blob: ddcdce614f6184900cea1f566e23afc68d75315d [file] [log] [blame]
/*
* Stream filters related variables and functions.
*
* Copyright (C) 2015 Qualys Inc., Christopher Faulet <cfaulet@qualys.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
*/
#include <common/buffer.h>
#include <common/cfgparse.h>
#include <common/htx.h>
#include <common/initcall.h>
#include <common/mini-clist.h>
#include <common/standard.h>
#include <types/compression.h>
#include <types/filters.h>
#include <types/proxy.h>
#include <types/sample.h>
#include <proto/compression.h>
#include <proto/filters.h>
#include <proto/hdr_idx.h>
#include <proto/http_htx.h>
#include <proto/proto_http.h>
#include <proto/sample.h>
#include <proto/stream.h>
const char *http_comp_flt_id = "compression filter";
struct flt_ops comp_ops;
struct comp_state {
struct comp_ctx *comp_ctx; /* compression context */
struct comp_algo *comp_algo; /* compression algorithm if not NULL */
/* Following fields are used by the legacy code only: */
int hdrs_len;
int tlrs_len;
int consumed;
int initialized;
int finished;
};
/* Pools used to allocate comp_state structs */
DECLARE_STATIC_POOL(pool_head_comp_state, "comp_state", sizeof(struct comp_state));
static THREAD_LOCAL struct buffer tmpbuf;
static THREAD_LOCAL struct buffer zbuf;
static int select_compression_request_header(struct comp_state *st,
struct stream *s,
struct http_msg *msg);
static int select_compression_response_header(struct comp_state *st,
struct stream *s,
struct http_msg *msg);
static int set_compression_response_header(struct comp_state *st,
struct stream *s,
struct http_msg *msg);
static int htx_compression_buffer_init(struct htx *htx, struct buffer *out);
static int htx_compression_buffer_add_data(struct comp_state *st, const char *data, size_t len,
struct buffer *out);
static int htx_compression_buffer_end(struct comp_state *st, struct buffer *out, int end);
static int http_compression_buffer_init(struct channel *inc, struct buffer *out);
static int http_compression_buffer_add_data(struct comp_state *st,
struct buffer *in,
int in_out,
struct buffer *out, int sz);
static int http_compression_buffer_end(struct comp_state *st, struct stream *s,
struct channel *chn, struct buffer *out,
int end);
/***********************************************************************/
static int
comp_flt_init(struct proxy *px, struct flt_conf *fconf)
{
fconf->flags |= FLT_CFG_FL_HTX;
return 0;
}
static int
comp_flt_init_per_thread(struct proxy *px, struct flt_conf *fconf)
{
if (!tmpbuf.size && b_alloc(&tmpbuf) == NULL)
return -1;
if (!zbuf.size && b_alloc(&zbuf) == NULL)
return -1;
return 0;
}
static void
comp_flt_deinit_per_thread(struct proxy *px, struct flt_conf *fconf)
{
if (tmpbuf.size)
b_free(&tmpbuf);
if (zbuf.size)
b_free(&zbuf);
}
static int
comp_start_analyze(struct stream *s, struct filter *filter, struct channel *chn)
{
if (filter->ctx == NULL) {
struct comp_state *st;
st = pool_alloc_dirty(pool_head_comp_state);
if (st == NULL)
return -1;
st->comp_algo = NULL;
st->comp_ctx = NULL;
st->hdrs_len = 0;
st->tlrs_len = 0;
st->consumed = 0;
st->initialized = 0;
st->finished = 0;
filter->ctx = st;
/* Register post-analyzer on AN_RES_WAIT_HTTP because we need to
* analyze response headers before http-response rules execution
* to be sure we can use res.comp and res.comp_algo sample
* fetches */
filter->post_analyzers |= AN_RES_WAIT_HTTP;
}
return 1;
}
static int
comp_end_analyze(struct stream *s, struct filter *filter, struct channel *chn)
{
struct comp_state *st = filter->ctx;
if (!st)
goto end;
/* release any possible compression context */
if (st->comp_algo)
st->comp_algo->end(&st->comp_ctx);
pool_free(pool_head_comp_state, st);
filter->ctx = NULL;
end:
return 1;
}
static int
comp_http_headers(struct stream *s, struct filter *filter, struct http_msg *msg)
{
struct comp_state *st = filter->ctx;
if (!strm_fe(s)->comp && !s->be->comp)
goto end;
if (!(msg->chn->flags & CF_ISRESP))
select_compression_request_header(st, s, msg);
else {
/* Response headers have already been checked in
* comp_http_post_analyze callback. */
if (st->comp_algo) {
if (!set_compression_response_header(st, s, msg))
goto end;
register_data_filter(s, msg->chn, filter);
if (!IS_HTX_STRM(s))
st->hdrs_len = s->txn->rsp.sov;
}
}
end:
return 1;
}
static int
comp_http_post_analyze(struct stream *s, struct filter *filter,
struct channel *chn, unsigned an_bit)
{
struct http_txn *txn = s->txn;
struct http_msg *msg = &txn->rsp;
struct comp_state *st = filter->ctx;
if (an_bit != AN_RES_WAIT_HTTP)
goto end;
if (!strm_fe(s)->comp && !s->be->comp)
goto end;
