/*
* libwebsockets - small server side websockets and web server implementation
*
* Original code used in this source file:
*
* https://github.com/PerBothner/DomTerm.git @912add15f3d0aec
*
* ./lws-term/io.c
* ./lws-term/junzip.c
*
* Copyright (C) 2017 Per Bothner <per@bothner.com>
*
* MIT License
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* ( copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*
*
* lws rewrite:
*
* Copyright (C) 2017 Andy Green <andy@warmcat.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation:
* version 2.1 of the License.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301 USA
*/
#include "private-libwebsockets.h"
#include <zlib.h>
/*
* This code works with zip format containers which may have files compressed
* with gzip deflate (type 8) or store uncompressed (type 0).
*
* Linux zip produces such zipfiles by default, eg
*
* $ zip ../myzip.zip file1 file2 file3
*/
#define ZIP_COMPRESSION_METHOD_STORE 0
#define ZIP_COMPRESSION_METHOD_DEFLATE 8
typedef struct {
lws_filepos_t filename_start;
uint32_t crc32;
uint32_t comp_size;
uint32_t uncomp_size;
uint32_t offset;
uint32_t mod_time;
uint16_t filename_len;
uint16_t extra;
uint16_t method;
uint16_t file_com_len;
} lws_fops_zip_hdr_t;
typedef struct {
struct lws_fop_fd fop_fd; /* MUST BE FIRST logical fop_fd into
* file inside zip: fops_zip fops */
lws_fop_fd_t zip_fop_fd; /* logical fop fd on to zip file
* itself: using platform fops */
lws_fops_zip_hdr_t hdr;
z_stream inflate;
lws_filepos_t content_start;
lws_filepos_t exp_uncomp_pos;
union {
uint8_t trailer8[8];
uint32_t trailer32[2];
} u;
uint8_t rbuf[128]; /* decompression chunk size */
int entry_count;
unsigned int decompress:1; /* 0 = direct from file */
unsigned int add_gzip_container:1;
} *lws_fops_zip_t;
struct lws_plat_file_ops fops_zip;
#define fop_fd_to_priv(FD) ((lws_fops_zip_t)(FD))
static const uint8_t hd[] = { 31, 139, 8, 0, 0, 0, 0, 0, 0, 3 };
enum {
ZC_SIGNATURE = 0,
ZC_VERSION_MADE_BY = 4,
ZC_VERSION_NEEDED_TO_EXTRACT = 6,
ZC_GENERAL_PURPOSE_BIT_FLAG = 8,
ZC_COMPRESSION_METHOD = 10,
ZC_LAST_MOD_FILE_TIME = 12,
ZC_LAST_MOD_FILE_DATE = 14,
ZC_CRC32 = 16,
ZC_COMPRESSED_SIZE = 20,
ZC_UNCOMPRESSED_SIZE = 24,
ZC_FILE_NAME_LENGTH = 28,
ZC_EXTRA_FIELD_LENGTH = 30,
ZC_FILE_COMMENT_LENGTH = 32,
ZC_DISK_NUMBER_START = 34,
ZC_INTERNAL_FILE_ATTRIBUTES = 36,
ZC_EXTERNAL_FILE_ATTRIBUTES = 38,
ZC_REL_OFFSET_LOCAL_HEADER = 42,
ZC_DIRECTORY_LENGTH = 46,
ZE_SIGNATURE_OFFSET = 0,
ZE_DESK_NUMBER = 4,
ZE_CENTRAL_DIRECTORY_DISK_NUMBER = 6,
ZE_NUM_ENTRIES_THIS_DISK = 8,
ZE_NUM_ENTRIES = 10,
ZE_CENTRAL_DIRECTORY_SIZE = 12,
ZE_CENTRAL_DIR_OFFSET = 16,
ZE_ZIP_COMMENT_LENGTH = 20,
ZE_DIRECTORY_LENGTH = 22,
ZL_REL_OFFSET_CONTENT = 28,
ZL_HEADER_LENGTH = 30,
LWS_FZ_ERR_SEEK_END_RECORD = 1,
LWS_FZ_ERR_READ_END_RECORD,
LWS_FZ_ERR_END_RECORD_MAGIC,
LWS_FZ_ERR_END_RECORD_SANITY,
