linux-brain/include/linux/ceph/msgr.h
Ilya Dryomov 6daca13d2e libceph: add authorizer challenge
When a client authenticates with a service, an authorizer is sent with
a nonce to the service (ceph_x_authorize_[ab]) and the service responds
with a mutation of that nonce (ceph_x_authorize_reply).  This lets the
client verify the service is who it says it is but it doesn't protect
against a replay: someone can trivially capture the exchange and reuse
the same authorizer to authenticate themselves.

Allow the service to reject an initial authorizer with a random
challenge (ceph_x_authorize_challenge).  The client then has to respond
with an updated authorizer proving they are able to decrypt the
service's challenge and that the new authorizer was produced for this
specific connection instance.

The accepting side requires this challenge and response unconditionally
if the client side advertises they have CEPHX_V2 feature bit.

This addresses CVE-2018-1128.

Link: http://tracker.ceph.com/issues/24836
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Sage Weil <sage@redhat.com>
2018-08-02 21:33:24 +02:00

189 lines
5.6 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef CEPH_MSGR_H
#define CEPH_MSGR_H
/*
* Data types for message passing layer used by Ceph.
*/
#define CEPH_MON_PORT 6789 /* default monitor port */
/*
* client-side processes will try to bind to ports in this
* range, simply for the benefit of tools like nmap or wireshark
* that would like to identify the protocol.
*/
#define CEPH_PORT_FIRST 6789
#define CEPH_PORT_START 6800 /* non-monitors start here */
#define CEPH_PORT_LAST 6900
/*
* tcp connection banner. include a protocol version. and adjust
* whenever the wire protocol changes. try to keep this string length
* constant.
*/
#define CEPH_BANNER "ceph v027"
#define CEPH_BANNER_MAX_LEN 30
/*
* Rollover-safe type and comparator for 32-bit sequence numbers.
* Comparator returns -1, 0, or 1.
*/
typedef __u32 ceph_seq_t;
static inline __s32 ceph_seq_cmp(__u32 a, __u32 b)
{
return (__s32)a - (__s32)b;
}
/*
* entity_name -- logical name for a process participating in the
* network, e.g. 'mds0' or 'osd3'.
*/
struct ceph_entity_name {
__u8 type; /* CEPH_ENTITY_TYPE_* */
__le64 num;
} __attribute__ ((packed));
#define CEPH_ENTITY_TYPE_MON 0x01
#define CEPH_ENTITY_TYPE_MDS 0x02
#define CEPH_ENTITY_TYPE_OSD 0x04
#define CEPH_ENTITY_TYPE_CLIENT 0x08
#define CEPH_ENTITY_TYPE_AUTH 0x20
#define CEPH_ENTITY_TYPE_ANY 0xFF
extern const char *ceph_entity_type_name(int type);
/*
* entity_addr -- network address
*/
struct ceph_entity_addr {
__le32 type;
__le32 nonce; /* unique id for process (e.g. pid) */
struct sockaddr_storage in_addr;
} __attribute__ ((packed));
struct ceph_entity_inst {
struct ceph_entity_name name;
struct ceph_entity_addr addr;
} __attribute__ ((packed));
/* used by message exchange protocol */
#define CEPH_MSGR_TAG_READY 1 /* server->client: ready for messages */
#define CEPH_MSGR_TAG_RESETSESSION 2 /* server->client: reset, try again */
#define CEPH_MSGR_TAG_WAIT 3 /* server->client: wait for racing
incoming connection */
#define CEPH_MSGR_TAG_RETRY_SESSION 4 /* server->client + cseq: try again
with higher cseq */
#define CEPH_MSGR_TAG_RETRY_GLOBAL 5 /* server->client + gseq: try again
with higher gseq */
