virt/coco/tsm.c

25  * The TSM report interface is a common provider of blobs that facilitate
27  * service. A TSM report combines a user-defined blob (likely a public-key with
28  * a nonce for a key-exchange protocol) with a signed attestation report. That
30  * validate the attestation report. The expectation is that this interface is
32  * own their own report generation instances to generate reports as
35  * The attestation report format is TSM provider specific, when / if a standard
42 	struct tsm_report report;
58 	return &state->report;
61 static struct tsm_report_state *to_state(struct tsm_report *report)
63 	return container_of(report, struct tsm_report_state, report);
66 static int try_advance_write_generation(struct tsm_report *report)
68 	struct tsm_report_state *state = to_state(report);
75 	 * interim read. Stop accepting updates until the current report
87 	struct tsm_report *report = to_tsm_report(cfg);
105 	rc = try_advance_write_generation(report);
108 	report->desc.privlevel = val;
125 	struct tsm_report *report = to_tsm_report(cfg);
129 	rc = try_advance_write_generation(report);
133 	report->desc.inblob_len = count;
134 	memcpy(report->desc.inblob, buf, count);
141 	struct tsm_report *report = to_tsm_report(cfg);
142 	struct tsm_report_state *state = to_state(report);
156 static ssize_t __read_report(struct tsm_report *report, void *buf, size_t count,
164 		out = report->outblob;
165 		len = report->outblob_len;
167 		out = report->auxblob;
168 		len = report->auxblob_len;
180 static ssize_t read_cached_report(struct tsm_report *report, void *buf,
183 	struct tsm_report_state *state = to_state(report);
186 	if (!report->desc.inblob_len)
191 	 * whether the report includes an auxblob or not.
193 	if (!report->outblob ||
197 	return __read_report(report, buf, count, select);
200 static ssize_t tsm_report_read(struct tsm_report *report, void *buf,
203 	struct tsm_report_state *state = to_state(report);
207 	/* try to read from the existing report if present and valid... */
208 	rc = read_cached_report(report, buf, count, select);
212 	/* slow path, report may need to be regenerated... */
217 	if (!report->desc.inblob_len)
220 	/* did another thread already generate this report? */
221 	if (report->outblob &&
225 	kvfree(report->outblob);
226 	kvfree(report->auxblob);
227 	report->outblob = NULL;
228 	report->auxblob = NULL;
229 	rc = ops->report_new(report, provider.data);
234 	return __read_report(report, buf, count, select);
240 	struct tsm_report *report = to_tsm_report(cfg);
242 	return tsm_report_read(report, buf, count, TSM_REPORT);
249 	struct tsm_report *report = to_tsm_report(cfg);
251 	return tsm_report_read(report, buf, count, TSM_CERTS);
288 	struct tsm_report *report = to_tsm_report(cfg);
289 	struct tsm_report_state *state = to_state(report);
291 	kvfree(report->auxblob);
292 	kvfree(report->outblob);
405 	tsm = configfs_register_default_group(root, "report",