1 SECURITY OF MERCURIAL-SERVER

     2 

     3 mercurial-server relies entirely on sshd to grant access to remote users.

     4 As a result, it runs no daemons, installs no setuid programs, and no part

     5 of it runs as root except the install process: all programs run as the user

     6 hg. And any attack on mercurial-server can only be started if the Bad Guys

     7 already have a public key in ~hg/.ssh/authorized_keys, otherwise sshd will

     8 bar the way.

     9 

    10 No matter what command the user tries to run on the remote system via ssh,

    11 mercurial-server is run. It parses the command line the user asked for, and

    12 interprets and runs the corresponding hg operation itself if access is

    13 allowed, so users can only read and add to history within repositories;

    14 they cannot run any other hg command. In addition, every push and pull is

    15 logged with a datestamp, changeset ID and the key that performed the

    16 operation.

    17 

    18 However, while the first paragraph holds no matter what bugs

    19 mercurial-server contains, the second depends on the relevant code being

    20 correct; though the entire codebase is short, mercurial-server is a fairly

    21 new program and may harbour bugs. Backups are essential!