diff options
| -rw-r--r-- | Documentation/virt/kvm/amd-memory-encryption.rst | 29 | ||||
| -rw-r--r-- | arch/x86/kvm/svm/sev.c | 81 | ||||
| -rw-r--r-- | include/uapi/linux/kvm.h | 9 |
3 files changed, 119 insertions, 0 deletions
diff --git a/Documentation/virt/kvm/amd-memory-encryption.rst b/Documentation/virt/kvm/amd-memory-encryption.rst index c36a12975763..86c9b36f4a57 100644 --- a/Documentation/virt/kvm/amd-memory-encryption.rst +++ b/Documentation/virt/kvm/amd-memory-encryption.rst @@ -365,6 +365,35 @@ migration can restart with a new target later. Returns: 0 on success, -negative on error +15. KVM_SEV_RECEIVE_START +------------------------ + +The KVM_SEV_RECEIVE_START command is used for creating the memory encryption +context for an incoming SEV guest. To create the encryption context, the user must +provide a guest policy, the platform public Diffie-Hellman (PDH) key and session +information. + +Parameters: struct kvm_sev_receive_start (in/out) + +Returns: 0 on success, -negative on error + +:: + + struct kvm_sev_receive_start { + __u32 handle; /* if zero then firmware creates a new handle */ + __u32 policy; /* guest's policy */ + + __u64 pdh_uaddr; /* userspace address pointing to the PDH key */ + __u32 pdh_len; + + __u64 session_uaddr; /* userspace address which points to the guest session information */ + __u32 session_len; + }; + +On success, the 'handle' field contains a new handle and on error, a negative value. + +For more details, see SEV spec Section 6.12. + References ========== diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index 552f47787143..3e5064c69124 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -1397,6 +1397,84 @@ static int sev_send_cancel(struct kvm *kvm, struct kvm_sev_cmd *argp) return ret; } +static int sev_receive_start(struct kvm *kvm, struct kvm_sev_cmd *argp) +{ + struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; + struct sev_data_receive_start *start; + struct kvm_sev_receive_start params; + int *error = &argp->error; + void *session_data; + void *pdh_data; + int ret; + + if (!sev_guest(kvm)) + return -ENOTTY; + + /* Get parameter from the userspace */ + if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, + sizeof(struct kvm_sev_receive_start))) + return -EFAULT; + + /* some sanity checks */ + if (!params.pdh_uaddr || !params.pdh_len || + !params.session_uaddr || !params.session_len) + return -EINVAL; + + pdh_data = psp_copy_user_blob(params.pdh_uaddr, params.pdh_len); + if (IS_ERR(pdh_data)) + return PTR_ERR(pdh_data); + + session_data = psp_copy_user_blob(params.session_uaddr, + params.session_len); + if (IS_ERR(session_data)) { + ret = PTR_ERR(session_data); + goto e_free_pdh; + } + + ret = -ENOMEM; + start = kzalloc(sizeof(*start), GFP_KERNEL); + if (!start) + goto e_free_session; + + start->handle = params.handle; + start->policy = params.policy; + start->pdh_cert_address = __psp_pa(pdh_data); + start->pdh_cert_len = params.pdh_len; + start->session_address = __psp_pa(session_data); + start->session_len = params.session_len; + + /* create memory encryption context */ + ret = __sev_issue_cmd(argp->sev_fd, SEV_CMD_RECEIVE_START, start, + error); + if (ret) + goto e_free; + + /* Bind ASID to this guest */ + ret = sev_bind_asid(kvm, start->handle, error); + if (ret) + goto e_free; + + params.handle = start->handle; + if (copy_to_user((void __user *)(uintptr_t)argp->data, + ¶ms, sizeof(struct kvm_sev_receive_start))) { + ret = -EFAULT; + sev_unbind_asid(kvm, start->handle); + goto e_free; + } + + sev->handle = start->handle; + sev->fd = argp->sev_fd; + +e_free: + kfree(start); +e_free_session: + kfree(session_data); +e_free_pdh: + kfree(pdh_data); + + return ret; +} + int svm_mem_enc_op(struct kvm *kvm, void __user *argp) { struct kvm_sev_cmd sev_cmd; @@ -1471,6 +1549,9 @@ int svm_mem_enc_op(struct kvm *kvm, void __user *argp) case KVM_SEV_SEND_CANCEL: r = sev_send_cancel(kvm, &sev_cmd); break; + case KVM_SEV_RECEIVE_START: + r = sev_receive_start(kvm, &sev_cmd); + break; default: r = -EINVAL; goto out; diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 5d1adeb13739..248d1d266bc3 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -1755,6 +1755,15 @@ struct kvm_sev_send_update_data { __u32 trans_len; }; +struct kvm_sev_receive_start { + __u32 handle; + __u32 policy; + __u64 pdh_uaddr; + __u32 pdh_len; + __u64 session_uaddr; + __u32 session_len; +}; + #define KVM_DEV_ASSIGN_ENABLE_IOMMU (1 << 0) #define KVM_DEV_ASSIGN_PCI_2_3 (1 << 1) #define KVM_DEV_ASSIGN_MASK_INTX (1 << 2) |