X.509 module#

mbedtls_x509_buf#

typedef mbedtls_asn1_buf mbedtls_x509_buf

Type-length-value structure that allows for ASN1 using DER.

mbedtls_x509_bitstring#

typedef mbedtls_asn1_bitstring mbedtls_x509_bitstring

Container for ASN1 bit strings.

mbedtls_x509_name#

typedef mbedtls_asn1_named_data mbedtls_x509_name

Container for ASN1 named information objects.

It allows for Relative Distinguished Names (e.g. cn=localhost,ou=code,etc.).

mbedtls_x509_sequence#

typedef mbedtls_asn1_sequence mbedtls_x509_sequence

Container for a sequence of ASN.1 items.

mbedtls_x509_crt_restart_ctx#

typedef void mbedtls_x509_crt_restart_ctx

mbedtls_x509_crt_ext_cb_t#

typedef int(* mbedtls_x509_crt_ext_cb_t) (void *p_ctx, mbedtls_x509_crt const *crt, mbedtls_x509_buf const *oid, int critical, const unsigned char *p, const unsigned char *end) )(void *p_ctx, mbedtls_x509_crt const *crt, mbedtls_x509_buf const *oid, int critical, const unsigned char *p, const unsigned char *end)

The type of certificate extension callbacks.

            Callbacks of this type are passed to and used by the
            mbedtls_x509_crt_parse_der_with_ext_cb() routine when
            it encounters either an unsupported extension or a
            "certificate policies" extension containing any
            unsupported certificate policies.
            Future versions of the library may invoke the callback
            in other cases, if and when the need arises.

Note

• The callback must fail and return a negative error code if it can not parse or does not support the extension. When the callback fails to parse a critical extension mbedtls_x509_crt_parse_der_with_ext_cb() also fails. When the callback fails to parse a non critical extension mbedtls_x509_crt_parse_der_with_ext_cb() simply skips the extension and continues parsing.

Returns

• 0 on success.

• A negative error code on failure.

mbedtls_x509_crt_ca_cb_t#

typedef int(* mbedtls_x509_crt_ca_cb_t) (void *p_ctx, mbedtls_x509_crt const *child, mbedtls_x509_crt **candidate_cas) )(void *p_ctx, mbedtls_x509_crt const *child, mbedtls_x509_crt **candidate_cas)

The type of trusted certificate callbacks.

                 Callbacks of this type are passed to and used by the CRT
                 verification routine mbedtls_x509_crt_verify_with_ca_cb()
                 when looking for trusted signers of a given certificate.

                 On success, the callback returns a list of trusted
                 certificates to be considered as potential signers
                 for the input certificate.

Note

• The callback must only return a non-zero value on a fatal error. If, in contrast, the search for a potential signer completes without a single candidate, the callback must return 0 and set *candidate_cas to NULL.

Returns

• 0 on success. In this case, *candidate_cas points to a heap-allocated linked list of instances of mbedtls_x509_crt, and ownership of this list is passed to the caller.

• A negative error code on failure.

mbedtls_x509_crt_profile_default#

const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_default

Default security profile.

Should provide a good balance between security and compatibility with current deployments.

This profile permits:

• SHA2 hashes with at least 256 bits: SHA-256, SHA-384, SHA-512.

• Elliptic curves with 255 bits and above except secp256k1.

• RSA with 2048 bits and above.

New minor versions of Mbed TLS may extend this profile, for example if new algorithms are added to the library. New minor versions of Mbed TLS will not reduce this profile unless serious security concerns require it.

mbedtls_x509_crt_profile_next#

const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_next

Expected next default profile.

Recommended for new deployments. Currently targets a 128-bit security level, except for allowing RSA-2048. This profile may change at any time.

mbedtls_x509_crt_profile_suiteb#

const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_suiteb

NSA Suite B profile.

mbedtls_x509_crt_profile_none#

const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_none

Empty profile that allows nothing.

Useful as a basis for constructing custom profiles.

mbedtls_x509write_crt_set_subject_alternative_name#

int mbedtls_x509write_crt_set_subject_alternative_name (mbedtls_x509write_cert *ctx, const mbedtls_x509_san_list *san_list)

Set Subject Alternative Name.

Returns

• 0 if successful, or MBEDTLS_ERR_X509_ALLOC_FAILED

Note

• "dnsName", "uniformResourceIdentifier", "IP address", "otherName", and "DirectoryName", as defined in RFC 5280, are supported.

mbedtls_x509_crt_parse_der#

int mbedtls_x509_crt_parse_der (mbedtls_x509_crt *chain, const unsigned char *buf, size_t buflen)

Parse a single DER formatted certificate and add it to the end of the provided chained list.

Note

• If #MBEDTLS_USE_PSA_CRYPTO is enabled, the PSA crypto subsystem must have been initialized by calling psa_crypto_init() before calling this function.

Note

• This function makes an internal copy of the CRT buffer buf. In particular, buf may be destroyed or reused after this call returns. To avoid duplicating the CRT buffer (at the cost of stricter lifetime constraints), use mbedtls_x509_crt_parse_der_nocopy() instead.

Returns

• 0 if successful.

