China has recently implemented upgrades to its ‘Great Firewall’ in an effort to crack down on the use of Transport Layer Security (TLS) encryption-based tools, which are commonly used by citizens to evade the country’s censorship system.
The term ‘Great Firewall of China’ refers to the combination of tools, rules, and services enforced by the Chinese government to block specific internet content within the country.
According to the Great Firewall Report, an organization that monitors China’s censorship methods, over 100 users have reported the blocking of at least one of their TLS-based censorship circumvention servers.
These reports began on October 3, with the blocked circumvention protocols including trojan, Xray, V2Ray TLS+Websocket, VLESS, and gRPC.
“The blocking is done by blocking the specific port that the circumvention services listen on. When the user changes the blocked port to a non-blocked port and continues to use the circumvention tools, the entire IP addresses may get blocked,” reported the organization.
Interestingly, none of the domain names are added to the Great Firewall’s DNS or SNI blacklists. The report also noted that in some cases, the blocking appears to be dynamic, as web browsers can still access the circumvention ports, but the tools themselves do not work.
The organization suspects that the blocking may be related to the TLS fingerprints of the circumvention tools. They plan to investigate whether the Great Firewall uses these TLS fingerprints to identify circumvention protocols.
This update to the Great Firewall may be connected to the upcoming 20th National Congress of the Chinese Communist Party scheduled for October 16. During this congress, China’s leaders will discuss the country’s strategy for the next five years. The congress is crucial for China to achieve President Xi Jinping’s “Two Centenaries” goals that aim to make China a leading global power by 2049, as per the state-backed People’s Daily.
China is notorious for blocking numerous online services used for communication and information dissemination that may undermine the reputation of the Chinese government. Impartial news organizations like the BBC and CNN, major social media platforms such as Facebook, Twitter, Instagram, WhatsApp, and Reddit are all blocked. Additionally, the entire Google suite, including Gmail, Google Drive, and Maps, is inaccessible. Even platforms like YouTube and Slack are prohibited in the country.
In 2018, Google faced criticism after it was revealed that the company was secretly working on a search engine exclusively for use in China, enabling government censorship of search results. Known as ‘Project Dragonfly,’ this project was ultimately abandoned in 2019 due to employee backlash. The search engine would have allowed censorship on topics like human rights, democracy, and peaceful protests.