nghttp2/lib/nghttp2_hd.c

1404 lines
42 KiB
C

/*
* nghttp2 - HTTP/2.0 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.
*/
#include "nghttp2_hd.h"
#include <string.h>
#include <assert.h>
#include "nghttp2_frame.h"
#include "nghttp2_helper.h"
/* Make scalar initialization form of nghttp2_nv */
#define MAKE_NV(N, V) \
{ { (uint8_t*)N, (uint8_t*)V, sizeof(N) - 1, sizeof(V) - 1 }, \
1, NGHTTP2_HD_FLAG_NONE }
static nghttp2_hd_entry static_table[] = {
/* 0 */ MAKE_NV(":authority", ""),
/* 1 */ MAKE_NV(":method", "GET"),
/* 2 */ MAKE_NV(":method", "POST"),
/* 3 */ MAKE_NV(":path", "/"),
/* 4 */ MAKE_NV(":path", "/index.html"),
/* 5 */ MAKE_NV(":scheme", "http"),
/* 6 */ MAKE_NV(":scheme", "https"),
/* 7 */ MAKE_NV(":status", "200"),
/* 8 */ MAKE_NV(":status", "500"),
/* 9 */ MAKE_NV(":status", "404"),
/* 10 */ MAKE_NV(":status", "403"),
/* 11 */ MAKE_NV(":status", "400"),
/* 12 */ MAKE_NV(":status", "401"),
/* 13 */ MAKE_NV("accept-charset", ""),
/* 14 */ MAKE_NV("accept-encoding", ""),
/* 15 */ MAKE_NV("accept-language", ""),
/* 16 */ MAKE_NV("accept-ranges", ""),
/* 17 */ MAKE_NV("accept", ""),
/* 18 */ MAKE_NV("access-control-allow-origin", ""),
/* 19 */ MAKE_NV("age", ""),
/* 20 */ MAKE_NV("allow", ""),
/* 21 */ MAKE_NV("authorization", ""),
/* 22 */ MAKE_NV("cache-control", ""),
/* 23 */ MAKE_NV("content-disposition", ""),
/* 24 */ MAKE_NV("content-encoding", ""),
/* 25 */ MAKE_NV("content-language", ""),
/* 26 */ MAKE_NV("content-length", ""),
/* 27 */ MAKE_NV("content-location", ""),
/* 28 */ MAKE_NV("content-range", ""),
/* 29 */ MAKE_NV("content-type", ""),
/* 30 */ MAKE_NV("cookie", ""),
/* 31 */ MAKE_NV("date", ""),
/* 32 */ MAKE_NV("etag", ""),
/* 33 */ MAKE_NV("expect", ""),
/* 34 */ MAKE_NV("expires", ""),
/* 35 */ MAKE_NV("from", ""),
/* 36 */ MAKE_NV("if-match", ""),
/* 37 */ MAKE_NV("if-modified-since", ""),
/* 38 */ MAKE_NV("if-none-match", ""),
/* 39 */ MAKE_NV("if-range", ""),
/* 40 */ MAKE_NV("if-unmodified-since", ""),
/* 41 */ MAKE_NV("last-modified", ""),
/* 42 */ MAKE_NV("link", ""),
/* 43 */ MAKE_NV("location", ""),
/* 44 */ MAKE_NV("max-forwards", ""),
/* 45 */ MAKE_NV("proxy-authenticate", ""),
/* 46 */ MAKE_NV("proxy-authorization", ""),
/* 47 */ MAKE_NV("range", ""),
/* 48 */ MAKE_NV("referer", ""),
/* 49 */ MAKE_NV("refresh", ""),
/* 50 */ MAKE_NV("retry-after", ""),
/* 51 */ MAKE_NV("server", ""),
/* 52 */ MAKE_NV("set-cookie", ""),
/* 53 */ MAKE_NV("strict-transport-security", ""),
/* 54 */ MAKE_NV("transfer-encoding", ""),
/* 55 */ MAKE_NV("user-agent", ""),
/* 56 */ MAKE_NV("vary", ""),
/* 57 */ MAKE_NV("via", ""),
/* 58 */ MAKE_NV("www-authenticate", "")
};
const static size_t STATIC_TABLE_LENGTH =
sizeof(static_table)/sizeof(static_table[0]);
typedef struct {
nghttp2_nv *nva;
size_t nvacap;
size_t nvlen;
} nghttp2_nva_out;
int nghttp2_hd_entry_init(nghttp2_hd_entry *ent, uint8_t flags,
uint8_t *name, uint16_t namelen,
uint8_t *value, uint16_t valuelen)
{
int rv = 0;
if((flags & NGHTTP2_HD_FLAG_NAME_ALLOC) &&
(flags & NGHTTP2_HD_FLAG_NAME_GIFT) == 0) {
if(namelen == 0) {
/* We should not allow empty header field name */
ent->nv.name = NULL;
} else {
ent->nv.name = nghttp2_memdup(name, namelen);
if(ent->nv.name == NULL) {
rv = NGHTTP2_ERR_NOMEM;
goto fail;
}
}
} else {
ent->nv.name = name;
}
if((flags & NGHTTP2_HD_FLAG_VALUE_ALLOC) &&
(flags & NGHTTP2_HD_FLAG_VALUE_GIFT) == 0) {
if(valuelen == 0) {
ent->nv.value = NULL;
} else {
ent->nv.value = nghttp2_memdup(value, valuelen);
if(ent->nv.value == NULL) {
rv = NGHTTP2_ERR_NOMEM;
goto fail2;
}
}
} else {
ent->nv.value = value;
}
ent->nv.namelen = namelen;
ent->nv.valuelen = valuelen;
ent->ref = 1;
ent->flags = flags;
return 0;
fail2:
if(flags & NGHTTP2_HD_FLAG_NAME_ALLOC) {
free(ent->nv.name);
}
fail:
return rv;
}
void nghttp2_hd_entry_free(nghttp2_hd_entry *ent)
{
assert(ent->ref == 0);
if(ent->flags & NGHTTP2_HD_FLAG_NAME_ALLOC) {
free(ent->nv.name);
}
if(ent->flags & NGHTTP2_HD_FLAG_VALUE_ALLOC) {
free(ent->nv.value);
}
}
static int nghttp2_hd_ringbuf_init(nghttp2_hd_ringbuf *ringbuf,
size_t bufsize)
{
size_t size;
for(size = 1; size < bufsize; size <<= 1);
ringbuf->buffer = malloc(sizeof(nghttp2_hd_entry*)*size);
