/* * Copyright (C) 2016 The Android Open Source Project * * Permission is hereby granted, free of charge, to any person * obtaining a copy of this software and associated documentation * files (the "Software"), to deal in the Software without * restriction, including without limitation the rights to use, copy, * modify, merge, publish, distribute, sublicense, and/or sell copies * of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be * included in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. */ /* Copyright (c) 2017-2019, The Linux Foundation. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are * met: * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above * copyright notice, this list of conditions and the following * disclaimer in the documentation and/or other materials provided * with the distribution. * * Neither the name of The Linux Foundation nor the names of its * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include "avb_slot_verify.h" #include "avb_chain_partition_descriptor.h" #include "avb_footer.h" #include "avb_hash_descriptor.h" #include "avb_kernel_cmdline_descriptor.h" #include "avb_sha.h" #include "avb_util.h" #include "avb_vbmeta_image.h" #include "avb_version.h" /* Maximum allow length (in bytes) of a partition name, including * ab_suffix. */ #define PART_NAME_MAX_SIZE 32 /* Maximum number of partitions that can be loaded with avb_slot_verify(). */ #define MAX_NUMBER_OF_LOADED_PARTITIONS 32 /* Maximum number of vbmeta images that can be loaded with avb_slot_verify(). */ #define MAX_NUMBER_OF_VBMETA_IMAGES 32 /* Maximum size of a vbmeta image - 64 KiB. */ #define VBMETA_MAX_SIZE (64 * 1024) /* Helper function to see if we should continue with verification in * allow_verification_error=true mode if something goes wrong. See the * comments for the avb_slot_verify() function for more information. */ static inline bool result_should_continue(AvbSlotVerifyResult result) { switch (result) { case AVB_SLOT_VERIFY_RESULT_ERROR_OOM: case AVB_SLOT_VERIFY_RESULT_ERROR_IO: case AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA: case AVB_SLOT_VERIFY_RESULT_ERROR_UNSUPPORTED_VERSION: case AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_ARGUMENT: return false; case AVB_SLOT_VERIFY_RESULT_OK: case AVB_SLOT_VERIFY_RESULT_ERROR_VERIFICATION: case AVB_SLOT_VERIFY_RESULT_ERROR_ROLLBACK_INDEX: case AVB_SLOT_VERIFY_RESULT_ERROR_PUBLIC_KEY_REJECTED: return true; } return false; } static AvbSlotVerifyResult load_and_verify_hash_partition( AvbOps* ops, const char* const* requested_partitions, const char* ab_suffix, bool allow_verification_error, const AvbDescriptor* descriptor, AvbSlotVerifyData* slot_data) { AvbHashDescriptor hash_desc; AvbSHA256Ctx sha256_ctx; AvbSHA512Ctx sha512_ctx; const uint8_t* desc_partition_name = NULL; const uint8_t* desc_salt; const uint8_t* desc_digest; char part_name[PART_NAME_MAX_SIZE]; AvbSlotVerifyResult ret; AvbIOResult io_ret; uint8_t* image_buf = NULL; size_t part_num_read; uint8_t* digest; size_t digest_len; const char* found; uint64_t image_size; if (!avb_hash_descriptor_validate_and_byteswap( (const AvbHashDescriptor*)descriptor, &hash_desc)) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; goto out; } desc_partition_name = ((const uint8_t*)descriptor) + sizeof(AvbHashDescriptor); desc_salt = desc_partition_name + hash_desc.partition_name_len; desc_digest = desc_salt + hash_desc.salt_len; if (!avb_validate_utf8(desc_partition_name, hash_desc.partition_name_len)) { avb_error("Partition name is not valid UTF-8.\n"); ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; goto out; } /* Don't bother loading or validating unless the partition was * requested in the first place. */ found = avb_strv_find_str(requested_partitions, (const char*)desc_partition_name, hash_desc.partition_name_len); if (found == NULL) { ret = AVB_SLOT_VERIFY_RESULT_OK; goto out; } if (!avb_str_concat(part_name, sizeof part_name, (const char*)desc_partition_name, hash_desc.partition_name_len, ab_suffix, avb_strlen(ab_suffix))) { avb_error("Partition name and suffix does not fit.\n"); ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; goto out; } /* If we're allowing verification errors then hash_desc.image_size * may no longer match what's in the partition... so in this case * just load the entire partition. * * For example, this can happen if a developer does 'fastboot flash * boot /path/to/new/and/bigger/boot.img'. We want this to work * since it's such a common workflow. */ image_size = hash_desc.image_size; if (allow_verification_error) { io_ret = ops->get_size_of_partition (ops, part_name, &image_size); if (io_ret == AVB_IO_RESULT_ERROR_OOM) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto out; } else if (io_ret != AVB_IO_RESULT_OK) { avb_errorv (part_name, ": Error determining partition size.\n", NULL); ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO; goto out; } avb_debugv (part_name, ": Loading entire partition.\n", NULL); } image_buf = avb_malloc(image_size); if (image_buf == NULL) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto out; } io_ret = ops->read_from_partition( ops, part_name, 0 /* offset */, image_size, image_buf, &part_num_read); if (io_ret == AVB_IO_RESULT_ERROR_OOM) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto out; } else if (io_ret != AVB_IO_RESULT_OK) { avb_errorv(part_name, ": Error loading data from partition.