From 5bb2da190bc6d5a36952315dd48a00709f88c3c2 Mon Sep 17 00:00:00 2001

From: Mark McLoughlin <markmc@redhat.com>

Date: Fri, 25 Sep 2009 14:20:13 +0100

Subject: [PATCH] Re-label image file backing stores

Use virStorageFileGetMetadata() to find any backing stores for images

and re-label them

Without this, qemu cannot access qcow2 backing files, see:

  https://bugzilla.redhat.com/497131

* src/security/security_selinux.c: re-label backing store files in

  SELinuxSetSecurityImageLabel()

(cherry picked from commit fe627697a3830cd2db0efcc201d8caa9e171263d)

Includes the following commits:

  util.h needs libvirt.h for virConnectPtr

  Seems standard to include internal.h in order to pull in libvirt.h

  * src/util/util.h: include internal.h

  (cherry picked from commit 25e2857c219e7fb91412746f7919931552c4e07a)

  Move file format enum to libvirt_util

  Rename virStorageVolFormatFileSystem to virStorageFileFormat and

  move to src/util/storage_file.[ch]

  * src/Makefile.am: add src/util/storage_file.[ch]

  * src/conf/storage_conf.[ch]: move enum from here ...

  * src/util/storage_file.[ch]: .. to here

  * src/libvirt_private.syms: update To/FromString exports

  * src/storage/storage_backend.c, src/storage/storage_backend_fs.c,

    src/vbox/vbox_tmpl.c: update for above changes

  (cherry picked from commit 00fd3ff49bb1e4578756a32a812fdbf5ee335d8c)

  Split virStorageGetMetadataFromFD() from virStorageBackendProbeTarget()

  Prepare the code probing a file's format and associated metadata for

  moving into libvirt_util.

  * src/storage/storage_backend_fs.c: re-factor the format and metadata

    probing code in preparation for moving it

  (cherry picked from commit f5fc670638d94776a4eba55f5affa69f69ba1ae2)

  Introduce virStorageFileMetadata structure

  Introduce a metadata structure and make virStorageGetMetadataFromFD()

  fill it in.

  * src/util/storage_file.h: add virStorageFileMetadata

  * src/backend/storage_backend_fs.c: virStorageGetMetadataFromFD() now

    fills in the virStorageFileMetadata structure

  (cherry picked from commit 5fede0a90be565e1c44b7c8236cb8910fd06b52f)

  Move virStorageGetMetadataFromFD() to libvirt_util

  Finally, we get to the point of all this.

  Move virStorageGetMetadataFromFD() to virStorageFileGetMetadataFromFD()

  and move to src/util/storage_file.[ch]

  There's no functional changes in this patch, just code movement

  * src/storage/storage_backend_fs.c: move code from here ...

  * src/util/storage_file.[ch]: ... to here

  * src/libvirt_private.syms: export virStorageFileGetMetadataFromFD()

  (cherry picked from commit a010fb58d6bce026852d611e32302da7687639e5)

  Add virStorageFileGetMetadata() helper

  * src/util/storage_file.c: add virStorageFileGetMetadata() so that

    the caller does not need to open the file

  (cherry picked from commit 295fd6e8330c7416e2d97634364f2890133c28fa)

Fedora-patch: libvirt-svirt-relabel-qcow2-backing-files.patch

---

 src/Makefile.am          |    1 +

 src/libvirt_private.syms |    7 +-

 src/security_selinux.c   |   28 +++

 src/storage_backend.c    |   17 +-

 src/storage_backend_fs.c |  418 +++++----------------------------------------

 src/storage_conf.c       |   25 +--

 src/storage_conf.h       |   17 --

 src/storage_file.c       |  424 ++++++++++++++++++++++++++++++++++++++++++++++

 src/storage_file.h       |   62 +++++++

 src/util.h               |    1 +

 src/vbox/vbox_tmpl.c     |   15 +-

 11 files changed, 591 insertions(+), 424 deletions(-)

 create mode 100644 src/storage_file.c

 create mode 100644 src/storage_file.h

diff --git a/src/Makefile.am b/src/Makefile.am

index 463252e..3d279f2 100644

--- a/src/Makefile.am

+++ b/src/Makefile.am

@@ -54,6 +54,7 @@ UTIL_SOURCES =							\

 		hostusb.c hostusb.h				\

 		qparams.c qparams.h				\

 		storage_encryption_conf.h storage_encryption_conf.c	\

+		storage_file.c storage_file.h			\

 		threads.c threads.h				\

 		threads-pthread.h				\

 		threads-win32.h					\

diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms

index 867678f..500c209 100644

--- a/src/libvirt_private.syms

+++ b/src/libvirt_private.syms

@@ -359,8 +359,6 @@ virStorageVolDefParseNode;

 virStoragePoolFormatDiskTypeToString;

 virStoragePoolFormatFileSystemTypeToString;

 virStoragePoolFormatFileSystemNetTypeToString;

