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Re: [Qemu-devel] [PATCH v14 1/2] virtio-crypto: Add virtio crypto device
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From: |
Halil Pasic |
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Subject: |
Re: [Qemu-devel] [PATCH v14 1/2] virtio-crypto: Add virtio crypto device specification |
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Date: |
Wed, 16 Nov 2016 19:11:25 +0100 |
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User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 |
On 11/11/2016 10:23 AM, Gonglei wrote:
> The virtio crypto device is a virtual crypto device (ie. hardware
> crypto accelerator card). Currently, the virtio crypto device provides
> the following crypto services: CIPHER, MAC, HASH, and AEAD.
>
> In this patch, CIPHER, MAC, HASH, AEAD services are introduced.
>
> VIRTIO-153
>
> Signed-off-by: Gonglei <address@hidden>
> CC: Michael S. Tsirkin <address@hidden>
> CC: Cornelia Huck <address@hidden>
> CC: Stefan Hajnoczi <address@hidden>
> CC: Lingli Deng <address@hidden>
> CC: Jani Kokkonen <address@hidden>
> CC: Ola Liljedahl <address@hidden>
> CC: Varun Sethi <address@hidden>
> CC: Zeng Xin <address@hidden>
> CC: Keating Brian <address@hidden>
> CC: Ma Liang J <address@hidden>
> CC: Griffin John <address@hidden>
> CC: Hanweidong <address@hidden>
> CC: Mihai Claudiu Caraman <address@hidden>
> ---
> content.tex | 2 +
> virtio-crypto.tex | 945
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++
> 2 files changed, 947 insertions(+)
> create mode 100644 virtio-crypto.tex
>
> diff --git a/content.tex b/content.tex
> index 4b45678..ab75f78 100644
> --- a/content.tex
> +++ b/content.tex
> @@ -5750,6 +5750,8 @@ descriptor for the \field{sense_len}, \field{residual},
> \field{status_qualifier}, \field{status}, \field{response} and
> \field{sense} fields.
>
> +\input{virtio-crypto.tex}
> +
> \chapter{Reserved Feature Bits}\label{sec:Reserved Feature Bits}
>
> Currently there are three device-independent feature bits defined:
> diff --git a/virtio-crypto.tex b/virtio-crypto.tex
> new file mode 100644
> index 0000000..9f7faf0
> --- /dev/null
> +++ b/virtio-crypto.tex
> @@ -0,0 +1,945 @@
> +\section{Crypto Device}\label{sec:Device Types / Crypto Device}
> +
> +The virtio crypto device is a virtual cryptography device as well as a kind
> of
> +virtual hardware accelerator for virtual machines. The encryption and
> +decryption requests are placed in the data queue and are ultimately handled
> by the
~~~~~~~~~~~~~~
The data queue can be misleading since its rather any of the data active
queues.
> +backend crypto accelerators. The second queue is the control queue used to
> create
~~~~~~~~~~~~
This could be confusing since it is a second type or kind of queue but
not necessarily the queue with index 1.
> +or destroy sessions for symmetric algorithms and will control some advanced
> +features in the future. The virtio crypto device provides the following
> crypto
Promising future advanced features seems to be out of scope for this
specification.
> +services: CIPHER, MAC, HASH, and AEAD.
> +
> +
> +\subsection{Device ID}\label{sec:Device Types / Crypto Device / Device ID}
> +
> +20
> +
> +\subsection{Virtqueues}\label{sec:Device Types / Crypto Device / Virtqueues}
> +
> +\begin{description}
> +\item[0] dataq1
> +\item[\ldots]
> +\item[N-1] dataqN
> +\item[N] controlq
> +\end{description}
> +
> +N is set by \field{max_dataqueues}.
> +
> +\subsection{Feature bits}\label{sec:Device Types / Crypto Device / Feature
> bits}
> +
> +Undefined currently.
Could use "None currently defined." like entropy device.
> +
> +\subsection{Device configuration layout}\label{sec:Device Types / Crypto
> Device / Device configuration layout}
> +
> +The following driver-read-only configuration fields are defined:
> +
> +\begin{lstlisting}
> +struct virtio_crypto_config {
> + le32 status;
> + le32 max_dataqueues;
> + le32 crypto_services;
> + /* Detailed algorithms mask */
> + le32 cipher_algo_l;
> + le32 cipher_algo_h;
> + le32 hash_algo;
> + le32 mac_algo_l;
> + le32 mac_algo_h;
> + le32 aead_algo;
> + /* Maximum length of cipher key */
> + le32 max_cipher_key_len;
> + /* Maximum length of authenticated key */
> + le32 max_auth_key_len;
> + le32 reserve;
> + /* Maximum size of each crypto request's content */
> + le64 max_size;
> +};
> +\end{lstlisting}
> +
> +The value of the \field{status} field is VIRTIO_CRYPTO_S_HW_READY or
> VIRTIO_CRYPTO_S_STARTED.
> +
> +\begin{lstlisting}
> +#define VIRTIO_CRYPTO_S_HW_READY (1 << 0)
> +#define VIRTIO_CRYPTO_S_STARTED (1 << 1)
> +\end{lstlisting}
> +
Could not really figure out what this status actually does and how does
it relate to the device status field if at all.
Furthermore I see no mention of VIRTIO_CRYPTO_S_STARTED except for this
one, so the only thing I can think of is that it's the initial value and
means hardware not ready (you state these are the only two values).
This however does not seem consistent with what your QEMU reference
implementation does. Another thing is your implementations seem to
use VIRTIO_CRYPTO_S_HW_READY as flag but your specification would
(prohibit combining flags because you get another value).
There are more comments on this topic below.
> +The following driver-read-only fields include \field{max_dataqueues}, which
> specifies the
> +maximum number of data virtqueues (dataq1\ldots dataqN), and
> \field{crypto_services},
> +which indicates the crypto services the virtio crypto supports.
