Add impersonate.

git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@17615 ec53bebd-3082-4978-b11e-865c3cabbd6b

lib/krb5/get_cred.c

@@ -142,6 +142,7 @@ init_tgs_req (krb5_context context,
 	      krb5_creds *in_creds,
 	      krb5_creds *krbtgt,
 	      unsigned nonce,
+	      const METHOD_DATA *padata,
 	      krb5_keyblock **subkey,
 	      TGS_REQ *t,
 	      krb5_key_usage usage)
@@ -220,12 +221,22 @@ init_tgs_req (krb5_context context,
 	krb5_set_error_string(context, "malloc: out of memory");
 	goto fail;
     }
-    ALLOC_SEQ(t->padata, 1);
+    ALLOC_SEQ(t->padata, 1 + padata->len);
     if (t->padata->val == NULL) {
 	ret = ENOMEM;
 	krb5_set_error_string(context, "malloc: out of memory");
 	goto fail;
     }
+    {
+	int i;
+	for (i = 0; i < padata->len; i++) {
+	    ret = copy_PA_DATA(&padata->val[i], &t->padata->val[i + 1]);
+	    if (ret) {
+		krb5_set_error_string(context, "malloc: out of memory");
+		goto fail;
+	    }
+	}
+    }
 
     {
 	krb5_auth_context ac;
@@ -268,7 +279,7 @@ init_tgs_req (krb5_context context,
 	ret = make_pa_tgs_req(context,
 			      ac,
 			      &t->req_body, 
-			      t->padata->val,
+			      &t->padata->val[0],
 			      krbtgt,
 			      usage);
 	if(ret) {
@@ -385,6 +396,7 @@ get_cred_kdc_usage(krb5_context context,
 		   krb5_addresses *addresses, 
 		   krb5_creds *in_creds,
 		   krb5_creds *krbtgt,
+		   krb5_principal impersonate_principal,
 		   krb5_creds *out_creds,
 		   krb5_key_usage usage)
 {
@@ -399,9 +411,12 @@ get_cred_kdc_usage(krb5_context context,
     size_t len;
     Ticket second_ticket;
     int send_to_kdc_flags = 0;
+    METHOD_DATA padata;
     
     krb5_data_zero(&resp);
     krb5_data_zero(&enc);
+    padata.val = NULL;
+    padata.len = 0;
 
     krb5_generate_random_block(&nonce, sizeof(nonce));
     nonce &= 0xffffffff;
@@ -414,6 +429,58 @@ get_cred_kdc_usage(krb5_context context,
 	    return ret;
     }
 
+
+    if (impersonate_principal) {
+	krb5_crypto crypto;
+	PA_S4U2Self self;
+	krb5_data data;
+	void *buf;
+	size_t size;
+
+	self.name = impersonate_principal->name;
+	self.realm = impersonate_principal->realm;
+	self.auth = estrdup("Kerberos");
+	
+	ret = _krb5_s4u2self_to_checksumdata(context, &self, &data);
+	if (ret) {
+	    free(self.auth);
+	    goto out;
+	}
+
+	ret = krb5_crypto_init(context, &krbtgt->session, 0, &crypto);
+	if (ret) {
+	    free(self.auth);
+	    krb5_data_free(&data);
+	    goto out;
+	}
+
+	ret = krb5_create_checksum(context,
+				   crypto,
+				   KRB5_KU_TGS_IMPERSONATE,
+				   0,
+				   data.data,
+				   data.length, 
+				   &self.cksum);
+	krb5_crypto_destroy(context, crypto);
+	krb5_data_free(&data);
+	if (ret) {
+	    free(self.auth);
+	    goto out;
+	}
+
+	ASN1_MALLOC_ENCODE(PA_S4U2Self, buf, len, &self, &size, ret);
+	free(self.auth);
+	free_Checksum(&self.cksum);
+	if (ret)
+	    goto out;
+	if (len != size)
+	    krb5_abortx(context, "internal asn1 error");
+	
+	ret = krb5_padata_add(context, &padata, KRB5_PADATA_S4U2SELF, buf, len);
+	if (ret)
+	    goto out;
+    }
+
     ret = init_tgs_req (context,
 			id,
 			addresses,
@@ -422,11 +489,14 @@ get_cred_kdc_usage(krb5_context context,
 			in_creds,
 			krbtgt,
 			nonce,
+			&padata,
 			&subkey, 
 			&req,
 			usage);
-    if(flags.b.enc_tkt_in_skey)
+    if(flags.b.enc_tkt_in_skey) {
+	free_METHOD_DATA(&padata);
 	free_Ticket(&second_ticket);
+    }
     if (ret)
 	goto out;
 
