aujiz11/TOTP

TOTP for SA:MP/open.mp

See original version

This plugin allows you to generate one-time passwords based on time (and computing on algorithm based TOTP RFC 6238) are also used by Google in the Google Authenticator.

SA:MP uses the legacy plugin in plugins/. open.mp uses the native runtime component in components/. Both provide the same five Pawn natives below.

New generation/verification uses the server's 64-bit UTC clock, HMAC-SHA1, 30-second steps and strict Base32 secrets. Verification accepts skew from 0 to 2, counting adjacent steps on each side, the default is 1. The legacy native keeps its signed 32-bit UTC timestamp argument and permissive secret normalization. Its numeric result does not preserve leading zeros.

Verification is stateless: replay prevention and login rate limits remain the account service's responsibility.

Installation

Extract the ZIP into your server root, preserving paths. Keep libcrypto-3.dll (Windows) or libcrypto.so.3 (Linux) beside the server executable.

SA:MP

Use plugins/TOTP.dll on Windows or plugins/TOTP.so on Linux. Append TOTP (Windows) or TOTP.so (Linux) to the existing plugins line in server.cfg.

open.mp

Use the same binary as components/TOTP.dll on Windows or components/TOTP.so on Linux.

Include totp.inc from your pawno/include/ or qawno/include/. Existing Pawn scripts use the same native signatures on both servers.

Usage

GoogleAuthenticatorCode

native GoogleAuthenticatorCode(const secret[], timestamp);

Params

• secret: Base32 secret using legacy normalization, including lowercase and supported separators.
• timestamp: UTC Unix seconds in a signed 32-bit Pawn cell

Description

Returns a numeric six-digit code from 0 to 999999, or -1 on error. Leading zeros are lost in the numeric result. This legacy signature remains available for existing scripts.

TOTP_GenerateCode

native TOTP_GenerateCode(const secret[], code[], code_size);

Params

• secret: Strict uppercase Base32 secret, at most TOTP_MAX_SECRET_LENGTH (160) characters. Canonical terminal padding is accepted.
• code: Unpacked output array for the six-digit string and NUL terminator.
• code_size: Output capacity in cells, at least TOTP_CODE_SIZE (7).

Description

Generates the current code using server UTC time and preserves leading zeros. Returns TOTP_SUCCESS on success or TOTP_ERROR on invalid input, insufficient output capacity, clock or backend failure. Input and output arrays must not overlap.

TOTP_VerifyCode

native TOTP_VerifyCode(const secret[], const code[], skew = TOTP_DEFAULT_SKEW);

Params

• secret: Strict uppercase Base32 secret, with the same rules as TOTP_GenerateCode.
• code: Exactly six ASCII digits, including any leading zeros.
• skew: Adjacent 30-second steps accepted on each side. Defaults to TOTP_DEFAULT_SKEW (1), valid range is 0 through TOTP_MAX_SKEW (2).

Description

Returns TOTP_SUCCESS for a match, TOTP_MISMATCH for a well-formed code that does not match, or TOTP_ERROR for malformed input, invalid skew, clock or backend failure. With skew = 1, checks the previous, current and next step.

TOTP_GenerateSecret

native TOTP_GenerateSecret(secret[], secret_size);

Params

• secret: Unpacked output array for the generated Base32 secret.
• secret_size: Output capacity in cells, at least TOTP_SECRET_SIZE (33).

Description

Generates 160 random bits using the cryptographic backend and encodes them as 32 uppercase Base32 characters without padding. Returns TOTP_SUCCESS or TOTP_ERROR, random-generator failure produces no usable secret.

TOTP_GetVersion

native TOTP_GetVersion(version[], version_size);

Params

• version: Unpacked output array for the plugin's runtime version string.
• version_size: Output capacity in cells, at least TOTP_VERSION_SIZE (32).

Description

Writes the version displayed in the plugin's startup banner. Returns TOTP_SUCCESS or TOTP_ERROR. Version output is never truncated.

Build

Build from the repository root using CMake 3.25+, Ninja and a C++17 compiler.

git submodule update --init --recursive

Windows

cmake --preset windows-x86-release
cmake --build --preset windows-x86-release

Outputs: build/windows-x86-release/TOTP.dll

Linux

Install GCC multilib, 32-bit C/C++ development libraries, CMake, Ninja, Perl and the usual build tools. On Debian/Ubuntu, compiler dependencies include g++-multilib and libc6-dev-i386. The plugin requires a signed 64-bit time_t. CMake enables _TIME_BITS=64 and _FILE_OFFSET_BITS=64. For 32-bit glibc builds this needs glibc 2.34+. Post-2038 system time also requires kernel support for 64-bit time syscalls.

cmake --preset linux-x86-release
cmake --build --preset linux-x86-release

Outputs: build/linux-x86-release/TOTP.so