nghttp2/lib/nghttp2_hd.h

441 lines
15 KiB
C

/*
* nghttp2 - HTTP/2 C Library
*
* Copyright (c) 2013 Tatsuhiro Tsujikawa
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#ifndef NGHTTP2_HD_H
#define NGHTTP2_HD_H
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif /* HAVE_CONFIG_H */
#include <nghttp2/nghttp2.h>
#include "nghttp2_hd_huffman.h"
#include "nghttp2_buf.h"
#include "nghttp2_mem.h"
#define NGHTTP2_HD_DEFAULT_MAX_BUFFER_SIZE NGHTTP2_DEFAULT_HEADER_TABLE_SIZE
#define NGHTTP2_HD_ENTRY_OVERHEAD 32
/* The maximum length of one name/value pair. This is the sum of the
length of name and value. This is not specified by the spec. We
just chose the arbitrary size */
#define NGHTTP2_HD_MAX_NV 65536
/* Default size of maximum table buffer size for encoder. Even if
remote decoder notifies larger buffer size for its decoding,
encoder only uses the memory up to this value. */
#define NGHTTP2_HD_DEFAULT_MAX_DEFLATE_BUFFER_SIZE (1 << 12)
/* Exported for unit test */
#define NGHTTP2_STATIC_TABLE_LENGTH 61
/* Generated by genlibtokenlookup.py */
typedef enum {
NGHTTP2_TOKEN__AUTHORITY = 0,
NGHTTP2_TOKEN__METHOD = 1,
NGHTTP2_TOKEN__PATH = 3,
NGHTTP2_TOKEN__SCHEME = 5,
NGHTTP2_TOKEN__STATUS = 7,
NGHTTP2_TOKEN_ACCEPT_CHARSET = 14,
NGHTTP2_TOKEN_ACCEPT_ENCODING = 15,
NGHTTP2_TOKEN_ACCEPT_LANGUAGE = 16,
NGHTTP2_TOKEN_ACCEPT_RANGES = 17,
NGHTTP2_TOKEN_ACCEPT = 18,
NGHTTP2_TOKEN_ACCESS_CONTROL_ALLOW_ORIGIN = 19,
NGHTTP2_TOKEN_AGE = 20,
NGHTTP2_TOKEN_ALLOW = 21,
NGHTTP2_TOKEN_AUTHORIZATION = 22,
NGHTTP2_TOKEN_CACHE_CONTROL = 23,
NGHTTP2_TOKEN_CONTENT_DISPOSITION = 24,
NGHTTP2_TOKEN_CONTENT_ENCODING = 25,
NGHTTP2_TOKEN_CONTENT_LANGUAGE = 26,
NGHTTP2_TOKEN_CONTENT_LENGTH = 27,
NGHTTP2_TOKEN_CONTENT_LOCATION = 28,
NGHTTP2_TOKEN_CONTENT_RANGE = 29,
NGHTTP2_TOKEN_CONTENT_TYPE = 30,
NGHTTP2_TOKEN_COOKIE = 31,
NGHTTP2_TOKEN_DATE = 32,
NGHTTP2_TOKEN_ETAG = 33,
NGHTTP2_TOKEN_EXPECT = 34,
NGHTTP2_TOKEN_EXPIRES = 35,
NGHTTP2_TOKEN_FROM = 36,
NGHTTP2_TOKEN_HOST = 37,
NGHTTP2_TOKEN_IF_MATCH = 38,
NGHTTP2_TOKEN_IF_MODIFIED_SINCE = 39,
NGHTTP2_TOKEN_IF_NONE_MATCH = 40,
NGHTTP2_TOKEN_IF_RANGE = 41,
NGHTTP2_TOKEN_IF_UNMODIFIED_SINCE = 42,
NGHTTP2_TOKEN_LAST_MODIFIED = 43,
NGHTTP2_TOKEN_LINK = 44,
NGHTTP2_TOKEN_LOCATION = 45,
NGHTTP2_TOKEN_MAX_FORWARDS = 46,
NGHTTP2_TOKEN_PROXY_AUTHENTICATE = 47,
NGHTTP2_TOKEN_PROXY_AUTHORIZATION = 48,
NGHTTP2_TOKEN_RANGE = 49,
NGHTTP2_TOKEN_REFERER = 50,
NGHTTP2_TOKEN_REFRESH = 51,
NGHTTP2_TOKEN_RETRY_AFTER = 52,
NGHTTP2_TOKEN_SERVER = 53,
NGHTTP2_TOKEN_SET_COOKIE = 54,
NGHTTP2_TOKEN_STRICT_TRANSPORT_SECURITY = 55,
NGHTTP2_TOKEN_TRANSFER_ENCODING = 56,
NGHTTP2_TOKEN_USER_AGENT = 57,
NGHTTP2_TOKEN_VARY = 58,
NGHTTP2_TOKEN_VIA = 59,
NGHTTP2_TOKEN_WWW_AUTHENTICATE = 60,
NGHTTP2_TOKEN_TE,
NGHTTP2_TOKEN_CONNECTION,
NGHTTP2_TOKEN_KEEP_ALIVE,
NGHTTP2_TOKEN_PROXY_CONNECTION,
NGHTTP2_TOKEN_UPGRADE
} nghttp2_token;
typedef enum {
NGHTTP2_HD_FLAG_NONE = 0,
/* Indicates name was dynamically allocated and must be freed */
NGHTTP2_HD_FLAG_NAME_ALLOC = 1,
/* Indicates value was dynamically allocated and must be freed */
