694 lines
16 KiB
C
694 lines
16 KiB
C
/*
|
|
* Copyright (C) 2013-2022 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
|
|
* Copyright (C) 2007-2013 Sourcefire, Inc.
|
|
*
|
|
* Authors: Nigel Horne
|
|
*
|
|
* 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 <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <errno.h>
|
|
#include <fcntl.h>
|
|
#include <sys/types.h>
|
|
#include <sys/stat.h>
|
|
|
|
#ifdef HAVE_SYS_PARAM_H
|
|
#include <sys/param.h> /* for NAME_MAX */
|
|
#endif
|
|
|
|
#ifdef C_DARWIN
|
|
#include <sys/types.h>
|
|
#endif
|
|
|
|
#ifdef HAVE_UNISTD_H
|
|
#include <unistd.h>
|
|
#endif
|
|
|
|
#include "clamav.h"
|
|
#include "others.h"
|
|
#include "mbox.h"
|
|
#include "matcher.h"
|
|
#include "scanners.h"
|
|
#include "filetypes.h"
|
|
|
|
#include <assert.h>
|
|
|
|
/* Scheduled for rewrite in 0.94 (bb#804). Disabling for now */
|
|
/* #define MAX_SCAN_SIZE 20*1024 /\* */
|
|
/* * The performance benefit of scanning */
|
|
/* * early disappears on medium and */
|
|
/* * large sized files */
|
|
/* *\/ */
|
|
|
|
static const char *blobGetFilename(const blob *b);
|
|
|
|
blob *
|
|
blobCreate(void)
|
|
{
|
|
#ifdef CL_DEBUG
|
|
blob *b = (blob *)cli_calloc(1, sizeof(blob));
|
|
if (b)
|
|
b->magic = BLOBCLASS;
|
|
cli_dbgmsg("blobCreate\n");
|
|
return b;
|
|
#else
|
|
return (blob *)cli_calloc(1, sizeof(blob));
|
|
#endif
|
|
}
|
|
|
|
void blobDestroy(blob *b)
|
|
{
|
|
#ifdef CL_DEBUG
|
|
cli_dbgmsg("blobDestroy %d\n", b->magic);
|
|
#else
|
|
cli_dbgmsg("blobDestroy\n");
|
|
#endif
|
|
|
|
assert(b != NULL);
|
|
#ifdef CL_DEBUG
|
|
assert(b->magic == BLOBCLASS);
|
|
#endif
|
|
|
|
if (b->name)
|
|
free(b->name);
|
|
if (b->data)
|
|
free(b->data);
|
|
#ifdef CL_DEBUG
|
|
b->magic = INVALIDCLASS;
|
|
#endif
|
|
free(b);
|
|
}
|
|
|
|
void blobArrayDestroy(blob *blobList[], int n)
|
|
{
|
|
assert(blobList != NULL);
|
|
|
|
while (--n >= 0) {
|
|
cli_dbgmsg("blobArrayDestroy: %d\n", n);
|
|
if (blobList[n]) {
|
|
blobDestroy(blobList[n]);
|
|
blobList[n] = NULL;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* No longer needed to be growable, so turn into a normal memory area which
|
|
* the caller must free. The passed blob is destroyed
|
|
*/
|
|
void *
|
|
blobToMem(blob *b)
|
|
{
|
|
void *ret;
|
|
|
|
assert(b != NULL);
|
|
#ifdef CL_DEBUG
|
|
assert(b->magic == BLOBCLASS);
|
|
#endif
|
|
|
|
if (!b->isClosed)
|
|
blobClose(b);
|
|
if (b->name)
|
|
free(b->name);
|
|
#ifdef CL_DEBUG
|
|
b->magic = INVALIDCLASS;
|
|
#endif
|
|
ret = (void *)b->data;
|
|
free(b);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*ARGSUSED*/
|
|
