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 /** One-Call function for TPM2_PCR_Extend
23  *
24  * This function invokes the TPM2_PCR_Extend command in a one-call
25  * variant. This means the function will block until the TPM response is
26  * available. All input parameters are const. The memory for non-simple output
27  * parameters is allocated by the function implementation.
28  *
29  * @param[in,out] esysContext The ESYS_CONTEXT.
30  * @param[in]  pcrHandle Handle of the PCR.
31  * @param[in]  shandle1 Session handle for authorization of pcrHandle
32  * @param[in]  shandle2 Second session handle.
33  * @param[in]  shandle3 Third session handle.
34  * @param[in]  digests List of tagged digest values to be extended.
35  * @retval TSS2_RC_SUCCESS if the function call was a success.
36  * @retval TSS2_ESYS_RC_BAD_REFERENCE if the esysContext or required input
37  *         pointers or required output handle references are NULL.
38  * @retval TSS2_ESYS_RC_BAD_CONTEXT: if esysContext corruption is detected.
39  * @retval TSS2_ESYS_RC_MEMORY: if the ESAPI cannot allocate enough memory for
40  *         internal operations or return parameters.
41  * @retval TSS2_ESYS_RC_BAD_SEQUENCE: if the context has an asynchronous
42  *         operation already pending.
43  * @retval TSS2_ESYS_RC_INSUFFICIENT_RESPONSE: if the TPM's response does not
44  *          at least contain the tag, response length, and response code.
45  * @retval TSS2_ESYS_RC_MALFORMED_RESPONSE: if the TPM's response is corrupted.
46  * @retval TSS2_ESYS_RC_RSP_AUTH_FAILED: if the response HMAC from the TPM
47            did not verify.
48  * @retval TSS2_ESYS_RC_MULTIPLE_DECRYPT_SESSIONS: if more than one session has
49  *         the 'decrypt' attribute bit set.
50  * @retval TSS2_ESYS_RC_MULTIPLE_ENCRYPT_SESSIONS: if more than one session has
51  *         the 'encrypt' attribute bit set.
52  * @retval TSS2_ESYS_RC_BAD_TR: if any of the ESYS_TR objects are unknown
53  *         to the ESYS_CONTEXT or are of the wrong type or if required
54  *         ESYS_TR objects are ESYS_TR_NONE.
55  * @retval TSS2_ESYS_RC_NO_DECRYPT_PARAM: if one of the sessions has the
56  *         'decrypt' attribute set and the command does not support encryption
57  *         of the first command parameter.
58  * @retval TSS2_ESYS_RC_NO_ENCRYPT_PARAM: if one of the sessions has the
59  *         'encrypt' attribute set and the command does not support encryption
60  *          of the first response parameter.
61  * @retval TSS2_RCs produced by lower layers of the software stack may be
62  *         returned to the caller unaltered unless handled internally.
63  */
64 TSS2_RC
Esys_PCR_Extend(ESYS_CONTEXT * esysContext,ESYS_TR pcrHandle,ESYS_TR shandle1,ESYS_TR shandle2,ESYS_TR shandle3,const TPML_DIGEST_VALUES * digests)65 Esys_PCR_Extend(
66     ESYS_CONTEXT *esysContext,
67     ESYS_TR pcrHandle,
68     ESYS_TR shandle1,
69     ESYS_TR shandle2,
70     ESYS_TR shandle3,
71     const TPML_DIGEST_VALUES *digests)
72 {
73     TSS2_RC r;
74 
75     r = Esys_PCR_Extend_Async(esysContext, pcrHandle, shandle1, shandle2,
76                               shandle3, digests);
77     return_if_error(r, "Error in async function");
78 
79     /* Set the timeout to indefinite for now, since we want _Finish to block */
80     int32_t timeouttmp = esysContext->timeout;
81     esysContext->timeout = -1;
82     /*
83      * Now we call the finish function, until return code is not equal to
84      * from TSS2_BASE_RC_TRY_AGAIN.
85      * Note that the finish function may return TSS2_RC_TRY_AGAIN, even if we
86      * have set the timeout to -1. This occurs for example if the TPM requests
87      * a retransmission of the command via TPM2_RC_YIELDED.
