remove built-in support for md5crypt()

Users of MD5-hashed password should arrange for ./configure to link
against libxcrypt or similar. Though it would be better to avoid use
of MD5 password hashing entirely, it's arguably worse than DEScrypt.

feedback and ok dtucker@
This commit is contained in:
Damien Miller 2021-05-06 10:08:30 +10:00
parent c5de1fffa6
commit a5ab488234
8 changed files with 10 additions and 232 deletions

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@ -197,11 +197,6 @@ it if lastlog is installed in a different place.
--with-osfsia, --without-osfsia will enable or disable OSF1's Security
Integration Architecture. The default for OSF1 machines is enable.
--with-md5-passwords will enable the use of MD5 passwords. Enable this
if your operating system uses MD5 passwords and the system crypt() does
not support them directly (see the crypt(3/3c) man page). If enabled, the
resulting binary will support both MD5 and traditional crypt passwords.
--with-utmpx enables utmpx support. utmpx support is automatic for
some platforms.

12
LICENCE
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@ -210,22 +210,14 @@ OpenSSH contains no GPL code.
8) Portable OpenSSH contains the following additional licenses:
a) md5crypt.c, md5crypt.h
* "THE BEER-WARE LICENSE" (Revision 42):
* <phk@login.dknet.dk> wrote this file. As long as you retain this
* notice you can do whatever you want with this stuff. If we meet
* some day, and you think this stuff is worth it, you can buy me a
* beer in return. Poul-Henning Kamp
b) snprintf replacement
a) snprintf replacement
* Copyright Patrick Powell 1995
* This code is based on code written by Patrick Powell
* (papowell@astart.com) It may be used for any purpose as long as this
* notice remains intact on all source code distributions
c) Compatibility code (openbsd-compat)
b) Compatibility code (openbsd-compat)
Apart from the previously mentioned licenses, various pieces of code
in the openbsd-compat/ subdirectory are licensed as follows:

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@ -127,7 +127,7 @@ SSHDOBJS=sshd.o auth-rhosts.o auth-passwd.o \
auth2-none.o auth2-passwd.o auth2-pubkey.o \
monitor.o monitor_wrap.o auth-krb5.o \
auth2-gss.o gss-serv.o gss-serv-krb5.o \
loginrec.o auth-pam.o auth-shadow.o auth-sia.o md5crypt.o \
loginrec.o auth-pam.o auth-shadow.o auth-sia.o \
srclimit.o sftp-server.o sftp-common.o \
sandbox-null.o sandbox-rlimit.o sandbox-systrace.o sandbox-darwin.o \
sandbox-seccomp-filter.o sandbox-capsicum.o sandbox-pledge.o \

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@ -1859,7 +1859,6 @@ AC_CHECK_FUNCS([ \
localtime_r \
login_getcapbool \
login_getpwclass \
md5_crypt \
memmem \
memmove \
memset_s \
@ -4943,19 +4942,6 @@ else
fi
AC_SUBST([mansubdir])
# Check whether to enable MD5 passwords
MD5_MSG="no"
AC_ARG_WITH([md5-passwords],
[ --with-md5-passwords Enable use of MD5 passwords],
[
if test "x$withval" != "xno" ; then
AC_DEFINE([HAVE_MD5_PASSWORDS], [1],
[Define if you want to allow MD5 passwords])
MD5_MSG="yes"
fi
]
)
# Whether to disable shadow password support
AC_ARG_WITH([shadow],
[ --without-shadow Disable shadow password support],
@ -5550,7 +5536,6 @@ echo " PAM support: $PAM_MSG"
echo " OSF SIA support: $SIA_MSG"
echo " KerberosV support: $KRB5_MSG"
echo " SELinux support: $SELINUX_MSG"
echo " MD5 password support: $MD5_MSG"
echo " libedit support: $LIBEDIT_MSG"
echo " libldns support: $LDNS_MSG"
echo " Solaris process contract support: $SPC_MSG"

