rsa.h File Reference

This function checks if a context contains an RSA private key and perform basic consistency checks.

Parameters:

ctx	The RSA context to check.

Returns:

0 on success, or an MBEDTLS_ERR_RSA_XXX error code on failure.

Note:

The consistency checks performed by this function not only ensure that mbedtls_rsa_private() can be called successfully on the given context, but that the various parameters are mutually consistent with high probability, in the sense that mbedtls_rsa_public() and mbedtls_rsa_private() are inverses.

Warning:

This function should catch accidental misconfigurations like swapping of parameters, but it cannot establish full trust in neither the quality nor the consistency of the key material that was used to setup the given RSA context:

• Consistency: Imported parameters that are irrelevant for the implementation might be silently dropped. If dropped, the current function does not have access to them, and therefore cannot check them. See mbedtls_rsa_complete(). If you want to check the consistency of the entire content of an PKCS1-encoded RSA private key, for example, you should use mbedtls_rsa_validate_params() before setting up the RSA context. Additionally, if the implementation performs empirical checks, these checks substantiate but do not guarantee consistency.
• Quality: This function is not expected to perform extended quality assessments like checking that the prime factors are safe. Additionally, it is the responsibility of the user to ensure the trustworthiness of the source of his RSA parameters, which goes beyond what is effectively checkable by the library.

Definition at line 611 of file rsa.c.

This function checks a public-private RSA key pair.

It checks each of the contexts, and makes sure they match.

Parameters:

pub	The RSA context holding the public key.
prv	The RSA context holding the private key.

Returns:

0 on success, or an MBEDTLS_ERR_RSA_XXX error code on failure.

Definition at line 639 of file rsa.c.

This function checks if a context contains at least an RSA public key.

If the function runs successfully, it is guaranteed that enough information is present to perform an RSA public key operation using mbedtls_rsa_public().

Parameters:

ctx	The RSA context to check.

Returns:

0 on success, or an MBEDTLS_ERR_RSA_XXX error code on failure.

Definition at line 588 of file rsa.c.

This function completes an RSA context from a set of imported core parameters.

To setup an RSA public key, precisely N and E must have been imported.

To setup an RSA private key, sufficient information must be present for the other parameters to be derivable.

The default implementation supports the following:

• Derive P, Q from N, D, E.
• Derive N, D from P, Q, E.

Alternative implementations need not support these.

If this function runs successfully, it guarantees that the RSA context can be used for RSA operations without the risk of failure or crash.

Parameters:

ctx	The initialized RSA context holding imported parameters.

Returns:

0 on success, or MBEDTLS_ERR_RSA_BAD_INPUT_DATA if the attempted derivations failed.

Warning:

This function need not perform consistency checks for the imported parameters. In particular, parameters that are not needed by the implementation might be silently discarded and left unchecked. To check the consistency of the key material, see mbedtls_rsa_check_privkey().

Definition at line 242 of file rsa.c.

This function copies the components of an RSA context.

Parameters:

dst	The destination context.
src	The source context.

Returns:

0 on success, MBEDTLS_ERR_MPI_ALLOC_FAILED on memory allocation failure.

Definition at line 2057 of file rsa.c.

This function exports the core parameters of an RSA key.

If this function runs successfully, the non-NULL buffers pointed to by N, P, Q, D, and E are fully written, with additional unused space filled leading by zero Bytes.

Possible reasons for returning MBEDTLS_ERR_RSA_UNSUPPORTED_OPERATION:

• An alternative RSA implementation is in use, which stores the key externally, and either cannot or should not export it into RAM.
• A SW or HW implementation might not support a certain deduction. For example, P, Q from N, D, and E if the former are not part of the implementation.

If the function fails due to an unsupported operation, the RSA context stays intact and remains usable.

Parameters:

ctx	The initialized RSA context.
N	The MPI to hold the RSA modulus, or NULL.
P	The MPI to hold the first prime factor of N, or NULL.
Q	The MPI to hold the second prime factor of N, or NULL.
D	The MPI to hold the private exponent, or NULL.
E	The MPI to hold the public exponent, or NULL.

