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ASN.1

Functions

Name
int wc_InitCert(Cert * )
This function initializes a default cert, with the default options: version = 3 (0x2), serial = 0, sigType = SHA_WITH_RSA, issuer = blank, daysValid = 500, selfSigned = 1 (true) use subject as issuer, subject = blank.
int wc_MakeCert(Cert * cert, byte * derBuffer, word32 derSz, RsaKey * rsaKey, ecc_key * eccKey, WC_RNG * rng)
Used to make CA signed certs. Called after the subject information has been entered. This function makes an x509 Certificate v3 RSA or ECC from a cert input. It then writes this cert to derBuffer. It takes in either an rsaKey or an eccKey to generate the certificate. The certificate must be initialized with wc_InitCert before this method is called.
int wc_MakeCertReq(Cert * cert, byte * derBuffer, word32 derSz, RsaKey * rsaKey, ecc_key * eccKey)
This function makes a certificate signing request using the input certificate and writes the output to derBuffer. It takes in either an rsaKey or an eccKey to generate the certificate request. wc_SignCert() will need to be called after this function to sign the certificate request. Please see the wolfCrypt test application (./wolfcrypt/test/test.c) for an example usage of this function.
int wc_SignCert(int requestSz, int sigType, byte * derBuffer, word32 derSz, RsaKey * rsaKey, ecc_key * eccKey, WC_RNG * rng)
This function signs buffer and adds the signature to the end of buffer. It takes in a signature type. Must be called after wc_MakeCert() or wc_MakeCertReq() if creating a CA signed cert.
int wc_MakeSelfCert(Cert * cert, byte * derBuffer, word32 derSz, RsaKey * key, WC_RNG * rng)
This function is a combination of the previous two functions, wc_MakeCert and wc_SignCert for self signing (the previous functions may be used for CA requests). It makes a certificate, and then signs it, generating a self-signed certificate.
int wc_SetIssuer(Cert * cert, const char * issuerFile)
This function sets the issuer for a certificate to the issuer in the provided pem issuerFile. It also changes the certificate’s self-signed attribute to false. The issuer specified in issuerFile is verified prior to setting the cert issuer. This method is used to set fields prior to signing.
int wc_SetSubject(Cert * cert, const char * subjectFile)
This function sets the subject for a certificate to the subject in the provided pem subjectFile. This method is used to set fields prior to signing.
int wc_SetSubjectRaw(Cert * cert, const byte * der, int derSz)
This function sets the raw subject for a certificate from the subject in the provided der buffer. This method is used to set the raw subject field prior to signing.
int wc_GetSubjectRaw(byte ** subjectRaw, Cert * cert)
This function gets the raw subject from the certificate structure.
int wc_SetAltNames(Cert * cert, const char * file)
This function sets the alternate names for a certificate to the alternate names in the provided pem file. This is useful in the case that one wishes to secure multiple domains with the same certificate. This method is used to set fields prior to signing.
int wc_SetIssuerBuffer(Cert * cert, const byte * der, int derSz)
This function sets the issuer for a certificate from the issuer in the provided der buffer. It also changes the certificate’s self-signed attribute to false. This method is used to set fields prior to signing.
int wc_SetIssuerRaw(Cert * cert, const byte * der, int derSz)
This function sets the raw issuer for a certificate from the issuer in the provided der buffer. This method is used to set the raw issuer field prior to signing.
int wc_SetSubjectBuffer(Cert * cert, const byte * der, int derSz)
This function sets the subject for a certificate from the subject in the provided der buffer. This method is used to set fields prior to signing.
int wc_SetAltNamesBuffer(Cert * cert, const byte * der, int derSz)
This function sets the alternate names for a certificate from the alternate names in the provided der buffer. This is useful in the case that one wishes to secure multiple domains with the same certificate. This method is used to set fields prior to signing.
int wc_SetDatesBuffer(Cert * cert, const byte * der, int derSz)
This function sets the dates for a certificate from the date range in the provided der buffer. This method is used to set fields prior to signing.
int wc_SetAuthKeyIdFromPublicKey(Cert * cert, RsaKey * rsakey, ecc_key * eckey)
Set AKID from either an RSA or ECC public key. note: Only set one of rsakey or eckey, not both.
int wc_SetAuthKeyIdFromCert(Cert * cert, const byte * der, int derSz)
Set AKID from from DER encoded certificate.
int wc_SetAuthKeyId(Cert * cert, const char * file)
Set AKID from certificate file in PEM format.
int wc_SetSubjectKeyIdFromPublicKey(Cert * cert, RsaKey * rsakey, ecc_key * eckey)
Set SKID from RSA or ECC public key.
int wc_SetSubjectKeyId(Cert * cert, const char * file)
Set SKID from public key file in PEM format. Both arguments are required.
int wc_PemPubKeyToDer(const char * fileName, unsigned char * derBuf, int derSz)
Loads a PEM key from a file and converts to a DER encoded buffer.
int wc_PubKeyPemToDer(const unsigned char * pem, int pemSz, unsigned char * buff, int buffSz)
Convert a PEM encoded public key to DER. Returns the number of bytes written to the buffer or a negative value for an error.
int wc_PemCertToDer(const char * fileName, unsigned char * derBuf, int derSz)
This function converts a pem certificate to a der certificate, and places the resulting certificate in the derBuf buffer provided.
int wc_DerToPem(const byte * der, word32 derSz, byte * output, word32 outputSz, int type)
This function converts a der formatted input certificate, contained in the der buffer, into a pem formatted output certificate, contained in the output buffer. It should be noted that this is not an in place conversion, and a separate buffer must be utilized to store the pem formatted output.
int wc_DerToPemEx(const byte * der, word32 derSz, byte * output, word32 outputSz, byte * cipherIno, int type)
This function converts a der formatted input certificate, contained in the der buffer, into a pem formatted output certificate, contained in the output buffer. It should be noted that this is not an in place conversion, and a separate buffer must be utilized to store the pem formatted output. Allows setting cipher info.
int wc_EccPrivateKeyDecode(const byte * input, word32 * inOutIdx, ecc_key * key, word32 inSz)
This function reads in an ECC private key from the input buffer, input, parses the private key, and uses it to generate an ecc_key object, which it stores in key.
int wc_EccKeyToDer(ecc_key * key, byte * output, word32 inLen)
This function writes a private ECC key to der format.
int wc_EccPublicKeyDecode(const byte * input, word32 * inOutIdx, ecc_key * key, word32 inSz)
Decodes an ECC public key from an input buffer. It will parse an ASN sequence to retrieve the ECC key.
int wc_EccPublicKeyToDer(ecc_key * key, byte * output, word32 inLen, int with_AlgCurve)
This function converts the ECC public key to DER format. It returns the size of buffer used. The public ECC key in DER format is stored in output buffer. The with_AlgCurve flag will include a header that has the Algorithm and Curve information.
int wc_EccPublicKeyToDer_ex(ecc_key * key, byte * output, word32 inLen, int with_AlgCurve, int comp)
This function converts the ECC public key to DER format. It returns the size of buffer used. The public ECC key in DER format is stored in output buffer. The with_AlgCurve flag will include a header that has the Algorithm and Curve information. The comp parameter determines if the public key will be exported as compressed.
word32 wc_EncodeSignature(byte * out, const byte * digest, word32 digSz, int hashOID)
This function encodes a digital signature into the output buffer, and returns the size of the encoded signature created.
int wc_GetCTC_HashOID(int type)
This function returns the hash OID that corresponds to a hashing type. For example, when given the type: SHA512, this function returns the identifier corresponding to a SHA512 hash, SHA512h.
void wc_SetCert_Free(Cert * cert)
This function cleans up memory and resources used by the certificate structure's decoded cert cache. When WOLFSSL_CERT_GEN_CACHE is defined the decoded cert structure is cached in the certificate structure. This allows subsequent calls to certificate set functions to avoid parsing the decoded cert on each call.
int wc_GetPkcs8TraditionalOffset(byte * input, word32 * inOutIdx, word32 sz)
This function finds the beginning of the traditional private key inside a PKCS#8 unencrypted buffer.
int wc_CreatePKCS8Key(byte * out, word32 * outSz, byte * key, word32 keySz, int algoID, const byte * curveOID, word32 oidSz)
This function takes in a DER private key and converts it to PKCS#8 format. Also used in creating PKCS#12 shrouded key bags. See RFC 5208.
int wc_EncryptPKCS8Key(byte * key, word32 keySz, byte * out, word32 * outSz, const char * password, int passwordSz, int vPKCS, int pbeOid, int encAlgId, byte * salt, word32 saltSz, int itt, WC_RNG * rng, void * heap)
This function takes in an unencrypted PKCS#8 DER key (e.g. one created by wc_CreatePKCS8Key) and converts it to PKCS#8 encrypted format. The resulting encrypted key can be decrypted using wc_DecryptPKCS8Key. See RFC 5208.
int wc_DecryptPKCS8Key(byte * input, word32 sz, const char * password, int passwordSz)
This function takes an encrypted PKCS#8 DER key and decrypts it to PKCS#8 unencrypted DER. Undoes the encryption done by wc_EncryptPKCS8Key. See RFC5208. The input buffer is overwritten with the decrypted data.
int wc_CreateEncryptedPKCS8Key(byte * key, word32 keySz, byte * out, word32 * outSz, const char * password, int passwordSz, int vPKCS, int pbeOid, int encAlgId, byte * salt, word32 saltSz, int itt, WC_RNG * rng, void * heap)
This function takes a traditional, DER key, converts it to PKCS#8 format, and encrypts it. It uses wc_CreatePKCS8Key and wc_EncryptPKCS8Key to do this.
void wc_InitDecodedCert(struct DecodedCert * cert, const byte * source, word32 inSz, void * heap)
This function initializes the DecodedCert pointed to by the "cert" parameter. It saves the "source" pointer to a DER-encoded certificate of length "inSz." This certificate can be parsed by a subsequent call to wc_ParseCert.
int wc_ParseCert(DecodedCert * cert, int type, int verify, void * cm)
This function parses the DER-encoded certificate saved in the DecodedCert object and populates the fields of that object. The DecodedCert must have been initialized with a prior call to wc_InitDecodedCert. This function takes an optional pointer to a CertificateManager object, which is used to populate the certificate authority information of the DecodedCert, if the CA is found in the CertificateManager.
void wc_FreeDecodedCert(struct DecodedCert * cert)
This function frees a DecodedCert that was previously initialized with wc_InitDecodedCert.
int wc_SetTimeCb(wc_time_cb f)
This function registers a time callback that will be used anytime wolfSSL needs to get the current time. The prototype of the callback should be the same as the "time" function from the C standard library.
time_t wc_Time(time_t * t)
This function gets the current time. By default, it uses the XTIME macro, which varies between platforms. The user can use a function of their choosing instead via the wc_SetTimeCb function.
int wc_SetCustomExtension(Cert * cert, int critical, const char * oid, const byte * der, word32 derSz)
This function injects a custom extension in to an X.509 certificate.
WOLFSSL_ASN_API int wc_SetUnknownExtCallback(DecodedCert * cert, wc_UnknownExtCallback cb)
This function registers a callback that will be used anytime wolfSSL encounters an unknown X.509 extension in a certificate while parsing a certificate. The prototype of the callback should be:

Functions Documentation

function wc_InitCert

int wc_InitCert(
    Cert * 
)

This function initializes a default cert, with the default options: version = 3 (0x2), serial = 0, sigType = SHA_WITH_RSA, issuer = blank, daysValid = 500, selfSigned = 1 (true) use subject as issuer, subject = blank.

Parameters:

  • cert pointer to an uninitialized cert structure to initialize

See:

Return: none No returns.

Example

Cert myCert;
wc_InitCert(&myCert);

function wc_MakeCert

int wc_MakeCert(
    Cert * cert,
    byte * derBuffer,
    word32 derSz,
    RsaKey * rsaKey,
    ecc_key * eccKey,
    WC_RNG * rng
)

Used to make CA signed certs. Called after the subject information has been entered. This function makes an x509 Certificate v3 RSA or ECC from a cert input. It then writes this cert to derBuffer. It takes in either an rsaKey or an eccKey to generate the certificate. The certificate must be initialized with wc_InitCert before this method is called.

Parameters:

  • cert pointer to an initialized cert structure
  • derBuffer pointer to the buffer in which to hold the generated cert
  • derSz size of the buffer in which to store the cert
  • rsaKey pointer to an RsaKey structure containing the rsa key used to generate the certificate
  • eccKey pointer to an EccKey structure containing the ecc key used to generate the certificate
  • rng pointer to the random number generator used to make the cert

See:

Return:

  • Success On successfully making an x509 certificate from the specified input cert, returns the size of the cert generated.
  • MEMORY_E Returned if there is an error allocating memory with XMALLOC
  • BUFFER_E Returned if the provided derBuffer is too small to store the generated certificate
  • Others Additional error messages may be returned if the cert generation is not successful.

Example

Cert myCert;
wc_InitCert(&myCert);
WC_RNG rng;
//initialize rng;
RsaKey key;
//initialize key;
byte * derCert = malloc(FOURK_BUF);
word32 certSz;
certSz = wc_MakeCert(&myCert, derCert, FOURK_BUF, &key, NULL, &rng);

function wc_MakeCertReq

int wc_MakeCertReq(
    Cert * cert,
    byte * derBuffer,
    word32 derSz,
    RsaKey * rsaKey,
    ecc_key * eccKey
)

This function makes a certificate signing request using the input certificate and writes the output to derBuffer. It takes in either an rsaKey or an eccKey to generate the certificate request. wc_SignCert() will need to be called after this function to sign the certificate request. Please see the wolfCrypt test application (./wolfcrypt/test/test.c) for an example usage of this function.

Parameters:

  • cert pointer to an initialized cert structure
  • derBuffer pointer to the buffer in which to hold the generated certificate request
  • derSz size of the buffer in which to store the certificate request
  • rsaKey pointer to an RsaKey structure containing the rsa key used to generate the certificate request
  • eccKey pointer to an EccKey structure containing the ecc key used to generate the certificate request

See:

Return:

  • Success On successfully making an X.509 certificate request from the specified input cert, returns the size of the certificate request generated.
  • MEMORY_E Returned if there is an error allocating memory with XMALLOC
  • BUFFER_E Returned if the provided derBuffer is too small to store the generated certificate
  • Other Additional error messages may be returned if the certificate request generation is not successful.

Example

Cert myCert;
// initialize myCert
EccKey key;
//initialize key;
byte* derCert = (byte*)malloc(FOURK_BUF);

word32 certSz;
certSz = wc_MakeCertReq(&myCert, derCert, FOURK_BUF, NULL, &key);

function wc_SignCert

int wc_SignCert(
    int requestSz,
    int sigType,
    byte * derBuffer,
    word32 derSz,
    RsaKey * rsaKey,
    ecc_key * eccKey,
    WC_RNG * rng
)

This function signs buffer and adds the signature to the end of buffer. It takes in a signature type. Must be called after wc_MakeCert() or wc_MakeCertReq() if creating a CA signed cert.

Parameters:

  • requestSz the size of the certificate body we’re requesting to have signed
  • sType Type of signature to create. Valid options are: CTC_MD5wRSA, CTC_SHAwRSA, CTC_SHAwECDSA, CTC_SHA256wECDSA, andCTC_SHA256wRSA
  • buffer pointer to the buffer containing the certificate to be signed. On success: will hold the newly signed certificate
  • buffSz the (total) size of the buffer in which to store the newly signed certificate
  • rsaKey pointer to an RsaKey structure containing the rsa key to used to sign the certificate
  • eccKey pointer to an EccKey structure containing the ecc key to used to sign the certificate
  • rng pointer to the random number generator used to sign the certificate

See:

Return:

  • Success On successfully signing the certificate, returns the new size of the cert (including signature).
  • MEMORY_E Returned if there is an error allocating memory with XMALLOC
  • BUFFER_E Returned if the provided buffer is too small to store the generated certificate
  • Other Additional error messages may be returned if the cert generation is not successful.

Example

Cert myCert;
byte* derCert = (byte*)malloc(FOURK_BUF);
// initialize myCert, derCert
RsaKey key;
// initialize key;
WC_RNG rng;
// initialize rng

word32 certSz;
certSz = wc_SignCert(myCert.bodySz, myCert.sigType,derCert,FOURK_BUF,
&key, NULL,
&rng);

function wc_MakeSelfCert

int wc_MakeSelfCert(
    Cert * cert,
    byte * derBuffer,
    word32 derSz,
    RsaKey * key,
    WC_RNG * rng
)

This function is a combination of the previous two functions, wc_MakeCert and wc_SignCert for self signing (the previous functions may be used for CA requests). It makes a certificate, and then signs it, generating a self-signed certificate.

Parameters:

  • cert pointer to the cert to make and sign
  • buffer pointer to the buffer in which to hold the signed certificate
  • buffSz size of the buffer in which to store the signed certificate
  • key pointer to an RsaKey structure containing the rsa key to used to sign the certificate
  • rng pointer to the random number generator used to generate and sign the certificate

See:

Return:

  • Success On successfully signing the certificate, returns the new size of the cert.
  • MEMORY_E Returned if there is an error allocating memory with XMALLOC
  • BUFFER_E Returned if the provided buffer is too small to store the generated certificate
  • Other Additional error messages may be returned if the cert generation is not successful.

Example

Cert myCert;
byte* derCert = (byte*)malloc(FOURK_BUF);
// initialize myCert, derCert
RsaKey key;
// initialize key;
WC_RNG rng;
// initialize rng

word32 certSz;
certSz = wc_MakeSelfCert(&myCert, derCert, FOURK_BUF, &key, NULL, &rng);

function wc_SetIssuer

int wc_SetIssuer(
    Cert * cert,
    const char * issuerFile
)

This function sets the issuer for a certificate to the issuer in the provided pem issuerFile. It also changes the certificate’s self-signed attribute to false. The issuer specified in issuerFile is verified prior to setting the cert issuer. This method is used to set fields prior to signing.

