X509.RDNSequence (X509 v0.8.3) View Source

Convenience functions for creating :rdnSquence tuples, as defined in Erlang's :public_key module as the issuer_name() type, and representing the X.509 RDNSequence type. RDNSequences are primarily used for the Subject and Issuer fields of certificates, as well as the Subject field of CSRs.

Note that this module implements a commonly used subset of RDNSequence values. It supports only a single attribute type/value pair for each element in the sequence, and it implements the attribute types specified in RFC5280, section 4.1.2.4, with a few extensions from LDAP:

countryName (C)
organizationName (O)
organizationalUnitName (OU)
dnQualifier
stateOrProvinceName (ST)
commonName (CN)
serialNumber
localityName (L)
title
name
surname (SN)
givenName (GN)
initials
pseudonym
generationQualifier
domainComponent (DC)
emailAddress (E)

This module encodes values as UTF8String where possible, or else PrintableString/IA5String where required.

Link to this section Summary

Types

attr()

RDN type/value pair.

attr_list()

List of RDN type/value pairs

t()

RDN sequence for use in OTP certificate and CSR records

Functions

get_attr(arg, attr_type)

Extracts the values for the specified attributes from a :rdnSquence tuple.

new(rdn, type \\ :plain)

Creates a new :rdnSquence tuple.

to_string(arg)

Converts an :rdnSquence tuple to a human readable string, in hierarchical format.

Link to this section Types

attr()

Specs

attr() :: {binary() | atom(), binary()} | {:public_key.oid() | term()}

RDN type/value pair.

The first element must be a string (short or long form) or atom (long form) matching one of the supported attribute types. The second element is the associated string value, which will be encoded as appropriate for the attribute type.

Alternatively, the attribute_type can be specified as an OID, in which case the value is passed to Erlang's :public_key module as-is. Examples of acceptable values include 'character list' and {:utf8String, "string"}.

attr_list()

Specs

attr_list() :: [attr()]

List of RDN type/value pairs

t()

Specs

t() :: :public_key.issuer_name()

RDN sequence for use in OTP certificate and CSR records

Link to this section Functions

get_attr(arg, attr_type)

Specs

get_attr(t(), binary() | atom() | :public_key.oid()) :: [String.t()]

Extracts the values for the specified attributes from a :rdnSquence tuple.

The attribute type may be specified as an attribute name (long or short form, as a string, or long from as an atom) or an OID tuple. Refer to the documentation at the top of this module for a list of supported attributes.

Since an attribute may appear more than once in an RDN sequence the result is a list of values.

Examples:

iex> X509.RDNSequence.new("/C=US/CN=Bob") |> X509.RDNSequence.get_attr(:countryName)
["US"]
iex> X509.RDNSequence.new("/C=US/CN=Bob") |> X509.RDNSequence.get_attr("commonName")
["Bob"]
iex> X509.RDNSequence.new("C=CN, givenName=麗") |> X509.RDNSequence.get_attr("GN")
["麗"]

new(rdn, type \\ :plain)

Specs

new(String.t() | attr_list(), :plain | :otp) :: t()

Creates a new :rdnSquence tuple.

The value can be specified in one of the following formats:

A string specifying the attributes in hierarchical format, e.g. "/C=US/ST=NT/L=Springfield/O=ACME Inc."
A string specifying a comma-separated list of attributes, e.g. "C=US, ST=NT, L=Springfield, O=ACME Inc."
An RDN attribute list (see type documentation)

Note that the string parsers for the first two formats do not (currently) recognize escape characters: separator characters ('/' and ',', respectively) are not allowed in attribute values.

The optional second parameter can be used to select the output format:

:plain - for use in :Certificate and :CertificationRequest records (default)
:otp - for use in :OTPCertificate records (see X509.Certificate)

Raises an error when the given value cannot be parsed, contains unsupported attribute types, when attribute values exceed the maximum length ('upper bound' in the RFC) or when values cannot be coerced into the expected ASN.1 type.

Examples:

iex> X509.RDNSequence.new("/C=US/CN=Bob")
{:rdnSequence,
 [
   [{:AttributeTypeAndValue, {2, 5, 4, 6}, <<19, 2, 85, 83>>}],
   [{:AttributeTypeAndValue, {2, 5, 4, 3}, <<12, 3, 66, 111, 98>>}]
 ]}

iex> X509.RDNSequence.new("C=CN, givenName=麗")
{:rdnSequence,
 [
   [{:AttributeTypeAndValue, {2, 5, 4, 6}, <<19, 2, 67, 78>>}],
   [{:AttributeTypeAndValue, {2, 5, 4, 42}, <<12, 3, 233, 186, 151>>}]
 ]}

iex> X509.RDNSequence.new(commonName: "Elixir")
{:rdnSequence,
 [
   [{:AttributeTypeAndValue, {2, 5, 4, 3}, <<12, 6, 69, 108, 105, 120, 105, 114>>}]
 ]}

iex> X509.RDNSequence.new(language: "Elixir")
** (FunctionClauseError) no function clause matching in X509.RDNSequence.new_attr/1

iex> X509.RDNSequence.new("C=!!")
** (ArgumentError) unsupported character(s) in `PrintableString` attribute

to_string(arg)

Specs

to_string(t()) :: String.t()

Converts an :rdnSquence tuple to a human readable string, in hierarchical format.

Examples:

iex> X509.RDNSequence.new("C=CN, givenName=麗") |> X509.RDNSequence.to_string
"/C=CN/GN=麗"