modules/http2/h2.h - httpd - Git at Google

 /* Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements.  See the NOTICE file distributed with
  * this work for additional information regarding copyright ownership.
  * The ASF licenses this file to You under the Apache License, Version 2.0
  * (the "License"); you may not use this file except in compliance with
  * the License.  You may obtain a copy of the License at
  *
  *     http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 #ifndef __mod_h2__h2__
 #define __mod_h2__h2__

 #include <apr_version.h>
 #include <ap_mmn.h>

 struct h2_session;
 struct h2_stream;

 /*
  * When apr pollsets can poll file descriptors (e.g. pipes),
  * we use it for polling stream input/output.
  */
 #ifdef H2_NO_PIPES
 #define H2_USE_PIPES            0
 #else
 #define H2_USE_PIPES            (APR_FILES_AS_SOCKETS && APR_VERSION_AT_LEAST(1,6,0))
 #endif

 /**
  * The magic PRIamble of RFC 7540 that is always sent when starting
  * a h2 communication.
  */
 extern const char *H2_MAGIC_TOKEN;

 #define H2_ERR_NO_ERROR             (0x00)
 #define H2_ERR_PROTOCOL_ERROR       (0x01)
 #define H2_ERR_INTERNAL_ERROR       (0x02)
 #define H2_ERR_FLOW_CONTROL_ERROR   (0x03)
 #define H2_ERR_SETTINGS_TIMEOUT     (0x04)
 #define H2_ERR_STREAM_CLOSED        (0x05)
 #define H2_ERR_FRAME_SIZE_ERROR     (0x06)
 #define H2_ERR_REFUSED_STREAM       (0x07)
 #define H2_ERR_CANCEL               (0x08)
 #define H2_ERR_COMPRESSION_ERROR    (0x09)
 #define H2_ERR_CONNECT_ERROR        (0x0a)
 #define H2_ERR_ENHANCE_YOUR_CALM    (0x0b)
 #define H2_ERR_INADEQUATE_SECURITY  (0x0c)
 #define H2_ERR_HTTP_1_1_REQUIRED    (0x0d)

 #define H2_HEADER_METHOD     ":method"
 #define H2_HEADER_METHOD_LEN 7
 #define H2_HEADER_SCHEME     ":scheme"
 #define H2_HEADER_SCHEME_LEN 7
 #define H2_HEADER_AUTH       ":authority"
 #define H2_HEADER_AUTH_LEN   10
 #define H2_HEADER_PATH       ":path"
 #define H2_HEADER_PATH_LEN   5
 #define H2_CRLF             "\r\n"

 /* Size of the frame header itself in HTTP/2 */
 #define H2_FRAME_HDR_LEN            9

 /* Max data size to write so it fits inside a TLS record */
 #define H2_DATA_CHUNK_SIZE          ((16*1024) - 100 - H2_FRAME_HDR_LEN)

 /* Maximum number of padding bytes in a frame, rfc7540 */
 #define H2_MAX_PADLEN               256
 /* Initial default window size, RFC 7540 ch. 6.5.2 */
 #define H2_INITIAL_WINDOW_SIZE      ((64*1024)-1)

 #define H2_STREAM_CLIENT_INITIATED(id)      (id&0x01)

 #define H2_ALEN(a)          (sizeof(a)/sizeof((a)[0]))

 #define H2MAX(x,y) ((x) > (y) ? (x) : (y))
 #define H2MIN(x,y) ((x) < (y) ? (x) : (y))

 typedef enum {
     H2_DEPENDANT_AFTER,
     H2_DEPENDANT_INTERLEAVED,
     H2_DEPENDANT_BEFORE,
 } h2_dependency;

 typedef struct h2_priority {
     h2_dependency dependency;
     int           weight;
 } h2_priority;

 typedef enum {
     H2_PUSH_NONE,
     H2_PUSH_DEFAULT,
     H2_PUSH_HEAD,
     H2_PUSH_FAST_LOAD,
 } h2_push_policy;

 typedef enum {
     H2_SESSION_ST_INIT,             /* send initial SETTINGS, etc. */
     H2_SESSION_ST_DONE,             /* finished, connection close */
     H2_SESSION_ST_IDLE,             /* nothing to write, expecting data inc */
     H2_SESSION_ST_BUSY,             /* read/write without stop */
     H2_SESSION_ST_WAIT,             /* waiting for c1 incoming + c2s output */
     H2_SESSION_ST_CLEANUP,          /* pool is being cleaned up */
 } h2_session_state;

 typedef struct h2_session_props {
     int accepted_max;      /* the highest remote stream id was/will be handled */
     int completed_max;     /* the highest remote stream completed */
     int emitted_count;     /* the number of local streams sent */
     int emitted_max;       /* the highest local stream id sent */
     int error;             /* the last session error encountered */
     const char *error_msg; /* the short message given on the error */
     unsigned int accepting : 1;     /* if the session is accepting new streams */
     unsigned int shutdown : 1;      /* if the final GOAWAY has been sent */
 } h2_session_props;

 typedef enum h2_stream_state_t {
     H2_SS_IDLE,
     H2_SS_RSVD_R,
     H2_SS_RSVD_L,
     H2_SS_OPEN,
     H2_SS_CLOSED_R,
     H2_SS_CLOSED_L,
     H2_SS_CLOSED,
     H2_SS_CLEANUP,
     H2_SS_MAX
 } h2_stream_state_t;

 typedef enum {
     H2_SEV_CLOSED_L,
     H2_SEV_CLOSED_R,
     H2_SEV_CANCELLED,
     H2_SEV_EOS_SENT,
     H2_SEV_IN_ERROR,
     H2_SEV_IN_DATA_PENDING,
     H2_SEV_OUT_C1_BLOCK,
 } h2_stream_event_t;