Returns:

0 on success, MBEDTLS_ERR_RSA_UNSUPPORTED_OPERATION if exporting the requested parameters cannot be done due to missing functionality or because of security policies, or a non-zero return code on any other failure.

Definition at line 379 of file rsa.c.

This function exports CRT parameters of a private RSA key.

Parameters:

ctx	The initialized RSA context.
DP	The MPI to hold D modulo P-1, or NULL.
DQ	The MPI to hold D modulo Q-1, or NULL.
QP	The MPI to hold modular inverse of Q modulo P, or NULL.

Returns:

0 on success, non-zero error code otherwise.

Note:

Alternative RSA implementations not using CRT-parameters internally can implement this function based on mbedtls_rsa_deduce_opt().

Definition at line 422 of file rsa.c.

This function exports core parameters of an RSA key in raw big-endian binary format.

If this function runs successfully, the non-NULL buffers pointed to by N, P, Q, D, and E are fully written, with additional unused space filled leading by zero Bytes.

Possible reasons for returning MBEDTLS_ERR_RSA_UNSUPPORTED_OPERATION:

• An alternative RSA implementation is in use, which stores the key externally, and either cannot or should not export it into RAM.
• A SW or HW implementation might not support a certain deduction. For example, P, Q from N, D, and E if the former are not part of the implementation.

If the function fails due to an unsupported operation, the RSA context stays intact and remains usable.

Parameters:

ctx	The initialized RSA context.
N	The Byte array to store the RSA modulus, or NULL.
N_len	The size of the buffer for the modulus.
P	The Byte array to hold the first prime factor of N, or NULL.
P_len	The size of the buffer for the first prime factor.
Q	The Byte array to hold the second prime factor of N, or NULL.
Q_len	The size of the buffer for the second prime factor.
D	The Byte array to hold the private exponent, or NULL.
D_len	The size of the buffer for the private exponent.
E	The Byte array to hold the public exponent, or NULL.
E_len	The size of the buffer for the public exponent.

Note:

The length fields are ignored if the corresponding buffer pointers are NULL.

Returns:

0 on success, MBEDTLS_ERR_RSA_UNSUPPORTED_OPERATION if exporting the requested parameters cannot be done due to missing functionality or because of security policies, or a non-zero return code on any other failure.

Definition at line 333 of file rsa.c.

This function frees the components of an RSA key.

Parameters:

ctx	The RSA Context to free.

Definition at line 2097 of file rsa.c.

This function generates an RSA keypair.

Parameters:

ctx	The RSA context used to hold the key.
f_rng	The RNG function.
p_rng	The RNG parameter.
nbits	The size of the public key in bits.
exponent	The public exponent. For example, 65537.

Note:

mbedtls_rsa_init() must be called before this function, to set up the RSA context.

Returns:

0 on success, or an MBEDTLS_ERR_RSA_XXX error code on failure.

Definition at line 497 of file rsa.c.

This function retrieves the length of RSA modulus in Bytes.

Parameters:

ctx	The initialized RSA context.

Returns:

The length of the RSA modulus in Bytes.

Definition at line 486 of file rsa.c.

This function imports a set of core parameters into an RSA context.

Parameters:

ctx	The initialized RSA context to store the parameters in.
N	The RSA modulus, or NULL.
P	The first prime factor of N, or NULL.
Q	The second prime factor of N, or NULL.
D	The private exponent, or NULL.
E	The public exponent, or NULL.

Note:

This function can be called multiple times for successive imports, if the parameters are not simultaneously present.

Any sequence of calls to this function should be followed by a call to mbedtls_rsa_complete(), which checks and completes the provided information to a ready-for-use public or private RSA key.

Note:

See mbedtls_rsa_complete() for more information on which parameters are necessary to set up a private or public RSA key.

The imported parameters are copied and need not be preserved for the lifetime of the RSA context being set up.

Returns:

0 on success, or a non-zero error code on failure.

Definition at line 92 of file rsa.c.

