2 * Copyright (c) 2011, JANET(UK)
5 * Redistribution and use in source and binary forms, with or without
6 * 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.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of JANET(UK) nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
21 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * Context establishment state machine.
37 #include "gssapiP_eap.h"
40 #define SM_FLAG_TRANSITED 0x80000000
42 #define SM_ASSERT_VALID(ctx, status) do { \
43 GSSEAP_ASSERT(GSS_ERROR((status)) || \
44 ((status) == GSS_S_CONTINUE_NEEDED && ((ctx)->state > GSSEAP_STATE_INITIAL && (ctx)->state < GSSEAP_STATE_ESTABLISHED)) || \
45 ((status) == GSS_S_COMPLETE && (ctx)->state == GSSEAP_STATE_ESTABLISHED)); \
50 gssEapStateToString(enum gss_eap_state state)
55 case GSSEAP_STATE_INITIAL:
58 case GSSEAP_STATE_AUTHENTICATE:
61 case GSSEAP_STATE_INITIATOR_EXTS:
64 case GSSEAP_STATE_ACCEPTOR_EXTS:
67 #ifdef GSSEAP_ENABLE_REAUTH
68 case GSSEAP_STATE_REAUTHENTICATE:
72 case GSSEAP_STATE_ESTABLISHED:
84 gssEapSmTransition(gss_ctx_id_t ctx, enum gss_eap_state state)
86 GSSEAP_ASSERT(state >= GSSEAP_STATE_INITIAL);
87 GSSEAP_ASSERT(state <= GSSEAP_STATE_ESTABLISHED);
89 fprintf(stderr, "GSS-EAP: state transition %s->%s\n",
90 gssEapStateToString(GSSEAP_SM_STATE(ctx)),
91 gssEapStateToString(state));
95 #endif /* GSSEAP_DEBUG */
98 makeErrorToken(OM_uint32 *minor,
99 OM_uint32 majorStatus,
100 OM_uint32 minorStatus,
101 struct gss_eap_token_buffer_set *token)
103 OM_uint32 major, tmpMinor;
104 unsigned char errorData[8];
105 gss_buffer_desc errorBuffer;
107 GSSEAP_ASSERT(GSS_ERROR(majorStatus));
110 * Only return error codes that the initiator could have caused,
111 * to avoid information leakage.
113 if (IS_RADIUS_ERROR(minorStatus)) {
114 /* Squash RADIUS error codes */
115 minorStatus = GSSEAP_RADIUS_PROT_FAILURE;
116 } else if (!IS_WIRE_ERROR(minorStatus)) {
117 /* Don't return non-wire error codes */
118 return GSS_S_COMPLETE;
121 minorStatus -= ERROR_TABLE_BASE_eapg;
123 store_uint32_be(majorStatus, &errorData[0]);
124 store_uint32_be(minorStatus, &errorData[4]);
126 major = gssEapAllocInnerTokens(&tmpMinor, 1, token);
127 if (GSS_ERROR(major)) {
132 errorBuffer.length = sizeof(errorData);
133 errorBuffer.value = errorData;
135 major = duplicateBuffer(&tmpMinor, &errorBuffer, &token->buffers.elements[0]);
136 if (GSS_ERROR(major)) {
137 gssEapReleaseInnerTokens(&tmpMinor, token, 1);
142 token->buffers.count = 1;
143 token->types[0] = ITOK_TYPE_CONTEXT_ERR | ITOK_FLAG_CRITICAL;
146 return GSS_S_COMPLETE;
150 gssEapSmStep(OM_uint32 *minor,
157 gss_channel_bindings_t chanBindings,
158 gss_buffer_t inputToken,
159 gss_buffer_t outputToken,
160 struct gss_eap_sm *sm, /* ordered by state */
163 OM_uint32 major, tmpMajor, tmpMinor;
164 struct gss_eap_token_buffer_set inputTokens = { { 0, GSS_C_NO_BUFFER }, NULL };
165 struct gss_eap_token_buffer_set outputTokens = { { 0, GSS_C_NO_BUFFER }, NULL };
166 gss_buffer_desc unwrappedInputToken = GSS_C_EMPTY_BUFFER;
167 gss_buffer_desc unwrappedOutputToken = GSS_C_EMPTY_BUFFER;
168 unsigned int smFlags = 0;
170 int initialContextToken = 0;
171 enum gss_eap_token_type tokType;
173 GSSEAP_ASSERT(smCount > 0);
177 outputToken->length = 0;
178 outputToken->value = NULL;
180 if (inputToken != GSS_C_NO_BUFFER && inputToken->length != 0) {