-virStorageVolFormatFileSystemTypeToString;

-virStorageVolFormatFileSystemTypeFromString;

 virStoragePoolTypeFromString;

 virStoragePartedFsTypeTypeToString;

 virStoragePoolObjLock;

@@ -373,6 +371,11 @@ virStorageEncryptionParseNode;

 virStorageEncryptionFormat;

 virStorageGenerateQcowPassphrase;

+# storage_file.h

+virStorageFileFormatTypeToString;

+virStorageFileFormatTypeFromString;

+virStorageFileGetMetadata;

+virStorageFileGetMetadataFromFD;

 # threads.h

 virMutexInit;

diff --git a/src/security_selinux.c b/src/security_selinux.c

index b4dc153..600fc75 100644

--- a/src/security_selinux.c

+++ b/src/security_selinux.c

@@ -27,6 +27,7 @@

 #include "logging.h"

 #include "pci.h"

 #include "hostusb.h"

+#include "storage_file.h"

 #define VIR_FROM_THIS VIR_FROM_SECURITY

@@ -403,10 +404,37 @@ SELinuxSetSecurityImageLabel(virConnectPtr conn,

 {

     const virSecurityLabelDefPtr secdef = &vm->def->seclabel;

+    const char *path;

     if (!disk->src)

         return 0;

+    path = disk->src;

+    do {

+        virStorageFileMetadata meta;

+        int ret;

+

+        memset(&meta, 0, sizeof(meta));

+

+        ret = virStorageFileGetMetadata(conn, path, &meta);

+

+        if (path != disk->src)

+            VIR_FREE(path);

+        path = NULL;

+

+        if (ret < 0)

+            return -1;

+

+        if (meta.backingStore != NULL &&

+            SELinuxSetFilecon(conn, meta.backingStore,

+                              default_content_context) < 0) {

+            VIR_FREE(meta.backingStore);

+            return -1;

+        }

+

+        path = meta.backingStore;

+    } while (path != NULL);

+

     if (disk->shared) {

         return SELinuxSetFilecon(conn, disk->src, default_image_context);

     } else if (disk->readonly) {

diff --git a/src/storage_backend.c b/src/storage_backend.c

index 800d4ea..1b65c5d 100644

--- a/src/storage_backend.c

+++ b/src/storage_backend.c

@@ -51,6 +51,7 @@

 #include "internal.h"

 #include "secret_conf.h"

 #include "uuid.h"

+#include "storage_file.h"

 #include "storage_backend.h"

 #include "logging.h"

@@ -462,16 +463,16 @@ virStorageBackendCreateQemuImg(virConnectPtr conn,

     char *create_tool;

     short use_kvmimg;

-    const char *type = virStorageVolFormatFileSystemTypeToString(vol->target.format);

+    const char *type = virStorageFileFormatTypeToString(vol->target.format);

     const char *backingType = vol->backingStore.path ?

-        virStorageVolFormatFileSystemTypeToString(vol->backingStore.format) : NULL;

+        virStorageFileFormatTypeToString(vol->backingStore.format) : NULL;

     const char *inputBackingPath = (inputvol ? inputvol->backingStore.path

                                              : NULL);

     const char *inputPath = inputvol ? inputvol->target.path : NULL;

     /* Treat input block devices as 'raw' format */

     const char *inputType = inputPath ?

-                            virStorageVolFormatFileSystemTypeToString(inputvol->type == VIR_STORAGE_VOL_BLOCK ? VIR_STORAGE_VOL_FILE_RAW : inputvol->target.format) :

+                            virStorageFileFormatTypeToString(inputvol->type == VIR_STORAGE_VOL_BLOCK ? VIR_STORAGE_FILE_RAW : inputvol->target.format) :

                             NULL;

     const char **imgargv;

@@ -552,8 +553,8 @@ virStorageBackendCreateQemuImg(virConnectPtr conn,

     if (vol->target.encryption != NULL) {

         virStorageEncryptionPtr enc;

-        if (vol->target.format != VIR_STORAGE_VOL_FILE_QCOW &&

-            vol->target.format != VIR_STORAGE_VOL_FILE_QCOW2) {

+        if (vol->target.format != VIR_STORAGE_FILE_QCOW &&

+            vol->target.format != VIR_STORAGE_FILE_QCOW2) {

             virStorageReportError(conn, VIR_ERR_NO_SUPPORT,

                                   _("qcow volume encryption unsupported with "

