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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 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 case GSSEAP_STATE_REAUTHENTICATE:
70 case GSSEAP_STATE_ESTABLISHED:
82 gssEapSmTransition(gss_ctx_id_t ctx, enum gss_eap_state state)
84 assert(state >= GSSEAP_STATE_INITIAL);
85 assert(state <= GSSEAP_STATE_ESTABLISHED);
87 fprintf(stderr, "GSS-EAP: state transition %s->%s\n",
88 gssEapStateToString(GSSEAP_SM_STATE(ctx)),
89 gssEapStateToString(state));
93 #endif /* GSSEAP_DEBUG */
96 makeErrorToken(OM_uint32 *minor,
97 OM_uint32 majorStatus,
98 OM_uint32 minorStatus,
99 gss_buffer_set_t *outputToken)
102 unsigned char errorData[8];
103 gss_buffer_desc errorBuffer;
105 assert(GSS_ERROR(majorStatus));
107 major = gss_create_empty_buffer_set(minor, outputToken);
108 if (GSS_ERROR(major))
112 * Only return error codes that the initiator could have caused,
113 * to avoid information leakage.
115 if (IS_RADIUS_ERROR(minorStatus)) {
116 /* Squash RADIUS error codes */
117 minorStatus = GSSEAP_RADIUS_PROT_FAILURE;
118 } else if (!IS_WIRE_ERROR(minorStatus)) {
119 /* Don't return non-wire error codes */
120 return GSS_S_COMPLETE;
123 minorStatus -= ERROR_TABLE_BASE_eapg;
125 store_uint32_be(majorStatus, &errorData[0]);
126 store_uint32_be(minorStatus, &errorData[4]);
128 errorBuffer.length = sizeof(errorData);
129 errorBuffer.value = errorData;
131 major = gss_add_buffer_set_member(minor, &errorBuffer, outputToken);
132 if (GSS_ERROR(major))
135 return GSS_S_COMPLETE;
139 allocInnerTokens(OM_uint32 *minor,
141 gss_buffer_set_t *pTokens,
142 OM_uint32 **pTokenTypes)
144 OM_uint32 major, tmpMinor;
145 gss_buffer_set_t tokens = GSS_C_NO_BUFFER_SET;
146 OM_uint32 *tokenTypes = NULL;
148 major = gss_create_empty_buffer_set(minor, &tokens);
149 if (GSS_ERROR(major))
152 assert(tokens->count == 0);
153 assert(tokens->elements == NULL);
155 tokens->elements = (gss_buffer_desc *)GSSEAP_CALLOC(count, sizeof(gss_buffer_desc));
156 if (tokens->elements == NULL) {
157 major = GSS_S_FAILURE;
162 tokenTypes = (OM_uint32 *)GSSEAP_CALLOC(count, sizeof(OM_uint32));
163 if (tokenTypes == NULL) {
164 major = GSS_S_FAILURE;
169 major = GSS_S_COMPLETE;
173 if (GSS_ERROR(major)) {
174 gss_release_buffer_set(&tmpMinor, &tokens);
175 tokens = GSS_C_NO_BUFFER_SET;
176 if (tokenTypes != NULL) {
177 GSSEAP_FREE(tokenTypes);
183 *pTokenTypes = tokenTypes;
189 gssEapSmStep(OM_uint32 *minor,
196 gss_channel_bindings_t chanBindings,
197 gss_buffer_t inputToken,
198 gss_buffer_t outputToken,
199 struct gss_eap_sm *sm, /* ordered by state */
202 OM_uint32 major, tmpMajor, tmpMinor;
203 gss_buffer_desc unwrappedInputToken = GSS_C_EMPTY_BUFFER;
204 gss_buffer_desc unwrappedOutputToken = GSS_C_EMPTY_BUFFER;
205 gss_buffer_set_t innerInputTokens = GSS_C_NO_BUFFER_SET;
206 gss_buffer_set_t innerOutputTokens = GSS_C_NO_BUFFER_SET;
207 OM_uint32 *inputTokenTypes = NULL, *outputTokenTypes = NULL;
208 unsigned int smFlags = 0;
210 int initialContextToken = 0;
211 enum gss_eap_token_type tokType;
217 outputToken->length = 0;
218 outputToken->value = NULL;
220 if (inputToken != GSS_C_NO_BUFFER && inputToken->length != 0) {
221 major = gssEapVerifyToken(minor, ctx, inputToken, &tokType,
