xref: /openbmc/linux/net/rxrpc/protocol.h (revision 160b8e75)
1 /* packet.h: Rx packet layout and definitions
2  *
3  * Copyright (C) 2002, 2007 Red Hat, Inc. All Rights Reserved.
4  * Written by David Howells (dhowells@redhat.com)
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License
8  * as published by the Free Software Foundation; either version
9  * 2 of the License, or (at your option) any later version.
10  */
11 
12 #ifndef _LINUX_RXRPC_PACKET_H
13 #define _LINUX_RXRPC_PACKET_H
14 
15 typedef u32	rxrpc_seq_t;	/* Rx message sequence number */
16 typedef u32	rxrpc_serial_t;	/* Rx message serial number */
17 typedef __be32	rxrpc_seq_net_t; /* on-the-wire Rx message sequence number */
18 typedef __be32	rxrpc_serial_net_t; /* on-the-wire Rx message serial number */
19 
20 /*****************************************************************************/
21 /*
22  * on-the-wire Rx packet header
23  * - all multibyte fields should be in network byte order
24  */
25 struct rxrpc_wire_header {
26 	__be32		epoch;		/* client boot timestamp */
27 #define RXRPC_RANDOM_EPOCH	0x80000000	/* Random if set, date-based if not */
28 
29 	__be32		cid;		/* connection and channel ID */
30 #define RXRPC_MAXCALLS		4			/* max active calls per conn */
31 #define RXRPC_CHANNELMASK	(RXRPC_MAXCALLS-1)	/* mask for channel ID */
32 #define RXRPC_CIDMASK		(~RXRPC_CHANNELMASK)	/* mask for connection ID */
33 #define RXRPC_CIDSHIFT		ilog2(RXRPC_MAXCALLS)	/* shift for connection ID */
34 #define RXRPC_CID_INC		(1 << RXRPC_CIDSHIFT)	/* connection ID increment */
35 
36 	__be32		callNumber;	/* call ID (0 for connection-level packets) */
37 	__be32		seq;		/* sequence number of pkt in call stream */
38 	__be32		serial;		/* serial number of pkt sent to network */
39 
40 	uint8_t		type;		/* packet type */
41 #define RXRPC_PACKET_TYPE_DATA		1	/* data */
42 #define RXRPC_PACKET_TYPE_ACK		2	/* ACK */
43 #define RXRPC_PACKET_TYPE_BUSY		3	/* call reject */
44 #define RXRPC_PACKET_TYPE_ABORT		4	/* call/connection abort */
45 #define RXRPC_PACKET_TYPE_ACKALL	5	/* ACK all outstanding packets on call */
46 #define RXRPC_PACKET_TYPE_CHALLENGE	6	/* connection security challenge (SRVR->CLNT) */
47 #define RXRPC_PACKET_TYPE_RESPONSE	7	/* connection secutity response (CLNT->SRVR) */
48 #define RXRPC_PACKET_TYPE_DEBUG		8	/* debug info request */
49 #define RXRPC_PACKET_TYPE_VERSION	13	/* version string request */
50 #define RXRPC_N_PACKET_TYPES		14	/* number of packet types (incl type 0) */
51 
52 	uint8_t		flags;		/* packet flags */
53 #define RXRPC_CLIENT_INITIATED	0x01		/* signifies a packet generated by a client */
54 #define RXRPC_REQUEST_ACK	0x02		/* request an unconditional ACK of this packet */
55 #define RXRPC_LAST_PACKET	0x04		/* the last packet from this side for this call */
56 #define RXRPC_MORE_PACKETS	0x08		/* more packets to come */
57 #define RXRPC_JUMBO_PACKET	0x20		/* [DATA] this is a jumbo packet */
58 #define RXRPC_SLOW_START_OK	0x20		/* [ACK] slow start supported */
59 
60 	uint8_t		userStatus;	/* app-layer defined status */
61 #define RXRPC_USERSTATUS_SERVICE_UPGRADE 0x01	/* AuriStor service upgrade request */
62 
63 	uint8_t		securityIndex;	/* security protocol ID */
64 	union {
65 		__be16	_rsvd;		/* reserved */
66 		__be16	cksum;		/* kerberos security checksum */
67 	};
68 	__be16		serviceId;	/* service ID */
69 
70 } __packed;
71 
72 #define RXRPC_SUPPORTED_PACKET_TYPES (			\
73 		(1 << RXRPC_PACKET_TYPE_DATA) |		\
74 		(1 << RXRPC_PACKET_TYPE_ACK) |		\
75 		(1 << RXRPC_PACKET_TYPE_BUSY) |		\
76 		(1 << RXRPC_PACKET_TYPE_ABORT) |	\
77 		(1 << RXRPC_PACKET_TYPE_ACKALL) |	\
78 		(1 << RXRPC_PACKET_TYPE_CHALLENGE) |	\
79 		(1 << RXRPC_PACKET_TYPE_RESPONSE) |	\
80 		/*(1 << RXRPC_PACKET_TYPE_DEBUG) | */	\
81 		(1 << RXRPC_PACKET_TYPE_VERSION))
82 
83 /*****************************************************************************/
84 /*
85  * jumbo packet secondary header
86  * - can be mapped to read header by:
87  *   - new_serial = serial + 1
88  *   - new_seq = seq + 1
89  *   - new_flags = j_flags
