openldap/libraries/liblutil/passwd.c
1999-12-08 07:07:18 +00:00

567 lines
12 KiB
C

/* $OpenLDAP$ */
/*
* Copyright 1998-1999 The OpenLDAP Foundation, All Rights Reserved.
* COPYING RESTRICTIONS APPLY, see COPYRIGHT file
*/
/*
* lutil_password(credentials, password)
*
* Returns true if user supplied credentials matches
* the stored password.
*
* Due to the use of the crypt(3) function
* this routine is NOT thread-safe.
*/
#include "portable.h"
#include <stdio.h>
#include <ac/stdlib.h>
#include <ac/string.h>
#include <ac/unistd.h>
#include <ac/crypt.h>
#include <lber.h>
#include "lutil_md5.h"
#include "lutil_sha1.h"
#include "lutil.h"
#ifdef HAVE_SHADOW_H
# include <shadow.h>
#endif
#ifdef HAVE_PWD_H
# include <pwd.h>
#endif
struct pw_scheme;
typedef int (*PASSWD_CHK_FUNC)(
const struct pw_scheme *scheme,
const char *passwd,
const char *cred );
typedef char * (*PASSWD_GEN_FUNC) (
const struct pw_scheme *scheme,
const char *passwd );
struct pw_scheme {
char *name;
size_t namelen;
PASSWD_CHK_FUNC chk_fn;
PASSWD_GEN_FUNC gen_fn;
};
/* password check routines */
static int chk_md5(
const struct pw_scheme *scheme,
const char *passwd,
const char *cred );
static int chk_smd5(
const struct pw_scheme *scheme,
const char *passwd,
const char *cred );
static int chk_ssha1(
const struct pw_scheme *scheme,
const char *passwd,
const char *cred );
static int chk_sha1(
const struct pw_scheme *scheme,
const char *passwd,
const char *cred );
static int chk_crypt(
const struct pw_scheme *scheme,
const char *passwd,
const char *cred );
static int chk_unix(
const struct pw_scheme *scheme,
const char *passwd,
const char *cred );
/* password generation routines */
static char *gen_sha1(
const struct pw_scheme *scheme,
const char *passwd );
static char *gen_ssha1(
const struct pw_scheme *scheme,
const char *passwd );
static char *gen_smd5(
const struct pw_scheme *scheme,
const char *passwd );
static char *gen_md5(
const struct pw_scheme *scheme,
const char *passwd );
static char *gen_crypt(
const struct pw_scheme *scheme,
const char *passwd );
static const struct pw_scheme pw_schemes[] =
{
{ "{SSHA}", sizeof("{SSHA}")-1, chk_ssha1, gen_ssha1 },
{ "{SHA}", sizeof("{SHA}")-1, chk_sha1, gen_sha1 },
{ "{SMD5}", sizeof("{SMD5}")-1, chk_smd5, gen_smd5 },
{ "{MD5}", sizeof("{MD5}")-1, chk_md5, gen_md5 },
#ifdef SLAPD_CRYPT
{ "{CRYPT}", sizeof("{CRYPT}")-1, chk_crypt, gen_crypt },
#endif
# if defined( HAVE_GETSPNAM ) \
|| ( defined( HAVE_GETPWNAM ) && defined( HAVE_PW_PASSWD ) )
{ "{UNIX}", sizeof("{UNIX}")-1, chk_unix, NULL },
#endif
#ifdef SLAPD_CLEARTEXT
/* psuedo scheme */
{ "{CLEARTEXT}", 0, NULL, NULL },
#endif
NULL,
};
static const struct pw_scheme *get_scheme(
const char* scheme )
{
int i;
for( i=0; pw_schemes[i].name != NULL; i++) {
if( pw_schemes[i].namelen == 0 ) continue;
if( strncasecmp(scheme, pw_schemes[i].name,
pw_schemes[i].namelen) == 0 )
{
return &pw_schemes[i];
}
}
return NULL;
}
static int is_allowed_scheme(
const char* scheme,
const char** schemes )
{
int i;
if( schemes == NULL ) return 1;
for( i=0; schemes[i] != NULL; i++ ) {
if( strcasecmp( scheme, schemes[i] ) == 0 ) {
return 1;
}
}
return 0;
}
static const char *passwd_scheme(
const struct pw_scheme *scheme,
const char* passwd,
const char** allowed )
{
if( !is_allowed_scheme( scheme->name, allowed ) ) {
return NULL;
}
if( strncasecmp( passwd, scheme->name, scheme->namelen ) == 0 ) {
return &passwd[scheme->namelen];
}
return NULL;
}
/*
* Return 0 if creds are good.
