External SSO provider but discourse logs say None has already expired (please help!)

SSO
1

We are using Firebase as our external SSO provider. We have followed the discourse instructions on this.

We get an error in the logs as follows:

Verbose SSO log: Started SSO Process add_groups: admin: moderator: avatar_force_update: avatar_url: bio: card_background_url: email: external_id: groups: locale: locale_force_update: logo

Verbose SSO log: Nonce has already expired add_groups: admin: moderator: avatar_force_update: avatar_url: bio: card_background_url: email: [real email]: external_id: [external id]

We also see in the discourse logs:

Verbose SSO log: Started SSO process

add_groups: 
admin: 
moderator: 
avatar_force_update: 
avatar_url: 
bio: 
card_background_url: 
email: 
external_id: 
groups: 
locale: 
locale_force_update: 
logout: 
name: 
nonce: 773cb9d08db7007c9fb833e6c5e3a701
profile_background_url: 
remove_groups: 
require_activation: 
return_sso_url: https://discouse-site/session/sso_login
suppress_welcome_message: 
title: 
username: 
website: 
location:

AND

Verbose SSO log: Nonce has already expired

add_groups: 
admin: 
moderator: 
avatar_force_update: 
avatar_url: 
bio: 
card_background_url: 
email: [real email]
external_id: Be06ze0v0YO7I8SArWRoUVsxJ1k1
groups: 
locale: 
locale_force_update: 
logout: 
name: [real email]
nonce: Ym05dVkyVTlOV0kwTTJVeU1UTTVNamN6TnpNd01UbG1aVEJtWkRjMFlqTmtOV1U1TmpJbWNtVjBkWEp1WDNOemIxOTFjbXc5YUhSMGNITWxNMEVsTWtZbE1rWmpiMjF0ZFc1cGRIa3VZbTl2Wnk1aGNIQWxNa1p6WlhOemFXOXVKVEpHYzNOdlgyeHZaMmx1
profile_background_url: 
remove_groups: 
require_activation: 
return_sso_url: https://discouse-site/session/sso_login
suppress_welcome_message: 
title: 
username: [real email]
website: 
location:

Any help from the discourse team would be appreciated as we are currently unable to use the site.

James

2

I’m not expert in such, but my guess is to check whether your clock is correct.

3

Thanks for the suggestion but the clock doesn’t appear to be the issue. The discourse server and server from which the nonce is generated is on the same time.

1 Like
4

I am sharing the way that we generate the return url, to hopefully shed some more light on this problem:

   public String generateSSORedirectURL(String nonce, String email, String uid) {

    //generate the return payload
    HashMap<String, String> params = new HashMap<String, String>();
    params.put("nonce", nonce);
    params.put("external_id",uid);
    params.put("email",email);
    params.put("username",email);
    params.put("require_activation","false");
    params.put("name",email);
    params.put("return_sso_url","https://discourse-site/session/sso_login");
    log.info("params {}", params);

    //prepare the return payload
    String encodedParams = params.keySet().stream()
        .map(key -> key + "=" + encodeValue(params.get(key)))
        .collect(Collectors.joining("&"));
    log.info("encoded parameters {}", encodedParams);

    String returnPayload = Base64.getEncoder().encodeToString(encodedParams.getBytes());
    log.info("return Payload {}", returnPayload);

    //calculate the hmacSha256 signature for the payload
    byte[] hmacSha256 = calcHmacSha256(ssoSecret.getBytes(), returnPayload.getBytes());
    log.info("hmacSha256 sig {}", hmacSha256);
    
    String hmacSha265Hex = String.format("%x", new BigInteger(1, hmacSha256));
    log.info("hmacSha256, sig in Hex {}", String.format("%x", new BigInteger(1, hmacSha256)));

    HashMap<String, String> params2 = new HashMap<String, String>();
    params2.put("sig", hmacSha265Hex);
    params2.put("sso", returnPayload);
    log.info("params2 {}", params);

    String encodedParams2 = params2.keySet().stream()
        .map(key -> key + "=" + encodeValue(params2.get(key)))
        .collect(Collectors.joining("&"));
    log.info("encoded parameters {}", encodedParams2);

    //build and return the query string
    String queryString = forumUrl + "session/sso_login?" + encodedParams2;
    log.info("queryString {}", queryString);

    return queryString;
}
5

Did you ever figure this out? @James_Hope