LWS_FZ_ERR_CENTRAL_SEEK,
LWS_FZ_ERR_CENTRAL_READ,
LWS_FZ_ERR_CENTRAL_SANITY,
LWS_FZ_ERR_NAME_TOO_LONG,
LWS_FZ_ERR_NAME_SEEK,
LWS_FZ_ERR_NAME_READ,
LWS_FZ_ERR_CONTENT_SANITY,
LWS_FZ_ERR_CONTENT_SEEK,
LWS_FZ_ERR_SCAN_SEEK,
LWS_FZ_ERR_NOT_FOUND,
LWS_FZ_ERR_ZLIB_INIT,
LWS_FZ_ERR_READ_CONTENT,
LWS_FZ_ERR_SEEK_COMPRESSED,
};
static uint16_t
get_u16(void *p)
{
const uint8_t *c = (const uint8_t *)p;
return (uint16_t)((c[0] | (c[1] << 8)));
}
static uint32_t
get_u32(void *p)
{
const uint8_t *c = (const uint8_t *)p;
return (uint32_t)((c[0] | (c[1] << 8) | (c[2] << 16) | (c[3] << 24)));
}
int
lws_fops_zip_scan(lws_fops_zip_t priv, const char *name, int len)
{
lws_filepos_t amount;
uint8_t buf[96];
int i;
if (lws_vfs_file_seek_end(priv->zip_fop_fd, -ZE_DIRECTORY_LENGTH) < 0)
return LWS_FZ_ERR_SEEK_END_RECORD;
if (lws_vfs_file_read(priv->zip_fop_fd, &amount, buf,
ZE_DIRECTORY_LENGTH))
return LWS_FZ_ERR_READ_END_RECORD;
if (amount != ZE_DIRECTORY_LENGTH)
return LWS_FZ_ERR_READ_END_RECORD;
/*
* We require the zip to have the last record right at the end
* Linux zip always does this if no zip comment.
*/
if (buf[0] != 'P' || buf[1] != 'K' || buf[2] != 5 || buf[3] != 6)
return LWS_FZ_ERR_END_RECORD_MAGIC;
i = get_u16(buf + ZE_NUM_ENTRIES);
if (get_u16(buf + ZE_DESK_NUMBER) ||
get_u16(buf + ZE_CENTRAL_DIRECTORY_DISK_NUMBER) ||
i != get_u16(buf + ZE_NUM_ENTRIES_THIS_DISK))
return LWS_FZ_ERR_END_RECORD_SANITY;
/* end record is OK... look for our file in the central dir */
if (lws_vfs_file_seek_set(priv->zip_fop_fd,
get_u32(buf + ZE_CENTRAL_DIR_OFFSET)) < 0)
return LWS_FZ_ERR_CENTRAL_SEEK;
while (i--) {
priv->content_start = lws_vfs_tell(priv->zip_fop_fd);
if (lws_vfs_file_read(priv->zip_fop_fd, &amount, buf,
ZC_DIRECTORY_LENGTH))
return LWS_FZ_ERR_CENTRAL_READ;
if (amount != ZC_DIRECTORY_LENGTH)
return LWS_FZ_ERR_CENTRAL_READ;
if (get_u32(buf + ZC_SIGNATURE) != 0x02014B50)
return LWS_FZ_ERR_CENTRAL_SANITY;
lwsl_debug("cstart 0x%lx\n", (unsigned long)priv->content_start);
priv->hdr.filename_len = get_u16(buf + ZC_FILE_NAME_LENGTH);
priv->hdr.extra = get_u16(buf + ZC_EXTRA_FIELD_LENGTH);
priv->hdr.filename_start = lws_vfs_tell(priv->zip_fop_fd);
priv->hdr.method = get_u16(buf + ZC_COMPRESSION_METHOD);
priv->hdr.crc32 = get_u32(buf + ZC_CRC32);
priv->hdr.comp_size = get_u32(buf + ZC_COMPRESSED_SIZE);
priv->hdr.uncomp_size = get_u32(buf + ZC_UNCOMPRESSED_SIZE);
priv->hdr.offset = get_u32(buf + ZC_REL_OFFSET_LOCAL_HEADER);
priv->hdr.mod_time = get_u32(buf + ZC_LAST_MOD_FILE_TIME);
priv->hdr.file_com_len = get_u16(buf + ZC_FILE_COMMENT_LENGTH);
if (priv->hdr.filename_len != len)
goto next;
if (len >= sizeof(buf) - 1)
return LWS_FZ_ERR_NAME_TOO_LONG;
if (priv->zip_fop_fd->fops->LWS_FOP_READ(priv->zip_fop_fd,
&amount, buf, len))
return LWS_FZ_ERR_NAME_READ;
if (amount != len)
return LWS_FZ_ERR_NAME_READ;
buf[len] = '\0';
lwsl_debug("check %s vs %s\n", buf, name);
