include/rxrpc/packet.h

   1 /* packet.h: Rx packet layout and definitions
   2  *
   3  * Copyright (C) 2002 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 #include <rxrpc/types.h>
  16
  17 #define RXRPC_IPUDP_SIZE                28
  18 extern size_t RXRPC_MAX_PACKET_SIZE;
  19 #define RXRPC_MAX_PACKET_DATA_SIZE      (RXRPC_MAX_PACKET_SIZE - sizeof(struct rxrpc_header))
  20 #define RXRPC_LOCAL_PACKET_SIZE         RXRPC_MAX_PACKET_SIZE
  21 #define RXRPC_REMOTE_PACKET_SIZE        (576 - RXRPC_IPUDP_SIZE)
  22
  23 /*****************************************************************************/
  24 /*
  25  * on-the-wire Rx packet header
  26  * - all multibyte fields should be in network byte order
  27  */
  28 struct rxrpc_header
  29 {
  30         __be32          epoch;          /* client boot timestamp */
  31
  32         __be32          cid;            /* connection and channel ID */
  33 #define RXRPC_MAXCALLS          4                       /* max active calls per conn */
  34 #define RXRPC_CHANNELMASK       (RXRPC_MAXCALLS-1)      /* mask for channel ID */
  35 #define RXRPC_CIDMASK           (~RXRPC_CHANNELMASK)    /* mask for connection ID */
  36 #define RXRPC_CIDSHIFT          ilog2(RXRPC_MAXCALLS)   /* shift for connection ID */
  37 #define RXRPC_CID_INC           (1 << RXRPC_CIDSHIFT)   /* connection ID increment */
  38
  39         __be32          callNumber;     /* call ID (0 for connection-level packets) */
  40 #define RXRPC_PROCESS_MAXCALLS  (1<<2)  /* maximum number of active calls per conn (power of 2) */
  41
  42         __be32          seq;            /* sequence number of pkt in call stream */
  43         __be32          serial;         /* serial number of pkt sent to network */
  44
  45         uint8_t         type;           /* packet type */
  46 #define RXRPC_PACKET_TYPE_DATA          1       /* data */
  47 #define RXRPC_PACKET_TYPE_ACK           2       /* ACK */
  48 #define RXRPC_PACKET_TYPE_BUSY          3       /* call reject */
  49 #define RXRPC_PACKET_TYPE_ABORT         4       /* call/connection abort */
  50 #define RXRPC_PACKET_TYPE_ACKALL        5       /* ACK all outstanding packets on call */
  51 #define RXRPC_PACKET_TYPE_CHALLENGE     6       /* connection security challenge (SRVR->CLNT) */
  52 #define RXRPC_PACKET_TYPE_RESPONSE      7       /* connection secutity response (CLNT->SRVR) */
  53 #define RXRPC_PACKET_TYPE_DEBUG         8       /* debug info request */
  54 #define RXRPC_N_PACKET_TYPES            9       /* number of packet types (incl type 0) */
  55
  56         uint8_t         flags;          /* packet flags */
  57 #define RXRPC_CLIENT_INITIATED  0x01            /* signifies a packet generated by a client */
  58 #define RXRPC_REQUEST_ACK       0x02            /* request an unconditional ACK of this packet */
  59 #define RXRPC_LAST_PACKET       0x04            /* the last packet from this side for this call */
  60 #define RXRPC_MORE_PACKETS      0x08            /* more packets to come */
  61 #define RXRPC_JUMBO_PACKET      0x20            /* [DATA] this is a jumbo packet */
  62 #define RXRPC_SLOW_START_OK     0x20            /* [ACK] slow start supported */
  63
  64         uint8_t         userStatus;     /* app-layer defined status */
  65         uint8_t         securityIndex;  /* security protocol ID */
  66         union {
  67                 __be16  _rsvd;          /* reserved */
  68                 __be16  cksum;          /* kerberos security checksum */
  69         };
  70         __be16          serviceId;      /* service ID */
  71
  72 } __attribute__((packed));
  73
  74 #define __rxrpc_header_off(X) offsetof(struct rxrpc_header,X)
  75
  76 extern const char *rxrpc_pkts[];
  77
  78 /*****************************************************************************/
  79 /*
  80  * jumbo packet secondary header
  81  * - can be mapped to read header by:
  82  *   - new_serial = serial + 1
  83  *   - new_seq = seq + 1
  84  *   - new_flags = j_flags
  85  *   - new__rsvd = j__rsvd
  86  *   - duplicating all other fields
  87  */
  88 struct rxrpc_jumbo_header
  89 {
  90         uint8_t         flags;          /* packet flags (as per rxrpc_header) */
  91         uint8_t         pad;
  92         __be16          _rsvd;          /* reserved (used by kerberos security as cksum) */
  93 };
  94
  95 #define RXRPC_JUMBO_DATALEN     1412    /* non-terminal jumbo packet data length */
  96
  97 /*****************************************************************************/
  98 /*
  99  * on-the-wire Rx ACK packet data payload
 100  * - all multibyte fields should be in network byte order
 101  */
 102 struct rxrpc_ackpacket
 103 {
 104         __be16          bufferSpace;    /* number of packet buffers available */
 105         __be16          maxSkew;        /* diff between serno being ACK'd and highest serial no
 106                                          * received */
 107         __be32          firstPacket;    /* sequence no of first ACK'd packet in attached list */
 108         __be32          previousPacket; /* sequence no of previous packet received */
 109         __be32          serial;         /* serial no of packet that prompted this ACK */
 110
 111         uint8_t         reason;         /* reason for ACK */
 112 #define RXRPC_ACK_REQUESTED             1       /* ACK was requested on packet */
