6 gitcredentials - Providing usernames and passwords to Git
11 git config credential.https://example.com.username myusername
12 git config credential.helper "$helper $options"
18 Git will sometimes need credentials from the user in order to perform
19 operations; for example, it may need to ask for a username and password
20 in order to access a remote repository over HTTP. Some remotes accept
21 a personal access token or OAuth access token as a password. This
22 manual describes the mechanisms Git uses to request these credentials,
23 as well as some features to avoid inputting these credentials repeatedly.
25 REQUESTING CREDENTIALS
26 ----------------------
28 Without any credential helpers defined, Git will try the following
29 strategies to ask the user for usernames and passwords:
31 1. If the `GIT_ASKPASS` environment variable is set, the program
32 specified by the variable is invoked. A suitable prompt is provided
33 to the program on the command line, and the user's input is read
34 from its standard output.
36 2. Otherwise, if the `core.askPass` configuration variable is set, its
37 value is used as above.
39 3. Otherwise, if the `SSH_ASKPASS` environment variable is set, its
40 value is used as above.
42 4. Otherwise, the user is prompted on the terminal.
47 It can be cumbersome to input the same credentials over and over. Git
48 provides two methods to reduce this annoyance:
50 1. Static configuration of usernames for a given authentication context.
52 2. Credential helpers to cache or store passwords, or to interact with
53 a system password wallet or keychain.
55 The first is simple and appropriate if you do not have secure storage available
56 for a password. It is generally configured by adding this to your config:
58 ---------------------------------------
59 [credential "https://example.com"]
61 ---------------------------------------
63 Credential helpers, on the other hand, are external programs from which Git can
64 request both usernames and passwords; they typically interface with secure
65 storage provided by the OS or other programs.
67 To use a helper, you must first select one to use. Git currently
68 includes the following helpers:
72 Cache credentials in memory for a short period of time. See
73 linkgit:git-credential-cache[1] for details.
77 Store credentials indefinitely on disk. See
78 linkgit:git-credential-store[1] for details.
80 You may also have third-party helpers installed; search for
81 `credential-*` in the output of `git help -a`, and consult the
82 documentation of individual helpers. Once you have selected a helper,
83 you can tell Git to use it by putting its name into the
84 credential.helper variable.
88 -------------------------------------------
89 $ git help -a | grep credential-
91 -------------------------------------------
93 2. Read its description.
95 -------------------------------------------
96 $ git help credential-foo
97 -------------------------------------------
99 3. Tell Git to use it.
101 -------------------------------------------
102 $ git config --global credential.helper foo
103 -------------------------------------------
109 Git considers each credential to have a context defined by a URL. This context
110 is used to look up context-specific configuration, and is passed to any
111 helpers, which may use it as an index into secure storage.
113 For instance, imagine we are accessing `https://example.com/foo.git`. When Git
114 looks into a config file to see if a section matches this context, it will
115 consider the two a match if the context is a more-specific subset of the
116 pattern in the config file. For example, if you have this in your config file:
118 --------------------------------------
119 [credential "https://example.com"]
121 --------------------------------------
123 then we will match: both protocols are the same, both hosts are the same, and
124 the "pattern" URL does not care about the path component at all. However, this
125 context would not match:
127 --------------------------------------
128 [credential "https://kernel.org"]
130 --------------------------------------
132 because the hostnames differ. Nor would it match `foo.example.com`; Git
133 compares hostnames exactly, without considering whether two hosts are part of
134 the same domain. Likewise, a config entry for `http://example.com` would not
135 match: Git compares the protocols exactly. However, you may use wildcards in
136 the domain name and other pattern matching techniques as with the `http.<URL>.*`
139 If the "pattern" URL does include a path component, then this too must match
140 exactly: the context `https://example.com/bar/baz.git` will match a config
141 entry for `https://example.com/bar/baz.git` (in addition to matching the config
142 entry for `https://example.com`) but will not match a config entry for
143 `https://example.com/bar`.
146 CONFIGURATION OPTIONS
147 ---------------------
149 Options for a credential context can be configured either in
150 `credential.*` (which applies to all credentials), or
151 `credential.<URL>.*`, where <URL> matches the context as described
154 The following options are available in either location:
158 The name of an external credential helper, and any associated options.
159 If the helper name is not an absolute path, then the string `git
160 credential-` is prepended. The resulting string is executed by the
161 shell (so, for example, setting this to `foo --option=bar` will execute
162 `git credential-foo --option=bar` via the shell. See the manual of
163 specific helpers for examples of their use.
