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Richard W.M. Jones

2019-Jan-20 20:57 UTC

[Libguestfs] [PATCH nbdkit 0/4] partition: Support MBR logical partitions.

This implements support for MBR logical partitions in
nbdkit-partition-filter, complementing existing support in the
partitioning plugin.

Rich.

Richard W.M. Jones

2019-Jan-20 20:57 UTC

head link

[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

Richard W.M. Jones

2019-Jan-20 20:57 UTC

head link

[Libguestfs] [PATCH nbdkit 2/4] partition: Support MBR logical partitions.

---
 filters/partition/nbdkit-partition-filter.pod |   5 -
 filters/partition/partition-mbr.c             | 108 ++++++++++++++++--
 tests/test-partitioning1.sh                   |  22 +++-
 3 files changed, 117 insertions(+), 18 deletions(-)

diff --git a/filters/partition/nbdkit-partition-filter.pod
b/filters/partition/nbdkit-partition-filter.pod
index 4a615b6..ccd1b52 100644
--- a/filters/partition/nbdkit-partition-filter.pod
+++ b/filters/partition/nbdkit-partition-filter.pod
@@ -19,11 +19,6 @@ This works like the C<qemu-nbd -P> option.
 The opposite of this filter is L<nbdkit-partitioning-plugin(1)> which
 adds a virtual partition table to a file or files.
 
-=head1 NOTE
-
-Only MBR primary partitions and GPT partition tables are supported.
-MBR logical partitions are B<not> supported.
-
 =head1 PARAMETERS
 
 =over 4
diff --git a/filters/partition/partition-mbr.c
b/filters/partition/partition-mbr.c
index f679db0..8e61128 100644
--- a/filters/partition/partition-mbr.c
+++ b/filters/partition/partition-mbr.c
@@ -36,14 +36,20 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdint.h>
+#include <inttypes.h>
 #include <string.h>
+#include <errno.h>
 
 #include <nbdkit-filter.h>
 
 #include "byte-swapping.h"
+#include "isaligned.h"
 
 #include "partition.h"
 
+/* See also linux.git/block/partitions/msdos.c:is_extended_partition */
+#define is_extended(byte) ((byte) == 0x5 || (byte) == 0xf || (byte) == 0x85)
+
 struct mbr_partition {
   uint8_t part_type_byte;
   uint32_t start_sector;
@@ -69,20 +75,98 @@ find_mbr_partition (struct nbdkit_next_ops *next_ops, void
*nxdata,
 {
   int i;
   struct mbr_partition partition;
+  uint32_t ep_start_sector, ep_nr_sectors;
+  uint64_t ebr, next_ebr;
+  uint8_t sector[512];
 
-  if (partnum > 4) {
-    nbdkit_error ("MBR logical partitions are not supported");
+  if (partnum <= 4) {           /* Primary partition. */
+    for (i = 0; i < 4; ++i) {
+      get_mbr_partition (mbr, i, &partition);
+      if (partition.nr_sectors > 0 &&
+          partition.part_type_byte != 0 &&
+          !is_extended (partition.part_type_byte) &&
+          partnum == i+1) {
+        *offset_r = partition.start_sector * 512;
+        *range_r = partition.nr_sectors * 512;
+        return 0;
+      }
+    }
+  }
+  else {                        /* Logical partition. */
+    /* Find the extended partition. */
+    for (i = 0; i < 4; ++i) {
+      get_mbr_partition (mbr, i, &partition);
+      if (partition.nr_sectors > 0 &&
+          is_extended (partition.part_type_byte)) {
+        goto found_extended;
+      }
+    }
+    nbdkit_error ("MBR logical partition %d (>= 5) selected, but there
is no extended partition in the partition table",
+                  partnum);
     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;
+
+  found_extended:
+    ep_start_sector = partition.start_sector;
+    ep_nr_sectors = partition.nr_sectors;
+    ebr = ep_start_sector * UINT64_C(512);
+
+    /* This loop will terminate eventually because we only accept
+     * links which strictly increase the EBR pointer.
+     */
+    for (i = 5; ; ++i) {
+      /* Read the EBR sector. */
+      if (next_ops->pread (nxdata, sector, sizeof sector, ebr, 0,
+                           &errno) == -1)
+        return -1;
+
+      if (i == partnum) {
+        uint64_t offset, range;
+
+        /* First entry in EBR points to the logical partition. */
+        get_mbr_partition (sector, 0, &partition);
+
+        /* The first entry start sector is relative to the EBR. */
+        offset = ebr + partition.start_sector * UINT64_C(512);
+        range = partition.nr_sectors * UINT64_C(512);
+
+        /* Logical partition cannot be before the corresponding EBR,
+         * and it cannot extend beyond the enclosing extended
+         * partition.
+         */
+        if (offset <= ebr ||
+            offset + range >
+              ((uint64_t)ep_start_sector + ep_nr_sectors) * 512) {
+          nbdkit_error ("logical partition start or size out of range
"
+                        "(offset=%" PRIu64 ", range=%"
PRIu64 ", "
+                        "ep:startsect=%" PRIu32 ",
ep:nrsects=%" PRIu32 ")",
+                        offset, range, ep_start_sector, ep_nr_sectors);
+          return -1;
+        }
+        *offset_r = offset;
+        *range_r = range;
+        return 0;
+      }
+
+      /* Second entry in EBR links to the next EBR. */
+      get_mbr_partition (sector, 1, &partition);
+
+      /* All zeroes means the end of the chain. */
+      if (partition.start_sector == 0 && partition.nr_sectors == 0)
+        break;
+
+      /* The second entry start sector is relative to the start to the
+       * extended partition.
+       */
+      next_ebr = ((uint64_t)ep_start_sector + partition.start_sector) * 512;
+
+      /* Make sure the next EBR > current EBR. */
+      if (next_ebr <= ebr) {
+        nbdkit_error ("invalid EBR chain: "
+                      "next EBR %" PRIu64 " <= current EBR
%" PRIu64,
+                      next_ebr, ebr);
+        return -1;
+      }
+      ebr = next_ebr;
     }
   }
 
