openldap/libraries/libldap/tls_o.c

1572 lines
35 KiB
C

/* tls_o.c - Handle tls/ssl using OpenSSL */
/* $OpenLDAP$ */
/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
*
* Copyright 2008-2021 The OpenLDAP Foundation.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted only as authorized by the OpenLDAP
* Public License.
*
* A copy of this license is available in the file LICENSE in the
* top-level directory of the distribution or, alternatively, at
* <http://www.OpenLDAP.org/license.html>.
*/
/* ACKNOWLEDGEMENTS: Rewritten by Howard Chu
*/
#include "portable.h"
#ifdef HAVE_OPENSSL
#include "ldap_config.h"
#include <stdio.h>
#include <ac/stdlib.h>
#include <ac/errno.h>
#include <ac/socket.h>
#include <ac/string.h>
#include <ac/ctype.h>
#include <ac/time.h>
#include <ac/unistd.h>
#include <ac/param.h>
#include <ac/dirent.h>
#include "ldap-int.h"
#include "ldap-tls.h"
#ifdef HAVE_OPENSSL_SSL_H
#include <openssl/ssl.h>
#include <openssl/x509v3.h>
#include <openssl/err.h>
#include <openssl/rand.h>
#include <openssl/safestack.h>
#include <openssl/bn.h>
#include <openssl/rsa.h>
#include <openssl/dh.h>
#endif
#if OPENSSL_VERSION_NUMBER >= 0x10100000
#define ASN1_STRING_data(x) ASN1_STRING_get0_data(x)
#endif
typedef SSL_CTX tlso_ctx;
typedef SSL tlso_session;
static BIO_METHOD * tlso_bio_method = NULL;
static BIO_METHOD * tlso_bio_setup( void );
static int tlso_opt_trace = 1;
static void tlso_report_error( void );
static void tlso_info_cb( const SSL *ssl, int where, int ret );
static int tlso_verify_cb( int ok, X509_STORE_CTX *ctx );
static int tlso_verify_ok( int ok, X509_STORE_CTX *ctx );
static int tlso_seed_PRNG( const char *randfile );
#if OPENSSL_VERSION_NUMBER < 0x10100000
/*
* OpenSSL 1.1 API and later has new locking code
*/
static RSA * tlso_tmp_rsa_cb( SSL *ssl, int is_export, int key_length );
#ifdef LDAP_R_COMPILE
/*
* provide mutexes for the OpenSSL library.
*/
static ldap_pvt_thread_mutex_t tlso_mutexes[CRYPTO_NUM_LOCKS];
static void tlso_locking_cb( int mode, int type, const char *file, int line )
{
if ( mode & CRYPTO_LOCK ) {
ldap_pvt_thread_mutex_lock( &tlso_mutexes[type] );
} else {
ldap_pvt_thread_mutex_unlock( &tlso_mutexes[type] );
}
}
#if OPENSSL_VERSION_NUMBER >= 0x0909000
static void tlso_thread_self( CRYPTO_THREADID *id )
{
CRYPTO_THREADID_set_pointer( id, (void *)ldap_pvt_thread_self() );
}
#define CRYPTO_set_id_callback(foo) CRYPTO_THREADID_set_callback(foo)
#else
static unsigned long tlso_thread_self( void )
{
/* FIXME: CRYPTO_set_id_callback only works when ldap_pvt_thread_t
* is an integral type that fits in an unsigned long
*/
/* force an error if the ldap_pvt_thread_t type is too large */
enum { ok = sizeof( ldap_pvt_thread_t ) <= sizeof( unsigned long ) };
typedef struct { int dummy: ok ? 1 : -1; } Check[ok ? 1 : -1];
return (unsigned long) ldap_pvt_thread_self();
}
#endif
static void tlso_thr_init( void )
{
int i;
for( i=0; i< CRYPTO_NUM_LOCKS ; i++ ) {
ldap_pvt_thread_mutex_init( &tlso_mutexes[i] );
}
CRYPTO_set_locking_callback( tlso_locking_cb );
CRYPTO_set_id_callback( tlso_thread_self );
}
#endif /* LDAP_R_COMPILE */
#else
#ifdef LDAP_R_COMPILE
static void tlso_thr_init( void ) {}
#endif
#endif /* OpenSSL 1.1 */
#if OPENSSL_VERSION_NUMBER < 0x10100000
/*
* OpenSSL 1.1 API and later makes the BIO method concrete types internal.
*/
static BIO_METHOD *
BIO_meth_new( int type, const char *name )
{
BIO_METHOD *method = LDAP_MALLOC( sizeof(BIO_METHOD) );
memset( method, 0, sizeof(BIO_METHOD) );
method->type = type;
method->name = name;
return method;
}
static void
BIO_meth_free( BIO_METHOD *meth )
{
if ( meth == NULL ) {
return;
}
LDAP_FREE( meth );
}
#define BIO_meth_set_write(m, f) (m)->bwrite = (f)
#define BIO_meth_set_read(m, f) (m)->bread = (f)
#define BIO_meth_set_puts(m, f) (m)->bputs = (f)
#define BIO_meth_set_gets(m, f) (m)->bgets = (f)
#define BIO_meth_set_ctrl(m, f) (m)->ctrl = (f)
#define BIO_meth_set_create(m, f) (m)->create = (f)
#define BIO_meth_set_destroy(m, f) (m)->destroy = (f)
#endif /* OpenSSL 1.1 */
static STACK_OF(X509_NAME) *
tlso_ca_list( char * bundle, char * dir, X509 *cert )
{
STACK_OF(X509_NAME) *ca_list = NULL;
if ( bundle ) {
ca_list = SSL_load_client_CA_file( bundle );
}
#if defined(HAVE_DIRENT_H) || defined(dirent)
if ( dir ) {
int freeit = 0;
if ( !ca_list ) {
ca_list = sk_X509_NAME_new_null();
freeit = 1;
}
if ( !SSL_add_dir_cert_subjects_to_stack( ca_list, dir ) &&
freeit ) {
sk_X509_NAME_free( ca_list );
ca_list = NULL;
}
}
#endif
if ( cert ) {
X509_NAME *xn = X509_get_subject_name( cert );
xn = X509_NAME_dup( xn );
if ( !ca_list )
ca_list = sk_X509_NAME_new_null();
if ( xn && ca_list )
sk_X509_NAME_push( ca_list, xn );
}
return ca_list;
}
/*
* Initialize TLS subsystem. Should be called only once.