 /* h2_request is the transformer of HTTP2 streams into HTTP/1.1 internal
  * format that will be fed to various httpd input filters to finally
  * become a request_rec to be handled by soemone.
  */
 typedef struct h2_request h2_request;
 struct h2_request {
     const char *method; /* pseudo header values, see ch. 8.1.2.3 */
     const char *scheme;
     const char *authority;
     const char *path;
     apr_table_t *headers;

     apr_time_t request_time;
     apr_off_t raw_bytes;        /* RAW network bytes that generated this request - if known. */
     int http_status;            /* Store a possible HTTP status code that gets
                                  * defined before creating the dummy HTTP/1.1
                                  * request e.g. due to an error already
                                  * detected.
                                  */
 };

 /*
  * A possible HTTP status code is not defined yet. See the http_status field
  * in struct h2_request above for further explanation.
  */
 #define H2_HTTP_STATUS_UNSET (0)

 typedef apr_status_t h2_io_data_cb(void *ctx, const char *data, apr_off_t len);

 typedef int h2_stream_pri_cmp_fn(int stream_id1, int stream_id2, void *session);
 typedef struct h2_stream *h2_stream_get_fn(struct h2_session *session, int stream_id);

 /* Note key to attach stream id to conn_rec/request_rec instances */
 #define H2_HDR_CONFORMANCE      "http2-hdr-conformance"
 #define H2_HDR_CONFORMANCE_UNSAFE      "unsafe"
 #define H2_PUSH_MODE_NOTE       "http2-push-mode"


 #if AP_MODULE_MAGIC_AT_LEAST(20211221, 6)
 #define AP_HAS_RESPONSE_BUCKETS     1

 #else /* AP_MODULE_MAGIC_AT_LEAST(20211221, 6) */
 #define AP_HAS_RESPONSE_BUCKETS     0

 #endif /* else AP_MODULE_MAGIC_AT_LEAST(20211221, 6) */

 #endif /* defined(__mod_h2__h2__) */
	/* Licensed to the Apache Software Foundation (ASF) under one or more
	* contributor license agreements. See the NOTICE file distributed with
	* this work for additional information regarding copyright ownership.
	* The ASF licenses this file to You under the Apache License, Version 2.0
	* (the "License"); you may not use this file except in compliance with
	* the License. You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#ifndef __mod_h2__h2__
	#define __mod_h2__h2__

	#include <apr_version.h>
	#include <ap_mmn.h>

	struct h2_session;
	struct h2_stream;

	/*
	* When apr pollsets can poll file descriptors (e.g. pipes),
	* we use it for polling stream input/output.
	*/
	#ifdef H2_NO_PIPES
	#define H2_USE_PIPES 0
	#else
	#define H2_USE_PIPES (APR_FILES_AS_SOCKETS && APR_VERSION_AT_LEAST(1,6,0))
	#endif

	/**
	* The magic PRIamble of RFC 7540 that is always sent when starting
	* a h2 communication.
	*/
	extern const char *H2_MAGIC_TOKEN;

	#define H2_ERR_NO_ERROR (0x00)
	#define H2_ERR_PROTOCOL_ERROR (0x01)
	#define H2_ERR_INTERNAL_ERROR (0x02)
	#define H2_ERR_FLOW_CONTROL_ERROR (0x03)
	#define H2_ERR_SETTINGS_TIMEOUT (0x04)
	#define H2_ERR_STREAM_CLOSED (0x05)
	#define H2_ERR_FRAME_SIZE_ERROR (0x06)
	#define H2_ERR_REFUSED_STREAM (0x07)
	#define H2_ERR_CANCEL (0x08)
	#define H2_ERR_COMPRESSION_ERROR (0x09)
	#define H2_ERR_CONNECT_ERROR (0x0a)
	#define H2_ERR_ENHANCE_YOUR_CALM (0x0b)
	#define H2_ERR_INADEQUATE_SECURITY (0x0c)
	#define H2_ERR_HTTP_1_1_REQUIRED (0x0d)

	#define H2_HEADER_METHOD ":method"
	#define H2_HEADER_METHOD_LEN 7
	#define H2_HEADER_SCHEME ":scheme"
	#define H2_HEADER_SCHEME_LEN 7
	#define H2_HEADER_AUTH ":authority"
	#define H2_HEADER_AUTH_LEN 10
	#define H2_HEADER_PATH ":path"
	#define H2_HEADER_PATH_LEN 5
	#define H2_CRLF "\r\n"

