Functions

Functions

Find and list functions in a binary by name, address, or pattern.

When to use

• Find a function by name or address
• List all functions matching a regex or byte pattern
• Get function metadata (address, size)
• Search for functions that match specific criteria (e.g., functions that call a certain API)

Instructions

Using the VulHunt MCP tools, open the project (open_project) and run the following Lua query (query_project), adapting it as needed:

local fs = project:functions(<target_function>)

-- Single result (FunctionContext)
if type(fs) ~= "table" then
  return {
      function_name = tostring(fs.name),
      function_address = tostring(fs.address),
      function_total_bytes = tostring(fs.total_bytes)
  }
end

-- Multiple results (FunctionContext[])
local results = {}
for _, f in ipairs(fs) do
  table.insert(results, {
      function_name = tostring(f.name),
      function_address = tostring(f.address),
      function_total_bytes = tostring(f.total_bytes)
    })
end

return results

Possible values for <target_function>:

• A string, e.g. "system"
• An AddressValue
  • VulHunt APIs return addresses as an AddressValue
  • To build an AddressValue, use for example: AddressValue.new(0x1234)
• A regex, e.g. {matching = "<regex>", kind = "symbol", all = true}
• A byte pattern, e.g. {matching = "41544155", kind = "bytes", all = true}

If no argument is passed to project:functions(), all functions are returned

all is a boolean. If set to true, it returns a table containing all matching functions. If false (default), it returns only the first matching value. The for loop is not necessary if the function target is only one (i.e. all is not set to true)

Returns a JSON object containing:

• function_name is the function name
• function_address is the function address
• function_total_bytes is the function length in bytes, calculated as the sum of the sizes of all its code blocks

It is also possible to get all functions satisfying certain criteria:

local function search_criteria(f)
      return f:named(<target_call>) and f:has_call(<target_call>)
    end

local fs = project:functions_where(search_criteria)

Possible values for <target_call>:

• A string, e.g. "system"
• An AddressValue
  • VulHunt APIs return addresses as AddressValue instances
  • Create one with AddressValue.new(<hex_addr>) (e.g., <hex_addr> = 0x1234)
• A regex, e.g. {matching = "<regex>", kind = "symbol"}
• A byte pattern, e.g. {matching = "41544155", kind = "bytes"}

References

• project-handle.md - All methods and fields for project
• function-context.md - All methods and fields for returned functions
• calls-to-query.md - Format for <target_call> parameter

URLs to additional documentation pages are available at https://vulhunt.re/llm.txt

Related Skills

• decompiler (/decompiler) - Decompile functions to understand their implementation and logic
• call-sites (/call-sites) - Find where functions are called and analyze their usage patterns
• byte-pattern-matching (/byte-pattern-matching) - Alternative method to find functions by searching for specific instruction sequences
• dataflow-analysis (/dataflow-analysis) - Track data flow within functions to detect vulnerabilities