This function imports core RSA parameters, in raw big-endian binary format, into an RSA context.

Parameters:

ctx	The initialized RSA context to store the parameters in.
N	The RSA modulus, or NULL.
N_len	The Byte length of N, ignored if N == NULL.
P	The first prime factor of N, or NULL.
P_len	The Byte length of P, ignored if P == NULL.
Q	The second prime factor of N, or NULL.
Q_len	The Byte length of Q, ignored if Q == NULL.
D	The private exponent, or NULL.
D_len	The Byte length of D, ignored if D == NULL.
E	The public exponent, or NULL.
E_len	The Byte length of E, ignored if E == NULL.

Note:

This function can be called multiple times for successive imports, if the parameters are not simultaneously present.

Any sequence of calls to this function should be followed by a call to mbedtls_rsa_complete(), which checks and completes the provided information to a ready-for-use public or private RSA key.

Note:

See mbedtls_rsa_complete() for more information on which parameters are necessary to set up a private or public RSA key.

The imported parameters are copied and need not be preserved for the lifetime of the RSA context being set up.

Returns:

0 on success, or a non-zero error code on failure.

Definition at line 114 of file rsa.c.

This function initializes an RSA context.

Note:

Set padding to MBEDTLS_RSA_PKCS_V21 for the RSAES-OAEP encryption scheme and the RSASSA-PSS signature scheme.

Parameters:

ctx	The RSA context to initialize.
padding	Selects padding mode: MBEDTLS_RSA_PKCS_V15 or MBEDTLS_RSA_PKCS_V21.
hash_id	The hash identifier of mbedtls_md_type_t type, if padding is MBEDTLS_RSA_PKCS_V21.

Note:

The hash_id parameter is ignored when using MBEDTLS_RSA_PKCS_V15 padding.

The choice of padding mode is strictly enforced for private key operations, since there might be security concerns in mixing padding modes. For public key operations it is a default value, which can be overriden by calling specific rsa_rsaes_xxx or rsa_rsassa_xxx functions.

The hash selected in hash_id is always used for OEAP encryption. For PSS signatures, it is always used for making signatures, but can be overriden for verifying them. If set to MBEDTLS_MD_NONE, it is always overriden.

Definition at line 460 of file rsa.c.

This function performs an RSA operation, then removes the message padding.

It is the generic wrapper for performing a PKCS#1 decryption operation using the mode from the context.

Parameters:

ctx	The RSA context.
f_rng	The RNG function. Only needed for MBEDTLS_RSA_PRIVATE.
p_rng	The RNG parameter.
mode	MBEDTLS_RSA_PUBLIC or MBEDTLS_RSA_PRIVATE.
olen	The length of the plaintext.
input	The buffer holding the encrypted data.
output	The buffer used to hold the plaintext.
output_max_len	The maximum length of the output buffer.

Note:

Alternative implementations of RSA need not support mode being set to MBEDTLS_RSA_PUBLIC and might instead return MBEDTLS_ERR_RSA_UNSUPPORTED_OPERATION.

Returns:

0 on success, or an MBEDTLS_ERR_RSA_XXX error code on failure.

Note:

The output buffer length output_max_len should be as large as the size ctx->len of ctx->N (for example, 128 Bytes if RSA-1024 is used) to be able to hold an arbitrary decrypted message. If it is not large enough to hold the decryption of the particular ciphertext provided, the function returns MBEDTLS_ERR_RSA_OUTPUT_TOO_LARGE.

The input buffer must be as large as the size of ctx->N. For example, 128 Bytes if RSA-1024 is used.

Definition at line 1408 of file rsa.c.

This function adds the message padding, then performs an RSA operation.

It is the generic wrapper for performing a PKCS#1 encryption operation using the mode from the context.

Parameters:

ctx	The RSA context.
f_rng	The RNG function. Needed for padding, PKCS#1 v2.1 encoding, and MBEDTLS_RSA_PRIVATE.
p_rng	The RNG parameter.
mode	MBEDTLS_RSA_PUBLIC or MBEDTLS_RSA_PRIVATE.
ilen	The length of the plaintext.
input	The buffer holding the data to encrypt.
output	The buffer used to hold the ciphertext.

