rpmb.c 12 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488
  1. // SPDX-License-Identifier: GPL-2.0+
  2. /*
  3. * Copyright 2014, Staubli Faverges
  4. * Pierre Aubert
  5. *
  6. * eMMC- Replay Protected Memory Block
  7. * According to JEDEC Standard No. 84-A441
  8. */
  9. #include <config.h>
  10. #include <common.h>
  11. #include <memalign.h>
  12. #include <mmc.h>
  13. #include <sdhci.h>
  14. #include <u-boot/sha256.h>
  15. #include "mmc_private.h"
  16. /* Request codes */
  17. #define RPMB_REQ_KEY 1
  18. #define RPMB_REQ_WCOUNTER 2
  19. #define RPMB_REQ_WRITE_DATA 3
  20. #define RPMB_REQ_READ_DATA 4
  21. #define RPMB_REQ_STATUS 5
  22. /* Response code */
  23. #define RPMB_RESP_KEY 0x0100
  24. #define RPMB_RESP_WCOUNTER 0x0200
  25. #define RPMB_RESP_WRITE_DATA 0x0300
  26. #define RPMB_RESP_READ_DATA 0x0400
  27. /* Error codes */
  28. #define RPMB_OK 0
  29. #define RPMB_ERR_GENERAL 1
  30. #define RPMB_ERR_AUTH 2
  31. #define RPMB_ERR_COUNTER 3
  32. #define RPMB_ERR_ADDRESS 4
  33. #define RPMB_ERR_WRITE 5
  34. #define RPMB_ERR_READ 6
  35. #define RPMB_ERR_KEY 7
  36. #define RPMB_ERR_CNT_EXPIRED 0x80
  37. #define RPMB_ERR_MSK 0x7
  38. /* Sizes of RPMB data frame */
  39. #define RPMB_SZ_STUFF 196
  40. #define RPMB_SZ_MAC 32
  41. #define RPMB_SZ_DATA 256
  42. #define RPMB_SZ_NONCE 16
  43. #define SHA256_BLOCK_SIZE 64
  44. /* Error messages */
  45. static const char * const rpmb_err_msg[] = {
  46. "",
  47. "General failure",
  48. "Authentication failure",
  49. "Counter failure",
  50. "Address failure",
  51. "Write failure",
  52. "Read failure",
  53. "Authentication key not yet programmed",
  54. };
  55. /* Structure of RPMB data frame. */
  56. struct s_rpmb {
  57. unsigned char stuff[RPMB_SZ_STUFF];
  58. unsigned char mac[RPMB_SZ_MAC];
  59. unsigned char data[RPMB_SZ_DATA];
  60. unsigned char nonce[RPMB_SZ_NONCE];
  61. unsigned int write_counter;
  62. unsigned short address;
  63. unsigned short block_count;
  64. unsigned short result;
  65. unsigned short request;
  66. };
  67. static int mmc_set_blockcount(struct mmc *mmc, unsigned int blockcount,
  68. bool is_rel_write)
  69. {
  70. struct mmc_cmd cmd = {0};
  71. cmd.cmdidx = MMC_CMD_SET_BLOCK_COUNT;
  72. cmd.cmdarg = blockcount & 0x0000FFFF;
  73. if (is_rel_write)
  74. cmd.cmdarg |= 1 << 31;
  75. cmd.resp_type = MMC_RSP_R1;
  76. return mmc_send_cmd(mmc, &cmd, NULL);
  77. }
  78. static int mmc_rpmb_request(struct mmc *mmc, const struct s_rpmb *s,
  79. unsigned int count, bool is_rel_write)
  80. {
  81. struct mmc_cmd cmd = {0};
  82. struct mmc_data data;
  83. struct sdhci_host *host = mmc->priv;
  84. int ret;
  85. ret = mmc_set_blockcount(mmc, count, is_rel_write);
  86. if (ret) {
  87. #ifdef CONFIG_MMC_RPMB_TRACE
  88. printf("%s:mmc_set_blockcount-> %d\n", __func__, ret);