 113 #define RXRPC_ACK_DUPLICATE             2       /* duplicate packet received */
 114 #define RXRPC_ACK_OUT_OF_SEQUENCE       3       /* out of sequence packet received */
 115 #define RXRPC_ACK_EXCEEDS_WINDOW        4       /* packet received beyond end of ACK window */
 116 #define RXRPC_ACK_NOSPACE               5       /* packet discarded due to lack of buffer space */
 117 #define RXRPC_ACK_PING                  6       /* keep alive ACK */
 118 #define RXRPC_ACK_PING_RESPONSE         7       /* response to RXRPC_ACK_PING */
 119 #define RXRPC_ACK_DELAY                 8       /* nothing happened since received packet */
 120 #define RXRPC_ACK_IDLE                  9       /* ACK due to fully received ACK window */
 121
 122         uint8_t         nAcks;          /* number of ACKs */
 123 #define RXRPC_MAXACKS   255
 124
 125         uint8_t         acks[0];        /* list of ACK/NAKs */
 126 #define RXRPC_ACK_TYPE_NACK             0
 127 #define RXRPC_ACK_TYPE_ACK              1
 128
 129 } __attribute__((packed));
 130
 131 /*
 132  * ACK packets can have a further piece of information tagged on the end
 133  */
 134 struct rxrpc_ackinfo {
 135         __be32          rxMTU;          /* maximum Rx MTU size (bytes) [AFS 3.3] */
 136         __be32          maxMTU;         /* maximum interface MTU size (bytes) [AFS 3.3] */
 137         __be32          rwind;          /* Rx window size (packets) [AFS 3.4] */
 138         __be32          jumbo_max;      /* max packets to stick into a jumbo packet [AFS 3.5] */
 139 };
 140
 141 /*****************************************************************************/
 142 /*
 143  * Kerberos security type-2 challenge packet
 144  */
 145 struct rxkad_challenge {
 146         __be32          version;        /* version of this challenge type */
 147         __be32          nonce;          /* encrypted random number */
 148         __be32          min_level;      /* minimum security level */
 149         __be32          __padding;      /* padding to 8-byte boundary */
 150 } __attribute__((packed));
 151
 152 /*****************************************************************************/
 153 /*
 154  * Kerberos security type-2 response packet
 155  */
 156 struct rxkad_response {
 157         __be32          version;        /* version of this reponse type */
 158         __be32          __pad;
 159
 160         /* encrypted bit of the response */
 161         struct {
 162                 __be32          epoch;          /* current epoch */
 163                 __be32          cid;            /* parent connection ID */
 164                 __be32          checksum;       /* checksum */
 165                 __be32          securityIndex;  /* security type */
 166                 __be32          call_id[4];     /* encrypted call IDs */
 167                 __be32          inc_nonce;      /* challenge nonce + 1 */
 168                 __be32          level;          /* desired level */
 169         } encrypted;
 170
 171         __be32          kvno;           /* Kerberos key version number */
 172         __be32          ticket_len;     /* Kerberos ticket length  */
 173 } __attribute__((packed));
 174
 175 /*****************************************************************************/
 176 /*
 177  * RxRPC-level abort codes
 178  */
 179 #define RX_CALL_DEAD            -1      /* call/conn has been inactive and is shut down */
 180 #define RX_INVALID_OPERATION    -2      /* invalid operation requested / attempted */
 181 #define RX_CALL_TIMEOUT         -3      /* call timeout exceeded */
 182 #define RX_EOF                  -4      /* unexpected end of data on read op */
 183 #define RX_PROTOCOL_ERROR       -5      /* low-level protocol error */
 184 #define RX_USER_ABORT           -6      /* generic user abort */
 185 #define RX_ADDRINUSE            -7      /* UDP port in use */
 186 #define RX_DEBUGI_BADTYPE       -8      /* bad debugging packet type */
 187
 188 /*
 189  * Rx kerberos security abort codes
 190  * - unfortunately we have no generalised security abort codes to say things
 191  *   like "unsupported security", so we have to use these instead and hope the
 192  *   other side understands
 193  */
 194 #define RXKADINCONSISTENCY      19270400        /* security module structure inconsistent */
 195 #define RXKADPACKETSHORT        19270401        /* packet too short for security challenge */
 196 #define RXKADLEVELFAIL          19270402        /* security level negotiation failed */
 197 #define RXKADTICKETLEN          19270403        /* ticket length too short or too long */
 198 #define RXKADOUTOFSEQUENCE      19270404        /* packet had bad sequence number */
 199 #define RXKADNOAUTH             19270405        /* caller not authorised */
 200 #define RXKADBADKEY             19270406        /* illegal key: bad parity or weak */
 201 #define RXKADBADTICKET          19270407        /* security object was passed a bad ticket */
 202 #define RXKADUNKNOWNKEY         19270408        /* ticket contained unknown key version number */
 203 #define RXKADEXPIRED            19270409        /* authentication expired */
 204 #define RXKADSEALEDINCON        19270410        /* sealed data inconsistent */
 205 #define RXKADDATALEN            19270411        /* user data too long */
 206 #define RXKADILLEGALLEVEL       19270412        /* caller not authorised to use encrypted conns */
 207
 208 #endif /* _LINUX_RXRPC_PACKET_H */