lighttpd 1.4.x https://www.lighttpd.net/
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#include "first.h"
#include "sys-time.h"
#include "base.h"
#include "array.h"
#include "buffer.h"
#include "chunk.h"
#include "fdevent.h"
#include "log.h"
#include "http_chunk.h"
#include "http_cgi.h"
#include "http_date.h"
#include "http_etag.h"
#include "http_header.h"
#include "response.h"
#include "sock_addr.h"
#include "stat_cache.h"
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include "sys-socket.h"
#include <unistd.h>
/**
* max size of the HTTP response header from backends
* (differs from server.max-request-field-size for max request field size)
*/
#define MAX_HTTP_RESPONSE_FIELD_SIZE 65535
__attribute_cold__
int http_response_buffer_append_authority(request_st * const r, buffer * const o) {
if (!buffer_is_blank(&r->uri.authority)) {
buffer_append_string_buffer(o, &r->uri.authority);
} else {
/* get the name of the currently connected socket */
sock_addr our_addr;
socklen_t our_addr_len;
our_addr.plain.sa_family = 0;
our_addr_len = sizeof(our_addr);
if (-1 == getsockname(r->con->fd, (struct sockaddr *)&our_addr, &our_addr_len)
|| our_addr_len > (socklen_t)sizeof(our_addr)) {
r->http_status = 500;
log_perror(r->conf.errh, __FILE__, __LINE__, "can't get sockname");
return -1;
}
if (our_addr.plain.sa_family == AF_INET
&& our_addr.ipv4.sin_addr.s_addr == htonl(INADDR_LOOPBACK)) {
static char lhost[32];
static size_t lhost_len = 0;
if (0 != lhost_len) {
buffer_append_string_len(o, lhost, lhost_len);
}
else {
size_t olen = buffer_clen(o);
if (0 == sock_addr_nameinfo_append_buffer(o, &our_addr, r->conf.errh)) {
lhost_len = buffer_clen(o) - olen;
if (lhost_len < sizeof(lhost)) {
memcpy(lhost, o->ptr+olen, lhost_len+1); /*(+1 for '\0')*/
}
else {
lhost_len = 0;
}
}
else {
lhost_len = sizeof("localhost")-1;
memcpy(lhost, "localhost", lhost_len+1); /*(+1 for '\0')*/
buffer_append_string_len(o, lhost, lhost_len);
}
}
} else if (!buffer_is_blank(r->server_name)) {
buffer_append_string_buffer(o, r->server_name);
} else
/* Lookup name: secondly try to get hostname for bind address */
if (0 != sock_addr_nameinfo_append_buffer(o, &our_addr, r->conf.errh)) {
r->http_status = 500;
return -1;
}
{
unsigned short listen_port = sock_addr_get_port(&our_addr);
unsigned short default_port = 80;
if (buffer_is_equal_string(&r->uri.scheme, CONST_STR_LEN("https"))) {
default_port = 443;
}
if (0 == listen_port) listen_port = r->con->srv->srvconf.port;
if (default_port != listen_port) {
buffer_append_string_len(o, CONST_STR_LEN(":"));
buffer_append_int(o, listen_port);
}
}
}
return 0;
}
int http_response_redirect_to_directory(request_st * const r, int status) {
buffer *o = r->tmp_buf;
buffer_clear(o);
/* XXX: store flag in global at startup? */
if (r->con->srv->srvconf.absolute_dir_redirect) {
buffer_append_str2(o, BUF_PTR_LEN(&r->uri.scheme),
CONST_STR_LEN("://"));
if (0 != http_response_buffer_append_authority(r, o)) {
return -1;
}
}
buffer *vb;
if (status >= 300) {
r->http_status = status;
r->resp_body_finished = 1;
vb = http_header_response_set_ptr(r, HTTP_HEADER_LOCATION,
CONST_STR_LEN("Location"));
}
else {
vb = http_header_response_set_ptr(r, HTTP_HEADER_CONTENT_LOCATION,
CONST_STR_LEN("Content-Location"));
}
buffer_copy_buffer(vb, o);
buffer_append_string_encoded(vb, BUF_PTR_LEN(&r->uri.path),
ENCODING_REL_URI);
buffer_append_string_len(vb, CONST_STR_LEN("/"));
if (!buffer_is_blank(&r->uri.query))
buffer_append_str2(vb, CONST_STR_LEN("?"),
BUF_PTR_LEN(&r->uri.query));
return 0;
}
#define MTIME_CACHE_MAX 16
struct mtime_cache_type {
unix_time64_t mtime; /* key */
buffer str; /* buffer for string representation */
};
static struct mtime_cache_type mtime_cache[MTIME_CACHE_MAX];
static char mtime_cache_str[MTIME_CACHE_MAX][HTTP_DATE_SZ];
/* 30-chars for "%a, %d %b %Y %T GMT" */
void strftime_cache_reset(void) {
for (int i = 0; i < MTIME_CACHE_MAX; ++i) {
mtime_cache[i].mtime = -1;
mtime_cache[i].str.ptr = mtime_cache_str[i];
mtime_cache[i].str.used = sizeof(mtime_cache_str[0]);
mtime_cache[i].str.size = sizeof(mtime_cache_str[0]);
}
}
static const buffer * strftime_cache_get(const unix_time64_t last_mod) {
/*(note: not bothering to convert *here* if last_mod < 0 (for cache key);
* last_mod < 0 handled in http_date_time_to_str() call to gmtime64_r())*/
static int mtime_cache_idx;
for (int j = 0; j < MTIME_CACHE_MAX; ++j) {
if (mtime_cache[j].mtime == last_mod)
return &mtime_cache[j].str; /* found cache-entry */
}
if (++mtime_cache_idx == MTIME_CACHE_MAX) mtime_cache_idx = 0;
const int i = mtime_cache_idx;
http_date_time_to_str(mtime_cache[i].str.ptr, sizeof(mtime_cache_str[0]),
(mtime_cache[i].mtime = last_mod));
return &mtime_cache[i].str;
}
const buffer * http_response_set_last_modified(request_st * const r, const unix_time64_t lmtime) {
buffer * const vb =
http_header_response_set_ptr(r, HTTP_HEADER_LAST_MODIFIED,
CONST_STR_LEN("Last-Modified"));
buffer_copy_buffer(vb, strftime_cache_get(lmtime));
return vb;
}
int http_response_handle_cachable(request_st * const r, const buffer * const lmod, const unix_time64_t lmtime) {
if (!(r->rqst_htags
& (light_bshift(HTTP_HEADER_IF_NONE_MATCH)
|light_bshift(HTTP_HEADER_IF_MODIFIED_SINCE)))) {
return HANDLER_GO_ON;
}
const buffer *vb;
/*
* 14.26 If-None-Match
* [...]
