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clamav/libclamav/xar.c
Valerie Snyder 31dcec1e42
libclamav: Add engine option to toggle temp directory recursion 
Temp directory recursion in ClamAV is when each layer of a scan gets its
own temp directory in the parent layer's temp directory.

In addition to temp directory recursion, ClamAV has been creating a new
subdirectory for each file scan as a risk-adverse method to ensure
no temporary file leaks fill up the disk.
Creating a directory is relatively slow on Windows in particular if
scanning a lot of very small files.

This commit:

1. Separates the temp directory recursion feature from the leave-temps
   feature so that libclamav can leave temp files without making
   subdirectories for each file scanned.

2. Makes it so that when temp directory recursion is off, libclamav
   will just use the configure temp directory for all files.

The new option to enable temp directory recursion is for libclamav-only
at this time. It is off by default, and you can enable it like this:

```c
cl_engine_set_num(engine, CL_ENGINE_TMPDIR_RECURSION, 1);
```

For the `clamscan` and `clamd` programs, temp directory recursion will
be enabled when `--leave-temps` / `LeaveTemporaryFiles` is enabled.

The difference is that when disabled, it will return to using the
configured temp directory without making a subdirectory for each file
scanned, so as to improve scan performance for small files, mostly on
Windows.

Under the hood, this commit also:

1. Cleans up how we keep track of tmpdirs for each layer.
   The goal here is to align how we keep track of layer-specific stuff
   using the scan_layer structure.

2. Cleans up how we record metadata JSON for embedded files.
   Note: Embedded files being different from Contained files, as they
         are extracted not with a parser, but by finding them with
         file type magic signatures.

CLAM-1583
2025-08-14 22:38:58 -04:00

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/*
* Copyright (C) 2013-2025 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
* Copyright (C) 2013 Sourcefire, Inc.
*
* Authors: Steven Morgan <smorgan@sourcefire.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301, USA.
*/
#if HAVE_CONFIG_H
#include "clamav-config.h"
#endif
#include <errno.h>
#include "xar.h"
#include "fmap.h"
#include <libxml/xmlreader.h>
#include "clamav.h"
#include "str.h"
#include "scanners.h"
#include "inflate64.h"
#include "lzma_iface.h"
/*
xar_cleanup_temp_file - cleanup after cli_gentempfd
parameters:
ctx - cli_ctx context pointer
fd - fd to close
tmpname - name of file to unlink, address of storage to free
returns - CL_SUCCESS or CL_EUNLINK
*/
static int xar_cleanup_temp_file(cli_ctx *ctx, int fd, char *tmpname)
{
int rc = CL_SUCCESS;
if (fd > -1)
close(fd);
if (tmpname != NULL) {
if (!ctx->engine->keeptmp) {
if (cli_unlink(tmpname)) {
cli_dbgmsg("cli_scanxar: error unlinking tmpfile %s\n", tmpname);
rc = CL_EUNLINK;
}
}
free(tmpname);
}
return rc;
}
/*
xar_get_numeric_from_xml_element - extract xml element value as numeric
parameters:
reader - xmlTextReaderPtr
value - pointer to long to contain the returned value
returns - CL_SUCCESS or CL_EFORMAT
*/
static int xar_get_numeric_from_xml_element(xmlTextReaderPtr reader, size_t *value)
{
const xmlChar *numstr;
if (xmlTextReaderRead(reader) == 1 && xmlTextReaderNodeType(reader) == XML_READER_TYPE_TEXT) {
numstr = xmlTextReaderConstValue(reader);
if (numstr) {
long numval;
char *endptr = NULL;
errno = 0;
numval = strtol((const char *)numstr, &endptr, 10);
if ((((numval == LONG_MAX) || (numval == LONG_MIN)) && errno) ||
((const xmlChar *)endptr == numstr)) {
cli_dbgmsg("cli_scanxar: XML element value invalid\n");
return CL_EFORMAT;
} else if (numval < 0) {
cli_dbgmsg("cli_scanxar: XML element value %li\n", numval);
return CL_EFORMAT;
}
*value = numval;
return CL_SUCCESS;
}
}
cli_dbgmsg("cli_scanxar: No text for XML element\n");
return CL_EFORMAT;
}
/*
xar_get_checksum_values - extract checksum and hash algorithm from xml element
parameters:
reader - xmlTextReaderPtr
cksum - pointer to char* for returning checksum value.
hash - pointer to int for returning checksum algorithm.
