lighttpd 1.4.x https://www.lighttpd.net/
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
 

476 lines
17 KiB

/*
* http_chunk - append response to chunkqueue, possibly in "chunked" encoding
*
* Fully-rewritten from original
* Copyright(c) 2019 Glenn Strauss gstrauss()gluelogic.com All rights reserved
* License: BSD 3-clause (same as lighttpd)
*/
#include "first.h"
#include "http_chunk.h"
#include "base.h"
#include "chunk.h"
#include "stat_cache.h"
#include "fdevent.h"
#include "log.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
static void http_chunk_len_append(chunkqueue * const cq, uintmax_t len) {
char buf[24]; /* 64-bit (8 bytes) is 16 hex chars (+2 \r\n, +1 \0 = 19) */
#if 0
buffer b = { buf, 0, sizeof(buf) };
buffer_append_uint_hex(&b, len);
buffer_append_string_len(&b, CONST_STR_LEN("\r\n"));
chunkqueue_append_mem(cq, b.ptr, b.used-1);
#else
int i = (int)(sizeof(buf));
buf[--i] = '\n';
buf[--i] = '\r';
do { buf[--i] = "0123456789abcdef"[len & 0x0F]; } while (len >>= 4);
chunkqueue_append_mem(cq, buf+i, sizeof(buf)-i);
#endif
}
static int http_chunk_len_append_tempfile(chunkqueue * const cq, uintmax_t len, log_error_st * const errh) {
char buf[24]; /* 64-bit (8 bytes) is 16 hex chars (+2 \r\n, +1 \0 = 19) */
#if 0
buffer b = { buf, 0, sizeof(buf) };
buffer_append_uint_hex(&b, len);
buffer_append_string_len(&b, CONST_STR_LEN("\r\n"));
return chunkqueue_append_mem_to_tempfile(cq, b.ptr, b.used-1, errh);
#else
int i = (int)(sizeof(buf));
buf[--i] = '\n';
buf[--i] = '\r';
do { buf[--i] = "0123456789abcdef"[len & 0x0F]; } while (len >>= 4);
return chunkqueue_append_mem_to_tempfile(cq, buf+i, sizeof(buf)-i, errh);
#endif
}
static int http_chunk_append_file_open_fstat(const request_st * const r, const buffer * const fn, struct stat * const st) {
return
(r->conf.follow_symlink
|| !stat_cache_path_contains_symlink(fn, r->conf.errh))
? stat_cache_open_rdonly_fstat(fn, st, r->conf.follow_symlink)
: -1;
}
static int http_chunk_append_read_fd_range(request_st * const r, const buffer * const fn, const int fd, off_t offset, off_t len) {
/* note: this routine should not be used for range requests
* unless the total size of ranges requested is small */
/* note: future: could read into existing MEM_CHUNK in cq->last if
* there is sufficient space, but would need to adjust for existing
* offset in for cq->bytes_in in chunkqueue_append_buffer_commit() */
UNUSED(fn);
chunkqueue * const cq = r->write_queue;
if (r->resp_send_chunked)
http_chunk_len_append(cq, (uintmax_t)len);
if (0 != offset && -1 == lseek(fd, offset, SEEK_SET)) return -1;
buffer * const b = chunkqueue_append_buffer_open_sz(cq, len+2);
ssize_t rd;
offset = 0;
do {
rd = read(fd, b->ptr+offset, len-offset);
} while (rd > 0 ? (offset += rd, len -= rd) : errno == EINTR);
buffer_commit(b, offset);
if (r->resp_send_chunked)
buffer_append_string_len(b, CONST_STR_LEN("\r\n"));
chunkqueue_append_buffer_commit(cq);
return (rd >= 0) ? 0 : -1;
}
static void http_chunk_append_file_fd_range(request_st * const r, const buffer * const fn, const int fd, const off_t offset, const off_t len) {
chunkqueue * const cq = r->write_queue;
if (r->resp_send_chunked)
http_chunk_len_append(cq, (uintmax_t)len);
chunkqueue_append_file_fd(cq, fn, fd, offset, len);
if (r->resp_send_chunked)
chunkqueue_append_mem(cq, CONST_STR_LEN("\r\n"));
}
int http_chunk_append_file_range(request_st * const r, const buffer * const fn, const off_t offset, off_t len) {
struct stat st;
const int fd = http_chunk_append_file_open_fstat(r, fn, &st);
if (fd < 0) return -1;
if (-1 == len) {
if (offset >= st.st_size) {
