fix ssl shutdown management

plugins/corerouter/corerouter.c

@@ -65,6 +65,7 @@ void uwsgi_cr_peer_reset(struct corerouter_peer *peer) {
 		free(peer->tmp_socket_name);
 		peer->tmp_socket_name = NULL;
 	}
+
 	cr_del_timeout(peer->session->corerouter, peer);
 	
 	if (peer->fd != -1) {
@@ -84,7 +85,14 @@ void uwsgi_cr_peer_reset(struct corerouter_peer *peer) {
 }
 
 // destroy a peer
-void uwsgi_cr_peer_del(struct corerouter_peer *peer) {
+int uwsgi_cr_peer_del(struct corerouter_peer *peer) {
+	// first of all check if we need to run a flush procedure
+	if (peer->flush && !peer->is_flushing) {
+        	peer->is_flushing = 1;
+		// on success, suspend the execution
+		if (peer->flush(peer) >= 0) return -1;
+        }
+
 	struct corerouter_peer *prev = peer->prev;
 	struct corerouter_peer *next = peer->next;
 
@@ -115,6 +123,7 @@ void uwsgi_cr_peer_del(struct corerouter_peer *peer) {
 		free(peer->key);
 	}
 	free(peer);
+	return 0;
 }
 
 void uwsgi_opt_corerouter(char *opt, char *value, void *cr) {
@@ -397,7 +406,7 @@ void corerouter_close_peer(struct uwsgi_corerouter *ucr, struct corerouter_peer
 	}
 
 end:
-	uwsgi_cr_peer_del(peer);
+	if (uwsgi_cr_peer_del(peer) < 0) return;
 
 	if (peer == cs->main_peer) {
 		cs->main_peer = NULL;
@@ -415,7 +424,7 @@ void corerouter_close_session(struct uwsgi_corerouter *ucr, struct corerouter_se
 
 	struct corerouter_peer *main_peer = cr_session->main_peer;
 	if (main_peer) {
-		uwsgi_cr_peer_del(main_peer);
+		if (uwsgi_cr_peer_del(main_peer) < 0) return;
 	}
 
 	// free peers
@@ -427,7 +436,7 @@ void corerouter_close_session(struct uwsgi_corerouter *ucr, struct corerouter_se
 		if (ucr->subscriptions && tmp_peer->un && tmp_peer->un->len) {
 			tmp_peer->un->reference--;
 		}
-		uwsgi_cr_peer_del(tmp_peer);
+		if (uwsgi_cr_peer_del(tmp_peer) < 0) return; 
 	}
 
 	// could be used to free additional resources

plugins/corerouter/cr.h

@@ -195,6 +195,9 @@ struct corerouter_peer {
 	char proto;
 
 	int free_key;
+
+	ssize_t (*flush)(struct corerouter_peer *);
+        int is_flushing;
 };
 
 struct uwsgi_corerouter {

plugins/http/https.c

@@ -374,6 +374,47 @@ ssize_t hr_ssl_read(struct corerouter_peer *main_peer) {
         return -1;
 }
 
+ssize_t hr_ssl_shutdown(struct corerouter_peer *peer) {
+	// ensure no hooks are set
+	if (uwsgi_cr_set_hooks(peer, NULL, NULL)) return -1;
+
+	struct corerouter_session *cs = peer->session;
+        struct http_session *hr = (struct http_session *) cs;	
+
+	int ret = SSL_shutdown(hr->ssl);
+	if (ret < 0) return -1;
+	if (ret == 1) return 0;
+
+	int err = 0;
+
+	if (ERR_peek_error()) {
+		err = SSL_get_error(hr->ssl, ret);
+	}
+
+	// no error, close the connection
+	if (err == 0 || err == SSL_ERROR_ZERO_RETURN) return -1;
+
+	if (err == SSL_ERROR_WANT_READ) {
+		if (uwsgi_cr_set_hooks(peer, hr_ssl_shutdown, NULL)) return -1;
+                return 1;
+        }
+
+        else if (err == SSL_ERROR_WANT_WRITE) {
+		if (uwsgi_cr_set_hooks(peer, NULL, hr_ssl_shutdown)) return -1;
+                return 1;
+        }
+
+        else if (err == SSL_ERROR_SYSCALL) {
+                uwsgi_cr_error(peer, "hr_ssl_shutdown()");
+        }
+
+        else if (err == SSL_ERROR_SSL && uwsgi.ssl_verbose) {
+                ERR_print_errors_fp(stderr);
+        }
+
+        return -1;
+}
+
 void hr_setup_ssl(struct http_session *hr, struct uwsgi_gateway_socket *ugs) {
  	hr->ssl = SSL_new(ugs->ctx);
         SSL_set_fd(hr->ssl, hr->session.main_peer->fd);
@@ -382,6 +423,7 @@ void hr_setup_ssl(struct http_session *hr, struct uwsgi_gateway_socket *ugs) {
         SSL_set_ex_data(hr->ssl, uhttp.spdy_index, hr);
 #endif
         uwsgi_cr_set_hooks(hr->session.main_peer, hr_ssl_read, NULL);
+	hr->session.main_peer->flush = hr_ssl_shutdown;
         hr->session.close = hr_session_ssl_close;
 	hr->func_write = hr_ssl_write;
 }