From ef3e8475fbc02c0a9d69b96da91d33afdd42f8ba Mon Sep 17 00:00:00 2001
From: Lorenz Stechauner <lorenz.stechauner@necronda.net>
Date: Fri, 7 Jul 2023 21:30:56 +0200
Subject: [PATCH] Honor Connection: closed received from reverse proxy peers

---
 src/lib/proxy.c | 12 ++++++++++--
 src/lib/proxy.h |  2 +-
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/src/lib/proxy.c b/src/lib/proxy.c
index 7d08ab7..0cc9350 100644
--- a/src/lib/proxy.c
+++ b/src/lib/proxy.c
@@ -139,6 +139,10 @@ proxy_ctx_t *proxy_get_by_conf(host_config_t *conf) {
 
 void proxy_unlock_ctx(proxy_ctx_t *ctx) {
     int n = (int) ((ctx - proxies) / MAX_PROXY_CNX_PER_HOST);
+    if (ctx->close) {
+        proxy_close(ctx);
+        ctx->close = 0;
+    }
     debug("Released proxy connection slot %i/%i", (ctx - proxies) % MAX_PROXY_CNX_PER_HOST, MAX_PROXY_CNX_PER_HOST);
     ctx->in_use = 0;
     ctx->client = NULL;
@@ -400,8 +404,9 @@ int proxy_init(proxy_ctx_t **proxy_ptr, http_req *req, http_res *res, http_statu
             return -1;
 
         // honor server timeout with one second buffer
-        if (!proxy->initialized || sock_has_pending(&proxy->proxy, SOCK_DONTWAIT) != 0 || srv_error ||
-           (proxy->http_timeout != 0 && (clock_micros() - proxy->proxy.ts_last_send) >= proxy->http_timeout - 1000000))
+        if (!proxy->initialized || srv_error ||
+            (proxy->http_timeout > 0 && (clock_micros() - proxy->proxy.ts_last_send) >= proxy->http_timeout) ||
+            sock_has_pending(&proxy->proxy, SOCK_DONTWAIT))
         {
             if (proxy->initialized)
                 proxy_close(proxy);
@@ -549,6 +554,9 @@ int proxy_init(proxy_ctx_t **proxy_ptr, http_req *req, http_res *res, http_statu
     long keep_alive_timeout = http_get_keep_alive_timeout(&res->hdr);
     proxy->http_timeout = (keep_alive_timeout > 0) ? keep_alive_timeout * 1000000 : 0;
 
+    connection = http_get_header_field(&res->hdr, "Connection");
+    proxy->close = !strcontains(connection, "keep-alive") && !strcontains(connection, "Keep-Alive");
+
     ret = proxy_response_header(req, res, conf);
     if (ret != 0) {
         res->status = http_get_status(500);
diff --git a/src/lib/proxy.h b/src/lib/proxy.h
index c7f1ade..be6f06f 100644
--- a/src/lib/proxy.h
+++ b/src/lib/proxy.h
@@ -19,7 +19,7 @@
 #include "config.h"
 
 typedef struct {
-    volatile unsigned char initialized:1, in_use:1;
+    volatile unsigned char initialized:1, in_use:1, close:1;
     sock proxy;
     long cnx_s, cnx_e;
     long http_timeout;