s390/uv: Retrieve UV secrets support (7c9137af) · Commits · git / linux-net

arch/s390/include/asm/uv.h

+134 −2

Original line number	Diff line number	Diff line
		@@ -2,7 +2,7 @@
		/*
		* Ultravisor Interfaces
		*
		* Copyright IBM Corp. 2019, 2022
		* Copyright IBM Corp. 2019, 2024
		*
		* Author(s):
		* Vasily Gorbik <gor@linux.ibm.com>
		@@ -63,6 +63,7 @@
		#define UVC_CMD_ADD_SECRET 0x1031
		#define UVC_CMD_LIST_SECRETS 0x1033
		#define UVC_CMD_LOCK_SECRETS 0x1034
		#define UVC_CMD_RETR_SECRET 0x1035

		/* Bits in installed uv calls */
		enum uv_cmds_inst {
		@@ -96,6 +97,7 @@ enum uv_cmds_inst {
		BIT_UVC_CMD_ADD_SECRET = 29,
		BIT_UVC_CMD_LIST_SECRETS = 30,
		BIT_UVC_CMD_LOCK_SECRETS = 31,
		BIT_UVC_CMD_RETR_SECRET = 33,
		BIT_UVC_CMD_QUERY_KEYS = 34,
		};

		@@ -335,7 +337,6 @@ struct uv_cb_dump_complete {
		* A common UV call struct for pv guests that contains a single address
		* Examples:
		* Add Secret
		* List Secrets
		*/
		struct uv_cb_guest_addr {
		struct uv_cb_header header;
		@@ -344,6 +345,91 @@ struct uv_cb_guest_addr {
		u64 reserved28[4];
		} __packed __aligned(8);

		#define UVC_RC_RETR_SECR_BUF_SMALL 0x0109
		#define UVC_RC_RETR_SECR_STORE_EMPTY 0x010f
		#define UVC_RC_RETR_SECR_INV_IDX 0x0110
		#define UVC_RC_RETR_SECR_INV_SECRET 0x0111

		struct uv_cb_retr_secr {
		struct uv_cb_header header;
		u64 reserved08[2];
		u16 secret_idx;
		u16 reserved1a;
		u32 buf_size;
		u64 buf_addr;
		u64 reserved28[4];
		} __packed __aligned(8);

		struct uv_cb_list_secrets {
		struct uv_cb_header header;
		u64 reserved08[2];
		u8 reserved18[6];
		u16 start_idx;
		u64 list_addr;
		u64 reserved28[4];
		} __packed __aligned(8);

		enum uv_secret_types {
		UV_SECRET_INVAL = 0x0,
		UV_SECRET_NULL = 0x1,
		UV_SECRET_ASSOCIATION = 0x2,
		UV_SECRET_PLAIN = 0x3,
		UV_SECRET_AES_128 = 0x4,
		UV_SECRET_AES_192 = 0x5,
		UV_SECRET_AES_256 = 0x6,
		UV_SECRET_AES_XTS_128 = 0x7,
		UV_SECRET_AES_XTS_256 = 0x8,
		UV_SECRET_HMAC_SHA_256 = 0x9,
		UV_SECRET_HMAC_SHA_512 = 0xa,
		/* 0x0b - 0x10 reserved */
		UV_SECRET_ECDSA_P256 = 0x11,
		UV_SECRET_ECDSA_P384 = 0x12,
		UV_SECRET_ECDSA_P521 = 0x13,
		UV_SECRET_ECDSA_ED25519 = 0x14,
		UV_SECRET_ECDSA_ED448 = 0x15,
		};

		/**
		* uv_secret_list_item_hdr - UV secret metadata.
		* @index: Index of the secret in the secret list.
		* @type: Type of the secret. See `enum uv_secret_types`.
		* @length: Length of the stored secret.
		*/
		struct uv_secret_list_item_hdr {
		u16 index;
		u16 type;
		u32 length;
		} __packed __aligned(8);

