xref: /freebsd/usr.sbin/bhyve/tpm_ppi_qemu.c (revision a0ca4af9455b844c5e094fc1b09b1390ffa979fc)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2022 Beckhoff Automation GmbH & Co. KG
5  * Author: Corvin Köhne <c.koehne@beckhoff.com>
6  */
7 
8 #include <sys/types.h>
9 #include <sys/param.h>
10 #include <sys/endian.h>
11 #include <sys/linker_set.h>
12 
13 #include <machine/vmm.h>
14 
15 #include <assert.h>
16 #include <err.h>
17 #include <errno.h>
18 #include <vmmapi.h>
19 
20 #include "acpi.h"
21 #include "acpi_device.h"
22 #include "config.h"
23 #include "mem.h"
24 #include "qemu_fwcfg.h"
25 #include "tpm_ppi.h"
26 
27 #define TPM_PPI_ADDRESS 0xFED45000
28 #define TPM_PPI_SIZE 0x1000
29 
30 #define TPM_PPI_FWCFG_FILE "etc/tpm/config"
31 
32 #define TPM_PPI_QEMU_NAME "qemu"
33 
34 struct tpm_ppi_qemu {
35 	uint8_t func[256];	    // FUNC
36 	uint8_t in;		    // PPIN
37 	uint32_t ip;		    // PPIP
38 	uint32_t response;	    // PPRP
39 	uint32_t request;	    // PPRQ
40 	uint32_t request_parameter; // PPRM
41 	uint32_t last_request;	    // LPPR
42 	uint32_t func_ret;	    // FRET
43 	uint8_t _reserved1[0x40];   // RES1
44 	uint8_t next_step;	    // next_step
45 } __packed;
46 static_assert(sizeof(struct tpm_ppi_qemu) <= TPM_PPI_SIZE,
47     "Wrong size of tpm_ppi_qemu");
48 
49 struct tpm_ppi_fwcfg {
50 	uint32_t ppi_address;
51 	uint8_t tpm_version;
52 	uint8_t ppi_version;
53 } __packed;
54 
55 static int
56 tpm_ppi_mem_handler(struct vcpu *const vcpu __unused, const int dir,
57     const uint64_t addr, const int size, uint64_t *const val, void *const arg1,
58     const long arg2 __unused)
59 {
60 	struct tpm_ppi_qemu *ppi;
61 	uint8_t *ptr;
62 	uint64_t off;
63 
64 	if ((addr & (size - 1)) != 0) {
65 		warnx("%s: unaligned %s access @ %16lx [size = %x]", __func__,
66 		    (dir == MEM_F_READ) ? "read" : "write", addr, size);
67 	}
68 
69 	ppi = arg1;
70 
71 	off = addr - TPM_PPI_ADDRESS;
72 	ptr = (uint8_t *)ppi + off;
73 
74 	if (off > TPM_PPI_SIZE || off + size > TPM_PPI_SIZE) {
75 		return (EINVAL);
76 	}
77 
78 	assert(size == 1 || size == 2 || size == 4 || size == 8);
79 	if (dir == MEM_F_READ) {
80 		memcpy(val, ptr, size);
81 	} else {
82 		memcpy(ptr, val, size);
83 	}
84 
85 	return (0);
86 }
87 
88 static struct mem_range ppi_mmio = {
89 	.name = "ppi-mmio",
90 	.base = TPM_PPI_ADDRESS,
91 	.size = TPM_PPI_SIZE,
92 	.flags = MEM_F_RW,
93 	.handler = tpm_ppi_mem_handler,
94 };
95 
96 static int
97 tpm_ppi_init(void **sc)
98 {
99 	struct tpm_ppi_qemu *ppi = NULL;
100 	struct tpm_ppi_fwcfg *fwcfg = NULL;
101 	int error;
102 
103 	ppi = calloc(1, sizeof(*ppi));
104 	if (ppi == NULL) {
105 		warnx("%s: failed to allocate acpi region for ppi", __func__);
106 		error = ENOMEM;
107 		goto err_out;
108 	}
109 
110 	fwcfg = calloc(1, sizeof(struct tpm_ppi_fwcfg));
111 	if (fwcfg == NULL) {
112 		warnx("%s: failed to allocate fwcfg item", __func__);
113 		error = ENOMEM;
114 		goto err_out;
115 	}
116 
117 	fwcfg->ppi_address = htole32(TPM_PPI_ADDRESS);
118 	fwcfg->tpm_version = 2;
119 	fwcfg->ppi_version = 1;
120 
121 	error = qemu_fwcfg_add_file(TPM_PPI_FWCFG_FILE,
122 	    sizeof(struct tpm_ppi_fwcfg), fwcfg);
123 	if (error) {
124 		warnx("%s: failed to add fwcfg file", __func__);
125 		goto err_out;
126 	}
127 
128 	/*
129 	 * We would just need to create some guest memory for the PPI region.
