File syn_x509.h¶

FileList > crypto > syn_x509.h

Zero-Heap X.509 v3 Certificate & Chain Parser and Validator.

#include "syntropic/crypto/syn_asn1.h"
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>

Classes¶

Type	Name
struct	SYN_X509_Cert

Public Types¶

Type	Name
enum	SYN_X509_Algo

Public Functions¶

Type	Name
bool	syn_x509_parse (const uint8_t * der, size_t der_len, SYN_X509_Cert * cert_out) Parse a raw DER-encoded X.509 certificate.
bool	syn_x509_validate_chain (const SYN_X509_Cert * cert, const SYN_X509_Cert * root_ca, const char * expected_cn) Validate a certificate chain back to a trusted Root CA certificate.
bool	syn_x509_verify_signature (const SYN_X509_Cert * cert, const uint8_t * issuer_pubkey, size_t issuer_pubkey_len, SYN_X509_Algo algo) Verify certificate signature against an issuer's public key.

Macros¶

Type	Name
define	SYN_X509_MAX_NAME_LEN `128U` Maximum CommonName string length (128).
define	SYN_X509_PUBKEY_MAX_LEN `128U` Maximum public key buffer length (128).
define	SYN_X509_SIG_MAX_LEN `256U` Maximum signature buffer length (256).

Public Types Documentation¶

enum SYN_X509_Algo¶

enum SYN_X509_Algo {
    SYN_X509_ALGO_UNKNOWN = 0,
    SYN_X509_ALGO_ED25519,
    SYN_X509_ALGO_ECDSA_P256,
    SYN_X509_ALGO_RSA_PSS
};

Public Key Algorithm Types in X.509 SubjectPublicKeyInfo

Public Functions Documentation¶

function syn_x509_parse¶

Parse a raw DER-encoded X.509 certificate.

bool syn_x509_parse (
    const uint8_t * der,
    size_t der_len,
    SYN_X509_Cert * cert_out
)

Parameters:

der Raw DER bytes of certificate.
der_len Length of DER bytes.
cert_out [out] Output parsed certificate struct.

Returns:

true if valid X.509 certificate parsed successfully.

function syn_x509_validate_chain¶

Validate a certificate chain back to a trusted Root CA certificate.

bool syn_x509_validate_chain (
    const SYN_X509_Cert * cert,
    const SYN_X509_Cert * root_ca,
    const char * expected_cn
)

Parameters:

cert Leaf certificate.
root_ca Trusted Root CA certificate.
expected_cn Expected Server Name (SNI) to match against leaf CN/SAN.

Returns:

true if chain is valid and trusted.

function syn_x509_verify_signature¶

Verify certificate signature against an issuer's public key.

bool syn_x509_verify_signature (
    const SYN_X509_Cert * cert,
    const uint8_t * issuer_pubkey,
    size_t issuer_pubkey_len,
    SYN_X509_Algo algo
)

Parameters:

cert Parsed child certificate to verify.
issuer_pubkey Issuer's public key.
issuer_pubkey_len Issuer's public key length.
algo Algorithm of issuer's public key.

Returns:

true if signature is valid.

Macro Definition Documentation¶

define SYN_X509_MAX_NAME_LEN¶

Maximum CommonName string length (128).

#define SYN_X509_MAX_NAME_LEN `128U`

define SYN_X509_PUBKEY_MAX_LEN¶

Maximum public key buffer length (128).

#define SYN_X509_PUBKEY_MAX_LEN `128U`

define SYN_X509_SIG_MAX_LEN¶

Maximum signature buffer length (256).

#define SYN_X509_SIG_MAX_LEN `256U`

The documentation for this class was generated from the following file src/syntropic/crypto/syn_x509.h