Note:

Alternative implementations of RSA need not support mode being set to MBEDTLS_RSA_PRIVATE and might instead return MBEDTLS_ERR_RSA_UNSUPPORTED_OPERATION.

Returns:

0 on success, or an MBEDTLS_ERR_RSA_XXX error code on failure.

Note:

The input and output buffers must be as large as the size of ctx->N. For example, 128 Bytes if RSA-1024 is used.

Definition at line 1144 of file rsa.c.

This function performs a private RSA operation to sign a message digest using PKCS#1.

It is the generic wrapper for performing a PKCS#1 signature using the mode from the context.

Parameters:

ctx	The RSA context.
f_rng	The RNG function. Needed for PKCS#1 v2.1 encoding and for MBEDTLS_RSA_PRIVATE.
p_rng	The RNG parameter.
mode	MBEDTLS_RSA_PUBLIC or MBEDTLS_RSA_PRIVATE.
md_alg	The message-digest algorithm used to hash the original data. Use MBEDTLS_MD_NONE for signing raw data.
hashlen	The length of the message digest. Only used if md_alg is MBEDTLS_MD_NONE.
hash	The buffer holding the message digest.
sig	The buffer to hold the ciphertext.

Note:

Alternative implementations of RSA need not support mode being set to MBEDTLS_RSA_PUBLIC and might instead return MBEDTLS_ERR_RSA_UNSUPPORTED_OPERATION.

Returns:

0 if the signing operation was successful, or an MBEDTLS_ERR_RSA_XXX error code on failure.

Note:

The sig buffer must be as large as the size of ctx->N. For example, 128 Bytes if RSA-1024 is used.

For PKCS#1 v2.1 encoding, see comments on mbedtls_rsa_rsassa_pss_sign() for details on md_alg and hash_id.

Definition at line 1754 of file rsa.c.

This function performs a public RSA operation and checks the message digest.

This is the generic wrapper for performing a PKCS#1 verification using the mode from the context.

Parameters:

ctx	The RSA public key context.
f_rng	The RNG function. Only needed for MBEDTLS_RSA_PRIVATE.
p_rng	The RNG parameter.
mode	MBEDTLS_RSA_PUBLIC or MBEDTLS_RSA_PRIVATE.
md_alg	The message-digest algorithm used to hash the original data. Use MBEDTLS_MD_NONE for signing raw data.
hashlen	The length of the message digest. Only used if md_alg is MBEDTLS_MD_NONE.
hash	The buffer holding the message digest.
sig	The buffer holding the ciphertext.

Note:

Alternative implementations of RSA need not support mode being set to MBEDTLS_RSA_PRIVATE and might instead return MBEDTLS_ERR_RSA_UNSUPPORTED_OPERATION.

Returns:

0 if the verify operation was successful, or an MBEDTLS_ERR_RSA_XXX error code on failure.

Note:

The sig buffer must be as large as the size of ctx->N. For example, 128 Bytes if RSA-1024 is used.

For PKCS#1 v2.1 encoding, see comments on mbedtls_rsa_rsassa_pss_verify() about md_alg and hash_id.

Definition at line 2026 of file rsa.c.

This function performs an RSA private key operation.

Parameters:

ctx	The RSA context.
f_rng	The RNG function. Needed for blinding.
p_rng	The RNG parameter.
input	The input buffer.
output	The output buffer.

Returns:

0 on success, or an MBEDTLS_ERR_RSA_XXX error code on failure.

Note:

The input and output buffers must be large enough. For example, 128 Bytes if RSA-1024 is used.

Definition at line 768 of file rsa.c.

This function performs an RSA public key operation.

Parameters:

ctx	The RSA context.
input	The input buffer.
output	The output buffer.

Returns:

0 on success, or an MBEDTLS_ERR_RSA_XXX error code on failure.

Note:

This function does not handle message padding.