• A negative error code on failure.

mbedtls_x509_crt_parse_der_with_ext_cb#

int mbedtls_x509_crt_parse_der_with_ext_cb (mbedtls_x509_crt *chain, const unsigned char *buf, size_t buflen, int make_copy, mbedtls_x509_crt_ext_cb_t cb, void *p_ctx)

Parse a single DER formatted certificate and add it to the end of the provided chained list.

Note

• If #MBEDTLS_USE_PSA_CRYPTO is enabled, the PSA crypto subsystem must have been initialized by calling psa_crypto_init() before calling this function.

Note

• This call is functionally equivalent to mbedtls_x509_crt_parse_der(), and/or mbedtls_x509_crt_parse_der_nocopy() but it calls the callback with every unsupported certificate extension and additionally the "certificate policies" extension if it contains any unsupported certificate policies. The callback must return a negative error code if it does not know how to handle such an extension. When the callback fails to parse a critical extension mbedtls_x509_crt_parse_der_with_ext_cb() also fails. When the callback fails to parse a non critical extension mbedtls_x509_crt_parse_der_with_ext_cb() simply skips the extension and continues parsing. Future versions of the library may invoke the callback in other cases, if and when the need arises.

Returns

• 0 if successful.

• A negative error code on failure.

mbedtls_x509_crt_parse_der_nocopy#

int mbedtls_x509_crt_parse_der_nocopy (mbedtls_x509_crt *chain, const unsigned char *buf, size_t buflen)

Parse a single DER formatted certificate and add it to the end of the provided chained list.

This is a variant of mbedtls_x509_crt_parse_der() which takes temporary ownership of the CRT buffer until the CRT is destroyed.

Note

• If #MBEDTLS_USE_PSA_CRYPTO is enabled, the PSA crypto subsystem must have been initialized by calling psa_crypto_init() before calling this function.

Note

• This call is functionally equivalent to mbedtls_x509_crt_parse_der(), but it avoids creating a copy of the input buffer at the cost of stronger lifetime constraints. This is useful in constrained environments where duplication of the CRT cannot be tolerated.

Returns

• 0 if successful.

• A negative error code on failure.

mbedtls_x509_crt_parse#

int mbedtls_x509_crt_parse (mbedtls_x509_crt *chain, const unsigned char *buf, size_t buflen)

Parse one DER-encoded or one or more concatenated PEM-encoded certificates and add them to the chained list.

For CRTs in PEM encoding, the function parses permissively: if at least one certificate can be parsed, the function returns the number of certificates for which parsing failed (hence 0 if all certificates were parsed successfully). If no certificate could be parsed, the function returns the first (negative) error encountered during parsing.

PEM encoded certificates may be interleaved by other data such as human readable descriptions of their content, as long as the certificates are enclosed in the PEM specific '--—{BEGIN/END} CERTIFICATE--—' delimiters.

Note

• If #MBEDTLS_USE_PSA_CRYPTO is enabled, the PSA crypto subsystem must have been initialized by calling psa_crypto_init() before calling this function.

Returns

• 0 if all certificates were parsed successfully.

• The (positive) number of certificates that couldn't be parsed if parsing was partly successful (see above).

• A negative X509 or PEM error code otherwise.

mbedtls_x509_crt_info#

int mbedtls_x509_crt_info (char *buf, size_t size, const char *prefix, const mbedtls_x509_crt *crt)

Returns an informational string about the certificate.

Returns

• The length of the string written (not including the terminated nul byte), or a negative error code.

mbedtls_x509_crt_verify_info#

int mbedtls_x509_crt_verify_info (char *buf, size_t size, const char *prefix, uint32_t flags)

Returns an informational string about the verification status of a certificate.

Returns

• The length of the string written (not including the terminated nul byte), or a negative error code.

mbedtls_x509_crt_verify#

int mbedtls_x509_crt_verify (mbedtls_x509_crt *crt, mbedtls_x509_crt *trust_ca, mbedtls_x509_crl *ca_crl, const char *cn, uint32_t *flags, int(*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *), void *p_vrfy)

Verify a chain of certificates.

            The verify callback is a user-supplied callback that
            can clear / modify / add flags for a certificate. If set,
            the verification callback is called for each
            certificate in the chain (from the trust-ca down to the
            presented crt). The parameters for the callback are:
            (void *parameter, mbedtls_x509_crt *crt, int certificate_depth,
            int *flags). With the flags representing current flags for
            that specific certificate and the certificate depth from
            the bottom (Peer cert depth = 0).

            All flags left after returning from the callback
            are also returned to the application. The function should
            return 0 for anything (including invalid certificates)
            other than fatal error, as a non-zero return code
            immediately aborts the verification process. For fatal
            errors, a specific error code should be used (different
            from MBEDTLS_ERR_X509_CERT_VERIFY_FAILED which should not
            be returned at this point), or MBEDTLS_ERR_X509_FATAL_ERROR
            can be used if no better code is available.

Note

• In case verification failed, the results can be displayed using mbedtls_x509_crt_verify_info()

• Same as mbedtls_x509_crt_verify_with_profile() with the default security profile.

• It is your responsibility to provide up-to-date CRLs for all trusted CAs. If no CRL is provided for the CA that was used to sign the certificate, CRL verification is skipped silently, that is without setting any flag.