*/
int
lutil_passwd(
const char *passwd, /* stored passwd */
const char *cred, /* user cred */
const char **schemes )
{
int i;
if (cred == NULL || passwd == NULL) {
return -1;
}
for( i=0; pw_schemes[i].name != NULL; i++ ) {
if( pw_schemes[i].chk_fn ) {
const char *p = passwd_scheme( &pw_schemes[i],
passwd, schemes );
if( p != NULL ) {
return (pw_schemes[i].chk_fn)( &pw_schemes[i], p, cred );
}
}
}
#ifdef SLAPD_CLEARTEXT
if( is_allowed_scheme("{CLEARTEXT}", schemes ) ) {
return strcmp( cred, passwd );
}
#else
return 1;
#endif
}
char * lutil_passwd_generate(
const char * passwd,
const char * method )
{
const struct pw_scheme *sc = get_scheme( method );
if( sc == NULL ) return NULL;
if( ! sc->gen_fn ) return NULL;
return (sc->gen_fn)( sc, passwd );
}
static char * pw_string(
const struct pw_scheme *sc,
const char *passwd)
{
size_t pwlen = strlen( passwd );
char *pw = ber_memalloc( sc->namelen + pwlen + 1 );
if( pw == NULL ) return NULL;
memcpy( pw, sc->name, sc->namelen );
memcpy( &pw[sc->namelen], passwd, pwlen );
pw[sc->namelen + pwlen] = '\0';
return pw;
}
static char * pw_string64(
const struct pw_scheme *sc,
const unsigned char *hash, size_t hashlen,
const unsigned char *salt, size_t saltlen )
{
int rc;
char *string;
size_t b64len;
size_t len = hashlen + saltlen;
char *b64;
if( saltlen ) {
/* need to base64 combined string */
string = ber_memalloc( hashlen + saltlen );
if( string == NULL ) {
return NULL;
}
memcpy( string, hash, len );
memcpy( &string[len], salt, saltlen );
len += saltlen;
} else {
string = (char *) hash;
}
b64len = LUTIL_BASE64_ENCODE_LEN( len ) + 1;
b64 = ber_memalloc( b64len + sc->namelen );
if( b64 == NULL ) {
if( saltlen ) ber_memfree( string );
return NULL;
}
memcpy(b64, sc->name, sc->namelen);
rc = lutil_b64_ntop( string, len, &b64[sc->namelen], b64len );
if( saltlen ) ber_memfree( string );
if( rc < 0 ) {
free( b64 );
return NULL;
}
return b64;
}
/* PASSWORD CHECK ROUTINES */
static int chk_ssha1(
const struct pw_scheme *sc,
const char* passwd,
const char* cred )
{
lutil_SHA1_CTX SHA1context;
unsigned char SHA1digest[LUTIL_SHA1_BYTES];
int pw_len = strlen(passwd);
int rc;
unsigned char *orig_pass = NULL;
/* base64 un-encode password */
orig_pass = (unsigned char *) ber_memalloc( (size_t) (
LUTIL_BASE64_DECODE_LEN(pw_len) + 1) );
if( orig_pass == NULL ) return -1;
if ((rc = lutil_b64_pton(passwd, orig_pass, pw_len)) < 0) {
ber_memfree(orig_pass);
return 1;
}
/* hash credentials with salt */
lutil_SHA1Init(&SHA1context);
lutil_SHA1Update(&SHA1context,
(const unsigned char *) cred, strlen(cred));
lutil_SHA1Update(&SHA1context,
(const unsigned char *) &orig_pass[sizeof(SHA1digest)],
rc - sizeof(SHA1digest));
lutil_SHA1Final(SHA1digest, &SHA1context);
/* compare */
rc = memcmp((char *)orig_pass, (char *)SHA1digest, sizeof(SHA1digest));
ber_memfree(orig_pass);
return rc;
}
static int chk_sha1(
const struct pw_scheme *sc,
const char* passwd,
const char* cred )
{
lutil_SHA1_CTX SHA1context;
unsigned char SHA1digest[LUTIL_SHA1_BYTES];
char base64digest[LUTIL_BASE64_ENCODE_LEN(sizeof(SHA1digest))+1];
lutil_SHA1Init(&SHA1context);
lutil_SHA1Update(&SHA1context,
(const unsigned char *) cred, strlen(cred));
lutil_SHA1Final(SHA1digest, &SHA1context);
if (lutil_b64_ntop(SHA1digest, sizeof(SHA1digest),
base64digest, sizeof(base64digest)) < 0)
{
return 1;
}
return strcmp(passwd, base64digest);
}
static int chk_smd5(
const struct pw_scheme *sc,
const char* passwd,
const char* cred )
{
lutil_MD5_CTX MD5context;
unsigned char MD5digest[LUTIL_MD5_BYTES];
int pw_len = strlen(passwd);
int rc;
unsigned char *orig_pass = NULL;
/* base64 un-encode password */
orig_pass = (unsigned char *) ber_memalloc( (size_t) (
LUTIL_BASE64_DECODE_LEN(pw_len) + 1) );
if( orig_pass == NULL ) return -1;
if ((rc = lutil_b64_pton(passwd, orig_pass, pw_len)) < 0) {
ber_memfree(orig_pass);
return 1;
}
/* hash credentials with salt */
