Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit bbeaa58b authored by David Hildenbrand's avatar David Hildenbrand Committed by Christian Borntraeger
Browse files

KVM: s390: vsie: support aes dea wrapping keys 



As soon as message-security-assist extension 3 is enabled for guest 2,
we have to allow key wrapping for guest 3.

Acked-by: default avatarChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: default avatarDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: default avatarChristian Borntraeger <borntraeger@de.ibm.com>
parent 66b630d5

arch/s390/kvm/vsie.c

+55 −1
Original line number Diff line number Diff line
@@ -28,7 +28,8 @@ struct vsie_page { 
	struct kvm_s390_sie_block *scb_o;	/* 0x0200 */

	/* the shadow gmap in use by the vsie_page */

	struct gmap *gmap;			/* 0x0208 */

	__u8 reserved[0x0800 - 0x0210];		/* 0x0210 */

	__u8 reserved[0x0700 - 0x0210];		/* 0x0210 */

	struct kvm_s390_crypto_cb crycb;	/* 0x0700 */

	__u8 fac[S390_ARCH_FAC_LIST_SIZE_BYTE];	/* 0x0800 */

} __packed;
@@ -111,6 +112,58 @@ static int prepare_cpuflags(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) 
	return 0;

}



/*

 * Create a shadow copy of the crycb block and setup key wrapping, if

 * requested for guest 3 and enabled for guest 2.

 *

 * We only accept format-1 (no AP in g2), but convert it into format-2

 * There is nothing to do for format-0.

 *

 * Returns: - 0 if shadowed or nothing to do

 *          - > 0 if control has to be given to guest 2

 */

static int shadow_crycb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)

{

	struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;

	struct kvm_s390_sie_block *scb_o = vsie_page->scb_o;

	u32 crycb_addr = scb_o->crycbd & 0x7ffffff8U;

	unsigned long *b1, *b2;

	u8 ecb3_flags;



	scb_s->crycbd = 0;

	if (!(scb_o->crycbd & vcpu->arch.sie_block->crycbd & CRYCB_FORMAT1))

		return 0;

	/* format-1 is supported with message-security-assist extension 3 */

	if (!test_kvm_facility(vcpu->kvm, 76))

		return 0;

	/* we may only allow it if enabled for guest 2 */

	ecb3_flags = scb_o->ecb3 & vcpu->arch.sie_block->ecb3 &

		     (ECB3_AES | ECB3_DEA);

	if (!ecb3_flags)

		return 0;



	if ((crycb_addr & PAGE_MASK) != ((crycb_addr + 128) & PAGE_MASK))

		return set_validity_icpt(scb_s, 0x003CU);

	else if (!crycb_addr)

		return set_validity_icpt(scb_s, 0x0039U);



	/* copy only the wrapping keys */

	if (read_guest_real(vcpu, crycb_addr + 72, &vsie_page->crycb, 56))

		return set_validity_icpt(scb_s, 0x0035U);



	scb_s->ecb3 |= ecb3_flags;

	scb_s->crycbd = ((__u32)(__u64) &vsie_page->crycb) | CRYCB_FORMAT1 |

			CRYCB_FORMAT2;



	/* xor both blocks in one run */

	b1 = (unsigned long *) vsie_page->crycb.dea_wrapping_key_mask;

	b2 = (unsigned long *)

			    vcpu->kvm->arch.crypto.crycb->dea_wrapping_key_mask;

	/* as 56%8 == 0, bitmap_xor won't overwrite any data */

	bitmap_xor(b1, b1, b2, BITS_PER_BYTE * 56);

	return 0;

}



/* shadow (round up/down) the ibc to avoid validity icpt */

static void prepare_ibc(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)

{
@@ -248,6 +301,7 @@ static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) 
		scb_s->ecb |= scb_o->ecb & 0x02U;



	prepare_ibc(vcpu, vsie_page);

	rc = shadow_crycb(vcpu, vsie_page);

out:

	if (rc)

		unshadow_scb(vcpu, vsie_page);