• The trust_ca list can contain two types of certificates: (1) those of trusted root CAs, so that certificates chaining up to those CAs will be trusted, and (2) self-signed end-entity certificates to be trusted (for specific peers you know) - in that case, the self-signed certificate doesn't need to have the CA bit set.

Returns

• 0 if the chain is valid with respect to the passed CN, CAs, CRLs and security profile.

• MBEDTLS_ERR_X509_CERT_VERIFY_FAILED in case the certificate chain verification failed. In this case, *flags will have one or more MBEDTLS_X509_BADCERT_XXX or MBEDTLS_X509_BADCRL_XXX flags set.

• Another negative error code in case of a fatal error encountered during the verification process.

mbedtls_x509_crt_verify_with_profile#

int mbedtls_x509_crt_verify_with_profile (mbedtls_x509_crt *crt, mbedtls_x509_crt *trust_ca, mbedtls_x509_crl *ca_crl, const mbedtls_x509_crt_profile *profile, const char *cn, uint32_t *flags, int(*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *), void *p_vrfy)

Verify a chain of certificates with respect to a configurable security profile.

Note

• Same as mbedtls_x509_crt_verify(), but with explicit security profile.

• The restrictions on keys (RSA minimum size, allowed curves for ECDSA) apply to all certificates: trusted root, intermediate CAs if any, and end entity certificate.

Returns

• 0 if the chain is valid with respect to the passed CN, CAs, CRLs and security profile.

• MBEDTLS_ERR_X509_CERT_VERIFY_FAILED in case the certificate chain verification failed. In this case, *flags will have one or more MBEDTLS_X509_BADCERT_XXX or MBEDTLS_X509_BADCRL_XXX flags set.

• Another negative error code in case of a fatal error encountered during the verification process.

mbedtls_x509_crt_verify_restartable#

int mbedtls_x509_crt_verify_restartable (mbedtls_x509_crt *crt, mbedtls_x509_crt *trust_ca, mbedtls_x509_crl *ca_crl, const mbedtls_x509_crt_profile *profile, const char *cn, uint32_t *flags, int(*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *), void *p_vrfy, mbedtls_x509_crt_restart_ctx *rs_ctx)

Restartable version of mbedtls_crt_verify_with_profile()

Note

• Performs the same job as mbedtls_crt_verify_with_profile() but can return early and restart according to the limit set with mbedtls_ecp_set_max_ops() to reduce blocking.

Returns

• See mbedtls_crt_verify_with_profile(), or

• #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of operations was reached: see mbedtls_ecp_set_max_ops().

mbedtls_x509_crt_check_key_usage#

int mbedtls_x509_crt_check_key_usage (const mbedtls_x509_crt *crt, unsigned int usage)

Check usage of certificate against keyUsage extension.

Note

• Except for decipherOnly and encipherOnly, a bit set in the usage argument means this bit MUST be set in the certificate. For decipherOnly and encipherOnly, it means that bit MAY be set.

Returns

• 0 is these uses of the certificate are allowed, MBEDTLS_ERR_X509_BAD_INPUT_DATA if the keyUsage extension is present but does not match the usage argument.

Note

• You should only call this function on leaf certificates, on (intermediate) CAs the keyUsage extension is automatically checked by mbedtls_x509_crt_verify().

mbedtls_x509_crt_check_extended_key_usage#

int mbedtls_x509_crt_check_extended_key_usage (const mbedtls_x509_crt *crt, const char *usage_oid, size_t usage_len)

Check usage of certificate against extendedKeyUsage.

Returns

• 0 if this use of the certificate is allowed, MBEDTLS_ERR_X509_BAD_INPUT_DATA if not.

Note

• Usually only makes sense on leaf certificates.

mbedtls_x509_crt_is_revoked#

int mbedtls_x509_crt_is_revoked (const mbedtls_x509_crt *crt, const mbedtls_x509_crl *crl)

Verify the certificate revocation status.

Returns

• 1 if the certificate is revoked, 0 otherwise

mbedtls_x509_crt_init#

void mbedtls_x509_crt_init (mbedtls_x509_crt *crt)

Initialize a certificate (chain)

mbedtls_x509_crt_free#

void mbedtls_x509_crt_free (mbedtls_x509_crt *crt)

Unallocate all certificate data.

mbedtls_x509_crt_has_ext_type#

static int mbedtls_x509_crt_has_ext_type (const mbedtls_x509_crt *ctx, int ext_type)

Query certificate for given extension type.

Returns

• 0 if the given extension type is not present, non-zero otherwise

MBEDTLS_X509_ID_FLAG#

#define MBEDTLS_X509_ID_FLAG

(id)

Build flag from an algorithm/curve identifier (pk, md, ecp) Since 0 is always XXX_NONE, ignore it.