> +
> +The following services are defined:
> +
> +\begin{lstlisting}
> +/* CIPHER service */
> +#define VIRTIO_CRYPTO_SERVICE_CIPHER 0
> +/* HASH service */
> +#define VIRTIO_CRYPTO_SERVICE_HASH 1
> +/* MAC (Message Authentication Codes) service */
> +#define VIRTIO_CRYPTO_SERVICE_MAC 2
> +/* AEAD (Authenticated Encryption with Associated Data) service */
> +#define VIRTIO_CRYPTO_SERVICE_AEAD 3
> +\end{lstlisting}
> +
> +The last driver-read-only fields specify detailed algorithms masks
> +the device offers for corresponding services. The following CIPHER algorithms
> +are defined:
> +
> +\begin{lstlisting}
> +#define VIRTIO_CRYPTO_NO_CIPHER 0
> +#define VIRTIO_CRYPTO_CIPHER_ARC4 1
> +#define VIRTIO_CRYPTO_CIPHER_AES_ECB 2
> +#define VIRTIO_CRYPTO_CIPHER_AES_CBC 3
> +#define VIRTIO_CRYPTO_CIPHER_AES_CTR 4
> +#define VIRTIO_CRYPTO_CIPHER_DES_ECB 5
> +#define VIRTIO_CRYPTO_CIPHER_DES_CBC 6
> +#define VIRTIO_CRYPTO_CIPHER_3DES_ECB 7
> +#define VIRTIO_CRYPTO_CIPHER_3DES_CBC 8
> +#define VIRTIO_CRYPTO_CIPHER_3DES_CTR 9
> +#define VIRTIO_CRYPTO_CIPHER_KASUMI_F8 10
> +#define VIRTIO_CRYPTO_CIPHER_SNOW3G_UEA2 11
> +#define VIRTIO_CRYPTO_CIPHER_AES_F8 12
> +#define VIRTIO_CRYPTO_CIPHER_AES_XTS 13
> +#define VIRTIO_CRYPTO_CIPHER_ZUC_EEA3 14
> +\end{lstlisting}
> +
You could clarify that these values have double meaning. Each value
uniquely identifies an cipher algorithm and a bit in a 'algorithm mask'
bitmap represented as le32 cipher_algo_l and le32 cipher_algo_h so that
availability could be checked like this:
bool is_avail(uint16_t flag)
{
return flag < 32 ? (le32_to_cpu(config.chiper_algo_l) & (1UL << flag)) :
(flag < 64 ? (le32_to_cpu(config.chiper_algo_h) & (1UL << (flag -
32))): false);
}
I'm curious what is the purpose of VIRTIO_CRYPTO_NO_CIPHER?
> +The following HASH algorithms are defined:
> +
> +\begin{lstlisting}
> +#define VIRTIO_CRYPTO_NO_HASH 0
> +#define VIRTIO_CRYPTO_HASH_MD5 1
> +#define VIRTIO_CRYPTO_HASH_SHA1 2
> +#define VIRTIO_CRYPTO_HASH_SHA_224 3
> +#define VIRTIO_CRYPTO_HASH_SHA_256 4
> +#define VIRTIO_CRYPTO_HASH_SHA_384 5
> +#define VIRTIO_CRYPTO_HASH_SHA_512 6
> +#define VIRTIO_CRYPTO_HASH_SHA3_224 7
> +#define VIRTIO_CRYPTO_HASH_SHA3_256 8
> +#define VIRTIO_CRYPTO_HASH_SHA3_384 9
> +#define VIRTIO_CRYPTO_HASH_SHA3_512 10
> +#define VIRTIO_CRYPTO_HASH_SHA3_SHAKE128 11
> +#define VIRTIO_CRYPTO_HASH_SHA3_SHAKE256 12
> +\end{lstlisting}
> +
> +The following MAC algorithms are defined:
> +
> +\begin{lstlisting}
> +#define VIRTIO_CRYPTO_NO_MAC 0
> +#define VIRTIO_CRYPTO_MAC_HMAC_MD5 1
> +#define VIRTIO_CRYPTO_MAC_HMAC_SHA1 2
> +#define VIRTIO_CRYPTO_MAC_HMAC_SHA_224 3
> +#define VIRTIO_CRYPTO_MAC_HMAC_SHA_256 4
> +#define VIRTIO_CRYPTO_MAC_HMAC_SHA_384 5
> +#define VIRTIO_CRYPTO_MAC_HMAC_SHA_512 6
> +#define VIRTIO_CRYPTO_MAC_CMAC_3DES 25
> +#define VIRTIO_CRYPTO_MAC_CMAC_AES 26
> +#define VIRTIO_CRYPTO_MAC_KASUMI_F9 27
> +#define VIRTIO_CRYPTO_MAC_SNOW3G_UIA2 28
> +#define VIRTIO_CRYPTO_MAC_GMAC_AES 41
> +#define VIRTIO_CRYPTO_MAC_GMAC_TWOFISH 42
> +#define VIRTIO_CRYPTO_MAC_CBCMAC_AES 49
> +#define VIRTIO_CRYPTO_MAC_CBCMAC_KASUMI_F9 50
> +#define VIRTIO_CRYPTO_MAC_XCBC_AES 53
> +#define VIRTIO_CRYPTO_MAC_ZUC_EIA3 54
> +\end{lstlisting}
> +
> +The following AEAD algorithms are defined:
> +
> +\begin{lstlisting}
> +#define VIRTIO_CRYPTO_NO_AEAD 0
> +#define VIRTIO_CRYPTO_AEAD_GCM 1
> +#define VIRTIO_CRYPTO_AEAD_CCM 2
> +#define VIRTIO_CRYPTO_AEAD_CHACHA20_POLY1305 3
> +\end{lstlisting}
> +
> +\begin{note}
> +Any other value is reserved for future use.
> +\end{note}
> +
> +\devicenormative{\subsubsection}{Device configuration layout}{Device Types /
> Crypto Device / Device configuration layout}
> +
> +\begin{itemize*}
> +\item The device MUST set \field{max_dataqueues} to between 1 and 65535
> inclusive.
> +\item The device MUST set \field{status} based on the status of the
> hardware-backed implementation.
> +\item The device MUST accept and handle requests after \field{status} is set
> to VIRTIO_CRYPTO_S_HW_READY.
Not sure this is a configuration layout requirement.
> +\item The device MUST set \field{crypto_services} based on the crypto
> services the device offers.
> +\item The device MUST set detailed algorithms masks based on the
> \field{crypto_services} field.
> +\item The device MUST set \field{max_size} to show the maximum size of
> crypto request the device supports.
> +\item The device MUST set \field{max_cipher_key_len} to show the maximum
> length of cipher key if the device supports CIPHER service.
> +\item The device MUST set \field{max_auth_key_len} to show the maximum
> length of authenticated key if the device supports MAC service.
> +\end{itemize*}
> +
> +\drivernormative{\subsubsection}{Device configuration layout}{Device Types /
> Crypto Device / Device configuration layout}
> +
> +\begin{itemize*}
> +\item The driver MUST read the ready \field{status} from the bottom bit of
> status to check whether the hardware-backed
> + implementation is ready or not, and the driver MUST reread it after
> the device reset.
