Package 'secretbase'

Title: Cryptographic Hash, Extendable-Output and Base64 Functions
Description: Fast and memory-efficient streaming hash functions and base64 encoding / decoding. Hashes strings and raw vectors directly. Stream hashes files potentially larger than memory, as well as in-memory objects through R's serialization mechanism. Implementations include the SHA-256, SHA-3 and 'Keccak' cryptographic hash functions, SHAKE256 extendable-output function (XOF), and 'SipHash' pseudo-random function.
Authors: Charlie Gao [aut, cre] , Hibiki AI Limited [cph]
Maintainer: Charlie Gao <charlie.gao@shikokuchuo.net>
License: GPL (>= 3)
Version: 1.0.3
Built: 2024-11-18 05:54:13 UTC
Source: https://github.com/shikokuchuo/secretbase

Help Index


secretbase: Cryptographic Hash, Extendable-Output and Base64 Functions

Description

Fast and memory-efficient streaming hash functions and base64 encoding / decoding. Hashes strings and raw vectors directly. Stream hashes files potentially larger than memory, as well as in-memory objects through R's serialization mechanism. Implementations include the SHA-256, SHA-3 and 'Keccak' cryptographic hash functions, SHAKE256 extendable-output function (XOF), and 'SipHash' pseudo-random function.

Author(s)

Charlie Gao charlie.gao@shikokuchuo.net (ORCID)

See Also

Useful links:


Base64 Decode

Description

Decodes a character string, raw vector or other object from base64 encoding.

Usage

base64dec(x, convert = TRUE)

Arguments

x

an object.

convert

[default TRUE] logical TRUE to convert back to a character string, FALSE to convert back to a raw vector or NA to decode and then unserialize back to the original object.

Details

The value of ‘convert’ should be set to TRUE, FALSE or NA to be the reverse of the 3 encoding operations (for strings, raw vectors and arbitrary objects), in order to return the original object.

Value

A character string, raw vector, or other object depending on the value of ‘convert’. If conversion to a character string fails, a raw vector will be returned instead (accompanied by a warning).

References

This implementation is based that by 'The Mbed TLS Contributors' under the 'Mbed TLS' Trusted Firmware Project at https://www.trustedfirmware.org/projects/mbed-tls.

See Also

base64enc

Examples

base64dec(base64enc("secret base"))
base64dec(base64enc(as.raw(c(1L, 2L, 4L))), convert = FALSE)
base64dec(base64enc(data.frame()), convert = NA)

Base64 Encode

Description

Encodes a character string, raw vector or other object to base64 encoding.

Usage

base64enc(x, convert = TRUE)

Arguments

x

an object.

convert

[default TRUE] logical TRUE to encode to a character string or FALSE to a raw vector.

Details

A character string or raw vector (with no attributes) is encoded as is, whilst all other objects are first serialized (using R serialisation version 3, big-endian representation).

Value

A character string or raw vector depending on the value of ‘convert’.

References

This implementation is based that by 'The Mbed TLS Contributors' under the 'Mbed TLS' Trusted Firmware Project at https://www.trustedfirmware.org/projects/mbed-tls.

See Also

base64dec

Examples

base64enc("secret base")
base64enc(as.raw(c(1L, 2L, 4L)), convert = FALSE)
base64enc(data.frame())

Keccak Cryptographic Hash Algorithms

Description

Returns a Keccak hash of the supplied object or file.

Usage

keccak(x, bits = 256L, convert = TRUE, file)

Arguments

x

object to hash. A character string or raw vector (without attributes) is hashed ‘as is’. All other objects are stream hashed using R serialization (but without allocation of the serialized object).

bits

[default 256L] output size of the returned hash. Must be one of 224, 256, 384 or 512.

convert

[default TRUE] if TRUE, the hash is converted to its hex representation as a character string, if FALSE, output directly as a raw vector, or if NA, a vector of (32-bit) integer values.

file

character file name / path. If specified, ‘x’ is ignored. The file is stream hashed, thus capable of handling files larger than memory.

Value

A character string, raw or integer vector depending on ‘convert’.

R Serialization Stream Hashing

Where this is used, serialization is always version 3 big-endian represenation and the headers (containing R version and native encoding information) are skipped to ensure portability across platforms.

References

Keccak is the underlying algorithm for SHA-3, and is identical apart from the value of the padding parameter.