returns - void
*/
static void xar_get_checksum_values(xmlTextReaderPtr reader, unsigned char **cksum, int *hash)
{
xmlChar *style = xmlTextReaderGetAttribute(reader, (const xmlChar *)"style");
const xmlChar *xmlval;
*hash = XAR_CKSUM_NONE;
if (style == NULL) {
cli_dbgmsg("cli_scaxar: xmlTextReaderGetAttribute no style attribute "
"for checksum element\n");
} else {
cli_dbgmsg("cli_scanxar: checksum algorithm is %s.\n", style);
if (0 == xmlStrcasecmp(style, (const xmlChar *)"sha1")) {
*hash = XAR_CKSUM_SHA1;
} else if (0 == xmlStrcasecmp(style, (const xmlChar *)"md5")) {
*hash = XAR_CKSUM_MD5;
} else {
cli_dbgmsg("cli_scanxar: checksum algorithm %s is unsupported.\n", style);
*hash = XAR_CKSUM_OTHER;
}
}
if (style != NULL)
xmlFree(style);
if (xmlTextReaderRead(reader) == 1 && xmlTextReaderNodeType(reader) == XML_READER_TYPE_TEXT) {
xmlval = xmlTextReaderConstValue(reader);
if (xmlval) {
cli_dbgmsg("cli_scanxar: checksum value is %s.\n", xmlval);
if (((*hash == XAR_CKSUM_SHA1) && (xmlStrlen(xmlval) == 2 * SHA1_HASH_SIZE)) ||
((*hash == XAR_CKSUM_MD5) && (xmlStrlen(xmlval) == 2 * MD5_HASH_SIZE))) {
*cksum = xmlStrdup(xmlval);
} else {
cli_dbgmsg("cli_scanxar: checksum type is unknown or length is invalid.\n");
*hash = XAR_CKSUM_OTHER;
*cksum = NULL;
}
} else {
*cksum = NULL;
cli_dbgmsg("cli_scanxar: xmlTextReaderConstValue() returns NULL for checksum value.\n");
}
} else
cli_dbgmsg("cli_scanxar: No text for XML checksum element.\n");
}
/*
xar_get_toc_data_values - return the values of a <data> or <ea> xml element that represent
an extent of data on the heap.
parameters:
reader - xmlTextReaderPtr
length - pointer to long for returning value of the <length> element.
offset - pointer to long for returning value of the <offset> element.
size - pointer to long for returning value of the <size> element.
encoding - pointer to int for returning indication of the <encoding> style attribute.
a_cksum - pointer to char* for return archived checksum value.
a_hash - pointer to int for returning archived checksum algorithm.
e_cksum - pointer to char* for return extracted checksum value.
e_hash - pointer to int for returning extracted checksum algorithm.
returns - CL_FORMAT, CL_SUCCESS, CL_BREAK. CL_BREAK indicates no more <data>/<ea> element.
*/
static int xar_get_toc_data_values(xmlTextReaderPtr reader, size_t *length, size_t *offset, size_t *size, int *encoding,
unsigned char **a_cksum, int *a_hash, unsigned char **e_cksum, int *e_hash)
{
const xmlChar *name;
int indata = 0, inea = 0;
int rc, gotoffset = 0, gotlength = 0, gotsize = 0;
*a_cksum = NULL;
*a_hash = XAR_CKSUM_NONE;
*e_cksum = NULL;
*e_hash = XAR_CKSUM_NONE;
*encoding = CL_TYPE_ANY;
rc = xmlTextReaderRead(reader);
while (rc == 1) {
name = xmlTextReaderConstLocalName(reader);
if (indata || inea) {
/* cli_dbgmsg("cli_scanxar: xmlTextReaderRead read %s\n", name); */
if (xmlStrEqual(name, (const xmlChar *)"offset") &&
xmlTextReaderNodeType(reader) == XML_READER_TYPE_ELEMENT) {
if (CL_SUCCESS == xar_get_numeric_from_xml_element(reader, offset))
gotoffset = 1;
} else if (xmlStrEqual(name, (const xmlChar *)"length") &&
xmlTextReaderNodeType(reader) == XML_READER_TYPE_ELEMENT) {
