[dev][virtio-rng] Introduce virtio-rng driver to seed system prng#506
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Looks great! just a few nits and this is lovely. Thanks!
| int virtio_pci_init() { | ||
| LTRACE_ENTRY; | ||
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| constexpr virtio_pci_devices devices[] = { |
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can you also add a virtio-mmio interface for this? Should be pretty easy, can test with the arm64 qemu since it can run with both mmio and PCI virtio interfaces (i think the -C flag switches to PCI from the default mmio)
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| bytes_read = virtio_rng_read(&seed, sizeof(seed)); | ||
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| if (bytes_read == sizeof(seed)) { | ||
| srand(seed); |
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reminds me we should implement a better system RNG
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I would be glad to help improve the system rng.
If there is anything specific you need help with or any direction you'd like me to explore, just let me know!
Introduces a new virtio-rng driver to fetch entropy from the host in virtualized environments. Additionally, an early boot hook (LK_INIT_LEVEL_TARGET + 1) is added to automatically seed the system's PRNG via srand() when the device is initialized. Signed-off-by: Kuan-Wei Chiu <visitorckw@gmail.com>
Add initialization dispatch for the virtio-rng device. This registers the transitional (0x1005) and non-transitional (0x1044) virtio-rng device IDs to the virtio PCI bus driver, allowing the bus to probe and initialize the device when discovered. Signed-off-by: Kuan-Wei Chiu <visitorckw@gmail.com>
Add initialization dispatch for the virtio-rng device on the MMIO. This registers the virtio-rng subsystem device ID (4) to the virtio MMIO driver, allowing platforms that default to MMIO to probe and initialize the hardware entropy source. Signed-off-by: Kuan-Wei Chiu <visitorckw@gmail.com>
Add dev/virtio/rng to the module dependencies for the qemu-virt-arm platform. This allows the system to automatically fetch hardware entropy and seed the PRNG during the early boot process. Signed-off-by: Kuan-Wei Chiu <visitorckw@gmail.com>
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Introduces a new virtio-rng driver to fetch hardware entropy from the host in virtualized environments.
Additionally, an early boot hook is implemented to automatically fetch entropy and seed the system's prng via srand() after the device is initialized.