HONG KONG — The decision by a former National Security Agency contractor to divulge classified data about the United States government’s surveillance of computers in mainland China and Hong Kong has complicated his legal position, but may also make China’s security apparatus more interested in helping him stay here, law and security experts said on Friday.

The South China Morning Post, a local newspaper, reported on Friday that Edward J. Snowden, the contractor, had shared detailed data showing the dates and Internet Protocol addresses of specific computers in mainland China and Hong Kong that the National Security Agency penetrated over the last four years. The data also showed whether the agency was still breaking into these computers, the success rates for hacking and other operational information.

Mr. Snowden told the newspaper that the computers were in the civilian sector. But Western experts have long said that the dividing line between the civilian sector and the government is very blurry in China. State-owned or state-controlled enterprises still control much of the economy, and virtually all are run by Communist Party cadres who tend to rotate back and forth between government and corporate jobs every few years as part of elaborate career development procedures.

Kevin Egan, a former prosecutor here who has represented people fighting extradition to the United States, said that Mr. Snowden’s latest disclosures would make it harder for him to fight an expected request by the United States for him to be turned over to American law enforcement. “He’s digging his own grave with a very large spade,” he said.