*/
static int
tlso_init( void )
{
struct ldapoptions *lo = LDAP_INT_GLOBAL_OPT();
#ifdef HAVE_EBCDIC
{
char *file = LDAP_STRDUP( lo->ldo_tls_randfile );
if ( file ) __atoe( file );
(void) tlso_seed_PRNG( file );
LDAP_FREE( file );
}
#else
(void) tlso_seed_PRNG( lo->ldo_tls_randfile );
#endif
#if OPENSSL_VERSION_NUMBER < 0x10100000
SSL_load_error_strings();
SSL_library_init();
OpenSSL_add_all_digests();
#else
OPENSSL_init_ssl(0, NULL);
#endif
/* FIXME: mod_ssl does this */
X509V3_add_standard_extensions();
tlso_bio_method = tlso_bio_setup();
return 0;
}
/*
* Tear down the TLS subsystem. Should only be called once.
*/
static void
tlso_destroy( void )
{
struct ldapoptions *lo = LDAP_INT_GLOBAL_OPT();
BIO_meth_free( tlso_bio_method );
#if OPENSSL_VERSION_NUMBER < 0x10100000
EVP_cleanup();
ERR_remove_thread_state(NULL);
ERR_free_strings();
#endif
if ( lo->ldo_tls_randfile ) {
LDAP_FREE( lo->ldo_tls_randfile );
lo->ldo_tls_randfile = NULL;
}
}
static tls_ctx *
tlso_ctx_new( struct ldapoptions *lo )
{
return (tls_ctx *) SSL_CTX_new( SSLv23_method() );
}
static void
tlso_ctx_ref( tls_ctx *ctx )
{
tlso_ctx *c = (tlso_ctx *)ctx;
#if OPENSSL_VERSION_NUMBER < 0x10100000
#define SSL_CTX_up_ref(ctx) CRYPTO_add( &(ctx->references), 1, CRYPTO_LOCK_SSL_CTX )
#endif
SSL_CTX_up_ref( c );
}
static void
tlso_ctx_free ( tls_ctx *ctx )
{
tlso_ctx *c = (tlso_ctx *)ctx;
SSL_CTX_free( c );
}
/*
* initialize a new TLS context
*/
static int
tlso_ctx_init( struct ldapoptions *lo, struct ldaptls *lt, int is_server )
{
tlso_ctx *ctx = (tlso_ctx *)lo->ldo_tls_ctx;
int i;
if ( is_server ) {
SSL_CTX_set_session_id_context( ctx,
(const unsigned char *) "OpenLDAP", sizeof("OpenLDAP")-1 );
}
#ifdef SSL_OP_NO_TLSv1
#ifdef SSL_OP_NO_TLSv1_1
#ifdef SSL_OP_NO_TLSv1_2
if ( lo->ldo_tls_protocol_min > LDAP_OPT_X_TLS_PROTOCOL_TLS1_2)
SSL_CTX_set_options( ctx, SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3 |
SSL_OP_NO_TLSv1 | SSL_OP_NO_TLSv1_1 |
SSL_OP_NO_TLSv1_2 );
else
#endif
if ( lo->ldo_tls_protocol_min > LDAP_OPT_X_TLS_PROTOCOL_TLS1_1)
SSL_CTX_set_options( ctx, SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3 |
SSL_OP_NO_TLSv1 | SSL_OP_NO_TLSv1_1 );
else
#endif
if ( lo->ldo_tls_protocol_min > LDAP_OPT_X_TLS_PROTOCOL_TLS1_0)
SSL_CTX_set_options( ctx, SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3 |
SSL_OP_NO_TLSv1);
else
#endif
if ( lo->ldo_tls_protocol_min > LDAP_OPT_X_TLS_PROTOCOL_SSL3 )
SSL_CTX_set_options( ctx, SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3 );
else if ( lo->ldo_tls_protocol_min > LDAP_OPT_X_TLS_PROTOCOL_SSL2 )
SSL_CTX_set_options( ctx, SSL_OP_NO_SSLv2 );
if ( lo->ldo_tls_ciphersuite &&
!SSL_CTX_set_cipher_list( ctx, lt->lt_ciphersuite ) )
{
Debug1( LDAP_DEBUG_ANY,
"TLS: could not set cipher list %s.\n",
lo->ldo_tls_ciphersuite );
tlso_report_error();
return -1;
}
if ( lo->ldo_tls_cacertfile == NULL && lo->ldo_tls_cacertdir == NULL &&
lo->ldo_tls_cacert.bv_val == NULL ) {
if ( !SSL_CTX_set_default_verify_paths( ctx ) ) {
Debug0( LDAP_DEBUG_ANY, "TLS: "
"could not use default certificate paths" );
tlso_report_error();
return -1;
}
} else {
X509 *cert = NULL;
if ( lo->ldo_tls_cacert.bv_val ) {
const unsigned char *pp = lo->ldo_tls_cacert.bv_val;
cert = d2i_X509( NULL, &pp, lo->ldo_tls_cacert.bv_len );
X509_STORE *store = SSL_CTX_get_cert_store( ctx );
if ( !X509_STORE_add_cert( store, cert )) {
Debug0( LDAP_DEBUG_ANY, "TLS: "
"could not use CA certificate" );
tlso_report_error();
return -1;
}
}
if (( lt->lt_cacertfile || lt->lt_cacertdir ) && !SSL_CTX_load_verify_locations( ctx,
