diff options
Diffstat (limited to 'drivers/virt')
-rw-r--r-- | drivers/virt/coco/sev-guest/sev-guest.c | 84 |
1 files changed, 54 insertions, 30 deletions
diff --git a/drivers/virt/coco/sev-guest/sev-guest.c b/drivers/virt/coco/sev-guest/sev-guest.c index a33daff516ed..2a1b542168b1 100644 --- a/drivers/virt/coco/sev-guest/sev-guest.c +++ b/drivers/virt/coco/sev-guest/sev-guest.c @@ -177,7 +177,7 @@ static struct aesgcm_ctx *snp_init_crypto(u8 *key, size_t keylen) return ctx; } -static int verify_and_dec_payload(struct snp_guest_dev *snp_dev, void *payload, u32 sz) +static int verify_and_dec_payload(struct snp_guest_dev *snp_dev, struct snp_guest_req *req) { struct snp_guest_msg *resp_msg = &snp_dev->secret_response; struct snp_guest_msg *req_msg = &snp_dev->secret_request; @@ -206,20 +206,19 @@ static int verify_and_dec_payload(struct snp_guest_dev *snp_dev, void *payload, * If the message size is greater than our buffer length then return * an error. */ - if (unlikely((resp_msg_hdr->msg_sz + ctx->authsize) > sz)) + if (unlikely((resp_msg_hdr->msg_sz + ctx->authsize) > req->resp_sz)) return -EBADMSG; /* Decrypt the payload */ memcpy(iv, &resp_msg_hdr->msg_seqno, min(sizeof(iv), sizeof(resp_msg_hdr->msg_seqno))); - if (!aesgcm_decrypt(ctx, payload, resp_msg->payload, resp_msg_hdr->msg_sz, + if (!aesgcm_decrypt(ctx, req->resp_buf, resp_msg->payload, resp_msg_hdr->msg_sz, &resp_msg_hdr->algo, AAD_LEN, iv, resp_msg_hdr->authtag)) return -EBADMSG; return 0; } -static int enc_payload(struct snp_guest_dev *snp_dev, u64 seqno, int version, u8 type, - void *payload, size_t sz) +static int enc_payload(struct snp_guest_dev *snp_dev, u64 seqno, struct snp_guest_req *req) { struct snp_guest_msg *msg = &snp_dev->secret_request; struct snp_guest_msg_hdr *hdr = &msg->hdr; @@ -231,11 +230,11 @@ static int enc_payload(struct snp_guest_dev *snp_dev, u64 seqno, int version, u8 hdr->algo = SNP_AEAD_AES_256_GCM; hdr->hdr_version = MSG_HDR_VER; hdr->hdr_sz = sizeof(*hdr); - hdr->msg_type = type; - hdr->msg_version = version; + hdr->msg_type = req->msg_type; + hdr->msg_version = req->msg_version; hdr->msg_seqno = seqno; - hdr->msg_vmpck = vmpck_id; - hdr->msg_sz = sz; + hdr->msg_vmpck = req->vmpck_id; + hdr->msg_sz = req->req_sz; /* Verify the sequence number is non-zero */ if (!hdr->msg_seqno) @@ -244,17 +243,17 @@ static int enc_payload(struct snp_guest_dev *snp_dev, u64 seqno, int version, u8 pr_debug("request [seqno %lld type %d version %d sz %d]\n", hdr->msg_seqno, hdr->msg_type, hdr->msg_version, hdr->msg_sz); - if (WARN_ON((sz + ctx->authsize) > sizeof(msg->payload))) + if (WARN_ON((req->req_sz + ctx->authsize) > sizeof(msg->payload))) return -EBADMSG; memcpy(iv, &hdr->msg_seqno, min(sizeof(iv), sizeof(hdr->msg_seqno))); - aesgcm_encrypt(ctx, msg->payload, payload, sz, &hdr->algo, AAD_LEN, - iv, hdr->authtag); + aesgcm_encrypt(ctx, msg->payload, req->req_buf, req->req_sz, &hdr->algo, + AAD_LEN, iv, hdr->authtag); return 0; } -static int __handle_guest_request(struct snp_guest_dev *snp_dev, u64 exit_code, +static int __handle_guest_request(struct snp_guest_dev *snp_dev, struct snp_guest_req *req, struct snp_guest_request_ioctl *rio) { unsigned long req_start = jiffies; @@ -269,7 +268,7 @@ retry_request: * sequence number must be incremented or the VMPCK must be deleted to * prevent reuse of the IV. */ - rc = snp_issue_guest_request(exit_code, &snp_dev->input, rio); + rc = snp_issue_guest_request(req, &snp_dev->input, rio); switch (rc) { case -ENOSPC: /* @@ -280,7 +279,7 @@ retry_request: * IV reuse. */ override_npages = snp_dev->input.data_npages; - exit_code = SVM_VMGEXIT_GUEST_REQUEST; + req->exit_code = SVM_VMGEXIT_GUEST_REQUEST; /* * Override the error to inform callers the given extended @@ -340,10 +339,8 @@ retry_request: return rc; } -static int handle_guest_request(struct snp_guest_dev *snp_dev, u64 exit_code, - struct snp_guest_request_ioctl *rio, u8 type, - void *req_buf, size_t req_sz, void *resp_buf, - u32 resp_sz) +static int snp_send_guest_request(struct snp_guest_dev *snp_dev, struct snp_guest_req *req, + struct snp_guest_request_ioctl *rio) { u64 seqno; int rc; @@ -357,7 +354,7 @@ static int handle_guest_request(struct snp_guest_dev *snp_dev, u64 exit_code, memset(snp_dev->response, 0, sizeof(struct snp_guest_msg)); /* Encrypt