181 major = gssEapVerifyToken(minor, ctx, inputToken, &tokType,
182 &unwrappedInputToken);
183 if (GSS_ERROR(major))
186 if (tokType != (CTX_IS_INITIATOR(ctx)
187 ? TOK_TYPE_ACCEPTOR_CONTEXT : TOK_TYPE_INITIATOR_CONTEXT)) {
188 major = GSS_S_DEFECTIVE_TOKEN;
189 *minor = GSSEAP_WRONG_TOK_ID;
192 } else if (!CTX_IS_INITIATOR(ctx) || ctx->state != GSSEAP_STATE_INITIAL) {
193 major = GSS_S_DEFECTIVE_TOKEN;
194 *minor = GSSEAP_WRONG_SIZE;
197 initialContextToken = 1;
200 if (CTX_IS_ESTABLISHED(ctx)) {
201 major = GSS_S_BAD_STATUS;
202 *minor = GSSEAP_CONTEXT_ESTABLISHED;
206 GSSEAP_ASSERT(ctx->state < GSSEAP_STATE_ESTABLISHED);
208 major = gssEapDecodeInnerTokens(minor, &unwrappedInputToken, &inputTokens);
209 if (GSS_ERROR(major))
212 major = gssEapAllocInnerTokens(minor, smCount, &outputTokens);
213 if (GSS_ERROR(major))
216 ctx->inputTokens = &inputTokens;
217 ctx->outputTokens = &outputTokens;
219 /* Process all the tokens that are valid for the current state. */
220 for (i = 0; i < smCount; i++) {
221 struct gss_eap_sm *smp = &sm[i];
222 int processToken = 0;
223 gss_buffer_t innerInputToken = GSS_C_NO_BUFFER;
224 OM_uint32 *inputTokenType = NULL;
225 gss_buffer_desc innerOutputToken = GSS_C_EMPTY_BUFFER;
227 if ((smp->validStates & ctx->state) == 0)
231 * We special case the first call to gss_init_sec_context so that
232 * all token providers have the opportunity to generate an initial
233 * context token. Providers where inputTokenType is ITOK_TYPE_NONE
234 * are always called and generally act on state transition boundaries,
235 * for example to advance the state after a series of optional tokens
236 * (as is the case with the extension token exchange) or to generate
237 * a new token after the state was advanced by a provider which did
240 if (smp->inputTokenType == ITOK_TYPE_NONE || initialContextToken) {
242 } else if ((smFlags & SM_FLAG_TRANSITED) == 0) {
243 /* Don't regurgitate a token which belonds to a previous state. */
244 for (j = 0; j < inputTokens.buffers.count; j++) {
245 if ((inputTokens.types[j] & ITOK_TYPE_MASK) == smp->inputTokenType) {
247 /* Check for duplicate inner tokens */
248 major = GSS_S_DEFECTIVE_TOKEN;
249 *minor = GSSEAP_DUPLICATE_ITOK;
253 innerInputToken = &inputTokens.buffers.elements[j];
254 inputTokenType = &inputTokens.types[j];
257 if (GSS_ERROR(major))
262 enum gss_eap_state oldState = ctx->state;
265 if (inputTokenType != NULL && (*inputTokenType & ITOK_FLAG_CRITICAL))
266 smFlags |= SM_FLAG_INPUT_TOKEN_CRITICAL;
268 major = smp->processToken(minor, cred, ctx, target, mech, reqFlags,
269 timeReq, chanBindings, innerInputToken,
270 &innerOutputToken, &smFlags);
271 if (GSS_ERROR(major))
274 if (inputTokenType != NULL)
275 *inputTokenType |= ITOK_FLAG_VERIFIED;
276 if (ctx->state < oldState)
278 else if (ctx->state != oldState)
279 smFlags |= SM_FLAG_TRANSITED;
281 if (innerOutputToken.value != NULL) {
282 outputTokens.buffers.elements[outputTokens.buffers.count] = innerOutputToken;
283 GSSEAP_ASSERT(smp->outputTokenType != ITOK_TYPE_NONE);
284 outputTokens.types[outputTokens.buffers.count] = smp->outputTokenType;
285 if (smFlags & SM_FLAG_OUTPUT_TOKEN_CRITICAL)
286 outputTokens.types[outputTokens.buffers.count] |= ITOK_FLAG_CRITICAL;
287 outputTokens.buffers.count++;
290 * Break out if we made a state transition and have some tokens to send.