165 If there are multiple instances of the `credential.helper` configuration
166 variable, each helper will be tried in turn, and may provide a username,
167 password, or nothing. Once Git has acquired both a username and a
168 password, no more helpers will be tried.
170 If `credential.helper` is configured to the empty string, this resets
171 the helper list to empty (so you may override a helper set by a
172 lower-priority config file by configuring the empty-string helper,
173 followed by whatever set of helpers you would like).
177 A default username, if one is not provided in the URL.
181 By default, Git does not consider the "path" component of an http URL
182 to be worth matching via external helpers. This means that a credential
183 stored for `https://example.com/foo.git` will also be used for
184 `https://example.com/bar.git`. If you do want to distinguish these
185 cases, set this option to `true`.
191 You can write your own custom helpers to interface with any system in
192 which you keep credentials.
194 Credential helpers are programs executed by Git to fetch or save
195 credentials from and to long-term storage (where "long-term" is simply
196 longer than a single Git process; e.g., credentials may be stored
197 in-memory for a few minutes, or indefinitely on disk).
199 Each helper is specified by a single string in the configuration
200 variable `credential.helper` (and others, see linkgit:git-config[1]).
201 The string is transformed by Git into a command to be executed using
204 1. If the helper string begins with "!", it is considered a shell
205 snippet, and everything after the "!" becomes the command.
207 2. Otherwise, if the helper string begins with an absolute path, the
208 verbatim helper string becomes the command.
210 3. Otherwise, the string "git credential-" is prepended to the helper
211 string, and the result becomes the command.
213 The resulting command then has an "operation" argument appended to it
214 (see below for details), and the result is executed by the shell.
216 Here are some example specifications:
218 ----------------------------------------------------
219 # run "git credential-foo"
223 # same as above, but pass an argument to the helper
225 helper = "foo --bar=baz"
227 # the arguments are parsed by the shell, so use shell
228 # quoting if necessary
230 helper = "foo --bar='whitespace arg'"
232 # you can also use an absolute path, which will not use the git wrapper
234 helper = "/path/to/my/helper --with-arguments"
236 # or you can specify your own shell snippet
237 [credential "https://example.com"]
239 helper = "!f() { test \"$1\" = get && echo \"password=$(cat $HOME/.secret)\"; }; f"
240 ----------------------------------------------------
242 Generally speaking, rule (3) above is the simplest for users to specify.
243 Authors of credential helpers should make an effort to assist their
244 users by naming their program "git-credential-$NAME", and putting it in
245 the `$PATH` or `$GIT_EXEC_PATH` during installation, which will allow a
246 user to enable it with `git config credential.helper $NAME`.
248 When a helper is executed, it will have one "operation" argument
249 appended to its command line, which is one of:
253 Return a matching credential, if any exists.
257 Store the credential, if applicable to the helper.
261 Remove a matching credential, if any, from the helper's storage.
263 The details of the credential will be provided on the helper's stdin
264 stream. The exact format is the same as the input/output format of the
265 `git credential` plumbing command (see the section `INPUT/OUTPUT
266 FORMAT` in linkgit:git-credential[1] for a detailed specification).
268 For a `get` operation, the helper should produce a list of attributes on
269 stdout in the same format (see linkgit:git-credential[1] for common
270 attributes). A helper is free to produce a subset, or even no values at
271 all if it has nothing useful to provide. Any provided attributes will
272 overwrite those already known about by Git's credential subsystem.
274 While it is possible to override all attributes, well behaving helpers
275 should refrain from doing so for any attribute other than username and
278 If a helper outputs a `quit` attribute with a value of `true` or `1`,
279 no further helpers will be consulted, nor will the user be prompted
280 (if no credential has been provided, the operation will then fail).
282 Similarly, no more helpers will be consulted once both username and
283 password had been provided.
285 For a `store` or `erase` operation, the helper's output is ignored.
287 If a helper fails to perform the requested operation or needs to notify
288 the user of a potential issue, it may write to stderr.
290 If it does not support the requested operation (e.g., a read-only store),
291 it should silently ignore the request.
293 If a helper receives any other operation, it should silently ignore the
294 request. This leaves room for future operations to be added (older
295 helpers will just ignore the new requests).
299 Part of the linkgit:git[1] suite