\n", NULL); ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO; goto out; } if (part_num_read != image_size) { avb_errorv(part_name, ": Read fewer than requested bytes.\n", NULL); ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO; goto out; } if (Avb_StrnCmp ( (CONST CHAR8*)hash_desc.hash_algorithm, "sha256", avb_strlen ("sha256")) == 0) { avb_sha256_init(&sha256_ctx); avb_sha256_update(&sha256_ctx, desc_salt, hash_desc.salt_len); avb_sha256_update(&sha256_ctx, image_buf, hash_desc.image_size); digest = avb_sha256_final(&sha256_ctx); digest_len = AVB_SHA256_DIGEST_SIZE; } else if (Avb_StrnCmp ( (CONST CHAR8*)hash_desc.hash_algorithm, "sha512", avb_strlen ("sha512")) == 0) { avb_sha512_init(&sha512_ctx); avb_sha512_update(&sha512_ctx, desc_salt, hash_desc.salt_len); avb_sha512_update(&sha512_ctx, image_buf, hash_desc.image_size); digest = avb_sha512_final(&sha512_ctx); digest_len = AVB_SHA512_DIGEST_SIZE; } else { avb_errorv(part_name, ": Unsupported hash algorithm.\n", NULL); ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; goto out; } if (digest_len != hash_desc.digest_len) { avb_errorv( part_name, ": Digest in descriptor not of expected size.\n", NULL); ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; goto out; } if (avb_safe_memcmp(digest, desc_digest, digest_len) != 0) { avb_errorv(part_name, ": Hash of data does not match digest in descriptor.\n", NULL); ret = AVB_SLOT_VERIFY_RESULT_ERROR_VERIFICATION; goto out; } else { avb_debugv (part_name, ": success: Image verification completed\n", NULL); } ret = AVB_SLOT_VERIFY_RESULT_OK; out: /* If it worked and something was loaded, copy to slot_data. */ if ((ret == AVB_SLOT_VERIFY_RESULT_OK || result_should_continue(ret)) && image_buf != NULL) { AvbPartitionData* loaded_partition; if (slot_data->num_loaded_partitions == MAX_NUMBER_OF_LOADED_PARTITIONS) { avb_errorv(part_name, ": Too many loaded partitions.\n", NULL); ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto fail; } loaded_partition = &slot_data->loaded_partitions[slot_data->num_loaded_partitions++]; loaded_partition->partition_name = avb_strdup(found); loaded_partition->data_size = image_size; loaded_partition->data = image_buf; image_buf = NULL; } fail: if (image_buf != NULL) { avb_free(image_buf); } return ret; } static AvbSlotVerifyResult load_requested_partitions( AvbOps* ops, const char* const* requested_partitions, const char* ab_suffix, AvbSlotVerifyData* slot_data) { AvbSlotVerifyResult ret; uint8_t* image_buf = NULL; size_t n; for (n = 0; requested_partitions[n] != NULL; n++) { char part_name[PART_NAME_MAX_SIZE]; AvbIOResult io_ret; uint64_t image_size; size_t part_num_read; AvbPartitionData* loaded_partition; if (!avb_str_concat(part_name, sizeof part_name, requested_partitions[n], avb_strlen(requested_partitions[n]), ab_suffix, avb_strlen(ab_suffix))) { avb_error("Partition name and suffix does not fit.\n"); ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; goto out; } io_ret = ops->get_size_of_partition(ops, part_name, &image_size); if (io_ret == AVB_IO_RESULT_ERROR_OOM) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto out; } else if (io_ret != AVB_IO_RESULT_OK) { avb_errorv(part_name, ": Error determining partition size.\n", NULL); ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO; goto out; } avb_debugv(part_name, ": Loading entire partition.\n", NULL); image_buf = avb_malloc(image_size); if (image_buf == NULL) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto out; } io_ret = ops->read_from_partition( ops, part_name, 0 /* offset */, image_size, image_buf, &part_num_read); if (io_ret == AVB_IO_RESULT_ERROR_OOM) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto out; } else if (io_ret != AVB_IO_RESULT_OK) { avb_errorv(part_name, ": Error loading data from partition.\n", NULL); ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO; goto out; } if (part_num_read != image_size) { avb_errorv(part_name, ": Read fewer than requested bytes.\n", NULL); ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO; goto out; } /* Move to slot_data. */ if (slot_data->num_loaded_partitions == MAX_NUMBER_OF_LOADED_PARTITIONS) { avb_errorv(part_name, ": Too many loaded partitions.\n", NULL); ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto out; } loaded_partition = &slot_data->loaded_partitions[slot_data->num_loaded_partitions++]; loaded_partition->partition_name = avb_strdup(requested_partitions[n]); if (loaded_partition->partition_name == NULL) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto out; } loaded_partition->data_size = image_size; loaded_partition->data = image_buf; image_buf = NULL; } ret = AVB_SLOT_VERIFY_RESULT_OK; out: if (image_buf != NULL) { avb_free(image_buf); } return ret; } static AvbSlotVerifyResult load_and_verify_vbmeta( AvbOps* ops, const char* const* requested_partitions, const char* ab_suffix, bool allow_verification_error, AvbVBMetaImageFlags toplevel_vbmeta_flags, int rollback_index_location, const char* partition_name, size_t partition_name_len, const uint8_t* expected_public_key, size_t expected_public_key_length, AvbSlotVerifyData* slot_data, AvbAlgorithmType* out_algorithm_type) { char full_partition_name[PART_NAME_MAX_SIZE]; AvbSlotVerifyResult ret; AvbIOResult io_ret; size_t vbmeta_offset; size_t vbmeta_size; uint8_t* vbmeta_buf = NULL; size_t vbmeta_num_read; AvbVBMetaVerifyResult vbmeta_ret; const