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
allis a boolean. If set totrue, it returns a table containing all matching functions. Iffalse(default), it returns only the first matching value. The for loop is not necessary if the function target is only one (i.e.allis not set to true)
Returns a JSON object containing:
function_nameis the function namefunction_addressis the function addressfunction_total_bytesis 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
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