Add support for program loading flags - breaking change version

[Alan-Jowett]

Resolves: #3576

As requested by @shankarseal this is a breaking change (to keep the change simple) as the ebpf_extension_data_t wasn't following the correct contract for structures exposed to extensions.

Description

This pull request introduces several enhancements and new features to the eBPF program management system, primarily focusing on adding support for program flags and improving the handling of extension data. Below are the most significant changes grouped by theme:

Enhancements to Program Flags:

• Added functions to query and set BPF program flags in libbpf.h and libbpf_program.cpp, allowing for better control over program behavior. [1] [2]
• Updated ebpf_program_t structure to include a flags field in api_internal.h and ebpf_program.c, and added corresponding getter and setter functions. [1] [2] [3]
• Implemented the ebpf_program_set_flags function in ebpf_api.cpp to set flags on a program during initialization. [1] [2]
• Added new protocol operation EBPF_OPERATION_PROGRAM_SET_FLAGS to handle setting flags via IOCTL in ebpf_protocol.h and ebpf_core.c. [1] [2]

Enhancements to Extension Data:

• Expanded the ebpf_extension_data_t struct to include data_size and prog_attach_flags fields in ebpf_extension.h and updated related documentation. [1] [2]
• Modified ebpf_link.c to handle the new fields in ebpf_extension_data_t, ensuring proper initialization and usage during link creation and attachment. [1] [2] [3] [4] [5]
• Updated ebpf_windows.h to define new constants for version and size of ebpf_extension_data_t.

API and Export Updates:

• Added new exports bpf_program__flags and bpf_program__set_flags to ebpfapi/Source.def to expose the new flag functionalities. [1] [2]

Testing and Documentation:

• Updated helpers.h in end-to-end tests to include ebpf_windows.h and added methods to access client data in the _single_instance_hook class. [1] [2] [3]

These changes collectively enhance the flexibility and control over eBPF programs by introducing a robust mechanism for handling program-specific flags and improving the management of extension data.

Testing

CI/CD

Documentation

Yes.

Installation

No.

[dthaler]

Ok but see suggestions