From 56019f9aca2266edc7f304d91e4e772023b7aa14 Mon Sep 17 00:00:00 2001 From: Pierre Morel Date: Tue, 25 Sep 2018 19:16:33 -0400 Subject: KVM: s390: vsie: Allow CRYCB FORMAT-2 When the guest and the host both use CRYCB FORMAT-2, we copy the guest's FORMAT-1 APCB to a FORMAT-1 shadow APCB. This patch also cleans up the shadow_crycb() function. Signed-off-by: Pierre Morel Signed-off-by: Tony Krowiak Message-Id: <20180925231641.4954-19-akrowiak@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger --- arch/s390/kvm/vsie.c | 114 ++++++++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 104 insertions(+), 10 deletions(-) (limited to 'arch/s390/kvm/vsie.c') diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c index e0e6fbfa88f4..3a932781e0b0 100644 --- a/arch/s390/kvm/vsie.c +++ b/arch/s390/kvm/vsie.c @@ -136,14 +136,81 @@ static int prepare_cpuflags(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) return 0; } -/* +/** + * setup_apcb11 - Copy the FORMAT1 APCB from the guest to the shadow CRYCB + * @vcpu: pointer to the virtual CPU + * @apcb_s: pointer to start of apcb in the shadow crycb + * @apcb_o: pointer to start of original guest apcb + * @apcb_h: pointer to start of apcb in the host + * + * Returns 0 and -EFAULT on error reading guest apcb + */ +static int setup_apcb11(struct kvm_vcpu *vcpu, unsigned long *apcb_s, + unsigned long apcb_o, + unsigned long *apcb_h) +{ + if (read_guest_real(vcpu, apcb_o, apcb_s, + sizeof(struct kvm_s390_apcb1))) + return -EFAULT; + + bitmap_and(apcb_s, apcb_s, apcb_h, sizeof(struct kvm_s390_apcb1)); + + return 0; +} + +/** + * setup_apcb - Create a shadow copy of the apcb. + * @vcpu: pointer to the virtual CPU + * @crycb_s: pointer to shadow crycb + * @crycb_o: pointer to original guest crycb + * @crycb_h: pointer to the host crycb + * @fmt_o: format of the original guest crycb. + * @fmt_h: format of the host crycb. + * + * Checks the compatibility between the guest and host crycb and calls the + * appropriate copy function. + * + * Return 0 or an error number if the guest and host crycb are incompatible. + */ +static int setup_apcb(struct kvm_vcpu *vcpu, struct kvm_s390_crypto_cb *crycb_s, + const u32 crycb_o, + struct kvm_s390_crypto_cb *crycb_h, + int fmt_o, int fmt_h) +{ + struct kvm_s390_crypto_cb *crycb; + + crycb = (struct kvm_s390_crypto_cb *) (unsigned long)crycb_o; + + switch (fmt_o) { + case CRYCB_FORMAT2: + if ((crycb_o & PAGE_MASK) != ((crycb_o + 256) & PAGE_MASK)) + return -EACCES; + if (fmt_h != CRYCB_FORMAT2) + return -EINVAL; + return setup_apcb11(vcpu, (unsigned long *)&crycb_s->apcb1, + (unsigned long) &crycb->apcb1, + (unsigned long *)&crycb_h->apcb1); + } + return -EINVAL; +} + +/** + * shadow_crycb - Create a shadow copy of the crycb block + * @vcpu: a pointer to the virtual CPU + * @vsie_page: a pointer to internal date used for the vSIE + * * Create a shadow copy of the crycb block and setup key wrapping, if * requested for guest 3 and enabled for guest 2. * - * We accept format-1 or format-2, but we treat it as a format-1 (no AP in g2), - * and we convert it into format-2 in the shadow CRYCB. + * We accept format-1 or format-2, but we convert format-1 into format-2 + * in the shadow CRYCB. + * Using format-2 enables the firmware to choose the right format when + * scheduling the SIE. * There is nothing to do for format-0. * + * This function centralize the issuing of set_validity_icpt() for all + * the subfunctions working on the crycb. + * * Returns: - 0 if shadowed or nothing to do * - > 0 if control has to be given to guest 2 */ @@ -155,24 +222,42 @@ static int shadow_crycb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) const u32 crycb_addr = crycbd_o & 0x7ffffff8U; unsigned long *b1, *b2; u8 ecb3_flags; + int apie_h; + int key_msk = test_kvm_facility(vcpu->kvm, 76); + int fmt_o = crycbd_o & CRYCB_FORMAT_MASK; + int fmt_h = vcpu->arch.sie_block->crycbd & CRYCB_FORMAT_MASK; + int ret = 0; scb_s->crycbd = 0; if (!(crycbd_o & 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)) + + apie_h = vcpu->arch.sie_block->eca & ECA_APIE; + if (!apie_h && !key_msk) return 0; - if ((crycb_addr & PAGE_MASK) != ((crycb_addr + 128) & PAGE_MASK)) - return set_validity_icpt(scb_s, 0x003CU); - else if (!crycb_addr) + if (!crycb_addr) return set_validity_icpt(scb_s, 0x0039U); + if (fmt_o == CRYCB_FORMAT1) + if ((crycb_addr & PAGE_MASK) != + ((crycb_addr + 128) & PAGE_MASK)) + return set_validity_icpt(scb_s, 0x003CU); + + if (apie_h && (scb_o->eca & ECA_APIE)) { + ret = setup_apcb(vcpu, &vsie_page->crycb, crycb_addr, + vcpu->kvm->arch.crypto.crycb, + fmt_o, fmt_h); + if (ret) + goto end; + scb_s->eca |= scb_o->eca & ECA_APIE; + } + /* 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; + goto end; /* copy only the wrapping keys */ if (read_guest_real(vcpu, crycb_addr + 72, @@ -180,7 +265,6 @@ static int shadow_crycb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) return set_validity_icpt(scb_s, 0x0035U); scb_s->ecb3 |= ecb3_flags; - scb_s->crycbd = ((__u32)(__u64) &vsie_page->crycb) | CRYCB_FORMAT2; /* xor both blocks in one run */ b1 = (unsigned long *) vsie_page->crycb.dea_wrapping_key_mask; @@ -188,6 +272,16 @@ static int shadow_crycb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) 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); +end: + switch (ret) { + case -EINVAL: + return set_validity_icpt(scb_s, 0x0020U); + case -EFAULT: + return set_validity_icpt(scb_s, 0x0035U); + case -EACCES: + return set_validity_icpt(scb_s, 0x003CU); + } + scb_s->crycbd = ((__u32)(__u64) &vsie_page->crycb) | CRYCB_FORMAT2; return 0; } -- cgit v1.2.3