O’Halloran will replace Marcos Painter who have suffered a serious injury.
“I’m looking forward to the challenge,” O’Halloran told the club’s official website. “I know this Swansea side plays good football and I think it will suit my style of play.
“I like to get forward whenever I can, but my main job is to help keep a clean sheet.
“I watched Swansea play Cardiff in the Carling Cup a few weeks ago live on Sky. They played really well and there looked a fantastic atmosphere at the Liberty Stadium.
“I’m really looking forward to pushing for a starting place. My aim is to get as many games as possible under my belt, improve my match fitness and help the Swans push up the Championship table.
“I’m out of contract at the end of the season, so I need to impress both managers – at Aston Villa and Swansea.”