Parameters:

  • cert pointer to the cert for which to set the issuer
  • issuerFile path of the file containing the pem formatted certificate

See:

Return:

  • 0 Returned on successfully setting the issuer for the certificate
  • MEMORY_E Returned if there is an error allocating memory with XMALLOC
  • ASN_PARSE_E Returned if there is an error parsing the cert header file
  • ASN_OBJECT_ID_E Returned if there is an error parsing the encryption type from the cert
  • ASN_EXPECT_0_E Returned if there is a formatting error in the encryption specification of the cert file
  • ASN_BEFORE_DATE_E Returned if the date is before the certificate start date
  • ASN_AFTER_DATE_E Returned if the date is after the certificate expiration date
  • ASN_BITSTR_E Returned if there is an error parsing a bit string from the certificate
  • ECC_CURVE_OID_E Returned if there is an error parsing the ECC key from the certificate
  • ASN_UNKNOWN_OID_E Returned if the certificate is using an unknown key object id
  • ASN_VERSION_E Returned if the ALLOW_V1_EXTENSIONS option is not defined and the certificate is a V1 or V2 certificate
  • BAD_FUNC_ARG Returned if there is an error processing the certificate extension
  • ASN_CRIT_EXT_E Returned if an unfamiliar critical extension is encountered in processing the certificate
  • ASN_SIG_OID_E Returned if the signature encryption type is not the same as the encryption type of the certificate in the provided file
  • ASN_SIG_CONFIRM_E Returned if confirming the certification signature fails
  • ASN_NAME_INVALID_E Returned if the certificate’s name is not permitted by the CA name constraints
  • ASN_NO_SIGNER_E Returned if there is no CA signer to verify the certificate’s authenticity

Example

Cert myCert;
// initialize myCert
if(wc_SetIssuer(&myCert, ”./path/to/ca-cert.pem”) != 0) {
    // error setting issuer
}

function wc_SetSubject

int wc_SetSubject(
    Cert * cert,
    const char * subjectFile
)

This function sets the subject for a certificate to the subject in the provided pem subjectFile. This method is used to set fields prior to signing.

Parameters:

  • cert pointer to the cert for which to set the issuer
  • subjectFile path of the file containing the pem formatted certificate

See:

Return:

  • 0 Returned on successfully setting the issuer for the certificate
  • MEMORY_E Returned if there is an error allocating memory with XMALLOC
  • ASN_PARSE_E Returned if there is an error parsing the cert header file
  • ASN_OBJECT_ID_E Returned if there is an error parsing the encryption type from the cert
  • ASN_EXPECT_0_E Returned if there is a formatting error in the encryption specification of the cert file
  • ASN_BEFORE_DATE_E Returned if the date is before the certificate start date
  • ASN_AFTER_DATE_E Returned if the date is after the certificate expiration date
  • ASN_BITSTR_E Returned if there is an error parsing a bit string from the certificate
  • ECC_CURVE_OID_E Returned if there is an error parsing the ECC key from the certificate
  • ASN_UNKNOWN_OID_E Returned if the certificate is using an unknown key object id
  • ASN_VERSION_E Returned if the ALLOW_V1_EXTENSIONS option is not defined and the certificate is a V1 or V2 certificate
  • BAD_FUNC_ARG Returned if there is an error processing the certificate extension
  • ASN_CRIT_EXT_E Returned if an unfamiliar critical extension is encountered in processing the certificate
  • ASN_SIG_OID_E Returned if the signature encryption type is not the same as the encryption type of the certificate in the provided file
  • ASN_SIG_CONFIRM_E Returned if confirming the certification signature fails
  • ASN_NAME_INVALID_E Returned if the certificate’s name is not permitted by the CA name constraints
  • ASN_NO_SIGNER_E Returned if there is no CA signer to verify the certificate’s authenticity

Example

Cert myCert;
// initialize myCert
if(wc_SetSubject(&myCert, ”./path/to/ca-cert.pem”) != 0) {
    // error setting subject
}

function wc_SetSubjectRaw

int wc_SetSubjectRaw(
    Cert * cert,
    const byte * der,
    int derSz
)

This function sets the raw subject for a certificate from the subject in the provided der buffer. This method is used to set the raw subject field prior to signing.

Parameters:

  • cert pointer to the cert for which to set the raw subject
  • der pointer to the buffer containing the der formatted certificate from which to grab the subject
  • derSz size of the buffer containing the der formatted certificate from which to grab the subject

See:

Return:

  • 0 Returned on successfully setting the subject for the certificate
  • MEMORY_E Returned if there is an error allocating memory with XMALLOC
  • ASN_PARSE_E Returned if there is an error parsing the cert header file
  • ASN_OBJECT_ID_E Returned if there is an error parsing the encryption type from the cert
  • ASN_EXPECT_0_E Returned if there is a formatting error in the encryption specification of the cert file
  • ASN_BEFORE_DATE_E Returned if the date is before the certificate start date
  • ASN_AFTER_DATE_E Returned if the date is after the certificate expiration date
  • ASN_BITSTR_E Returned if there is an error parsing a bit string from the certificate
  • ECC_CURVE_OID_E Returned if there is an error parsing the ECC key from the certificate
  • ASN_UNKNOWN_OID_E Returned if the certificate is using an unknown key object id
  • ASN_VERSION_E Returned if the ALLOW_V1_EXTENSIONS option is not defined and the certificate is a V1 or V2 certificate
  • BAD_FUNC_ARG Returned if there is an error processing the certificate extension
  • ASN_CRIT_EXT_E Returned if an unfamiliar critical extension is encountered in processing the certificate
  • ASN_SIG_OID_E Returned if the signature encryption type is not the same as the encryption type of the certificate in the provided file
  • ASN_SIG_CONFIRM_E Returned if confirming the certification signature fails
  • ASN_NAME_INVALID_E Returned if the certificate’s name is not permitted by the CA name constraints
  • ASN_NO_SIGNER_E Returned if there is no CA signer to verify the certificate’s authenticity

Example

Cert myCert;
// initialize myCert
byte* der;
der = (byte*)malloc(FOURK_BUF);
// initialize der
if(wc_SetSubjectRaw(&myCert, der, FOURK_BUF) != 0) {
    // error setting subject
}

function wc_GetSubjectRaw

int wc_GetSubjectRaw(
    byte ** subjectRaw,
    Cert * cert
)

This function gets the raw subject from the certificate structure.

Parameters:

  • subjectRaw pointer-pointer to the raw subject upon successful return
  • cert pointer to the cert from which to get the raw subject

See:

Return:

  • 0 Returned on successfully getting the subject from the certificate
  • BAD_FUNC_ARG Returned if there is an error processing the certificate extension

Example

Cert myCert;
byte *subjRaw;
// initialize myCert

if(wc_GetSubjectRaw(&subjRaw, &myCert) != 0) {
    // error setting subject
}

function wc_SetAltNames

int wc_SetAltNames(
    Cert * cert,
    const char * file
)

This function sets the alternate names for a certificate to the alternate names in the provided pem file. This is useful in the case that one wishes to secure multiple domains with the same certificate. This method is used to set fields prior to signing.

Parameters:

  • cert pointer to the cert for which to set the alt names
  • file path of the file containing the pem formatted certificate

See:

Return:

  • 0 Returned on successfully setting the alt names for the certificate
  • MEMORY_E Returned if there is an error allocating memory with XMALLOC
  • ASN_PARSE_E Returned if there is an error parsing the cert header file
  • ASN_OBJECT_ID_E Returned if there is an error parsing the encryption type from the cert
  • ASN_EXPECT_0_E Returned if there is a formatting error in the encryption specification of the cert file
  • ASN_BEFORE_DATE_E Returned if the date is before the certificate start date
  • ASN_AFTER_DATE_E Returned if the date is after the certificate expiration date
  • ASN_BITSTR_E Returned if there is an error parsing a bit string from the certificate
  • ECC_CURVE_OID_E Returned if there is an error parsing the ECC key from the certificate
  • ASN_UNKNOWN_OID_E Returned if the certificate is using an unknown key object id
  • ASN_VERSION_E Returned if the ALLOW_V1_EXTENSIONS option is not defined and the certificate is a V1 or V2 certificate
  • BAD_FUNC_ARG Returned if there is an error processing the certificate extension
  • ASN_CRIT_EXT_E Returned if an unfamiliar critical extension is encountered in processing the certificate
  • ASN_SIG_OID_E Returned if the signature encryption type is not the same as the encryption type of the certificate in the provided file
  • ASN_SIG_CONFIRM_E Returned if confirming the certification signature fails
  • ASN_NAME_INVALID_E Returned if the certificate’s name is not permitted by the CA name constraints
  • ASN_NO_SIGNER_E Returned if there is no CA signer to verify the certificate’s authenticity

Example

Cert myCert;
// initialize myCert
if(wc_SetSubject(&myCert, ”./path/to/ca-cert.pem”) != 0) {
    // error setting alt names
}

function wc_SetIssuerBuffer

int wc_SetIssuerBuffer(
    Cert * cert,
    const byte * der,
    int derSz
)

This function sets the issuer for a certificate from the issuer in the provided der buffer. It also changes the certificate’s self-signed attribute to false. This method is used to set fields prior to signing.