lt->lt_cacertfile, lt->lt_cacertdir ) )
{
Debug2( LDAP_DEBUG_ANY, "TLS: "
"could not load verify locations (file:`%s',dir:`%s').\n",
lo->ldo_tls_cacertfile ? lo->ldo_tls_cacertfile : "",
lo->ldo_tls_cacertdir ? lo->ldo_tls_cacertdir : "" );
tlso_report_error();
return -1;
}
if ( is_server ) {
STACK_OF(X509_NAME) *calist;
/* List of CA names to send to a client */
calist = tlso_ca_list( lt->lt_cacertfile, lt->lt_cacertdir, cert );
if ( !calist ) {
Debug2( LDAP_DEBUG_ANY, "TLS: "
"could not load client CA list (file:`%s',dir:`%s').\n",
lo->ldo_tls_cacertfile ? lo->ldo_tls_cacertfile : "",
lo->ldo_tls_cacertdir ? lo->ldo_tls_cacertdir : "" );
tlso_report_error();
return -1;
}
SSL_CTX_set_client_CA_list( ctx, calist );
}
if ( cert )
X509_free( cert );
}
if ( lo->ldo_tls_cert.bv_val )
{
const unsigned char *pp = lo->ldo_tls_cert.bv_val;
X509 *cert = d2i_X509( NULL, &pp, lo->ldo_tls_cert.bv_len );
if ( !SSL_CTX_use_certificate( ctx, cert )) {
Debug0( LDAP_DEBUG_ANY,
"TLS: could not use certificate.\n" );
tlso_report_error();
return -1;
}
X509_free( cert );
} else
if ( lo->ldo_tls_certfile &&
!SSL_CTX_use_certificate_file( ctx,
lt->lt_certfile, SSL_FILETYPE_PEM ) )
{
Debug1( LDAP_DEBUG_ANY,
"TLS: could not use certificate file `%s'.\n",
lo->ldo_tls_certfile );
tlso_report_error();
return -1;
}
/* Key validity is checked automatically if cert has already been set */
if ( lo->ldo_tls_key.bv_val )
{
const unsigned char *pp = lo->ldo_tls_key.bv_val;
EVP_PKEY *pkey = d2i_AutoPrivateKey( NULL, &pp, lo->ldo_tls_key.bv_len );
if ( !SSL_CTX_use_PrivateKey( ctx, pkey ))
{
Debug0( LDAP_DEBUG_ANY,
"TLS: could not use private key.\n" );
tlso_report_error();
return -1;
}
EVP_PKEY_free( pkey );
} else
if ( lo->ldo_tls_keyfile &&
!SSL_CTX_use_PrivateKey_file( ctx,
lt->lt_keyfile, SSL_FILETYPE_PEM ) )
{
Debug1( LDAP_DEBUG_ANY,
"TLS: could not use key file `%s'.\n",
lo->ldo_tls_keyfile );
tlso_report_error();
return -1;
}
if ( is_server && lo->ldo_tls_dhfile ) {
DH *dh;
BIO *bio;
if (( bio=BIO_new_file( lt->lt_dhfile,"r" )) == NULL ) {
Debug1( LDAP_DEBUG_ANY,
"TLS: could not use DH parameters file `%s'.\n",
lo->ldo_tls_dhfile );
tlso_report_error();
return -1;
}
if (!( dh=PEM_read_bio_DHparams( bio, NULL, NULL, NULL ))) {
Debug1( LDAP_DEBUG_ANY,
"TLS: could not read DH parameters file `%s'.\n",
lo->ldo_tls_dhfile );
tlso_report_error();
BIO_free( bio );
return -1;
}
BIO_free( bio );
SSL_CTX_set_tmp_dh( ctx, dh );
SSL_CTX_set_options( ctx, SSL_OP_SINGLE_DH_USE );
DH_free( dh );
}
if ( lo->ldo_tls_ecname ) {
#ifdef OPENSSL_NO_EC
Debug0( LDAP_DEBUG_ANY,
"TLS: Elliptic Curves not supported.\n" );
return -1;
#else
if ( !SSL_CTX_set1_curves_list( ctx, lt->lt_ecname )) {
Debug1( LDAP_DEBUG_ANY,
"TLS: could not set EC name `%s'.\n",
lo->ldo_tls_ecname );
tlso_report_error();
return -1;
}
/*
* This is a NOP in OpenSSL 1.1.0 and later, where curves are always
* auto-negotiated.
*/
#if OPENSSL_VERSION_NUMBER < 0x10100000UL
if ( SSL_CTX_set_ecdh_auto( ctx, 1 ) <= 0 ) {
Debug0( LDAP_DEBUG_ANY,
"TLS: could not enable automatic EC negotiation.\n" );
}
#endif
#endif /* OPENSSL_NO_EC */
}
if ( tlso_opt_trace ) {
SSL_CTX_set_info_callback( ctx, tlso_info_cb );
}
i = SSL_VERIFY_NONE;
if ( lo->ldo_tls_require_cert ) {
i = SSL_VERIFY_PEER;
if ( lo->ldo_tls_require_cert == LDAP_OPT_X_TLS_DEMAND ||
lo->ldo_tls_require_cert == LDAP_OPT_X_TLS_HARD ) {
i |= SSL_VERIFY_FAIL_IF_NO_PEER_CERT;
}
}
SSL_CTX_set_verify( ctx, i,
lo->ldo_tls_require_cert == LDAP_OPT_X_TLS_ALLOW ?
