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_EC_Ephemeral
23 *
24 * This function invokes the TPM2_EC_Ephemeral 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] shandle1 First session handle.
31 * @param[in] shandle2 Second session handle.
32 * @param[in] shandle3 Third session handle.
33 * @param[in] curveID The curve for the computed ephemeral point .
34 * @param[out] Q Ephemeral public key Q := [r]G.
35 * (callee-allocated)
36 * @param[out] counter Least-significant 16 bits of commitCount.
37 * (callee-allocated)
38 * @retval TSS2_RC_SUCCESS if the function call was a success.
39 * @retval TSS2_ESYS_RC_BAD_REFERENCE if the esysContext or required input
40 * pointers or required output handle references are NULL.
41 * @retval TSS2_ESYS_RC_BAD_CONTEXT: if esysContext corruption is detected.
42 * @retval TSS2_ESYS_RC_MEMORY: if the ESAPI cannot allocate enough memory for
43 * internal operations or return parameters.
44 * @retval TSS2_ESYS_RC_BAD_SEQUENCE: if the context has an asynchronous
45 * operation already pending.
46 * @retval TSS2_ESYS_RC_INSUFFICIENT_RESPONSE: if the TPM's response does not
47 * at least contain the tag, response length, and response code.
48 * @retval TSS2_ESYS_RC_MALFORMED_RESPONSE: if the TPM's response is corrupted.
49 * @retval TSS2_ESYS_RC_RSP_AUTH_FAILED: if the response HMAC from the TPM
50 did not verify.
51 * @retval TSS2_ESYS_RC_MULTIPLE_DECRYPT_SESSIONS: if more than one session has
52 * the 'decrypt' attribute bit set.
53 * @retval TSS2_ESYS_RC_MULTIPLE_ENCRYPT_SESSIONS: if more than one session has
54 * the 'encrypt' attribute bit set.
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_RCs produced by lower layers of the software stack may be
59 * returned to the caller unaltered unless handled internally.
60 */
61 TSS2_RC
Esys_EC_Ephemeral(ESYS_CONTEXT * esysContext,ESYS_TR shandle1,ESYS_TR shandle2,ESYS_TR shandle3,TPMI_ECC_CURVE curveID,TPM2B_ECC_POINT ** Q,UINT16 * counter)62 Esys_EC_Ephemeral(
63 ESYS_CONTEXT *esysContext,
64 ESYS_TR shandle1,
65 ESYS_TR shandle2,
66 ESYS_TR shandle3,
67 TPMI_ECC_CURVE curveID,
68 TPM2B_ECC_POINT **Q,
69 UINT16 *counter)
70 {
71 TSS2_RC r;
72
73 r = Esys_EC_Ephemeral_Async(esysContext, shandle1, shandle2, shandle3,
74 curveID);
75 return_if_error(r, "Error in async function");
76
77 /* Set the timeout to indefinite for now, since we want _Finish to block */
78 int32_t timeouttmp = esysContext->timeout;
79 esysContext->timeout = -1;
80 /*
81 * Now we call the finish function, until return code is not equal to
82 * from TSS2_BASE_RC_TRY_AGAIN.
83 * Note that the finish function may return TSS2_RC_TRY_AGAIN, even if we
84 * have set the timeout to -1. This occurs for example if the TPM requests
85 * a retransmission of the command via TPM2_RC_YIELDED.
86 */
87 do {
88 r = Esys_EC_Ephemeral_Finish(esysContext, Q, counter);
89 /* This is just debug information about the reattempt to finish the
90 command */
91 if (base_rc(r) == TSS2_BASE_RC_TRY_AGAIN)
92 LOG_DEBUG("A layer below returned TRY_AGAIN: %" PRIx32
93 " => resubmitting command", r);
94 } while (base_rc(r) == TSS2_BASE_RC_TRY_AGAIN);
95
96 /* Restore the timeout value to the original value */
97 esysContext->timeout = timeouttmp;
98 return_if_error(r, "Esys Finish");
99
100 return TSS2_RC_SUCCESS;
101 }
102
103 /** Asynchronous function for TPM2_EC_Ephemeral
104 *
105 * This function invokes the TPM2_EC_Ephemeral command in a asynchronous
106 * variant. This means the function will return as soon as the command has been
107 * sent downwards the stack to the TPM. All input parameters are const.
108 * In order to retrieve the TPM's response call Esys_EC_Ephemeral_Finish.
109 *
110 * @param[in,out] esysContext The ESYS_CONTEXT.
111 * @param[in] shandle1 First session handle.
112 * @param[in] shandle2 Second session handle.
113 * @param[in] shandle3 Third session handle.
114 * @param[in] curveID The curve for the computed ephemeral point .
115 * @retval ESYS_RC_SUCCESS if the function call was a success.
116 * @retval TSS2_ESYS_RC_BAD_REFERENCE if the esysContext or required input
117 * pointers or required output handle references are NULL.
118 * @retval TSS2_ESYS_RC_BAD_CONTEXT: if esysContext corruption is detected.
119 * @retval TSS2_ESYS_RC_MEMORY: if the ESAPI cannot allocate enough memory for
120 * internal operations or return parameters.
