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- // SPDX-License-Identifier: GPL-2.0+
- /*
- * (C) Copyright 2018 Arm Ltd.
- * (C) Copyright 2020-2021 Samuel Holland <samuel@sholland.org>
- */
- #define OPENSSL_API_COMPAT 0x10101000L
- #include <assert.h>
- #include <stdint.h>
- #include <stdio.h>
- #include <stdlib.h>
- #include <string.h>
- #include <openssl/asn1t.h>
- #include <openssl/bn.h>
- #include <openssl/pem.h>
- #include <openssl/rsa.h>
- #include <image.h>
- #include <sunxi_image.h>
- #include "imagetool.h"
- #include "mkimage.h"
- /*
- * NAND requires 8K padding. For other devices, BROM requires only
- * 512B padding, but let's use the larger padding to cover everything.
- */
- #define PAD_SIZE 8192
- #define pr_fmt(fmt) "mkimage (TOC0): %s: " fmt
- #define pr_err(fmt, args...) fprintf(stderr, pr_fmt(fmt), "error", ##args)
- #define pr_warn(fmt, args...) fprintf(stderr, pr_fmt(fmt), "warning", ##args)
- #define pr_info(fmt, args...) fprintf(stderr, pr_fmt(fmt), "info", ##args)
- #if defined(LIBRESSL_VERSION_NUMBER) && LIBRESSL_VERSION_NUMBER < 0x3050000fL
- #define RSA_get0_n(key) (key)->n
- #define RSA_get0_e(key) (key)->e
- #define RSA_get0_d(key) (key)->d
- #endif
- struct __packed toc0_key_item {
- __le32 vendor_id;
- __le32 key0_n_len;
- __le32 key0_e_len;
- __le32 key1_n_len;
- __le32 key1_e_len;
- __le32 sig_len;
- uint8_t key0[512];
- uint8_t key1[512];
- uint8_t reserved[32];
- uint8_t sig[256];
- };
- /*
- * This looks somewhat like an X.509 certificate, but it is not valid BER.
- *
- * Some differences:
- * - Some X.509 certificate fields are missing or rearranged.
- * - Some sequences have the wrong tag.
- * - Zero-length sequences are accepted.
- * - Large strings and integers must be an even number of bytes long.
- * - Positive integers are not zero-extended to maintain their sign.
- *
- * See https://linux-sunxi.org/TOC0 for more information.
- */
- struct __packed toc0_small_tag {
- uint8_t tag;
- uint8_t length;
- };
- typedef struct toc0_small_tag toc0_small_int;
- typedef struct toc0_small_tag toc0_small_oct;
- typedef struct toc0_small_tag toc0_small_seq;
- typedef struct toc0_small_tag toc0_small_exp;
- #define TOC0_SMALL_INT(len) { 0x02, (len) }
- #define TOC0_SMALL_SEQ(len) { 0x30, (len) }
- #define TOC0_SMALL_EXP(tag, len) { 0xa0 | (tag), len }
- struct __packed toc0_large_tag {
- uint8_t tag;
- uint8_t prefix;
- uint8_t length_hi;
- uint8_t length_lo;
- };
- typedef struct toc0_large_tag toc0_large_int;
- typedef struct toc0_large_tag toc0_large_bit;
- typedef struct toc0_large_tag toc0_large_seq;
- #define TOC0_LARGE_INT(len) { 0x02, 0x82, (len) >> 8, (len) & 0xff }
- #define TOC0_LARGE_BIT(len) { 0x03, 0x82, (len) >> 8, (len) & 0xff }
- #define TOC0_LARGE_SEQ(len) { 0x30, 0x82, (len) >> 8, (len) & 0xff }
- struct __packed toc0_cert_item {
- toc0_large_seq tag_totalSequence;