uint8_t* pk_data; size_t pk_len; AvbVBMetaImageHeader vbmeta_header; uint64_t stored_rollback_index; const AvbDescriptor** descriptors = NULL; size_t num_descriptors; size_t n; bool is_main_vbmeta; bool look_for_vbmeta_footer; AvbVBMetaData* vbmeta_image_data = NULL; ret = AVB_SLOT_VERIFY_RESULT_OK; if (slot_data == NULL) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_ARGUMENT; goto out; } /* Since we allow top-level vbmeta in 'boot', use * rollback_index_location to determine whether we're the main * vbmeta struct. */ is_main_vbmeta = (rollback_index_location == 0); /* Don't use footers for vbmeta partitions ('vbmeta' or * 'vbmeta_'). */ look_for_vbmeta_footer = true; if (Avb_StrnCmp(partition_name, "vbmeta", avb_strlen("vbmeta")) == 0) { look_for_vbmeta_footer = false; } if (!avb_validate_utf8((const uint8_t*)partition_name, partition_name_len)) { avb_error("Partition name is not valid UTF-8.\n"); ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; goto out; } /* Construct full partition name e.g. system_a. */ if (!avb_str_concat(full_partition_name, sizeof full_partition_name, partition_name, partition_name_len, ab_suffix, avb_strlen(ab_suffix))) { avb_error("Partition name and suffix does not fit.\n"); ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; goto out; } /* If we're loading from the main vbmeta partition, the vbmeta struct is in * the beginning. Otherwise we may have to locate it via a footer... if no * footer is found, we look in the beginning to support e.g. vbmeta_ * partitions holding data for e.g. super partitions (b/80195851 for * rationale). */ vbmeta_offset = 0; vbmeta_size = VBMETA_MAX_SIZE; if (look_for_vbmeta_footer) { uint8_t footer_buf[AVB_FOOTER_SIZE]; size_t footer_num_read; AvbFooter footer; io_ret = ops->read_from_partition(ops, full_partition_name, -AVB_FOOTER_SIZE, AVB_FOOTER_SIZE, footer_buf, &footer_num_read); if (io_ret == AVB_IO_RESULT_ERROR_OOM) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto out; } else if (io_ret != AVB_IO_RESULT_OK) { avb_errorv(full_partition_name, ": Error loading footer.\n", NULL); ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO; goto out; } avb_assert(footer_num_read == AVB_FOOTER_SIZE); if (!avb_footer_validate_and_byteswap((const AvbFooter*)footer_buf, &footer)) { avb_debugv(full_partition_name, ": No footer detected.\n", NULL); } else { /* Basic footer sanity check since the data is untrusted. */ if (footer.vbmeta_size > VBMETA_MAX_SIZE) { avb_errorv( full_partition_name, ": Invalid vbmeta size in footer.\n", NULL); } else { vbmeta_offset = footer.vbmeta_offset; vbmeta_size = footer.vbmeta_size; } } } vbmeta_buf = avb_malloc(vbmeta_size); if (vbmeta_buf == NULL) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto out; } if (vbmeta_offset != 0) { avb_debugv("Loading vbmeta struct in footer from partition '", full_partition_name, "'.\n", NULL); } else { avb_debugv("Loading vbmeta struct from partition '", full_partition_name, "'.\n", NULL); } io_ret = ops->read_from_partition(ops, full_partition_name, vbmeta_offset, vbmeta_size, vbmeta_buf, &vbmeta_num_read); if (io_ret == AVB_IO_RESULT_ERROR_OOM) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto out; } else if (io_ret != AVB_IO_RESULT_OK) { /* If we're looking for 'vbmeta' but there is no such partition, * go try to get it from the boot partition instead. */ if (is_main_vbmeta && io_ret == AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION && !look_for_vbmeta_footer) { avb_debugv(full_partition_name, ": No such partition. Trying 'boot' instead.\n", NULL); ret = load_and_verify_vbmeta(ops, requested_partitions, ab_suffix, allow_verification_error, 0 /* toplevel_vbmeta_flags */, 0 /* rollback_index_location */, "boot", avb_strlen("boot"), NULL /* expected_public_key */, 0 /* expected_public_key_length */, slot_data, out_algorithm_type); goto out; } else { avb_errorv(full_partition_name, ": Error loading vbmeta data.\n", NULL); ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO; goto out; } } avb_assert(vbmeta_num_read <= vbmeta_size); /* Check if the image is properly signed and get the public key used * to sign the image. */ vbmeta_ret = avb_vbmeta_image_verify(vbmeta_buf, vbmeta_num_read, &pk_data, &pk_len); switch (vbmeta_ret) { case AVB_VBMETA_VERIFY_RESULT_OK: avb_assert(pk_data != NULL && pk_len > 0); break; case AVB_VBMETA_VERIFY_RESULT_OK_NOT_SIGNED: case AVB_VBMETA_VERIFY_RESULT_HASH_MISMATCH: case AVB_VBMETA_VERIFY_RESULT_SIGNATURE_MISMATCH: ret = AVB_SLOT_VERIFY_RESULT_ERROR_VERIFICATION; avb_errorv(full_partition_name, ": Error verifying vbmeta image: ", avb_vbmeta_verify_result_to_string(vbmeta_ret), "\n", NULL); if (!allow_verification_error) { goto out; } break; case AVB_VBMETA_VERIFY_RESULT_INVALID_VBMETA_HEADER: /* No way to continue this case. */ ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; avb_errorv(full_partition_name, ": Error verifying vbmeta image: invalid vbmeta header\n", NULL); goto out; case AVB_VBMETA_VERIFY_RESULT_UNSUPPORTED_VERSION: /* No way to continue this case. */ ret = AVB_SLOT_VERIFY_RESULT_ERROR_UNSUPPORTED_VERSION; avb_errorv(full_partition_name, ": Error verifying vbmeta image: unsupported AVB version\n", NULL); goto out; } /* Byteswap the header. */ avb_vbmeta_image_header_to_host_byte_order((AvbVBMetaImageHeader*)vbmeta_buf, &vbmeta_header); /* If we're the toplevel, assign flags so they'll be passed down. */ if (is_main_vbmeta) { toplevel_vbmeta_flags = (AvbVBMetaImageFlags)vbmeta_header.flags; } else { if (vbmeta_header.flags != 0) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; avb_errorv(full_partition_name, ": chained vbmeta image has non-zero flags\n", NULL); goto out; } } /* Check if key used to make signature matches what is expected. */ if (pk_data != NULL) { if (expected_public_key != NULL) { avb_assert(!is_main_vbmeta); if (expected_public_key_length != pk_len || avb_safe_memcmp(expected_public_key, pk_data, pk_len) != 0) { avb_errorv(full_partition_name, ": Public key used to sign data does not match key in chain " "partition descriptor.