Security fix: Disallow hostname starting with a dash, which would get
passed to ssh and be treated an option. This could be used by an attacker
who provides a crafted ssh url (for eg a git remote) to execute arbitrary
code via ssh -oProxyCommand.
No CVE has yet been assigned for this hole.
The same class of security hole recently affected git itself,
CVE-2017-1000117.
Method: Identified all places where ssh is run, by git grep '"ssh"'
Converted them all to use a SshHost, if they did not already, for
specifying the hostname.
SshHost was made a data type with a smart constructor, which rejects
hostnames starting with '-'.
Note that git-annex already contains extensive use of Utility.SafeCommand,
which fixes a similar class of problem where a filename starting with a
dash gets passed to a program which treats it as an option.
This commit was sponsored by Jochen Bartl on Patreon.
External special remotes will refuse to operate on keys with spaces in
their names. That has never worked correctly due to the design of the
external special remote protocol. Display an error message suggesting
migration.
Not super happy with this, but it's a pragmatic solution. Better than
complicating the external special remote interface and all external special
remotes.
Note that I only made it use SafeKey in Request, not Response. git-annex
does not construct a Response, so that would not add any safety. And
presumably, if git-annex avoids feeding any such keys to an external
special remote, it will never have a reason to make a Response using such a
key. If it did, it would result in a protocol error anyway.
There's still a Serializeable instance for Key; it's used by P2P.Protocol.
There, the Key is always in the final position, so it's ok if it contains
spaces.
Note that the protocol documentation has been fixed to say that the File
may contain spaces. One way that can happen, even though the Key can't,
is when using direct mode, and the work tree filename contains spaces.
When sending such a file to the external special remote the worktree
filename is used.
This commit was sponsored by Thom May on Patreon.
Added remote configuration settings annex-ignore-command and
annex-sync-command, which are dynamic equivilants of the annex-ignore
and annex-sync configurations.
For this I needed a new DynamicConfig infrastructure. Its implementation
should be as fast as before when there is no dynamic config, and it caches
so shell commands are only run once.
Note that annex-ignore-command exits nonzero when the remote should be ignored.
While that may seem backwards, it allows using the same command for it as
for annex-sync-command when you want to disable both.
This commit was sponsored by Trenton Cronholm on Patreon.
Removed dependency on MissingH, instead depending on the split
library.
After laying groundwork for this since 2015, it
was mostly straightforward. Added Utility.Tuple and
Utility.Split. Eyeballed System.Path.WildMatch while implementing
the same thing.
Since MissingH's progress meter display was being used, I re-implemented
my own. Bonus: Now progress is displayed for transfers of files of
unknown size.
This commit was sponsored by Shane-o on Patreon.
This was never supported before. And it doesn't re-encrypt the
gcrypt repo to the new gcrypt-participants, but it does at least now not
crash, and set gcrypt-participants.
This commit was sponsored by andrea rota.
They are handled close the same as they are by git. However, unlike git,
git-annex sometimes needs to pass the -n parameter when using these.
So, this has the potential for breaking some setup, and perhaps there ought
to be a ANNEX_USE_GIT_SSH=1 needed to use these. But I'd rather avoid that
if possible, so let's see if anyone complains.
Almost all places where "ssh" was run have been changed to support the env
vars. Anything still calling sshOptions does not support them. In
particular, rsync special remotes don't. Seems that annex-rsync-transport
already gives sufficient control there.
(Fixed in passing: Remote.Helper.Ssh.toRepo used to extract
remoteAnnexSshOptions and pass them to sshOptions, which was redundant
since sshOptions also extracts those.)
This commit was sponsored by Jeff Goeke-Smith on Patreon.
findShellCommand needs a full path to a file in order to check it for a
shebang on Windows. It was being run with only the base name of the external
special remote program, which would only work when it was in the current
directory.
This is why users in
https://github.com/DanielDent/git-annex-remote-rclone/pull/10 and elsewhere
were complaining that the previous improvements to git-annex didn't make
git-remote-rclone work on Windows.
Also, reworked checkearlytermination, which while it worked, seemed
to rely on a race condition. And, improved its error messages.
This commit was sponsored by Shane-o on Patreon.
sync: When syncing with a local repository located on a crippled
filesystem, run the post-receive hook there, since it wouldn't get run
otherwise. This makes pushing to repos on FAT-formatted removable drives
update them when receive.denyCurrentBranch=updateInstead.
Made Remote.Git export onLocal, which was cleaned up to not have so many
caveats about its use.
This commit was sponsored by Jeff Goeke-Smith on Patreon.
... to avoid it consuming stdin that it shouldn't.
This fixes git-annex-checkpresentkey --batch remote, which didn't output
results for all keys passed into it.
