[Libguestfs] [PATCH nbdkit 1/4] partition: Move MBR and GPT parsing code to separate files.

Simply code motion, there should be no change to the functionality. --- filters/partition/partition.h | 48 ++++++++++ filters/partition/partition-gpt.c | 126 ++++++++++++++++++++++++++ filters/partition/partition-mbr.c | 91 +++++++++++++++++++ filters/partition/partition.c | 146 +++--------------------------- filters/partition/Makefile.am | 5 +- 5 files changed, 280 insertions(+), 136 deletions(-) diff --git a/filters/partition/partition.h b/filters/partition/partition.h new file mode 100644 index 0000000..f82d845 --- /dev/null +++ b/filters/partition/partition.h @@ -0,0 +1,48 @@ +/* nbdkit + * Copyright (C) 2018-2019 Red Hat Inc. + * 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 Red Hat 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 BY RED HAT AND CONTRIBUTORS ''AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, + * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A + * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RED HAT 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. + */ + +#ifndef NBDKIT_PARTITION_H +#define NBDKIT_PARTITION_H + +#include <nbdkit-filter.h> + +extern int partnum; + +extern int find_mbr_partition (struct nbdkit_next_ops *next_ops, void *nxdata, + int64_t size, uint8_t *mbr, + int64_t *offset_r, int64_t *range_r); +extern int find_gpt_partition (struct nbdkit_next_ops *next_ops, void *nxdata, + int64_t size, uint8_t *header_bytes, + int64_t *offset_r, int64_t *range_r); + +#endif /* NBDKIT_PARTITION_H */ diff --git a/filters/partition/partition-gpt.c b/filters/partition/partition-gpt.c new file mode 100644 index 0000000..feefe7b --- /dev/null +++ b/filters/partition/partition-gpt.c @@ -0,0 +1,126 @@ +/* nbdkit + * Copyright (C) 2018-2019 Red Hat Inc. + * 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 Red Hat 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 BY RED HAT AND CONTRIBUTORS ''AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, + * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A + * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RED HAT 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 <config.h> + +#include <stdio.h> +#include <stdlib.h> +#include <stdint.h> +#include <string.h> + +#include <nbdkit-filter.h> + +#include "byte-swapping.h" + +#include "partition.h" + +struct gpt_header { + uint32_t nr_partitions; + uint32_t partition_entry_size; +}; + +static void +get_gpt_header (uint8_t *sector, struct gpt_header *header) +{ + memcpy (&header->nr_partitions, &sector[0x50], 4); + header->nr_partitions = le32toh (header->nr_partitions); + memcpy (&header->partition_entry_size, &sector[0x54], 4); + header->partition_entry_size = le32toh (header->partition_entry_size); +} + +struct gpt_partition { + uint8_t partition_type_guid[16]; + uint64_t first_lba; + uint64_t last_lba; +}; + +static void +get_gpt_partition (uint8_t *bytes, struct gpt_partition *part) +{ + memcpy (&part->partition_type_guid, &bytes[0], 16); + memcpy (&part->first_lba, &bytes[0x20], 8); + part->first_lba = le64toh (part->first_lba); + memcpy (&part->last_lba, &bytes[0x28], 8); + part->last_lba = le64toh (part->last_lba); +} + +int +find_gpt_partition (struct nbdkit_next_ops *next_ops, void *nxdata, + int64_t size, uint8_t *header_bytes, + int64_t *offset_r, int64_t *range_r) +{ + uint8_t partition_bytes[128]; + struct gpt_header header; + struct gpt_partition partition; + int i; + int err; + + get_gpt_header (header_bytes, &header); + if (partnum > header.nr_partitions) { + nbdkit_error ("GPT partition number out of range"); + return -1; + } + + if (header.partition_entry_size < 128) { + nbdkit_error ("GPT partition entry size is < 128 bytes"); + return -1; + } + + /* Check the disk is large enough to contain the partition table + * array (twice) plus other GPT overheads. Otherwise it is likely + * that the GPT header is bogus. + */ + if (size < INT64_C(3*512) + + INT64_C(2) * header.nr_partitions * header.partition_entry_size) { + nbdkit_error ("GPT partition table is too large for this disk"); + return -1; + } + + for (i = 0; i < header.nr_partitions; ++i) { + /* We already checked these are within bounds above. */ + if (next_ops->pread (nxdata, partition_bytes, sizeof