121 * @retval TSS2_RCs produced by lower layers of the software stack may be
122 returned to the caller unaltered unless handled internally.
123 * @retval TSS2_ESYS_RC_MULTIPLE_DECRYPT_SESSIONS: if more than one session has
124 * the 'decrypt' attribute bit set.
125 * @retval TSS2_ESYS_RC_MULTIPLE_ENCRYPT_SESSIONS: if more than one session has
126 * the 'encrypt' attribute bit set.
127 * @retval TSS2_ESYS_RC_NO_DECRYPT_PARAM: if one of the sessions has the
128 * 'decrypt' attribute set and the command does not support encryption
129 * of the first command parameter.
130 */
131 TSS2_RC
Esys_EC_Ephemeral_Async(ESYS_CONTEXT * esysContext,ESYS_TR shandle1,ESYS_TR shandle2,ESYS_TR shandle3,TPMI_ECC_CURVE curveID)132 Esys_EC_Ephemeral_Async(
133 ESYS_CONTEXT *esysContext,
134 ESYS_TR shandle1,
135 ESYS_TR shandle2,
136 ESYS_TR shandle3,
137 TPMI_ECC_CURVE curveID)
138 {
139 TSS2_RC r;
140 LOG_TRACE("context=%p, curveID=%04"PRIx16"",
141 esysContext, curveID);
142 TSS2L_SYS_AUTH_COMMAND auths;
143
144 /* Check context, sequence correctness and set state to error for now */
145 if (esysContext == NULL) {
146 LOG_ERROR("esyscontext is NULL.");
147 return TSS2_ESYS_RC_BAD_REFERENCE;
148 }
149 r = iesys_check_sequence_async(esysContext);
150 if (r != TSS2_RC_SUCCESS)
151 return r;
152 esysContext->state = _ESYS_STATE_INTERNALERROR;
153
154 /* Check input parameters */
155 r = check_session_feasibility(shandle1, shandle2, shandle3, 0);
156 return_state_if_error(r, _ESYS_STATE_INIT, "Check session usage");
157
158 /* Initial invocation of SAPI to prepare the command buffer with parameters */
159 r = Tss2_Sys_EC_Ephemeral_Prepare(esysContext->sys, curveID);
160 return_state_if_error(r, _ESYS_STATE_INIT, "SAPI Prepare returned error.");
161
162 /* Calculate the cpHash Values */
163 r = init_session_tab(esysContext, shandle1, shandle2, shandle3);
164 return_state_if_error(r, _ESYS_STATE_INIT, "Initialize session resources");
165 iesys_compute_session_value(esysContext->session_tab[0], NULL, NULL);
166 iesys_compute_session_value(esysContext->session_tab[1], NULL, NULL);
167 iesys_compute_session_value(esysContext->session_tab[2], NULL, NULL);
168
169 /* Generate the auth values and set them in the SAPI command buffer */
170 r = iesys_gen_auths(esysContext, NULL, NULL, NULL, &auths);
171 return_state_if_error(r, _ESYS_STATE_INIT,
172 "Error in computation of auth values");
173
174 esysContext->authsCount = auths.count;
175 if (auths.count > 0) {
176 r = Tss2_Sys_SetCmdAuths(esysContext->sys, &auths);
177 return_state_if_error(r, _ESYS_STATE_INIT, "SAPI error on SetCmdAuths");
178 }
179
180 /* Trigger execution and finish the async invocation */
181 r = Tss2_Sys_ExecuteAsync(esysContext->sys);
182 return_state_if_error(r, _ESYS_STATE_INTERNALERROR,
183 "Finish (Execute Async)");
184
185 esysContext->state = _ESYS_STATE_SENT;
186
187 return r;
188 }
189
190 /** Asynchronous finish function for TPM2_EC_Ephemeral
191 *
192 * This function returns the results of a TPM2_EC_Ephemeral command
193 * invoked via Esys_EC_Ephemeral_Finish. All non-simple output parameters
194 * are allocated by the function's implementation. NULL can be passed for every
195 * output parameter if the value is not required.
196 *
197 * @param[in,out] esysContext The ESYS_CONTEXT.
198 * @param[out] Q Ephemeral public key Q := [r]G.
199 * (callee-allocated)
200 * @param[out] counter Least-significant 16 bits of commitCount.
201 * (callee-allocated)
202 * @retval TSS2_RC_SUCCESS on success
203 * @retval ESYS_RC_SUCCESS if the function call was a success.
204 * @retval TSS2_ESYS_RC_BAD_REFERENCE if the esysContext or required input
205 * pointers or required output handle references are NULL.
206 * @retval TSS2_ESYS_RC_BAD_CONTEXT: if esysContext corruption is detected.
207 * @retval TSS2_ESYS_RC_MEMORY: if the ESAPI cannot allocate enough memory for
208 * internal operations or return parameters.
209 * @retval TSS2_ESYS_RC_BAD_SEQUENCE: if the context has an asynchronous
210 * operation already pending.
211 * @retval TSS2_ESYS_RC_TRY_AGAIN: if the timeout counter expires before the
212 * TPM response is received.
