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_header {
26 	__be32		epoch;		/* client boot timestamp */
27 
28 	__be32		cid;		/* connection and channel ID */
29 #define RXRPC_MAXCALLS		4			/* max active calls per conn */
30 #define RXRPC_CHANNELMASK	(RXRPC_MAXCALLS-1)	/* mask for channel ID */
31 #define RXRPC_CIDMASK		(~RXRPC_CHANNELMASK)	/* mask for connection ID */
32 #define RXRPC_CIDSHIFT		ilog2(RXRPC_MAXCALLS)	/* shift for connection ID */
33 #define RXRPC_CID_INC		(1 << RXRPC_CIDSHIFT)	/* connection ID increment */
34 
35 	__be32		callNumber;	/* call ID (0 for connection-level packets) */
36 #define RXRPC_PROCESS_MAXCALLS	(1<<2)	/* maximum number of active calls per conn (power of 2) */
37 
38 	__be32		seq;		/* sequence number of pkt in call stream */
39 	__be32		serial;		/* serial number of pkt sent to network */
40 
41 	uint8_t		type;		/* packet type */
42 #define RXRPC_PACKET_TYPE_DATA		1	/* data */
43 #define RXRPC_PACKET_TYPE_ACK		2	/* ACK */
44 #define RXRPC_PACKET_TYPE_BUSY		3	/* call reject */
45 #define RXRPC_PACKET_TYPE_ABORT		4	/* call/connection abort */
46 #define RXRPC_PACKET_TYPE_ACKALL	5	/* ACK all outstanding packets on call */
47 #define RXRPC_PACKET_TYPE_CHALLENGE	6	/* connection security challenge (SRVR->CLNT) */
48 #define RXRPC_PACKET_TYPE_RESPONSE	7	/* connection secutity response (CLNT->SRVR) */
49 #define RXRPC_PACKET_TYPE_DEBUG		8	/* debug info request */
50 #define RXRPC_N_PACKET_TYPES		9	/* 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 	uint8_t		securityIndex;	/* security protocol ID */
62 	union {
63 		__be16	_rsvd;		/* reserved */
64 		__be16	cksum;		/* kerberos security checksum */
65 	};
66 	__be16		serviceId;	/* service ID */
67 
68 } __packed;
69 
70 #define __rxrpc_header_off(X) offsetof(struct rxrpc_header,X)
71 
72 extern const char *rxrpc_pkts[];
73 
74 /*****************************************************************************/
75 /*
76  * jumbo packet secondary header
77  * - can be mapped to read header by:
78  *   - new_serial = serial + 1
79  *   - new_seq = seq + 1
80  *   - new_flags = j_flags
81  *   - new__rsvd = j__rsvd
82  *   - duplicating all other fields
83  */
84 struct rxrpc_jumbo_header {
85 	uint8_t		flags;		/* packet flags (as per rxrpc_header) */
86 	uint8_t		pad;
87 	__be16		_rsvd;		/* reserved (used by kerberos security as cksum) */
88 };
89 
90 #define RXRPC_JUMBO_DATALEN	1412	/* non-terminal jumbo packet data length */
91 
92 /*****************************************************************************/
93 /*
94  * on-the-wire Rx ACK packet data payload
95  * - all multibyte fields should be in network byte order
96  */
97 struct rxrpc_ackpacket {
98 	__be16		bufferSpace;	/* number of packet buffers available */
99 	__be16		maxSkew;	/* diff between serno being ACK'd and highest serial no
100 					 * received */
101 	__be32		firstPacket;	/* sequence no of first ACK'd packet in attached list */
102 	__be32		previousPacket;	/* sequence no of previous packet received */
103 	__be32		serial;		/* serial no of packet that prompted this ACK */
104 
105 	uint8_t		reason;		/* reason for ACK */
106 #define RXRPC_ACK_REQUESTED		1	/* ACK was requested on packet */
107 #define RXRPC_ACK_DUPLICATE		2	/* duplicate packet received */
108 #define RXRPC_ACK_OUT_OF_SEQUENCE	3	/* out of sequence packet received */
109 #define RXRPC_ACK_EXCEEDS_WINDOW	4	/* packet received beyond end of ACK window */
110 #define RXRPC_ACK_NOSPACE		5	/* packet discarded due to lack of buffer space */
111 #define RXRPC_ACK_PING			6	/* keep alive ACK */
112 #define RXRPC_ACK_PING_RESPONSE		7	/* response to RXRPC_ACK_PING */
113 #define RXRPC_ACK_DELAY			8	/* nothing happened since received packet */
114 #define RXRPC_ACK_IDLE			9	/* ACK due to fully received ACK window */
115 
116 	uint8_t		nAcks;		/* number of ACKs */
117 #define RXRPC_MAXACKS	255
118 
119 	uint8_t		acks[0];	/* list of ACK/NAKs */
120 #define RXRPC_ACK_TYPE_NACK		0