130 	 * Sadly, bhyve has a strange memory interface. We can't just add more
131 	 * memory to the VM. So, create a trap instead which reads and writes to
132 	 * the ppi region. It's very slow but ppi shouldn't be used frequently.
133 	 */
134 	ppi_mmio.arg1 = ppi;
135 	error = register_mem(&ppi_mmio);
136 	if (error) {
137 		warnx("%s: failed to create trap for ppi accesses", __func__);
138 		goto err_out;
139 	}
140 
141 	*sc = ppi;
142 
143 	return (0);
144 
145 err_out:
146 	free(fwcfg);
147 	free(ppi);
148 
149 	return (error);
150 }
151 
152 static void
153 tpm_ppi_deinit(void *sc)
154 {
155 	struct tpm_ppi_qemu *ppi;
156 	int error;
157 
158 	if (sc == NULL)
159 		return;
160 
161 	ppi = sc;
162 
163 	error = unregister_mem(&ppi_mmio);
164 	assert(error == 0);
165 
166 	free(ppi);
167 }
168 
169 static int
170 tpm_ppi_write_dsdt_regions(void *sc __unused)
171 {
172 	/*
173 	 * struct tpm_ppi_qemu
174 	 */
175 	/*
176 	 * According to qemu the Windows ACPI parser has a bug that DerefOf is
177 	 * broken for SYSTEM_MEMORY. Due to that bug, qemu uses a dynamic
178 	 * operation region inside a method.
179 	 */
180 	dsdt_line("Method(TPFN, 1, Serialized)");
181 	dsdt_line("{");
182 	dsdt_line("  If(LGreaterEqual(Arg0, 0x100))");
183 	dsdt_line("  {");
184 	dsdt_line("    Return(Zero)");
185 	dsdt_line("  }");
186 	dsdt_line(
187 	    "  OperationRegion(TPP1, SystemMemory, Add(0x%8x, Arg0), One)",
188 	    TPM_PPI_ADDRESS);
189 	dsdt_line("  Field(TPP1, ByteAcc, NoLock, Preserve)");
190 	dsdt_line("  {");
191 	dsdt_line("    TPPF, 8,");
192 	dsdt_line("  }");
193 	dsdt_line("  Return(TPPF)");
194 	dsdt_line("}");
195 	dsdt_line("OperationRegion(TPP2, SystemMemory, 0x%8x, 0x%x)",
196 	    TPM_PPI_ADDRESS + 0x100, 0x5A);
197 	dsdt_line("Field(TPP2, AnyAcc, NoLock, Preserve)");
198 	dsdt_line("{");
199 	dsdt_line("  PPIN, 8,");
200 	dsdt_line("  PPIP, 32,");
201 	dsdt_line("  PPRP, 32,");
202 	dsdt_line("  PPRQ, 32,");
203 	dsdt_line("  PPRM, 32,");
204 	dsdt_line("  LPPR, 32,");
205 	dsdt_line("}");
206 	/*
207 	 * Used for TCG Platform Reset Attack Mitigation
208 	 */
209 	dsdt_line("OperationRegion(TPP3, SystemMemory, 0x%8x, 1)",
210 	    TPM_PPI_ADDRESS + sizeof(struct tpm_ppi_qemu));
211 	dsdt_line("Field(TPP3, ByteAcc, NoLock, Preserve)");
212 	dsdt_line("{");
213 	dsdt_line("  MOVV, 8,");
214 	dsdt_line("}");
215 
216 	return (0);
217 }
218 
219 static int
220 tpm_ppi_write_dsdt_dsm(void *sc __unused)
221 {
222 	/*
223 	 * Physical Presence Interface
224 	 */
225 	dsdt_line(
226 	    "If(LEqual(Arg0, ToUUID(\"3DDDFAA6-361B-4EB4-A424-8D10089D1653\"))) /* UUID */");
227 	dsdt_line("{");
228 	/*
229 	 * Function 0 - _DSM Query Function
230 	 * Arguments:
231 	 *   Empty Package
232 	 * Return:
233 	 *   Buffer - Index field of supported functions
234 	 */
235 	dsdt_line("  If(LEqual(Arg2, 0)) /* Function */");
236 	dsdt_line("  {");
237 	dsdt_line("    Return(Buffer(0x02)");
238 	dsdt_line("    {");
239 	dsdt_line("      0xFF, 0x01");
240 	dsdt_line("    })");
241 	dsdt_line("  }");
242 	/*
243 	 * Function 1 - Get Physical Presence Interface Version
244 	 * Arguments:
245 	 *   Empty Package
246 	 * Return:
247 	 *   String - Supported Physical Presence Interface revision
248 	 */
249 	dsdt_line("  If(LEqual(Arg2, 1)) /* Function */");
250 	dsdt_line("  {");
251 	dsdt_line("    Return(\"1.3\")");
252 	dsdt_line("  }");
253 	/*
254 	 * Function 2 - Submit TPM Operation Request to Pre-OS Environment
255 	 * !!!DEPRECATED BUT MANDATORY!!!
256 	 * Arguments:
257 	 *   Integer - Operation Value of the Request
258 	 * Return:
259 	 *   Integer - Function Return Code
260 	 *     0 - Success
261 	 *     1 - Operation Value of the Request Not Supported
262 	 *     2 - General Failure
263 	 */
264 	dsdt_line("  If(LEqual(Arg2, 2)) /* Function */");
265 	dsdt_line("  {");
266 	dsdt_line("    Store(DerefOf(Index(Arg3, 0)), Local0)");
267 	dsdt_line("    Store(TPFN(Local0), Local1)");
268 	dsdt_line("    If (LEqual(And(Local1, 7), 0))");
269 	dsdt_line("    {");
270 	dsdt_line("      Return(1)");
271 	dsdt_line("    }");
272 	dsdt_line("    Store(Local0, PPRQ)");
273 	dsdt_line("    Store(0, PPRM)");
274 	dsdt_line("    Return(0)");
275 	dsdt_line("  }");
276 	/*
277 	 * Function 3 - Get Pending TPM Operation Request By the OS
278 	 * Arguments:
279 	 *   Empty Package
280 	 * Return:
281 	 *   Package
282 	 *     Integer 1 - Function Return Code
283 	 *       0 - Success
284 	 *       1 - General Failure
285 	 *     Integer 2 - Pending operation requested by the OS
286 	 *       0 - None
287 	 *      >0 - Operation Value of the Pending Request
288 	 *     Integer 3 - Optional argument to pending operation requested by
289 	 *                 the OS
290 	 *       0 - None
291 	 *      >0 - Argument of the Pending Request
292 	 */
293 	dsdt_line("  If(LEqual(Arg2, 3)) /* Function */");
294 	dsdt_line("  {");
295 	dsdt_line("    If(LEqual(Arg1, 1)) /* Revision */");
296 	dsdt_line("    {");
297 	dsdt_line("      Store(PPRQ, Index(TPM2, 1))");
298 	dsdt_line("      Return(TPM2)");
299 	dsdt_line("    }");
300 	dsdt_line("    If(LEqual(Arg1, 2)) /* Revision */");
301 	dsdt_line("    {");
302 	dsdt_line("      Store(PPRQ, Index(TPM3, 1))");
303 	dsdt_line("      Store(PPRM, Index(TPM3, 2))");
304 	dsdt_line("      Return(TPM3)");
305 	dsdt_line("    }");
306 	dsdt_line("  }");
307 	/*
308 	 * Function 4 - Get Platform-Specific Action to Transition to Pre-OS
309 	 *              Environment
310 	 * Arguments:
311 	 *   Empty Package
312 	 * Return:
313 	 *   Integer - Action that the OS should take to transition to the
314 	 *             pre-OS environment for execution of a requested operation
315 	 *     0 - None
316 	 *     1 - Shutdown
317 	 *     2 - Reboot
318 	 *     3 - OS Vendor-specific
319 	 */
320 	dsdt_line("  If(LEqual(Arg2, 4)) /* Function */");
321 	dsdt_line("  {");
322 	dsdt_line("    Return(2)");
323 	dsdt_line("  }");
324 	/*
325 	 * Function 5 - Return TPM Operation Response to OS Environment
326 	 * Arguments:
327 	 *   Empty Package
328 	 * Return:
329 	 *   Package
330 	 *     Integer 1 - Function Return Code
331 	 *       0 - Success
332 	 *       1 - General Failure
333 	 *     Integer 2 - Most recent operation request
334 	 *       0 - None
335 	 *      >0 - Operation value of the most recent request
336 	 *     Integer 3 - Response to the most recent operation request
337 	 *       0 - Success
338 	 *       0x00000001..0x000000FF - Corresponding TPM error code
339 	 *       0xFFFFFFF0 - User Abort or timeout of dialog
340 	 *       0xFFFFFFF1 - firmware failure
341 	 */
342 	dsdt_line("  If(LEqual(Arg2, 5)) /* Function */");
343 	dsdt_line("  {");
344 	dsdt_line("    Store(LPPR, Index(TPM3, 1))");
345 	dsdt_line("    Store(PPRP, Index(TPM3, 2))");
346 	dsdt_line("    Return(TPM3)");
347 	dsdt_line("  }");
348 	/*
349 	 * Function 6 - Submit preferred user language
350 	 * !!!DEPRECATED BUT MANDATORY!!!
351 	 * Arguments:
352 	 *   Package
353 	 *     String - Preferred language code
354 	 * Return:
355 	 *   Integer
356 	 *     3 - Not implemented
357 	 */
358 	dsdt_line("  If(LEqual(Arg2, 6)) /* Function */");
359 	dsdt_line("  {");
360 	dsdt_line("    Return(3)");
361 	dsdt_line("  }");
362 	/*
363 	 * Function 7 - Submit TPM Operation Request to Pre-OS Environment 2
364 	 * Arguments:
365 	 *   Package
366 	 *     Integer 1 - Operation Value of the Request
367 	 *     Integer 2 - Argument for Operation
368 	 * Return:
369 	 *   Integer - Function Return Code
370 	 *     0 - Success
371 	 *     1 - Not Implemented
372 	 *     2 - General Failure
373 	 *     3 - Operation blocked by current firmware settings
374 	 */
375 	dsdt_line("  If(LEqual(Arg2, 7)) /* Function */");
376 	dsdt_line("  {");
377 	dsdt_line("    Store(DerefOf(Index(Arg3, 0)), Local0)");
378 	dsdt_line("    Store(TPFN(Local0), Local1)");
379 	dsdt_line("    If (LEqual(And(Local1, 7), 0)) /* Not Implemented */");
380 	dsdt_line("    {");
381 	dsdt_line("      Return(1)");
382 	dsdt_line("    }");
383 	dsdt_line("    If (LEqual(And(Local1, 7), 2)) /* Blocked */ ");
384 	dsdt_line("    {");
385 	dsdt_line("      Return(3)");
386 	dsdt_line("    }");
387 	dsdt_line("    If(LEqual(Arg1, 1)) /* Revision */");
