http: Fix WebSockets with Firefox

Firefox (134 at least) was unable to open a WebSocket connection to Unit
due to it sending a Connection header of

  Connection: keep-alive, Upgrade

However in Unit we were expecting only a single value in the header.

Fix the 'Connection' parsing in nxt_h1p_connection() to address this.

We keep the check for 'close' basically the same as that really should
be the only value.

Then we check for both of 'keep-alive' and 'upgrade'.

Closes: #1547
Signed-off-by: Andrew Clayton <a.clayton@nginx.com>

Author: ac000

src/nxt_h1proto.c

@@ -759,6 +759,7 @@ nxt_h1p_header_buffer_test(nxt_task_t *task, nxt_h1proto_t *h1p, nxt_conn_t *c,
 static nxt_int_t
 nxt_h1p_connection(void *ctx, nxt_http_field_t *field, uintptr_t data)
 {
+    const u_char        *end;
     nxt_http_request_t  *r;
 
     r = ctx;
@@ -768,15 +769,16 @@ nxt_h1p_connection(void *ctx, nxt_http_field_t *field, uintptr_t data)
         && nxt_memcasecmp(field->value, "close", 5) == 0)
     {
         r->proto.h1->keepalive = 0;
+        return NXT_OK;
+    }
 
-    } else if (field->value_length == 10
-               && nxt_memcasecmp(field->value, "keep-alive", 10) == 0)
-    {
+    end = field->value + field->value_length;
+
+    if (nxt_memcasestrn(field->value, end, "keep-alive", 10) != NULL) {
         r->proto.h1->keepalive = 1;
+    }
 
-    } else if (field->value_length == 7
-               && nxt_memcasecmp(field->value, "upgrade", 7) == 0)
-    {
+    if (nxt_memcasestrn(field->value, end, "upgrade", 7) != NULL) {
         r->proto.h1->connection_upgrade = 1;
     }