Implement AVB ops on top of existing mmc subsystem API. Currently there is a full implementation of such operations, defined by [1] AVB2.0 specification:
.read_from_partition() - reads N bytes from a partition identified by a name. .write_to_partition() - Writes N bytes to a partition identified by a name. .validate_vbmeta_public_key() - checks if the given public ‘vbmeta’ partition is trusted. .get_unique_guid_for_partition() - Gets the GUID for a partition identified by a string name.
As [1] specification recommends to use tamper-evident storage for storing rollback indexes and device state (LOCKED/UNLOCKED), currently are only stubs instead of full implementation for these ops: .read_rollback_index() - Gets the rollback index for a given index location .write_rollback_index() - Sets the rollback index to a given location .read_is_device_unlocked() - Gets where the device is unlocked
[1] https://android.googlesource.com/platform/external/avb/+/master/README.md
Signed-off-by: Igor Opaniuk igor.opaniuk@linaro.org --- common/Makefile | 2 + common/avb_verify.c | 610 +++++++++++++++++++++++++++++++++++++++++++++++++++ include/avb_verify.h | 79 +++++++ 3 files changed, 691 insertions(+) create mode 100644 common/avb_verify.c create mode 100644 include/avb_verify.h
diff --git a/common/Makefile b/common/Makefile index 7011dad..8ba0b79 100644 --- a/common/Makefile +++ b/common/Makefile @@ -136,3 +136,5 @@ obj-$(CONFIG_$(SPL_)LOG) += log.o obj-$(CONFIG_$(SPL_)LOG_CONSOLE) += log_console.o obj-y += s_record.o obj-y += xyzModem.o + +obj-$(CONFIG_LIBAVB) += avb_verify.o diff --git a/common/avb_verify.c b/common/avb_verify.c new file mode 100644 index 0000000..a4de168 --- /dev/null +++ b/common/avb_verify.c @@ -0,0 +1,610 @@ +/* + * (C) Copyright 2018, Linaro Limited + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <avb_verify.h> +#include <fastboot.h> +#include <image.h> +#include <malloc.h> +#include <part.h> + +const unsigned char avb_root_pub[1032] = { + 0x0, 0x0, 0x10, 0x0, 0x55, 0xd9, 0x4, 0xad, 0xd8, 0x4, + 0xaf, 0xe3, 0xd3, 0x84, 0x6c, 0x7e, 0xd, 0x89, 0x3d, 0xc2, + 0x8c, 0xd3, 0x12, 0x55, 0xe9, 0x62, 0xc9, 0xf1, 0xf, 0x5e, + 0xcc, 0x16, 0x72, 0xab, 0x44, 0x7c, 0x2c, 0x65, 0x4a, 0x94, + 0xb5, 0x16, 0x2b, 0x0, 0xbb, 0x6, 0xef, 0x13, 0x7, 0x53, + 0x4c, 0xf9, 0x64, 0xb9, 0x28, 0x7a, 0x1b, 0x84, 0x98, 0x88, + 0xd8, 0x67, 0xa4, 0x23, 0xf9, 0xa7, 0x4b, 0xdc, 0x4a, 0xf, + 0xf7, 0x3a, 0x18, 0xae, 0x54, 0xa8, 0x15, 0xfe, 0xb0, 0xad, + 0xac, 0x35, 0xda, 0x3b, 0xad, 0x27, 0xbc, 0xaf, 0xe8, 0xd3, + 0x2f, 0x37, 0x34, 0xd6, 0x51, 0x2b, 0x6c, 0x5a, 0x27, 0xd7, + 0x96, 0x6, 0xaf, 0x6b, 0xb8, 0x80, 0xca, 0xfa, 0x30, 0xb4, + 0xb1, 0x85, 0xb3, 0x4d, 0xaa, 0xaa, 0xc3, 0x16, 0x34, 0x1a, + 0xb8, 0xe7, 0xc7, 0xfa, 0xf9, 0x9, 0x77, 0xab, 0x97, 0x93, + 0xeb, 0x44, 0xae, 0xcf, 0x20, 0xbc, 0xf0, 0x80, 0x11, 0xdb, + 0x23, 0xc, 0x47, 0x71, 0xb9, 