the userspace provided payload in snp_dev->secret_request. */ - rc = enc_payload(snp_dev, seqno, rio->msg_version, type, req_buf, req_sz); + rc = enc_payload(snp_dev, seqno, req); if (rc) return rc; @@ -368,7 +365,7 @@ static int handle_guest_request(struct snp_guest_dev *snp_dev, u64 exit_code, memcpy(snp_dev->request, &snp_dev->secret_request, sizeof(snp_dev->secret_request)); - rc = __handle_guest_request(snp_dev, exit_code, rio); + rc = __handle_guest_request(snp_dev, req, rio); if (rc) { if (rc == -EIO && rio->exitinfo2 == SNP_GUEST_VMM_ERR(SNP_GUEST_VMM_ERR_INVALID_LEN)) @@ -382,7 +379,7 @@ static int handle_guest_request(struct snp_guest_dev *snp_dev, u64 exit_code, return rc; } - rc = verify_and_dec_payload(snp_dev, resp_buf, resp_sz); + rc = verify_and_dec_payload(snp_dev, req); if (rc) { dev_alert(snp_dev->dev, "Detected unexpected decode failure from ASP. rc: %d\n", rc); snp_disable_vmpck(snp_dev); @@ -401,6 +398,7 @@ static int get_report(struct snp_guest_dev *snp_dev, struct snp_guest_request_io { struct snp_report_req *report_req = &snp_dev->req.report; struct snp_report_resp *report_resp; + struct snp_guest_req req = {}; int rc, resp_len; lockdep_assert_held(&snp_cmd_mutex); @@ -421,8 +419,16 @@ static int get_report(struct snp_guest_dev *snp_dev, struct snp_guest_request_io if (!report_resp) return -ENOMEM; - rc = handle_guest_request(snp_dev, SVM_VMGEXIT_GUEST_REQUEST, arg, SNP_MSG_REPORT_REQ, - report_req, sizeof(*report_req), report_resp->data, resp_len); + req.msg_version = arg->msg_version; + req.msg_type = SNP_MSG_REPORT_REQ; + req.vmpck_id = vmpck_id; + req.req_buf = report_req; + req.req_sz = sizeof(*report_req); + req.resp_buf = report_resp->data; + req.resp_sz = resp_len; + req.exit_code = SVM_VMGEXIT_GUEST_REQUEST; + + rc = snp_send_guest_request(snp_dev, &req, arg); if (rc) goto e_free; @@ -438,6 +444,7 @@ static int get_derived_key(struct snp_guest_dev *snp_dev, struct snp_guest_reque { struct snp_derived_key_req *derived_key_req = &snp_dev->req.derived_key; struct snp_derived_key_resp derived_key_resp = {0}; + struct snp_guest_req req = {}; int rc, resp_len; /* Response data is 64 bytes and max authsize for GCM is 16 bytes. */ u8 buf[64 + 16]; @@ -460,8 +467,16 @@ static int get_derived_key(struct snp_guest_dev *snp_dev, struct snp_guest_reque sizeof(*derived_key_req))) return -EFAULT; - rc = handle_guest_request(snp_dev, SVM_VMGEXIT_GUEST_REQUEST, arg, SNP_MSG_KEY_REQ, - derived_key_req, sizeof(*derived_key_req), buf, resp_len); + req.msg_version = arg->msg_version; + req.msg_type = SNP_MSG_KEY_REQ; + req.vmpck_id = vmpck_id; + req.req_buf = derived_key_req; + req.req_sz = sizeof(*derived_key_req); + req.resp_buf = buf; + req.resp_sz = resp_len; + req.exit_code = SVM_VMGEXIT_GUEST_REQUEST; + + rc = snp_send_guest_request(snp_dev, &req, arg); if (rc) return rc; @@ -482,6 +497,7 @@ static int get_ext_report(struct snp_guest_dev *snp_dev, struct snp_guest_reques { struct snp_ext_report_req *report_req = &snp_dev->req.ext_report; struct snp_report_resp *report_resp; + struct snp_guest_req req = {}; int ret, npages = 0, resp_len; sockptr_t certs_address; @@ -529,9 +545,17 @@ cmd: return -ENOMEM; snp_dev->input.data_npages = npages; - ret = handle_guest_request(snp_dev, SVM_VMGEXIT_EXT_GUEST_REQUEST, arg, SNP_MSG_REPORT_REQ, - &report_req->data, sizeof(report_req->data), - report_resp->data, resp_len); + + req.msg_version = arg->msg_version; + req.msg_type = SNP_MSG_REPORT_REQ; + req.vmpck_id = vmpck_id; + req.req_buf = &report_req->data; + req.req_sz = sizeof(report_req->data); + req.resp_buf = report_resp->data; + req.resp_sz = resp_len; + req.exit_code = SVM_VMGEXIT_EXT_GUEST_REQUEST; + + ret = snp_send_guest_request(snp_dev, &req, arg); /* If certs length is invalid then copy the returned length */ if (arg->vmm_error == SNP_GUEST_VMM_ERR_INVALID_LEN) { @@ -1057,7 +1081,7 @@ static int __init sev_guest_probe(struct platform_device *pdev) misc->name = DEVICE_NAME; misc->fops = &snp_guest_fops; - /* initial the input address for guest request */ + /* Initialize the input addresses for guest request */ snp_dev->input.req_gpa = __pa(snp_dev->request); snp_dev->input.resp_gpa = __pa(snp_dev->response); snp_dev->input.data_gpa = __pa(snp_dev->certs_data); 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