void blobSetFilename(blob *b, const char *dir, const char *filename)
|
|
{
|
|
assert(b != NULL);
|
|
#ifdef CL_DEBUG
|
|
assert(b->magic == BLOBCLASS);
|
|
#endif
|
|
assert(filename != NULL);
|
|
|
|
UNUSEDPARAM(dir);
|
|
|
|
cli_dbgmsg("blobSetFilename: %s\n", filename);
|
|
|
|
if (b->name)
|
|
free(b->name);
|
|
|
|
b->name = cli_strdup(filename);
|
|
|
|
if (b->name)
|
|
sanitiseName(b->name);
|
|
}
|
|
|
|
static const char *
|
|
blobGetFilename(const blob *b)
|
|
{
|
|
assert(b != NULL);
|
|
#ifdef CL_DEBUG
|
|
assert(b->magic == BLOBCLASS);
|
|
#endif
|
|
|
|
return b->name;
|
|
}
|
|
|
|
/*
|
|
* Returns <0 for failure
|
|
*/
|
|
int blobAddData(blob *b, const unsigned char *data, size_t len)
|
|
{
|
|
#if HAVE_CLI_GETPAGESIZE
|
|
static int pagesize = 0;
|
|
int growth;
|
|
#endif
|
|
|
|
assert(b != NULL);
|
|
#ifdef CL_DEBUG
|
|
assert(b->magic == BLOBCLASS);
|
|
#endif
|
|
assert(data != NULL);
|
|
|
|
if (len == 0)
|
|
return 0;
|
|
|
|
if (b->isClosed) {
|
|
/*
|
|
* Should be cli_dbgmsg, but I want to see them for now,
|
|
* and cli_dbgmsg doesn't support debug levels
|
|
*/
|
|
cli_warnmsg("Reopening closed blob\n");
|
|
b->isClosed = 0;
|
|
}
|
|
/*
|
|
* The payoff here is between reducing the number of calls to
|
|
* malloc/realloc and not overallocating memory. A lot of machines
|
|
* are more tight with memory than one may imagine which is why
|
|
* we don't just allocate a *huge* amount and be done with it. Closing
|
|
* the blob helps because that reclaims memory. If you know the maximum
|
|
* size of a blob before you start adding data, use blobGrow() that's
|
|
* the most optimum
|
|
*/
|
|
#if HAVE_CLI_GETPAGESIZE
|
|
if (pagesize == 0) {
|
|
pagesize = cli_getpagesize();
|
|
if (pagesize == 0)
|
|
pagesize = 4096;
|
|
}
|
|
growth = pagesize;
|
|
if (len >= (size_t)pagesize)
|
|
growth = ((len / pagesize) + 1) * pagesize;
|
|
|
|
/*cli_dbgmsg("blobGrow: b->size %lu, b->len %lu, len %lu, growth = %u\n",
|
|
b->size, b->len, len, growth);*/
|
|
|
|
if (b->data == NULL) {
|
|
assert(b->len == 0);
|
|
assert(b->size == 0);
|
|
|
|
b->size = growth;
|
|
b->data = cli_malloc(growth);
|
|
if (NULL == b->data) {
|
|
b->size = 0;
|
|
return -1;
|
|
}
|
|
} else if (b->size < b->len + (off_t)len) {
|
|
unsigned char *p = cli_realloc(b->data, b->size + growth);
|
|
|
|
if (p == NULL)
|
|
return -1;
|
|
|
|
b->size += growth;
|
|
b->data = p;
|
|
}
|
|
#else
|
|
if (b->data == NULL) {
|
|
assert(b->len == 0);
|
|
assert(b->size == 0);
|
|
|
|
b->size = (off_t)len * 4;
|
|
b->data = cli_malloc(b->size);
|
|
if (NULL == b->data) {
|
|
b->size = 0;
|
|
return -1;
|
|
}
|
|