Other git-annex commands that communicate with a remote over ssh may also
have been consuming stdin that they shouldn't have, which could have
impacted using them in eg, shell scripts. For example, a shell script
reading files from stdin and passing them to git annex drop would be
impacted by this bug, whenever git annex drop ran git-annex-shell
checkpresent, it would consume part/all of the stdin that the shell script
was supposed to consume.
Fixed by adding a ConsumeStdin parameter to Annex.Ssh.sshOptions, which
is used throughout git-annex to run ssh (in order for ssh connection
caching to work). Every call site was checked to see if it used
CreatePipe for stdin, and if not was marked NoConsumeStdin.
The check was broken in two ways.. First, nowhere did it error out when
checkUUIDFile found a different UUID already in the file. Instead,
it overwrote the uuid file.
And, checkUUIDFile's implementation was for some reason always failing with
a ConnectionClosed exception. Apparently something to do with using two
different runResourceT's and a response getting GCed inbetween. I'm pretty
sure that used to work, but changed to a more obviously correct
implementation.
This commit was sponsored by Peter Hogg on Patreon.
Most remotes have an idempotent setup that can be reused for
enableremote, but in a few cases, it needs to tell which, and whether
a UUID was provided to setup was used.
This is groundwork for making initremote be able to provide a UUID.
It should not change any behavior.
Note that it would be nice to make the UUID always be provided to setup,
and make setup not need to generate and return a UUID. What prevented
this simplification is Remote.Git.gitSetup, which needs to reuse the
UUID of the git remote when setting it up, and so has to return that
UUID.
This commit was sponsored by Thom May on Patreon.
Turns out that Data.List.Utils.split is slow and makes a lot of
allocations. Here's a much simpler single character splitter that behaves
the same (even in wacky corner cases) while running in half the time and
75% the allocations.
As well as being an optimisation, this helps move toward eliminating use of
missingh.
(Data.List.Split.splitOn is nearly as slow as Data.List.Utils.split and
allocates even more.)
I have not benchmarked the effect on git-annex, but would not be surprised
to see some parsing of eg, large streams from git commands run twice as
fast, and possibly in less memory.
This commit was sponsored by Boyd Stephen Smith Jr. on Patreon.
The attacker could just send a very lot of data, with no \n and it would
all be buffered in memory until the kernel killed git-annex or perhaps OOM
killed some other more valuable process.
This is a low impact security hole, only affecting communication between
local git-annex and git-annex-shell on the remote system. (With either
able to be the attacker). Only those with the right ssh key can do it. And,
there are probably lots of ways to construct git repositories that make git
use a lot of memory in various ways, which would have similar impact as
this attack.
The fix in P2P/IO.hs would have been higher impact, if it had made it to a
released version, since it would have allowed DOSing the tor hidden
service without needing to authenticate.
(The LockContent and NotifyChanges instances may not be really
exploitable; since the line is read and ignored, it probably gets read
lazily and does not end up staying buffered in memory.)
Display progress meter on send and receive from remote.
Added a new hGetMetered that can read an exact number of bytes (or
less), updating a meter as it goes.
This commit was sponsored by Andreas on Patreon.
In case the repo on the peer changes uuid (eg by a new repo being moved
into place).
Also, added some warning messages when unable to communicate with a
peer.
This commit was sponsored by Anthony DeRobertis on Patreon.
Not tested at all, but it just might work.
Only known problem is that progress is not updated when storing to a P2P
remote.
This commit was sponsored by Nick Daly on Patreon.
Similar to GCrypt remotes, P2P remotes have an url, so Remote.Git has to
separate them out and handle them, passing off to Remote.P2P.
This commit was sponsored by Ignacio on Patreon.
git upload-pack makes some uncessary writes in sequence, this tries to
gather them together to avoid needing to send multiple DATA packets when
just one will do.
In a small pull, this reduces the average number of DATA packets from
4.5 to 2.5.
Still a couple bugs:
* Closing the connection to the server leaves git upload-pack /
receive-pack running, which could be used to DOS.
* Sometimes the data is transferred, but it fails at the end, sometimes
with:
git-remote-tor-annex: <socket: 10>: commitBuffer: resource vanished (Broken pipe)
Must be a race condition around shutdown.
Almost working, but there's a bug in the relaying.
Also, made tor hidden service setup pick a random port, to make it harder
to port scan.
This commit was sponsored by Boyd Stephen Smith Jr. on Patreon.
This is most of the way to having the p2p protocol working over tor
hidden services, at least enough to do git push/pull.
The free monad was split into two, one for network operations and the
other for local (Annex) operations. This will allow git-remote-tor-annex
to run only an IO action, not needing the Annex monad.
This commit was sponsored by Remy van Elst on Patreon.