1 /* $OpenBSD: gss-genr.c,v 1.6 2005/10/13 22:24:31 stevesk Exp $ */
4 * Copyright (c) 2001-2003 Simon Wilkinson. All rights reserved.
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
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.
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.
38 extern u_char *session_id2;
39 extern u_int session_id2_len;
41 /* Check that the OID in a data stream matches that in the context */
43 ssh_gssapi_check_oid(Gssctxt *ctx, void *data, size_t len)
45 return (ctx != NULL && ctx->oid != GSS_C_NO_OID &&
46 ctx->oid->length == len &&
47 memcmp(ctx->oid->elements, data, len) == 0);
50 /* Set the contexts OID from a data stream */
52 ssh_gssapi_set_oid_data(Gssctxt *ctx, void *data, size_t len)
54 if (ctx->oid != GSS_C_NO_OID) {
55 xfree(ctx->oid->elements);
58 ctx->oid = xmalloc(sizeof(gss_OID_desc));
59 ctx->oid->length = len;
60 ctx->oid->elements = xmalloc(len);
61 memcpy(ctx->oid->elements, data, len);
64 /* Set the contexts OID */
66 ssh_gssapi_set_oid(Gssctxt *ctx, gss_OID oid)
68 ssh_gssapi_set_oid_data(ctx, oid->elements, oid->length);
71 /* All this effort to report an error ... */
73 ssh_gssapi_error(Gssctxt *ctxt)
75 debug("%s", ssh_gssapi_last_error(ctxt, NULL, NULL));
79 ssh_gssapi_last_error(Gssctxt *ctxt, OM_uint32 *major_status,
80 OM_uint32 *minor_status)
83 gss_buffer_desc msg = GSS_C_EMPTY_BUFFER;
90 if (major_status != NULL)
91 *major_status = ctxt->major;
92 if (minor_status != NULL)
93 *minor_status = ctxt->minor;
96 /* The GSSAPI error */
98 gss_display_status(&lmin, ctxt->major,
99 GSS_C_GSS_CODE, GSS_C_NULL_OID, &ctx, &msg);
101 buffer_append(&b, msg.value, msg.length);
102 buffer_put_char(&b, '\n');
104 gss_release_buffer(&lmin, &msg);
107 /* The mechanism specific error */
109 gss_display_status(&lmin, ctxt->minor,
110 GSS_C_MECH_CODE, GSS_C_NULL_OID, &ctx, &msg);
112 buffer_append(&b, msg.value, msg.length);
113 buffer_put_char(&b, '\n');
115 gss_release_buffer(&lmin, &msg);
118 buffer_put_char(&b, '\0');
119 ret = xmalloc(buffer_len(&b));
120 buffer_get(&b, ret, buffer_len(&b));
126 * Initialise our GSSAPI context. We use this opaque structure to contain all
127 * of the data which both the client and server need to persist across
128 * {accept,init}_sec_context calls, so that when we do it from the userauth
129 * stuff life is a little easier
132 ssh_gssapi_build_ctx(Gssctxt **ctx)
134 *ctx = xmalloc(sizeof (Gssctxt));
137 (*ctx)->context = GSS_C_NO_CONTEXT;
138 (*ctx)->name = GSS_C_NO_NAME;
139 (*ctx)->oid = GSS_C_NO_OID;
140 (*ctx)->creds = GSS_C_NO_CREDENTIAL;
141 (*ctx)->client = GSS_C_NO_NAME;
142 (*ctx)->client_creds = GSS_C_NO_CREDENTIAL;
145 /* Delete our context, providing it has been built correctly */
147 ssh_gssapi_delete_ctx(Gssctxt **ctx)
153 if ((*ctx)->context != GSS_C_NO_CONTEXT)