> +\item The driver MUST NOT transmit any packets to the device if the ready
> \field{status} is not set.
Not sure this is a configuration layout requirement (read: I think it is
not). I would also rather opt for SHOULD NOT if the think is that this
can change on the fly (it might be difficult to say when is the ready
set and when not: e.g. the driver changes to not ready and the interrupt
for the configuration change is in flight). Well as I said I need some
clarification regarding this whole status thing.
An other thing you probably should consider: when you establish a
contract between the driver and the device and state a requirement
regarding one party X I think it is always a good idea to think about
what is the other party Y supposed to do if X violates the contract (of
course doing noting about it can be an alternative but the the question
of the associated risk becomes even more prominent.)
> +\item The driver MAY read \field{max_dataqueues} field to discover the
> number of data queues the device supports.
Ain't this MAY contradictory with "The driver MUST identify and initialize
the control virtqueue"? If that is a MUST, MUST is implied here too, or?
> +\item The driver MUST read \field{crypto_services} field to discover which
> services the device is able to offer.
> +\item The driver MUST read the detailed algorithms fields based on
> \field{crypto_services} field.
> +\item The driver SHOULD read \field{max_size} to discover the maximum size
> of crypto request the device supports.
> +\item The driver SHOULD read \field{max_cipher_key_len} to discover the
> maximum length of cipher key the device supports.
> +\item The driver SHOULD read \field{max_auth_key_len} to discover the
> maximum length of authenticated key the device supports.
> +\end{itemize*}
> +
Stopped reviewing here.
> +\subsection{Device Initialization}\label{sec:Device Types / Crypto Device /
> Device Initialization}
> +
> +\drivernormative{\subsubsection}{Device Initialization}{Device Types /
> Crypto Device / Device Initialization}
> +
> +\begin{itemize*}
> +\item The driver MUST identify and initialize the control virtqueue.
> +\item The driver MUST read the supported crypto services from bits of
> \field{crypto_services}.
> +\item The driver MUST read the supported algorithms based on
> \field{crypto_services} field.
> +\end{itemize*}
> +
> +\devicenormative{\subsubsection}{Device Initialization}{Device Types /
> Crypto Device / Device Initialization}
> +
> +\begin{itemize*}
> +\item The device MUST be configured with at least one accelerator which
> executes backend crypto operations.
> +\item The device MUST write the \field{crypto_services} field based on the
> capacities of the backend accelerator.
> +\end{itemize*}
> +
> +\subsection{Device Operation}\label{sec:Device Types / Crypto Device /
> Device Operation}
> +
> +Packets can be transmitted by placing them in both the controlq and dataq.
> +Packets consist of a general header and a service-specific request.
> +Where 'general header' is for all crypto requests, and 'service specific
> requests'
> +are composed of operation parameter + output data + input data in general.
> +Operation parameters are algorithm-specific parameters, output data is the
> +data that should be utilized in operations, and input data is equal to
> +"operation result + result data".
> +
> +\begin{note}
> +The basic unit of all data length the byte.
> +\end{note}
> +
> +The general header for controlq is as follows:
> +
> +\begin{lstlisting}
> +#define VIRTIO_CRYPTO_OPCODE(service, op) (((service) << 8) | (op))
> +
> +struct virtio_crypto_ctrl_header {
> +#define VIRTIO_CRYPTO_CIPHER_CREATE_SESSION \
> + VIRTIO_CRYPTO_OPCODE(VIRTIO_CRYPTO_SERVICE_CIPHER, 0x02)
> +#define VIRTIO_CRYPTO_CIPHER_DESTROY_SESSION \
> + VIRTIO_CRYPTO_OPCODE(VIRTIO_CRYPTO_SERVICE_CIPHER, 0x03)
> +#define VIRTIO_CRYPTO_HASH_CREATE_SESSION \
> + VIRTIO_CRYPTO_OPCODE(VIRTIO_CRYPTO_SERVICE_HASH, 0x02)
> +#define VIRTIO_CRYPTO_HASH_DESTROY_SESSION \
> + VIRTIO_CRYPTO_OPCODE(VIRTIO_CRYPTO_SERVICE_HASH, 0x03)
> +#define VIRTIO_CRYPTO_MAC_CREATE_SESSION \
> + VIRTIO_CRYPTO_OPCODE(VIRTIO_CRYPTO_SERVICE_MAC, 0x02)
> +#define VIRTIO_CRYPTO_MAC_DESTROY_SESSION \
> + VIRTIO_CRYPTO_OPCODE(VIRTIO_CRYPTO_SERVICE_MAC, 0x03)
> +#define VIRTIO_CRYPTO_AEAD_CREATE_SESSION \
> + VIRTIO_CRYPTO_OPCODE(VIRTIO_CRYPTO_SERVICE_AEAD, 0x02)
> +#define VIRTIO_CRYPTO_AEAD_DESTROY_SESSION \
> + VIRTIO_CRYPTO_OPCODE(VIRTIO_CRYPTO_SERVICE_AEAD, 0x03)
> + le32 opcode;
> + le32 algo;
> + le32 flag;
> + /* data virtqueue id */
> + le32 queue_id;
> +};
> +\end{lstlisting}
> +
> +The general header of dataq:
> +
> +\begin{lstlisting}
> +struct virtio_crypto_op_header {
> +#define VIRTIO_CRYPTO_CIPHER_ENCRYPT \
> + VIRTIO_CRYPTO_OPCODE(VIRTIO_CRYPTO_SERVICE_CIPHER, 0x00)
> +#define VIRTIO_CRYPTO_CIPHER_DECRYPT \
> + VIRTIO_CRYPTO_OPCODE(VIRTIO_CRYPTO_SERVICE_CIPHER, 0x01)
> +#define VIRTIO_CRYPTO_HASH \
> + VIRTIO_CRYPTO_OPCODE(VIRTIO_CRYPTO_SERVICE_HASH, 0x00)
> +#define VIRTIO_CRYPTO_MAC \
> + VIRTIO_CRYPTO_OPCODE(VIRTIO_CRYPTO_SERVICE_MAC, 0x00)
> +#define VIRTIO_CRYPTO_AEAD_ENCRYPT \
> + VIRTIO_CRYPTO_OPCODE(VIRTIO_CRYPTO_SERVICE_AEAD, 0x00)
> +#define VIRTIO_CRYPTO_AEAD_DECRYPT \
> + VIRTIO_CRYPTO_OPCODE(VIRTIO_CRYPTO_SERVICE_AEAD, 0x01)
> + le32 opcode;
> + /* algo should be service-specific algorithms */
> + le32 algo;
> + /* session_id should be service-specific algorithms */
> + le64 session_id;
> + /* control flag to control the request */
> + le32 flag;
> + le32 padding;
> +};
> +\end{lstlisting}
> +
> +The device can set the operation status as follows: VIRTIO_CRYPTO_OK:
> success;
> +VIRTIO_CRYPTO_ERR: failure or device error; VIRTIO_CRYPTO_NOTSUPP: not
> supported;
> +VIRTIO_CRYPTO_INVSESS: invalid session ID when executing crypto operations.
