Data.ByteString.Base32

This module contains ByteString-valued combinators for implementing the RFC 4648 specification of the Base32 encoding format. This includes padded and unpadded decoding variants, as well as internal and external validation for canonicity.

Encoding

encodeBase32 :: ByteString -> Text

Encode a ByteString value as a Base32 Text value with padding.

See: RFC-4648 section 6

Examples:

>>> encodeBase32 "Sun"
"KN2W4==="

encodeBase32' :: ByteString -> ByteString

Encode a ByteString value as a Base32 ByteString value with padding.

See: RFC-4648 section 6

Examples:

>>> encodeBase32' "Sun"
"KN2W4==="

encodeBase32Unpadded :: ByteString -> Text

Encode a ByteString value as a Base32 Text value without padding.

See: RFC-4648 section 6

Examples:

>>> encodeBase32Unpadded "Sun"
"KN2W4"

encodeBase32Unpadded' :: ByteString -> ByteString

Encode a ByteString value as a Base32 ByteString value without padding.

See: RFC-4648 section 6

Examples:

>>> encodeBase32Unpadded' "Sun"
"KN2W4"

Decoding

decodeBase32 :: ByteString -> Either Text ByteString

Decode an arbitrarily padded Base32-encoded ByteString value. If its length is not a multiple of 8, then padding characters will be added to fill out the input to a multiple of 8 for safe decoding, as Base32-encoded values are optionally padded.

See: RFC-4648 section 6

Examples:

>>> decodeBase32 "KN2W4==="
Right "Sun"

>>> decodeBase32 "KN2W4"
Right "Sun"

>>> decodeBase32 "KN2W==="
Left "Base32-encoded bytestring has invalid padding"

decodeBase32Unpadded :: ByteString -> Either Text ByteString

Decode an unpadded Base32-encoded ByteString value.

See: RFC-4648 section 6

Examples:

>>> decodeBase32Unpadded "KN2W4"
Right "Sun"

>>> decodeBase32Unpadded "KN2W4==="
Left "Base32-encoded bytestring has invalid padding"

decodeBase32Padded :: ByteString -> Either Text ByteString

Decode a padded Base32-encoded ByteString value.

See: RFC-4648 section 6

Examples:

>>> decodeBase32Padded "KN2W4==="
Right "Sun"

>>> decodeBase32Padded "KN2W4"
Left "Base32-encoded bytestring requires padding"

Validation

isBase32 :: ByteString -> Bool

Tell whether a ByteString value is encoded in padded or unpadded Base32 format

Examples:

>>> isBase32 "KN2W4"
True

>>> isBase32 "KN2W4==="
True

>>> isBase32 "KN2W4=="
False

isValidBase32 :: ByteString -> Bool

Tell whether a ByteString value is a valid Base32 format.

This will not tell you whether or not this is a correct Base32 representation, only that it conforms to the correct shape (including padding/size etc.). To check whether it is a true Base32 encoded ByteString value, use isBase32.

Examples:

>>> isValidBase32 "KN2W4"
True

>>> isValidBase32 "KN2W4="
False

>>> isValidBase32 "KN2W4%"
False