1/* SPDX-License-Identifier: GPL-2.0-or-later */ 2/* packet.h: Rx packet layout and definitions 3 * 4 * Copyright (C) 2002, 2007 Red Hat, Inc. All Rights Reserved. 5 * Written by David Howells (dhowells@redhat.com) 6 */ 7 8#ifndef _LINUX_RXRPC_PACKET_H 9#define _LINUX_RXRPC_PACKET_H 10 11typedef u32 rxrpc_seq_t; /* Rx message sequence number */ 12typedef u32 rxrpc_serial_t; /* Rx message serial number */ 13typedef __be32 rxrpc_seq_net_t; /* on-the-wire Rx message sequence number */ 14typedef __be32 rxrpc_serial_net_t; /* on-the-wire Rx message serial number */ 15 16/*****************************************************************************/ 17/* 18 * on-the-wire Rx packet header 19 * - all multibyte fields should be in network byte order 20 */ 21struct rxrpc_wire_header { 22 __be32 epoch; /* client boot timestamp */ 23#define RXRPC_RANDOM_EPOCH 0x80000000 /* Random if set, date-based if not */ 24 25 __be32 cid; /* connection and channel ID */ 26#define RXRPC_MAXCALLS 4 /* max active calls per conn */ 27#define RXRPC_CHANNELMASK (RXRPC_MAXCALLS-1) /* mask for channel ID */ 28#define RXRPC_CIDMASK (~RXRPC_CHANNELMASK) /* mask for connection ID */ 29#define RXRPC_CIDSHIFT ilog2(RXRPC_MAXCALLS) /* shift for connection ID */ 30#define RXRPC_CID_INC (1 << RXRPC_CIDSHIFT) /* connection ID increment */ 31 32 __be32 callNumber; /* call ID (0 for connection-level packets) */ 33 __be32 seq; /* sequence number of pkt in call stream */ 34 __be32 serial; /* serial number of pkt sent to network */ 35 36 uint8_t type; /* packet type */ 37#define RXRPC_PACKET_TYPE_DATA 1 /* data */ 38#define RXRPC_PACKET_TYPE_ACK 2 /* ACK */ 39#define RXRPC_PACKET_TYPE_BUSY 3 /* call reject */ 40#define RXRPC_PACKET_TYPE_ABORT 4 /* call/connection abort */ 41#define RXRPC_PACKET_TYPE_ACKALL 5 /* ACK all outstanding packets on call */ 42#define RXRPC_PACKET_TYPE_CHALLENGE 6 /* connection security challenge (SRVR->CLNT) */ 43#define RXRPC_PACKET_TYPE_RESPONSE 7 /* connection secutity response (CLNT->SRVR) */ 44#define RXRPC_PACKET_TYPE_DEBUG 8 /* debug info request */ 45#define RXRPC_PACKET_TYPE_PARAMS 9 /* Parameter negotiation (unspec'd, ignore) */ 46#define RXRPC_PACKET_TYPE_10 10 /* Ignored */ 47#define RXRPC_PACKET_TYPE_11 11 /* Ignored */ 48#define RXRPC_PACKET_TYPE_VERSION 13 /* version string request */ 49 50 uint8_t flags; /* packet flags */ 51#define RXRPC_CLIENT_INITIATED 0x01 /* signifies a packet generated by a client */ 52#define RXRPC_REQUEST_ACK 0x02 /* request an unconditional ACK of this packet */ 53#define RXRPC_LAST_PACKET 0x04 /* the last packet from this side for this call */ 54#define RXRPC_MORE_PACKETS 0x08 /* more packets to come */ 55#define RXRPC_JUMBO_PACKET 0x20 /* [DATA] this is a jumbo packet */ 56#define RXRPC_SLOW_START_OK 0x20 /* [ACK] slow start supported */ 57 58 uint8_t userStatus; /* app-layer defined status */ 59#define RXRPC_USERSTATUS_SERVICE_UPGRADE 0x01 /* AuriStor service upgrade request */ 60 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/*****************************************************************************/ 71/* 72 * jumbo packet secondary header 73 * - can be mapped to read header by: 74 * - new_serial = serial + 1 75 * - new_seq = seq + 1 76 * - new_flags = j_flags 77 * - new__rsvd = j__rsvd 78 * - duplicating all other fields 79 */ 80struct rxrpc_jumbo_header { 81 uint8_t flags; /* packet flags (as per rxrpc_header) */ 82 uint8_t pad; 83 union { 84 __be16 _rsvd; /* reserved */ 85 __be16 cksum; /* kerberos security checksum */ 86 }; 87} __packed; 88 89#define RXRPC_JUMBO_DATALEN 1412 /* non-terminal jumbo packet data length */ 90#define RXRPC_JUMBO_SUBPKTLEN (RXRPC_JUMBO_DATALEN + sizeof(struct rxrpc_jumbo_header)) 91 92/* 93 * The maximum number of subpackets that can possibly fit in a UDP packet is: 94 * 95 * ((max_IP - IP_hdr - UDP_hdr) / RXRPC_JUMBO_SUBPKTLEN) + 1 96 * = ((65535 - 28 - 28) / 1416) + 1 97 * = 46 non-terminal packets and 1 terminal packet. 