| // Copyright 2019 The Fuchsia Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "mbr.h" |
| |
| #include <endian.h> |
| #include <inttypes.h> |
| #include <lib/ddk/debug.h> |
| #include <string.h> |
| #include <zircon/compiler.h> |
| #include <zircon/errors.h> |
| #include <zircon/status.h> |
| #include <zircon/types.h> |
| |
| namespace mbr { |
| |
| zx_status_t Parse(const uint8_t* buffer, size_t bufsz, Mbr* out) { |
| if (bufsz < kMbrSize) { |
| return ZX_ERR_BUFFER_TOO_SMALL; |
| } |
| // Check the boot signature first to sanity-check that the buffer looks like |
| // an MBR header. |
| uint16_t boot_signature = |
| le16toh(*reinterpret_cast<const uint16_t*>(buffer + offsetof(Mbr, boot_signature))); |
| if (boot_signature != kMbrBootSignature) { |
| zxlogf(ERROR, "mbr: invalid mbr boot signature, expected 0x%04x got 0x%04x", kMbrBootSignature, |
| boot_signature); |
| return ZX_ERR_NOT_SUPPORTED; |
| } |
| memcpy(out, buffer, kMbrSize); |
| // Correct endian-sensitive fields |
| out->boot_signature = le16toh(out->boot_signature); |
| for (auto& partition : out->partitions) { |
| partition.start_sector_lba = le32toh(partition.start_sector_lba); |
| partition.num_sectors = le32toh(partition.num_sectors); |
| } |
| return ZX_OK; |
| } |
| |
| } // namespace mbr |
