gss_pseudo_random for krb5

git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@20051 ec53bebd-3082-4978-b11e-865c3cabbd6b

lib/gssapi/krb5/prf.c

@@ -0,0 +1,137 @@
+/*
+ * Copyright (c) 2007 Kungliga Tekniska H<>gskolan
+ * (Royal Institute of Technology, Stockholm, Sweden). 
+ * All rights reserved. 
+ *
+ * Redistribution and use in source and binary forms, with or without 
+ * modification, are permitted provided that the following conditions 
+ * are met: 
+ *
+ * 1. Redistributions of source code must retain the above copyright 
+ *    notice, this list of conditions and the following disclaimer. 
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright 
+ *    notice, this list of conditions and the following disclaimer in the 
+ *    documentation and/or other materials provided with the distribution. 
+ *
+ * 3. Neither the name of the Institute nor the names of its contributors 
+ *    may be used to endorse or promote products derived from this software 
+ *    without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND 
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE 
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 
+ * SUCH DAMAGE. 
+ */
+
+#include "krb5/gsskrb5_locl.h"
+
+RCSID("$Id$");
+
+OM_uint32
+_gsskrb5_pseudo_random(OM_uint32 *minor_status,
+		       gss_ctx_id_t context_handle,
+		       int prf_key,
+		       const gss_buffer_t prf_in,
+		       ssize_t desired_output_len,
+		       gss_buffer_t prf_out)
+{
+    gsskrb5_ctx ctx = (gsskrb5_ctx)context_handle;
+    krb5_context context;
+    krb5_error_code ret;
+    krb5_crypto crypto;
+    krb5_data input, output;
+    uint32_t num;
+    unsigned char *p;
+    krb5_keyblock *key = NULL;
+
+    if (ctx == NULL) {
+	*minor_status = 0;
+	return GSS_S_NO_CONTEXT;
+    }
+
+    GSSAPI_KRB5_INIT (&context);
+
+    switch(prf_key) {
+    case GSS_C_PRF_KEY_FULL:
+	_gsskrb5i_get_acceptor_subkey(ctx, context, &key);
+    case GSS_C_PRF_KEY_PARTIAL:
+	_gsskrb5i_get_initiator_subkey(ctx, context, &key);
+	break;
+    default:
+	_gsskrb5_set_status("unknown kerberos prf_key");
+	*minor_status = 0;
+	return GSS_S_FAILURE;
+    }
+
+    if (key == NULL) {
+	_gsskrb5_set_status("no prf_key found");
+	*minor_status = 0;
+	return GSS_S_FAILURE;
+    }
+
+    ret = krb5_crypto_init(context, key, 0, &crypto);
+    krb5_free_keyblock (context, key);
+    if (ret) {
+	*minor_status = ret;
+	return GSS_S_FAILURE;
+    }
+
+    prf_out->value = malloc(desired_output_len);
+    if (prf_out->value == NULL) {
+	_gsskrb5_set_status("Out of memory");
+	*minor_status = GSS_KRB5_S_KG_INPUT_TOO_LONG;
+	krb5_crypto_destroy(context, crypto);
+	return GSS_S_FAILURE;
+    }
+    prf_out->length = desired_output_len;
+
+    HEIMDAL_MUTEX_lock(&ctx->ctx_id_mutex);
+
+    input.length = prf_in->length + 4;
+    input.data = malloc(prf_in->length + 4);
+    if (input.data == NULL) {
+	OM_uint32 junk;
+	_gsskrb5_set_status("Out of memory");
+	*minor_status = GSS_KRB5_S_KG_INPUT_TOO_LONG;
+	gss_release_buffer(&junk, prf_out);
+	krb5_crypto_destroy(context, crypto);
+	HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex);
+	return GSS_S_FAILURE;
+    }
+    memcpy(((unsigned char *)input.data) + 4, prf_in->value, prf_in->length);
+
+    num = 0;
+    p = prf_out->value;
+    while(desired_output_len > 0) {
+	_gsskrb5_encode_om_uint32(num, input.data);
+	ret = krb5_crypto_prf(context, crypto, &input, &output);
+	if (ret) {
+	    OM_uint32 junk;
+	    *minor_status = ret;
+	    free(input.data);
+	    gss_release_buffer(&junk, prf_out);
+	    krb5_crypto_destroy(context, crypto);
+	    HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex);
+	    return GSS_S_FAILURE;
+	}
+	memcpy(p, output.data, MIN(desired_output_len, output.length));
+	p += output.length;
+	desired_output_len -= output.length;
+	krb5_data_free(&output);
+	num++;
+    }
+
+    krb5_crypto_destroy(context, crypto);
+
+    HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex);
+
+    return GSS_S_COMPLETE;
+}