From 18b4ae2a65053f064af3fd97fd32de59aef1b6d7 Mon Sep 17 00:00:00 2001 From: Supreet Deshpande Date: Mon, 9 Nov 2020 04:58:19 +0530 Subject: [PATCH] Secure Boot V2: Fix an issue leading to manual enablement of Secure Boot v2. Fixes https://github.com/espressif/esp-idf/issues/6050 --- .../src/esp32/secure_boot.c | 54 ++++++++++++++----- 1 file changed, 40 insertions(+), 14 deletions(-) diff --git a/components/bootloader_support/src/esp32/secure_boot.c b/components/bootloader_support/src/esp32/secure_boot.c index 853d54af14..411c4cf38f 100644 --- a/components/bootloader_support/src/esp32/secure_boot.c +++ b/components/bootloader_support/src/esp32/secure_boot.c @@ -319,16 +319,26 @@ esp_err_t esp_secure_boot_v2_permanently_enable(const esp_image_metadata_t *imag uint32_t dis_reg = REG_READ(EFUSE_BLK0_RDATA0_REG); bool efuse_key_read_protected = dis_reg & EFUSE_RD_DIS_BLK2; bool efuse_key_write_protected = dis_reg & EFUSE_WR_DIS_BLK2; - if (efuse_key_write_protected == false - && efuse_key_read_protected == false - && REG_READ(EFUSE_BLK2_RDATA0_REG) == 0 - && REG_READ(EFUSE_BLK2_RDATA1_REG) == 0 - && REG_READ(EFUSE_BLK2_RDATA2_REG) == 0 - && REG_READ(EFUSE_BLK2_RDATA3_REG) == 0 - && REG_READ(EFUSE_BLK2_RDATA4_REG) == 0 - && REG_READ(EFUSE_BLK2_RDATA5_REG) == 0 - && REG_READ(EFUSE_BLK2_RDATA6_REG) == 0 - && REG_READ(EFUSE_BLK2_RDATA7_REG) == 0) { + uint32_t efuse_blk2_r0, efuse_blk2_r1, efuse_blk2_r2, efuse_blk2_r3, efuse_blk2_r4, efuse_blk2_r5, efuse_blk2_r6, efuse_blk2_r7; + efuse_blk2_r0 = REG_READ(EFUSE_BLK2_RDATA0_REG); + efuse_blk2_r1 = REG_READ(EFUSE_BLK2_RDATA1_REG); + efuse_blk2_r2 = REG_READ(EFUSE_BLK2_RDATA2_REG); + efuse_blk2_r3 = REG_READ(EFUSE_BLK2_RDATA3_REG); + efuse_blk2_r4 = REG_READ(EFUSE_BLK2_RDATA4_REG); + efuse_blk2_r5 = REG_READ(EFUSE_BLK2_RDATA5_REG); + efuse_blk2_r6 = REG_READ(EFUSE_BLK2_RDATA6_REG); + efuse_blk2_r7 = REG_READ(EFUSE_BLK2_RDATA7_REG); + + if (efuse_key_read_protected == true) { + ESP_LOGE(TAG, "Secure Boot v2 digest(BLK2) read protected, aborting...."); + return ESP_FAIL; + } + + if (efuse_key_write_protected == false + && efuse_blk2_r0 == 0 && efuse_blk2_r1 == 0 + && efuse_blk2_r2 == 0 && efuse_blk2_r3 == 0 + && efuse_blk2_r4 == 0 && efuse_blk2_r5 == 0 + && efuse_blk2_r6 == 0 && efuse_blk2_r7 == 0) { /* Verifies the signature block appended to the image matches with the signature block of the app to be loaded */ ret = secure_boot_v2_digest_generate(bootloader_data.start_addr, bootloader_data.image_len - SIG_BLOCK_PADDING, boot_pub_key_digest); if (ret != ESP_OK) { @@ -343,14 +353,30 @@ esp_err_t esp_secure_boot_v2_permanently_enable(const esp_image_metadata_t *imag ESP_LOGD(TAG, "EFUSE_BLKx_WDATA%d_REG = 0x%08x", i, boot_public_key_digest_ptr[i]); } - ESP_LOGI(TAG, "Write protecting public key digest..."); - new_wdata0 |= EFUSE_WR_DIS_BLK2; - efuse_key_write_protected = true; - efuse_key_read_protected = false; } else { + uint32_t efuse_blk2_digest[8]; + efuse_blk2_digest[0] = efuse_blk2_r0; + efuse_blk2_digest[1] = efuse_blk2_r1; + efuse_blk2_digest[2] = efuse_blk2_r2; + efuse_blk2_digest[3] = efuse_blk2_r3; + efuse_blk2_digest[4] = efuse_blk2_r4; + efuse_blk2_digest[5] = efuse_blk2_r5; + efuse_blk2_digest[6] = efuse_blk2_r6; + efuse_blk2_digest[7] = efuse_blk2_r7; + memcpy(boot_pub_key_digest, efuse_blk2_digest, DIGEST_LEN); ESP_LOGW(TAG, "Using pre-loaded secure boot v2 public key digest in EFUSE block 2"); } + if (efuse_key_write_protected == false) { + ESP_LOGI(TAG, "Write protecting public key digest..."); + ret = esp_efuse_set_write_protect(EFUSE_BLK2); + if (ret != ESP_OK) { + ESP_LOGE(TAG, "Write protecting public key digest...failed."); + return ret; + } + efuse_key_write_protected = true; + } + uint8_t app_pub_key_digest[DIGEST_LEN]; ret = secure_boot_v2_digest_generate(image_data->start_addr, image_data->image_len - SIG_BLOCK_PADDING, app_pub_key_digest); if (ret != ESP_OK) {