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-rw-r--r--partx/gpt.c630
1 files changed, 630 insertions, 0 deletions
diff --git a/partx/gpt.c b/partx/gpt.c
new file mode 100644
index 000000000..bf90fdeb3
--- /dev/null
+++ b/partx/gpt.c
@@ -0,0 +1,630 @@
+/*
+ gpt.[ch]
+
+ Copyright (C) 2000-2001 Dell Computer Corporation <Matt_Domsch@dell.com>
+
+ EFI GUID Partition Table handling
+ Per Intel EFI Specification v1.02
+ http://developer.intel.com/technology/efi/efi.htm
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+*/
+
+#define _FILE_OFFSET_BITS 64
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <inttypes.h>
+#include <sys/stat.h>
+#include <sys/ioctl.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <errno.h>
+#include <asm/byteorder.h>
+#include "crc32.h"
+#include "gpt.h"
+#include "partx.h"
+
+#define BLKGETLASTSECT _IO(0x12,108) /* get last sector of block device */
+#define BLKGETSIZE _IO(0x12,96) /* return device size */
+#define BLKSSZGET _IO(0x12,104) /* get block device sector size */
+#define BLKGETSIZE64 _IOR(0x12,114,sizeof(uint64_t)) /* return device size in bytes (u64 *arg) */
+
+struct blkdev_ioctl_param {
+ unsigned int block;
+ size_t content_length;
+ char * block_contents;
+};
+
+/**
+ * efi_crc32() - EFI version of crc32 function
+ * @buf: buffer to calculate crc32 of
+ * @len - length of buf
+ *
+ * Description: Returns EFI-style CRC32 value for @buf
+ *
+ * This function uses the little endian Ethernet polynomial
+ * but seeds the function with ~0, and xor's with ~0 at the end.
+ * Note, the EFI Specification, v1.02, has a reference to
+ * Dr. Dobbs Journal, May 1994 (actually it's in May 1992).
+ */
+static inline uint32_t
+efi_crc32(const void *buf, unsigned long len)
+{
+ return (crc32(~0L, buf, len) ^ ~0L);
+}
+
+/**
+ * is_pmbr_valid(): test Protective MBR for validity
+ * @mbr: pointer to a legacy mbr structure
+ *
+ * Description: Returns 1 if PMBR is valid, 0 otherwise.
+ * Validity depends on two things:
+ * 1) MSDOS signature is in the last two bytes of the MBR
+ * 2) One partition of type 0xEE is found
+ */
+static int
+is_pmbr_valid(legacy_mbr *mbr)
+{
+ int i, found = 0, signature = 0;
+ if (!mbr)
+ return 0;
+ signature = (__le16_to_cpu(mbr->signature) == MSDOS_MBR_SIGNATURE);
+ for (i = 0; signature && i < 4; i++) {
+ if (mbr->partition[i].sys_type ==
+ EFI_PMBR_OSTYPE_EFI_GPT) {
+ found = 1;
+ break;
+ }
+ }
+ return (signature && found);
+}
+
+
+/************************************************************
+ * get_sector_size
+ * Requires:
+ * - filedes is an open file descriptor, suitable for reading
+ * Modifies: nothing
+ * Returns:
+ * sector size, or 512.
+ ************************************************************/
+static int
+get_sector_size(int filedes)
+{
+ int rc, sector_size = 512;
+
+ rc = ioctl(filedes, BLKSSZGET, &sector_size);
+ if (rc)
+ sector_size = 512;
+ return sector_size;
+}
+
+/************************************************************
+ * _get_num_sectors
+ * Requires:
+ * - filedes is an open file descriptor, suitable for reading
+ * Modifies: nothing
+ * Returns:
+ * Last LBA value on success
+ * 0 on error
+ *
+ * Try getting BLKGETSIZE64 and BLKSSZGET first,
+ * then BLKGETSIZE if necessary.