\n", NULL); ret = AVB_SLOT_VERIFY_RESULT_ERROR_PUBLIC_KEY_REJECTED; if (!allow_verification_error) { goto out; } } } else { bool key_is_trusted = false; const uint8_t* pk_metadata = NULL; size_t pk_metadata_len = 0; if (vbmeta_header.public_key_metadata_size > 0) { pk_metadata = vbmeta_buf + sizeof(AvbVBMetaImageHeader) + vbmeta_header.authentication_data_block_size + vbmeta_header.public_key_metadata_offset; pk_metadata_len = vbmeta_header.public_key_metadata_size; } avb_assert(is_main_vbmeta); io_ret = ops->validate_vbmeta_public_key( ops, pk_data, pk_len, pk_metadata, pk_metadata_len, &key_is_trusted); if (io_ret == AVB_IO_RESULT_ERROR_OOM) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto out; } else if (io_ret != AVB_IO_RESULT_OK) { avb_errorv(full_partition_name, ": Error while checking public key used to sign data.\n", NULL); ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO; goto out; } if (!key_is_trusted) { avb_errorv(full_partition_name, ": Public key used to sign data rejected.\n", NULL); ret = AVB_SLOT_VERIFY_RESULT_ERROR_PUBLIC_KEY_REJECTED; if (!allow_verification_error) { goto out; } } } } /* Check rollback index. */ io_ret = ops->read_rollback_index( ops, rollback_index_location, &stored_rollback_index); if (io_ret == AVB_IO_RESULT_ERROR_OOM) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto out; } else if (io_ret != AVB_IO_RESULT_OK) { avb_errorv(full_partition_name, ": Error getting rollback index for location.\n", NULL); ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO; goto out; } if (vbmeta_header.rollback_index < stored_rollback_index) { avb_errorv( full_partition_name, ": Image rollback index is less than the stored rollback index.\n", NULL); ret = AVB_SLOT_VERIFY_RESULT_ERROR_ROLLBACK_INDEX; if (!allow_verification_error) { goto out; } } if (!allow_verification_error) { if (stored_rollback_index < vbmeta_header.rollback_index) { io_ret = ops->write_rollback_index ( ops, rollback_index_location, vbmeta_header.rollback_index); if (io_ret != AVB_IO_RESULT_OK) { avb_errorv (full_partition_name, ": Error storing rollback index for location.\n", NULL); ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO; goto out; } } } /* Copy vbmeta to vbmeta_images before recursing. */ if (is_main_vbmeta) { avb_assert(slot_data->num_vbmeta_images == 0); } else { avb_assert(slot_data->num_vbmeta_images > 0); } if (slot_data->num_vbmeta_images == MAX_NUMBER_OF_VBMETA_IMAGES) { avb_errorv(full_partition_name, ": Too many vbmeta images.\n", NULL); ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto out; } vbmeta_image_data = &slot_data->vbmeta_images[slot_data->num_vbmeta_images++]; vbmeta_image_data->partition_name = avb_strdup(partition_name); vbmeta_image_data->vbmeta_data = vbmeta_buf; /* Note that |vbmeta_buf| is actually |vbmeta_num_read| bytes long * and this includes data past the end of the image. Pass the * actual size of the vbmeta image. Also, no need to use * avb_safe_add() since the header has already been verified. */ vbmeta_image_data->vbmeta_size = sizeof(AvbVBMetaImageHeader) + vbmeta_header.authentication_data_block_size + vbmeta_header.auxiliary_data_block_size; vbmeta_image_data->verify_result = vbmeta_ret; /* If verification has been disabled by setting a bit in the image, * we're done... except that we need to load the entirety of the * requested partitions. */ if (vbmeta_header.flags & AVB_VBMETA_IMAGE_FLAGS_VERIFICATION_DISABLED) { AvbSlotVerifyResult sub_ret; avb_debugv( full_partition_name, ": VERIFICATION_DISABLED bit is set.\n", NULL); /* If load_requested_partitions() fail it is always a fatal * failure (e.g. ERROR_INVALID_ARGUMENT, ERROR_OOM, etc.) rather * than recoverable (e.g. one where result_should_continue() * returns true) and we want to convey that error. */ sub_ret = load_requested_partitions( ops, requested_partitions, ab_suffix, slot_data); if (sub_ret != AVB_SLOT_VERIFY_RESULT_OK) { ret = sub_ret; } goto out; } /* Now go through all descriptors and take the appropriate action: * * - hash descriptor: Load data from partition, calculate hash, and * checks that it matches what's in the hash descriptor. * * - hashtree descriptor: Do nothing since verification happens * on-the-fly from within the OS. * * - chained partition descriptor: Load the footer, load the vbmeta * image, verify vbmeta image (includes rollback checks, hash * checks, bail on chained partitions). */ descriptors = avb_descriptor_get_all(vbmeta_buf, vbmeta_num_read, &num_descriptors); if (descriptors == NULL) { goto out; } for (n = 0; n < num_descriptors; n++) { AvbDescriptor desc; if (!avb_descriptor_validate_and_byteswap(descriptors[n], &desc)) { avb_errorv(full_partition_name, ": Descriptor is invalid.