if(ringbuf->buffer == NULL) {
return NGHTTP2_ERR_NOMEM;
}
ringbuf->mask = size - 1;
ringbuf->first = 0;
ringbuf->len = 0;
return 0;
}
static nghttp2_hd_entry* nghttp2_hd_ringbuf_get(nghttp2_hd_ringbuf *ringbuf,
size_t index)
{
assert(index < ringbuf->len);
return ringbuf->buffer[(ringbuf->first + index) & ringbuf->mask];
}
static int nghttp2_hd_ringbuf_reserve(nghttp2_hd_ringbuf *ringbuf,
size_t bufsize)
{
size_t i;
size_t size;
nghttp2_hd_entry **buffer;
if(ringbuf->mask + 1 >= bufsize) {
return 0;
}
for(size = 1; size < bufsize; size <<= 1);
buffer = malloc(sizeof(nghttp2_hd_entry*) * size);
if(buffer == NULL) {
return NGHTTP2_ERR_NOMEM;
}
for(i = 0; i < ringbuf->len; ++i) {
buffer[i] = nghttp2_hd_ringbuf_get(ringbuf, i);
}
free(ringbuf->buffer);
ringbuf->buffer = buffer;
ringbuf->mask = size - 1;
ringbuf->first = 0;
return 0;
}
static void nghttp2_hd_ringbuf_free(nghttp2_hd_ringbuf *ringbuf)
{
size_t i;
if(ringbuf == NULL) {
return;
}
for(i = 0; i < ringbuf->len; ++i) {
nghttp2_hd_entry *ent = nghttp2_hd_ringbuf_get(ringbuf, i);
--ent->ref;
nghttp2_hd_entry_free(ent);
free(ent);
}
free(ringbuf->buffer);
}
static size_t nghttp2_hd_ringbuf_push_front(nghttp2_hd_ringbuf *ringbuf,
nghttp2_hd_entry *ent)
{
assert(ringbuf->len + 1 <= ringbuf->mask);
ringbuf->buffer[--ringbuf->first & ringbuf->mask] = ent;
++ringbuf->len;
return 0;
}
static void nghttp2_hd_ringbuf_pop_back(nghttp2_hd_ringbuf *ringbuf)
{
assert(ringbuf->len > 0);
--ringbuf->len;
}
static int nghttp2_hd_context_init(nghttp2_hd_context *context,
nghttp2_hd_role role,
nghttp2_hd_side side,
size_t local_hd_table_bufsize_max)
{
int rv;
context->role = role;
context->side = side;
context->bad = 0;
context->hd_table_bufsize_max = NGHTTP2_HD_DEFAULT_MAX_BUFFER_SIZE;
rv = nghttp2_hd_ringbuf_init
(&context->hd_table,
context->hd_table_bufsize_max/NGHTTP2_HD_ENTRY_OVERHEAD);
if(rv != 0) {
return rv;
}
if(role == NGHTTP2_HD_ROLE_INFLATE) {
context->emit_set = malloc(sizeof(nghttp2_hd_entry*)*
NGHTTP2_INITIAL_EMIT_SET_SIZE);
if(context->emit_set == NULL) {
goto fail;
}
memset(context->emit_set, 0, sizeof(nghttp2_hd_entry*)*
NGHTTP2_INITIAL_EMIT_SET_SIZE);
context->emit_set_capacity = NGHTTP2_INITIAL_EMIT_SET_SIZE;
context->buf_track = malloc(sizeof(uint8_t*)*
NGHTTP2_INITIAL_BUF_TRACK_SIZE);
if(context->buf_track == NULL) {
goto fail;
}
context->buf_track_capacity = NGHTTP2_INITIAL_BUF_TRACK_SIZE;
} else {
context->emit_set = NULL;
context->emit_set_capacity = 0;
context->buf_track = NULL;
context->buf_track_capacity = 0;
}
context->local_hd_table_bufsize_max = local_hd_table_bufsize_max;
context->local_hd_table_bufsize = 0;
context->local_hd_tablelen = 0;
context->emit_setlen = 0;
context->buf_tracklen = 0;
context->hd_table_bufsize = 0;
return 0;
fail:
free(context->buf_track);
free(context->emit_set);
nghttp2_hd_ringbuf_free(&context->hd_table);
return NGHTTP2_ERR_NOMEM;
}
int nghttp2_hd_deflate_init(nghttp2_hd_context *deflater, nghttp2_hd_side side)
{
return nghttp2_hd_context_init(deflater, NGHTTP2_HD_ROLE_DEFLATE, side,
NGHTTP2_HD_DEFAULT_LOCAL_MAX_BUFFER_SIZE);
}
int nghttp2_hd_deflate_init2(nghttp2_hd_context *deflater,
nghttp2_hd_side side,
size_t local_hd_table_bufsize_max)
{
return nghttp2_hd_context_init(deflater, NGHTTP2_HD_ROLE_DEFLATE, side,
local_hd_table_bufsize_max);
}
int nghttp2_hd_inflate_init(nghttp2_hd_context *inflater, nghttp2_hd_side side)
{
return nghttp2_hd_context_init(inflater, NGHTTP2_HD_ROLE_INFLATE, side, 0);
}
static void nghttp2_hd_context_free(nghttp2_hd_context *context)
{
size_t i;
for(i = 0; i < context->buf_tracklen; ++i) {
free(context->buf_track[i]);
}
free(context->buf_track);
for(i = 0; i < context->emit_setlen; ++i) {
nghttp2_hd_entry *ent = context->emit_set[i];
if(--ent->ref == 0) {
nghttp2_hd_entry_free(ent);
free(ent);
}
}
free(context->emit_set);
nghttp2_hd_ringbuf_free(&context->hd_table);
}
void nghttp2_hd_deflate_free(nghttp2_hd_context *deflater)
{
nghttp2_hd_context_free(deflater);
}
void nghttp2_hd_inflate_free(nghttp2_hd_context *inflater)
{
nghttp2_hd_context_free(inflater);
}
static size_t entry_room(size_t namelen, size_t valuelen)
{
