daemon: give friendlier error messages to clients
When the git-daemon is asked about an inaccessible repository, it simply hangs up the connection without saying anything further. This makes it hard to distinguish between a repository we cannot access (e.g., due to typo), and a service or network outage. Instead, let's print an "ERR" line, which git clients understand since v1.6.1 (2008-12-24). Because there is a risk of leaking information about non-exported repositories, by default all errors simply say "access denied or repository not exported". Sites which don't have hidden repositories, or don't care, can pass a flag to turn on more specific messages. Signed-off-by: Jeff King <peff@peff.net> Helped-by: Sitaram Chamarty <sitaramc@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jeff King committed
Oct 14, 2011 at 17:19 UTC
d5570f4d2cb29f3db9f69ff5fcde0a7d54ad2696
2 files changed
+31
-4
Documentation/git-daemon.txt
+10
@@ -161,6 +161,16 @@ the facility of inet daemon to achieve the same before spawning
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repository configuration. By default, all the services
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are overridable.
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+--informative-errors::
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+--no-informative-errors::
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+ When informative errors are turned on, git-daemon will report
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+ more verbose errors to the client, differentiating conditions
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+ like "no such repository" from "repository not exported". This
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+ is more convenient for clients, but may leak information about
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+ the existence of unexported repositories. When informative
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+ errors are not enabled, all errors report "access denied" to the
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+ client. The default is --no-informative-errors.
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+
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<directory>::
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A directory to add to the whitelist of allowed directories. Unless
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--strict-paths is specified this will also include subdirectories
daemon.c
+21
-4
@@ -20,6 +20,7 @@
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static int log_syslog;
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static int verbose;
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static int reuseaddr;
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+static int informative_errors;
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static const char daemon_usage[] =
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"git daemon [--verbose] [--syslog] [--export-all]\n"
@@ -247,6 +248,14 @@ static int git_daemon_config(const char *var, const char *value, void *cb)
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return 0;
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}
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+static int daemon_error(const char *dir, const char *msg)
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+{
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+ if (!informative_errors)
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+ msg = "access denied or repository not exported";
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+ packet_write(1, "ERR %s: %s", msg, dir);
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+ return -1;
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+}
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+
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static int run_service(char *dir, struct daemon_service *service)
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{
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const char *path;
@@ -257,11 +266,11 @@ static int run_service(char *dir, struct daemon_service *service)
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if (!enabled && !service->overridable) {
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logerror("'%s': service not enabled.", service->name);
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errno = EACCES;
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- return -1;
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+ return daemon_error(dir, "service not enabled");
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}
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if (!(path = path_ok(dir)))
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- return -1;
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+ return daemon_error(dir, "no such repository");
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/*
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* Security on the cheap.
@@ -277,7 +286,7 @@ static int run_service(char *dir, struct daemon_service *service)
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if (!export_all_trees && access("git-daemon-export-ok", F_OK)) {
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logerror("'%s': repository not exported.", path);
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errno = EACCES;
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- return -1;
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+ return daemon_error(dir, "repository not exported");
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}
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if (service->overridable) {
@@ -291,7 +300,7 @@ static int run_service(char *dir, struct daemon_service *service)
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logerror("'%s': service not enabled for '%s'",
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service->name, path);
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errno = EACCES;
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- return -1;
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+ return daemon_error(dir, "service not enabled");
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}
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/*
@@ -1167,6 +1176,14 @@ int main(int argc, char **argv)
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make_service_overridable(arg + 18, 0);
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continue;
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}
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+ if (!prefixcmp(arg, "--informative-errors")) {
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+ informative_errors = 1;
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+ continue;
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+ }
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+ if (!prefixcmp(arg, "--no-informative-errors")) {
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+ informative_errors = 0;
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+ continue;
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+ }
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if (!strcmp(arg, "--")) {
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ok_paths = &argv[i+1];
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break;