The Keccak algorithm was designed by G. Bertoni, J. Daemen, M. Peeters and G. Van Assche.

This implementation is based on one by 'The Mbed TLS Contributors' under the 'Mbed TLS' Trusted Firmware Project at https://www.trustedfirmware.org/projects/mbed-tls.

Examples

# Keccak-256 hash as character string:
keccak("secret base")

# Keccak-256 hash as raw vector:
keccak("secret base", convert = FALSE)

# Keccak-224 hash as character string:
keccak("secret base", bits = 224)

# Keccak-384 hash as character string:
keccak("secret base", bits = 384)

# Keccak-512 hash as character string:
keccak("secret base", bits = 512)

# Keccak-256 hash a file:
file <- tempfile(); cat("secret base", file = file)
keccak(file = file)
unlink(file)

SHA-256 Cryptographic Hash Algorithm

Description

Returns a SHA-256 hash of the supplied object or file, or HMAC if a secret key is supplied.

Usage

sha256(x, key = NULL, convert = TRUE, file)

Arguments

x

object to hash. A character string or raw vector (without attributes) is hashed ‘as is’. All other objects are stream hashed using R serialization (but without allocation of the serialized object).

key

[default NULL] If NULL, the SHA-256 hash of ‘x’ is returned. Alternatively, supply a character string or raw vector as a secret key to generate an HMAC. Note: for character vectors, only the first element is used.

convert

[default TRUE] if TRUE, the hash is converted to its hex representation as a character string, if FALSE, output directly as a raw vector, or if NA, a vector of (32-bit) integer values.

file

character file name / path. If specified, ‘x’ is ignored. The file is stream hashed, thus capable of handling files larger than memory.

Value

A character string, raw or integer vector depending on ‘convert’.

R Serialization Stream Hashing

Where this is used, serialization is always version 3 big-endian represenation and the headers (containing R version and native encoding information) are skipped to ensure portability across platforms.

References

The SHA-256 Secure Hash Standard was published by the National Institute of Standards and Technology (NIST) in 2002 at https://csrc.nist.gov/publications/fips/fips180-2/fips180-2.pdf.

This implementation is based on one by 'The Mbed TLS Contributors' under the 'Mbed TLS' Trusted Firmware Project at https://www.trustedfirmware.org/projects/mbed-tls.

Examples

# SHA-256 hash as character string:
sha256("secret base")

# SHA-256 hash as raw vector:
sha256("secret base", convert = FALSE)

# SHA-256 hash a file:
file <- tempfile(); cat("secret base", file = file)
sha256(file = file)
unlink(file)

# SHA-256 HMAC using a character string secret key:
sha256("secret", key = "base")

# SHA-256 HMAC using a raw vector secret key:
sha256("secret", key = charToRaw("base"))

SHA-3 Cryptographic Hash Algorithms

Description

Returns a SHA-3 hash of the supplied object or file.

Usage

sha3(x, bits = 256L, convert = TRUE, file)

Arguments

x

object to hash. A character string or raw vector (without attributes) is hashed ‘as is’. All other objects are stream hashed using R serialization (but without allocation of the serialized object).

bits

[default 256L] output size of the returned hash. Must be one of 224, 256, 384 or 512.

convert

[default TRUE] if TRUE, the hash is converted to its hex representation as a character string, if FALSE, output directly as a raw vector, or if NA, a vector of (32-bit) integer values.

file

character file name / path. If specified, ‘x’ is ignored. The file is stream hashed, thus capable of handling files larger than memory.

Value

A character string, raw or integer vector depending on ‘convert’.

R Serialization Stream Hashing

Where this is used, serialization is always version 3 big-endian represenation and the headers (containing R version and native encoding information) are skipped to ensure portability across platforms.

References

The SHA-3 Secure Hash Standard was published by the National Institute of Standards and Technology (NIST) in 2015 at doi:10.6028/NIST.FIPS.202.

This implementation is based on one by 'The Mbed TLS Contributors' under the 'Mbed TLS' Trusted Firmware Project at https://www.trustedfirmware.org/projects/mbed-tls.

