1 /* SPDX-License-Identifier: BSD-2-Clause */
2 /*******************************************************************************
3  * Copyright 2017-2018, Fraunhofer SIT sponsored by Infineon Technologies AG
4  * All rights reserved.
5  ******************************************************************************/
6 
7 #ifdef HAVE_CONFIG_H
8 #include <config.h>
9 #endif
10 
11 #include "tss2_mu.h"
12 #include "tss2_sys.h"
13 #include "tss2_esys.h"
14 
15 #include "esys_types.h"
16 #include "esys_iutil.h"
17 #include "esys_mu.h"
18 #define LOGMODULE esys
19 #include "util/log.h"
20 #include "util/aux_util.h"
21 
22 /** Store command parameters inside the ESYS_CONTEXT for use during _Finish */
store_input_parameters(ESYS_CONTEXT * esysContext,ESYS_TR sequenceHandle)23 static void store_input_parameters (
24     ESYS_CONTEXT *esysContext,
25     ESYS_TR sequenceHandle)
26 {
27     esysContext->in.SequenceComplete.sequenceHandle = sequenceHandle;
28 }
29 
30 /** One-Call function for TPM2_SequenceComplete
31  *
32  * This function invokes the TPM2_SequenceComplete command in a one-call
33  * variant. This means the function will block until the TPM response is
34  * available. All input parameters are const. The memory for non-simple output
35  * parameters is allocated by the function implementation.
36  *
37  * @param[in,out] esysContext The ESYS_CONTEXT.
38  * @param[in]  sequenceHandle Authorization for the sequence.
39  * @param[in]  shandle1 Session handle for authorization of sequenceHandle
40  * @param[in]  shandle2 Second session handle.
41  * @param[in]  shandle3 Third session handle.
42  * @param[in]  buffer Data to be added to the hash/HMAC.
43  * @param[in]  hierarchy Hierarchy of the ticket for a hash.
44  * @param[out] result The returned HMAC or digest in a sized buffer.
45  *             (callee-allocated)
46  * @param[out] validation TPM2_Ticket indicating that the sequence of octets used to
47  *             compute outDigest did not start with TPM2_GENERATED_VALUE.
48  *             (callee-allocated)
49  * @retval TSS2_RC_SUCCESS if the function call was a success.
50  * @retval TSS2_ESYS_RC_BAD_REFERENCE if the esysContext or required input
51  *         pointers or required output handle references are NULL.
52  * @retval TSS2_ESYS_RC_BAD_CONTEXT: if esysContext corruption is detected.
53  * @retval TSS2_ESYS_RC_MEMORY: if the ESAPI cannot allocate enough memory for
54  *         internal operations or return parameters.
55  * @retval TSS2_ESYS_RC_BAD_SEQUENCE: if the context has an asynchronous
56  *         operation already pending.
57  * @retval TSS2_ESYS_RC_INSUFFICIENT_RESPONSE: if the TPM's response does not
58  *          at least contain the tag, response length, and response code.
59  * @retval TSS2_ESYS_RC_MALFORMED_RESPONSE: if the TPM's response is corrupted.
60  * @retval TSS2_ESYS_RC_RSP_AUTH_FAILED: if the response HMAC from the TPM
61            did not verify.
62  * @retval TSS2_ESYS_RC_MULTIPLE_DECRYPT_SESSIONS: if more than one session has
63  *         the 'decrypt' attribute bit set.
64  * @retval TSS2_ESYS_RC_MULTIPLE_ENCRYPT_SESSIONS: if more than one session has
65  *         the 'encrypt' attribute bit set.
66  * @retval TSS2_ESYS_RC_BAD_TR: if any of the ESYS_TR objects are unknown
67  *         to the ESYS_CONTEXT or are of the wrong type or if required
68  *         ESYS_TR objects are ESYS_TR_NONE.
69  * @retval TSS2_RCs produced by lower layers of the software stack may be
70  *         returned to the caller unaltered unless handled internally.
