Collect SEC BPF information

[pombredanne]

It would be useful to parse SEC() definitions for BPF programs in C source code as used in the Linux kernel and programs running in the kernel.

SEC sections in C source code such as https://github.com/torvalds/linux/blob/3a8a670eeeaa40d87bd38a587438952741980c18/samples/bpf/tracex7_kern.c#L6C1-L6C25 contain structured data that are further ending in a compiled ELF section and in compiled "BPF" code (in the .BTF section.)

Some examples include "license", "version" and related information similar to what we can collect using MODULE_XXX macros or their output inlined in compiled kernel ELFs (See for instance simple regexes in https://github.com/nexB/scancode-plugins/blob/4df0cf04e1b7b6774ba6e983c7c57002f19327c9/binary-analysis/scancode-compiledcode/src/compiledcode/sourcecode/kernel.py )

There should be some example in this package:

$ rpm -qfi /usr/lib64/bpf/xdpdump_xdp.o
Name        : xdp-tools
Version     : 1.2.3
Release     : 1.fc36
Architecture: x86_64
Install Date: Thu 29 Sep 2022 11:34:49 AM CEST
Group       : Unspecified
Size        : 634410
License     : GPLv2
Signature   : RSA/SHA256, Thu 17 Feb 2022 04:29:22 PM CET, Key ID 999f7cbf38ab71f4
Source RPM  : xdp-tools-1.2.3-1.fc36.src.rpm
Build Date  : Thu 17 Feb 2022 04:27:35 PM CET
Build Host  : buildhw-x86-08.iad2.fedoraproject.org
Packager    : Fedora Project
Vendor      : Fedora Project
URL         : https://github.com/xdp-project/xdp-tools
Bug URL     : https://bugz.fedoraproject.org/xdp-tools
Summary     : Utilities and example programs for use with XDP
Description :
Utilities and example programs for use with XDP

and

$ readelf -WS bpf/xdpdump_xdp.o
There are 14 section headers, starting at offset 0xc30:

Section Headers:
  [Nr] Name              Type            Address          Off    Size   ES Flg Lk Inf Al
  [ 0]                   NULL            0000000000000000 000000 000000 00      0   0  0
  [ 1] .text             PROGBITS        0000000000000000 000040 000000 00  AX  0   0  4
  [ 2] xdpdump_xdp       PROGBITS        0000000000000000 000040 000118 00  AX  0   0  8
  [ 3] .relxdpdump_xdp   REL             0000000000000000 000a10 000020 10   I 11   2  8
  [ 4] .data             PROGBITS        0000000000000000 000158 00000c 00  WA  0   0  4
  [ 5] .maps             PROGBITS        0000000000000000 000168 000020 00  WA  0   0  8
  [ 6] license           PROGBITS        0000000000000000 000188 000004 00  WA  0   0  1
  [ 7] .BTF              PROGBITS        0000000000000000 00018c 0005df 00      0   0  1
  [ 8] .rel.BTF          REL             0000000000000000 000a30 000030 10   I 11   7  8
  [ 9] .BTF.ext          PROGBITS        0000000000000000 00076b 0001a0 00      0   0  1
  [10] .rel.BTF.ext      REL             0000000000000000 000a60 000170 10   I 11   9  8
  [11] .symtab           SYMTAB          0000000000000000 000910 0000c0 18     12   4  8
  [12] .strtab           STRTAB          0000000000000000 0009d0 00003b 00      0   0  1
  [13] .shstrtab         STRTAB          0000000000000000 000bd0 00005b 00      0   0  1
Key to Flags:
  W (write), A (alloc), X (execute), M (merge), S (strings), I (info),
  L (link order), O (extra OS processing required), G (group), T (TLS),
  C (compressed), x (unknown), o (OS specific), E (exclude),
  D (mbind), p (processor specific)

and the SEC calls in the corresponding source code https://github.com/search?q=repo%3Axdp-project%2Fxdp-tools+"SEC("&type=code

This issue is to collect the source code side of the SEC sections