Parameters:

  • cert pointer to the cert for which to set the issuer
  • der pointer to the buffer containing the der formatted certificate from which to grab the issuer
  • derSz size of the buffer containing the der formatted certificate from which to grab the issuer

See:

Return:

  • 0 Returned on successfully setting the issuer for the certificate
  • MEMORY_E Returned if there is an error allocating memory with XMALLOC
  • ASN_PARSE_E Returned if there is an error parsing the cert header file
  • ASN_OBJECT_ID_E Returned if there is an error parsing the encryption type from the cert
  • ASN_EXPECT_0_E Returned if there is a formatting error in the encryption specification of the cert file
  • ASN_BEFORE_DATE_E Returned if the date is before the certificate start date
  • ASN_AFTER_DATE_E Returned if the date is after the certificate expiration date
  • ASN_BITSTR_E Returned if there is an error parsing a bit string from the certificate
  • ECC_CURVE_OID_E Returned if there is an error parsing the ECC key from the certificate
  • ASN_UNKNOWN_OID_E Returned if the certificate is using an unknown key object id
  • ASN_VERSION_E Returned if the ALLOW_V1_EXTENSIONS option is not defined and the certificate is a V1 or V2 certificate
  • BAD_FUNC_ARG Returned if there is an error processing the certificate extension
  • ASN_CRIT_EXT_E Returned if an unfamiliar critical extension is encountered in processing the certificate
  • ASN_SIG_OID_E Returned if the signature encryption type is not the same as the encryption type of the certificate in the provided file
  • ASN_SIG_CONFIRM_E Returned if confirming the certification signature fails
  • ASN_NAME_INVALID_E Returned if the certificate’s name is not permitted by the CA name constraints
  • ASN_NO_SIGNER_E Returned if there is no CA signer to verify the certificate’s authenticity

Example

Cert myCert;
// initialize myCert
byte* der;
der = (byte*)malloc(FOURK_BUF);
// initialize der
if(wc_SetIssuerBuffer(&myCert, der, FOURK_BUF) != 0) {
    // error setting issuer
}

function wc_SetIssuerRaw

int wc_SetIssuerRaw(
    Cert * cert,
    const byte * der,
    int derSz
)

This function sets the raw issuer for a certificate from the issuer in the provided der buffer. This method is used to set the raw issuer field prior to signing.

Parameters:

  • cert pointer to the cert for which to set the raw issuer
  • der pointer to the buffer containing the der formatted certificate from which to grab the subject
  • derSz size of the buffer containing the der formatted certificate from which to grab the subject

See:

Return:

  • 0 Returned on successfully setting the issuer for the certificate
  • MEMORY_E Returned if there is an error allocating memory with XMALLOC
  • ASN_PARSE_E Returned if there is an error parsing the cert header file
  • ASN_OBJECT_ID_E Returned if there is an error parsing the encryption type from the cert
  • ASN_EXPECT_0_E Returned if there is a formatting error in the encryption specification of the cert file
  • ASN_BEFORE_DATE_E Returned if the date is before the certificate start date
  • ASN_AFTER_DATE_E Returned if the date is after the certificate expiration date
  • ASN_BITSTR_E Returned if there is an error parsing a bit string from the certificate
  • ECC_CURVE_OID_E Returned if there is an error parsing the ECC key from the certificate
  • ASN_UNKNOWN_OID_E Returned if the certificate is using an unknown key object id
  • ASN_VERSION_E Returned if the ALLOW_V1_EXTENSIONS option is not defined and the certificate is a V1 or V2 certificate
  • BAD_FUNC_ARG Returned if there is an error processing the certificate extension
  • ASN_CRIT_EXT_E Returned if an unfamiliar critical extension is encountered in processing the certificate
  • ASN_SIG_OID_E Returned if the signature encryption type is not the same as the encryption type of the certificate in the provided file
  • ASN_SIG_CONFIRM_E Returned if confirming the certification signature fails
  • ASN_NAME_INVALID_E Returned if the certificate’s name is not permitted by the CA name constraints
  • ASN_NO_SIGNER_E Returned if there is no CA signer to verify the certificate’s authenticity

Example

Cert myCert;
// initialize myCert
byte* der;
der = (byte*)malloc(FOURK_BUF);
// initialize der
if(wc_SetIssuerRaw(&myCert, der, FOURK_BUF) != 0) {
    // error setting subject
}

function wc_SetSubjectBuffer

int wc_SetSubjectBuffer(
    Cert * cert,
    const byte * der,
    int derSz
)

This function sets the subject for a certificate from the subject in the provided der buffer. This method is used to set fields prior to signing.

Parameters:

  • cert pointer to the cert for which to set the subject
  • der pointer to the buffer containing the der formatted certificate from which to grab the subject
  • derSz size of the buffer containing the der formatted certificate from which to grab the subject

See:

Return:

  • 0 Returned on successfully setting the subject for the certificate
  • MEMORY_E Returned if there is an error allocating memory with XMALLOC
  • ASN_PARSE_E Returned if there is an error parsing the cert header file
  • ASN_OBJECT_ID_E Returned if there is an error parsing the encryption type from the cert
  • ASN_EXPECT_0_E Returned if there is a formatting error in the encryption specification of the cert file
  • ASN_BEFORE_DATE_E Returned if the date is before the certificate start date
  • ASN_AFTER_DATE_E Returned if the date is after the certificate expiration date
  • ASN_BITSTR_E Returned if there is an error parsing a bit string from the certificate
  • ECC_CURVE_OID_E Returned if there is an error parsing the ECC key from the certificate
  • ASN_UNKNOWN_OID_E Returned if the certificate is using an unknown key object id
  • ASN_VERSION_E Returned if the ALLOW_V1_EXTENSIONS option is not defined and the certificate is a V1 or V2 certificate
  • BAD_FUNC_ARG Returned if there is an error processing the certificate extension
  • ASN_CRIT_EXT_E Returned if an unfamiliar critical extension is encountered in processing the certificate
  • ASN_SIG_OID_E Returned if the signature encryption type is not the same as the encryption type of the certificate in the provided file
  • ASN_SIG_CONFIRM_E Returned if confirming the certification signature fails
  • ASN_NAME_INVALID_E Returned if the certificate’s name is not permitted by the CA name constraints
  • ASN_NO_SIGNER_E Returned if there is no CA signer to verify the certificate’s authenticity

Example

Cert myCert;
// initialize myCert
byte* der;
der = (byte*)malloc(FOURK_BUF);
// initialize der
if(wc_SetSubjectBuffer(&myCert, der, FOURK_BUF) != 0) {
    // error setting subject
}

function wc_SetAltNamesBuffer

int wc_SetAltNamesBuffer(
    Cert * cert,
    const byte * der,
    int derSz
)

This function sets the alternate names for a certificate from the alternate names in the provided der buffer. This is useful in the case that one wishes to secure multiple domains with the same certificate. This method is used to set fields prior to signing.

Parameters:

  • cert pointer to the cert for which to set the alternate names
  • der pointer to the buffer containing the der formatted certificate from which to grab the alternate names
  • derSz size of the buffer containing the der formatted certificate from which to grab the alternate names

See:

Return:

  • 0 Returned on successfully setting the alternate names for the certificate
  • MEMORY_E Returned if there is an error allocating memory with XMALLOC
  • ASN_PARSE_E Returned if there is an error parsing the cert header file
  • ASN_OBJECT_ID_E Returned if there is an error parsing the encryption type from the cert
  • ASN_EXPECT_0_E Returned if there is a formatting error in the encryption specification of the cert file
  • ASN_BEFORE_DATE_E Returned if the date is before the certificate start date
  • ASN_AFTER_DATE_E Returned if the date is after the certificate expiration date
  • ASN_BITSTR_E Returned if there is an error parsing a bit string from the certificate
  • ECC_CURVE_OID_E Returned if there is an error parsing the ECC key from the certificate
  • ASN_UNKNOWN_OID_E Returned if the certificate is using an unknown key object id
  • ASN_VERSION_E Returned if the ALLOW_V1_EXTENSIONS option is not defined and the certificate is a V1 or V2 certificate
  • BAD_FUNC_ARG Returned if there is an error processing the certificate extension
  • ASN_CRIT_EXT_E Returned if an unfamiliar critical extension is encountered in processing the certificate
  • ASN_SIG_OID_E Returned if the signature encryption type is not the same as the encryption type of the certificate in the provided file
  • ASN_SIG_CONFIRM_E Returned if confirming the certification signature fails
  • ASN_NAME_INVALID_E Returned if the certificate’s name is not permitted by the CA name constraints
  • ASN_NO_SIGNER_E Returned if there is no CA signer to verify the certificate’s authenticity

Example

Cert myCert;
// initialize myCert
byte* der;
der = (byte*)malloc(FOURK_BUF);
// initialize der
if(wc_SetAltNamesBuffer(&myCert, der, FOURK_BUF) != 0) {
    // error setting subject
}

function wc_SetDatesBuffer

int wc_SetDatesBuffer(
    Cert * cert,
    const byte * der,
    int derSz
)

This function sets the dates for a certificate from the date range in the provided der buffer. This method is used to set fields prior to signing.