  89. #endif
  90. return 1;
  91. }
  92. cmd.cmdidx = MMC_CMD_WRITE_MULTIPLE_BLOCK;
  93. cmd.cmdarg = 0;
  94. cmd.resp_type = MMC_RSP_R1;
  95. if (host->quirks & SDHCI_QUIRK_BROKEN_R1B)
  96. cmd.resp_type = MMC_RSP_R1;
  97. data.src = (const char *)s;
  98. data.blocks = 1;
  99. data.blocksize = MMC_MAX_BLOCK_LEN;
  100. data.flags = MMC_DATA_WRITE;
  101. ret = mmc_send_cmd(mmc, &cmd, &data);
  102. if (ret) {
  103. #ifdef CONFIG_MMC_RPMB_TRACE
  104. printf("%s:mmc_send_cmd-> %d\n", __func__, ret);
  105. #endif
  106. return 1;
  107. }
  108. return 0;
  109. }
  110. static int mmc_rpmb_response(struct mmc *mmc, struct s_rpmb *s,
  111. unsigned short expected)
  112. {
  113. struct mmc_cmd cmd = {0};
  114. struct mmc_data data;
  115. int ret;
  116. ret = mmc_set_blockcount(mmc, 1, false);
  117. if (ret) {
  118. #ifdef CONFIG_MMC_RPMB_TRACE
  119. printf("%s:mmc_set_blockcount-> %d\n", __func__, ret);
  120. #endif
  121. return -1;
  122. }
  123. cmd.cmdidx = MMC_CMD_READ_MULTIPLE_BLOCK;
  124. cmd.cmdarg = 0;
  125. cmd.resp_type = MMC_RSP_R1;
  126. data.dest = (char *)s;
  127. data.blocks = 1;
  128. data.blocksize = MMC_MAX_BLOCK_LEN;
  129. data.flags = MMC_DATA_READ;
  130. ret = mmc_send_cmd(mmc, &cmd, &data);
  131. if (ret) {
  132. #ifdef CONFIG_MMC_RPMB_TRACE
  133. printf("%s:mmc_send_cmd-> %d\n", __func__, ret);
  134. #endif
  135. return -1;
  136. }
  137. /* Check the response and the status */
  138. if (be16_to_cpu(s->request) != expected) {
  139. #ifdef CONFIG_MMC_RPMB_TRACE
  140. printf("%s:response= %x\n", __func__,
  141. be16_to_cpu(s->request));
  142. #endif
  143. return -1;
  144. }
  145. ret = be16_to_cpu(s->result);
  146. if (ret) {
  147. printf("%s %s\n", rpmb_err_msg[ret & RPMB_ERR_MSK],
  148. (ret & RPMB_ERR_CNT_EXPIRED) ?
  149. "Write counter has expired" : "");
  150. }
  151. /* Return the status of the command */
  152. return ret;
  153. }
  154. static int mmc_rpmb_status(struct mmc *mmc, unsigned short expected)
  155. {
  156. ALLOC_CACHE_ALIGN_BUFFER(struct s_rpmb, rpmb_frame, 1);
  157. memset(rpmb_frame, 0, sizeof(struct s_rpmb));
  158. rpmb_frame->request = cpu_to_be16(RPMB_REQ_STATUS);
  159. if (mmc_rpmb_request(mmc, rpmb_frame, 1, false))
  160. return -1;
  161. /* Read the result */
  162. return mmc_rpmb_response(mmc, rpmb_frame, expected);
  163. }
  164. static void rpmb_hmac(unsigned char *key, unsigned char *buff, int len,
  165. unsigned char *output)
  166. {
  167. sha256_context ctx;
  168. int i;
  169. unsigned char k_ipad[SHA256_BLOCK_SIZE];
  170. unsigned char k_opad[SHA256_BLOCK_SIZE];
  171. sha256_starts(&ctx);
  172. /* According to RFC 4634, the HMAC transform looks like:
  173. SHA(K XOR opad, SHA(K XOR ipad, text))
  174. where K is an n byte key.