88      */
89     do {
90         r = Esys_PCR_Extend_Finish(esysContext);
91         /* This is just debug information about the reattempt to finish the
92            command */
93         if (base_rc(r) == TSS2_BASE_RC_TRY_AGAIN)
94             LOG_DEBUG("A layer below returned TRY_AGAIN: %" PRIx32
95                       " => resubmitting command", r);
96     } while (base_rc(r) == TSS2_BASE_RC_TRY_AGAIN);
97 
98     /* Restore the timeout value to the original value */
99     esysContext->timeout = timeouttmp;
100     return_if_error(r, "Esys Finish");
101 
102     return TSS2_RC_SUCCESS;
103 }
104 
105 /** Asynchronous function for TPM2_PCR_Extend
106  *
107  * This function invokes the TPM2_PCR_Extend command in a asynchronous
108  * variant. This means the function will return as soon as the command has been
109  * sent downwards the stack to the TPM. All input parameters are const.
110  * In order to retrieve the TPM's response call Esys_PCR_Extend_Finish.
111  *
112  * @param[in,out] esysContext The ESYS_CONTEXT.
113  * @param[in]  pcrHandle Handle of the PCR.
114  * @param[in]  shandle1 Session handle for authorization of pcrHandle
115  * @param[in]  shandle2 Second session handle.
116  * @param[in]  shandle3 Third session handle.
117  * @param[in]  digests List of tagged digest values to be extended.
118  * @retval ESYS_RC_SUCCESS if the function call was a success.
119  * @retval TSS2_ESYS_RC_BAD_REFERENCE if the esysContext or required input
120  *         pointers or required output handle references are NULL.
121  * @retval TSS2_ESYS_RC_BAD_CONTEXT: if esysContext corruption is detected.
122  * @retval TSS2_ESYS_RC_MEMORY: if the ESAPI cannot allocate enough memory for
123  *         internal operations or return parameters.
124  * @retval TSS2_RCs produced by lower layers of the software stack may be
125            returned to the caller unaltered unless handled internally.
126  * @retval TSS2_ESYS_RC_MULTIPLE_DECRYPT_SESSIONS: if more than one session has
127  *         the 'decrypt' attribute bit set.
128  * @retval TSS2_ESYS_RC_MULTIPLE_ENCRYPT_SESSIONS: if more than one session has
129  *         the 'encrypt' attribute bit set.
130  * @retval TSS2_ESYS_RC_BAD_TR: if any of the ESYS_TR objects are unknown
131  *         to the ESYS_CONTEXT or are of the wrong type or if required
132  *         ESYS_TR objects are ESYS_TR_NONE.
133  * @retval TSS2_ESYS_RC_NO_DECRYPT_PARAM: if one of the sessions has the
134  *         'decrypt' attribute set and the command does not support encryption
135  *         of the first command parameter.
136  * @retval TSS2_ESYS_RC_NO_ENCRYPT_PARAM: if one of the sessions has the
137  *         'encrypt' attribute set and the command does not support encryption
138  *          of the first response parameter.