222 &unwrappedInputToken);
223 if (GSS_ERROR(major))
226 if (tokType != (CTX_IS_INITIATOR(ctx)
227 ? TOK_TYPE_ACCEPTOR_CONTEXT : TOK_TYPE_INITIATOR_CONTEXT)) {
228 major = GSS_S_DEFECTIVE_TOKEN;
229 *minor = GSSEAP_WRONG_TOK_ID;
232 } else if (!CTX_IS_INITIATOR(ctx) || ctx->state != GSSEAP_STATE_INITIAL) {
233 major = GSS_S_DEFECTIVE_TOKEN;
234 *minor = GSSEAP_WRONG_SIZE;
237 initialContextToken = 1;
240 if (CTX_IS_ESTABLISHED(ctx)) {
241 major = GSS_S_BAD_STATUS;
242 *minor = GSSEAP_CONTEXT_ESTABLISHED;
246 assert(ctx->state < GSSEAP_STATE_ESTABLISHED);
248 major = gssEapDecodeInnerTokens(minor, &unwrappedInputToken,
249 &innerInputTokens, &inputTokenTypes);
250 if (GSS_ERROR(major))
253 assert(innerInputTokens != GSS_C_NO_BUFFER_SET);
255 major = allocInnerTokens(minor, smCount, &innerOutputTokens, &outputTokenTypes);
256 if (GSS_ERROR(major))
259 /* Process all the tokens that are valid for the current state. */
260 for (i = 0; i < smCount; i++) {
261 struct gss_eap_sm *smp = &sm[i];
262 int processToken = 0;
263 gss_buffer_t innerInputToken = GSS_C_NO_BUFFER;
264 OM_uint32 *inputTokenType = NULL;
265 gss_buffer_desc innerOutputToken = GSS_C_EMPTY_BUFFER;
267 if ((smp->validStates & ctx->state) == 0)
271 * We special case the first call to gss_init_sec_context so that
272 * all token providers have the opportunity to generate an initial
273 * context token. Providers where inputTokenType is ITOK_TYPE_NONE
274 * are always called and generally act on state transition boundaries,
275 * for example to advance the state after a series of optional tokens
276 * (as is the case with the extension token exchange) or to generate
277 * a new token after the state was advanced by a provider which did
280 if (smp->inputTokenType == ITOK_TYPE_NONE || initialContextToken) {
282 } else if ((smFlags & SM_FLAG_TRANSITED) == 0) {
283 /* Don't regurgitate a token which belonds to a previous state. */
284 for (j = 0; j < innerInputTokens->count; j++) {
285 if ((inputTokenTypes[j] & ITOK_TYPE_MASK) == smp->inputTokenType) {
287 /* Check for duplicate inner tokens */
288 major = GSS_S_DEFECTIVE_TOKEN;
289 *minor = GSSEAP_DUPLICATE_ITOK;
293 innerInputToken = &innerInputTokens->elements[j];
294 inputTokenType = &inputTokenTypes[j];
297 if (GSS_ERROR(major))
302 enum gss_eap_state oldState = ctx->state;
305 if (inputTokenType != NULL && (*inputTokenType & ITOK_FLAG_CRITICAL))
306 smFlags |= SM_FLAG_INPUT_TOKEN_CRITICAL;
308 major = smp->processToken(minor, cred, ctx, target, mech, reqFlags,
309 timeReq, chanBindings, innerInputToken,
310 &innerOutputToken, &smFlags);
311 if (GSS_ERROR(major))
314 if (inputTokenType != NULL)
315 *inputTokenType |= ITOK_FLAG_VERIFIED;
316 if (ctx->state < oldState)
318 else if (ctx->state != oldState)
319 smFlags |= SM_FLAG_TRANSITED;
321 if (innerOutputToken.value != NULL) {
322 innerOutputTokens->elements[innerOutputTokens->count] = innerOutputToken;
323 assert(smp->outputTokenType != ITOK_TYPE_NONE);
324 outputTokenTypes[innerOutputTokens->count] = smp->outputTokenType;
325 if (smFlags & SM_FLAG_OUTPUT_TOKEN_CRITICAL)
326 outputTokenTypes[innerOutputTokens->count] |= ITOK_FLAG_CRITICAL;
327 innerOutputTokens->count++;
330 * Break out if we made a state transition and have some tokens to send.