121 #define RXRPC_ACK_TYPE_ACK		1
122 
123 } __packed;
124 
125 /*
126  * ACK packets can have a further piece of information tagged on the end
127  */
128 struct rxrpc_ackinfo {
129 	__be32		rxMTU;		/* maximum Rx MTU size (bytes) [AFS 3.3] */
130 	__be32		maxMTU;		/* maximum interface MTU size (bytes) [AFS 3.3] */
131 	__be32		rwind;		/* Rx window size (packets) [AFS 3.4] */
132 	__be32		jumbo_max;	/* max packets to stick into a jumbo packet [AFS 3.5] */
133 };
134 
135 /*****************************************************************************/
136 /*
137  * Kerberos security type-2 challenge packet
138  */
139 struct rxkad_challenge {
140 	__be32		version;	/* version of this challenge type */
141 	__be32		nonce;		/* encrypted random number */
142 	__be32		min_level;	/* minimum security level */
143 	__be32		__padding;	/* padding to 8-byte boundary */
144 } __packed;
145 
146 /*****************************************************************************/
147 /*
148  * Kerberos security type-2 response packet
149  */
150 struct rxkad_response {
151 	__be32		version;	/* version of this response type */
152 	__be32		__pad;
153 
154 	/* encrypted bit of the response */
155 	struct {
156 		__be32		epoch;		/* current epoch */
157 		__be32		cid;		/* parent connection ID */
158 		__be32		checksum;	/* checksum */
159 		__be32		securityIndex;	/* security type */
160 		__be32		call_id[4];	/* encrypted call IDs */
161 		__be32		inc_nonce;	/* challenge nonce + 1 */
162 		__be32		level;		/* desired level */
163 	} encrypted;
164 
165 	__be32		kvno;		/* Kerberos key version number */
166 	__be32		ticket_len;	/* Kerberos ticket length  */
167 } __packed;
168 
169 /*****************************************************************************/
170 /*
171  * RxRPC-level abort codes
172  */
173 #define RX_CALL_DEAD		-1	/* call/conn has been inactive and is shut down */
174 #define RX_INVALID_OPERATION	-2	/* invalid operation requested / attempted */
175 #define RX_CALL_TIMEOUT		-3	/* call timeout exceeded */
176 #define RX_EOF			-4	/* unexpected end of data on read op */
177 #define RX_PROTOCOL_ERROR	-5	/* low-level protocol error */
178 #define RX_USER_ABORT		-6	/* generic user abort */
179 #define RX_ADDRINUSE		-7	/* UDP port in use */
180 #define RX_DEBUGI_BADTYPE	-8	/* bad debugging packet type */
181 
182 /*
183  * (un)marshalling abort codes (rxgen)
184  */
185 #define	RXGEN_CC_MARSHAL    -450
186 #define	RXGEN_CC_UNMARSHAL  -451
187 #define	RXGEN_SS_MARSHAL    -452
188 #define	RXGEN_SS_UNMARSHAL  -453
189 #define	RXGEN_DECODE	    -454
190 #define	RXGEN_OPCODE	    -455
191 #define	RXGEN_SS_XDRFREE    -456
192 #define	RXGEN_CC_XDRFREE    -457
193 
194 /*
195  * Rx kerberos security abort codes
196  * - unfortunately we have no generalised security abort codes to say things
197  *   like "unsupported security", so we have to use these instead and hope the
198  *   other side understands
199  */
200 #define RXKADINCONSISTENCY	19270400	/* security module structure inconsistent */
201 #define RXKADPACKETSHORT	19270401	/* packet too short for security challenge */
202 #define RXKADLEVELFAIL		19270402	/* security level negotiation failed */
203 #define RXKADTICKETLEN		19270403	/* ticket length too short or too long */
204 #define RXKADOUTOFSEQUENCE	19270404	/* packet had bad sequence number */
205 #define RXKADNOAUTH		19270405	/* caller not authorised */
206 #define RXKADBADKEY		19270406	/* illegal key: bad parity or weak */
207 #define RXKADBADTICKET		19270407	/* security object was passed a bad ticket */
208 #define RXKADUNKNOWNKEY		19270408	/* ticket contained unknown key version number */
209 #define RXKADEXPIRED		19270409	/* authentication expired */
210 #define RXKADSEALEDINCON	19270410	/* sealed data inconsistent */
211 #define RXKADDATALEN		19270411	/* user data too long */
212 #define RXKADILLEGALLEVEL	19270412	/* caller not authorised to use encrypted conns */
213 
214 #endif /* _LINUX_RXRPC_PACKET_H */
215