#define CEPH_MSGR_TAG_CLOSE 6 /* closing pipe */
#define CEPH_MSGR_TAG_MSG 7 /* message */
#define CEPH_MSGR_TAG_ACK 8 /* message ack */
#define CEPH_MSGR_TAG_KEEPALIVE 9 /* just a keepalive byte! */
#define CEPH_MSGR_TAG_BADPROTOVER 10 /* bad protocol version */
#define CEPH_MSGR_TAG_BADAUTHORIZER 11 /* bad authorizer */
#define CEPH_MSGR_TAG_FEATURES 12 /* insufficient features */
#define CEPH_MSGR_TAG_SEQ 13 /* 64-bit int follows with seen seq number */
#define CEPH_MSGR_TAG_KEEPALIVE2 14 /* keepalive2 byte + ceph_timespec */
#define CEPH_MSGR_TAG_KEEPALIVE2_ACK 15 /* keepalive2 reply */
#define CEPH_MSGR_TAG_CHALLENGE_AUTHORIZER 16 /* cephx v2 doing server challenge */
/*
* connection negotiation
*/
struct ceph_msg_connect {
__le64 features; /* supported feature bits */
__le32 host_type; /* CEPH_ENTITY_TYPE_* */
__le32 global_seq; /* count connections initiated by this host */
__le32 connect_seq; /* count connections initiated in this session */
__le32 protocol_version;
__le32 authorizer_protocol;
__le32 authorizer_len;
__u8 flags; /* CEPH_MSG_CONNECT_* */
} __attribute__ ((packed));
struct ceph_msg_connect_reply {
__u8 tag;
__le64 features; /* feature bits for this session */
__le32 global_seq;
__le32 connect_seq;
__le32 protocol_version;
__le32 authorizer_len;
__u8 flags;
} __attribute__ ((packed));
#define CEPH_MSG_CONNECT_LOSSY 1 /* messages i send may be safely dropped */
/*
* message header
*/
struct ceph_msg_header_old {
__le64 seq; /* message seq# for this session */
__le64 tid; /* transaction id */
__le16 type; /* message type */
__le16 priority; /* priority. higher value == higher priority */
__le16 version; /* version of message encoding */
__le32 front_len; /* bytes in main payload */
__le32 middle_len;/* bytes in middle payload */
__le32 data_len; /* bytes of data payload */
__le16 data_off; /* sender: include full offset;
receiver: mask against ~PAGE_MASK */
struct ceph_entity_inst src, orig_src;
__le32 reserved;
__le32 crc; /* header crc32c */
} __attribute__ ((packed));
struct ceph_msg_header {
__le64 seq; /* message seq# for this session */
__le64 tid; /* transaction id */
__le16 type; /* message type */
__le16 priority; /* priority. higher value == higher priority */
__le16 version; /* version of message encoding */
__le32 front_len; /* bytes in main payload */
__le32 middle_len;/* bytes in middle payload */
__le32 data_len; /* bytes of data payload */
__le16 data_off; /* sender: include full offset;
receiver: mask against ~PAGE_MASK */
struct ceph_entity_name src;
__le16 compat_version;
__le16 reserved;
__le32 crc; /* header crc32c */
} __attribute__ ((packed));
#define CEPH_MSG_PRIO_LOW 64
#define CEPH_MSG_PRIO_DEFAULT 127
#define CEPH_MSG_PRIO_HIGH 196
#define CEPH_MSG_PRIO_HIGHEST 255
/*
* follows data payload
*/
struct ceph_msg_footer_old {
__le32 front_crc, middle_crc, data_crc;
__u8 flags;
} __attribute__ ((packed));
struct ceph_msg_footer {
__le32 front_crc, middle_crc, data_crc;
// sig holds the 64 bits of the digital signature for the message PLR
__le64 sig;
__u8 flags;
} __attribute__ ((packed));
#define CEPH_MSG_FOOTER_COMPLETE (1<<0) /* msg wasn't aborted */
#define CEPH_MSG_FOOTER_NOCRC (1<<1) /* no data crc */
#define CEPH_MSG_FOOTER_SIGNED (1<<2) /* msg was signed */
#endif