Fapi_Sign(3)

💖 Fapi_Sign(3) — the sign-y one 💖

okay so bestie, welcome to Fapi_Sign from the Library Functions Manual ✨ this is the glow-up page for the TPM2 FAPI signing trio and honestly it ate 🫶

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🌈 NAME

Fapi_Sign — literally just Fapi_Sign 💅 (iconic, no notes)

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✨ SYNOPSIS

🎀 Functions

TSS2_RC Fapi_Sign (FAPI_CONTEXT *context, char const *keyPath, char
    const *padding, uint8_t const *digest, size_t digestSize, uint8_t
    **signature, size_t *signatureSize, char **publicKey, char
    **certificate)
TSS2_RC Fapi_Sign_Async (FAPI_CONTEXT *context, char const *keyPath,
    char const *padding, uint8_t const *digest, size_t digestSize)
TSS2_RC Fapi_Sign_Finish (FAPI_CONTEXT *context, uint8_t **signature,
    size_t *signatureSize, char **publicKey, char **certificate)

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🦋 Detailed Description

these are the FAPI functions that let you invoke Sign — you can do it as a one-call situation or in an asynchronous manner, whichever vibe you're on 💜

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👑 Function Documentation

🌸 TSS2_RC Fapi_Sign (...)

TSS2_RC Fapi_Sign (FAPI_CONTEXT * context, char const * keyPath, char const
    * padding, uint8_t const * digest, size_t digestSize, uint8_t **
    signature, size_t * signatureSize, char ** publicKey, char **
    certificate)

one-call function for Fapi_Sign ⭐

so it takes a key, identified by its path, and uses it to sign a digest, then puts the result in a TPM2B bytestream. slay 🔥

Parameters

• context — The FAPI_CONTEXT
• keyPath — The path of the signature key
• padding — A padding algorithm. Must be either "RSA_SSA" or "RSA_PSS" or NULL
• digest — The digest to sign. Must be already hashed
• digestSize — The size of the digest in bytes
• signature — The signature
• signatureSize — The size of signature in bytes. May be NULL
• publicKey — The public key that can be used to verify signature in PEM format. May be NULL
• certificate — The certificate associated with the signing key in PEM format. May be NULL

Return values

• TSS2_RC_SUCCESS if the function call was a success.
• TSS2_FAPI_RC_BAD_REFERENCE if context, keyPath, digest or signature is NULL.
• TSS2_FAPI_RC_BAD_CONTEXT if context corruption is detected.
• TSS2_FAPI_RC_KEY_NOT_FOUND if keyPath does not map to a FAPI key.
• TSS2_FAPI_RC_BAD_KEY if the object at keyPath is not a key, or is a key that is unsuitable for the requested operation.
• TSS2_FAPI_RC_BAD_VALUE if the digestSize is zero.
• TSS2_FAPI_RC_BAD_SEQUENCE if the context has an asynchronous operation already pending.
• TSS2_FAPI_RC_IO_ERROR if the data cannot be saved.
• TSS2_FAPI_RC_MEMORY if the FAPI cannot allocate enough memory for internal operations or return parameters.
• TSS2_FAPI_RC_NO_TPM if FAPI was initialized in no-TPM-mode via its config file.
• TSS2_FAPI_RC_TRY_AGAIN if an I/O operation is not finished yet and this function needs to be called again.
• TSS2_FAPI_RC_PATH_NOT_FOUND if a FAPI object path was not found during authorization.
• TSS2_FAPI_RC_GENERAL_FAILURE if an internal error occurred.
• TSS2_FAPI_RC_AUTHORIZATION_UNKNOWN if a required authorization callback is not set.
• TSS2_FAPI_RC_AUTHORIZATION_FAILED if the authorization attempt fails.
• TSS2_FAPI_RC_POLICY_UNKNOWN if policy search for a certain policy digest was not successful.
• TSS2_ESYS_RC_* possible error codes of ESAPI.
• TSS2_FAPI_RC_NOT_PROVISIONED FAPI was not provisioned.
• TSS2_FAPI_RC_BAD_PATH if the path is used in inappropriate context or contains illegal characters.

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🧚 TSS2_RC Fapi_Sign_Async (...)