	/* Size of the frame header itself in HTTP/2 */
	#define H2_FRAME_HDR_LEN 9

	/* Max data size to write so it fits inside a TLS record */
	#define H2_DATA_CHUNK_SIZE ((16*1024) - 100 - H2_FRAME_HDR_LEN)

	/* Maximum number of padding bytes in a frame, rfc7540 */
	#define H2_MAX_PADLEN 256
	/* Initial default window size, RFC 7540 ch. 6.5.2 */
	#define H2_INITIAL_WINDOW_SIZE ((64*1024)-1)

	#define H2_STREAM_CLIENT_INITIATED(id) (id&0x01)

	#define H2_ALEN(a) (sizeof(a)/sizeof((a)[0]))

	#define H2MAX(x,y) ((x) > (y) ? (x) : (y))
	#define H2MIN(x,y) ((x) < (y) ? (x) : (y))

	typedef enum {
	H2_DEPENDANT_AFTER,
	H2_DEPENDANT_INTERLEAVED,
	H2_DEPENDANT_BEFORE,
	} h2_dependency;

	typedef struct h2_priority {
	h2_dependency dependency;
	int weight;
	} h2_priority;

	typedef enum {
	H2_PUSH_NONE,
	H2_PUSH_DEFAULT,
	H2_PUSH_HEAD,
	H2_PUSH_FAST_LOAD,
	} h2_push_policy;

	typedef enum {
	H2_SESSION_ST_INIT, /* send initial SETTINGS, etc. */
	H2_SESSION_ST_DONE, /* finished, connection close */
	H2_SESSION_ST_IDLE, /* nothing to write, expecting data inc */
	H2_SESSION_ST_BUSY, /* read/write without stop */
	H2_SESSION_ST_WAIT, /* waiting for c1 incoming + c2s output */
	H2_SESSION_ST_CLEANUP, /* pool is being cleaned up */
	} h2_session_state;

	typedef struct h2_session_props {
	int accepted_max; /* the highest remote stream id was/will be handled */
	int completed_max; /* the highest remote stream completed */
	int emitted_count; /* the number of local streams sent */
	int emitted_max; /* the highest local stream id sent */
	int error; /* the last session error encountered */
	const char error_msg; / the short message given on the error */
	unsigned int accepting : 1; /* if the session is accepting new streams */
	unsigned int shutdown : 1; /* if the final GOAWAY has been sent */
	} h2_session_props;

	typedef enum h2_stream_state_t {
	H2_SS_IDLE,
	H2_SS_RSVD_R,
	H2_SS_RSVD_L,
	H2_SS_OPEN,
	H2_SS_CLOSED_R,
	H2_SS_CLOSED_L,
	H2_SS_CLOSED,
	H2_SS_CLEANUP,
	H2_SS_MAX
	} h2_stream_state_t;

	typedef enum {
	H2_SEV_CLOSED_L,
	H2_SEV_CLOSED_R,
	H2_SEV_CANCELLED,
	H2_SEV_EOS_SENT,
	H2_SEV_IN_ERROR,
	H2_SEV_IN_DATA_PENDING,
	H2_SEV_OUT_C1_BLOCK,
	} h2_stream_event_t;


	/* h2_request is the transformer of HTTP2 streams into HTTP/1.1 internal
	* format that will be fed to various httpd input filters to finally
	* become a request_rec to be handled by soemone.
	*/
	typedef struct h2_request h2_request;
	struct h2_request {
	const char method; / pseudo header values, see ch. 8.1.2.3 */
	const char *scheme;
	const char *authority;
	const char *path;
	apr_table_t *headers;

	apr_time_t request_time;
	apr_off_t raw_bytes; /* RAW network bytes that generated this request - if known. */
	int http_status; /* Store a possible HTTP status code that gets
	* defined before creating the dummy HTTP/1.1
	* request e.g. due to an error already
	* detected.
	*/
	};

	/*
	* A possible HTTP status code is not defined yet. See the http_status field
	* in struct h2_request above for further explanation.
	*/
	#define H2_HTTP_STATUS_UNSET (0)

	typedef apr_status_t h2_io_data_cb(void ctx, const char data, apr_off_t len);

	typedef int h2_stream_pri_cmp_fn(int stream_id1, int stream_id2, void *session);
	typedef struct h2_stream h2_stream_get_fn(struct h2_session session, int stream_id);

	/* Note key to attach stream id to conn_rec/request_rec instances */
	#define H2_HDR_CONFORMANCE "http2-hdr-conformance"
	#define H2_HDR_CONFORMANCE_UNSAFE "unsafe"
	#define H2_PUSH_MODE_NOTE "http2-push-mode"


	#if AP_MODULE_MAGIC_AT_LEAST(20211221, 6)
	#define AP_HAS_RESPONSE_BUCKETS 1

	#else /* AP_MODULE_MAGIC_AT_LEAST(20211221, 6) */
	#define AP_HAS_RESPONSE_BUCKETS 0

	#endif /* else AP_MODULE_MAGIC_AT_LEAST(20211221, 6) */

	#endif /* defined(__mod_h2__h2__) */