Parameters:

  • cert pointer to the cert for which to set the dates
  • der pointer to the buffer containing the der formatted certificate from which to grab the date range
  • derSz size of the buffer containing the der formatted certificate from which to grab the date range

See: wc_InitCert

Return:

  • 0 Returned on successfully setting the dates for the certificate
  • MEMORY_E Returned if there is an error allocating memory with XMALLOC
  • ASN_PARSE_E Returned if there is an error parsing the cert header file
  • ASN_OBJECT_ID_E Returned if there is an error parsing the encryption type from the cert
  • ASN_EXPECT_0_E Returned if there is a formatting error in the encryption specification of the cert file
  • ASN_BEFORE_DATE_E Returned if the date is before the certificate start date
  • ASN_AFTER_DATE_E Returned if the date is after the certificate expiration date
  • ASN_BITSTR_E Returned if there is an error parsing a bit string from the certificate
  • ECC_CURVE_OID_E Returned if there is an error parsing the ECC key from the certificate
  • ASN_UNKNOWN_OID_E Returned if the certificate is using an unknown key object id
  • ASN_VERSION_E Returned if the ALLOW_V1_EXTENSIONS option is not defined and the certificate is a V1 or V2 certificate
  • BAD_FUNC_ARG Returned if there is an error processing the certificate extension
  • ASN_CRIT_EXT_E Returned if an unfamiliar critical extension is encountered in processing the certificate
  • ASN_SIG_OID_E Returned if the signature encryption type is not the same as the encryption type of the certificate in the provided file
  • ASN_SIG_CONFIRM_E Returned if confirming the certification signature fails
  • ASN_NAME_INVALID_E Returned if the certificate’s name is not permitted by the CA name constraints
  • ASN_NO_SIGNER_E Returned if there is no CA signer to verify the certificate’s authenticity

Example

Cert myCert;
// initialize myCert
byte* der;
der = (byte*)malloc(FOURK_BUF);
// initialize der
if(wc_SetDatesBuffer(&myCert, der, FOURK_BUF) != 0) {
    // error setting subject
}

function wc_SetAuthKeyIdFromPublicKey

int wc_SetAuthKeyIdFromPublicKey(
    Cert * cert,
    RsaKey * rsakey,
    ecc_key * eckey
)

Set AKID from either an RSA or ECC public key. note: Only set one of rsakey or eckey, not both.

Parameters:

  • cert Pointer to the certificate to set the SKID.
  • rsakey Pointer to the RsaKey struct to read from.
  • eckey Pointer to the ecc_key to read from.

See:

Return:

  • 0 Success
  • BAD_FUNC_ARG Either cert is null or both rsakey and eckey are null.
  • MEMORY_E Error allocating memory.
  • PUBLIC_KEY_E Error writing to the key.

Example

Cert myCert;
RsaKey keypub;

wc_InitRsaKey(&keypub, 0);

if (wc_SetAuthKeyIdFromPublicKey(&myCert, &keypub, NULL) != 0)
{
    // Handle error
}

function wc_SetAuthKeyIdFromCert

int wc_SetAuthKeyIdFromCert(
    Cert * cert,
    const byte * der,
    int derSz
)

Set AKID from from DER encoded certificate.

Parameters:

  • cert The Cert struct to write to.
  • der The DER encoded certificate buffer.
  • derSz Size of der in bytes.

See:

Return:

  • 0 Success
  • BAD_FUNC_ARG Error if any argument is null or derSz is less than 0.
  • MEMORY_E Error if problem allocating memory.
  • ASN_NO_SKID No subject key ID found.

Example

Cert some_cert;
byte some_der[] = { // Initialize a DER buffer };
wc_InitCert(&some_cert);
if(wc_SetAuthKeyIdFromCert(&some_cert, some_der, sizeof(some_der) != 0)
{
    // Handle error
}

function wc_SetAuthKeyId

int wc_SetAuthKeyId(
    Cert * cert,
    const char * file
)

Set AKID from certificate file in PEM format.

Parameters:

  • cert Cert struct you want to set the AKID of.
  • file Buffer containing PEM cert file.

See:

Return:

  • 0 Success
  • BAD_FUNC_ARG Error if cert or file is null.
  • MEMORY_E Error if problem allocating memory.

Example

char* file_name = "/path/to/file";
cert some_cert;
wc_InitCert(&some_cert);

if(wc_SetAuthKeyId(&some_cert, file_name) != 0)
{
    // Handle Error
}

function wc_SetSubjectKeyIdFromPublicKey

int wc_SetSubjectKeyIdFromPublicKey(
    Cert * cert,
    RsaKey * rsakey,
    ecc_key * eckey
)

Set SKID from RSA or ECC public key.

Parameters:

  • cert Pointer to a Cert structure to be used.
  • rsakey Pointer to an RsaKey structure
  • eckey Pointer to an ecc_key structure

See: wc_SetSubjectKeyId

Return:

  • 0 Success
  • BAD_FUNC_ARG Returned if cert or rsakey and eckey is null.
  • MEMORY_E Returned if there is an error allocating memory.
  • PUBLIC_KEY_E Returned if there is an error getting the public key.

Example

Cert some_cert;
RsaKey some_key;
wc_InitCert(&some_cert);
wc_InitRsaKey(&some_key);

if(wc_SetSubjectKeyIdFromPublicKey(&some_cert,&some_key, NULL) != 0)
{
    // Handle Error
}

function wc_SetSubjectKeyId

int wc_SetSubjectKeyId(
    Cert * cert,
    const char * file
)

Set SKID from public key file in PEM format. Both arguments are required.

Parameters:

  • cert Cert structure to set the SKID of.
  • file Contains the PEM encoded file.

See: wc_SetSubjectKeyIdFromPublicKey

Return:

  • 0 Success
  • BAD_FUNC_ARG Returns if cert or file is null.
  • MEMORY_E Returns if there is a problem allocating memory for key.
  • PUBLIC_KEY_E Returns if there is an error decoding the public key.

Example

const char* file_name = "path/to/file";
Cert some_cert;
wc_InitCert(&some_cert);

if(wc_SetSubjectKeyId(&some_cert, file_name) != 0)
{
    // Handle Error
}

function wc_PemPubKeyToDer

int wc_PemPubKeyToDer(
    const char * fileName,
    unsigned char * derBuf,
    int derSz
)

Loads a PEM key from a file and converts to a DER encoded buffer.

Parameters:

  • fileName Name of the file to load.
  • derBuf Buffer for DER encoded key.
  • derSz Size of DER buffer.

See: wc_PubKeyPemToDer

Return:

  • 0 Success
  • <0 Error
  • SSL_BAD_FILE There is a problem with opening the file.
  • MEMORY_E There is an error allocating memory for the file buffer.
  • BUFFER_E derBuf is not large enough to hold the converted key.

Example

char* some_file = "filename";
unsigned char der[];

if(wc_PemPubKeyToDer(some_file, der, sizeof(der)) != 0)
{
    //Handle Error
}

function wc_PubKeyPemToDer

int wc_PubKeyPemToDer(
    const unsigned char * pem,
    int pemSz,
    unsigned char * buff,
    int buffSz
)

Convert a PEM encoded public key to DER. Returns the number of bytes written to the buffer or a negative value for an error.

Parameters:

  • pem PEM encoded key
  • pemSz Size of pem
  • buff Pointer to buffer for output.
  • buffSz Size of buffer.

See: wc_PemPubKeyToDer

Return:

  • 0 Success, number of bytes written.

  • BAD_FUNC_ARG Returns if pem, buff, or buffSz are null
  • <0 An error occurred in the function.

Example

byte some_pem[] = { Initialize with PEM key }
unsigned char out_buffer[1024]; // Ensure buffer is large enough to fit DER

if(wc_PubKeyPemToDer(some_pem, sizeof(some_pem), out_buffer,
sizeof(out_buffer)) < 0)
{
    // Handle error
}

function wc_PemCertToDer

int wc_PemCertToDer(
    const char * fileName,
    unsigned char * derBuf,
    int derSz
)

This function converts a pem certificate to a der certificate, and places the resulting certificate in the derBuf buffer provided.

Parameters:

  • fileName path to the file containing a pem certificate to convert to a der certificate
  • derBuf pointer to a char buffer in which to store the converted certificate
  • derSz size of the char buffer in which to store the converted certificate

See: none

Return:

  • Success On success returns the size of the derBuf generated
  • BUFFER_E Returned if the size of derBuf is too small to hold the certificate generated
  • MEMORY_E Returned if the call to XMALLOC fails

Example

char * file = “./certs/client-cert.pem”;
int derSz;
byte* der = (byte*)XMALLOC((8*1024), NULL, DYNAMIC_TYPE_CERT);

derSz = wc_PemCertToDer(file, der, (8*1024));
if (derSz <= 0) {
    //PemCertToDer error
}

function wc_DerToPem

int wc_DerToPem(
    const byte * der,
    word32 derSz,
    byte * output,
    word32 outputSz,
    int type
)

This function converts a der formatted input certificate, contained in the der buffer, into a pem formatted output certificate, contained in the output buffer. It should be noted that this is not an in place conversion, and a separate buffer must be utilized to store the pem formatted output.

Parameters:

  • der pointer to the buffer of the certificate to convert
  • derSz size of the the certificate to convert
  • output pointer to the buffer in which to store the pem formatted certificate
  • outSz size of the buffer in which to store the pem formatted certificate
  • type the type of certificate to generate. Valid types are: CERT_TYPE, PRIVATEKEY_TYPE, ECC_PRIVATEKEY_TYPE, and CERTREQ_TYPE.