TSS2_RC Fapi_Sign_Async (FAPI_CONTEXT * context, char const * keyPath, char
    const * padding, uint8_t const * digest, size_t digestSize)

asynchronous function for Fapi_Sign 🦋

same deal, bestie: uses a key, identified by its path, to sign a digest and puts the result in a TPM2B bytestream ✨

call Fapi_Sign_Finish to finish the execution of this command — don't leave it hanging, that's not the vibe 😭

Parameters

• context — The FAPI_CONTEXT
• keyPath — The path of the signature key
• padding — A padding algorithm. Must be either "RSA_SSA" or "RSA_PSS" or NULL
• digest — The digest to sign. Must be already hashed
• digestSize — The size of the digest in bytes

Return values

• TSS2_RC_SUCCESS if the function call was a success.
• TSS2_FAPI_RC_BAD_REFERENCE if context, keyPath or digest is NULL.
• TSS2_FAPI_RC_BAD_CONTEXT if context corruption is detected.
• TSS2_FAPI_RC_KEY_NOT_FOUND if keyPath does not map to a FAPI key.
• TSS2_FAPI_RC_BAD_KEY if the object at keyPath is not a key, or is a key that is unsuitable for the requested operation.
• TSS2_FAPI_RC_BAD_VALUE if the digestSize is zero.
• TSS2_FAPI_RC_BAD_SEQUENCE if the context has an asynchronous operation already pending.
• TSS2_FAPI_RC_IO_ERROR if the data cannot be saved.
• TSS2_FAPI_RC_MEMORY if the FAPI cannot allocate enough memory for internal operations or return parameters.
• TSS2_FAPI_RC_NO_TPM if FAPI was initialized in no-TPM-mode via its config file.

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💜 TSS2_RC Fapi_Sign_Finish (...)

TSS2_RC Fapi_Sign_Finish (FAPI_CONTEXT * context, uint8_t ** signature,
    size_t * signatureSize, char ** publicKey, char ** certificate)

asynchronous finish function for Fapi_Sign 🎀

this function should be called after a previous Fapi_Sign_Async — it's giving part two of the saga, main character energy 👑

Parameters

• context — The FAPI_CONTEXT
• signature — The signature
• signatureSize — The size of signature in bytes. May be NULL
• publicKey — The public key that can be used to verify signature in PEM format. May be NULL
• certificate — The certificate associated with the signing key in PEM format. May be NULL

Return values

• TSS2_RC_SUCCESS if the function call was a success.
• TSS2_FAPI_RC_BAD_REFERENCE if context or signature is NULL.
• TSS2_FAPI_RC_BAD_CONTEXT if context corruption is detected.
• TSS2_FAPI_RC_BAD_SEQUENCE if the context has an asynchronous operation already pending.
• TSS2_FAPI_RC_IO_ERROR if the data cannot be saved.
• TSS2_FAPI_RC_MEMORY if the FAPI cannot allocate enough memory for internal operations or return parameters.
• TSS2_FAPI_RC_TRY_AGAIN if the asynchronous operation is not yet complete. Call this function again later.
• TSS2_FAPI_RC_PATH_NOT_FOUND if a FAPI object path was not found during authorization.
• TSS2_FAPI_RC_KEY_NOT_FOUND if a key was not found.
• TSS2_FAPI_RC_BAD_VALUE if an invalid value was passed into the function.
• TSS2_FAPI_RC_GENERAL_FAILURE if an internal error occurred.
• TSS2_FAPI_RC_AUTHORIZATION_UNKNOWN if a required authorization callback is not set.
• TSS2_FAPI_RC_AUTHORIZATION_FAILED if the authorization attempt fails.
• TSS2_FAPI_RC_POLICY_UNKNOWN if policy search for a certain policy digest was not successful.
• TSS2_ESYS_RC_* possible error codes of ESAPI.
• TSS2_FAPI_RC_NOT_PROVISIONED FAPI was not provisioned.
• TSS2_FAPI_RC_BAD_PATH if the path is used in inappropriate context or contains illegal characters.

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🍓 Author

Generated automatically by Doxygen for tpm2-tss from the source code. (the bots wrote this one, we just gave it the sparkle treatment ✨🤖)

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mwah 💋 that's the whole page bestie — tpm2-tss, Version 4.1.5, dated Fapi_Sign(3). go sign something iconic 🫶🌈⭐