} else if (b->size < b->len + (off_t)len) {
|
|
unsigned char *p = cli_realloc(b->data, b->size + (len * 4));
|
|
|
|
if (p == NULL)
|
|
return -1;
|
|
|
|
b->size += (off_t)len * 4;
|
|
b->data = p;
|
|
}
|
|
#endif
|
|
|
|
if (b->data) {
|
|
memcpy(&b->data[b->len], data, len);
|
|
b->len += (off_t)len;
|
|
} else {
|
|
b->size = 0;
|
|
return -1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
unsigned char *
|
|
blobGetData(const blob *b)
|
|
{
|
|
assert(b != NULL);
|
|
#ifdef CL_DEBUG
|
|
assert(b->magic == BLOBCLASS);
|
|
#endif
|
|
|
|
if (b->len == 0)
|
|
return NULL;
|
|
return b->data;
|
|
}
|
|
|
|
size_t
|
|
blobGetDataSize(const blob *b)
|
|
{
|
|
assert(b != NULL);
|
|
#ifdef CL_DEBUG
|
|
assert(b->magic == BLOBCLASS);
|
|
#endif
|
|
|
|
return b->len;
|
|
}
|
|
|
|
void blobClose(blob *b)
|
|
{
|
|
assert(b != NULL);
|
|
#ifdef CL_DEBUG
|
|
assert(b->magic == BLOBCLASS);
|
|
#endif
|
|
|
|
if (b->isClosed) {
|
|
cli_warnmsg("Attempt to close a previously closed blob\n");
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Nothing more is going to be added to this blob. If it'll save more
|
|
* than a trivial amount (say 64 bytes) of memory, shrink the allocation
|
|
*/
|
|
if ((b->size - b->len) >= 64) {
|
|
if (b->len == 0) { /* Not likely */
|
|
free(b->data);
|
|
b->data = NULL;
|
|
cli_dbgmsg("blobClose: recovered all %lu bytes\n",
|
|
(unsigned long)b->size);
|
|
b->size = 0;
|
|
} else {
|
|
unsigned char *ptr = cli_realloc(b->data, b->len);
|
|
|
|
if (ptr == NULL) {
|
|
return;
|
|
}
|
|
|
|
cli_dbgmsg("blobClose: recovered %lu bytes from %lu\n",
|
|
(unsigned long)(b->size - b->len),
|
|
(unsigned long)b->size);
|
|
b->size = b->len;
|
|
b->data = ptr;
|
|
}
|
|
}
|
|
b->isClosed = 1;
|
|
}
|
|
|
|
/*
|
|
* Returns 0 if the blobs are the same
|
|
*/
|
|
int blobcmp(const blob *b1, const blob *b2)
|
|
{
|
|
size_t s1, s2;
|
|
|
|
assert(b1 != NULL);
|
|
assert(b2 != NULL);
|
|
|
|
if (b1 == b2)
|
|
return 0;
|
|
|
|
s1 = blobGetDataSize(b1);
|
|
s2 = blobGetDataSize(b2);
|
|
|
|
if (s1 != s2)
|
|
return 1;
|
|
|
|
if ((s1 == 0) && (s2 == 0))
|
|
return 0;
|
|
|
|
return memcmp(blobGetData(b1), blobGetData(b2), s1);
|
|
}
|
|
|
|
/*
|
|
* Return clamav return code
|
|
*/
|
|
int blobGrow(blob *b, size_t len)
|
|
{
|
|
assert(b != NULL);
|
|
#ifdef CL_DEBUG
|
|
assert(b->magic == BLOBCLASS);
|
|
#endif
|
|
|
|
if (len == 0)
|
|
return CL_SUCCESS;
|
|
|
|
if (b->isClosed) {
|
|
/*
|
|
* Should be cli_dbgmsg, but I want to see them for now,
|
|
* and cli_dbgmsg doesn't support debug levels
|
|
*/
|
|
cli_warnmsg("Growing closed blob\n");
|
|
b->isClosed = 0;
|
|
}