select_compression_response_header(st, s, msg);
end:
return 1;
}
static int
comp_http_payload(struct stream *s, struct filter *filter, struct http_msg *msg,
unsigned int offset, unsigned int len)
{
struct comp_state *st = filter->ctx;
struct htx *htx = htxbuf(&msg->chn->buf);
struct htx_blk *blk;
struct htx_ret htx_ret;
int ret, consumed = 0, to_forward = 0;
htx_ret = htx_find_blk(htx, offset);
blk = htx_ret.blk;
offset = htx_ret.ret;
while (blk && len) {
enum htx_blk_type type = htx_get_blk_type(blk);
uint32_t sz = htx_get_blksz(blk);
struct ist v;
switch (type) {
case HTX_BLK_UNUSED:
break;
case HTX_BLK_DATA:
v = htx_get_blk_value(htx, blk);
v.ptr += offset;
v.len -= offset;
if (v.len > len)
v.len = len;
if (htx_compression_buffer_init(htx, &trash) < 0) {
msg->chn->flags |= CF_WAKE_WRITE;
goto end;
}
ret = htx_compression_buffer_add_data(st, v.ptr, v.len, &trash);
if (ret < 0)
goto error;
if (htx_compression_buffer_end(st, &trash, 0) < 0)
goto error;
len -= ret;
consumed += ret;
to_forward += b_data(&trash);
if (ret == sz && !b_data(&trash)) {
offset = 0;
blk = htx_remove_blk(htx, blk);
continue;
}
v.len = ret;
blk = htx_replace_blk_value(htx, blk, v, ist2(b_head(&trash), b_data(&trash)));
break;
case HTX_BLK_EOD:
case HTX_BLK_TLR:
case HTX_BLK_EOM:
if (msg->flags & HTTP_MSGF_COMPRESSING) {
if (htx_compression_buffer_init(htx, &trash) < 0) {
msg->chn->flags |= CF_WAKE_WRITE;
goto end;
}
if (htx_compression_buffer_end(st, &trash, 1) < 0)
goto error;
blk = htx_add_data_before(htx, blk, ist2(b_head(&trash), b_data(&trash)));
if (!blk)
goto error;
to_forward += b_data(&trash);
msg->flags &= ~HTTP_MSGF_COMPRESSING;
/* We let the mux add last empty chunk and empty trailers */
}
/* fall through */
default:
sz -= offset;
if (sz > len)
sz = len;
consumed += sz;
to_forward += sz;
len -= sz;
break;
}
offset = 0;
blk = htx_get_next_blk(htx, blk);
}
end:
if (to_forward != consumed)
flt_update_offsets(filter, msg->chn, to_forward - consumed);
if (st->comp_ctx && st->comp_ctx->cur_lvl > 0) {
update_freq_ctr(&global.comp_bps_out, to_forward);
HA_ATOMIC_ADD(&strm_fe(s)->fe_counters.comp_out, to_forward);
HA_ATOMIC_ADD(&s->be->be_counters.comp_out, to_forward);
}
return to_forward;
error:
return -1;
}
static int
comp_http_data(struct stream *s, struct filter *filter, struct http_msg *msg)
{
struct comp_state *st = filter->ctx;
struct channel *chn = msg->chn;
unsigned int *nxt = &flt_rsp_nxt(filter);
unsigned int len;
int ret;
len = MIN(msg->chunk_len + msg->next, ci_data(chn)) - *nxt;
if (!len)
return len;
if (!st->initialized) {
unsigned int fwd = flt_rsp_fwd(filter) + st->hdrs_len;
b_reset(&tmpbuf);
c_adv(chn, fwd);
ret = http_compression_buffer_init(chn, &zbuf);
c_rew(chn, fwd);
if (ret < 0) {
msg->chn->flags |= CF_WAKE_WRITE;
return 0;
}
}
if (msg->flags & HTTP_MSGF_TE_CHNK) {
int block;
len = MIN(b_room(&tmpbuf), len);
c_adv(chn, *nxt);
block = ci_contig_data(chn);
memcpy(b_tail(&tmpbuf), ci_head(chn), block);
if (len > block)
memcpy(b_tail(&tmpbuf)+block, b_orig(&chn->buf), len-block);
c_rew(chn, *nxt);
b_add(&tmpbuf, len);
ret = len;
}
else {
c_adv(chn, *nxt);
ret = http_compression_buffer_add_data(st, &chn->buf, co_data(chn), &zbuf, len);
c_rew(chn, *nxt);
if (ret < 0)
return ret;
}
st->initialized = 1;
msg->next += ret;
msg->chunk_len -= ret;
*nxt = msg->next;
return 0;
}
static int
comp_http_chunk_trailers(struct stream *s, struct filter *filter,
struct http_msg *msg)
{
struct comp_state *st = filter->ctx;
if (!st->initialized) {
if (!st->finished) {
struct channel *chn = msg->chn;
unsigned int fwd = flt_rsp_fwd(filter) + st->hdrs_len;
b_reset(&tmpbuf);
c_adv(chn, fwd);
http_compression_buffer_init(chn, &zbuf);
c_rew(chn, fwd);
st->initialized = 1;
}
}
st->tlrs_len = msg->sol;
return 1;
}
static int
comp_http_forward_data(struct stream *s, struct filter *filter,
struct http_msg *msg, unsigned int len)
{
struct comp_state *st = filter->ctx;
int ret;
/* To work, previous filters MUST forward all data */
if (flt_rsp_fwd(filter) + len != flt_rsp_nxt(filter)) {
ha_warning("HTTP compression failed: unexpected behavior of previous filters\n");
return -1;
}
if (!st->initialized) {
if (!len) {
/* Nothing to forward */
ret = len;
}
else if (st->hdrs_len > len) {
/* Forward part of headers */
ret = len;
st->hdrs_len -= len;
}
else if (st->hdrs_len > 0) {
/* Forward remaining headers */
ret = st->hdrs_len;
st->hdrs_len = 0;
}
else if (msg->msg_state < HTTP_MSG_TRAILERS) {
/* Do not forward anything for now. This only happens
* with chunk-encoded responses. Waiting data are part
* of the chunk envelope (the chunk size or the chunk