0x6d, 0xd6, 0x7b, 0x60, 0x47, + 0x87, 0x16, 0x56, 0x93, 0xb7, 0xc2, 0x2a, 0x9a, 0xb0, 0x4c, + 0x1, 0xc, 0x30, 0xd8, 0x93, 0x87, 0xf0, 0xed, 0x6e, 0x8b, + 0xbe, 0x30, 0x5b, 0xf6, 0xa6, 0xaf, 0xdd, 0x80, 0x7c, 0x45, + 0x5e, 0x8f, 0x91, 0x93, 0x5e, 0x44, 0xfe, 0xb8, 0x82, 0x7, + 0xee, 0x79, 0xca, 0xbf, 0x31, 0x73, 0x62, 0x58, 0xe3, 0xcd, + 0xc4, 0xbc, 0xc2, 0x11, 0x1d, 0xa1, 0x4a, 0xbf, 0xfe, 0x27, + 0x7d, 0xa1, 0xf6, 0x35, 0xa3, 0x5e, 0xca, 0xdc, 0x57, 0x2f, + 0x3e, 0xf0, 0xc9, 0x5d, 0x86, 0x6a, 0xf8, 0xaf, 0x66, 0xa7, + 0xed, 0xcd, 0xb8, 0xed, 0xa1, 0x5f, 0xba, 0x9b, 0x85, 0x1a, + 0xd5, 0x9, 0xae, 0x94, 0x4e, 0x3b, 0xcf, 0xcb, 0x5c, 0xc9, + 0x79, 0x80, 0xf7, 0xcc, 0xa6, 0x4a, 0xa8, 0x6a, 0xd8, 0xd3, + 0x31, 0x11, 0xf9, 0xf6, 0x2, 0x63, 0x2a, 0x1a, 0x2d, 0xd1, + 0x1a, 0x66, 0x1b, 0x16, 0x41, 0xbd, 0xbd, 0xf7, 0x4d, 0xc0, + 0x4a, 0xe5, 0x27, 0x49, 0x5f, 0x7f, 0x58, 0xe3, 0x27, 0x2d, + 0xe5, 0xc9, 0x66, 0xe, 0x52, 0x38, 0x16, 0x38, 0xfb, 0x16, + 0xeb, 0x53, 0x3f, 0xe6, 0xfd, 0xe9, 0xa2, 0x5e, 0x25, 0x59, + 0xd8, 0x79, 0x45, 0xff, 0x3, 0x4c, 0x26, 0xa2, 0x0, 0x5a, + 0x8e, 0xc2, 0x51, 0xa1, 0x15, 0xf9, 0x7b, 0xf4, 0x5c, 0x81, + 0x9b, 0x18, 0x47, 0x35, 0xd8, 0x2d, 0x5, 0xe9, 0xad, 0xf, + 0x35, 0x74, 0x15, 0xa3, 0x8e, 0x8b, 0xcc, 0x27, 0xda, 0x7c, + 0x5d, 0xe4, 0xfa, 0x4, 0xd3, 0x5, 0xb, 0xba, 0x3a, 0xb2, + 0x49, 0x45, 0x2f, 0x47, 0xc7, 0xd, 0x41, 0x3f, 0x97, 0x80, + 0x4d, 0x3f, 0xc1, 0xb5, 0xbb, 0x70, 0x5f, 0xa7, 0x37, 0xaf, + 0x48, 0x22, 0x12, 0x45, 0x2e, 0xf5, 0xf, 0x87, 0x92, 0xe2, + 0x84, 0x1, 0xf9, 0x12, 0xf, 0x14, 0x15, 0x24, 0xce, 0x89, + 0x99, 0xee, 0xb9, 0xc4, 0x17, 0x70, 0x70, 0x15, 0xea, 0xbe, + 0xc6, 0x6c, 0x1f, 0x62, 0xb3, 0xf4, 0x2d, 0x16, 0x87, 0xfb, + 0x56, 0x1e, 0x45, 0xab, 0xae, 0x32, 0xe4, 0x5e, 0x91, 0xed, + 0x53, 0x66, 0x5e, 0xbd, 0xed, 0xad, 0xe6, 0x12, 0x39, 0xd, + 0x83, 0xc9, 0xe8, 0x6b, 0x6c, 0x2d, 0xa5, 0xee, 0xc4, 0x5a, + 0x66, 0xae, 0x8c, 0x97, 0xd7, 0xd, 0x6c, 0x49, 0xc7, 0xf5, + 0xc4, 0x92, 0x31, 0x8b, 0x9, 0xee, 0x33, 0xda, 0xa9, 0x37, + 0xb6, 0x49, 0x18, 0xf8, 0xe, 0x60, 0x45, 0xc8, 0x33, 0x91, + 0xef, 0x20, 0x57, 0x10, 0xbe, 0x78, 0x2d, 0x83, 0x26, 0xd6, + 0xca, 0x61, 0xf9, 0x2f, 0xe0, 0xbf, 0x5, 0x30, 0x52, 0x5a, + 0x12, 0x1c, 0x0, 0xa7, 0x5d, 0xcc, 0x7c, 0x2e, 0xc5, 0x95, + 0x8b, 0xa3, 0x3b, 0xf0, 0x43, 0x2e, 0x5e, 0xdd, 0x0, 0xdb, + 0xd, 0xb3, 0x37, 0x99, 0xa9, 0xcd, 0x9c, 0xb7, 0x43, 0xf7, + 0x35, 0x44, 0x21, 0xc2, 0x82, 0x71, 0xab, 0x8d, 0xaa, 0xb4, + 0x41, 0x11, 0xec, 0x1e, 0x8d, 0xfc, 0x14, 0x82, 0x92, 0x4e, + 0x83, 0x6a, 0xa, 0x6b, 0x35, 0x5e, 0x5d, 0xe9, 0x5c, 0xcc, + 0x8c, 0xde, 0x39, 0xd1, 0x4a, 0x5b, 0x5f, 0x63, 0xa9, 0x64, + 0xe0, 0xa, 0xcb, 0xb, 0xb8, 0x5a, 0x7c, 0xc3, 0xb, 0xe6, + 0xbe, 0xfe, 0x8b, 0xf, 0x7d, 0x34, 0x8e, 0x2, 0x66, 0x74, + 0x1, 0x6c, 0xca, 0x76, 0xac, 0x7c, 0x67, 0x8, 0x2f, 0x3f, + 0x1a, 0xa6, 0x2c, 0x60, 0xb3, 0xff, 0xda, 0x8d, 0xb8, 0x12, + 0xc, 0x0, 0x7f, 0xcc, 