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67#include <stdio.h>
68#include <stdlib.h>
69#include <string.h>
70#include <fcntl.h>
71#include <sys/ioctl.h>
72#include <unistd.h>
73#include <errno.h>
74#include <stdint.h>
75#include <stdbool.h>
76#include <bits/wordsize.h>
77#include <linux/mei.h>
78
79
80
81
82
83#define mei_msg(_me, fmt, ARGS...) do { \
84 if (_me->verbose) \
85 fprintf(stderr, fmt, ##ARGS); \
86} while (0)
87
88#define mei_err(_me, fmt, ARGS...) do { \
89 fprintf(stderr, "Error: " fmt, ##ARGS); \
90} while (0)
91
92struct mei {
93 uuid_le guid;
94 bool initialized;
95 bool verbose;
96 unsigned int buf_size;
97 unsigned char prot_ver;
98 int fd;
99};
100
101static void mei_deinit(struct mei *cl)
102{
103 if (cl->fd != -1)
104 close(cl->fd);
105 cl->fd = -1;
106 cl->buf_size = 0;
107 cl->prot_ver = 0;
108 cl->initialized = false;
109}
110
111static bool mei_init(struct mei *me, const uuid_le *guid,
112 unsigned char req_protocol_version, bool verbose)
113{
114 int result;
115 struct mei_client *cl;
116 struct mei_connect_client_data data;
117
118 me->verbose = verbose;
119
120 me->fd = open("/dev/mei0", O_RDWR);
121 if (me->fd == -1) {
122 mei_err(me, "Cannot establish a handle to the Intel MEI driver\n");
123 goto err;
124 }
125 memcpy(&me->guid, guid, sizeof(*guid));
126 memset(&data, 0, sizeof(data));
127 me->initialized = true;
128
129 memcpy(&data.in_client_uuid, &me->guid, sizeof(me->guid));
130 result = ioctl(me->fd, IOCTL_MEI_CONNECT_CLIENT, &data);
131 if (result) {
132 mei_err(me, "IOCTL_MEI_CONNECT_CLIENT receive message. err=%d\n", result);
133 goto err;
134 }
135 cl = &data.out_client_properties;
136 mei_msg(me, "max_message_length %d\n", cl->max_msg_length);
137 mei_msg(me, "protocol_version %d\n", cl->protocol_version);
138
139 if ((req_protocol_version > 0) &&
140 (cl->protocol_version != req_protocol_version)) {
141 mei_err(me, "Intel MEI protocol version not supported\n");
142 goto err;
143 }
144
145 me->buf_size = cl->max_msg_length;
146 me->prot_ver = cl->protocol_version;
147
148 return true;
149err:
150 mei_deinit(me);
151 return false;
152}
153
154static ssize_t mei_recv_msg(struct mei *me, unsigned char *buffer,
155 ssize_t len, unsigned long timeout)
156{
157 struct timeval tv;
158 fd_set set;
159 ssize_t rc;
160
161 tv.tv_sec = timeout / 1000;
162 tv.tv_usec = (timeout % 1000) * 1000000;
163
164 mei_msg(me, "call read length = %zd\n", len);
165
166 FD_ZERO(&set);
167 FD_SET(me->fd, &set);
168 rc = select(me->fd + 1, &set, NULL, NULL, &tv);
169 if (rc > 0 && FD_ISSET(me->fd, &set)) {
170 mei_msg(me, "have reply\n");
171 } else if (rc == 0) {
172 rc = -1;
173 mei_err(me, "read failed on timeout\n");
174 goto out;
175 } else {
176 rc = errno;
177 mei_err(me, "read failed on select with status %zd %s\n",
178 rc, strerror(errno));
179 goto out;
180 }
181
182 rc = read(me->fd, buffer, len);
183 if (rc < 0) {
184 mei_err(me, "read failed with status %zd %s\n",
185 rc, strerror(errno));
186 goto out;
187 }
188
189 mei_msg(me, "read succeeded with result %zd\n", rc);
190
191out:
192 if (rc < 0)
193 mei_deinit(me);
194
195 return rc;
196}
197
198static ssize_t mei_send_msg(struct mei *me, const unsigned char *buffer,
199 ssize_t len, unsigned long timeout)
200{
201 ssize_t written;
202 ssize_t rc;
203
204 mei_msg(me, "call write length = %zd\n", len);
205
206 written = write(me->fd, buffer, len);
207 if (written < 0) {
208 rc = -errno;
209 mei_err(me, "write failed with status %zd %s\n",
210 written, strerror(errno));
211 goto out;
212 }
213 mei_msg(me, "write success\n");
214