MBEDTLS_X509_CRT_VERSION_1#

#define MBEDTLS_X509_CRT_VERSION_1

0

MBEDTLS_X509_CRT_VERSION_2#

#define MBEDTLS_X509_CRT_VERSION_2

1

MBEDTLS_X509_CRT_VERSION_3#

#define MBEDTLS_X509_CRT_VERSION_3

2

MBEDTLS_X509_RFC5280_MAX_SERIAL_LEN#

#define MBEDTLS_X509_RFC5280_MAX_SERIAL_LEN

20

MBEDTLS_X509_RFC5280_UTC_TIME_LEN#

#define MBEDTLS_X509_RFC5280_UTC_TIME_LEN

15

MBEDTLS_X509_MAX_FILE_PATH_LEN#

#define MBEDTLS_X509_MAX_FILE_PATH_LEN

512

MBEDTLS_X509_CRT_ERROR_INFO_LIST#

#define MBEDTLS_X509_CRT_ERROR_INFO_LIST

MBEDTLS_X509_MAX_VERIFY_CHAIN_SIZE#

#define MBEDTLS_X509_MAX_VERIFY_CHAIN_SIZE

(MBEDTLS_X509_MAX_INTERMEDIATE_CA + 2)

Max size of verification chain: end-entity + intermediates + trusted root.

mbedtls_x509_crl_parse_der#

int mbedtls_x509_crl_parse_der (mbedtls_x509_crl *chain, const unsigned char *buf, size_t buflen)

Parse a DER-encoded CRL and append it to the chained list.

Note

• If #MBEDTLS_USE_PSA_CRYPTO is enabled, the PSA crypto subsystem must have been initialized by calling psa_crypto_init() before calling this function.

Returns

• 0 if successful, or a specific X509 or PEM error code

mbedtls_x509_crl_parse#

int mbedtls_x509_crl_parse (mbedtls_x509_crl *chain, const unsigned char *buf, size_t buflen)

Parse one or more CRLs and append them to the chained list.

Note

• Multiple CRLs are accepted only if using PEM format

• If #MBEDTLS_USE_PSA_CRYPTO is enabled, the PSA crypto subsystem must have been initialized by calling psa_crypto_init() before calling this function.

Returns

• 0 if successful, or a specific X509 or PEM error code

mbedtls_x509_crl_info#

int mbedtls_x509_crl_info (char *buf, size_t size, const char *prefix, const mbedtls_x509_crl *crl)

Returns an informational string about the CRL.

Returns

• The length of the string written (not including the terminated nul byte), or a negative error code.

mbedtls_x509_crl_init#

void mbedtls_x509_crl_init (mbedtls_x509_crl *crl)

Initialize a CRL (chain)

mbedtls_x509_crl_free#

void mbedtls_x509_crl_free (mbedtls_x509_crl *crl)

Unallocate all CRL data.

mbedtls_x509_csr_parse_der#

int mbedtls_x509_csr_parse_der (mbedtls_x509_csr *csr, const unsigned char *buf, size_t buflen)

Load a Certificate Signing Request (CSR) in DER format.

Note

• CSR attributes (if any) are currently silently ignored.

• If #MBEDTLS_USE_PSA_CRYPTO is enabled, the PSA crypto subsystem must have been initialized by calling psa_crypto_init() before calling this function.

Returns

• 0 if successful, or a specific X509 error code

mbedtls_x509_csr_parse#

int mbedtls_x509_csr_parse (mbedtls_x509_csr *csr, const unsigned char *buf, size_t buflen)

Load a Certificate Signing Request (CSR), DER or PEM format.

Note

• See notes for mbedtls_x509_csr_parse_der()

• If #MBEDTLS_USE_PSA_CRYPTO is enabled, the PSA crypto subsystem must have been initialized by calling psa_crypto_init() before calling this function.

Returns

• 0 if successful, or a specific X509 or PEM error code

mbedtls_x509_csr_info#

int mbedtls_x509_csr_info (char *buf, size_t size, const char *prefix, const mbedtls_x509_csr *csr)

Returns an informational string about the CSR.

Returns

• The length of the string written (not including the terminated nul byte), or a negative error code.

mbedtls_x509_csr_init#

void mbedtls_x509_csr_init (mbedtls_x509_csr *csr)

Initialize a CSR.

mbedtls_x509_csr_free#

void mbedtls_x509_csr_free (mbedtls_x509_csr *csr)

Unallocate all CSR data.

MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE#

#define MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE

-0x2080

Unavailable feature, e.g.

RSA hashing/encryption combination.

MBEDTLS_ERR_X509_UNKNOWN_OID#

#define MBEDTLS_ERR_X509_UNKNOWN_OID

-0x2100

Requested OID is unknown.

MBEDTLS_ERR_X509_INVALID_FORMAT#

#define MBEDTLS_ERR_X509_INVALID_FORMAT

-0x2180

The CRT/CRL/CSR format is invalid, e.g.

different type expected.

MBEDTLS_ERR_X509_INVALID_VERSION#

#define MBEDTLS_ERR_X509_INVALID_VERSION

-0x2200

The CRT/CRL/CSR version element is invalid.

MBEDTLS_ERR_X509_INVALID_SERIAL#

#define MBEDTLS_ERR_X509_INVALID_SERIAL

-0x2280

The serial tag or value is invalid.

MBEDTLS_ERR_X509_INVALID_ALG#

#define MBEDTLS_ERR_X509_INVALID_ALG

-0x2300

The algorithm tag or value is invalid.

MBEDTLS_ERR_X509_INVALID_NAME#

#define MBEDTLS_ERR_X509_INVALID_NAME

-0x2380

The name tag or value is invalid.

