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authorJeff King <peff@peff.net>2020-08-13 14:58:55 (GMT)
committerJunio C Hamano <gitster@pobox.com>2020-08-13 18:02:08 (GMT)
commitb5dd96b70aca364f163f0b3743418779cfe062e6 (patch)
tree74ce93ebb5a91a27a746a1c4cb91277e1dd09184 /credential-cache--daemon.c
parenta04f6531099cabbbb94e3d7be0b3db0b718860ee (diff)
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make credential helpers builtins
There's no real reason for credential helpers to be separate binaries. I did them this way originally under the notion that helper don't _need_ to be part of Git, and so can be built totally separately (and indeed, the ones in contrib/credential are). But the ones in our main Makefile build on libgit.a, and the resulting binaries are reasonably large. We can slim down our total disk footprint by just making them builtins. This reduces the size of: make strip install from 29MB to 24MB on my Debian system. Note that credential-cache can't operate without support for Unix sockets. Currently we just don't build it at all when NO_UNIX_SOCKETS is set. We could continue that with conditionals in the Makefile and our list of builtins. But instead, let's build a dummy implementation that dies with an informative message. That has two advantages: - it's simpler, because the conditional bits are all kept inside the credential-cache source - a user who is expecting it to exist will be told _why_ they can't use it, rather than getting the "credential-cache is not a git command" error which makes it look like the Git install is broken. Note that our dummy implementation does still respond to "-h" in order to appease t0012 (and this may be a little friendlier for users, as well). Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Diffstat (limited to 'credential-cache--daemon.c')
-rw-r--r--credential-cache--daemon.c297
1 files changed, 0 insertions, 297 deletions
diff --git a/credential-cache--daemon.c b/credential-cache--daemon.c
deleted file mode 100644
index ec1271f..0000000
--- a/credential-cache--daemon.c
+++ /dev/null
@@ -1,297 +0,0 @@
-#include "cache.h"
-#include "config.h"
-#include "tempfile.h"
-#include "credential.h"
-#include "unix-socket.h"
-#include "parse-options.h"
-
-struct credential_cache_entry {
- struct credential item;
- timestamp_t expiration;
-};
-static struct credential_cache_entry *entries;
-static int entries_nr;
-static int entries_alloc;
-
-static void cache_credential(struct credential *c, int timeout)
-{
- struct credential_cache_entry *e;
-
- ALLOC_GROW(entries, entries_nr + 1, entries_alloc);
- e = &entries[entries_nr++];
-
- /* take ownership of pointers */
- memcpy(&e->item, c, sizeof(*c));
- memset(c, 0, sizeof(*c));
- e->expiration = time(NULL) + timeout;
-}
-
-static struct credential_cache_entry *lookup_credential(const struct credential *c)
-{
- int i;
- for (i = 0; i < entries_nr; i++) {
- struct credential *e = &entries[i].item;
- if (credential_match(c, e))
- return &entries[i];
- }
- return NULL;
-}
-
-static void remove_credential(const struct credential *c)
-{
- struct credential_cache_entry *e;
-
- e = lookup_credential(c);
- if (e)
- e->expiration = 0;
-}
-
-static timestamp_t check_expirations(void)
-{
- static timestamp_t wait_for_entry_until;
- int i = 0;
- timestamp_t now = time(NULL);
- timestamp_t next = TIME_MAX;
-
- /*
- * Initially give the client 30 seconds to actually contact us
- * and store a credential before we decide there's no point in
- * keeping the daemon around.
- */
- if (!wait_for_entry_until)
- wait_for_entry_until = now + 30;
-
- while (i < entries_nr) {
- if (entries[i].expiration <= now) {
- entries_nr--;
- credential_clear(&entries[i].item);
- if (i != entries_nr)
- memcpy(&entries[i], &entries[entries_nr], sizeof(*entries));
- /*
- * Stick around 30 seconds in case a new credential
- * shows up (e.g., because we just removed a failed
- * one, and we will soon get the correct one).
- */
- wait_for_entry_until = now + 30;
- }
- else {
- if (entries[i].expiration < next)
- next = entries[i].expiration;
- i++;
- }
- }
-
- if (!entries_nr) {
- if (wait_for_entry_until <= now)
- return 0;
- next = wait_for_entry_until;
- }
-
- return next - now;
-}
-
-static int read_request(FILE *fh, struct credential *c,
- struct strbuf *action, int *timeout)
-{
- static struct strbuf item = STRBUF_INIT;
- const char *p;
-
- strbuf_getline_lf(&item, fh);
- if (!skip_prefix(item.buf, "action=", &p))
- return error("client sent bogus action line: %s", item.buf);
- strbuf_addstr(action, p);
-
- strbuf_getline_lf(&item, fh);
- if (!skip_prefix(item.buf, "timeout=", &p))
- return error("client sent bogus timeout line: %s", item.buf);
- *timeout = atoi(p);
-
- if (credential_read(c, fh) < 0)
- return -1;
- return 0;
-}
-
-static void serve_one_client(FILE *in, FILE *out)
-{
- struct credential c = CREDENTIAL_INIT;
- struct strbuf action = STRBUF_INIT;
- int timeout = -1;
-
- if (read_request(in, &c, &action, &timeout) < 0)
- /* ignore error */ ;
- else if (!strcmp(action.buf, "get")) {
- struct credential_cache_entry *e = lookup_credential(&c);
- if (e) {
- fprintf(out, "username=%s\n", e->item.username);
- fprintf(out, "password=%s\n", e->item.password);
- }
- }
- else if (!strcmp(action.buf, "exit")) {
- /*
- * It's important that we clean up our socket first, and then
- * signal the client only once we have finished the cleanup.