close(fd);
return (offset == st.st_size) ? 0 : -1;
}
len = st.st_size - offset;
}
else if (st.st_size - offset < len) {
close(fd);
return -1;
}
http_chunk_append_file_fd_range(r, fn, fd, offset, len);
return 0;
}
int http_chunk_append_file(request_st * const r, const buffer * const fn) {
struct stat st;
const int fd = http_chunk_append_file_open_fstat(r, fn, &st);
if (fd < 0) return -1;
http_chunk_append_file_fd(r, fn, fd, st.st_size);
return 0;
}
int http_chunk_append_file_fd(request_st * const r, const buffer * const fn, const int fd, const off_t sz) {
if (sz > 32768 || !r->resp_send_chunked) {
http_chunk_append_file_fd_range(r, fn, fd, 0, sz);
return 0;
}
/*(read small files into memory)*/
int rc = (0 != sz) ? http_chunk_append_read_fd_range(r,fn,fd,0,sz) : 0;
close(fd);
return rc;
}
static int http_chunk_append_to_tempfile(request_st * const r, const char * const mem, const size_t len) {
chunkqueue * const cq = r->write_queue;
log_error_st * const errh = r->conf.errh;
if (r->resp_send_chunked
&& 0 != http_chunk_len_append_tempfile(cq, len, errh))
return -1;
if (0 != chunkqueue_append_mem_to_tempfile(cq, mem, len, errh))
return -1;
if (r->resp_send_chunked
&& 0 !=
chunkqueue_append_mem_to_tempfile(cq, CONST_STR_LEN("\r\n"), errh))
return -1;
return 0;
}
static int http_chunk_append_cq_to_tempfile(request_st * const r, chunkqueue * const src, const size_t len) {
chunkqueue * const cq = r->write_queue;
log_error_st * const errh = r->conf.errh;
if (r->resp_send_chunked
&& 0 != http_chunk_len_append_tempfile(cq, len, errh))
return -1;
if (0 != chunkqueue_steal_with_tempfiles(cq, src, len, errh))
return -1;
if (r->resp_send_chunked
&& 0 !=
chunkqueue_append_mem_to_tempfile(cq, CONST_STR_LEN("\r\n"), errh))
return -1;
return 0;
}
__attribute_pure__
static int http_chunk_uses_tempfile(const request_st * const r, const chunkqueue * const cq, const size_t len) {
/* current usage does not append_mem or append_buffer after appending
* file, so not checking if users of this interface have appended large
* (references to) files to chunkqueue, which would not be in memory
* (but included in calculation for whether or not to use temp file) */
/*(allow slightly larger mem use if FDEVENT_STREAM_RESPONSE_BUFMIN
* to reduce creation of temp files when backend producer will be
* blocked until more data is sent to network to client)*/
const chunk * const c = cq->last;
return
((c && c->type == FILE_CHUNK && c->file.is_temp)
|| chunkqueue_length(cq) + len
> ((r->conf.stream_response_body & FDEVENT_STREAM_RESPONSE_BUFMIN)
? 128*1024
: 64*1024));
}
int http_chunk_append_buffer(request_st * const r, buffer * const mem) {
size_t len = buffer_string_length(mem);
if (0 == len) return 0;
chunkqueue * const cq = r->write_queue;
if (http_chunk_uses_tempfile(r, cq, len))
return http_chunk_append_to_tempfile(r, mem->ptr, len);
if (r->resp_send_chunked)
http_chunk_len_append(cq, len);
/*(chunkqueue_append_buffer() might steal buffer contents)*/
chunkqueue_append_buffer(cq, mem);
if (r->resp_send_chunked)
chunkqueue_append_mem(cq, CONST_STR_LEN("\r\n"));
return 0;
}
int http_chunk_append_mem(request_st * const r, const char * const mem, const size_t len) {
if (0 == len) return 0;
force_assert(NULL != mem);
chunkqueue * const cq = r->write_queue;
if (http_chunk_uses_tempfile(r, cq, len))
return http_chunk_append_to_tempfile(r, mem, len);
if (r->resp_send_chunked)
http_chunk_len_append(cq, len);
chunkqueue_append_mem(cq, mem, len);
if (r->resp_send_chunked)
chunkqueue_append_mem(cq, CONST_STR_LEN("\r\n"));
return 0;
}
