Sign with a private key. The key must be asymmetric and have the `SIGN` key operation enabled.

  • Published on Jul 22, 2025
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/crypto/v1/sign

Note: Signing prehashed data with LMS keys

When creating an LMS signature, the first step is to hash the message with a prefix that is unknown to the caller (see RFC8554, algorithm 3). As the caller cannot precompute this value, DSM follows different semantics for prehashed data. Namely, when the hash field is used, DSM will check the length of the digest and then feed it as raw data for the LMS signature generation.

Consequently, if you hash your data using an algorithm such as SHA256 and then supply this digest to the LMS signing API (putting prehashed data in the hash field), DSM interprets the provided digest as raw data, and verification of the signature should be conducted accordingly.

Security
HTTP
Type bearer
API Key: apiKeyAuth
Header parameter nameAuthorization
Body parameters
Expand All
object
key

Uniquely identifies a persisted or transient sobject.

OneOf
SobjectDescriptorVariantKid
object (SobjectDescriptorVariantKid)
kid
string (uuid) Required
SobjectDescriptorVariantName
object (SobjectDescriptorVariantName)
name
string Required
Max length4096
Pattern^[^\n]*[^\s\n][^\n]*$
SobjectDescriptorVariantTransientKey
object (SobjectDescriptorVariantTransientKey)
transient_key
string (byte) Required
SobjectDescriptorVariantInline
object (SobjectDescriptorVariantInline)
inline
object Required
value
string (byte) Required
obj_type
string Required

Type of security object.

Valid values[ "AES", "ARIA", "DES", "DES3", "SEED", "RSA", "DSA", "EC", "KCDSA", "ECKCDSA", "BIP32", "BLS", "OPAQUE", "HMAC", "LEDABETA", "ROUND5BETA", "SECRET", "LMS", "XMSS", "MLDSA", "MLDSABETA", "MLKEM", "MLKEMBETA", "CERTIFICATE", "PBE" ]
hash_alg
string

A hash algorithm.

Valid values[ "BLAKE2B256", "BLAKE2B384", "BLAKE2B512", "BLAKE2S256", "RIPEMD160", "SSL3", "SHA1", "SHA224", "SHA256", "SHA384", "SHA512", "STREEBOG256", "STREEBOG512", "SHA3_224", "SHA3_256", "SHA3_384", "SHA3_512" ]
hash
string (byte)

Hashed data to be signed. Either hash or data should be specified; it is an error to specify both or none. Hash should be base64 encoded.

data
string (byte)

Data to be signed. Either hash or data should be specified; it is an error to specify both or none. Data should be base64 encoded.

mode

Signature mechanism

OneOf
object
OneOf
RsaSignaturePaddingVariantPss
object (RsaSignaturePaddingVariantPss)
PSS
object Required
mgf

Specifies the Mask Generating Function (MGF) to use.

OneOf
MgfVariantMgf1
object (MgfVariantMgf1)
mgf1
object Required
hash
string Required

A hash algorithm.

Valid values[ "BLAKE2B256", "BLAKE2B384", "BLAKE2B512", "BLAKE2S256", "RIPEMD160", "SSL3", "SHA1", "SHA224", "SHA256", "SHA384", "SHA512", "STREEBOG256", "STREEBOG512", "SHA3_224", "SHA3_256", "SHA3_384", "SHA3_512" ]
RsaSignaturePaddingVariantPkcs1V15
object (RsaSignaturePaddingVariantPkcs1V15)
PKCS1_V15
object Required
deterministic_signature
boolean | null

Whether signatures should be deterministic. Defaults to false. If specified, the value must be compatible with the key's settings.

context
string (byte)

The context parameter to be provided to the sign algorithm.

Currently only ML-DSA keys accept a context parameter; this parameter must not be specified for any other key types.

Responses
2XX

Success result

object
kid
string (uuid) | null

The ID of the key used for signing. Returned for non-transient keys

signature
string (byte)

Signed data