Base32 Class Reference

RFC 4648 base32 codec, used for TOTP shared secrets. More...

#include <base32.h>

Static Public Member Functions
static auto	decode (const QByteArray &encodedData) -> QByteArray
	Decode strict RFC 4648 base32 data.
static auto	encode (const QByteArray &data) -> QByteArray
	Encode raw bytes as padded RFC 4648 base32.
static auto	addPadding (const QByteArray &encodedData) -> QByteArray
	Append '=' padding up to a multiple of 8 characters.
static auto	removePadding (const QByteArray &encodedData) -> QByteArray
	Strip trailing '=' padding.
static auto	sanitizeInput (const QByteArray &encodedData) -> QByteArray
	Make human-entered base32 text decodable.

Private Member Functions
	Base32 ()=default
	Static-only class; never instantiated.

Detailed Description

RFC 4648 base32 codec, used for TOTP shared secrets.

Ported from KeePassXC (src/core/Base32.cpp). decode() is deliberately strict: the input length must be a multiple of 8 and every character must be in the base32 alphabet, so whitespace is an error rather than something to skip. Secrets that come from a human (or from a QR code label) therefore go through sanitizeInput() first, making the canonical entry point:

const QByteArray secret =
Base32::decode(Base32::sanitizeInput(text.toLatin1()));

Failure is reported as an empty QByteArray. A successful decode of a non-empty input always yields at least one byte, so isEmpty() is an unambiguous error test.

Definition at line 34 of file base32.h.

Member Function Documentation

addPadding()

auto Base32::addPadding ( const QByteArray & encodedData ) -> QByteArray

staticnodiscard

Append '=' padding up to a multiple of 8 characters.

Parameters

encodedData

Unpadded or partially padded base32 text.

Returns

Padded text, or encodedData unchanged when its length remainder is impossible for base32 (1, 3 or 6).

Definition at line 275 of file base32.cpp.

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decode()

auto Base32::decode ( const QByteArray & encodedData ) -> QByteArray

staticnodiscard

Decode strict RFC 4648 base32 data.

Parameters

encodedData

Padded base32 text whose length is a multiple of 8.

Returns

Decoded bytes, or an empty QByteArray when the input is empty, mis-padded, or contains a character outside "A-Za-z2-7=".

Definition at line 128 of file base32.cpp.

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encode()

auto Base32::encode ( const QByteArray & data ) -> QByteArray

staticnodiscard

Encode raw bytes as padded RFC 4648 base32.

Parameters

data	Raw bytes to encode.

Returns

Upper-case padded base32 text, or an empty QByteArray when data is empty.

Definition at line 191 of file base32.cpp.

removePadding()

auto Base32::removePadding ( const QByteArray & encodedData ) -> QByteArray

staticnodiscard

Strip trailing '=' padding.

Parameters

encodedData

Padded base32 text.

Returns

Text without padding, or encodedData unchanged when its length is not a multiple of 8.

Definition at line 294 of file base32.cpp.

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sanitizeInput()

auto Base32::sanitizeInput ( const QByteArray & encodedData ) -> QByteArray

staticnodiscard

Make human-entered base32 text decodable.

Drops every character outside "A-Za-z2-7" (so the spaces and dashes used to group a printed secret are tolerated), maps the digits that are ambiguous in the base32 alphabet (0 to O, 1 to L, 8 to B), then pads the result with addPadding().

Parameters

encodedData

Raw user input.

Returns

Sanitized, padded base32 text.

Definition at line 305 of file base32.cpp.

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The documentation for this class was generated from the following files:

• src/base32.h
• src/base32.cpp