Make sure to set input[0] = 0 or ensure that input is smaller than N.

The input and output buffers must be large enough. For example, 128 Bytes if RSA-1024 is used.

Definition at line 660 of file rsa.c.

This function performs a PKCS#1 v2.1 OAEP decryption operation (RSAES-OAEP-DECRYPT).

Parameters:

ctx	The RSA context.
f_rng	The RNG function. Only needed for MBEDTLS_RSA_PRIVATE.
p_rng	The RNG parameter.
mode	MBEDTLS_RSA_PUBLIC or MBEDTLS_RSA_PRIVATE.
label	The buffer holding the custom label to use.
label_len	The length of the label.
olen	The length of the plaintext.
input	The buffer holding the encrypted data.
output	The buffer to hold the plaintext.
output_max_len	The maximum length of the output buffer.

Note:

Alternative implementations of RSA need not support mode being set to MBEDTLS_RSA_PUBLIC and might instead return MBEDTLS_ERR_RSA_UNSUPPORTED_OPERATION.

Returns:

0 on success, or an MBEDTLS_ERR_RSA_XXX error code on failure.

Note:

The output buffer length output_max_len should be as large as the size ctx->len of ctx->N, for example, 128 Bytes if RSA-1024 is used, to be able to hold an arbitrary decrypted message. If it is not large enough to hold the decryption of the particular ciphertext provided, the function returns MBEDTLS_ERR_RSA_OUTPUT_TOO_LARGE.

The input buffer must be as large as the size of ctx->N. For example, 128 Bytes if RSA-1024 is used.

Definition at line 1174 of file rsa.c.

This function performs a PKCS#1 v2.1 OAEP encryption operation (RSAES-OAEP-ENCRYPT).

Parameters:

ctx	The RSA context.
f_rng	The RNG function. Needed for padding and PKCS#1 v2.1 encoding and MBEDTLS_RSA_PRIVATE.
p_rng	The RNG parameter.
mode	MBEDTLS_RSA_PUBLIC or MBEDTLS_RSA_PRIVATE.
label	The buffer holding the custom label to use.
label_len	The length of the label.
ilen	The length of the plaintext.
input	The buffer holding the data to encrypt.
output	The buffer used to hold the ciphertext.

Note:

Alternative implementations of RSA need not support mode being set to MBEDTLS_RSA_PRIVATE and might instead return MBEDTLS_ERR_RSA_UNSUPPORTED_OPERATION.

Returns:

0 on success, or an MBEDTLS_ERR_RSA_XXX error code on failure.

Note:

The output buffer must be as large as the size of ctx->N. For example, 128 Bytes if RSA-1024 is used.

Definition at line 997 of file rsa.c.

This function performs a PKCS#1 v1.5 decryption operation (RSAES-PKCS1-v1_5-DECRYPT).

Parameters:

ctx	The RSA context.
f_rng	The RNG function. Only needed for MBEDTLS_RSA_PRIVATE.
p_rng	The RNG parameter.
mode	MBEDTLS_RSA_PUBLIC or MBEDTLS_RSA_PRIVATE.
olen	The length of the plaintext.
input	The buffer holding the encrypted data.
output	The buffer to hold the plaintext.
output_max_len	The maximum length of the output buffer.

Note:

Alternative implementations of RSA need not support mode being set to MBEDTLS_RSA_PUBLIC and might instead return MBEDTLS_ERR_RSA_UNSUPPORTED_OPERATION.

Returns:

0 on success, or an MBEDTLS_ERR_RSA_XXX error code on failure.

Note:

The output buffer length output_max_len should be as large as the size ctx->len of ctx->N, for example, 128 Bytes if RSA-1024 is used, to be able to hold an arbitrary decrypted message. If it is not large enough to hold the decryption of the particular ciphertext provided, the function returns MBEDTLS_ERR_RSA_OUTPUT_TOO_LARGE.

The input buffer must be as large as the size of ctx->N. For example, 128 Bytes if RSA-1024 is used.

Definition at line 1312 of file rsa.c.

