First tentative impementation of Kerberos 5 cryptos and keys for SSL/TLS. Implemente...
[openssl.git] / ssl / s3_clnt.c
index 22e35c23fe73376fc5148c61ff8bf96a6c222006..3b3c35b9d3d84dcdd815dc524b1c74ba0628b8dc 100644 (file)
 #include <openssl/evp.h>
 #include "ssl_locl.h"
 
+#ifndef NO_KRB5
+#include "kssl.h"
+#endif
+
 static SSL_METHOD *ssl3_get_client_method(int ver);
 static int ssl3_client_hello(SSL *s);
 static int ssl3_get_server_hello(SSL *s);
 static int ssl3_get_certificate_request(SSL *s);
-static int ca_dn_cmp(X509_NAME **a,X509_NAME **b);
+static int ca_dn_cmp(const X509_NAME * const *a,const X509_NAME * const *b);
 static int ssl3_get_server_done(SSL *s);
 static int ssl3_send_client_verify(SSL *s);
 static int ssl3_send_client_certificate(SSL *s);
@@ -142,7 +146,12 @@ int ssl3_connect(SSL *s)
                        if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_START,1);
 
                        if ((s->version & 0xff00 ) != 0x0300)
-                               abort();
+                               {
+                               SSLerr(SSL_F_SSL3_CONNECT, SSL_R_INTERNAL_ERROR);
+                               ret = -1;
+                               goto end;
+                               }
+                               
                        /* s->version=SSL3_VERSION; */
                        s->type=SSL_ST_CONNECT;
 
@@ -682,6 +691,7 @@ static int ssl3_get_server_certificate(SSL *s)
        STACK_OF(X509) *sk=NULL;
        SESS_CERT *sc;
        EVP_PKEY *pkey=NULL;
+        int need_cert = 1; /* VRS: 0=> will allow null cert if auth == KRB5 */
 
        n=ssl3_get_message(s,
                SSL3_ST_CR_CERT_A,
@@ -764,6 +774,7 @@ static int ssl3_get_server_certificate(SSL *s)
                SSLerr(SSL_F_SSL3_GET_SERVER_CERTIFICATE,SSL_R_CERTIFICATE_VERIFY_FAILED);
                goto f_err; 
                }
+       ERR_clear_error(); /* but we keep s->verify_result */
 
        sc=ssl_sess_cert_new();
        if (sc == NULL) goto err;
@@ -772,12 +783,27 @@ static int ssl3_get_server_certificate(SSL *s)
        s->session->sess_cert=sc;
 
        sc->cert_chain=sk;
+       /* Inconsistency alert: cert_chain does include the peer's
+        * certificate, which we don't include in s3_srvr.c */
        x=sk_X509_value(sk,0);
        sk=NULL;
+       /* VRS 19990621: possible memory leak; sk=null ==> !sk_pop_free() @end */
 
        pkey=X509_get_pubkey(x);
 
-       if ((pkey == NULL) || EVP_PKEY_missing_parameters(pkey))
+        /* VRS: allow null cert if auth == KRB5 */
+        need_cert =
+                ((s->s3->tmp.new_cipher->algorithms & (SSL_MKEY_MASK|SSL_AUTH_MASK))
+                        == (SSL_aKRB5|SSL_kKRB5))? 0: 1;
+
+#ifdef KSSL_DEBUG
+       printf("pkey,x = %p, %p\n", pkey,x);
+       printf("ssl_cert_type(x,pkey) = %d\n", ssl_cert_type(x,pkey));
+       printf("cipher, alg, nc = %s, %lx, %d\n", s->s3->tmp.new_cipher->name,
+                s->s3->tmp.new_cipher->algorithms, need_cert);
+#endif    /* KSSL_DEBUG */
+
+       if (need_cert  &&  ((pkey == NULL) || EVP_PKEY_missing_parameters(pkey)))
                {
                x=NULL;
                al=SSL3_AL_FATAL;
@@ -786,7 +812,7 @@ static int ssl3_get_server_certificate(SSL *s)
                }
 
        i=ssl_cert_type(x,pkey);
-       if (i < 0)
+       if (need_cert && i < 0)
                {
                x=NULL;
                al=SSL3_AL_FATAL;
@@ -794,19 +820,32 @@ static int ssl3_get_server_certificate(SSL *s)
                goto f_err;
                }
 