139  */
140 TSS2_RC
Esys_PCR_Extend_Async(ESYS_CONTEXT * esysContext,ESYS_TR pcrHandle,ESYS_TR shandle1,ESYS_TR shandle2,ESYS_TR shandle3,const TPML_DIGEST_VALUES * digests)141 Esys_PCR_Extend_Async(
142     ESYS_CONTEXT *esysContext,
143     ESYS_TR pcrHandle,
144     ESYS_TR shandle1,
145     ESYS_TR shandle2,
146     ESYS_TR shandle3,
147     const TPML_DIGEST_VALUES *digests)
148 {
149     TSS2_RC r;
150     LOG_TRACE("context=%p, pcrHandle=%"PRIx32 ", digests=%p",
151               esysContext, pcrHandle, digests);
152     TSS2L_SYS_AUTH_COMMAND auths;
153     RSRC_NODE_T *pcrHandleNode;
154 
155     /* Check context, sequence correctness and set state to error for now */
156     if (esysContext == NULL) {
157         LOG_ERROR("esyscontext is NULL.");
158         return TSS2_ESYS_RC_BAD_REFERENCE;
159     }
160     r = iesys_check_sequence_async(esysContext);
161     if (r != TSS2_RC_SUCCESS)
162         return r;
163     esysContext->state = _ESYS_STATE_INTERNALERROR;
164 
165     /* Check input parameters */
166     r = check_session_feasibility(shandle1, shandle2, shandle3, 1);
167     return_state_if_error(r, _ESYS_STATE_INIT, "Check session usage");
168 
169     /* Retrieve the metadata objects for provided handles */
170     r = esys_GetResourceObject(esysContext, pcrHandle, &pcrHandleNode);
171     return_state_if_error(r, _ESYS_STATE_INIT, "pcrHandle unknown.");
172 
173     /* Initial invocation of SAPI to prepare the command buffer with parameters */
174     r = Tss2_Sys_PCR_Extend_Prepare(esysContext->sys,
175                                     (pcrHandleNode == NULL) ? TPM2_RH_NULL
176                                      : pcrHandleNode->rsrc.handle, digests);
177     return_state_if_error(r, _ESYS_STATE_INIT, "SAPI Prepare returned error.");
178 
179     /* Calculate the cpHash Values */
180     r = init_session_tab(esysContext, shandle1, shandle2, shandle3);
181     return_state_if_error(r, _ESYS_STATE_INIT, "Initialize session resources");
182     if (pcrHandleNode != NULL)
183         iesys_compute_session_value(esysContext->session_tab[0],
184                 &pcrHandleNode->rsrc.name, &pcrHandleNode->auth);
185     else
186         iesys_compute_session_value(esysContext->session_tab[0], NULL, NULL);
187 
188     iesys_compute_session_value(esysContext->session_tab[1], NULL, NULL);
189     iesys_compute_session_value(esysContext->session_tab[2], NULL, NULL);
190 
191     /* Generate the auth values and set them in the SAPI command buffer */
192     r = iesys_gen_auths(esysContext, pcrHandleNode, NULL, NULL, &auths);
193     return_state_if_error(r, _ESYS_STATE_INIT,
194                           "Error in computation of auth values");
195 
196     esysContext->authsCount = auths.count;
197     if (auths.count > 0) {
198         r = Tss2_Sys_SetCmdAuths(esysContext->sys, &auths);
199         return_state_if_error(r, _ESYS_STATE_INIT, "SAPI error on SetCmdAuths");
200     }
201 
202     /* Trigger execution and finish the async invocation */
203     r = Tss2_Sys_ExecuteAsync(esysContext->sys);
204     return_state_if_error(r, _ESYS_STATE_INTERNALERROR,
205                           "Finish (Execute Async)");
206 
207     esysContext->state = _ESYS_STATE_SENT;
208 
209     return r;
210 }
211 
212 /** Asynchronous finish function for TPM2_PCR_Extend
213  *
214  * This function returns the results of a TPM2_PCR_Extend command
215  * invoked via Esys_PCR_Extend_Finish. All non-simple output parameters
216  * are allocated by the function's implementation. NULL can be passed for every
217  * output parameter if the value is not required.
218  *
219  * @param[in,out] esysContext The ESYS_CONTEXT.
220  * @retval TSS2_RC_SUCCESS on success
221  * @retval ESYS_RC_SUCCESS if the function call was a success.
222  * @retval TSS2_ESYS_RC_BAD_REFERENCE if the esysContext or required input
223  *         pointers or required output handle references are NULL.
224  * @retval TSS2_ESYS_RC_BAD_CONTEXT: if esysContext corruption is detected.
225  * @retval TSS2_ESYS_RC_MEMORY: if the ESAPI cannot allocate enough memory for
226  *         internal operations or return parameters.
227  * @retval TSS2_ESYS_RC_BAD_SEQUENCE: if the context has an asynchronous
228  *         operation already pending.
229  * @retval TSS2_ESYS_RC_TRY_AGAIN: if the timeout counter expires before the
230  *         TPM response is received.
231  * @retval TSS2_ESYS_RC_INSUFFICIENT_RESPONSE: if the TPM's response does not
232  *         at least contain the tag, response length, and response code.