This function performs a PKCS#1 v1.5 encryption operation (RSAES-PKCS1-v1_5-ENCRYPT).

Parameters:

ctx	The RSA context.
f_rng	The RNG function. Needed for padding and MBEDTLS_RSA_PRIVATE.
p_rng	The RNG parameter.
mode	MBEDTLS_RSA_PUBLIC or MBEDTLS_RSA_PRIVATE.
ilen	The length of the plaintext.
input	The buffer holding the data to encrypt.
output	The buffer used to hold the ciphertext.

Note:

Alternative implementations of RSA need not support mode being set to MBEDTLS_RSA_PRIVATE and might instead return MBEDTLS_ERR_RSA_UNSUPPORTED_OPERATION.

Returns:

0 on success, or an MBEDTLS_ERR_RSA_XXX error code on failure.

Note:

The output buffer must be as large as the size of ctx->N. For example, 128 Bytes if RSA-1024 is used.

Definition at line 1078 of file rsa.c.

This function performs a PKCS#1 v1.5 signature operation (RSASSA-PKCS1-v1_5-SIGN).

Parameters:

ctx	The RSA context.
f_rng	The RNG function. Only needed for MBEDTLS_RSA_PRIVATE.
p_rng	The RNG parameter.
mode	MBEDTLS_RSA_PUBLIC or MBEDTLS_RSA_PRIVATE.
md_alg	The message-digest algorithm used to hash the original data. Use MBEDTLS_MD_NONE for signing raw data.
hashlen	The length of the message digest. Only used if md_alg is MBEDTLS_MD_NONE.
hash	The buffer holding the message digest.
sig	The buffer to hold the ciphertext.

Note:

Alternative implementations of RSA need not support mode being set to MBEDTLS_RSA_PUBLIC and might instead return MBEDTLS_ERR_RSA_UNSUPPORTED_OPERATION.

Returns:

0 if the signing operation was successful, or an MBEDTLS_ERR_RSA_XXX error code on failure.

Note:

The sig buffer must be as large as the size of ctx->N. For example, 128 Bytes if RSA-1024 is used.

Definition at line 1682 of file rsa.c.

This function performs a PKCS#1 v1.5 verification operation (RSASSA-PKCS1-v1_5-VERIFY).

Parameters:

ctx	The RSA public key context.
f_rng	The RNG function. Only needed for MBEDTLS_RSA_PRIVATE.
p_rng	The RNG parameter.
mode	MBEDTLS_RSA_PUBLIC or MBEDTLS_RSA_PRIVATE.
md_alg	The message-digest algorithm used to hash the original data. Use MBEDTLS_MD_NONE for signing raw data.
hashlen	The length of the message digest. Only used if md_alg is MBEDTLS_MD_NONE.
hash	The buffer holding the message digest.
sig	The buffer holding the ciphertext.

Note:

Alternative implementations of RSA need not support mode being set to MBEDTLS_RSA_PRIVATE and might instead return MBEDTLS_ERR_RSA_UNSUPPORTED_OPERATION.

Returns:

0 if the verify operation was successful, or an MBEDTLS_ERR_RSA_XXX error code on failure.

Note:

The sig buffer must be as large as the size of ctx->N. For example, 128 Bytes if RSA-1024 is used.

Definition at line 1953 of file rsa.c.

This function performs a PKCS#1 v2.1 PSS signature operation (RSASSA-PSS-SIGN).

Parameters:

ctx	The RSA context.
f_rng	The RNG function. Needed for PKCS#1 v2.1 encoding and for MBEDTLS_RSA_PRIVATE.
p_rng	The RNG parameter.
mode	MBEDTLS_RSA_PUBLIC or MBEDTLS_RSA_PRIVATE.
md_alg	The message-digest algorithm used to hash the original data. Use MBEDTLS_MD_NONE for signing raw data.
hashlen	The length of the message digest. Only used if md_alg is MBEDTLS_MD_NONE.
hash	The buffer holding the message digest.
sig	The buffer to hold the ciphertext.