return NGHTTP2_HD_ENTRY_OVERHEAD + namelen + valuelen;
}
static int add_nva(nghttp2_nva_out *nva_out_ptr,
uint8_t *name, uint16_t namelen,
uint8_t *value, uint16_t valuelen)
{
nghttp2_nv *nv;
if(nva_out_ptr->nvacap == nva_out_ptr->nvlen) {
size_t newcap = nva_out_ptr->nvacap == 0 ? 16 : nva_out_ptr->nvacap * 2;
nghttp2_nv *new_nva = realloc(nva_out_ptr->nva, sizeof(nghttp2_nv)*newcap);
if(new_nva == NULL) {
return NGHTTP2_ERR_NOMEM;
}
nva_out_ptr->nva = new_nva;
nva_out_ptr->nvacap = newcap;
}
nv = &nva_out_ptr->nva[nva_out_ptr->nvlen++];
nv->name = name;
nv->namelen = namelen;
nv->value = value;
nv->valuelen = valuelen;
return 0;
}
static int track_decode_buf(nghttp2_hd_context *context, uint8_t *buf)
{
if(context->buf_tracklen == context->buf_track_capacity) {
return NGHTTP2_ERR_HEADER_COMP;
}
context->buf_track[context->buf_tracklen++] = buf;
return 0;
}
static int track_decode_buf2(nghttp2_hd_context *context,
uint8_t *buf1, uint8_t *buf2)
{
if(context->buf_tracklen + 2 > context->buf_track_capacity) {
return NGHTTP2_ERR_HEADER_COMP;
}
context->buf_track[context->buf_tracklen++] = buf1;
context->buf_track[context->buf_tracklen++] = buf2;
return 0;
}
static int add_emit_set(nghttp2_hd_context *context, nghttp2_hd_entry *ent)
{
if(context->emit_setlen == context->emit_set_capacity) {
return NGHTTP2_ERR_HEADER_COMP;
}
context->emit_set[context->emit_setlen++] = ent;
++ent->ref;
return 0;
}
static int emit_indexed_header(nghttp2_hd_context *context,
nghttp2_nva_out *nva_out_ptr,
nghttp2_hd_entry *ent)
{
int rv;
/* ent->ref may be 0. This happens if the careless stupid encoder
emits literal block larger than header table capacity with
indexing. */
rv = add_emit_set(context, ent);
if(rv != 0) {
return rv;
}
ent->flags |= NGHTTP2_HD_FLAG_EMIT;
return add_nva(nva_out_ptr,
ent->nv.name, ent->nv.namelen,
ent->nv.value, ent->nv.valuelen);
}
static int emit_newname_header(nghttp2_hd_context *context,
nghttp2_nva_out *nva_out_ptr,
nghttp2_nv *nv,
uint8_t flags)
{
int rv;
rv = add_nva(nva_out_ptr,
nv->name, nv->namelen, nv->value, nv->valuelen);
if(rv != 0) {
return rv;
}
if(flags & NGHTTP2_HD_FLAG_NAME_GIFT) {
if(flags & NGHTTP2_HD_FLAG_VALUE_GIFT) {
return track_decode_buf2(context, nv->name, nv->value);
} else {
return track_decode_buf(context, nv->name);
}
} else if(flags & NGHTTP2_HD_FLAG_VALUE_GIFT) {
return track_decode_buf(context, nv->value);
}
return 0;
}
static int emit_indname_header(nghttp2_hd_context *context,
nghttp2_nva_out *nva_out_ptr,
nghttp2_hd_entry *ent,
uint8_t *value, size_t valuelen,
uint8_t flags)
{
int rv;
rv = add_emit_set(context, ent);
if(rv != 0) {
return rv;
}
rv = add_nva(nva_out_ptr, ent->nv.name, ent->nv.namelen, value, valuelen);
if(rv != 0) {
return rv;
}
if(NGHTTP2_HD_FLAG_VALUE_GIFT) {
return track_decode_buf(context, value);
}
return 0;
}
static int ensure_write_buffer(uint8_t **buf_ptr, size_t *buflen_ptr,
size_t offset, size_t need)
{
int rv;
/* TODO Remove this limitation when header continuation is
implemented. */
if(need + offset > NGHTTP2_MAX_HTTP_FRAME_LENGTH) {
return NGHTTP2_ERR_HEADER_COMP;
}
rv = nghttp2_reserve_buffer(buf_ptr, buflen_ptr, offset + need);
if(rv != 0) {
return NGHTTP2_ERR_NOMEM;
}
return 0;
}
static size_t count_encoded_length(size_t n, int prefix)
{
size_t k = (1 << prefix) - 1;
size_t len = 0;
if(n >= k) {
n -= k;
++len;
} else {
return 1;
}
do {
++len;
if(n >= 128) {
n >>= 7;
} else {
break;
}
} while(n);
return len;
}
static size_t encode_length(uint8_t *buf, size_t n, int prefix)
{
size_t k = (1 << prefix) - 1;
size_t len = 0;
*buf &= ~k;
if(n >= k) {
*buf++ |= k;
n -= k;
++len;
} else {
*buf++ |= n;
return 1;
}
do {
++len;
if(n >= 128) {
*buf++ = (1 << 7) | (n & 0x7f);
n >>= 7;
} else {
*buf++ = n;
break;
}
} while(n);
return len;
}
/*
* Decodes |prefx| prefixed integer stored from |in|. The |last|
* represents the 1 beyond the last of the valid contiguous memory
* region from |in|. The decoded integer must be strictly less than 1
* << 16.
*
* This function returns the next byte of read byte. This function
* stores the decoded integer in |*res| if it succeeds, or stores -1
* in |*res|, indicating decoding error.