71  */
72 TSS2_RC
Esys_SequenceComplete(ESYS_CONTEXT * esysContext,ESYS_TR sequenceHandle,ESYS_TR shandle1,ESYS_TR shandle2,ESYS_TR shandle3,const TPM2B_MAX_BUFFER * buffer,ESYS_TR hierarchy,TPM2B_DIGEST ** result,TPMT_TK_HASHCHECK ** validation)73 Esys_SequenceComplete(
74     ESYS_CONTEXT *esysContext,
75     ESYS_TR sequenceHandle,
76     ESYS_TR shandle1,
77     ESYS_TR shandle2,
78     ESYS_TR shandle3,
79     const TPM2B_MAX_BUFFER *buffer,
80     ESYS_TR hierarchy,
81     TPM2B_DIGEST **result,
82     TPMT_TK_HASHCHECK **validation)
83 {
84     TSS2_RC r;
85 
86     r = Esys_SequenceComplete_Async(esysContext, sequenceHandle, shandle1,
87                                     shandle2, shandle3, buffer, hierarchy);
88     return_if_error(r, "Error in async function");
89 
90     /* Set the timeout to indefinite for now, since we want _Finish to block */
91     int32_t timeouttmp = esysContext->timeout;
92     esysContext->timeout = -1;
93     /*
94      * Now we call the finish function, until return code is not equal to
95      * from TSS2_BASE_RC_TRY_AGAIN.
96      * Note that the finish function may return TSS2_RC_TRY_AGAIN, even if we
97      * have set the timeout to -1. This occurs for example if the TPM requests
98      * a retransmission of the command via TPM2_RC_YIELDED.
99      */
100     do {
101         r = Esys_SequenceComplete_Finish(esysContext, result, validation);
102         /* This is just debug information about the reattempt to finish the
103            command */
104         if (base_rc(r) == TSS2_BASE_RC_TRY_AGAIN)
105             LOG_DEBUG("A layer below returned TRY_AGAIN: %" PRIx32
106                       " => resubmitting command", r);
107     } while (base_rc(r) == TSS2_BASE_RC_TRY_AGAIN);
108 
109     /* Restore the timeout value to the original value */
110     esysContext->timeout = timeouttmp;
111     return_if_error(r, "Esys Finish");
112 
113     return TSS2_RC_SUCCESS;
114 }
115 
116 /** Asynchronous function for TPM2_SequenceComplete
117  *
118  * This function invokes the TPM2_SequenceComplete command in a asynchronous
119  * variant. This means the function will return as soon as the command has been
120  * sent downwards the stack to the TPM. All input parameters are const.
121  * In order to retrieve the TPM's response call Esys_SequenceComplete_Finish.
122  *
123  * @param[in,out] esysContext The ESYS_CONTEXT.
124  * @param[in]  sequenceHandle Authorization for the sequence.
125  * @param[in]  shandle1 Session handle for authorization of sequenceHandle
126  * @param[in]  shandle2 Second session handle.
127  * @param[in]  shandle3 Third session handle.
128  * @param[in]  buffer Data to be added to the hash/HMAC.
129  * @param[in]  hierarchy Hierarchy of the ticket for a hash.
130  * @retval ESYS_RC_SUCCESS if the function call was a success.
131  * @retval TSS2_ESYS_RC_BAD_REFERENCE if the esysContext or required input
132  *         pointers or required output handle references are NULL.
133  * @retval TSS2_ESYS_RC_BAD_CONTEXT: if esysContext corruption is detected.
134  * @retval TSS2_ESYS_RC_MEMORY: if the ESAPI cannot allocate enough memory for
135  *         internal operations or return parameters.
136  * @retval TSS2_RCs produced by lower layers of the software stack may be
137            returned to the caller unaltered unless handled internally.
138  * @retval TSS2_ESYS_RC_MULTIPLE_DECRYPT_SESSIONS: if more than one session has
139  *         the 'decrypt' attribute bit set.
140  * @retval TSS2_ESYS_RC_MULTIPLE_ENCRYPT_SESSIONS: if more than one session has
141  *         the 'encrypt' attribute bit set.