if (strcmp((const char *)buf, name))
goto next;
/* we found a match */
if (lws_vfs_file_seek_set(priv->zip_fop_fd, priv->hdr.offset) < 0)
return LWS_FZ_ERR_NAME_SEEK;
if (priv->zip_fop_fd->fops->LWS_FOP_READ(priv->zip_fop_fd,
&amount, buf,
ZL_HEADER_LENGTH))
return LWS_FZ_ERR_NAME_READ;
if (amount != ZL_HEADER_LENGTH)
return LWS_FZ_ERR_NAME_READ;
priv->content_start = priv->hdr.offset +
ZL_HEADER_LENGTH +
priv->hdr.filename_len +
get_u16(buf + ZL_REL_OFFSET_CONTENT);
lwsl_debug("content supposed to start at 0x%lx\n",
(unsigned long)priv->content_start);
if (priv->content_start > priv->zip_fop_fd->len)
return LWS_FZ_ERR_CONTENT_SANITY;
if (lws_vfs_file_seek_set(priv->zip_fop_fd,
priv->content_start) < 0)
return LWS_FZ_ERR_CONTENT_SEEK;
/* we are aligned at the start of the content */
priv->exp_uncomp_pos = 0;
return 0;
next:
if (i && lws_vfs_file_seek_set(priv->zip_fop_fd,
priv->content_start +
ZC_DIRECTORY_LENGTH +
priv->hdr.filename_len +
priv->hdr.extra +
priv->hdr.file_com_len) < 0)
return LWS_FZ_ERR_SCAN_SEEK;
}
return LWS_FZ_ERR_NOT_FOUND;
}
static int
lws_fops_zip_reset_inflate(lws_fops_zip_t priv)
{
if (priv->decompress)
inflateEnd(&priv->inflate);
priv->inflate.zalloc = Z_NULL;
priv->inflate.zfree = Z_NULL;
priv->inflate.opaque = Z_NULL;
priv->inflate.avail_in = 0;
priv->inflate.next_in = Z_NULL;
if (inflateInit2(&priv->inflate, -MAX_WBITS) != Z_OK) {
lwsl_err("inflate init failed\n");
return LWS_FZ_ERR_ZLIB_INIT;
}
if (lws_vfs_file_seek_set(priv->zip_fop_fd, priv->content_start) < 0)
return LWS_FZ_ERR_CONTENT_SEEK;
priv->exp_uncomp_pos = 0;
return 0;
}
static lws_fop_fd_t
lws_fops_zip_open(const struct lws_plat_file_ops *fops, const char *vfs_path,
const char *vpath, lws_fop_flags_t *flags)
{
lws_fop_flags_t local_flags = 0;
lws_fops_zip_t priv;
char rp[192];
int m;
/*
* vpath points at the / after the fops signature in vfs_path, eg
* with a vfs_path "/var/www/docs/manual.zip/index.html", vpath
* will come pointing at "/index.html"
*/
priv = lws_zalloc(sizeof(*priv), "fops_zip priv");
if (!priv)
return NULL;
priv->fop_fd.fops = &fops_zip;
m = sizeof(rp) - 1;
if ((vpath - vfs_path - 1) < m)
m = vpath - vfs_path - 1;
strncpy(rp, vfs_path, m);
rp[m] = '\0';
/* open the zip file itself using the incoming fops, not fops_zip */
priv->zip_fop_fd = fops->LWS_FOP_OPEN(fops, rp, NULL, &local_flags);
if (!priv->zip_fop_fd) {
lwsl_err("unable to open zip %s\n", rp);
goto bail1;
}
if (*vpath == '/')
vpath++;
m = lws_fops_zip_scan(priv, vpath, strlen(vpath));
if (m) {
lwsl_err("unable to find record matching '%s' %d\n", vpath, m);
goto bail2;
}
/* the directory metadata tells us modification time, so pass it on */
priv->fop_fd.mod_time = priv->hdr.mod_time;
*flags |= LWS_FOP_FLAG_MOD_TIME_VALID | LWS_FOP_FLAG_VIRTUAL;
priv->fop_fd.flags = *flags;
/* The zip fop_fd is left pointing at the start of the content.
