Ensure that the path to a dump image specified in the NGDump meta file
of a dump device points to a valid location within the dump device.
Especially, disallow escaping from a dump device with a dump image path
using references to '..' or symbolic links pointing outside of the dump
device.
Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Replace the popen() call to the external tool sha256sum with OpenSSL's
SHA256 digest algorithm to compute the checksum of a dump image
to improve security of NGDump.
The call to popen() is inherently insecure because a malicious user
controlling a dump device could manipulate the latter and let the user
applying zgetdump to the dump device execute arbitrary shell code.
Furthermore, getting rid of process and shell spawning performed by
popen() shall improve performance of calculation of dump image
checksums.
Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Reviewed-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
The name of a private NGDump function does not require to have a unique
prefix to avoid naming conflicts with public functions of other C modules.
Furthermore, be consistent with private NGDump functions not having
the prefix 'ngdump_'.
Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Reviewed-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
When checking CDL formatted DASD for installed dump-tool (zgetdump -d),
we might stumble upon an 'empty' boot record pointer in the volume label
filled with bytes of 0x40 (EBCDIC spaces). This leads to the following
seek error reported:
# zgetdump -d /dev/dasdb
zgetdump: Could not seek "/dev/dasdb" (Invalid argument)
Check for empty boot record and return proper error code by
ngdump_get_eckd_part_num() in order to end up with a regular
"No dump tool found" message.
Fixes: f3bcd94524 ("zdump: Add zgetdump -d support for ECKD ldipl-dump")
Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Reviewed-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Make ngdump_get_part_path() public in order for unit-tests to access it.
Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
This commit introduces a new module containing various helpers for
NGDump stand-alone dump. The purpose of these helpers is to facilitate
the implementation of DT and DFI interfaces for NGDump, share code
between both, reduce duplication and enable unit testing later on.
Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