|
|
if (b->data == NULL) {
|
|
assert(b->len == 0);
|
|
assert(b->size == 0);
|
|
|
|
b->data = cli_malloc(len);
|
|
if (b->data)
|
|
b->size = (off_t)len;
|
|
} else {
|
|
unsigned char *ptr = cli_realloc(b->data, b->size + len);
|
|
|
|
if (ptr) {
|
|
b->size += (off_t)len;
|
|
b->data = ptr;
|
|
}
|
|
}
|
|
|
|
return (b->data) ? CL_SUCCESS : CL_EMEM;
|
|
}
|
|
|
|
fileblob *
|
|
fileblobCreate(void)
|
|
{
|
|
#ifdef CL_DEBUG
|
|
fileblob *fb = (fileblob *)cli_calloc(1, sizeof(fileblob));
|
|
if (fb)
|
|
fb->b.magic = BLOBCLASS;
|
|
cli_dbgmsg("blobCreate\n");
|
|
return fb;
|
|
#else
|
|
return (fileblob *)cli_calloc(1, sizeof(fileblob));
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* Returns CL_CLEAN or CL_VIRUS. Destroys the fileblob and removes the file
|
|
* if possible
|
|
*/
|
|
int fileblobScanAndDestroy(fileblob *fb)
|
|
{
|
|
switch (fileblobScan(fb)) {
|
|
case CL_VIRUS:
|
|
fileblobDestructiveDestroy(fb);
|
|
return CL_VIRUS;
|
|
case CL_BREAK:
|
|
fileblobDestructiveDestroy(fb);
|
|
return CL_CLEAN;
|
|
default:
|
|
fileblobDestroy(fb);
|
|
return CL_CLEAN;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Destroy the fileblob, and remove the file associated with it
|
|
*/
|
|
void fileblobDestructiveDestroy(fileblob *fb)
|
|
{
|
|
if (fb->fp && fb->fullname) {
|
|
fclose(fb->fp);
|
|
cli_dbgmsg("fileblobDestructiveDestroy: %s\n", fb->fullname);
|
|
if (!fb->ctx || !fb->ctx->engine->keeptmp)
|
|
cli_unlink(fb->fullname);
|
|
free(fb->fullname);
|
|
fb->fp = NULL;
|
|
fb->fullname = NULL;
|
|
}
|
|
if (fb->b.name) {
|
|
free(fb->b.name);
|
|
fb->b.name = NULL;
|
|
}
|
|
fileblobDestroy(fb);
|
|
}
|
|
|
|
/*
|
|
* Destroy the fileblob, and remove the file associated with it if that file is
|
|
* empty
|
|
*/
|
|
void fileblobDestroy(fileblob *fb)
|
|
{
|
|
assert(fb != NULL);
|
|
#ifdef CL_DEBUG
|
|
assert(fb->b.magic == BLOBCLASS);
|
|
#endif
|
|
|
|
if (fb->b.name && fb->fp) {
|
|
fclose(fb->fp);
|
|
if (fb->fullname) {
|
|
cli_dbgmsg("fileblobDestroy: %s\n", fb->fullname);
|
|
if (!fb->isNotEmpty) {
|
|
cli_dbgmsg("fileblobDestroy: not saving empty file\n");
|
|
cli_unlink(fb->fullname);
|
|
}
|
|
}
|
|
free(fb->b.name);
|
|
|
|
assert(fb->b.data == NULL);
|
|
} else if (fb->b.data) {
|
|
free(fb->b.data);
|
|
if (fb->b.name) {
|
|
cli_errmsg("fileblobDestroy: %s not saved: report to https://github.com/Cisco-Talos/clamav/issues\n",
|
|
(fb->fullname) ? fb->fullname : fb->b.name);
|
|
free(fb->b.name);
|
|
} else
|
|
cli_errmsg("fileblobDestroy: file not saved (%lu bytes): report to https://github.com/Cisco-Talos/clamav/issues\n",
|
|
(unsigned long)fb->b.len);