+ * Kernels 2.4.15-2.4.18 and 2.5.0-2.5.3 have a broken BLKGETSIZE64
+ * which returns the number of 512-byte sectors, not the size of
+ * the disk in bytes. Fixed in kernels 2.4.18-pre8 and 2.5.4-pre3.
+ ************************************************************/
+static uint64_t
+_get_num_sectors(int filedes)
+{
+ unsigned long sectors=0;
+ int rc;
+#if 0
+ uint64_t bytes=0;
+
+ rc = ioctl(filedes, BLKGETSIZE64, &bytes);
+ if (!rc)
+ return bytes / get_sector_size(filedes);
+#endif
+ rc = ioctl(filedes, BLKGETSIZE, &sectors);
+ if (rc)
+ return 0;
+
+ return sectors;
+}
+
+/************************************************************
+ * last_lba(): return number of last logical block of device
+ *
+ * @fd
+ *
+ * Description: returns Last LBA value on success, 0 on error.
+ * Notes: The value st_blocks gives the size of the file
+ * in 512-byte blocks, which is OK if
+ * EFI_BLOCK_SIZE_SHIFT == 9.
+ ************************************************************/
+
+static uint64_t
+last_lba(int filedes)
+{
+ int rc;
+ uint64_t sectors = 0;
+ struct stat s;
+ memset(&s, 0, sizeof (s));
+ rc = fstat(filedes, &s);
+ if (rc == -1) {
+ fprintf(stderr, "last_lba() could not stat: %s\n",
+ strerror(errno));
+ return 0;
+ }
+
+ if (S_ISBLK(s.st_mode)) {
+ sectors = _get_num_sectors(filedes);
+ } else {
+ fprintf(stderr,
+ "last_lba(): I don't know how to handle files with mode %x\n",
+ s.st_mode);
+ sectors = 1;
+ }
+
+ return sectors - 1;
+}
+
+
+static ssize_t
+read_lastoddsector(int fd, uint64_t lba, void *buffer, size_t count)
+{
+ int rc;
+ struct blkdev_ioctl_param ioctl_param;
+
+ if (!buffer) return 0;
+
+ ioctl_param.block = 0; /* read the last sector */
+ ioctl_param.content_length = count;
+ ioctl_param.block_contents = buffer;
+
+ rc = ioctl(fd, BLKGETLASTSECT, &ioctl_param);
+ if (rc == -1) perror("read failed");
+
+ return !rc;
+}
+
+static ssize_t
+read_lba(int fd, uint64_t lba, void *buffer, size_t bytes)
+{
+ int sector_size = get_sector_size(fd);
+ off_t offset = lba * sector_size;
+ ssize_t bytesread;
+
+ lseek(fd, offset, SEEK_SET);
+ bytesread = read(fd, buffer, bytes);
+
+ /* Kludge. This is necessary to read/write the last
+ block of an odd-sized disk, until Linux 2.5.x kernel fixes.
+ This is only used by gpt.c, and only to read
+ one sector, so we don't have to be fancy.
+ */
+ if (!bytesread && !(last_lba(fd) & 1) && lba == last_lba(fd)) {
+ bytesread = read_lastoddsector(fd, lba, buffer, bytes);
+ }
+ return bytesread;
+}
+
+/**
+ * alloc_read_gpt_entries(): reads partition entries from disk
+ * @fd is an open file descriptor to the whole disk
+ * @gpt is a buffer into which the GPT will be put
+ * Description: Returns ptes on success, NULL on error.
+ * Allocates space for PTEs based on information found in @gpt.
+ * Notes: remember to free pte when you're done!