213 * @retval TSS2_ESYS_RC_INSUFFICIENT_RESPONSE: if the TPM's response does not
214 * at least contain the tag, response length, and response code.
215 * @retval TSS2_ESYS_RC_RSP_AUTH_FAILED: if the response HMAC from the TPM did
216 * not verify.
217 * @retval TSS2_ESYS_RC_MALFORMED_RESPONSE: if the TPM's response is corrupted.
218 * @retval TSS2_RCs produced by lower layers of the software stack may be
219 * returned to the caller unaltered unless handled internally.
220 */
221 TSS2_RC
Esys_EC_Ephemeral_Finish(ESYS_CONTEXT * esysContext,TPM2B_ECC_POINT ** Q,UINT16 * counter)222 Esys_EC_Ephemeral_Finish(
223 ESYS_CONTEXT *esysContext,
224 TPM2B_ECC_POINT **Q,
225 UINT16 *counter)
226 {
227 TSS2_RC r;
228 LOG_TRACE("context=%p, Q=%p, counter=%p",
229 esysContext, Q, counter);
230
231 if (esysContext == NULL) {
232 LOG_ERROR("esyscontext is NULL.");
233 return TSS2_ESYS_RC_BAD_REFERENCE;
234 }
235
236 /* Check for correct sequence and set sequence to irregular for now */
237 if (esysContext->state != _ESYS_STATE_SENT &&
238 esysContext->state != _ESYS_STATE_RESUBMISSION) {
239 LOG_ERROR("Esys called in bad sequence.");
240 return TSS2_ESYS_RC_BAD_SEQUENCE;
241 }
242 esysContext->state = _ESYS_STATE_INTERNALERROR;
243
244 /* Allocate memory for response parameters */
245 if (Q != NULL) {
246 *Q = calloc(sizeof(TPM2B_ECC_POINT), 1);
247 if (*Q == NULL) {
248 return_error(TSS2_ESYS_RC_MEMORY, "Out of memory");
249 }
250 }
251
252 /*Receive the TPM response and handle resubmissions if necessary. */
253 r = Tss2_Sys_ExecuteFinish(esysContext->sys, esysContext->timeout);
254 if (base_rc(r) == TSS2_BASE_RC_TRY_AGAIN) {
255 LOG_DEBUG("A layer below returned TRY_AGAIN: %" PRIx32, r);
256 esysContext->state = _ESYS_STATE_SENT;
257 goto error_cleanup;
258 }
259 /* This block handle the resubmission of TPM commands given a certain set of
260 * TPM response codes. */
261 if (r == TPM2_RC_RETRY || r == TPM2_RC_TESTING || r == TPM2_RC_YIELDED) {
262 LOG_DEBUG("TPM returned RETRY, TESTING or YIELDED, which triggers a "
263 "resubmission: %" PRIx32, r);
264 if (esysContext->submissionCount++ >= _ESYS_MAX_SUBMISSIONS) {
265 LOG_WARNING("Maximum number of (re)submissions has been reached.");
266 esysContext->state = _ESYS_STATE_INIT;
267 goto error_cleanup;
268 }
269 esysContext->state = _ESYS_STATE_RESUBMISSION;
270 r = Tss2_Sys_ExecuteAsync(esysContext->sys);
271 if (r != TSS2_RC_SUCCESS) {
272 LOG_WARNING("Error attempting to resubmit");
273 /* We do not set esysContext->state here but inherit the most recent
274 * state of the _async function. */
275 goto error_cleanup;
276 }
277 r = TSS2_ESYS_RC_TRY_AGAIN;
278 LOG_DEBUG("Resubmission initiated and returning RC_TRY_AGAIN.");
279 goto error_cleanup;
280 }
281 /* The following is the "regular error" handling. */
282 if (iesys_tpm_error(r)) {
283 LOG_WARNING("Received TPM Error");
284 esysContext->state = _ESYS_STATE_INIT;
285 goto error_cleanup;
286 } else if (r != TSS2_RC_SUCCESS) {
287 LOG_ERROR("Received a non-TPM Error");
288 esysContext->state = _ESYS_STATE_INTERNALERROR;
289 goto error_cleanup;
290 }
291
292 /*
293 * Now the verification of the response (hmac check) and if necessary the
294 * parameter decryption have to be done.
295 */
296 r = iesys_check_response(esysContext);
297 goto_state_if_error(r, _ESYS_STATE_INTERNALERROR, "Error: check response",
298 error_cleanup);
299
300 /*
301 * After the verification of the response we call the complete function
302 * to deliver the result.
303 */
304 r = Tss2_Sys_EC_Ephemeral_Complete(esysContext->sys,
305 (Q != NULL) ? *Q : NULL, counter);
306 goto_state_if_error(r, _ESYS_STATE_INTERNALERROR,
307 "Received error from SAPI unmarshaling" ,
308 error_cleanup);
309
310 esysContext->state = _ESYS_STATE_INIT;
311
312 return TSS2_RC_SUCCESS;
313
314 error_cleanup:
315 if (Q != NULL)
316 SAFE_FREE(*Q);
317
318 return r;
319 }
320