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_HMAC
23 *
24 * This function invokes the TPM2_HMAC 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] handle Handle for the symmetric signing key providing the HMAC
31 * key.
32 * @param[in] shandle1 Session handle for authorization of handle
33 * @param[in] shandle2 Second session handle.
34 * @param[in] shandle3 Third session handle.
35 * @param[in] buffer HMAC data.
36 * @param[in] hashAlg Algorithm to use for HMAC.
37 * @param[out] outHMAC The returned HMAC in a sized buffer.
38 * (callee-allocated)
39 * @retval TSS2_RC_SUCCESS if the function call was a success.
40 * @retval TSS2_ESYS_RC_BAD_REFERENCE if the esysContext or required input
41 * pointers or required output handle references are NULL.
42 * @retval TSS2_ESYS_RC_BAD_CONTEXT: if esysContext corruption is detected.
43 * @retval TSS2_ESYS_RC_MEMORY: if the ESAPI cannot allocate enough memory for
44 * internal operations or return parameters.
45 * @retval TSS2_ESYS_RC_BAD_SEQUENCE: if the context has an asynchronous
46 * operation already pending.
47 * @retval TSS2_ESYS_RC_INSUFFICIENT_RESPONSE: if the TPM's response does not
48 * at least contain the tag, response length, and response code.
49 * @retval TSS2_ESYS_RC_MALFORMED_RESPONSE: if the TPM's response is corrupted.
50 * @retval TSS2_ESYS_RC_RSP_AUTH_FAILED: if the response HMAC from the TPM
51 did not verify.
52 * @retval TSS2_ESYS_RC_MULTIPLE_DECRYPT_SESSIONS: if more than one session has
53 * the 'decrypt' attribute bit set.
54 * @retval TSS2_ESYS_RC_MULTIPLE_ENCRYPT_SESSIONS: if more than one session has
55 * the 'encrypt' attribute bit set.
56 * @retval TSS2_ESYS_RC_BAD_TR: if any of the ESYS_TR objects are unknown
57 * to the ESYS_CONTEXT or are of the wrong type or if required
58 * ESYS_TR objects are ESYS_TR_NONE.
59 * @retval TSS2_RCs produced by lower layers of the software stack may be
60 * returned to the caller unaltered unless handled internally.
61 */
62 TSS2_RC
Esys_HMAC(ESYS_CONTEXT * esysContext,ESYS_TR handle,ESYS_TR shandle1,ESYS_TR shandle2,ESYS_TR shandle3,const TPM2B_MAX_BUFFER * buffer,TPMI_ALG_HASH hashAlg,TPM2B_DIGEST ** outHMAC)63 Esys_HMAC(
64 ESYS_CONTEXT *esysContext,
65 ESYS_TR handle,
66 ESYS_TR shandle1,
67 ESYS_TR shandle2,
68 ESYS_TR shandle3,
69 const TPM2B_MAX_BUFFER *buffer,
70 TPMI_ALG_HASH hashAlg,
71 TPM2B_DIGEST **outHMAC)
72 {
73 TSS2_RC r;
74
75 r = Esys_HMAC_Async(esysContext, handle, shandle1, shandle2, shandle3,
76 buffer, hashAlg);
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_HMAC_Finish(esysContext, outHMAC);
91 /* This is just debug information about the reattempt to finish the
92 command */
93 if ((r & ~TSS2_RC_LAYER_MASK) == TSS2_BASE_RC_TRY_AGAIN)
94 LOG_DEBUG("A layer below returned TRY_AGAIN: %" PRIx32
95 " => resubmitting command", r);
96 } while ((r & ~TSS2_RC_LAYER_MASK) == 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_HMAC
106 *
107 * This function invokes the TPM2_HMAC 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_HMAC_Finish.
111 *
112 * @param[in,out] esysContext The ESYS_CONTEXT.
113 * @param[in] handle Handle for the symmetric signing key providing the HMAC
114 * key.
115 * @param[in] shandle1 Session handle for authorization of handle
116 * @param[in] shandle2 Second session handle.
117 * @param[in] shandle3 Third session handle.
118 * @param[in] buffer HMAC data.
119 * @param[in] hashAlg Algorithm to use for HMAC.
120 * @retval ESYS_RC_SUCCESS if the function call was a success.
121 * @retval TSS2_ESYS_RC_BAD_REFERENCE if the esysContext or required input
122 * pointers or required output handle references are NULL.
123 * @retval TSS2_ESYS_RC_BAD_CONTEXT: if esysContext corruption is detected.
124 * @retval TSS2_ESYS_RC_MEMORY: if the ESAPI cannot allocate enough memory for
125 * internal operations or return parameters.
126 * @retval TSS2_RCs produced by lower layers of the software stack may be
127 returned to the caller unaltered unless handled internally.