332 if ((smFlags & SM_FLAG_TRANSITED) &&
333 ((smFlags & SM_FLAG_FORCE_SEND_TOKEN) || innerOutputTokens->count != 0)) {
334 SM_ASSERT_VALID(ctx, major);
337 } else if ((smp->itokFlags & SM_ITOK_FLAG_REQUIRED) &&
338 smp->inputTokenType != ITOK_TYPE_NONE) {
339 /* Check for required inner tokens */
340 major = GSS_S_DEFECTIVE_TOKEN;
341 *minor = GSSEAP_MISSING_REQUIRED_ITOK;
346 assert(innerOutputTokens->count <= smCount);
348 /* Check we understood all critical tokens sent by peer */
349 if (!GSS_ERROR(major)) {
350 for (j = 0; j < innerInputTokens->count; j++) {
351 if ((inputTokenTypes[j] & ITOK_FLAG_CRITICAL) &&
352 (inputTokenTypes[j] & ITOK_FLAG_VERIFIED) == 0) {
353 major = GSS_S_UNAVAILABLE;
354 *minor = GSSEAP_CRIT_ITOK_UNAVAILABLE;
360 /* Optionaly emit an error token if we are the acceptor */
361 if (GSS_ERROR(major)) {
362 if (CTX_IS_INITIATOR(ctx))
363 goto cleanup; /* return error directly to caller */
365 /* replace any emitted tokens with error token */
366 gss_release_buffer_set(&tmpMinor, &innerOutputTokens);
368 tmpMajor = makeErrorToken(&tmpMinor, major, *minor, &innerOutputTokens);
369 if (GSS_ERROR(tmpMajor)) {
375 if (innerOutputTokens->count != 0)
376 outputTokenTypes[0] = ITOK_TYPE_CONTEXT_ERR | ITOK_FLAG_CRITICAL;
379 /* Format output token from inner tokens */
380 if (innerOutputTokens->count != 0 || /* inner tokens to send */
381 !CTX_IS_INITIATOR(ctx) || /* any leg acceptor */
382 !CTX_IS_ESTABLISHED(ctx)) { /* non-last leg initiator */
383 tmpMajor = gssEapEncodeInnerTokens(&tmpMinor, innerOutputTokens,
384 outputTokenTypes, &unwrappedOutputToken);
385 if (tmpMajor == GSS_S_COMPLETE) {
386 if (CTX_IS_INITIATOR(ctx))
387 tokType = TOK_TYPE_INITIATOR_CONTEXT;
389 tokType = TOK_TYPE_ACCEPTOR_CONTEXT;
391 tmpMajor = gssEapMakeToken(&tmpMinor, ctx, &unwrappedOutputToken,
392 tokType, outputToken);
393 if (GSS_ERROR(tmpMajor)) {
401 /* If the context is established, empty tokens only to be emitted by initiator */
402 assert(!CTX_IS_ESTABLISHED(ctx) || ((outputToken->length == 0) == CTX_IS_INITIATOR(ctx)));
404 SM_ASSERT_VALID(ctx, major);
407 gss_release_buffer_set(&tmpMinor, &innerInputTokens);
408 gss_release_buffer_set(&tmpMinor, &innerOutputTokens);
409 if (inputTokenTypes != NULL)
410 GSSEAP_FREE(inputTokenTypes);
411 if (outputTokenTypes != NULL)
412 gss_release_buffer(&tmpMinor, &unwrappedOutputToken);
413 GSSEAP_FREE(outputTokenTypes);