NGHTTP2_HD_FLAG_VALUE_ALLOC = 1 << 1,
/* Indicates that the name was gifted to the entry and no copying
necessary. */
NGHTTP2_HD_FLAG_NAME_GIFT = 1 << 2,
/* Indicates that the value was gifted to the entry and no copying
necessary. */
NGHTTP2_HD_FLAG_VALUE_GIFT = 1 << 3
} nghttp2_hd_flags;
struct nghttp2_hd_entry;
typedef struct nghttp2_hd_entry nghttp2_hd_entry;
struct nghttp2_hd_entry {
nghttp2_nv nv;
/* The next entry which shares same bucket in hash table. */
nghttp2_hd_entry *next;
/* The sequence number. We will increment it by one whenever we
store nghttp2_hd_entry to dynamic header table. */
uint32_t seq;
/* The hash value for header name (nv.name). */
uint32_t hash;
/* nghttp2_token value for nv.name. It could be -1 if we have no
token for that header field name. */
int token;
/* Reference count */
uint8_t ref;
uint8_t flags;
};
typedef struct {
nghttp2_hd_entry **buffer;
size_t mask;
size_t first;
size_t len;
} nghttp2_hd_ringbuf;
typedef enum {
NGHTTP2_HD_OPCODE_NONE,
NGHTTP2_HD_OPCODE_INDEXED,
NGHTTP2_HD_OPCODE_NEWNAME,
NGHTTP2_HD_OPCODE_INDNAME
} nghttp2_hd_opcode;
typedef enum {
NGHTTP2_HD_STATE_EXPECT_TABLE_SIZE,
NGHTTP2_HD_STATE_INFLATE_START,
NGHTTP2_HD_STATE_OPCODE,
NGHTTP2_HD_STATE_READ_TABLE_SIZE,
NGHTTP2_HD_STATE_READ_INDEX,
NGHTTP2_HD_STATE_NEWNAME_CHECK_NAMELEN,
NGHTTP2_HD_STATE_NEWNAME_READ_NAMELEN,
NGHTTP2_HD_STATE_NEWNAME_READ_NAMEHUFF,
NGHTTP2_HD_STATE_NEWNAME_READ_NAME,
NGHTTP2_HD_STATE_CHECK_VALUELEN,
NGHTTP2_HD_STATE_READ_VALUELEN,
NGHTTP2_HD_STATE_READ_VALUEHUFF,
NGHTTP2_HD_STATE_READ_VALUE
} nghttp2_hd_inflate_state;
typedef enum {
NGHTTP2_HD_WITH_INDEXING,
NGHTTP2_HD_WITHOUT_INDEXING,
NGHTTP2_HD_NEVER_INDEXING
} nghttp2_hd_indexing_mode;
typedef struct {
/* dynamic header table */
nghttp2_hd_ringbuf hd_table;
/* Memory allocator */
nghttp2_mem *mem;
/* Abstract buffer size of hd_table as described in the spec. This
is the sum of length of name/value in hd_table +
NGHTTP2_HD_ENTRY_OVERHEAD bytes overhead per each entry. */
size_t hd_table_bufsize;
/* The effective header table size. */
size_t hd_table_bufsize_max;
/* Next sequence number for nghttp2_hd_entry */
uint32_t next_seq;
/* If inflate/deflate error occurred, this value is set to 1 and
further invocation of inflate/deflate will fail with
NGHTTP2_ERR_HEADER_COMP. */
uint8_t bad;
} nghttp2_hd_context;
#define HD_MAP_SIZE 128
typedef struct { nghttp2_hd_entry *table[HD_MAP_SIZE]; } nghttp2_hd_map;
struct nghttp2_hd_deflater {
nghttp2_hd_context ctx;
nghttp2_hd_map map;
/* The upper limit of the header table size the deflater accepts. */
size_t deflate_hd_table_bufsize_max;
/* Minimum header table size notified in the next context update */
size_t min_hd_table_bufsize_max;
/* If nonzero, send header table size using encoding context update
in the next deflate process */
uint8_t notify_table_size_change;
};
struct nghttp2_hd_inflater {
nghttp2_hd_context ctx;
/* header buffer */
nghttp2_bufs nvbufs;
/* Stores current state of huffman decoding */
nghttp2_hd_huff_decode_context huff_decode_ctx;