* CRLF). These data will be skipped during the
* compression. */
ret = 0;
}
else {
/* Forward trailers data */
ret = len;
}
return ret;
}
if (msg->flags & HTTP_MSGF_TE_CHNK) {
ret = http_compression_buffer_add_data(st, &tmpbuf, 0,
&zbuf, b_data(&tmpbuf));
if (ret != b_data(&tmpbuf)) {
ha_warning("HTTP compression failed: Must consume %u bytes but only %d bytes consumed\n",
(unsigned int)b_data(&tmpbuf), ret);
return -1;
}
}
st->consumed = len - st->hdrs_len - st->tlrs_len;
c_adv(msg->chn, flt_rsp_fwd(filter) + st->hdrs_len);
ret = http_compression_buffer_end(st, s, msg->chn, &zbuf, msg->msg_state >= HTTP_MSG_TRAILERS);
c_rew(msg->chn, flt_rsp_fwd(filter) + st->hdrs_len);
if (ret < 0)
return ret;
flt_change_forward_size(filter, msg->chn, ret - st->consumed);
msg->next += (ret - st->consumed);
ret += st->hdrs_len + st->tlrs_len;
st->initialized = 0;
st->finished = (msg->msg_state >= HTTP_MSG_TRAILERS);
st->hdrs_len = 0;
st->tlrs_len = 0;
return ret;
}
static int
comp_http_end(struct stream *s, struct filter *filter,
struct http_msg *msg)
{
struct comp_state *st = filter->ctx;
if (!(msg->chn->flags & CF_ISRESP) || !st || !st->comp_algo)
goto end;
if (strm_fe(s)->mode == PR_MODE_HTTP)
HA_ATOMIC_ADD(&strm_fe(s)->fe_counters.p.http.comp_rsp, 1);
if ((s->flags & SF_BE_ASSIGNED) && (s->be->mode == PR_MODE_HTTP))
HA_ATOMIC_ADD(&s->be->be_counters.p.http.comp_rsp, 1);
end:
return 1;
}
/***********************************************************************/
static int
http_set_comp_reshdr(struct comp_state *st, struct stream *s, struct http_msg *msg)
{
struct http_txn *txn = s->txn;
/*
* Add Content-Encoding header when it's not identity encoding.
* RFC 2616 : Identity encoding: This content-coding is used only in the
* Accept-Encoding header, and SHOULD NOT be used in the Content-Encoding
* header.
*/
if (st->comp_algo->cfg_name_len != 8 || memcmp(st->comp_algo->cfg_name, "identity", 8) != 0) {
trash.data = 18;
memcpy(trash.area, "Content-Encoding: ", trash.data);
memcpy(trash.area + trash.data, st->comp_algo->ua_name,
st->comp_algo->ua_name_len);
trash.data += st->comp_algo->ua_name_len;
trash.area[trash.data] = '\0';
if (http_header_add_tail2(msg, &txn->hdr_idx, trash.area, trash.data) < 0)
goto error;
}
/* remove Content-Length header */
if (msg->flags & HTTP_MSGF_CNT_LEN) {
struct hdr_ctx ctx;
ctx.idx = 0;
while (http_find_header2("Content-Length", 14, ci_head(&s->res), &txn->hdr_idx, &ctx))
http_remove_header2(msg, &txn->hdr_idx, &ctx);
}
/* add Transfer-Encoding header */
if (!(msg->flags & HTTP_MSGF_TE_CHNK)) {
if (http_header_add_tail2(msg, &txn->hdr_idx, "Transfer-Encoding: chunked", 26) < 0)
goto error;
}
return 1;
error:
st->comp_algo->end(&st->comp_ctx);
st->comp_algo = NULL;
return 0;
}
static int
htx_set_comp_reshdr(struct comp_state *st, struct stream *s, struct http_msg *msg)
{
struct htx *htx = htxbuf(&msg->chn->buf);
/*
* Add Content-Encoding header when it's not identity encoding.
* RFC 2616 : Identity encoding: This content-coding is used only in the
* Accept-Encoding header, and SHOULD NOT be used in the Content-Encoding
* header.
*/
if (st->comp_algo->cfg_name_len != 8 || memcmp(st->comp_algo->cfg_name, "identity", 8) != 0) {
struct ist v = ist2(st->comp_algo->ua_name, st->comp_algo->ua_name_len);
if (!http_add_header(htx, ist("Content-Encoding"), v))
goto error;
}
/* remove Content-Length header */
if (msg->flags & HTTP_MSGF_CNT_LEN) {
struct http_hdr_ctx ctx;
ctx.blk = NULL;
while (http_find_header(htx, ist("Content-Length"), &ctx, 1))
http_remove_header(htx, &ctx);
}
/* add "Transfer-Encoding: chunked" header */
if (!(msg->flags & HTTP_MSGF_TE_CHNK)) {
if (!http_add_header(htx, ist("Transfer-Encoding"), ist("chunked")))
goto error;
}
return 1;
error:
st->comp_algo->end(&st->comp_ctx);
st->comp_algo = NULL;
return 0;
}
static int
set_compression_response_header(struct comp_state *st, struct stream *s, struct http_msg *msg)
{
if (IS_HTX_STRM(s))
return htx_set_comp_reshdr(st, s, msg);
else
return http_set_comp_reshdr(st, s, msg);
}
/*
* Selects a compression algorithm depending on the client request.
*/
static int
http_select_comp_reqhdr(struct comp_state *st, struct stream *s, struct http_msg *msg)
{
struct http_txn *txn = s->txn;
struct channel *req = msg->chn;
struct hdr_ctx ctx;
struct comp_algo *comp_algo = NULL;
struct comp_algo *comp_algo_back = NULL;
/* Disable compression for older user agents announcing themselves as "Mozilla/4"
* unless they are known good (MSIE 6 with XP SP2, or MSIE 7 and later).
* See http://zoompf.com/2012/02/lose-the-wait-http-compression for more details.
