--tls.h v1.58
local ffi = require'ffi'
ffi.cdef[[
typedef size_t time_t;

enum {
	TLS_PROTOCOL_TLSv1_0 = (1 << 1),
	TLS_PROTOCOL_TLSv1_1 = (1 << 2),
	TLS_PROTOCOL_TLSv1_2 = (1 << 3),
	TLS_PROTOCOL_TLSv1_3 = (1 << 4),

	TLS_WANT_POLLIN   = -2,
	TLS_WANT_POLLOUT  = -3,

	/* RFC 6960 Section 2.3 */
	TLS_OCSP_RESPONSE_SUCCESSFUL     = 0,
	TLS_OCSP_RESPONSE_MALFORMED      = 1,
	TLS_OCSP_RESPONSE_INTERNALERROR  = 2,
	TLS_OCSP_RESPONSE_TRYLATER       = 3,
	TLS_OCSP_RESPONSE_SIGREQUIRED    = 4,
	TLS_OCSP_RESPONSE_UNAUTHORIZED   = 5,

	/* RFC 6960 Section 2.2 */
	TLS_OCSP_CERT_GOOD     = 0,
	TLS_OCSP_CERT_REVOKED  = 1,
	TLS_OCSP_CERT_UNKNOWN  = 2,

	/* RFC 5280 Section 5.3.1 */
	TLS_CRL_REASON_UNSPECIFIED             = 0,
	TLS_CRL_REASON_KEY_COMPROMISE          = 1,
	TLS_CRL_REASON_CA_COMPROMISE           = 2,
	TLS_CRL_REASON_AFFILIATION_CHANGED     = 3,
	TLS_CRL_REASON_SUPERSEDED              = 4,
	TLS_CRL_REASON_CESSATION_OF_OPERATION  = 5,
	TLS_CRL_REASON_CERTIFICATE_HOLD        = 6,
	TLS_CRL_REASON_REMOVE_FROM_CRL         = 8,
	TLS_CRL_REASON_PRIVILEGE_WITHDRAWN     = 9,
	TLS_CRL_REASON_AA_COMPROMISE           = 10,

	TLS_MAX_SESSION_ID_LENGTH              = 32,
	TLS_TICKET_KEY_SIZE                    = 48,
};

struct tls;
struct tls_config;

typedef ssize_t (*tls_read_cb )(struct tls *_ctx, char *_buf, size_t _buflen, void *_cb_arg);
typedef ssize_t (*tls_write_cb)(struct tls *_ctx, char *_buf, size_t _buflen, void *_cb_arg);

int tls_init(void);

const char *tls_config_error(struct tls_config *_config);
const char *tls_error(struct tls *_ctx);

struct tls_config *tls_config_new(void);
void tls_config_free(struct tls_config *_config);

const char *tls_default_ca_cert_file(void);

int tls_config_add_keypair_file(struct tls_config *_config,
    const char *_cert_file, const char *_key_file);
int tls_config_add_keypair_mem(struct tls_config *_config, const uint8_t *_cert,
    size_t _cert_len, const uint8_t *_key, size_t _key_len);
int tls_config_add_keypair_ocsp_file(struct tls_config *_config,
    const char *_cert_file, const char *_key_file,
    const char *_ocsp_staple_file);
int tls_config_add_keypair_ocsp_mem(struct tls_config *_config, const uint8_t *_cert,
    size_t _cert_len, const uint8_t *_key, size_t _key_len,
    const uint8_t *_staple, size_t _staple_len);
int tls_config_set_alpn(struct tls_config *_config, const char *_alpn);
int tls_config_set_ca_file(struct tls_config *_config, const char *_ca_file);
int tls_config_set_ca_path(struct tls_config *_config, const char *_ca_path);
int tls_config_set_ca_mem(struct tls_config *_config, const uint8_t *_ca,
    size_t _len);
int tls_config_set_cert_file(struct tls_config *_config,
    const char *_cert_file);
int tls_config_set_cert_mem(struct tls_config *_config, const uint8_t *_cert,
    size_t _len);
int tls_config_set_ciphers(struct tls_config *_config, const char *_ciphers);
int tls_config_set_crl_file(struct tls_config *_config, const char *_crl_file);
int tls_config_set_crl_mem(struct tls_config *_config, const uint8_t *_crl,
    size_t _len);
int tls_config_set_dheparams(struct tls_config *_config, const char *_params);
int tls_config_set_ecdhecurve(struct tls_config *_config, const char *_curve);
int tls_config_set_ecdhecurves(struct tls_config *_config, const char *_curves);
int tls_config_set_key_file(struct tls_config *_config, const char *_key_file);
int tls_config_set_key_mem(struct tls_config *_config, const uint8_t *_key,
    size_t _len);
int tls_config_set_keypair_file(struct tls_config *_config,
    const char *_cert_file, const char *_key_file);
int tls_config_set_keypair_mem(struct tls_config *_config, const uint8_t *_cert,
    size_t _cert_len, const uint8_t *_key, size_t _key_len);
int tls_config_set_keypair_ocsp_file(struct tls_config *_config,
    const char *_cert_file, const char *_key_file, const char *_staple_file);
int tls_config_set_keypair_ocsp_mem(struct tls_config *_config, const uint8_t *_cert,
    size_t _cert_len, const uint8_t *_key, size_t _key_len,
    const uint8_t *_staple, size_t staple_len);
int tls_config_set_ocsp_staple_mem(struct tls_config *_config,
    const uint8_t *_staple, size_t _len);
int tls_config_set_ocsp_staple_file(struct tls_config *_config,
    const char *_staple_file);
int tls_config_set_protocols(struct tls_config *_config, uint32_t _protocols);
int tls_config_set_session_fd(struct tls_config *_config, int _session_fd);
int tls_config_set_verify_depth(struct tls_config *_config, int _verify_depth);

