board/xilinx/zynq/cmds.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2018 Xilinx, Inc.
   4  */
   5
   6 #include <common.h>
   7 #include <asm/io.h>
   8 #include <asm/arch/hardware.h>
   9 #include <asm/arch/sys_proto.h>
  10 #include <malloc.h>
  11 #include <u-boot/md5.h>
  12 #include <u-boot/rsa.h>
  13 #include <u-boot/rsa-mod-exp.h>
  14 #include <u-boot/sha256.h>
  15 #include <zynqpl.h>
  16 #include <fpga.h>
  17 #include <zynq_bootimg.h>
  18
  19 DECLARE_GLOBAL_DATA_PTR;
  20
  21 #ifdef CONFIG_CMD_ZYNQ_RSA
  22
  23 #define ZYNQ_EFUSE_RSA_ENABLE_MASK      0x400
  24 #define ZYNQ_ATTRIBUTE_PL_IMAGE_MASK            0x20
  25 #define ZYNQ_ATTRIBUTE_CHECKSUM_TYPE_MASK       0x7000
  26 #define ZYNQ_ATTRIBUTE_RSA_PRESENT_MASK         0x8000
  27 #define ZYNQ_ATTRIBUTE_RSA_PART_OWNER_MASK      0x30000
  28
  29 #define ZYNQ_RSA_MODULAR_SIZE                   256
  30 #define ZYNQ_RSA_MODULAR_EXT_SIZE               256
  31 #define ZYNQ_RSA_EXPO_SIZE                      64
  32 #define ZYNQ_RSA_SPK_SIGNATURE_SIZE             256
  33 #define ZYNQ_RSA_PARTITION_SIGNATURE_SIZE       256
  34 #define ZYNQ_RSA_SIGNATURE_SIZE                 0x6C0
  35 #define ZYNQ_RSA_HEADER_SIZE                    4
  36 #define ZYNQ_RSA_MAGIC_WORD_SIZE                60
  37 #define ZYNQ_RSA_PART_OWNER_UBOOT               1
  38 #define ZYNQ_RSA_ALIGN_PPK_START                64
  39
  40 #define WORD_LENGTH_SHIFT       2
  41
  42 static u8 *ppkmodular;
  43 static u8 *ppkmodularex;
  44
  45 struct zynq_rsa_public_key {
  46         uint len;               /* Length of modulus[] in number of u32 */
  47         u32 n0inv;              /* -1 / modulus[0] mod 2^32 */
  48         u32 *modulus;   /* modulus as little endian array */
  49         u32 *rr;                /* R^2 as little endian array */
  50 };
  51
  52 static struct zynq_rsa_public_key public_key;
  53
  54 static struct partition_hdr part_hdr[ZYNQ_MAX_PARTITION_NUMBER];
  55
  56 /*
  57  * Extract the primary public key components from already autheticated FSBL
  58  */
  59 static void zynq_extract_ppk(u32 fsbl_len)
  60 {
  61         u32 padsize;
  62         u8 *ppkptr;
  63
  64         debug("%s\n", __func__);
  65
  66         /*
  67          * Extract the authenticated PPK from OCM i.e at end of the FSBL
  68          */
  69         ppkptr = (u8 *)(fsbl_len + ZYNQ_OCM_BASEADDR);
  70         padsize = ((u32)ppkptr % ZYNQ_RSA_ALIGN_PPK_START);
  71         if (padsize)
  72                 ppkptr += (ZYNQ_RSA_ALIGN_PPK_START - padsize);
  73
  74         ppkptr += ZYNQ_RSA_HEADER_SIZE;
  75
  76         ppkptr += ZYNQ_RSA_MAGIC_WORD_SIZE;
  77
  78         ppkmodular = (u8 *)ppkptr;
  79         ppkptr += ZYNQ_RSA_MODULAR_SIZE;
  80         ppkmodularex = (u8 *)ppkptr;
  81         ppkptr += ZYNQ_RSA_MODULAR_EXT_SIZE;
  82 }
  83
  84 /*
  85  * Calculate the inverse(-1 / modulus[0] mod 2^32 ) for the PPK
  86  */
  87 static u32 zynq_calc_inv(void)
  88 {
  89         u32 modulus = public_key.modulus[0];
  90         u32 tmp = BIT(1);
  91         u32 inverse;
  92
  93         inverse = modulus & BIT(0);
  94
  95         while (tmp) {
  96                 inverse *= 2 - modulus * inverse;
  97                 tmp *= tmp;
  98         }
  99
 100         return ~(inverse - 1);
 101 }
 102
 103 /*
 104  * Recreate the signature by padding the bytes and verify with hash value
 105  */
 106 static int zynq_pad_and_check(u8 *signature, u8 *hash)
 107 {
 108         u8 padding[] = {0x30, 0x31, 0x30, 0x0D, 0x06, 0x09, 0x60, 0x86, 0x48,
 109                         0x01, 0x65, 0x03, 0x04, 0x02, 0x01, 0x05, 0x00, 0x04,
 110                         0x20};
 111         u8 *pad_ptr = signature + 256;
 112         u32 pad = 202;
 113         u32 ii;
 114
 115         /*
 116          * Re-Create PKCS#1v1.5 Padding
 117          * MSB  ----------------------------------------------------LSB
