feat: bound request and response body buffering in plugins

apisix/plugins/ai-prompt-decorator.lua

@@ -40,6 +40,13 @@ local prompts = {
 local schema = {
     type = "object",
     properties = {
+        max_req_body_size = {
+            type = "integer",
+            minimum = 1,
+            default = 67108864,
+            description = "maximum request body size in bytes buffered into "
+                       .. "memory; larger request bodies are rejected",
+        },
         prepend = prompts,
         append = prompts,
     },
@@ -64,8 +71,8 @@ function _M.check_schema(conf)
 end
 
 
-local function get_request_body_table()
-    local body, err = core.request.get_body()
+local function get_request_body_table(max_size)
+    local body, err = core.request.get_body(max_size)
     if not body then
         return nil, { message = "could not get body: " .. (err or "request body is empty") }
     end
@@ -80,7 +87,7 @@ end
 
 
 function _M.rewrite(conf, ctx)
-    local body_tab, err = get_request_body_table()
+    local body_tab, err = get_request_body_table(conf.max_req_body_size)
     if not body_tab then
         return 400, err
     end

apisix/plugins/ai-prompt-guard.lua

@@ -28,6 +28,13 @@ local plugin_name = "ai-prompt-guard"
 local schema = {
     type = "object",
     properties = {
+        max_req_body_size = {
+            type = "integer",
+            minimum = 1,
+            default = 67108864,
+            description = "maximum request body size in bytes buffered into "
+                       .. "memory; larger request bodies are rejected",
+        },
         match_all_roles = {
             type = "boolean",
             default = false,
@@ -98,7 +105,7 @@ end
 
 
 function _M.access(conf, ctx)
-    local body = core.request.get_body()
+    local body = core.request.get_body(conf.max_req_body_size)
     if not body then
         core.log.error("Empty request body")
         return 400, {message = "Empty request body"}

apisix/plugins/ai-prompt-template.lua

@@ -41,6 +41,13 @@ local prompts = {
 local schema = {
     type = "object",
     properties = {
+        max_req_body_size = {
+            type = "integer",
+            minimum = 1,
+            default = 67108864,
+            description = "maximum request body size in bytes buffered into "
+                       .. "memory; larger request bodies are rejected",
+        },
         templates = {
             type = "array",
             minItems = 1,
@@ -90,8 +97,8 @@ function _M.check_schema(conf)
 end
 
 
-local function get_request_body_table()
-    local body, err = core.request.get_body()
+local function get_request_body_table(max_size)
+    local body, err = core.request.get_body(max_size)
     if not body then
         return nil, { message = "could not get body: " .. (err or "request body is empty") }
     end
@@ -115,7 +122,7 @@ local function find_template(conf, template_name)
 end
 
 function _M.rewrite(conf, ctx)
-    local body_tab, err = get_request_body_table()
+    local body_tab, err = get_request_body_table(conf.max_req_body_size)
     if not body_tab then
         return 400, err
     end

apisix/plugins/ai-proxy/schema.lua

@@ -248,7 +248,7 @@ _M.ai_proxy_schema = {
             minimum = 1,
             default = 67108864,
             description = "maximum request body size in bytes the plugin reads "
-                       .. "into memory; larger requests are rejected with 413. "
+                       .. "into memory; larger request bodies are rejected. "
                        .. "Prevents unbounded memory buffering of large bodies.",
         },
         max_stream_duration_ms = {
@@ -373,7 +373,7 @@ _M.ai_proxy_multi_schema = {
             minimum = 1,
             default = 67108864,
             description = "maximum request body size in bytes the plugin reads "
-                       .. "into memory; larger requests are rejected with 413. "
+                       .. "into memory; larger request bodies are rejected. "
                        .. "Prevents unbounded memory buffering of large bodies.",
         },
         max_stream_duration_ms = {

apisix/plugins/ai-request-rewrite.lua

@@ -60,6 +60,13 @@ local model_options_schema = {
 local schema = {
     type = "object",
     properties = {
+        max_req_body_size = {
+            type = "integer",
+            minimum = 1,
+            default = 67108864,
+            description = "maximum request body size in bytes buffered into "
+                       .. "memory; larger request bodies are rejected",
+        },
         prompt = {
             type = "string",
             description = "The prompt to rewrite client request."
@@ -172,7 +179,7 @@ function _M.check_schema(conf)
 end
 
 function _M.access(conf, ctx)
-    local client_request_body, err = core.request.get_body()
+    local client_request_body, err = core.request.get_body(conf.max_req_body_size)
     if err then
         core.log.warn("failed to get request body: ", err)
         return HTTP_BAD_REQUEST