MBEDTLS_ERR_X509_INVALID_DATE#

#define MBEDTLS_ERR_X509_INVALID_DATE

-0x2400

The date tag or value is invalid.

MBEDTLS_ERR_X509_INVALID_SIGNATURE#

#define MBEDTLS_ERR_X509_INVALID_SIGNATURE

-0x2480

The signature tag or value invalid.

MBEDTLS_ERR_X509_INVALID_EXTENSIONS#

#define MBEDTLS_ERR_X509_INVALID_EXTENSIONS

-0x2500

The extension tag or value is invalid.

MBEDTLS_ERR_X509_UNKNOWN_VERSION#

#define MBEDTLS_ERR_X509_UNKNOWN_VERSION

-0x2580

CRT/CRL/CSR has an unsupported version number.

MBEDTLS_ERR_X509_UNKNOWN_SIG_ALG#

#define MBEDTLS_ERR_X509_UNKNOWN_SIG_ALG

-0x2600

Signature algorithm (oid) is unsupported.

MBEDTLS_ERR_X509_SIG_MISMATCH#

#define MBEDTLS_ERR_X509_SIG_MISMATCH

-0x2680

Signature algorithms do not match.

(see mbedtls_x509_crt sig_oid)

MBEDTLS_ERR_X509_CERT_VERIFY_FAILED#

#define MBEDTLS_ERR_X509_CERT_VERIFY_FAILED

-0x2700

Certificate verification failed, e.g.

CRL, CA or signature check failed.

MBEDTLS_ERR_X509_CERT_UNKNOWN_FORMAT#

#define MBEDTLS_ERR_X509_CERT_UNKNOWN_FORMAT

-0x2780

Format not recognized as DER or PEM.

MBEDTLS_ERR_X509_BAD_INPUT_DATA#

#define MBEDTLS_ERR_X509_BAD_INPUT_DATA

-0x2800

Input invalid.

MBEDTLS_ERR_X509_ALLOC_FAILED#

#define MBEDTLS_ERR_X509_ALLOC_FAILED

-0x2880

Allocation of memory failed.

MBEDTLS_ERR_X509_FILE_IO_ERROR#

#define MBEDTLS_ERR_X509_FILE_IO_ERROR

-0x2900

Read/write of file failed.

MBEDTLS_ERR_X509_BUFFER_TOO_SMALL#

#define MBEDTLS_ERR_X509_BUFFER_TOO_SMALL

-0x2980

Destination buffer is too small.

MBEDTLS_ERR_X509_FATAL_ERROR#

#define MBEDTLS_ERR_X509_FATAL_ERROR

-0x3000

A fatal error occurred, eg the chain is too long or the vrfy callback failed.

MBEDTLS_X509_BADCERT_EXPIRED#

#define MBEDTLS_X509_BADCERT_EXPIRED

0x01

The certificate validity has expired.

MBEDTLS_X509_BADCERT_REVOKED#

#define MBEDTLS_X509_BADCERT_REVOKED

0x02

The certificate has been revoked (is on a CRL).

MBEDTLS_X509_BADCERT_CN_MISMATCH#

#define MBEDTLS_X509_BADCERT_CN_MISMATCH

0x04

The certificate Common Name (CN) does not match with the expected CN.

MBEDTLS_X509_BADCERT_NOT_TRUSTED#

#define MBEDTLS_X509_BADCERT_NOT_TRUSTED

0x08

The certificate is not correctly signed by the trusted CA.

MBEDTLS_X509_BADCRL_NOT_TRUSTED#

#define MBEDTLS_X509_BADCRL_NOT_TRUSTED

0x10

The CRL is not correctly signed by the trusted CA.

MBEDTLS_X509_BADCRL_EXPIRED#

#define MBEDTLS_X509_BADCRL_EXPIRED

0x20

The CRL is expired.

MBEDTLS_X509_BADCERT_MISSING#

#define MBEDTLS_X509_BADCERT_MISSING

0x40

Certificate was missing.

MBEDTLS_X509_BADCERT_SKIP_VERIFY#

#define MBEDTLS_X509_BADCERT_SKIP_VERIFY

0x80

Certificate verification was skipped.

MBEDTLS_X509_BADCERT_OTHER#

#define MBEDTLS_X509_BADCERT_OTHER

0x0100

Other reason (can be used by verify callback)

MBEDTLS_X509_BADCERT_FUTURE#

#define MBEDTLS_X509_BADCERT_FUTURE

0x0200

The certificate validity starts in the future.

MBEDTLS_X509_BADCRL_FUTURE#

#define MBEDTLS_X509_BADCRL_FUTURE

0x0400

The CRL is from the future.

MBEDTLS_X509_BADCERT_KEY_USAGE#

#define MBEDTLS_X509_BADCERT_KEY_USAGE

0x0800

Usage does not match the keyUsage extension.

MBEDTLS_X509_BADCERT_EXT_KEY_USAGE#

#define MBEDTLS_X509_BADCERT_EXT_KEY_USAGE

0x1000

Usage does not match the extendedKeyUsage extension.

MBEDTLS_X509_BADCERT_NS_CERT_TYPE#

#define MBEDTLS_X509_BADCERT_NS_CERT_TYPE

0x2000

Usage does not match the nsCertType extension.

