diff options
Diffstat (limited to 'target/i386/sev.c')
| -rw-r--r-- | target/i386/sev.c | 178 |
1 files changed, 176 insertions, 2 deletions
diff --git a/target/i386/sev.c b/target/i386/sev.c index 11c9a3cc21..0f414df02f 100644 --- a/target/i386/sev.c +++ b/target/i386/sev.c @@ -22,6 +22,7 @@ #include "qom/object_interfaces.h" #include "qemu/base64.h" #include "qemu/module.h" +#include "qemu/uuid.h" #include "sysemu/kvm.h" #include "sev_i386.h" #include "sysemu/sysemu.h" @@ -32,6 +33,7 @@ #include "exec/address-spaces.h" #include "monitor/monitor.h" #include "exec/confidential-guest-support.h" +#include "hw/i386/pc.h" #define TYPE_SEV_GUEST "sev-guest" OBJECT_DECLARE_SIMPLE_TYPE(SevGuestState, SEV_GUEST) @@ -67,11 +69,21 @@ struct SevGuestState { int sev_fd; SevState state; gchar *measurement; + + uint32_t reset_cs; + uint32_t reset_ip; + bool reset_data_valid; }; #define DEFAULT_GUEST_POLICY 0x1 /* disable debug */ #define DEFAULT_SEV_DEVICE "/dev/sev" +#define SEV_INFO_BLOCK_GUID "00f771de-1a7e-4fcb-890e-68c77e2fb44e" +typedef struct __attribute__((__packed__)) SevInfoBlock { + /* SEV-ES Reset Vector Address */ + uint32_t reset_addr; +} SevInfoBlock; + static SevGuestState *sev_guest; static Error *sev_mig_blocker; @@ -341,6 +353,12 @@ sev_enabled(void) return !!sev_guest; } +bool +sev_es_enabled(void) +{ + return sev_enabled() && (sev_guest->policy & SEV_POLICY_ES); +} + uint64_t sev_get_me_mask(void) { @@ -561,6 +579,20 @@ sev_launch_update_data(SevGuestState *sev, uint8_t *addr, uint64_t len) return ret; } +static int +sev_launch_update_vmsa(SevGuestState *sev) +{ + int ret, fw_error; + + ret = sev_ioctl(sev->sev_fd, KVM_SEV_LAUNCH_UPDATE_VMSA, NULL, &fw_error); + if (ret) { + error_report("%s: LAUNCH_UPDATE_VMSA ret=%d fw_error=%d '%s'", + __func__, ret, fw_error, fw_error_to_str(fw_error)); + } + + return ret; +} + static void sev_launch_get_measure(Notifier *notifier, void *unused) { @@ -573,6 +605,14 @@ sev_launch_get_measure(Notifier *notifier, void *unused) return; } + if (sev_es_enabled()) { + /* measure all the VM save areas before getting launch_measure */ + ret = sev_launch_update_vmsa(sev); + if (ret) { + exit(1); + } + } + measurement = g_new0(struct kvm_sev_launch_measure, 1); /* query the measurement blob length */ @@ -667,7 +707,7 @@ int sev_kvm_init(ConfidentialGuestSupport *cgs, Error **errp) SevGuestState *sev = (SevGuestState *)object_dynamic_cast(OBJECT(cgs), TYPE_SEV_GUEST); char *devname; - int ret, fw_error; + int ret, fw_error, cmd; uint32_t ebx; uint32_t host_cbitpos; struct sev_user_data_status status = {}; @@ -724,8 +764,26 @@ int sev_kvm_init(ConfidentialGuestSupport *cgs, Error **errp) sev->api_major = status.api_major; sev->api_minor = status.api_minor; + if (sev_es_enabled()) { + if (!kvm_kernel_irqchip_allowed()) { + error_report("%s: SEV-ES guests require in-kernel irqchip support", + __func__); + goto err; + } + + if (!