lib/sflow.h

   1 /* Copyright (c) 2002-2009 InMon Corp. Licensed under the terms of the InMon sFlow licence: */
   2 /* http://www.inmon.com/technology/sflowlicense.txt */
   3
   4 #ifndef SFLOW_H
   5 #define SFLOW_H 1
   6
   7 enum SFLAddress_type {
   8     SFLADDRESSTYPE_IP_V4 = 1,
   9     SFLADDRESSTYPE_IP_V6 = 2
  10 };
  11
  12 typedef struct {
  13     u_int32_t addr;
  14 } SFLIPv4;
  15
  16 typedef struct {
  17     u_char addr[16];
  18 } SFLIPv6;
  19
  20 typedef union _SFLAddress_value {
  21     SFLIPv4 ip_v4;
  22     SFLIPv6 ip_v6;
  23 } SFLAddress_value;
  24
  25 typedef struct _SFLAddress {
  26     u_int32_t type;           /* enum SFLAddress_type */
  27     SFLAddress_value address;
  28 } SFLAddress;
  29
  30 /* Packet header data */
  31
  32 #define SFL_DEFAULT_HEADER_SIZE 128
  33 #define SFL_DEFAULT_COLLECTOR_PORT 6343
  34 #define SFL_DEFAULT_SAMPLING_RATE 400
  35 #define SFL_DEFAULT_POLLING_INTERVAL 30
  36
  37 /* The header protocol describes the format of the sampled header */
  38 enum SFLHeader_protocol {
  39     SFLHEADER_ETHERNET_ISO8023     = 1,
  40     SFLHEADER_ISO88024_TOKENBUS    = 2,
  41     SFLHEADER_ISO88025_TOKENRING   = 3,
  42     SFLHEADER_FDDI                 = 4,
  43     SFLHEADER_FRAME_RELAY          = 5,
  44     SFLHEADER_X25                  = 6,
  45     SFLHEADER_PPP                  = 7,
  46     SFLHEADER_SMDS                 = 8,
  47     SFLHEADER_AAL5                 = 9,
  48     SFLHEADER_AAL5_IP              = 10, /* e.g. Cisco AAL5 mux */
  49     SFLHEADER_IPv4                 = 11,
  50     SFLHEADER_IPv6                 = 12,
  51     SFLHEADER_MPLS                 = 13
  52 };
  53
  54 /* raw sampled header */
  55
  56 typedef struct _SFLSampled_header {
  57     u_int32_t header_protocol;            /* (enum SFLHeader_protocol) */
  58     u_int32_t frame_length;               /* Original length of packet before sampling */
  59     u_int32_t stripped;                   /* header/trailer bytes stripped by sender */
  60     u_int32_t header_length;              /* length of sampled header bytes to follow */
  61     u_int8_t *header_bytes;               /* Header bytes */
  62 } SFLSampled_header;
  63
  64 /* decoded ethernet header */
  65
  66 typedef struct _SFLSampled_ethernet {
  67     u_int32_t eth_len;       /* The length of the MAC packet excluding
  68                                 lower layer encapsulations */
  69     u_int8_t src_mac[8];    /* 6 bytes + 2 pad */
  70     u_int8_t dst_mac[8];
  71     u_int32_t eth_type;
  72 } SFLSampled_ethernet;
  73
  74 /* decoded IP version 4 header */
  75
  76 typedef struct _SFLSampled_ipv4 {
  77     u_int32_t length;      /* The length of the IP packet
  78                               excluding lower layer encapsulations */
  79     u_int32_t protocol;    /* IP Protocol type (for example, TCP = 6, UDP = 17) */
  80     SFLIPv4   src_ip;      /* Source IP Address */
  81     SFLIPv4   dst_ip;      /* Destination IP Address */
  82     u_int32_t src_port;    /* TCP/UDP source port number or equivalent */
  83     u_int32_t dst_port;    /* TCP/UDP destination port number or equivalent */
  84     u_int32_t tcp_flags;   /* TCP flags */
  85     u_int32_t tos;         /* IP type of service */
  86 } SFLSampled_ipv4;
  87
  88 /* decoded IP version 6 data */
  89
  90 typedef struct _SFLSampled_ipv6 {
  91     u_int32_t length;       /* The length of the IP packet
  92                                excluding lower layer encapsulations */