233  * @retval TSS2_ESYS_RC_RSP_AUTH_FAILED: if the response HMAC from the TPM did
234  *         not verify.
235  * @retval TSS2_ESYS_RC_MALFORMED_RESPONSE: if the TPM's response is corrupted.
236  * @retval TSS2_RCs produced by lower layers of the software stack may be
237  *         returned to the caller unaltered unless handled internally.
238  */
239 TSS2_RC
Esys_PCR_Extend_Finish(ESYS_CONTEXT * esysContext)240 Esys_PCR_Extend_Finish(
241     ESYS_CONTEXT *esysContext)
242 {
243     TSS2_RC r;
244     LOG_TRACE("context=%p",
245               esysContext);
246 
247     if (esysContext == NULL) {
248         LOG_ERROR("esyscontext is NULL.");
249         return TSS2_ESYS_RC_BAD_REFERENCE;
250     }
251 
252     /* Check for correct sequence and set sequence to irregular for now */
253     if (esysContext->state != _ESYS_STATE_SENT &&
254         esysContext->state != _ESYS_STATE_RESUBMISSION) {
255         LOG_ERROR("Esys called in bad sequence.");
256         return TSS2_ESYS_RC_BAD_SEQUENCE;
257     }
258     esysContext->state = _ESYS_STATE_INTERNALERROR;
259 
260     /*Receive the TPM response and handle resubmissions if necessary. */
261     r = Tss2_Sys_ExecuteFinish(esysContext->sys, esysContext->timeout);
262     if (base_rc(r) == TSS2_BASE_RC_TRY_AGAIN) {
263         LOG_DEBUG("A layer below returned TRY_AGAIN: %" PRIx32, r);
264         esysContext->state = _ESYS_STATE_SENT;
265         return r;
266     }
267     /* This block handle the resubmission of TPM commands given a certain set of
268      * TPM response codes. */
269     if (r == TPM2_RC_RETRY || r == TPM2_RC_TESTING || r == TPM2_RC_YIELDED) {
270         LOG_DEBUG("TPM returned RETRY, TESTING or YIELDED, which triggers a "
271             "resubmission: %" PRIx32, r);
272         if (esysContext->submissionCount++ >= _ESYS_MAX_SUBMISSIONS) {
273             LOG_WARNING("Maximum number of (re)submissions has been reached.");
274             esysContext->state = _ESYS_STATE_INIT;
275             return r;
276         }
277         esysContext->state = _ESYS_STATE_RESUBMISSION;
278         r = Tss2_Sys_ExecuteAsync(esysContext->sys);
279         if (r != TSS2_RC_SUCCESS) {
280             LOG_WARNING("Error attempting to resubmit");
281             /* We do not set esysContext->state here but inherit the most recent
282              * state of the _async function. */
283             return r;
284         }
285         r = TSS2_ESYS_RC_TRY_AGAIN;
286         LOG_DEBUG("Resubmission initiated and returning RC_TRY_AGAIN.");
287         return r;
288     }
289     /* The following is the "regular error" handling. */
290     if (iesys_tpm_error(r)) {
291         LOG_WARNING("Received TPM Error");
292         esysContext->state = _ESYS_STATE_INIT;
293         return r;
294     } else if (r != TSS2_RC_SUCCESS) {
295         LOG_ERROR("Received a non-TPM Error");
296         esysContext->state = _ESYS_STATE_INTERNALERROR;
297         return r;
298     }
299 
300     /*
301      * Now the verification of the response (hmac check) and if necessary the
302      * parameter decryption have to be done.
303      */
304     r = iesys_check_response(esysContext);
305     return_state_if_error(r, _ESYS_STATE_INTERNALERROR,
306                           "Error: check response");
307 
308     /*
309      * After the verification of the response we call the complete function
310      * to deliver the result.
311      */
312     r = Tss2_Sys_PCR_Extend_Complete(esysContext->sys);
313     return_state_if_error(r, _ESYS_STATE_INTERNALERROR,
314                           "Received error from SAPI unmarshaling" );
315 
316     esysContext->state = _ESYS_STATE_INIT;
317 
318     return TSS2_RC_SUCCESS;
319 }
320