                                     "volume format %s"), type);

@@ -644,7 +645,7 @@ virStorageBackendCreateQcowCreate(virConnectPtr conn,

         return -1;

     }

-    if (vol->target.format != VIR_STORAGE_VOL_FILE_QCOW2) {

+    if (vol->target.format != VIR_STORAGE_FILE_QCOW2) {

         virStorageReportError(conn, VIR_ERR_INTERNAL_ERROR,

                               _("unsupported storage vol type %d"),

                               vol->target.format);

@@ -735,9 +736,9 @@ virStorageBackendGetBuildVolFromFunction(virConnectPtr conn,

      * tool for converting

      */

     if ((vol->type == VIR_STORAGE_VOL_FILE &&

-         vol->target.format != VIR_STORAGE_VOL_FILE_RAW) ||

+         vol->target.format != VIR_STORAGE_FILE_RAW) ||

         (inputvol->type == VIR_STORAGE_VOL_FILE &&

-         inputvol->target.format != VIR_STORAGE_VOL_FILE_RAW)) {

+         inputvol->target.format != VIR_STORAGE_FILE_RAW)) {

         if ((tool_type = virStorageBackendFindFSImageTool(NULL)) < 0) {

             virStorageReportError(conn, VIR_ERR_INTERNAL_ERROR,

diff --git a/src/storage_backend_fs.c b/src/storage_backend_fs.c

index 01cb171..6816da8 100644

--- a/src/storage_backend_fs.c

+++ b/src/storage_backend_fs.c

@@ -41,259 +41,24 @@

 #include "virterror_internal.h"

 #include "storage_backend_fs.h"

 #include "storage_conf.h"

+#include "storage_file.h"

 #include "util.h"

 #include "memory.h"

 #include "xml.h"

-enum lv_endian {

-    LV_LITTLE_ENDIAN = 1, /* 1234 */

-    LV_BIG_ENDIAN         /* 4321 */

-};

-

-enum {

-    BACKING_STORE_OK,

-    BACKING_STORE_INVALID,

-    BACKING_STORE_ERROR,

-};

-

-static int cowGetBackingStore(virConnectPtr, char **,

-                              const unsigned char *, size_t);

-static int qcowXGetBackingStore(virConnectPtr, char **,

-                                const unsigned char *, size_t);

-static int vmdk4GetBackingStore(virConnectPtr, char **,

-                                const unsigned char *, size_t);

-

-/* Either 'magic' or 'extension' *must* be provided */

-struct FileTypeInfo {

-    int type;           /* One of the constants above */

-    const char *magic;  /* Optional string of file magic

-                         * to check at head of file */

-    const char *extension; /* Optional file extension to check */

-    enum lv_endian endian; /* Endianness of file format */

-    int versionOffset;    /* Byte offset from start of file

-                           * where we find version number,

-                           * -1 to skip version test */

-    int versionNumber;    /* Version number to validate */

-    int sizeOffset;       /* Byte offset from start of file

-                           * where we find capacity info,

-                           * -1 to use st_size as capacity */

-    int sizeBytes;        /* Number of bytes for size field */

-    int sizeMultiplier;   /* A scaling factor if size is not in bytes */

-                          /* Store a COW base image path (possibly relative),

-                           * or NULL if there is no COW base image, to RES;

-                           * return BACKING_STORE_* */

-    int qcowCryptOffset;  /* Byte offset from start of file

-                           * where to find encryption mode,

-                           * -1 if encryption is not used */

-    int (*getBackingStore)(virConnectPtr conn, char **res,

-                           const unsigned char *buf, size_t buf_size);

-};

-struct FileTypeInfo const fileTypeInfo[] = {

-    /* Bochs */

-    /* XXX Untested

-    { VIR_STORAGE_VOL_FILE_BOCHS, "Bochs Virtual HD Image", NULL,

-      LV_LITTLE_ENDIAN, 64, 0x20000,

-      32+16+16+4+4+4+4+4, 8, 1, -1, NULL },*/

-    /* CLoop */

-    /* XXX Untested

-    { VIR_STORAGE_VOL_CLOOP, "#!/bin/sh\n#V2.0 Format\nmodprobe cloop file=$0 && mount -r -t iso9660 /dev/cloop $1\n", NULL,