diff --git a/tests/test-partitioning1.sh b/tests/test-partitioning1.sh
index 76ab43b..8aa45b9 100755
--- a/tests/test-partitioning1.sh
+++ b/tests/test-partitioning1.sh
@@ -77,7 +77,27 @@ nbdkit -f -v -D partitioning.regions=1 -U - \
 # Contents of partitioning1.out should be identical to file-data.
 cmp file-data partitioning1.out
 
-# Same test with GPT and more partitions.
+# Same test with > 4 MBR partitions.
+# Note we select partition 6 because partition 4 is the extended partition.
+nbdkit -f -v -D partitioning.regions=1 -U - \
+       --filter=partition \
+       partitioning \
+       partitioning1-p1 \
+       partitioning1-p2 \
+       partitioning1-p3 \
+       partitioning1-p4 \
+       type-guid=A2A0D0EB-E5B9-3344-87C0-68B6B72699C7 \
+       file-data \
+       type-guid=AF3DC60F-8384-7247-8E79-3D69D8477DE4 \
+       partitioning1-p5 \
+       partitioning1-p6 \
+       partition-type=mbr \
+       partition=6 \
+       --run 'qemu-img convert $nbd partitioning1.out'
+
+cmp file-data partitioning1.out
+
+# Same test with GPT.
 nbdkit -f -v -D partitioning.regions=1 -U - \
        --filter=partition \
        partitioning \
-- 
2.20.1

Richard W.M. Jones

2019-Jan-20 20:57 UTC

head link

[Libguestfs] [PATCH nbdkit 3/4] tests: Copy test-partitioning4.sh for MBR.

This test is now applicable to MBR too since we started
supporting logical partitions.
---
 tests/Makefile.am           |  4 +-
 tests/test-partitioning4.sh |  2 +-
 tests/test-partitioning6.sh | 92 +++++++++++++++++++++++++++++++++++++
 3 files changed, 96 insertions(+), 2 deletions(-)

diff --git a/tests/Makefile.am b/tests/Makefile.am
index 27abbaf..3afa81a 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -84,6 +84,7 @@ EXTRA_DIST = \
 	test-partitioning3.sh \
 	test-partitioning4.sh \
 	test-partitioning5.sh \
+	test-partitioning6.sh \
 	test-pattern.sh \
 	test-pattern-largest.sh \
 	test-pattern-largest-for-qemu.sh \
@@ -453,7 +454,8 @@ test_memory_LDADD = libtest.la $(LIBGUESTFS_LIBS)
 # partitioning plugin test.
 TESTS += \
 	test-partitioning1.sh \
-	test-partitioning4.sh
+	test-partitioning4.sh \
+	test-partitioning6.sh
 if HAVE_GUESTFISH
 TESTS += \
 	test-partitioning2.sh \
diff --git a/tests/test-partitioning4.sh b/tests/test-partitioning4.sh
index 4177640..f80c7ae 100755
--- a/tests/test-partitioning4.sh
+++ b/tests/test-partitioning4.sh
@@ -33,7 +33,7 @@
 