- struct __packed toc0_totalSequence {
- toc0_large_seq tag_mainSequence;
- struct __packed toc0_mainSequence {
- toc0_small_exp tag_explicit0;
- struct __packed toc0_explicit0 {
- toc0_small_int tag_version;
- uint8_t version;
- } explicit0;
- toc0_small_int tag_serialNumber;
- uint8_t serialNumber;
- toc0_small_seq tag_signature;
- toc0_small_seq tag_issuer;
- toc0_small_seq tag_validity;
- toc0_small_seq tag_subject;
- toc0_large_seq tag_subjectPublicKeyInfo;
- struct __packed toc0_subjectPublicKeyInfo {
- toc0_small_seq tag_algorithm;
- toc0_large_seq tag_publicKey;
- struct __packed toc0_publicKey {
- toc0_large_int tag_n;
- uint8_t n[256];
- toc0_small_int tag_e;
- uint8_t e[3];
- } publicKey;
- } subjectPublicKeyInfo;
- toc0_small_exp tag_explicit3;
- struct __packed toc0_explicit3 {
- toc0_small_seq tag_extension;
- struct __packed toc0_extension {
- toc0_small_int tag_digest;
- uint8_t digest[32];
- } extension;
- } explicit3;
- } mainSequence;
- toc0_large_bit tag_sigSequence;
- struct __packed toc0_sigSequence {
- toc0_small_seq tag_algorithm;
- toc0_large_bit tag_signature;
- uint8_t signature[256];
- } sigSequence;
- } totalSequence;
- };
- #define sizeof_field(TYPE, MEMBER) sizeof((((TYPE *)0)->MEMBER))
- static const struct toc0_cert_item cert_item_template = {
- TOC0_LARGE_SEQ(sizeof(struct toc0_totalSequence)),
- {
- TOC0_LARGE_SEQ(sizeof(struct toc0_mainSequence)),
- {
- TOC0_SMALL_EXP(0, sizeof(struct toc0_explicit0)),
- {
- TOC0_SMALL_INT(sizeof_field(struct toc0_explicit0, version)),
- 0,
- },
- TOC0_SMALL_INT(sizeof_field(struct toc0_mainSequence, serialNumber)),
- 0,
- TOC0_SMALL_SEQ(0),
- TOC0_SMALL_SEQ(0),
- TOC0_SMALL_SEQ(0),
- TOC0_SMALL_SEQ(0),
- TOC0_LARGE_SEQ(sizeof(struct toc0_subjectPublicKeyInfo)),
- {
- TOC0_SMALL_SEQ(0),
- TOC0_LARGE_SEQ(sizeof(struct toc0_publicKey)),
- {
- TOC0_LARGE_INT(sizeof_field(struct toc0_publicKey, n)),
- {},
- TOC0_SMALL_INT(sizeof_field(struct toc0_publicKey, e)),
- {},
- },
- },
- TOC0_SMALL_EXP(3, sizeof(struct toc0_explicit3)),
- {
- TOC0_SMALL_SEQ(sizeof(struct toc0_extension)),
- {
- TOC0_SMALL_INT(sizeof_field(struct toc0_extension, digest)),
- {},
- },
- },
- },
- TOC0_LARGE_BIT(sizeof(struct toc0_sigSequence)),
- {
- TOC0_SMALL_SEQ(0),
- TOC0_LARGE_BIT(sizeof_field(struct toc0_sigSequence, signature)),
- {},
- },
- },
- };
- #define TOC0_DEFAULT_NUM_ITEMS 3
- #define TOC0_DEFAULT_HEADER_LEN \
- ALIGN( \
- sizeof(struct toc0_main_info) + \
- sizeof(struct toc0_item_info) * TOC0_DEFAULT_NUM_ITEMS + \
- sizeof(struct toc0_cert_item) + \
- sizeof(struct toc0_key_item), \
- 32)
- static char *fw_key_file = "fw_key.pem";
- static char *key_item_file = "key_item.bin";
- static char *root_key_file = "root_key.pem";
- /*
- * Create a key item in @buf, containing the public keys @root_key and @fw_key,
- * and signed by the RSA key @root_key.