-      LV_LITTLE_ENDIAN, -1, 0,

-      -1, 0, 0, -1, NULL }, */

-    /* Cow */

-    { VIR_STORAGE_VOL_FILE_COW, "OOOM", NULL,

-      LV_BIG_ENDIAN, 4, 2,

-      4+4+1024+4, 8, 1, -1, cowGetBackingStore },

-    /* DMG */

-    /* XXX QEMU says there's no magic for dmg, but we should check... */

-    { VIR_STORAGE_VOL_FILE_DMG, NULL, ".dmg",

-      0, -1, 0,

-      -1, 0, 0, -1, NULL },

-    /* XXX there's probably some magic for iso we can validate too... */

-    { VIR_STORAGE_VOL_FILE_ISO, NULL, ".iso",

-      0, -1, 0,

-      -1, 0, 0, -1, NULL },

-    /* Parallels */

-    /* XXX Untested

-    { VIR_STORAGE_VOL_FILE_PARALLELS, "WithoutFreeSpace", NULL,

-      LV_LITTLE_ENDIAN, 16, 2,

-      16+4+4+4+4, 4, 512, -1, NULL },

-    */

-    /* QCow */

-    { VIR_STORAGE_VOL_FILE_QCOW, "QFI", NULL,

-      LV_BIG_ENDIAN, 4, 1,

-      4+4+8+4+4, 8, 1, 4+4+8+4+4+8+1+1+2, qcowXGetBackingStore },

-    /* QCow 2 */

-    { VIR_STORAGE_VOL_FILE_QCOW2, "QFI", NULL,

-      LV_BIG_ENDIAN, 4, 2,

-      4+4+8+4+4, 8, 1, 4+4+8+4+4+8, qcowXGetBackingStore },

-    /* VMDK 3 */

-    /* XXX Untested

-    { VIR_STORAGE_VOL_FILE_VMDK, "COWD", NULL,

-      LV_LITTLE_ENDIAN, 4, 1,

-      4+4+4, 4, 512, -1, NULL },

-    */

-    /* VMDK 4 */

-    { VIR_STORAGE_VOL_FILE_VMDK, "KDMV", NULL,

-      LV_LITTLE_ENDIAN, 4, 1,

-      4+4+4, 8, 512, -1, vmdk4GetBackingStore },

-    /* Connectix / VirtualPC */

-    /* XXX Untested

-    { VIR_STORAGE_VOL_FILE_VPC, "conectix", NULL,

-      LV_BIG_ENDIAN, -1, 0,

-      -1, 0, 0, -1, NULL},

-    */

-};

-

 #define VIR_FROM_THIS VIR_FROM_STORAGE

 static int

-cowGetBackingStore(virConnectPtr conn,

-                   char **res,

-                   const unsigned char *buf,

-                   size_t buf_size)

-{

-#define COW_FILENAME_MAXLEN 1024

-    *res = NULL;

-    if (buf_size < 4+4+ COW_FILENAME_MAXLEN)

-        return BACKING_STORE_INVALID;

-    if (buf[4+4] == '\0') /* cow_header_v2.backing_file[0] */

-        return BACKING_STORE_OK;

-

-    *res = strndup ((const char*)buf + 4+4, COW_FILENAME_MAXLEN);

-    if (*res == NULL) {

-        virReportOOMError(conn);

-        return BACKING_STORE_ERROR;

-    }

-    return BACKING_STORE_OK;

-}

-

-static int

-qcowXGetBackingStore(virConnectPtr conn,

-                     char **res,

-                     const unsigned char *buf,

-                     size_t buf_size)

-{

-    unsigned long long offset;

-    unsigned long size;

-

-    *res = NULL;

-    if (buf_size < 4+4+8+4)

-        return BACKING_STORE_INVALID;

-    offset = (((unsigned long long)buf[4+4] << 56)

-              | ((unsigned long long)buf[4+4+1] << 48)

-              | ((unsigned long long)buf[4+4+2] << 40)

-              | ((unsigned long long)buf[4+4+3] << 32)

-              | ((unsigned long long)buf[4+4+4] << 24)

-              | ((unsigned long long)buf[4+4+5] << 16)

-              | ((unsigned long long)buf[4+4+6] << 8)

-              | buf[4+4+7]); /* QCowHeader.backing_file_offset */

-    if (offset > buf_size)

-        return BACKING_STORE_INVALID;

-    size = ((buf[4+4+8] << 24)

-            | (buf[4+4+8+1] << 16)

-            | (buf[4+4+8+2] << 8)

-            | buf[4+4+8+3]); /* QCowHeader.backing_file_size */

-    if (size == 0)

-        return BACKING_STORE_OK;

-    if (offset + size > buf_size || offset + size < offset)

-        return BACKING_STORE_INVALID;

-    if (size + 1 == 0)

-        return BACKING_STORE_INVALID;

-    if (VIR_ALLOC_N(*res, size + 1) < 0) {

-        virReportOOMError(conn);

-        return BACKING_STORE_ERROR;

-    }

-    memcpy(*res, buf + offset, size);

-    (*res)[size] = '\0';

-    return BACKING_STORE_OK;

