epan/dissectors/packet-f5ethtrailer.h

   1 /* packet-f5ethtrailer.h
   2  *
   3  * F5 Ethernet Trailer Copyright 2008-2018 F5 Networks
   4  *
   5  * SPDX-License-Identifier: GPL-2.0-or-later
   6  */
   7
   8 /* How to use the fileinfo version tap
   9  *
  10  * Captures taken on an F5 device in versions 11.2.0 and later contain an
  11  * initial packet that has information about how the capture was taken and
  12  * about the device it was taken on (tcpdump command line, platform, version,
  13  * etc.).  This tap allows other dissectors to obtain the version of BIG-IP
  14  * software (if it is available).
  15  *
  16  * There are two functions defined in this header file (f5fileinfo_tap_reset()
  17  * and f5fileinfo_tap_pkt()).  These functions are registered with the tap and
  18  * will populate a structure provided by you with the version information.
  19  *
  20  * Step 1: Define a static variable of type "struct f5fileinfo".  This is where
  21  * the version information will be stored.
  22  *   static struct f5fileinfo myver = F5FILEINFO_TAP_DATA_INIT;
  23  *
  24  * Step 2: Register with the tap listener using the macro provided in your
  25  * proto_reg_handoff function:
  26  *   F5FILEINFO_TAP_LISTEN(&myver);
  27  *
  28  * Step 3: Use the version information in other parts of your code.
  29  *   if(myver.ver[0] == 11) {
  30  *      ...
  31  *   }
  32  *
  33  * If you need to do something additional when you run into a version, you can
  34  * define the F5FILEINFO_TAP_POST_FUNC macro before including this header file
  35  * to be the name of a fuction to call at the end of the tap function.  This
  36  * function must have a prototype of
  37  *   static void F5FILEINFO_TAP_POST_FUNC(struct f5fileinfo_tap_data *);
  38  * Note that this function also gets called with version of all zeroes when the
  39  * tap gets reset (reload file).
  40  * Note that this function does not get called if the version number does not
  41  * change.
  42  * Example:
  43  *   #define F5FILEINFO_TAP_POST_FUNC f5info_tap_local
  44  *   #include <epan/dissectors/packet-f5ethtrailer.h>
  45  *   ...
  46  *   static void f5info_tap_local(struct f5fileinfo_tap_data *tap_data)
  47  *   {
  48  *       ...
  49  *   }
  50  */
  51
  52 #ifndef _PACKETH_F5ETHTRAILER_H_
  53 #define _PACKETH_F5ETHTRAILER_H_
  54
  55 #define F5ETH_TAP_TMM_MAX   UINT16_MAX
  56 #define F5ETH_TAP_TMM_BITS  16
  57 #define F5ETH_TAP_SLOT_MAX  UINT16_MAX
  58 #define F5ETH_TAP_SLOT_BITS 16
  59
  60 /** Magic number for Ethernet trailer tap data to ensure that any tap and the dissector were both
  61  *  compiled from the same source.  No need to htonl this since the dissector and the tap should
  62  *  both be compiled on the same platform.
  63  *
  64  *  Increment this value when the struct f5eth_tap_data (below) is changed.