> +
> +\begin{lstlisting}
> +enum VIRITO_CRYPTO_STATUS {
> + VIRTIO_CRYPTO_OK = 0,
> + VIRTIO_CRYPTO_ERR = 1,
> + VIRTIO_CRYPTO_BADMSG = 2,
> + VIRTIO_CRYPTO_NOTSUPP = 3,
> + VIRTIO_CRYPTO_INVSESS = 4,
> + VIRTIO_CRYPTO_MAX
> +};
> +\end{lstlisting}
> +
> +\subsubsection{Control Virtqueue}\label{sec:Device Types / Crypto Device /
> Device Operation / Control Virtqueue}
> +
> +The driver uses the control virtqueue to send control commands to the
> +device which handles the non-data plane operations, such as session
> +operations (See \ref{sec:Device Types / Crypto Device / Device Operation /
> Control Virtqueue / Session operation}).
> +
> +The packet of controlq:
> +
> +\begin{lstlisting}
> +struct virtio_crypto_op_ctrl_req {
> + struct virtio_crypto_ctrl_header header;
> +
> + union {
> + struct virtio_crypto_sym_create_session_req sym_create_session;
> + struct virtio_crypto_hash_create_session_req hash_create_session;
> + struct virtio_crypto_mac_create_session_req mac_create_session;
> + struct virtio_crypto_aead_create_session_req aead_create_session;
> + struct virtio_crypto_destroy_session_req destroy_session;
> + } u;
> +};
> +\end{lstlisting}
> +
> +The header is the general header, and the union is of the algorithm-specific
> type,
> +which is set by the driver. All the properties in the union are shown as
> follows.
> +
> +\paragraph{Session operation}\label{sec:Device Types / Crypto Device /
> Device Operation / Control Virtqueue / Session operation}
> +
> +The symmetric algorithms involve the concept of sessions. A session is a
> +handle which describes the cryptographic parameters to be applied to
> +a number of buffers. The data within a session handle includes the following:
> +
> +\begin{enumerate}
> +\item The operation (CIPHER, HASH/MAC or both, and if both, the order in
> + which the algorithms should be applied).
> +\item The CIPHER set data, including the CIPHER algorithm and mode,
> + the key and its length, and the direction (encryption or decryption).
> +\item The HASH/MAC set data, including the HASH algorithm or MAC algorithm,
> + and hash result length (to allow for truncation).
> +\begin{itemize*}
> +\item Authenticated mode can refer to MAC, which requires that the key and
> + its length are also specified.
> +\item For nested mode, the inner and outer prefix data and length are
> specified,
> + as well as the outer HASH algorithm.
> +\end{itemize*}
> +\end{enumerate}
> +
> +The following structure stores the result of session creation set by the
> device:
> +
> +\begin{lstlisting}
> +struct virtio_crypto_session_input {
> + /* Device-writable part */
> + le64 session_id;
> + le32 status;
> + le32 padding;
> +};
> +\end{lstlisting}
> +
> +A request to destroy a session includes the following information:
> +
> +\begin{lstlisting}
> +struct virtio_crypto_destroy_session_req {
> + /* Device-readable part */
> + le64 session_id;
> + /* Device-writable part */
> + le32 status;
> + le32 padding;
> +};
> +\end{lstlisting}
> +
> +\subparagraph{Session operation: HASH session}\label{sec:Device Types /
> Crypto Device / Device
> +Operation / Control Virtqueue / Session operation / Session operation: HASH
> session}
> +
> +The packet of HASH session is as follows:
> +
> +\begin{lstlisting}
> +struct virtio_crypto_hash_session_para {
> + /* See VIRTIO_CRYPTO_HASH_* above */
> + le32 algo;
> + /* hash result length */
> + le32 hash_result_len;
> +};
> +struct virtio_crypto_hash_create_session_req {
> + /* Device-readable part */
> + struct virtio_crypto_hash_session_para para;
> + /* Device-writable part */
> + struct virtio_crypto_session_input input;
> +};
> +\end{lstlisting}
> +
> +\subparagraph{Session operation: MAC session}\label{sec:Device Types /
> Crypto Device / Device
> +Operation / Control Virtqueue / Session operation / Session operation: MAC
> session}
> +
> +The packet of MAC session is as follows:
> +
> +\begin{lstlisting}
> +struct virtio_crypto_mac_session_para {
> + /* See VIRTIO_CRYPTO_MAC_* above */
> + le32 algo;
> + /* hash result length */
> + le32 hash_result_len;
> + /* length of authenticated key */
> + le32 auth_key_len;
> + le32 padding;
> +};
> +
> +struct virtio_crypto_mac_create_session_req {
> + /* Device-readable part */
> + struct virtio_crypto_mac_session_para para;
> + /* The authenticated key */
> + u8 auth_key[auth_key_len];
> +
> + /* Device-writable part */
> + struct virtio_crypto_session_input input;
> +};
> +\end{lstlisting}
> +
> +\subparagraph{Session operation: Symmetric algorithms
> session}\label{sec:Device Types / Crypto Device / Device
> +Operation / Control Virtqueue / Session operation / Session operation:
> Symmetric algorithms session}
> +
> +The request of symmetric session includes two parts, CIPHER algorithms and
> chain
> +algorithms (chaining CIPHER and HASH/MAC). The packet for CIPHER session is
> as follows:
> +
> +\begin{lstlisting}
> +struct virtio_crypto_cipher_session_para {
> + /* See VIRTIO_CRYPTO_CIPHER* above */
> + le32 algo;
> + /* length of key */
> + le32 keylen;
> +#define VIRTIO_CRYPTO_OP_ENCRYPT 1
> +#define VIRTIO_CRYPTO_OP_DECRYPT 2
> + /* encryption or decryption */
> + le32 op;
> + le32 padding;
> +};
> +
> +struct virtio_crypto_cipher_session_req {
> + /* Device-readable part */
> + struct virtio_crypto_cipher_session_para para;
> + /* The cipher key */
> + u8 cipher_key[keylen];
> +
> + /* Device-writable part */
> + struct virtio_crypto_session_input input;
> +};
> +\end{lstlisting}
> +
> +The packet for algorithm chaining is as follows:
> +