90  *   - new__rsvd = j__rsvd
91  *   - duplicating all other fields
92  */
93 struct rxrpc_jumbo_header {
94 	uint8_t		flags;		/* packet flags (as per rxrpc_header) */
95 	uint8_t		pad;
96 	union {
97 		__be16	_rsvd;		/* reserved */
98 		__be16	cksum;		/* kerberos security checksum */
99 	};
100 };
101 
102 #define RXRPC_JUMBO_DATALEN	1412	/* non-terminal jumbo packet data length */
103 #define RXRPC_JUMBO_SUBPKTLEN	(RXRPC_JUMBO_DATALEN + sizeof(struct rxrpc_jumbo_header))
104 
105 /*****************************************************************************/
106 /*
107  * on-the-wire Rx ACK packet data payload
108  * - all multibyte fields should be in network byte order
109  */
110 struct rxrpc_ackpacket {
111 	__be16		bufferSpace;	/* number of packet buffers available */
112 	__be16		maxSkew;	/* diff between serno being ACK'd and highest serial no
113 					 * received */
114 	__be32		firstPacket;	/* sequence no of first ACK'd packet in attached list */
115 	__be32		previousPacket;	/* sequence no of previous packet received */
116 	__be32		serial;		/* serial no of packet that prompted this ACK */
117 
118 	uint8_t		reason;		/* reason for ACK */
119 #define RXRPC_ACK_REQUESTED		1	/* ACK was requested on packet */
120 #define RXRPC_ACK_DUPLICATE		2	/* duplicate packet received */
121 #define RXRPC_ACK_OUT_OF_SEQUENCE	3	/* out of sequence packet received */
122 #define RXRPC_ACK_EXCEEDS_WINDOW	4	/* packet received beyond end of ACK window */
123 #define RXRPC_ACK_NOSPACE		5	/* packet discarded due to lack of buffer space */
124 #define RXRPC_ACK_PING			6	/* keep alive ACK */
125 #define RXRPC_ACK_PING_RESPONSE		7	/* response to RXRPC_ACK_PING */
126 #define RXRPC_ACK_DELAY			8	/* nothing happened since received packet */
127 #define RXRPC_ACK_IDLE			9	/* ACK due to fully received ACK window */
128 #define RXRPC_ACK__INVALID		10	/* Representation of invalid ACK reason */
129 
130 	uint8_t		nAcks;		/* number of ACKs */
131 #define RXRPC_MAXACKS	255
132 
133 	uint8_t		acks[0];	/* list of ACK/NAKs */
134 #define RXRPC_ACK_TYPE_NACK		0
135 #define RXRPC_ACK_TYPE_ACK		1
136 
137 } __packed;
138 
139 /* Some ACKs refer to specific packets and some are general and can be updated. */
140 #define RXRPC_ACK_UPDATEABLE ((1 << RXRPC_ACK_REQUESTED)	|	\
141 			      (1 << RXRPC_ACK_PING_RESPONSE)	|	\
142 			      (1 << RXRPC_ACK_DELAY)		|	\
143 			      (1 << RXRPC_ACK_IDLE))
144 
145 
146 /*
147  * ACK packets can have a further piece of information tagged on the end
148  */
149 struct rxrpc_ackinfo {
150 	__be32		rxMTU;		/* maximum Rx MTU size (bytes) [AFS 3.3] */
151 	__be32		maxMTU;		/* maximum interface MTU size (bytes) [AFS 3.3] */
152 	__be32		rwind;		/* Rx window size (packets) [AFS 3.4] */
153 	__be32		jumbo_max;	/* max packets to stick into a jumbo packet [AFS 3.5] */
154 };
155 
156 /*****************************************************************************/
157 /*
158  * Kerberos security type-2 challenge packet
159  */
160 struct rxkad_challenge {
161 	__be32		version;	/* version of this challenge type */
162 	__be32		nonce;		/* encrypted random number */
163 	__be32		min_level;	/* minimum security level */
164 	__be32		__padding;	/* padding to 8-byte boundary */
165 } __packed;
166 
167 /*****************************************************************************/
168 /*
169  * Kerberos security type-2 response packet
170  */
171 struct rxkad_response {
172 	__be32		version;	/* version of this response type */
173 	__be32		__pad;
174 
175 	/* encrypted bit of the response */
176 	struct {
177 		__be32		epoch;		/* current epoch */
178 		__be32		cid;		/* parent connection ID */
179 		__be32		checksum;	/* checksum */
180 		__be32		securityIndex;	/* security type */
181 		__be32		call_id[4];	/* encrypted call IDs */
182 		__be32		inc_nonce;	/* challenge nonce + 1 */
183 		__be32		level;		/* desired level */
184 	} encrypted;
185 
186 	__be32		kvno;		/* Kerberos key version number */
187 	__be32		ticket_len;	/* Kerberos ticket length  */
188 } __packed;
189 
190 #endif /* _LINUX_RXRPC_PACKET_H */
191