- */
- static int toc0_create_key_item(uint8_t *buf, uint32_t *len,
- RSA *root_key, RSA *fw_key)
- {
- struct toc0_key_item *key_item = (void *)buf;
- uint8_t digest[SHA256_DIGEST_LENGTH];
- int ret = EXIT_FAILURE;
- unsigned int sig_len;
- int n_len, e_len;
- /* Store key 0. */
- n_len = BN_bn2bin(RSA_get0_n(root_key), key_item->key0);
- e_len = BN_bn2bin(RSA_get0_e(root_key), key_item->key0 + n_len);
- if (n_len + e_len > sizeof(key_item->key0)) {
- pr_err("Root key is too big for key item\n");
- goto err;
- }
- key_item->key0_n_len = cpu_to_le32(n_len);
- key_item->key0_e_len = cpu_to_le32(e_len);
- /* Store key 1. */
- n_len = BN_bn2bin(RSA_get0_n(fw_key), key_item->key1);
- e_len = BN_bn2bin(RSA_get0_e(fw_key), key_item->key1 + n_len);
- if (n_len + e_len > sizeof(key_item->key1)) {
- pr_err("Firmware key is too big for key item\n");
- goto err;
- }
- key_item->key1_n_len = cpu_to_le32(n_len);
- key_item->key1_e_len = cpu_to_le32(e_len);
- /* Sign the key item. */
- key_item->sig_len = cpu_to_le32(RSA_size(root_key));
- SHA256(buf, key_item->sig - buf, digest);
- if (!RSA_sign(NID_sha256, digest, sizeof(digest),
- key_item->sig, &sig_len, root_key)) {
- pr_err("Failed to sign key item\n");
- goto err;
- }
- if (sig_len != sizeof(key_item->sig)) {
- pr_err("Bad key item signature length\n");
- goto err;
- }
- *len = sizeof(*key_item);
- ret = EXIT_SUCCESS;
- err:
- return ret;
- }
- /*
- * Verify the key item in @buf, containing two public keys @key0 and @key1,
- * and signed by the RSA key @key0. If @root_key is provided, only signatures
- * by that key will be accepted. @key1 is returned in @key.
- */
- static int toc0_verify_key_item(const uint8_t *buf, uint32_t len,
- RSA *root_key, RSA **fw_key)
- {
- struct toc0_key_item *key_item = (void *)buf;
- uint8_t digest[SHA256_DIGEST_LENGTH];
- int ret = EXIT_FAILURE;
- int n_len, e_len;
- RSA *key0 = NULL;
- RSA *key1 = NULL;
- BIGNUM *n, *e;
- if (len < sizeof(*key_item))
- goto err;
- /* Load key 0. */
- n_len = le32_to_cpu(key_item->key0_n_len);
- e_len = le32_to_cpu(key_item->key0_e_len);
- if (n_len + e_len > sizeof(key_item->key0)) {
- pr_err("Bad root key size in key item\n");
- goto err;
- }
- n = BN_bin2bn(key_item->key0, n_len, NULL);
- e = BN_bin2bn(key_item->key0 + n_len, e_len, NULL);
- key0 = RSA_new();
- if (!key0)
- goto err;
- if (!RSA_set0_key(key0, n, e, NULL))
- goto err;
- /* If a root key was provided, compare it to key 0. */
- if (root_key && (BN_cmp(n, RSA_get0_n(root_key)) ||
- BN_cmp(e, RSA_get0_e(root_key)))) {
- pr_err("Wrong root key in key item\n");
- goto err;
- }
- /* Verify the key item signature. */
- SHA256(buf, key_item->sig - buf, digest);
- if (!RSA_verify(NID_sha256, digest, sizeof(digest),
- key_item->sig, le32_to_cpu(key_item->sig_len), key0)) {
- pr_err("Bad key item signature\n");
- goto err;
- }
- if (fw_key) {
- /* Load key 1. */
- n_len = le32_to_cpu(key_item->key1_n_len);
- e_len = le32_to_cpu(key_item->key1_e_len);
- if (n_len + e_len > sizeof(key_item->key1)) {
- pr_err("Bad firmware key size in key item\n");
- goto err;
- }
- n = BN_bin2bn(key_item->key1, n_len, NULL);
- e = BN_bin2bn(key_item->key1 + n_len, e_len, NULL);
- key1 = RSA_new();
- if (!key1)
- goto err;
- if (!RSA_set0_key(key1, n, e, NULL))
- goto err;
- if (*fw_key) {
- /* If a FW key was provided, compare it to key 1. */
- if (BN_cmp(n, RSA_get0_n(*fw_key)) ||
- BN_cmp(e, RSA_get0_e(*fw_key))) {
- pr_err("Wrong firmware key in key item\n");
- goto err;
- }
- } else {
- /* Otherwise, send key1 back to the caller. */
- *fw_key = key1;
- key1 = NULL;
- }
- }
- ret = EXIT_SUCCESS;
- err:
- RSA_free(key0);
- RSA_free(key1);
- return ret;
- }
- /*
- * Create a certificate in @buf, describing the firmware with SHA256 digest
- * @digest, and signed by the RSA key @fw_key.