*/
ctx.idx = 0;
if (http_find_header2("User-Agent", 10, ci_head(req), &txn->hdr_idx, &ctx) &&
ctx.vlen >= 9 &&
memcmp(ctx.line + ctx.val, "Mozilla/4", 9) == 0 &&
(ctx.vlen < 31 ||
memcmp(ctx.line + ctx.val + 25, "MSIE ", 5) != 0 ||
ctx.line[ctx.val + 30] < '6' ||
(ctx.line[ctx.val + 30] == '6' &&
(ctx.vlen < 54 || memcmp(ctx.line + 51, "SV1", 3) != 0)))) {
st->comp_algo = NULL;
return 0;
}
/* search for the algo in the backend in priority or the frontend */
if ((s->be->comp && (comp_algo_back = s->be->comp->algos)) ||
(strm_fe(s)->comp && (comp_algo_back = strm_fe(s)->comp->algos))) {
int best_q = 0;
ctx.idx = 0;
while (http_find_header2("Accept-Encoding", 15, ci_head(req), &txn->hdr_idx, &ctx)) {
const char *qval;
int q;
int toklen;
/* try to isolate the token from the optional q-value */
toklen = 0;
while (toklen < ctx.vlen && HTTP_IS_TOKEN(*(ctx.line + ctx.val + toklen)))
toklen++;
qval = ctx.line + ctx.val + toklen;
while (1) {
while (qval < ctx.line + ctx.val + ctx.vlen && HTTP_IS_LWS(*qval))
qval++;
if (qval >= ctx.line + ctx.val + ctx.vlen || *qval != ';') {
qval = NULL;
break;
}
qval++;
while (qval < ctx.line + ctx.val + ctx.vlen && HTTP_IS_LWS(*qval))
qval++;
if (qval >= ctx.line + ctx.val + ctx.vlen) {
qval = NULL;
break;
}
if (strncmp(qval, "q=", MIN(ctx.line + ctx.val + ctx.vlen - qval, 2)) == 0)
break;
while (qval < ctx.line + ctx.val + ctx.vlen && *qval != ';')
qval++;
}
/* here we have qval pointing to the first "q=" attribute or NULL if not found */
q = qval ? http_parse_qvalue(qval + 2, NULL) : 1000;
if (q <= best_q)
continue;
for (comp_algo = comp_algo_back; comp_algo; comp_algo = comp_algo->next) {
if (*(ctx.line + ctx.val) == '*' ||
word_match(ctx.line + ctx.val, toklen, comp_algo->ua_name, comp_algo->ua_name_len)) {
st->comp_algo = comp_algo;
best_q = q;
break;
}
}
}
}
/* remove all occurrences of the header when "compression offload" is set */
if (st->comp_algo) {
if ((s->be->comp && s->be->comp->offload) ||
(strm_fe(s)->comp && strm_fe(s)->comp->offload)) {
http_remove_header2(msg, &txn->hdr_idx, &ctx);
ctx.idx = 0;
while (http_find_header2("Accept-Encoding", 15, ci_head(req), &txn->hdr_idx, &ctx)) {
http_remove_header2(msg, &txn->hdr_idx, &ctx);
}
}
return 1;
}
/* identity is implicit does not require headers */
if ((s->be->comp && (comp_algo_back = s->be->comp->algos)) ||
(strm_fe(s)->comp && (comp_algo_back = strm_fe(s)->comp->algos))) {
for (comp_algo = comp_algo_back; comp_algo; comp_algo = comp_algo->next) {
if (comp_algo->cfg_name_len == 8 && memcmp(comp_algo->cfg_name, "identity", 8) == 0) {
st->comp_algo = comp_algo;
return 1;
}
}
}
st->comp_algo = NULL;
return 0;
}
static int
htx_select_comp_reqhdr(struct comp_state *st, struct stream *s, struct http_msg *msg)
{
struct htx *htx = htxbuf(&msg->chn->buf);
struct http_hdr_ctx ctx;
struct comp_algo *comp_algo = NULL;
struct comp_algo *comp_algo_back = NULL;
/* Disable compression for older user agents announcing themselves as "Mozilla/4"
* unless they are known good (MSIE 6 with XP SP2, or MSIE 7 and later).
* See http://zoompf.com/2012/02/lose-the-wait-http-compression for more details.