* If none of the entity tags match, then the server MAY perform the
* requested method as if the If-None-Match header field did not exist,
* but MUST also ignore any If-Modified-Since header field(s) in the
* request. That is, if no entity tags match, then the server MUST NOT
* return a 304 (Not Modified) response.
*/
if ((vb = http_header_request_get(r, HTTP_HEADER_IF_NONE_MATCH,
CONST_STR_LEN("If-None-Match")))) {
/*(weak etag comparison must not be used for ranged requests)*/
int range_request = (0 != light_btst(r->rqst_htags, HTTP_HEADER_RANGE));
if (http_etag_matches(&r->physical.etag, vb->ptr, !range_request)) {
if (http_method_get_or_head(r->http_method)) {
r->http_status = 304;
return HANDLER_FINISHED;
} else {
r->http_status = 412;
r->handler_module = NULL;
return HANDLER_FINISHED;
}
}
} else if (http_method_get_or_head(r->http_method)
&& (vb = http_header_request_get(r, HTTP_HEADER_IF_MODIFIED_SINCE,
CONST_STR_LEN("If-Modified-Since")))) {
/* last-modified handling */
if (buffer_is_equal(lmod, vb)
|| !http_date_if_modified_since(BUF_PTR_LEN(vb), lmtime)) {
r->http_status = 304;
return HANDLER_FINISHED;
}
}
return HANDLER_GO_ON;
}
void http_response_body_clear (request_st * const r, int preserve_length) {
r->resp_send_chunked = 0;
r->resp_body_scratchpad = -1;
if (light_btst(r->resp_htags, HTTP_HEADER_TRANSFER_ENCODING)) {
http_header_response_unset(r, HTTP_HEADER_TRANSFER_ENCODING,
CONST_STR_LEN("Transfer-Encoding"));
}
if (!preserve_length) { /* preserve for HEAD responses and no-content responses (204, 205, 304) */
if (light_btst(r->resp_htags, HTTP_HEADER_CONTENT_LENGTH)) {
http_header_response_unset(r, HTTP_HEADER_CONTENT_LENGTH,
CONST_STR_LEN("Content-Length"));
}
/*(if not preserving Content-Length, do not preserve trailers, if any)*/
r->resp_decode_chunked = 0;
if (r->gw_dechunk) {
free(r->gw_dechunk->b.ptr);
free(r->gw_dechunk);
r->gw_dechunk = NULL;
}
}
chunkqueue_reset(&r->write_queue);
}
static void http_response_header_clear (request_st * const r) {
r->http_status = 0;
r->resp_htags = 0;
r->resp_header_len = 0;
r->resp_header_repeated = 0;
array_reset_data_strings(&r->resp_headers);
/* Note: http_response_body_clear(r, 0) is not called here
* r->write_queue should be preserved for additional data after 1xx response
* However, if http_response_process_headers() was called and response had
* Transfer-Encoding: chunked set, then other items need to be reset */
r->resp_send_chunked = 0;
r->resp_decode_chunked = 0;
r->resp_body_scratchpad = -1;
if (r->gw_dechunk) {
free(r->gw_dechunk->b.ptr);
free(r->gw_dechunk);
r->gw_dechunk = NULL;
}
}
void http_response_reset (request_st * const r) {
r->http_status = 0;
r->con->is_writable = 1;
r->resp_body_finished = 0;
r->resp_body_started = 0;
r->handler_module = NULL;
if (r->physical.path.ptr) { /*(skip for mod_fastcgi authorizer)*/
buffer_clear(&r->physical.doc_root);
buffer_clear(&r->physical.basedir);
buffer_clear(&r->physical.etag);
buffer_reset(&r->physical.path);
buffer_reset(&r->physical.rel_path);
}
r->resp_htags = 0;
r->resp_header_len = 0;
r->resp_header_repeated = 0;
array_reset_data_strings(&r->resp_headers);
http_response_body_clear(r, 0);
}
handler_t http_response_reqbody_read_error (request_st * const r, int http_status) {
r->keep_alive = 0;
/*(do not change status if response headers already set and possibly sent)*/
if (0 != r->resp_header_len) return HANDLER_ERROR;
http_response_body_clear(r, 0);
r->http_status = http_status;
r->handler_module = NULL;
return HANDLER_FINISHED;
}
void http_response_send_file (request_st * const r, buffer * const path, stat_cache_entry *sce) {
if (NULL == sce
|| (sce->fd < 0 && __builtin_expect( (0 != sce->st.st_size), 0))) {
sce = stat_cache_get_entry_open(path, r->conf.follow_symlink);
if (NULL == sce) {
r->http_status = (errno == ENOENT) ? 404 : 403;
log_error(r->conf.errh, __FILE__, __LINE__,
"not a regular file: %s -> %s", r->uri.path.ptr, path->ptr);
return;
}
if (sce->fd < 0 && __builtin_expect( (0 != sce->st.st_size), 0)) {
r->http_status = (errno == ENOENT) ? 404 : 403;
if (r->conf.log_request_handling) {
log_perror(r->conf.errh, __FILE__, __LINE__,
"file open failed: %s", path->ptr);
}
return;
}
}
if (__builtin_expect( (!r->conf.follow_symlink), 0)
&& 0 != stat_cache_path_contains_symlink(path, r->conf.errh)) {
r->http_status = 403;
if (r->conf.log_request_handling) {
log_error(r->conf.errh, __FILE__, __LINE__,
"-- access denied due symlink restriction");
log_error(r->conf.errh, __FILE__, __LINE__,
"Path : %s", path->ptr);
}
return;
}
/* we only handle regular files */
if (__builtin_expect( (!S_ISREG(sce->st.st_mode)), 0)) {
r->http_status = 403;
if (r->conf.log_file_not_found) {
log_error(r->conf.errh, __FILE__, __LINE__,
"not a regular file: %s -> %s",
r->uri.path.ptr, path->ptr);
}
return;
}
int allow_caching = (0 == r->http_status || 200 == r->http_status);
/* set response content-type, if not set already */
if (!light_btst(r->resp_htags, HTTP_HEADER_CONTENT_TYPE)) {
const buffer *content_type = stat_cache_content_type_get(sce, r);
if (content_type && !buffer_is_blank(content_type)) {
http_header_response_set(r, HTTP_HEADER_CONTENT_TYPE,
CONST_STR_LEN("Content-Type"),
BUF_PTR_LEN(content_type));
} else {
/* we are setting application/octet-stream, but also announce that
* this header field might change in the seconds few requests
*
* This should fix the aggressive caching of FF and the script download
* seen by the first installations
*/
http_header_response_set(r, HTTP_HEADER_CONTENT_TYPE,
