3 ms·
A rootkit can be anywhere on the PCIe bus. Just for example, you are using OpenBSD and full disk encryption and you think you are safe? What if the firmware on
by jakobdabo 10y ago
A rootkit can be anywhere on the PCIe bus.
Just for example, you are using OpenBSD and full disk encryption and you think you are safe? What if the firmware on your NIC can be altered to scan your RAM (using DMA) and send the interesting data (big prime numbers, passwords, etc.) home? What if firmware on your keyboard can be modified (or pre-programmed in factory) to record the last x thousands of keypresses (which will include your boot disk password) on its own flash memory which can be later extracted? There are so many attack vectors.
- simcop2387 10y agoThis is one reason I do like the features of newer CPUs like amds Zen line with memory encryption. Combined with the iommu/vt-d features it should be possible to isolate a hardware device from reading all ram, just the buffers that it should be able to access. Thatll come with a performance hit (based on current hardware being used for VM gaming, maybe about 10%ish at worst) but it would be acceptable for security if that level of attack is something you want to guard against.
- yrro 10y agoAren't IOMMUs supposed to be able to prevent e.g., a NIC from having access to any RAM other than what the OS grants it?