+ */
+static gpt_entry *
+alloc_read_gpt_entries(int fd, gpt_header * gpt)
+{
+ gpt_entry *pte;
+ size_t count = __le32_to_cpu(gpt->num_partition_entries) *
+ __le32_to_cpu(gpt->sizeof_partition_entry);
+
+ if (!count) return NULL;
+
+ pte = (gpt_entry *)malloc(count);
+ if (!pte)
+ return NULL;
+ memset(pte, 0, count);
+
+ if (!read_lba(fd, __le64_to_cpu(gpt->partition_entry_lba), pte,
+ count)) {
+ free(pte);
+ return NULL;
+ }
+ return pte;
+}
+
+/**
+ * alloc_read_gpt_header(): Allocates GPT header, reads into it from disk
+ * @fd is an open file descriptor to the whole disk
+ * @lba is the Logical Block Address of the partition table
+ *
+ * Description: returns GPT header on success, NULL on error. Allocates
+ * and fills a GPT header starting at @ from @bdev.
+ * Note: remember to free gpt when finished with it.
+ */
+static gpt_header *
+alloc_read_gpt_header(int fd, uint64_t lba)
+{
+ gpt_header *gpt;
+ gpt = (gpt_header *)
+ malloc(sizeof (gpt_header));
+ if (!gpt)
+ return NULL;
+ memset(gpt, 0, sizeof (*gpt));
+ if (!read_lba(fd, lba, gpt, sizeof (gpt_header))) {
+ free(gpt);
+ return NULL;
+ }
+
+ return gpt;
+}
+
+/**
+ * is_gpt_valid() - tests one GPT header and PTEs for validity
+ * @fd is an open file descriptor to the whole disk
+ * @lba is the logical block address of the GPT header to test
+ * @gpt is a GPT header ptr, filled on return.
+ * @ptes is a PTEs ptr, filled on return.
+ *
+ * Description: returns 1 if valid, 0 on error.
+ * If valid, returns pointers to newly allocated GPT header and PTEs.
+ */
+static int
+is_gpt_valid(int fd, uint64_t lba,
+ gpt_header ** gpt, gpt_entry ** ptes)
+{
+ int rc = 0; /* default to not valid */
+ uint32_t crc, origcrc;
+
+ if (!gpt || !ptes)
+ return 0;
+ if (!(*gpt = alloc_read_gpt_header(fd, lba)))
+ return 0;
+
+ /* Check the GUID Partition Table signature */
+ if (__le64_to_cpu((*gpt)->signature) != GPT_HEADER_SIGNATURE) {
+ /*
+ printf("GUID Partition Table Header signature is wrong: %" PRIx64" != %" PRIx64 "\n",
+ __le64_to_cpu((*gpt)->signature), GUID_PT_HEADER_SIGNATURE);
+ */
+ free(*gpt);
+ *gpt = NULL;
+ return rc;
+ }
+
+ /* Check the GUID Partition Table Header CRC */
+ origcrc = __le32_to_cpu((*gpt)->header_crc32);
+ (*gpt)->header_crc32 = 0;
+ crc = efi_crc32(*gpt, __le32_to_cpu((*gpt)->header_size));
+ if (crc != origcrc) {
+ // printf( "GPTH CRC check failed, %x != %x.\n", origcrc, crc);
+ (*gpt)->header_crc32 = __cpu_to_le32(origcrc);
+ free(*gpt);
+ *gpt = NULL;
+ return 0;
+ }
+ (*gpt)->header_crc32 = __cpu_to_le32(origcrc);
+
+ /* Check that the my_lba entry points to the LBA
+ * that contains the GPT we read */
+ if (__le64_to_cpu((*gpt)->my_lba) != lba) {
+ // printf( "my_lba % PRIx64 "x != lba %"PRIx64 "x.\n", __le64_to_cpu((*gpt)->my_lba), lba);
+ free(*gpt);
+ *gpt = NULL;
+ return 0;
+ }
+
+ if (!(*ptes = alloc_read_gpt_entries(fd, *gpt))) {
+ free(*gpt);
+ *gpt = NULL;
+ return 0;
+ }
+
+ /* Check the GUID Partition Entry Array CRC */
+ crc = efi_crc32(*ptes,
+ __le32_to_cpu((*gpt)->num_partition_entries) *
+ __le32_to_cpu((*gpt)->sizeof_partition_entry));
+ if (crc != __le32_to_cpu((*gpt)->partition_entry_array_crc32)) {
+ // printf("GUID Partitition Entry Array CRC check failed.\n");
+ free(*gpt);
+ *gpt = NULL;
+ free(*ptes);
+ *ptes = NULL;
+ return 0;
+ }
+
+ /* We're done, all's well */
+ return 1;
+}
+/**
+ * compare_gpts() - Search disk for valid GPT headers and PTEs
+ * @pgpt is the primary GPT header
+ * @agpt is the alternate GPT header
+ * @lastlba is the last LBA number
+ * Description: Returns nothing. Sanity checks pgpt and agpt fields
+ * and prints warnings on discrepancies.