 118          * 0x0 || 0x1 || 0xFF(for 202 bytes) || 0x0 || T_padding || SHA256 Hash
 119          */
 120         if (*--pad_ptr != 0 || *--pad_ptr != 1)
 121                 return -1;
 122
 123         for (ii = 0; ii < pad; ii++) {
 124                 if (*--pad_ptr != 0xFF)
 125                         return -1;
 126         }
 127
 128         if (*--pad_ptr != 0)
 129                 return -1;
 130
 131         for (ii = 0; ii < sizeof(padding); ii++) {
 132                 if (*--pad_ptr != padding[ii])
 133                         return -1;
 134         }
 135
 136         for (ii = 0; ii < 32; ii++) {
 137                 if (*--pad_ptr != hash[ii])
 138                         return -1;
 139         }
 140         return 0;
 141 }
 142
 143 /*
 144  * Verify and extract the hash value from signature using the public key
 145  * and compare it with calculated hash value.
 146  */
 147 static int zynq_rsa_verify_key(const struct zynq_rsa_public_key *key,
 148                                const u8 *sig, const u32 sig_len, const u8 *hash)
 149 {
 150         int status;
 151         void *buf;
 152
 153         if (!key || !sig || !hash)
 154                 return -1;
 155
 156         if (sig_len != (key->len * sizeof(u32))) {
 157                 printf("Signature is of incorrect length %d\n", sig_len);
 158                 return -1;
 159         }
 160
 161         /* Sanity check for stack size */
 162         if (sig_len > ZYNQ_RSA_SPK_SIGNATURE_SIZE) {
 163                 printf("Signature length %u exceeds maximum %d\n", sig_len,
 164                        ZYNQ_RSA_SPK_SIGNATURE_SIZE);
 165                 return -1;
 166         }
 167
 168         buf = malloc(sig_len);
 169         if (!buf)
 170                 return -1;
 171
 172         memcpy(buf, sig, sig_len);
 173
 174         status = zynq_pow_mod((u32 *)key, (u32 *)buf);
 175         if (status == -1) {
 176                 free(buf);
 177                 return status;
 178         }
 179
 180         status = zynq_pad_and_check((u8 *)buf, (u8 *)hash);
 181
 182         free(buf);
 183         return status;
 184 }
 185
 186 /*
 187  * Authenticate the partition
 188  */
 189 static int zynq_authenticate_part(u8 *buffer, u32 size)
 190 {
 191         u8 hash_signature[32];
 192         u8 *spk_modular;
 193         u8 *spk_modular_ex;
 194         u8 *signature_ptr;
 195         u32 status;
 196
 197         debug("%s\n", __func__);
 198
 199         signature_ptr = (u8 *)(buffer + size - ZYNQ_RSA_SIGNATURE_SIZE);
 200
 201         signature_ptr += ZYNQ_RSA_HEADER_SIZE;
 202
 203         signature_ptr += ZYNQ_RSA_MAGIC_WORD_SIZE;
 204
 205         ppkmodular = (u8 *)signature_ptr;
 206         signature_ptr += ZYNQ_RSA_MODULAR_SIZE;
 207         ppkmodularex = signature_ptr;
 208         signature_ptr += ZYNQ_RSA_MODULAR_EXT_SIZE;
 209         signature_ptr += ZYNQ_RSA_EXPO_SIZE;
 210
 211         sha256_csum_wd((const unsigned char *)signature_ptr,
 212                        (ZYNQ_RSA_MODULAR_EXT_SIZE + ZYNQ_RSA_EXPO_SIZE +
 213                        ZYNQ_RSA_MODULAR_SIZE),
 214                        (unsigned char *)hash_signature, 0x1000);
 215
 216         spk_modular = (u8 *)signature_ptr;
 217         signature_ptr += ZYNQ_RSA_MODULAR_SIZE;
 218         spk_modular_ex = (u8 *)signature_ptr;
 219         signature_ptr += ZYNQ_RSA_MODULAR_EXT_SIZE;
 220         signature_ptr += ZYNQ_RSA_EXPO_SIZE;
 221
 222         public_key.len = ZYNQ_RSA_MODULAR_SIZE / sizeof(u32);
 223         public_key.modulus = (u32 *)ppkmodular;
 224         public_key.rr = (u32 *)ppkmodularex;
 225         public_key.n0inv = zynq_calc_inv();
 226
 227         status = zynq_rsa_verify_key(&public_key, signature_ptr,
 228                                      ZYNQ_RSA_SPK_SIGNATURE_SIZE,
 229                                      hash_signature);
 230         if (status)