- * Calling exit() directly does this, because we clean up in
- * our atexit() handler, and then signal the client when our
- * process actually ends, which closes the socket and gives
- * them EOF.
- */
- exit(0);
- }
- else if (!strcmp(action.buf, "erase"))
- remove_credential(&c);
- else if (!strcmp(action.buf, "store")) {
- if (timeout < 0)
- warning("cache client didn't specify a timeout");
- else if (!c.username || !c.password)
- warning("cache client gave us a partial credential");
- else {
- remove_credential(&c);
- cache_credential(&c, timeout);
- }
- }
- else
- warning("cache client sent unknown action: %s", action.buf);
-
- credential_clear(&c);
- strbuf_release(&action);
-}
-
-static int serve_cache_loop(int fd)
-{
- struct pollfd pfd;
- timestamp_t wakeup;
-
- wakeup = check_expirations();
- if (!wakeup)
- return 0;
-
- pfd.fd = fd;
- pfd.events = POLLIN;
- if (poll(&pfd, 1, 1000 * wakeup) < 0) {
- if (errno != EINTR)
- die_errno("poll failed");
- return 1;
- }
-
- if (pfd.revents & POLLIN) {
- int client, client2;
- FILE *in, *out;
-
- client = accept(fd, NULL, NULL);
- if (client < 0) {
- warning_errno("accept failed");
- return 1;
- }
- client2 = dup(client);
- if (client2 < 0) {
- warning_errno("dup failed");
- close(client);
- return 1;
- }
-
- in = xfdopen(client, "r");
- out = xfdopen(client2, "w");
- serve_one_client(in, out);
- fclose(in);
- fclose(out);
- }
- return 1;
-}
-
-static void serve_cache(const char *socket_path, int debug)
-{
- int fd;
-
- fd = unix_stream_listen(socket_path);
- if (fd < 0)
- die_errno("unable to bind to '%s'", socket_path);
-
- printf("ok\n");
- fclose(stdout);
- if (!debug) {
- if (!freopen("/dev/null", "w", stderr))
- die_errno("unable to point stderr to /dev/null");
- }
-
- while (serve_cache_loop(fd))
- ; /* nothing */
-
- close(fd);
-}
-
-static const char permissions_advice[] = N_(
-"The permissions on your socket directory are too loose; other\n"
-"users may be able to read your cached credentials. Consider running:\n"
-"\n"
-" chmod 0700 %s");
-static void init_socket_directory(const char *path)
-{
- struct stat st;
- char *path_copy = xstrdup(path);
- char *dir = dirname(path_copy);
-
- if (!stat(dir, &st)) {
- if (st.st_mode & 077)
- die(_(permissions_advice), dir);
- } else {
- /*
- * We must be sure to create the directory with the correct mode,
- * not just chmod it after the fact; otherwise, there is a race
- * condition in which somebody can chdir to it, sleep, then try to open
- * our protected socket.
- */
- if (safe_create_leading_directories_const(dir) < 0)
- die_errno("unable to create directories for '%s'", dir);
- if (mkdir(dir, 0700) < 0)
- die_errno("unable to mkdir '%s'", dir);
- }
-
- if (chdir(dir))
- /*
- * We don't actually care what our cwd is; we chdir here just to
- * be a friendly daemon and avoid tying up our original cwd.
- * If this fails, it's OK to just continue without that benefit.
- */
- ;
-
- free(path_copy);
-}
-
-int cmd_main(int argc, const char **argv)
-{
- struct tempfile *socket_file;
- const char *socket_path;
- int ignore_sighup = 0;
- static const char *usage[] = {
- "git-credential-cache--daemon [opts] <socket_path>",
- NULL
- };
- int debug = 0;
- const struct option options[] = {
- OPT_BOOL(0, "debug", &debug,
- N_("print debugging messages to stderr")),
- OPT_END()
- };
-
- git_config_get_bool("credentialcache.ignoresighup", &ignore_sighup);
-
- argc = parse_options(argc, argv, NULL, options, usage, 0);
- socket_path = argv[0];
-
- if (!socket_path)
- usage_with_options(usage, options);
-
- if (!is_absolute_path(socket_path))
- die("socket directory must be an absolute path");
-
- init_socket_directory(socket_path);
- socket_file = register_tempfile(socket_path);
-
- if (ignore_sighup)
- signal(SIGHUP, SIG_IGN);
-
- serve_cache(socket_path, debug);
- delete_tempfile(&socket_file);
-
- return 0;
-}