void tls_config_prefer_ciphers_client(struct tls_config *_config);
void tls_config_prefer_ciphers_server(struct tls_config *_config);

void tls_config_insecure_noverifycert(struct tls_config *_config);
void tls_config_insecure_noverifyname(struct tls_config *_config);
void tls_config_insecure_noverifytime(struct tls_config *_config);
void tls_config_verify(struct tls_config *_config);

void tls_config_ocsp_require_stapling(struct tls_config *_config);
void tls_config_verify_client(struct tls_config *_config);
void tls_config_verify_client_optional(struct tls_config *_config);

void tls_config_clear_keys(struct tls_config *_config);
int tls_config_parse_protocols(uint32_t *_protocols, const char *_protostr);

int tls_config_set_session_id(struct tls_config *_config,
    const unsigned char *_session_id, size_t _len);
int tls_config_set_session_lifetime(struct tls_config *_config, int _lifetime);
int tls_config_add_ticket_key(struct tls_config *_config, uint32_t _keyrev,
    unsigned char *_key, size_t _keylen);

struct tls *tls_client(void);
struct tls *tls_server(void);
int tls_configure(struct tls *_ctx, struct tls_config *_config);
void tls_reset(struct tls *_ctx);
void tls_free(struct tls *_ctx);

int tls_accept_fds(struct tls *_ctx, struct tls **_cctx, int _fd_read,
    int _fd_write);
int tls_accept_socket(struct tls *_ctx, struct tls **_cctx, int _socket);
int tls_accept_cbs(struct tls *_ctx, struct tls **_cctx,
    tls_read_cb _read_cb, tls_write_cb _write_cb, void *_cb_arg);
int tls_connect(struct tls *_ctx, const char *_host, const char *_port);
int tls_connect_fds(struct tls *_ctx, int _fd_read, int _fd_write,
    const char *_servername);
int tls_connect_servername(struct tls *_ctx, const char *_host,
    const char *_port, const char *_servername);
int tls_connect_socket(struct tls *_ctx, int _s, const char *_servername);
int tls_connect_cbs(struct tls *_ctx, tls_read_cb _read_cb,
    tls_write_cb _write_cb, void *_cb_arg, const char *_servername);
int tls_handshake(struct tls *_ctx);
ssize_t tls_read(struct tls *_ctx, void *_buf, size_t _buflen);
ssize_t tls_write(struct tls *_ctx, const void *_buf, size_t _buflen);
int tls_close(struct tls *_ctx);

int tls_peer_cert_provided(struct tls *_ctx);
int tls_peer_cert_contains_name(struct tls *_ctx, const char *_name);

const char *tls_peer_cert_hash(struct tls *_ctx);
const char *tls_peer_cert_issuer(struct tls *_ctx);
const char *tls_peer_cert_subject(struct tls *_ctx);
time_t tls_peer_cert_notbefore(struct tls *_ctx);
time_t tls_peer_cert_notafter(struct tls *_ctx);
const uint8_t *tls_peer_cert_chain_pem(struct tls *_ctx, size_t *_len);

const char *tls_conn_alpn_selected(struct tls *_ctx);
const char *tls_conn_cipher(struct tls *_ctx);
int tls_conn_cipher_strength(struct tls *_ctx);
const char *tls_conn_servername(struct tls *_ctx);
int tls_conn_session_resumed(struct tls *_ctx);
const char *tls_conn_version(struct tls *_ctx);

uint8_t *tls_load_file(const char *_file, size_t *_len, char *_password);
void tls_unload_file(uint8_t *_buf, size_t len);

int tls_ocsp_process_response(struct tls *_ctx, const unsigned char *_response,
    size_t _size);
int tls_peer_ocsp_cert_status(struct tls *_ctx);
int tls_peer_ocsp_crl_reason(struct tls *_ctx);
time_t tls_peer_ocsp_next_update(struct tls *_ctx);
int tls_peer_ocsp_response_status(struct tls *_ctx);
const char *tls_peer_ocsp_result(struct tls *_ctx);
time_t tls_peer_ocsp_revocation_time(struct tls *_ctx);
time_t tls_peer_ocsp_this_update(struct tls *_ctx);
const char *tls_peer_ocsp_url(struct tls *_ctx);
]]
