diff options
| author | Brandon Williams <bmwill@google.com> | 2017-10-16 20:55:28 +0300 |
|---|---|---|
| committer | Junio C Hamano <gitster@pobox.com> | 2017-10-17 04:51:29 +0300 |
| commit | 0c2f0d27038f2aa98082d8af35c53b2ec7e9ad92 (patch) | |
| tree | 2064f395a54ba9f5eb551d750bd5f265d1fdb369 /http.c | |
| parent | 2609043da00ea0db411c44179136b07bf210bf75 (diff) | |
connect: tell server that the client understands v1
Teach the connection logic to tell a serve that it understands protocol
v1. This is done in 2 different ways for the builtin transports, both
of which ultimately set 'GIT_PROTOCOL' to 'version=1' on the server.
1. git://
A normal request to git-daemon is structured as
"command path/to/repo\0host=..\0" and due to a bug introduced in
49ba83fb6 (Add virtualization support to git-daemon, 2006-09-19) we
aren't able to place any extra arguments (separated by NULs) besides
the host otherwise the parsing of those arguments would enter an
infinite loop. This bug was fixed in 73bb33a94 (daemon: Strictly
parse the "extra arg" part of the command, 2009-06-04) but a check
was put in place to disallow extra arguments so that new clients
wouldn't trigger this bug in older servers.
In order to get around this limitation git-daemon was taught to
recognize additional request arguments hidden behind a second
NUL byte. Requests can then be structured like:
"command path/to/repo\0host=..\0\0version=1\0key=value\0".
git-daemon can then parse out the extra arguments and set
'GIT_PROTOCOL' accordingly.
By placing these extra arguments behind a second NUL byte we can
skirt around both the infinite loop bug in 49ba83fb6 (Add
virtualization support to git-daemon, 2006-09-19) as well as the
explicit disallowing of extra arguments introduced in 73bb33a94
(daemon: Strictly parse the "extra arg" part of the command,
2009-06-04) because both of these versions of git-daemon check for a
single NUL byte after the host argument before terminating the
argument parsing.
2. ssh://, file://
Set 'GIT_PROTOCOL' environment variable with the desired protocol
version. With the file:// transport, 'GIT_PROTOCOL' can be set
explicitly in the locally running git-upload-pack or git-receive-pack
processes. With the ssh:// transport and OpenSSH compliant ssh
programs, 'GIT_PROTOCOL' can be sent across ssh by using '-o
SendEnv=GIT_PROTOCOL' and having the server whitelist this
environment variable.
Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Diffstat (limited to 'http.c')
0 files changed, 0 insertions, 0 deletions