  93     u_int32_t protocol;     /* IP Protocol type (for example, TCP = 6, UDP = 17) */
  94     SFLIPv6   src_ip;       /* Source IP Address */
  95     SFLIPv6   dst_ip;       /* Destination IP Address */
  96     u_int32_t src_port;     /* TCP/UDP source port number or equivalent */
  97     u_int32_t dst_port;     /* TCP/UDP destination port number or equivalent */
  98     u_int32_t tcp_flags;    /* TCP flags */
  99     u_int32_t priority;     /* IP priority */
 100 } SFLSampled_ipv6;
 101
 102 /* Extended data types */
 103
 104 /* Extended switch data */
 105
 106 typedef struct _SFLExtended_switch {
 107     u_int32_t src_vlan;       /* The 802.1Q VLAN id of incomming frame */
 108     u_int32_t src_priority;   /* The 802.1p priority */
 109     u_int32_t dst_vlan;       /* The 802.1Q VLAN id of outgoing frame */
 110     u_int32_t dst_priority;   /* The 802.1p priority */
 111 } SFLExtended_switch;
 112
 113 /* Extended router data */
 114
 115 typedef struct _SFLExtended_router {
 116     SFLAddress nexthop;               /* IP address of next hop router */
 117     u_int32_t src_mask;               /* Source address prefix mask bits */
 118     u_int32_t dst_mask;               /* Destination address prefix mask bits */
 119 } SFLExtended_router;
 120
 121 /* Extended gateway data */
 122 enum SFLExtended_as_path_segment_type {
 123     SFLEXTENDED_AS_SET = 1,      /* Unordered set of ASs */
 124     SFLEXTENDED_AS_SEQUENCE = 2  /* Ordered sequence of ASs */
 125 };
 126
 127 typedef struct _SFLExtended_as_path_segment {
 128     u_int32_t type;   /* enum SFLExtended_as_path_segment_type */
 129     u_int32_t length; /* number of AS numbers in set/sequence */
 130     union {
 131         u_int32_t *set;
 132         u_int32_t *seq;
 133     } as;
 134 } SFLExtended_as_path_segment;
 135
 136 typedef struct _SFLExtended_gateway {
 137     SFLAddress nexthop;                       /* Address of the border router that should
 138                                                  be used for the destination network */
 139     u_int32_t as;                             /* AS number for this gateway */
 140     u_int32_t src_as;                         /* AS number of source (origin) */
 141     u_int32_t src_peer_as;                    /* AS number of source peer */
 142     u_int32_t dst_as_path_segments;           /* number of segments in path */
 143     SFLExtended_as_path_segment *dst_as_path; /* list of seqs or sets */
 144     u_int32_t communities_length;             /* number of communities */
 145     u_int32_t *communities;                   /* set of communities */
 146     u_int32_t localpref;                      /* LocalPref associated with this route */
 147 } SFLExtended_gateway;
 148
 149 typedef struct _SFLString {
 150     u_int32_t len;
 151     char *str;
 152 } SFLString;
 153
 154 /* Extended user data */
 155
 156 typedef struct _SFLExtended_user {
 157     u_int32_t src_charset;  /* MIBEnum value of character set used to encode a string - See RFC 2978
 158                                Where possible UTF-8 encoding (MIBEnum=106) should be used. A value
 159                                of zero indicates an unknown encoding. */
 160     SFLString src_user;
 161     u_int32_t dst_charset;
 162     SFLString dst_user;
 163 } SFLExtended_user;
 164
 165 /* Extended URL data */
 166
 167 enum SFLExtended_url_direction {
 168     SFLEXTENDED_URL_SRC = 1, /* URL is associated with source address */
 169     SFLEXTENDED_URL_DST = 2  /* URL is associated with destination address */
 170 };
