From a6fc9fd3f4b42cd97b5262026e18bd451c28ee3c Mon Sep 17 00:00:00 2001 From: Jeff King Date: Sat, 10 Dec 2011 05:31:38 -0500 Subject: docs: end-user documentation for the credential subsystem The credential API and helper format is already defined in technical/api-credentials.txt. This presents the end-user view. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano diff --git a/Documentation/Makefile b/Documentation/Makefile index 304b31e..116f175 100644 --- a/Documentation/Makefile +++ b/Documentation/Makefile @@ -7,6 +7,7 @@ MAN5_TXT=gitattributes.txt gitignore.txt gitmodules.txt githooks.txt \ MAN7_TXT=gitcli.txt gittutorial.txt gittutorial-2.txt \ gitcvs-migration.txt gitcore-tutorial.txt gitglossary.txt \ gitdiffcore.txt gitnamespaces.txt gitrevisions.txt gitworkflows.txt +MAN7_TXT += gitcredentials.txt MAN_TXT = $(MAN1_TXT) $(MAN5_TXT) $(MAN7_TXT) MAN_XML=$(patsubst %.txt,%.xml,$(MAN_TXT)) diff --git a/Documentation/config.txt b/Documentation/config.txt index 5a841da..36bcdf2 100644 --- a/Documentation/config.txt +++ b/Documentation/config.txt @@ -832,6 +832,29 @@ commit.template:: "{tilde}/" is expanded to the value of `$HOME` and "{tilde}user/" to the specified user's home directory. +credential.helper:: + Specify an external helper to be called when a username or + password credential is needed; the helper may consult external + storage to avoid prompting the user for the credentials. See + linkgit:gitcredentials[7] for details. + +credential.useHttpPath:: + When acquiring credentials, consider the "path" component of an http + or https URL to be important. Defaults to false. See + linkgit:gitcredentials[7] for more information. + +credential.username:: + If no username is set for a network authentication, use this username + by default. See credential..* below, and + linkgit:gitcredentials[7]. + +credential..*:: + Any of the credential.* options above can be applied selectively to + some credentials. For example "credential.https://example.com.username" + would set the default username only for https connections to + example.com. See linkgit:gitcredentials[7] for details on how URLs are + matched. + include::diff-config.txt[] difftool..path:: diff --git a/Documentation/gitcredentials.txt b/Documentation/gitcredentials.txt new file mode 100644 index 0000000..07f6596 --- /dev/null +++ b/Documentation/gitcredentials.txt @@ -0,0 +1,171 @@ +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 does not yet +include any credential helpers, but you may 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 +------------------------------------------- + +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. + + +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. + + +CONFIGURATION OPTIONS +--------------------- + +Options for a credential context can be configured either in +`credential.\*` (which applies to all credentials), or +`credential..\*`, where 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. + +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 -- cgit v0.10.2-6-g49f6