@@ -475,7 +545,7 @@ again:
 				   &krbtgt->addresses,
 				   nonce,
 				   TRUE,
-				   flags.b.request_anonymous,
+				   TRUE /* flags.b.request_anonymous */,
 				   decrypt_tkt_with_subkey,
 				   subkey);
 	krb5_free_kdc_rep(context, &rep);
@@ -497,6 +567,7 @@ again:
     }
 
 out:
+    free_METHOD_DATA(&padata);
     krb5_data_free(&resp);
     krb5_data_free(&enc);
     if(subkey){
@@ -514,16 +585,19 @@ get_cred_kdc(krb5_context context,
 	     krb5_addresses *addresses, 
 	     krb5_creds *in_creds, 
 	     krb5_creds *krbtgt,
+	     krb5_principal impersonate_principal,
 	     krb5_creds *out_creds)
 {
     krb5_error_code ret;
 
     ret = get_cred_kdc_usage(context, id, flags, addresses, in_creds,
-			     krbtgt, out_creds, KRB5_KU_TGS_REQ_AUTH);
+			     krbtgt, impersonate_principal, out_creds,
+			     KRB5_KU_TGS_REQ_AUTH);
     if (ret == KRB5KRB_AP_ERR_BAD_INTEGRITY) {
 	krb5_clear_error_string (context);
 	ret = get_cred_kdc_usage(context, id, flags, addresses, in_creds,
-				 krbtgt, out_creds, KRB5_KU_AP_REQ_AUTH);
+				 krbtgt, impersonate_principal, out_creds, 
+				 KRB5_KU_AP_REQ_AUTH);
     }
     return ret;
 }
@@ -533,7 +607,7 @@ get_cred_kdc(krb5_context context,
 static krb5_error_code
 get_cred_kdc_la(krb5_context context, krb5_ccache id, krb5_kdc_flags flags, 
 		krb5_creds *in_creds, krb5_creds *krbtgt, 
-		krb5_creds *out_creds)
+		krb5_principal impersonate_principal, krb5_creds *out_creds)
 {
     krb5_error_code ret;
     krb5_addresses addresses, *addrs = &addresses;
@@ -543,7 +617,7 @@ get_cred_kdc_la(krb5_context context, krb5_ccache id, krb5_kdc_flags flags,
     if(addresses.len == 0)
 	addrs = NULL;
     ret = get_cred_kdc(context, id, flags, addrs, 
-		       in_creds, krbtgt, out_creds);
+		       in_creds, krbtgt, impersonate_principal, out_creds);
     krb5_free_addresses(context, &addresses);
     return ret;
 }
@@ -575,7 +649,7 @@ krb5_get_kdc_cred(krb5_context context,
 	return ret;
     }
     ret = get_cred_kdc(context, id, flags, addresses, 
-		       in_creds, krbtgt, *out_creds);
+		       in_creds, krbtgt, NULL, *out_creds);
     krb5_free_creds (context, krbtgt);
     if(ret)
 	free(*out_creds);
@@ -607,7 +681,17 @@ find_cred(krb5_context context,
 	}
 	tgts++;
     }
+    {
+	char *str;
+	ret = krb5_unparse_name(context, server, &str);
+	if(ret == 0) {
+	    krb5_set_error_string(context, "Matching credential "
+				  "(%s) not found", str);
+	    free(str);
+	} else {
 	    krb5_clear_error_string(context);
+	}
+    }
     return KRB5_CC_NOTFOUND;
 }
 