/* Pointer to the nghttp2_hd_entry which is used current header
emission. This is required because in some cases the
ent_keep->ref == 0 and we have to keep track of it. */
nghttp2_hd_entry *ent_keep;
/* Pointer to the name/value pair buffer which is used in the
current header emission. */
uint8_t *nv_keep;
/* The number of bytes to read */
size_t left;
/* The index in indexed repr or indexed name */
size_t index;
/* The length of new name encoded in literal. For huffman encoded
string, this is the length after it is decoded. */
size_t newnamelen;
/* The maximum header table size the inflater supports. This is the
same value transmitted in SETTINGS_HEADER_TABLE_SIZE */
size_t settings_hd_table_bufsize_max;
/* The number of next shift to decode integer */
size_t shift;
nghttp2_hd_opcode opcode;
nghttp2_hd_inflate_state state;
/* nonzero if string is huffman encoded */
uint8_t huffman_encoded;
/* nonzero if deflater requires that current entry is indexed */
uint8_t index_required;
/* nonzero if deflater requires that current entry must not be
indexed */
uint8_t no_index;
};
/*
* Initializes the |ent| members. If NGHTTP2_HD_FLAG_NAME_ALLOC bit
* set in the |flags|, the content pointed by the |name| with length
* |namelen| is copied. Likewise, if NGHTTP2_HD_FLAG_VALUE_ALLOC bit
* set in the |flags|, the content pointed by the |value| with length
* |valuelen| is copied. The |token| is enum number looked up by
* |name|. It could be -1 if we don't have that enum value.
*
* This function returns 0 if it succeeds, or one of the following
* negative error codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory.
*/
int nghttp2_hd_entry_init(nghttp2_hd_entry *ent, uint8_t flags, uint8_t *name,
size_t namelen, uint8_t *value, size_t valuelen,
int token, nghttp2_mem *mem);
void nghttp2_hd_entry_free(nghttp2_hd_entry *ent, nghttp2_mem *mem);
/*
* Initializes |deflater| for deflating name/values pairs.
*
* The encoder only uses up to
* NGHTTP2_HD_DEFAULT_MAX_DEFLATE_BUFFER_SIZE bytes for header table
* even if the larger value is specified later in
* nghttp2_hd_change_table_size().
*
* This function returns 0 if it succeeds, or one of the following
* negative error codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory.
*/
int nghttp2_hd_deflate_init(nghttp2_hd_deflater *deflater, nghttp2_mem *mem);
/*
* Initializes |deflater| for deflating name/values pairs.
*
* The encoder only uses up to |deflate_hd_table_bufsize_max| bytes
* for header table even if the larger value is specified later in
* nghttp2_hd_change_table_size().
*
* This function returns 0 if it succeeds, or one of the following
* negative error codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory.
*/
int nghttp2_hd_deflate_init2(nghttp2_hd_deflater *deflater,
size_t deflate_hd_table_bufsize_max,
nghttp2_mem *mem);
/*
* Deallocates any resources allocated for |deflater|.
*/
void nghttp2_hd_deflate_free(nghttp2_hd_deflater *deflater);
/*
* Deflates the |nva|, which has the |nvlen| name/value pairs, into
* the |bufs|.