*/
ctx.blk = NULL;
if (http_find_header(htx, ist("User-Agent"), &ctx, 1) &&
ctx.value.len >= 9 &&
memcmp(ctx.value.ptr, "Mozilla/4", 9) == 0 &&
(ctx.value.len < 31 ||
memcmp(ctx.value.ptr + 25, "MSIE ", 5) != 0 ||
*(ctx.value.ptr + 30) < '6' ||
(*(ctx.value.ptr + 30) == '6' &&
(ctx.value.len < 54 || memcmp(ctx.value.ptr + 51, "SV1", 3) != 0)))) {
st->comp_algo = NULL;
return 0;
}
/* search for the algo in the backend in priority or the frontend */
if ((s->be->comp && (comp_algo_back = s->be->comp->algos)) ||
(strm_fe(s)->comp && (comp_algo_back = strm_fe(s)->comp->algos))) {
int best_q = 0;
ctx.blk = NULL;
while (http_find_header(htx, ist("Accept-Encoding"), &ctx, 0)) {
const char *qval;
int q;
int toklen;
/* try to isolate the token from the optional q-value */
toklen = 0;
while (toklen < ctx.value.len && HTTP_IS_TOKEN(*(ctx.value.ptr + toklen)))
toklen++;
qval = ctx.value.ptr + toklen;
while (1) {
while (qval < ctx.value.ptr + ctx.value.len && HTTP_IS_LWS(*qval))
qval++;
if (qval >= ctx.value.ptr + ctx.value.len || *qval != ';') {
qval = NULL;
break;
}
qval++;
while (qval < ctx.value.ptr + ctx.value.len && HTTP_IS_LWS(*qval))
qval++;
if (qval >= ctx.value.ptr + ctx.value.len) {
qval = NULL;
break;
}
if (strncmp(qval, "q=", MIN(ctx.value.ptr + ctx.value.len - qval, 2)) == 0)
break;
while (qval < ctx.value.ptr + ctx.value.len && *qval != ';')
qval++;
}
/* here we have qval pointing to the first "q=" attribute or NULL if not found */
q = qval ? http_parse_qvalue(qval + 2, NULL) : 1000;
if (q <= best_q)
continue;
for (comp_algo = comp_algo_back; comp_algo; comp_algo = comp_algo->next) {
if (*(ctx.value.ptr) == '*' ||
word_match(ctx.value.ptr, toklen, comp_algo->ua_name, comp_algo->ua_name_len)) {
st->comp_algo = comp_algo;
best_q = q;
break;
}
}
}
}
/* remove all occurrences of the header when "compression offload" is set */
if (st->comp_algo) {
if ((s->be->comp && s->be->comp->offload) ||
(strm_fe(s)->comp && strm_fe(s)->comp->offload)) {
http_remove_header(htx, &ctx);
ctx.blk = NULL;
while (http_find_header(htx, ist("Accept-Encoding"), &ctx, 1))
http_remove_header(htx, &ctx);
}
return 1;
}
/* identity is implicit does not require headers */
if ((s->be->comp && (comp_algo_back = s->be->comp->algos)) ||
(strm_fe(s)->comp && (comp_algo_back = strm_fe(s)->comp->algos))) {
for (comp_algo = comp_algo_back; comp_algo; comp_algo = comp_algo->next) {
if (comp_algo->cfg_name_len == 8 && memcmp(comp_algo->cfg_name, "identity", 8) == 0) {
st->comp_algo = comp_algo;
return 1;
}
}
}
st->comp_algo = NULL;
return 0;
}
static int
select_compression_request_header(struct comp_state *st, struct stream *s,
struct http_msg *msg)
{
if (IS_HTX_STRM(s))
return htx_select_comp_reqhdr(st, s, msg);
else
return http_select_comp_reqhdr(st, s, msg);
}
/*
* Selects a comression algorithm depending of the server response.
*/
static int
http_select_comp_reshdr(struct comp_state *st, struct stream *s, struct http_msg *msg)
{
struct http_txn *txn = s->txn;
struct channel *c = msg->chn;
struct hdr_ctx ctx;
struct comp_type *comp_type;
/* no common compression algorithm was found in request header */
if (st->comp_algo == NULL)
goto fail;
/* HTTP < 1.1 should not be compressed */
if (!(msg->flags & HTTP_MSGF_VER_11) || !(txn->req.flags & HTTP_MSGF_VER_11))
goto fail;
if (txn->meth == HTTP_METH_HEAD)
goto fail;
/* compress 200,201,202,203 responses only */
if ((txn->status != 200) &&
(txn->status != 201) &&
(txn->status != 202) &&
(txn->status != 203))
goto fail;
/* Content-Length is null */
if (!(msg->flags & HTTP_MSGF_TE_CHNK) && msg->body_len == 0)
goto fail;
/* content is already compressed */
ctx.idx = 0;
if (http_find_header2("Content-Encoding", 16, ci_head(c), &txn->hdr_idx, &ctx))
goto fail;
/* no compression when Cache-Control: no-transform is present in the message */
ctx.idx = 0;
while (http_find_header2("Cache-Control", 13, ci_head(c), &txn->hdr_idx, &ctx)) {
if (word_match(ctx.line + ctx.val, ctx.vlen, "no-transform", 12))
goto fail;
}
comp_type = NULL;
/* we don't want to compress multipart content-types, nor content-types that are
* not listed in the "compression type" directive if any. If no content-type was
* found but configuration requires one, we don't compress either. Backend has
* the priority.
*/
ctx.idx = 0;
if (http_find_header2("Content-Type", 12, ci_head(c), &txn->hdr_idx, &ctx)) {
if (ctx.vlen >= 9 && strncasecmp("multipart", ctx.line+ctx.val, 9) == 0)
goto fail;
if ((s->be->comp && (comp_type = s->be->comp->types)) ||
(strm_fe(s)->comp && (comp_type = strm_fe(s)->comp->types))) {
for (; comp_type; comp_type = comp_type->next) {
if (ctx.vlen >= comp_type->name_len &&
strncasecmp(ctx.line+ctx.val, comp_type->name, comp_type->name_len) == 0)
/* this Content-Type should be compressed */
break;
}
/* this Content-Type should not be compressed */
if (comp_type == NULL)
goto fail;
}
}
else { /* no content-type header */
if ((s->be->comp && s->be->comp->types) ||
(strm_fe(s)->comp && strm_fe(s)->comp->types))
goto fail; /* a content-type was required */
}
/* limit compression rate */
if (global.comp_rate_lim > 0)
if (read_freq_ctr(&global.comp_bps_in) > global.comp_rate_lim)
goto fail;
/* limit cpu usage */
if (idle_pct < compress_min_idle)
goto fail;
/* initialize compression */
if (st->comp_algo->init(&st->comp_ctx, global.tune.comp_maxlevel) < 0)
goto fail;
msg->flags |= HTTP_MSGF_COMPRESSING;
return 1;
fail:
st->comp_algo = NULL;
return 0;
}
static int
htx_select_comp_reshdr(struct comp_state *st, struct stream *s, struct http_msg *msg)
{
struct htx *htx = htxbuf(&msg->chn->buf);
struct http_txn *txn = s->txn;
struct http_hdr_ctx ctx;
struct comp_type *comp_type;
/* no common compression algorithm was found in request header */
if (st->comp_algo == NULL)
goto fail;
/* HTTP < 1.1 should not be compressed */
if (!(msg->flags & HTTP_MSGF_VER_11) || !(txn->req.flags & HTTP_MSGF_VER_11))
goto fail;
if (txn->meth == HTTP_METH_HEAD)
goto fail;
/* compress 200,201,202,203 responses only */
if ((txn->status != 200) &&
(txn->status != 201) &&
(txn->status != 202) &&
(txn->status != 203))
goto fail;
if (msg->flags & HTTP_MSGF_BODYLESS)
goto fail;
/* content is already compressed */
ctx.blk = NULL;
if (http_find_header(htx, ist("Content-Encoding"), &ctx, 1))
goto fail;
/* no compression when Cache-Control: no-transform is present in the message */
ctx.blk = NULL;
while (http_find_header(htx, ist("Cache-Control"), &ctx, 0)) {
if (word_match(ctx.value.ptr, ctx.value.len, "no-transform", 12))
goto fail;
}
comp_type = NULL;
/* we don't want to compress multipart content-types, nor content-types that are
* not listed in the "compression type" directive if any. If no content-type was
* found but configuration requires one, we don't compress either. Backend has
* the priority.