MBEDTLS_X509_BADCERT_BAD_MD#

#define MBEDTLS_X509_BADCERT_BAD_MD

0x4000

The certificate is signed with an unacceptable hash.

MBEDTLS_X509_BADCERT_BAD_PK#

#define MBEDTLS_X509_BADCERT_BAD_PK

0x8000

The certificate is signed with an unacceptable PK alg (eg RSA vs ECDSA).

MBEDTLS_X509_BADCERT_BAD_KEY#

#define MBEDTLS_X509_BADCERT_BAD_KEY

0x010000

The certificate is signed with an unacceptable key (eg bad curve, RSA too short).

MBEDTLS_X509_BADCRL_BAD_MD#

#define MBEDTLS_X509_BADCRL_BAD_MD

0x020000

The CRL is signed with an unacceptable hash.

MBEDTLS_X509_BADCRL_BAD_PK#

#define MBEDTLS_X509_BADCRL_BAD_PK

0x040000

The CRL is signed with an unacceptable PK alg (eg RSA vs ECDSA).

MBEDTLS_X509_BADCRL_BAD_KEY#

#define MBEDTLS_X509_BADCRL_BAD_KEY

0x080000

The CRL is signed with an unacceptable key (eg bad curve, RSA too short).

mbedtls_x509write_csr_init#

void mbedtls_x509write_csr_init (mbedtls_x509write_csr *ctx)

Initialize a CSR context.

mbedtls_x509write_csr_set_subject_name#

int mbedtls_x509write_csr_set_subject_name (mbedtls_x509write_csr *ctx, const char *subject_name)

Set the subject name for a CSR Subject names should contain a comma-separated list of OID types and values: e.g.

"C=UK,O=ARM,CN=Mbed TLS Server 1"

Returns

• 0 if subject name was parsed successfully, or a specific error code

mbedtls_x509write_csr_set_key#

void mbedtls_x509write_csr_set_key (mbedtls_x509write_csr *ctx, mbedtls_pk_context *key)

Set the key for a CSR (public key will be included, private key used to sign the CSR when writing it)

mbedtls_x509write_csr_set_md_alg#

void mbedtls_x509write_csr_set_md_alg (mbedtls_x509write_csr *ctx, mbedtls_md_type_t md_alg)

Set the MD algorithm to use for the signature (e.g.

MBEDTLS_MD_SHA1)

mbedtls_x509write_csr_set_key_usage#

int mbedtls_x509write_csr_set_key_usage (mbedtls_x509write_csr *ctx, unsigned char key_usage)

Set the Key Usage Extension flags (e.g.

MBEDTLS_X509_KU_DIGITAL_SIGNATURE | MBEDTLS_X509_KU_KEY_CERT_SIGN)

Returns

• 0 if successful, or MBEDTLS_ERR_X509_ALLOC_FAILED

Note

• The decipherOnly flag from the Key Usage extension is represented by bit 8 (i.e. 0x8000), which cannot typically be represented in an unsigned char. Therefore, the flag decipherOnly (i.e. #MBEDTLS_X509_KU_DECIPHER_ONLY) cannot be set using this function.

mbedtls_x509write_csr_set_subject_alternative_name#

int mbedtls_x509write_csr_set_subject_alternative_name (mbedtls_x509write_csr *ctx, const mbedtls_x509_san_list *san_list)

Set Subject Alternative Name.

Returns

• 0 if successful, or MBEDTLS_ERR_X509_ALLOC_FAILED

Note

• Only "dnsName", "uniformResourceIdentifier" and "otherName", as defined in RFC 5280, are supported.

mbedtls_x509write_csr_set_ns_cert_type#

int mbedtls_x509write_csr_set_ns_cert_type (mbedtls_x509write_csr *ctx, unsigned char ns_cert_type)

Set the Netscape Cert Type flags (e.g.

MBEDTLS_X509_NS_CERT_TYPE_SSL_CLIENT | MBEDTLS_X509_NS_CERT_TYPE_EMAIL)

Returns

• 0 if successful, or MBEDTLS_ERR_X509_ALLOC_FAILED

mbedtls_x509write_csr_set_extension#

int mbedtls_x509write_csr_set_extension (mbedtls_x509write_csr *ctx, const char *oid, size_t oid_len, int critical, const unsigned char *val, size_t val_len)

Generic function to add to or replace an extension in the CSR.

Returns

• 0 if successful, or a MBEDTLS_ERR_X509_ALLOC_FAILED

mbedtls_x509write_csr_free#

void mbedtls_x509write_csr_free (mbedtls_x509write_csr *ctx)

Free the contents of a CSR context.

mbedtls_x509write_csr_der#

int mbedtls_x509write_csr_der (mbedtls_x509write_csr *ctx, unsigned char *buf, size_t size, int(*f_rng)(void *, unsigned char *, size_t), void *p_rng)

Write a CSR (Certificate Signing Request) to a DER structure Note: data is written at the end of the buffer! Use the return value to determine where you should start using the buffer.

