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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 14:47:53 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 14:47:53 +0000
commitc8bae7493d2f2910b57f13ded012e86bdcfb0532 (patch)
tree24e09d9f84dec336720cf393e156089ca2835791 /builtin/credential-cache--daemon.c
parentInitial commit. (diff)
downloadgit-c8bae7493d2f2910b57f13ded012e86bdcfb0532.tar.xz
git-c8bae7493d2f2910b57f13ded012e86bdcfb0532.zip
Adding upstream version 1:2.39.2.upstream/1%2.39.2upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'builtin/credential-cache--daemon.c')
-rw-r--r--builtin/credential-cache--daemon.c319
1 files changed, 319 insertions, 0 deletions
diff --git a/builtin/credential-cache--daemon.c b/builtin/credential-cache--daemon.c
new file mode 100644
index 0000000..f3c8983
--- /dev/null
+++ b/builtin/credential-cache--daemon.c
@@ -0,0 +1,319 @@
+#include "builtin.h"
+#include "parse-options.h"
+
+#ifndef NO_UNIX_SOCKETS
+
+#include "config.h"
+#include "tempfile.h"
+#include "credential.h"
+#include "unix-socket.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)
+{
+ struct unix_stream_listen_opts opts = UNIX_STREAM_LISTEN_OPTS_INIT;
+ int fd;
+
+ fd = unix_stream_listen(socket_path, &opts);
+ 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_credential_cache_daemon(int argc, const char **argv, const char *prefix)
+{
+ struct tempfile *socket_file;
+ const char *socket_path;
+ int ignore_sighup = 0;
+ static const char *usage[] = {
+ "git credential-cache--daemon [--debug] <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, prefix, 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;
+}
+
+#else
+
+int cmd_credential_cache_daemon(int argc, const char **argv, const char *prefix)
+{
+ const char * const usage[] = {
+ "git credential-cache--daemon [--debug] <socket-path>",
+ "",
+ "credential-cache--daemon is disabled in this build of Git",
+ NULL
+ };
+ struct option options[] = { OPT_END() };
+
+ argc = parse_options(argc, argv, prefix, options, usage, 0);
+ die(_("credential-cache--daemon unavailable; no unix socket support"));
+}
+
+#endif /* NO_UNIX_SOCKET */