(status.flags & SEV_STATUS_FLAGS_CONFIG_ES)) { + error_report("%s: guest policy requires SEV-ES, but " + "host SEV-ES support unavailable", + __func__); + goto err; + } + cmd = KVM_SEV_ES_INIT; + } else { + cmd = KVM_SEV_INIT; + } + trace_kvm_sev_init(); - ret = sev_ioctl(sev->sev_fd, KVM_SEV_INIT, NULL, &fw_error); + ret = sev_ioctl(sev->sev_fd, cmd, NULL, &fw_error); if (ret) { error_setg(errp, "%s: failed to initialize ret=%d fw_error=%d '%s'", __func__, ret, fw_error, fw_error_to_str(fw_error)); @@ -833,6 +891,122 @@ int sev_inject_launch_secret(const char *packet_hdr, const char *secret, return 0; } +static int +sev_es_parse_reset_block(SevInfoBlock *info, uint32_t *addr) +{ + if (!info->reset_addr) { + error_report("SEV-ES reset address is zero"); + return 1; + } + + *addr = info->reset_addr; + + return 0; +} + +static int +sev_es_find_reset_vector(void *flash_ptr, uint64_t flash_size, + uint32_t *addr) +{ + QemuUUID info_guid, *guid; + SevInfoBlock *info; + uint8_t *data; + uint16_t *len; + + /* + * Initialize the address to zero. An address of zero with a successful + * return code indicates that SEV-ES is not active. + */ + *addr = 0; + + /* + * Extract the AP reset vector for SEV-ES guests by locating the SEV GUID. + * The SEV GUID is located on its own (original implementation) or within + * the Firmware GUID Table (new implementation), either of which are + * located 32 bytes from the end of the flash. + * + * Check the Firmware GUID Table first. + */ + if (pc_system_ovmf_table_find(SEV_INFO_BLOCK_GUID, &data, NULL)) { + return sev_es_parse_reset_block((SevInfoBlock *)data, addr); + } + + /* + * SEV info block not found in the Firmware GUID Table (or there isn't + * a Firmware GUID Table), fall back to the original implementation. + */ + data = flash_ptr + flash_size - 0x20; + + qemu_uuid_parse(SEV_INFO_BLOCK_GUID, &info_guid); + info_guid = qemu_uuid_bswap(info_guid); /* GUIDs are LE */ + + guid = (QemuUUID *)(data - sizeof(info_guid)); + if (!qemu_uuid_is_equal(guid, &info_guid)) { + error_report("SEV information block/Firmware GUID Table block not found in pflash rom"); + return 1; + } + + len = (uint16_t *)((uint8_t *)guid - sizeof(*len)); + info = (SevInfoBlock *)(data - le16_to_cpu(*len)); + + return sev_es_parse_reset_block(info, addr); +} + +void sev_es_set_reset_vector(CPUState *cpu) +{ + X86CPU *x86; + CPUX86State *env; + + /* Only update if we have valid reset information */ + if (!sev_guest || !sev_guest->reset_data_valid) { + return; + } + + /* Do not update the BSP reset state */ + if (cpu->cpu_index == 0) { + return; + } + + x86 = X86_CPU(cpu); + env = &x86->env; + + cpu_x86_load_seg_cache(env, R_CS, 0xf000, sev_guest->reset_cs, 0xffff, + DESC_P_MASK | DESC_S_MASK | DESC_CS_MASK | + DESC_R_MASK | DESC_A_MASK); + + env->eip = sev_guest->reset_ip; +} + +int sev_es_save_reset_vector(void *flash_ptr, uint64_t flash_size) +{ + CPUState *cpu; + uint32_t addr; + int ret; + + if (!sev_es_enabled()) { + return 0; + } + + addr = 0; + ret = sev_es_find_reset_vector(flash_ptr, flash_size, + &addr); + if (ret) { + return ret; + } + + if (addr) { + sev_guest->reset_cs = addr & 0xffff0000; + sev_guest->reset_ip = addr & 0x0000ffff; + sev_guest->reset_data_valid = true; + + CPU_FOREACH(cpu) { + sev_es_set_reset_vector(cpu); + } + } + + return 0; +} + static void sev_register_types(void) { |