gitcredentials(7)
=================
NAME
----
gitcredentials - providing usernames and passwords to Git
SYNOPSIS
--------
------------------
git config credential.https://example.com.username myusername
git config credential.helper "$helper $options"
------------------
DESCRIPTION
-----------
Git will sometimes need credentials from the user in order to perform
operations; for example, it may need to ask for a username and password
in order to access a remote repository over HTTP. This manual describes
the mechanisms Git uses to request these credentials, as well as some
features to avoid inputting these credentials repeatedly.
REQUESTING CREDENTIALS
----------------------
Without any credential helpers defined, Git will try the following
strategies to ask the user for usernames and passwords:
1. If the `GIT_ASKPASS` environment variable is set, the program
specified by the variable is invoked. A suitable prompt is provided
to the program on the command line, and the user's input is read
from its standard output.
2. Otherwise, if the `core.askPass` configuration variable is set, its
value is used as above.
3. Otherwise, if the `SSH_ASKPASS` environment variable is set, its
value is used as above.
4. Otherwise, the user is prompted on the terminal.
AVOIDING REPETITION
-------------------
It can be cumbersome to input the same credentials over and over. Git
provides two methods to reduce this annoyance:
1. Static configuration of usernames for a given authentication context.
2. Credential helpers to cache or store passwords, or to interact with
a system password wallet or keychain.
The first is simple and appropriate if you do not have secure storage available
for a password. It is generally configured by adding this to your config:
---------------------------------------
[credential "https://example.com"]
username = me
---------------------------------------
Credential helpers, on the other hand, are external programs from which Git can
request both usernames and passwords; they typically interface with secure
storage provided by the OS or other programs.
To use a helper, you must first select one to use. Git currently
includes the following helpers:
cache::
Cache credentials in memory for a short period of time. See
linkgit:git-credential-cache[1] for details.
store::
Store credentials indefinitely on disk. See
linkgit:git-credential-store[1] for details.
You may also have third-party helpers installed; search for
`credential-*` in the output of `git help -a`, and consult the
documentation of individual helpers. Once you have selected a helper,
you can tell Git to use it by putting its name into the
credential.helper variable.
1. Find a helper.
+
-------------------------------------------
$ git help -a | grep credential-
credential-foo
-------------------------------------------
2. Read its description.
+
-------------------------------------------
$ git help credential-foo
-------------------------------------------
3. Tell Git to use it.
+
-------------------------------------------
$ git config --global credential.helper foo
-------------------------------------------
CREDENTIAL CONTEXTS
-------------------
Git considers each credential to have a context defined by a URL. This context
is used to look up context-specific configuration, and is passed to any
helpers, which may use it as an index into secure storage.
For instance, imagine we are accessing `https://example.com/foo.git`. When Git
looks into a config file to see if a section matches this context, it will
consider the two a match if the context is a more-specific subset of the
pattern in the config file. For example, if you have this in your config file:
--------------------------------------
[credential "https://example.com"]
username = foo
--------------------------------------
then we will match: both protocols are the same, both hosts are the same, and
the "pattern" URL does not care about the path component at all. However, this
context would not match:
--------------------------------------
[credential "https://kernel.org"]
username = foo
--------------------------------------
because the hostnames differ. Nor would it match `foo.example.com`; Git
compares hostnames exactly, without considering whether two hosts are part of
the same domain. Likewise, a config entry for `http://example.com` would not
match: Git compares the protocols exactly.
If the "pattern" URL does include a path component, then this too must match
exactly: the context `https://example.com/bar/baz.git` will match a config
entry for `https://example.com/bar/baz.git` (in addition to matching the config
entry for `https://example.com`) but will not match a config entry for
`https://example.com/bar`.
CONFIGURATION OPTIONS
---------------------
Options for a credential context can be configured either in
`credential.*` (which applies to all credentials), or
`credential.<url>.*`, where <url> matches the context as described
above.
The following options are available in either location:
helper::
The name of an external credential helper, and any associated options.
If the helper name is not an absolute path, then the string `git
credential-` is prepended. The resulting string is executed by the
shell (so, for example, setting this to `foo --option=bar` will execute
`git credential-foo --option=bar` via the shell. See the manual of
specific helpers for examples of their use.
+
If there are multiple instances of the `credential.helper` configuration
variable, each helper will be tried in turn, and may provide a username,
password, or nothing. Once Git has acquired both a username and a
password, no more helpers will be tried.
+
If `credential.helper` is configured to the empty string, this resets
the helper list to empty (so you may override a helper set by a
lower-priority config file by configuring the empty-string helper,
followed by whatever set of helpers you would like).
username::
A default username, if one is not provided in the URL.
useHttpPath::
By default, Git does not consider the "path" component of an http URL
to be worth matching via external helpers. This means that a credential
stored for `https://example.com/foo.git` will also be used for
`https://example.com/bar.git`. If you do want to distinguish these
cases, set this option to `true`.
CUSTOM HELPERS
--------------
You can write your own custom helpers to interface with any system in
which you keep credentials. See the documentation for Git's
link:technical/api-credentials.html[credentials API] for details.
GIT
---
Part of the linkgit:git[1] suite