*/
ctx.blk = NULL;
if (http_find_header(htx, ist("Content-Type"), &ctx, 1)) {
if (ctx.value.len >= 9 && strncasecmp("multipart", ctx.value.ptr, 9) == 0)
goto fail;
if ((s->be->comp && (comp_type = s->be->comp->types)) ||
(strm_fe(s)->comp && (comp_type = strm_fe(s)->comp->types))) {
for (; comp_type; comp_type = comp_type->next) {
if (ctx.value.len >= comp_type->name_len &&
strncasecmp(ctx.value.ptr, comp_type->name, comp_type->name_len) == 0)
/* this Content-Type should be compressed */
break;
}
/* this Content-Type should not be compressed */
if (comp_type == NULL)
goto fail;
}
}
else { /* no content-type header */
if ((s->be->comp && s->be->comp->types) ||
(strm_fe(s)->comp && strm_fe(s)->comp->types))
goto fail; /* a content-type was required */
}
/* limit compression rate */
if (global.comp_rate_lim > 0)
if (read_freq_ctr(&global.comp_bps_in) > global.comp_rate_lim)
goto fail;
/* limit cpu usage */
if (idle_pct < compress_min_idle)
goto fail;
/* initialize compression */
if (st->comp_algo->init(&st->comp_ctx, global.tune.comp_maxlevel) < 0)
goto fail;
msg->flags |= HTTP_MSGF_COMPRESSING;
return 1;
deinit_comp_ctx:
st->comp_algo->end(&st->comp_ctx);
fail:
st->comp_algo = NULL;
return 0;
}
static int
select_compression_response_header(struct comp_state *st, struct stream *s, struct http_msg *msg)
{
if (IS_HTX_STRM(s))
return htx_select_comp_reshdr(st, s, msg);
else
return http_select_comp_reshdr(st, s, msg);
}
/***********************************************************************/
/* emit the chunksize followed by a CRLF on the output and return the number of
* bytes written. It goes backwards and starts with the byte before <end>. It
* returns the number of bytes written which will not exceed 10 (8 digits, CR,
* and LF). The caller is responsible for ensuring there is enough room left in
* the output buffer for the string.
*/
static int
http_emit_chunk_size(char *end, unsigned int chksz)
{
char *beg = end;
*--beg = '\n';
*--beg = '\r';
do {
*--beg = hextab[chksz & 0xF];
} while (chksz >>= 4);
return end - beg;
}
/*
* Init HTTP compression
*/
static int
http_compression_buffer_init(struct channel *inc, struct buffer *out)
{
/* output stream requires at least 10 bytes for the gzip header, plus
* at least 8 bytes for the gzip trailer (crc+len), plus a possible
* plus at most 5 bytes per 32kB block and 2 bytes to close the stream.
*/
if (c_room(inc) < 20 + 5 * ((ci_data(inc) + 32767) >> 15))
return -1;
/* prepare an empty output buffer in which we reserve enough room for
* copying the output bytes from <in>, plus 10 extra bytes to write
* the chunk size. We don't copy the bytes yet so that if we have to
* cancel the operation later, it's cheap.
*/
b_reset(out);
out->head += co_data(inc) + 10;
return 0;
}
static int
htx_compression_buffer_init(struct htx *htx, struct buffer *out)
{
/* output stream requires at least 10 bytes for the gzip header, plus
* at least 8 bytes for the gzip trailer (crc+len), plus a possible
* plus at most 5 bytes per 32kB block and 2 bytes to close the stream.
*/
if (htx_free_space(htx) < 20 + 5 * ((htx->data + 32767) >> 15))
return -1;
b_reset(out);
return 0;
}
/*
* Add data to compress
*/
static int
http_compression_buffer_add_data(struct comp_state *st, struct buffer *in,
int in_out, struct buffer *out, int sz)
{
int consumed_data = 0;
int data_process_len;
int block1, block2;
if (!sz)
goto end;
/* select the smallest size between the announced chunk size, the input
* data, and the available output buffer size. The compressors are
* assumed to be able to process all the bytes we pass to them at
* once. */
data_process_len = MIN(b_room(out), sz);
block1 = data_process_len;
if (block1 > b_contig_data(in, in_out))
block1 = b_contig_data(in, in_out);
block2 = data_process_len - block1;
/* compressors return < 0 upon error or the amount of bytes read */
consumed_data = st->comp_algo->add_data(st->comp_ctx, b_peek(in, in_out), block1, out);
if (consumed_data != block1 || !block2)
goto end;
consumed_data = st->comp_algo->add_data(st->comp_ctx, b_orig(in), block2, out);
if (consumed_data < 0)
goto end;
consumed_data += block1;
end:
return consumed_data;
}
static int
htx_compression_buffer_add_data(struct comp_state *st, const char *data, size_t len,
struct buffer *out)
{
return st->comp_algo->add_data(st->comp_ctx, data, len, out);
}
/*
* Flush data in process, and write the header and footer of the chunk. Upon
* success, in and out buffers are swapped to avoid a copy.
