MINOR: h2: centralize all HTTP/2 protocol elements and constants
These constants from RFC7540 will be centralized into common/h2.h for
use by the future h2 mux and other places.
diff --git a/include/common/h2.h b/include/common/h2.h
new file mode 100644
index 0000000..0521b11
--- /dev/null
+++ b/include/common/h2.h
@@ -0,0 +1,135 @@
+/*
+ * include/common/h2.h
+ * This file contains types and macros used for the HTTP/2 protocol
+ *
+ * Copyright (C) 2000-2017 Willy Tarreau - w@1wt.eu
+ * Copyright (C) 2017 HAProxy Technologies
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation, version 2.1
+ * exclusively.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef _COMMON_H2_H
+#define _COMMON_H2_H
+
+#include <common/config.h>
+
+
+/* frame types, from the standard */
+enum h2_ft {
+ H2_FT_DATA = 0x00, // RFC7540 #6.1
+ H2_FT_HEADERS = 0x01, // RFC7540 #6.2
+ H2_FT_PRIORITY = 0x02, // RFC7540 #6.3
+ H2_FT_RST_STREAM = 0x03, // RFC7540 #6.4
+ H2_FT_SETTINGS = 0x04, // RFC7540 #6.5
+ H2_FT_PUSH_PROMISE = 0x05, // RFC7540 #6.6
+ H2_FT_PING = 0x06, // RFC7540 #6.7
+ H2_FT_GOAWAY = 0x07, // RFC7540 #6.8
+ H2_FT_WINDOW_UPDATE = 0x08, // RFC7540 #6.9
+ H2_FT_CONTINUATION = 0x09, // RFC7540 #6.10
+ H2_FT_ENTRIES /* must be last */
+} __attribute__((packed));
+
+/* flags defined for each frame type */
+
+// RFC7540 #6.1
+#define H2_F_DATA_END_STREAM 0x01
+#define H2_F_DATA_PADDED 0x08
+
+// RFC7540 #6.2
+#define H2_F_HEADERS_END_STREAM 0x01
+#define H2_F_HEADERS_END_HEADERS 0x04
+#define H2_F_HEADERS_PADDED 0x08
+#define H2_F_HEADERS_PRIORITY 0x20
+
+// RFC7540 #6.3 : PRIORITY defines no flags
+// RFC7540 #6.4 : RST_STREAM defines no flags
+
+// RFC7540 #6.5
+#define H2_F_SETTINGS_ACK 0x01
+
+// RFC7540 #6.6
+#define H2_F_PUSH_PROMISE_END_HEADERS 0x04
+#define H2_F_PUSH_PROMISE_PADDED 0x08
+
+// RFC7540 #6.7
+#define H2_F_PING_ACK 0x01
+
+// RFC7540 #6.8 : GOAWAY defines no flags
+// RFC7540 #6.9 : WINDOW_UPDATE defines no flags
+
+/* HTTP/2 error codes - RFC7540 #7 */
+enum h2_err {
+ H2_ERR_NO_ERROR = 0x0,
+ H2_ERR_PROTOCOL_ERROR = 0x1,
+ H2_ERR_INTERNAL_ERROR = 0x2,
+ H2_ERR_FLOW_CONTROL_ERROR = 0x3,
+ H2_ERR_SETTINGS_TIMEOUT = 0x4,
+ H2_ERR_STREAM_CLOSED = 0x5,
+ H2_ERR_FRAME_SIZE_ERROR = 0x6,
+ H2_ERR_REFUSED_STREAM = 0x7,
+ H2_ERR_CANCEL = 0x8,
+ H2_ERR_COMPRESSION_ERROR = 0x9,
+ H2_ERR_CONNECT_ERROR = 0xa,
+ H2_ERR_ENHANCE_YOUR_CALM = 0xb,
+ H2_ERR_INADEQUATE_SECURITY = 0xc,
+ H2_ERR_HTTP_1_1_REQUIRED = 0xd,
+} __attribute__((packed));
+
+// RFC7540 #11.3 : Settings Registry
+#define H2_SETTINGS_HEADER_TABLE_SIZE 0x0001
+#define H2_SETTINGS_ENABLE_PUSH 0x0002
+#define H2_SETTINGS_MAX_CONCURRENT_STREAMS 0x0003
+#define H2_SETTINGS_INITIAL_WINDOW_SIZE 0x0004
+#define H2_SETTINGS_MAX_FRAME_SIZE 0x0005
+#define H2_SETTINGS_MAX_HEADER_LIST_SIZE 0x0006
+
+
+/* some protocol constants */
+
+// PRI * HTTP/2.0\r\n\r\nSM\r\n\r\n
+#define H2_CONN_PREFACE \
+ "\x50\x52\x49\x20\x2a\x20\x48\x54" \
+ "\x54\x50\x2f\x32\x2e\x30\x0d\x0a" \
+ "\x0d\x0a\x53\x4d\x0d\x0a\x0d\x0a"
+
+/*
+ * Some helpful debugging functions.
+ */
+
+/* returns the frame type as a string */
+static inline const char *h2_ft_str(int type)
+{
+ switch (type) {
+ case H2_FT_DATA : return "DATA";
+ case H2_FT_HEADERS : return "HEADERS";
+ case H2_FT_PRIORITY : return "PRIORITY";
+ case H2_FT_RST_STREAM : return "RST_STREAM";
+ case H2_FT_SETTINGS : return "SETTINGS";
+ case H2_FT_PUSH_PROMISE : return "PUSH_PROMISE";
+ case H2_FT_PING : return "PING";
+ case H2_FT_GOAWAY : return "GOAWAY";
+ case H2_FT_WINDOW_UPDATE : return "WINDOW_UPDATE";
+ default : return "_UNKNOWN_";
+ }
+}
+
+#endif /* _COMMON_H2_H */
+
+/*
+ * Local variables:
+ * c-indent-level: 8
+ * c-basic-offset: 8
+ * End:
+ */