According to the factbooks released alongside the film, Han has indeed returned to a life of crime.
From Star Wars: The Force Awakens: The Visual Dictionary
After the Galactic Civil War, Han Solo's life took unexpected turns as
he became husband to an influential New Republic politician, a family
man and - for a time - successful racing pilot. But the peace of this
life as not to last, and after a profound tragedy upended what had
become normal for the Corellian, Solo returned to his old life as a
tramp freighter captain, smuggler and freelance law bender.
As easily as the Millennium Falcon fell into Solo's life after a
heated game of sabacc, so it was destined to abandon him after a
change in fate. Solo made do with other ships at his disposal,
eventually settling on an enormous bulk freighter named the Eravana,
which he uses to haul massive shipments of legally questionable cargo. The ship is largely automated, meaning Solo and Chewbacca can
handle most of the work, but on particularly dangerous or profitable
hauls he hires additional hands.
From Star Wars: Incredible Cross Sections - The Force Awakens we see that Han is carrying stolen items, illegal speeders and black-market animals such as Rathtars.
The film's junior novelisation also makes note that they're instantly identifiable as smugglers
The pair who came aboard the Millennium Falcon were not stormtroopers
but smugglers. One was old, human, and somewhat scruffy-looking. The
other was almost a half-meter taller and much hairier. They entered
the freighter with a measure of fondness and caution, as it had been a
long time since they’d walked down her corridors.