\n", NULL); ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; goto out; } switch (desc.tag) { case AVB_DESCRIPTOR_TAG_HASH: { AvbSlotVerifyResult sub_ret; sub_ret = load_and_verify_hash_partition(ops, requested_partitions, ab_suffix, allow_verification_error, descriptors[n], slot_data); if (sub_ret != AVB_SLOT_VERIFY_RESULT_OK) { ret = sub_ret; if (!allow_verification_error || !result_should_continue(ret)) { goto out; } } } break; case AVB_DESCRIPTOR_TAG_CHAIN_PARTITION: { AvbSlotVerifyResult sub_ret; AvbChainPartitionDescriptor chain_desc; const uint8_t* chain_partition_name; const uint8_t* chain_public_key; /* Only allow CHAIN_PARTITION descriptors in the main vbmeta image. */ if (!is_main_vbmeta) { avb_errorv(full_partition_name, ": Encountered chain descriptor not in main image.\n", NULL); ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; goto out; } if (!avb_chain_partition_descriptor_validate_and_byteswap( (AvbChainPartitionDescriptor*)descriptors[n], &chain_desc)) { avb_errorv(full_partition_name, ": Chain partition descriptor is invalid.\n", NULL); ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; goto out; } if (chain_desc.rollback_index_location == 0) { avb_errorv(full_partition_name, ": Chain partition has invalid " "rollback_index_location field.\n", NULL); ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; goto out; } chain_partition_name = ((const uint8_t*)descriptors[n]) + sizeof(AvbChainPartitionDescriptor); chain_public_key = chain_partition_name + chain_desc.partition_name_len; sub_ret = load_and_verify_vbmeta(ops, requested_partitions, ab_suffix, allow_verification_error, toplevel_vbmeta_flags, chain_desc.rollback_index_location, (const char*)chain_partition_name, chain_desc.partition_name_len, chain_public_key, chain_desc.public_key_len, slot_data, NULL /* out_algorithm_type */); if (sub_ret != AVB_SLOT_VERIFY_RESULT_OK) { ret = sub_ret; if (!result_should_continue(ret)) { goto out; } } } break; case AVB_DESCRIPTOR_TAG_KERNEL_CMDLINE: { const uint8_t* kernel_cmdline; AvbKernelCmdlineDescriptor kernel_cmdline_desc; bool apply_cmdline; if (!avb_kernel_cmdline_descriptor_validate_and_byteswap( (AvbKernelCmdlineDescriptor*)descriptors[n], &kernel_cmdline_desc)) { avb_errorv(full_partition_name, ": Kernel cmdline descriptor is invalid.\n", NULL); ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; goto out; } kernel_cmdline = ((const uint8_t*)descriptors[n]) + sizeof(AvbKernelCmdlineDescriptor); if (!avb_validate_utf8(kernel_cmdline, kernel_cmdline_desc.kernel_cmdline_length)) { avb_errorv(full_partition_name, ": Kernel cmdline is not valid UTF-8.\n", NULL); ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; goto out; } /* Compare the flags for top-level VBMeta struct with flags in * the command-line descriptor so command-line snippets only * intended for a certain mode (dm-verity enabled/disabled) * are skipped if applicable. */ apply_cmdline = true; if (toplevel_vbmeta_flags & AVB_VBMETA_IMAGE_FLAGS_HASHTREE_DISABLED) { if (kernel_cmdline_desc.flags & AVB_KERNEL_CMDLINE_FLAGS_USE_ONLY_IF_HASHTREE_NOT_DISABLED) { apply_cmdline = false; } } else { if (kernel_cmdline_desc.flags & AVB_KERNEL_CMDLINE_FLAGS_USE_ONLY_IF_HASHTREE_DISABLED) { apply_cmdline = false; } } if (apply_cmdline) { if (slot_data->cmdline == NULL) { slot_data->cmdline = avb_calloc(kernel_cmdline_desc.kernel_cmdline_length + 1); if (slot_data->cmdline == NULL) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto out; } avb_memcpy(slot_data->cmdline, kernel_cmdline, kernel_cmdline_desc.kernel_cmdline_length); } else { /* new cmdline is: + ' ' + + '\0' */ size_t orig_size = avb_strlen(slot_data->cmdline); size_t new_size = orig_size + 1 + kernel_cmdline_desc.kernel_cmdline_length + 1; char* new_cmdline = avb_calloc(new_size); if (new_cmdline == NULL) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto out; } avb_memcpy(new_cmdline, slot_data->cmdline, orig_size); new_cmdline[orig_size] = ' '; avb_memcpy(new_cmdline + orig_size + 1, kernel_cmdline, kernel_cmdline_desc.kernel_cmdline_length); avb_free(slot_data->cmdline); slot_data->cmdline = new_cmdline; } } } break; /* Explicit fall-through */ case AVB_DESCRIPTOR_TAG_PROPERTY: case AVB_DESCRIPTOR_TAG_HASHTREE: /* Do nothing. */ break; } } if (rollback_index_location >= AVB_MAX_NUMBER_OF_ROLLBACK_INDEX_LOCATIONS) { avb_errorv( full_partition_name, ": Invalid rollback_index_location.\n", NULL); ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; goto out; } slot_data->rollback_indexes[rollback_index_location] = vbmeta_header.rollback_index; if (out_algorithm_type != NULL) { *out_algorithm_type = (AvbAlgorithmType)vbmeta_header.algorithm_type; } out: /* If |vbmeta_image_data| isn't NULL it means that it adopted * |vbmeta_buf| so in that case don't free it here. */ if (vbmeta_image_data == NULL) { if (vbmeta_buf != NULL) { avb_free(vbmeta_buf); } } if (descriptors != NULL) { avb_free(descriptors); } return ret; } #define NUM_GUIDS 3 /* Substitutes all variables (e.g. $(ANDROID_SYSTEM_PARTUUID)) with * values. Returns NULL on OOM, otherwise the cmdline with values * replaced. */ static char* sub_cmdline(AvbOps* ops, const char* cmdline, const char* ab_suffix, bool using_boot_for_vbmeta) { const char* part_name_str[NUM_GUIDS] = {"system", "boot", "vbmeta"}; const char* replace_str[NUM_GUIDS] = {"$(ANDROID_SYSTEM_PARTUUID)", "$(ANDROID_BOOT_PARTUUID)", "$(ANDROID_VBMETA_PARTUUID)"}; char* ret = NULL; AvbIOResult io_ret; /* Special-case for when the top-level vbmeta struct is in the boot * partition. */ if (using_boot_for_vbmeta) { part_name_str[2] = "boot"; } /* Replace unique partition GUIDs */ for (size_t n = 0; n < NUM_GUIDS; n++) { char part_name[PART_NAME_MAX_SIZE]; char guid_buf[37]; /* Don't attempt to query the partition guid unless its search string is * present in the command line. Note: the original cmdline is used here, * not the replaced one. */ if (avb_strstr (cmdline, replace_str[n]) == NULL) { continue; } if (!avb_str_concat(part_name, sizeof part_name, part_name_str[n], avb_strlen(part_name_str[n]), ab_suffix, avb_strlen(ab_suffix))) { avb_error("Partition name and suffix does not fit.