CONST_STR_LEN("Content-Type"),
CONST_STR_LEN("application/octet-stream"));
allow_caching = 0;
}
}
if (allow_caching) {
if (!light_btst(r->resp_htags, HTTP_HEADER_ETAG)
&& 0 != r->conf.etag_flags) {
const buffer *etag =
stat_cache_etag_get(sce, r->conf.etag_flags);
if (etag && !buffer_is_blank(etag)) {
buffer_copy_buffer(&r->physical.etag, etag);
http_header_response_set(r, HTTP_HEADER_ETAG,
CONST_STR_LEN("ETag"),
BUF_PTR_LEN(&r->physical.etag));
}
}
/* prepare header */
const buffer *mtime;
mtime = http_header_response_get(r, HTTP_HEADER_LAST_MODIFIED,
CONST_STR_LEN("Last-Modified"));
if (NULL == mtime) {
mtime = http_response_set_last_modified(r, sce->st.st_mtime);
}
if (HANDLER_FINISHED == http_response_handle_cachable(r, mtime, sce->st.st_mtime)) {
return;
}
}
/* if we are still here, prepare body */
/* we add it here for all requests
* the HEAD request will drop it afterwards again
*/
if (0 == sce->st.st_size || 0 == http_chunk_append_file_ref(r, sce)) {
r->http_status = 200;
r->resp_body_finished = 1;
/*(Transfer-Encoding should not have been set at this point)*/
buffer_append_int(
http_header_response_set_ptr(r, HTTP_HEADER_CONTENT_LENGTH,
CONST_STR_LEN("Content-Length")),
sce->st.st_size);
}
else {
r->http_status = 500;
}
}
static void http_response_xsendfile (request_st * const r, buffer * const path, const array * const xdocroot) {
const int status = r->http_status;
int valid = 1;
/* reset Content-Length, if set by backend
* Content-Length might later be set to size of X-Sendfile static file,
* determined by open(), fstat() to reduces race conditions if the file
* is modified between stat() (stat_cache_get_entry()) and open(). */
if (light_btst(r->resp_htags, HTTP_HEADER_CONTENT_LENGTH)) {
http_header_response_unset(r, HTTP_HEADER_CONTENT_LENGTH,
CONST_STR_LEN("Content-Length"));
}
buffer_urldecode_path(path);
if (!buffer_is_valid_UTF8(path)) {
log_error(r->conf.errh, __FILE__, __LINE__,
"X-Sendfile invalid UTF-8 after url-decode: %s", path->ptr);
if (r->http_status < 400) {
r->http_status = 502;
r->handler_module = NULL;
}
return;
}
buffer_path_simplify(path);
if (r->conf.force_lowercase_filenames) {
buffer_to_lower(path);
}
if (buffer_is_blank(path)) {
r->http_status = 502;
valid = 0;
}
/* check that path is under xdocroot(s)
* - xdocroot should have trailing slash appended at config time
* - r->conf.force_lowercase_filenames is not a server-wide setting,
* and so can not be definitively applied to xdocroot at config time*/
if (xdocroot && xdocroot->used) {
const buffer * const xval = !r->conf.force_lowercase_filenames
? array_match_value_prefix(xdocroot, path)
: array_match_value_prefix_nc(xdocroot, path);
if (NULL == xval) {
log_error(r->conf.errh, __FILE__, __LINE__,
"X-Sendfile (%s) not under configured x-sendfile-docroot(s)", path->ptr);
r->http_status = 403;
valid = 0;
}
}
if (valid) http_response_send_file(r, path, NULL);
if (r->http_status >= 400 && status < 300) {
r->handler_module = NULL;
} else if (0 != status && 200 != status) {
r->http_status = status;
}
}
static void http_response_xsendfile2(request_st * const r, const buffer * const value, const array * const xdocroot) {
const char *pos = value->ptr;
buffer * const b = r->tmp_buf;
const int status = r->http_status;
/* reset Content-Length, if set by backend */
if (light_btst(r->resp_htags, HTTP_HEADER_CONTENT_LENGTH)) {
http_header_response_unset(r, HTTP_HEADER_CONTENT_LENGTH,
CONST_STR_LEN("Content-Length"));
}
while (*pos) {
const char *filename, *range;
stat_cache_entry *sce;
off_t begin_range, end_range, range_len;
while (' ' == *pos) pos++;
if (!*pos) break;
filename = pos;
if (NULL == (range = strchr(pos, ' '))) {
/* missing range */
log_error(r->conf.errh, __FILE__, __LINE__,
"Couldn't find range after filename: %s", filename);
r->http_status = 502;
break;
}
buffer_copy_string_len(b, filename, range - filename);
/* find end of range */
for (pos = ++range; *pos && *pos != ' ' && *pos != ','; pos++) ;
buffer_urldecode_path(b);
if (!buffer_is_valid_UTF8(b)) {
log_error(r->conf.errh, __FILE__, __LINE__,
"X-Sendfile2 invalid UTF-8 after url-decode: %s", b->ptr);
r->http_status = 502;
break;
}
buffer_path_simplify(b);
if (r->conf.force_lowercase_filenames) {
buffer_to_lower(b);
}
if (buffer_is_blank(b)) {
r->http_status = 502;
break;
}
if (xdocroot && xdocroot->used) {
const buffer * const xval = !r->conf.force_lowercase_filenames
? array_match_value_prefix(xdocroot, b)
: array_match_value_prefix_nc(xdocroot, b);
if (NULL == xval) {
log_error(r->conf.errh, __FILE__, __LINE__,
"X-Sendfile2 (%s) not under configured x-sendfile-docroot(s)",
b->ptr);
r->http_status = 403;
break;
}
}
sce = stat_cache_get_entry_open(b, r->conf.follow_symlink);
if (NULL == sce) {
log_error(r->conf.errh, __FILE__, __LINE__,
"send-file error: couldn't get stat_cache entry for "
"X-Sendfile2: %s", b->ptr);
r->http_status = 404;
break;
} else if (!S_ISREG(sce->st.st_mode)) {
log_error(r->conf.errh, __FILE__, __LINE__,
"send-file error: wrong filetype for X-Sendfile2: %s", b->ptr);
r->http_status = 502;
break;
}
/* found the file */
/* parse range */
end_range = sce->st.st_size - 1;
{
char *rpos = NULL;
errno = 0;
begin_range = strtoll(range, &rpos, 10);
if (errno != 0 || begin_range < 0 || rpos == range)
goto range_failed;
if ('-' != *rpos++) goto range_failed;
if (rpos != pos) {
range = rpos;
end_range = strtoll(range, &rpos, 10);
if (errno != 0 || end_range < 0 || rpos == range)
goto range_failed;
}
if (rpos != pos) goto range_failed;