388 	dsdt_line("    {");
389 	dsdt_line("      Store(Local0, PPRQ)");
390 	dsdt_line("      Store(0, PPRM)");
391 	dsdt_line("    }");
392 	dsdt_line("    If(LEqual(Arg1, 2)) /* Revision */");
393 	dsdt_line("    {");
394 	dsdt_line("      Store(Local0, PPRQ)");
395 	dsdt_line("      Store(DerefOf(Index(Arg3, 1)), PPRM)");
396 	dsdt_line("    }");
397 	dsdt_line("    Return(0)");
398 	dsdt_line("  }");
399 	/*
400 	 * Function 8 - Get User Confirmation Status for Operation
401 	 * Arguments:
402 	 *   Package
403 	 *     Integer - Operation Value that may need user confirmation
404 	 * Return:
405 	 *   Integer - Function Return Code
406 	 *     0 - Not implemented
407 	 *     1 - Firmware only
408 	 *     2 - Blocked for OS by firmware configuration
409 	 *     3 - Allowed and physically present user required
410 	 *     4 - Allowed and physically present user not required
411 	 */
412 	dsdt_line("    If(LEqual(Arg2, 8)) /* Function */");
413 	dsdt_line("    {");
414 	dsdt_line("      Store(DerefOf(Index(Arg3, 0)), Local0)");
415 	dsdt_line("      Store(TPFN(Local0), Local1)");
416 	dsdt_line("      Return(And(Local1, 7))");
417 	dsdt_line("    }");
418 	/*
419 	 * Unknown function
420 	 */
421 	dsdt_line("  Return(Buffer(1)");
422 	dsdt_line("  {");
423 	dsdt_line("    0x00");
424 	dsdt_line("  })");
425 	dsdt_line("}");
426 
427 	/*
428 	 * TCG Platform Reset Attack Mitigation
429 	 */
430 	dsdt_line(
431 	    "If(LEqual(Arg0, ToUUID(\"376054ED-CC13-4675-901C-4756D7F2D45D\"))) /* UUID */");
432 	dsdt_line("{");
433 	/*
434 	 * Function 0 - _DSM Query Function
435 	 * Arguments:
436 	 *   Empty Package
437 	 * Return:
438 	 *   Buffer - Index field of supported functions
439 	 */
440 	dsdt_line("  If(LEqual(Arg2, 0)) /* Function */");
441 	dsdt_line("  {");
442 	dsdt_line("    Return(Buffer(1)");
443 	dsdt_line("    {");
444 	dsdt_line("      0x03");
445 	dsdt_line("    })");
446 	dsdt_line("  }");
447 	/*
448 	 * Function 1 - Memory Clear
449 	 * Arguments:
450 	 *   Package
451 	 *     Integer - Operation Value of the Request
452 	 * Return:
453 	 *   Integer - Function Return Code
454 	 *     0 - Success
455 	 *     1 - General Failure
456 	 */
457 	dsdt_line("  If(LEqual(Arg2, 1)) /* Function */");
458 	dsdt_line("  {");
459 	dsdt_line("    Store(DerefOf(Index(Arg3, 0)), Local0)");
460 	dsdt_line("    Store(Local0, MOVV)");
461 	dsdt_line("    Return(0)");
462 	dsdt_line("  }");
463 	dsdt_line("}");
464 
465 	return (0);
466 }
467 
468 static struct tpm_ppi tpm_ppi_qemu = {
469 	.name = TPM_PPI_QEMU_NAME,
470 	.init = tpm_ppi_init,
471 	.deinit = tpm_ppi_deinit,
472 	.write_dsdt_regions = tpm_ppi_write_dsdt_regions,
473 	.write_dsdt_dsm = tpm_ppi_write_dsdt_dsm,
474 };
475 TPM_PPI_SET(tpm_ppi_qemu);
476