- */
- static int toc0_create_cert_item(uint8_t *buf, uint32_t *len, RSA *fw_key,
- uint8_t digest[static SHA256_DIGEST_LENGTH])
- {
- struct toc0_cert_item *cert_item = (void *)buf;
- uint8_t cert_digest[SHA256_DIGEST_LENGTH];
- struct toc0_totalSequence *totalSequence;
- struct toc0_sigSequence *sigSequence;
- struct toc0_extension *extension;
- struct toc0_publicKey *publicKey;
- int ret = EXIT_FAILURE;
- unsigned int sig_len;
- memcpy(cert_item, &cert_item_template, sizeof(*cert_item));
- *len = sizeof(*cert_item);
- /*
- * Fill in the public key.
- *
- * Only 2048-bit RSA keys are supported. Since this uses a fixed-size
- * structure, it may fail for non-standard exponents.
- */
- totalSequence = &cert_item->totalSequence;
- publicKey = &totalSequence->mainSequence.subjectPublicKeyInfo.publicKey;
- if (BN_bn2binpad(RSA_get0_n(fw_key), publicKey->n, sizeof(publicKey->n)) < 0 ||
- BN_bn2binpad(RSA_get0_e(fw_key), publicKey->e, sizeof(publicKey->e)) < 0) {
- pr_err("Firmware key is too big for certificate\n");
- goto err;
- }
- /* Fill in the firmware digest. */
- extension = &totalSequence->mainSequence.explicit3.extension;
- memcpy(&extension->digest, digest, SHA256_DIGEST_LENGTH);
- /*
- * Sign the certificate.
- *
- * In older SBROM versions (and by default in newer versions),
- * the last 4 bytes of the certificate are not signed.
- *
- * (The buffer passed to SHA256 starts at tag_mainSequence, but
- * the buffer size does not include the length of that tag.)
- */
- SHA256((uint8_t *)totalSequence, sizeof(struct toc0_mainSequence), cert_digest);
- sigSequence = &totalSequence->sigSequence;
- if (!RSA_sign(NID_sha256, cert_digest, SHA256_DIGEST_LENGTH,
- sigSequence->signature, &sig_len, fw_key)) {
- pr_err("Failed to sign certificate\n");
- goto err;
- }
- if (sig_len != sizeof(sigSequence->signature)) {
- pr_err("Bad certificate signature length\n");
- goto err;
- }
- ret = EXIT_SUCCESS;
- err:
- return ret;
- }
- /*
- * Verify the certificate in @buf, describing the firmware with SHA256 digest
- * @digest, and signed by the RSA key contained within. If @fw_key is provided,
- * only that key will be accepted.
- *
- * This function is only expected to work with images created by mkimage.
- */
- static int toc0_verify_cert_item(const uint8_t *buf, uint32_t len, RSA *fw_key,
- uint8_t digest[static SHA256_DIGEST_LENGTH])
- {
- const struct toc0_cert_item *cert_item = (const void *)buf;
- uint8_t cert_digest[SHA256_DIGEST_LENGTH];
- const struct toc0_totalSequence *totalSequence;
- const struct toc0_sigSequence *sigSequence;
- const struct toc0_extension *extension;
- const struct toc0_publicKey *publicKey;
- int ret = EXIT_FAILURE;
- RSA *key = NULL;
- BIGNUM *n, *e;
- /* Extract the public key from the certificate. */
- totalSequence = &cert_item->totalSequence;
- publicKey = &totalSequence->mainSequence.subjectPublicKeyInfo.publicKey;
- n = BN_bin2bn(publicKey->n, sizeof(publicKey->n), NULL);
- e = BN_bin2bn(publicKey->e, sizeof(publicKey->e), NULL);
- key = RSA_new();
- if (!key)
- goto err;
- if (!RSA_set0_key(key, n, e, NULL))
- goto err;
- /* If a key was provided, compare it to the embedded key. */
- if (fw_key && (BN_cmp(RSA_get0_n(key), RSA_get0_n(fw_key)) ||
- BN_cmp(RSA_get0_e(key), RSA_get0_e(fw_key)))) {
- pr_err("Wrong firmware key in certificate\n");
- goto err;
- }
- /* If a digest was provided, compare it to the embedded digest. */
- extension = &totalSequence->mainSequence.explicit3.extension;
- if (digest && memcmp(&extension->digest, digest, SHA256_DIGEST_LENGTH)) {
- pr_err("Wrong firmware digest in certificate\n");
- goto err;
- }
- /* Verify the certificate's signature. See the comment above. */
- SHA256((uint8_t *)totalSequence, sizeof(struct toc0_mainSequence), cert_digest);
- sigSequence = &totalSequence->sigSequence;
- if (!RSA_verify(NID_sha256, cert_digest, SHA256_DIGEST_LENGTH,
- sigSequence->signature,
- sizeof(sigSequence->signature), key)) {
- pr_err("Bad certificate signature\n");
- goto err;
- }
- ret = EXIT_SUCCESS;
- err:
- RSA_free(key);
- return ret;
- }
- /*
- * Always create a TOC0 containing 3 items. The extra item will be ignored on
- * SoCs which do not support it.
