winpcap/Common/dagc.h

   1 /*
   2  * Copyright (c) 2003
   3  * NetGroup, Politecnico di Torino (Italy)
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  * notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  * notice, this list of conditions and the following disclaimer in the
  14  * documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the Politecnico di Torino nor the names of its
  16  * contributors may be used to endorse or promote products derived from
  17  * this software without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  20  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  21  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  22  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  23  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  24  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  25  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  26  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  27  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  28  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  29  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  30  *
  31  */
  32
  33 #define DAGC_ERRBUF_SIZE   512
  34 #define FILEBUFSIZE         65536
  35 #define MAXDAGCARDS         32
  36
  37 #ifndef _WIN32
  38
  39 typedef long long         long_long;
  40 typedef long long         ull_t;
  41 #define TRUE            1
  42 #define devicestring      "/dev/dag%d"
  43 #define dagc_sleepms(_MS)   usleep(_MS * 1000)
  44 #else /* _WIN32 */
  45
  46 typedef LONGLONG         long_long;
  47 typedef ULONGLONG         ull_t;
  48 #define dagc_sleepms(_MS)   Sleep(_MS)
  49 #define devicestring      "\\\\.\\dag%d"
  50
  51 #endif /* _WIN32 */
  52
  53 #define MIN_DAG_SNAPLEN      12
  54 #define MAX_DAG_SNAPLEN      2040
  55
  56 #define erffilestring      "erffile://"
  57
  58
  59 #define ATM_SNAPLEN         48
  60 /* Size of ATM payload */
  61 #define ATM_WLEN(h)         ATM_SNAPLEN
  62 #define ATM_SLEN(h)         ATM_SNAPLEN
  63
  64 /* Size Ethernet payload */
  65 #define ETHERNET_WLEN(h, b)   ((u_int)ntohs((h)->wlen) - ((b) >> 3))
  66 #define ETHERNET_SLEN(h, b)   min(ETHERNET_WLEN(h, b), \
  67                 (u_int)ntohs((h)->rlen) - dag_record_size - 2)
  68
  69 /* Size of HDLC payload */
  70 #define HDLC_WLEN(h, b)      ((u_int)ntohs((h)->wlen) - ((b) >> 3))
  71 #define HDLC_SLEN(h, b)      min(HDLC_WLEN(h, b), \
  72                 (u_int)ntohs((h)->rlen) - dag_record_size)
  73
  74 /* Flags for dagc_open */
  75 #define DAGC_OPEN_SHARED   1
  76 #define DAGC_OPEN_EXCLUSIVE 2
  77
  78 #define TYPE_LEGACY       0
  79 #define TYPE_HDLC_POS     1
  80 #define TYPE_ETH          2
  81 #define TYPE_ATM          3
  82 #define TYPE_AAL5         4
  83
  84 /*
  85  * Card statistics.
  86  */
  87 typedef struct dagc_stats_t
  88 {
  89     ull_t received;            /* (NOT IMPLEMENTED) total number of frames received by the DAG */
  90     ull_t dropped;            /* number of frames dropped for buffer full */
  91     ull_t captured;            /* (NOT IMPLEMENTED) number of frames that actually reach the
  92                                  application, i.e that are not filtered or dropped */
  93 } dagc_stats_t;
  94
  95 /*
  96  * Descriptor of an open session.
  97  * Note: the dagc_t descriptor is completely opaque to the application. It can be compared
  98  * to a file descriptor.
  99  */
 100 typedef struct dagc dagc_t;
 101
 102 /*
 103  * Card description.
 104  */
 105 typedef struct dagc_if_t
 106 {
 107    struct   dagc_if_t *next;
 108    char   *name;               /* pointer to a string to pass to dagc_open*/
 109    char   *description;         /* human-understandable description (e.g. Endace 3.5e Fast
 110                               Ethernet Card) */
 111 } dagc_if_t;
 112
 113
 114
 115 /*
 116  * returns a string with last dagc lib error
 117  */
 118 #define dagc_getlasterror(dagcfd) dagcfd->errbuf
 119
 120 /*
 121  * returns a linked list with the cards available on the systems. For every card, it scans the
 122  * card type and converts it to a human-understandable string, in order to provide a description
 123  * useful for example when a system has more than one card
 124  */
 125 int dagc_finddevs (dagc_if_t **alldevsp, char *ebuf);
 126
 127
 128 /*
 129  * frees the card list.
