FILES ----- */etc/nghttpx/nghttpx.conf* The default configuration file path nghttpx searches at startup. The configuration file path can be changed using :option:`--conf` option. Those lines which are staring ``#`` are treated as comment. The option name in the configuration file is the long command-line option name with leading ``--`` stripped (e.g., ``frontend``). Put ``=`` between option name and value. Don't put extra leading or trailing spaces. When specifying arguments including characters which have special meaning to a shell, we usually use quotes so that shell does not interpret them. When writing this configuration file, quotes for this purpose must not be used. For example, specify additional request header field, do this: .. code-block:: text add-request-header=foo: bar instead of: .. code-block:: text add-request-header="foo: bar" The options which do not take argument in the command-line *take* argument in the configuration file. Specify ``yes`` as an argument (e.g., ``http2-proxy=yes``). If other string is given, it is ignored. To specify private key and certificate file which are given as positional arguments in command-line, use ``private-key-file`` and ``certificate-file``. :option:`--conf` option cannot be used in the configuration file and will be ignored if specified. Error log Error log is written to stderr by default. It can be configured using :option:`--errorlog-file`. The format of log message is as follows: (:) It is a conbination of date and time when the log is written. It is in ISO 8601 format. It is a master process ID. It is a process ID which writes this log. It is a thread ID which writes this log. It would be unique within . and They are source file name, and line number which produce this log. It is a log message body. SIGNALS ------- SIGQUIT Shutdown gracefully. First accept pending connections and stop accepting connection. After all connections are handled, nghttpx exits. SIGHUP Reload configuration file given in :option:`--conf`. SIGUSR1 Reopen log files. SIGUSR2 Fork and execute nghttpx. It will execute the binary in the same path with same command-line arguments and environment variables. As of nghttpx version 1.20.0, the new master process sends SIGQUIT to the original master process when it is ready to serve requests. For the earlier versions of nghttpx, user has to send SIGQUIT to the original master process. The difference between SIGUSR2 (+ SIGQUIT) and SIGHUP is that former is usually used to execute new binary, and the master process is newly spawned. On the other hand, the latter just reloads configuration file, and the same master process continues to exist. .. note:: nghttpx consists of multiple processes: one process for processing these signals, and another one for processing requests. The former spawns the latter. The former is called master process, and the latter is called worker process. If neverbleed is enabled, the worker process spawns neverbleed daemon process which does RSA key processing. The above signal must be sent to the master process. If the other processes received one of them, it is ignored. This behaviour of these processes may change in the future release. In other words, in the future release, the processes other than master process may terminate upon the reception of these signals. Therefore these signals should not be sent to the processes other than master process. SERVER PUSH ----------- nghttpx supports HTTP/2 server push in default mode with Link header field. nghttpx looks for Link header field (`RFC 5988 `_) in response headers from backend server and extracts URI-reference with parameter ``rel=preload`` (see `preload `_) and pushes those URIs to the frontend client. Here is a sample Link header field to initiate server push: .. code-block:: text Link: ; rel=preload Link: ; rel=preload Currently, the following restriction is applied for server push: 1. The associated stream must have method "GET" or "POST". The associated stream's status code must be 200. This limitation may be loosened in the future release. nghttpx also supports server push if both frontend and backend are HTTP/2 in default mode. In this case, in addition to server push via Link header field, server push from backend is forwarded to frontend HTTP/2 session. HTTP/2 server push will be disabled if :option:`--http2-proxy` is used. UNIX DOMAIN SOCKET ------------------ nghttpx supports UNIX domain socket with a filename for both frontend and backend connections. Please note that current nghttpx implementation does not delete a socket with a filename. And on start up, if nghttpx detects that the specified socket already exists in the file system, nghttpx first deletes it. However, if SIGUSR2 is used to execute new binary and both old and new configurations use same filename, new binary does not delete the socket and continues to use it. OCSP STAPLING ------------- OCSP query is done using external Python script ``fetch-ocsp-response``, which has been originally developed in Perl as part of h2o project (https://github.com/h2o/h2o), and was translated into Python. The script file is usually installed under ``$(prefix)/share/nghttp2/`` directory. The actual path to script can be customized using :option:`--fetch-ocsp-response-file` option. If OCSP