> +\begin{lstlisting}
> +struct virtio_crypto_alg_chain_session_para {
> +#define VIRTIO_CRYPTO_SYM_ALG_CHAIN_ORDER_HASH_THEN_CIPHER 1
> +#define VIRTIO_CRYPTO_SYM_ALG_CHAIN_ORDER_CIPHER_THEN_HASH 2
> + le32 alg_chain_order;
> +/* Plain hash */
> +#define VIRTIO_CRYPTO_SYM_HASH_MODE_PLAIN 1
> +/* Authenticated hash (mac) */
> +#define VIRTIO_CRYPTO_SYM_HASH_MODE_AUTH 2
> +/* Nested hash */
> +#define VIRTIO_CRYPTO_SYM_HASH_MODE_NESTED 3
> + le32 hash_mode;
> + struct virtio_crypto_cipher_session_para cipher_param;
> + union {
> + struct virtio_crypto_hash_session_para hash_param;
> + struct virtio_crypto_mac_session_para mac_param;
> + } u;
> + /* length of the additional authenticated data (AAD) in bytes */
> + le32 aad_len;
> + le32 padding;
> +};
> +
> +struct virtio_crypto_alg_chain_session_req {
> + /* Device-readable part */
> + struct virtio_crypto_alg_chain_session_para para;
> + /* The cipher key */
> + u8 cipher_key[keylen];
> + /* The authenticated key */
> + u8 auth_key[auth_key_len];
> +
> + /* Device-writable part */
> + struct virtio_crypto_session_input input;
> +};
> +\end{lstlisting}
> +
> +The packet for symmetric algorithm is as follows:
> +
> +\begin{lstlisting}
> +struct virtio_crypto_sym_create_session_req {
> + union {
> + struct virtio_crypto_cipher_session_req cipher;
> + struct virtio_crypto_alg_chain_session_req chain;
> + } u;
> +
> + /* Device-readable part */
> +
> +/* No operation */
> +#define VIRTIO_CRYPTO_SYM_OP_NONE 0
> +/* Cipher only operation on the data */
> +#define VIRTIO_CRYPTO_SYM_OP_CIPHER 1
> +/* Chain any cipher with any hash or mac operation. The order
> + depends on the value of alg_chain_order param */
> +#define VIRTIO_CRYPTO_SYM_OP_ALGORITHM_CHAINING 2
> + le32 op_type;
> + le32 padding;
> +};
> +\end{lstlisting}
> +
> +\subparagraph{Session operation: AEAD session}\label{sec:Device Types /
> Crypto Device / Device
> +Operation / Control Virtqueue / Session operation / Session operation: AEAD
> session}
> +
> +The packet for AEAD session is as follows:
> +
> +\begin{lstlisting}
> +struct virtio_crypto_aead_session_para {
> + /* See VIRTIO_CRYPTO_AEAD_* above */
> + le32 algo;
> + /* length of key */
> + le32 key_len;
> + /* hash result length */
> + le32 hash_result_len;
> + /* The length of the additional authenticated data (AAD) in bytes */
> + le32 aad_len;
> + /* encryption or decryption, See above VIRTIO_CRYPTO_* */
> + le32 op;
> + le32 padding;
> +};
> +
> +struct virtio_crypto_aead_create_session_req {
> + /* Device-readable part */
> + struct virtio_crypto_aead_session_para para;
> + u8 key[key_len];
> +
> + /* Device-writeable part */
> + struct virtio_crypto_session_input input;
> +};
> +\end{lstlisting}
> +
> +\drivernormative{\subparagraph}{Session operation: create session}{Device
> Types / Crypto Device / Device Operation / Control Virtqueue / Session
> operation / Session operation: create session}
> +
> +\begin{itemize*}
> +\item The driver MUST set the control general header and corresponding
> properties of the union in structure virtio_crypto_op_ctrl_req. See
> \ref{sec:Device Types / Crypto Device / Device Operation / Control Virtqueue}.
> +\item The driver MUST set \field{opcode} field based on service type:
> CIPHER, HASH, MAC, or AEAD.
> +\item The driver MUST set \field{queue_id} field to show used dataq.
> +\end{itemize*}
> +
> +\devicenormative{\subparagraph}{Session operation: create session}{Device
> Types / Crypto Device / Device
> +Operation / Control Virtqueue / Session operation / Session operation:
> create session}
> +
> +\begin{itemize*}
> +\item The device MUST set \field{session_id} field as a session identifier
> return to the driver when the device finishes processing session creation.
> +\item The device MUST set \field{status} field to one of the values of enum
> VIRITO_CRYPTO_STATUS.
> +\end{itemize*}
> +
> +\drivernormative{\subparagraph}{Session operation: destroy session}{Device
> Types / Crypto Device / Device
> +Operation / Control Virtqueue / Session operation / Session operation:
> destroy session}
> +
> +\begin{itemize*}
> +\item The driver MUST set \field{opcode} field based on service type:
> CIPHER, HASH, MAC, or AEAD.
> +\item The driver MUST set the \field{session_id} to a valid value which
> assigned by the device when a session is created.
> +\end{itemize*}
> +
> +\devicenormative{\subparagraph}{Session operation: destroy session}{Device
> Types / Crypto Device / Device
> +Operation / Control Virtqueue / Session operation / Session operation:
> destroy session}
> +
> +\begin{itemize*}
> +\item The device MUST set \field{status} field to one of the values of enum
> VIRITO_CRYPTO_STATUS.
> +\end{itemize*}
> +
> +\subsubsection{Data Virtqueue}\label{sec:Device Types / Crypto Device /
> Device Operation / Data Virtqueue}
> +
> +The driver uses the data virtqueue to transmit the requests of crypto
> operation to the device,
> +and completes the data plane operations (such as crypto operation).
> +
> +The packet of dataq is as follows:
> +
> +\begin{lstlisting}
> +struct virtio_crypto_op_data_req {
> + struct virtio_crypto_op_header header;
> +
> + union {
> + struct virtio_crypto_sym_data_req sym_req;
> + struct virtio_crypto_hash_data_req hash_req;
> + struct virtio_crypto_mac_data_req mac_req;
> + struct virtio_crypto_aead_data_req aead_req;
> + } u;
> +};
> +\end{lstlisting}
> +
> +The header is the general header and the union is of the algorithm-specific
> type,
> +which is set by the driver. All properties in the union are shown as follows.