- */
- static int toc0_create(uint8_t *buf, uint32_t len, RSA *root_key, RSA *fw_key,
- uint8_t *key_item, uint32_t key_item_len,
- uint8_t *fw_item, uint32_t fw_item_len, uint32_t fw_addr)
- {
- struct toc0_main_info *main_info = (void *)buf;
- struct toc0_item_info *item_info = (void *)(main_info + 1);
- uint8_t digest[SHA256_DIGEST_LENGTH];
- uint32_t *buf32 = (void *)buf;
- RSA *orig_fw_key = fw_key;
- int ret = EXIT_FAILURE;
- uint32_t checksum = 0;
- uint32_t item_offset;
- uint32_t item_length;
- int i;
- /* Hash the firmware for inclusion in the certificate. */
- SHA256(fw_item, fw_item_len, digest);
- /* Create the main TOC0 header, containing three items. */
- memcpy(main_info->name, TOC0_MAIN_INFO_NAME, sizeof(main_info->name));
- main_info->magic = cpu_to_le32(TOC0_MAIN_INFO_MAGIC);
- main_info->checksum = cpu_to_le32(BROM_STAMP_VALUE);
- main_info->num_items = cpu_to_le32(TOC0_DEFAULT_NUM_ITEMS);
- memcpy(main_info->end, TOC0_MAIN_INFO_END, sizeof(main_info->end));
- /* The first item links the ROTPK to the signing key. */
- item_offset = sizeof(*main_info) +
- sizeof(*item_info) * TOC0_DEFAULT_NUM_ITEMS;
- /* Using an existing key item avoids needing the root private key. */
- if (key_item) {
- item_length = sizeof(*key_item);
- if (toc0_verify_key_item(key_item, item_length,
- root_key, &fw_key))
- goto err;
- memcpy(buf + item_offset, key_item, item_length);
- } else if (toc0_create_key_item(buf + item_offset, &item_length,
- root_key, fw_key)) {
- goto err;
- }
- item_info->name = cpu_to_le32(TOC0_ITEM_INFO_NAME_KEY);
- item_info->offset = cpu_to_le32(item_offset);
- item_info->length = cpu_to_le32(item_length);
- memcpy(item_info->end, TOC0_ITEM_INFO_END, sizeof(item_info->end));
- /* The second item contains a certificate signed by the firmware key. */
- item_offset = item_offset + item_length;
- if (toc0_create_cert_item(buf + item_offset, &item_length,
- fw_key, digest))
- goto err;
- item_info++;
- item_info->name = cpu_to_le32(TOC0_ITEM_INFO_NAME_CERT);
- item_info->offset = cpu_to_le32(item_offset);
- item_info->length = cpu_to_le32(item_length);
- memcpy(item_info->end, TOC0_ITEM_INFO_END, sizeof(item_info->end));
- /* The third item contains the actual boot code. */
- item_offset = ALIGN(item_offset + item_length, 32);
- item_length = fw_item_len;
- if (buf + item_offset != fw_item)
- memmove(buf + item_offset, fw_item, item_length);
- item_info++;
- item_info->name = cpu_to_le32(TOC0_ITEM_INFO_NAME_FIRMWARE);
- item_info->offset = cpu_to_le32(item_offset);
- item_info->length = cpu_to_le32(item_length);
- item_info->load_addr = cpu_to_le32(fw_addr);
- memcpy(item_info->end, TOC0_ITEM_INFO_END, sizeof(item_info->end));
- /* Pad to the required block size with 0xff to be flash-friendly. */
- item_offset = item_offset + item_length;
- item_length = ALIGN(item_offset, PAD_SIZE) - item_offset;
- memset(buf + item_offset, 0xff, item_length);
- /* Fill in the total padded file length. */
- item_offset = item_offset + item_length;
- main_info->length = cpu_to_le32(item_offset);
- /* Verify enough space was provided when creating the image. */
- assert(len >= item_offset);