lutil_MD5Init(&MD5context);
lutil_MD5Update(&MD5context,
(const unsigned char *) cred, strlen(cred));
lutil_MD5Update(&MD5context,
(const unsigned char *) &orig_pass[sizeof(MD5digest)],
rc - sizeof(MD5digest));
lutil_MD5Final(MD5digest, &MD5context);
/* compare */
rc = memcmp((char *)orig_pass, (char *)MD5digest, sizeof(MD5digest));
ber_memfree(orig_pass);
return rc;
}
static int chk_md5(
const struct pw_scheme *sc,
const char* passwd,
const char* cred )
{
lutil_MD5_CTX MD5context;
unsigned char MD5digest[LUTIL_MD5_BYTES];
char base64digest[LUTIL_BASE64_ENCODE_LEN(sizeof(MD5digest))+1];
lutil_MD5Init(&MD5context);
lutil_MD5Update(&MD5context,
(const unsigned char *)cred, strlen(cred));
lutil_MD5Final(MD5digest, &MD5context);
if ( lutil_b64_ntop(MD5digest, sizeof(MD5digest),
base64digest, sizeof(base64digest)) < 0 )
{
return 1;
}
return strcmp(passwd, base64digest);
}
#ifdef SLAPD_CRYPT
static int chk_crypt(
const struct pw_scheme *sc,
const char* passwd,
const char* cred )
{
return strcmp(passwd, crypt(cred, passwd));
}
# if defined( HAVE_GETSPNAM ) \
|| ( defined( HAVE_GETPWNAM ) && defined( HAVE_PW_PASSWD ) )
static int chk_unix(
const struct pw_scheme *sc,
const char* cred,
const char* p )
{
# ifdef HAVE_GETSPNAM
struct spwd *spwd = getspnam(p);
if(spwd == NULL) {
return 1; /* not found */
}
return strcmp(spwd->sp_pwdp, crypt(cred, spwd->sp_pwdp));
# else
struct passwd *pwd = getpwnam(p);
if(pwd == NULL) {
return 1; /* not found */
}
return strcmp(pwd->pw_passwd, crypt(cred, pwd->pw_passwd));
# endif
# endif
}
#endif
/* PASSWORD CHECK ROUTINES */
static char *gen_ssha1(
const struct pw_scheme *scheme,
const char *passwd )
{
lutil_SHA1_CTX SHA1context;
unsigned char SHA1digest[LUTIL_SHA1_BYTES];
unsigned char salt[4];
if( lutil_entropy( salt, sizeof(salt)) < 0 ) {
return NULL;
}
lutil_SHA1Init( &SHA1context );
lutil_SHA1Update( &SHA1context,
(const unsigned char *)passwd, strlen(passwd) );
lutil_SHA1Update( &SHA1context,
(const unsigned char *)salt, sizeof(salt) );
lutil_SHA1Final( SHA1digest, &SHA1context );
return pw_string64( scheme,
SHA1digest, sizeof(SHA1digest),
salt, sizeof(salt));
}
static char *gen_sha1(
const struct pw_scheme *scheme,
const char *passwd )
{
lutil_SHA1_CTX SHA1context;
unsigned char SHA1digest[20];
lutil_SHA1Init( &SHA1context );
lutil_SHA1Update( &SHA1context,
(const unsigned char *)passwd, strlen(passwd) );
lutil_SHA1Final( SHA1digest, &SHA1context );
return pw_string64( scheme,
SHA1digest, sizeof(SHA1digest),
NULL, 0);
}
static char *gen_smd5(
const struct pw_scheme *scheme,
const char *passwd )
{
lutil_MD5_CTX MD5context;
unsigned char MD5digest[16];
unsigned char salt[4];
if( lutil_entropy( salt, sizeof(salt)) < 0 ) {
return NULL;
}
lutil_MD5Init( &MD5context );
lutil_MD5Update( &MD5context,
(const unsigned char *) passwd, strlen(passwd) );
lutil_MD5Update( &MD5context,
(const unsigned char *) salt, sizeof(salt) );
lutil_MD5Final( MD5digest, &MD5context );
return pw_string64( scheme,
MD5digest, sizeof(MD5digest),
salt, sizeof(salt) );
}
static char *gen_md5(
const struct pw_scheme *scheme,
const char *passwd )
{
lutil_MD5_CTX MD5context;
unsigned char MD5digest[16];
lutil_MD5Init( &MD5context );
lutil_MD5Update( &MD5context,
(const unsigned char *) passwd, strlen(passwd) );
lutil_MD5Final( MD5digest, &MD5context );
return pw_string64( scheme,
MD5digest, sizeof(MD5digest),
NULL, 0 );
}
#ifdef SLAPD_CRYPT
static char *gen_crypt(
const struct pw_scheme *scheme,
const char *passwd )
{
static const unsigned char crypt64[] =
"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz1234567890./";
char *hash = NULL;
unsigned char salt[2];
if( lutil_entropy( salt, sizeof(salt)) < 0 ) {
return NULL;
}
salt[0] = crypt64[ salt[0] % (sizeof(crypt64)-1) ];
salt[1] = crypt64[ salt[1] % (sizeof(crypt64)-1) ];
hash = crypt( passwd, salt );
if( hash = NULL ) return NULL;
return pw_string( scheme, hash );
}
#endif