\n"); goto fail; } io_ret = ops->get_unique_guid_for_partition( ops, part_name, guid_buf, sizeof guid_buf); if (io_ret == AVB_IO_RESULT_ERROR_OOM) { return NULL; } else if (io_ret != AVB_IO_RESULT_OK) { avb_error("Error getting unique GUID for partition.\n"); goto fail; } if (ret == NULL) { ret = avb_replace(cmdline, replace_str[n], guid_buf); } else { char* new_ret = avb_replace(ret, replace_str[n], guid_buf); avb_free(ret); ret = new_ret; } if (ret == NULL) { goto fail; } } return ret; fail: if (ret != NULL) { avb_free(ret); } return NULL; } static int cmdline_append_option(AvbSlotVerifyData* slot_data, const char* key, const char* value) { size_t offset, key_len, value_len; char* new_cmdline; key_len = avb_strlen(key); value_len = avb_strlen(value); offset = 0; if (slot_data->cmdline != NULL) { offset = avb_strlen(slot_data->cmdline); if (offset > 0) { offset += 1; } } new_cmdline = avb_calloc(offset + key_len + value_len + 2); if (new_cmdline == NULL) { return 0; } if (offset > 0) { avb_memcpy(new_cmdline, slot_data->cmdline, offset - 1); new_cmdline[offset - 1] = ' '; } avb_memcpy(new_cmdline + offset, key, key_len); new_cmdline[offset + key_len] = '='; avb_memcpy(new_cmdline + offset + key_len + 1, value, value_len); if (slot_data->cmdline != NULL) { avb_free(slot_data->cmdline); } slot_data->cmdline = new_cmdline; return 1; } #define AVB_MAX_DIGITS_UINT64 32 /* Writes |value| to |digits| in base 10 followed by a NUL byte. * Returns number of characters written excluding the NUL byte. */ static size_t uint64_to_base10(uint64_t value, char digits[AVB_MAX_DIGITS_UINT64]) { char rev_digits[AVB_MAX_DIGITS_UINT64]; size_t n, num_digits; for (num_digits = 0; num_digits < AVB_MAX_DIGITS_UINT64 - 1;) { rev_digits[num_digits++] = (value % 10) + '0'; value /= 10; if (value == 0) { break; } } for (n = 0; n < num_digits; n++) { digits[n] = rev_digits[num_digits - 1 - n]; } digits[n] = '\0'; return n; } static int cmdline_append_version(AvbSlotVerifyData* slot_data, const char* key, uint64_t major_version, uint64_t minor_version) { char major_digits[AVB_MAX_DIGITS_UINT64]; char minor_digits[AVB_MAX_DIGITS_UINT64]; char combined[AVB_MAX_DIGITS_UINT64 * 2 + 1]; size_t num_major_digits, num_minor_digits; num_major_digits = uint64_to_base10(major_version, major_digits); num_minor_digits = uint64_to_base10(minor_version, minor_digits); avb_memcpy(combined, major_digits, num_major_digits); combined[num_major_digits] = '.'; avb_memcpy(combined + num_major_digits + 1, minor_digits, num_minor_digits); combined[num_major_digits + 1 + num_minor_digits] = '\0'; return cmdline_append_option(slot_data, key, combined); } static int cmdline_append_uint64_base10(AvbSlotVerifyData* slot_data, const char* key, uint64_t value) { char digits[AVB_MAX_DIGITS_UINT64]; uint64_to_base10(value, digits); return cmdline_append_option(slot_data, key, digits); } static int cmdline_append_hex(AvbSlotVerifyData* slot_data, const char* key, const uint8_t* data, size_t data_len) { char hex_digits[17] = "0123456789abcdef"; char* hex_data; int ret; size_t n; hex_data = avb_malloc(data_len * 2 + 1); if (hex_data == NULL) { return 0; } for (n = 0; n < data_len; n++) { hex_data[n * 2] = hex_digits[data[n] >> 4]; hex_data[n * 2 + 1] = hex_digits[data[n] & 0x0f]; } hex_data[n * 2] = '\0'; ret = cmdline_append_option(slot_data, key, hex_data); avb_free(hex_data); return ret; } static AvbSlotVerifyResult append_options( AvbOps* ops, AvbSlotVerifyData* slot_data, AvbVBMetaImageHeader* toplevel_vbmeta, AvbAlgorithmType algorithm_type, AvbHashtreeErrorMode hashtree_error_mode) { AvbSlotVerifyResult ret; const char* verity_mode; bool is_device_unlocked; AvbIOResult io_ret; /* Add androidboot.vbmeta.device option. */ if (!cmdline_append_option(slot_data, "androidboot.vbmeta.device", "PARTUUID=$(ANDROID_VBMETA_PARTUUID)")) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto out; } /* Add androidboot.vbmeta.avb_version option. */ if (!cmdline_append_version(slot_data, "androidboot.vbmeta.avb_version", AVB_VERSION_MAJOR, AVB_VERSION_MINOR)) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto out; } /* Set androidboot.avb.device_state to "locked" or "unlocked". */ io_ret = ops->read_is_device_unlocked(ops, &is_device_unlocked); if (io_ret == AVB_IO_RESULT_ERROR_OOM) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto out; } else if (io_ret != AVB_IO_RESULT_OK) { avb_error("Error getting device state.\n"); ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO; goto out; } if (!cmdline_append_option(slot_data, "androidboot.vbmeta.device_state", is_device_unlocked ? "unlocked" : "locked")) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto out; } /* Set androidboot.vbmeta.