|
|
}
|
|
if (fb->fullname)
|
|
free(fb->fullname);
|
|
#ifdef CL_DEBUG
|
|
fb->b.magic = INVALIDCLASS;
|
|
#endif
|
|
free(fb);
|
|
}
|
|
|
|
void fileblobPartialSet(fileblob *fb, const char *fullname, const char *arg)
|
|
{
|
|
UNUSEDPARAM(arg);
|
|
|
|
if (fb->b.name)
|
|
return;
|
|
|
|
assert(fullname != NULL);
|
|
|
|
cli_dbgmsg("fileblobPartialSet: saving to %s\n", fullname);
|
|
|
|
fb->fd = open(fullname, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY | O_EXCL, 0600);
|
|
if (fb->fd < 0) {
|
|
cli_errmsg("fileblobPartialSet: unable to create file: %s\n", fullname);
|
|
return;
|
|
}
|
|
fb->fp = fdopen(fb->fd, "wb");
|
|
|
|
if (fb->fp == NULL) {
|
|
cli_errmsg("fileblobSetFilename: fdopen failed\n");
|
|
close(fb->fd);
|
|
return;
|
|
}
|
|
blobSetFilename(&fb->b, fb->ctx ? fb->ctx->sub_tmpdir : NULL, fullname);
|
|
if (fb->b.data)
|
|
if (fileblobAddData(fb, fb->b.data, fb->b.len) == 0) {
|
|
free(fb->b.data);
|
|
fb->b.data = NULL;
|
|
fb->b.len = fb->b.size = 0;
|
|
fb->isNotEmpty = 1;
|
|
}
|
|
fb->fullname = cli_strdup(fullname);
|
|
}
|
|
|
|
void fileblobSetFilename(fileblob *fb, const char *dir, const char *filename)
|
|
{
|
|
char *fullname;
|
|
|
|
if (fb->b.name)
|
|
return;
|
|
|
|
assert(filename != NULL);
|
|
assert(dir != NULL);
|
|
|
|
blobSetFilename(&fb->b, dir, filename);
|
|
|
|
/*
|
|
* Reload the filename, it may be different from the one we've
|
|
* asked for, e.g. '/'s taken out
|
|
*/
|
|
filename = blobGetFilename(&fb->b);
|
|
|
|
assert(filename != NULL);
|
|
|
|
if (cli_gentempfd(dir, &fullname, &fb->fd) != CL_SUCCESS) return;
|
|
|
|
cli_dbgmsg("fileblobSetFilename: file %s saved to %s\n", filename, fullname);
|
|
|
|
fb->fp = fdopen(fb->fd, "wb");
|
|
|
|
if (fb->fp == NULL) {
|
|
cli_errmsg("fileblobSetFilename: fdopen failed\n");
|
|
close(fb->fd);
|
|
free(fullname);
|
|
return;
|
|
}
|
|
if (fb->b.data)
|
|
if (fileblobAddData(fb, fb->b.data, fb->b.len) == 0) {
|
|
free(fb->b.data);
|
|
fb->b.data = NULL;
|
|
fb->b.len = fb->b.size = 0;
|
|
fb->isNotEmpty = 1;
|
|
}
|
|
fb->fullname = fullname;
|
|
}
|
|
|
|
int fileblobAddData(fileblob *fb, const unsigned char *data, size_t len)
|
|
{
|
|
if (len == 0)
|
|
return 0;
|
|
|
|
assert(data != NULL);
|
|
|
|
if (fb->fp) {
|
|
#if defined(MAX_SCAN_SIZE) && (MAX_SCAN_SIZE > 0)
|
|
const cli_ctx *ctx = fb->ctx;
|
|
|
|
if (fb->isInfected) /* pretend all was written */
|
|
return 0;
|
|
if (ctx) {
|
|
int do_scan = 1;
|
|
|
|
if (cli_checklimits("fileblobAddData", ctx, fb->bytes_scanned, 0, 0) != CL_CLEAN)
|
|
do_scan = 0;
|
|
|
|
if (fb->bytes_scanned > MAX_SCAN_SIZE)
|
|
do_scan = 0;
|
|