tlso_verify_ok : tlso_verify_cb );
#if OPENSSL_VERSION_NUMBER < 0x10100000
SSL_CTX_set_tmp_rsa_callback( ctx, tlso_tmp_rsa_cb );
#endif
if ( lo->ldo_tls_crlcheck ) {
X509_STORE *x509_s = SSL_CTX_get_cert_store( ctx );
if ( lo->ldo_tls_crlcheck == LDAP_OPT_X_TLS_CRL_PEER ) {
X509_STORE_set_flags( x509_s, X509_V_FLAG_CRL_CHECK );
} else if ( lo->ldo_tls_crlcheck == LDAP_OPT_X_TLS_CRL_ALL ) {
X509_STORE_set_flags( x509_s,
X509_V_FLAG_CRL_CHECK | X509_V_FLAG_CRL_CHECK_ALL );
}
}
/* Explicitly honor the server side cipher suite preference */
SSL_CTX_set_options( ctx, SSL_OP_CIPHER_SERVER_PREFERENCE );
return 0;
}
static tls_session *
tlso_session_new( tls_ctx *ctx, int is_server )
{
tlso_ctx *c = (tlso_ctx *)ctx;
return (tls_session *)SSL_new( c );
}
static int
tlso_session_connect( LDAP *ld, tls_session *sess, const char *name_in )
{
tlso_session *s = (tlso_session *)sess;
int rc;
#ifdef SSL_CTRL_SET_TLSEXT_HOSTNAME
if ( name_in ) {
rc = SSL_set_tlsext_host_name( s, name_in );
if ( !rc ) /* can fail to strdup the name */
return -1;
}
#endif
/* Caller expects 0 = success, OpenSSL returns 1 = success */
rc = SSL_connect( s ) - 1;
return rc;
}
static int
tlso_session_accept( tls_session *sess )
{
tlso_session *s = (tlso_session *)sess;
/* Caller expects 0 = success, OpenSSL returns 1 = success */
return SSL_accept( s ) - 1;
}
static int
tlso_session_upflags( Sockbuf *sb, tls_session *sess, int rc )
{
tlso_session *s = (tlso_session *)sess;
/* 1 was subtracted above, offset it back now */
rc = SSL_get_error(s, rc+1);
if (rc == SSL_ERROR_WANT_READ) {
sb->sb_trans_needs_read = 1;
return 1;
} else if (rc == SSL_ERROR_WANT_WRITE) {
sb->sb_trans_needs_write = 1;
return 1;
} else if (rc == SSL_ERROR_WANT_CONNECT) {
return 1;
}
return 0;
}
static char *
tlso_session_errmsg( tls_session *sess, int rc, char *buf, size_t len )
{
char err[256] = "";
const char *certerr=NULL;
tlso_session *s = (tlso_session *)sess;
rc = ERR_peek_error();
if ( rc ) {
ERR_error_string_n( rc, err, sizeof(err) );
if ( ( ERR_GET_LIB(rc) == ERR_LIB_SSL ) &&
( ERR_GET_REASON(rc) == SSL_R_CERTIFICATE_VERIFY_FAILED ) ) {
int certrc = SSL_get_verify_result(s);
certerr = (char *)X509_verify_cert_error_string(certrc);
}
snprintf(buf, len, "%s%s%s%s", err, certerr ? " (" :"",
certerr ? certerr : "", certerr ? ")" : "" );
return buf;
}
return NULL;
}
static int
tlso_session_my_dn( tls_session *sess, struct berval *der_dn )
{
tlso_session *s = (tlso_session *)sess;
X509 *x;
X509_NAME *xn;
x = SSL_get_certificate( s );
if (!x) return LDAP_INVALID_CREDENTIALS;
xn = X509_get_subject_name(x);
#if OPENSSL_VERSION_NUMBER < 0x10100000
der_dn->bv_len = i2d_X509_NAME( xn, NULL );
der_dn->bv_val = xn->bytes->data;
#else
{
size_t len = 0;
der_dn->bv_val = NULL;
X509_NAME_get0_der( xn, (const unsigned char **)&der_dn->bv_val, &len );
der_dn->bv_len = len;
}
#endif
/* Don't X509_free, the session is still using it */
return 0;
}
static X509 *
tlso_get_cert( SSL *s )
{
/* If peer cert was bad, treat as if no cert was given */
if (SSL_get_verify_result(s)) {
return NULL;
}
return SSL_get_peer_certificate(s);
}
static int
tlso_session_peer_dn( tls_session *sess, struct berval *der_dn )
{
tlso_session *s = (tlso_session *)sess;
X509 *x = tlso_get_cert( s );
X509_NAME *xn;
if ( !x )
return LDAP_INVALID_CREDENTIALS;
xn = X509_get_subject_name(x);
#if OPENSSL_VERSION_NUMBER < 0x10100000
der_dn->bv_len = i2d_X509_NAME( xn, NULL );
der_dn->bv_val = xn->bytes->data;
#else
{
size_t len = 0;
der_dn->bv_val = NULL;
X509_NAME_get0_der( xn, (const unsigned char **)&der_dn->bv_val, &len );
der_dn->bv_len = len;
}
#endif
X509_free(x);
return 0;
}
/* what kind of hostname were we given? */
#define IS_DNS 0
#define IS_IP4 1
#define IS_IP6 2
static int
tlso_session_chkhost( LDAP *ld, tls_session *sess, const char *name_in )
{
tlso_session *s = (tlso_session *)sess;
int i, ret = LDAP_LOCAL_ERROR;
int chkSAN = ld->ld_options.ldo_tls_require_san, gotSAN = 0;
X509 *x;
const char *name;
char *ptr;
int ntype = IS_DNS, nlen;
#ifdef LDAP_PF_INET6
struct in6_addr addr;
#else
struct in_addr addr;
#endif
if( ldap_int_hostname &&
( !name_in || !strcasecmp( name_in, "localhost" ) ) )
{
name = ldap_int_hostname;
} else {
name = name_in;
}
nlen = strlen(name);
x = tlso_get_cert(s);
if (!x) {
Debug0( LDAP_DEBUG_ANY,
"TLS: unable to get peer certificate.\n" );
/* If this was a fatal condition, things would have
* aborted long before now.