goto range_success;
range_failed:
log_error(r->conf.errh, __FILE__, __LINE__,
"Couldn't decode range after filename: %s", filename);
r->http_status = 502;
break;
range_success: ;
}
/* no parameters accepted */
while (*pos == ' ') pos++;
if (*pos != '\0' && *pos != ',') {
r->http_status = 502;
break;
}
range_len = end_range - begin_range + 1;
if (range_len < 0) {
r->http_status = 502;
break;
}
if (range_len != 0) {
http_chunk_append_file_ref_range(r, sce, begin_range, range_len);
}
if (*pos == ',') pos++;
}
if (r->http_status >= 400 && status < 300) {
r->handler_module = NULL;
} else if (0 != status && 200 != status) {
r->http_status = status;
}
}
void http_response_backend_error (request_st * const r) {
if (r->resp_body_started) {
/*(response might have been already started, kill the connection)*/
/*(mode == DIRECT to avoid later call to http_response_backend_done())*/
r->handler_module = NULL; /*(avoid sending final chunked block)*/
r->keep_alive = 0;
r->resp_body_finished = 1;
} /*(else error status set later by http_response_backend_done())*/
}
void http_response_backend_done (request_st * const r) {
/* (not CON_STATE_ERROR and not CON_STATE_RESPONSE_END,
* i.e. not called from handle_connection_close or handle_request_reset
* hooks, except maybe from errdoc handler, which later resets state)*/
switch (r->state) {
case CON_STATE_HANDLE_REQUEST:
case CON_STATE_READ_POST:
if (!r->resp_body_started) {
/* Send an error if we haven't sent any data yet */
if (r->http_status < 500 && r->http_status != 400)
r->http_status = 500;
r->handler_module = NULL;
break;
}
__attribute_fallthrough__
case CON_STATE_WRITE:
if (!r->resp_body_finished) {
if (r->http_version == HTTP_VERSION_1_1)
http_chunk_close(r);
#if 0
/* This is a lot of work to make it possible for an HTTP/1.0 client
* to detect that response is truncated (after lighttpd made an
* HTTP/1.1 request to backend, and backend gave a Transfer-Encoding
* chunked response instead of sending Content-Length, and lighttpd
* is streaming response to client). An HTTP/1.0 client is probably
* not checking for truncated response, or else client should really
* prefer HTTP/1.1 or better. If lighttpd were streaming response,
* there would be no Content-Length and lighttpd would have sent
* Connection: close. Alternatively, since not streaming (if these
* conditions are true), could send an HTTP status error instead of
* sending partial content with a bogus Content-Length. If we do
* not send an HTTP error status, then response_start hooks may add
* caching headers (e.g. mod_expire, mod_setenv). If in future we
* send HTTP error status, might special-case HEAD requests and
* clear response body so that response headers (w/o Content-Length)
* can be sent. For now, we have chosen to send partial content,
* including generating an incorrect Content-Length (later), and not
* to take any of these extra steps. */
else if (__builtin_expect( (r->http_version == HTTP_VERSION_1_0), 0)
&& r->gw_dechunk && !r->gw_dechunk->done
&& !(r->conf.stream_response_body
& (FDEVENT_STREAM_RESPONSE
|FDEVENT_STREAM_RESPONSE_BUFMIN))) {
r->keep_alive = 0; /* disable keep-alive, send bogus length */
http_header_response_set(r, HTTP_HEADER_CONTENT_LENGTH,
CONST_STR_LEN("Content-Length"),
CONST_STR_LEN("9999999999999"));
http_header_response_unset(r, HTTP_HEADER_ETAG,
CONST_STR_LEN("ETag"));
http_header_response_unset(r, HTTP_HEADER_LAST_MODIFIED,
CONST_STR_LEN("Last-Modified"));
http_header_response_unset(r, HTTP_HEADER_CACHE_CONTROL,
CONST_STR_LEN("Cache-Control"));
http_header_response_unset(r, HTTP_HEADER_EXPIRES,
CONST_STR_LEN("Expires"));
}
#endif
r->resp_body_finished = 1;
}
default:
break;
}
}
void http_response_upgrade_read_body_unknown(request_st * const r) {
/* act as transparent proxy */
if (!(r->conf.stream_request_body & FDEVENT_STREAM_REQUEST))
r->conf.stream_request_body |=
(FDEVENT_STREAM_REQUEST_BUFMIN | FDEVENT_STREAM_REQUEST);
if (!(r->conf.stream_response_body & FDEVENT_STREAM_RESPONSE))
r->conf.stream_response_body |=
(FDEVENT_STREAM_RESPONSE_BUFMIN | FDEVENT_STREAM_RESPONSE);
r->conf.stream_request_body |= FDEVENT_STREAM_REQUEST_POLLIN;
r->reqbody_length = -2;
r->resp_body_scratchpad = -1;
r->keep_alive = 0;
}
__attribute_pure__
static int http_response_append_buffer_simple_accum(const request_st * const r, const off_t len) {
/*(check to accumulate small reads in buffer before flushing to temp file)*/
return
len < 32768 && r->write_queue.last && r->write_queue.last->file.is_temp;
}
static int http_response_append_buffer(request_st * const r, buffer * const mem, const int simple_accum) {
/* Note: this routine is separate from http_response_append_mem() to
* potentially avoid copying buffer by using http_chunk_append_buffer(). */
if (r->resp_decode_chunked)
return http_chunk_decode_append_buffer(r, mem);
if (r->resp_body_scratchpad > 0) {
off_t len = (off_t)buffer_clen(mem);
r->resp_body_scratchpad -= len;
if (r->resp_body_scratchpad > 0) {
if (simple_accum
&& http_response_append_buffer_simple_accum(r, len)) {
r->resp_body_scratchpad += len;
return 0; /*(accumulate small reads in buffer)*/
}
}
else { /* (r->resp_body_scratchpad <= 0) */
r->resp_body_finished = 1;
if (r->resp_body_scratchpad < 0) {
/*(silently truncate if data exceeds Content-Length)*/
len += r->resp_body_scratchpad;
r->resp_body_scratchpad = 0;
buffer_truncate(mem, (uint32_t)len);
}
}
}
else if (0 == r->resp_body_scratchpad) {
/*(silently truncate if data exceeds Content-Length)*/
buffer_clear(mem);
return 0;
}
