BUG/MEDIUM: cache: Be sure to end the forwarding when XFER length is unknown

This bug exists in the HTX code and in the legacy one. When the body length is
unknown, the applet hangs. For the legacy code, it hangs because the end of the
cached object is not correctly handled and the applet is never recalled. For the
HTX code, only the begining of the response (the 1st buffer) is sent then the
applet hangs. To work in HTX, The fast forwarding must be correctly handled.

This patch must be backported to 1.9.

[cf: the patch adding the function channel_add_input must be backported with
this one. It does not exist in 1.8 because only responses with a C-L are cached.]

diff --git a/src/cache.c b/src/cache.c
index 020650a336307b2a13b7f42d109ab8d94a63c7c9..d80ee904f9c99d7b6825780275a484c201456d53 100644 (file)
--- a/src/cache.c
+++ b/src/cache.c
@@ -994,12 +994,13 @@ static void htx_cache_io_handler(struct appctx *appctx)
                unsigned int len = cache_ptr->hdrs_len + cache_ptr->data_len - appctx->ctx.cache.sent;
 
                ret = htx_cache_dump_data(appctx, res_htx, HTX_BLK_DATA, len);
-               if (!ret) {
+               total += ret;
+               res_htx->extra = (len - ret);
+               if (ret < len) {
                        si_rx_room_blk(si);
                        goto out;
                }
 
-               total += ret;
                if (cache_ptr->hdrs_len + cache_ptr->data_len == appctx->ctx.cache.sent) {
                        if (first->len > sizeof(*cache_ptr) + appctx->ctx.cache.sent) {
                                /* Headers and all data have been sent
@@ -1026,7 +1027,7 @@ static void htx_cache_io_handler(struct appctx *appctx)
                unsigned int len = first->len - sizeof(*cache_ptr) - appctx->ctx.cache.sent;
 
                ret = htx_cache_dump_data(appctx, res_htx, HTX_BLK_TLR, len);
-               if (!ret) {
+               if (ret < len) {
                        si_rx_room_blk(si);
                        goto out;
                }
@@ -1067,10 +1068,8 @@ static void htx_cache_io_handler(struct appctx *appctx)
                }
        }
   out:
-       if (total) {
-               res->total += total;
-               res->flags |= CF_READ_PARTIAL;
-       }
+       if (total)
+               channel_add_input(res, total);
 
        /* we have left the request in the buffer for the case where we
         * process a POST, and this automatically re-enables activity on
@@ -1196,7 +1195,6 @@ static void http_cache_io_handler(struct appctx *appctx)
        /* buffer are aligned there, should be fine */
        if (appctx->st0 == HTTP_CACHE_HEADER || appctx->st0 == HTTP_CACHE_INIT) {
                int len = first->len - *sent - sizeof(struct cache_entry);
-
                if (len > 0) {
                        int ret;
 
@@ -1208,6 +1206,10 @@ static void http_cache_io_handler(struct appctx *appctx)
                        if (appctx->st0 == HTTP_CACHE_INIT && *sent > cache_ptr->eoh &&
                                cache_channel_append_age_header(cache_ptr, res))
                                appctx->st0 = HTTP_CACHE_HEADER;
+                       else if (ret == len) {
+                               *sent = 0;
+                               appctx->st0 = HTTP_CACHE_FWD;
+                       }
                }
                else {
                        *sent = 0;