215 rc = written;
216out:
217 if (rc < 0)
218 mei_deinit(me);
219
220 return rc;
221}
222
223
224
225
226
227#define AMT_MAJOR_VERSION 1
228#define AMT_MINOR_VERSION 1
229
230#define AMT_STATUS_SUCCESS 0x0
231#define AMT_STATUS_INTERNAL_ERROR 0x1
232#define AMT_STATUS_NOT_READY 0x2
233#define AMT_STATUS_INVALID_AMT_MODE 0x3
234#define AMT_STATUS_INVALID_MESSAGE_LENGTH 0x4
235
236#define AMT_STATUS_HOST_IF_EMPTY_RESPONSE 0x4000
237#define AMT_STATUS_SDK_RESOURCES 0x1004
238
239
240#define AMT_BIOS_VERSION_LEN 65
241#define AMT_VERSIONS_NUMBER 50
242#define AMT_UNICODE_STRING_LEN 20
243
244struct amt_unicode_string {
245 uint16_t length;
246 char string[AMT_UNICODE_STRING_LEN];
247} __attribute__((packed));
248
249struct amt_version_type {
250 struct amt_unicode_string description;
251 struct amt_unicode_string version;
252} __attribute__((packed));
253
254struct amt_version {
255 uint8_t major;
256 uint8_t minor;
257} __attribute__((packed));
258
259struct amt_code_versions {
260 uint8_t bios[AMT_BIOS_VERSION_LEN];
261 uint32_t count;
262 struct amt_version_type versions[AMT_VERSIONS_NUMBER];
263} __attribute__((packed));
264
265
266
267
268
269struct amt_host_if_msg_header {
270 struct amt_version version;
271 uint16_t _reserved;
272 uint32_t command;
273 uint32_t length;
274} __attribute__((packed));
275
276struct amt_host_if_resp_header {
277 struct amt_host_if_msg_header header;
278 uint32_t status;
279 unsigned char data[];
280} __attribute__((packed));
281
282const uuid_le MEI_IAMTHIF = UUID_LE(0x12f80028, 0xb4b7, 0x4b2d, \
283 0xac, 0xa8, 0x46, 0xe0, 0xff, 0x65, 0x81, 0x4c);
284
285#define AMT_HOST_IF_CODE_VERSIONS_REQUEST 0x0400001A
286#define AMT_HOST_IF_CODE_VERSIONS_RESPONSE 0x0480001A
287
288const struct amt_host_if_msg_header CODE_VERSION_REQ = {
289 .version = {AMT_MAJOR_VERSION, AMT_MINOR_VERSION},
290 ._reserved = 0,
291 .command = AMT_HOST_IF_CODE_VERSIONS_REQUEST,
292 .length = 0
293};
294
295
296struct amt_host_if {
297 struct mei mei_cl;
298 unsigned long send_timeout;
299 bool initialized;
300};
301
302
303static bool amt_host_if_init(struct amt_host_if *acmd,
304 unsigned long send_timeout, bool verbose)
305{
306 acmd->send_timeout = (send_timeout) ? send_timeout : 20000;
307 acmd->initialized = mei_init(&acmd->mei_cl, &MEI_IAMTHIF, 0, verbose);
308 return acmd->initialized;
309}
310
311static void amt_host_if_deinit(struct amt_host_if *acmd)
312{
313 mei_deinit(&acmd->mei_cl);
314 acmd->initialized = false;
315}
316
317static uint32_t amt_verify_code_versions(const struct amt_host_if_resp_header *resp)
318{
319 uint32_t status = AMT_STATUS_SUCCESS;
320 struct amt_code_versions *code_ver;
321 size_t code_ver_len;
322 uint32_t ver_type_cnt;
323 uint32_t len;
324 uint32_t i;
325
326 code_ver = (struct amt_code_versions *)resp->data;
327
328 code_ver_len = resp->header.length - sizeof(uint32_t);
329 ver_type_cnt = code_ver_len -
330 sizeof(code_ver->bios) -
331 sizeof(code_ver->count);
332 if (code_ver->count != ver_type_cnt / sizeof(struct amt_version_type)) {
333 status = AMT_STATUS_INTERNAL_ERROR;
334 goto out;
335 }
336
337 for (i = 0; i < code_ver->count; i++) {
338 len = code_ver->versions[i].description.length;
339
340 if (len > AMT_UNICODE_STRING_LEN) {
341 status = AMT_STATUS_INTERNAL_ERROR;
342 goto out;
343 }
344
345 len = code_ver->versions[i].version.length;
346 if (code_ver->versions[i].version.string[len] != '\0' ||
347 len != strlen(code_ver->versions[i].version.string)) {
348 status = AMT_STATUS_INTERNAL_ERROR;
349 goto out;
350 }
351 }
352out:
353 return status;
354}
355