else if (simple_accum
&& http_response_append_buffer_simple_accum(r, buffer_clen(mem))) {
return 0; /*(accumulate small reads in buffer)*/
}
return http_chunk_append_buffer(r, mem);
}
#ifdef HAVE_SPLICE
static int http_response_append_splice(request_st * const r, http_response_opts * const opts, buffer * const b, const int fd, unsigned int toread) {
/* check if worthwhile to splice() to avoid copying through userspace */
/*assert(opts->simple_accum);*//*(checked in caller)*/
if (r->resp_body_scratchpad >= toread
&& (toread > 32768
|| (toread >= 8192 /*(!http_response_append_buffer_simple_accum())*/
&& r->write_queue.last && r->write_queue.last->file.is_temp))) {
if (!buffer_is_blank(b)) {
/*(flush small reads previously accumulated in b)*/
int rc = http_response_append_buffer(r, b, 0); /*(0 to flush)*/
chunk_buffer_yield(b); /*(improve large buf reuse)*/
if (__builtin_expect( (0 != rc), 0)) return -1; /* error */
}
/*assert(opts->fdfmt == S_IFSOCK || opts->fdfmt == S_IFIFO);*/
ssize_t n = (opts->fdfmt == S_IFSOCK)
? chunkqueue_append_splice_sock_tempfile(
&r->write_queue, fd, toread, r->conf.errh)
: chunkqueue_append_splice_pipe_tempfile(
&r->write_queue, fd, toread, r->conf.errh);
if (__builtin_expect( (n >= 0), 1)) {
if (0 == (r->resp_body_scratchpad -= n))
r->resp_body_finished = 1;
return 1; /* success */
}
else if (n != -EINVAL)
return -1; /* error */
/*(fall through; target filesystem w/o splice() support)*/
}
return 0; /* not handled */
}
#endif
static int http_response_append_mem(request_st * const r, const char * const mem, size_t len) {
if (r->resp_decode_chunked)
return http_chunk_decode_append_mem(r, mem, len);
if (r->resp_body_scratchpad > 0) {
r->resp_body_scratchpad -= (off_t)len;
if (r->resp_body_scratchpad <= 0) {
r->resp_body_finished = 1;
if (r->resp_body_scratchpad < 0) {
/*(silently truncate if data exceeds Content-Length)*/
len = (size_t)(r->resp_body_scratchpad + (off_t)len);
r->resp_body_scratchpad = 0;
}
}
}
else if (0 == r->resp_body_scratchpad) {
/*(silently truncate if data exceeds Content-Length)*/
return 0;
}
return http_chunk_append_mem(r, mem, len);
}
static int http_response_process_headers(request_st * const restrict r, http_response_opts * const restrict opts, char * const restrict s, const unsigned short hoff[8192], const int is_nph) {
int i = 1;
if (is_nph) {
/* non-parsed headers ... we parse them anyway */
/* (accept HTTP/2.0 and HTTP/3.0 from naive non-proxy backends) */
/* (http_header_str_to_code() expects certain chars after code) */
if (s[12] == '\r' || s[12] == '\n') s[12] = '\0';/*(caller checked 12)*/
if ((s[5] == '1' || opts->backend != BACKEND_PROXY) && s[6] == '.'
&& (s[7] == '1' || s[7] == '0') && s[8] == ' ') {
/* after the space should be a status code for us */
int status = http_header_str_to_code(s+9);
if (status >= 100 && status < 1000) {
#ifdef __COVERITY__ /* Coverity false positive for tainted data */
status = 200;/* http_header_str_to_code() validates, untaints */
#endif
r->http_status = status;
opts->local_redir = 0; /*(disable; status was set)*/
i = 2;
} /* else we expected 3 digits and didn't get them */
}
if (0 == r->http_status) {
log_error(r->conf.errh, __FILE__, __LINE__,
"invalid HTTP status line: %s", s);
r->http_status = 502; /* Bad Gateway */
r->handler_module = NULL;
return 0;
}
}
else if (__builtin_expect( (opts->backend == BACKEND_PROXY), 0)) {
/* invalid response Status-Line from HTTP proxy */
r->http_status = 502; /* Bad Gateway */
r->handler_module = NULL;
return 0;
}
for (; i < hoff[0]; ++i) {
const char *k = s+hoff[i], *value;
char *end = s+hoff[i+1]-1; /*('\n')*/
/* parse the headers */
if (NULL == (value = memchr(k, ':', end - k))) {
/* we expect: "<key>: <value>\r\n" */
continue;
}
const uint32_t klen = (uint32_t)(value - k);
if (0 == klen) continue; /*(already ignored when writing response)*/
const enum http_header_e id = http_header_hkey_get(k, klen);
do { ++value; } while (*value == ' ' || *value == '\t'); /* skip LWS */
/* strip the \r?\n */
if (end > value && end[-1] == '\r') --end;
/*(XXX: not done; could remove trailing whitespace)*/
if (opts->authorizer && (0 == r->http_status || 200 == r->http_status)){
if (id == HTTP_HEADER_STATUS) {
end[0] = '\0';
int status = http_header_str_to_code(value);
if (status >= 100 && status < 1000) {
#ifdef __COVERITY__ /* Coverity false positive for tainted */
status = 200;/* http_header_str_to_code() validates */
#endif
r->http_status = status;
opts->local_redir = 0; /*(disable; status was set)*/
}
else {
r->http_status = 502; /* Bad Gateway */
break; /*(do not unset r->handler_module)*/
}
}
else if (id == HTTP_HEADER_OTHER && klen > 9 && (k[0] & 0xdf) == 'V'
&& buffer_eq_icase_ssn(k, CONST_STR_LEN("Variable-"))) {
http_header_env_append(r, k + 9, klen - 9, value, end - value);
}
continue;
}
switch (id) {
case HTTP_HEADER_STATUS:
if (opts->backend != BACKEND_PROXY) {
end[0] = '\0';
int status = http_header_str_to_code(value);
if (status >= 100 && status < 1000) {
#ifdef __COVERITY__ /* Coverity false positive for tainted */
status = 200;/* http_header_str_to_code() validates */
#endif
r->http_status = status;
opts->local_redir = 0; /*(disable; status was set)*/
}
else {
r->http_status = 502;
r->handler_module = NULL;
}
continue; /* do not send Status to client */
} /*(else pass w/o parse for BACKEND_PROXY)*/
break;
case HTTP_HEADER_UPGRADE:
/*(technically, should also verify Connection: upgrade)*/
/*(flag only for mod_proxy and mod_cgi (for now))*/
if (opts->backend != BACKEND_PROXY && opts->backend != BACKEND_CGI)
