static int auto_update_server_info;
static int auto_gc = 1;
static int fix_thin = 1;
+static int stateless_rpc;
+static const char *service_dir;
static const char *head_name;
static void *head_name_to_free;
static int sent_capabilities;
static const char *NONCE_BAD = "BAD";
static const char *NONCE_MISSING = "MISSING";
static const char *NONCE_OK = "OK";
+static const char *NONCE_SLOP = "SLOP";
static const char *nonce_status;
+static long nonce_stamp_slop;
+static unsigned long nonce_stamp_slop_limit;
static enum deny_action parse_deny_action(const char *var, const char *value)
{
if (strcmp(var, "receive.certnonceseed") == 0)
return git_config_string(&cert_nonce_seed, var, value);
+ if (strcmp(var, "receive.certnonceslop") == 0) {
+ nonce_stamp_slop_limit = git_config_ulong(var, value);
+ return 0;
+ }
+
return git_default_config(var, value, cb);
}
static const char *check_nonce(const char *buf, size_t len)
{
char *nonce = find_header(buf, len, "nonce");
+ unsigned long stamp, ostamp;
+ char *bohmac, *expect = NULL;
const char *retval = NONCE_BAD;
if (!nonce) {
goto leave;
}
- /* returned nonce MUST match what we gave out earlier */
- retval = NONCE_BAD;
+ if (!stateless_rpc) {
+ /* returned nonce MUST match what we gave out earlier */
+ retval = NONCE_BAD;
+ goto leave;
+ }
+
+ /*
+ * In stateless mode, we may be receiving a nonce issued by
+ * another instance of the server that serving the same
+ * repository, and the timestamps may not match, but the
+ * nonce-seed and dir should match, so we can recompute and
+ * report the time slop.
+ *
+ * In addition, when a nonce issued by another instance has
+ * timestamp within receive.certnonceslop seconds, we pretend
+ * as if we issued that nonce when reporting to the hook.
+ */
+
+ /* nonce is concat(<seconds-since-epoch>, "-", <hmac>) */
+ if (*nonce <= '0' || '9' < *nonce) {
+ retval = NONCE_BAD;
+ goto leave;
+ }
+ stamp = strtoul(nonce, &bohmac, 10);
+ if (bohmac == nonce || bohmac[0] != '-') {
+ retval = NONCE_BAD;
+ goto leave;
+ }
+
+ expect = prepare_push_cert_nonce(service_dir, stamp);
+ if (strcmp(expect, nonce)) {
+ /* Not what we would have signed earlier */
+ retval = NONCE_BAD;
+ goto leave;
+ }
+
+ /*
+ * By how many seconds is this nonce stale? Negative value
+ * would mean it was issued by another server with its clock
+ * skewed in the future.
+ */
+ ostamp = strtoul(push_cert_nonce, NULL, 10);
+ nonce_stamp_slop = (long)ostamp - (long)stamp;
+
+ if (nonce_stamp_slop_limit &&
+ abs(nonce_stamp_slop) <= nonce_stamp_slop_limit) {
+ /*
+ * Pretend as if the received nonce (which passes the
+ * HMAC check, so it is not a forged by third-party)
+ * is what we issued.
+ */
+ free((void *)push_cert_nonce);
+ push_cert_nonce = xstrdup(nonce);
+ retval = NONCE_OK;
+ } else {
+ retval = NONCE_SLOP;
+ }
leave:
free(nonce);
+ free(expect);
return retval;
}
if (push_cert_nonce) {
argv_array_pushf(&env, "GIT_PUSH_CERT_NONCE=%s", push_cert_nonce);
argv_array_pushf(&env, "GIT_PUSH_CERT_NONCE_STATUS=%s", nonce_status);
+ if (nonce_status == NONCE_SLOP)
+ argv_array_pushf(&env, "GIT_PUSH_CERT_NONCE_SLOP=%ld",
+ nonce_stamp_slop);
}
proc->env = env.argv;
}
int cmd_receive_pack(int argc, const char **argv, const char *prefix)
{
int advertise_refs = 0;
- int stateless_rpc = 0;
int i;
- const char *dir = NULL;
struct command *commands;
struct sha1_array shallow = SHA1_ARRAY_INIT;
struct sha1_array ref = SHA1_ARRAY_INIT;
usage(receive_pack_usage);
}
- if (dir)
+ if (service_dir)
usage(receive_pack_usage);
- dir = arg;
+ service_dir = arg;
}
- if (!dir)
+ if (!service_dir)
usage(receive_pack_usage);
setup_path();
- if (!enter_repo(dir, 0))
- die("'%s' does not appear to be a git repository", dir);
+ if (!enter_repo(service_dir, 0))
+ die("'%s' does not appear to be a git repository", service_dir);
git_config(receive_pack_config, NULL);
if (cert_nonce_seed)
- push_cert_nonce = prepare_push_cert_nonce(dir, time(NULL));
+ push_cert_nonce = prepare_push_cert_nonce(service_dir, time(NULL));
if (0 <= transfer_unpack_limit)
unpack_limit = transfer_unpack_limit;