356static uint32_t amt_verify_response_header(uint32_t command,
357 const struct amt_host_if_msg_header *resp_hdr,
358 uint32_t response_size)
359{
360 if (response_size < sizeof(struct amt_host_if_resp_header)) {
361 return AMT_STATUS_INTERNAL_ERROR;
362 } else if (response_size != (resp_hdr->length +
363 sizeof(struct amt_host_if_msg_header))) {
364 return AMT_STATUS_INTERNAL_ERROR;
365 } else if (resp_hdr->command != command) {
366 return AMT_STATUS_INTERNAL_ERROR;
367 } else if (resp_hdr->_reserved != 0) {
368 return AMT_STATUS_INTERNAL_ERROR;
369 } else if (resp_hdr->version.major != AMT_MAJOR_VERSION ||
370 resp_hdr->version.minor < AMT_MINOR_VERSION) {
371 return AMT_STATUS_INTERNAL_ERROR;
372 }
373 return AMT_STATUS_SUCCESS;
374}
375
376static uint32_t amt_host_if_call(struct amt_host_if *acmd,
377 const unsigned char *command, ssize_t command_sz,
378 uint8_t **read_buf, uint32_t rcmd,
379 unsigned int expected_sz)
380{
381 uint32_t in_buf_sz;
382 ssize_t out_buf_sz;
383 ssize_t written;
384 uint32_t status;
385 struct amt_host_if_resp_header *msg_hdr;
386
387 in_buf_sz = acmd->mei_cl.buf_size;
388 *read_buf = (uint8_t *)malloc(sizeof(uint8_t) * in_buf_sz);
389 if (*read_buf == NULL)
390 return AMT_STATUS_SDK_RESOURCES;
391 memset(*read_buf, 0, in_buf_sz);
392 msg_hdr = (struct amt_host_if_resp_header *)*read_buf;
393
394 written = mei_send_msg(&acmd->mei_cl,
395 command, command_sz, acmd->send_timeout);
396 if (written != command_sz)
397 return AMT_STATUS_INTERNAL_ERROR;
398
399 out_buf_sz = mei_recv_msg(&acmd->mei_cl, *read_buf, in_buf_sz, 2000);
400 if (out_buf_sz <= 0)
401 return AMT_STATUS_HOST_IF_EMPTY_RESPONSE;
402
403 status = msg_hdr->status;
404 if (status != AMT_STATUS_SUCCESS)
405 return status;
406
407 status = amt_verify_response_header(rcmd,
408 &msg_hdr->header, out_buf_sz);
409 if (status != AMT_STATUS_SUCCESS)
410 return status;
411
412 if (expected_sz && expected_sz != out_buf_sz)
413 return AMT_STATUS_INTERNAL_ERROR;
414
415 return AMT_STATUS_SUCCESS;
416}
417
418
419static uint32_t amt_get_code_versions(struct amt_host_if *cmd,
420 struct amt_code_versions *versions)
421{
422 struct amt_host_if_resp_header *response = NULL;
423 uint32_t status;
424
425 status = amt_host_if_call(cmd,
426 (const unsigned char *)&CODE_VERSION_REQ,
427 sizeof(CODE_VERSION_REQ),
428 (uint8_t **)&response,
429 AMT_HOST_IF_CODE_VERSIONS_RESPONSE, 0);
430
431 if (status != AMT_STATUS_SUCCESS)
432 goto out;
433
434 status = amt_verify_code_versions(response);
435 if (status != AMT_STATUS_SUCCESS)
436 goto out;
437
438 memcpy(versions, response->data, sizeof(struct amt_code_versions));
439out:
440 if (response != NULL)
441 free(response);
442
443 return status;
444}
445
446
447int main(int argc, char **argv)
448{
449 struct amt_code_versions ver;
450 struct amt_host_if acmd;
451 unsigned int i;
452 uint32_t status;
453 int ret;
454 bool verbose;
455
456 verbose = (argc > 1 && strcmp(argv[1], "-v") == 0);
457
458 if (!amt_host_if_init(&acmd, 5000, verbose)) {
459 ret = 1;
460 goto out;
461 }
462
463 status = amt_get_code_versions(&acmd, &ver);
464
465 amt_host_if_deinit(&acmd);
466
467 switch (status) {
468 case AMT_STATUS_HOST_IF_EMPTY_RESPONSE:
469 printf("Intel AMT: DISABLED\n");
470 ret = 0;
471 break;
472 case AMT_STATUS_SUCCESS:
473 printf("Intel AMT: ENABLED\n");
474 for (i = 0; i < ver.count; i++) {
475 printf("%s:\t%s\n", ver.versions[i].description.string,
476 ver.versions[i].version.string);
477 }
478 ret = 0;
479 break;
480 default:
481 printf("An error has occurred\n");
482 ret = 1;
483 break;
484 }
485
486out:
487 return ret;
488}
489