  65  */
  66 #define F5ETH_TAP_MAGIC     0x68744521
  67
  68 /** Data structure to hold data returned by the f5ethtrailer tap.  Magic has to be first. */
  69 typedef struct f5eth_tap_data {
  70     uint32_t magic;        /**< Verify proper version of dissector */
  71     uint32_t trailer_len;  /**< Overall length of the F5 trailer */
  72     /* 64 bit align */
  73     uint64_t flow;         /**< Flow ID */
  74     uint64_t peer_flow;    /**< Peer Flow ID */
  75     /* 64 bit align */
  76     char   *virtual_name; /**< Virtual server name */
  77     uint16_t slot;         /**< The slot the handled the packet (F5ETH_TAP_TMM_MAX == unknown) */
  78     uint16_t tmm;          /**< The tmm that handled the packet (F5ETH_TAP_sLOT_MAX == unknown) */
  79     uint8_t noise_low:1;  /**< If the frame has low noise(1) or not(0) */
  80     uint8_t noise_med:1;  /**< If the frame has medium noise(1) or not(0) */
  81     uint8_t noise_high:1; /**< If the frame has high noise(1) or not(0) */
  82     uint8_t flows_set:1;  /**< If the frame has flow/peerflow fields(1) or not(0) */
  83     uint8_t ingress:2;    /**< Whether the packet was ingress(1), egress(0) or unknown(3) */
  84 } f5eth_tap_data_t;
  85
  86 /** \brief Tap data version matches compiled version
  87  *
  88  *  @param tdata Pointer to tapdata from f5ethtrailer
  89  *  @return 1 if the version of the tapdata matches the compiled version of the tap. 0 otherwise.
  90  *
  91  *  Use this function to ensure that the data from the f5ethtrailer tap is the same as the
  92  *  structure used when your tap was compiled.  Use this to protect your tap from running against
  93  *  a newer/older version of the f5ethtrailer dissector.
  94  *
  95  *  For example, at the top of your tap packet function, you can use:
  96  *    if(check_f5eth_tap_magic(tdata) == 0) return 0;
  97  */
  98 inline static int check_f5eth_tap_magic(f5eth_tap_data_t *tdata)
  99 {
 100     return(tdata->magic == F5ETH_TAP_MAGIC ? 1 : 0);
 101 } /* check_f5eth_tap_magic() */
 102
 103 #define F5FILEINFO_TAP_MAGIC 0x46350001
 104
 105 /** Data structure to hold data returned by the f5fileinfo tap. */
 106 struct f5fileinfo_tap_data {
 107     uint32_t magic;  /**< Just to make sure that we have the same version. */
 108     uint32_t ver[6]; /**< Array for version and build elements. */
 109 };
 110
 111 #define F5FILEINFO_TAP_DATA_INIT { 0, { 0, 0, 0, 0, 0, 0 } }
 112
 113 #define F5VER_KNOWN(v) ((v)->ver[0] > 0)
 114
 115
 116 #define F5VER_GE_11_2(v) (((v)->ver[0] > 11) \
 117     || ((v)->ver[0] == 11 && (v)->ver[1] >= 2))
 118
 119 #define F5VER_GE_11_2_1(v) (((v)->ver[0] > 11) \
 120     || ((v)->ver[0] == 11 && (v)->ver[1] > 2) \
 121     || ((v)->ver[0] == 11 && (v)->ver[1] == 2 && (v)->ver[2] >= 1))
 122
 123 #define F5VER_GE_11_3(v) (((v)->ver[0] > 11) \
 124     || ((v)->ver[0] == 11 && (v)->ver[1] >= 3))
 125
 126 #define F5VER_GE_11_4(v) (((v)->ver[0] > 11) \
 127     || ((v)->ver[0] == 11 && (v)->ver[1] >= 4))
 128
 129 #define F5VER_GE_11_4_1(v) (((v)->ver[0] > 11) \
 130     || ((v)->ver[0] == 11 && (v)->ver[1] > 4) \
