1.0. Introduction
The EAP metadata is returned as an XML. Clients MAY validate this metadata according to the XSD specification. If the validation matches, client can then parse it using an XML parser.
Note: This EAP XSD is modified from the CAT project at https://github.com/GEANT/CAT/blob/master/devices/xml/eap-metadata.xsd
1.1. General structure
An attempt was made to translate the XSD min- and maxOccurs to regex-like quantifiers.
No quantifiers means it needs to be present (once).
+ = (1 - unbound)
* = (0 - unbound)
? = (0 - 1).
EAPIdentityProviderList EAPIdentityProvider+ (version, lang, ID) ValidUntil? AuthenticationMethods+ AuthenticationMethod* EAPMethod? Type TypeSpecific VendorSpecific ServerSideCredential? CA* (format, encoding) ServerID* ClientSideCredential OuterIdentity? InnerIdentityPrefix? InnerIdentitySuffix? InnerIdentityHint? Username? UserName? Password? ClientCertificate? (format, encoding) IntermediateCACertificate* (format, encoding) Passphrase? PAC? ProvisionPAC? InnerAuthenticationMethod EAPMethod? NonEapMethod? Type TypeSpecific? VendorSpecific* ServerSideCredential? ClientSideCredential? CredentialApplicability IEEE80211* SSID? ConsortiumOID? MinRSNProto? IEEE8023* NetworkID ProviderInfo? DisplayName* Description* ProviderLocation* Longitude Latitude ProviderLogo (mime, encoding) TermsOfUse* Helpdesk? EmailAddress* WebAddress* Phone* VendorSpecific?
ClientCredential and ServerCredential
Not all EAP types and non-EAP authentication methods need or support all types of credentials in the list below.
While the Schema allows to put all kinds of credential information inside every AuthenticationMethod
, even where the information is not applicable, elements which are not applicable for an authentication EAP or non-EAP type SHOULD NOT be included in the corresponding instance of AuthenticationMethod
or InnerAuthenticationMethod
when producing the XML file, and MUST be ignored by the entity consuming the XML file if present in the XML file.
IEEE80211
The conditions inside this element are considered AND conditions. It does e.g. not make sense to have multiple SSIDs in one IEEE80211 field because the condition would never match.
To specify multiple ORed network properties, use multiple IEEE80211 instances.
EAPIdentityProvider
If the optional attribute lang
for the EAPIdentityProvider
element is specified, then all user-displayable strings inside this element are to be considered suitable for use in user interfaces in that language. Individual lang
attributes for the child elements inside EAPIdentityProvider
then SHOULD NOT be used.
If the optional attribute lang
for the EAPIdentityProvider
element is not set, individual child elements which contain user-displayable strings SHOULD be marked with the language they are written/available in.
InnerIdentity
The EAP metadatafile can contain extra information about the InnerIdentity, mostly used to streamline the realm specific InnerIdentity form element:
InnerIdentityPrefix
contains the required realm prefix if any. E.g. DOMAIN/InnerIdentitySuffix
contains the required realm suffix, if any. E.g. @DOMAINInnerIdentityHint
is a boolean, telling the app to populate the InnerIdentity field using the InnerIdentityPrefix or Suffix and placing the cursur a the correct place (after the / if prefix is used or before the @ in the case of suffix).
Certificates
ServerSideCredential
contains a list of CA's that should contain valid CA certificates.
ClientSideCredential
contains the client certificate, optionally protected by a passphrase
.
Certificates have a format and encoding attribute. The format should be X.509 and encoding base64.
1.1. Methods and authentication
The EAP metadata will have different methods and inner authentication methods defined. Below is a list that can be present in the eap file:
Methods (<EAPMethod><Type>...</Type></EAPMethod>
)
- 13: TLS
- 21: TTLS
- 25: PEAP
Inner authentication type (<InnerAuthenticationMethod><EAPMethod><Type>...</Type></EAPMethod></InnerAuthenticationMethod>
)
- 0: None
- 1: PAP
- 2: MSCHAP
- 3: MSCHAPv2
- 25: EAP_PEAP_MSCHAPv2
- 26: EAP_MSCHAPV2
Based on these authentication methods, there are various "flows" possible to continue connecting. We will discuss these in the next sections.
1.2. Needs login credentials
The first possibility is that the user needs to provide login credentials. This is the case where the authentication method is NOT TLS (meaning method code is NOT 13) and where the client has not received previous credentials before.
The user then needs to input her username (including the @REALM) and password in the UI. If there is a possibility that this can be automatically configured within the OS UI then this MUST be preferred.
1.3. Needs client certificate
If the authentication method is TLS then a client certificate (PKCS12) MUST be provided. If the client cannot read this certificate due to encryption, a passphrase
MUST be used to decrypt the ciphertext.