See: wc_PemCertToDer

Return:

  • Success On successfully making a pem certificate from the input der cert, returns the size of the pem cert generated.
  • BAD_FUNC_ARG Returned if there is an error parsing the der file and storing it as a pem file
  • MEMORY_E Returned if there is an error allocating memory with XMALLOC
  • ASN_INPUT_E Returned in the case of a base64 encoding error
  • BUFFER_E May be returned if the output buffer is too small to store the pem formatted certificate

Example

byte* der;
// initialize der with certificate
byte* pemFormatted[FOURK_BUF];

word32 pemSz;
pemSz = wc_DerToPem(der, derSz,pemFormatted,FOURK_BUF, CERT_TYPE);

function wc_DerToPemEx

int wc_DerToPemEx(
    const byte * der,
    word32 derSz,
    byte * output,
    word32 outputSz,
    byte * cipherIno,
    int type
)

This function converts a der formatted input certificate, contained in the der buffer, into a pem formatted output certificate, contained in the output buffer. It should be noted that this is not an in place conversion, and a separate buffer must be utilized to store the pem formatted output. Allows setting cipher info.

Parameters:

  • der pointer to the buffer of the certificate to convert
  • derSz size of the the certificate to convert
  • output pointer to the buffer in which to store the pem formatted certificate
  • outSz size of the buffer in which to store the pem formatted certificate
  • cipher_inf Additional cipher information.
  • type the type of certificate to generate. Valid types are: CERT_TYPE, PRIVATEKEY_TYPE, ECC_PRIVATEKEY_TYPE, and CERTREQ_TYPE.

See: wc_PemCertToDer

Return:

  • Success On successfully making a pem certificate from the input der cert, returns the size of the pem cert generated.
  • BAD_FUNC_ARG Returned if there is an error parsing the der file and storing it as a pem file
  • MEMORY_E Returned if there is an error allocating memory with XMALLOC
  • ASN_INPUT_E Returned in the case of a base64 encoding error
  • BUFFER_E May be returned if the output buffer is too small to store the pem formatted certificate

Example

byte* der;
// initialize der with certificate
byte* pemFormatted[FOURK_BUF];

word32 pemSz;
byte* cipher_info[] { Additional cipher info. }
pemSz = wc_DerToPemEx(der, derSz,pemFormatted,FOURK_BUF, ,CERT_TYPE);

function wc_EccPrivateKeyDecode

int wc_EccPrivateKeyDecode(
    const byte * input,
    word32 * inOutIdx,
    ecc_key * key,
    word32 inSz
)

This function reads in an ECC private key from the input buffer, input, parses the private key, and uses it to generate an ecc_key object, which it stores in key.

Parameters:

  • input pointer to the buffer containing the input private key
  • inOutIdx pointer to a word32 object containing the index in the buffer at which to start
  • key pointer to an initialized ecc object, on which to store the decoded private key
  • inSz size of the input buffer containing the private key

See: wc_RSA_PrivateKeyDecode

Return:

  • 0 On successfully decoding the private key and storing the result in the ecc_key struct
  • ASN_PARSE_E: Returned if there is an error parsing the der file and storing it as a pem file
  • MEMORY_E Returned if there is an error allocating memory with XMALLOC
  • BUFFER_E Returned if the certificate to convert is large than the specified max certificate size
  • ASN_OBJECT_ID_E Returned if the certificate encoding has an invalid object id
  • ECC_CURVE_OID_E Returned if the ECC curve of the provided key is not supported
  • ECC_BAD_ARG_E Returned if there is an error in the ECC key format
  • NOT_COMPILED_IN Returned if the private key is compressed, and no compression key is provided
  • MP_MEM Returned if there is an error in the math library used while parsing the private key
  • MP_VAL Returned if there is an error in the math library used while parsing the private key
  • MP_RANGE Returned if there is an error in the math library used while parsing the private key

Example

int ret, idx=0;
ecc_key key; // to store key in

byte* tmp; // tmp buffer to read key from
tmp = (byte*) malloc(FOURK_BUF);

int inSz;
inSz = fread(tmp, 1, FOURK_BUF, privateKeyFile);
// read key into tmp buffer

wc_ecc_init(&key); // initialize key
ret = wc_EccPrivateKeyDecode(tmp, &idx, &key, (word32)inSz);
if(ret < 0) {
    // error decoding ecc key
}

function wc_EccKeyToDer

int wc_EccKeyToDer(
    ecc_key * key,
    byte * output,
    word32 inLen
)

This function writes a private ECC key to der format.

Parameters:

  • key pointer to the buffer containing the input ecc key
  • output pointer to a buffer in which to store the der formatted key
  • inLen the length of the buffer in which to store the der formatted key

See: wc_RsaKeyToDer

Return:

  • Success On successfully writing the ECC key to der format, returns the length written to the buffer
  • BAD_FUNC_ARG Returned if key or output is null, or inLen equals zero
  • MEMORY_E Returned if there is an error allocating memory with XMALLOC
  • BUFFER_E Returned if the converted certificate is too large to store in the output buffer
  • ASN_UNKNOWN_OID_E Returned if the ECC key used is of an unknown type
  • MP_MEM Returned if there is an error in the math library used while parsing the private key
  • MP_VAL Returned if there is an error in the math library used while parsing the private key
  • MP_RANGE Returned if there is an error in the math library used while parsing the private key

Example

int derSz;
ecc_key key;
// initialize and make key
byte der[FOURK_BUF];
// store der formatted key here

derSz = wc_EccKeyToDer(&key, der, FOURK_BUF);
if(derSz < 0) {
    // error converting ecc key to der buffer
}

function wc_EccPublicKeyDecode

int wc_EccPublicKeyDecode(
    const byte * input,
    word32 * inOutIdx,
    ecc_key * key,
    word32 inSz
)

Decodes an ECC public key from an input buffer. It will parse an ASN sequence to retrieve the ECC key.

Parameters:

  • input Buffer containing DER encoded key to decode.
  • inOutIdx Index to start reading input buffer from. On output, index is set to last position parsed of input buffer.
  • key Pointer to ecc_key struct to store the public key.
  • inSz Size of the input buffer.

See: wc_ecc_import_x963

Return:

  • 0 Success
  • BAD_FUNC_ARG Returns if any arguments are null.
  • ASN_PARSE_E Returns if there is an error parsing
  • ASN_ECC_KEY_E Returns if there is an error importing the key. See wc_ecc_import_x963 for possible reasons.

Example

int ret;
word32 idx = 0;
byte buff[] = { // initialize with key };
ecc_key pubKey;
wc_ecc_init(&pubKey);
if ( wc_EccPublicKeyDecode(buff, &idx, &pubKey, sizeof(buff)) != 0) {
        // error decoding key
}

function wc_EccPublicKeyToDer

int wc_EccPublicKeyToDer(
    ecc_key * key,
    byte * output,
    word32 inLen,
    int with_AlgCurve
)

This function converts the ECC public key to DER format. It returns the size of buffer used. The public ECC key in DER format is stored in output buffer. The with_AlgCurve flag will include a header that has the Algorithm and Curve information.

Parameters:

  • key Pointer to ECC key
  • output Pointer to output buffer to write to.
  • inLen Size of buffer.
  • with_AlgCurve a flag for when to include a header that has the Algorithm and Curve information.

See:

Return:

  • 0 Success, size of buffer used

  • BAD_FUNC_ARG Returned if output or key is null.
  • LENGTH_ONLY_E Error in getting ECC public key size.
  • BUFFER_E Returned when output buffer is too small.

Example

ecc_key key;
wc_ecc_init(&key);
WC_WC_RNG rng;
wc_InitRng(&rng);
wc_ecc_make_key(&rng, 32, &key);
int derSz = // Some appropriate size for der;
byte der[derSz];

if(wc_EccPublicKeyToDer(&key, der, derSz, 1) < 0)
{
    // Error converting ECC public key to der
}

function wc_EccPublicKeyToDer_ex

int wc_EccPublicKeyToDer_ex(
    ecc_key * key,
    byte * output,
    word32 inLen,
    int with_AlgCurve,
    int comp
)

This function converts the ECC public key to DER format. It returns the size of buffer used. The public ECC key in DER format is stored in output buffer. The with_AlgCurve flag will include a header that has the Algorithm and Curve information. The comp parameter determines if the public key will be exported as compressed.

Parameters:

  • key Pointer to ECC key
  • output Pointer to output buffer to write to.
  • inLen Size of buffer.
  • with_AlgCurve a flag for when to include a header that has the Algorithm and Curve information.
  • comp If 1 (non-zero) the ECC public key will be written in compressed form. If 0 it will be written in an uncompressed format.

See:

Return:

  • 0 Success, size of buffer used

  • BAD_FUNC_ARG Returned if output or key is null.
  • LENGTH_ONLY_E Error in getting ECC public key size.
  • BUFFER_E Returned when output buffer is too small.

Example

ecc_key key;
wc_ecc_init(&key);
WC_WC_RNG rng;
wc_InitRng(&rng);
wc_ecc_make_key(&rng, 32, &key);
int derSz = // Some appropriate size for der;
byte der[derSz];

// Write out a compressed ECC key
if(wc_EccPublicKeyToDer_ex(&key, der, derSz, 1, 1) < 0)
{
    // Error converting ECC public key to der
}

function wc_EncodeSignature

word32 wc_EncodeSignature(
    byte * out,
    const byte * digest,
    word32 digSz,
    int hashOID
)

This function encodes a digital signature into the output buffer, and returns the size of the encoded signature created.