 130  */
 131 void dagc_freedevs (dagc_if_t *alldevsp);
 132
 133
 134 /*
 135  * Opens a card (or a file) for capture. Snaplen is the portion of packet delivered to the
 136  * application, flags can contain specific settings (for example promisc mode??), minbufsize
 137  * is the smallest buffer that the API can provide to the application (to limit CPU waste
 138  * with several small buffers under moderated network  throughputs)
 139  */
 140 dagc_t* dagc_open(const char *source, unsigned flags, char *ebuf);
 141
 142 /*
 143  * Sets the snaplen of a card
 144  * Returns -1 on failure. On success, the actual snaplen is returned (snap len has to be a multiple of 4
 145  * with DAG cards).
 146  */
 147 int dagc_setsnaplen(dagc_t *dagcfd, unsigned snaplen);
 148
 149 /*
 150  * closes a capture instance
 151  */
 152 void dagc_close(dagc_t *dagcfd);
 153
 154
 155 /*
 156  * returns the linktype of a card
 157  */
 158 int dagc_getlinktype(dagc_t *dagcfd);
 159
 160
 161 /*
 162  * returns the link speed of the adapter, in MB/s.
 163  * If the link speed of the card is unknown, -1 is returned.
 164  * XXX NOTE: Currently, there is no consistent way to get linkspeed querying the card.
 165  * As a consequence, we determine this value statically from the card model. For cards that can run at
 166  * different speeds, we report only the *maximum* speed.
 167  */
 168 int dagc_getlinkspeed(dagc_t *dagcfd);
 169
 170
 171 /*
 172  * Returns the length of the CRC checksum that the card associates with any packet in the hole. This
 173  * information will be used to understand the actual length of the packet on the wire.
 174  * Note: this information is not provided consistently by DAG cards, so we gather it from an environment
 175  * variable in Unix and from a registry key in Windows.
 176  */
 177 unsigned dagc_getfcslen(dagc_t *dagcfd);
 178
 179 /*
 180  * provides a buffer with the new packets (from the board or from the file) and its size.
 181  * On success, the return value is 0. If an error has occurred, the return value is -1.
 182  * If EOF has reached, the return value is -2. Note that this function always returns
 183  * immediately, eventually with an empty buffer, so it is possible to have a success (0)
 184  * return value and bufsize = 0.
 185  */
 186 int dagc_receive(dagc_t *dagcfd, u_char **buffer, u_int *bufsize);
 187
 188
 189 /*
 190  * returns nonzero if any data is available from dagcfd, -1 if an error occurred. Waits until almost the time
 191  * specified by timeout has past or any data is available. If timeout=0, returns immediately.
 192  * If timeout=NULL, blocks until a packet arrives.
 193  */
 194 int dagc_wait(dagc_t *dagcfd, struct timeval *timeout);
 195
 196
 197 /*
 198  * returns statistics about current capture session
 199  */
 200 int dagc_stats(dagc_t *dagcfd, dagc_stats_t *ps);
 201
 202
 203 /*
 204  * Opens a dump file to store the data of this capture.
 205  * Returns 0 on success.
 206  * NOTE: currently, dagc_dumpfile_open, dagc_dumpfile_close and dagc_dump are simply wrappers
 207  * for open, close and write. However, if the programmer uses these functions, he is more protected
 208  * against file format changes (for example if the file format will have an header in the future).
 209  * Moreover, assuming that the user knows the file format is a bad practice: providing
 210  * simple simple save functionality is more intutive and user-friendly.
 211  */
 212 int dagc_dumpfile_open(dagc_t *dagcfd, char* name);
 213
 214
 215 /*
 216  * Closes a dump file
 217  */
 218 int dagc_dumpfile_close(dagc_t *dagcfd);
 219
 220
 221 /*
 222  * Writes a buffer of packets to a dump file
 223  * Returns 0 on success.
 224  */
 225 int dagc_dump(dagc_t *dagcfd, u_char *buffer, u_int bufsize);