if (do_scan) {
|
|
if (ctx->scanned)
|
|
*ctx->scanned += (unsigned long)len / CL_COUNT_PRECISION;
|
|
fb->bytes_scanned += (unsigned long)len;
|
|
|
|
if ((len > 5) && cli_updatelimits(ctx, len) == CL_CLEAN && (cli_scan_buff(data, (unsigned int)len, 0, ctx->virname, ctx->engine, CL_TYPE_BINARY_DATA, NULL) == CL_VIRUS)) {
|
|
fb->isInfected = 1;
|
|
}
|
|
}
|
|
}
|
|
#endif
|
|
|
|
if (fwrite(data, len, 1, fb->fp) != 1) {
|
|
cli_errmsg("fileblobAddData: Can't write %lu bytes to temporary file %s\n",
|
|
(unsigned long)len, fb->b.name);
|
|
return -1;
|
|
}
|
|
fb->isNotEmpty = 1;
|
|
return 0;
|
|
}
|
|
return blobAddData(&(fb->b), data, len);
|
|
}
|
|
|
|
const char *
|
|
fileblobGetFilename(const fileblob *fb)
|
|
{
|
|
return blobGetFilename(&(fb->b));
|
|
}
|
|
|
|
void fileblobSetCTX(fileblob *fb, cli_ctx *ctx)
|
|
{
|
|
fb->ctx = ctx;
|
|
}
|
|
|
|
/*
|
|
* Performs a full scan on the fileblob, returning ClamAV status:
|
|
* CL_BREAK means clean
|
|
* CL_CLEAN means unknown
|
|
* CL_VIRUS means infected
|
|
*/
|
|
cl_error_t fileblobScan(const fileblob *fb)
|
|
{
|
|
cl_error_t rc;
|
|
STATBUF sb;
|
|
|
|
if (fb->isInfected)
|
|
return CL_VIRUS;
|
|
if (fb->fp == NULL || fb->fullname == NULL) {
|
|
/* shouldn't happen, scan called before fileblobSetFilename */
|
|
cli_warnmsg("fileblobScan, fullname == NULL\n");
|
|
return CL_ENULLARG; /* there is no CL_UNKNOWN */
|
|
}
|
|
if (fb->ctx == NULL) {
|
|
/* fileblobSetCTX hasn't been called */
|
|
cli_dbgmsg("fileblobScan, ctx == NULL\n");
|
|
return CL_CLEAN; /* there is no CL_UNKNOWN */
|
|
}
|
|
|
|
fflush(fb->fp);
|
|
lseek(fb->fd, 0, SEEK_SET);
|
|
FSTAT(fb->fd, &sb);
|
|
|
|
rc = cli_matchmeta(fb->ctx, fb->b.name, sb.st_size, sb.st_size, 0, 0, 0, NULL);
|
|
if (rc != CL_SUCCESS) {
|
|
return rc;
|
|
}
|
|
|
|
rc = cli_magic_scan_desc(fb->fd, fb->fullname, fb->ctx, fb->b.name, LAYER_ATTRIBUTES_NONE);
|
|
if (rc != CL_SUCCESS) {
|
|
return rc;
|
|
}
|
|
|
|
return CL_BREAK;
|
|
}
|
|
|
|
/*
|
|
* Doesn't perform a full scan just lets the caller know if something suspicious has
|
|
* been seen yet
|
|
*/
|
|
int fileblobInfected(const fileblob *fb)
|
|
{
|
|
return fb->isInfected;
|
|
}
|
|
|
|
/*
|
|
* Different operating systems allow different characters in their filenames
|
|
* FIXME: What does QNX want? There is no #ifdef C_QNX, but if there were
|
|
* it may be best to treat it like MSDOS
|
|
*/
|
|
void sanitiseName(char *name)
|
|
{
|
|
char c;
|
|
while ((c = *name)) {
|
|
if (c != '.' && c != '_' && (c > 'z' || c < '0' || (c > '9' && c < 'A') || (c > 'Z' && c < 'a'))) {
|
|
*name = '_';
|
|
}
|
|
name++;
|
|
}
|
|
}
|