*
* This function expands |bufs| as necessary to store the result. If
* buffers is full and the process still requires more space, this
* funtion fails and returns NGHTTP2_ERR_HEADER_COMP.
*
* After this function returns, it is safe to delete the |nva|.
*
* This function returns 0 if it succeeds, or one of the following
* negative error codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory.
* NGHTTP2_ERR_HEADER_COMP
* Deflation process has failed.
* NGHTTP2_ERR_BUFFER_ERROR
* Out of buffer space.
*/
int nghttp2_hd_deflate_hd_bufs(nghttp2_hd_deflater *deflater,
nghttp2_bufs *bufs, const nghttp2_nv *nva,
size_t nvlen);
/*
* Initializes |inflater| for inflating name/values pairs.
*
* This function returns 0 if it succeeds, or one of the following
* negative error codes:
*
* :enum:`NGHTTP2_ERR_NOMEM`
* Out of memory.
*/
int nghttp2_hd_inflate_init(nghttp2_hd_inflater *inflater, nghttp2_mem *mem);
/*
* Deallocates any resources allocated for |inflater|.
*/
void nghttp2_hd_inflate_free(nghttp2_hd_inflater *inflater);
/*
* Similar to nghttp2_hd_inflate_hd(), but this takes additional
* output parameter |token|. On successful header emission, it
* contains nghttp2_token value for nv_out->name. It could be -1 if
* we don't have enum value for the name. Other than that return
* values and semantics are the same as nghttp2_hd_inflate_hd().
*/
ssize_t nghttp2_hd_inflate_hd2(nghttp2_hd_inflater *inflater,
nghttp2_nv *nv_out, int *inflate_flags,
int *token, uint8_t *in, size_t inlen,
int in_final);
/* For unittesting purpose */
int nghttp2_hd_emit_indname_block(nghttp2_bufs *bufs, size_t index,
nghttp2_nv *nv, int indexing_mode);
/* For unittesting purpose */
int nghttp2_hd_emit_newname_block(nghttp2_bufs *bufs, nghttp2_nv *nv,
int indexing_mode);
/* For unittesting purpose */
int nghttp2_hd_emit_table_size(nghttp2_bufs *bufs, size_t table_size);
/* For unittesting purpose */
nghttp2_hd_entry *nghttp2_hd_table_get(nghttp2_hd_context *context,
size_t index);
/* For unittesting purpose */
ssize_t nghttp2_hd_decode_length(uint32_t *res, size_t *shift_ptr, int *final,
uint32_t initial, size_t shift, uint8_t *in,
uint8_t *last, size_t prefix);
/* Huffman encoding/decoding functions */
/*
* Counts the required bytes to encode |src| with length |len|.
*
* This function returns the number of required bytes to encode given
* data, including padding of prefix of terminal symbol code. This
* function always succeeds.
*/
size_t nghttp2_hd_huff_encode_count(const uint8_t *src, size_t len);
/*
* Encodes the given data |src| with length |srclen| to the |bufs|.
* This function expands extra buffers in |bufs| if necessary.
*
* This function returns 0 if it succeeds, or one of the following
* negative error codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory.
* NGHTTP2_ERR_BUFFER_ERROR
* Out of buffer space.
*/
int nghttp2_hd_huff_encode(nghttp2_bufs *bufs, const uint8_t *src,
size_t srclen);
void nghttp2_hd_huff_decode_context_init(nghttp2_hd_huff_decode_context *ctx);
/*
* Decodes the given data |src| with length |srclen|. The |ctx| must
* be initialized by nghttp2_hd_huff_decode_context_init(). The result
* will be added to |dest|. This function may expand |dest| as
* needed. The caller is responsible to release the memory of |dest|
* by calling nghttp2_bufs_free().
*
* The caller must set the |final| to nonzero if the given input is
* the final block.
*
* This function returns the number of read bytes from the |in|.
*
* If this function fails, it returns one of the following negative
* return codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory.
* NGHTTP2_ERR_BUFFER_ERROR
* Maximum buffer capacity size exceeded.
* NGHTTP2_ERR_HEADER_COMP
* Decoding process has failed.
*/
ssize_t nghttp2_hd_huff_decode(nghttp2_hd_huff_decode_context *ctx,
nghttp2_bufs *bufs, const uint8_t *src,
size_t srclen, int final);
#endif /* NGHTTP2_HD_H */