[openssh.git] / gss-genr.c

/*	$OpenBSD: gss-genr.c,v 1.1 2003/08/22 10:56:09 markus Exp $	*/

/*
 * Copyright (c) 2001-2003 Simon Wilkinson. 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR `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 AUTHOR 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 "includes.h"

#ifdef GSSAPI

#include "xmalloc.h"
#include "bufaux.h"
#include "compat.h"
#include "log.h"
#include "monitor_wrap.h"

#include "ssh-gss.h"


/* Check that the OID in a data stream matches that in the context */
int
ssh_gssapi_check_oid(Gssctxt *ctx, void *data, size_t len)
{
	return (ctx != NULL && ctx->oid != GSS_C_NO_OID &&
	    ctx->oid->length == len &&
	    memcmp(ctx->oid->elements, data, len) == 0);
}

/* Set the contexts OID from a data stream */
void
ssh_gssapi_set_oid_data(Gssctxt *ctx, void *data, size_t len)
{
	if (ctx->oid != GSS_C_NO_OID) {
		xfree(ctx->oid->elements);
		xfree(ctx->oid);
	}
	ctx->oid = xmalloc(sizeof(gss_OID_desc));
	ctx->oid->length = len;
	ctx->oid->elements = xmalloc(len);
	memcpy(ctx->oid->elements, data, len);
}

/* Set the contexts OID */
void
ssh_gssapi_set_oid(Gssctxt *ctx, gss_OID oid)
{
	ssh_gssapi_set_oid_data(ctx, oid->elements, oid->length);
}

/* All this effort to report an error ... */
void
ssh_gssapi_error(Gssctxt *ctxt)
{
	debug("%s", ssh_gssapi_last_error(ctxt, NULL, NULL));
}

char *
ssh_gssapi_last_error(Gssctxt *ctxt,
		      OM_uint32 *major_status, OM_uint32 *minor_status)
{
	OM_uint32 lmin;
	gss_buffer_desc msg = GSS_C_EMPTY_BUFFER;
	OM_uint32 ctx;
	Buffer b;
	char *ret;

	buffer_init(&b);

	if (major_status != NULL)
		*major_status = ctxt->major;
	if (minor_status != NULL)
		*minor_status = ctxt->minor;

	ctx = 0;
	/* The GSSAPI error */
	do {
		gss_display_status(&lmin, ctxt->major,
		    GSS_C_GSS_CODE, GSS_C_NULL_OID, &ctx, &msg);

		buffer_append(&b, msg.value, msg.length);
		buffer_put_char(&b, '\n');

		gss_release_buffer(&lmin, &msg);
	} while (ctx != 0);

	/* The mechanism specific error */
	do {
		gss_display_status(&lmin, ctxt->minor,
		    GSS_C_MECH_CODE, GSS_C_NULL_OID, &ctx, &msg);

		buffer_append(&b, msg.value, msg.length);
		buffer_put_char(&b, '\n');

		gss_release_buffer(&lmin, &msg);
	} while (ctx != 0);

	buffer_put_char(&b, '\0');
	ret = xmalloc(buffer_len(&b));
	buffer_get(&b, ret, buffer_len(&b));
	buffer_free(&b);
	return (ret);
}

/*
 * Initialise our GSSAPI context. We use this opaque structure to contain all
 * of the data which both the client and server need to persist across
 * {accept,init}_sec_context calls, so that when we do it from the userauth
 * stuff life is a little easier
 */
void
ssh_gssapi_build_ctx(Gssctxt **ctx)
{
	*ctx = xmalloc(sizeof (Gssctxt));
	(*ctx)->major = 0;
	(*ctx)->minor = 0;
	(*ctx)->context = GSS_C_NO_CONTEXT;
	(*ctx)->name = GSS_C_NO_NAME;
	(*ctx)->oid = GSS_C_NO_OID;
	(*ctx)->creds = GSS_C_NO_CREDENTIAL;
	(*ctx)->client = GSS_C_NO_NAME;
	(*ctx)->client_creds = GSS_C_NO_CREDENTIAL;
}