Parameters:

  • out pointer to the buffer where the encoded signature will be written
  • digest pointer to the digest to use to encode the signature
  • digSz the length of the buffer containing the digest
  • hashOID OID identifying the hash type used to generate the signature. Valid options, depending on build configurations, are: SHAh, SHA256h, SHA384h, SHA512h, MD2h, MD5h, DESb, DES3b, CTC_MD5wRSA, CTC_SHAwRSA, CTC_SHA256wRSA, CTC_SHA384wRSA, CTC_SHA512wRSA, CTC_SHAwECDSA, CTC_SHA256wECDSA, CTC_SHA384wECDSA, and CTC_SHA512wECDSA.

See: none

Return: Success On successfully writing the encoded signature to output, returns the length written to the buffer

int signSz;
byte encodedSig[MAX_ENCODED_SIG_SZ];
Sha256 sha256;
// initialize sha256 for hashing

byte* dig = = (byte*)malloc(SHA256_DIGEST_SIZE);
// perform hashing and hash updating so dig stores SHA-256 hash
// (see wc_InitSha256, wc_Sha256Update and wc_Sha256Final)
signSz = wc_EncodeSignature(encodedSig, dig, SHA256_DIGEST_SIZE,SHA256h);

function wc_GetCTC_HashOID

int wc_GetCTC_HashOID(
    int type
)

This function returns the hash OID that corresponds to a hashing type. For example, when given the type: SHA512, this function returns the identifier corresponding to a SHA512 hash, SHA512h.

Parameters:

  • type the hash type for which to find the OID. Valid options, depending on build configuration, include: MD2, MD5, SHA, SHA256, SHA512, SHA384, and SHA512.

See: none

Return:

  • Success On success, returns the OID corresponding to the appropriate hash to use with that encryption type.
  • 0 Returned if an unrecognized hash type is passed in as argument.

Example

int hashOID;

hashOID = wc_GetCTC_HashOID(SHA512);
if (hashOID == 0) {
    // WOLFSSL_SHA512 not defined
}

function wc_SetCert_Free

void wc_SetCert_Free(
    Cert * cert
)

This function cleans up memory and resources used by the certificate structure's decoded cert cache. When WOLFSSL_CERT_GEN_CACHE is defined the decoded cert structure is cached in the certificate structure. This allows subsequent calls to certificate set functions to avoid parsing the decoded cert on each call.

Parameters:

  • cert pointer to an uninitialized certificate information structure.

See:

Return:

  • 0 on success.
  • BAD_FUNC_ARG Returned if invalid pointer is passed in as argument.

Example

Cert cert; // Initialized certificate structure

wc_SetCert_Free(&cert);

function wc_GetPkcs8TraditionalOffset

int wc_GetPkcs8TraditionalOffset(
    byte * input,
    word32 * inOutIdx,
    word32 sz
)

This function finds the beginning of the traditional private key inside a PKCS#8 unencrypted buffer.

Parameters:

  • input Buffer containing unencrypted PKCS#8 private key.
  • inOutIdx Index into the input buffer. On input, it should be a byte offset to the beginning of the the PKCS#8 buffer. On output, it will be the byte offset to the traditional private key within the input buffer.
  • sz The number of bytes in the input buffer.

See:

Return:

  • Length of traditional private key on success.
  • Negative values on failure.

Example

byte* pkcs8Buf; // Buffer containing PKCS#8 key.
word32 idx = 0;
word32 sz; // Size of pkcs8Buf.
...
ret = wc_GetPkcs8TraditionalOffset(pkcs8Buf, &idx, sz);
// pkcs8Buf + idx is now the beginning of the traditional private key bytes.

function wc_CreatePKCS8Key

int wc_CreatePKCS8Key(
    byte * out,
    word32 * outSz,
    byte * key,
    word32 keySz,
    int algoID,
    const byte * curveOID,
    word32 oidSz
)

This function takes in a DER private key and converts it to PKCS#8 format. Also used in creating PKCS#12 shrouded key bags. See RFC 5208.

Parameters:

  • out Buffer to place result in. If NULL, required out buffer size returned in outSz.
  • outSz Size of out buffer.
  • key Buffer with traditional DER key.
  • keySz Size of key buffer.
  • algoID Algorithm ID (e.g. RSAk).
  • curveOID ECC curve OID if used. Should be NULL for RSA keys.
  • oidSz Size of curve OID. Is set to 0 if curveOID is NULL.

See:

Return:

  • The size of the PKCS#8 key placed into out on success.
  • LENGTH_ONLY_E if out is NULL, with required output buffer size in outSz.
  • Other negative values on failure.

Example

ecc_key eccKey;              // wolfSSL ECC key object.
byte* der;                   // DER-encoded ECC key.
word32 derSize;              // Size of der.
const byte* curveOid = NULL; // OID of curve used by eccKey.
word32 curveOidSz = 0;       // Size of curve OID.
byte* pkcs8;                 // Output buffer for PKCS#8 key.
word32 pkcs8Sz;              // Size of output buffer.

derSize = wc_EccKeyDerSize(&eccKey, 1);
...
derSize = wc_EccKeyToDer(&eccKey, der, derSize);
...
ret = wc_ecc_get_oid(eccKey.dp->oidSum, &curveOid, &curveOidSz);
...
ret = wc_CreatePKCS8Key(NULL, &pkcs8Sz, der,
    derSize, ECDSAk, curveOid, curveOidSz); // Get size needed in pkcs8Sz.
...
ret = wc_CreatePKCS8Key(pkcs8, &pkcs8Sz, der,
    derSize, ECDSAk, curveOid, curveOidSz);

function wc_EncryptPKCS8Key

int wc_EncryptPKCS8Key(
    byte * key,
    word32 keySz,
    byte * out,
    word32 * outSz,
    const char * password,
    int passwordSz,
    int vPKCS,
    int pbeOid,
    int encAlgId,
    byte * salt,
    word32 saltSz,
    int itt,
    WC_RNG * rng,
    void * heap
)

This function takes in an unencrypted PKCS#8 DER key (e.g. one created by wc_CreatePKCS8Key) and converts it to PKCS#8 encrypted format. The resulting encrypted key can be decrypted using wc_DecryptPKCS8Key. See RFC 5208.

Parameters:

  • key Buffer with traditional DER key.
  • keySz Size of key buffer.
  • out Buffer to place result in. If NULL, required out buffer size returned in outSz.
  • outSz Size of out buffer.
  • password The password to use for the password-based encryption algorithm.
  • passwordSz The length of the password (not including the NULL terminator).
  • vPKCS The PKCS version to use. Can be 1 for PKCS12 or PKCS5.
  • pbeOid The OID of the PBE scheme to use (e.g. PBES2 or one of the OIDs for PBES1 in RFC 2898 A.3).
  • encAlgId The encryption algorithm ID to use (e.g. AES256CBCb).
  • salt The salt buffer to use. If NULL, a random salt will be used.
  • saltSz The length of the salt buffer. Can be 0 if passing NULL for salt.
  • itt The number of iterations to use for the KDF.
  • rng A pointer to an initialized WC_RNG object.
  • heap A pointer to the heap used for dynamic allocation. Can be NULL.

See:

Return:

  • The size of the encrypted key placed in out on success.
  • LENGTH_ONLY_E if out is NULL, with required output buffer size in outSz.
  • Other negative values on failure.

Example

byte* pkcs8;          // Unencrypted PKCS#8 key.
word32 pkcs8Sz;       // Size of pkcs8.
byte* pkcs8Enc;       // Encrypted PKCS#8 key.
word32 pkcs8EncSz;    // Size of pkcs8Enc.
const char* password; // Password to use for encryption.
int passwordSz;       // Length of password (not including NULL terminator).
WC_RNG rng;

// The following produces an encrypted version of pkcs8 in pkcs8Enc. The
// encryption uses password-based encryption scheme 2 (PBE2) from PKCS#5 and
// the AES cipher in CBC mode with a 256-bit key. See RFC 8018 for more on
// PKCS#5.
ret = wc_EncryptPKCS8Key(pkcs8, pkcs8Sz, pkcs8Enc, &pkcs8EncSz, password,
        passwordSz, PKCS5, PBES2, AES256CBCb, NULL, 0,
        WC_PKCS12_ITT_DEFAULT, &rng, NULL);

function wc_DecryptPKCS8Key

int wc_DecryptPKCS8Key(
    byte * input,
    word32 sz,
    const char * password,
    int passwordSz
)

This function takes an encrypted PKCS#8 DER key and decrypts it to PKCS#8 unencrypted DER. Undoes the encryption done by wc_EncryptPKCS8Key. See RFC5208. The input buffer is overwritten with the decrypted data.

Parameters:

  • input On input, buffer containing encrypted PKCS#8 key. On successful output, contains the decrypted key.
  • sz Size of the input buffer.
  • password The password used to encrypt the key.
  • passwordSz The length of the password (not including NULL terminator).

See:

Return:

  • The length of the decrypted buffer on success.
  • Negative values on failure.

Example

byte* pkcs8Enc;       // Encrypted PKCS#8 key made with wc_EncryptPKCS8Key.
word32 pkcs8EncSz;    // Size of pkcs8Enc.
const char* password; // Password to use for decryption.
int passwordSz;       // Length of password (not including NULL terminator).

ret = wc_DecryptPKCS8Key(pkcs8Enc, pkcs8EncSz, password, passwordSz);

function wc_CreateEncryptedPKCS8Key

int wc_CreateEncryptedPKCS8Key(
    byte * key,
    word32 keySz,
    byte * out,
    word32 * outSz,
    const char * password,
    int passwordSz,
    int vPKCS,
    int pbeOid,
    int encAlgId,
    byte * salt,
    word32 saltSz,
    int itt,
    WC_RNG * rng,
    void * heap
)

This function takes a traditional, DER key, converts it to PKCS#8 format, and encrypts it. It uses wc_CreatePKCS8Key and wc_EncryptPKCS8Key to do this.