-}

-

-

-static int

-vmdk4GetBackingStore(virConnectPtr conn,

-                     char **res,

-                     const unsigned char *buf,

-                     size_t buf_size)

-{

-    static const char prefix[] = "parentFileNameHint=\"";

-

-    char desc[20*512 + 1], *start, *end;

-    size_t len;

-

-    *res = NULL;

-

-    if (buf_size <= 0x200)

-        return BACKING_STORE_INVALID;

-    len = buf_size - 0x200;

-    if (len > sizeof(desc) - 1)

-        len = sizeof(desc) - 1;

-    memcpy(desc, buf + 0x200, len);

-    desc[len] = '\0';

-    start = strstr(desc, prefix);

-    if (start == NULL)

-        return BACKING_STORE_OK;

-    start += strlen(prefix);

-    end = strchr(start, '"');

-    if (end == NULL)

-        return BACKING_STORE_INVALID;

-    if (end == start)

-        return BACKING_STORE_OK;

-    *end = '\0';

-    *res = strdup(start);

-    if (*res == NULL) {

-        virReportOOMError(conn);

-        return BACKING_STORE_ERROR;

-    }

-    return BACKING_STORE_OK;

-}

-

-/**

- * Return an absolute path corresponding to PATH, which is absolute or relative

- * to the directory containing BASE_FILE, or NULL on error

- */

-static char *absolutePathFromBaseFile(const char *base_file, const char *path)

+virStorageBackendProbeTarget(virConnectPtr conn,

+                             virStorageVolTargetPtr target,

+                             char **backingStore,

+                             unsigned long long *allocation,

+                             unsigned long long *capacity,

+                             virStorageEncryptionPtr *encryption)

 {

-    size_t base_size, path_size;

-    char *res, *p;

-

-    if (*path == '/')

-        return strdup(path);

-

-    base_size = strlen(base_file) + 1;

-    path_size = strlen(path) + 1;

-    if (VIR_ALLOC_N(res, base_size - 1 + path_size) < 0)

-        return NULL;

-    memcpy(res, base_file, base_size);

-    p = strrchr(res, '/');

-    if (p != NULL)

-        p++;

-    else

-        p = res;

-    memcpy(p, path, path_size);

-    if (VIR_REALLOC_N(res, (p + path_size) - res) < 0) {

-        /* Ignore failure */

-    }

-    return res;

-}

-

-

-

-/**

- * Probe the header of a file to determine what type of disk image

- * it is, and info about its capacity if available.

- */

-static int virStorageBackendProbeTarget(virConnectPtr conn,

-                                        virStorageVolTargetPtr target,

-                                        char **backingStore,

-                                        unsigned long long *allocation,

-                                        unsigned long long *capacity,

-                                        virStorageEncryptionPtr *encryption) {

-    int fd;

-    unsigned char head[20*512]; /* vmdk4GetBackingStore needs this much. */

-    int len, i, ret;

+    int fd, ret;

+    virStorageFileMetadata meta;

-    if (backingStore)

-        *backingStore = NULL;

     if (encryption)

         *encryption = NULL;

@@ -311,148 +76,51 @@ static int virStorageBackendProbeTarget(virConnectPtr conn,

         return ret; /* Take care to propagate ret, it is not always -1 */

     }

-    if ((len = read(fd, head, sizeof(head))) < 0) {

-        virReportSystemError(conn, errno,

-                             _("cannot read header '%s'"),

-                             target->path);

+    memset(&meta, 0, sizeof(meta));

+

+    if (virStorageFileGetMetadataFromFD(conn, target->path, fd, &meta) < 0) {

         close(fd);

         return -1;

     }

     close(fd);

-    /* First check file magic */

-    for (i = 0 ; i < ARRAY_CARDINALITY(fileTypeInfo) ; i++) {

-        int mlen;

-        bool encrypted_qcow = false;

-

-        if (fileTypeInfo[i].magic == NULL)

-            continue;

-

-        /* Validate magic data */

-        mlen = strlen(fileTypeInfo[i].magic);

-        if (mlen > len)

-            continue;

-        if (memcmp(head, fileTypeInfo[i].magic, mlen) != 0)

-            continue;

-

-        /* Validate version number info */

-        if (fileTypeInfo[i].versionNumber != -1) {

-            int version;

-

-            if (fileTypeInfo[i].endian == LV_LITTLE_ENDIAN) {

-                version = (head[fileTypeInfo[i].versionOffset+3] << 24) |

-                    (head[fileTypeInfo[i].versionOffset+2] << 16) |

-                    (head[fileTypeInfo[i].versionOffset+1] << 8) |

-                    head[fileTypeInfo[i].versionOffset];