> +
> +There is a unified input header structure for all crypto services.
> +
> +The structure is defined as follows:
> +
> +\begin{lstlisting}
> +struct virtio_crypto_inhdr {
> + u8 status;
> +};
> +\end{lstlisting}
> +
> +\subsubsection{HASH Service Operation}\label{sec:Device Types / Crypto
> Device / Device Operation / HASH Service Operation}
> +
> +\begin{lstlisting}
> +struct virtio_crypto_hash_para {
> + /* length of source data */
> + le32 src_data_len;
> + /* hash result length */
> + le32 hash_result_len;
> +};
> +
> +struct virtio_crypto_hash_data_req {
> + /* Device-readable part */
> + struct virtio_crypto_hash_para para;
> + /* Source data */
> + u8 src_data[src_data_len];
> +
> + /* Device-writable part */
> + /* Hash result data */
> + u8 hash_result[hash_result_len];
> + struct virtio_crypto_inhdr inhdr;
> +};
> +\end{lstlisting}
> +
> +Each data request uses virtio_crypto_hash_data_req structure to store
> information
> +used to run the HASH operations.
> +
> +The information includes the hash parameters stored by \field{para}, output
> data and input data.
> +The output data here includes the source data and the input data includes
> the hash result data used to save the results of the HASH operations.
> +\field{inhdr} stores status of executing the HASH operations.
> +
> +\drivernormative{\paragraph}{HASH Service Operation}{Device Types / Crypto
> Device / Device Operation / HASH Service Operation}
> +
> +\begin{itemize*}
> +\item The driver MUST set the \field{session_id} in struct
> virtio_crypto_op_header to a valid value which assigned by the device when a
> session is created.
> +\item The driver MUST set \field{opcode} in struct virtio_crypto_op_header
> to VIRTIO_CRYPTO_HASH.
> +\item The driver MUST set the \field{queue_id} field to show used dataq in
> struct virtio_crypto_op_header.
> +\end{itemize*}
> +
> +\devicenormative{\paragraph}{HASH Service Operation}{Device Types / Crypto
> Device / Device Operation / HASH Service Operation}
> +
> +\begin{itemize*}
> +\item The device MUST copy the results of HASH operations to the
> hash_result[] if HASH operations success.
> +\item The device MUST set \field{status} in struct virtio_crypto_inhdr to
> one of the values of enum VIRITO_CRYPTO_STATUS.
> +\end{itemize*}
> +
> +\subsubsection{MAC Service Operation}\label{sec:Device Types / Crypto Device
> / Device Operation / MAC Service Operation}
> +
> +\begin{lstlisting}
> +struct virtio_crypto_mac_para {
> + struct virtio_crypto_hash_para hash;
> +};
> +
> +struct virtio_crypto_mac_data_req {
> + /* Device-readable part */
> + struct virtio_crypto_mac_para para;
> + /* Source data */
> + u8 src_data[src_data_len];
> +
> + /* Device-writable part */
> + /* Hash result data */
> + u8 hash_result[hash_result_len];
> + struct virtio_crypto_inhdr inhdr;
> +};
> +\end{lstlisting}
> +
> +Each data request uses virtio_crypto_mac_data_req structure to store
> information
> +used to run the MAC operations.
> +
> +The information includes the hash parameters stored by \field{para}, output
> data and input data.
> +The output data here includes the source data and the input data includes
> the hash result data used to save the results of the MAC operations.
> +\field{inhdr} stores status of executing the MAC operations.
> +
> +\drivernormative{\paragraph}{MAC Service Operation}{Device Types / Crypto
> Device / Device Operation / MAC Service Operation}
> +
> +\begin{itemize*}
> +\item The driver MUST set the \field{session_id} in struct
> virtio_crypto_op_header to a valid value which assigned by the device when a
> session is created.
> +\item The driver MUST set \field{opcode} in struct virtio_crypto_op_header
> to VIRTIO_CRYPTO_MAC.
> +\item The driver MUST set the \field{queue_id} field to show used dataq in
> struct virtio_crypto_op_header.
> +\end{itemize*}
> +
> +\devicenormative{\paragraph}{MAC Service Operation}{Device Types / Crypto
> Device / Device Operation / MAC Service Operation}
> +
> +\begin{itemize*}
> +\item The device MUST copy the results of MAC operations to the
> hash_result[] if HASH operations success.
> +\item The device MUST set \field{status} in struct virtio_crypto_inhdr to
> one of the values of enum VIRITO_CRYPTO_STATUS.
> +\end{itemize*}
> +
> +\subsubsection{Symmetric algorithms Operation}\label{sec:Device Types /
> Crypto Device / Device Operation / Symmetric algorithms Operation}
> +
> +The packet of plain CIPHER service is as follows:
> +
> +\begin{lstlisting}
> +struct virtio_crypto_cipher_para {
> + /*
> + * Byte Length of valid IV/Counter data pointed to by the below iv data.
> + *
> + * For block ciphers in CBC or F8 mode, or for Kasumi in F8 mode, or for
> + * SNOW3G in UEA2 mode, this is the length of the IV (which
> + * must be the same as the block length of the cipher).
> + * For block ciphers in CTR mode, this is the length of the counter
> + * (which must be the same as the block length of the cipher).
> + */
> + le32 iv_len;
> + /* length of source data */
> + le32 src_data_len;
> + /* length of destination data */
> + le32 dst_data_len;
> + le32 padding;
> +};
> +
> +struct virtio_crypto_cipher_data_req {
> + /* Device-readable part */
> + struct virtio_crypto_cipher_para para;
> + /*
> + * Initialization Vector or Counter data.
> + *
> + * For block ciphers in CBC or F8 mode, or for Kasumi in F8 mode, or for
> + * SNOW3G in UEA2 mode, this is the Initialization Vector (IV)
> + * value.
> + * For block ciphers in CTR mode, this is the counter.
> + * For AES-XTS, this is the 128bit tweak, i, from IEEE Std 1619-2007.
> + *
> + * The IV/Counter will be updated after every partial cryptographic
> + * operation.