*/
return LDAP_SUCCESS;
}
#ifdef LDAP_PF_INET6
if (inet_pton(AF_INET6, name, &addr)) {
ntype = IS_IP6;
} else
#endif
if ((ptr = strrchr(name, '.')) && isdigit((unsigned char)ptr[1])) {
if (inet_aton(name, (struct in_addr *)&addr)) ntype = IS_IP4;
}
if (chkSAN) {
i = X509_get_ext_by_NID(x, NID_subject_alt_name, -1);
if (i >= 0) {
X509_EXTENSION *ex;
STACK_OF(GENERAL_NAME) *alt;
ex = X509_get_ext(x, i);
alt = X509V3_EXT_d2i(ex);
if (alt) {
int n, len2 = 0;
char *domain = NULL;
GENERAL_NAME *gn;
gotSAN = 1;
if (ntype == IS_DNS) {
domain = strchr(name, '.');
if (domain) {
len2 = nlen - (domain-name);
}
}
n = sk_GENERAL_NAME_num(alt);
for (i=0; i<n; i++) {
char *sn;
int sl;
gn = sk_GENERAL_NAME_value(alt, i);
if (gn->type == GEN_DNS) {
if (ntype != IS_DNS) continue;
sn = (char *) ASN1_STRING_data(gn->d.ia5);
sl = ASN1_STRING_length(gn->d.ia5);
/* ignore empty */
if (sl == 0) continue;
/* Is this an exact match? */
if ((nlen == sl) && !strncasecmp(name, sn, nlen)) {
break;
}
/* Is this a wildcard match? */
if (domain && (sn[0] == '*') && (sn[1] == '.') &&
(len2 == sl-1) && !strncasecmp(domain, &sn[1], len2))
{
break;
}
} else if (gn->type == GEN_IPADD) {
if (ntype == IS_DNS) continue;
sn = (char *) ASN1_STRING_data(gn->d.ia5);
sl = ASN1_STRING_length(gn->d.ia5);
#ifdef LDAP_PF_INET6
if (ntype == IS_IP6 && sl != sizeof(struct in6_addr)) {
continue;
} else
#endif
if (ntype == IS_IP4 && sl != sizeof(struct in_addr)) {
continue;
}
if (!memcmp(sn, &addr, sl)) {
break;
}
}
}
GENERAL_NAMES_free(alt);
if (i < n) { /* Found a match */
ret = LDAP_SUCCESS;
}
}
}
}
if (ret != LDAP_SUCCESS && chkSAN) {
switch(chkSAN) {
case LDAP_OPT_X_TLS_DEMAND:
case LDAP_OPT_X_TLS_HARD:
if (!gotSAN) {
Debug0( LDAP_DEBUG_ANY,
"TLS: unable to get subjectAltName from peer certificate.\n" );
ret = LDAP_CONNECT_ERROR;
if ( ld->ld_error ) {
LDAP_FREE( ld->ld_error );
}
ld->ld_error = LDAP_STRDUP(
_("TLS: unable to get subjectAltName from peer certificate"));
goto done;
}
/* FALLTHRU */
case LDAP_OPT_X_TLS_TRY:
if (gotSAN) {
Debug1( LDAP_DEBUG_ANY, "TLS: hostname (%s) does not match "
"subjectAltName in certificate.\n",
name );
ret = LDAP_CONNECT_ERROR;
if ( ld->ld_error ) {
LDAP_FREE( ld->ld_error );
}
ld->ld_error = LDAP_STRDUP(
_("TLS: hostname does not match subjectAltName in peer certificate"));
goto done;
}
break;
case LDAP_OPT_X_TLS_ALLOW:
break;
}
}
if (ret != LDAP_SUCCESS) {
X509_NAME *xn;
X509_NAME_ENTRY *ne;
ASN1_OBJECT *obj;
ASN1_STRING *cn = NULL;
int navas;
/* find the last CN */
obj = OBJ_nid2obj( NID_commonName );
if ( !obj ) goto no_cn; /* should never happen */
xn = X509_get_subject_name(x);
navas = X509_NAME_entry_count( xn );
for ( i=navas-1; i>=0; i-- ) {
ne = X509_NAME_get_entry( xn, i );
if ( !OBJ_cmp( X509_NAME_ENTRY_get_object(ne), obj )) {
cn = X509_NAME_ENTRY_get_data( ne );
break;
}
}
if( !cn )
{
no_cn:
Debug0( LDAP_DEBUG_ANY,
"TLS: unable to get common name from peer certificate.\n" );
ret = LDAP_CONNECT_ERROR;
if ( ld->ld_error ) {
LDAP_FREE( ld->ld_error );
}
ld->ld_error = LDAP_STRDUP(
_("TLS: unable to get CN from peer certificate"));
} else if ( cn->length == nlen &&
strncasecmp( name, (char *) cn->data, nlen ) == 0 ) {
ret = LDAP_SUCCESS;
} else if (( cn->data[0] == '*' ) && ( cn->data[1] == '.' )) {
char *domain = strchr(name, '.');
if( domain ) {
int dlen;
dlen = nlen - (domain-name);
/* Is this a wildcard match? */
if ((dlen == cn->length-1) &&
!strncasecmp(domain, (char *) &cn->data[1], dlen)) {
ret = LDAP_SUCCESS;
}
}
}
if( ret == LDAP_LOCAL_ERROR ) {
Debug3( LDAP_DEBUG_ANY, "TLS: hostname (%s) does not match "
"common name in certificate (%.*s).\n",
name, cn->length, cn->data );
ret = LDAP_CONNECT_ERROR;
if ( ld->ld_error ) {
LDAP_FREE( ld->ld_error );
}
ld->ld_error = LDAP_STRDUP(
_("TLS: hostname does not match name in peer certificate"));
}
}
done:
X509_free(x);
return ret;
}
static int
tlso_session_strength( tls_session *sess )
{
tlso_session *s = (tlso_session *)sess;
return SSL_CIPHER_get_bits(SSL_get_current_cipher(s), NULL);
}
static int
tlso_session_unique( tls_session *sess, struct berval *buf, int is_server)
{
tlso_session *s = (tlso_session *)sess;
/* Usually the client sends the finished msg. But if the
* session was resumed, the server sent the msg.
