get-vtable-from-yaml

name	get-vtable-from-yaml
description	Load vtable information from a pre-generated YAML file. Use this skill when you need to get vtable address and size for a class before analyzing virtual functions. This skill checks for existing vtable YAML files and errors out if not found, ensuring the vtable analysis has been done first.

Get VTable from YAML

Load vtable information from a pre-generated {class_name}_vtable.{platform}.yaml file beside the binary.

Parameters

• class_name: The class name to look up (e.g., CCSPlayerController, CCSPlayer_WeaponServices, CServerSideClient)

Method

1. Check and Load VTable YAML

Run the following code with the appropriate class_name:

mcp__ida-pro-mcp__py_eval code="""
import idaapi
import os

class_name = "<CLASS_NAME>"  # Replace with actual class name

input_file = idaapi.get_input_file_path()
dir_path = os.path.dirname(input_file)
platform = 'windows' if input_file.endswith('.dll') else 'linux'

yaml_path = os.path.join(dir_path, f"{class_name}_vtable.{platform}.yaml")

if os.path.exists(yaml_path):
    with open(yaml_path, 'r', encoding='utf-8') as f:
        print(f.read())
    print(f"YAML_EXISTS: True")
else:
    print(f"ERROR: Required file {class_name}_vtable.{platform}.yaml not found.")
"""

2. Handle Result

If YAML exists (YAML_EXISTS: True), extract these values from the output:

• vtable_va: The vtable virtual address (use as <VTABLE_START>)
• vtable_rva: The vtable relative virtual address
• vtable_size: The vtable size in bytes
• vtable_numvfunc: The valid vtable entry count (last valid index = count - 1)
• vtable_entries: An array of virtual functions starting from vtable[0].

Example YAML content:

vtable_class: CCSPlayerController
vtable_symbol: _ZTV19CCSPlayerController
vtable_va: 0x221fc80
vtable_rva: 0x221fc80
vtable_size: 0xd60
vtable_numvfunc: 428
vtable_entries:
  - 0x9b4bb0
  - 0x9b4bc0
  - 0x9b4bd0

If YAML does NOT exist, ERROR OUT and report to user:

ERROR: Required file {class_name}_vtable.{platform}.yaml not found.
Please run `/write-vtable-as-yaml` with class_name={class_name} first to generate the vtable YAML file.

Do NOT proceed with any remaining steps in the calling skill.

Usage in Other Skills

When a skill needs vtable information, use this skill first:

### 1. Get {ClassName} VTable Address

**ALWAYS** Use SKILL `/get-vtable-from-yaml` with `class_name={ClassName}`.

If the skill returns an error, stop and report to user.
Otherwise, extract `vtable_va`, `vtable_numvfunc` and `vtable_entries` for subsequent steps.

Expected Output Values

Field	Description	Example
vtable_class	Class name	CCSPlayerController
vtable_va	Virtual address of vtable	0x2114cd0
vtable_rva	Relative virtual address	0x2114cd0
vtable_size	Size in bytes	0xd60
vtable_numvfunc	Number of virtual functions	428
vtable_entries	An array of virtual functions starting from vtable[0]	...