 171
 172 typedef struct _SFLExtended_url {
 173     u_int32_t direction;   /* enum SFLExtended_url_direction */
 174     SFLString url;         /* URL associated with the packet flow.
 175                               Must be URL encoded */
 176     SFLString host;        /* The host field from the HTTP header */
 177 } SFLExtended_url;
 178
 179 /* Extended MPLS data */
 180
 181 typedef struct _SFLLabelStack {
 182     u_int32_t depth;
 183     u_int32_t *stack; /* first entry is top of stack - see RFC 3032 for encoding */
 184 } SFLLabelStack;
 185
 186 typedef struct _SFLExtended_mpls {
 187     SFLAddress nextHop;        /* Address of the next hop */
 188     SFLLabelStack in_stack;
 189     SFLLabelStack out_stack;
 190 } SFLExtended_mpls;
 191
 192 /* Extended NAT data
 193    Packet header records report addresses as seen at the sFlowDataSource.
 194    The extended_nat structure reports on translated source and/or destination
 195    addesses for this packet. If an address was not translated it should
 196    be equal to that reported for the header. */
 197
 198 typedef struct _SFLExtended_nat {
 199     SFLAddress src;    /* Source address */
 200     SFLAddress dst;    /* Destination address */
 201 } SFLExtended_nat;
 202
 203 /* additional Extended MPLS stucts */
 204
 205 typedef struct _SFLExtended_mpls_tunnel {
 206     SFLString tunnel_lsp_name;  /* Tunnel name */
 207     u_int32_t tunnel_id;        /* Tunnel ID */
 208     u_int32_t tunnel_cos;       /* Tunnel COS value */
 209 } SFLExtended_mpls_tunnel;
 210
 211 typedef struct _SFLExtended_mpls_vc {
 212     SFLString vc_instance_name; /* VC instance name */
 213     u_int32_t vll_vc_id;        /* VLL/VC instance ID */
 214     u_int32_t vc_label_cos;     /* VC Label COS value */
 215 } SFLExtended_mpls_vc;
 216
 217 /* Extended MPLS FEC
 218    - Definitions from MPLS-FTN-STD-MIB mplsFTNTable */
 219
 220 typedef struct _SFLExtended_mpls_FTN {
 221     SFLString mplsFTNDescr;
 222     u_int32_t mplsFTNMask;
 223 } SFLExtended_mpls_FTN;
 224
 225 /* Extended MPLS LVP FEC
 226    - Definition from MPLS-LDP-STD-MIB mplsFecTable
 227    Note: mplsFecAddrType, mplsFecAddr information available
 228    from packet header */
 229
 230 typedef struct _SFLExtended_mpls_LDP_FEC {
 231     u_int32_t mplsFecAddrPrefixLength;
 232 } SFLExtended_mpls_LDP_FEC;
 233
 234 /* Extended VLAN tunnel information
 235    Record outer VLAN encapsulations that have
 236    been stripped. extended_vlantunnel information
 237    should only be reported if all the following conditions are satisfied:
 238    1. The packet has nested vlan tags, AND
 239    2. The reporting device is VLAN aware, AND
 240    3. One or more VLAN tags have been stripped, either
 241    because they represent proprietary encapsulations, or
 242    because switch hardware automatically strips the outer VLAN
 243    encapsulation.