if (CL_SUCCESS == xar_get_numeric_from_xml_element(reader, length))
gotlength = 1;
} else if (xmlStrEqual(name, (const xmlChar *)"size") &&
xmlTextReaderNodeType(reader) == XML_READER_TYPE_ELEMENT) {
if (CL_SUCCESS == xar_get_numeric_from_xml_element(reader, size))
gotsize = 1;
} else if (xmlStrEqual(name, (const xmlChar *)"archived-checksum") &&
xmlTextReaderNodeType(reader) == XML_READER_TYPE_ELEMENT) {
cli_dbgmsg("cli_scanxar: <archived-checksum>:\n");
xar_get_checksum_values(reader, a_cksum, a_hash);
} else if ((xmlStrEqual(name, (const xmlChar *)"extracted-checksum") ||
xmlStrEqual(name, (const xmlChar *)"unarchived-checksum")) &&
xmlTextReaderNodeType(reader) == XML_READER_TYPE_ELEMENT) {
cli_dbgmsg("cli_scanxar: <extracted-checksum>:\n");
xar_get_checksum_values(reader, e_cksum, e_hash);
} else if (xmlStrEqual(name, (const xmlChar *)"encoding") &&
xmlTextReaderNodeType(reader) == XML_READER_TYPE_ELEMENT) {
xmlChar *style = xmlTextReaderGetAttribute(reader, (const xmlChar *)"style");
if (style == NULL) {
cli_dbgmsg("cli_scaxar: xmlTextReaderGetAttribute no style attribute "
"for encoding element\n");
*encoding = CL_TYPE_ANY;
} else if (xmlStrEqual(style, (const xmlChar *)"application/x-gzip")) {
cli_dbgmsg("cli_scanxar: encoding = application/x-gzip.\n");
*encoding = CL_TYPE_GZ;
} else if (xmlStrEqual(style, (const xmlChar *)"application/octet-stream")) {
cli_dbgmsg("cli_scanxar: encoding = application/octet-stream.\n");
*encoding = CL_TYPE_ANY;
} else if (xmlStrEqual(style, (const xmlChar *)"application/x-bzip2")) {
cli_dbgmsg("cli_scanxar: encoding = application/x-bzip2.\n");
*encoding = CL_TYPE_BZ;
} else if (xmlStrEqual(style, (const xmlChar *)"application/x-lzma")) {
cli_dbgmsg("cli_scanxar: encoding = application/x-lzma.\n");
*encoding = CL_TYPE_7Z;
} else if (xmlStrEqual(style, (const xmlChar *)"application/x-xz")) {
cli_dbgmsg("cli_scanxar: encoding = application/x-xz.\n");
*encoding = CL_TYPE_XZ;
} else {
cli_dbgmsg("cli_scaxar: unknown style value=%s for encoding element\n", style);
*encoding = CL_TYPE_ANY;
}
if (style != NULL)
xmlFree(style);
} else if (indata && xmlStrEqual(name, (const xmlChar *)"data") &&
xmlTextReaderNodeType(reader) == XML_READER_TYPE_END_ELEMENT) {
break;
} else if (inea && xmlStrEqual(name, (const xmlChar *)"ea") &&
xmlTextReaderNodeType(reader) == XML_READER_TYPE_END_ELEMENT) {
break;
}
} else {
if (xmlTextReaderNodeType(reader) == XML_READER_TYPE_ELEMENT) {
if (xmlStrEqual(name, (const xmlChar *)"data")) {
cli_dbgmsg("cli_scanxar: xmlTextReaderRead read <data>\n");
indata = 1;
} else if (xmlStrEqual(name, (const xmlChar *)"ea")) {
cli_dbgmsg("cli_scanxar: xmlTextReaderRead read <ea>\n");
inea = 1;
}
} else if ((xmlTextReaderNodeType(reader) == XML_READER_TYPE_END_ELEMENT) &&
xmlStrEqual(name, (const xmlChar *)"xar")) {
cli_dbgmsg("cli_scanxar: finished parsing xar TOC.\n");
break;
}
}
rc = xmlTextReaderRead(reader);
}
if (gotoffset && gotlength && gotsize) {
rc = CL_SUCCESS;
} else if (0 == gotoffset + gotlength + gotsize)
rc = CL_BREAK;
else
rc = CL_EFORMAT;
return rc;
}
/*
xar_process_subdocument - check TOC for xml subdocument. If found, extract and
scan in memory.