int http_chunk_transfer_cqlen(request_st * const r, chunkqueue * const src, const size_t len) {
if (0 == len) return 0;
chunkqueue * const cq = r->write_queue;
if (http_chunk_uses_tempfile(r, cq, len))
return http_chunk_append_cq_to_tempfile(r, src, len);
if (r->resp_send_chunked)
http_chunk_len_append(cq, len);
chunkqueue_steal(cq, src, len);
if (r->resp_send_chunked)
chunkqueue_append_mem(cq, CONST_STR_LEN("\r\n"));
return 0;
}
void http_chunk_close(request_st * const r) {
if (!r->resp_send_chunked) return;
if (r->gw_dechunk && !buffer_string_is_empty(&r->gw_dechunk->b)) {
/* XXX: trailers passed through; no sanity check currently done */
chunkqueue_append_buffer(r->write_queue, &r->gw_dechunk->b);
if (!r->gw_dechunk->done)
r->keep_alive = 0;
}
else
chunkqueue_append_mem(r->write_queue, CONST_STR_LEN("0\r\n\r\n"));
}
static int
http_chunk_decode_append_data (request_st * const r, const char *mem, off_t len)
{
/*(silently discard data, if any, after final \r\n)*/
if (r->gw_dechunk->done) return 0;
buffer * const h = &r->gw_dechunk->b;
off_t te_chunked = r->gw_dechunk->gw_chunked;
while (len) {
if (0 == te_chunked) {
const char *p = strchr(mem, '\n');
/*(likely better ways to handle chunked header crossing chunkqueue
* chunks, but this situation is not expected to occur frequently)*/
if (NULL == p) { /* incomplete HTTP chunked header line */
uint32_t hlen = buffer_string_length(h);
if ((off_t)(1024 - hlen) < len) {
log_error(r->conf.errh, __FILE__, __LINE__,
"chunked header line too long");
return -1;
}
buffer_append_string_len(h, mem, len);
break;
}
off_t hsz = ++p - mem;
unsigned char *s = (unsigned char *)mem;
if (!buffer_string_is_empty(h)) {
uint32_t hlen = buffer_string_length(h);
if (NULL == memchr(h->ptr, '\n', hlen)) {
if ((off_t)(1024 - hlen) < hsz) {
log_error(r->conf.errh, __FILE__, __LINE__,
"chunked header line too long");
return -1;
}
buffer_append_string_len(h, mem, hsz);
}
s = (unsigned char *)h->ptr;
}
for (unsigned char u; (u=(unsigned char)hex2int(*s))!=0xFF; ++s) {
if (te_chunked > (off_t)(1uLL<<(8*sizeof(off_t)-5))-1) {
log_error(r->conf.errh, __FILE__, __LINE__,
"chunked data size too large");
return -1;
}
te_chunked <<= 4;
te_chunked |= u;
}
if ((char *)s == mem || (char *)s == h->ptr) return -1; /*(no hex)*/
while (*s == ' ' || *s == '\t') ++s;
if (*s != '\r' && *s != ';') { /*(not strictly checking \r\n)*/
log_error(r->conf.errh, __FILE__, __LINE__,
"chunked header invalid chars");
return -1;
}
if (0 == te_chunked) {
/* do not consume final chunked header until
* (optional) trailers received along with
* request-ending blank line "\r\n" */
if (len - hsz == 2 && p[0] == '\r' && p[1] == '\n') {
/* common case with no trailers; final \r\n received */
/*(silently discard data, if any, after final \r\n)*/
#if 0 /*(avoid allocation for common case; users must check)*/
if (buffer_is_empty(h))
buffer_copy_string_len(h, CONST_STR_LEN("0\r\n\r\n"));
#else
buffer_clear(h);
#endif
r->gw_dechunk->done = r->http_status;
break;
}
/* accumulate trailers and check for end of trailers */
/* XXX: reuse r->conf.max_request_field_size
* or have separate limit? */
uint32_t hlen = buffer_string_length(h);
if ((off_t)(r->conf.max_request_field_size - hlen) < hsz) {
/* truncate excessively long trailers */
r->gw_dechunk->done = r->http_status;
hsz = (off_t)(r->conf.max_request_field_size - hlen);
buffer_append_string_len(h, mem, hsz);
p = strrchr(h->ptr, '\n');
if (NULL != p)
buffer_string_set_length(h, p + 1 - h->ptr);
else { /*(should not happen)*/
buffer_clear(h);
buffer_append_string_len(h, CONST_STR_LEN("0\r\n"));
}
