GSS-API backend for the unified security framework.

git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@4673 ec53bebd-3082-4978-b11e-865c3cabbd6b

appl/ftp/ftp/gssapi.c

@@ -0,0 +1,305 @@
+/*
+ * Copyright (c) 1998 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. All advertising materials mentioning features or use of this software 
+ *    must display the following acknowledgement: 
+ *      This product includes software developed by Kungliga Tekniska 
+ *      H<>gskolan and its contributors. 
+ *
+ * 4. 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. 
+ */
+
+#ifdef FTP_SERVER
+#include "ftpd_locl.h"
+#else
+#include "ftp_locl.h"
+#endif
+#include <gssapi.h>
+
+RCSID("$Id$");
+
+struct gss_data {
+    gss_ctx_id_t context_hdl;
+};
+
+static int
+gss_init(void *app_data)
+{
+    struct gss_data *d = app_data;
+    d->context_hdl = GSS_C_NO_CONTEXT;
+    return 0;
+}
+
+static int
+gss_check_prot(void *app_data, int level)
+{
+    if(level == prot_confidential)
+	return -1;
+    return 0;
+}
+
+static int
+gss_decode(void *app_data, void *buf, int len, int level)
+{
+    OM_uint32 maj_stat, min_stat;
+    gss_buffer_desc input, output;
+    gss_qop_t qop_state;
+    int conf_state;
+    struct gss_data *d = app_data;
+
+    input.length = len;
+    input.value = buf;
+    maj_stat = gss_unwrap (&min_stat,
+			   d->context_hdl,
+			   &input,
+			   &output,
+			   &conf_state,
+			   &qop_state);
+    if(GSS_ERROR(maj_stat)) {
+	printf("Error unwrapping GSS packet: %x, %d, len = %d.\n", 
+	       maj_stat, min_stat, len);
+	abort();
+    }
+    memmove(buf, output.value, output.length);
+    return output.length;
+}
+
+static int
+gss_overhead(void *app_data, int level, int len)
+{
+    return 100; /* dunno? */
+}
+
+
+static int
+gss_encode(void *app_data, void *from, int length, int level, void **to)
+{
+    OM_uint32 maj_stat, min_stat;
+    gss_buffer_desc input, output;
+    int conf_state;
+    struct gss_data *d = app_data;
+
+    input.length = length;
+    input.value = from;
+    maj_stat = gss_wrap (&min_stat,
+			 d->context_hdl,
+			 level == prot_private,
+			 GSS_C_QOP_DEFAULT,
+			 &input,
+			 &conf_state,
+			 &output);
+    *to = output.value;
+    return output.length;
+}
+
+/* end common stuff */
+
+#ifdef FTP_SERVER
+
+static int
+gss_adat(void *app_data, void *buf, size_t len)
+{
+    char *p = NULL;
+    gss_buffer_desc input_token, output_token;
+    OM_uint32 maj_stat, min_stat;
+    gss_name_t client_name;
+    struct gss_data *d = app_data;
+
+    gss_channel_bindings_t bindings = malloc(sizeof(*bindings));
+    bindings->initiator_addrtype = GSS_C_AF_INET;
+    bindings->initiator_address.length = 4;
+    bindings->initiator_address.value = &his_addr.sin_addr;
+    bindings->acceptor_addrtype = GSS_C_AF_INET;
+    bindings->acceptor_address.length = 4;
+    bindings->acceptor_address.value = &ctrl_addr.sin_addr;
+    bindings->application_data.length = 0;
+    bindings->application_data.value = NULL;
+
+    input_token.value = buf;
+    input_token.length = len;
+    
+    maj_stat = gss_accept_sec_context (&min_stat,
+				       &d->context_hdl,
+				       GSS_C_NO_CREDENTIAL,
+				       &input_token,
+				       bindings,
+				       &client_name,
+				       NULL,
+				       &output_token,
+				       NULL,
+				       NULL,
+				       NULL);