*/
if (SSL_session_reused(s) ^ !is_server)
buf->bv_len = SSL_get_finished(s, buf->bv_val, buf->bv_len);
else
buf->bv_len = SSL_get_peer_finished(s, buf->bv_val, buf->bv_len);
return buf->bv_len;
}
static int
tlso_session_endpoint( tls_session *sess, struct berval *buf, int is_server )
{
tlso_session *s = (tlso_session *)sess;
const EVP_MD *md;
unsigned int md_len;
X509 *cert;
if ( buf->bv_len < EVP_MAX_MD_SIZE )
return 0;
if ( is_server )
cert = SSL_get_certificate( s );
else
cert = SSL_get_peer_certificate( s );
if ( cert == NULL )
return 0;
#if OPENSSL_VERSION_NUMBER >= 0x10100000
md = EVP_get_digestbynid( X509_get_signature_nid( cert ));
#else
md = EVP_get_digestbynid(OBJ_obj2nid( cert->sig_alg->algorithm ));
#endif
/* See RFC 5929 */
if ( md == NULL ||
md == EVP_md_null() ||
#ifndef OPENSSL_NO_MD2
md == EVP_md2() ||
#endif
md == EVP_md4() ||
md == EVP_md5() ||
md == EVP_sha1() )
md = EVP_sha256();
if ( !X509_digest( cert, md, buf->bv_val, &md_len ))
return 0;
buf->bv_len = md_len;
return md_len;
}
static const char *
tlso_session_version( tls_session *sess )
{
tlso_session *s = (tlso_session *)sess;
return SSL_get_version(s);
}
static const char *
tlso_session_cipher( tls_session *sess )
{
tlso_session *s = (tlso_session *)sess;
return SSL_CIPHER_get_name(SSL_get_current_cipher(s));
}
static int
tlso_session_peercert( tls_session *sess, struct berval *der )
{
tlso_session *s = (tlso_session *)sess;
unsigned char *ptr;
X509 *x = SSL_get_peer_certificate(s);
der->bv_len = i2d_X509(x, NULL);
der->bv_val = LDAP_MALLOC(der->bv_len);
if ( !der->bv_val )
return -1;
ptr = der->bv_val;
i2d_X509(x, &ptr);
return 0;
}
static int
tlso_session_pinning( LDAP *ld, tls_session *sess, char *hashalg, struct berval *hash )
{
tlso_session *s = (tlso_session *)sess;
unsigned char *tmp, digest[EVP_MAX_MD_SIZE];
struct berval key,
keyhash = { sizeof(digest), digest };
X509 *cert = SSL_get_peer_certificate(s);
int len, rc = LDAP_SUCCESS;
len = i2d_X509_PUBKEY( X509_get_X509_PUBKEY(cert), NULL );
key.bv_val = tmp = LDAP_MALLOC( len );
if ( !key.bv_val ) {
return -1;
}
key.bv_len = i2d_X509_PUBKEY( X509_get_X509_PUBKEY(cert), &tmp );
if ( hashalg ) {
const EVP_MD *md;
EVP_MD_CTX *mdctx;
unsigned int len = keyhash.bv_len;
md = EVP_get_digestbyname( hashalg );
if ( !md ) {
Debug1( LDAP_DEBUG_TRACE, "tlso_session_pinning: "
"hash %s not recognised by OpenSSL\n", hashalg );
rc = -1;
goto done;
}
#if OPENSSL_VERSION_NUMBER >= 0x10100000
mdctx = EVP_MD_CTX_new();
#else
mdctx = EVP_MD_CTX_create();
#endif
if ( !mdctx ) {
rc = -1;
goto done;
}
EVP_DigestInit_ex( mdctx, md, NULL );
EVP_DigestUpdate( mdctx, key.bv_val, key.bv_len );
EVP_DigestFinal_ex( mdctx, (unsigned char *)keyhash.bv_val, &len );
keyhash.bv_len = len;
#if OPENSSL_VERSION_NUMBER >= 0x10100000
EVP_MD_CTX_free( mdctx );
#else
EVP_MD_CTX_destroy( mdctx );
#endif
} else {
keyhash = key;
}
if ( ber_bvcmp( hash, &keyhash ) ) {
rc = LDAP_CONNECT_ERROR;
Debug0( LDAP_DEBUG_ANY, "tlso_session_pinning: "
"public key hash does not match provided pin.\n" );
if ( ld->ld_error ) {
LDAP_FREE( ld->ld_error );
}
ld->ld_error = LDAP_STRDUP(
_("TLS: public key hash does not match provided pin"));
}
done:
LDAP_FREE( key.bv_val );
return rc;
}
/*
* TLS support for LBER Sockbufs
*/
struct tls_data {
tlso_session *session;
Sockbuf_IO_Desc *sbiod;
};
#if OPENSSL_VERSION_NUMBER < 0x10100000
#define BIO_set_init(b, x) b->init = x
#define BIO_set_data(b, x) b->ptr = x
#define BIO_clear_flags(b, x) b->flags &= ~(x)
#define BIO_get_data(b) b->ptr
#endif
static int
tlso_bio_create( BIO *b ) {
BIO_set_init( b, 1 );
BIO_set_data( b, NULL );
BIO_clear_flags( b, ~0 );
return 1;
}
static int
tlso_bio_destroy( BIO *b )
{
if ( b == NULL ) return 0;
BIO_set_data( b, NULL ); /* sb_tls_remove() will free it */
BIO_set_init( b, 0 );
BIO_clear_flags( b, ~0 );
return 1;
}
static int
tlso_bio_read( BIO *b, char *buf, int len )
{
struct tls_data *p;
int ret;
if ( buf == NULL || len <= 0 ) return 0;
p = (struct tls_data *)BIO_get_data(b);
if ( p == NULL || p->sbiod == NULL ) {
return 0;
}
ret = LBER_SBIOD_READ_NEXT( p->sbiod, buf, len );
BIO_clear_retry_flags( b );
if ( ret < 0 ) {
int err = sock_errno();
if ( err == EAGAIN || err == EWOULDBLOCK ) {
BIO_set_retry_read( b );
}
}
return ret;
}
static int
tlso_bio_write( BIO *b, const char *buf, int len )
{
struct tls_data *p;
int ret;
if ( buf == NULL || len <= 0 ) return 0;
p = (struct tls_data *)BIO_get_data(b);
if ( p == NULL || p->sbiod == NULL ) {
return 0;
}
ret = LBER_SBIOD_WRITE_NEXT( p->sbiod, (char *)buf, len );
BIO_clear_retry_flags( b );
if ( ret < 0 ) {
int err = sock_errno();
if ( err == EAGAIN || err == EWOULDBLOCK ) {
BIO_set_retry_write( b );
}
}
return ret;
}
static long
tlso_bio_ctrl( BIO *b, int cmd, long num, void *ptr )
{
if ( cmd == BIO_CTRL_FLUSH ) {
/* The OpenSSL library needs this */
return 1;
}
return 0;
}
static int
tlso_bio_gets( BIO *b, char *buf, int len )
{
return -1;