  175. ipad is the byte 0x36 repeated blocksize times
  176. opad is the byte 0x5c repeated blocksize times
  177. and text is the data being protected.
  178. */
  179. for (i = 0; i < RPMB_SZ_MAC; i++) {
  180. k_ipad[i] = key[i] ^ 0x36;
  181. k_opad[i] = key[i] ^ 0x5c;
  182. }
  183. /* remaining pad bytes are '\0' XOR'd with ipad and opad values */
  184. for ( ; i < SHA256_BLOCK_SIZE; i++) {
  185. k_ipad[i] = 0x36;
  186. k_opad[i] = 0x5c;
  187. }
  188. sha256_update(&ctx, k_ipad, SHA256_BLOCK_SIZE);
  189. sha256_update(&ctx, buff, len);
  190. sha256_finish(&ctx, output);
  191. /* Init context for second pass */
  192. sha256_starts(&ctx);
  193. /* start with outer pad */
  194. sha256_update(&ctx, k_opad, SHA256_BLOCK_SIZE);
  195. /* then results of 1st hash */
  196. sha256_update(&ctx, output, RPMB_SZ_MAC);
  197. /* finish up 2nd pass */
  198. sha256_finish(&ctx, output);
  199. }
  200. int mmc_rpmb_get_counter(struct mmc *mmc, unsigned long *pcounter)
  201. {
  202. int ret;
  203. ALLOC_CACHE_ALIGN_BUFFER(struct s_rpmb, rpmb_frame, 1);
  204. /* Fill the request */
  205. memset(rpmb_frame, 0, sizeof(struct s_rpmb));
  206. rpmb_frame->request = cpu_to_be16(RPMB_REQ_WCOUNTER);
  207. if (mmc_rpmb_request(mmc, rpmb_frame, 1, false))
  208. return -1;
  209. /* Read the result */
  210. ret = mmc_rpmb_response(mmc, rpmb_frame, RPMB_RESP_WCOUNTER);
  211. if (ret)
  212. return ret;
  213. *pcounter = be32_to_cpu(rpmb_frame->write_counter);
  214. return 0;
  215. }
  216. int mmc_rpmb_set_key(struct mmc *mmc, void *key)
  217. {
  218. ALLOC_CACHE_ALIGN_BUFFER(struct s_rpmb, rpmb_frame, 1);
  219. /* Fill the request */
  220. memset(rpmb_frame, 0, sizeof(struct s_rpmb));
  221. rpmb_frame->request = cpu_to_be16(RPMB_REQ_KEY);
  222. memcpy(rpmb_frame->mac, key, RPMB_SZ_MAC);
  223. if (mmc_rpmb_request(mmc, rpmb_frame, 1, true))
  224. return -1;
  225. /* read the operation status */
  226. return mmc_rpmb_status(mmc, RPMB_RESP_KEY);
  227. }
  228. int mmc_rpmb_read(struct mmc *mmc, void *addr, unsigned short blk,
  229. unsigned short cnt, unsigned char *key)
  230. {
  231. ALLOC_CACHE_ALIGN_BUFFER(struct s_rpmb, rpmb_frame, 1);
  232. int i;
  233. for (i = 0; i < cnt; i++) {
  234. /* Fill the request */
  235. memset(rpmb_frame, 0, sizeof(struct s_rpmb));
  236. rpmb_frame->address = cpu_to_be16(blk + i);
  237. rpmb_frame->request = cpu_to_be16(RPMB_REQ_READ_DATA);
  238. if (mmc_rpmb_request(mmc, rpmb_frame, 1, false))
  239. break;
  240. /* Read the result */
  241. if (mmc_rpmb_response(mmc, rpmb_frame, RPMB_RESP_READ_DATA))
  242. break;
  243. /* Check the HMAC if key is provided */
  244. if (key) {
  245. unsigned char ret_hmac[RPMB_SZ_MAC];