Examples

# SHA3-256 hash as character string:
sha3("secret base")

# SHA3-256 hash as raw vector:
sha3("secret base", convert = FALSE)

# SHA3-224 hash as character string:
sha3("secret base", bits = 224)

# SHA3-384 hash as character string:
sha3("secret base", bits = 384)

# SHA3-512 hash as character string:
sha3("secret base", bits = 512)

# SHA3-256 hash a file:
file <- tempfile(); cat("secret base", file = file)
sha3(file = file)
unlink(file)

SHAKE256 Extendable Output Function

Description

Returns a SHAKE256 hash of the supplied object or file.

Usage

shake256(x, bits = 256L, convert = TRUE, file)

Arguments

x

object to hash. A character string or raw vector (without attributes) is hashed ‘as is’. All other objects are stream hashed using R serialization (but without allocation of the serialized object).

bits

[default 256L] output size of the returned hash. Must be between 8 and 2^24 and coercible to integer.

convert

[default TRUE] if TRUE, the hash is converted to its hex representation as a character string, if FALSE, output directly as a raw vector, or if NA, a vector of (32-bit) integer values.

file

character file name / path. If specified, ‘x’ is ignored. The file is stream hashed, thus capable of handling files larger than memory.

Details

To produce single integer values suitable for use as random seeds for R's pseudo random number generators (RNGs), set ‘bits’ to 32 and ‘convert’ to NA.

Value

A character string, raw or integer vector depending on ‘convert’.

R Serialization Stream Hashing

Where this is used, serialization is always version 3 big-endian represenation and the headers (containing R version and native encoding information) are skipped to ensure portability across platforms.

References

This implementation is based on one by 'The Mbed TLS Contributors' under the 'Mbed TLS' Trusted Firmware Project at https://www.trustedfirmware.org/projects/mbed-tls.

Examples

# SHAKE256 hash as character string:
shake256("secret base")

# SHAKE256 hash as raw vector:
shake256("secret base", convert = FALSE)

# SHAKE256 hash to integer:
shake256("secret base", bits = 32L, convert = NA)

# SHAKE256 hash a file:
file <- tempfile(); cat("secret base", file = file)
shake256(file = file)
unlink(file)

SipHash Pseudorandom Function

Description

Returns a fast, cryptographically-strong SipHash keyed hash of the supplied object or file. SipHash-1-3 is optimised for performance. Note: SipHash is not a cryptographic hash algorithm.

Usage

siphash13(x, key = NULL, convert = TRUE, file)

Arguments

x

object to hash. A character string or raw vector (without attributes) is hashed ‘as is’. All other objects are stream hashed using R serialization (but without allocation of the serialized object).

key

[default NULL] a character string or raw vector comprising the 16 byte (128 bit) key data, or else NULL which is equivalent to '0'. If a longer vector is supplied, only the first 16 bytes are used, and if shorter, padded with trailing '0'. Note: for character vectors, only the first element is used.

convert

[default TRUE] if TRUE, the hash is converted to its hex representation as a character string, if FALSE, output directly as a raw vector, or if NA, a vector of (32-bit) integer values.

file

character file name / path. If specified, ‘x’ is ignored. The file is stream hashed, thus capable of handling files larger than memory.

Value

A character string, raw or integer vector depending on ‘convert’.

R Serialization Stream Hashing

Where this is used, serialization is always version 3 big-endian represenation and the headers (containing R version and native encoding information) are skipped to ensure portability across platforms.

References

The SipHash family of cryptographically-strong pseudorandom functions (PRFs) are described in 'SipHash: a fast short-input PRF', Jean-Philippe Aumasson and Daniel J. Bernstein, Paper 2012/351, 2012, Cryptology ePrint Archive at https://ia.cr/2012/351.

This implementation is based on the SipHash streaming implementation by Daniele Nicolodi, David Rheinsberg and Tom Gundersen at https://github.com/c-util/c-siphash. This is in turn based on the SipHash reference implementation by Jean-Philippe Aumasson and Daniel J. Bernstein released to the public domain at https://github.com/veorq/SipHash.

Examples

# SipHash-1-3 hash as character string:
siphash13("secret base")

# SipHash-1-3 hash as raw vector:
siphash13("secret base", convert = FALSE)

# SipHash-1-3 hash using a character string key:
siphash13("secret", key = "base")

# SipHash-1-3 hash using a raw vector key:
siphash13("secret", key = charToRaw("base"))

# SipHash-1-3 hash a file:
file <- tempfile(); cat("secret base", file = file)
siphash13(file = file)
unlink(file)