		#define UV_SECRET_ID_LEN 32
		/**
		* uv_secret_list_item - UV secret entry.
		* @hdr: The metadata of this secret.
		* @id: The ID of this secret, not the secret itself.
		*/
		struct uv_secret_list_item {
		struct uv_secret_list_item_hdr hdr;
		u64 reserverd08;
		u8 id[UV_SECRET_ID_LEN];
		} __packed __aligned(8);

		/**
		* uv_secret_list - UV secret-metadata list.
		* @num_secr_stored: Number of secrets stored in this list.
		* @total_num_secrets: Number of secrets stored in the UV for this guest.
		* @next_secret_idx: positive number if there are more secrets available or zero.
		* @secrets: Up to 85 UV-secret metadata entries.
		*/
		struct uv_secret_list {
		u16 num_secr_stored;
		u16 total_num_secrets;
		u16 next_secret_idx;
		u16 reserved_06;
		u64 reserved_08;
		struct uv_secret_list_item secrets[85];
		} __packed __aligned(8);
		static_assert(sizeof(struct uv_secret_list) == PAGE_SIZE);

		static inline int __uv_call(unsigned long r1, unsigned long r2)
		{
		int cc;
		@@ -400,6 +486,48 @@ static inline int uv_cmd_nodata(u64 handle, u16 cmd, u16 rc, u16 rrc)
		return cc ? -EINVAL : 0;
		}

		/**
		* uv_list_secrets() - Do a List Secrets UVC.
		*
		* @buf: Buffer to write list into; size of one page.
		* @start_idx: The smallest index that should be included in the list.
		* For the fist invocation use 0.
		* @rc: Pointer to store the return code or NULL.
		* @rrc: Pointer to store the return reason code or NULL.
		*
		* This function calls the List Secrets UVC. The result is written into `buf`,
		* that needs to be at least one page of writable memory.
		* `buf` consists of:
		* * %struct uv_secret_list_hdr
		* * %struct uv_secret_list_item (multiple)
		*
		* For `start_idx` use _0_ for the first call. If there are more secrets available
		* but could not fit into the page then `rc` is `UVC_RC_MORE_DATA`.
		* In this case use `uv_secret_list_hdr.next_secret_idx` for `start_idx`.
		*
		* Context: might sleep.
		*
		* Return: The UVC condition code.
		*/
		static inline int uv_list_secrets(struct uv_secret_list *buf, u16 start_idx,
		u16 rc, u16 rrc)
		{
		struct uv_cb_list_secrets uvcb = {
		.header.len = sizeof(uvcb),
		.header.cmd = UVC_CMD_LIST_SECRETS,
		.start_idx = start_idx,
		.list_addr = (u64)buf,
		};
		int cc = uv_call_sched(0, (u64)&uvcb);

		if (rc)
		*rc = uvcb.header.rc;
		if (rrc)
		*rrc = uvcb.header.rrc;

		return cc;
		}

		struct uv_info {
		unsigned long inst_calls_list[4];
		unsigned long uv_base_stor_len;
		@@ -486,6 +614,10 @@ static inline int uv_remove_shared(unsigned long addr)
		return share(addr, UVC_CMD_REMOVE_SHARED_ACCESS);
		}

		int uv_get_secret_metadata(const u8 secret_id[UV_SECRET_ID_LEN],
		struct uv_secret_list_item_hdr *secret);
		int uv_retrieve_secret(u16 secret_idx, u8 *buf, size_t buf_size);

		extern int prot_virt_host;

		static inline int is_prot_virt_host(void)

arch/s390/kernel/uv.c

+128 −1

Original line number	Diff line number	Diff line
		@@ -2,7 +2,7 @@
		/*
		* Common Ultravisor functions and initialization
		*
		* Copyright IBM Corp. 2019, 2020
		* Copyright IBM Corp. 2019, 2024
		*/
		#define KMSG_COMPONENT "prot_virt"
		#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
		@@ -870,3 +870,130 @@ static int __init uv_sysfs_init(void)
		return rc;
		}
		device_initcall(uv_sysfs_init);