142  * @retval TSS2_ESYS_RC_BAD_TR: if any of the ESYS_TR objects are unknown
143  *         to the ESYS_CONTEXT or are of the wrong type or if required
144  *         ESYS_TR objects are ESYS_TR_NONE.
145  */
146 TSS2_RC
Esys_SequenceComplete_Async(ESYS_CONTEXT * esysContext,ESYS_TR sequenceHandle,ESYS_TR shandle1,ESYS_TR shandle2,ESYS_TR shandle3,const TPM2B_MAX_BUFFER * buffer,ESYS_TR hierarchy)147 Esys_SequenceComplete_Async(
148     ESYS_CONTEXT *esysContext,
149     ESYS_TR sequenceHandle,
150     ESYS_TR shandle1,
151     ESYS_TR shandle2,
152     ESYS_TR shandle3,
153     const TPM2B_MAX_BUFFER *buffer,
154     ESYS_TR hierarchy)
155 {
156     TSS2_RC r;
157     LOG_TRACE("context=%p, sequenceHandle=%"PRIx32 ", buffer=%p,"
158               "hierarchy=%"PRIx32 "",
159               esysContext, sequenceHandle, buffer, hierarchy);
160     TSS2L_SYS_AUTH_COMMAND auths;
161     RSRC_NODE_T *sequenceHandleNode;
162     TPMI_RH_HIERARCHY tpm_hierarchy;
163 
164     /* Check context, sequence correctness and set state to error for now */
165     if (esysContext == NULL) {
166         LOG_ERROR("esyscontext is NULL.");
167         return TSS2_ESYS_RC_BAD_REFERENCE;
168     }
169 
170     r = iesys_handle_to_tpm_handle(hierarchy, &tpm_hierarchy);
171     if (r != TSS2_RC_SUCCESS) {
172         if (!iesys_is_platform_handle(hierarchy)) {
173             return r;
174         }
175         tpm_hierarchy = hierarchy;
176     }
177 
178     r = iesys_check_sequence_async(esysContext);
179     if (r != TSS2_RC_SUCCESS)
180         return r;
181     esysContext->state = _ESYS_STATE_INTERNALERROR;
182 
183     /* Check input parameters */
184     r = check_session_feasibility(shandle1, shandle2, shandle3, 1);
185     return_state_if_error(r, _ESYS_STATE_INIT, "Check session usage");
186     store_input_parameters(esysContext, sequenceHandle);
187 
188     /* Retrieve the metadata objects for provided handles */
189     r = esys_GetResourceObject(esysContext, sequenceHandle, &sequenceHandleNode);
190     return_state_if_error(r, _ESYS_STATE_INIT, "sequenceHandle unknown.");
191 
192     /* Initial invocation of SAPI to prepare the command buffer with parameters */
193     r = Tss2_Sys_SequenceComplete_Prepare(esysContext->sys,
194                                           (sequenceHandleNode == NULL)
195                                            ? TPM2_RH_NULL
196                                            : sequenceHandleNode->rsrc.handle,
197                                           buffer, tpm_hierarchy);
198     return_state_if_error(r, _ESYS_STATE_INIT, "SAPI Prepare returned error.");
199 
200     /* Calculate the cpHash Values */
201     r = init_session_tab(esysContext, shandle1, shandle2, shandle3);
202     return_state_if_error(r, _ESYS_STATE_INIT, "Initialize session resources");
203     if (sequenceHandleNode != NULL)
204         iesys_compute_session_value(esysContext->session_tab[0],
205                 &sequenceHandleNode->rsrc.name, &sequenceHandleNode->auth);
206     else
207         iesys_compute_session_value(esysContext->session_tab[0], NULL, NULL);
208 
209     iesys_compute_session_value(esysContext->session_tab[1], NULL, NULL);
210     iesys_compute_session_value(esysContext->session_tab[2], NULL, NULL);
211 
212     /* Generate the auth values and set them in the SAPI command buffer */
213     r = iesys_gen_auths(esysContext, sequenceHandleNode, NULL, NULL, &auths);
214     return_state_if_error(r, _ESYS_STATE_INIT,
215                           "Error in computation of auth values");
216 
217     esysContext->authsCount = auths.count;
218     if (auths.count > 0) {
219         r = Tss2_Sys_SetCmdAuths(esysContext->sys, &auths);
220         return_state_if_error(r, _ESYS_STATE_INIT, "SAPI error on SetCmdAuths");
221     }
222 
223     /* Trigger execution and finish the async invocation */
224     r = Tss2_Sys_ExecuteAsync(esysContext->sys);
225     return_state_if_error(r, _ESYS_STATE_INTERNALERROR,
226                           "Finish (Execute Async)");
227 
228     esysContext->state = _ESYS_STATE_SENT;
229 
230     return r;
231 }
232 
233 /** Asynchronous finish function for TPM2_SequenceComplete
234  *
235  * This function returns the results of a TPM2_SequenceComplete command
236  * invoked via Esys_SequenceComplete_Finish. All non-simple output parameters
237  * are allocated by the function's implementation. NULL can be passed for every
238  * output parameter if the value is not required.