Parameters:
reader - xmlTextReaderPtr
ctx - pointer to cli_ctx
Returns:
CL_SUCCESS - subdoc found and clean scan (or virus found and SCAN_ALLMATCHES), or no subdocument
other - error return code from cli_magic_scan_buff()
*/
static int xar_scan_subdocuments(xmlTextReaderPtr reader, cli_ctx *ctx)
{
int rc = CL_SUCCESS, subdoc_len, fd;
xmlChar *subdoc;
const xmlChar *name;
char *tmpname;
while (xmlTextReaderRead(reader) == 1) {
name = xmlTextReaderConstLocalName(reader);
if (name == NULL) {
cli_dbgmsg("cli_scanxar: xmlTextReaderConstLocalName() no name.\n");
rc = CL_EFORMAT;
break;
}
if (xmlStrEqual(name, (const xmlChar *)"toc") &&
xmlTextReaderNodeType(reader) == XML_READER_TYPE_ELEMENT)
return CL_SUCCESS;
if (xmlStrEqual(name, (const xmlChar *)"subdoc") &&
xmlTextReaderNodeType(reader) == XML_READER_TYPE_ELEMENT) {
subdoc = xmlTextReaderReadInnerXml(reader);
if (subdoc == NULL) {
cli_dbgmsg("cli_scanxar: no content in subdoc element.\n");
xmlTextReaderNext(reader);
continue;
}
subdoc_len = xmlStrlen(subdoc);
cli_dbgmsg("cli_scanxar: in-memory scan of xml subdocument, len %i.\n", subdoc_len);
rc = cli_magic_scan_buff(subdoc, subdoc_len, ctx, NULL, LAYER_ATTRIBUTES_NONE);
/* make a file to leave if --leave-temps in effect */
if (ctx->engine->keeptmp) {
if ((rc = cli_gentempfd(ctx->this_layer_tmpdir, &tmpname, &fd)) != CL_SUCCESS) {
cli_dbgmsg("cli_scanxar: Can't create temporary file for subdocument.\n");
} else {
cli_dbgmsg("cli_scanxar: Writing subdoc to temp file %s.\n", tmpname);
if (cli_writen(fd, subdoc, subdoc_len) == (size_t)-1) {
cli_dbgmsg("cli_scanxar: cli_writen error writing subdoc temporary file.\n");
rc = CL_EWRITE;
}
rc = xar_cleanup_temp_file(ctx, fd, tmpname);
tmpname = NULL;
}
}
xmlFree(subdoc);
if (rc != CL_SUCCESS)
return rc;
xmlTextReaderNext(reader);
}
}
return rc;
}
static void *xar_hash_init(int hash, void **sc, void **mc)
{
if (!sc && !mc)
return NULL;
switch (hash) {
case XAR_CKSUM_SHA1:
*sc = cl_hash_init("sha1");
if (!(*sc)) {
return NULL;
}
return *sc;
case XAR_CKSUM_MD5:
*mc = cl_hash_init("md5");
if (!(*mc)) {
return NULL;
}
return *mc;
case XAR_CKSUM_OTHER:
case XAR_CKSUM_NONE:
default:
return NULL;
}
}
static void xar_hash_update(void *hash_ctx, void *data, unsigned long size, int hash)
{
if (!hash_ctx || !data || !size)
return;
switch (hash) {
case XAR_CKSUM_NONE:
case XAR_CKSUM_OTHER:
return;
}
cl_update_hash(hash_ctx, data, size);
}
static void xar_hash_final(void *hash_ctx, void *result, int hash)
{
if (!hash_ctx || !result)
return;
switch (hash) {
case XAR_CKSUM_OTHER:
case XAR_CKSUM_NONE:
return;
}
cl_finish_hash(hash_ctx, result);
}
static int xar_hash_check(int hash, const void *result, const void *expected)
{
int len;
if (!result || !expected)
return 1;
switch (hash) {
case XAR_CKSUM_SHA1:
len = SHA1_HASH_SIZE;
break;
case XAR_CKSUM_MD5:
len = MD5_HASH_SIZE;
break;
case XAR_CKSUM_OTHER:
case XAR_CKSUM_NONE:
default:
return 1;
}
return memcmp(result, expected, len);
}
/*
cli_scanxar - scan an xar archive.
Parameters:
ctx - pointer to cli_ctx.
returns - CL_SUCCESS or CL_ error code.