{hash_alg, size, digest} - use same hash * function as is used to sign vbmeta. */ switch (algorithm_type) { /* Explicit fallthrough. */ case AVB_ALGORITHM_TYPE_NONE: case AVB_ALGORITHM_TYPE_SHA256_RSA2048: case AVB_ALGORITHM_TYPE_SHA256_RSA4096: case AVB_ALGORITHM_TYPE_SHA256_RSA8192: { AvbSHA256Ctx ctx; size_t n, total_size = 0; avb_sha256_init(&ctx); for (n = 0; n < slot_data->num_vbmeta_images; n++) { avb_sha256_update(&ctx, slot_data->vbmeta_images[n].vbmeta_data, slot_data->vbmeta_images[n].vbmeta_size); total_size += slot_data->vbmeta_images[n].vbmeta_size; } if (!cmdline_append_option( slot_data, "androidboot.vbmeta.hash_alg", "sha256") || !cmdline_append_uint64_base10( slot_data, "androidboot.vbmeta.size", total_size) || !cmdline_append_hex(slot_data, "androidboot.vbmeta.digest", avb_sha256_final(&ctx), AVB_SHA256_DIGEST_SIZE)) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto out; } } break; /* Explicit fallthrough. */ case AVB_ALGORITHM_TYPE_SHA512_RSA2048: case AVB_ALGORITHM_TYPE_SHA512_RSA4096: case AVB_ALGORITHM_TYPE_SHA512_RSA8192: { AvbSHA512Ctx ctx; size_t n, total_size = 0; avb_sha512_init(&ctx); for (n = 0; n < slot_data->num_vbmeta_images; n++) { avb_sha512_update(&ctx, slot_data->vbmeta_images[n].vbmeta_data, slot_data->vbmeta_images[n].vbmeta_size); total_size += slot_data->vbmeta_images[n].vbmeta_size; } if (!cmdline_append_option( slot_data, "androidboot.vbmeta.hash_alg", "sha512") || !cmdline_append_uint64_base10( slot_data, "androidboot.vbmeta.size", total_size) || !cmdline_append_hex(slot_data, "androidboot.vbmeta.digest", avb_sha512_final(&ctx), AVB_SHA512_DIGEST_SIZE)) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto out; } } break; case _AVB_ALGORITHM_NUM_TYPES: avb_assert_not_reached(); break; } /* Set androidboot.veritymode and androidboot.vbmeta.invalidate_on_error */ if (toplevel_vbmeta->flags & AVB_VBMETA_IMAGE_FLAGS_HASHTREE_DISABLED) { verity_mode = "disabled"; } else { const char* dm_verity_mode; char* new_ret; switch (hashtree_error_mode) { case AVB_HASHTREE_ERROR_MODE_RESTART_AND_INVALIDATE: if (!cmdline_append_option( slot_data, "androidboot.vbmeta.invalidate_on_error", "yes")) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto out; } verity_mode = "enforcing"; dm_verity_mode = "restart_on_corruption"; break; case AVB_HASHTREE_ERROR_MODE_RESTART: verity_mode = "enforcing"; dm_verity_mode = "restart_on_corruption"; break; case AVB_HASHTREE_ERROR_MODE_EIO: verity_mode = "eio"; /* For now there's no option to specify the EIO mode. So * just use 'ignore_zero_blocks' since that's already set * and dm-verity-target.c supports specifying this multiple * times. */ dm_verity_mode = "ignore_zero_blocks"; break; case AVB_HASHTREE_ERROR_MODE_LOGGING: verity_mode = "logging"; dm_verity_mode = "ignore_corruption"; break; } new_ret = avb_replace( slot_data->cmdline, "$(ANDROID_VERITY_MODE)", dm_verity_mode); avb_free(slot_data->cmdline); slot_data->cmdline = new_ret; if (slot_data->cmdline == NULL) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto out; } } if (!cmdline_append_option( slot_data, "androidboot.veritymode", verity_mode)) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto out; } ret = AVB_SLOT_VERIFY_RESULT_OK; out: return ret; } static bool has_system_partition(AvbOps* ops, const char* ab_suffix) { char part_name[PART_NAME_MAX_SIZE]; char* system_part_name = "system"; char guid_buf[37]; AvbIOResult io_ret; if (!avb_str_concat(part_name, sizeof part_name, system_part_name, avb_strlen(system_part_name), ab_suffix, avb_strlen(ab_suffix))) { avb_error("System partition name and suffix does not fit.\n"); return false; } io_ret = ops->get_unique_guid_for_partition( ops, part_name, guid_buf, sizeof guid_buf); if (io_ret == AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION) { avb_debug("No system partition.\n"); return false; } else if (io_ret != AVB_IO_RESULT_OK) { avb_error("Error getting unique GUID for system partition.\n"); return false; } return true; } AvbSlotVerifyResult avb_slot_verify(AvbOps* ops, const char* const* requested_partitions, const char* ab_suffix, AvbSlotVerifyFlags flags, AvbHashtreeErrorMode hashtree_error_mode, AvbSlotVerifyData** out_data) { AvbSlotVerifyResult ret; AvbSlotVerifyData* slot_data = NULL; AvbAlgorithmType algorithm_type = AVB_ALGORITHM_TYPE_NONE; bool using_boot_for_vbmeta = false; AvbVBMetaImageHeader toplevel_vbmeta; bool allow_verification_error = (flags & AVB_SLOT_VERIFY_FLAGS_ALLOW_VERIFICATION_ERROR); /* Fail early if we're missing the AvbOps needed for slot verification. */ avb_assert(ops->read_is_device_unlocked != NULL); avb_assert(ops->read_from_partition != NULL); avb_assert(ops->get_size_of_partition != NULL); avb_assert(ops->validate_vbmeta_public_key != NULL); avb_assert(ops->read_rollback_index != NULL); avb_assert(ops->get_unique_guid_for_partition != NULL); /* avb_assert(ops->get_size_of_partition != NULL); */ if (out_data != NULL) { *out_data = NULL; } /* Allowing dm-verity errors defeats the purpose of verified boot so * only allow this if set up to allow verification errors * (e.g. typically only UNLOCKED mode). */ if (hashtree_error_mode == AVB_HASHTREE_ERROR_MODE_LOGGING && !allow_verification_error) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_ARGUMENT; goto fail; } slot_data = avb_calloc(sizeof(AvbSlotVerifyData)); if (slot_data == NULL) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto fail; } slot_data->vbmeta_images = avb_calloc(sizeof(AvbVBMetaData) * MAX_NUMBER_OF_VBMETA_IMAGES); if (slot_data->vbmeta_images == NULL) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto fail; } slot_data->loaded_partitions = avb_calloc(sizeof(AvbPartitionData) * MAX_NUMBER_OF_LOADED_PARTITIONS); if (slot_data->loaded_partitions == NULL) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto fail; } ret = load_and_verify_vbmeta(ops, requested_partitions, ab_suffix, allow_verification_error, 0 /* toplevel_vbmeta_flags */, 0 /* rollback_index_location */, "vbmeta", avb_strlen("vbmeta"), NULL /* expected_public_key */, 0 /* expected_public_key_length */, slot_data, &algorithm_type); if ((!allow_verification_error && ret != AVB_SLOT_VERIFY_RESULT_OK) || !result_should_continue(ret)) { goto fail; } /* If things check out, mangle the kernel command-line as needed. */ if (result_should_continue(ret)) { if (avb_strcmp(slot_data->vbmeta_images[0].partition_name, "vbmeta") != 0) { avb_assert( avb_strcmp(slot_data->vbmeta_images[0].partition_name, "boot") == 0); using_boot_for_vbmeta = true; } /* Byteswap top-level vbmeta header since we'll need it below. */ avb_vbmeta_image_header_to_host_byte_order( (const AvbVBMetaImageHeader*)slot_data->vbmeta_images[0].vbmeta_data, &toplevel_vbmeta); /* Fill in |ab_suffix| field. */ slot_data->ab_suffix = avb_strdup(ab_suffix); if (slot_data->ab_suffix == NULL) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto fail; } /* If verification is disabled, we are done ... we specifically * don't want to add any androidboot.* options since verification * is disabled. */ if (toplevel_vbmeta.flags & AVB_VBMETA_IMAGE_FLAGS_VERIFICATION_DISABLED) { /* Since verification is disabled we didn't process any * descriptors and thus there's no cmdline... so set root= such * that the system partition is mounted. */ avb_assert(slot_data->cmdline == NULL); // Devices with dynamic partitions won't have system partition. // Instead, it has a large super partition to accommodate *.img files. // See b/119551429 for details. if (has_system_partition(ops, ab_suffix)) { slot_data->cmdline = avb_strdup("root=PARTUUID=$(ANDROID_SYSTEM_PARTUUID)"); } else { // The |cmdline| field should be a NUL-terminated string. slot_data->cmdline = avb_strdup(""); } if (slot_data->cmdline == NULL) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto fail; } } else { /* Add options - any failure in append_options() is either an * I/O or OOM error. */ AvbSlotVerifyResult sub_ret = append_options(ops, slot_data, &toplevel_vbmeta, algorithm_type, hashtree_error_mode); if (sub_ret != AVB_SLOT_VERIFY_RESULT_OK) { ret = sub_ret; goto fail; } } /* Substitute $(ANDROID_SYSTEM_PARTUUID) and friends. */ if (slot_data->cmdline != NULL && avb_strlen(slot_data->cmdline) != 0) { char* new_cmdline; new_cmdline = sub_cmdline( ops, slot_data->cmdline, ab_suffix, using_boot_for_vbmeta); if (new_cmdline == NULL) { ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; goto fail; } avb_free(slot_data->cmdline); slot_data->cmdline = new_cmdline; } if (out_data != NULL) { *out_data = slot_data; } else { avb_slot_verify_data_free(slot_data); } } if (!allow_verification_error) { avb_assert(ret == AVB_SLOT_VERIFY_RESULT_OK); } return ret; fail: if (slot_data != NULL) { avb_slot_verify_data_free(slot_data); } return ret; } void avb_slot_verify_data_free(AvbSlotVerifyData* data) { if (data->ab_suffix != NULL) { avb_free(data->ab_suffix); } if (data->cmdline != NULL) { avb_free(data->cmdline); } if (data->vbmeta_images != NULL) { size_t n; for (n = 0; n < data->num_vbmeta_images; n++) { AvbVBMetaData* vbmeta_image = &data->vbmeta_images[n]; if (vbmeta_image->partition_name != NULL) { avb_free(vbmeta_image->partition_name); } if (vbmeta_image->vbmeta_data != NULL) { avb_free(vbmeta_image->vbmeta_data); } } avb_free(data->vbmeta_images); } if (data->loaded_partitions != NULL) { size_t n; for (n = 0; n < data->num_loaded_partitions; n++) { AvbPartitionData* loaded_partition = &data->loaded_partitions[n]; if (loaded_partition->partition_name != NULL) { avb_free(loaded_partition->partition_name); } if (loaded_partition->data != NULL) { avb_free(loaded_partition->data); } } avb_free(data->loaded_partitions); } avb_free(data); } const char* avb_slot_verify_result_to_string(AvbSlotVerifyResult result) { const char* ret = NULL; switch (result) { case AVB_SLOT_VERIFY_RESULT_OK: ret = "OK"; break; case AVB_SLOT_VERIFY_RESULT_ERROR_OOM: ret = "ERROR_OOM"; break; case AVB_SLOT_VERIFY_RESULT_ERROR_IO: ret = "ERROR_IO"; break; case AVB_SLOT_VERIFY_RESULT_ERROR_VERIFICATION: ret = "ERROR_VERIFICATION"; break; case AVB_SLOT_VERIFY_RESULT_ERROR_ROLLBACK_INDEX: ret = "ERROR_ROLLBACK_INDEX"; break; case AVB_SLOT_VERIFY_RESULT_ERROR_PUBLIC_KEY_REJECTED: ret = "ERROR_PUBLIC_KEY_REJECTED"; break; case AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA: ret = "ERROR_INVALID_METADATA"; break; case AVB_SLOT_VERIFY_RESULT_ERROR_UNSUPPORTED_VERSION: ret = "ERROR_UNSUPPORTED_VERSION"; break; case AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_ARGUMENT: ret = "ERROR_INVALID_ARGUMENT"; break; /* Do not add a 'default:' case here because of -Wswitch. */ } if (ret == NULL) { avb_error("Unknown AvbSlotVerifyResult value.\n"); ret = "(unknown)"; } return ret; }