commit 62b55300cfa6e9477329f71d20f7995e94fc88f1
parent 01fc835e641bb9fefbfbc51f6e070ca276328e69
Author: Brian Swetland <swetland@frotz.net>
Date: Sun, 15 Dec 2013 23:06:29 -0800
various small changes and enhancements
- allow writing to a normal file as well as block devices
- write the secondary GPT
- include linux, linux-swap, and efi-boot uuids
- =<type> suffix allows specification of partition type uuid
- tweak the bogus mbr values
- disable safety-check on sda/sdb
Diffstat:
| M | gpttool.c | | | 126 | +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++------------------ |
1 file changed, 98 insertions(+), 28 deletions(-)
diff --git a/gpttool.c b/gpttool.c
@@ -21,22 +21,38 @@
#include <string.h>
#include <fcntl.h>
-#include <zlib.h>
-
#include <linux/fs.h>
-
#include <sys/stat.h>
+#include <sys/ioctl.h>
+
+#include <zlib.h>
typedef unsigned char u8;
typedef unsigned short u16;
typedef unsigned int u32;
typedef unsigned long long u64;
+#define _crc32(ptr,len) crc32(crc32(0,Z_NULL,0),(void*)(ptr),len)
+
const u8 partition_type_uuid[16] = {
0xa2, 0xa0, 0xd0, 0xeb, 0xe5, 0xb9, 0x33, 0x44,
0x87, 0xc0, 0x68, 0xb6, 0xb7, 0x26, 0x99, 0xc7,
};
+const u8 partition_type_efi[16] = {
+ 0x28, 0x73, 0x2a, 0xc1, 0x1f, 0xf8, 0xd2, 0x11,
+ 0xba, 0x4b, 0x00, 0xa0, 0xc9, 0x3e, 0xc9, 0x3b,
+};
+
+const u8 partition_type_linux[16] = {
+ 0xa2, 0xa0, 0xd0, 0xeb, 0xe5, 0xb9, 0x33, 0x44,
+ 0x87, 0xc0, 0x68, 0xb6, 0xb7, 0x26, 0x99, 0xc7,
+};
+
+const u8 partition_type_swap[16] = {
+ 0x6d, 0xfd, 0x57, 0x06, 0xab, 0xa4, 0xc4, 0x43,
+ 0x84, 0xe5, 0x09, 0x33, 0xc8, 0x4b, 0x4f, 0x4f,
+};
#define EFI_VERSION 0x00010000
#define EFI_MAGIC "EFI PART"
@@ -95,12 +111,12 @@ void get_uuid(u8 *uuid)
void init_mbr(u8 *mbr, u32 blocks)
{
mbr[0x1be] = 0x00; // nonbootable
- mbr[0x1bf] = 0xFF; // bogus CHS
- mbr[0x1c0] = 0xFF;
- mbr[0x1c1] = 0xFF;
+ mbr[0x1bf] = 0x00; // bogus CHS
+ mbr[0x1c0] = 0x01;
+ mbr[0x1c1] = 0x00;
mbr[0x1c2] = 0xEE; // GPT partition
- mbr[0x1c3] = 0xFF; // bogus CHS
+ mbr[0x1c3] = 0xFE; // bogus CHS
mbr[0x1c4] = 0xFF;
mbr[0x1c5] = 0xFF;
@@ -115,7 +131,7 @@ void init_mbr(u8 *mbr, u32 blocks)
mbr[0x1ff] = 0xaa;
}
-int add_ptn(struct ptable *ptbl, u64 first, u64 last, const char *name)
+int add_ptn(struct ptable *ptbl, u64 first, u64 last, const char *name, const u8 *type)
{
struct efi_header *hdr = &ptbl->header;
struct efi_entry *entry = ptbl->entry;
@@ -133,7 +149,7 @@ int add_ptn(struct ptable *ptbl, u64 first, u64 last, const char *name)
for (n = 0; n < EFI_ENTRIES; n++, entry++) {
if (entry->type_uuid[0])
continue;
- memcpy(entry->type_uuid, partition_type_uuid, 16);
+ memcpy(entry->type_uuid, type, 16);
get_uuid(entry->uniq_uuid);
entry->first_lba = first;
entry->last_lba = last;
@@ -152,7 +168,8 @@ int usage(void)
" gpttool read <disk>\n"
" gpttool test [ <partition> ]*\n"
"\n"
- "partition: [<name>]:<size>[kmg] | @<file-of-partitions>\n"
+ "partition: [<name>]:<size>[kmg][=linux|=swap|=efi]\n"
+ " or: @<file-of-partitions>\n"
);
return 0;
}
@@ -217,7 +234,9 @@ u64 parse_size(char *sz)
int parse_ptn(struct ptable *ptbl, char *x)
{
+ const u8 *type = partition_type_uuid;
char *y = strchr(x, ':');
+ char *z;
u64 sz;
if (!y) {
@@ -226,6 +245,17 @@ int parse_ptn(struct ptable *ptbl, char *x)
}
*y++ = 0;
+ z = strchr(y, '=');
+ if (z) {
+ *z++ = 0;
+ if (!strcmp(z, "efi")) {