0x50, 0xa1, 0x5c, 0x64, 0xa1, 0xe2, + 0x5f, 0x32, 0x65, 0xc9, 0x9c, 0xbe, 0xd6, 0xa, 0x13, 0x87, + 0x3c, 0x2a, 0x45, 0x47, 0xc, 0xca, 0x42, 0x82, 0xfa, 0x89, + 0x65, 0xe7, 0x89, 0xb4, 0x8f, 0xf7, 0x1e, 0xe6, 0x23, 0xa5, + 0xd0, 0x59, 0x37, 0x79, 0x92, 0xd7, 0xce, 0x3d, 0xfd, 0xe3, + 0xa1, 0xb, 0xcf, 0x6c, 0x85, 0xa0, 0x65, 0xf3, 0x5c, 0xc6, + 0x4a, 0x63, 0x5f, 0x6e, 0x3a, 0x3a, 0x2a, 0x8b, 0x6a, 0xb6, + 0x2f, 0xbb, 0xf8, 0xb2, 0x4b, 0x62, 0xbc, 0x1a, 0x91, 0x25, + 0x66, 0xe3, 0x69, 0xca, 0x60, 0x49, 0xb, 0xf6, 0x8a, 0xbe, + 0x3e, 0x76, 0x53, 0xc2, 0x7a, 0xa8, 0x4, 0x17, 0x75, 0xf1, + 0xf3, 0x3, 0x62, 0x1b, 0x85, 0xb2, 0xb0, 0xef, 0x80, 0x15, + 0xb6, 0xd4, 0x4e, 0xdf, 0x71, 0xac, 0xdb, 0x2a, 0x4, 0xd4, + 0xb4, 0x21, 0xba, 0x65, 0x56, 0x57, 0xe8, 0xfa, 0x84, 0xa2, + 0x7d, 0x13, 0xe, 0xaf, 0xd7, 0x9a, 0x58, 0x2a, 0xa3, 0x81, + 0x84, 0x8d, 0x9, 0xa0, 0x6a, 0xc1, 0xbb, 0xd9, 0xf5, 0x86, + 0xac, 0xbd, 0x75, 0x61, 0x9, 0xe6, 0x8c, 0x3d, 0x77, 0xb2, + 0xed, 0x30, 0x20, 0xe4, 0x0, 0x1d, 0x97, 0xe8, 0xbf, 0xc7, + 0x0, 0x1b, 0x21, 0xb1, 0x16, 0xe7, 0x41, 0x67, 0x2e, 0xec, + 0x38, 0xbc, 0xe5, 0x1b, 0xb4, 0x6, 0x23, 0x31, 0x71, 0x1c, + 0x49, 0xcd, 0x76, 0x4a, 0x76, 0x36, 0x8d, 0xa3, 0x89, 0x8b, + 0x4a, 0x7a, 0xf4, 0x87, 0xc8, 0x15, 0xf, 0x37, 0x39, 0xf6, + 0x6d, 0x80, 0x19, 0xef, 0x5c, 0xa8, 0x66, 0xce, 0x1b, 0x16, + 0x79, 0x21, 0xdf, 0xd7, 0x31, 0x30, 0xc4, 0x21, 0xdd, 0x34, + 0x5b, 0xd2, 0x1a, 0x2b, 0x3e, 0x5d, 0xf7, 0xea, 0xca, 0x5, + 0x8e, 0xb7, 0xcb, 0x49, 0x2e, 0xa0, 0xe3, 0xf4, 0xa7, 0x48, + 0x19, 0x10, 0x9c, 0x4, 0xa7, 0xf4, 0x28, 0x74, 0xc8, 0x6f, + 0x63, 0x20, 0x2b, 0x46, 0x24, 0x26, 0x19, 0x1d, 0xd1, 0x2c, + 0x31, 0x6d, 0x5a, 0x29, 0xa2, 0x6, 0xa6, 0xb2, 0x41, 0xcc, + 0xa, 0x27, 0x96, 0x9, 0x96, 0xac, 0x47, 0x65, 0x78, 0x68, + 0x51, 0x98, 0xd6, 0xd8, 0xa6, 0x2d, 0xa0, 0xcf, 0xec, 0xe2, + 0x74, 0xf2, 0x82, 0xe3, 0x97, 0xd9, 0x7e, 0xd4, 0xf8, 0xb, + 0x70, 0x43, 0x3d, 0xb1, 0x7b, 0x97, 0x80, 0xd6, 0xcb, 0xd7, + 0x19, 0xbc, 0x63, 0xb, 0xfd, 0x4d, 0x88, 0xfe, 0x67, 0xac, + 0xb8, 0xcc, 0x50, 0xb7, 0x68, 0xb3, 0x5b, 0xd6, 0x1e, 0x25, + 0xfc, 0x5f, 0x3c, 0x8d, 0xb1, 0x33, 0x7c, 0xb3, 0x49, 0x1, + 0x3f, 0x71, 0x55, 0xe, 0x51, 0xba, 0x61, 0x26, 0xfa, 0xea, + 0xe5, 0xb5, 0xe8, 0xaa, 0xcf, 0xcd, 0x96, 0x9f, 0xd6, 0xc1, + 0x5f, 0x53, 0x91, 0xad, 0x5, 0xde, 0x20, 0xe7, 0x51, 0xda, + 0x5b, 0x95, 0x67, 0xed, 0xf4, 0xee, 0x42, 0x65, 0x70, 0x13, + 0xb, 0x70, 0x14, 0x1c, 0xc9, 0xe0, 0x19, 0xca, 0x5f, 0xf5, + 0x1d, 0x70, 0x4b, 0x6c, 0x6, 0x74, 0xec, 0xb5, 0x2e, 0x77, + 0xe1, 0x74, 0xa1, 0xa3, 0x99, 0xa0, 0x85, 0x9e, 0xf1, 0xac, + 0xd8, 0x7e, +}; + +/** + * ============================================================================ + * IO(mmc) auxiliary functions + * ============================================================================ + */ +static unsigned long mmc_read_and_flush(struct mmc_part *part, + lbaint_t start, + lbaint_t