Returns

• length of data written if successful, or a specific error code

Note

• f_rng is used for the signature operation.

mbedtls_x509write_csr_pem#

int mbedtls_x509write_csr_pem (mbedtls_x509write_csr *ctx, unsigned char *buf, size_t size, int(*f_rng)(void *, unsigned char *, size_t), void *p_rng)

Write a CSR (Certificate Signing Request) to a PEM string.

Returns

• 0 if successful, or a specific error code

Note

• f_rng is used for the signature operation.

mbedtls_x509_dn_gets#

int mbedtls_x509_dn_gets (char *buf, size_t size, const mbedtls_x509_name *dn)

Store the certificate DN in printable form into buf; no more than size characters will be written.

Returns

• The length of the string written (not including the terminated nul byte), or a negative error code.

mbedtls_x509_dn_get_next#

static mbedtls_x509_name * mbedtls_x509_dn_get_next (mbedtls_x509_name *dn)

Return the next relative DN in an X509 name.

Note

• Intended use is to compare function result to dn->next in order to detect boundaries of multi-valued RDNs.

Returns

• Pointer to the first attribute-value pair of the next RDN in sequence, or NULL if end is reached.

mbedtls_x509_serial_gets#

int mbedtls_x509_serial_gets (char *buf, size_t size, const mbedtls_x509_buf *serial)

Store the certificate serial in printable form into buf; no more than size characters will be written.

Returns

• The length of the string written (not including the terminated nul byte), or a negative error code.

mbedtls_x509_time_cmp#

int mbedtls_x509_time_cmp (const mbedtls_x509_time *t1, const mbedtls_x509_time *t2)

Compare pair of mbedtls_x509_time.

Returns

• < 0 if t1 is before t2 0 if t1 equals t2 > 0 if t1 is after t2

mbedtls_x509_time_is_past#

int mbedtls_x509_time_is_past (const mbedtls_x509_time *to)

Check a given mbedtls_x509_time against the system time and tell if it's in the past.

Note

• Intended usage is "if( is_past( valid_to ) ) ERROR". Hence the return value of 1 if on internal errors.

Returns

• 1 if the given time is in the past or an error occurred, 0 otherwise.

mbedtls_x509_time_is_future#

int mbedtls_x509_time_is_future (const mbedtls_x509_time *from)

Check a given mbedtls_x509_time against the system time and tell if it's in the future.

Note

• Intended usage is "if( is_future( valid_from ) ) ERROR". Hence the return value of 1 if on internal errors.

Returns

• 1 if the given time is in the future or an error occurred, 0 otherwise.

mbedtls_x509_parse_subject_alt_name#

int mbedtls_x509_parse_subject_alt_name (const mbedtls_x509_buf *san_buf, mbedtls_x509_subject_alternative_name *san)

This function parses an item in the SubjectAlternativeNames extension.

Please note that this function might allocate additional memory for a subject alternative name, thus mbedtls_x509_free_subject_alt_name has to be called to dispose of this additional memory afterwards.

Note

• Supported GeneralName types, as defined in RFC 5280: "rfc822Name", "dnsName", "directoryName", "uniformResourceIdentifier" and "hardware_module_name" of type "otherName", as defined in RFC 4108.

• This function should be called on a single raw data of subject alternative name. For example, after successful certificate parsing, one must iterate on every item in the crt->subject_alt_names sequence, and pass it to this function.

Warnings

• The target structure contains pointers to the raw data of the parsed certificate, and its lifetime is restricted by the lifetime of the certificate.

Returns

• 0 on success

• MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE for an unsupported SAN type.

• Another negative value for any other failure.

mbedtls_x509_free_subject_alt_name#

void mbedtls_x509_free_subject_alt_name (mbedtls_x509_subject_alternative_name *san)

Unallocate all data related to subject alternative name.

mbedtls_x509write_crt_init#

void mbedtls_x509write_crt_init (mbedtls_x509write_cert *ctx)

Initialize a CRT writing context.

mbedtls_x509write_crt_set_version#

void mbedtls_x509write_crt_set_version (mbedtls_x509write_cert *ctx, int version)

Set the version for a Certificate Default: MBEDTLS_X509_CRT_VERSION_3.

mbedtls_x509write_crt_set_serial#

int MBEDTLS_DEPRECATED mbedtls_x509write_crt_set_serial (mbedtls_x509write_cert *ctx, const mbedtls_mpi *serial)

Set the serial number for a Certificate.

Note

• Even though the MBEDTLS_BIGNUM_C guard looks redundant since X509 depends on PK and PK depends on BIGNUM, this emphasizes a direct dependency between X509 and BIGNUM which is going to be deprecated in the future.

Returns

• 0 if successful

mbedtls_x509write_crt_set_serial_raw#

int mbedtls_x509write_crt_set_serial_raw (mbedtls_x509write_cert *ctx, unsigned char *serial, size_t serial_len)

Set the serial number for a Certificate.

Returns

• 0 if successful, or MBEDTLS_ERR_X509_BAD_INPUT_DATA if the provided input buffer is too big (longer than MBEDTLS_X509_RFC5280_MAX_SERIAL_LEN)

mbedtls_x509write_crt_set_validity#

int mbedtls_x509write_crt_set_validity (mbedtls_x509write_cert *ctx, const char *not_before, const char *not_after)

Set the validity period for a Certificate Timestamps should be in string format for UTC timezone i.e.