query is failed, previous OCSP response, if any, is continued to be used. :option:`--fetch-ocsp-response-file` option provides wide range of possibility to manage OCSP response. It can take an arbitrary script or executable. The requirement is that it supports the command-line interface of ``fetch-ocsp-response`` script, and it must return a valid DER encoded OCSP response on success. It must return exit code 0 on success, and 75 for temporary error, and the other error code for generic failure. For large cluster of servers, it is not efficient for each server to perform OCSP query using ``fetch-ocsp-response``. Instead, you can retrieve OCSP response in some way, and store it in a disk or a shared database. Then specify a program in :option:`--fetch-ocsp-response-file` to fetch it from those stores. This could provide a way to share the OCSP response between fleet of servers, and also any OCSP query strategy can be applied which may be beyond the ability of nghttpx itself or ``fetch-ocsp-response`` script. TLS SESSION RESUMPTION ---------------------- nghttpx supports TLS session resumption through both session ID and session ticket. SESSION ID RESUMPTION ~~~~~~~~~~~~~~~~~~~~~ By default, session ID is shared by all worker threads. If :option:`--tls-session-cache-memcached` is given, nghttpx will insert serialized session data to memcached with ``nghttpx:tls-session-cache:`` + lowercased hex string of session ID as a memcached entry key, with expiry time 12 hours. Session timeout is set to 12 hours. By default, connections to memcached server are not encrypted. To enable encryption, use ``tls`` keyword in :option:`--tls-session-cache-memcached` option. TLS SESSION TICKET RESUMPTION ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ By default, session ticket is shared by all worker threads. The automatic key rotation is also enabled by default. Every an hour, new encryption key is generated, and previous encryption key becomes decryption only key. We set session timeout to 12 hours, and thus we keep at most 12 keys. If :option:`--tls-ticket-key-memcached` is given, encryption keys are retrieved from memcached. nghttpx just reads keys from memcached; one has to deploy key generator program to update keys frequently (e.g., every 1 hour). The example key generator tlsticketupdate.go is available under contrib directory in nghttp2 archive. The memcached entry key is ``nghttpx:tls-ticket-key``. The data format stored in memcached is the binary format described below: .. code-block:: text +--------------+-------+----------------+ | VERSION (4) |LEN (2)|KEY(48 or 80) ... +--------------+-------+----------------+ ^ | | | +------------------------+ (LEN, KEY) pair can be repeated All numbers in the above figure is bytes. All integer fields are network byte order. First 4 bytes integer VERSION field, which must be 1. The 2 bytes integer LEN field gives the length of following KEY field, which contains key. If :option:`--tls-ticket-key-cipher`\=aes-128-cbc is used, LEN must be 48. If :option:`--tls-ticket-key-cipher`\=aes-256-cbc is used, LEN must be 80. LEN and KEY pair can be repeated multiple times to store multiple keys. The key appeared first is used as encryption key. All the remaining keys are used as decryption only. By default, connections to memcached server are not encrypted. To enable encryption, use ``tls`` keyword in :option:`--tls-ticket-key-memcached` option. If :option:`--tls-ticket-key-file` is given, encryption key is read from the given file. In this case, nghttpx does not rotate key automatically. To rotate key, one has to restart nghttpx (see SIGNALS). CERTIFICATE TRANSPARENCY ------------------------ nghttpx supports TLS ``signed_certificate_timestamp`` extension (`RFC 6962 `_). The relevant options are :option:`--tls-sct-dir` and ``sct-dir`` parameter in :option:`--subcert`. They takes a directory, and nghttpx reads all files whose extension is ``.sct`` under the directory. The ``*.sct`` files are encoded as ``SignedCertificateTimestamp`` struct described in `section 3.2 of RFC 69662 `_. This format is the same one used by `nginx-ct `_ and `mod_ssl_ct `_. `ct-submit `_ can be used to submit certificates to log servers, and obtain the ``SignedCertificateTimestamp`` struct which can be used with nghttpx. MRUBY SCRIPTING --------------- .. warning:: The current mruby extension API is experimental and not frozen. The API is subject to change in the future release. nghttpx allows users to extend its capability using mruby scripts. nghttpx has 2 hook points to execute mruby script: request phase and response phase. The request phase hook is invoked after all request header fields are received from client. The response phase hook is invoked after all response header fields are received from backend server. These hooks allows users to modify header fields, or common HTTP variables, like authority or request path, and even return custom response without forwarding request to backend servers. To specify mruby script file, use :option:`--mruby-file` option. The script will be evaluated once per thread on startup, and it must instantiate object and evaluate it as the return value (e.g., ``App.new``). This object is called app object. If app object defines ``on_req`` method, it is called