*/
static uint8_t* decode_length(ssize_t *res, uint8_t *in, uint8_t *last,
int prefix)
{
int k = (1 << prefix) - 1, r;
if(in == last) {
*res = -1;
return in;
}
if((*in & k) == k) {
*res = k;
} else {
*res = (*in) & k;
return in + 1;
}
++in;
for(r = 0; in != last; ++in, r += 7) {
*res += (*in & 0x7f) << r;
if(*res >= (1 << 16)) {
*res = -1;
return in + 1;
}
if((*in & (1 << 7)) == 0) {
break;
}
}
if(in == last || *in & (1 << 7)) {
*res = -1;
return NULL;
} else {
return in + 1;
}
}
static int emit_indexed_block(uint8_t **buf_ptr, size_t *buflen_ptr,
size_t *offset_ptr, size_t index)
{
int rv;
uint8_t *bufp;
size_t blocklen = count_encoded_length(index, 7);
rv = ensure_write_buffer(buf_ptr, buflen_ptr, *offset_ptr, blocklen);
if(rv != 0) {
return rv;
}
bufp = *buf_ptr + *offset_ptr;
*bufp = 0x80u;
encode_length(bufp, index, 7);
*offset_ptr += blocklen;
return 0;
}
static size_t emit_string(uint8_t *buf, size_t buflen,
size_t enclen, int huffman,
const uint8_t *str, size_t len,
nghttp2_hd_side side)
{
size_t rv;
*buf = huffman ? 1 << 7 : 0;
rv = encode_length(buf, enclen, 7);
buf += rv;
if(huffman) {
nghttp2_hd_huff_encode(buf, buflen - rv, str, len, side);
} else {
assert(enclen == len);
memcpy(buf, str, len);
}
return rv + enclen;
}
static int emit_indname_block(uint8_t **buf_ptr, size_t *buflen_ptr,
size_t *offset_ptr, size_t index,
const uint8_t *value, size_t valuelen,
int inc_indexing,
nghttp2_hd_side side)
{
int rv;
uint8_t *bufp;
size_t encvallen = nghttp2_hd_huff_encode_count(value, valuelen, side);
size_t blocklen = count_encoded_length(index + 1, 6);
int huffman = encvallen < valuelen;
if(!huffman) {
encvallen = valuelen;
}
blocklen += count_encoded_length(encvallen, 7) + encvallen;
rv = ensure_write_buffer(buf_ptr, buflen_ptr, *offset_ptr, blocklen);
if(rv != 0) {
return rv;
}
bufp = *buf_ptr + *offset_ptr;
*bufp = inc_indexing ? 0 : 0x40u;
bufp += encode_length(bufp, index + 1, 6);
bufp += emit_string(bufp, *buflen_ptr - (bufp - *buf_ptr),
encvallen, huffman, value, valuelen, side);
assert(bufp - (*buf_ptr + *offset_ptr) == (ssize_t)blocklen);
*offset_ptr += blocklen;
return 0;
}
static int emit_newname_block(uint8_t **buf_ptr, size_t *buflen_ptr,
size_t *offset_ptr, nghttp2_nv *nv,
int inc_indexing,
nghttp2_hd_side side)
{
int rv;
uint8_t *bufp;
size_t encnamelen =
nghttp2_hd_huff_encode_count(nv->name, nv->namelen, side);
size_t encvallen =
nghttp2_hd_huff_encode_count(nv->value, nv->valuelen, side);
size_t blocklen = 1;
int name_huffman = encnamelen < nv->namelen;
int value_huffman = encvallen < nv->valuelen;
if(!name_huffman) {
encnamelen = nv->namelen;
}
if(!value_huffman) {
encvallen = nv->valuelen;
}
blocklen += count_encoded_length(encnamelen, 7) + encnamelen +
count_encoded_length(encvallen, 7) + encvallen;
rv = ensure_write_buffer(buf_ptr, buflen_ptr, *offset_ptr, blocklen);
if(rv != 0) {
return rv;
}
bufp = *buf_ptr + *offset_ptr;
*bufp++ = inc_indexing ? 0 : 0x40u;
bufp += emit_string(bufp, *buflen_ptr - (bufp - *buf_ptr),
encnamelen, name_huffman, nv->name, nv->namelen, side);
bufp += emit_string(bufp, *buflen_ptr - (bufp - *buf_ptr),
encvallen, value_huffman, nv->value, nv->valuelen, side);
*offset_ptr += blocklen;
return 0;
}
/*
* Emit common header with |index| by toggle off and on (thus 2
* indexed representation emissions).
*/
static int emit_implicit(uint8_t **buf_ptr,
size_t *buflen_ptr,
size_t *offset_ptr,
size_t index)
{
int i;
int rv;
for(i = 0; i < 2; ++i) {
rv = emit_indexed_block(buf_ptr, buflen_ptr, offset_ptr, index);
if(rv != 0) {
return rv;
}
}
return 0;
}
static nghttp2_hd_entry* add_hd_table_incremental(nghttp2_hd_context *context,
uint8_t **buf_ptr,
size_t *buflen_ptr,
size_t *offset_ptr,
nghttp2_nv *nv,
uint8_t entry_flags)
{
int rv;
nghttp2_hd_entry *new_ent;
size_t room = entry_room(nv->namelen, nv->valuelen);
while(context->hd_table_bufsize + room > context->hd_table_bufsize_max &&
context->hd_table.len > 0) {
size_t index = context->hd_table.len - 1;
nghttp2_hd_entry* ent = nghttp2_hd_ringbuf_get(&context->hd_table, index);
