1 /* $OpenBSD: gss-genr.c,v 1.11 2006/07/22 20:48:23 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.
40 extern u_char *session_id2;
41 extern u_int session_id2_len;
43 /* Check that the OID in a data stream matches that in the context */
45 ssh_gssapi_check_oid(Gssctxt *ctx, void *data, size_t len)
47 return (ctx != NULL && ctx->oid != GSS_C_NO_OID &&
48 ctx->oid->length == len &&
49 memcmp(ctx->oid->elements, data, len) == 0);
52 /* Set the contexts OID from a data stream */
54 ssh_gssapi_set_oid_data(Gssctxt *ctx, void *data, size_t len)
56 if (ctx->oid != GSS_C_NO_OID) {
57 xfree(ctx->oid->elements);
60 ctx->oid = xmalloc(sizeof(gss_OID_desc));
61 ctx->oid->length = len;
62 ctx->oid->elements = xmalloc(len);
63 memcpy(ctx->oid->elements, data, len);
66 /* Set the contexts OID */
68 ssh_gssapi_set_oid(Gssctxt *ctx, gss_OID oid)
70 ssh_gssapi_set_oid_data(ctx, oid->elements, oid->length);
73 /* All this effort to report an error ... */
75 ssh_gssapi_error(Gssctxt *ctxt)
79 s = ssh_gssapi_last_error(ctxt, NULL, NULL);
85 ssh_gssapi_last_error(Gssctxt *ctxt, OM_uint32 *major_status,
86 OM_uint32 *minor_status)
89 gss_buffer_desc msg = GSS_C_EMPTY_BUFFER;
96 if (major_status != NULL)
97 *major_status = ctxt->major;
98 if (minor_status != NULL)
99 *minor_status = ctxt->minor;
102 /* The GSSAPI error */
104 gss_display_status(&lmin, ctxt->major,
105 GSS_C_GSS_CODE, GSS_C_NULL_OID, &ctx, &msg);
107 buffer_append(&b, msg.value, msg.length);
108 buffer_put_char(&b, '\n');
110 gss_release_buffer(&lmin, &msg);
113 /* The mechanism specific error */
115 gss_display_status(&lmin, ctxt->minor,
116 GSS_C_MECH_CODE, GSS_C_NULL_OID, &ctx, &msg);
118 buffer_append(&b, msg.value, msg.length);
119 buffer_put_char(&b, '\n');
121 gss_release_buffer(&lmin, &msg);
124 buffer_put_char(&b, '\0');
125 ret = xmalloc(buffer_len(&b));
126 buffer_get(&b, ret, buffer_len(&b));
132 * Initialise our GSSAPI context. We use this opaque structure to contain all
133 * of the data which both the client and server need to persist across
134 * {accept,init}_sec_context calls, so that when we do it from the userauth
135 * stuff life is a little easier
138 ssh_gssapi_build_ctx(Gssctxt **ctx)
140 *ctx = xcalloc(1, sizeof (Gssctxt));
141 (*ctx)->context = GSS_C_NO_CONTEXT;
142 (*ctx)->name = GSS_C_NO_NAME;
143 (*ctx)->oid = GSS_C_NO_OID;
144 (*ctx)->creds = GSS_C_NO_CREDENTIAL;
145 (*ctx)->client = GSS_C_NO_NAME;
146 (*ctx)->client_creds = GSS_C_NO_CREDENTIAL;
149 /* Delete our context, providing it has been built correctly */
151 ssh_gssapi_delete_ctx(Gssctxt **ctx)
157 if ((*ctx)->context != GSS_C_NO_CONTEXT)
158 gss_delete_sec_context(&ms, &(*ctx)->context, GSS_C_NO_BUFFER);
159 if ((*ctx)->name != GSS_C_NO_NAME)
160 gss_release_name(&ms, &(*ctx)->name);