sectors, + void *buffer) +{ + unsigned long blks; + void *tmp_buf; + size_t buf_size; + bool unaligned = is_buf_unaligned(buffer); + + if (start < part->info.start) { + printf("%s: partition start out of bounds\n", __func__); + return 0; + } + if ((start + sectors) > (part->info.start + part->info.size)) { + sectors = part->info.start + part->info.size - start; + printf("%s: read sector aligned to partition bounds (%ld)\n", + __func__, sectors); + } + + /* + * Reading fails on unaligned buffers, so we have to + * use aligned temporary buffer and then copy to destination + */ + + if (unaligned) { + printf("Handling unaligned read buffer..\n"); + tmp_buf = get_sector_buf(); + buf_size = get_sector_buf_size(); + if (sectors > buf_size / part->info.blksz) + sectors = buf_size / part->info.blksz; + } else { + tmp_buf = buffer; + } + + blks = part->mmc->block_dev.block_read(part->mmc_blk, + start, sectors, tmp_buf); + /* flush cache after read */ + flush_cache((ulong)tmp_buf, sectors * part->info.blksz); + + if (unaligned) + memcpy(buffer, tmp_buf, sectors * part->info.blksz); + + return blks; +} + +static unsigned long mmc_write(struct mmc_part *part, lbaint_t start, + lbaint_t sectors, void *buffer) +{ + void *tmp_buf; + size_t buf_size; + bool unaligned = is_buf_unaligned(buffer); + + if (start < part->info.start) { + printf("%s: partition start out of bounds\n", __func__); + return 0; + } + if ((start + sectors) > (part->info.start + part->info.size)) { + sectors = part->info.start + part->info.size - start; + printf("%s: sector aligned to partition bounds (%ld)\n", + __func__, sectors); + } + if (unaligned) { + tmp_buf = get_sector_buf(); + buf_size = get_sector_buf_size(); + printf("Handling unaligned wrire buffer..\n"); + if (sectors > buf_size / part->info.blksz) + sectors = buf_size / part->info.blksz; + + memcpy(tmp_buf, buffer, sectors * part->info.blksz); + } else { + tmp_buf = buffer; + } + + return part->mmc->block_dev.block_write(part->mmc_blk, + start, sectors, tmp_buf); +} + +static struct mmc_part *get_partition(AvbOps *ops, const char *partition) +{ + int ret; + u8 dev_num; + int part_num = 0; + struct mmc_part *part; + struct blk_desc *mmc_blk; + + part = malloc(sizeof(struct mmc_part)); + if (!part) + return NULL; + + dev_num = get_boot_device(ops); + part->mmc = find_mmc_device(dev_num); + if (!part->mmc) { + printf("No MMC device at slot %x\n", dev_num); + return NULL; + } + + if (mmc_init(part->mmc)) { + printf("MMC initialization failed\n"); + return NULL; + } + + ret = mmc_switch_part(part->mmc, part_num); + if (ret) + return NULL; + + mmc_blk = mmc_get_blk_desc(part->mmc); + if (!mmc_blk) { + printf("Error - failed to obtain block descriptor\n"); + return NULL; + } + + ret = part_get_info_by_name(mmc_blk, partition, &part->info); + if (!ret) { + printf("Can't find partition '%s'\n", partition); + return