context->hd_table_bufsize -= entry_room(ent->nv.namelen, ent->nv.valuelen);
if(context->role == NGHTTP2_HD_ROLE_DEFLATE) {
if(context->hd_table_bufsize < context->local_hd_table_bufsize) {
context->local_hd_table_bufsize -= entry_room(ent->nv.namelen,
ent->nv.valuelen);
--context->local_hd_tablelen;
}
if(ent->flags & NGHTTP2_HD_FLAG_IMPLICIT_EMIT) {
/* Emit common header just before it slips away from the
table. If we don't do this, we have to emit it in literal
representation which hurts compression. */
rv = emit_implicit(buf_ptr, buflen_ptr, offset_ptr, index);
if(rv != 0) {
return NULL;
}
}
}
nghttp2_hd_ringbuf_pop_back(&context->hd_table);
if(--ent->ref == 0) {
nghttp2_hd_entry_free(ent);
free(ent);
}
}
if(context->role == NGHTTP2_HD_ROLE_DEFLATE) {
while(context->local_hd_table_bufsize + room >
context->local_hd_table_bufsize_max
&& context->local_hd_tablelen > 0) {
size_t index = context->local_hd_tablelen - 1;
nghttp2_hd_entry *ent =
nghttp2_hd_ringbuf_get(&context->hd_table, index);
context->local_hd_table_bufsize -= entry_room(ent->nv.namelen,
ent->nv.valuelen);
--context->local_hd_tablelen;
if(ent->flags & NGHTTP2_HD_FLAG_IMPLICIT_EMIT) {
/* Just like a normal eviction, implicit header must be
emitted twice. */
rv = emit_implicit(buf_ptr, buflen_ptr, offset_ptr, index);
if(rv != 0) {
return NULL;
}
ent->flags ^= NGHTTP2_HD_FLAG_IMPLICIT_EMIT;
}
if(ent->flags & NGHTTP2_HD_FLAG_REFSET) {
/* We need to drop entry from reference set. */
rv = emit_indexed_block(buf_ptr, buflen_ptr, offset_ptr, index);
if(rv != 0) {
return NULL;
}
ent->flags ^= NGHTTP2_HD_FLAG_REFSET;
}
/* Release memory. We don't remove entry from the header table
at this moment. */
if(ent->flags & NGHTTP2_HD_FLAG_NAME_ALLOC) {
free(ent->nv.name);
ent->nv.name = NULL;
ent->flags ^= NGHTTP2_HD_FLAG_NAME_ALLOC;
}
if(ent->flags & NGHTTP2_HD_FLAG_VALUE_ALLOC) {
free(ent->nv.value);
ent->nv.value = NULL;
ent->flags ^= NGHTTP2_HD_FLAG_VALUE_ALLOC;
}
}
}
new_ent = malloc(sizeof(nghttp2_hd_entry));
if(new_ent == NULL) {
return NULL;
}
if(context->role == NGHTTP2_HD_ROLE_DEFLATE &&
room > context->local_hd_table_bufsize_max) {
uint8_t flags = entry_flags &
~(NGHTTP2_HD_FLAG_NAME_ALLOC | NGHTTP2_HD_FLAG_VALUE_ALLOC |
NGHTTP2_HD_FLAG_NAME_GIFT | NGHTTP2_HD_FLAG_VALUE_GIFT);
rv = nghttp2_hd_entry_init(new_ent, flags,
NULL, nv->namelen, NULL, nv->valuelen);
if(rv != 0) {
free(new_ent);
return NULL;
}
if(flags & NGHTTP2_HD_FLAG_NAME_GIFT) {
free(nv->name);
nv->name = NULL;
}
if(flags & NGHTTP2_HD_FLAG_VALUE_GIFT) {
free(nv->value);
nv->value = NULL;
}
/* caller must emit indexed repr to toggle off new_ent from
reference set. We cannot do it here because it may break the
indexing. */
} else {
rv = nghttp2_hd_entry_init(new_ent,
entry_flags,
nv->name, nv->namelen, nv->value, nv->valuelen);
if(rv != 0) {
free(new_ent);
return NULL;
}
}
if(room > context->hd_table_bufsize_max) {
/* The entry taking more than NGHTTP2_HD_MAX_BUFFER_SIZE is
immediately evicted. */
--new_ent->ref;
} else {
context->hd_table_bufsize += room;
new_ent->flags |= NGHTTP2_HD_FLAG_REFSET;
nghttp2_hd_ringbuf_push_front(&context->hd_table, new_ent);
if(context->role == NGHTTP2_HD_ROLE_DEFLATE &&
room <= context->local_hd_table_bufsize_max) {
context->local_hd_table_bufsize += room;
++context->local_hd_tablelen;
}
}
return new_ent;
}
static ssize_t find_in_hd_table(nghttp2_hd_context *context, nghttp2_nv *nv)
{
size_t i;
size_t max = context->role == NGHTTP2_HD_ROLE_DEFLATE ?
context->local_hd_tablelen : context->hd_table.len;
for(i = 0; i < max; ++i) {
nghttp2_hd_entry *ent = nghttp2_hd_ringbuf_get(&context->hd_table, i);
if(nghttp2_nv_equal(&ent->nv, nv)) {
return i;
}
}
for(i = 0; i < STATIC_TABLE_LENGTH; ++i) {
nghttp2_hd_entry *ent = &static_table[i];
if(nghttp2_nv_equal(&ent->nv, nv)) {
return context->hd_table.len + i;
}
}
return -1;
}
static ssize_t find_name_in_hd_table(nghttp2_hd_context *context,
nghttp2_nv *nv)
{
size_t i;
size_t max = context->role == NGHTTP2_HD_ROLE_DEFLATE ?