 231                 return status;
 232
 233         signature_ptr += ZYNQ_RSA_SPK_SIGNATURE_SIZE;
 234
 235         sha256_csum_wd((const unsigned char *)buffer,
 236                        (size - ZYNQ_RSA_PARTITION_SIGNATURE_SIZE),
 237                        (unsigned char *)hash_signature, 0x1000);
 238
 239         public_key.len = ZYNQ_RSA_MODULAR_SIZE / sizeof(u32);
 240         public_key.modulus = (u32 *)spk_modular;
 241         public_key.rr = (u32 *)spk_modular_ex;
 242         public_key.n0inv = zynq_calc_inv();
 243
 244         return zynq_rsa_verify_key(&public_key, (u8 *)signature_ptr,
 245                                    ZYNQ_RSA_PARTITION_SIGNATURE_SIZE,
 246                                    (u8 *)hash_signature);
 247 }
 248
 249 /*
 250  * Parses the partition header and verfies the authenticated and
 251  * encrypted image.
 252  */
 253 static int zynq_verify_image(u32 src_ptr)
 254 {
 255         u32 silicon_ver, image_base_addr, status;
 256         u32 partition_num = 0;
 257         u32 efuseval, srcaddr, size, fsbl_len;
 258         struct partition_hdr *hdr_ptr;
 259         u32 part_data_len, part_img_len, part_attr;
 260         u32 part_load_addr, part_dst_addr, part_chksum_offset;
 261         u32 part_start_addr, part_total_size, partitioncount;
 262         bool encrypt_part_flag = false;
 263         bool part_chksum_flag = false;
 264         bool signed_part_flag = false;
 265
 266         image_base_addr = src_ptr;
 267
 268         silicon_ver = zynq_get_silicon_version();
 269
 270         /* RSA not supported in silicon versions 1.0 and 2.0 */
 271         if (silicon_ver == 0 || silicon_ver == 1)
 272                 return -1;
 273
 274         zynq_get_partition_info(image_base_addr, &fsbl_len,
 275                                 &part_hdr[0]);
 276
 277         /* Extract ppk if efuse was blown Otherwise return error */
 278         efuseval = readl(&efuse_base->status);
 279         if (!(efuseval & ZYNQ_EFUSE_RSA_ENABLE_MASK))
 280                 return -1;
 281
 282         zynq_extract_ppk(fsbl_len);
 283
 284         partitioncount = zynq_get_part_count(&part_hdr[0]);
 285
 286         /*
 287          * As the first two partitions are related to fsbl,
 288          * we can ignore those two in bootimage and the below
 289          * code doesn't need to validate it as fsbl is already
 290          * done by now
 291          */
 292         if (partitioncount <= 2 ||
 293             partitioncount > ZYNQ_MAX_PARTITION_NUMBER)
 294                 return -1;
 295
 296         while (partition_num < partitioncount) {
 297                 if (((part_hdr[partition_num].partitionattr &
 298                    ZYNQ_ATTRIBUTE_RSA_PART_OWNER_MASK) >> 16) !=
 299                    ZYNQ_RSA_PART_OWNER_UBOOT) {
 300                         printf("UBOOT is not Owner for partition %d\n",
 301                                partition_num);
 302                         partition_num++;
 303                         continue;
 304                 }
 305                 hdr_ptr = &part_hdr[partition_num];
 306                 status = zynq_validate_hdr(hdr_ptr);
 307                 if (status)
 308                         return status;
 309
 310                 part_data_len = hdr_ptr->datawordlen;
 311                 part_img_len = hdr_ptr->imagewordlen;
 312                 part_attr = hdr_ptr->partitionattr;
 313                 part_load_addr = hdr_ptr->loadaddr;
 314                 part_chksum_offset = hdr_ptr->checksumoffset;
 315                 part_start_addr = hdr_ptr->partitionstart;
 316                 part_total_size = hdr_ptr->partitionwordlen;
 317
 318                 if (part_data_len != part_img_len) {
 319                         debug("Encrypted\n");
 320                         encrypt_part_flag = true;
 321                 }
 322
 323                 if (part_attr & ZYNQ_ATTRIBUTE_CHECKSUM_TYPE_MASK)
