git/Documentation/config/transfer.txt

transfer.credentialsInUrl::
	A configured URL can contain plaintext credentials in the form
	`<protocol>://<user>:<password>@<domain>/<path>`. You may want
	to warn or forbid the use of such configuration (in favor of
	using linkgit:git-credential[1]). This will be used on
	linkgit:git-clone[1], linkgit:git-fetch[1], linkgit:git-push[1],
	and any other direct use of the configured URL.
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Note that this is currently limited to detecting credentials in
`remote.<name>.url` configuration, it won't detect credentials in
`remote.<name>.pushurl` configuration.
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You might want to enable this to prevent inadvertent credentials
exposure, e.g. because:
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* The OS or system where you're running git may not provide a way or
  otherwise allow you to configure the permissions of the
  configuration file where the username and/or password are stored.
* Even if it does, having such data stored "at rest" might expose you
  in other ways, e.g. a backup process might copy the data to another
  system.
* The git programs will pass the full URL to one another as arguments
  on the command-line, meaning the credentials will be exposed to other
  users on OS's or systems that allow other users to see the full
  process list of other users. On linux the "hidepid" setting
  documented in procfs(5) allows for configuring this behavior.
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If such concerns don't apply to you then you probably don't need to be
concerned about credentials exposure due to storing that sensitive
data in git's configuration files. If you do want to use this, set
`transfer.credentialsInUrl` to one of these values:
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* `allow` (default): Git will proceed with its activity without warning.
* `warn`: Git will write a warning message to `stderr` when parsing a URL
  with a plaintext credential.
* `die`: Git will write a failure message to `stderr` when parsing a URL
  with a plaintext credential.

transfer.fsckObjects::
	When `fetch.fsckObjects` or `receive.fsckObjects` are
	not set, the value of this variable is used instead.
	Defaults to false.
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When set, the fetch or receive will abort in the case of a malformed
object or a link to a nonexistent object. In addition, various other
issues are checked for, including legacy issues (see `fsck.<msg-id>`),
and potential security issues like the existence of a `.GIT` directory
or a malicious `.gitmodules` file (see the release notes for v2.2.1
and v2.17.1 for details). Other sanity and security checks may be
added in future releases.
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On the receiving side, failing fsckObjects will make those objects
unreachable, see "QUARANTINE ENVIRONMENT" in
linkgit:git-receive-pack[1]. On the fetch side, malformed objects will
instead be left unreferenced in the repository.
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Due to the non-quarantine nature of the `fetch.fsckObjects`
implementation it cannot be relied upon to leave the object store
clean like `receive.fsckObjects` can.
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As objects are unpacked they're written to the object store, so there
can be cases where malicious objects get introduced even though the
"fetch" failed, only to have a subsequent "fetch" succeed because only
new incoming objects are checked, not those that have already been
written to the object store. That difference in behavior should not be
relied upon. In the future, such objects may be quarantined for
"fetch" as well.
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For now, the paranoid need to find some way to emulate the quarantine
environment if they'd like the same protection as "push". E.g. in the
case of an internal mirror do the mirroring in two steps, one to fetch
the untrusted objects, and then do a second "push" (which will use the
quarantine) to another internal repo, and have internal clients
consume this pushed-to repository, or embargo internal fetches and
only allow them once a full "fsck" has run (and no new fetches have
happened in the meantime).

transfer.hideRefs::
	String(s) `receive-pack` and `upload-pack` use to decide which
	refs to omit from their initial advertisements.  Use more than
	one definition to specify multiple prefix strings. A ref that is
	under the hierarchies listed in the value of this variable is
	excluded, and is hidden when responding to `git push` or `git
	fetch`.  See `receive.hideRefs` and `uploadpack.hideRefs` for
	program-specific versions of this config.
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You may also include a `!` in front of the ref name to negate the entry,
explicitly exposing it, even if an earlier entry marked it as hidden.
If you have multiple hideRefs values, later entries override earlier ones
(and entries in more-specific config files override less-specific ones).
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If a namespace is in use, the namespace prefix is stripped from each
reference before it is matched against `transfer.hiderefs` patterns. In
order to match refs before stripping, add a `^` in front of the ref name. If
you combine `!` and `^`, `!` must be specified first.
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For example, if `refs/heads/master` is specified in `transfer.hideRefs` and
the current namespace is `foo`, then `refs/namespaces/foo/refs/heads/master`
is omitted from the advertisements. If `uploadpack.allowRefInWant` is set,
`upload-pack` will treat `want-ref refs/heads/master` in a protocol v2
`fetch` command as if `refs/namespaces/foo/refs/heads/master` did not exist.
`receive-pack`, on the other hand, will still advertise the object id the
ref is pointing to without mentioning its name (a so-called ".have" line).
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Even if you hide refs, a client may still be able to steal the target
objects via the techniques described in the "SECURITY" section of the
linkgit:gitnamespaces[7] man page; it's best to keep private data in a
separate repository.

transfer.unpackLimit::
	When `fetch.unpackLimit` or `receive.unpackLimit` are
	not set, the value of this variable is used instead.
	The default value is 100.

transfer.advertiseSID::
	Boolean. When true, client and server processes will advertise their
	unique session IDs to their remote counterpart. Defaults to false.