+ *
+ */
+static void
+compare_gpts(gpt_header *pgpt, gpt_header *agpt, uint64_t lastlba)
+{
+ int error_found = 0;
+ if (!pgpt || !agpt)
+ return;
+ if (__le64_to_cpu(pgpt->my_lba) != __le64_to_cpu(agpt->alternate_lba)) {
+ fprintf(stderr,
+ "GPT:Primary header LBA != Alt. header alternate_lba\n");
+ fprintf(stderr, "GPT:%" PRIx64 "x != %" PRIx64 "x\n",
+ __le64_to_cpu(pgpt->my_lba),
+ __le64_to_cpu(agpt->alternate_lba));
+ error_found++;
+ }
+ if (__le64_to_cpu(pgpt->alternate_lba) != __le64_to_cpu(agpt->my_lba)) {
+ fprintf(stderr,
+ "GPT:Primary header alternate_lba != Alt. header my_lba\n");
+ fprintf(stderr, "GPT:%" PRIx64 " != %" PRIx64 "\n",
+ __le64_to_cpu(pgpt->alternate_lba),
+ __le64_to_cpu(agpt->my_lba));
+ error_found++;
+ }
+ if (__le64_to_cpu(pgpt->first_usable_lba) !=
+ __le64_to_cpu(agpt->first_usable_lba)) {
+ fprintf(stderr, "GPT:first_usable_lbas don't match.\n");
+ fprintf(stderr, "GPT:%" PRIx64 " != %" PRIx64 "\n",
+ __le64_to_cpu(pgpt->first_usable_lba),
+ __le64_to_cpu(agpt->first_usable_lba));
+ error_found++;
+ }
+ if (__le64_to_cpu(pgpt->last_usable_lba) !=
+ __le64_to_cpu(agpt->last_usable_lba)) {
+ fprintf(stderr, "GPT:last_usable_lbas don't match.\n");
+ fprintf(stderr, "GPT:%" PRIx64 " != %" PRIx64 "\n",
+ __le64_to_cpu(pgpt->last_usable_lba),
+ __le64_to_cpu(agpt->last_usable_lba));
+ error_found++;
+ }
+ if (efi_guidcmp(pgpt->disk_guid, agpt->disk_guid)) {
+ fprintf(stderr, "GPT:disk_guids don't match.\n");
+ error_found++;
+ }
+ if (__le32_to_cpu(pgpt->num_partition_entries) !=
+ __le32_to_cpu(agpt->num_partition_entries)) {
+ fprintf(stderr, "GPT:num_partition_entries don't match: "
+ "0x%x != 0x%x\n",
+ __le32_to_cpu(pgpt->num_partition_entries),
+ __le32_to_cpu(agpt->num_partition_entries));
+ error_found++;
+ }
+ if (__le32_to_cpu(pgpt->sizeof_partition_entry) !=
+ __le32_to_cpu(agpt->sizeof_partition_entry)) {
+ fprintf(stderr,
+ "GPT:sizeof_partition_entry values don't match: "
+ "0x%x != 0x%x\n",
+ __le32_to_cpu(pgpt->sizeof_partition_entry),
+ __le32_to_cpu(agpt->sizeof_partition_entry));
+ error_found++;
+ }
+ if (__le32_to_cpu(pgpt->partition_entry_array_crc32) !=
+ __le32_to_cpu(agpt->partition_entry_array_crc32)) {
+ fprintf(stderr,
+ "GPT:partition_entry_array_crc32 values don't match: "
+ "0x%x != 0x%x\n",
+ __le32_to_cpu(pgpt->partition_entry_array_crc32),
+ __le32_to_cpu(agpt->partition_entry_array_crc32));
+ error_found++;
+ }
+ if (__le64_to_cpu(pgpt->alternate_lba) != lastlba) {