continue;
if (r->http_version >= HTTP_VERSION_2) continue;
break;
case HTTP_HEADER_CONNECTION:
if (opts->backend == BACKEND_PROXY) continue;
/*(simplistic attempt to honor backend request to close)*/
if (http_header_str_contains_token(value, end - value,
CONST_STR_LEN("close")))
r->keep_alive = 0;
if (r->http_version >= HTTP_VERSION_2) continue;
break;
case HTTP_HEADER_CONTENT_LENGTH:
if (*value == '+') ++value;
if (!r->resp_decode_chunked
&& !light_btst(r->resp_htags, HTTP_HEADER_CONTENT_LENGTH)) {
const char *err = end;
while (err > value && (err[-1] == ' ' || err[-1] == '\t')) --err;
if (err <= value) continue; /*(might error 502 Bad Gateway)*/
uint32_t vlen = (uint32_t)(err - value);
r->resp_body_scratchpad =
(off_t)li_restricted_strtoint64(value, vlen, &err);
if (err != value + vlen) {
/*(invalid Content-Length value from backend;
* read from backend until backend close, hope for the best)
*(might choose to treat this as 502 Bad Gateway) */
r->resp_body_scratchpad = -1;
}
}
else {
/* ignore Content-Length if Transfer-Encoding: chunked
* ignore subsequent (multiple) Content-Length
* (might choose to treat this as 502 Bad Gateway) */
continue;
}
break;
case HTTP_HEADER_TRANSFER_ENCODING:
if (light_btst(r->resp_htags, HTTP_HEADER_CONTENT_LENGTH)) {
/* ignore Content-Length if Transfer-Encoding: chunked
* (might choose to treat this as 502 Bad Gateway) */
r->resp_body_scratchpad = -1;
http_header_response_unset(r, HTTP_HEADER_CONTENT_LENGTH,
CONST_STR_LEN("Content-Length"));
}
/*(assumes "Transfer-Encoding: chunked"; does not verify)*/
r->resp_decode_chunked = 1;
r->gw_dechunk = calloc(1, sizeof(response_dechunk));
force_assert(r->gw_dechunk);
continue;
case HTTP_HEADER_HTTP2_SETTINGS:
/* RFC7540 3.2.1
* A server MUST NOT send this header field. */
/* (not bothering to remove HTTP2-Settings from Connection) */
continue;
case HTTP_HEADER_OTHER:
/* ignore invalid headers with whitespace between label and ':'
* (if less strict behavior is desired, check and correct above
* this switch() statement, but not for BACKEND_PROXY) */
if (k[klen-1] == ' ' || k[klen-1] == '\t')
continue;
break;
default:
break;
}
if (end - value)
http_header_response_insert(r, id, k, klen, value, end - value);
}
/* CGI/1.1 rev 03 - 7.2.1.2 */
/* (proxy requires Status-Line, so never true for proxy)*/
if (0 == r->http_status && light_btst(r->resp_htags, HTTP_HEADER_LOCATION)){
r->http_status = 302;
}
return 0;
}
static http_response_send_1xx_cb http_response_send_1xx_h1;
static http_response_send_1xx_cb http_response_send_1xx_h2;
void
http_response_send_1xx_cb_set (http_response_send_1xx_cb fn, int vers)
{
if (vers >= HTTP_VERSION_2)
http_response_send_1xx_h2 = fn;
else if (vers == HTTP_VERSION_1_1)
http_response_send_1xx_h1 = fn;
}
int
http_response_send_1xx (request_st * const r)
{
http_response_send_1xx_cb http_response_send_1xx_fn = NULL;
if (r->http_version >= HTTP_VERSION_2)
http_response_send_1xx_fn = http_response_send_1xx_h2;
else if (r->http_version == HTTP_VERSION_1_1)
http_response_send_1xx_fn = http_response_send_1xx_h1;
if (http_response_send_1xx_fn && !http_response_send_1xx_fn(r, r->con))
return 0; /* error occurred */
http_response_header_clear(r);
return 1; /* 1xx response handled */
}
__attribute_cold__
__attribute_noinline__
static int
http_response_check_1xx (request_st * const r, buffer * const restrict b, uint32_t hlen, uint32_t dlen)
{
/* pass through unset r->http_status (not 1xx) or 101 Switching Protocols */
if (0 == r->http_status || 101 == r->http_status)
return 0; /* pass through as-is; do not loop for addtl response hdrs */
/* discard 1xx response from b; already processed
* (but further response might follow in b, so preserve addtl data) */
if (dlen)
memmove(b->ptr, b->ptr+hlen, dlen);
buffer_truncate(b, dlen);
/* Note: while GW_AUTHORIZER mode is not expected to return 1xx, as a
* feature, 1xx responses from authorizer are passed back to client */
return http_response_send_1xx(r);
/* 0: error, 1: 1xx response handled; loop for next response headers */
}
__attribute_noinline__
handler_t http_response_parse_headers(request_st * const r, http_response_opts * const opts, buffer * const b) {
/**
* possible formats of response headers:
*
* proxy or NPH (non-parsed headers):
*
* HTTP/1.0 200 Ok\n
* Header: Value\n
* \n
*
* CGI:
*
* Header: Value\n
* Status: 200\n
* \n
*
* and different mixes of \n and \r\n combinations
*
* Some users also forget about CGI and just send a response
* and hope we handle it. No headers, no header-content separator
*/
const char *bstart;
uint32_t blen;
do {
uint32_t header_len, is_nph = 0;
unsigned short hoff[8192]; /* max num header lines + 3; 16k on stack */
hoff[0] = 1; /* number of lines */
hoff[1] = 0; /* base offset for all lines */
hoff[2] = 0; /* offset from base for 2nd line; init 0 to detect '\n' */
blen = buffer_clen(b);
header_len = http_header_parse_hoff(b->ptr, blen, hoff);
if ((header_len ? header_len : blen) > MAX_HTTP_RESPONSE_FIELD_SIZE) {
log_error(r->conf.errh, __FILE__, __LINE__,
"response headers too large for %s", r->uri.path.ptr);
r->http_status = 502; /* Bad Gateway */
r->handler_module = NULL;
return HANDLER_FINISHED;
}
if (hoff[2]) { /*(at least one newline found if offset is non-zero)*/
/*("HTTP/1.1 200 " is at least 13 chars + \r\n; 12 w/o final ' ')*/
is_nph = hoff[2] >= 12 && 0 == memcmp(b->ptr, "HTTP/", 5);
if (!is_nph) {
const char * colon = memchr(b->ptr, ':', hoff[2]-1);
if (__builtin_expect( (NULL == colon), 0)) {