*
* 1) Content could be uncompressed (STORE), and we can always serve
* that directly
*
* 2) Content could be compressed (GZIP), and the client can handle
* receiving GZIP... we can wrap it in a GZIP header and trailer
* and serve the content part directly. The flag indicating we
* are providing GZIP directly is set so lws will send the right
* headers.
*
* 3) Content could be compressed (GZIP) but the client can't handle
* receiving GZIP... we can decompress it and serve as it is
* inflated piecemeal.
*
* 4) Content may be compressed some unknown way... fail
*
*/
if (priv->hdr.method == ZIP_COMPRESSION_METHOD_STORE) {
/*
* it is stored uncompressed, leave it indicated as
* uncompressed, and just serve it from inside the
* zip with no gzip container;
*/
lwsl_info("direct zip serving (stored)\n");
priv->fop_fd.len = priv->hdr.uncomp_size;
return &priv->fop_fd;
}
if ((*flags & LWS_FOP_FLAG_COMPR_ACCEPTABLE_GZIP) &&
priv->hdr.method == ZIP_COMPRESSION_METHOD_DEFLATE) {
/*
* We can serve the gzipped file contents directly as gzip
* from inside the zip container; client says it is OK.
*
* To convert to standalone gzip, we have to add a 10-byte
* constant header and a variable 8-byte trailer around the
* content.
*
* The 8-byte trailer is prepared now and held in the priv.
*/
lwsl_info("direct zip serving (gzipped)\n");
priv->fop_fd.len = sizeof(hd) + priv->hdr.comp_size +
sizeof(priv->u);
if (lws_is_be()) {
uint8_t *p = priv->u.trailer8;
*p++ = (uint8_t)priv->hdr.crc32;
*p++ = (uint8_t)(priv->hdr.crc32 >> 8);
*p++ = (uint8_t)(priv->hdr.crc32 >> 16);
*p++ = (uint8_t)(priv->hdr.crc32 >> 24);
*p++ = (uint8_t)priv->hdr.uncomp_size;
*p++ = (uint8_t)(priv->hdr.uncomp_size >> 8);
*p++ = (uint8_t)(priv->hdr.uncomp_size >> 16);
*p = (uint8_t)(priv->hdr.uncomp_size >> 24);
} else {
priv->u.trailer32[0] = priv->hdr.crc32;
priv->u.trailer32[1] = priv->hdr.uncomp_size;
}
*flags |= LWS_FOP_FLAG_COMPR_IS_GZIP;
priv->fop_fd.flags = *flags;
priv->add_gzip_container = 1;
return &priv->fop_fd;
}
if (priv->hdr.method == ZIP_COMPRESSION_METHOD_DEFLATE) {
/* we must decompress it to serve it */
lwsl_info("decompressed zip serving\n");
priv->fop_fd.len = priv->hdr.uncomp_size;
if (lws_fops_zip_reset_inflate(priv)) {
lwsl_err("inflate init failed\n");
goto bail2;
}
priv->decompress = 1;
return &priv->fop_fd;
}
/* we can't handle it ... */
lwsl_err("zipped file %s compressed in unknown way (%d)\n", vfs_path,
priv->hdr.method);
bail2:
lws_vfs_file_close(&priv->zip_fop_fd);
bail1:
free(priv);
return NULL;
}
/* ie, we are closing the fop_fd for the file inside the gzip */
static int
lws_fops_zip_close(lws_fop_fd_t *fd)
{
lws_fops_zip_t priv = fop_fd_to_priv(*fd);
if (priv->decompress)
inflateEnd(&priv->inflate);
lws_vfs_file_close(&priv->zip_fop_fd); /* close the gzip fop_fd */
free(priv);
*fd = NULL;
return 0;
}
static lws_fileofs_t
lws_fops_zip_seek_cur(lws_fop_fd_t fd, lws_fileofs_t offset_from_cur_pos)
{
fd->pos += offset_from_cur_pos;
return fd->pos;
}
static int
lws_fops_zip_read(lws_fop_fd_t fd, lws_filepos_t *amount, uint8_t *buf,
lws_filepos_t len)
{
lws_fops_zip_t priv = fop_fd_to_priv(fd);
lws_filepos_t ramount, rlen, cur = lws_vfs_tell(fd);
