protocol

paseto_protocol

PASETO v4.local and v4.public protocol for byte payloads.

Availability:
logtalk_load(paseto(loader))
Author: Paulo Moura
Version: 1:0:0
Date: 2026-08-08
Compilation flags:
static
Dependencies:
(none)
Remarks:
(none)
Inherited public predicates:
(none)

Public predicates

local_key/1

Generates a 32-byte v4.local key.

Compilation flags:
static
Template:
local_key(Key)
Mode and number of proofs:
local_key(-list(byte)) - one

public_keypair/2

Generates an Ed25519 seed and public key for v4.public tokens.

Compilation flags:
static
Template:
public_keypair(Seed,PublicKey)
Mode and number of proofs:
public_keypair(-list(byte),-list(byte)) - one

local_encrypt/3

Encrypts Payload using a 32-byte local Key and empty footer and implicit assertion.

Compilation flags:
static
Template:
local_encrypt(Key,Payload,Token)
Mode and number of proofs:
local_encrypt(+list(byte),+list(byte),-atom) - one_or_error
Exceptions:
Key is a variable or a partial list:
instantiation_error
Key is not a list of the required number of bytes:
type_error(list(byte,32),Key)
Key contains a non-integer byte:
type_error(integer,Byte)
Key contains an integer outside the byte range:
domain_error(byte,Byte)
Payload is a variable or a partial list:
instantiation_error
Payload is not a list of the required number of bytes:
type_error(list(byte,32),Payload)
Payload contains a non-integer byte:
type_error(integer,Byte)
Payload contains an integer outside the byte range:
domain_error(byte,Byte)

local_encrypt/5

Encrypts Payload using a 32-byte local Key and authenticates Footer and ImplicitAssertion.

Compilation flags:
static
Template:
local_encrypt(Key,Payload,Footer,ImplicitAssertion,Token)
Mode and number of proofs:
local_encrypt(+list(byte),+list(byte),+list(byte),+list(byte),-atom) - one_or_error
Exceptions:
Key is a variable or a partial list:
instantiation_error
Key is not a list of the required number of bytes:
type_error(list(byte,32),Key)
Key contains a non-integer byte:
type_error(integer,Byte)
Key contains an integer outside the byte range:
domain_error(byte,Byte)
Payload is a variable or a partial list:
instantiation_error
Payload is not a list of the required number of bytes:
type_error(list(byte,32),Payload)
Payload contains a non-integer byte:
type_error(integer,Byte)
Payload contains an integer outside the byte range:
domain_error(byte,Byte)
Footer is a variable or a partial list:
instantiation_error
Footer is not a list of the required number of bytes:
type_error(list(byte,32),Footer)
Footer contains a non-integer byte:
type_error(integer,Byte)
Footer contains an integer outside the byte range:
domain_error(byte,Byte)
ImplicitAssertion is a variable or a partial list:
instantiation_error
ImplicitAssertion is not a list of the required number of bytes:
type_error(list(byte,32),ImplicitAssertion)
ImplicitAssertion contains a non-integer byte:
type_error(integer,Byte)
ImplicitAssertion contains an integer outside the byte range:
domain_error(byte,Byte)

local_decrypt/3

Authenticates and decrypts a local Token using an empty implicit assertion.

Compilation flags:
static
Template:
local_decrypt(Token,Key,Payload)
Mode and number of proofs:
local_decrypt(+atom,+list(byte),-list(byte)) - zero_or_one_or_error
Exceptions:
Token is a variable:
instantiation_error
Token is neither a variable nor an atom:
type_error(atom,Token)
Token is an atom but not a canonical v4.local token:
domain_error(paseto_v4_token,Token)
Key is a variable or a partial list:
instantiation_error
Key is not a list of the required number of bytes:
type_error(list(byte,32),Key)
Key contains a non-integer byte:
type_error(integer,Byte)
Key contains an integer outside the byte range:
domain_error(byte,Byte)

local_decrypt/5

Authenticates and decrypts a local Token using ImplicitAssertion and returns its authenticated Footer.

Compilation flags:
static
Template:
local_decrypt(Token,Key,ImplicitAssertion,Payload,Footer)
Mode and number of proofs:
local_decrypt(+atom,+list(byte),+list(byte),-list(byte),-list(byte)) - zero_or_one_or_error
Exceptions:
Token is a variable:
instantiation_error
Token is neither a variable nor an atom:
type_error(atom,Token)
Token is an atom but not a canonical v4.local token:
domain_error(paseto_v4_token,Token)
Token is a v4.local token but has a malformed compact serialization:
domain_error(paseto_compact_serialization,malformed)
Token contains non-canonical base64url data:
representation_error(base64)
Token has a malformed local payload:
domain_error(paseto_v4_local_payload,Token)
Key is a variable or a partial list:
instantiation_error
Key is not a list of the required number of bytes:
type_error(list(byte,32),Key)
Key contains a non-integer byte:
type_error(integer,Byte)
Key contains an integer outside the byte range:
domain_error(byte,Byte)
ImplicitAssertion is a variable or a partial list:
instantiation_error
ImplicitAssertion is not a list of the required number of bytes:
type_error(list(byte,32),ImplicitAssertion)
ImplicitAssertion contains a non-integer byte:
type_error(integer,Byte)
ImplicitAssertion contains an integer outside the byte range:
domain_error(byte,Byte)

public_sign/3

Signs Payload using an Ed25519 Seed and empty footer and implicit assertion.