"YYYYMMDDhhmmss" e.g. "20131231235959" for December 31st 2013 at 23:59:59

Returns

• 0 if timestamp was parsed successfully, or a specific error code

mbedtls_x509write_crt_set_issuer_name#

int mbedtls_x509write_crt_set_issuer_name (mbedtls_x509write_cert *ctx, const char *issuer_name)

Set the issuer name for a Certificate Issuer names should contain a comma-separated list of OID types and values: e.g.

"C=UK,O=ARM,CN=Mbed TLS CA"

Returns

• 0 if issuer name was parsed successfully, or a specific error code

mbedtls_x509write_crt_set_subject_name#

int mbedtls_x509write_crt_set_subject_name (mbedtls_x509write_cert *ctx, const char *subject_name)

Set the subject name for a Certificate Subject names should contain a comma-separated list of OID types and values: e.g.

"C=UK,O=ARM,CN=Mbed TLS Server 1"

Returns

• 0 if subject name was parsed successfully, or a specific error code

mbedtls_x509write_crt_set_subject_key#

void mbedtls_x509write_crt_set_subject_key (mbedtls_x509write_cert *ctx, mbedtls_pk_context *key)

Set the subject public key for the certificate.

mbedtls_x509write_crt_set_issuer_key#

void mbedtls_x509write_crt_set_issuer_key (mbedtls_x509write_cert *ctx, mbedtls_pk_context *key)

Set the issuer key used for signing the certificate.

mbedtls_x509write_crt_set_md_alg#

void mbedtls_x509write_crt_set_md_alg (mbedtls_x509write_cert *ctx, mbedtls_md_type_t md_alg)

Set the MD algorithm to use for the signature (e.g.

MBEDTLS_MD_SHA1)

mbedtls_x509write_crt_set_extension#

int mbedtls_x509write_crt_set_extension (mbedtls_x509write_cert *ctx, const char *oid, size_t oid_len, int critical, const unsigned char *val, size_t val_len)

Generic function to add to or replace an extension in the CRT.

Returns

• 0 if successful, or a MBEDTLS_ERR_X509_ALLOC_FAILED

mbedtls_x509write_crt_set_basic_constraints#

int mbedtls_x509write_crt_set_basic_constraints (mbedtls_x509write_cert *ctx, int is_ca, int max_pathlen)

Set the basicConstraints extension for a CRT.

Returns

• 0 if successful, or a MBEDTLS_ERR_X509_ALLOC_FAILED

mbedtls_x509write_crt_set_key_usage#

int mbedtls_x509write_crt_set_key_usage (mbedtls_x509write_cert *ctx, unsigned int key_usage)

Set the Key Usage Extension flags (e.g.

MBEDTLS_X509_KU_DIGITAL_SIGNATURE | MBEDTLS_X509_KU_KEY_CERT_SIGN)

Returns

• 0 if successful, or MBEDTLS_ERR_X509_ALLOC_FAILED

mbedtls_x509write_crt_set_ext_key_usage#

int mbedtls_x509write_crt_set_ext_key_usage (mbedtls_x509write_cert *ctx, const mbedtls_asn1_sequence *exts)

Set the Extended Key Usage Extension (e.g.

MBEDTLS_OID_SERVER_AUTH)

Returns

• 0 if successful, or MBEDTLS_ERR_X509_ALLOC_FAILED

mbedtls_x509write_crt_set_ns_cert_type#

int mbedtls_x509write_crt_set_ns_cert_type (mbedtls_x509write_cert *ctx, unsigned char ns_cert_type)

Set the Netscape Cert Type flags (e.g.

MBEDTLS_X509_NS_CERT_TYPE_SSL_CLIENT | MBEDTLS_X509_NS_CERT_TYPE_EMAIL)

Returns

• 0 if successful, or MBEDTLS_ERR_X509_ALLOC_FAILED

mbedtls_x509write_crt_free#

void mbedtls_x509write_crt_free (mbedtls_x509write_cert *ctx)

Free the contents of a CRT write context.

mbedtls_x509write_crt_der#

int mbedtls_x509write_crt_der (mbedtls_x509write_cert *ctx, unsigned char *buf, size_t size, int(*f_rng)(void *, unsigned char *, size_t), void *p_rng)

Write a built up certificate to a X509 DER structure Note: data is written at the end of the buffer! Use the return value to determine where you should start using the buffer.

Returns

• length of data written if successful, or a specific error code

Note

• f_rng is used for the signature operation.

mbedtls_x509write_crt_pem#

int mbedtls_x509write_crt_pem (mbedtls_x509write_cert *ctx, unsigned char *buf, size_t size, int(*f_rng)(void *, unsigned char *, size_t), void *p_rng)

Write a built up certificate to a X509 PEM string.

Returns

• 0 if successful, or a specific error code

Note

• f_rng is used for the signature operation.

MBEDTLS_X509_MAX_INTERMEDIATE_CA#

#define MBEDTLS_X509_MAX_INTERMEDIATE_CA

8

Maximum number of intermediate CAs in a verification chain.

That is, maximum length of the chain, excluding the end-entity certificate and the trusted root certificate.

Set this to a low value to prevent an adversary from making you waste resources verifying an overlong certificate chain.