 244    Reporting extended_vlantunnel information is not a substitute for
 245    reporting extended_switch information. extended_switch data must
 246    always be reported to describe the ingress/egress VLAN information
 247    for the packet. The extended_vlantunnel information only applies to
 248    nested VLAN tags, and then only when one or more tags has been
 249    stripped. */
 250
 251 typedef SFLLabelStack SFLVlanStack;
 252 typedef struct _SFLExtended_vlan_tunnel {
 253     SFLVlanStack stack;  /* List of stripped 802.1Q TPID/TCI layers. Each
 254                             TPID,TCI pair is represented as a single 32 bit
 255                             integer. Layers listed from outermost to
 256                             innermost. */
 257 } SFLExtended_vlan_tunnel;
 258
 259 enum SFLFlow_type_tag {
 260     /* enterprise = 0, format = ... */
 261     SFLFLOW_HEADER    = 1,      /* Packet headers are sampled */
 262     SFLFLOW_ETHERNET  = 2,      /* MAC layer information */
 263     SFLFLOW_IPV4      = 3,      /* IP version 4 data */
 264     SFLFLOW_IPV6      = 4,      /* IP version 6 data */
 265     SFLFLOW_EX_SWITCH    = 1001,      /* Extended switch information */
 266     SFLFLOW_EX_ROUTER    = 1002,      /* Extended router information */
 267     SFLFLOW_EX_GATEWAY   = 1003,      /* Extended gateway router information */
 268     SFLFLOW_EX_USER      = 1004,      /* Extended TACAS/RADIUS user information */
 269     SFLFLOW_EX_URL       = 1005,      /* Extended URL information */
 270     SFLFLOW_EX_MPLS      = 1006,      /* Extended MPLS information */
 271     SFLFLOW_EX_NAT       = 1007,      /* Extended NAT information */
 272     SFLFLOW_EX_MPLS_TUNNEL  = 1008,   /* additional MPLS information */
 273     SFLFLOW_EX_MPLS_VC      = 1009,
 274     SFLFLOW_EX_MPLS_FTN     = 1010,
 275     SFLFLOW_EX_MPLS_LDP_FEC = 1011,
 276     SFLFLOW_EX_VLAN_TUNNEL  = 1012,   /* VLAN stack */
 277 };
 278
 279 typedef union _SFLFlow_type {
 280     SFLSampled_header header;
 281     SFLSampled_ethernet ethernet;
 282     SFLSampled_ipv4 ipv4;
 283     SFLSampled_ipv6 ipv6;
 284     SFLExtended_switch sw;
 285     SFLExtended_router router;
 286     SFLExtended_gateway gateway;
 287     SFLExtended_user user;
 288     SFLExtended_url url;
 289     SFLExtended_mpls mpls;
 290     SFLExtended_nat nat;
 291     SFLExtended_mpls_tunnel mpls_tunnel;
 292     SFLExtended_mpls_vc mpls_vc;
 293     SFLExtended_mpls_FTN mpls_ftn;
 294     SFLExtended_mpls_LDP_FEC mpls_ldp_fec;
 295     SFLExtended_vlan_tunnel vlan_tunnel;
 296 } SFLFlow_type;
 297
 298 typedef struct _SFLFlow_sample_element {
 299     struct _SFLFlow_sample_element *nxt;
 300     u_int32_t tag;  /* SFLFlow_type_tag */
 301     u_int32_t length;
 302     SFLFlow_type flowType;
 303 } SFLFlow_sample_element;
 304
 305 enum SFL_sample_tag {
 306     SFLFLOW_SAMPLE = 1,              /* enterprise = 0 : format = 1 */
 307     SFLCOUNTERS_SAMPLE = 2,          /* enterprise = 0 : format = 2 */
 308     SFLFLOW_SAMPLE_EXPANDED = 3,     /* enterprise = 0 : format = 3 */
 309     SFLCOUNTERS_SAMPLE_EXPANDED = 4  /* enterprise = 0 : format = 4 */
 310 };
 311
 312 /* Format of a single flow sample */
 313
 314 typedef struct _SFLFlow_sample {
 315     /* u_int32_t tag;    */         /* SFL_sample_tag -- enterprise = 0 : format = 1 */
 316     /* u_int32_t length; */
 317     u_int32_t sequence_number;      /* Incremented with each flow sample
 318                                        generated */
 319     u_int32_t source_id;            /* fsSourceId */
 320     u_int32_t sampling_rate;        /* fsPacketSamplingRate */
 321     u_int32_t sample_pool;          /* Total number of packets that could have been
 322                                        sampled (i.e. packets skipped by sampling
 323                                        process + total number of samples) */
 324     u_int32_t drops;                /* Number of times a packet was dropped due to
 325                                        lack of resources */
 326     u_int32_t input;                /* SNMP ifIndex of input interface.