 324                         part_chksum_flag = true;
 325
 326                 if (part_attr & ZYNQ_ATTRIBUTE_RSA_PRESENT_MASK) {
 327                         debug("RSA Signed\n");
 328                         signed_part_flag = true;
 329                         size = part_total_size << WORD_LENGTH_SHIFT;
 330                 } else {
 331                         size = part_img_len;
 332                 }
 333
 334                 if (!signed_part_flag && !part_chksum_flag) {
 335                         printf("Partition not signed & no chksum\n");
 336                         partition_num++;
 337                         continue;
 338                 }
 339
 340                 srcaddr = image_base_addr +
 341                           (part_start_addr << WORD_LENGTH_SHIFT);
 342
 343                 /*
 344                  * This validation is just for PS DDR.
 345                  * TODO: Update this for PL DDR check as well.
 346                  */
 347                 if (part_load_addr < gd->bd->bi_dram[0].start &&
 348                     ((part_load_addr + part_data_len) >
 349                     (gd->bd->bi_dram[0].start +
 350                      gd->bd->bi_dram[0].size))) {
 351                         printf("INVALID_LOAD_ADDRESS_FAIL\n");
 352                         return -1;
 353                 }
 354
 355                 if (part_attr & ZYNQ_ATTRIBUTE_PL_IMAGE_MASK)
 356                         part_load_addr = srcaddr;
 357                 else
 358                         memcpy((u32 *)part_load_addr, (u32 *)srcaddr,
 359                                size);
 360
 361                 if (part_chksum_flag) {
 362                         part_chksum_offset = image_base_addr +
 363                                              (part_chksum_offset <<
 364                                              WORD_LENGTH_SHIFT);
 365                         status = zynq_validate_partition(part_load_addr,
 366                                                          (part_total_size <<
 367                                                           WORD_LENGTH_SHIFT),
 368                                                          part_chksum_offset);
 369                         if (status != 0) {
 370                                 printf("PART_CHKSUM_FAIL\n");
 371                                 return -1;
 372                         }
 373                         debug("Partition Validation Done\n");
 374                 }
 375
 376                 if (signed_part_flag) {
 377                         status = zynq_authenticate_part((u8 *)part_load_addr,
 378                                                         size);
 379                         if (status != 0) {
 380                                 printf("AUTHENTICATION_FAIL\n");
 381                                 return -1;
 382                         }
 383                         debug("Authentication Done\n");
 384                 }
 385
 386                 if (encrypt_part_flag) {
 387                         debug("DECRYPTION\n");
 388
 389                         part_dst_addr = part_load_addr;
 390
 391                         if (part_attr & ZYNQ_ATTRIBUTE_PL_IMAGE_MASK) {
 392                                 partition_num++;
 393                                 continue;
 394                         }
 395
 396                         status = zynq_decrypt_load(part_load_addr,
 397                                                    part_img_len,
 398                                                    part_dst_addr,
 399                                                    part_data_len);
 400                         if (status != 0) {
 401                                 printf("DECRYPTION_FAIL\n");
 402                                 return -1;
 403                         }
 404                 }
 405                 partition_num++;
 406         }