@@ -650,6 +734,7 @@ get_cred_from_kdc_flags(krb5_context context,
 			krb5_kdc_flags flags,
 			krb5_ccache ccache,
 			krb5_creds *in_creds,
+			krb5_principal impersonate_principal,
 			krb5_creds **out_creds,
 			krb5_creds ***ret_tgts)
 {
@@ -707,10 +792,12 @@ get_cred_from_kdc_flags(krb5_context context,
 
 		if (noaddr)
 		    ret = get_cred_kdc(context, ccache, flags, NULL,
-				       in_creds, &tgts, *out_creds);
+				       in_creds, &tgts,
+				       impersonate_principal, *out_creds);
 		else
 		    ret = get_cred_kdc_la(context, ccache, flags, 
-					  in_creds, &tgts, *out_creds);
+					  in_creds, &tgts, 
+					  impersonate_principal, *out_creds);
 		if (ret) {
 		    free (*out_creds);
 		    *out_creds = NULL;
@@ -731,7 +818,7 @@ get_cred_from_kdc_flags(krb5_context context,
 	heim_general_string tgt_inst;
 
 	ret = get_cred_from_kdc_flags(context, flags, ccache, &tmp_creds, 
-				      &tgt, ret_tgts);
+				      NULL, &tgt, ret_tgts);
 	if(ret) {
 	    krb5_free_principal(context, tmp_creds.server);
 	    krb5_free_principal(context, tmp_creds.client);
@@ -776,10 +863,10 @@ get_cred_from_kdc_flags(krb5_context context,
 				&noaddr);
 	if (noaddr)
 	    ret = get_cred_kdc (context, ccache, flags, NULL,
-				in_creds, tgt, *out_creds);
+				in_creds, tgt, NULL, *out_creds);
 	else
 	    ret = get_cred_kdc_la(context, ccache, flags, 
-				  in_creds, tgt, *out_creds);
+				  in_creds, tgt, NULL, *out_creds);
 	if (ret) {
 	    free (*out_creds);
 	    *out_creds = NULL;
@@ -800,7 +887,7 @@ krb5_get_cred_from_kdc_opt(krb5_context context,
     krb5_kdc_flags f;
     f.i = flags;
     return get_cred_from_kdc_flags(context, f, ccache, 
-				   in_creds, out_creds, ret_tgts);
+				   in_creds, NULL, out_creds, ret_tgts);
 }
 