*/
int cli_scanxar(cli_ctx *ctx)
{
int rc = CL_SUCCESS;
unsigned int cksum_fails = 0;
unsigned int extract_errors = 0;
int fd = -1;
struct xar_header hdr;
fmap_t *map = ctx->fmap;
size_t length, offset, size, at;
int encoding;
z_stream strm;
char *toc, *tmpname = NULL;
xmlTextReaderPtr reader = NULL;
int a_hash, e_hash;
unsigned char *a_cksum = NULL, *e_cksum = NULL;
void *a_hash_ctx = NULL, *e_hash_ctx = NULL;
char e_hash_result[SHA1_HASH_SIZE];
char a_hash_result[SHA1_HASH_SIZE];
memset(&strm, 0x00, sizeof(z_stream));
/* retrieve xar header */
if (fmap_readn(ctx->fmap, &hdr, 0, sizeof(hdr)) != sizeof(hdr)) {
cli_dbgmsg("cli_scanxar: Invalid header, too short.\n");
return CL_EFORMAT;
}
hdr.magic = be32_to_host(hdr.magic);
if (hdr.magic == XAR_HEADER_MAGIC) {
cli_dbgmsg("cli_scanxar: Matched magic\n");
} else {
cli_dbgmsg("cli_scanxar: Invalid magic\n");
return CL_EFORMAT;
}
hdr.size = be16_to_host(hdr.size);
hdr.version = be16_to_host(hdr.version);
hdr.toc_length_compressed = be64_to_host(hdr.toc_length_compressed);
hdr.toc_length_decompressed = be64_to_host(hdr.toc_length_decompressed);
hdr.chksum_alg = be32_to_host(hdr.chksum_alg);
/* cli_dbgmsg("hdr.magic %x\n", hdr.magic); */
/* cli_dbgmsg("hdr.size %i\n", hdr.size); */
/* cli_dbgmsg("hdr.version %i\n", hdr.version); */
/* cli_dbgmsg("hdr.toc_length_compressed %lu\n", hdr.toc_length_compressed); */
/* cli_dbgmsg("hdr.toc_length_decompressed %lu\n", hdr.toc_length_decompressed); */
/* cli_dbgmsg("hdr.chksum_alg %i\n", hdr.chksum_alg); */
/* Uncompress TOC */
strm.next_in = (unsigned char *)fmap_need_off_once(ctx->fmap, hdr.size, hdr.toc_length_compressed);
if (strm.next_in == NULL) {
cli_dbgmsg("cli_scanxar: fmap_need_off_once fails on TOC.\n");
return CL_EREAD;
}
strm.avail_in = hdr.toc_length_compressed;
toc = cli_max_malloc(hdr.toc_length_decompressed + 1);
if (toc == NULL) {
cli_dbgmsg("cli_scanxar: cli_max_malloc fails on TOC decompress buffer.\n");
return CL_EMEM;
}
toc[hdr.toc_length_decompressed] = '\0';
strm.avail_out = hdr.toc_length_decompressed;
strm.next_out = (unsigned char *)toc;
rc = inflateInit(&strm);
if (rc != Z_OK) {
cli_dbgmsg("cli_scanxar:inflateInit error %i \n", rc);
rc = CL_EFORMAT;
goto exit_toc;
}
rc = inflate(&strm, Z_SYNC_FLUSH);
if (rc != Z_OK && rc != Z_STREAM_END) {
inflateEnd(&strm);
cli_dbgmsg("cli_scanxar:inflate error %i \n", rc);
rc = CL_EFORMAT;
goto exit_toc;
}
rc = inflateEnd(&strm);
if (rc != Z_OK) {
cli_dbgmsg("cli_scanxar:inflateEnd error %i \n", rc);
rc = CL_EFORMAT;
goto exit_toc;
}
if (hdr.toc_length_decompressed != strm.total_out) {
cli_dbgmsg("TOC decompress length %" PRIu64 " does not match amount decompressed %lu\n",
hdr.toc_length_decompressed, strm.total_out);
toc[strm.total_out] = '\0';
hdr.toc_length_decompressed = strm.total_out;
}
/* cli_dbgmsg("cli_scanxar: TOC xml:\n%s\n", toc); */
/* printf("cli_scanxar: TOC xml:\n%s\n", toc); */
/* cli_dbgmsg("cli_scanxar: TOC end:\n"); */
/* printf("cli_scanxar: TOC end:\n"); */
/* scan the xml */
cli_dbgmsg("cli_scanxar: scanning xar TOC xml in memory.\n");
rc = cli_magic_scan_buff(toc, hdr.toc_length_decompressed, ctx, NULL, LAYER_ATTRIBUTES_NONE);
if (rc != CL_SUCCESS) {
goto exit_toc;
}
/* make a file to leave if --leave-temps in effect */