+ type = partition_type_efi;
+ } else if (!strcmp(z, "linux")) {
+ type = partition_type_linux;
+ } else if (!strcmp(z, "swap")) {
+ type = partition_type_swap;
+ }
+ }
if (*y == 0) {
sz = ptbl->header.last_lba - next_lba;
} else {
@@ -242,22 +272,32 @@ int parse_ptn(struct ptable *ptbl, char *x)
return -1;
}
- if (x[0] && add_ptn(ptbl, next_lba, next_lba + sz - 1, x))
+ if (x[0] && add_ptn(ptbl, next_lba, next_lba + sz - 1, x, type))
return -1;
next_lba = next_lba + sz;
return 0;
}
+void update_crc32(struct ptable *ptbl) {
+ u32 n;
+
+
+ n = _crc32((void*) ptbl->entry, sizeof(ptbl->entry));
+ ptbl->header.entries_crc32 = n;
+
+ ptbl->header.crc32 = 0;
+ n = _crc32((void*) &ptbl->header, sizeof(ptbl->header));
+ ptbl->header.crc32 = n;
+}
+
int main(int argc, char **argv)
{
struct ptable ptbl;
- struct efi_entry *entry;
struct efi_header *hdr = &ptbl.header;
struct stat s;
- u32 n;
- u64 sz, blk;
- int fd;
+ u64 sz;
+ int fd = -1;
const char *device;
int real_disk = 0;
@@ -282,18 +322,29 @@ int main(int argc, char **argv)
}
if (real_disk) {
+#if 0
if (!strcmp(device, "/dev/sda") ||
!strcmp(device, "/dev/sdb")) {
fprintf(stderr,"error: refusing to partition sda or sdb\n");
return -1;
}
-
+#endif
fd = open(device, O_RDWR);
if (fd < 0) {
fprintf(stderr,"error: cannot open '%s'\n", device);
return -1;
}
- if (ioctl(fd, BLKGETSIZE64, &sz)) {
+ if (fstat(fd, &s)) {
+ fprintf(stderr,"error: cannot stat '%s'\n", device);
+ return -1;
+ }
+ if (!S_ISBLK(s.st_mode) && !S_ISCHR(s.st_mode)) {
+ sz = s.st_size;
+ if (sz & 511) {
+ fprintf(stderr,"error: file size not multiple of 512\n");
+ return -1;
+ }
+ } else if (ioctl(fd, BLKGETSIZE64, &sz)) {
fprintf(stderr,"error: cannot query block device size\n");
return -1;
}
@@ -311,7 +362,7 @@ int main(int argc, char **argv)
hdr->header_lba = 1;
hdr->backup_lba = sz - 1;
hdr->first_lba = 34;
- hdr->last_lba = sz - 1;
+ hdr->last_lba = sz - 33;
get_uuid(hdr->volume_uuid);
hdr->entries_lba = 2;
hdr->entries_count = 128;
@@ -353,24 +404,43 @@ int main(int argc, char **argv)
argv++;
}
- n = crc32(0, Z_NULL, 0);
- n = crc32(n, (void*) ptbl.entry, sizeof(ptbl.entry));
- hdr->entries_crc32 = n;
-
- n = crc32(0, Z_NULL, 0);
- n = crc32(n, (void*) &ptbl.header, sizeof(ptbl.header));
- hdr->crc32 = n;
+ update_crc32(&ptbl);
show(&ptbl);
if (real_disk) {
- write(fd, &ptbl, sizeof(ptbl));
+ u64 off = (sz - 33) * 512;
+ if (write(fd, &ptbl, sizeof(ptbl)) != sizeof(ptbl)) {
+ fprintf(stderr,"error writing primary partition table\n");
+ return -1;
+ }
+ if (lseek(fd, off, SEEK_SET) != off) {
+ fprintf(stderr,"error seeking to secondary partition table\n");
+ return -1;
+ }
+
+ /* reverse these for the secondary copy */
+ hdr->header_lba = sz -1;
+ hdr->backup_lba = 1;
+ update_crc32(&ptbl);
+
+ if (write(fd, &ptbl.entry, sizeof(ptbl) - 1024) != (sizeof(ptbl) - 1024)) {
+ fprintf(stderr,"error writing secondary partition table\n");
+ return -1;
+ }
+ if (write(fd, &ptbl.header, 512) != 512) {
+ fprintf(stderr,"error writing secondary partition header\n");
+ return -1;
+ }
fsync(fd);
if (ioctl(fd, BLKRRPART, 0)) {
- fprintf(stderr,"could not re-read partition table\n");
+ fprintf(stderr,"warning: could not re-read partition table\n");
+ }
+ if (close(fd)) {
+ fprintf(stderr,"error writing data\n");
+ return -1;
}
- close(fd);
}
return 0;
}
