Squid internals

Authentication
Main functions
auth_user = authenticateAuthUserNew(scheme)
/* Create a new user auth of type 'scheme' */
auth_user_request = authenticateAuthUserRequestNew(void)
/* Create a new user auth request */
authenticateStart(auth_user_request, handler, data)
/* Start user authentication */
authenticateValidateUser(auth_user_request)
/* Check the auth_user_request for validity */
authenticateAuthenticateUser(auth_user_request, request, conn, http_hdr_type)
/* Attempt to authenticate this user */
authenticateAuthUserLock/userUnlock(auth_user)
/* Lock and unlock the auth_user (needed for caching!) */
authenticateAuthUserRequestLock/ RequestUnlock(auth_user_request)
/* Same as above! */
authenticateProxyUserCacheCleanup(unused)
/* Clean out the authentication cache */