5c.c
 STATICOBJS=	${STATICSRCS:S/.c/.o/g}
 SRCS+=		crypt-des.c
 MAN3=		crypt.3
+MLINKS=		crypt.3 crypt_get_format.3 crypt.3 crypt_set_format.3
 CFLAGS+=	-I${.CURDIR}/../../../lib/libmd
 CFLAGS+=	-I${.CURDIR}/../../../lib/libcrypt
 CFLAGS+=	-DNONEXPORTABLE_CRYPT

usr.bin/passwd/local_passwd.c

@@ -172,20 +172,13 @@ getnewpasswd(pw, nis)
 #else
 	/* Make a good size salt for algoritms that can use it. */
 	gettimeofday(&tv,0);
-	if (strncmp(pw->pw_passwd, "$1$", 3)) {
-	    /* DES Salt */
-	    to64(&salt[0], random(), 3);
-	    to64(&salt[3], tv.tv_usec, 3);
-	    to64(&salt[6], tv.tv_sec, 2);
-	    salt[8] = '\0';
-	}
-	else {
-	    /* MD5 Salt */
-	    strncpy(&salt[0], "$1$", 3);
-	    to64(&salt[3], random(), 3);
-	    to64(&salt[6], tv.tv_usec, 3);
-	    salt[8] = '\0';
-	}
+	if (login_setcryptfmt(lc, "md5", NULL) == NULL)
+		pw_error("cannot set password cipher", 1, 1);
+	/* Salt suitable for anything */
+	to64(&salt[0], random(), 3);
+	to64(&salt[3], tv.tv_usec, 3);
+	to64(&salt[6], tv.tv_sec, 2);
+	salt[8] = '\0';
 #endif
 	return (crypt(buf, salt));
 }

usr.sbin/pw/Makefile

@@ -11,8 +11,8 @@ MAN8=	pw.8
 
 #RND=	-DUSE_MD5RAND
 CFLAGS+= -W -Wall $(CDB) $(RND)
-LDADD=	-lcrypt
-DPADD=	${LIBCRYPT}
+LDADD=	-lcrypt -lutil
+DPADD=	${LIBCRYPT} ${LIBUTIL}
 
 BINMODE=0555
 

usr.sbin/pw/pw_user.c

@@ -42,6 +42,7 @@ static const char rcsid[] =
 #include <sys/resource.h>
 #include <unistd.h>
 #include <utmp.h>
+#include <login_cap.h>
 #if defined(USE_MD5RAND)
 #include <md5.h>
 #endif
@@ -544,11 +545,19 @@ pw_user(struct userconf * cnf, int mode, struct cargs * args)
 		}
 
 		if ((arg = getarg(args, 'w')) != NULL && getarg(args, 'h') == NULL) {
+			login_cap_t *lc;
+
+			lc = login_getpwclass(pwd);
+			if (lc == NULL ||
+			    login_setcryptfmt(lc, "md5", NULL) == NULL)
+				warn("setting crypt(3) format");
+			login_close(lc);
 			pwd->pw_passwd = pw_password(cnf, args, pwd->pw_name);
 			edited = 1;
 		}
 
 	} else {
+		login_cap_t *lc;
 
 		/*
 		 * Add code
@@ -565,13 +574,17 @@ pw_user(struct userconf * cnf, int mode, struct cargs * args)
 		pwd = &fakeuser;
 		pwd->pw_name = a_name->val;
 		pwd->pw_class = cnf->default_class ? cnf->default_class : "";
-		pwd->pw_passwd = pw_password(cnf, args, pwd->pw_name);
 		pwd->pw_uid = pw_uidpolicy(cnf, args);
 		pwd->pw_gid = pw_gidpolicy(cnf, args, pwd->pw_name, (gid_t) pwd->pw_uid);
 		pwd->pw_change = pw_pwdpolicy(cnf, args);
 		pwd->pw_expire = pw_exppolicy(cnf, args);
 		pwd->pw_dir = pw_homepolicy(cnf, args, pwd->pw_name);
 		pwd->pw_shell = pw_shellpolicy(cnf, args, NULL);
+		lc = login_getpwclass(pwd);
+		if (lc == NULL || login_setcryptfmt(lc, "md5", NULL) == NULL)
+			warn("setting crypt(3) format");
+		login_close(lc);
+		pwd->pw_passwd = pw_password(cnf, args, pwd->pw_name);
 		edited = 1;
 
 		if (pwd->pw_uid == 0 && strcmp(pwd->pw_name, "root") != 0)
@@ -600,6 +613,7 @@ pw_user(struct userconf * cnf, int mode, struct cargs * args)
 			int             b;
 			int             istty = isatty(fd);
 			struct termios  t;
+			login_cap_t	*lc;
 
 			if (istty) {
 				if (tcgetattr(fd, &t) == -1)
@@ -629,6 +643,11 @@ pw_user(struct userconf * cnf, int mode, struct cargs * args)
 				*p = '\0';
 			if (!*line)
 				errx(EX_DATAERR, "empty password read on file descriptor %d", fd);
+			lc = login_getpwclass(pwd);
+			if (lc == NULL ||
+			    login_setcryptfmt(lc, "md5", NULL) == NULL)
+				warn("setting crypt(3) format");
+			login_close(lc);
 			pwd->pw_passwd = pw_pwcrypt(line);
 			edited = 1;
 		}