crypto: add support for generating initialization vectors

There are a number of different algorithms that can be used
to generate initialization vectors for disk encryption. This
introduces a simple internal QCryptoBlockIV object to provide
a consistent internal API to the different algorithms. The
initially implemented algorithms are 'plain', 'plain64' and
'essiv', each matching the same named algorithm provided
by the Linux kernel dm-crypt driver.

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>

1 files changed, 19 insertions, 0 deletions

diff --git a/qapi/crypto.json b/qapi/crypto.json
index 4bd690fcfb..42b979a0d5 100644
--- a/qapi/crypto.json
+++ b/qapi/crypto.json
@@ -78,3 +78,22 @@
 { 'enum': 'QCryptoCipherMode',
   'prefix': 'QCRYPTO_CIPHER_MODE',
   'data': ['ecb', 'cbc']}
+
+
+##
+# QCryptoIVGenAlgorithm:
+#
+# The supported algorithms for generating initialization
+# vectors for full disk encryption. The 'plain' generator
+# should not be used for disks with sector numbers larger
+# than 2^32, except where compatibility with pre-existing
+# Linux dm-crypt volumes is required.
+#
+# @plain: 64-bit sector number truncated to 32-bits
+# @plain64: 64-bit sector number
+# @essiv: 64-bit sector number encrypted with a hash of the encryption key
+# Since: 2.6
+##
+{ 'enum': 'QCryptoIVGenAlgorithm',
+  'prefix': 'QCRYPTO_IVGEN_ALG',
+  'data': ['plain', 'plain64', 'essiv']}