}
static int
tlso_bio_puts( BIO *b, const char *str )
{
return tlso_bio_write( b, str, strlen( str ) );
}
static BIO_METHOD *
tlso_bio_setup( void )
{
/* it's a source/sink BIO */
BIO_METHOD * method = BIO_meth_new( 100 | 0x400, "sockbuf glue" );
BIO_meth_set_write( method, tlso_bio_write );
BIO_meth_set_read( method, tlso_bio_read );
BIO_meth_set_puts( method, tlso_bio_puts );
BIO_meth_set_gets( method, tlso_bio_gets );
BIO_meth_set_ctrl( method, tlso_bio_ctrl );
BIO_meth_set_create( method, tlso_bio_create );
BIO_meth_set_destroy( method, tlso_bio_destroy );
return method;
}
static int
tlso_sb_setup( Sockbuf_IO_Desc *sbiod, void *arg )
{
struct tls_data *p;
BIO *bio;
assert( sbiod != NULL );
p = LBER_MALLOC( sizeof( *p ) );
if ( p == NULL ) {
return -1;
}
p->session = arg;
p->sbiod = sbiod;
bio = BIO_new( tlso_bio_method );
BIO_set_data( bio, p );
SSL_set_bio( p->session, bio, bio );
sbiod->sbiod_pvt = p;
return 0;
}
static int
tlso_sb_remove( Sockbuf_IO_Desc *sbiod )
{
struct tls_data *p;
assert( sbiod != NULL );
assert( sbiod->sbiod_pvt != NULL );
p = (struct tls_data *)sbiod->sbiod_pvt;
SSL_free( p->session );
LBER_FREE( sbiod->sbiod_pvt );
sbiod->sbiod_pvt = NULL;
return 0;
}
static int
tlso_sb_close( Sockbuf_IO_Desc *sbiod )
{
struct tls_data *p;
assert( sbiod != NULL );
assert( sbiod->sbiod_pvt != NULL );
p = (struct tls_data *)sbiod->sbiod_pvt;
SSL_shutdown( p->session );
return 0;
}
static int
tlso_sb_ctrl( Sockbuf_IO_Desc *sbiod, int opt, void *arg )
{
struct tls_data *p;
assert( sbiod != NULL );
assert( sbiod->sbiod_pvt != NULL );
p = (struct tls_data *)sbiod->sbiod_pvt;
if ( opt == LBER_SB_OPT_GET_SSL ) {
*((tlso_session **)arg) = p->session;
return 1;
} else if ( opt == LBER_SB_OPT_DATA_READY ) {
if( SSL_pending( p->session ) > 0 ) {
return 1;
}
}
return LBER_SBIOD_CTRL_NEXT( sbiod, opt, arg );
}
static ber_slen_t
tlso_sb_read( Sockbuf_IO_Desc *sbiod, void *buf, ber_len_t len)
{
struct tls_data *p;
ber_slen_t ret;
int err;
assert( sbiod != NULL );
assert( SOCKBUF_VALID( sbiod->sbiod_sb ) );
p = (struct tls_data *)sbiod->sbiod_pvt;
ret = SSL_read( p->session, (char *)buf, len );
#ifdef HAVE_WINSOCK
errno = WSAGetLastError();
#endif
err = SSL_get_error( p->session, ret );
if (err == SSL_ERROR_WANT_READ ) {
sbiod->sbiod_sb->sb_trans_needs_read = 1;
sock_errset(EWOULDBLOCK);
}
else
sbiod->sbiod_sb->sb_trans_needs_read = 0;
return ret;
}
static ber_slen_t
tlso_sb_write( Sockbuf_IO_Desc *sbiod, void *buf, ber_len_t len)
{
struct tls_data *p;
ber_slen_t ret;
int err;
assert( sbiod != NULL );
assert( SOCKBUF_VALID( sbiod->sbiod_sb ) );
p = (struct tls_data *)sbiod->sbiod_pvt;
ret = SSL_write( p->session, (char *)buf, len );
#ifdef HAVE_WINSOCK
errno = WSAGetLastError();
#endif
err = SSL_get_error( p->session, ret );
if (err == SSL_ERROR_WANT_WRITE ) {
sbiod->sbiod_sb->sb_trans_needs_write = 1;
sock_errset(EWOULDBLOCK);
} else {
sbiod->sbiod_sb->sb_trans_needs_write = 0;
}
return ret;
}
static Sockbuf_IO tlso_sbio =
{
tlso_sb_setup, /* sbi_setup */
tlso_sb_remove, /* sbi_remove */
tlso_sb_ctrl, /* sbi_ctrl */
tlso_sb_read, /* sbi_read */
tlso_sb_write, /* sbi_write */
tlso_sb_close /* sbi_close */
};
/* Derived from openssl/apps/s_cb.c */
static void
tlso_info_cb( const SSL *ssl, int where, int ret )
{
int w;
char *op;
char *state = (char *) SSL_state_string_long( (SSL *)ssl );
w = where & ~SSL_ST_MASK;
if ( w & SSL_ST_CONNECT ) {
op = "SSL_connect";
} else if ( w & SSL_ST_ACCEPT ) {
op = "SSL_accept";
} else {
op = "undefined";
}
#ifdef HAVE_EBCDIC
if ( state ) {
state = LDAP_STRDUP( state );
__etoa( state );
}
#endif
if ( where & SSL_CB_LOOP ) {
Debug2( LDAP_DEBUG_TRACE,
"TLS trace: %s:%s\n",
op, state );
} else if ( where & SSL_CB_ALERT ) {
char *atype = (char *) SSL_alert_type_string_long( ret );
char *adesc = (char *) SSL_alert_desc_string_long( ret );
op = ( where & SSL_CB_READ ) ? "read" : "write";
#ifdef HAVE_EBCDIC
if ( atype ) {
atype = LDAP_STRDUP( atype );
__etoa( atype );
}
if ( adesc ) {
adesc = LDAP_STRDUP( adesc );
__etoa( adesc );
}
#endif
Debug3( LDAP_DEBUG_TRACE,
"TLS trace: SSL3 alert %s:%s:%s\n",
op, atype, adesc );
#ifdef HAVE_EBCDIC
if ( atype ) LDAP_FREE( atype );
if ( adesc ) LDAP_FREE( adesc );
#endif
} else if ( where & SSL_CB_EXIT ) {
if ( ret == 0 ) {
Debug2( LDAP_DEBUG_TRACE,
"TLS trace: %s:failed in %s\n",
op, state );
} else if ( ret < 0 ) {
Debug2( LDAP_DEBUG_TRACE,
"TLS trace: %s:error in %s\n",
op, state );
}
}
#ifdef HAVE_EBCDIC
if ( state ) LDAP_FREE( state );
#endif
}
static int
tlso_verify_cb( int ok, X509_STORE_CTX *ctx )
{
X509 *cert;
int errnum;
int errdepth;
X509_NAME *subject;
X509_NAME *issuer;
char *sname;
char *iname;
char *certerr = NULL;
cert = X509_STORE_CTX_get_current_cert( ctx );
errnum = X509_STORE_CTX_get_error( ctx );
errdepth = X509_STORE_CTX_get_error_depth( ctx );
/*
* X509_get_*_name return pointers to the internal copies of
* those things requested. So do not free them.