-            } else {

-                version = (head[fileTypeInfo[i].versionOffset] << 24) |

-                    (head[fileTypeInfo[i].versionOffset+1] << 16) |

-                    (head[fileTypeInfo[i].versionOffset+2] << 8) |

-                    head[fileTypeInfo[i].versionOffset+3];

-            }

-            if (version != fileTypeInfo[i].versionNumber)

-                continue;

-        }

-

-        /* Optionally extract capacity from file */

-        if (fileTypeInfo[i].sizeOffset != -1 && capacity) {

-            if (fileTypeInfo[i].endian == LV_LITTLE_ENDIAN) {

-                *capacity =

-                    ((unsigned long long)head[fileTypeInfo[i].sizeOffset+7] << 56) |

-                    ((unsigned long long)head[fileTypeInfo[i].sizeOffset+6] << 48) |

-                    ((unsigned long long)head[fileTypeInfo[i].sizeOffset+5] << 40) |

-                    ((unsigned long long)head[fileTypeInfo[i].sizeOffset+4] << 32) |

-                    ((unsigned long long)head[fileTypeInfo[i].sizeOffset+3] << 24) |

-                    ((unsigned long long)head[fileTypeInfo[i].sizeOffset+2] << 16) |

-                    ((unsigned long long)head[fileTypeInfo[i].sizeOffset+1] << 8) |

-                    ((unsigned long long)head[fileTypeInfo[i].sizeOffset]);

-            } else {

-                *capacity =

-                    ((unsigned long long)head[fileTypeInfo[i].sizeOffset] << 56) |

-                    ((unsigned long long)head[fileTypeInfo[i].sizeOffset+1] << 48) |

-                    ((unsigned long long)head[fileTypeInfo[i].sizeOffset+2] << 40) |

-                    ((unsigned long long)head[fileTypeInfo[i].sizeOffset+3] << 32) |

-                    ((unsigned long long)head[fileTypeInfo[i].sizeOffset+4] << 24) |

-                    ((unsigned long long)head[fileTypeInfo[i].sizeOffset+5] << 16) |

-                    ((unsigned long long)head[fileTypeInfo[i].sizeOffset+6] << 8) |

-                    ((unsigned long long)head[fileTypeInfo[i].sizeOffset+7]);

-            }

-            /* Avoid unlikely, but theoretically possible overflow */

-            if (*capacity > (ULLONG_MAX / fileTypeInfo[i].sizeMultiplier))

-                continue;

-            *capacity *= fileTypeInfo[i].sizeMultiplier;

-        }

-

-        if (fileTypeInfo[i].qcowCryptOffset != -1) {

-            int crypt_format;

+    target->format = meta.format;

-            crypt_format = (head[fileTypeInfo[i].qcowCryptOffset] << 24) |

-                (head[fileTypeInfo[i].qcowCryptOffset+1] << 16) |

-                (head[fileTypeInfo[i].qcowCryptOffset+2] << 8) |

-                head[fileTypeInfo[i].qcowCryptOffset+3];

-            encrypted_qcow = crypt_format != 0;

-        }

-

-        /* Validation passed, we know the file format now */

-        target->format = fileTypeInfo[i].type;

-        if (fileTypeInfo[i].getBackingStore != NULL && backingStore) {

-            char *base;

+    if (backingStore) {

+        *backingStore = meta.backingStore;

+        meta.backingStore = NULL;

+    }

-            switch (fileTypeInfo[i].getBackingStore(conn, &base, head, len)) {

-            case BACKING_STORE_OK:

-                break;

+    VIR_FREE(meta.backingStore);

-            case BACKING_STORE_INVALID:

-                continue;

+    if (capacity && meta.capacity)

+        *capacity = meta.capacity;

-            case BACKING_STORE_ERROR:

-                return -1;

-            }

-            if (base != NULL) {

-                *backingStore

-                    = absolutePathFromBaseFile(target->path, base);

-                VIR_FREE(base);

-                if (*backingStore == NULL) {

-                    virReportOOMError(conn);

-                    return -1;

-                }

-            }

+    if (encryption != NULL && meta.encrypted) {

+        if (VIR_ALLOC(*encryption) < 0) {

+            virReportOOMError(conn);

+            if (backingStore)

+                VIR_FREE(*backingStore);

+            return -1;

         }

-        if (encryption != NULL && encrypted_qcow) {

-            virStorageEncryptionPtr enc;

-            if (VIR_ALLOC(enc) < 0) {

-                virReportOOMError(conn);

-                if (backingStore)

-                    VIR_FREE(*backingStore);

-                return -1;

-            }

-            enc->format = VIR_STORAGE_ENCRYPTION_FORMAT_QCOW;