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@ -66,7 +66,7 @@
# rpm -ba|--rebuild --define "smartcard 1"
%{?smartcard:%global scard 1}
# Is this a build for the rescue CD (without PAM, with MD5)? (1=yes 0=no)
# Is this a build for the rescue CD (without PAM)? (1=yes 0=no)
%global rescue 0
%{?build_rescue:%global rescue 1}
@ -211,7 +211,6 @@ CFLAGS="$RPM_OPT_FLAGS -Os"; export CFLAGS
--with-default-path=/usr/local/bin:/bin:/usr/bin \
--with-superuser-path=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin \
--with-privsep-path=%{_var}/empty/sshd \
--with-md5-passwords \
--mandir=%{_mandir} \
--with-mantype=man \
--disable-strip \
@ -424,7 +423,10 @@ fi
%endif
%changelog
* Mon Jul 20 2020 Damien Miller <djm@mindrto.org>
* Thu Oct 28 2021 Damien Miller <djm@mindrot.org>
- Remove remaining traces of --with-md5-passwords
* Mon Jul 20 2020 Damien Miller <djm@mindrot.org>
- Add ssh-sk-helper and corresponding manual page.
* Sat Feb 10 2018 Darren Tucker <dtucker@dtucker.net>

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@ -1,165 +0,0 @@
/*
* ----------------------------------------------------------------------------
* "THE BEER-WARE LICENSE" (Revision 42):
* <phk@login.dknet.dk> wrote this file. As long as you retain this
* notice you can do whatever you want with this stuff. If we meet some
* day, and you think this stuff is worth it, you can buy me a beer in
* return. Poul-Henning Kamp
* ----------------------------------------------------------------------------
*/
#include "includes.h"
#if defined(HAVE_MD5_PASSWORDS) && !defined(HAVE_MD5_CRYPT)
#include <sys/types.h>
#include <string.h>
#include <openssl/md5.h>
/* 0 ... 63 => ascii - 64 */
static unsigned char itoa64[] =
"./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
static char *magic = "$1$";
static char *
to64(unsigned long v, int n)
{
static char buf[5];
char *s = buf;
if (n > 4)
return (NULL);
memset(buf, '\0', sizeof(buf));
while (--n >= 0) {
*s++ = itoa64[v&0x3f];
v >>= 6;
}
return (buf);
}
int
is_md5_salt(const char *salt)
{
return (strncmp(salt, magic, strlen(magic)) == 0);
}
char *
md5_crypt(const char *pw, const char *salt)
{
static char passwd[120], salt_copy[9];
static const char *sp, *ep;
unsigned char final[16];
int sl, pl, i, j;
MD5_CTX ctx, ctx1;
unsigned long l;
/* Refine the Salt first */
sp = salt;
/* If it starts with the magic string, then skip that */
if(strncmp(sp, magic, strlen(magic)) == 0)
sp += strlen(magic);
/* It stops at the first '$', max 8 chars */
for (ep = sp; *ep != '$'; ep++) {
if (*ep == '\0' || ep >= (sp + 8))
return (NULL);
}
/* get the length of the true salt */
sl = ep - sp;
/* Stash the salt */
memcpy(salt_copy, sp, sl);
salt_copy[sl] = '\0';
MD5_Init(&ctx);
/* The password first, since that is what is most unknown */
MD5_Update(&ctx, pw, strlen(pw));
/* Then our magic string */
MD5_Update(&ctx, magic, strlen(magic));
/* Then the raw salt */
MD5_Update(&ctx, sp, sl);
/* Then just as many characters of the MD5(pw, salt, pw) */
MD5_Init(&ctx1);
MD5_Update(&ctx1, pw, strlen(pw));
MD5_Update(&ctx1, sp, sl);
MD5_Update(&ctx1, pw, strlen(pw));
MD5_Final(final, &ctx1);
for(pl = strlen(pw); pl > 0; pl -= 16)
MD5_Update(&ctx, final, pl > 16 ? 16 : pl);
/* Don't leave anything around in vm they could use. */
memset(final, '\0', sizeof final);
/* Then something really weird... */
for (j = 0, i = strlen(pw); i != 0; i >>= 1)
if (i & 1)
MD5_Update(&ctx, final + j, 1);
else
MD5_Update(&ctx, pw + j, 1);
/* Now make the output string */
snprintf(passwd, sizeof(passwd), "%s%s$", magic, salt_copy);
MD5_Final(final, &ctx);
/*
* and now, just to make sure things don't run too fast
* On a 60 Mhz Pentium this takes 34 msec, so you would
* need 30 seconds to build a 1000 entry dictionary...
*/
for(i = 0; i < 1000; i++) {
MD5_Init(&ctx1);
if (i & 1)
MD5_Update(&ctx1, pw, strlen(pw));
else
MD5_Update(&ctx1, final, 16);
if (i % 3)
MD5_Update(&ctx1, sp, sl);
if (i % 7)
MD5_Update(&ctx1, pw, strlen(pw));
if (i & 1)
MD5_Update(&ctx1, final, 16);
else
MD5_Update(&ctx1, pw, strlen(pw));
MD5_Final(final, &ctx1);
}
l = (final[ 0]<<16) | (final[ 6]<<8) | final[12];
strlcat(passwd, to64(l, 4), sizeof(passwd));
l = (final[ 1]<<16) | (final[ 7]<<8) | final[13];
strlcat(passwd, to64(l, 4), sizeof(passwd));
l = (final[ 2]<<16) | (final[ 8]<<8) | final[14];
strlcat(passwd, to64(l, 4), sizeof(passwd));
l = (final[ 3]<<16) | (final[ 9]<<8) | final[15];
strlcat(passwd, to64(l, 4), sizeof(passwd));
l = (final[ 4]<<16) | (final[10]<<8) | final[ 5];
strlcat(passwd, to64(l, 4), sizeof(passwd));
l = final[11] ;
strlcat(passwd, to64(l, 2), sizeof(passwd));
/* Don't leave anything around in vm they could use. */
memset(final, 0, sizeof(final));
memset(salt_copy, 0, sizeof(salt_copy));
memset(&ctx, 0, sizeof(ctx));
memset(&ctx1, 0, sizeof(ctx1));
(void)to64(0, 4);
return (passwd);
}
#endif /* defined(HAVE_MD5_PASSWORDS) && !defined(HAVE_MD5_CRYPT) */