buffer_append_string_len(h, CONST_STR_LEN("\r\n"));
break;
}
buffer_append_string_len(h, mem, hsz);
hlen += (uint32_t)hsz; /* uint32_t fits in (buffer *) */
if (hlen < 4) break;
p = h->ptr + hlen - 4;
if (p[0]=='\r'&&p[1]=='\n'&&p[2]=='\r'&&p[3]=='\n')
r->gw_dechunk->done = r->http_status;
else if ((p = strstr(h->ptr, "\r\n\r\n"))) {
r->gw_dechunk->done = r->http_status;
/*(silently discard data, if any, after final \r\n)*/
buffer_string_set_length(h, (uint32_t)(p+4-h->ptr));
}
break;
}
mem += hsz;
len -= hsz;
if (te_chunked > (off_t)(1uLL<<(8*sizeof(off_t)-5))-1-2) {
log_error(r->conf.errh, __FILE__, __LINE__,
"chunked data size too large");
return -1;
}
te_chunked += 2; /*(for trailing "\r\n" after chunked data)*/
}
if (te_chunked >= 2) {
off_t clen = te_chunked - 2;
if (clen > len) clen = len;
if (0 != http_chunk_append_mem(r, mem, clen))
return -1;
mem += clen;
len -= clen;
te_chunked -= clen;
if (te_chunked == 2) {
if (len >= 2) {
if (mem[0] != '\r' || mem[1] != '\n') return -1;
mem += 2;
len -= 2;
te_chunked = 0;
}
else if (len == 1 && mem[0] != '\r') return -1;
}
}
else if (1 == te_chunked) {
/* finish reading chunk block "\r\n" */
if (mem[0] != '\n') return -1;
++mem;
--len;
te_chunked = 0;
}
}
r->gw_dechunk->gw_chunked = te_chunked;
return 0;
}
int http_chunk_decode_append_buffer(request_st * const r, buffer * const mem)
{
/*(called by funcs receiving data from backends, which might be chunked)*/
/*(separate from http_chunk_append_buffer() called by numerous others)*/
if (!r->resp_decode_chunked)
return http_chunk_append_buffer(r, mem);
/* no need to decode chunked to immediately re-encode chunked,
* though would be more robust to still validate chunk lengths sent
* (or else we might wait for keep-alive while client waits for final chunk)
* Before finishing response/stream, we *are not* checking if we got final
* chunk of chunked encoding from backend. If we were, we could consider
* closing HTTP/1.0 and HTTP/1.1 connections (no keep-alive), and in HTTP/2
* we could consider sending RST_STREAM error. http_chunk_close() would
* only handle case of streaming chunked to client */
if (r->resp_send_chunked) {
r->resp_send_chunked = 0;
int rc = http_chunk_append_buffer(r, mem); /* might append to tmpfile */
r->resp_send_chunked = 1;
return rc;
}
/* might avoid copy by transferring buffer if buffer is all data that is
* part of large chunked block, but choosing to *not* expand that out here*/
return http_chunk_decode_append_data(r, CONST_BUF_LEN(mem));
}
int http_chunk_decode_append_mem(request_st * const r, const char * const mem, const size_t len)
{
/*(called by funcs receiving data from backends, which might be chunked)*/
/*(separate from http_chunk_append_mem() called by numerous others)*/
if (!r->resp_decode_chunked)
return http_chunk_append_mem(r, mem, len);
/* no need to decode chunked to immediately re-encode chunked,
* though would be more robust to still validate chunk lengths sent
* (or else we might wait for keep-alive while client waits for final chunk)
* Before finishing response/stream, we *are not* checking if we got final
* chunk of chunked encoding from backend. If we were, we could consider
* closing HTTP/1.0 and HTTP/1.1 connections (no keep-alive), and in HTTP/2
* we could consider sending RST_STREAM error. http_chunk_close() would
* only handle case of streaming chunked to client */
if (r->resp_send_chunked) {
r->resp_send_chunked = 0;
int rc = http_chunk_append_mem(r, mem, len); /*might append to tmpfile*/
r->resp_send_chunked = 1;
return rc;
}
return http_chunk_decode_append_data(r, mem, (off_t)len);
}