[nginx] gRPC: handling GOAWAY with a higher last stream identifier.

[Maxim Dounin]

details:   https://hg.nginx.org/nginx/rev/f5732fa038ad
branches:  stable-1.20
changeset: 7957:f5732fa038ad
user:      Sergey Kandaurov <pluknet at nginx.com>
date:      Thu Jun 17 11:43:55 2021 +0300
description:
gRPC: handling GOAWAY with a higher last stream identifier.

Previously, once received from upstream, it couldn't limit
opening additional streams in a cached keepalive connection.

diffstat:

 src/http/modules/ngx_http_grpc_module.c |  9 +++++++++
 1 files changed, 9 insertions(+), 0 deletions(-)

diffs (61 lines):

diff -r ae70fcb8ac93 -r f5732fa038ad src/http/modules/ngx_http_grpc_module.c
--- a/src/http/modules/ngx_http_grpc_module.c	Tue Jun 01 17:37:51 2021 +0300
+++ b/src/http/modules/ngx_http_grpc_module.c	Thu Jun 17 11:43:55 2021 +0300
@@ -124,6 +124,7 @@ typedef struct {
     unsigned                   done:1;
     unsigned                   status:1;
     unsigned                   rst:1;
+    unsigned                   goaway:1;
 
     ngx_http_request_t        *request;
 
@@ -1213,6 +1214,7 @@ ngx_http_grpc_reinit_request(ngx_http_re
     ctx->done = 0;
     ctx->status = 0;
     ctx->rst = 0;
+    ctx->goaway = 0;
     ctx->connection = NULL;
 
     return NGX_OK;
@@ -1568,6 +1570,7 @@ ngx_http_grpc_body_output_filter(void *d
             && ctx->out == NULL
             && ctx->output_closed
             && !ctx->output_blocked
+            && !ctx->goaway
             && ctx->state == ngx_http_grpc_st_start)
         {
             u->keepalive = 1;
@@ -1717,6 +1720,8 @@ ngx_http_grpc_process_header(ngx_http_re
                 return NGX_HTTP_UPSTREAM_INVALID_HEADER;
             }
 
+            ctx->goaway = 1;
+
             continue;
         }
 
@@ -1910,6 +1915,7 @@ ngx_http_grpc_process_header(ngx_http_re
                         && ctx->out == NULL
                         && ctx->output_closed
                         && !ctx->output_blocked
+                        && !ctx->goaway
                         && b->last == b->pos)
                     {
                         u->keepalive = 1;
@@ -2038,6 +2044,7 @@ ngx_http_grpc_filter(void *data, ssize_t
                     if (ctx->in == NULL
                         && ctx->output_closed
                         && !ctx->output_blocked
+                        && !ctx->goaway
                         && ctx->state == ngx_http_grpc_st_start)
                     {
                         u->keepalive = 1;
@@ -2207,6 +2214,8 @@ ngx_http_grpc_filter(void *data, ssize_t
                 return NGX_ERROR;
             }
 
+            ctx->goaway = 1;
+
             continue;
         }