Compilation flags:
static
Template:
public_sign(Seed,Payload,Token)
Mode and number of proofs:
public_sign(+list(byte),+list(byte),-atom) - one_or_error
Exceptions:
Seed is a variable or a partial list:
instantiation_error
Seed is not a list of the required number of bytes:
type_error(list(byte,32),Seed)
Seed contains a non-integer byte:
type_error(integer,Byte)
Seed contains an integer outside the byte range:
domain_error(byte,Byte)
Payload is a variable or a partial list:
instantiation_error
Payload is not a list of the required number of bytes:
type_error(list(byte,32),Payload)
Payload contains a non-integer byte:
type_error(integer,Byte)
Payload contains an integer outside the byte range:
domain_error(byte,Byte)

public_sign/5

Signs Payload using an Ed25519 Seed and authenticates Footer and ImplicitAssertion.

Compilation flags:
static
Template:
public_sign(Seed,Payload,Footer,ImplicitAssertion,Token)
Mode and number of proofs:
public_sign(+list(byte),+list(byte),+list(byte),+list(byte),-atom) - one_or_error
Exceptions:
Seed is a variable or a partial list:
instantiation_error
Seed is not a list of the required number of bytes:
type_error(list(byte,32),Seed)
Seed contains a non-integer byte:
type_error(integer,Byte)
Seed contains an integer outside the byte range:
domain_error(byte,Byte)
Payload is a variable or a partial list:
instantiation_error
Payload is not a list of the required number of bytes:
type_error(list(byte,32),Payload)
Payload contains a non-integer byte:
type_error(integer,Byte)
Payload contains an integer outside the byte range:
domain_error(byte,Byte)
Footer is a variable or a partial list:
instantiation_error
Footer is not a list of the required number of bytes:
type_error(list(byte,32),Footer)
Footer contains a non-integer byte:
type_error(integer,Byte)
Footer contains an integer outside the byte range:
domain_error(byte,Byte)
ImplicitAssertion is a variable or a partial list:
instantiation_error
ImplicitAssertion is not a list of the required number of bytes:
type_error(list(byte,32),ImplicitAssertion)
ImplicitAssertion contains a non-integer byte:
type_error(integer,Byte)
ImplicitAssertion contains an integer outside the byte range:
domain_error(byte,Byte)

public_verify/3

Authenticates a public Token using an Ed25519 public key and empty implicit assertion.

Compilation flags:
static
Template:
public_verify(Token,PublicKey,Payload)
Mode and number of proofs:
public_verify(+atom,+list(byte),-list(byte)) - zero_or_one_or_error
Exceptions:
Token is a variable:
instantiation_error
Token is neither a variable nor an atom:
type_error(atom,Token)
Token is an atom but not a canonical v4.public token:
domain_error(paseto_v4_token,Token)
PublicKey is a variable or a partial list:
instantiation_error
PublicKey is not a list of the required number of bytes:
type_error(list(byte,32),PublicKey)
PublicKey contains a non-integer byte:
type_error(integer,Byte)
PublicKey contains an integer outside the byte range:
domain_error(byte,Byte)

public_verify/5

Authenticates a public Token using an Ed25519 public key and ImplicitAssertion and returns its authenticated Footer.

Compilation flags:
static
Template:
public_verify(Token,PublicKey,ImplicitAssertion,Payload,Footer)
Mode and number of proofs:
public_verify(+atom,+list(byte),+list(byte),-list(byte),-list(byte)) - zero_or_one_or_error
Exceptions:
Token is a variable:
instantiation_error
Token is neither a variable nor an atom:
type_error(atom,Token)
Token is an atom but not a canonical v4 token:
domain_error(paseto_v4_token,Token)
Token is a canonical v4 token but has a malformed compact serialization:
domain_error(paseto_compact_serialization,malformed)
Token contains non-canonical base64url data:
representation_error(base64)
Token has a malformed public payload:
domain_error(paseto_v4_public_payload,Token)
PublicKey is a variable or a partial list:
instantiation_error
PublicKey is not a list of the required number of bytes:
type_error(list(byte,32),PublicKey)
PublicKey contains a non-integer byte:
type_error(integer,Byte)
PublicKey contains an integer outside the byte range:
domain_error(byte,Byte)
ImplicitAssertion is a variable or a partial list:
instantiation_error
ImplicitAssertion is not a list of the required number of bytes:
type_error(list(byte,32),ImplicitAssertion)
ImplicitAssertion contains a non-integer byte:
type_error(integer,Byte)
ImplicitAssertion contains an integer outside the byte range:
domain_error(byte,Byte)

Protected predicates

(none)

Private predicates

(none)

Operators

(none)