+ fprintf(stderr,
+ "GPT:Primary header thinks Alt. header is not at the end of the disk.\n");
+ fprintf(stderr, "GPT:%" PRIx64 " != %" PRIx64 "\n",
+ __le64_to_cpu(pgpt->alternate_lba), lastlba);
+ error_found++;
+ }
+
+ if (__le64_to_cpu(agpt->my_lba) != lastlba) {
+ fprintf(stderr,
+ "GPT:Alternate GPT header not at the end of the disk.\n");
+ fprintf(stderr, "GPT:%" PRIx64 " != %" PRIx64 "\n",
+ __le64_to_cpu(agpt->my_lba), lastlba);
+ error_found++;
+ }
+
+ if (error_found)
+ fprintf(stderr,
+ "GPT: Use GNU Parted to correct GPT errors.\n");
+ return;
+}
+
+/**
+ * find_valid_gpt() - Search disk for valid GPT headers and PTEs
+ * @fd is an open file descriptor to the whole disk
+ * @gpt is a GPT header ptr, filled on return.
+ * @ptes is a PTEs ptr, filled on return.
+ * Description: Returns 1 if valid, 0 on error.
+ * If valid, returns pointers to newly allocated GPT header and PTEs.
+ * Validity depends on finding either the Primary GPT header and PTEs valid,
+ * or the Alternate GPT header and PTEs valid, and the PMBR valid.
+ */
+static int
+find_valid_gpt(int fd, gpt_header ** gpt, gpt_entry ** ptes)
+{
+ extern int force_gpt;
+ int good_pgpt = 0, good_agpt = 0, good_pmbr = 0;
+ gpt_header *pgpt = NULL, *agpt = NULL;
+ gpt_entry *pptes = NULL, *aptes = NULL;
+ legacy_mbr *legacymbr = NULL;
+ uint64_t lastlba;
+ if (!gpt || !ptes)
+ return 0;
+
+ lastlba = last_lba(fd);
+ good_pgpt = is_gpt_valid(fd, GPT_PRIMARY_PARTITION_TABLE_LBA,
+ &pgpt, &pptes);
+ if (good_pgpt) {
+ good_agpt = is_gpt_valid(fd,
+ __le64_to_cpu(pgpt->alternate_lba),
+ &agpt, &aptes);
+ if (!good_agpt) {
+ good_agpt = is_gpt_valid(fd, lastlba,
+ &agpt, &aptes);
+ }
+ }
+ else {
+ good_agpt = is_gpt_valid(fd, lastlba,
+ &agpt, &aptes);
+ }
+
+ /* The obviously unsuccessful case */
+ if (!good_pgpt && !good_agpt) {
+ goto fail;
+ }
+
+ /* This will be added to the EFI Spec. per Intel after v1.02. */
+ legacymbr = malloc(sizeof (*legacymbr));
+ if (legacymbr) {
+ memset(legacymbr, 0, sizeof (*legacymbr));
+ read_lba(fd, 0, (uint8_t *) legacymbr,
+ sizeof (*legacymbr));
+ good_pmbr = is_pmbr_valid(legacymbr);
+ free(legacymbr);
+ legacymbr=NULL;
+ }
+
+ /* Failure due to bad PMBR */
+ if ((good_pgpt || good_agpt) && !good_pmbr && !force_gpt) {
+ fprintf(stderr,
+ " Warning: Disk has a valid GPT signature "
+ "but invalid PMBR.\n"
+ " Assuming this disk is *not* a GPT disk anymore.\n"
+ " Use gpt kernel option to override. "