128 * @retval TSS2_ESYS_RC_MULTIPLE_DECRYPT_SESSIONS: if more than one session has
129 * the 'decrypt' attribute bit set.
130 * @retval TSS2_ESYS_RC_MULTIPLE_ENCRYPT_SESSIONS: if more than one session has
131 * the 'encrypt' attribute bit set.
132 * @retval TSS2_ESYS_RC_BAD_TR: if any of the ESYS_TR objects are unknown
133 * to the ESYS_CONTEXT or are of the wrong type or if required
134 * ESYS_TR objects are ESYS_TR_NONE.
135 */
136 TSS2_RC
Esys_HMAC_Async(ESYS_CONTEXT * esysContext,ESYS_TR handle,ESYS_TR shandle1,ESYS_TR shandle2,ESYS_TR shandle3,const TPM2B_MAX_BUFFER * buffer,TPMI_ALG_HASH hashAlg)137 Esys_HMAC_Async(
138 ESYS_CONTEXT *esysContext,
139 ESYS_TR handle,
140 ESYS_TR shandle1,
141 ESYS_TR shandle2,
142 ESYS_TR shandle3,
143 const TPM2B_MAX_BUFFER *buffer,
144 TPMI_ALG_HASH hashAlg)
145 {
146 TSS2_RC r;
147 LOG_TRACE("context=%p, handle=%"PRIx32 ", buffer=%p,"
148 "hashAlg=%04"PRIx16"",
149 esysContext, handle, buffer, hashAlg);
150 TSS2L_SYS_AUTH_COMMAND auths;
151 RSRC_NODE_T *handleNode;
152
153 /* Check context, sequence correctness and set state to error for now */
154 if (esysContext == NULL) {
155 LOG_ERROR("esyscontext is NULL.");
156 return TSS2_ESYS_RC_BAD_REFERENCE;
157 }
158 r = iesys_check_sequence_async(esysContext);
159 if (r != TSS2_RC_SUCCESS)
160 return r;
161 esysContext->state = _ESYS_STATE_INTERNALERROR;
162
163 /* Check input parameters */
164 r = check_session_feasibility(shandle1, shandle2, shandle3, 1);
165 return_state_if_error(r, _ESYS_STATE_INIT, "Check session usage");
166
167 /* Retrieve the metadata objects for provided handles */
168 r = esys_GetResourceObject(esysContext, handle, &handleNode);
169 return_state_if_error(r, _ESYS_STATE_INIT, "handle unknown.");
170
171 /* Initial invocation of SAPI to prepare the command buffer with parameters */
172 r = Tss2_Sys_HMAC_Prepare(esysContext->sys,
173 (handleNode == NULL) ? TPM2_RH_NULL
174 : handleNode->rsrc.handle, buffer, hashAlg);
175 return_state_if_error(r, _ESYS_STATE_INIT, "SAPI Prepare returned error.");
176
177 /* Calculate the cpHash Values */
178 r = init_session_tab(esysContext, shandle1, shandle2, shandle3);
179 return_state_if_error(r, _ESYS_STATE_INIT, "Initialize session resources");
180 if (handleNode != NULL)
181 iesys_compute_session_value(esysContext->session_tab[0],
182 &handleNode->rsrc.name, &handleNode->auth);
183 else
184 iesys_compute_session_value(esysContext->session_tab[0], NULL, NULL);
185
186 iesys_compute_session_value(esysContext->session_tab[1], NULL, NULL);
187 iesys_compute_session_value(esysContext->session_tab[2], NULL, NULL);
188
189 /* Generate the auth values and set them in the SAPI command buffer */
190 r = iesys_gen_auths(esysContext, handleNode, NULL, NULL, &auths);
191 return_state_if_error(r, _ESYS_STATE_INIT,
192 "Error in computation of auth values");
193
194 esysContext->authsCount = auths.count;
195 if (auths.count > 0) {
196 r = Tss2_Sys_SetCmdAuths(esysContext->sys, &auths);
197 return_state_if_error(r, _ESYS_STATE_INIT, "SAPI error on SetCmdAuths");
198 }
199
200 /* Trigger execution and finish the async invocation */
201 r = Tss2_Sys_ExecuteAsync(esysContext->sys);
202 return_state_if_error(r, _ESYS_STATE_INTERNALERROR,
203 "Finish (Execute Async)");
204
205 esysContext->state = _ESYS_STATE_SENT;
206
207 return r;
208 }
209
210 /** Asynchronous finish function for TPM2_HMAC
211 *
212 * This function returns the results of a TPM2_HMAC command
213 * invoked via Esys_HMAC_Finish. All non-simple output parameters
214 * are allocated by the function's implementation. NULL can be passed for every
215 * output parameter if the value is not required.