partition_bytes, + 2*512 + i*header.partition_entry_size, 0, &err) == -1) + return -1; + get_gpt_partition (partition_bytes, &partition); + if (memcmp (partition.partition_type_guid, + "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0", 16) != 0 && + partnum == i+1) { + *offset_r = partition.first_lba * 512; + *range_r = (1 + partition.last_lba - partition.first_lba) * 512; + return 0; + } + } + + nbdkit_error ("GPT partition %d not found", partnum); + return -1; +} diff --git a/filters/partition/partition-mbr.c b/filters/partition/partition-mbr.c new file mode 100644 index 0000000..f679db0 --- /dev/null +++ b/filters/partition/partition-mbr.c @@ -0,0 +1,91 @@ +/* nbdkit + * Copyright (C) 2018-2019 Red Hat Inc. + * 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 Red Hat 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 BY RED HAT AND CONTRIBUTORS ''AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, + * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A + * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RED HAT 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 <config.h> + +#include <stdio.h> +#include <stdlib.h> +#include <stdint.h> +#include <string.h> + +#include <nbdkit-filter.h> + +#include "byte-swapping.h" + +#include "partition.h" + +struct mbr_partition { + uint8_t part_type_byte; + uint32_t start_sector; + uint32_t nr_sectors; +}; + +static void +get_mbr_partition (uint8_t *sector, int i, struct mbr_partition *part) +{ + int offset = 0x1BE + i*0x10; + + part->part_type_byte = sector[offset+4]; + memcpy (&part->start_sector, &sector[offset+8], 4); + part->start_sector = le32toh (part->start_sector); + memcpy (&part->nr_sectors, &sector[offset+0xC], 4); + part->nr_sectors = le32toh (part->nr_sectors); +} + +int +find_mbr_partition (struct nbdkit_next_ops *next_ops, void *nxdata, + int64_t size, uint8_t *mbr, + int64_t *offset_r, int64_t *range_r) +{ + int i; + struct mbr_partition partition; + + if (partnum > 4) { + nbdkit_error ("MBR logical partitions are not supported"); + return -1; + } + + for (i = 0; i < 4; ++i) { + get_mbr_partition (mbr, i, &partition); + if (partition.nr_sectors > 0 && + partition.part_type_byte != 0 && + partnum == i+1) { + *offset_r = partition.start_sector * 512; + *range_r = partition.nr_sectors * 512; + return 0; + } + } + + nbdkit_error ("MBR partition %d not found", partnum); + return -1; +} diff --git a/filters/partition/partition.c b/filters/partition/partition.c index 4d141ef..af103a8 100644 --- a/filters/partition/partition.c +++ b/filters/partition/partition.c @@ -1,5 +1,5 @@ /* nbdkit - * Copyright (C) 2018 Red Hat Inc. + * Copyright (C) 2018-2019 Red Hat Inc. * All rights reserved. * * Redistribution and use in source and binary forms, with or without @@ -43,9 +43,11 @@ #include "byte-swapping.h" +#include "partition.h" + #define THREAD_MODEL NBDKIT_THREAD_MODEL_PARALLEL -static int partnum = -1; +int partnum = -1; /* Called for each key=value passed on the command line. */ static int @@ -111,134 +113,6 @@ partition_close (void *handle) free (h); } -/* Inspect the underlying partition table. partition_prepare is - * called before data processing. - */ -struct mbr_partition { - uint8_t part_type_byte; - uint32_t start_sector; - uint32_t nr_sectors; -}; - -static void -get_mbr_partition (uint8_t *sector, int i, struct mbr_partition *part) -{ - int offset = 0x1BE + i*0x10; - - part->part_type_byte = sector[offset+4]; - memcpy (&part->start_sector, &sector[offset+8], 4); - part->start_sector = le32toh (part->start_sector); - memcpy (&part->nr_sectors, &sector[offset+0xC], 4); - part->nr_sectors = le32toh (part->nr_sectors); -} - -static int -find_mbr_partition (struct nbdkit_next_ops *next_ops, void *nxdata, - struct handle *h, int64_t size, uint8_t *mbr) -{ - int i; - struct mbr_partition partition; - - if (partnum > 4) { - nbdkit_error ("MBR logical partitions are not supported"); - return -1; - } - - for (i = 0; i < 4; ++i) { - get_mbr_partition (mbr, i, &partition); - if (partition.nr_sectors > 0 && - partition.part_type_byte != 0 && - partnum == i+1) { - h->offset = partition.start_sector * 512; - h->range = partition.nr_sectors * 512; - return 0; - } - } - - nbdkit_error ("MBR partition %d not found", partnum); - return -1; -} - -struct gpt_header { - uint32_t nr_partitions; - uint32_t partition_entry_size; -}; - -static void -get_gpt_header (uint8_t *sector, struct gpt_header *header) -{ - memcpy (&header->nr_partitions, &sector[0x50], 4); - header->nr_partitions = le32toh (header->nr_partitions); - memcpy (&header->partition_entry_size, &sector[0x54], 4); - header->partition_entry_size = le32toh (header->partition_entry_size); -} - -struct gpt_partition { - uint8_t partition_type_guid[16]; - uint64_t first_lba; - uint64_t last_lba; -}; - -static void -get_gpt_partition (uint8_t *bytes, struct gpt_partition *part) -{ - memcpy (&part->partition_type_guid, &bytes[0], 16); - memcpy (&part->first_lba, &bytes[0x20], 8); - part->first_lba = le64toh (part->first_lba); - memcpy (&part->last_lba, &bytes[0x28], 8); - part->last_lba = le64toh (part->last_lba); -} - -static int -find_gpt_partition (struct nbdkit_next_ops *next_ops, void *nxdata, - struct handle *h, int64_t size, uint8_t *header_bytes) -{ - uint8_t partition_bytes[128]; - struct gpt_header header; - struct gpt_partition partition; - int i; - int err; - - get_gpt_header (header_bytes, &header); - if (partnum > header.nr_partitions) { - nbdkit_error ("GPT partition number out of range"); - return -1; - } - - if (header.partition_entry_size < 128) { - nbdkit_error ("GPT partition entry size is < 128 bytes"); - return -1; - } - - /* Check the disk is large enough to contain the partition table - * array (twice) plus other GPT overheads. Otherwise it is likely - * that the GPT header is bogus. - */ - if (size < INT64_C(3*512) + - INT64_C(2) * header.nr_partitions * header.partition_entry_size) { - nbdkit_error ("GPT partition table is too large for this disk"); - return -1; - } - - for (i = 0; i < header.nr_partitions; ++i) { - /* We already checked these are within bounds above. */ - if (next_ops->pread (nxdata, partition_bytes, sizeof partition_bytes, - 2*512 + i*header.partition_entry_size, 0, &err) == -1) - return -1; - get_gpt_partition (partition_bytes, &partition); - if (memcmp (partition.partition_type_guid, - "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0", 16) != 0 && - partnum == i+1) { - h->offset = partition.first_lba * 512; - h->range = (1 + partition.last_lba - partition.first_lba) * 512; - return 0; - } - } - - nbdkit_error ("GPT partition %d not found", partnum); - return -1; -} - static int partition_prepare (struct nbdkit_next_ops *next_ops, void *nxdata, void *handle) @@ -264,10 +138,12 @@ partition_prepare (struct nbdkit_next_ops *next_ops, void *nxdata, /* Is it GPT? */ if (size >= 2 * 34 * 512 && memcmp (&lba01[512], "EFI PART", 8) == 0) - r = find_gpt_partition (next_ops, nxdata, h, size, &lba01[512]); + r = find_gpt_partition (next_ops, nxdata, size, &lba01[512], + &h->offset, &h->range); /* Is it MBR? */ else if (lba01[0x1fe] == 0x55 && lba01[0x1ff] == 0xAA) - r = find_mbr_partition (next_ops, nxdata, h, size, lba01); + r = find_mbr_partition (next_ops, nxdata, size, lba01, + &h->offset, &h->range); else { nbdkit_error ("disk does not contain MBR or GPT partition table signature"); r = -1; @@ -275,9 +151,9 @@ partition_prepare (struct nbdkit_next_ops *next_ops, void *nxdata, if (r == -1) return -1; - /* The find_*_partition functions set h->offset & h->range in the - * handle to point to the partition boundaries. However we - * additionally check that they are inside the underlying disk. + /* The find_*_partition functions set h->offset & h->range to the + * partition boundaries. We additionally check that they are inside + * the underlying disk. */ if (h->offset < 0 || h->range < 0 || h->offset + h->range > size) { nbdkit_error ("partition is outside the disk"); diff --git a/filters/partition/Makefile.am b/filters/partition/Makefile.am index 7e8430a..0932793 100644 --- a/filters/partition/Makefile.am +++ b/filters/partition/Makefile.am @@ -1,5 +1,5 @@ # nbdkit -# Copyright (C) 2018 Red Hat Inc. +# Copyright (C) 2018-2019 Red Hat Inc. # All rights reserved. # # Redistribution and use in source and binary forms, with or without @@ -38,6 +38,9 @@ filter_LTLIBRARIES = nbdkit-partition-filter.la nbdkit_partition_filter_la_SOURCES = \ partition.c \ + partition.h \ + partition-gpt.c \ + partition-mbr.c \ $(top_srcdir)/include/nbdkit-filter.h nbdkit_partition_filter_la_CPPFLAGS = \ -- 2.20.1