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NAME |SYNOPSIS |DESCRIPTION |ARGUMENTS |RETURN VALUE |SEE ALSO |AUTHORS |COLOPHON | |
mlx5dv_dek_cre...5dv_dek_destroy(3)mlx5dv_dek_cre...5dv_dek_destroy(3)mlx5dv_dek_create - Creates a DEK mlx5dv_dek_query - Queries a DEK’s attributes mlx5dv_dek_destroy - Destroys a DEK
#include <infiniband/mlx5dv.h> struct mlx5dv_dek *mlx5dv_dek_create(struct ibv_context *context, struct mlx5dv_dek_init_attr *init_attr); int mlx5dv_dek_query(struct mlx5dv_dek *dek, struct mlx5dv_dek_attr *attr); int mlx5dv_dek_destroy(struct mlx5dv_dek *dek);
Data Encryption Keys (DEKs) are used to encrypt and decrypt transmitted data. After a DEK is created, it can be configured in MKeys for crypto offload operations. DEKs are not persistent and are destroyed upon process exit. Therefore, software process needs to re-create all needed DEKs on startup.mlx5dv_dek_create()creates a new DEK with the attributes specified ininit_attr. A pointer to the newly created dek is returned, which can be used for DEK query, DEK destruction and when configuring a MKey for crypto offload operations. The DEK can be either wrapped or in plaintext and the format that should be used is determined by the specified crypto_login object. To create a wrapped DEK, the application must have a valid crypto login object prior to creating the DEK. Creating a wrapped DEK can be performed in two ways: 1. Callmlx5dv_crypto_login_create()to obtain a crypto login object. Indicate that the DEK is wrapped by settingMLX5DV_DEK_INIT_ATTR_CRYPTO_LOGINvalue incomp_mask and passing the crypto login object incrypto_login field ofinit_attr. Fill the other DEK attributes and create the DEK. 2. Callmlx5dv_crypto_login()i.e., the old API. Supply credential, import_kek_id To create a plaintext DEK, the application must indicate that the DEK is in plaintext by settingMLX5DV_DEK_INIT_ATTR_CRYPTO_LOGIN value incomp_mask and passing NULL value incrypto_login field ofinit_attr, fill the other DEK attributes and create the DEK. To use the created DEK (either wrapped or plaintext) in a MKey, a valid crypto login object or session is not needed. Revoking the import KEK or credential that were used for the crypto login object or session (and therefore rendering the crypto login invalid) does not prevent using a created DEK.mlx5dv_dek_query()queries the DEK specified bydek and returns the queried attributes inattr. A valid crypto login object or session is not required to query a plaintext DEK. On the other hand, to query a wrapped DEK a valid crypto login object or session must be present.mlx5dv_dek_destroy()destroys the DEK specified bydek.
context The device context to create the DEK with.init_attr enum mlx5dv_dek_init_attr_mask { MLX5DV_DEK_INIT_ATTR_CRYPTO_LOGIN = 1 << 0, }; struct mlx5dv_dek_init_attr { enum mlx5dv_crypto_key_size key_size; bool has_keytag; enum mlx5dv_crypto_key_purpose key_purpose; struct ibv_pd *pd; char opaque[8]; char key[128]; uint64_t comp_mask; /* Use enum mlx5dv_dek_init_attr_mask */ struct mlx5dv_crypto_login_obj *crypto_login; };key_size The size of the key, can be one of the followingMLX5DV_CRYPTO_KEY_SIZE_128 Key size is 128 bit.MLX5DV_CRYPTO_KEY_SIZE_256 Key size is 256 bit.has_keytag Whether the DEK has a keytag or not. If set, the key should include a 8 Bytes keytag. Keytag is used to verify that the DEK being used by a MKey is the expected DEK. This is done by comparing the keytag that was defined during DEK creation with the keytag provided in the MKey crypto configuration, and failing the operation if they are different.key_purpose The purpose of the key, currently can only be the following valueMLX5DV_CRYPTO_KEY_PURPOSE_AES_XTS The key will be used for AES-XTS crypto engine.pd The protection domain to be associated with the DEK.opaque Plaintext metadata to describe the key.key The key that will be used for encryption and decryption of transmitted data. For plaintext DEKkey must be provided in plaintext. For wrapped DEKkey must be provided wrapped by the import KEK that was specified in the crypto login. Actual size and layout of this