> + */
> + u8 iv[iv_len];
> + /* Source data */
> + u8 src_data[src_data_len];
> +
> + /* Device-writable part */
> + /* Destination data */
> + u8 dst_data[dst_data_len];
> + struct virtio_crypto_inhdr inhdr;
> +};
> +\end{lstlisting}
> +
> +The packet of algorithm chaining is as follows:
> +
> +\begin{lstlisting}
> +struct virtio_crypto_alg_chain_data_para {
> + le32 iv_len;
> + /* Length of source data */
> + le32 src_data_len;
> + /* Length of destination data */
> + le32 dst_data_len;
> + /* Starting point for cipher processing in source data */
> + le32 cipher_start_src_offset;
> + /* Length of the source data that the cipher will be computed on */
> + le32 len_to_cipher;
> + /* Starting point for hash processing in source data */
> + le32 hash_start_src_offset;
> + /* Length of the source data that the hash will be computed on */
> + le32 len_to_hash;
> + /* Length of the additional auth data */
> + le32 aad_len;
> + /* Length of the hash result */
> + le32 hash_result_len;
> + le32 reserved;
> +};
> +
> +struct virtio_crypto_alg_chain_data_req {
> + /* Device-readable part */
> + struct virtio_crypto_alg_chain_data_para para;
> + /* Initialization Vector or Counter data */
> + u8 iv[iv_len];
> + /* Source data */
> + u8 src_data[src_data_len];
> + /* Additional authenticated data if exists */
> + u8 aad[aad_len];
> +
> + /* Device-writable part */
> + /* Destination data */
> + u8 dst_data[dst_data_len];
> + /* Hash result data */
> + u8 hash_result[hash_result_len];
> + struct virtio_crypto_inhdr inhdr;
> +};
> +\end{lstlisting}
> +
> +The packet of symmetric algorithm is as follows:
> +
> +\begin{lstlisting}
> +struct virtio_crypto_sym_data_req {
> + union {
> + struct virtio_crypto_cipher_data_req cipher;
> + struct virtio_crypto_alg_chain_data_req chain;
> + } u;
> +
> + /* Device-readable part */
> +
> + /* See above VIRTIO_CRYPTO_SYM_OP_* */
> + le32 op_type;
> + le32 padding;
> +};
> +\end{lstlisting}
> +
> +Each data request uses virtio_crypto_sym_data_req structure to store
> information
> +used to run the CIPHER operations.
> +
> +The information includes the hash parameters stored by \field{para}, output
> data and input data.
> +In the first virtio_crypto_cipher_para structure, \field{iv_len} specifies
> the length of the initialization vector or counter,
> +\field{src_data_len} specifies the length of the source data, and
> \field{dst_data_len} specifies the
> +length of the destination data.
> +For plain CIPHER operations, the output data here includes the IV/Counter
> data and source data, and the input data includes the destination data used
> to save the results of the CIPHER operations.
> +
> +For algorithms chain, the output data here includes the IV/Counter data,
> source data and additional authenticated data if exists.
> +The input data includes both destination data and hash result data used to
> store the results of the HASH/MAC operations.
> +\field{inhdr} stores status of executing the crypto operations.
> +
> +\drivernormative{\paragraph}{Symmetric algorithms Operation}{Device Types /
> Crypto Device / Device Operation / Symmetric algorithms Operation}
> +
> +\begin{itemize*}
> +\item The driver MUST set the \field{session_id} in struct
> virtio_crypto_op_header to a valid value which assigned by the device when a
> session is created.
> +\item The driver MUST set \field{opcode} in struct virtio_crypto_op_header
> to VIRTIO_CRYPTO_CIPHER_ENCRYPT or VIRTIO_CRYPTO_CIPHER_DECRYPT.
> +\item The driver MUST set the \field{queue_id} field to show used dataq in
> struct virtio_crypto_op_header.
> +\item The driver MUST specify the fields of struct
> virtio_crypto_cipher_data_req in struct virtio_crypto_sym_data_req if the
> created session is based on VIRTIO_CRYPTO_SYM_OP_CIPHER.
> +\item The driver MUST specify the fields of both struct
> virtio_crypto_cipher_data_req and struct virtio_crypto_mac_data_req in struct
> virtio_crypto_sym_data_req if the created session
> +\item is of the VIRTIO_CRYPTO_SYM_OP_ALGORITHM_CHAINING type and in the
> VIRTIO_CRYPTO_SYM_HASH_MODE_AUTH mode.
> +\end{itemize*}
> +
> +\devicenormative{\paragraph}{Symmetric algorithms Operation}{Device Types /
> Crypto Device / Device Operation / Symmetric algorithms Operation}
> +
> +\begin{itemize*}
> +\item The device MUST parse the virtio_crypto_sym_data_req based on the
> \field{opcode} in general header.
> +\item The device SHOULD only parse fields of struct
> virtio_crypto_cipher_data_req in struct virtio_crypto_sym_data_req if the
> created session is VIRTIO_CRYPTO_SYM_OP_CIPHER type.
> +\item The device MUST parse fields of both struct
> virtio_crypto_cipher_data_req and struct virtio_crypto_mac_data_req in struct
> virtio_crypto_sym_data_req if the created
> +session is of the VIRTIO_CRYPTO_SYM_OP_ALGORITHM_CHAINING operation type and
> in the VIRTIO_CRYPTO_SYM_HASH_MODE_AUTH mode.
> +\item The device MUST copy the result of cryptographic operation to the
> dst_data[] in both plain CIPHER mode and algorithms chain mode.
> +\item The device MUST check the \field{para}.\field{add_len} is bigger than
> 0 before parse the additional authenticated data in plain algorithms chain
> mode.
> +\item The device MUST copy the result of HASH/MAC operation to the
> hash_result[] is of the VIRTIO_CRYPTO_SYM_OP_ALGORITHM_CHAINING type.
> +\item The device MUST set the \field{status} field in struct
> virtio_crypto_inhdr to one of the values of enum VIRITO_CRYPTO_STATUS.
> +\end{itemize*}
> +
> +\paragraph{Steps of Operation}\label{sec:Device Types / Crypto Device /
> Device Operation / Symmetric algorithms Operation / Steps of Operation}
> +
> +\subparagraph{Step1: Create session}\label{sec:Device Types / Crypto Device
> / Device Operation / Symmetric algorithms Operation / Steps of Operation /
> Step1: Create session}
> +
> +\begin{enumerate}
> +\item The driver specifies information in struct virtio_crypto_op_ctrl_req,
> including the algorithm name, key, keylen etc;
> +\item The driver adds the request of session creation into the controlq's
> Vring Descriptor Table;
> +\item The driver kicks the device;
> +\item The device receives the request from controlq;
> +\item The device parses information about the request, and determines the
> information concerning the backend crypto accelerator;
> +\item The device packs information based on the APIs of the backend crypto
> accelerator;
> +\item The device invokes the session creation APIs of the backend crypto
> accelerator to create a session;
> +\item The device returns the session id to the driver.