if (ctx->engine->keeptmp) {
if ((rc = cli_gentempfd(ctx->this_layer_tmpdir, &tmpname, &fd)) != CL_SUCCESS) {
cli_dbgmsg("cli_scanxar: Can't create temporary file for TOC.\n");
goto exit_toc;
}
if (cli_writen(fd, toc, hdr.toc_length_decompressed) == (size_t)-1) {
cli_dbgmsg("cli_scanxar: cli_writen error writing TOC.\n");
rc = CL_EWRITE;
xar_cleanup_temp_file(ctx, fd, tmpname);
goto exit_toc;
}
rc = xar_cleanup_temp_file(ctx, fd, tmpname);
tmpname = NULL;
if (rc != CL_SUCCESS)
goto exit_toc;
}
reader = xmlReaderForMemory(toc, hdr.toc_length_decompressed, "noname.xml", NULL, CLAMAV_MIN_XMLREADER_FLAGS);
if (reader == NULL) {
cli_dbgmsg("cli_scanxar: xmlReaderForMemory error for TOC\n");
goto exit_toc;
}
rc = xar_scan_subdocuments(reader, ctx);
if (rc != CL_SUCCESS) {
cli_dbgmsg("xar_scan_subdocuments returns %i.\n", rc);
goto exit_reader;
}
/* Walk the TOC XML and extract files */
fd = -1;
tmpname = NULL;
while (CL_SUCCESS == (rc = xar_get_toc_data_values(reader, &length, &offset, &size, &encoding,
&a_cksum, &a_hash, &e_cksum, &e_hash))) {
int do_extract_cksum = 1;
unsigned char *blockp;
void *a_sc, *e_sc;
void *a_mc, *e_mc;
char *expected;
/* clean up temp file from previous loop iteration */
if (fd > -1 && tmpname) {
rc = xar_cleanup_temp_file(ctx, fd, tmpname);
tmpname = NULL;
if (rc != CL_SUCCESS)
goto exit_reader;
}
at = offset + hdr.toc_length_compressed + hdr.size;
if ((rc = cli_gentempfd(ctx->this_layer_tmpdir, &tmpname, &fd)) != CL_SUCCESS) {
cli_dbgmsg("cli_scanxar: Can't generate temporary file.\n");
goto exit_reader;
}
cli_dbgmsg("cli_scanxar: decompress into temp file:\n%s, size %zu,\n"
"from xar heap offset %zu length %zu\n",
tmpname, size, offset, length);
a_hash_ctx = xar_hash_init(a_hash, &a_sc, &a_mc);
e_hash_ctx = xar_hash_init(e_hash, &e_sc, &e_mc);
switch (encoding) {
case CL_TYPE_GZ:
/* inflate gzip directly because file segments do not contain magic */
memset(&strm, 0, sizeof(strm));
if ((rc = inflateInit(&strm)) != Z_OK) {
cli_dbgmsg("cli_scanxar: InflateInit failed: %d\n", rc);
rc = CL_EFORMAT;
extract_errors++;
break;
}
while ((size_t)at < map->len && (unsigned long)at < offset + hdr.toc_length_compressed + hdr.size + length) {
unsigned long avail_in;
void *next_in;
unsigned int bytes = MIN(map->len - at, map->pgsz);
bytes = MIN(length, bytes);
if (!(strm.next_in = next_in = (void *)fmap_need_off_once(map, at, bytes))) {
cli_dbgmsg("cli_scanxar: Can't read %u bytes @ %lu.\n", bytes, (long unsigned)at);
inflateEnd(&strm);
rc = CL_EREAD;
goto exit_tmpfile;
}
at += bytes;
strm.avail_in = avail_in = bytes;
do {
int inf, outsize = 0;
unsigned char buff[FILEBUFF];
strm.avail_out = sizeof(buff);
strm.next_out = buff;
inf = inflate(&strm, Z_SYNC_FLUSH);
if (inf != Z_OK && inf != Z_STREAM_END && inf != Z_BUF_ERROR) {
cli_dbgmsg("cli_scanxar: inflate error %i %s.\n", inf, strm.msg ? strm.msg : "");
rc = CL_EFORMAT;
extract_errors++;
break;
}
bytes = sizeof(buff) - strm.avail_out;
if (e_hash_ctx != NULL)
xar_hash_update(e_hash_ctx, buff, bytes, e_hash);
if (cli_writen(fd, buff, bytes) == (size_t)-1) {
cli_dbgmsg("cli_scanxar: cli_writen error file %s.\n", tmpname);
inflateEnd(&strm);
rc = CL_EWRITE;
goto exit_tmpfile;
}
outsize += sizeof(buff) - strm.avail_out;