context->local_hd_tablelen : context->hd_table.len;
for(i = 0; i < max; ++i) {
nghttp2_hd_entry *ent = nghttp2_hd_ringbuf_get(&context->hd_table, i);
if(ent->nv.namelen == nv->namelen &&
memcmp(ent->nv.name, nv->name, nv->namelen) == 0) {
return i;
}
}
for(i = 0; i < STATIC_TABLE_LENGTH; ++i) {
nghttp2_hd_entry *ent = &static_table[i];
if(ent->nv.namelen == nv->namelen &&
memcmp(ent->nv.name, nv->name, nv->namelen) == 0) {
return context->hd_table.len + i;
}
}
return -1;
}
int nghttp2_hd_change_table_size(nghttp2_hd_context *context,
size_t hd_table_bufsize_max)
{
int rv;
rv = nghttp2_hd_ringbuf_reserve
(&context->hd_table, hd_table_bufsize_max / NGHTTP2_HD_ENTRY_OVERHEAD);
if(rv != 0) {
return rv;
}
context->hd_table_bufsize_max = hd_table_bufsize_max;
while(context->hd_table_bufsize > context->hd_table_bufsize_max &&
context->hd_table.len > 0) {
size_t index = context->hd_table.len - 1;
nghttp2_hd_entry* ent = nghttp2_hd_ringbuf_get(&context->hd_table, index);
context->hd_table_bufsize -= entry_room(ent->nv.namelen, ent->nv.valuelen);
if(context->role == NGHTTP2_HD_ROLE_DEFLATE) {
if(context->hd_table_bufsize < context->local_hd_table_bufsize) {
context->local_hd_table_bufsize -= entry_room(ent->nv.namelen,
ent->nv.valuelen);
--context->local_hd_tablelen;
}
}
nghttp2_hd_ringbuf_pop_back(&context->hd_table);
if(--ent->ref == 0) {
nghttp2_hd_entry_free(ent);
free(ent);
}
}
return 0;
}
static int check_index_range(nghttp2_hd_context *context, size_t index)
{
return index < context->hd_table.len + STATIC_TABLE_LENGTH;
}
nghttp2_hd_entry* nghttp2_hd_table_get(nghttp2_hd_context *context,
size_t index)
{
assert(check_index_range(context, index));
if(index < context->hd_table.len) {
return nghttp2_hd_ringbuf_get(&context->hd_table, index);
} else {
return &static_table[index - context->hd_table.len];
}
}
static int deflate_nv(nghttp2_hd_context *deflater,
uint8_t **buf_ptr, size_t *buflen_ptr,
size_t *offset_ptr,
nghttp2_nv *nv)
{
int rv;
nghttp2_hd_entry *ent;
rv = find_in_hd_table(deflater, nv);
if(rv != -1) {
size_t index = rv;
ent = nghttp2_hd_table_get(deflater, index);
if(index >= deflater->hd_table.len) {
nghttp2_hd_entry *new_ent;
/* It is important to first add entry to the header table and
let eviction go. If NGHTTP2_HD_FLAG_IMPLICIT_EMIT entry is
evicted, it must be emitted before the |nv|. */
new_ent = add_hd_table_incremental(deflater, buf_ptr, buflen_ptr,
offset_ptr, &ent->nv,
NGHTTP2_HD_FLAG_NONE);
if(!new_ent) {
return NGHTTP2_ERR_HEADER_COMP;
}
if(new_ent->ref == 0) {
nghttp2_hd_entry_free(new_ent);
free(new_ent);
new_ent = NULL;
} else if(new_ent->nv.name != NULL) {
/* new_ent->ref > 0 and nv.name is not NULL means that new_ent is
in the reference set and in local_hd_table_bufsize */
new_ent->flags |= NGHTTP2_HD_FLAG_EMIT;
}
rv = emit_indexed_block(buf_ptr, buflen_ptr, offset_ptr, index);
if(rv != 0) {
return rv;
}
} else if((ent->flags & NGHTTP2_HD_FLAG_REFSET) == 0) {
ent->flags |= NGHTTP2_HD_FLAG_REFSET | NGHTTP2_HD_FLAG_EMIT;
rv = emit_indexed_block(buf_ptr, buflen_ptr, offset_ptr, index);
if(rv != 0) {
return rv;
}
} else {
int num_emits = 0;
if(ent->flags & NGHTTP2_HD_FLAG_EMIT) {
/* occurrences of the same indexed representation. Emit index
twice. */
num_emits = 2;
} else if(ent->flags & NGHTTP2_HD_FLAG_IMPLICIT_EMIT) {
/* ent was implicitly emitted because it is the common
header field. To support occurrences of the same indexed
representation, we have to emit 4 times. This is because
"implicitly emitted" means actually not emitted at
all. So first 2 emits performs 1st header appears in the
reference set. And another 2 emits are done for 2nd
(current) header. */
ent->flags ^= NGHTTP2_HD_FLAG_IMPLICIT_EMIT;
ent->flags |= NGHTTP2_HD_FLAG_EMIT;
num_emits = 4;
} else {
/* This is common header and not emitted in the current
run. Just mark IMPLICIT_EMIT, in the hope that we are not
required to emit anything for this. We will emit toggle
off/on for this entry if it is removed from the header
table. */
ent->flags |= NGHTTP2_HD_FLAG_IMPLICIT_EMIT;
}
for(; num_emits > 0; --num_emits) {
rv = emit_indexed_block(buf_ptr, buflen_ptr, offset_ptr, index);
if(rv != 0) {
break;
}
}
}
} else {
ssize_t index = -1;
int incidx = 0;
rv = find_name_in_hd_table(deflater, nv);
if(rv != -1) {
index = rv;
}
if(entry_room(nv->namelen, nv->valuelen) <= NGHTTP2_HD_MAX_ENTRY_SIZE) {
nghttp2_hd_entry *new_ent;
if(index >= (ssize_t)deflater->hd_table.len) {
nghttp2_nv nv_indname;
nv_indname = *nv;
nv_indname.name = nghttp2_hd_table_get(deflater, index)->nv.name;
new_ent = add_hd_table_incremental(deflater, buf_ptr, buflen_ptr,
