From: Jean-Philippe Brucker <[email protected]> Add a Rom notifier to keep track of binary blobs loaded in Realm memory. That way we can deterministically calculate the Realm Initial Measurement (RIM).
Signed-off-by: Jean-Philippe Brucker <[email protected]> Signed-off-by: Mathieu Poirier <[email protected]> --- target/arm/kvm-rme.c | 52 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 52 insertions(+) diff --git a/target/arm/kvm-rme.c b/target/arm/kvm-rme.c index 5d6814fcf9e5..10bca9a944ba 100644 --- a/target/arm/kvm-rme.c +++ b/target/arm/kvm-rme.c @@ -10,6 +10,7 @@ #include "hw/core/boards.h" #include "hw/core/cpu.h" +#include "hw/core/loader.h" #include "kvm_arm.h" #include "migration/blocker.h" #include "qapi/error.h" @@ -22,8 +23,18 @@ #define TYPE_RME_GUEST "rme-guest" OBJECT_DECLARE_SIMPLE_TYPE(RmeGuest, RME_GUEST) +#define RME_PAGE_SIZE qemu_real_host_page_size() + +typedef struct { + hwaddr base; + hwaddr size; + AddressSpace *as; +} RmeRamRegion; + struct RmeGuest { ConfidentialGuestSupport parent_obj; + Notifier rom_load_notifier; + GSList *ram_regions; }; OBJECT_DEFINE_SIMPLE_TYPE_WITH_INTERFACES(RmeGuest, rme_guest, RME_GUEST, @@ -41,6 +52,44 @@ static void rme_vm_state_change(void *opaque, bool running, RunState state) kvm_mark_guest_state_protected(); } +static gint rme_compare_ram_regions(gconstpointer a, gconstpointer b) +{ + const RmeRamRegion *ra = a; + const RmeRamRegion *rb = b; + + g_assert(ra->base != rb->base); + return ra->base < rb->base ? -1 : 1; +} + +static void rme_rom_load_notify(Notifier *notifier, void *data) +{ + RmeRamRegion *region; + RomLoaderNotifyData *rom = data; + + if (rom->addr == -1) { + /* + * These blobs (ACPI tables) are not loaded into guest RAM at reset. + * Instead the firmware will load them via fw_cfg and measure them + * itself. + */ + return; + } + + region = g_new0(RmeRamRegion, 1); + region->base = rom->addr; + region->size = rom->len; + region->as = rom->as; + + /* + * The Realm Initial Measurement (RIM) depends on the order in which we + * initialize and populate the RAM regions. To help a verifier + * independently calculate the RIM, sort regions by GPA. + */ + rme_guest->ram_regions = g_slist_insert_sorted(rme_guest->ram_regions, + region, + rme_compare_ram_regions); +} + static int kvm_arm_rme_init(ConfidentialGuestSupport *cgs, Error **errp) { KVMState *s = KVM_STATE(current_accel()); @@ -58,6 +107,9 @@ static int kvm_arm_rme_init(ConfidentialGuestSupport *cgs, Error **errp) error_setg(&rme_mig_blocker, "RME: migration is not implemented"); migrate_add_blocker(&rme_mig_blocker, &error_fatal); + rme_guest->rom_load_notifier.notify = rme_rom_load_notify; + rom_add_load_notifier(&rme_guest->rom_load_notifier); + /* * The realm activation is done last, when the VM starts, after all images * have been loaded and all vcpus finalized. -- 2.43.0