239  *
240  * @param[in,out] esysContext The ESYS_CONTEXT.
241  * @param[out] result The returned HMAC or digest in a sized buffer.
242  *             (callee-allocated)
243  * @param[out] validation TPM2_Ticket indicating that the sequence of octets used to
244  *             compute outDigest did not start with TPM2_GENERATED_VALUE.
245  *             (callee-allocated)
246  * @retval TSS2_RC_SUCCESS on success
247  * @retval ESYS_RC_SUCCESS if the function call was a success.
248  * @retval TSS2_ESYS_RC_BAD_REFERENCE if the esysContext or required input
249  *         pointers or required output handle references are NULL.
250  * @retval TSS2_ESYS_RC_BAD_CONTEXT: if esysContext corruption is detected.
251  * @retval TSS2_ESYS_RC_MEMORY: if the ESAPI cannot allocate enough memory for
252  *         internal operations or return parameters.
253  * @retval TSS2_ESYS_RC_BAD_SEQUENCE: if the context has an asynchronous
254  *         operation already pending.
255  * @retval TSS2_ESYS_RC_TRY_AGAIN: if the timeout counter expires before the
256  *         TPM response is received.
257  * @retval TSS2_ESYS_RC_INSUFFICIENT_RESPONSE: if the TPM's response does not
258  *         at least contain the tag, response length, and response code.
259  * @retval TSS2_ESYS_RC_RSP_AUTH_FAILED: if the response HMAC from the TPM did
260  *         not verify.
261  * @retval TSS2_ESYS_RC_MALFORMED_RESPONSE: if the TPM's response is corrupted.
262  * @retval TSS2_RCs produced by lower layers of the software stack may be
263  *         returned to the caller unaltered unless handled internally.
264  */
265 TSS2_RC
Esys_SequenceComplete_Finish(ESYS_CONTEXT * esysContext,TPM2B_DIGEST ** result,TPMT_TK_HASHCHECK ** validation)266 Esys_SequenceComplete_Finish(
267     ESYS_CONTEXT *esysContext,
268     TPM2B_DIGEST **result,
269     TPMT_TK_HASHCHECK **validation)
270 {
271     TSS2_RC r;
272     LOG_TRACE("context=%p, result=%p, validation=%p",
273               esysContext, result, validation);
274 
275     if (esysContext == NULL) {
276         LOG_ERROR("esyscontext is NULL.");
277         return TSS2_ESYS_RC_BAD_REFERENCE;
278     }
279 
280     /* Check for correct sequence and set sequence to irregular for now */
281     if (esysContext->state != _ESYS_STATE_SENT &&
282         esysContext->state != _ESYS_STATE_RESUBMISSION) {
283         LOG_ERROR("Esys called in bad sequence.");
284         return TSS2_ESYS_RC_BAD_SEQUENCE;
285     }
286     esysContext->state = _ESYS_STATE_INTERNALERROR;
287 
288     /* Allocate memory for response parameters */
289     if (result != NULL) {
290         *result = calloc(sizeof(TPM2B_DIGEST), 1);
291         if (*result == NULL) {
292             return_error(TSS2_ESYS_RC_MEMORY, "Out of memory");
293         }
294     }
295     if (validation != NULL) {
296         *validation = calloc(sizeof(TPMT_TK_HASHCHECK), 1);
297         if (*validation == NULL) {
298             goto_error(r, TSS2_ESYS_RC_MEMORY, "Out of memory", error_cleanup);
299         }
300     }
301 
302     /*Receive the TPM response and handle resubmissions if necessary. */
303     r = Tss2_Sys_ExecuteFinish(esysContext->sys, esysContext->timeout);
304     if (base_rc(r) == TSS2_BASE_RC_TRY_AGAIN) {