> +\end{enumerate}
> +
> +\subparagraph{Step2: Execute cryptographic operation}\label{sec:Device Types
> / Crypto Device / Device Operation / Symmetric algorithms Operation / Steps
> of Operation / Step2: Execute cryptographic operation}
> +
> +\begin{enumerate}
> +\item The driver specifies information in struct virtio_crypto_op_data_req,
> including struct virtio_crypto_op_header and struct
> virtio_crypto_sym_data_req, see \ref{sec:Device Types / Crypto Device / Device
> + Operation / Symmetric algorithms Operation};
> +\item The driver adds the request for cryptographic operation into the
> dataq's Vring Descriptor Table;
> +\item The driver kicks the device (Or the device actively polls the dataq's
> Vring Descriptor Table);
> +\item The device receives the request from dataq;
> +\item The device parses information about the request, and determines the
> identification information for the backend crypto accelerator. For example,
> converting guest physical addresses to host physical addresses;
> +\item The device packs identification information based on the API of the
> backend crypto accelerator;
> +\item The device invokes the cryptographic APIs of the backend crypto
> accelerator;
> +\item The backend crypto accelerator executes the cryptographic operation
> implicitly;
> +\item The device receives the cryptographic results from the backend crypto
> accelerator (synchronous or asynchronous);
> +\item The device sets the \field{status} in struct virtio_crypto_inhdr;
> +\item The device updates and flushes the Used Ring to return the
> cryptographic results to the driver;
> +\item The device notifies the driver (Or the driver actively polls the
> dataq's Used Ring);
> +\item The driver saves the cryptographic result.
> +\end{enumerate}
> +
> +\begin{note}
> +\begin{itemize*}
> +\item For better performance, the device should by preference use vhost
> scheme (user space or kernel space)
> + as the backend crypto accelerator in the real production environment.
> +\end{itemize*}
> +\end{note}
> +
> +\subsubsection{AEAD Service Operation}\label{sec:Device Types / Crypto
> Device / Device Operation / AEAD Service Operation}
> +
> +\begin{lstlisting}
> +struct virtio_crypto_aead_para {
> + /*
> + * Byte Length of valid IV data.
> + *
> + * For GCM mode, this is either 12 (for 96-bit IVs) or 16, in which
> + * case iv points to J0.
> + * For CCM mode, this is the length of the nonce, which can be in the
> + * range 7 to 13 inclusive.
> + */
> + le32 iv_len;
> + /* length of additional auth data */
> + le32 aad_len;
> + /* length of source data */
> + le32 src_data_len;
> + /* length of dst data */
> + le32 dst_data_len;
> + /* Length of the hash result */
> + le32 hash_result_len;
> + le32 reserver;
> +};
> +
> +struct virtio_crypto_aead_data_req {
> + /* Device-readable part */
> + struct virtio_crypto_aead_para para;
> + /*
> + * Initialization Vector data.
> + *
> + * For GCM mode, this is either the IV (if the length is 96 bits) or J0
> + * (for other sizes), where J0 is as defined by NIST SP800-38D.
> + * Regardless of the IV length, a full 16 bytes needs to be allocated.
> + * For CCM mode, the first byte is reserved, and the nonce should be
> + * written starting at &iv[1] (to allow space for the implementation
> + * to write in the flags in the first byte). Note that a full 16 bytes
> + * should be allocated, even though the iv_len field will have
> + * a value less than this.
> + *
> + * The IV will be updated after every partial cryptographic operation.
> + */
> + u8 iv[iv_len];
> + /* Source data */
> + u8 src_data[src_data_len];
> + /* Additional authenticated data if exists */
> + u8 aad[aad_len];
> +
> + /* Device-writable part */
> + /* Destination data */
> + u8 dst_data[dst_data_len];
> + /* Hash result data */
> + u8 hash_result[hash_result_len];
> + struct virtio_crypto_inhdr inhdr;
> +};
> +\end{lstlisting}
> +
> +Each data request uses virtio_crypto_aead_data_req structure to store
> information
> +used to run the AEAD operations.
> +
> +The information includes the hash parameters stored by \field{para}, output
> data and input data.
> +In the first virtio_crypto_aead_para structure, \field{iv_len} specifies the
> length of the initialization vector.
> +\field{aad_len} specifies the length of additional authentication data,
> \field{src_data_len} specifies the
> +length of the source data; \field{dst_data_len} specifies the length of the
> destination data.
> +The output data here includes the IV data and source data, and the input
> data includes the destination data used to save the results of the CIPHER
> operations.
> +
> +The output data here includes the IV/Counter data, source data and
> additional authenticated data if exists.
> +The input data includes both destination data used to save the results of
> the AEAD operations.
> +\field{inhdr} stores status of executing the AEAD operations.
> +
> +\drivernormative{\paragraph}{AEAD Service Operation}{Device Types / Crypto
> Device / Device Operation / AEAD Service Operation}
> +
> +\begin{itemize*}
> +\item The driver MUST set the \field{session_id} in struct
> virtio_crypto_op_header to a valid value which assigned by the device when a
> session is created.
> +\item The driver MUST set \field{opcode} in struct virtio_crypto_op_header
> to VIRTIO_CRYPTO_AEAD_ENCRYPT or VIRTIO_CRYPTO_AEAD_DECRYPT.
> +\item The driver MUST set the \field{queue_id} field to show used dataq in
> struct virtio_crypto_op_header.
> +\end{itemize*}
> +
> +\devicenormative{\paragraph}{AEAD Service Operation}{Device Types / Crypto
> Device / Device Operation / AEAD Service Operation}
> +
> +\begin{itemize*}
> +\item The device MUST parse the virtio_crypto_aead_data_req based on the
> \field{opcode} in general header.
> +\item The device MUST copy the result of cryptographic operation to the
> dst_data[].
> +\item The device MUST copy the hash result to the hash_result[].
> +\item The device MUST set the \field{status} field in struct
> virtio_crypto_inhdr to one of the values of enum VIRITO_CRYPTO_STATUS.
> +\item When the \field{opcode} is VIRTIO_CRYPTO_AEAD_DECRYPT, the device MUST
> verify and return the verification result to the driver, and if the
> verification result is incorrect, VIRTIO_CRYPTO_BADMSG (bad message) MUST be
> returned to the driver.
> +\end{itemize*}
> \ No newline at end of file
>