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Diffstat (limited to 'contrib/libpcap/README.dag')
| -rw-r--r-- | contrib/libpcap/README.dag | 51 |
1 files changed, 48 insertions, 3 deletions
diff --git a/contrib/libpcap/README.dag b/contrib/libpcap/README.dag index eb1471b..49b3e73 100644 --- a/contrib/libpcap/README.dag +++ b/contrib/libpcap/README.dag @@ -37,12 +37,57 @@ cards and will not capture from the native OS packet stream. ---------------------------------------------------------------------- +Libpcap when built for DAG cards against dag-2.5.1 or later releases: + +Timeouts are supported. pcap_dispatch() will return after to_ms milliseconds +regardless of how many packets are received. If to_ms is zero pcap_dispatch() +will block waiting for data indefinitely. + +pcap_dispatch() will block on and process a minimum of 64kB of data (before +filtering) for efficiency. This can introduce high latencies on quiet +interfaces unless a timeout value is set. The timeout expiring will override +the 64kB minimum causing pcap_dispatch() to process any available data and +return. + +pcap_setnonblock is supported. When nonblock is set, pcap_dispatch() will +check once for available data, process any data available up to count, then +return immediately. + +pcap_findalldevs() is supported, e.g. dag0, dag1... + +Some DAG cards can provide more than one 'stream' of received data. +This can be data from different physical ports, or separated by filtering +or load balancing mechanisms. Receive streams have even numbers, e.g. +dag0:0, dag0:2 etc. Specifying transmit streams for capture is not supported. + +pcap_setfilter() is supported, BPF programs run in userspace. + +pcap_setdirection() is not supported. Only received traffic is captured. +DAG cards normally do not have IP or link layer addresses assigned as +they are used to passively monitor links. + +pcap_breakloop() is supported. + +pcap_datalink() and pcap_list_datalinks() are supported. The DAG card does +not attempt to set the correct datalink type automatically where more than +one type is possible. + +pcap_stats() is supported. ps_drop is the number of packets dropped due to +RX stream buffer overflow, this count is before filters are applied (it will +include packets that would have been dropped by the filter). The RX stream +buffer size is user configurable outside libpcap, typically 16-512MB. + +pcap_get_selectable_fd() is not supported, DAG cards do not support +poll/select methods. + +pcap_inject() and pcap_sendpacket() are not supported. + +---------------------------------------------------------------------- + Please submit bug reports via <support@endace.com>. -Please also visit our Web pages at: +Please also visit our Web site at: http://www.endace.com/ - http://dag.cs.waikato.ac.nz/ For more information about Endace DAG cards contact <sales@endace.com>. - |
