Added sources for the first phrase.

Hariuha - according to Anders Hultgård, is suggested to contain the Germanic noun 'harja' (found on the Vimose Comb).

Hariuha could be a name, but I think in the context of this song calling for protection and returning safe from war, 'harja' could possibly mean commander or warrior (of the army).

'laþu laukar gakar alu' has one translation (among many others): 'invitation, invocation - leek, prosperity ... magic, intoxicating drink, protection' from here.