with :rb:class:`Nghttpx::Env` object on request hook. Similarly, if app object defines ``on_resp`` method, it is called with :rb:class:`Nghttpx::Env` object on response hook. For each method invocation, user can can access :rb:class:`Nghttpx::Request` and :rb:class:`Nghttpx::Response` objects via :rb:attr:`Nghttpx::Env#req` and :rb:attr:`Nghttpx::Env#resp` respectively. .. rb:module:: Nghttpx .. rb:const:: REQUEST_PHASE Constant to represent request phase. .. rb:const:: RESPONSE_PHASE Constant to represent response phase. .. rb:class:: Env Object to represent current request specific context. .. rb:attr_reader:: req Return :rb:class:`Request` object. .. rb:attr_reader:: resp Return :rb:class:`Response` object. .. rb:attr_reader:: ctx Return Ruby hash object. It persists until request finishes. So values set in request phase hoo can be retrieved in response phase hook. .. rb:attr_reader:: phase Return the current phase. .. rb:attr_reader:: remote_addr Return IP address of a remote client. If connection is made via UNIX domain socket, this returns the string "localhost". .. rb:attr_reader:: server_addr Return address of server that accepted the connection. This is a string which specified in :option:`--frontend` option, excluding port number, and not a resolved IP address. For UNIX domain socket, this is a path to UNIX domain socket. .. rb:attr_reader:: server_port Return port number of the server frontend which accepted the connection from client. .. rb:attr_reader:: tls_used Return true if TLS is used on the connection. .. rb:attr_reader:: tls_sni Return the TLS SNI value which client sent in this connection. .. rb:class:: Request Object to represent request from client. The modification to Request object is allowed only in request phase hook. .. rb:attr_reader:: http_version_major Return HTTP major version. .. rb:attr_reader:: http_version_minor Return HTTP minor version. .. rb:attr_accessor:: method HTTP method. On assignment, copy of given value is assigned. We don't accept arbitrary method name. We will document them later, but well known methods, like GET, PUT and POST, are all supported. .. rb:attr_accessor:: authority Authority (i.e., example.org), including optional port component . On assignment, copy of given value is assigned. .. rb:attr_accessor:: scheme Scheme (i.e., http, https). On assignment, copy of given value is assigned. .. rb:attr_accessor:: path Request path, including query component (i.e., /index.html). On assignment, copy of given value is assigned. The path does not include authority component of URI. This may include query component. nghttpx makes certain normalization for path. It decodes percent-encoding for unreserved characters (see https://tools.ietf.org/html/rfc3986#section-2.3), and resolves ".." and ".". But it may leave characters which should be percent-encoded as is. So be careful when comparing path against desired string. .. rb:attr_reader:: headers Return Ruby hash containing copy of request header fields. Changing values in returned hash does not change request header fields actually used in request processing. Use :rb:meth:`Nghttpx::Request#add_header` or :rb:meth:`Nghttpx::Request#set_header` to change request header fields. .. rb:method:: add_header(key, value) Add header entry associated with key. The value can be single string or array of string. It does not replace any existing values associated with key. .. rb:method:: set_header(key, value) Set header entry associated with key. The value can be single string or array of string. It replaces any existing values associated with key. .. rb:method:: clear_headers Clear all existing request header fields. .. rb:method:: push(uri) Initiate to push resource identified by *uri*. Only HTTP/2 protocol supports this feature. For the other protocols, this method is noop. *uri* can be absolute URI, absolute path or relative path to the current request. For absolute or relative path, scheme and authority are inherited from the current request. Currently, method is always GET. nghttpx will issue request to backend servers to fulfill this request. The request and response phase hooks will be called for pushed resource as well. .. rb:class:: Response Object to represent response from backend server. .. rb:attr_reader:: http_version_major Return HTTP major version. .. rb:attr_reader:: http_version_minor Return HTTP minor version. .. rb:attr_accessor:: status HTTP status code. It must be in the range [200, 999], inclusive. The non-final status code is not supported in mruby scripting at the moment. .. rb:attr_reader:: headers Return Ruby hash containing copy of response header fields. Changing values in returned hash does not change response header fields actually used in response processing. Use :rb:meth:`Nghttpx::Response#add_header` or :rb:meth:`Nghttpx::Response#set_header` to change response header fields. .. rb:method:: add_header(key, value) Add header entry associated with key. The value can be single string or array of string. It does not replace any existing values associated with key. .. rb:method:: set_header(key, value) Set header entry associated with key. The value can be single string or array of string. It replaces any existing values associated with key. .. rb:method:: clear_headers Clear all