From b676388018a6c9a92310a152d03fa612201e8205 Mon Sep 17 00:00:00 2001
From: Lorenz Stechauner <lorenz.stechauner@necronda.net>
Date: Fri, 8 Jan 2021 18:01:19 +0100
Subject: [PATCH] Bugfix for proxy

---
 src/http.c      |  3 ++-
 src/rev_proxy.c | 31 +++++++++++++++++++++----------
 src/sock.c      |  7 ++++++-
 src/sock.h      |  4 ++++
 4 files changed, 33 insertions(+), 12 deletions(-)

diff --git a/src/http.c b/src/http.c
index 5e11cd3..b70a3fd 100644
--- a/src/http.c
+++ b/src/http.c
@@ -238,7 +238,8 @@ int http_send_request(sock *server, http_req *req) {
         off += sprintf(buf + off, "%s: %s\r\n", req->hdr.fields[i][0], req->hdr.fields[i][1]);
     }
     off += sprintf(buf + off, "\r\n");
-    if (sock_send(server, buf, off, 0) <= 0) {
+    long ret = sock_send(server, buf, off, 0);
+    if (ret <= 0) {
         return -1;
     }
     return 0;
diff --git a/src/rev_proxy.c b/src/rev_proxy.c
index 0444bbf..bc46c61 100644
--- a/src/rev_proxy.c
+++ b/src/rev_proxy.c
@@ -19,9 +19,11 @@ int rev_proxy_init(http_req *req, http_res *res, host_config *conf, sock *client
     int tries = 0;
     int retry = 0;
 
-    if (rev_proxy.socket != 0 && rev_proxy_host == conf->name) {
+    if (rev_proxy.socket != 0 && strcmp(rev_proxy_host, conf->name) == 0 && sock_check(&rev_proxy) == 0) {
         goto rev_proxy;
-    } else if (rev_proxy.socket != 0) {
+    }
+
+    if (rev_proxy.socket != 0) {
         sock_close(&rev_proxy);
     }
 
@@ -95,14 +97,13 @@ int rev_proxy_init(http_req *req, http_res *res, host_config *conf, sock *client
     print(BLUE_STR "Established new connection with " BLD_STR "[%s]:%i" CLR_STR, buffer, conf->rev_proxy.port);
 
     rev_proxy:
-    // TODO strange behaviour with Edge
     http_remove_header_field(&req->hdr, "Connection", HTTP_REMOVE_ALL);
     http_add_header_field(&req->hdr, "Connection", "keep-alive");
 
     ret = http_send_request(&rev_proxy, req);
     if (ret < 0) {
         res->status = http_get_status(502);
-        print(ERR_STR "Unable to send request to server: %s" CLR_STR, sock_strerror(&rev_proxy));
+        print(ERR_STR "Unable to send request to server (1): %s" CLR_STR, sock_strerror(&rev_proxy));
         sprintf(err_msg, "Unable to send request to server: %s.", sock_strerror(&rev_proxy));
         retry = tries < 4;
         goto proxy_err;
@@ -119,7 +120,7 @@ int rev_proxy_init(http_req *req, http_res *res, host_config *conf, sock *client
             ret = sock_send(&rev_proxy, client->buf, len, 0);
             if (ret <= 0) {
                 res->status = http_get_status(502);
-                print(ERR_STR "Unable to send request to server: %s" CLR_STR, sock_strerror(&rev_proxy));
+                print(ERR_STR "Unable to send request to server (2): %s" CLR_STR, sock_strerror(&rev_proxy));
                 sprintf(err_msg, "Unable to send request to server: %s.", sock_strerror(&rev_proxy));
                 retry = tries < 4;
                 goto proxy_err;
@@ -129,11 +130,21 @@ int rev_proxy_init(http_req *req, http_res *res, host_config *conf, sock *client
         if (content_len > 0) {
             ret = sock_splice(&rev_proxy, client, buffer, sizeof(buffer), content_len);
             if (ret <= 0) {
-                res->status = http_get_status(502);
-                print(ERR_STR "Unable to send request to server: %s" CLR_STR, sock_strerror(&rev_proxy));
-                sprintf(err_msg, "Unable to send request to server: %s.", sock_strerror(&rev_proxy));
-                retry = tries < 4;
-                goto proxy_err;
+                if (ret == -1) {
+                    res->status = http_get_status(502);
+                    print(ERR_STR "Unable to send request to server (3): %s" CLR_STR, sock_strerror(&rev_proxy));
+                    sprintf(err_msg, "Unable to send request to server: %s.", sock_strerror(&rev_proxy));
+                    retry = tries < 4;
+                    goto proxy_err;
+                } else if (ret == -2) {
+                    res->status = http_get_status(400);
+                    print(ERR_STR "Unable to receive request from client: %s" CLR_STR, sock_strerror(client));
+                    sprintf(err_msg, "Unable to receive request from client: %s.", sock_strerror(client));
+                    return -1;
+                }
+                res->status = http_get_status(500);
+                print(ERR_STR "Unknown Error" CLR_STR);
+                return -1;
             }
         }
     }
diff --git a/src/sock.c b/src/sock.c
index 4d090a4..649466c 100644
--- a/src/sock.c
+++ b/src/sock.c
@@ -78,7 +78,7 @@ long sock_splice(sock *dst, sock *src, void *buf, unsigned long buf_len, unsigne
     unsigned long send_len = 0;
     unsigned long next_len;
     while (send_len < len) {
-        next_len = buf_len < len - send_len ? buf_len : len - send_len;
+        next_len = (buf_len < (len - send_len)) ? buf_len : (len - send_len);
         ret = sock_recv(src, buf, next_len, 0);
         if (ret < 0) return -2;
         if (ret != next_len) return -3;
@@ -102,3 +102,8 @@ int sock_close(sock *s) {
     s->ssl = NULL;
     return 0;
 }
+
+int sock_check(sock *s) {
+    char buf;
+    return recv(s->socket, &buf, 1, MSG_PEEK | MSG_DONTWAIT) == 1;
+}
diff --git a/src/sock.h b/src/sock.h
index 5673dd5..543c7ac 100644
--- a/src/sock.h
+++ b/src/sock.h
@@ -29,4 +29,8 @@ long sock_recv(sock *s, void *buf, unsigned long len, int flags);
 
 long sock_splice(sock *dst, sock *src, void *buf, unsigned long buf_len, unsigned long len);
 
+int sock_close(sock *s);
+
+int sock_check(sock *s);
+
 #endif //NECRONDA_SERVER_SOCK_H