-       sc->peer_cert_type=i;
-       CRYPTO_add(&x->references,1,CRYPTO_LOCK_X509);
-       if (sc->peer_pkeys[i].x509 != NULL) /* Why would this ever happen?
-                                                                                * We just created sc a couple of
-                                                                                * lines ago. */
-               X509_free(sc->peer_pkeys[i].x509);
-       sc->peer_pkeys[i].x509=x;
-       sc->peer_key= &(sc->peer_pkeys[i]);
-
-       if (s->session->peer != NULL)
-               X509_free(s->session->peer);
-       CRYPTO_add(&x->references,1,CRYPTO_LOCK_X509);
-       s->session->peer=x;
+        if (need_cert)
+                {
+                sc->peer_cert_type=i;
+                CRYPTO_add(&x->references,1,CRYPTO_LOCK_X509);
+                /* Why would the following ever happen?
+                 * We just created sc a couple of lines ago. */
+                if (sc->peer_pkeys[i].x509 != NULL)
+                        X509_free(sc->peer_pkeys[i].x509);
+                sc->peer_pkeys[i].x509=x;
+                sc->peer_key= &(sc->peer_pkeys[i]);
+
+                if (s->session->peer != NULL)
+                        X509_free(s->session->peer);
+                CRYPTO_add(&x->references,1,CRYPTO_LOCK_X509);
+                s->session->peer=x;
+                }
+        else
+                {
+                sc->peer_cert_type=i;
+                sc->peer_key= NULL;
+
+                if (s->session->peer != NULL)
+                        X509_free(s->session->peer);
+                s->session->peer=NULL;
+                }
+       s->session->verify_result = s->verify_result;
 
        x=NULL;
        ret=1;
@@ -932,10 +971,12 @@ static int ssl3_get_key_exchange(SSL *s)
                s->session->sess_cert->peer_rsa_tmp=rsa;
                rsa=NULL;
                }
-       else
+#else /* NO_RSA */
+       if (0)
+               ;
 #endif
 #ifndef NO_DH
-               if (alg & SSL_kEDH)
+       else if (alg & SSL_kEDH)
                {
                if ((dh=DH_new()) == NULL)
                        {
@@ -991,10 +1032,12 @@ static int ssl3_get_key_exchange(SSL *s)
 #ifndef NO_RSA
                if (alg & SSL_aRSA)
                        pkey=X509_get_pubkey(s->session->sess_cert->peer_pkeys[SSL_PKEY_RSA_ENC].x509);
-               else
+#else
+               if (0)
+                       ;
 #endif
 #ifndef NO_DSA
-               if (alg & SSL_aDSS)
+               else if (alg & SSL_aDSS)
                        pkey=X509_get_pubkey(s->session->sess_cert->peer_pkeys[SSL_PKEY_DSA_SIGN].x509);
 #endif
                /* else anonymous DH, so no certificate or pkey. */
@@ -1008,7 +1051,7 @@ static int ssl3_get_key_exchange(SSL *s)
                SSLerr(SSL_F_SSL3_GET_KEY_EXCHANGE,SSL_R_TRIED_TO_USE_UNSUPPORTED_CIPHER);
                goto f_err;
                }
-#endif
+#endif /* !NO_DH */
        if (alg & SSL_aFZA)
                {
                al=SSL_AD_HANDSHAKE_FAILURE;
@@ -1225,7 +1268,7 @@ fclose(out);
 
                if ((xn=d2i_X509_NAME(NULL,&q,l)) == NULL)
                        {
-                       /* If netscape tollerance is on, ignore errors */
+                       /* If netscape tolerance is on, ignore errors */
                        if (s->options & SSL_OP_NETSCAPE_CA_DN_BUG)
                                goto cont;
                        else
@@ -1258,7 +1301,7 @@ cont:
                ERR_clear_error();
                }
 
-       /* we should setup a certficate to return.... */
+       /* we should setup a certificate to return.... */
        s->s3->tmp.cert_req=1;
        s->s3->tmp.ctype_num=ctype_num;
        if (s->s3->tmp.ca_names != NULL)
@@ -1272,7 +1315,7 @@ err:
        return(ret);
        }
 
-static int ca_dn_cmp(X509_NAME **a, X509_NAME **b)
+static int ca_dn_cmp(const X509_NAME * const *a, const X509_NAME * const *b)
        {
        return(X509_NAME_cmp(*a,*b));
        }
@@ -1309,6 +1352,9 @@ static int ssl3_send_client_key_exchange(SSL *s)
        unsigned char *q;
        EVP_PKEY *pkey=NULL;
 #endif
+#ifndef NO_KRB5
+        KSSL_ERR kssl_err;
+#endif /* NO_KRB5 */
 
        if (s->state == SSL3_ST_CW_KEY_EXCH_A)
                {
@@ -1317,8 +1363,10 @@ static int ssl3_send_client_key_exchange(SSL *s)
 
                l=s->s3->tmp.new_cipher->algorithms;
 