 327                                        0 if interface is not known. */
 328     u_int32_t output;               /* SNMP ifIndex of output interface,
 329                                        0 if interface is not known.
 330                                        Set most significant bit to indicate
 331                                        multiple destination interfaces
 332                                        (i.e. in case of broadcast or multicast)
 333                                        and set lower order bits to indicate
 334                                        number of destination interfaces.
 335                                        Examples:
 336                                        0x00000002  indicates ifIndex = 2
 337                                        0x00000000  ifIndex unknown.
 338                                        0x80000007  indicates a packet sent
 339                                        to 7 interfaces.
 340                                        0x80000000  indicates a packet sent to
 341                                        an unknown number of
 342                                        interfaces greater than 1.*/
 343     u_int32_t num_elements;
 344     SFLFlow_sample_element *elements;
 345 } SFLFlow_sample;
 346
 347 /* same thing, but the expanded version (for full 32-bit ifIndex numbers) */
 348
 349 typedef struct _SFLFlow_sample_expanded {
 350     /* u_int32_t tag;    */         /* SFL_sample_tag -- enterprise = 0 : format = 1 */
 351     /* u_int32_t length; */
 352     u_int32_t sequence_number;      /* Incremented with each flow sample
 353                                        generated */
 354     u_int32_t ds_class;             /* EXPANDED */
 355     u_int32_t ds_index;             /* EXPANDED */
 356     u_int32_t sampling_rate;        /* fsPacketSamplingRate */
 357     u_int32_t sample_pool;          /* Total number of packets that could have been
 358                                        sampled (i.e. packets skipped by sampling
 359                                        process + total number of samples) */
 360     u_int32_t drops;                /* Number of times a packet was dropped due to
 361                                        lack of resources */
 362     u_int32_t inputFormat;          /* EXPANDED */
 363     u_int32_t input;                /* SNMP ifIndex of input interface.
 364                                        0 if interface is not known. */
 365     u_int32_t outputFormat;         /* EXPANDED */
 366     u_int32_t output;               /* SNMP ifIndex of output interface,
 367                                        0 if interface is not known. */
 368     u_int32_t num_elements;
 369     SFLFlow_sample_element *elements;
 370 } SFLFlow_sample_expanded;
 371
 372 /* Counter types */
 373
 374 /* Generic interface counters - see RFC 1573, 2233 */
 375
 376 typedef struct _SFLIf_counters {
 377     u_int32_t ifIndex;
 378     u_int32_t ifType;
 379     u_int64_t ifSpeed;
 380     u_int32_t ifDirection;        /* Derived from MAU MIB (RFC 2668)
 381                                      0 = unknown, 1 = full-duplex,
 382                                      2 = half-duplex, 3 = in, 4 = out */
 383     u_int32_t ifStatus;           /* bit field with the following bits assigned:
 384                                      bit 0 = ifAdminStatus (0 = down, 1 = up)
 385                                      bit 1 = ifOperStatus (0 = down, 1 = up) */
 386     u_int64_t ifInOctets;
 387     u_int32_t ifInUcastPkts;
 388     u_int32_t ifInMulticastPkts;
 389     u_int32_t ifInBroadcastPkts;
 390     u_int32_t ifInDiscards;
 391     u_int32_t ifInErrors;
 392     u_int32_t ifInUnknownProtos;
 393     u_int64_t ifOutOctets;
 394     u_int32_t ifOutUcastPkts;
 395     u_int32_t ifOutMulticastPkts;
 396     u_int32_t ifOutBroadcastPkts;
 397     u_int32_t ifOutDiscards;
 398     u_int32_t ifOutErrors;
 399     u_int32_t ifPromiscuousMode;
 400 } SFLIf_counters;
 401
 402 /* Ethernet interface counters - see RFC 2358 */
 403 typedef struct _SFLEthernet_counters {
 404     u_int32_t dot3StatsAlignmentErrors;
 405     u_int32_t dot3StatsFCSErrors;
 406     u_int32_t dot3StatsSingleCollisionFrames;
 407     u_int32_t dot3StatsMultipleCollisionFrames;
 408     u_int32_t dot3StatsSQETestErrors;
 409     u_int32_t dot3StatsDeferredTransmissions;
 410     u_int32_t dot3StatsLateCollisions;
 411     u_int32_t dot3StatsExcessiveCollisions;
 412     u_int32_t dot3StatsInternalMacTransmitErrors;
 413     u_int32_t dot3StatsCarrierSenseErrors;
 414     u_int32_t dot3StatsFrameTooLongs;
 415     u_int32_t dot3StatsInternalMacReceiveErrors;
 416     u_int32_t dot3StatsSymbolErrors;
 417 } SFLEthernet_counters;
 418
 419 /* Token ring counters - see RFC 1748 */
 420
 421 typedef struct _SFLTokenring_counters {
 422     u_int32_t dot5StatsLineErrors;
 423     u_int32_t dot5StatsBurstErrors;
 424     u_int32_t dot5StatsACErrors;
 425     u_int32_t dot5StatsAbortTransErrors;
 426     u_int32_t dot5StatsInternalErrors;
 427     u_int32_t dot5StatsLostFrameErrors;
 428     u_int32_t dot5StatsReceiveCongestions;
 429     u_int32_t dot5StatsFrameCopiedErrors;
 430     u_int32_t dot5StatsTokenErrors;
 431     u_int32_t dot5StatsSoftErrors;
 432     u_int32_t dot5StatsHardErrors;
 433     u_int32_t dot5StatsSignalLoss;
 434     u_int32_t dot5StatsTransmitBeacons;
 435     u_int32_t dot5StatsRecoverys;
 436     u_int32_t dot5StatsLobeWires;
 437     u_int32_t dot5StatsRemoves;
 438     u_int32_t dot5StatsSingles;
 439     u_int32_t dot5StatsFreqErrors;
 440 } SFLTokenring_counters;
 441
 442 /* 100 BaseVG interface counters - see RFC 2020 */
 443
 444 typedef struct _SFLVg_counters {
 445     u_int32_t dot12InHighPriorityFrames;
 446     u_int64_t dot12InHighPriorityOctets;
 447     u_int32_t dot12InNormPriorityFrames;
 448     u_int64_t dot12InNormPriorityOctets;
 449     u_int32_t dot12InIPMErrors;
 450     u_int32_t dot12InOversizeFrameErrors;
 451     u_int32_t dot12InDataErrors;
 452     u_int32_t dot12InNullAddressedFrames;
 453     u_int32_t dot12OutHighPriorityFrames;
 454     u_int64_t dot12OutHighPriorityOctets;
 455     u_int32_t dot12TransitionIntoTrainings;
 456     u_int64_t dot12HCInHighPriorityOctets;
 457     u_int64_t dot12HCInNormPriorityOctets;
 458     u_int64_t dot12HCOutHighPriorityOctets;
 459 } SFLVg_counters;
 460
 461 typedef struct _SFLVlan_counters {
 462     u_int32_t vlan_id;
 463     u_int64_t octets;
 464     u_int32_t ucastPkts;
 465     u_int32_t multicastPkts;
 466     u_int32_t broadcastPkts;
 467     u_int32_t discards;
 468 } SFLVlan_counters;
 469
 470 /* Counters data */
 471
 472 enum SFLCounters_type_tag {