/* Delete our context, providing it has been built correctly */
void
ssh_gssapi_delete_ctx(Gssctxt **ctx)
{
	OM_uint32 ms;

	if ((*ctx) == NULL)
		return;
	if ((*ctx)->context != GSS_C_NO_CONTEXT)
		gss_delete_sec_context(&ms, &(*ctx)->context, GSS_C_NO_BUFFER);
	if ((*ctx)->name != GSS_C_NO_NAME)
		gss_release_name(&ms, &(*ctx)->name);
	if ((*ctx)->oid != GSS_C_NO_OID) {
		xfree((*ctx)->oid->elements);
		xfree((*ctx)->oid);
		(*ctx)->oid = GSS_C_NO_OID;
	}
	if ((*ctx)->creds != GSS_C_NO_CREDENTIAL)
		gss_release_cred(&ms, &(*ctx)->creds);
	if ((*ctx)->client != GSS_C_NO_NAME)
		gss_release_name(&ms, &(*ctx)->client);
	if ((*ctx)->client_creds != GSS_C_NO_CREDENTIAL)
		gss_release_cred(&ms, &(*ctx)->client_creds);

	xfree(*ctx);
	*ctx = NULL;
}

/*
 * Wrapper to init_sec_context
 * Requires that the context contains:
 *	oid
 *	server name (from ssh_gssapi_import_name)
 */
OM_uint32
ssh_gssapi_init_ctx(Gssctxt *ctx, int deleg_creds, gss_buffer_desc *recv_tok,
    gss_buffer_desc* send_tok, OM_uint32 *flags)
{
	int deleg_flag = 0;

	if (deleg_creds) {
		deleg_flag = GSS_C_DELEG_FLAG;
		debug("Delegating credentials");
	}

	ctx->major = gss_init_sec_context(&ctx->minor,
	    GSS_C_NO_CREDENTIAL, &ctx->context, ctx->name, ctx->oid,
	    GSS_C_MUTUAL_FLAG | GSS_C_INTEG_FLAG | deleg_flag,
	    0, NULL, recv_tok, NULL, send_tok, flags, NULL);

	if (GSS_ERROR(ctx->major))
		ssh_gssapi_error(ctx);

	return (ctx->major);
}

/* Create a service name for the given host */
OM_uint32
ssh_gssapi_import_name(Gssctxt *ctx, const char *host)
{
	gss_buffer_desc gssbuf;

	gssbuf.length = sizeof("host@") + strlen(host);
	gssbuf.value = xmalloc(gssbuf.length);
	snprintf(gssbuf.value, gssbuf.length, "host@%s", host);

	if ((ctx->major = gss_import_name(&ctx->minor,
	    &gssbuf, GSS_C_NT_HOSTBASED_SERVICE, &ctx->name)))
		ssh_gssapi_error(ctx);

	xfree(gssbuf.value);
	return (ctx->major);
}

/* Acquire credentials for a server running on the current host.
 * Requires that the context structure contains a valid OID
 */

/* Returns a GSSAPI error code */
OM_uint32
ssh_gssapi_acquire_cred(Gssctxt *ctx)
{
	OM_uint32 status;
	char lname[MAXHOSTNAMELEN];
	gss_OID_set oidset;

	gss_create_empty_oid_set(&status, &oidset);
	gss_add_oid_set_member(&status, ctx->oid, &oidset);

	if (gethostname(lname, MAXHOSTNAMELEN))
		return (-1);

	if (GSS_ERROR(ssh_gssapi_import_name(ctx, lname)))
		return (ctx->major);

	if ((ctx->major = gss_acquire_cred(&ctx->minor,
	    ctx->name, 0, oidset, GSS_C_ACCEPT, &ctx->creds, NULL, NULL)))
		ssh_gssapi_error(ctx);

	gss_release_oid_set(&status, &oidset);
	return (ctx->major);
}

OM_uint32
ssh_gssapi_server_ctx(Gssctxt **ctx, gss_OID oid) {
	if (*ctx)
		ssh_gssapi_delete_ctx(ctx);
	ssh_gssapi_build_ctx(ctx);
	ssh_gssapi_set_oid(*ctx, oid);
	return (ssh_gssapi_acquire_cred(*ctx));
}

