get_client_hello_ext_present

openresty/lua-nginx-module#2413
openresty/lua-nginx-module#2414

Author: climagabriel

lib/ngx/ssl/clienthello.lua

@@ -38,13 +38,18 @@ if subsystem == 'http' then
 
     int ngx_http_lua_ffi_ssl_set_protocols(ngx_http_request_t *r,
         int protocols, char **err);
+    int ngx_http_lua_ffi_ssl_get_client_hello_ext_present(ngx_http_request_t *r,
+        int **extensions, size_t *extensions_len, char **err);
     ]]
 
     ngx_lua_ffi_ssl_get_client_hello_server_name =
         C.ngx_http_lua_ffi_ssl_get_client_hello_server_name
     ngx_lua_ffi_ssl_get_client_hello_ext =
         C.ngx_http_lua_ffi_ssl_get_client_hello_ext
     ngx_lua_ffi_ssl_set_protocols = C.ngx_http_lua_ffi_ssl_set_protocols
+    ngx_lua_ffi_ssl_get_client_hello_ext_present =
+        C.ngx_http_lua_ffi_ssl_get_client_hello_ext_present
+
 
 elseif subsystem == 'stream' then
     ffi.cdef[[
@@ -102,6 +107,39 @@ function _M.get_client_hello_server_name()
     return nil, ffi_str(errmsg[0])
 end
 
+-- return ext, err
+function _M.get_client_hello_ext_present()
+    local r = get_request()
+    if not r then
+        error("no request found")
+    end
+
+    if ngx_phase() ~= "ssl_client_hello" then
+        error("API disabled in the current context")
+    end
+
+    local sizep = get_size_ptr()
+    local intp = ffi.new("int*[1]") -- array of len 1 of int pointers
+
+    local rc = ngx_lua_ffi_ssl_get_client_hello_ext_present(r, intp, sizep, errmsg)
+    if rc == FFI_OK then -- Convert C array to Lua table
+        local result = {}
+        local array = intp[0] -- This is now a pointer to the first integer
+        local size = tonumber(sizep[0])
+        for i=0,size-1,1 do
+            table_insert(result, array[i])
+        end
+
+        return result, size
+    end
+
+    -- NGX_DECLINED: no extension
+    if rc == -5 then
+        return nil
+    end
+
+    return nil, ffi_str(errmsg[0])
+end
 
 -- return ext, err
 function _M.get_client_hello_ext(ext_type)