[Qemu-devel] [PATCH RFC 1/2] block: Limit opening of encrypted images to qemu-img

[Markus Armbruster <armbru@redhat.com>]

Signed-off-by: Markus Armbruster <armbru@redhat.com>
---
 block/qcow.c          | 5 +++++
 block/qcow2.c         | 5 +++++
 include/block/block.h | 3 +--
 qemu-img.c            | 1 +
 4 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/block/qcow.c b/block/qcow.c
index 0558969..f54fc86 100644
--- a/block/qcow.c
+++ b/block/qcow.c
@@ -155,6 +155,11 @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags,
     }
     s->crypt_method_header = header.crypt_method;
     if (s->crypt_method_header) {
+        if (!(flags & BDRV_O_CRYPT_OK)) {
+            error_setg(errp, "image is encrypted, use qemu-img to decrypt it");
+            ret = -EINVAL;
+            goto fail;
+        }
         bs->encrypted = 1;
     }
     s->cluster_bits = header.cluster_bits;
diff --git a/block/qcow2.c b/block/qcow2.c
index 50e0a94..b12c67a 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -693,6 +693,11 @@ static int qcow2_open(BlockDriverState *bs, QDict *options, int flags,
     }
     s->crypt_method_header = header.crypt_method;
     if (s->crypt_method_header) {
+        if (!(flags & BDRV_O_CRYPT_OK)) {
+            error_setg(errp, "image is encrypted, use qemu-img to decrypt it");
+            ret = -EINVAL;
+            goto fail;
+        }
         bs->encrypted = 1;
     }
 
diff --git a/include/block/block.h b/include/block/block.h
index 649c269..76b6d3c 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -76,6 +76,7 @@ typedef enum {
 #define BDRV_O_PROTOCOL    0x8000  /* if no block driver is explicitly given:
                                       select an appropriate protocol driver,
                                       ignoring the format layer */
+#define BDRV_O_CRYPT_OK    0x10000 /* open even when image is encrypted */
 
 #define BDRV_O_CACHE_MASK  (BDRV_O_NOCACHE | BDRV_O_CACHE_WB | BDRV_O_NO_FLUSH)
 
@@ -382,8 +383,6 @@ BlockDriverState *bdrv_next(BlockDriverState *bs);
 int bdrv_is_encrypted(BlockDriverState *bs);
 int bdrv_key_required(BlockDriverState *bs);
 int bdrv_set_key(BlockDriverState *bs, const char *key);
-void bdrv_add_key(BlockDriverState *bs, const char *key, Error **errp);
-int bdrv_query_missing_keys(void);
 void bdrv_iterate_format(void (*it)(void *opaque, const char *name),
                          void *opaque);
 const char *bdrv_get_node_name(const BlockDriverState *bs);
diff --git a/qemu-img.c b/qemu-img.c
index 7ac7f56..bcd7d3f 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -302,6 +302,7 @@ static BlockBackend *img_open(const char *id, const char *filename,
         qdict_put(options, "driver", qstring_from_str(fmt));
     }
 
+    flags |= BDRV_O_CRYPT_OK;
     blk = blk_new_open(id, filename, NULL, options, flags, &local_err);
     if (!blk) {
         error_report("Could not open '%s': %s", filename,
-- 
1.9.3