{"id":112279,"date":"2023-12-17T15:10:15","date_gmt":"2023-12-17T13:10:16","guid":{"rendered":"https:\/\/prohoster.info\/blog\/novosti-interneta\/predstavlen-ssh3-variant-protokola-ssh-ispolzuyushhij-http-3"},"modified":"2023-12-17T15:10:15","modified_gmt":"2023-12-17T13:10:16","slug":"predstavlen-ssh3-variant-protokola-ssh-ispolzuyushhij-http-3","status":"publish","type":"post","link":"https:\/\/prohoster.info\/en\/blog\/news\/predstavlen-ssh3-variant-protokola-ssh-ispolzuyushhij-http-3","title":{"rendered":"SSH3 has been introduced, a variant of the SSH protocol that uses HTTP\/3","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"

The first official release of the experimental implementation of the server and client for the SSH3 protocol is available, designed as an extension over the HTTP\/3 protocol, using QUIC (based on UDP) and TLS 1.3 to establish a secure communication channel, along with HTTP mechanisms for user authentication. The project is developed by Fran\u00e7ois Michel, a PhD student at the Catholic University of Leuven (Belgium), with the involvement of Olivier Bonaventure, a professor at the same university, known for developing the Multipath TCP subsystem and IPv6 segment routing code for the Linux kernel, as well as co-authoring 10 RFCs and drafts for more than 60 networking specifications. The reference implementation code for the client and server is written in Go and is distributed under the Apache 2.0 license. <\/p>\n

The development of SSH3 resulted from a complete overhaul of the SSH protocol conducted by a separate group of researchers independently from OpenSSH and other projects that are advancing implementations of the classic SSH protocol. In SSH3, the semantics of the classic SSH protocol are implemented through HTTP mechanisms, allowing for additional functionalities and ensuring the obfuscation of SSH-related activity amongst other traffic. <\/p>\n

When using SSH3, the server is indistinguishable from an HTTP server and accepts requests on port 443 (HTTPS), while the SSH3 traffic merges with standard HTTP traffic, making it difficult to conduct port scanning attacks and identify SSH servers for password guessing. To complicate the execution of attacks on servers<\/a> SSH3, in addition to providing details about the existence of a server at a given IP address, can specify a secret path-identifier for the SSH3 server. Without using the correct identifier, the server will handle requests as a regular HTTPS server and will not disclose the ability to connect via SSH3. For example, with the identifier 'e6ae772cbdaafd6918865cc2ce449dae', the connection to the server can only be made via the URL 'https:\/\/192.0.2.0:443\/e6ae772cbdaafd6918865cc2ce449dae', and if the identifier is specified incorrectly, the server will return the standard error '404'. <\/p>\n

The extended functionality of SSH3 includes the ability to use X.509 certificates and OAuth 2.0\/OpenID Connect methods for authentication, in addition to classic SSH methods; support for UDP port forwarding through an SSH tunnel as well as TCP port forwarding (e.g., for passing QUIC, DNS, and RTP); and the use of advanced features of the QUIC protocol, such as connection migration without interrupting connectivity and establishing multipath connections for parallelizing traffic across multiple routes. <\/p>\n

A significant reduction in connection setup time when using SSH3 is highlighted. Connecting to an SSH3 server requires only 3 network iterations (Round Trip), while SSHv2 requires 5-7 packet exchanges. The response time for keyboard input for already established sessions in both SSH3 and SSHv2 is at the same level.

\"SSH3<\/center> <\/p>\n

For encrypting the communication channel in SSH3, the TLS 1.3 protocol is used, and authentication can employ classic password-based methods and public key methods (RSA and EdDSA\/ed25519). Additionally, SSH3 can use methods based on OAuth 2.0, allowing for offloading authentication to third-party providers, such as enabling logins with confirmation via accounts on Google, Microsoft, and GitHub services. For connecting to servers using keys, besides SSH keys, X.509 certificates used for HTTPS can also be utilized. <\/p>\n

The published implementation of the SSH3 client and server supports many basic features of OpenSSH, including: <\/p>\n