smgdc/README.md

smgdc

SourceMod gamedata checker.

Rewrite of a previous internal project. Faster. Stronger. More maintainable.

Usage

smgdc <specfile> --add-binary <binary> --add-binary <binary> ...

• specfile is a specification file or directory (tree) containing specification files.
• --add-binary specifies one or more binaries to add for checking.
  • This may be a os.pathsep-separated pair of values that map a physical file to one present in the specification file.

Specification file

A specification file is an INI configuration file used to check aspects of one or more binary (code) files.

Example:

; reports presence of a byte sequence in the Windows server binary, yielding signature
[CWeaponMedigun::SecondaryAttack()]
target = bin/tf/server.dll
type = bytesig
contents = 55 8B EC 56 8B 75 08 85 F6 0F 84 ?? ?? ?? ?? 53

; reports that a given immediate value in code is at a given location, yielding offsets, etc.
[CTFProjectile_Flare::Explode_Air()::SelfDamageRadius LINUX]
target = bin/tf/server_srv.so
type = value
symbol = _ZN19CTFProjectile_Flare11Explode_AirEP10CGameTraceib
offset = 0x468
struct = <f
assert = value == 100.0

; reports the presence of a symbol in a given vtable, yielding offset for Windows / Linux
[CBaseEntity::GetEnemy()]
target = bin/tf/server_srv.so
type = vfn
vtable = 11CBaseEntity
symbol = _ZN11CBaseEntity8GetEnemyEv

The entries specify a section name (must be unique within the file), a target binary's subpath to match against, a type of specification to check for, and additional information for a particular specification type.

This allows the validation process to be more flexible than a gameconf file is on its own, as that tells you nothing about the context (is the offset for a virtual file? a property?).

Types of specifications include:

• value: reads out a value from a binary
• bytesig: confirms the presence of a byte sequence
• vfn: takes a virtual method symbol and gets the vtable index for it on Linux and Windows (guesstimate on the latter)