- /* Calculate the checksum. Yes, it's that simple. */
- for (i = 0; i < item_offset / 4; ++i)
- checksum += le32_to_cpu(buf32[i]);
- main_info->checksum = cpu_to_le32(checksum);
- ret = EXIT_SUCCESS;
- err:
- if (fw_key != orig_fw_key)
- RSA_free(fw_key);
- return ret;
- }
- static const struct toc0_item_info *
- toc0_find_item(const struct toc0_main_info *main_info, uint32_t name,
- uint32_t *offset, uint32_t *length)
- {
- const struct toc0_item_info *item_info = (void *)(main_info + 1);
- uint32_t item_offset, item_length;
- uint32_t num_items, main_length;
- int i;
- num_items = le32_to_cpu(main_info->num_items);
- main_length = le32_to_cpu(main_info->length);
- for (i = 0; i < num_items; ++i, ++item_info) {
- if (le32_to_cpu(item_info->name) != name)
- continue;
- item_offset = le32_to_cpu(item_info->offset);
- item_length = le32_to_cpu(item_info->length);
- if (item_offset > main_length ||
- item_length > main_length - item_offset)
- continue;
- *offset = item_offset;
- *length = item_length;
- return item_info;
- }
- return NULL;
- }
- static int toc0_verify(const uint8_t *buf, uint32_t len, RSA *root_key)
- {
- const struct toc0_main_info *main_info = (void *)buf;
- const struct toc0_item_info *item_info;
- uint8_t digest[SHA256_DIGEST_LENGTH];
- uint32_t main_length = le32_to_cpu(main_info->length);
- uint32_t checksum = BROM_STAMP_VALUE;
- uint32_t *buf32 = (void *)buf;
- uint32_t length, offset;
- int ret = EXIT_FAILURE;
- RSA *fw_key = NULL;
- int i;
- if (len < main_length)
- goto err;
- /* Verify the main header. */
- if (memcmp(main_info->name, TOC0_MAIN_INFO_NAME, sizeof(main_info->name)))
- goto err;
- if (le32_to_cpu(main_info->magic) != TOC0_MAIN_INFO_MAGIC)
- goto err;
- /* Verify the checksum without modifying the buffer. */
- for (i = 0; i < main_length / 4; ++i)
- checksum += le32_to_cpu(buf32[i]);
- if (checksum != 2 * le32_to_cpu(main_info->checksum))
- goto err;
- /* The length must be at least 512 byte aligned. */
- if (main_length % 512)
- goto err;
- if (memcmp(main_info->end, TOC0_MAIN_INFO_END, sizeof(main_info->end)))
- goto err;
- /* Verify the key item if present (it is optional). */
- item_info = toc0_find_item(main_info, TOC0_ITEM_INFO_NAME_KEY,
- &offset, &length);
- if (!item_info)
- fw_key = root_key;
- else if (toc0_verify_key_item(buf + offset, length, root_key, &fw_key))
- goto err;
- /* Hash the firmware to compare with the certificate. */
- item_info = toc0_find_item(main_info, TOC0_ITEM_INFO_NAME_FIRMWARE,
- &offset, &length);
- if (!item_info) {
- pr_err("Missing firmware item\n");
- goto err;
- }
- SHA256(buf + offset, length, digest);
- /* Verify the certificate item. */
- item_info = toc0_find_item(main_info, TOC0_ITEM_INFO_NAME_CERT,
- &offset, &length);
- if (!item_info) {
- pr_err("Missing certificate item\n");
- goto err;
- }
- if (toc0_verify_cert_item(buf + offset, length, fw_key, digest))
- goto err;
- ret = EXIT_SUCCESS;
- err:
- if (fw_key != root_key)
- RSA_free(fw_key);
- return ret;
- }
- static int toc0_check_params(struct image_tool_params *params)
- {
- if (!params->dflag)
- return -EINVAL;
- /*
- * If a key directory was provided, look for key files there.