if (hoff[2] <= 2 && (1 == hoff[2] || b->ptr[0] == '\r')) {
/* no HTTP headers */
}
else if (opts->backend == BACKEND_CGI) {
/* no HTTP headers, but body (special-case for CGI)*/
/* no colon found; does not appear to be HTTP headers */
if (0 != http_chunk_append_buffer(r, b)) {
return HANDLER_ERROR;
}
r->http_status = 200; /* OK */
r->resp_body_started = 1;
return HANDLER_GO_ON;
}
else {
/* invalid response headers */
r->http_status = 502; /* Bad Gateway */
r->handler_module = NULL;
return HANDLER_FINISHED;
}
}
}
} /* else no newline yet; partial header line?) */
if (0 == header_len) /* headers incomplete */
return HANDLER_GO_ON;
/* the body starts after the EOL */
bstart = b->ptr + header_len;
blen -= header_len;
if (0 != http_response_process_headers(r, opts, b->ptr, hoff, is_nph))
return HANDLER_ERROR;
} while (r->http_status < 200
&& http_response_check_1xx(r, b, bstart - b->ptr, blen));
r->resp_body_started = 1;
if (opts->authorizer
&& (r->http_status == 0 || r->http_status == 200)) {
return HANDLER_GO_ON;
}
if (NULL == r->handler_module) {
return HANDLER_FINISHED;
}
if (opts->local_redir && r->http_status >= 300 && r->http_status < 400
&& 0 == blen) {
/* (Might not have begun to receive body yet, but do skip local-redir
* if we already have started receiving a response body (blen > 0)) */
/*(light_btst(r->resp_htags, HTTP_HEADER_LOCATION))*/
handler_t rc = http_cgi_local_redir(r);
if (rc != HANDLER_GO_ON) return rc;
}
if (opts->xsendfile_allow) {
buffer *vb;
/* X-Sendfile2 is deprecated; historical for fastcgi */
if (opts->backend == BACKEND_FASTCGI
&& NULL != (vb = http_header_response_get(r, HTTP_HEADER_OTHER,
CONST_STR_LEN("X-Sendfile2")))) {
http_response_xsendfile2(r, vb, opts->xsendfile_docroot);
/* http_header_response_unset() shortcut for HTTP_HEADER_OTHER */
buffer_clear(vb); /*(do not send to client)*/
if (NULL == r->handler_module)
r->resp_body_started = 0;
return HANDLER_FINISHED;
} else if (NULL != (vb = http_header_response_get(r, HTTP_HEADER_OTHER,
CONST_STR_LEN("X-Sendfile")))
|| (opts->backend == BACKEND_FASTCGI /* X-LIGHTTPD-send-file is deprecated; historical for fastcgi */
&& NULL != (vb = http_header_response_get(r, HTTP_HEADER_OTHER,
CONST_STR_LEN("X-LIGHTTPD-send-file"))))) {
http_response_xsendfile(r, vb, opts->xsendfile_docroot);
/* http_header_response_unset() shortcut for HTTP_HEADER_OTHER */
buffer_clear(vb); /*(do not send to client)*/
if (NULL == r->handler_module)
r->resp_body_started = 0;
return HANDLER_FINISHED;
}
}
if (blen > 0) {
/* modules which set opts->parse() (e.g. mod_ajp13, mod_fastcgi) must
* not pass buffer with excess data to this routine (and do not do so
* due to framing of response headers separately from response body) */
int rc = http_response_append_mem(r, bstart, blen);
if (__builtin_expect( (0 != rc), 0))
return HANDLER_ERROR;
}
/* (callback for response headers complete) */
return (opts->headers) ? opts->headers(r, opts) : HANDLER_GO_ON;
}
handler_t http_response_read(request_st * const r, http_response_opts * const opts, buffer * const b, fdnode * const fdn) {
const int fd = fdn->fd;
ssize_t n;
size_t avail;
/*size_t total = 0;*/
do {
unsigned int toread = 0;
avail = buffer_string_space(b);
if (0 == fdevent_ioctl_fionread(fd, opts->fdfmt, (int *)&toread)) {
#ifdef HAVE_SPLICE
/* check if worthwhile to splice() to avoid copying to userspace */
if (opts->simple_accum) {
int rc = http_response_append_splice(r, opts, b, fd, toread);
if (rc) {
if (__builtin_expect( (rc > 0), 1))
break;
return HANDLER_ERROR;
} /*(fall through to handle traditionally)*/
}
#endif
if (avail < toread) {
uint32_t blen = buffer_clen(b);
if (toread + blen < 4096)
toread = 4095 - blen;
else if (toread > opts->max_per_read)
toread = opts->max_per_read;
/* reduce amount read for response headers to reduce extra data
* copying for initial data following response headers
* (see http_response_parse_headers())
* (This seems reasonable to do even if opts->parse is set)
* (default chunk buffer is 8k; typical response headers < 8k)
* (An alternative might be the opposite: read extra, e.g. 128k,
* if data available, in order to write to temp files sooner)*/
if (toread > 8192 && !r->resp_body_started) toread = 8192;
}
else if (0 == toread) {
#if 0
return (fdevent_fdnode_interest(fdn) & FDEVENT_IN)
? HANDLER_FINISHED /* read finished */
: HANDLER_GO_ON; /* optimistic read; data not ready */
#else
if (!(fdevent_fdnode_interest(fdn) & FDEVENT_IN)) {
if (!(r->conf.stream_response_body
& FDEVENT_STREAM_RESPONSE_POLLRDHUP))
return HANDLER_GO_ON;/*optimistic read; data not ready*/
}
if (0 == avail) /* let read() below indicate if EOF or EAGAIN */
toread = 1024;
#endif
}
}
else if (avail < 1024) {
toread = 4095 - avail;
}
if (r->conf.stream_response_body & FDEVENT_STREAM_RESPONSE_BUFMIN) {
off_t cqlen = chunkqueue_length(&r->write_queue);
if (cqlen + (off_t)toread > 65536 - 4096) {
if (!r->con->is_writable) {
/*(defer removal of FDEVENT_IN interest since
* connection_state_machine() might be able to send data
* immediately, unless !con->is_writable, where
* connection_state_machine() might not loop back to call
* mod_proxy_handle_subrequest())*/
fdevent_fdnode_event_clr(r->con->srv->ev, fdn, FDEVENT_IN);
}
if (cqlen >= 65536-1) {
if (buffer_is_blank(b))
chunk_buffer_yield(b); /*(improve large buf reuse)*/
return HANDLER_GO_ON;
}
toread = 65536 - 1 - (unsigned int)cqlen;
/* Note: heuristic is fuzzy in that it limits how much to read
* from backend based on how much is pending to write to client.
