The Realm Personalization Value (RPV) is provided by the user to distinguish Realms that have the same initial measurement.
The user provides a 512-bit hexadecimal number. Signed-off-by: Jean-Philippe Brucker <jean-phili...@linaro.org> --- qapi/qom.json | 5 ++- target/arm/kvm-rme.c | 72 +++++++++++++++++++++++++++++++++++++++++++- 2 files changed, 75 insertions(+), 2 deletions(-) diff --git a/qapi/qom.json b/qapi/qom.json index 87fe7c31fe..a012281628 100644 --- a/qapi/qom.json +++ b/qapi/qom.json @@ -862,10 +862,13 @@ # # @measurement-algo: Realm measurement algorithm (default: RMM default) # +# @personalization-value: Realm personalization value (default: 0) +# # Since: FIXME ## { 'struct': 'RmeGuestProperties', - 'data': { '*measurement-algo': 'str' } } + 'data': { '*measurement-algo': 'str', + '*personalization-value': 'str' } } ## # @ObjectType: diff --git a/target/arm/kvm-rme.c b/target/arm/kvm-rme.c index 3929b941ae..e974c27e5c 100644 --- a/target/arm/kvm-rme.c +++ b/target/arm/kvm-rme.c @@ -22,13 +22,14 @@ OBJECT_DECLARE_SIMPLE_TYPE(RmeGuest, RME_GUEST) #define RME_PAGE_SIZE qemu_real_host_page_size() -#define RME_MAX_CFG 1 +#define RME_MAX_CFG 2 typedef struct RmeGuest RmeGuest; struct RmeGuest { ConfidentialGuestSupport parent_obj; char *measurement_algo; + char *personalization_value; }; struct RmeImage { @@ -65,6 +66,45 @@ static int rme_create_rd(RmeGuest *guest, Error **errp) return ret; } +static int rme_parse_rpv(uint8_t *out, const char *in, Error **errp) +{ + int ret; + size_t in_len = strlen(in); + + /* Two chars per byte */ + if (in_len > KVM_CAP_ARM_RME_RPV_SIZE * 2) { + error_setg(errp, "Realm Personalization Value is too large"); + return -E2BIG; + } + + /* + * Parse as big-endian hexadecimal number (most significant byte on the + * left), store little-endian, zero-padded on the right. + */ + while (in_len) { + /* + * Do the lower nibble first to catch invalid inputs such as '2z', and + * to handle the last char. + */ + in_len--; + ret = sscanf(in + in_len, "%1hhx", out); + if (ret != 1) { + error_setg(errp, "Invalid Realm Personalization Value"); + return -EINVAL; + } + if (!in_len) { + break; + } + in_len--; + ret = sscanf(in + in_len, "%2hhx", out++); + if (ret != 1) { + error_setg(errp, "Invalid Realm Personalization Value"); + return -EINVAL; + } + } + return 0; +} + static int rme_configure_one(RmeGuest *guest, uint32_t cfg, Error **errp) { int ret; @@ -87,6 +127,16 @@ static int rme_configure_one(RmeGuest *guest, uint32_t cfg, Error **errp) } cfg_str = "hash algorithm"; break; + case KVM_CAP_ARM_RME_CFG_RPV: + if (!guest->personalization_value) { + return 0; + } + ret = rme_parse_rpv(args.rpv, guest->personalization_value, errp); + if (ret) { + return ret; + } + cfg_str = "personalization value"; + break; default: g_assert_not_reached(); } @@ -281,6 +331,21 @@ static void rme_set_measurement_algo(Object *obj, const char *value, guest->measurement_algo = g_strdup(value); } +static char *rme_get_rpv(Object *obj, Error **errp) +{ + RmeGuest *guest = RME_GUEST(obj); + + return g_strdup(guest->personalization_value); +} + +static void rme_set_rpv(Object *obj, const char *value, Error **errp) +{ + RmeGuest *guest = RME_GUEST(obj); + + g_free(guest->personalization_value); + guest->personalization_value = g_strdup(value); +} + static void rme_guest_class_init(ObjectClass *oc, void *data) { object_class_property_add_str(oc, "measurement-algo", @@ -288,6 +353,11 @@ static void rme_guest_class_init(ObjectClass *oc, void *data) rme_set_measurement_algo); object_class_property_set_description(oc, "measurement-algo", "Realm measurement algorithm ('sha256', 'sha512')"); + + object_class_property_add_str(oc, "personalization-value", rme_get_rpv, + rme_set_rpv); + object_class_property_set_description(oc, "personalization-value", + "Realm personalization value (512-bit hexadecimal number)"); } static const TypeInfo rme_guest_info = { -- 2.39.0