+ "Use GNU Parted to correct disk.\n");
+ goto fail;
+ }
+
+ /* Would fail due to bad PMBR, but force GPT anyhow */
+ if ((good_pgpt || good_agpt) && !good_pmbr && force_gpt) {
+ fprintf(stderr,
+ " Warning: Disk has a valid GPT signature but "
+ "invalid PMBR.\n"
+ " Use GNU Parted to correct disk.\n"
+ " gpt option taken, disk treated as GPT.\n");
+ }
+
+ compare_gpts(pgpt, agpt, lastlba);
+
+ /* The good cases */
+ if (good_pgpt && (good_pmbr || force_gpt)) {
+ *gpt = pgpt;
+ *ptes = pptes;
+ if (agpt) { free(agpt); agpt = NULL; }
+ if (aptes) { free(aptes); aptes = NULL; }
+ if (!good_agpt) {
+ fprintf(stderr,
+ "Alternate GPT is invalid, "
+ "using primary GPT.\n");
+ }
+ return 1;
+ }
+ else if (good_agpt && (good_pmbr || force_gpt)) {
+ *gpt = agpt;
+ *ptes = aptes;
+ if (pgpt) { free(pgpt); pgpt = NULL; }
+ if (pptes) { free(pptes); pptes = NULL; }
+ fprintf(stderr,
+ "Primary GPT is invalid, using alternate GPT.\n");
+ return 1;
+ }
+
+ fail:
+ if (pgpt) { free(pgpt); pgpt=NULL; }
+ if (agpt) { free(agpt); agpt=NULL; }
+ if (pptes) { free(pptes); pptes=NULL; }
+ if (aptes) { free(aptes); aptes=NULL; }
+ *gpt = NULL;
+ *ptes = NULL;
+ return 0;
+}
+
+/**
+ * read_gpt_pt()
+ * @fd
+ * @all - slice with start/size of whole disk
+ *
+ * 0 if this isn't our partition table
+ * number of partitions if successful
+ *
+ */
+int
+read_gpt_pt (int fd, struct slice all, struct slice *sp, int ns)
+{
+ gpt_header *gpt = NULL;
+ gpt_entry *ptes = NULL;
+ uint32_t i;
+ int n = 0;
+ int last_used_index=-1;
+
+ if (!find_valid_gpt (fd, &gpt, &ptes) || !gpt || !ptes) {
+ if (gpt)
+ free (gpt);
+ if (ptes)
+ free (ptes);
+ return 0;
+ }
+
+ for (i = 0; i < __le32_to_cpu(gpt->num_partition_entries) && i < ns; i++) {
+ if (!efi_guidcmp (NULL_GUID, ptes[i].partition_type_guid)) {
+ sp[n].start = 0;
+ sp[n].size = 0;
+ n++;
+ } else {
+ sp[n].start = __le64_to_cpu(ptes[i].starting_lba);
+ sp[n].size = __le64_to_cpu(ptes[i].ending_lba);
+ last_used_index=n;
+ n++;
+ }
+ }
+ free (ptes);
+ free (gpt);
+ return last_used_index+1;
+}
+
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only. This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-indent-level: 4
+ * c-brace-imaginary-offset: 0
+ * c-brace-offset: -4
+ * c-argdecl-indent: 4
+ * c-label-offset: -4
+ * c-continued-statement-offset: 4
+ * c-continued-brace-offset: 0
+ * indent-tabs-mode: nil
+ * tab-width: 8
+ * End:
+ */
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