offset_ptr, &nv_indname,
NGHTTP2_HD_FLAG_VALUE_ALLOC);
} else {
new_ent = add_hd_table_incremental(deflater, buf_ptr, buflen_ptr,
offset_ptr, nv,
NGHTTP2_HD_FLAG_NAME_ALLOC |
NGHTTP2_HD_FLAG_VALUE_ALLOC);
}
if(!new_ent) {
return NGHTTP2_ERR_HEADER_COMP;
}
if(new_ent->ref == 0) {
nghttp2_hd_entry_free(new_ent);
free(new_ent);
} else if(new_ent->nv.name != NULL) {
/* new_ent->ref > 0 and nv.name is not NULL means that new_ent is
in the reference set and in local_hd_table_bufsize */
new_ent->flags |= NGHTTP2_HD_FLAG_EMIT;
}
incidx = 1;
}
if(index == -1) {
rv = emit_newname_block(buf_ptr, buflen_ptr, offset_ptr, nv, incidx,
deflater->side);
} else {
rv = emit_indname_block(buf_ptr, buflen_ptr, offset_ptr, index,
nv->value, nv->valuelen, incidx,
deflater->side);
}
if(rv != 0) {
return rv;
}
}
return 0;
}
static int deflate_post_process_hd_entry(nghttp2_hd_entry *ent,
size_t index,
uint8_t **buf_ptr,
size_t *buflen_ptr,
size_t *offset_ptr)
{
int rv;
if((ent->flags & NGHTTP2_HD_FLAG_REFSET) &&
(ent->flags & NGHTTP2_HD_FLAG_IMPLICIT_EMIT) == 0 &&
(ent->flags & NGHTTP2_HD_FLAG_EMIT) == 0) {
/* This entry is not present in the current header set and must
be removed. */
ent->flags ^= NGHTTP2_HD_FLAG_REFSET;
rv = emit_indexed_block(buf_ptr, buflen_ptr, offset_ptr, index);
if(rv != 0) {
return rv;
}
}
ent->flags &= ~(NGHTTP2_HD_FLAG_EMIT | NGHTTP2_HD_FLAG_IMPLICIT_EMIT);
return 0;
}
ssize_t nghttp2_hd_deflate_hd(nghttp2_hd_context *deflater,
uint8_t **buf_ptr, size_t *buflen_ptr,
size_t nv_offset,
nghttp2_nv *nv, size_t nvlen)
{
size_t i, offset;
int rv = 0;
if(deflater->bad) {
return NGHTTP2_ERR_HEADER_COMP;
}
offset = nv_offset;
for(i = 0; i < nvlen; ++i) {
rv = deflate_nv(deflater, buf_ptr, buflen_ptr, &offset, &nv[i]);
if(rv != 0) {
goto fail;
}
}
for(i = 0; i < deflater->hd_table.len; ++i) {
nghttp2_hd_entry *ent = nghttp2_hd_ringbuf_get(&deflater->hd_table, i);
rv = deflate_post_process_hd_entry(ent, i, buf_ptr, buflen_ptr, &offset);
if(rv != 0) {
goto fail;
}
}
return offset - nv_offset;
fail:
deflater->bad = 1;
return rv;
}
static int inflater_post_process_hd_entry(nghttp2_hd_context *inflater,
nghttp2_hd_entry *ent,
nghttp2_nva_out *nva_out_ptr)
{
int rv;
if((ent->flags & NGHTTP2_HD_FLAG_REFSET) &&
(ent->flags & NGHTTP2_HD_FLAG_EMIT) == 0) {
rv = emit_indexed_header(inflater, nva_out_ptr, ent);
if(rv != 0) {
return rv;
}
}
ent->flags &= ~NGHTTP2_HD_FLAG_EMIT;
return 0;
}
static ssize_t inflate_decode(uint8_t **dest_ptr, uint8_t *in, size_t inlen,
nghttp2_hd_side side)
{
ssize_t declen = nghttp2_hd_huff_decode_count(in, inlen, side);
if(declen == -1) {
return NGHTTP2_ERR_HEADER_COMP;
}
*dest_ptr = malloc(declen);
if(*dest_ptr == NULL) {
return NGHTTP2_ERR_HEADER_COMP;
}
nghttp2_hd_huff_decode(*dest_ptr, declen, in, inlen, side);
return declen;
}
ssize_t nghttp2_hd_inflate_hd(nghttp2_hd_context *inflater,
nghttp2_nv **nva_ptr,
uint8_t *in, size_t inlen)
{
size_t i;
int rv = 0;
uint8_t *last = in + inlen;
nghttp2_nva_out nva_out;
memset(&nva_out, 0, sizeof(nva_out));
if(inflater->bad) {
return NGHTTP2_ERR_HEADER_COMP;
}
*nva_ptr = NULL;
for(; in != last;) {
uint8_t c = *in;
if(c & 0x80u) {
/* Indexed Header Repr */
ssize_t index;
nghttp2_hd_entry *ent;
in = decode_length(&index, in, last, 7);
if(index < 0) {
rv = NGHTTP2_ERR_HEADER_COMP;
goto fail;
}
if(!check_index_range(inflater, index)) {
rv = NGHTTP2_ERR_HEADER_COMP;
goto fail;
}
ent = nghttp2_hd_table_get(inflater, index);
if(index >= (ssize_t)inflater->hd_table.len) {
nghttp2_hd_entry *new_ent;
new_ent = add_hd_table_incremental(inflater, NULL, NULL, NULL,
&ent->nv, NGHTTP2_HD_FLAG_NONE);
if(!new_ent) {
rv = NGHTTP2_ERR_HEADER_COMP;
goto fail;
}
/* new_ent->ref == 0 may be hold but emit_indexed_header
tracks new_ent, so there is no leak. */
rv = emit_indexed_header(inflater, &nva_out, new_ent);
} else {
ent->flags ^= NGHTTP2_HD_FLAG_REFSET;
if(ent->flags & NGHTTP2_HD_FLAG_REFSET) {
rv = emit_indexed_header(inflater, &nva_out, ent);
}
}
if(rv != 0) {
goto fail;
}
} else if(c == 0x40u || c == 0) {
/* Literal Header Repr - New Name */
nghttp2_nv nv;
ssize_t namelen, valuelen;
int name_huffman, value_huffman;
uint8_t *decoded_huffman_name = NULL, *decoded_huffman_value = NULL;
if(++in == last) {
rv = NGHTTP2_ERR_HEADER_COMP;
goto fail;
}
name_huffman = *in & (1 << 7);
in = decode_length(&namelen, in, last, 7);
if(namelen < 0 || in + namelen > last) {
rv = NGHTTP2_ERR_HEADER_COMP;
goto fail;
}
if(name_huffman) {
rv = inflate_decode(&nv.name, in, namelen, inflater->side);
if(rv < 0) {
goto fail;
}
decoded_huffman_name = nv.name;
nv.namelen = rv;