  246. rpmb_hmac(key, rpmb_frame->data, 284, ret_hmac);
  247. if (memcmp(ret_hmac, rpmb_frame->mac, RPMB_SZ_MAC)) {
  248. printf("MAC error on block #%d\n", i);
  249. break;
  250. }
  251. }
  252. /* Copy data */
  253. memcpy(addr + i * RPMB_SZ_DATA, rpmb_frame->data, RPMB_SZ_DATA);
  254. }
  255. return i;
  256. }
  257. int mmc_rpmb_write(struct mmc *mmc, void *addr, unsigned short blk,
  258. unsigned short cnt, unsigned char *key)
  259. {
  260. ALLOC_CACHE_ALIGN_BUFFER(struct s_rpmb, rpmb_frame, 1);
  261. unsigned long wcount;
  262. int i;
  263. for (i = 0; i < cnt; i++) {
  264. if (mmc_rpmb_get_counter(mmc, &wcount)) {
  265. printf("Cannot read RPMB write counter\n");
  266. break;
  267. }
  268. /* Fill the request */
  269. memset(rpmb_frame, 0, sizeof(struct s_rpmb));
  270. memcpy(rpmb_frame->data, addr + i * RPMB_SZ_DATA, RPMB_SZ_DATA);
  271. rpmb_frame->address = cpu_to_be16(blk + i);
  272. rpmb_frame->block_count = cpu_to_be16(1);
  273. rpmb_frame->write_counter = cpu_to_be32(wcount);
  274. rpmb_frame->request = cpu_to_be16(RPMB_REQ_WRITE_DATA);
  275. /* Computes HMAC */
  276. rpmb_hmac(key, rpmb_frame->data, 284, rpmb_frame->mac);
  277. if (mmc_rpmb_request(mmc, rpmb_frame, 1, true))
  278. break;
  279. /* Get status */
  280. if (mmc_rpmb_status(mmc, RPMB_RESP_WRITE_DATA))
  281. break;
  282. }
  283. return i;
  284. }
  285. static int send_write_mult_block(struct mmc *mmc, const struct s_rpmb *frm,
  286. unsigned short cnt)
  287. {
  288. struct mmc_cmd cmd = {
  289. .cmdidx = MMC_CMD_WRITE_MULTIPLE_BLOCK,
  290. .resp_type = MMC_RSP_R1,
  291. };
  292. struct mmc_data data = {
  293. .src = (const void *)frm,
  294. .blocks = cnt,
  295. .blocksize = sizeof(*frm),
  296. .flags = MMC_DATA_WRITE,
  297. };
  298. return mmc_send_cmd(mmc, &cmd, &data);
  299. }
  300. static int send_read_mult_block(struct mmc *mmc, struct s_rpmb *frm,
  301. unsigned short cnt)
  302. {
  303. struct mmc_cmd cmd = {
  304. .cmdidx = MMC_CMD_READ_MULTIPLE_BLOCK,
  305. .resp_type = MMC_RSP_R1,
  306. };
  307. struct mmc_data data = {
  308. .dest = (void *)frm,
  309. .blocks = cnt,
  310. .blocksize = sizeof(*frm),
  311. .flags = MMC_DATA_READ,
  312. };
  313. return mmc_send_cmd(mmc, &cmd, &data);
  314. }
  315. static int rpmb_route_write_req(struct mmc *mmc, struct s_rpmb *req,
  316. unsigned short req_cnt, struct s_rpmb *rsp,
  317. unsigned short rsp_cnt)
  318. {
  319. int ret;
  320. /*
  321. * Send the write request.
  322. */
  323. ret = mmc_set_blockcount(mmc, req_cnt, true);
  324. if (ret)
  325. return ret;
  326. ret = send_write_mult_block(mmc, req, req_cnt);
  327. if (ret)
  328. return ret;
  329. /*
  330. * Read the result of the request.