NULL; + } + + part->dev_num = dev_num; + part->mmc_blk = mmc_blk; + + return part; +} + +static AvbIOResult mmc_byte_io(AvbOps *ops, + const char *partition, + s64 offset, + size_t num_bytes, + void *buffer, + size_t *out_num_read, + enum mmc_io_type io_type) +{ + ulong ret; + struct mmc_part *part; + u64 start_offset, start_sector, sectors, residue; + u8 *tmp_buf; + size_t io_cnt = 0; + + if (!partition || !buffer || io_type > IO_WRITE) + return AVB_IO_RESULT_ERROR_IO; + + part = get_partition(ops, partition); + if (!part) + return AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION; + + start_offset = calc_offset(part, offset); + while (num_bytes) { + start_sector = start_offset / part->info.blksz; + sectors = num_bytes / part->info.blksz; + /* handle non block-aligned reads */ + if (start_offset % part->info.blksz || + num_bytes < part->info.blksz) { + tmp_buf = get_sector_buf(); + if (start_offset % part->info.blksz) { + residue = part->info.blksz - + (start_offset % part->info.blksz); + if (residue > num_bytes) + residue = num_bytes; + } else { + residue = num_bytes; + } + + if (io_type == IO_READ) { + ret = mmc_read_and_flush(part, + part->info.start + + start_sector, + 1, tmp_buf); + + if (ret != 1) { + printf("%s: read error (%ld, %lld)\n", + __func__, ret, start_sector); + return AVB_IO_RESULT_ERROR_IO; + } + /* + * if this is not aligned at sector start, + * we have to adjust the tmp buffer + */ + tmp_buf += (start_offset % part->info.blksz); + memcpy(buffer, (void *)tmp_buf, residue); + } else { + ret = mmc_read_and_flush(part, + part->info.start + + start_sector, + 1, tmp_buf); + + if (ret != 1) { + printf("%s: read error (%ld, %lld)\n", + __func__, ret, start_sector); + return AVB_IO_RESULT_ERROR_IO; + } + memcpy((void *)tmp_buf + + start_offset % part->info.blksz, + buffer, residue); + + ret = mmc_write(part, part->info.start + + start_sector, 1, tmp_buf); + if (ret != 1) { + printf("%s: write error (%ld, %lld)\n", + __func__, ret, start_sector); + return AVB_IO_RESULT_ERROR_IO; + } + } + + io_cnt += residue; + buffer += residue; + start_offset += residue; + num_bytes -= residue; + continue; + } + + if (sectors) { + if (io_type == IO_READ) { + ret = mmc_read_and_flush(part, + part->info.start + + start_sector, + sectors, buffer); + } else { + ret = mmc_write(part, + part->info.start + + start_sector, + sectors, buffer); + } + + if (!ret) { + printf("%s: sector read error\n", __func__); + return AVB_IO_RESULT_ERROR_IO; + } + + io_cnt += ret * part->info.blksz; + buffer += ret * part->info.blksz; + start_offset += ret * part->info.blksz; + num_bytes -= ret * part->info.blksz; + } + } + + /* Set counter for read operation */ + if (io_type == IO_READ && out_num_read) + *out_num_read = io_cnt; + + return AVB_IO_RESULT_OK; +} + +/** + * ============================================================================ + * AVB 2.0 operations + * ============================================================================ + */ + +/** + * read_from_partition() - reads @num_bytes from @offset from partition + * identified by a string name + * + * @ops: contains AVB ops handlers + * @partition_name: partition name, NUL-terminated UTF-8 string + * @offset: offset from the beginning of partition + * @num_bytes: amount of bytes to read + * @buffer: destination buffer to store data + * @out_num_read: + * + * @return: + * AVB_IO_RESULT_OK, if partition was found and read operation succeed + * AVB_IO_RESULT_ERROR_IO, if i/o error occurred from the underlying i/o + * subsystem + * AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION, if there is no partition with + * the given name + */ +static AvbIOResult read_from_partition(AvbOps *ops, + const char *partition_name, + s64 offset_from_partition, + size_t num_bytes, + void *buffer, + size_t *out_num_read) +{ + return mmc_byte_io(ops, partition_name, offset_from_partition, + num_bytes, buffer, out_num_read, IO_READ); +} + +/** + * write_to_partition() - writes N bytes to a partition identified by a string + * name + * + * @ops: AvbOps, contains AVB ops handlers + * @partition_name: partition name + * @offset_from_partition: offset from the beginning of partition + * @num_bytes: amount of bytes to write + * @buf: data to write + * @out_num_read: + * + * @return: + * AVB_IO_RESULT_OK, if partition was found and read operation succeed + * AVB_IO_RESULT_ERROR_IO, if input/output error occurred + * AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION, if partition, specified in + * @partition_name was not found + */ +static AvbIOResult write_to_partition(AvbOps *ops, + const char *partition_name, + s64 offset_from_partition, + size_t num_bytes, + const void *buffer) +{ + return mmc_byte_io(ops, partition_name, offset_from_partition, + num_bytes, (void *)buffer, NULL, IO_WRITE); +} + +/** + * validate_vmbeta_public_key() - checks if the given public key used to sign + * the vbmeta partition is trusted + * + * @ops: AvbOps, contains AVB ops handlers + * @public_key_data: public key for verifying vbmeta partition signature + * @public_key_length: length of public key + * @public_key_metadata: + * @public_key_metadata_length: + * @out_key_is_trusted: + * + * @return: + * AVB_IO_RESULT_OK, if partition was found and read operation succeed + */ +static AvbIOResult validate_vbmeta_public_key(AvbOps *ops, + const u8 *public_key_data, + size_t public_key_length, + const u8 + *public_key_metadata, + size_t + public_key_metadata_length, + bool *out_key_is_trusted) +{ + if (!public_key_length || !public_key_data || !out_key_is_trusted) + return AVB_IO_RESULT_ERROR_IO; + + *out_key_is_trusted = false; + if (public_key_length != sizeof(avb_root_pub)) + return AVB_IO_RESULT_ERROR_IO; + + if (memcmp(avb_root_pub, public_key_data, public_key_length) == 0) + *out_key_is_trusted = true; + + return AVB_IO_RESULT_OK; +} + +/** + * read_rollback_index() - gets the rollback index corresponding to the + * location of given by @out_rollback_index. + * + * @ops: contains AvbOps handlers + * @rollback_index_slot: + * @out_rollback_index: used to write a retrieved rollback index. + * + * @return + * AVB_IO_RESULT_OK, if the roolback index was retrieved + */ +static AvbIOResult read_rollback_index(AvbOps *ops, + size_t rollback_index_slot, + u64 *out_rollback_index) +{ + /* For now we always return 0 as the stored rollback index. */ + printf("TODO: implement %s.\n", __func__); + + if (out_rollback_index) + *out_rollback_index = 0; + + return AVB_IO_RESULT_OK; +} + +/** + * write_rollback_index() - sets the rollback index corresponding to the + * location of given by @out_rollback_index. + * + * @ops: contains AvbOps handlers + * @rollback_index_slot: + * @rollback_index: rollback index to write. + * + * @return + * AVB_IO_RESULT_OK, if the roolback index was retrieved + */ +static AvbIOResult write_rollback_index(AvbOps *ops, + size_t rollback_index_slot, + u64 rollback_index) +{ + /* For now this is a no-op. */ + printf("TODO: implement %s.\n", __func__); + + return AVB_IO_RESULT_OK; +} + +/** + * read_is_device_unlocked() - gets whether the device is unlocked + * + * @ops: contains AVB ops handlers + * @out_is_unlocked: device unlock state is stored here, true if unlocked, + * false otherwise + * + * @return: + * AVB_IO_RESULT_OK: state is retrieved successfully + * AVB_IO_RESULT_ERROR_IO: an error occurred + */ +static AvbIOResult read_is_device_unlocked(AvbOps *ops, bool *out_is_unlocked) +{ + /* For now we always return that the device is unlocked. */ + + printf("TODO: implement %s.\n", __func__); + + *out_is_unlocked = true; + + return AVB_IO_RESULT_OK; +} + +/** + * get_unique_guid_for_partition() - gets the GUID for a partition identified + * by a string name + * + * @ops: contains AVB ops handlers + * @partition: partition name (NUL-terminated UTF-8 string) + * @guid_buf: buf, used to copy in GUID string. Example of value: + * 527c1c6d-6361-4593-8842-3c78fcd39219 + * @guid_buf_size: @guid_buf buffer size + * + * @return: + * AVB_IO_RESULT_OK, on success (GUID found) + * AVB_IO_RESULT_ERROR_IO, if incorrect buffer size (@guid_buf_size) was + * provided + * AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION, if partition was not found + */ +static AvbIOResult get_unique_guid_for_partition(AvbOps *ops, + const char *partition, + char *guid_buf, + size_t guid_buf_size) +{ + struct mmc_part *part; + size_t uuid_size; + + part = get_partition(ops, partition); + if (!part) + return AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION; + + uuid_size = sizeof(part->info.uuid); + if (uuid_size > guid_buf_size) + return AVB_IO_RESULT_ERROR_IO; + + memcpy(guid_buf, part->info.uuid, uuid_size); + guid_buf[uuid_size - 1] = 0; + + return AVB_IO_RESULT_OK; +} + +/** + * ============================================================================ + * AVB2.0 AvbOps alloc/initialisation/free + * ============================================================================ + */ +AvbOps *avb_ops_alloc(int boot_device) +{ + struct AvbOpsData *ops_data; + + ops_data = avb_calloc(sizeof(struct AvbOpsData)); + if (!ops_data) + return NULL; + + ops_data->ops.user_data = ops_data; + + ops_data->ops.read_from_partition = read_from_partition; + ops_data->ops.write_to_partition = write_to_partition; + ops_data->ops.validate_vbmeta_public_key = validate_vbmeta_public_key; + ops_data->ops.read_rollback_index = read_rollback_index; + ops_data->ops.write_rollback_index = write_rollback_index; + ops_data->ops.read_is_device_unlocked = read_is_device_unlocked; + ops_data->ops.get_unique_guid_for_partition = + get_unique_guid_for_partition; + + ops_data->mmc_dev = boot_device; + + return &ops_data->ops; +} + +void avb_ops_free(AvbOps *ops) +{ + struct AvbOpsData *ops_data; + + if (ops) + return; + + ops_data = ops->user_data; + + if (ops_data) + avb_free(ops_data); +} diff --git a/include/avb_verify.h b/include/avb_verify.h new file mode 100644 index 0000000..428c69a --- /dev/null +++ b/include/avb_verify.h @@ -0,0 +1,79 @@ + +/* + * (C) Copyright 2018, Linaro Limited + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#ifndef _AVB_VERIFY_H +#define _AVB_VERIFY_H + +#include <../lib/libavb/libavb.h> +#include <mmc.h> + +#define ALLOWED_BUF_ALIGN 8 + +struct AvbOpsData { + struct AvbOps ops; + int mmc_dev; +}; + +struct mmc_part { + int dev_num; + struct mmc *mmc; + struct blk_desc *mmc_blk; + disk_partition_t info; +}; + +enum mmc_io_type { + IO_READ, + IO_WRITE +}; + +AvbOps *avb_ops_alloc(int boot_device); +void avb_ops_free(AvbOps *ops); + +/** + * ============================================================================ + * I/O helper inline functions + * ============================================================================ + */ +static inline uint64_t calc_offset(struct mmc_part *part, int64_t offset) +{ + u64 part_size = part->info.size * part->info.blksz; + + if (offset < 0) + return part_size + offset; + + return offset; +} + +static inline size_t get_sector_buf_size(void) +{ + return (size_t)CONFIG_FASTBOOT_BUF_SIZE; +} + +static inline void *get_sector_buf(void) +{ + return (void *)CONFIG_FASTBOOT_BUF_ADDR; +} + +static inline bool is_buf_unaligned(void *buffer) +{ + return (bool)((uintptr_t)buffer % ALLOWED_BUF_ALIGN); +} + +static inline int get_boot_device(AvbOps *ops) +{ + struct AvbOpsData *data; + + if (ops) { + data = ops->user_data; + if (data) + return data->mmc_dev; + } + + return -1; +} + +#endif /* _AVB_VERIFY_H */