		/*
		* Find the secret with the secret_id in the provided list.
		*
		* Context: might sleep.
		*/
		static int find_secret_in_page(const u8 secret_id[UV_SECRET_ID_LEN],
		const struct uv_secret_list *list,
		struct uv_secret_list_item_hdr *secret)
		{
		u16 i;

		for (i = 0; i < list->total_num_secrets; i++) {
		if (memcmp(secret_id, list->secrets[i].id, UV_SECRET_ID_LEN) == 0) {
		*secret = list->secrets[i].hdr;
		return 0;
		}
		}
		return -ENOENT;
		}

		/*
		* Do the actual search for `uv_get_secret_metadata`.
		*
		* Context: might sleep.
		*/
		static int find_secret(const u8 secret_id[UV_SECRET_ID_LEN],
		struct uv_secret_list *list,
		struct uv_secret_list_item_hdr *secret)
		{
		u16 start_idx = 0;
		u16 list_rc;
		int ret;

		do {
		uv_list_secrets(list, start_idx, &list_rc, NULL);
		if (list_rc != UVC_RC_EXECUTED && list_rc != UVC_RC_MORE_DATA) {
		if (list_rc == UVC_RC_INV_CMD)
		return -ENODEV;
		else
		return -EIO;
		}
		ret = find_secret_in_page(secret_id, list, secret);
		if (ret == 0)
		return ret;
		start_idx = list->next_secret_idx;
		} while (list_rc == UVC_RC_MORE_DATA && start_idx < list->next_secret_idx);

		return -ENOENT;
		}

		/**
		* uv_get_secret_metadata() - get secret metadata for a given secret id.
		* @secret_id: search pattern.
		* @secret: output data, containing the secret's metadata.
		*
		* Search for a secret with the given secret_id in the Ultravisor secret store.
		*
		* Context: might sleep.
		*
		* Return:
		* * %0: - Found entry; secret->idx and secret->type are valid.
		* * %ENOENT - No entry found.
		* * %ENODEV: - Not supported: UV not available or command not available.
		* * %EIO: - Other unexpected UV error.
		*/
		int uv_get_secret_metadata(const u8 secret_id[UV_SECRET_ID_LEN],
		struct uv_secret_list_item_hdr *secret)
		{
		struct uv_secret_list *buf;
		int rc;

		buf = kzalloc(sizeof(*buf), GFP_KERNEL);
		if (!buf)
		return -ENOMEM;
		rc = find_secret(secret_id, buf, secret);
		kfree(buf);
		return rc;
		}
		EXPORT_SYMBOL_GPL(uv_get_secret_metadata);

		/**
		* uv_retrieve_secret() - get the secret value for the secret index.
		* @secret_idx: Secret index for which the secret should be retrieved.
		* @buf: Buffer to store retrieved secret.
		* @buf_size: Size of the buffer. The correct buffer size is reported as part of
		* the result from `uv_get_secret_metadata`.
		*
		* Calls the Retrieve Secret UVC and translates the UV return code into an errno.
		*
		* Context: might sleep.
		*
		* Return:
		* * %0 - Entry found; buffer contains a valid secret.
		* * %ENOENT: - No entry found or secret at the index is non-retrievable.
		* * %ENODEV: - Not supported: UV not available or command not available.
		* * %EINVAL: - Buffer too small for content.
		* * %EIO: - Other unexpected UV error.
		*/
		int uv_retrieve_secret(u16 secret_idx, u8 *buf, size_t buf_size)
		{
		struct uv_cb_retr_secr uvcb = {
		.header.len = sizeof(uvcb),
		.header.cmd = UVC_CMD_RETR_SECRET,
		.secret_idx = secret_idx,
		.buf_addr = (u64)buf,
		.buf_size = buf_size,
		};

		uv_call_sched(0, (u64)&uvcb);

		switch (uvcb.header.rc) {
		case UVC_RC_EXECUTED:
		return 0;
		case UVC_RC_INV_CMD:
		return -ENODEV;
		case UVC_RC_RETR_SECR_STORE_EMPTY:
		case UVC_RC_RETR_SECR_INV_SECRET:
		case UVC_RC_RETR_SECR_INV_IDX:
		return -ENOENT;
		case UVC_RC_RETR_SECR_BUF_SMALL:
		return -EINVAL;
		default:
		return -EIO;
		}
		}
		EXPORT_SYMBOL_GPL(uv_retrieve_secret);