+                /* Fool emacs indentation */
+                if (0) {}
 #ifndef NO_RSA
-               if (l & SSL_kRSA)
+               else if (l & SSL_kRSA)
                        {
                        RSA *rsa;
                        unsigned char tmp_buf[SSL_MAX_MASTER_KEY_LENGTH];
@@ -1375,10 +1423,75 @@ static int ssl3_send_client_key_exchange(SSL *s)
                                        tmp_buf,SSL_MAX_MASTER_KEY_LENGTH);
                        memset(tmp_buf,0,SSL_MAX_MASTER_KEY_LENGTH);
                        }
-               else
+#endif
+#ifndef NO_KRB5
+               else if (l & SSL_kKRB5)
+                        {
+                        krb5_error_code        krb5rc;
+                        KSSL_CTX       *kssl_ctx = s->kssl_ctx;
+                        krb5_data      krb5_ap_req;
+
+#ifdef KSSL_DEBUG
+                        printf("ssl3_send_client_key_exchange(%lx & %lx)\n",
+                                l, SSL_kKRB5);
+#endif /* KSSL_DEBUG */
+
+                        /*
+                        **     Tried to send random tmp_buf[] as PMS in Kerberos ticket
+                        **     by passing  krb5_mk_req_extended(ctx,authctx,opts, tmp_buf, ...)
+                        **     but: I can't retrieve the PMS on the other side!  There is
+                        **     some indication in the krb5 source that this is only used
+                        **     to generate a checksum.  OTOH, the Tung book shows data
+                        **     ("GET widget01.txt") being passed in krb5_mk_req_extended()
+                        **     by way of krb5_sendauth().  I don't get it.
+                        **     Until Kerberos goes 3DES, the big PMS secret would only be
+                        **     encrypted in 1-DES anyway.  So losing the PMS shouldn't be
+                        **     a big deal.
+                        */
+                        krb5rc = kssl_cget_tkt(kssl_ctx, &krb5_ap_req,
+                                &kssl_err);
+#ifdef KSSL_DEBUG
+                        {
+                        printf("kssl_cget_tkt rtn %d\n", krb5rc);
+                        kssl_ctx_show(kssl_ctx);
+                        if (krb5rc && kssl_err.text)
+                                printf("kssl_cget_tkt kssl_err=%s\n", kssl_err.text);
+                        }
+#endif /* KSSL_DEBUG */
+
+                        if (krb5rc)
+                                {
+                                ssl3_send_alert(s,SSL3_AL_FATAL,SSL_AD_HANDSHAKE_FAILURE);
+                                SSLerr(SSL_F_SSL3_SEND_CLIENT_KEY_EXCHANGE, kssl_err.reason);
+                                goto err;
+                                }
+
+                        /*     Send ticket (copy to *p, set n = length)
+                         */
+                        n = krb5_ap_req.length;
+                        memcpy(p, krb5_ap_req.data, krb5_ap_req.length);
+                        if (krb5_ap_req.data)  
+                                kssl_krb5_free_data_contents(NULL,&krb5_ap_req);
+
+                        /*     19991013 VRS -  3DES is kind of bogus here,
+                        **     at least until Kerberos supports 3DES.  The only
+                        **     real secret is the 8-byte Kerberos session key;
+                        **     the other key material ((s->) client_random, server_random)
+                        **     could be sniffed.  Mixing in these nonces should help
+                        **     protect against replay attacks, however.
+                        **
+                        **     Alternate code for Kerberos Purists:
+                        **
+                        **     memcpy(s->session->master_key, kssl_ctx->key, kssl_ctx->length);
+                        **     s->session->master_key_length = kssl_ctx->length;
+                        */
+                        s->session->master_key_length=
+                                s->method->ssl3_enc->generate_master_secret(s,
+                                        s->session->master_key,        kssl_ctx->key,kssl_ctx->length);
+                        }
 #endif
 #ifndef NO_DH
-               if (l & (SSL_kEDH|SSL_kDHr|SSL_kDHd))
+               else if (l & (SSL_kEDH|SSL_kDHr|SSL_kDHd))
                        {
                        DH *dh_srvr,*dh_clnt;
 
@@ -1432,8 +1545,8 @@ static int ssl3_send_client_key_exchange(SSL *s)
 
                        /* perhaps clean things up a bit EAY EAY EAY EAY*/
                        }
-               else
 #endif
+               else
                        {
                        ssl3_send_alert(s,SSL3_AL_FATAL,SSL_AD_HANDSHAKE_FAILURE);
                        SSLerr(SSL_F_SSL3_SEND_CLIENT_KEY_EXCHANGE,SSL_R_INTERNAL_ERROR);
@@ -1628,7 +1741,7 @@ static int ssl3_check_cert_and_algorithm(SSL *s)
        algs=s->s3->tmp.new_cipher->algorithms;
 
        /* we don't have a certificate */
-       if (algs & (SSL_aDH|SSL_aNULL))
+       if (algs & (SSL_aDH|SSL_aNULL|SSL_aKRB5))
                return(1);
 
 #ifndef NO_RSA