305         LOG_DEBUG("A layer below returned TRY_AGAIN: %" PRIx32, r);
306         esysContext->state = _ESYS_STATE_SENT;
307         goto error_cleanup;
308     }
309     /* This block handle the resubmission of TPM commands given a certain set of
310      * TPM response codes. */
311     if (r == TPM2_RC_RETRY || r == TPM2_RC_TESTING || r == TPM2_RC_YIELDED) {
312         LOG_DEBUG("TPM returned RETRY, TESTING or YIELDED, which triggers a "
313             "resubmission: %" PRIx32, r);
314         if (esysContext->submissionCount++ >= _ESYS_MAX_SUBMISSIONS) {
315             LOG_WARNING("Maximum number of (re)submissions has been reached.");
316             esysContext->state = _ESYS_STATE_INIT;
317             goto error_cleanup;
318         }
319         esysContext->state = _ESYS_STATE_RESUBMISSION;
320         r = Tss2_Sys_ExecuteAsync(esysContext->sys);
321         if (r != TSS2_RC_SUCCESS) {
322             LOG_WARNING("Error attempting to resubmit");
323             /* We do not set esysContext->state here but inherit the most recent
324              * state of the _async function. */
325             goto error_cleanup;
326         }
327         r = TSS2_ESYS_RC_TRY_AGAIN;
328         LOG_DEBUG("Resubmission initiated and returning RC_TRY_AGAIN.");
329         goto error_cleanup;
330     }
331     /* The following is the "regular error" handling. */
332     if (iesys_tpm_error(r)) {
333         LOG_WARNING("Received TPM Error");
334         esysContext->state = _ESYS_STATE_INIT;
335         goto error_cleanup;
336     } else if (r != TSS2_RC_SUCCESS) {
337         LOG_ERROR("Received a non-TPM Error");
338         esysContext->state = _ESYS_STATE_INTERNALERROR;
339         goto error_cleanup;
340     }
341 
342     /*
343      * Now the verification of the response (hmac check) and if necessary the
344      * parameter decryption have to be done.
345      */
346     r = iesys_check_response(esysContext);
347     goto_state_if_error(r, _ESYS_STATE_INTERNALERROR, "Error: check response",
348                         error_cleanup);
349 
350     /*
351      * After the verification of the response we call the complete function
352      * to deliver the result.
353      */
354     r = Tss2_Sys_SequenceComplete_Complete(esysContext->sys,
355                                            (result != NULL) ? *result : NULL,
356                                            (validation != NULL) ? *validation
357                                             : NULL);
358     goto_state_if_error(r, _ESYS_STATE_INTERNALERROR,
359                         "Received error from SAPI unmarshaling" ,
360                         error_cleanup);
361 
362     /* The ESYS_TR sequence object has to be invalidated */
363     r = Esys_TR_Close(esysContext,
364                       &esysContext->in.SequenceComplete.sequenceHandle);
365     goto_if_error(r, "invalidate object", error_cleanup);
366 
367     esysContext->state = _ESYS_STATE_INIT;
368 
369     return TSS2_RC_SUCCESS;
370 
371 error_cleanup:
372     if (result != NULL)
373         SAFE_FREE(*result);
374     if (validation != NULL)
375         SAFE_FREE(*validation);
376 
377     return r;
378 }
379