 # Test the partitioning plugin.
 #
-# Test 4: Test > 128 partitions.
+# Test 4: Test > 128 partitions using GPT.
 #
 # virtio-scsi (used by libguestfs) doesn't support more than 15
 # partitions.  In fact the only client which supports this is our own
diff --git a/tests/test-partitioning6.sh b/tests/test-partitioning6.sh
new file mode 100755
index 0000000..ea84854
--- /dev/null
+++ b/tests/test-partitioning6.sh
@@ -0,0 +1,92 @@
+#!/usr/bin/env bash
+# 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.
+
+# Test the partitioning plugin.
+#
+# Test 4: Test > 128 partitions using MBR.
+#
+# virtio-scsi (used by libguestfs) doesn't support more than 15
+# partitions.  In fact the only client which supports this is our own
+# partition filter so we use that for the test.
+
+source ./functions.sh
+set -e
+set -x
+
+# Check if the printf utility is available.  This is probably using
+# the bash builtin (not the one from coreutils) which does not
+# understand --flags, so we have to test it using a dummy format
+# string.
+if ! printf ""; then
+    echo "$0: missing or broken printf"
+    exit 77
+fi
+
+# Test that qemu-img works
+if ! qemu-img --help >/dev/null; then
+    echo "$0: missing or broken qemu-img"
+    exit 77
+fi
+
+d=partitioning6.d
+rm -rf $d
+mkdir $d
+cleanup_fn rm -rf $d
+
+# Create the partitions.
+for i in {1..768}; do
+    truncate -s 1 $(printf '%s/part.%04d' $d $i)
+done
+
+# Create partition 250 containing data and truncate it to a whole
+# number of sectors.
+rm $d/part.0250
+for i in {0..1000}; do
+    echo -n "hello " >> $d/part.0250
+done
+truncate -s 6144 $d/part.0250
+
+# Run nbdkit.
+#
+# Note we select partition 251 (not 250) because partition 4 is the
+# extended partition and everything partition following moves up by 1.
+nbdkit -f -v -D partitioning.regions=1 -U - \
+             --filter=partition \
+             partitioning \
+             $d/part.* \
+             partition-type=mbr \
+             partition=251 \
+             --run "qemu-img convert \$nbd $d/out"
+
+# The output should be identical to partition 250.
+cmp $d/part.0250 $d/out
-- 
2.20.1

Richard W.M. Jones

2019-Jan-20 20:57 UTC

head link

[Libguestfs] [PATCH nbdkit 4/4] tests: Implement a better nbdkit-partition-filter test.

Test the partition filter against real life partition tables created
by sfdisk.
---
 tests/test-partition.c  | 101 -----------------------------
 tests/Makefile.am       |   7 +-
 tests/test-partition.sh | 140 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 142 insertions(+), 106 deletions(-)

diff --git a/tests/test-partition.c b/tests/test-partition.c
deleted file mode 100644
index 3de60d8..0000000
--- a/tests/test-partition.c
+++ /dev/null
@@ -1,101 +0,0 @@
-/* nbdkit
- * Copyright (C) 2018 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 <inttypes.h>
-#include <string.h>
-#include <unistd.h>
-
-#include <guestfs.h>
-
-#include "test.h"
-
-int
-main (int argc, char *argv[])
-{
-  guestfs_h *g;
-  int r;
-  char *data;
-
-  if (test_start_nbdkit ("-r",
-                         "--filter", "partition",
-                         "file", "disk",
-                         "partition=1",
-                         NULL) == -1)
-    exit (EXIT_FAILURE);
-
-  g = guestfs_create ();
-  if (g == NULL) {
-    perror ("guestfs_create");
-    exit (EXIT_FAILURE);
-  }
-
-  r = guestfs_add_drive_opts (g, "",
-                              GUESTFS_ADD_DRIVE_OPTS_READONLY, 1,
-                              GUESTFS_ADD_DRIVE_OPTS_FORMAT, "raw",
-                              GUESTFS_ADD_DRIVE_OPTS_PROTOCOL, "nbd",
-                              GUESTFS_ADD_DRIVE_OPTS_SERVER, server,
-                              -1);
-  if (r == -1)
-    exit (EXIT_FAILURE);
-
-  if (guestfs_launch (g) == -1)
-    exit (EXIT_FAILURE);
-
-  /* Because we're using the partition filter, the device should
-   * appear to be a filesystem directly on a whole disk.
-   */
-  if (guestfs_mount_ro (g, "/dev/sda", "/") == -1)
-    exit (EXIT_FAILURE);
-
-  data = guestfs_cat (g, "/hello.txt");
-  if (!data)
-    exit (EXIT_FAILURE);
-
-  if (strcmp (data, "hello,world") != 0) {
-    fprintf (stderr,
-             "%s FAILED: unexpected content of /hello.txt file "
-             "(actual: %s, expected: \"hello,world\")\n",
-             program_name, data);
-    exit (EXIT_FAILURE);
-  }
-
-  free (data);
-
-  guestfs_close (g);
-  exit (EXIT_SUCCESS);
-}
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 3afa81a..dfc065e 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -79,6 +79,7 @@ EXTRA_DIST = \
 	test-offset2.sh \
 	test-parallel-file.sh \
 	test-parallel-nbd.sh \
+	test-partition.sh \
 	test-partitioning1.sh \
 	test-partitioning2.sh \
 	test-partitioning3.sh \
@@ -794,11 +795,7 @@ test_offset_LDADD = libtest.la $(LIBGUESTFS_LIBS)
 TESTS += test-offset2.sh
 
