libceph: implement CEPHX_V2 calculation mode

commit cc255c76c70f7a87d97939621eae04b600d9f4a1 upstream.

Derive the signature from the entire buffer (both AES cipher blocks)
instead of using just the first half of the first block, leaving out
data_crc entirely.

This addresses CVE-2018-1129.

Link: http://tracker.ceph.com/issues/24837
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Sage Weil <sage@redhat.com>
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Ilya Dryomov 2018-07-27 19:25:32 +02:00 committed by Greg Kroah-Hartman
parent 3fd73c8a71
commit b16d0c5d32
2 changed files with 60 additions and 20 deletions

View File

@ -165,9 +165,9 @@ DEFINE_CEPH_FEATURE(58, 1, FS_FILE_LAYOUT_V2) // overlap
DEFINE_CEPH_FEATURE(59, 1, FS_BTIME)
DEFINE_CEPH_FEATURE(59, 1, FS_CHANGE_ATTR) // overlap
DEFINE_CEPH_FEATURE(59, 1, MSG_ADDR2) // overlap
DEFINE_CEPH_FEATURE(60, 1, BLKIN_TRACING) // *do not share this bit*
DEFINE_CEPH_FEATURE(60, 1, OSD_RECOVERY_DELETES) // *do not share this bit*
DEFINE_CEPH_FEATURE(61, 1, CEPHX_V2) // *do not share this bit*
DEFINE_CEPH_FEATURE(61, 1, RESERVED2) // unused, but slow down!
DEFINE_CEPH_FEATURE(62, 1, RESERVED) // do not use; used as a sentinal
DEFINE_CEPH_FEATURE_DEPRECATED(63, 1, RESERVED_BROKEN, LUMINOUS) // client-facing
@ -209,7 +209,8 @@ DEFINE_CEPH_FEATURE_DEPRECATED(63, 1, RESERVED_BROKEN, LUMINOUS) // client-facin
CEPH_FEATURE_SERVER_JEWEL | \
CEPH_FEATURE_MON_STATEFUL_SUB | \
CEPH_FEATURE_CRUSH_TUNABLES5 | \
CEPH_FEATURE_NEW_OSDOPREPLY_ENCODING)
CEPH_FEATURE_NEW_OSDOPREPLY_ENCODING | \
CEPH_FEATURE_CEPHX_V2)
#define CEPH_FEATURES_REQUIRED_DEFAULT \
(CEPH_FEATURE_NOSRCADDR | \

View File

@ -9,6 +9,7 @@
#include <linux/ceph/decode.h>
#include <linux/ceph/auth.h>
#include <linux/ceph/ceph_features.h>
#include <linux/ceph/libceph.h>
#include <linux/ceph/messenger.h>
@ -803,26 +804,64 @@ static int calc_signature(struct ceph_x_authorizer *au, struct ceph_msg *msg,
__le64 *psig)
{
void *enc_buf = au->enc_buf;
struct {
__le32 len;
__le32 header_crc;
__le32 front_crc;
__le32 middle_crc;
__le32 data_crc;
} __packed *sigblock = enc_buf + ceph_x_encrypt_offset();
int ret;
sigblock->len = cpu_to_le32(4*sizeof(u32));
sigblock->header_crc = msg->hdr.crc;
sigblock->front_crc = msg->footer.front_crc;
sigblock->middle_crc = msg->footer.middle_crc;
sigblock->data_crc = msg->footer.data_crc;
ret = ceph_x_encrypt(&au->session_key, enc_buf, CEPHX_AU_ENC_BUF_LEN,
sizeof(*sigblock));
if (ret < 0)
return ret;
if (!CEPH_HAVE_FEATURE(msg->con->peer_features, CEPHX_V2)) {
struct {
__le32 len;
__le32 header_crc;
__le32 front_crc;
__le32 middle_crc;
__le32 data_crc;
} __packed *sigblock = enc_buf + ceph_x_encrypt_offset();
sigblock->len = cpu_to_le32(4*sizeof(u32));
sigblock->header_crc = msg->hdr.crc;
sigblock->front_crc = msg->footer.front_crc;
sigblock->middle_crc = msg->footer.middle_crc;
sigblock->data_crc = msg->footer.data_crc;
ret = ceph_x_encrypt(&au->session_key, enc_buf,
CEPHX_AU_ENC_BUF_LEN, sizeof(*sigblock));
if (ret < 0)
return ret;
*psig = *(__le64 *)(enc_buf + sizeof(u32));
} else {
struct {
__le32 header_crc;
__le32 front_crc;
__le32 front_len;
__le32 middle_crc;
__le32 middle_len;
__le32 data_crc;
__le32 data_len;
__le32 seq_lower_word;
} __packed *sigblock = enc_buf;
struct {
__le64 a, b, c, d;
} __packed *penc = enc_buf;
int ciphertext_len;
sigblock->header_crc = msg->hdr.crc;
sigblock->front_crc = msg->footer.front_crc;
sigblock->front_len = msg->hdr.front_len;
sigblock->middle_crc = msg->footer.middle_crc;
sigblock->middle_len = msg->hdr.middle_len;
sigblock->data_crc = msg->footer.data_crc;
sigblock->data_len = msg->hdr.data_len;
sigblock->seq_lower_word = *(__le32 *)&msg->hdr.seq;
/* no leading len, no ceph_x_encrypt_header */
ret = ceph_crypt(&au->session_key, true, enc_buf,
CEPHX_AU_ENC_BUF_LEN, sizeof(*sigblock),
&ciphertext_len);
if (ret)
return ret;
*psig = penc->a ^ penc->b ^ penc->c ^ penc->d;
}
*psig = *(__le64 *)(enc_buf + sizeof(u32));
return 0;
}