#endif /* GSSAPI */
Commit	Line	Data
7364bd04	1	/* $OpenBSD: gss-genr.c,v 1.1 2003/08/22 10:56:09 markus Exp $ */
	2
	3	/*
	4	* Copyright (c) 2001-2003 Simon Wilkinson. All rights reserved.
	5	*
	6	* Redistribution and use in source and binary forms, with or without
	7	* modification, are permitted provided that the following conditions
	8	* are met:
	9	* 1. Redistributions of source code must retain the above copyright
	10	* notice, this list of conditions and the following disclaimer.
	11	* 2. Redistributions in binary form must reproduce the above copyright
	12	* notice, this list of conditions and the following disclaimer in the
	13	* documentation and/or other materials provided with the distribution.
	14	*
	15	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR `AS IS'' AND ANY EXPRESS OR
	16	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
	17	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
	18	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
	19	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
	20	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	21	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	22	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	23	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
	24	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	25	*/
	26
	27	#include "includes.h"
	28
	29	#ifdef GSSAPI
	30
	31	#include "xmalloc.h"
	32	#include "bufaux.h"
	33	#include "compat.h"
	34	#include "log.h"
	35	#include "monitor_wrap.h"
	36
	37	#include "ssh-gss.h"
	38
	39
	40	/* Check that the OID in a data stream matches that in the context */
	41	int
	42	ssh_gssapi_check_oid(Gssctxt ctx, void data, size_t len)
	43	{
	44	return (ctx != NULL && ctx->oid != GSS_C_NO_OID &&
	45	ctx->oid->length == len &&
	46	memcmp(ctx->oid->elements, data, len) == 0);
	47	}
	48
	49	/* Set the contexts OID from a data stream */
	50	void
	51	ssh_gssapi_set_oid_data(Gssctxt ctx, void data, size_t len)
	52	{
	53	if (ctx->oid != GSS_C_NO_OID) {
	54	xfree(ctx->oid->elements);
	55	xfree(ctx->oid);
	56	}
	57	ctx->oid = xmalloc(sizeof(gss_OID_desc));
	58	ctx->oid->length = len;
	59	ctx->oid->elements = xmalloc(len);
	60	memcpy(ctx->oid->elements, data, len);
	61	}
	62
	63	/* Set the contexts OID */
	64	void
65	ssh_gssapi_set_oid(Gssctxt *ctx, gss_OID oid)
66	{
67	ssh_gssapi_set_oid_data(ctx, oid->elements, oid->length);
68	}
69
70	/* All this effort to report an error ... */
71	void
72	ssh_gssapi_error(Gssctxt *ctxt)
73	{
74	debug("%s", ssh_gssapi_last_error(ctxt, NULL, NULL));
75	}
76
77	char *
78	ssh_gssapi_last_error(Gssctxt *ctxt,
79	OM_uint32 major_status, OM_uint32 minor_status)
80	{
81	OM_uint32 lmin;
82	gss_buffer_desc msg = GSS_C_EMPTY_BUFFER;
83	OM_uint32 ctx;
84	Buffer b;
85	char *ret;
86
87	buffer_init(&b);
88
89	if (major_status != NULL)
90	*major_status = ctxt->major;
91	if (minor_status != NULL)
92	*minor_status = ctxt->minor;
93
94	ctx = 0;
95	/* The GSSAPI error */
96	do {
97	gss_display_status(&lmin, ctxt->major,
98	GSS_C_GSS_CODE, GSS_C_NULL_OID, &ctx, &msg);
99
100	buffer_append(&b, msg.value, msg.length);
101	buffer_put_char(&b, '\n');
102
103	gss_release_buffer(&lmin, &msg);
104	} while (ctx != 0);
105
106	/* The mechanism specific error */
107	do {
108	gss_display_status(&lmin, ctxt->minor,
109	GSS_C_MECH_CODE, GSS_C_NULL_OID, &ctx, &msg);
110
111	buffer_append(&b, msg.value, msg.length);
112	buffer_put_char(&b, '\n');
113
114	gss_release_buffer(&lmin, &msg);
115	} while (ctx != 0);
116
117	buffer_put_char(&b, '\0');
118	ret = xmalloc(buffer_len(&b));
119	buffer_get(&b, ret, buffer_len(&b));
120	buffer_free(&b);
121	return (ret);
122	}
123
124	/*
125	* Initialise our GSSAPI context. We use this opaque structure to contain all
