Do not allow wildcards in the hostname for Valid Redirect Address (#48793)

Closes #48430

Signed-off-by: rmartinc <rmartinc@redhat.com>

 src/main/java/org/keycloak/protocol/cas/utils/RedirectUtils.java

@@ -180,7 +180,9 @@
            if ("*".equals(validRedirect)) {
                // the valid redirect * is a full wildcard for http(s) even if the redirect URI does not allow wildcards
                return validRedirect;
            } else if (validRedirect.endsWith("*") && !validRedirect.contains("?") && allowWildcards) {
            } else {
                String validRedirectWildcard = allowWildcards ? checkValidRedirectWildcard(validRedirect) : null;
                if (validRedirectWildcard != null) {
                // strip off the query or fragment components - we don't check them when wildcards are effective
                int idx = redirect.indexOf('?');
                if (idx == -1) {
@@ -188,14 +190,47 @@
                }
                String r = idx == -1 ? redirect : redirect.substring(0, idx);
                // strip off *
                int length = validRedirect.length() - 1;
                validRedirect = validRedirect.substring(0, length);
                if (r.startsWith(validRedirect)) return validRedirect;
                    int length = validRedirectWildcard.length() - 1;
                    validRedirectWildcard = validRedirectWildcard.substring(0, length);
                    if (r.startsWith(validRedirectWildcard)) {
                        return validRedirectWildcard;
                    }
                // strip off trailing '/'
                if (length - 1 > 0 && validRedirect.charAt(length - 1) == '/') length--;
                validRedirect = validRedirect.substring(0, length);
                if (validRedirect.equals(r)) return validRedirect;
            } else if (validRedirect.equals(redirect)) return validRedirect;
                    if (length - 1 > 0 && validRedirectWildcard.charAt(length - 1) == '/') {
                        length--;
                    }
                    validRedirectWildcard = validRedirectWildcard.substring(0, length);
                    if (validRedirectWildcard.equals(r)) {
                        return validRedirectWildcard;
                    }
                } else if (validRedirect.equals(redirect)) {
                    return validRedirect;
                }
            }
        }
        return null;
    }

    private static String checkValidRedirectWildcard(String validRedirect) {
        if (!validRedirect.endsWith("*") || validRedirect.contains("?") || validRedirect.contains("#")) {
            return null; // no wildcard as before
        }
        KeycloakUriBuilder uriBuilder = KeycloakUriBuilder.fromUri(validRedirect, false);
        if (uriBuilder.getPath() != null) {
            return validRedirect; // wildcard valid on path
        }
        if (uriBuilder.getAuthority() != null) {
            if (uriBuilder.getAuthority().equals("*") || uriBuilder.getAuthority().endsWith(":*")) {
                return validRedirect; // on authority just full wildcard or on port
            } else {
                // treat the wildcard after the authority
                validRedirect = validRedirect.substring(0, validRedirect.length() - 1);
                validRedirect = validRedirect + "/*";
                return validRedirect;
            }
        }
        if (uriBuilder.getSsp() != null) {
            return validRedirect; // wildcard valid on SSP
        }
        return null;
    }