 krb5_error_code KRB5_LIB_FUNCTION
@@ -879,15 +966,18 @@ krb5_get_credentials_with_flags(krb5_context context,
     }
     if(options & KRB5_GC_USER_USER)
 	flags.b.enc_tkt_in_skey = 1;
+    if (flags.b.enc_tkt_in_skey)
+	options |= KRB5_GC_NO_STORE;
+
     tgts = NULL;
     ret = get_cred_from_kdc_flags(context, flags, ccache, 
-				  in_creds, out_creds, &tgts);
+				  in_creds, NULL, out_creds, &tgts);
     for(i = 0; tgts && tgts[i]; i++) {
 	krb5_cc_store_cred(context, ccache, tgts[i]);
 	krb5_free_creds(context, tgts[i]);
     }
     free(tgts);
-    if(ret == 0 && flags.b.enc_tkt_in_skey == 0)
+    if(ret == 0 && (options & KRB5_GC_NO_STORE) == 0)
 	krb5_cc_store_cred(context, ccache, *out_creds);
     return ret;
 }
@@ -904,3 +994,167 @@ krb5_get_credentials(krb5_context context,
     return krb5_get_credentials_with_flags(context, options, flags,
 					   ccache, in_creds, out_creds);
 }
+
+struct krb5_get_creds_opt_data {
+    krb5_principal self;
+    krb5_flags options;
+    krb5_enctype enctype;
+};
+
+
+krb5_error_code KRB5_LIB_FUNCTION
+krb5_get_creds_opt_alloc(krb5_context context, krb5_get_creds_opt *opt)
+{
+    *opt = calloc(1, sizeof(**opt));
+    if (*opt == NULL) {
+	krb5_set_error_string(context, "malloc: out of memory");
+	return ENOMEM;
+    }
+    return 0;
+}
+
+void KRB5_LIB_FUNCTION
+krb5_get_creds_opt_free(krb5_context context, krb5_get_creds_opt opt)
+{
+    if (opt->self)
+	krb5_free_principal(context, opt->self);
+    memset(opt, 0, sizeof(*opt));
+    free(opt);
+}
+
+void KRB5_LIB_FUNCTION
+krb5_get_creds_opt_set_options(krb5_context context,
+			       krb5_get_creds_opt opt,
+			       krb5_flags options)
+{
+    opt->options = options;
+}
+
+void KRB5_LIB_FUNCTION
+krb5_get_creds_opt_add_options(krb5_context context,
+			       krb5_get_creds_opt opt,
+			       krb5_flags options)
+{
+    opt->options |= options;
+}
+
+
+void KRB5_LIB_FUNCTION
+krb5_get_creds_opt_set_enctype(krb5_context context,
+			       krb5_get_creds_opt opt,
+			       krb5_enctype enctype)
+{
+    opt->enctype = enctype;
+}
+
+
+krb5_error_code KRB5_LIB_FUNCTION
+krb5_get_creds_opt_set_impersonate(krb5_context context,
+				   krb5_get_creds_opt opt,
+				   krb5_const_principal self)
+{
+    if (opt->self)
+	krb5_free_principal(context, opt->self);
+    return krb5_copy_principal(context, self, &opt->self);
+}
+
+krb5_error_code KRB5_LIB_FUNCTION
+krb5_get_creds(krb5_context context,
+	       krb5_get_creds_opt opt,
+	       krb5_ccache ccache,
+	       krb5_const_principal inprinc,
+	       krb5_creds **out_creds)
+{
+    krb5_kdc_flags flags;
+    krb5_flags options;
+    krb5_creds in_creds;
+    krb5_error_code ret;
+    krb5_creds **tgts;
+    krb5_creds *res_creds;
+    int i;
+    
+    memset(&in_creds, 0, sizeof(in_creds));
+    in_creds.server = rk_UNCONST(inprinc);
+
+    ret = krb5_cc_get_principal(context, ccache, &in_creds.client);
+    if (ret)
+	return ret;
+
+    options = opt->options;
+    flags.i = 0;
+
+    *out_creds = NULL;
+    res_creds = calloc(1, sizeof(*res_creds));
+    if (res_creds == NULL) {
+	krb5_free_principal(context, in_creds.client);
+	krb5_set_error_string(context, "malloc: out of memory");
+	return ENOMEM;
+    }
+
+    if (opt->enctype) {
+	in_creds.session.keytype = opt->enctype;
+	options |= KRB5_TC_MATCH_KEYTYPE;
+    }
+
+    /* 
+     * If we got a credential, check if credential is expired before
+     * returning it.
+     */
+    ret = krb5_cc_retrieve_cred(context,
+                                ccache,
+				opt->enctype ? KRB5_TC_MATCH_KEYTYPE : 0,
+                                &in_creds, res_creds);
+    /* 
+     * If we got a credential, check if credential is expired before
+     * returning it, but only if KRB5_GC_EXPIRED_OK is not set.
+     */
+    if (ret == 0) {
+	krb5_timestamp timeret;
+
+	/* If expired ok, don't bother checking */
+        if(options & KRB5_GC_EXPIRED_OK) {
+            *out_creds = res_creds;
+	    krb5_free_principal(context, in_creds.client);
+            return 0;
+        }
+	    
+	krb5_timeofday(context, &timeret);
+	if(res_creds->times.endtime > timeret) {
+	    *out_creds = res_creds;
+	    krb5_free_principal(context, in_creds.client);
+	    return 0;
+	}
+	if(options & KRB5_GC_CACHED)
+	    krb5_cc_remove_cred(context, ccache, 0, res_creds);
+
+    } else if(ret != KRB5_CC_END) {
+        free(res_creds);
+	krb5_free_principal(context, in_creds.client);
+        return ret;
+    }
+    free(res_creds);
+    if(options & KRB5_GC_CACHED) {
+        krb5_clear_error_string (context);        
+	krb5_free_principal(context, in_creds.client);
+        return KRB5_CC_NOTFOUND;
+    }
+    if(options & KRB5_GC_USER_USER) {
+	flags.b.enc_tkt_in_skey = 1;
+	options |= KRB5_GC_NO_STORE;
+    }
+    if (options & KRB5_GC_FORWARDABLE)
+	flags.b.forwardable = 1;
+
+    tgts = NULL;
+    ret = get_cred_from_kdc_flags(context, flags, ccache, 
+				  &in_creds, opt->self, out_creds, &tgts);
+    krb5_free_principal(context, in_creds.client);
+    for(i = 0; tgts && tgts[i]; i++) {
+	krb5_cc_store_cred(context, ccache, tgts[i]);
+	krb5_free_creds(context, tgts[i]);
+    }
+    free(tgts);
+    if(ret == 0 && (options & KRB5_GC_NO_STORE) == 0)
+	krb5_cc_store_cred(context, ccache, *out_creds);
+    return ret;
+}