 407
 408         return 0;
 409 }
 410
 411 static int do_zynq_rsa(cmd_tbl_t *cmdtp, int flag, int argc,
 412                        char * const argv[])
 413 {
 414         u32 src_ptr;
 415         char *endp;
 416
 417         if (argc != cmdtp->maxargs)
 418                 return CMD_RET_FAILURE;
 419
 420         src_ptr = simple_strtoul(argv[2], &endp, 16);
 421         if (*argv[2] == 0 || *endp != 0)
 422                 return CMD_RET_USAGE;
 423
 424         if (zynq_verify_image(src_ptr))
 425                 return CMD_RET_FAILURE;
 426
 427         return CMD_RET_SUCCESS;
 428 }
 429 #endif
 430
 431 #ifdef CONFIG_CMD_ZYNQ_AES
 432 static int zynq_decrypt_image(cmd_tbl_t *cmdtp, int flag, int argc,
 433                               char * const argv[])
 434 {
 435         char *endp;
 436         u32 srcaddr, srclen, dstaddr, dstlen;
 437         int status;
 438
 439         if (argc < 5 && argc > cmdtp->maxargs)
 440                 return CMD_RET_USAGE;
 441
 442         srcaddr = simple_strtoul(argv[2], &endp, 16);
 443         if (*argv[2] == 0 || *endp != 0)
 444                 return CMD_RET_USAGE;
 445         srclen = simple_strtoul(argv[3], &endp, 16);
 446         if (*argv[3] == 0 || *endp != 0)
 447                 return CMD_RET_USAGE;
 448         dstaddr = simple_strtoul(argv[4], &endp, 16);
 449         if (*argv[4] == 0 || *endp != 0)
 450                 return CMD_RET_USAGE;
 451         dstlen = simple_strtoul(argv[5], &endp, 16);
 452         if (*argv[5] == 0 || *endp != 0)
 453                 return CMD_RET_USAGE;
 454
 455         /*
 456          * Roundup source and destination lengths to
 457          * word size
 458          */
 459         if (srclen % 4)
 460                 srclen = roundup(srclen, 4);
 461         if (dstlen % 4)
 462                 dstlen = roundup(dstlen, 4);
 463
 464         status = zynq_decrypt_load(srcaddr, srclen >> 2, dstaddr, dstlen >> 2);
 465         if (status != 0)
 466                 return CMD_RET_FAILURE;
 467
 468         return CMD_RET_SUCCESS;
 469 }
 470 #endif
 471
 472 static cmd_tbl_t zynq_commands[] = {
 473 #ifdef CONFIG_CMD_ZYNQ_RSA
 474         U_BOOT_CMD_MKENT(rsa, 3, 1, do_zynq_rsa, "", ""),
 475 #endif
 476 #ifdef CONFIG_CMD_ZYNQ_AES
 477         U_BOOT_CMD_MKENT(aes, 6, 1, zynq_decrypt_image, "", ""),
 478 #endif
 479 };
 480
 481 static int do_zynq(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 482 {
 483         cmd_tbl_t *zynq_cmd;
 484         int ret;
 485
 486         if (!ARRAY_SIZE(zynq_commands)) {
 487                 puts("No zynq specific command enabled\n");
 488                 return CMD_RET_USAGE;
 489         }
 490
 491         if (argc < 2)
 492                 return CMD_RET_USAGE;
 493         zynq_cmd = find_cmd_tbl(argv[1], zynq_commands,
 494                                 ARRAY_SIZE(zynq_commands));
 495         if (!zynq_cmd)
 496                 return CMD_RET_USAGE;
 497
 498         ret = zynq_cmd->cmd(zynq_cmd, flag, argc, argv);
 499
 500         return cmd_process_error(zynq_cmd, ret);
 501 }
 502
 503 #ifdef CONFIG_SYS_LONGHELP
 504 static char zynq_help_text[] =
 505         ""
 506 #ifdef CONFIG_CMD_ZYNQ_RSA
 507         "rsa <baseaddr>  - Verifies the authenticated and encrypted\n"
 508         "                  zynq images and loads them back to load\n"
 509         "                  addresses as specified in BOOT image(BOOT.BIN)\n"
 510 #endif
 511 #ifdef CONFIG_CMD_ZYNQ_AES
 512         "aes <srcaddr> <srclen> <dstaddr> <dstlen>\n"
 513         "                - Decrypts the encrypted image present in source\n"
 514         "                  address and places the decrypted image at\n"
 515         "                  destination address\n"
 516 #endif
 517         ;
 518 #endif
 519
 520 U_BOOT_CMD(zynq,        6,      0,      do_zynq,
 521            "Zynq specific commands", zynq_help_text
 522 );