apisix/plugins/authz-keycloak.lua

@@ -27,6 +27,13 @@ local pairs = pairs
 local schema = {
     type = "object",
     properties = {
+        max_req_body_size = {
+            type = "integer",
+            minimum = 1,
+            default = 67108864,
+            description = "maximum request body size in bytes buffered into "
+                       .. "memory; larger request bodies are rejected",
+        },
         discovery = {type = "string", minLength = 1, maxLength = 4096},
         token_endpoint = {type = "string", minLength = 1, maxLength = 4096},
         resource_registration_endpoint = {type = "string", minLength = 1, maxLength = 4096},
@@ -694,7 +701,7 @@ end
 local function generate_token_using_password_grant(conf,ctx)
     log.debug("generate_token_using_password_grant Function Called")
 
-    local body, err = core.request.get_body()
+    local body, err = core.request.get_body(conf.max_req_body_size)
     if err or not body then
         log.error("Failed to get request body: ", err)
         return 503

apisix/plugins/body-transformer.lua

@@ -48,6 +48,20 @@ local schema = {
     properties = {
         request = transform_schema,
         response = transform_schema,
+        max_req_body_size = {
+            type = "integer",
+            minimum = 1,
+            default = 67108864,
+            description = "maximum request body size in bytes buffered into "
+                       .. "memory; larger request bodies are rejected",
+        },
+        max_resp_body_size = {
+            type = "integer",
+            minimum = 1,
+            default = 67108864,
+            description = "maximum response body size in bytes buffered into "
+                       .. "memory; larger responses are truncated",
+        },
     },
     anyOf = {
         {required = {"request"}},
@@ -233,7 +247,11 @@ function _M.rewrite(conf, ctx)
         local request_method  = ngx.var.request_method
         conf = core.table.deepcopy(conf)
         ctx.body_transformer_conf = conf
-        local body = core.request.get_body()
+        local body, err = core.request.get_body(conf.max_req_body_size)
+        if err then
+            core.log.error("failed to get request body: ", err)
+            return 413
+        end
         set_input_format(conf, "request", ctx.var.http_content_type, request_method)
         local out, status, err = transform(conf, body, "request", ctx, request_method)
         if not out then
@@ -262,7 +280,7 @@ function _M.body_filter(_, ctx)
         return
     end
     if conf.response then
-        local body = core.response.hold_body_chunk(ctx)
+        local body = core.response.hold_body_chunk(ctx, false, conf.max_resp_body_size)
         if ngx.arg[2] == false and not body then
             return
         end

apisix/plugins/cas-auth.lua

@@ -40,6 +40,13 @@ local plugin_name = "cas-auth"
 local schema = {
     type = "object",
     properties = {
+        max_req_body_size = {
+            type = "integer",
+            minimum = 1,
+            default = 67108864,
+            description = "maximum request body size in bytes buffered into "
+                       .. "memory; larger request bodies are rejected",
+        },
         idp_uri = {type = "string"},
         cas_callback_uri = {
             type = "string",
@@ -358,7 +365,7 @@ function _M.access(conf, ctx)
     end
 
     if method == "POST" and uri == cas_callback_path then
-        local data = core.request.get_body()
+        local data = core.request.get_body(conf.max_req_body_size)
         local ticket = data and data:match("<samlp:SessionIndex>(.+)</samlp:SessionIndex>")
         if ticket == nil then
             return ngx.HTTP_BAD_REQUEST,

apisix/plugins/degraphql.lua

@@ -25,6 +25,13 @@ local type = type
 local schema = {
     type = "object",
     properties = {
+        max_req_body_size = {
+            type = "integer",
+            minimum = 1,
+            default = 67108864,
+            description = "maximum request body size in bytes buffered into "
+                       .. "memory; larger request bodies are rejected",
+        },
         query = {
             type = "string",
             minLength = 1,
@@ -75,7 +82,7 @@ end
 
 
 local function fetch_post_variables(conf)
-    local req_body, err = core.request.get_body()
+    local req_body, err = core.request.get_body(conf.max_req_body_size)
     if err ~= nil then
         core.log.error("failed to get request body: ", err)
         return nil, 503
@@ -146,7 +153,7 @@ function _M.access(conf, ctx)
     if meth == "POST" then
         if not conf.variables then
             -- the set_body_data requires to read the body first
-            core.request.get_body()
+            core.request.get_body(conf.max_req_body_size)
         end
 
         core.request.set_header(ctx, "Content-Type", "application/json")