int ret;
if (priv->decompress) {
if (priv->exp_uncomp_pos != fd->pos) {
/*
* there has been a seek in the uncompressed fop_fd
* we have to restart the decompression and loop eating
* the decompressed data up to the seek point
*/
lwsl_info("seek in decompressed\n");
lws_fops_zip_reset_inflate(priv);
while (priv->exp_uncomp_pos != fd->pos) {
rlen = len;
if (rlen > fd->pos - priv->exp_uncomp_pos)
rlen = fd->pos - priv->exp_uncomp_pos;
if (lws_fops_zip_read(fd, amount, buf, rlen))
return LWS_FZ_ERR_SEEK_COMPRESSED;
}
*amount = 0;
}
priv->inflate.avail_out = (unsigned int)len;
priv->inflate.next_out = buf;
spin:
if (!priv->inflate.avail_in) {
rlen = sizeof(priv->rbuf);
if (rlen > priv->hdr.comp_size -
(cur - priv->content_start))
rlen = priv->hdr.comp_size -
(priv->hdr.comp_size -
priv->content_start);
if (priv->zip_fop_fd->fops->LWS_FOP_READ(
priv->zip_fop_fd, &ramount, priv->rbuf,
rlen))
return LWS_FZ_ERR_READ_CONTENT;
cur += ramount;
priv->inflate.avail_in = (unsigned int)ramount;
priv->inflate.next_in = priv->rbuf;
}
ret = inflate(&priv->inflate, Z_NO_FLUSH);
if (ret == Z_STREAM_ERROR)
return ret;
switch (ret) {
case Z_NEED_DICT:
ret = Z_DATA_ERROR;
/* and fall through */
case Z_DATA_ERROR:
case Z_MEM_ERROR:
return ret;
}
if (!priv->inflate.avail_in && priv->inflate.avail_out &&
cur != priv->content_start + priv->hdr.comp_size)
goto spin;
*amount = len - priv->inflate.avail_out;
priv->exp_uncomp_pos += *amount;
fd->pos += *amount;
return 0;
}
if (priv->add_gzip_container) {
lwsl_info("%s: gzip + container\n", __func__);
*amount = 0;
/* place the canned header at the start */
if (len && fd->pos < sizeof(hd)) {
rlen = sizeof(hd) - fd->pos;
if (rlen > len)
rlen = len;
/* provide stuff from canned header */
memcpy(buf, hd + fd->pos, (size_t)rlen);
fd->pos += rlen;
buf += rlen;
len -= rlen;
*amount += rlen;
}
/* serve gzipped data direct from zipfile */
if (len && fd->pos >= sizeof(hd) &&
fd->pos < priv->hdr.comp_size + sizeof(hd)) {
rlen = priv->hdr.comp_size - (priv->zip_fop_fd->pos -
priv->content_start);
if (rlen > len)
rlen = len;
if (rlen &&
priv->zip_fop_fd->pos < (priv->hdr.comp_size +
priv->content_start)) {
if (lws_vfs_file_read(priv->zip_fop_fd,
&ramount, buf, rlen))
return LWS_FZ_ERR_READ_CONTENT;
*amount += ramount;
fd->pos += ramount; // virtual pos
buf += ramount;
len -= ramount;
}
}
/* place the prepared trailer at the end */
if (len && fd->pos >= priv->hdr.comp_size + sizeof(hd) &&
fd->pos < priv->hdr.comp_size + sizeof(hd) +
sizeof(priv->u)) {
cur = fd->pos - priv->hdr.comp_size - sizeof(hd);
rlen = sizeof(priv->u) - cur;
if (rlen > len)
rlen = len;
memcpy(buf, priv->u.trailer8 + cur, (size_t)rlen);
*amount += rlen;
fd->pos += rlen;
}
return 0;
}
lwsl_info("%s: store\n", __func__);
if (len > priv->hdr.uncomp_size - (cur - priv->content_start))
len = priv->hdr.comp_size - (priv->hdr.comp_size -
priv->content_start);
if (priv->zip_fop_fd->fops->LWS_FOP_READ(priv->zip_fop_fd,
amount, buf, len))
return LWS_FZ_ERR_READ_CONTENT;
return 0;
}
struct lws_plat_file_ops fops_zip = {
lws_fops_zip_open,
lws_fops_zip_close,
lws_fops_zip_seek_cur,
lws_fops_zip_read,
NULL,
{ { ".zip/", 5 }, { ".jar/", 5 }, { ".war/", 5 } },
NULL,
};