This patch relocates the real-path check from clamdscan and clamonacc
to clamd. While clamonacc is unlikely to send directories or symlinks
to be scanned, clamdscan may send directories. Real-path checks have
to be performed on the files, not the directories -- both because the
directories may contain symlinks and because the cli_realpath()
function wasn't written to support directories on Windows.
Add missing ping_clamd() declaration in client.h
Fix check for ping option to first check if ping option is NULL before
strdup'ing and checking if the alloc failed.
Fix format string for uint64_t print.
Correctly assign name pointer to stack buffer in cpio parser.
Remove vestigial variables from insert_list() function matcher-ac.c,
left over from before the load-time optimizations completely
restructured everything.
Silence warnings about unused parameters in progress bar callback
function.
Removed all autotools generates files. Autotools (autoconf, automake,
libtool, pkg-config, m4) will be required from now on for builds from
git clones.
Added autogen.sh to be run before ./configure.
Significant update to main .gitignore file.
Removed extraneous .gitignore files. A Git repository only needs one
.gitignore file.
A malicious user could replace a scan target's directory with a symlink
to another path to trick clamscan, clamdscan, or clamonacc into removing
or moving a different file (eg. a critical system file). The issue would
affect users that use the `--move` or `--remove` options for clamscan,
clamdscan, and clamonacc.
This patch gets the real path for the scan target before the scan,
and if the file alerts and the --move or --remove quarantine features
are used, it mitigates the symlink attack by traversing the path one
directory at a time until reaching the leaf directory where the scan
target file resides before unlinking (or renaming) the file directly.
This commit applies a similar tactic used in the previous commit for
Windows builds, using the Win32 Native API to traverse a path and delete
or move files by handle rather than by file path.
I had some trouble using SetFileInformationByHandle to rename a file by
handle, so for Windows instead it will copy the file to the new location
and then use the safe unlink technique to remove the old file. If the
symlink attack occurs, the unlink will fail, and the system will not be
damaged.
For more information about AV quarantine attacks using links, see the
[RACK911 Lab's report](https://www.rack911labs.com/research/exploiting-almost-every-antivirus-software)
This addresses an issue introduced early in 0.103 development when the
start/end timestamps were added to the scan summary.
The localtime function equivalent on Windows has the argument order reversed.
New features added to freshclam:
- Update signature definitions over HTTPS.
- Support for HTTP protocol v1.1 (formerly v1.0).
- New libfreshclam library with an all new API and versioning separate from libclamav (v2.0.0). This library is now build and installed alongside libclamav as a hard dependency of freshclam.
- The ability to opt-in and opt-out of standard and optional official ClamAV databases (ExtraDatabase, ExcludeDatabase)
- The option to specify the protocol and port number of official and private mirror servers.
- Support for additional types of proxy servers beyond plain HTTP (SOCKS 4, SOCKS 5).
Features removed from freshclam:
- Mirror management (mirrors.dat) file. This feature is no longer needed as official signature databases are distributed using a paid content delivery network (Cloudflare).
This commit also adds the following features for Windows users:
- The clamsubmit tool.
- The json-c library dependency, which will enable the --gen-json option in clamscan.
- Third party libraries under the win32/3rdparty directory have been removed. Developers will need to build the libraries separately from ClamAV and provide the headers and lib/dll library files the same way they do for OpenSSL. This includes libxml2, pthread-win32, bzip2, zlib, pcre2 as well as new dependencies: curl, json-c. Developers are encouraged to use the build tool Mussels to simplify this task.
Micah Snyder (micasnyd)