Parameters:

  • key Buffer with traditional DER key.
  • keySz Size of key buffer.
  • out Buffer to place result in. If NULL, required out buffer size returned in outSz.
  • outSz Size of out buffer.
  • password The password to use for the password-based encryption algorithm.
  • passwordSz The length of the password (not including the NULL terminator).
  • vPKCS The PKCS version to use. Can be 1 for PKCS12 or PKCS5.
  • pbeOid The OID of the PBE scheme to use (e.g. PBES2 or one of the OIDs for PBES1 in RFC 2898 A.3).
  • encAlgId The encryption algorithm ID to use (e.g. AES256CBCb).
  • salt The salt buffer to use. If NULL, a random salt will be used.
  • saltSz The length of the salt buffer. Can be 0 if passing NULL for salt.
  • itt The number of iterations to use for the KDF.
  • rng A pointer to an initialized WC_RNG object.
  • heap A pointer to the heap used for dynamic allocation. Can be NULL.

See:

Return:

  • The size of the encrypted key placed in out on success.
  • LENGTH_ONLY_E if out is NULL, with required output buffer size in outSz.
  • Other negative values on failure.

Example

byte* key;            // Traditional private key (DER formatted).
word32 keySz;         // Size of key.
byte* pkcs8Enc;       // Encrypted PKCS#8 key.
word32 pkcs8EncSz;    // Size of pkcs8Enc.
const char* password; // Password to use for encryption.
int passwordSz;       // Length of password (not including NULL terminator).
WC_RNG rng;

// The following produces an encrypted, PKCS#8 version of key in pkcs8Enc.
// The encryption uses password-based encryption scheme 2 (PBE2) from PKCS#5
// and the AES cipher in CBC mode with a 256-bit key. See RFC 8018 for more
// on PKCS#5.
ret = wc_CreateEncryptedPKCS8Key(key, keySz, pkcs8Enc, &pkcs8EncSz,
        password, passwordSz, PKCS5, PBES2, AES256CBCb, NULL, 0,
        WC_PKCS12_ITT_DEFAULT, &rng, NULL);

function wc_InitDecodedCert

void wc_InitDecodedCert(
    struct DecodedCert * cert,
    const byte * source,
    word32 inSz,
    void * heap
)

This function initializes the DecodedCert pointed to by the "cert" parameter. It saves the "source" pointer to a DER-encoded certificate of length "inSz." This certificate can be parsed by a subsequent call to wc_ParseCert.

Parameters:

  • cert Pointer to an allocated DecodedCert object.
  • source Pointer to a DER-encoded certificate.
  • inSz Length of the DER-encoded certificate in bytes.
  • heap A pointer to the heap used for dynamic allocation. Can be NULL.

See:

Example

DecodedCert decodedCert; // Decoded certificate object.
byte* certBuf;           // DER-encoded certificate buffer.
word32 certBufSz;        // Size of certBuf in bytes.

wc_InitDecodedCert(&decodedCert, certBuf, certBufSz, NULL);

function wc_ParseCert

int wc_ParseCert(
    DecodedCert * cert,
    int type,
    int verify,
    void * cm
)

This function parses the DER-encoded certificate saved in the DecodedCert object and populates the fields of that object. The DecodedCert must have been initialized with a prior call to wc_InitDecodedCert. This function takes an optional pointer to a CertificateManager object, which is used to populate the certificate authority information of the DecodedCert, if the CA is found in the CertificateManager.

Parameters:

  • cert Pointer to an initialized DecodedCert object.
  • type Type of certificate. See the CertType enum in asn_public.h.
  • verify Flag that, if set, indicates the user wants to verify the validity of the certificate.
  • cm An optional pointer to a CertificateManager. Can be NULL.

See:

Return:

  • 0 on success.
  • Other negative values on failure.

Example

int ret;
DecodedCert decodedCert; // Decoded certificate object.
byte* certBuf;           // DER-encoded certificate buffer.
word32 certBufSz;        // Size of certBuf in bytes.

wc_InitDecodedCert(&decodedCert, certBuf, certBufSz, NULL);
ret = wc_ParseCert(&decodedCert, CERT_TYPE, NO_VERIFY, NULL);
if (ret != 0) {
    fprintf(stderr, "wc_ParseCert failed.\n");
}

function wc_FreeDecodedCert

void wc_FreeDecodedCert(
    struct DecodedCert * cert
)

This function frees a DecodedCert that was previously initialized with wc_InitDecodedCert.

Parameters:

  • cert Pointer to an initialized DecodedCert object.

See:

Example

int ret;
DecodedCert decodedCert; // Decoded certificate object.
byte* certBuf;           // DER-encoded certificate buffer.
word32 certBufSz;        // Size of certBuf in bytes.

wc_InitDecodedCert(&decodedCert, certBuf, certBufSz, NULL);
ret = wc_ParseCert(&decodedCert, CERT_TYPE, NO_VERIFY, NULL);
if (ret != 0) {
    fprintf(stderr, "wc_ParseCert failed.\n");
}
wc_FreeDecodedCert(&decodedCert);

function wc_SetTimeCb

int wc_SetTimeCb(
    wc_time_cb f
)

This function registers a time callback that will be used anytime wolfSSL needs to get the current time. The prototype of the callback should be the same as the "time" function from the C standard library.

Parameters:

  • f function to register as the time callback.

See: wc_Time

Return: 0 Returned on success.

Example

int ret = 0;
// Time callback prototype
time_t my_time_cb(time_t* t);
// Register it
ret = wc_SetTimeCb(my_time_cb);
if (ret != 0) {
    // failed to set time callback
}
time_t my_time_cb(time_t* t)
{
    // custom time function
}

function wc_Time

time_t wc_Time(
    time_t * t
)

This function gets the current time. By default, it uses the XTIME macro, which varies between platforms. The user can use a function of their choosing instead via the wc_SetTimeCb function.

Parameters:

  • t Optional time_t pointer to populate with current time.

See: wc_SetTimeCb

Return: Time Current time returned on success.

Example

time_t currentTime = 0;
currentTime = wc_Time(NULL);
wc_Time(&currentTime);

function wc_SetCustomExtension

int wc_SetCustomExtension(
    Cert * cert,
    int critical,
    const char * oid,
    const byte * der,
    word32 derSz
)

This function injects a custom extension in to an X.509 certificate.

Parameters:

  • cert Pointer to an initialized DecodedCert object.
  • critical If 0, the extension will not be marked critical, otherwise it will be marked critical.
  • oid Dot separted oid as a string. For example "1.2.840.10045.3.1.7"
  • der The der encoding of the content of the extension.
  • derSz The size in bytes of the der encoding.

See:

Return:

  • 0 Returned on success.
  • Other negative values on failure.

Example

int ret = 0;
Cert newCert;
wc_InitCert(&newCert);

// Code to setup subject, public key, issuer, and other things goes here.

ret = wc_SetCustomExtension(&newCert, 1, "1.2.3.4.5",
          (const byte *)"This is a critical extension", 28);
if (ret < 0) {
    // Failed to set the extension.
}

ret = wc_SetCustomExtension(&newCert, 0, "1.2.3.4.6",
          (const byte *)"This is NOT a critical extension", 32)
if (ret < 0) {
    // Failed to set the extension.
}

// Code to sign the certificate and then write it out goes here.

function wc_SetUnknownExtCallback

WOLFSSL_ASN_API int wc_SetUnknownExtCallback(
    DecodedCert * cert,
    wc_UnknownExtCallback cb
)

This function registers a callback that will be used anytime wolfSSL encounters an unknown X.509 extension in a certificate while parsing a certificate. The prototype of the callback should be:

Parameters:

  • cert the DecodedCert struct that is to be associated with this callback.
  • cb function to register as the time callback.

See:

Return:

  • 0 Returned on success.
  • Other negative values on failure.

Example

int ret = 0;
// Unkown extension callback prototype
int myUnknownExtCallback(const word16* oid, word32 oidSz, int crit,
                         const unsigned char* der, word32 derSz);

// Register it
ret = wc_SetUnknownExtCallback(cert, myUnknownExtCallback);
if (ret != 0) {
    // failed to set the callback
}

// oid: Array of integers that are the dot separated values in an oid.
// oidSz: Number of values in oid.
// crit: Whether the extension was mark critical.
// der: The der encoding of the content of the extension.
// derSz: The size in bytes of the der encoding.
int myCustomExtCallback(const word16* oid, word32 oidSz, int crit,
                        const unsigned char* der, word32 derSz) {

    // Logic to parse extension goes here.

    // NOTE: by returning zero, we are accepting this extension and
    // informing wolfSSL that it is acceptable. If you find an extension
    // that you do not find acceptable, you should return an error. The
    // standard behavior upon encountering an unknown extension with the
    // critical flag set is to return ASN_CRIT_EXT_E. For the sake of
    // brevity, this example is always accepting every extension; you
    // should use different logic.
    return 0;
}

Updated on 2022-07-07 at 08:31:02 +0000