161 if ((*ctx)->oid != GSS_C_NO_OID) {
162 xfree((*ctx)->oid->elements);
164 (*ctx)->oid = GSS_C_NO_OID;
166 if ((*ctx)->creds != GSS_C_NO_CREDENTIAL)
167 gss_release_cred(&ms, &(*ctx)->creds);
168 if ((*ctx)->client != GSS_C_NO_NAME)
169 gss_release_name(&ms, &(*ctx)->client);
170 if ((*ctx)->client_creds != GSS_C_NO_CREDENTIAL)
171 gss_release_cred(&ms, &(*ctx)->client_creds);
178 * Wrapper to init_sec_context
179 * Requires that the context contains:
181 * server name (from ssh_gssapi_import_name)
184 ssh_gssapi_init_ctx(Gssctxt *ctx, int deleg_creds, gss_buffer_desc *recv_tok,
185 gss_buffer_desc* send_tok, OM_uint32 *flags)
190 deleg_flag = GSS_C_DELEG_FLAG;
191 debug("Delegating credentials");
194 ctx->major = gss_init_sec_context(&ctx->minor,
195 GSS_C_NO_CREDENTIAL, &ctx->context, ctx->name, ctx->oid,
196 GSS_C_MUTUAL_FLAG | GSS_C_INTEG_FLAG | deleg_flag,
197 0, NULL, recv_tok, NULL, send_tok, flags, NULL);
199 if (GSS_ERROR(ctx->major))
200 ssh_gssapi_error(ctx);
205 /* Create a service name for the given host */
207 ssh_gssapi_import_name(Gssctxt *ctx, const char *host)
209 gss_buffer_desc gssbuf;
212 xasprintf(&val, "host@%s", host);
214 gssbuf.length = strlen(gssbuf.value);
216 if ((ctx->major = gss_import_name(&ctx->minor,
217 &gssbuf, GSS_C_NT_HOSTBASED_SERVICE, &ctx->name)))
218 ssh_gssapi_error(ctx);
224 /* Acquire credentials for a server running on the current host.
225 * Requires that the context structure contains a valid OID
228 /* Returns a GSSAPI error code */
230 ssh_gssapi_acquire_cred(Gssctxt *ctx)
233 char lname[MAXHOSTNAMELEN];
236 gss_create_empty_oid_set(&status, &oidset);
237 gss_add_oid_set_member(&status, ctx->oid, &oidset);
239 if (gethostname(lname, MAXHOSTNAMELEN)) {
240 gss_release_oid_set(&status, &oidset);
244 if (GSS_ERROR(ssh_gssapi_import_name(ctx, lname))) {
245 gss_release_oid_set(&status, &oidset);
249 if ((ctx->major = gss_acquire_cred(&ctx->minor,
250 ctx->name, 0, oidset, GSS_C_ACCEPT, &ctx->creds, NULL, NULL)))
251 ssh_gssapi_error(ctx);
253 gss_release_oid_set(&status, &oidset);
258 ssh_gssapi_sign(Gssctxt *ctx, gss_buffer_t buffer, gss_buffer_t hash)
260 if ((ctx->major = gss_get_mic(&ctx->minor, ctx->context,
261 GSS_C_QOP_DEFAULT, buffer, hash)))
262 ssh_gssapi_error(ctx);
268 ssh_gssapi_buildmic(Buffer *b, const char *user, const char *service,
272 buffer_put_string(b, session_id2, session_id2_len);
273 buffer_put_char(b, SSH2_MSG_USERAUTH_REQUEST);
274 buffer_put_cstring(b, user);
275 buffer_put_cstring(b, service);
276 buffer_put_cstring(b, context);
280 ssh_gssapi_server_ctx(Gssctxt **ctx, gss_OID oid)
283 ssh_gssapi_delete_ctx(ctx);
284 ssh_gssapi_build_ctx(ctx);
285 ssh_gssapi_set_oid(*ctx, oid);
286 return (ssh_gssapi_acquire_cred(*ctx));