-            *encryption = enc;

-            /* XXX ideally we'd fill in secret UUID here

-             * but we cannot guarentee 'conn' is non-NULL

-             * at this point in time :-(  So we only fill

-             * in secrets when someone first queries a vol

-             */

+        switch (target->format) {

+        case VIR_STORAGE_FILE_QCOW:

+        case VIR_STORAGE_FILE_QCOW2:

+            (*encryption)->format = VIR_STORAGE_ENCRYPTION_FORMAT_QCOW;

+            break;

+        default:

+            break;

         }

-        return 0;

-    }

-

-    /* No magic, so check file extension */

-    for (i = 0 ; i < ARRAY_CARDINALITY(fileTypeInfo) ; i++) {

-        if (fileTypeInfo[i].extension == NULL)

-            continue;

-

-        if (!virFileHasSuffix(target->path, fileTypeInfo[i].extension))

-            continue;

-        target->format = fileTypeInfo[i].type;

-        return 0;

+        /* XXX ideally we'd fill in secret UUID here

+         * but we cannot guarentee 'conn' is non-NULL

+         * at this point in time :-(  So we only fill

+         * in secrets when someone first queries a vol

+         */

     }

-    /* All fails, so call it a raw file */

-    target->format = VIR_STORAGE_VOL_FILE_RAW;

     return 0;

 }

@@ -891,7 +559,7 @@ virStorageBackendFileSystemRefresh(virConnectPtr conn,

             goto no_memory;

         vol->type = VIR_STORAGE_VOL_FILE;

-        vol->target.format = VIR_STORAGE_VOL_FILE_RAW; /* Real value is filled in during probe */

+        vol->target.format = VIR_STORAGE_FILE_RAW; /* Real value is filled in during probe */

         if (virAsprintf(&vol->target.path, "%s/%s",

                         pool->def->target.path,

                         vol->name) == -1)

@@ -918,7 +586,7 @@ virStorageBackendFileSystemRefresh(virConnectPtr conn,

         }

         if (backingStore != NULL) {

-            if (vol->target.format == VIR_STORAGE_VOL_FILE_QCOW2 &&

+            if (vol->target.format == VIR_STORAGE_FILE_QCOW2 &&

                 STRPREFIX("fmt:", backingStore)) {

                 char *fmtstr = backingStore + 4;

                 char *path = strchr(fmtstr, ':');

@@ -927,7 +595,7 @@ virStorageBackendFileSystemRefresh(virConnectPtr conn,

                 } else {

                     *path = '\0';

                     if ((vol->backingStore.format =

-                         virStorageVolFormatFileSystemTypeFromString(fmtstr)) < 0) {

+                         virStorageFileFormatTypeFromString(fmtstr)) < 0) {

                         VIR_FREE(backingStore);

                     } else {

                         memmove(backingStore, path, strlen(path) + 1);

@@ -1121,9 +789,9 @@ _virStorageBackendFileSystemVolBuild(virConnectPtr conn,

                                                                inputvol);

         if (!create_func)

             return -1;

-    } else if (vol->target.format == VIR_STORAGE_VOL_FILE_RAW) {

+    } else if (vol->target.format == VIR_STORAGE_FILE_RAW) {

         create_func = virStorageBackendCreateRaw;

-    } else if (vol->target.format == VIR_STORAGE_VOL_FILE_DIR) {

+    } else if (vol->target.format == VIR_STORAGE_FILE_DIR) {

         create_func = createFileDir;

     } else if ((tool_type = virStorageBackendFindFSImageTool(NULL)) != -1) {

         create_func = virStorageBackendFSImageToolTypeToFunc(conn, tool_type);

diff --git a/src/storage_conf.c b/src/storage_conf.c

index cb063cc..788de15 100644

--- a/src/storage_conf.c

+++ b/src/storage_conf.c

@@ -36,6 +36,7 @@

 #include "virterror_internal.h"

 #include "datatypes.h"

 #include "storage_conf.h"

+#include "storage_file.h"

 #include "xml.h"

 #include "uuid.h"

@@ -82,12 +83,6 @@ VIR_ENUM_IMPL(virStorageVolFormatDisk,

               "linux-lvm", "linux-raid",

               "extended")

-VIR_ENUM_IMPL(virStorageVolFormatFileSystem,

-              VIR_STORAGE_VOL_FILE_LAST,

-              "raw", "dir", "bochs",

-              "cloop", "cow", "dmg", "iso",

-              "qcow", "qcow2", "vmdk", "vpc")