- * Otherwise, look for them in the current directory. The key files are
- * the "quoted" terms in the description below.
- *
- * A summary of the chain of trust on most SoCs:
- * 1) eFuse contains a SHA256 digest of the public "root key".
- * 2) Private "root key" signs the certificate item (generated here).
- * 3) Certificate item contains a SHA256 digest of the firmware item.
- *
- * A summary of the chain of trust on the H6 (by default; a bit in the
- * BROM_CONFIG eFuse makes it work like above):
- * 1) eFuse contains a SHA256 digest of the public "root key".
- * 2) Private "root key" signs the "key item" (generated here).
- * 3) "Key item" contains the public "root key" and public "fw key".
- * 4) Private "fw key" signs the certificate item (generated here).
- * 5) Certificate item contains a SHA256 digest of the firmware item.
- *
- * This means there are three valid ways to generate a TOC0:
- * 1) Provide the private "root key" only. This works everywhere.
- * For H6, the "root key" will also be used as the "fw key".
- * 2) FOR H6 ONLY: Provide the private "root key" and a separate
- * private "fw key".
- * 3) FOR H6 ONLY: Provide the private "fw key" and a pre-existing
- * "key item" containing the corresponding public "fw key".
- * In this case, the private "root key" can be kept offline. The
- * "key item" can be extracted from a TOC0 image generated using
- * method #2 above.
- *
- * Note that until the ROTPK_HASH eFuse is programmed, any "root key"
- * will be accepted by the BROM.
- */
- if (params->keydir) {
- if (asprintf(&fw_key_file, "%s/%s", params->keydir, fw_key_file) < 0)
- return -ENOMEM;
- if (asprintf(&key_item_file, "%s/%s", params->keydir, key_item_file) < 0)
- return -ENOMEM;
- if (asprintf(&root_key_file, "%s/%s", params->keydir, root_key_file) < 0)
- return -ENOMEM;
- }
- return 0;
- }
- static int toc0_verify_header(unsigned char *buf, int image_size,
- struct image_tool_params *params)
- {
- int ret = EXIT_FAILURE;
- RSA *root_key = NULL;
- FILE *fp;
- /* A root public key is optional. */
- fp = fopen(root_key_file, "rb");
- if (fp) {
- pr_info("Verifying image with existing root key\n");
- root_key = PEM_read_RSAPrivateKey(fp, NULL, NULL, NULL);
- if (!root_key)
- root_key = PEM_read_RSAPublicKey(fp, NULL, NULL, NULL);
- fclose(fp);
- if (!root_key) {
- pr_err("Failed to read public key from '%s'\n",
- root_key_file);
- goto err;
- }
- }
- ret = toc0_verify(buf, image_size, root_key);
- err:
- RSA_free(root_key);
- return ret;
- }
- static const char *toc0_item_name(uint32_t name)
- {
- if (name == TOC0_ITEM_INFO_NAME_CERT)
- return "Certificate";
- if (name == TOC0_ITEM_INFO_NAME_FIRMWARE)
- return "Firmware";
- if (name == TOC0_ITEM_INFO_NAME_KEY)
- return "Key";
- return "(unknown)";
- }
- static void toc0_print_header(const void *buf, struct image_tool_params *params)
- {
- const struct toc0_main_info *main_info = buf;
- const struct toc0_item_info *item_info = (void *)(main_info + 1);
- uint32_t head_length, main_length, num_items;
- uint32_t item_offset, item_length, item_name;
- int load_addr = -1;
- int i;
- num_items = le32_to_cpu(main_info->num_items);
- head_length = sizeof(*main_info) + num_items * sizeof(*item_info);
- main_length = le32_to_cpu(main_info->length);
- printf("Allwinner TOC0 Image\n"
- "Size: %d bytes\n"
- "Contents: %d items\n"
- " 00000000:%08x Headers\n",
- main_length, num_items, head_length);
- for (i = 0; i < num_items; ++i, ++item_info) {
- item_offset = le32_to_cpu(item_info->offset);