154 gss_delete_sec_context(&ms, &(*ctx)->context, GSS_C_NO_BUFFER);
155 if ((*ctx)->name != GSS_C_NO_NAME)
156 gss_release_name(&ms, &(*ctx)->name);
157 if ((*ctx)->oid != GSS_C_NO_OID) {
158 xfree((*ctx)->oid->elements);
160 (*ctx)->oid = GSS_C_NO_OID;
162 if ((*ctx)->creds != GSS_C_NO_CREDENTIAL)
163 gss_release_cred(&ms, &(*ctx)->creds);
164 if ((*ctx)->client != GSS_C_NO_NAME)
165 gss_release_name(&ms, &(*ctx)->client);
166 if ((*ctx)->client_creds != GSS_C_NO_CREDENTIAL)
167 gss_release_cred(&ms, &(*ctx)->client_creds);
174 * Wrapper to init_sec_context
175 * Requires that the context contains:
177 * server name (from ssh_gssapi_import_name)
180 ssh_gssapi_init_ctx(Gssctxt *ctx, int deleg_creds, gss_buffer_desc *recv_tok,
181 gss_buffer_desc* send_tok, OM_uint32 *flags)
186 deleg_flag = GSS_C_DELEG_FLAG;
187 debug("Delegating credentials");
190 ctx->major = gss_init_sec_context(&ctx->minor,
191 GSS_C_NO_CREDENTIAL, &ctx->context, ctx->name, ctx->oid,
192 GSS_C_MUTUAL_FLAG | GSS_C_INTEG_FLAG | deleg_flag,
193 0, NULL, recv_tok, NULL, send_tok, flags, NULL);
195 if (GSS_ERROR(ctx->major))
196 ssh_gssapi_error(ctx);
201 /* Create a service name for the given host */
203 ssh_gssapi_import_name(Gssctxt *ctx, const char *host)
205 gss_buffer_desc gssbuf;
207 gssbuf.length = sizeof("host@") + strlen(host);
208 gssbuf.value = xmalloc(gssbuf.length);
209 snprintf(gssbuf.value, gssbuf.length, "host@%s", host);
211 if ((ctx->major = gss_import_name(&ctx->minor,
212 &gssbuf, GSS_C_NT_HOSTBASED_SERVICE, &ctx->name)))
213 ssh_gssapi_error(ctx);
219 /* Acquire credentials for a server running on the current host.
220 * Requires that the context structure contains a valid OID
223 /* Returns a GSSAPI error code */
225 ssh_gssapi_acquire_cred(Gssctxt *ctx)
228 char lname[MAXHOSTNAMELEN];
231 gss_create_empty_oid_set(&status, &oidset);
232 gss_add_oid_set_member(&status, ctx->oid, &oidset);
234 if (gethostname(lname, MAXHOSTNAMELEN))
237 if (GSS_ERROR(ssh_gssapi_import_name(ctx, lname)))
240 if ((ctx->major = gss_acquire_cred(&ctx->minor,
241 ctx->name, 0, oidset, GSS_C_ACCEPT, &ctx->creds, NULL, NULL)))
242 ssh_gssapi_error(ctx);
244 gss_release_oid_set(&status, &oidset);
249 ssh_gssapi_sign(Gssctxt *ctx, gss_buffer_t buffer, gss_buffer_t hash)
251 if ((ctx->major = gss_get_mic(&ctx->minor, ctx->context,
252 GSS_C_QOP_DEFAULT, buffer, hash)))
253 ssh_gssapi_error(ctx);
259 ssh_gssapi_buildmic(Buffer *b, const char *user, const char *service,
263 buffer_put_string(b, session_id2, session_id2_len);
264 buffer_put_char(b, SSH2_MSG_USERAUTH_REQUEST);
265 buffer_put_cstring(b, user);
266 buffer_put_cstring(b, service);
267 buffer_put_cstring(b, context);
271 ssh_gssapi_server_ctx(Gssctxt **ctx, gss_OID oid)
274 ssh_gssapi_delete_ctx(ctx);
275 ssh_gssapi_build_ctx(ctx);
276 ssh_gssapi_set_oid(*ctx, oid);
277 return (ssh_gssapi_acquire_cred(*ctx));