* Modules where data from backend is framed (e.g. FastCGI) may
* want to limit how much is buffered from backend while waiting
* for a complete data frame or data packet from backend. */
}
}
if (avail < toread) {
/*(add avail+toread to reduce allocations when ioctl EOPNOTSUPP)*/
avail = toread < opts->max_per_read && avail
? avail-1+toread
: toread;
avail = chunk_buffer_prepare_append(b, avail);
}
n = read(fd, b->ptr+buffer_clen(b), avail);
if (n < 0) {
switch (errno) {
case EAGAIN:
#ifdef EWOULDBLOCK
#if EWOULDBLOCK != EAGAIN
case EWOULDBLOCK:
#endif
#endif
case EINTR:
if (buffer_is_blank(b))
chunk_buffer_yield(b); /*(improve large buf reuse)*/
return HANDLER_GO_ON;
default:
log_perror(r->conf.errh, __FILE__, __LINE__,
"read() %d %d", r->con->fd, fd);
return HANDLER_ERROR;
}
}
buffer_commit(b, (size_t)n);
#ifdef __COVERITY__
/* Coverity Scan overlooks the effect of buffer_commit() */
b->ptr[buffer_clen(b)+n] = '\0';
#endif
if (NULL != opts->parse) {
handler_t rc = opts->parse(r, opts, b, (size_t)n);
if (rc != HANDLER_GO_ON) return rc;
} else if (0 == n) {
if (buffer_is_blank(b))
chunk_buffer_yield(b); /*(improve large buf reuse)*/
else if (opts->simple_accum) {
/*(flush small reads previously accumulated in b)*/
int rc = http_response_append_buffer(r, b, 0); /*(0 to flush)*/
chunk_buffer_yield(b); /*(improve large buf reuse)*/
if (__builtin_expect( (0 != rc), 0)) {
/* error writing to tempfile;
* truncate response or send 500 if nothing sent yet */
return HANDLER_ERROR;
}
}
/* note: no further data is sent to backend after read EOF on socket
* (not checking for half-closed TCP socket)
* (backend should read all data desired prior to closing socket,
* though might send app-level close data frame, if applicable) */
return HANDLER_FINISHED; /* read finished */
} else if (0 == r->resp_body_started) {
/* split header from body */
handler_t rc = http_response_parse_headers(r, opts, b);
if (rc != HANDLER_GO_ON) return rc;
/* accumulate response in b until headers completed (or error)*/
if (r->resp_body_started) {
buffer_clear(b);
/* enable simple accumulation of small reads in some situations
* no Content-Length (will read to EOF)
* Content-Length (will read until r->resp_body_scratchpad == 0)
* not chunked-encoding
* not bufmin streaming
* (no custom parse routine set for opts->parse()) */
if (!r->resp_decode_chunked /* && NULL == opts->parse */
&& !(r->conf.stream_response_body
& FDEVENT_STREAM_RESPONSE_BUFMIN))
opts->simple_accum = 1;
}
} else {
/* flush b (do not accumulate small reads) if streaming and might
* write to client since there is a chance that r->write_queue is
* fully written to client (no more temp files) and then we do not
* want to hold onto buffered data in b for an indeterminate time
* until next read of data from backend */
int simple_accum = opts->simple_accum
&& (!(r->conf.stream_response_body
& FDEVENT_STREAM_RESPONSE)
|| !r->con->is_writable);
int rc = http_response_append_buffer(r, b, simple_accum);
if (__builtin_expect( (0 != rc), 0)) {
/* error writing to tempfile;
* truncate response or send 500 if nothing sent yet */
return HANDLER_ERROR;
}
/*buffer_clear(b);*//*http_response_append_buffer() clears*/
/* small reads might accumulate in b; not necessarily cleared */
}
if (r->conf.stream_response_body & FDEVENT_STREAM_RESPONSE_BUFMIN) {
if (chunkqueue_length(&r->write_queue) > 65536 - 4096) {
/*(defer removal of FDEVENT_IN interest since
* connection_state_machine() might be able to send
* data immediately, unless !con->is_writable, where
* connection_state_machine() might not loop back to
* call the subrequest handler)*/
if (!r->con->is_writable)
fdevent_fdnode_event_clr(r->con->srv->ev, fdn, FDEVENT_IN);
break;
}
}
} while (!r->resp_body_started); /*(loop to read large response headers)*/
/*while (0);*//*(extra logic might benefit systems without FIONREAD)*/
/*while ((size_t)n == avail && (total += (size_t)n) < opts->max_per_read);*/
/* else emptied kernel read buffer or partial read or reached read limit */
if (buffer_is_blank(b)) chunk_buffer_yield(b); /*(improve large buf reuse)*/
return (!r->resp_body_finished ? HANDLER_GO_ON : HANDLER_FINISHED);
}