126	* of the data which both the client and server need to persist across
127	* {accept,init}_sec_context calls, so that when we do it from the userauth
128	* stuff life is a little easier
129	*/
130	void
131	ssh_gssapi_build_ctx(Gssctxt **ctx)
132	{
133	*ctx = xmalloc(sizeof (Gssctxt));
134	(*ctx)->major = 0;
135	(*ctx)->minor = 0;
136	(*ctx)->context = GSS_C_NO_CONTEXT;
137	(*ctx)->name = GSS_C_NO_NAME;
138	(*ctx)->oid = GSS_C_NO_OID;
139	(*ctx)->creds = GSS_C_NO_CREDENTIAL;
140	(*ctx)->client = GSS_C_NO_NAME;
141	(*ctx)->client_creds = GSS_C_NO_CREDENTIAL;
142	}
143
144	/* Delete our context, providing it has been built correctly */
145	void
146	ssh_gssapi_delete_ctx(Gssctxt **ctx)
147	{
148	OM_uint32 ms;
149
150	if ((*ctx) == NULL)
151	return;
152	if ((*ctx)->context != GSS_C_NO_CONTEXT)
153	gss_delete_sec_context(&ms, &(*ctx)->context, GSS_C_NO_BUFFER);
154	if ((*ctx)->name != GSS_C_NO_NAME)
155	gss_release_name(&ms, &(*ctx)->name);
156	if ((*ctx)->oid != GSS_C_NO_OID) {
157	xfree((*ctx)->oid->elements);
158	xfree((*ctx)->oid);
159	(*ctx)->oid = GSS_C_NO_OID;
160	}
161	if ((*ctx)->creds != GSS_C_NO_CREDENTIAL)
162	gss_release_cred(&ms, &(*ctx)->creds);
163	if ((*ctx)->client != GSS_C_NO_NAME)
164	gss_release_name(&ms, &(*ctx)->client);
165	if ((*ctx)->client_creds != GSS_C_NO_CREDENTIAL)
166	gss_release_cred(&ms, &(*ctx)->client_creds);
167
168	xfree(*ctx);
169	*ctx = NULL;
170	}
171
172	/*
173	* Wrapper to init_sec_context
174	* Requires that the context contains:
175	* oid
176	* server name (from ssh_gssapi_import_name)
177	*/
178	OM_uint32
179	ssh_gssapi_init_ctx(Gssctxt ctx, int deleg_creds, gss_buffer_desc recv_tok,
180	gss_buffer_desc* send_tok, OM_uint32 *flags)
181	{
182	int deleg_flag = 0;
183
184	if (deleg_creds) {
185	deleg_flag = GSS_C_DELEG_FLAG;
186	debug("Delegating credentials");
187	}
188
189	ctx->major = gss_init_sec_context(&ctx->minor,
190	GSS_C_NO_CREDENTIAL, &ctx->context, ctx->name, ctx->oid,
191	GSS_C_MUTUAL_FLAG \| GSS_C_INTEG_FLAG \| deleg_flag,
192	0, NULL, recv_tok, NULL, send_tok, flags, NULL);
193
194	if (GSS_ERROR(ctx->major))
195	ssh_gssapi_error(ctx);
196
197	return (ctx->major);
198	}
199
200	/* Create a service name for the given host */
201	OM_uint32
202	ssh_gssapi_import_name(Gssctxt ctx, const char host)
203	{
204	gss_buffer_desc gssbuf;
205
206	gssbuf.length = sizeof("host@") + strlen(host);
207	gssbuf.value = xmalloc(gssbuf.length);
208	snprintf(gssbuf.value, gssbuf.length, "host@%s", host);
209
210	if ((ctx->major = gss_import_name(&ctx->minor,
211	&gssbuf, GSS_C_NT_HOSTBASED_SERVICE, &ctx->name)))
212	ssh_gssapi_error(ctx);
213
214	xfree(gssbuf.value);
215	return (ctx->major);
216	}
217
218	/* Acquire credentials for a server running on the current host.
219	* Requires that the context structure contains a valid OID
220	*/
221
222	/* Returns a GSSAPI error code */
223	OM_uint32
224	ssh_gssapi_acquire_cred(Gssctxt *ctx)
225	{
226	OM_uint32 status;
227	char lname[MAXHOSTNAMELEN];
228	gss_OID_set oidset;
229
230	gss_create_empty_oid_set(&status, &oidset);
231	gss_add_oid_set_member(&status, ctx->oid, &oidset);
232
233	if (gethostname(lname, MAXHOSTNAMELEN))
234	return (-1);
235
236	if (GSS_ERROR(ssh_gssapi_import_name(ctx, lname)))
237	return (ctx->major);
238
239	if ((ctx->major = gss_acquire_cred(&ctx->minor,
240	ctx->name, 0, oidset, GSS_C_ACCEPT, &ctx->creds, NULL, NULL)))
241	ssh_gssapi_error(ctx);
242
243	gss_release_oid_set(&status, &oidset);
244	return (ctx->major);
245	}
246
247	OM_uint32
248	ssh_gssapi_server_ctx(Gssctxt **ctx, gss_OID oid) {
249	if (*ctx)
250	ssh_gssapi_delete_ctx(ctx);
251	ssh_gssapi_build_ctx(ctx);
252	ssh_gssapi_set_oid(*ctx, oid);
253	return (ssh_gssapi_acquire_cred(*ctx));
254	}
255
256	#endif /* GSSAPI */