- item_length = le32_to_cpu(item_info->length);
- item_name = le32_to_cpu(item_info->name);
- if (item_name == TOC0_ITEM_INFO_NAME_FIRMWARE)
- load_addr = le32_to_cpu(item_info->load_addr);
- printf(" %08x:%08x %s\n",
- item_offset, item_length,
- toc0_item_name(item_name));
- }
- if (num_items && item_offset + item_length < main_length) {
- item_offset = item_offset + item_length;
- item_length = main_length - item_offset;
- printf(" %08x:%08x Padding\n",
- item_offset, item_length);
- }
- if (load_addr != -1)
- printf("Load address: 0x%08x\n", load_addr);
- }
- static void toc0_set_header(void *buf, struct stat *sbuf, int ifd,
- struct image_tool_params *params)
- {
- uint32_t key_item_len = 0;
- uint8_t *key_item = NULL;
- int ret = EXIT_FAILURE;
- RSA *root_key = NULL;
- RSA *fw_key = NULL;
- FILE *fp;
- /* Either a key item or the root private key is required. */
- fp = fopen(key_item_file, "rb");
- if (fp) {
- pr_info("Creating image using existing key item\n");
- key_item_len = sizeof(struct toc0_key_item);
- key_item = OPENSSL_malloc(key_item_len);
- if (!key_item || fread(key_item, key_item_len, 1, fp) != 1) {
- pr_err("Failed to read key item from '%s'\n",
- root_key_file);
- goto err;
- }
- fclose(fp);
- fp = NULL;
- }
- fp = fopen(root_key_file, "rb");
- if (fp) {
- root_key = PEM_read_RSAPrivateKey(fp, NULL, NULL, NULL);
- if (!root_key)
- root_key = PEM_read_RSAPublicKey(fp, NULL, NULL, NULL);
- fclose(fp);
- fp = NULL;
- }
- /* When using an existing key item, the root key is optional. */
- if (!key_item && (!root_key || !RSA_get0_d(root_key))) {
- pr_err("Failed to read private key from '%s'\n",
- root_key_file);
- pr_info("Try 'openssl genrsa -out root_key.pem'\n");
- goto err;
- }
- /* The certificate/firmware private key is always required. */
- fp = fopen(fw_key_file, "rb");
- if (fp) {
- fw_key = PEM_read_RSAPrivateKey(fp, NULL, NULL, NULL);
- fclose(fp);
- fp = NULL;
- }
- if (!fw_key) {
- /* If the root key is a private key, it can be used instead. */
- if (root_key && RSA_get0_d(root_key)) {
- pr_info("Using root key as firmware key\n");
- fw_key = root_key;
- } else {
- pr_err("Failed to read private key from '%s'\n",
- fw_key_file);
- goto err;
- }
- }
- /* Warn about potential compatibility issues. */
- if (key_item || fw_key != root_key)
- pr_warn("Only H6 supports separate root and firmware keys\n");
- ret = toc0_create(buf, params->file_size, root_key, fw_key,
- key_item, key_item_len,
- buf + TOC0_DEFAULT_HEADER_LEN,
- params->orig_file_size, params->addr);
- err:
- OPENSSL_free(key_item);
- OPENSSL_free(root_key);
- if (fw_key != root_key)
- OPENSSL_free(fw_key);
- if (fp)
- fclose(fp);
- if (ret != EXIT_SUCCESS)
- exit(ret);
- }
- static int toc0_check_image_type(uint8_t type)
- {
- return type == IH_TYPE_SUNXI_TOC0 ? 0 : 1;
- }
- static int toc0_vrec_header(struct image_tool_params *params,
- struct image_type_params *tparams)
- {
- tparams->hdr = calloc(tparams->header_size, 1);
- /* Save off the unpadded data size for SHA256 calculation. */
- params->orig_file_size = params->file_size - TOC0_DEFAULT_HEADER_LEN;
- /* Return padding to 8K blocks. */
- return ALIGN(params->file_size, PAD_SIZE) - params->file_size;
- }
- U_BOOT_IMAGE_TYPE(
- sunxi_toc0,
- "Allwinner TOC0 Boot Image support",
- TOC0_DEFAULT_HEADER_LEN,
- NULL,
- toc0_check_params,
- toc0_verify_header,
- toc0_print_header,
- toc0_set_header,
- NULL,
- toc0_check_image_type,
- NULL,
- toc0_vrec_header
- );
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