*/
subject = X509_get_subject_name( cert );
issuer = X509_get_issuer_name( cert );
/* X509_NAME_oneline, if passed a NULL buf, allocate memory */
sname = X509_NAME_oneline( subject, NULL, 0 );
iname = X509_NAME_oneline( issuer, NULL, 0 );
if ( !ok ) certerr = (char *)X509_verify_cert_error_string( errnum );
#ifdef HAVE_EBCDIC
if ( sname ) __etoa( sname );
if ( iname ) __etoa( iname );
if ( certerr ) {
certerr = LDAP_STRDUP( certerr );
__etoa( certerr );
}
#endif
Debug3( LDAP_DEBUG_TRACE,
"TLS certificate verification: depth: %d, err: %d, subject: %s,",
errdepth, errnum,
sname ? sname : "-unknown-" );
Debug1( LDAP_DEBUG_TRACE, " issuer: %s\n", iname ? iname : "-unknown-" );
if ( !ok ) {
Debug1( LDAP_DEBUG_ANY,
"TLS certificate verification: Error, %s\n",
certerr );
}
if ( sname )
OPENSSL_free ( sname );
if ( iname )
OPENSSL_free ( iname );
#ifdef HAVE_EBCDIC
if ( certerr ) LDAP_FREE( certerr );
#endif
return ok;
}
static int
tlso_verify_ok( int ok, X509_STORE_CTX *ctx )
{
(void) tlso_verify_cb( ok, ctx );
return 1;
}
/* Inspired by ERR_print_errors in OpenSSL */
static void
tlso_report_error( void )
{
unsigned long l;
char buf[200];
const char *file;
int line;
while ( ( l = ERR_get_error_line( &file, &line ) ) != 0 ) {
ERR_error_string_n( l, buf, sizeof( buf ) );
#ifdef HAVE_EBCDIC
if ( file ) {
file = LDAP_STRDUP( file );
__etoa( (char *)file );
}
__etoa( buf );
#endif
Debug3( LDAP_DEBUG_ANY, "TLS: %s %s:%d\n",
buf, file, line );
#ifdef HAVE_EBCDIC
if ( file ) LDAP_FREE( (void *)file );
#endif
}
}
#if OPENSSL_VERSION_NUMBER < 0x10100000
static RSA *
tlso_tmp_rsa_cb( SSL *ssl, int is_export, int key_length )
{
RSA *tmp_rsa;
/* FIXME: Pregenerate the key on startup */
/* FIXME: Who frees the key? */
BIGNUM *bn = BN_new();
tmp_rsa = NULL;
if ( bn ) {
if ( BN_set_word( bn, RSA_F4 )) {
tmp_rsa = RSA_new();
if ( tmp_rsa && !RSA_generate_key_ex( tmp_rsa, key_length, bn, NULL )) {
RSA_free( tmp_rsa );
tmp_rsa = NULL;
}
}
BN_free( bn );
}
if ( !tmp_rsa ) {
Debug2( LDAP_DEBUG_ANY,
"TLS: Failed to generate temporary %d-bit %s RSA key\n",
key_length, is_export ? "export" : "domestic" );
}
return tmp_rsa;
}
#endif /* OPENSSL_VERSION_NUMBER < 1.1 */
static int
tlso_seed_PRNG( const char *randfile )
{
#ifndef URANDOM_DEVICE
/* no /dev/urandom (or equiv) */
long total=0;
char buffer[MAXPATHLEN];
if (randfile == NULL) {
/* The seed file is $RANDFILE if defined, otherwise $HOME/.rnd.
* If $HOME is not set or buffer too small to hold the pathname,
* an error occurs. - From RAND_file_name() man page.
* The fact is that when $HOME is NULL, .rnd is used.
*/
randfile = RAND_file_name( buffer, sizeof( buffer ) );
}
#ifndef OPENSSL_NO_EGD
else if (RAND_egd(randfile) > 0) {
/* EGD socket */
return 0;
}
#endif
if (randfile == NULL) {
Debug0( LDAP_DEBUG_ANY,
"TLS: Use configuration file or $RANDFILE to define seed PRNG\n" );
return -1;
}
total = RAND_load_file(randfile, -1);
if (RAND_status() == 0) {
Debug0( LDAP_DEBUG_ANY,
"TLS: PRNG not been seeded with enough data\n" );
return -1;
}
/* assume if there was enough bits to seed that it's okay
* to write derived bits to the file
*/
RAND_write_file(randfile);
#endif
return 0;
}
tls_impl ldap_int_tls_impl = {
"OpenSSL",
tlso_init,
tlso_destroy,
tlso_ctx_new,
tlso_ctx_ref,
tlso_ctx_free,
tlso_ctx_init,
tlso_session_new,
tlso_session_connect,
tlso_session_accept,
tlso_session_upflags,
tlso_session_errmsg,
tlso_session_my_dn,
tlso_session_peer_dn,
tlso_session_chkhost,
tlso_session_strength,
tlso_session_unique,
tlso_session_endpoint,
tlso_session_version,
tlso_session_cipher,
tlso_session_peercert,
tlso_session_pinning,
&tlso_sbio,
#ifdef LDAP_R_COMPILE
tlso_thr_init,
#else
NULL,
#endif
0
};
#endif /* HAVE_OPENSSL */