 # partition filter test.
-LIBGUESTFS_TESTS += test-partition
-
-test_partition_SOURCES = test-partition.c test.h
-test_partition_CFLAGS = $(WARNINGS_CFLAGS) $(LIBGUESTFS_CFLAGS)
-test_partition_LDADD = libtest.la $(LIBGUESTFS_LIBS)
+TESTS += test-partition.sh
 
 # truncate filter tests.
 TESTS += \
diff --git a/tests/test-partition.sh b/tests/test-partition.sh
new file mode 100755
index 0000000..425cd0f
--- /dev/null
+++ b/tests/test-partition.sh
@@ -0,0 +1,140 @@
+#!/usr/bin/env bash
+# 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.
+
+source ./functions.sh
+set -e
+set -x
+
+d="partition.d"
+rm -rf $d
+cleanup_fn rm -rf $d
+mkdir $d
+
+# Test that sfdisk is available and working.
+if ! sfdisk --help >/dev/null; then
+    echo "$0: missing or broken sfdisk"
+    exit 77
+fi
+
+# Test that qemu-img is available and working.
+if ! qemu-img --help >/dev/null; then
+    echo "$0: missing or broken qemu-img"
+    exit 77
+fi
+
+echo "The quick brown fox jumps over the lazy dog" > $d/rand
+
+test ()
+{
+    label=$1
+    nrparts=$2
+
+    rm -f $d/disk
+    truncate -s 1G $d/disk
+    sfdisk -X $label $d/disk
+
+    # Run nbdkit on each partition, copying data in and out.
+    for ((part=1; part <= $nrparts; ++part)); do
+        if [ $nrparts -le 4 ] || [ $label != "dos" ] || [ $part -ne 4
]; then
+            nbdkit -f -v --filter=partition file $d/disk partition=$part \
+                   --run "qemu-img convert -n $d/rand \$nbd"
+            nbdkit -f -v --filter=partition file $d/disk partition=$part \
+                   --run "qemu-img convert \$nbd $d/out"
+            truncate -r $d/rand $d/out
+            cmp $d/rand $d/out
+        fi
+    done
+}
+
+test dos 1 <<'EOF'
+2048 1023 L -
+EOF
+
+test dos 2 <<'EOF'
+2048 1023 L -
+4096 4095 L -
+EOF
+
+test dos 3 <<'EOF'
+2048 1023 L -
+4096 4095 L -
+8192 8191 L -
+EOF
+
+test dos 6 <<'EOF'
+2048 2047 L -
+4096 4095 L -
+8192 8191 L -
+16384 16383 E -
+17000 999 L -
+18000 999 L -
+EOF
+
+test gpt 1 <<'EOF'
+2048 1023 L -
+EOF
+
+test gpt 2 <<'EOF'
+2048 1023 L -
+4096 4095 L -
+EOF
+
+test gpt 3 <<'EOF'
+2048 1023 L -
+4096 4095 L -
+8192 8191 L -
+EOF
+
+test gpt 4 <<'EOF'
+2048 1023 L -
+4096 4095 L -
+8192 8191 L -
+16384 16383 L -
+EOF
+
+test gpt 5 <<'EOF'
+2048 2047 L -
+4096 4095 L -
+8192 8191 L -
+16384 16383 L -
+32768 32767 L -
+EOF
+
+test gpt 6 <<'EOF'
+2048 2047 L -
+4096 4095 L -
+8192 8191 L -
+16384 16383 L -
+32768 32767 L -
+65536 65535 L -
+EOF
-- 
2.20.1

Richard W.M. Jones

2019-Jan-20 20:59 UTC

head link

Re: [Libguestfs] [PATCH nbdkit 0/4] partition: Support MBR logical partitions.

The full series is here:
https://github.com/rwmjones/nbdkit/commits/logical-partitions

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
virt-top is 'top' for virtual machines.  Tiny program with many
powerful monitoring features, net stats, disk stats, logging, etc.
http://people.redhat.com/~rjones/virt-top

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