From c8bae7493d2f2910b57f13ded012e86bdcfb0532 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 16:47:53 +0200 Subject: Adding upstream version 1:2.39.2. Signed-off-by: Daniel Baumann --- builtin/credential-cache--daemon.c | 319 +++++++++++++++++++++++++++++++++++++ 1 file changed, 319 insertions(+) create mode 100644 builtin/credential-cache--daemon.c (limited to 'builtin/credential-cache--daemon.c') 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] ", + 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] ", + "", + "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 */ -- cgit v1.2.3