*/
static int
http_compression_buffer_end(struct comp_state *st, struct stream *s,
struct channel *chn, struct buffer *out,
int end)
{
struct buffer tmp_buf;
char *tail;
int to_forward, left;
#if defined(USE_SLZ) || defined(USE_ZLIB)
int ret;
/* flush data here */
if (end)
ret = st->comp_algo->finish(st->comp_ctx, out); /* end of data */
else
ret = st->comp_algo->flush(st->comp_ctx, out); /* end of buffer */
if (ret < 0)
return -1; /* flush failed */
#endif /* USE_ZLIB */
if (b_data(out) == 0) {
/* No data were appended, let's drop the output buffer and
* keep the input buffer unchanged.
*/
return 0;
}
/* OK so at this stage, we have an output buffer <out> looking like this :
*
* <-- o --> <------ i ----->
* +---------+---+------------+-----------+
* | out | c | comp_in | empty |
* +---------+---+------------+-----------+
* data p size
*
* <out> is the room reserved to copy the channel output. It starts at
* out->area and has not yet been filled. <c> is the room reserved to
* write the chunk size (10 bytes). <comp_in> is the compressed
* equivalent of the data part of ib->len. <empty> is the amount of
* empty bytes at the end of the buffer, into which we may have to
* copy the remaining bytes from ib->len after the data
* (chunk size, trailers, ...).
*/
/* Write real size at the beginning of the chunk, no need of wrapping.
* We write the chunk using a dynamic length and adjust out->p and out->i
* accordingly afterwards. That will move <out> away from <data>.
*/
left = http_emit_chunk_size(b_head(out), b_data(out));
b_add(out, left);
out->head -= co_data(chn) + (left);
/* Copy previous data from chn into out */
if (co_data(chn) > 0) {
left = b_contig_data(&chn->buf, 0);
if (left > co_data(chn))
left = co_data(chn);
memcpy(b_head(out), co_head(chn), left);
b_add(out, left);
if (co_data(chn) - left) {/* second part of the buffer */
memcpy(b_head(out) + left, b_orig(&chn->buf), co_data(chn) - left);
b_add(out, co_data(chn) - left);
}
}
/* chunked encoding requires CRLF after data */
tail = b_tail(out);
*tail++ = '\r';
*tail++ = '\n';
/* At the end of data, we must write the empty chunk 0<CRLF>,
* and terminate the trailers section with a last <CRLF>. If
* we're forwarding a chunked-encoded response, we'll have a
* trailers section after the empty chunk which needs to be
* forwarded and which will provide the last CRLF. Otherwise
* we write it ourselves.
*/
if (end) {
struct http_msg *msg = &s->txn->rsp;
memcpy(tail, "0\r\n", 3);
tail += 3;
if (!(msg->flags & HTTP_MSGF_TE_CHNK)) {
memcpy(tail, "\r\n", 2);
tail += 2;
}
}
b_add(out, tail - b_tail(out));
to_forward = b_data(out) - co_data(chn);
/* update input rate */
if (st->comp_ctx && st->comp_ctx->cur_lvl > 0) {
update_freq_ctr(&global.comp_bps_in, st->consumed);
HA_ATOMIC_ADD(&strm_fe(s)->fe_counters.comp_in, st->consumed);
HA_ATOMIC_ADD(&s->be->be_counters.comp_in, st->consumed);
} else {
HA_ATOMIC_ADD(&strm_fe(s)->fe_counters.comp_byp, st->consumed);
HA_ATOMIC_ADD(&s->be->be_counters.comp_byp, st->consumed);
}
/* copy the remaining data in the tmp buffer. */
c_adv(chn, st->consumed);
if (b_data(&chn->buf) - co_data(chn) > 0) {
left = ci_contig_data(chn);
memcpy(b_tail(out), ci_head(chn), left);
b_add(out, left);
if (b_data(&chn->buf) - (co_data(chn) + left)) {
memcpy(b_tail(out), b_orig(&chn->buf), b_data(&chn->buf) - left);
b_add(out, b_data(&chn->buf) - left);
}
}
c_rew(chn, st->consumed);
/* swap the buffers */
tmp_buf = chn->buf;
chn->buf = *out;
*out = tmp_buf;
if (st->comp_ctx && st->comp_ctx->cur_lvl > 0) {
update_freq_ctr(&global.comp_bps_out, to_forward);
HA_ATOMIC_ADD(&strm_fe(s)->fe_counters.comp_out, to_forward);
HA_ATOMIC_ADD(&s->be->be_counters.comp_out, to_forward);
}
return to_forward;
}
static int
htx_compression_buffer_end(struct comp_state *st, struct buffer *out, int end)
{
if (end)
return st->comp_algo->finish(st->comp_ctx, out);
else
return st->comp_algo->flush(st->comp_ctx, out);
}
/***********************************************************************/
struct flt_ops comp_ops = {
.init = comp_flt_init,
.init_per_thread = comp_flt_init_per_thread,
.deinit_per_thread = comp_flt_deinit_per_thread,
.channel_start_analyze = comp_start_analyze,
.channel_end_analyze = comp_end_analyze,
.channel_post_analyze = comp_http_post_analyze,
.http_headers = comp_http_headers,
.http_payload = comp_http_payload,
.http_end = comp_http_end,
.http_data = comp_http_data,
.http_chunk_trailers = comp_http_chunk_trailers,
.http_forward_data = comp_http_forward_data,
};
static int
parse_compression_options(char **args, int section, struct proxy *proxy,