292 if ((smFlags & SM_FLAG_TRANSITED) &&
293 ((smFlags & SM_FLAG_FORCE_SEND_TOKEN) || outputTokens.buffers.count != 0)) {
294 SM_ASSERT_VALID(ctx, major);
297 } else if ((smp->itokFlags & SM_ITOK_FLAG_REQUIRED) &&
298 smp->inputTokenType != ITOK_TYPE_NONE) {
299 /* Check for required inner tokens */
300 major = GSS_S_DEFECTIVE_TOKEN;
301 *minor = GSSEAP_MISSING_REQUIRED_ITOK;
306 GSSEAP_ASSERT(outputTokens.buffers.count <= smCount);
308 /* Check we understood all critical tokens sent by peer */
309 if (!GSS_ERROR(major)) {
310 for (j = 0; j < inputTokens.buffers.count; j++) {
311 if ((inputTokens.types[j] & ITOK_FLAG_CRITICAL) &&
312 (inputTokens.types[j] & ITOK_FLAG_VERIFIED) == 0) {
313 major = GSS_S_UNAVAILABLE;
314 *minor = GSSEAP_CRIT_ITOK_UNAVAILABLE;
320 /* Optionaly emit an error token if we are the acceptor */
321 if (GSS_ERROR(major)) {
322 if (CTX_IS_INITIATOR(ctx))
323 goto cleanup; /* return error directly to caller */
325 /* replace any emitted tokens with error token */
326 gssEapReleaseInnerTokens(&tmpMinor, &outputTokens, 1);
328 tmpMajor = makeErrorToken(&tmpMinor, major, *minor, &outputTokens);
329 if (GSS_ERROR(tmpMajor)) {
336 /* Format output token from inner tokens */
337 if (outputTokens.buffers.count != 0 || /* inner tokens to send */
338 !CTX_IS_INITIATOR(ctx) || /* any leg acceptor */
339 !CTX_IS_ESTABLISHED(ctx)) { /* non-last leg initiator */
340 tmpMajor = gssEapEncodeInnerTokens(&tmpMinor, &outputTokens, &unwrappedOutputToken);
341 if (tmpMajor == GSS_S_COMPLETE) {
342 if (CTX_IS_INITIATOR(ctx))
343 tokType = TOK_TYPE_INITIATOR_CONTEXT;
345 tokType = TOK_TYPE_ACCEPTOR_CONTEXT;
347 tmpMajor = gssEapMakeToken(&tmpMinor, ctx, &unwrappedOutputToken,
348 tokType, outputToken);
349 if (GSS_ERROR(tmpMajor)) {
357 /* If the context is established, empty tokens only to be emitted by initiator */
358 GSSEAP_ASSERT(!CTX_IS_ESTABLISHED(ctx) || ((outputToken->length == 0) == CTX_IS_INITIATOR(ctx)));
360 SM_ASSERT_VALID(ctx, major);
363 gssEapReleaseInnerTokens(&tmpMinor, &inputTokens, 0);
364 gssEapReleaseInnerTokens(&tmpMinor, &inputTokens, 1);
366 gss_release_buffer(&tmpMinor, &unwrappedOutputToken);
368 ctx->inputTokens = NULL;
369 ctx->outputTokens = NULL;