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* ServerID* ClientSideCredential OuterIdentity? InnerIdentityPrefix? InnerIdentitySuffix? InnerIdentityHint? Username? UserName? Password? ClientCertificate? IntermediateCACertificate* 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, tags 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 tag is specified, then all user-displayable strings inside this tag are to be considered suitable for use in user interfaces in that language. Individual lang tags for the sub-tags inside EAPIdentityProvider then SHOULD NOT be used.
If the optional attribute "lang" for the EAPIdentityProvider tag is not set, individual sub-tags which contain user-displayable strings SHOULD be marked with the language they are written/available in.
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" we can have 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 gotten previous credentials before.
The user then needs to input his 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 container.