apisix/plugins/grpc-transcode.lua

@@ -47,6 +47,13 @@ local pb_option_def = {
 local schema = {
     type = "object",
     properties = {
+        max_resp_body_size = {
+            type = "integer",
+            minimum = 1,
+            default = 67108864,
+            description = "maximum response body size in bytes buffered into "
+                       .. "memory for transcoding; larger responses are truncated",
+        },
         proto_id  = schema_def.id_schema,
         service = {
             description = "the grpc service name",
@@ -200,7 +207,8 @@ function _M.body_filter(conf, ctx)
     end
 
     local err = response(ctx, proto_obj, conf.service, conf.method, conf.pb_option,
-                         conf.show_status_in_body, conf.status_detail_type)
+                         conf.show_status_in_body, conf.status_detail_type,
+                         conf.max_resp_body_size)
     if err then
         core.log.error("transform response error: ", err)
         return

apisix/plugins/grpc-transcode/response.lua

@@ -93,8 +93,9 @@ local function handle_error_response(status_detail_type, proto)
 end
 
 
-return function(ctx, proto, service, method, pb_option, show_status_in_body, status_detail_type)
-    local buffer = core.response.hold_body_chunk(ctx)
+return function(ctx, proto, service, method, pb_option, show_status_in_body, status_detail_type,
+                max_resp_body_size)
+    local buffer = core.response.hold_body_chunk(ctx, false, max_resp_body_size)
     if not buffer then
         return nil
     end

apisix/plugins/grpc-web.lua

@@ -41,6 +41,13 @@ local plugin_name = "grpc-web"
 local schema = {
     type = "object",
     properties = {
+        max_req_body_size = {
+            type = "integer",
+            minimum = 1,
+            default = 67108864,
+            description = "maximum request body size in bytes buffered into "
+                       .. "memory; larger request bodies are rejected",
+        },
         cors_allow_headers = {
             description =
             "multiple header use ',' to split. default: content-type,x-grpc-web,x-user-agent.",
@@ -143,7 +150,7 @@ function _M.access(conf, ctx)
     end
 
     -- set grpc body
-    local body, err = core.request.get_body()
+    local body, err = core.request.get_body(conf.max_req_body_size)
     if err or not body then
         core.log.error("failed to read request body, err: ", err)
         return exit(ctx, 400)

apisix/plugins/http-dubbo.lua

@@ -32,6 +32,13 @@ local plugin_name = "http-dubbo"
 local schema = {
     type = "object",
     properties = {
+        max_req_body_size = {
+            type = "integer",
+            minimum = 1,
+            default = 67108864,
+            description = "maximum request body size in bytes buffered into "
+                       .. "memory; larger request bodies are rejected",
+        },
         service_name = {
             type = "string",
             minLength = 1,
@@ -174,15 +181,24 @@ local function get_dubbo_request(conf, ctx)
         serialized = serialization_header == "true"
     end
     if serialized then
-        params = core.request.get_body()
+        local body, err = core.request.get_body(conf.max_req_body_size)
+        if err then
+            core.log.error("failed to get request body: ", err)
+            return nil, 413
+        end
+        params = body
         if params then
             local end_of_params = core.string.sub(params, -1)
             if end_of_params ~= "\n" then
                 params = params .. "\n"
             end
         end
     else
-        local body_data = core.request.get_body()
+        local body_data, err = core.request.get_body(conf.max_req_body_size)
+        if err then
+            core.log.error("failed to get request body: ", err)
+            return nil, 413
+        end
         if body_data then
             local lua_object = core.json.decode(body_data);
             for _, v in pairs(lua_object) do
@@ -231,7 +247,11 @@ function _M.before_proxy(conf, ctx)
         core.log.error("failed to connect to upstream ", err)
         return 502
     end
-    local request = get_dubbo_request(conf, ctx)
+    local request, err_code = get_dubbo_request(conf, ctx)
+    if not request then
+        sock:close()
+        return err_code
+    end
     local bytes, _ = sock:send(request)
     if bytes > 0 then
         local header, _ = sock:receiveany(16);

apisix/plugins/oas-validator.lua

@@ -35,6 +35,13 @@ local DEFAULT_SPEC_URL_TTL = 3600
 local schema = {
     type = "object",
     properties = {
+        max_req_body_size = {
+            type = "integer",
+            minimum = 1,
+            default = 67108864,
+            description = "maximum request body size in bytes buffered into "
+                       .. "memory; larger request bodies are rejected",
+        },
         spec = {
             description = "schema against which the request/response will be validated",
             type = "string",
@@ -244,7 +251,7 @@ function _M.access(conf, ctx)
 
     local req_body
     if not conf.skip_request_body_validation then
-        local body, body_err = core.request.get_body()
+        local body, body_err = core.request.get_body(conf.max_req_body_size)
         if body_err ~= nil then
             core.log.error("failed reading request body, err: " .. body_err)
             return 500, {message = "error reading the request body. err: " .. body_err}