} else {
nv.name = in;
nv.namelen = namelen;
}
in += namelen;
if(!nghttp2_check_header_name(nv.name, nv.namelen)) {
free(decoded_huffman_name);
rv = NGHTTP2_ERR_HEADER_COMP;
goto fail;
}
if(in == last) {
free(decoded_huffman_name);
rv = NGHTTP2_ERR_HEADER_COMP;
goto fail;
}
value_huffman = *in & (1 << 7);
in = decode_length(&valuelen, in, last, 7);
if(valuelen < 0 || in + valuelen > last) {
free(decoded_huffman_name);
rv = NGHTTP2_ERR_HEADER_COMP;
goto fail;
}
if(value_huffman) {
rv = inflate_decode(&nv.value, in, valuelen, inflater->side);
if(rv < 0) {
free(decoded_huffman_name);
goto fail;
}
decoded_huffman_value = nv.value;
nv.valuelen = rv;
} else {
nv.value = in;
nv.valuelen = valuelen;
}
in += valuelen;
nghttp2_downcase(nv.name, nv.namelen);
if(c == 0x40u) {
int flags = NGHTTP2_HD_FLAG_NONE;
if(name_huffman) {
flags |= NGHTTP2_HD_FLAG_NAME_GIFT;
}
if(value_huffman) {
flags |= NGHTTP2_HD_FLAG_VALUE_GIFT;
}
rv = emit_newname_header(inflater, &nva_out, &nv, flags);
if(rv != 0) {
free(decoded_huffman_name);
free(decoded_huffman_value);
}
} else {
nghttp2_hd_entry *new_ent;
uint8_t ent_flags = NGHTTP2_HD_FLAG_NAME_ALLOC |
NGHTTP2_HD_FLAG_VALUE_ALLOC;
if(name_huffman) {
ent_flags |= NGHTTP2_HD_FLAG_NAME_GIFT;
}
if(value_huffman) {
ent_flags |= NGHTTP2_HD_FLAG_VALUE_GIFT;
}
new_ent = add_hd_table_incremental(inflater, NULL, NULL, NULL, &nv,
ent_flags);
if(new_ent) {
rv = emit_indexed_header(inflater, &nva_out, new_ent);
} else {
free(decoded_huffman_name);
free(decoded_huffman_value);
rv = NGHTTP2_ERR_HEADER_COMP;
}
}
if(rv != 0) {
goto fail;
}
} else {
/* Literal Header Repr - Indexed Name */
nghttp2_hd_entry *ent;
uint8_t *value;
ssize_t valuelen, index;
int value_huffman;
uint8_t *decoded_huffman_value = NULL;
in = decode_length(&index, in, last, 6);
if(index < 0) {
rv = NGHTTP2_ERR_HEADER_COMP;
goto fail;
}
--index;
if(!check_index_range(inflater, index)) {
rv = NGHTTP2_ERR_HEADER_COMP;
goto fail;
}
ent = nghttp2_hd_table_get(inflater, index);
if(in == last) {
rv = NGHTTP2_ERR_HEADER_COMP;
goto fail;
}
value_huffman = *in & (1 << 7);
in = decode_length(&valuelen, in , last, 7);
if(valuelen < 0 || in + valuelen > last) {
rv = NGHTTP2_ERR_HEADER_COMP;
goto fail;
}
if(value_huffman) {
rv = inflate_decode(&value, in, valuelen, inflater->side);
if(rv < 0) {
goto fail;
}
decoded_huffman_value = value;
in += valuelen;
valuelen = rv;
} else {
value = in;
in += valuelen;
}
if((c & 0x40u) == 0x40u) {
uint8_t flags = NGHTTP2_HD_FLAG_NONE;
if(value_huffman) {
flags = NGHTTP2_HD_FLAG_VALUE_GIFT;
}
rv = emit_indname_header(inflater, &nva_out, ent, value, valuelen,
flags);
if(rv != 0) {
free(decoded_huffman_value);
}
} else {
nghttp2_nv nv;
nghttp2_hd_entry *new_ent;
uint8_t ent_flags = NGHTTP2_HD_FLAG_VALUE_ALLOC;
if(value_huffman) {
ent_flags |= NGHTTP2_HD_FLAG_VALUE_GIFT;
}
++ent->ref;
nv.name = ent->nv.name;
if((size_t)index < inflater->hd_table.len) {
ent_flags |= NGHTTP2_HD_FLAG_NAME_ALLOC;
}
nv.namelen = ent->nv.namelen;
nv.value = value;
nv.valuelen = valuelen;
new_ent = add_hd_table_incremental(inflater, NULL, NULL, NULL, &nv,
ent_flags);
if(--ent->ref == 0) {
nghttp2_hd_entry_free(ent);
free(ent);
}
if(new_ent) {
rv = emit_indexed_header(inflater, &nva_out, new_ent);
} else {
free(decoded_huffman_value);
rv = NGHTTP2_ERR_HEADER_COMP;
}
}
if(rv != 0) {
goto fail;
}
}
}
for(i = 0; i < inflater->hd_table.len; ++i) {
nghttp2_hd_entry *ent = nghttp2_hd_ringbuf_get(&inflater->hd_table, i);
rv = inflater_post_process_hd_entry(inflater, ent, &nva_out);
if(rv != 0) {
goto fail;
}
}
nghttp2_nv_array_sort(nva_out.nva, nva_out.nvlen);
*nva_ptr = nva_out.nva;
return nva_out.nvlen;
fail:
inflater->bad = 1;
free(nva_out.nva);
return rv;
}
int nghttp2_hd_end_headers(nghttp2_hd_context *context)
{
size_t i;
for(i = 0; i < context->emit_setlen; ++i) {
nghttp2_hd_entry *ent = context->emit_set[i];
if(--ent->ref == 0) {
nghttp2_hd_entry_free(ent);
free(ent);
}
}
context->emit_setlen = 0;
for(i = 0; i < context->buf_tracklen; ++i) {
free(context->buf_track[i]);
}
context->buf_tracklen = 0;
return 0;
}
int nghttp2_hd_emit_indname_block(uint8_t **buf_ptr, size_t *buflen_ptr,
size_t *offset_ptr, size_t index,
const uint8_t *value, size_t valuelen,
int inc_indexing,
nghttp2_hd_side side)
{
return emit_indname_block(buf_ptr, buflen_ptr, offset_ptr,
index, value, valuelen, inc_indexing,
side);
}
int nghttp2_hd_emit_newname_block(uint8_t **buf_ptr, size_t *buflen_ptr,
size_t *offset_ptr, nghttp2_nv *nv,
int inc_indexing,
nghttp2_hd_side side)
{
return emit_newname_block(buf_ptr, buflen_ptr, offset_ptr, nv, inc_indexing,
side);
}