@@ -13,7 +13,7 @@ SYNOPSIS
[--exec-path[=<path>]] [--html-path] [--man-path] [--info-path]
[-p|--paginate|-P|--no-pager] [--no-replace-objects] [--bare]
[--git-dir=<path>] [--work-tree=<path>] [--namespace=<name>]
- [--super-prefix=<path>]
+ [--super-prefix=<path>] [--config-env <name>=<envvar>]
<command> [<args>]
DESCRIPTION
@@ -80,6 +80,27 @@ config file). Including the equals but with an empty value (like `git -c
foo.bar= ...`) sets `foo.bar` to the empty string which `git config
--type=bool` will convert to `false`.
+--config-env=<name>=<envvar>::
+ Like `-c <name>=<var>` except the value is the name of an
+ environment variable from which to retrieve the value. Unlike
+ `-c` there is no shortcut for directly setting the value to an
+ empty string, instead the environment variable itself must be
+ set to the empty strin. Errors if the `<envvar>` does not exist
+ in the environment. `<envvar>` may not contain an equals sign
+ to avoid ambiguity with `<name>`s which contain one.
+
+ This is useful for cases where you want to pass transitory
+ configuration options to git, but are doing so on OS's where
+ other processes might be able to read your cmdline
+ (e.g. `/proc/self/cmdline`), but not your environ
+ (e.g. `/proc/self/environ`). That behavior is the default on
+ Linux, but may not be on your system.
+
+ Note that this might add security for variables such as
+ `http.extraHeader` where the sensitive information is part of
+ the value, but not e.g. `url.<base.insteadOf` where the
+ sensitive information can be part of the key.
+
--exec-path[=<path>]::
Path to wherever your core Git programs are installed.
This can also be controlled by setting the GIT_EXEC_PATH
@@ -345,6 +345,27 @@ void git_config_push_parameter(const char *text)
strbuf_release(&env);
}
+void git_config_push_env(const char *spec)
+{
+ struct strbuf buf = STRBUF_INIT;
+ const char *env_name;
+ const char *env_value;
+
+ env_name = strrchr(spec, '=');
+ if (!env_name)
+ die("invalid config format: %s", spec);
+ env_name++;
+
+ env_value = getenv(env_name);
+ if (!env_value)
+ die("config variable missing for '%s'", env_name);
+
+ strbuf_add(&buf, spec, env_name - spec);
+ strbuf_addstr(&buf, env_value);
+ git_config_push_parameter(buf.buf);
+ strbuf_release(&buf);
+}
+
static inline int iskeychar(int c)
{
return isalnum(c) || c == '-';
@@ -138,6 +138,7 @@ int git_config_from_mem(config_fn_t fn,
int git_config_from_blob_oid(config_fn_t fn, const char *name,
const struct object_id *oid, void *data);
void git_config_push_parameter(const char *text);
+void git_config_push_env(const char *spec);
int git_config_from_parameters(config_fn_t fn, void *data);
void read_early_config(config_fn_t cb, void *data);
void read_very_early_config(config_fn_t cb, void *data);
@@ -29,7 +29,7 @@ const char git_usage_string[] =
" [--exec-path[=<path>]] [--html-path] [--man-path] [--info-path]\n"
" [-p | --paginate | -P | --no-pager] [--no-replace-objects] [--bare]\n"
" [--git-dir=<path>] [--work-tree=<path>] [--namespace=<name>]\n"
- " [--super-prefix=<path>]\n"
+ " [--super-prefix=<path>] [--config-env=<name>=<envvar>]\n"
" <command> [<args>]");
const char git_more_info_string[] =
@@ -255,6 +255,8 @@ static int handle_options(const char ***argv, int *argc, int *envchanged)
git_config_push_parameter((*argv)[1]);
(*argv)++;
(*argc)--;
+ } else if (skip_prefix(cmd, "--config-env=", &cmd)) {
+ git_config_push_env(cmd);
} else if (!strcmp(cmd, "--literal-pathspecs")) {
setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "1", 1);
if (envchanged)
@@ -1316,6 +1316,51 @@ test_expect_success 'detect bogus GIT_CONFIG_PARAMETERS' '
git config --get-regexp "env.*"
'
+test_expect_success 'git --config-env=key=envvar support' '
+ cat >expect <<-\EOF &&
+ value
+ value
+ false
+ EOF
+ {
+ env ENVVAR=value git --config-env=core.name=ENVVAR config core.name &&
+ env ENVVAR=value git --config-env=foo.CamelCase=ENVVAR config foo.camelcase &&
+ env ENVVAR= git --config-env=foo.flag=ENVVAR config --bool foo.flag
+ } >actual &&
+ test_cmp expect actual
+'
+
+test_expect_success 'git --config-env fails with invalid parameters' '
+ test_must_fail git --config-env=foo.flag config --bool foo.flag 2>error &&
+ test_i18ngrep "invalid config format" error &&
+ test_must_fail git --config-env=foo.flag=NONEXISTENT config --bool foo.flag 2>error &&
+ test_i18ngrep "config variable missing" error
+'
+
+test_expect_success 'git -c and --config-env work together' '
+ cat >expect <<-\EOF &&
+ bar.cmd cmd-value
+ bar.env env-value
+ EOF
+ env ENVVAR=env-value git \
+ -c bar.cmd=cmd-value \
+ --config-env=bar.env=ENVVAR \
+ config --get-regexp "^bar.*" >actual &&
+ test_cmp expect actual
+'
+
+test_expect_success 'git -c and --config-env override each other' '
+ cat >expect <<-\EOF &&
+ env
+ cmd
+ EOF
+ {
+ env ENVVAR=env git -c bar.bar=cmd --config-env=bar.bar=ENVVAR config bar.bar &&
+ env ENVVAR=env git --config-env=bar.bar=ENVVAR -c bar.bar=cmd config bar.bar
+ } >actual &&
+ test_cmp expect actual
+'
+
test_expect_success 'git config --edit works' '
git config -f tmp test.value no &&
echo test.value=yes >expect &&
While it's already possible to pass runtime configuration via `git -c <key>=<value>`, it may be undesirable to use when the value contains sensitive information. E.g. if one wants to set `http.extraHeader` to contain an authentication token, doing so via `-c` would trivially leak those credentials via e.g. ps(1), which typically also shows command arguments. To enable this usecase without leaking credentials, this commit introduces a new switch `--config-env=<key>=<envvar>`. Instead of directly passing a value for the given key, it instead allows the user to specify the name of an environment variable. The value of that variable will then be used as value of the key. Co-authored-by: Jeff King <peff@peff.net> Signed-off-by: Patrick Steinhardt <ps@pks.im> --- Documentation/git.txt | 23 +++++++++++++++++++++- config.c | 21 ++++++++++++++++++++ config.h | 1 + git.c | 4 +++- t/t1300-config.sh | 45 +++++++++++++++++++++++++++++++++++++++++++ 5 files changed, 92 insertions(+), 2 deletions(-)