feature: ssl: add new API function to set SSL ciphers

lib/ngx/ssl.lua

@@ -58,6 +58,9 @@ int ngx_http_lua_ffi_set_priv_key(void *r, void *cdata, char **err);
 void ngx_http_lua_ffi_free_cert(void *cdata);
 
 void ngx_http_lua_ffi_free_priv_key(void *cdata);
+
+int ngx_http_lua_ffi_ssl_set_ciphers(ngx_http_request_t *r,
+    const char *ciphers, char **err);
 ]]
 
 
@@ -261,6 +264,21 @@ function _M.set_priv_key(priv_key)
 end
 
 
+function _M.set_ciphers(ciphers)
+    local r = getfenv(0).__ngx_req
+    if not r then
+        return error("no request found")
+    end
+
+    local rc = C.ngx_http_lua_ffi_ssl_set_ciphers(r, ciphers, errmsg)
+    if rc == FFI_OK then
+        return true
+    end
+
+    return nil, ffi_str(errmsg[0])
+end
+
+
 do
     _M.SSL3_VERSION = 0x0300
     _M.TLS1_VERSION = 0x0301

lib/ngx/ssl.md

@@ -23,6 +23,7 @@ Table of Contents
     * [parse_pem_priv_key](#parse_pem_priv_key)
     * [set_cert](#set_cert)
     * [set_priv_key](#set_priv_key)
+    * [set_ciphers](#set_ciphers)
 * [Community](#community)
     * [English Mailing List](#english-mailing-list)
     * [Chinese Mailing List](#chinese-mailing-list)
@@ -381,6 +382,20 @@ This function was first added in version `0.1.7`.
 
 [Back to TOC](#table-of-contents)
 
+set_ciphers
+------------
+**syntax:** *ok, err = ssl.set_ciphers(ciphers)*
+
+**context:** *ssl_certificate_by_lua**
+
+Sets the enabled SSL ciphers for the current SSL connection. The `ciphers` string format is the same as the one accepted by OpenSSL.
+
+Returns `true` on success, or a `nil` value and a string describing the error otherwise.
+
+This function was first added in version `0.2.0`.
+
+[Back to TOC](#table-of-contents)
+
 Community
 =========
 

t/ssl.t

@@ -2062,3 +2062,113 @@ qr/\[error\] .*? failed to parse pem key: PEM_read_bio_PrivateKey\(\) failed/
 [alert]
 [emerg]
 [crit]
+
+
+
+=== TEST 20: set ciphers
+--- http_config
+    lua_package_path "$TEST_NGINX_LUA_PACKAGE_PATH/?.lua;;";
+
+    server {
+        listen unix:$TEST_NGINX_HTML_DIR/nginx.sock ssl;
+        server_name   test.com;
+
+        ssl_ciphers AES128;
+
+        ssl_certificate_by_lua_block {
+            local ssl = require "ngx.ssl"
+
+            local ok, err = ssl.set_ciphers("AES256")
+            if not ok then
+                ngx.say("failed to connect: ", err)
+                return
+            end
+        }
+
+        ssl_certificate ../../cert/chain/chain.pem;
+        ssl_certificate_key ../../cert/chain/test-com.key.pem;
+
+        server_tokens off;
+        location /foo {
+            default_type 'text/plain';
+            content_by_lua_block { ngx.status = 201 ngx.say("foo") ngx.exit(201) }
+            more_clear_headers Date;
+        }
+    }
+--- config
+    server_tokens off;
+    lua_ssl_trusted_certificate ../../cert/chain/root-ca.crt;
+    lua_ssl_verify_depth 3;
+    lua_ssl_ciphers AES256;
+
+    location /t {
+        content_by_lua_block {
+            do
+                local sock = ngx.socket.tcp()
+
+                sock:settimeout(3000)
+
+                local ok, err = sock:connect("unix:$TEST_NGINX_HTML_DIR/nginx.sock")
+                if not ok then
+                    ngx.say("failed to connect: ", err)
+                    return
+                end
+
+                ngx.say("connected: ", ok)
+
+                local sess, err = sock:sslhandshake(nil, "test.com", true)
+                if not sess then
+                    ngx.say("failed to do SSL handshake: ", err)
+                    return
+                end
+
+                ngx.say("ssl handshake: ", type(sess))
+
+                local req = "GET /foo HTTP/1.0\r\nHost: test.com\r\nConnection: close\r\n\r\n"
+                local bytes, err = sock:send(req)
+                if not bytes then
+                    ngx.say("failed to send http request: ", err)
+                    return
+                end
+
+                ngx.say("sent http request: ", bytes, " bytes.")
+
+                while true do
+                    local line, err = sock:receive()
+                    if not line then
+                        -- ngx.say("failed to recieve response status line: ", err)
+                        break
+                    end
+
+                    ngx.say("received: ", line)
+                end
+
+                local ok, err = sock:close()
+                ngx.say("close: ", ok, " ", err)
+            end  -- do
+            -- collectgarbage()
+        }
+    }
+
+--- request
+GET /t
+--- response_body
+connected: 1
+ssl handshake: userdata
+sent http request: 56 bytes.
+received: HTTP/1.1 201 Created
+received: Server: nginx
+received: Content-Type: text/plain
+received: Content-Length: 4
+received: Connection: close
+received: 
+received: foo
+close: 1 nil
+
+--- error_log
+lua ssl server name: "test.com"
+cipher: "ECDHE-RSA-AES256-GCM-SHA384
+
+--- no_error_log
+[error]
+[alert]