1git-annex-shell(1) General Commands Manual git-annex-shell(1)
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6 git-annex-shell - Restricted login shell for git-annex only SSH access
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9 git-annex-shell [-c] command [params ...]
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12 git-annex-shell is a restricted shell, similar to git-shell, which can
13 be used as a login shell for SSH accounts.
14 Since its syntax is identical to git-shell's, it can be used as a
16 drop-in replacement anywhere git-shell is used. For example it can be
17 used as a user's restricted login shell.
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20 Any command not listed below is passed through to git-shell.
21 Note that the directory parameter should be an absolute path, otherwise
23 it is assumed to be relative to the user's home directory. Also the
24 first "/~/" or "/~user/" is expanded to the specified home directory.
25 configlist directory
27 This outputs a subset of the git configuration, in the same form
28 as git config --list. This is used to get the annex.uuid of the
29 remote repository.
30 When run in a repository that does not yet have an annex.uuid,
32 one will be created, as long as a git-annex branch has already
33 been pushed to the repository, or if the autoinit=1 flag is used
34 to indicate initialization is desired.
35 p2pstdio directory uuid
37 This causes git-annex-shell to communicate using the git-annex
38 p2p protocol over stdio.
39 The uuid is the one belonging to the repository that will be
41 communicating with git-annex-shell.
42 notifychanges directory
44 This is used by git-annex remotedaemon to be notified when refs
45 in the remote repository are changed.
46 gcryptsetup directory gcryptid
48 Sets up a repository as a gcrypt repository.
49 inannex directory [key ...]
51 This checks if all specified keys are present in the annex, and
52 exits zero if so.
53 Exits 1 if the key is certainly not present in the annex. Exits
55 100 if it's unable to tell (perhaps the key is in the process of
56 being removed from the annex).
57 Used only by the gcrypt special remote.
59 recvkey directory key
61 This runs rsync in server mode to receive the content of a key,
62 and stores the content in the annex.
63 Used only by the gcrypt special remote.
65 sendkey directory key
67 This runs rsync in server mode to transfer out the content of a
68 key.
69 Used only by the gcrypt special remote.
71 dropkey directory [key ...]
73 This drops the annexed data for the specified keys.
74 Used only by the gcrypt special remote.
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78 --uuid=UUID
79 git-annex uses this to specify the UUID of the repository it was
81 expecting git-annex-shell to access, as a sanity check.
82 Also the git-annex-common-options(1) can be used.
84 -- fields=val fields=val.. --
86 Additional fields may be specified this way, to retain compati‐
87 bility with past versions of git-annex-shell (that ignore these,
88 but would choke on new dashed options).
89 Currently used fields are autoinit= and remoteuuid=
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93 After content is received or dropped from the repository by git-an‐
94 nex-shell, it runs a hook, .git/hooks/annex-content (or hooks/an‐
95 nex-content on a bare repository). The hook is not currently passed any
96 information about what changed.
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99 GIT_ANNEX_SHELL_READONLY
100 If set, disallows any action that could modify the git-annex
102 repository.
103 Note that this does not prevent passing commands on to
105 git-shell. For that, you also need ...
106 GIT_ANNEX_SHELL_LIMITED
108 If set, disallows running git-shell to handle unknown commands.
109 GIT_ANNEX_SHELL_APPENDONLY
111 If set, allows data to be written to the git-annex repository,
112 but does not allow data to be removed from it.
113 Note that this does not prevent passing commands on to
115 git-shell, so you will have to separately configure git to re‐
116 ject pushes that overwrite branches or are otherwise not ap‐
117 pends. The git pre-receive hook may be useful for accomplishing
118 this.
119 It's a good idea to enable annex.securehashesonly in a reposi‐
121 tory that's set up this way.
122 GIT_ANNEX_SHELL_DIRECTORY
124 If set, git-annex-shell will refuse to run commands that do not
125 operate on the specified directory.
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128 To make a ~/.ssh/authorized_keys file that only allows git-annex-shell
129 to be run, and not other commands, pass the original command to the -c
130 option:
131 command="git-annex-shell -c \"$SSH_ORIGINAL_COMMAND\"",no-agent-for‐
133 warding,no-port-forwarding,no-X11-forwarding ssh-rsa AAAAB3NzaC1y[...]
134 user@example.com
135 To further restrict git-annex-shell to a particular repository, and
137 fully lock it down to read-only mode:
138 command="GIT_ANNEX_SHELL_DIRECTORY=/srv/annex GIT_ANNEX_SHELL_LIM‐
140 ITED=true GIT_ANNEX_SHELL_READONLY=true git-annex-shell -c \"$SSH_ORIG‐
141 INAL_COMMAND\"",restrict ssh-rsa AAAAB3NzaC1y[...] user@example.com
142 Obviously, ssh-rsa AAAAB3NzaC1y[...] user@example.com needs to replaced
144 with your SSH key. The above also assumes git-annex-shell is available
145 in your $PATH, use an absolute path if it is not the case. Also note
146 how the above uses the restrict option instead of an explicit list of
147 functionality to disallow. This only works in certain OpenSSH releases,
148 starting from 7.1p2.
149 To only allow adding new objects to the repository, the GIT_AN‐
151 NEX_SHELL_APPENDONLY variable can be used as well:
152 command="GIT_ANNEX_SHELL_DIRECTORY=/srv/annex GIT_ANNEX_SHELL_APPEN‐
154 DONLY=true git-annex-shell -c \"$SSH_ORIGINAL_COMMAND\"",restrict
155 ssh-rsa AAAAB3NzaC1y[...] user@example.com
156 This will not keep an attacker from destroying the git history, as ex‐
158 plained above. For this you might want to disallow certain operations,
159 like branch deletion and force-push, with options from git-config(1).
160 For example:
161 git config receive.denyDeletes true git config receive.denyNonFastFor‐
163 wards true
164 With this configuration, git commits can still remove files, but they
166 will still be available in the git history and git-annex will retain
167 their contents. Changes to git-annex branch, however, can negatively
168 impact git-annex's location tracking information and might cause data
169 loss. To work around this problem, more complex hooks are required, see
170 for example the update-paranoid hook in the git source distribution.
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173 git-annex(1)
174 git-shell(1)
176
178 Joey Hess <id@joeyh.name>
179 <http://git-annex.branchable.com/>
181 git-annex-shell(1)