 131     || ((v)->ver[0] == 11 && (v)->ver[1] == 4 && (v)->ver[2] >= 1))
 132
 133 #define F5VER_GE_11_5(v) (((v)->ver[0] > 11) \
 134     || ((v)->ver[0] == 11 && (v)->ver[1] >= 5))
 135
 136 #define F5VER_GE_11_5_1(v) (((v)->ver[0] > 11) \
 137     || ((v)->ver[0] == 11 && (v)->ver[1] > 5) \
 138     || ((v)->ver[0] == 11 && (v)->ver[1] == 5 && (v)->ver[2] >= 1))
 139
 140 #define F5VER_GE_11_6(v) (((v)->ver[0] > 11) \
 141     || ((v)->ver[0] == 11 && (v)->ver[1] >= 6))
 142
 143 #define F5VER_GE_12_0(v) (((v)->ver[0] >= 12))
 144
 145
 146 #ifndef F5FILEINFOTAP_SRC
 147
 148 #ifdef F5FILEINFO_TAP_POST_FUNC
 149 static void F5FILEINFO_TAP_POST_FUNC(struct f5fileinfo_tap_data *);
 150 #endif
 151
 152 static void f5fileinfo_tap_reset(void *p)
 153 {
 154     struct f5fileinfo_tap_data *s;
 155
 156     s = (struct f5fileinfo_tap_data *)p;
 157     s->ver[0] = 0;
 158     s->ver[1] = 0;
 159     s->ver[2] = 0;
 160     s->ver[3] = 0;
 161     s->ver[4] = 0;
 162     s->ver[5] = 0;
 163 #   ifdef F5FILEINFO_TAP_POST_FUNC
 164         F5FILEINFO_TAP_POST_FUNC(s);
 165 #   endif
 166 } /* f5fileinfo_tap_reset() */
 167
 168 static tap_packet_status f5fileinfo_tap_pkt(
 169     void *tapdata,
 170     packet_info *pinfo _U_,
 171     epan_dissect_t *edt _U_,
 172     const void *data,
 173     tap_flags_t flags _U_
 174 ) {
 175     struct f5fileinfo_tap_data *s;
 176     struct f5fileinfo_tap_data *fromtap;
 177
 178     s = (struct f5fileinfo_tap_data *)tapdata;
 179     fromtap = (struct f5fileinfo_tap_data *)data;
 180     if(fromtap->magic != F5FILEINFO_TAP_MAGIC) {
 181         /* Magic numbers do not match.  f5ethtrailer plugin was compiled from
 182          * different source than this plugin. */
 183         return(TAP_PACKET_DONT_REDRAW);
 184     }
 185     if (s->ver[0] == fromtap->ver[0] &&
 186         s->ver[1] == fromtap->ver[1] &&
 187         s->ver[2] == fromtap->ver[2] &&
 188         s->ver[3] == fromtap->ver[3] &&
 189         s->ver[4] == fromtap->ver[4] &&
 190         s->ver[5] == fromtap->ver[5])
 191     {
 192         return(TAP_PACKET_DONT_REDRAW);
 193     }
 194     s->ver[0] = fromtap->ver[0];
 195     s->ver[1] = fromtap->ver[1];
 196     s->ver[2] = fromtap->ver[2];
 197     s->ver[3] = fromtap->ver[3];
 198     s->ver[4] = fromtap->ver[4];
 199     s->ver[5] = fromtap->ver[5];
 200 #   ifdef F5FILEINFO_TAP_POST_FUNC
 201         F5FILEINFO_TAP_POST_FUNC(s);
 202 #   endif
 203     return(TAP_PACKET_REDRAW);
 204 } /* f5fileinfo_tap_pkt() */
 205
 206
 207 #define F5FILEINFO_TAP_LISTEN(a) \
 208     register_tap_listener("f5fileinfo", (a), NULL, TL_REQUIRES_NOTHING, f5fileinfo_tap_reset, f5fileinfo_tap_pkt, NULL, NULL)
 209
 210
 211 #endif /* ifndef F5INFOTAP_SRC */
 212
 213
 214 #endif /* ifndef _PACKETH_F5ETHTRAILER_H_ */
 215
 216 /*
 217  * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
 218  *
 219  * Local variables:
 220  * c-basic-offset: 4
 221  * tab-width: 8
 222  * indent-tabs-mode: nil
 223  * End:
 224  *
 225  * vi: set shiftwidth=4 tabstop=8 expandtab:
 226  * :indentSize=4:tabSize=8:noTabs=true:
 227  */