98 */ 99#define RXRPC_MAX_NR_JUMBO 47 100 101/*****************************************************************************/ 102/* 103 * on-the-wire Rx ACK packet data payload 104 * - all multibyte fields should be in network byte order 105 */ 106struct rxrpc_ackpacket { 107 __be16 bufferSpace; /* number of packet buffers available */ 108 __be16 maxSkew; /* diff between serno being ACK'd and highest serial no 109 * received */ 110 __be32 firstPacket; /* sequence no of first ACK'd packet in attached list */ 111 __be32 previousPacket; /* sequence no of previous packet received */ 112 __be32 serial; /* serial no of packet that prompted this ACK */ 113 114 uint8_t reason; /* reason for ACK */ 115#define RXRPC_ACK_REQUESTED 1 /* ACK was requested on packet */ 116#define RXRPC_ACK_DUPLICATE 2 /* duplicate packet received */ 117#define RXRPC_ACK_OUT_OF_SEQUENCE 3 /* out of sequence packet received */ 118#define RXRPC_ACK_EXCEEDS_WINDOW 4 /* packet received beyond end of ACK window */ 119#define RXRPC_ACK_NOSPACE 5 /* packet discarded due to lack of buffer space */ 120#define RXRPC_ACK_PING 6 /* keep alive ACK */ 121#define RXRPC_ACK_PING_RESPONSE 7 /* response to RXRPC_ACK_PING */ 122#define RXRPC_ACK_DELAY 8 /* nothing happened since received packet */ 123#define RXRPC_ACK_IDLE 9 /* ACK due to fully received ACK window */ 124#define RXRPC_ACK__INVALID 10 /* Representation of invalid ACK reason */ 125 126 uint8_t nAcks; /* number of ACKs */ 127#define RXRPC_MAXACKS 255 128 129 uint8_t acks[]; /* list of ACK/NAKs */ 130#define RXRPC_ACK_TYPE_NACK 0 131#define RXRPC_ACK_TYPE_ACK 1 132 133} __packed; 134 135/* 136 * ACK packets can have a further piece of information tagged on the end 137 */ 138struct rxrpc_acktrailer { 139 __be32 maxMTU; /* maximum Rx MTU size (bytes) [AFS 3.3] */ 140 __be32 ifMTU; /* maximum interface MTU size (bytes) [AFS 3.3] */ 141 __be32 rwind; /* Rx window size (packets) [AFS 3.4] */ 142 __be32 jumbo_max; /* max packets to stick into a jumbo packet [AFS 3.5] */ 143}; 144 145/*****************************************************************************/ 146/* 147 * Kerberos security type-2 challenge packet 148 */ 149struct rxkad_challenge { 150 __be32 version; /* version of this challenge type */ 151 __be32 nonce; /* encrypted random number */ 152 __be32 min_level; /* minimum security level */ 153 __be32 __padding; /* padding to 8-byte boundary */ 154} __packed; 155 156/*****************************************************************************/ 157/* 158 * Kerberos security type-2 response packet 159 */ 160struct rxkad_response { 161 __be32 version; /* version of this response type */ 162 __be32 __pad; 163 164 /* encrypted bit of the response */ 165 struct { 166 __be32 epoch; /* current epoch */ 167 __be32 cid; /* parent connection ID */ 168 __be32 checksum; /* checksum */ 169 __be32 securityIndex; /* security type */ 170 __be32 call_id[4]; /* encrypted call IDs */ 171 __be32 inc_nonce; /* challenge nonce + 1 */ 172 __be32 level; /* desired level */ 173 } encrypted; 174 175 __be32 kvno; /* Kerberos key version number */ 176 __be32 ticket_len; /* Kerberos ticket length */ 177} __packed; 178 179#endif /* _LINUX_RXRPC_PACKET_H */ 180