tcpdump mailing list archives
[RFC LIBPCAP PATCH 0/1] LINKTYPE_LINUX_SLL2 implementation
From: Petr Vorel <pvorel () suse cz>
Date: Thu, 12 Jul 2018 20:02:18 +0200
Hi, this is an attempt to implement LINKTYPE_LINUX_SLL2 [1]. The main adventure over LINKTYPE_LINUX_SLL [2] is having "Interface index" field, which allows to show interface name for "any" device. This part is required for following patch in tcpdump, here I describe libpcap part. Unfortunately I haven't found a way how to coexist in runtime library both LINKTYPE_LINUX_SLL and LINKTYPE_LINUX_SLL2, so by default LINKTYPE_LINUX_SLL2 is enabled (PCAP_SUPPORT_SLL_V2 definition). For users which needs, who needs to have LINKTYPE_LINUX_SLL, they have to compile libpcap with --enable-sll-v2 option. The reason for this is that it's look like there is no way to pass dlt info to functions activate_new(pcap_t *handle), pcap_create_interface(const char *device, char *ebuf), ... Maybe I'm missing something obvious and there can be both LINKTYPE_LINUX_SLL and LINKTYPE_LINUX_SLL2 compiled in the library. It's also a bit easier to reuse sll_header for LINKTYPE_LINUX_SLL2. Solution allowing both linktypes would require to create sll2_header. Implementation isn't perfect, maybe some places in pcap-linux.c related to cooked mode (cooked_ok) needs to chose use DLT_LINUX_SLL2 for LINKTYPE_LINUX_SLL2 (I kept it DLT_LINUX_SLL only as CAN bus and CAN FD aren't mentioned in LINKTYPE_LINUX_SLL2 spec [1]). But this part needs Comments and suggestions are welcome. Kind regards, Petr [1] http://www.tcpdump.org/linktypes/LINKTYPE_LINUX_SLL2.html [2] http://www.tcpdump.org/linktypes/LINKTYPE_LINUX_SLL.html Petr Vorel (1): Implement DLT_LINUX_SLL2 INSTALL.md | 2 +- cmakeconfig.h.in | 3 +++ config.h.in | 4 ++++ configure | 20 ++++++++++++++++++++ configure.ac | 10 ++++++++++ gencode.c | 3 +++ pcap-common.c | 1 + pcap-linux.c | 12 ++++++++++++ pcap.c | 4 ++++ pcap/sll.h | 21 +++++++++++++++++++-- 10 files changed, 77 insertions(+), 3 deletions(-) -- 2.18.0 _______________________________________________ tcpdump-workers mailing list tcpdump-workers () lists tcpdump org https://lists.sandelman.ca/mailman/listinfo/tcpdump-workers
Current thread:
- [RFC LIBPCAP PATCH 0/1] LINKTYPE_LINUX_SLL2 implementation Petr Vorel (Jul 12)
- [RFC LIBPCAP PATCH 1/1] Implement DLT_LINUX_SLL2 Petr Vorel (Jul 12)
- Re: [RFC LIBPCAP PATCH 0/1] LINKTYPE_LINUX_SLL2 implementation Petr Vorel (Jul 12)
- Re: [RFC LIBPCAP PATCH 0/1] LINKTYPE_LINUX_SLL2 implementation Guy Harris (Jul 12)
- Re: [RFC LIBPCAP PATCH 0/1] LINKTYPE_LINUX_SLL2 implementation Petr Vorel (Jul 12)
- Re: [RFC LIBPCAP PATCH 0/1] LINKTYPE_LINUX_SLL2 implementation Denis Ovsienko (Jul 12)