 473     /* enterprise = 0, format = ... */
 474     SFLCOUNTERS_GENERIC      = 1,
 475     SFLCOUNTERS_ETHERNET     = 2,
 476     SFLCOUNTERS_TOKENRING    = 3,
 477     SFLCOUNTERS_VG           = 4,
 478     SFLCOUNTERS_VLAN         = 5
 479 };
 480
 481 typedef union _SFLCounters_type {
 482     SFLIf_counters generic;
 483     SFLEthernet_counters ethernet;
 484     SFLTokenring_counters tokenring;
 485     SFLVg_counters vg;
 486     SFLVlan_counters vlan;
 487 } SFLCounters_type;
 488
 489 typedef struct _SFLCounters_sample_element {
 490     struct _SFLCounters_sample_element *nxt; /* linked list */
 491     u_int32_t tag; /* SFLCounters_type_tag */
 492     u_int32_t length;
 493     SFLCounters_type counterBlock;
 494 } SFLCounters_sample_element;
 495
 496 typedef struct _SFLCounters_sample {
 497     /* u_int32_t tag;    */       /* SFL_sample_tag -- enterprise = 0 : format = 2 */
 498     /* u_int32_t length; */
 499     u_int32_t sequence_number;    /* Incremented with each counters sample
 500                                      generated by this source_id */
 501     u_int32_t source_id;          /* fsSourceId */
 502     u_int32_t num_elements;
 503     SFLCounters_sample_element *elements;
 504 } SFLCounters_sample;
 505
 506 /* same thing, but the expanded version, so ds_index can be a full 32 bits */
 507 typedef struct _SFLCounters_sample_expanded {
 508     /* u_int32_t tag;    */       /* SFL_sample_tag -- enterprise = 0 : format = 2 */
 509     /* u_int32_t length; */
 510     u_int32_t sequence_number;    /* Incremented with each counters sample
 511                                      generated by this source_id */
 512     u_int32_t ds_class;           /* EXPANDED */
 513     u_int32_t ds_index;           /* EXPANDED */
 514     u_int32_t num_elements;
 515     SFLCounters_sample_element *elements;
 516 } SFLCounters_sample_expanded;
 517
 518 #define SFLADD_ELEMENT(_sm, _el) do { (_el)->nxt = (_sm)->elements; (_sm)->elements = (_el); } while(0)
 519
 520 /* Format of a sample datagram */
 521
 522 enum SFLDatagram_version {
 523     SFLDATAGRAM_VERSION2 = 2,
 524     SFLDATAGRAM_VERSION4 = 4,
 525     SFLDATAGRAM_VERSION5 = 5
 526 };
 527
 528 typedef struct _SFLSample_datagram_hdr {
 529     u_int32_t datagram_version;      /* (enum SFLDatagram_version) = VERSION5 = 5 */
 530     SFLAddress agent_address;        /* IP address of sampling agent */
 531     u_int32_t sub_agent_id;          /* Used to distinguishing between datagram
 532                                         streams from separate agent sub entities
 533                                         within an device. */
 534     u_int32_t sequence_number;       /* Incremented with each sample datagram
 535                                         generated */
 536     u_int32_t uptime;                /* Current time (in milliseconds since device
 537                                         last booted). Should be set as close to
 538                                         datagram transmission time as possible.*/
 539     u_int32_t num_records;           /* Number of tag-len-val flow/counter records to follow */
 540 } SFLSample_datagram_hdr;
 541
 542 #define SFL_MAX_DATAGRAM_SIZE 1500
 543 #define SFL_MIN_DATAGRAM_SIZE 200
 544 #define SFL_DEFAULT_DATAGRAM_SIZE 1400
 545
 546 #define SFL_DATA_PAD 400
 547
 548 #endif /* SFLOW_H */