+
+    if(output_token.length) {
+	if(base64_encode(output_token.value, output_token.length, &p) < 0) {
+	    reply(535, "Out of memory base64-encoding.");
+	    return -1;
+	}
+    }
+    if(maj_stat == GSS_S_COMPLETE){
+	if(p)
+	    reply(235, "ADAT=%s", p);
+	else
+	    reply(235, "ADAT Complete");
+	sec_complete = 1;
+    } else if(maj_stat == GSS_S_CONTINUE_NEEDED)
+	if(p)
+	    reply(335, "ADAT=%s", p);
+	else
+	    reply(335, "OK, need more data");
+    else
+	reply(535, "foo?");
+    free(p);
+    return 0;
+}
+
+static int
+gss_userok()
+{
+    return 0;
+}
+
+struct sec_server_mech gss_server_mech = {
+    "GSSAPI",
+    sizeof(struct gss_data),
+    gss_init, /* init */
+    NULL, /* end */
+    gss_check_prot,
+    gss_overhead,
+    gss_encode,
+    gss_decode,
+    /* */
+    NULL,
+    gss_adat,
+    NULL, /* pbsz */
+    NULL, /* ccc */
+    gss_userok
+};
+
+#else
+
+extern struct sockaddr_in hisctladdr, myctladdr;
+
+static int
+gss_auth(void *app_data, char *host)
+{
+    
+    OM_uint32 maj_stat, min_stat;
+    gss_buffer_desc name;
+    gss_name_t target_name;
+    gss_buffer_desc input, output_token;
+    int context_established = 0;
+    char *p;
+    int n;
+    gss_channel_bindings_t bindings;
+    struct gss_data *d = app_data;
+	    
+    name.length = asprintf((char**)&name.value, "ftp@%s", host);
+    maj_stat = gss_import_name(&min_stat,
+			       &name,
+			       GSS_C_NT_HOSTBASED_SERVICE,
+			       &target_name);
+    free(name.value);
+    
+
+    input.length = 0;
+    input.value = NULL;
+
+    bindings = malloc(sizeof(*bindings));
+    bindings->initiator_addrtype = GSS_C_AF_INET;
+    bindings->initiator_address.length = 4;
+    bindings->initiator_address.value = &hisctladdr.sin_addr;
+    bindings->acceptor_addrtype = GSS_C_AF_INET;
+    bindings->acceptor_address.length = 4;
+    bindings->acceptor_address.value = &myctladdr.sin_addr;
+    bindings->application_data.length = 0;
+    bindings->application_data.value = NULL;
+
+    while(!context_established) {
+	maj_stat = gss_init_sec_context(&min_stat,
+					GSS_C_NO_CREDENTIAL,
+					&d->context_hdl,
+					target_name,
+					GSS_C_NO_OID,
+					GSS_C_MUTUAL_FLAG | GSS_C_SEQUENCE_FLAG,
+					0,
+					bindings,
+					&input,
+					NULL,
+					&output_token,
+					NULL,
+					NULL);
+	if (GSS_ERROR(maj_stat))
+	    abort ();
+	gss_release_buffer(&min_stat, &input);
+	if (output_token.length != 0) {
+	    base64_encode(output_token.value, output_token.length, &p);
+	    gss_release_buffer(&min_stat, &output_token);
+	    n = command("ADAT %s", p);
+	    free(p);
+	}
+	if (GSS_ERROR(maj_stat)) {
+	    if (d->context_hdl != GSS_C_NO_CONTEXT)
+		gss_delete_sec_context (&min_stat,
+					&d->context_hdl,
+					GSS_C_NO_BUFFER);
+	    break;
+	}
+	if (maj_stat & GSS_S_CONTINUE_NEEDED) {
+	    p = strstr(reply_string, "ADAT=");
+	    if(p == NULL){
+		abort();
+	    } else {
+		p+=5;
+		input.value = malloc(strlen(p));
+		input.length = base64_decode(p, input.value);
+	    }
+	} else {
+	    if(code != 235)
+		abort();
+	    context_established = 1;
+	}
+    }
+    return 0;
+}
+
+struct sec_client_mech gss_client_mech = {
+    "GSSAPI",
+    sizeof(struct gss_data),
+    gss_init,
+    gss_auth,
+    NULL, /* end */
+    gss_check_prot,
+    gss_overhead,
+    gss_encode,
+    gss_decode,
+};
+
+#endif