if (cli_checklimits("cli_scanxar", ctx, outsize, 0, 0) != CL_CLEAN) {
break;
}
if (inf == Z_STREAM_END) {
break;
}
} while (strm.avail_out == 0);
if (rc != CL_SUCCESS)
break;
avail_in -= strm.avail_in;
if (a_hash_ctx != NULL)
xar_hash_update(a_hash_ctx, next_in, avail_in, a_hash);
}
inflateEnd(&strm);
break;
case CL_TYPE_7Z:
#define CLI_LZMA_OBUF_SIZE 1024 * 1024
#define CLI_LZMA_HDR_SIZE LZMA_PROPS_SIZE + 8
#define CLI_LZMA_IBUF_SIZE CLI_LZMA_OBUF_SIZE >> 2 /* estimated compression ratio 25% */
{
struct CLI_LZMA lz;
unsigned long in_remaining = MIN(length, map->len - at);
unsigned long out_size = 0;
unsigned char *buff = __lzma_wrap_alloc(NULL, CLI_LZMA_OBUF_SIZE);
int lret;
if (length > in_remaining)
length = in_remaining;
memset(&lz, 0, sizeof(lz));
if (buff == NULL) {
cli_dbgmsg("cli_scanxar: memory request for lzma decompression buffer fails.\n");
rc = CL_EMEM;
goto exit_tmpfile;
}
blockp = (void *)fmap_need_off_once(map, at, CLI_LZMA_HDR_SIZE);
if (blockp == NULL) {
char errbuff[128];
cli_strerror(errno, errbuff, sizeof(errbuff));
cli_dbgmsg("cli_scanxar: Can't read %i bytes @ %zu, errno:%s.\n",
CLI_LZMA_HDR_SIZE, at, errbuff);
rc = CL_EREAD;
__lzma_wrap_free(NULL, buff);
goto exit_tmpfile;
}
lz.next_in = blockp;
lz.avail_in = CLI_LZMA_HDR_SIZE;
if (a_hash_ctx != NULL)
xar_hash_update(a_hash_ctx, blockp, CLI_LZMA_HDR_SIZE, a_hash);
lret = cli_LzmaInit(&lz, 0);
if (lret != LZMA_RESULT_OK) {
cli_dbgmsg("cli_scanxar: cli_LzmaInit() fails: %i.\n", lret);
rc = CL_EFORMAT;
__lzma_wrap_free(NULL, buff);
extract_errors++;
break;
}
at += CLI_LZMA_HDR_SIZE;
in_remaining -= CLI_LZMA_HDR_SIZE;
while (at < map->len && at < offset + (size_t)hdr.toc_length_compressed + (size_t)hdr.size + length) {
SizeT avail_in;
SizeT avail_out;
void *next_in;
unsigned long in_consumed;
lz.next_out = buff;
lz.avail_out = CLI_LZMA_OBUF_SIZE;
lz.avail_in = avail_in = MIN(CLI_LZMA_IBUF_SIZE, in_remaining);
lz.next_in = next_in = (void *)fmap_need_off_once(map, at, lz.avail_in);
if (lz.next_in == NULL) {
char errbuff[128];
cli_strerror(errno, errbuff, sizeof(errbuff));
cli_dbgmsg("cli_scanxar: Can't read %zu bytes @ %zu, errno: %s.\n",
lz.avail_in, at, errbuff);
rc = CL_EREAD;
__lzma_wrap_free(NULL, buff);
cli_LzmaShutdown(&lz);
goto exit_tmpfile;
}
lret = cli_LzmaDecode(&lz);
if (lret != LZMA_RESULT_OK && lret != LZMA_STREAM_END) {
cli_dbgmsg("cli_scanxar: cli_LzmaDecode() fails: %i.\n", lret);
rc = CL_EFORMAT;
extract_errors++;
break;
}
in_consumed = avail_in - lz.avail_in;
in_remaining -= in_consumed;
at += in_consumed;
avail_out = CLI_LZMA_OBUF_SIZE - lz.avail_out;
if (avail_out == 0)
cli_dbgmsg("cli_scanxar: cli_LzmaDecode() produces no output for "
"avail_in %llu, avail_out %llu.\n",
(long long unsigned)avail_in, (long long unsigned)avail_out);
if (a_hash_ctx != NULL)
xar_hash_update(a_hash_ctx, next_in, in_consumed, a_hash);
if (e_hash_ctx != NULL)
xar_hash_update(e_hash_ctx, buff, avail_out, e_hash);
/* Write a decompressed block. */
/* cli_dbgmsg("Writing %li bytes to LZMA decompress temp file, " */
/* "consumed %li of %li available compressed bytes.\n", */
/* avail_out, in_consumed, avail_in); */
if (cli_writen(fd, buff, avail_out) == (size_t)-1) {
