Term for a former prisoner, who seems to have an aura of jail hanging around him

There are a few metaphors that occur in Jo's Boys that resemble what you're talking about.

pp. 263: "They'd see and smell and feel the prison taint on me..."

pp. 327: "He longed to go home, but waited week after week to get the prison taint off him and the haggard look out of his face."

pp. 338: "All the old prison gloom seemed to settle like a black cloud on Dan's face..."

pp. 343: "... and to help wear away the first sharpness of the prison brand."

A person who has done time is often called a "jailbird", an "ex-con", an "old lag"...