Note:

Alternative implementations of RSA need not support mode being set to MBEDTLS_RSA_PUBLIC and might instead return MBEDTLS_ERR_RSA_UNSUPPORTED_OPERATION.

Returns:

0 if the signing operation was successful, or an MBEDTLS_ERR_RSA_XXX error code on failure.

Note:

The sig buffer must be as large as the size of ctx->N. For example, 128 Bytes if RSA-1024 is used.

The hash_id in the RSA context is the one used for the encoding. md_alg in the function call is the type of hash that is encoded. According to RFC-3447: Public-Key Cryptography Standards (PKCS) #1 v2.1: RSA Cryptography Specifications it is advised to keep both hashes the same.

Definition at line 1440 of file rsa.c.

This function performs a PKCS#1 v2.1 PSS verification operation (RSASSA-PSS-VERIFY).

The hash function for the MGF mask generating function is that specified in the RSA context.

Parameters:

ctx	The RSA public key context.
f_rng	The RNG function. Only needed for MBEDTLS_RSA_PRIVATE.
p_rng	The RNG parameter.
mode	MBEDTLS_RSA_PUBLIC or MBEDTLS_RSA_PRIVATE.
md_alg	The message-digest algorithm used to hash the original data. Use MBEDTLS_MD_NONE for signing raw data.
hashlen	The length of the message digest. Only used if md_alg is MBEDTLS_MD_NONE.
hash	The buffer holding the message digest.
sig	The buffer holding the ciphertext.

Note:

Alternative implementations of RSA need not support mode being set to MBEDTLS_RSA_PRIVATE and might instead return MBEDTLS_ERR_RSA_UNSUPPORTED_OPERATION.

Returns:

0 if the verify operation was successful, or an MBEDTLS_ERR_RSA_XXX error code on failure.

Note:

The sig buffer must be as large as the size of ctx->N. For example, 128 Bytes if RSA-1024 is used.

The hash_id in the RSA context is the one used for the verification. md_alg in the function call is the type of hash that is verified. According to RFC-3447: Public-Key Cryptography Standards (PKCS) #1 v2.1: RSA Cryptography Specifications it is advised to keep both hashes the same. If hash_id in the RSA context is unset, the md_alg from the function call is used.

Definition at line 1928 of file rsa.c.

This function performs a PKCS#1 v2.1 PSS verification operation (RSASSA-PSS-VERIFY).

The hash function for the MGF mask generating function is that specified in mgf1_hash_id.

Parameters:

ctx	The RSA public key context.
f_rng	The RNG function. Only needed for MBEDTLS_RSA_PRIVATE.
p_rng	The RNG parameter.
mode	MBEDTLS_RSA_PUBLIC or MBEDTLS_RSA_PRIVATE.
md_alg	The message-digest algorithm used to hash the original data. Use MBEDTLS_MD_NONE for signing raw data.
hashlen	The length of the message digest. Only used if md_alg is MBEDTLS_MD_NONE.
hash	The buffer holding the message digest.
mgf1_hash_id	The message digest used for mask generation.
expected_salt_len	The length of the salt used in padding. Use MBEDTLS_RSA_SALT_LEN_ANY to accept any salt length.
sig	The buffer holding the ciphertext.

Returns:

0 if the verify operation was successful, or an MBEDTLS_ERR_RSA_XXX error code on failure.

Note:

The sig buffer must be as large as the size of ctx->N. For example, 128 Bytes if RSA-1024 is used.

The hash_id in the RSA context is ignored.

Definition at line 1786 of file rsa.c.

The RSA checkup routine.

Returns:

0 on success, or 1 on failure.

Definition at line 2185 of file rsa.c.

This function sets padding for an already initialized RSA context.

See mbedtls_rsa_init() for details.

Parameters:

ctx	The RSA context to be set.
padding	Selects padding mode: MBEDTLS_RSA_PKCS_V15 or MBEDTLS_RSA_PKCS_V21.
hash_id	The MBEDTLS_RSA_PKCS_V21 hash identifier.

Definition at line 476 of file rsa.c.