216 *
217 * @param[in,out] esysContext The ESYS_CONTEXT.
218 * @param[out] outHMAC The returned HMAC in a sized buffer.
219 * (callee-allocated)
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_HMAC_Finish(ESYS_CONTEXT * esysContext,TPM2B_DIGEST ** outHMAC)240 Esys_HMAC_Finish(
241 ESYS_CONTEXT *esysContext,
242 TPM2B_DIGEST **outHMAC)
243 {
244 TSS2_RC r;
245 LOG_TRACE("context=%p, outHMAC=%p",
246 esysContext, outHMAC);
247
248 if (esysContext == NULL) {
249 LOG_ERROR("esyscontext is NULL.");
250 return TSS2_ESYS_RC_BAD_REFERENCE;
251 }
252
253 /* Check for correct sequence and set sequence to irregular for now */
254 if (esysContext->state != _ESYS_STATE_SENT &&
255 esysContext->state != _ESYS_STATE_RESUBMISSION) {
256 LOG_ERROR("Esys called in bad sequence.");
257 return TSS2_ESYS_RC_BAD_SEQUENCE;
258 }
259 esysContext->state = _ESYS_STATE_INTERNALERROR;
260
261 /* Allocate memory for response parameters */
262 if (outHMAC != NULL) {
263 *outHMAC = calloc(sizeof(TPM2B_DIGEST), 1);
264 if (*outHMAC == NULL) {
265 return_error(TSS2_ESYS_RC_MEMORY, "Out of memory");
266 }
267 }
268
269 /*Receive the TPM response and handle resubmissions if necessary. */
270 r = Tss2_Sys_ExecuteFinish(esysContext->sys, esysContext->timeout);
271 if ((r & ~TSS2_RC_LAYER_MASK) == TSS2_BASE_RC_TRY_AGAIN) {
272 LOG_DEBUG("A layer below returned TRY_AGAIN: %" PRIx32, r);
273 esysContext->state = _ESYS_STATE_SENT;
274 goto error_cleanup;
275 }
276 /* This block handle the resubmission of TPM commands given a certain set of
277 * TPM response codes. */
278 if (r == TPM2_RC_RETRY || r == TPM2_RC_TESTING || r == TPM2_RC_YIELDED) {
279 LOG_DEBUG("TPM returned RETRY, TESTING or YIELDED, which triggers a "
280 "resubmission: %" PRIx32, r);
281 if (esysContext->submissionCount++ >= _ESYS_MAX_SUBMISSIONS) {
282 LOG_WARNING("Maximum number of (re)submissions has been reached.");
283 esysContext->state = _ESYS_STATE_INIT;
284 goto error_cleanup;
285 }
286 esysContext->state = _ESYS_STATE_RESUBMISSION;
287 r = Tss2_Sys_ExecuteAsync(esysContext->sys);
288 if (r != TSS2_RC_SUCCESS) {
289 LOG_WARNING("Error attempting to resubmit");
290 /* We do not set esysContext->state here but inherit the most recent
291 * state of the _async function. */
292 goto error_cleanup;
293 }
294 r = TSS2_ESYS_RC_TRY_AGAIN;
295 LOG_DEBUG("Resubmission initiated and returning RC_TRY_AGAIN.");
296 goto error_cleanup;
297 }
298 /* The following is the "regular error" handling. */
299 if (iesys_tpm_error(r)) {
300 LOG_WARNING("Received TPM Error");
301 esysContext->state = _ESYS_STATE_INIT;
302 goto error_cleanup;
303 } else if (r != TSS2_RC_SUCCESS) {
304 LOG_ERROR("Received a non-TPM Error");
305 esysContext->state = _ESYS_STATE_INTERNALERROR;
306 goto error_cleanup;
307 }
308
309 /*
310 * Now the verification of the response (hmac check) and if necessary the
311 * parameter decryption have to be done.
312 */
313 r = iesys_check_response(esysContext);
314 goto_state_if_error(r, _ESYS_STATE_INTERNALERROR, "Error: check response",
315 error_cleanup);
316
317 /*
318 * After the verification of the response we call the complete function
319 * to deliver the result.
320 */
321 r = Tss2_Sys_HMAC_Complete(esysContext->sys,
322 (outHMAC != NULL) ? *outHMAC : NULL);
323 goto_state_if_error(r, _ESYS_STATE_INTERNALERROR,
324 "Received error from SAPI unmarshaling" ,
325 error_cleanup);
326
327 esysContext->state = _ESYS_STATE_INIT;
328
329 return TSS2_RC_SUCCESS;
330
331 error_cleanup:
332 if (outHMAC != NULL)
333 SAFE_FREE(*outHMAC);
334
335 return r;
336 }
337