field depend on the providedkey_size andhas_keytag fields, as well as on the format of the key (plaintext or wrapped).key should be constructed according to the following table. DEKkey Field Construction. Import Has Keytag Key size Key Layout Method ──────────────────────────────────────────────────────────────────────────────── Plaintext No 128 Bit key1_128b + key2_128b Plaintext No 256 Bit key1_256b + key2_256b Plaintext Yes 128 Bit key1_128b + key2_128b + keytag_64b Plaintext Yes 256 Bit key1_256b + key2_256b + keytag_64b Wrapped No 128 Bit ENC(iv_64b + key1_128b + key2_128b) Wrapped No 256 Bit ENC(iv_64b + key1_256b + key2_256b) Wrapped Yes 128 Bit ENC(iv_64b + key1_128b + key2_128b + keytag_64b) Wrapped Yes 256 Bit ENC(iv_64b + key1_256b + key2_256b + keytag_64b) Where ENC() is AES key wrap algorithm and iv_64b is 0xA6A6A6A6A6A6A6A6 as per the NIST SP 800-38F AES key wrap spec. The following example shows how to wrap a 128 bit key that has keytag using a 128 bit import KEK in OpenSSL: #include <openssl/evp.h> unsigned char import_kek[16]; /* 128 bit import KEK in plaintext for wrapping */ unsigned char iv[8] = {0xA6, 0xA6, 0xA6, 0xA6, 0xA6, 0xA6, 0xA6, 0xA6}; /* * Indexes 0-15 are key1 in plaintext, indexes 16-31 are key2 in plaintext, * and indexes 32-39 are key_tag in plaintext. */ unsigned char key[40]; unsigned char wrapped_key[48]; EVP_CIPHER_CTX *ctx; int len; ctx = EVP_CIPHER_CTX_new(); EVP_CIPHER_CTX_set_flags(ctx, EVP_CIPHER_CTX_FLAG_WRAP_ALLOW); EVP_EncryptInit_ex(ctx, EVP_aes_128_wrap(), NULL, import_kek, iv); EVP_EncryptUpdate(ctx, wrapped_key, &len, key, sizeof(key)); EVP_EncryptFinal_ex(ctx, wrapped_key + len, &len); EVP_CIPHER_CTX_free(ctx);comp_mask Currently can be the following value:MLX5DV_DEK_INIT_ATTR_CRYPTO_LOGIN, which indicates thatcrypto_login field is applicable.crypto_login Pointer to a crypto login object. If set to a valid crypto login object, indicates that this is a wrapped DEK that will be created using the given crypto login object. If set to NULL, indicates that this is a plaintext DEK. Must be NULL ifMLX5DV_DEK_INIT_ATTR_CRYPTO_LOGINis not set. Only relevant when comp_mask is set withMLX5DV_DEK_INIT_ATTR_CRYPTO_LOGINdek Pointer to an existing DEK to query or to destroy.attr DEK attributes to be populated when querying a DEK. struct mlx5dv_dek_attr { enum mlx5dv_dek_state state; char opaque[8]; uint64_t comp_mask; };state The state of the DEK, can be one of the followingMLX5DV_DEK_STATE_READY The key is ready for use. This is the state of the key when it is first created.MLX5DV_DEK_STATE_ERROR The key is unusable. The key needs to be destroyed and re-created in order to be used. This can happen, for example, due to DEK memory corruption.opaque Plaintext metadata to describe the key.comp_mask Reserved for future extension, must be 0 now.mlx5dv_dek_create()returns a pointer to a newstruct mlx5dv_dek on success. On error NULL is returned and errno is set.mlx5dv_dek_query()returns 0 on success and updatesattr with the queried DEK attributes. On error errno value is returned.mlx5dv_dek_destroy()returns 0 on success and errno value on error.
mlx5dv_crypto_login(3),mlx5dv_crypto_login_create(3),mlx5dv_query_device(3)
Avihai Horon ⟨avihaih@nvidia.com⟩
This page is part of therdma-core (RDMA Core Userspace Libraries and Daemons) project. Information about the project can be found at ⟨https://github.com/linux-rdma/rdma-core⟩. If you have a bug report for this manual page, send it to linux-rdma@vger.kernel.org. This page was obtained from the project's upstream Git repository ⟨https://github.com/linux-rdma/rdma-core.git⟩ on 2025-08-11. (At that time, the date of the most recent commit that was found in the repository was 2025-08-04.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which isnot part of the original manual page), send a mail to man-pages@man7.orgmlx5dv_dek_cre...5dv_dek_destroy(3)HTML rendering created 2025-09-06 byMichael Kerrisk, author ofThe Linux Programming Interface. For details of in-depthLinux/UNIX system programming training courses that I teach, lookhere. Hosting byjambit GmbH. | |