/*
* Copyright (C) 2013-2019 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 "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;
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);
} 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);
} 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;
}
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://bugzilla.clamav.net\n",
(fb->fullname) ? fb->fullname : fb->b.name);
free(fb->b.name);
} else
cli_errmsg("fileblobDestroy: file not saved (%lu bytes): report to https://bugzilla.clamav.net\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->engine->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_scanbuff(data, (unsigned int)len, 0, ctx->virname, ctx->engine, CL_TYPE_BINARY_DATA, NULL) == CL_VIRUS)) {
cli_dbgmsg("fileblobAddData: found %s\n", cli_get_last_virus_str(ctx->virname));
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
*/
int fileblobScan(const fileblob *fb)
{
int rc;
cli_ctx *ctx = fb->ctx;
STATBUF sb;
int virus_found = 0;
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);
if (cli_matchmeta(fb->ctx, fb->b.name, sb.st_size, sb.st_size, 0, 0, 0, NULL) == CL_VIRUS) {
if (!SCAN_ALLMATCHES)
return CL_VIRUS;
virus_found = 1;
}
rc = cli_magic_scandesc(fb->fd, fb->fullname, fb->ctx);
if (rc == CL_VIRUS || virus_found != 0) {
cli_dbgmsg("%s is infected\n", fb->fullname);
return CL_VIRUS;
}
cli_dbgmsg("%s is clean\n", fb->fullname);
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++;
}
}