  331. */
  332. ret = mmc_set_blockcount(mmc, 1, false);
  333. if (ret)
  334. return ret;
  335. memset(rsp, 0, sizeof(*rsp));
  336. rsp->request = cpu_to_be16(RPMB_REQ_STATUS);
  337. ret = send_write_mult_block(mmc, rsp, 1);
  338. if (ret)
  339. return ret;
  340. ret = mmc_set_blockcount(mmc, 1, false);
  341. if (ret)
  342. return ret;
  343. return send_read_mult_block(mmc, rsp, 1);
  344. }
  345. static int rpmb_route_read_req(struct mmc *mmc, struct s_rpmb *req,
  346. unsigned short req_cnt, struct s_rpmb *rsp,
  347. unsigned short rsp_cnt)
  348. {
  349. int ret;
  350. /*
  351. * Send the read request.
  352. */
  353. ret = mmc_set_blockcount(mmc, 1, false);
  354. if (ret)
  355. return ret;
  356. ret = send_write_mult_block(mmc, req, 1);
  357. if (ret)
  358. return ret;
  359. /*
  360. * Read the result of the request.
  361. */
  362. ret = mmc_set_blockcount(mmc, rsp_cnt, false);
  363. if (ret)
  364. return ret;
  365. return send_read_mult_block(mmc, rsp, rsp_cnt);
  366. }
  367. static int rpmb_route_frames(struct mmc *mmc, struct s_rpmb *req,
  368. unsigned short req_cnt, struct s_rpmb *rsp,
  369. unsigned short rsp_cnt)
  370. {
  371. unsigned short n;
  372. /*
  373. * If multiple request frames are provided, make sure that all are
  374. * of the same type.
  375. */
  376. for (n = 1; n < req_cnt; n++)
  377. if (req[n].request != req->request)
  378. return -EINVAL;
  379. switch (be16_to_cpu(req->request)) {
  380. case RPMB_REQ_KEY:
  381. if (req_cnt != 1 || rsp_cnt != 1)
  382. return -EINVAL;
  383. return rpmb_route_write_req(mmc, req, req_cnt, rsp, rsp_cnt);
  384. case RPMB_REQ_WRITE_DATA:
  385. if (!req_cnt || rsp_cnt != 1)
  386. return -EINVAL;
  387. return rpmb_route_write_req(mmc, req, req_cnt, rsp, rsp_cnt);
  388. case RPMB_REQ_WCOUNTER:
  389. if (req_cnt != 1 || rsp_cnt != 1)
  390. return -EINVAL;
  391. return rpmb_route_read_req(mmc, req, req_cnt, rsp, rsp_cnt);
  392. case RPMB_REQ_READ_DATA:
  393. if (req_cnt != 1 || !req_cnt)
  394. return -EINVAL;
  395. return rpmb_route_read_req(mmc, req, req_cnt, rsp, rsp_cnt);
  396. default:
  397. debug("Unsupported message type: %d\n",
  398. be16_to_cpu(req->request));
  399. return -EINVAL;
  400. }
  401. }
  402. int mmc_rpmb_route_frames(struct mmc *mmc, void *req, unsigned long reqlen,
  403. void *rsp, unsigned long rsplen)
  404. {
  405. /*
  406. * Whoever crafted the data supplied to this function knows how to
  407. * format the PRMB frames and which response is expected. If
  408. * there's some unexpected mismatch it's more helpful to report an
  409. * error immediately than trying to guess what was the intention
  410. * and possibly just delay an eventual error which will be harder
  411. * to track down.
  412. */
  413. if (reqlen % sizeof(struct s_rpmb) || rsplen % sizeof(struct s_rpmb))
  414. return -EINVAL;
  415. return rpmb_route_frames(mmc, req, reqlen / sizeof(struct s_rpmb),
  416. rsp, rsplen / sizeof(struct s_rpmb));
  417. }