cli_dbgmsg("cli_scanxar: cli_writen error writing lzma temp file for %llu bytes.\n",
(long long unsigned)avail_out);
__lzma_wrap_free(NULL, buff);
cli_LzmaShutdown(&lz);
rc = CL_EWRITE;
goto exit_tmpfile;
}
/* Check file size limitation. */
out_size += avail_out;
if (cli_checklimits("cli_scanxar", ctx, out_size, 0, 0) != CL_CLEAN) {
break;
}
if (lret == LZMA_STREAM_END)
break;
}
cli_LzmaShutdown(&lz);
__lzma_wrap_free(NULL, buff);
} break;
case CL_TYPE_ANY:
default:
case CL_TYPE_BZ:
case CL_TYPE_XZ:
/* for uncompressed, bzip2, xz, and unknown, just pull the file, cli_magic_scan_desc does the rest */
do_extract_cksum = 0;
{
size_t writelen = MIN(map->len - at, length);
if (ctx->engine->maxfilesize)
writelen = MIN((size_t)(ctx->engine->maxfilesize), writelen);
if (!(blockp = (void *)fmap_need_off_once(map, at, writelen))) {
char errbuff[128];
cli_strerror(errno, errbuff, sizeof(errbuff));
cli_dbgmsg("cli_scanxar: Can't read %zu bytes @ %zu, errno:%s.\n",
writelen, at, errbuff);
rc = CL_EREAD;
goto exit_tmpfile;
}
if (a_hash_ctx != NULL)
xar_hash_update(a_hash_ctx, blockp, writelen, a_hash);
if (cli_writen(fd, blockp, writelen) == (size_t)-1) {
cli_dbgmsg("cli_scanxar: cli_writen error %zu bytes @ %zu.\n", writelen, at);
rc = CL_EWRITE;
goto exit_tmpfile;
}
/*break;*/
}
} /* end of switch */
if (a_hash_ctx != NULL) {
xar_hash_final(a_hash_ctx, a_hash_result, a_hash);
a_hash_ctx = NULL;
} else if (rc == CL_SUCCESS) {
cli_dbgmsg("cli_scanxar: archived-checksum missing.\n");
cksum_fails++;
}
if (e_hash_ctx != NULL) {
xar_hash_final(e_hash_ctx, e_hash_result, e_hash);
e_hash_ctx = NULL;
} else if (rc == CL_SUCCESS) {
cli_dbgmsg("cli_scanxar: extracted-checksum(unarchived-checksum) missing.\n");
cksum_fails++;
}
if (rc == CL_SUCCESS) {
if (a_cksum != NULL) {
expected = cli_hex2str((char *)a_cksum);
if (xar_hash_check(a_hash, a_hash_result, expected) != 0) {
cli_dbgmsg("cli_scanxar: archived-checksum mismatch.\n");
cksum_fails++;
} else {
cli_dbgmsg("cli_scanxar: archived-checksum matched.\n");
}
free(expected);
}
if (e_cksum != NULL) {
if (do_extract_cksum) {
expected = cli_hex2str((char *)e_cksum);
if (xar_hash_check(e_hash, e_hash_result, expected) != 0) {
cli_dbgmsg("cli_scanxar: extracted-checksum mismatch.\n");
cksum_fails++;
} else {
cli_dbgmsg("cli_scanxar: extracted-checksum matched.\n");
}
free(expected);
}
}
rc = cli_magic_scan_desc(fd, tmpname, ctx, NULL, LAYER_ATTRIBUTES_NONE); /// TODO: collect file names in xar_get_toc_data_values()
if (rc != CL_SUCCESS) {
goto exit_tmpfile;
}
}
if (a_cksum != NULL) {
xmlFree(a_cksum);
a_cksum = NULL;
}
if (e_cksum != NULL) {
xmlFree(e_cksum);
e_cksum = NULL;
}
}
exit_tmpfile:
xar_cleanup_temp_file(ctx, fd, tmpname);
if (a_hash_ctx != NULL)
xar_hash_final(a_hash_ctx, a_hash_result, a_hash);
if (e_hash_ctx != NULL)
xar_hash_final(e_hash_ctx, e_hash_result, e_hash);
exit_reader:
if (a_cksum != NULL)
xmlFree(a_cksum);
if (e_cksum != NULL)
xmlFree(e_cksum);
xmlTextReaderClose(reader);
xmlFreeTextReader(reader);
exit_toc:
free(toc);
if (rc == CL_BREAK)
rc = CL_SUCCESS;
if (cksum_fails + extract_errors != 0) {
cli_dbgmsg("cli_scanxar: %u checksum errors and %u extraction errors.\n",
cksum_fails, extract_errors);
}
return rc;
}
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