-

 VIR_ENUM_IMPL(virStoragePartedFsType,

               VIR_STORAGE_PARTED_FS_TYPE_LAST,

               "ext2", "ext2", "fat16",

@@ -150,9 +145,9 @@ static virStoragePoolTypeInfo poolTypeInfo[] = {

     },

     { .poolType = VIR_STORAGE_POOL_DIR,

       .volOptions = {

-            .defaultFormat = VIR_STORAGE_VOL_FILE_RAW,

-            .formatFromString = virStorageVolFormatFileSystemTypeFromString,

-            .formatToString = virStorageVolFormatFileSystemTypeToString,

+            .defaultFormat = VIR_STORAGE_FILE_RAW,

+            .formatFromString = virStorageFileFormatTypeFromString,

+            .formatToString = virStorageFileFormatTypeToString,

         },

     },

     { .poolType = VIR_STORAGE_POOL_FS,

@@ -162,9 +157,9 @@ static virStoragePoolTypeInfo poolTypeInfo[] = {

             .formatToString = virStoragePoolFormatFileSystemTypeToString,

         },

       .volOptions = {

-            .defaultFormat = VIR_STORAGE_VOL_FILE_RAW,

-            .formatFromString = virStorageVolFormatFileSystemTypeFromString,

-            .formatToString = virStorageVolFormatFileSystemTypeToString,

+            .defaultFormat = VIR_STORAGE_FILE_RAW,

+            .formatFromString = virStorageFileFormatTypeFromString,

+            .formatToString = virStorageFileFormatTypeToString,

         },

     },

     { .poolType = VIR_STORAGE_POOL_NETFS,

@@ -176,9 +171,9 @@ static virStoragePoolTypeInfo poolTypeInfo[] = {

             .formatToString = virStoragePoolFormatFileSystemNetTypeToString,

         },

       .volOptions = {

-            .defaultFormat = VIR_STORAGE_VOL_FILE_RAW,

-            .formatFromString = virStorageVolFormatFileSystemTypeFromString,

-            .formatToString = virStorageVolFormatFileSystemTypeToString,

+            .defaultFormat = VIR_STORAGE_FILE_RAW,

+            .formatFromString = virStorageFileFormatTypeFromString,

+            .formatToString = virStorageFileFormatTypeToString,

         },

     },

     { .poolType = VIR_STORAGE_POOL_ISCSI,

diff --git a/src/storage_conf.h b/src/storage_conf.h

index 421d305..9fedb12 100644

--- a/src/storage_conf.h

+++ b/src/storage_conf.h

@@ -429,23 +429,6 @@ enum virStoragePoolFormatLogical {

 };

 VIR_ENUM_DECL(virStoragePoolFormatLogical)

-

-enum virStorageVolFormatFileSystem {

-    VIR_STORAGE_VOL_FILE_RAW = 0,

-    VIR_STORAGE_VOL_FILE_DIR,

-    VIR_STORAGE_VOL_FILE_BOCHS,

-    VIR_STORAGE_VOL_FILE_CLOOP,

-    VIR_STORAGE_VOL_FILE_COW,

-    VIR_STORAGE_VOL_FILE_DMG,

-    VIR_STORAGE_VOL_FILE_ISO,

-    VIR_STORAGE_VOL_FILE_QCOW,

-    VIR_STORAGE_VOL_FILE_QCOW2,

-    VIR_STORAGE_VOL_FILE_VMDK,

-    VIR_STORAGE_VOL_FILE_VPC,

-    VIR_STORAGE_VOL_FILE_LAST,

-};

-VIR_ENUM_DECL(virStorageVolFormatFileSystem)

-

 /*

  * XXX these are basically partition types.

  *

diff --git a/src/storage_file.c b/src/storage_file.c

new file mode 100644

index 0000000..44057d2

--- /dev/null

+++ b/src/storage_file.c

@@ -0,0 +1,424 @@

+/*

+ * storage_file.c: file utility functions for FS storage backend

+ *

+ * Copyright (C) 2007-2009 Red Hat, Inc.

+ * Copyright (C) 2007-2008 Daniel P. Berrange

+ *

+ * This library is free software; you can redistribute it and/or

+ * modify it under the terms of the GNU Lesser General Public

+ * License as published by the Free Software Foundation; either

+ * version 2.1 of the License, or (at your option) any later version.

+ *

+ * This library 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

+ * Lesser General Public License for more details.

+ *

+ * You should have received a copy of the GNU Lesser General Public

+ * License along with this library; if not, write to the Free Software

+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307  USA

+ *

+ * Author: Daniel P. Berrange <berrange@redhat.com>

+ */

+

+#include <config.h>

+#include "storage_file.h"

+

+#include <unistd.h>

+#include <fcntl.h>

+#include "memory.h"

+#include "virterror_internal.h"

+

+#define VIR_FROM_THIS VIR_FROM_STORAGE