struct proxy *defpx, const char *file, int line,
char **err)
{
struct comp *comp;
if (proxy->comp == NULL) {
comp = calloc(1, sizeof(*comp));
proxy->comp = comp;
}
else
comp = proxy->comp;
if (!strcmp(args[1], "algo")) {
struct comp_ctx *ctx;
int cur_arg = 2;
if (!*args[cur_arg]) {
memprintf(err, "parsing [%s:%d] : '%s' expects <algorithm>\n",
file, line, args[0]);
return -1;
}
while (*(args[cur_arg])) {
if (comp_append_algo(comp, args[cur_arg]) < 0) {
memprintf(err, "'%s' : '%s' is not a supported algorithm.\n",
args[0], args[cur_arg]);
return -1;
}
if (proxy->comp->algos->init(&ctx, 9) == 0)
proxy->comp->algos->end(&ctx);
else {
memprintf(err, "'%s' : Can't init '%s' algorithm.\n",
args[0], args[cur_arg]);
return -1;
}
cur_arg++;
continue;
}
}
else if (!strcmp(args[1], "offload"))
comp->offload = 1;
else if (!strcmp(args[1], "type")) {
int cur_arg = 2;
if (!*args[cur_arg]) {
memprintf(err, "'%s' expects <type>\n", args[0]);
return -1;
}
while (*(args[cur_arg])) {
comp_append_type(comp, args[cur_arg]);
cur_arg++;
continue;
}
}
else {
memprintf(err, "'%s' expects 'algo', 'type' or 'offload'\n",
args[0]);
return -1;
}
return 0;
}
static int
parse_http_comp_flt(char **args, int *cur_arg, struct proxy *px,
struct flt_conf *fconf, char **err, void *private)
{
struct flt_conf *fc, *back;
list_for_each_entry_safe(fc, back, &px->filter_configs, list) {
if (fc->id == http_comp_flt_id) {
memprintf(err, "%s: Proxy supports only one compression filter\n", px->id);
return -1;
}
}
fconf->id = http_comp_flt_id;
fconf->conf = NULL;
fconf->ops = &comp_ops;
(*cur_arg)++;
return 0;
}
int
check_implicit_http_comp_flt(struct proxy *proxy)
{
struct flt_conf *fconf;
int explicit = 0;
int comp = 0;
int err = 0;
if (proxy->comp == NULL)
goto end;
if (!LIST_ISEMPTY(&proxy->filter_configs)) {
list_for_each_entry(fconf, &proxy->filter_configs, list) {
if (fconf->id == http_comp_flt_id)
comp = 1;
else if (fconf->id == cache_store_flt_id) {
if (comp) {
ha_alert("config: %s '%s': unable to enable the compression filter "
"before any cache filter.\n",
proxy_type_str(proxy), proxy->id);
err++;
goto end;
}
}
else
explicit = 1;
}
}
if (comp)
goto end;
else if (explicit) {
ha_alert("config: %s '%s': require an explicit filter declaration to use "
"HTTP compression\n", proxy_type_str(proxy), proxy->id);
err++;
goto end;
}
/* Implicit declaration of the compression filter is always the last
* one */
fconf = calloc(1, sizeof(*fconf));
if (!fconf) {
ha_alert("config: %s '%s': out of memory\n",
proxy_type_str(proxy), proxy->id);
err++;
goto end;
}
fconf->id = http_comp_flt_id;
fconf->conf = NULL;
fconf->ops = &comp_ops;
LIST_ADDQ(&proxy->filter_configs, &fconf->list);
end:
return err;
}
/*
* boolean, returns true if compression is used (either gzip or deflate) in the
* response.
*/
static int
smp_fetch_res_comp(const struct arg *args, struct sample *smp, const char *kw,
void *private)
{
struct http_txn *txn = smp->strm ? smp->strm->txn : NULL;
smp->data.type = SMP_T_BOOL;
smp->data.u.sint = (txn && (txn->rsp.flags & HTTP_MSGF_COMPRESSING));
return 1;
}
/*
* string, returns algo
*/
static int
smp_fetch_res_comp_algo(const struct arg *args, struct sample *smp,
const char *kw, void *private)
{
struct http_txn *txn = smp->strm ? smp->strm->txn : NULL;
struct filter *filter;
struct comp_state *st;
if (!txn || !(txn->rsp.flags & HTTP_MSGF_COMPRESSING))
return 0;
list_for_each_entry(filter, &strm_flt(smp->strm)->filters, list) {
if (FLT_ID(filter) != http_comp_flt_id)
continue;
if (!(st = filter->ctx))
break;
smp->data.type = SMP_T_STR;
smp->flags = SMP_F_CONST;
smp->data.u.str.area = st->comp_algo->cfg_name;
smp->data.u.str.data = st->comp_algo->cfg_name_len;
return 1;
}
return 0;
}
/* Declare the config parser for "compression" keyword */
static struct cfg_kw_list cfg_kws = {ILH, {
{ CFG_LISTEN, "compression", parse_compression_options },
{ 0, NULL, NULL },
}
};
INITCALL1(STG_REGISTER, cfg_register_keywords, &cfg_kws);
/* Declare the filter parser for "compression" keyword */
static struct flt_kw_list filter_kws = { "COMP", { }, {
{ "compression", parse_http_comp_flt, NULL },
{ NULL, NULL, NULL },
}
};
INITCALL1(STG_REGISTER, flt_register_keywords, &filter_kws);
/* Note: must not be declared <const> as its list will be overwritten */
static struct sample_fetch_kw_list sample_fetch_keywords = {ILH, {
{ "res.comp", smp_fetch_res_comp, 0, NULL, SMP_T_BOOL, SMP_USE_HRSHP },
{ "res.comp_algo", smp_fetch_res_comp_algo, 0, NULL, SMP_T_STR, SMP_USE_HRSHP },
{ /* END */ },
}
};
INITCALL1(STG_REGISTER, sample_register_fetches, &sample_fetch_keywords);