existing response header fields. .. rb:method:: return(body) Return custom response *body* to a client. When this method is called in request phase hook, the request is not forwarded to the backend, and response phase hook for this request will not be invoked. When this method is called in response phase hook, response from backend server is canceled and discarded. The status code and response header fields should be set before using this method. To set status code, use :rb:meth To set response header fields, use :rb:attr:`Nghttpx::Response#status`. If status code is not set, 200 is used. :rb:meth:`Nghttpx::Response#add_header` and :rb:meth:`Nghttpx::Response#set_header`. When this method is invoked in response phase hook, the response headers are filled with the ones received from backend server. To send completely custom header fields, first call :rb:meth:`Nghttpx::Response#clear_headers` to erase all existing header fields, and then add required header fields. It is an error to call this method twice for a given request. .. rb:method:: send_info(status, headers) Send non-final (informational) response to a client. *status* must be in the range [100, 199], inclusive. *headers* is a hash containing response header fields. Its key must be a string, and the associated value must be either string or array of strings. Since this is not a final response, even if this method is invoked, request is still forwarded to a backend unless :rb:meth:`Nghttpx::Response#return` is called. This method can be called multiple times. It cannot be called after :rb:meth:`Nghttpx::Response#return` is called. MRUBY EXAMPLES ~~~~~~~~~~~~~~ Modify request path: .. code-block:: ruby class App def on_req(env) env.req.path = "/apps#{env.req.path}" end end App.new Don't forget to instantiate and evaluate object at the last line. Restrict permission of viewing a content to a specific client addresses: .. code-block:: ruby class App def on_req(env) allowed_clients = ["127.0.0.1", "::1"] if env.req.path.start_with?("/log/") && !allowed_clients.include?(env.remote_addr) then env.resp.status = 404 env.resp.return "permission denied" end end end App.new API ENDPOINTS ------------- nghttpx exposes API endpoints to manipulate it via HTTP based API. By default, API endpoint is disabled. To enable it, add a dedicated frontend for API using :option:`--frontend` option with "api" parameter. All requests which come from this frontend address, will be treated as API request. The response is normally JSON dictionary, and at least includes the following keys: status The status of the request processing. The following values are defined: Success The request was successful. Failure The request was failed. No change has been made. code HTTP status code Additionally, depending on the API endpoint, ``data`` key may be present, and its value contains the API endpoint specific data. We wrote "normally", since nghttpx may return ordinal HTML response in some cases where the error has occurred before reaching API endpoint (e.g., header field is too large). The following section describes available API endpoints. POST /api/v1beta1/backendconfig ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ This API replaces the current backend server settings with the requested ones. The request method should be POST, but PUT is also acceptable. The request body must be nghttpx configuration file format. For configuration file format, see `FILES`_ section. The line separator inside the request body must be single LF (0x0A). Currently, only :option:`backend <--backend>` option is parsed, the others are simply ignored. The semantics of this API is replace the current backend with the backend options in request body. Describe the desired set of backend severs, and nghttpx makes it happen. If there is no :option:`backend <--backend>` option is found in request body, the current set of backend is replaced with the :option:`backend <--backend>` option's default value, which is ``127.0.0.1,80``. The replacement is done instantly without breaking existing connections or requests. It also avoids any process creation as is the case with hot swapping with signals. The one limitation is that only numeric IP address is allowd in :option:`backend <--backend>` in request body unless "dns" parameter is used while non numeric hostname is allowed in command-line or configuration file is read using :option:`--conf`. GET /api/v1beta1/configrevision ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ This API returns configuration revision of the current nghttpx. The configuration revision is opaque string, and it changes after each reloading by SIGHUP. With this API, an external application knows that whether nghttpx has finished reloading its configuration by comparing the configuration revisions between before and after reloading. It is recommended to disable persistent (keep-alive) connection for this purpose in order to avoid to send a request using the reused connection which may bound to an old process. This API returns response including ``data`` key. Its value is JSON object, and it contains at least the following key: configRevision The configuration revision of the current nghttpx SEE ALSO -------- :manpage:`nghttp(1)`, :manpage:`nghttpd(1)`, :manpage:`h2load(1)`