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@ -1,22 +0,0 @@
/*
* ----------------------------------------------------------------------------
* "THE BEER-WARE LICENSE" (Revision 42):
* <phk@login.dknet.dk> wrote this file. As long as you retain this notice you
* can do whatever you want with this stuff. If we meet some day, and you think
* this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp
* ----------------------------------------------------------------------------
*/
#ifndef _MD5CRYPT_H
#define _MD5CRYPT_H
#include "config.h"
#if defined(HAVE_MD5_PASSWORDS) && !defined(HAVE_MD5_CRYPT)
int is_md5_salt(const char *);
char *md5_crypt(const char *, const char *);
#endif /* defined(HAVE_MD5_PASSWORDS) && !defined(HAVE_MD5_CRYPT) */
#endif /* MD5CRYPT_H */

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@ -54,10 +54,6 @@
# include <pwdadj.h>
# endif
# if defined(HAVE_MD5_PASSWORDS) && !defined(HAVE_MD5_CRYPT)
# include "md5crypt.h"
# endif
# if defined(WITH_OPENSSL) && !defined(HAVE_CRYPT) && defined(HAVE_DES_CRYPT)
# include <openssl/des.h>
# define crypt DES_crypt
@ -108,12 +104,7 @@ xcrypt(const char *password, const char *salt)
if (salt == NULL)
salt = pick_salt();
# ifdef HAVE_MD5_PASSWORDS
if (is_md5_salt(salt))
crypted = md5_crypt(password, salt);
else
crypted = crypt(password, salt);
# elif defined(__hpux) && !defined(HAVE_SECUREWARE)
#if defined(__hpux) && !defined(HAVE_SECUREWARE)
if (iscomsec())
crypted = bigcrypt(password, salt);
else
@ -122,7 +113,7 @@ xcrypt(const char *password, const char *salt)
crypted = bigcrypt(password, salt);
# else
crypted = crypt(password, salt);
# endif
#endif
return crypted;
}