# Module Nettls_gnutls_bindings

    module Nettls_gnutls_bindings: sig .. end

Bindings of a C library

    type gnutls_cipher_algorithm_t

    type gnutls_kx_algorithm_t

    type gnutls_mac_algorithm_t

    type gnutls_compression_method_t

    type gnutls_pk_algorithm_t

    type gnutls_sign_algorithm_t

    type gnutls_certificate_type_t

    type gnutls_digest_algorithm_t = gnutls_mac_algorithm_t

    type gnutls_session_t

    type gnutls_dh_params_t

    type gnutls_priority_t

    type gnutls_cipher_hd_t

    type gnutls_x509_privkey_t

    type gnutls_x509_crl_t

    type gnutls_x509_crt_t

    type gnutls_openpgp_keyring_t

    type gnutls_certificate_credentials_t

    type gnutls_anon_server_credentials_t

    type gnutls_anon_client_credentials_t

    type gnutls_srp_server_credentials_t

    type gnutls_srp_client_credentials_t

    type gnutls_psk_server_credentials_t

    type gnutls_psk_client_credentials_t

    type gnutls_params_type_t = [ `Dh | `Ecdh | `Rsa_export ]

    type gnutls_credentials_type_t = [ `Anon | `Certificate | `Ia | `Psk | `Srp ]

    type gnutls_alert_level_t = [ `Fatal | `Warning ]

    type gnutls_alert_description_t = [ `Access_denied
           | `Bad_certificate
           | `Bad_record_mac
           | `Certificate_expired
           | `Certificate_revoked
           | `Certificate_unknown
           | `Certificate_unobtainable
           | `Close_notify
           | `Decode_error
           | `Decompression_failure
           | `Decrypt_error
           | `Decryption_failed
           | `Export_restriction
           | `Handshake_failure
           | `Illegal_parameter
           | `Inner_application_failure
           | `Inner_application_verification
           | `Insufficient_security
           | `Internal_error
           | `No_renegotiation
           | `Protocol_version
           | `Record_overflow
           | `Ssl3_no_certificate
           | `Unexpected_message
           | `Unknown_ca
           | `Unknown_psk_identity
           | `Unrecognized_name
           | `Unsupported_certificate
           | `Unsupported_extension
           | `User_canceled ]

    type gnutls_handshake_description_t = [ `Certificate_pkt
           | `Certificate_request
           | `Certificate_verify
           | `Change_cipher_spec
           | `Client_hello
           | `Client_hello_v2
           | `Client_key_exchange
           | `Finished
           | `Hello_request
           | `Hello_verify_request
           | `New_session_ticket
           | `Server_hello
           | `Server_hello_done
           | `Server_key_exchange
           | `Supplemental ]

    type gnutls_certificate_status_t_flag = [ `Expired
           | `Insecure_algorithm
           | `Invalid
           | `Not_activated
           | `Revoked
           | `Signer_not_ca
           | `Signer_not_found ]

    type gnutls_certificate_status_t = gnutls_certificate_status_t_flag list

    type gnutls_certificate_request_t = [ `Ignore | `Request | `Require ]

    type gnutls_certificate_verify_flags_flag = [ `Allow_any_x509_v1_ca_crt
           | `Allow_sign_rsa_md2
           | `Allow_sign_rsa_md5
           | `Allow_x509_v1_ca_crt
           | `Disable_ca_sign
           | `Disable_crl_checks
           | `Disable_time_checks
           | `Disable_trusted_time_checks
           | `Do_not_allow_same
           | `Do_not_allow_x509_v1_ca_crt ]

    type gnutls_certificate_verify_flags = gnutls_certificate_verify_flags_flag list

    type gnutls_openpgp_crt_status_t = [ `Cert | `Cert_fingerprint ]

    type gnutls_close_request_t = [ `Rdwr | `Wr ]

    type gnutls_protocol_t = [ `Dtls1_0 | `Ssl3 | `Tls1_0 | `Tls1_1 | `Tls1_2 | `Version_unknown ]

    type gnutls_x509_crt_fmt_t = [ `Der | `Pem ]

    type gnutls_certificate_print_formats_t = [ `Full | `Oneline | `Unsigned_full ]

    type gnutls_ecc_curve_t = [ `Invalid | `Secp192r1 | `Secp224r1 | `Secp256r1 | `Secp384r1 | `Secp521r1 ]

    type gnutls_sec_param_t = [ `High | `Low | `Normal | `Ultra | `Unknown | `Weak ]

    type gnutls_init_flags_flag = [ `Client | `Datagram | `Nonblock | `Server ]

    type gnutls_init_flags = gnutls_init_flags_flag list

    type gnutls_server_name_type_t = [ `Dns ]

    type gnutls_supplemental_data_format_type_t = [ `User_mapping_data ]

    type gnutls_psk_key_flags = [ `Hex | `Raw ]

    type gnutls_x509_subject_alt_name_t = [ `Dn
           | `Dnsname
           | `Ipaddress
           | `Othername
           | `Othername_xmpp
           | `Rfc822name
           | `Uri ]

    type gnutls_privkey_type_t = [ `Ext | `Openpgp | `Pkcs11 | `X509 ]

    type key_usage_flag = [ `Crl_sign
           | `Data_encipherment
           | `Decipher_only
           | `Digital_signature
           | `Encipher_only
           | `Key_agreement
           | `Key_cert_sign
           | `Key_encipherment
           | `Non_repudiation ]

    type key_usage = key_usage_flag list

    type gnutls_channel_binding_t = [ `Tls_unique ]

    type gnutls_info_access_what_t = [ `Accesslocation_generalname_type
           | `Accessmethod_oid
           | `Caissuers_uri
           | `Ocsp_uri
           | `Uri ]

    type gnutls_certificate_import_flags_flag = [ `Fail_if_unsorted | `Import_fail_if_exceed ]

    type gnutls_certificate_import_flags = gnutls_certificate_import_flags_flag list

    type error_code = [ `Again
           | `Asn1_der_error
           | `Asn1_der_overflow
           | `Asn1_element_not_found
           | `Asn1_generic_error
           | `Asn1_identifier_not_found
           | `Asn1_syntax_error
           | `Asn1_tag_error
           | `Asn1_tag_implicit
           | `Asn1_type_any_error
           | `Asn1_value_not_found
           | `Asn1_value_not_valid
           | `Bad_cookie
           | `Base64_decoding_error
           | `Base64_encoding_error
           | `Base64_unexpected_header_error
           | `Certificate_error
           | `Certificate_key_mismatch
           | `Certificate_list_unsorted
           | `Channel_binding_not_available
           | `Compression_failed
           | `Constraint_error
           | `Crypto_already_registered
           | `Crypto_init_failed
           | `Cryptodev_device_error
           | `Cryptodev_ioctl_error
           | `Db_error
           | `Decompression_failed
           | `Decryption_failed
           | `Dh_prime_unacceptable
           | `Ecc_no_supported_curves
           | `Ecc_unsupported_curve
           | `Encryption_failed
           | `Error_in_finished_packet
           | `Expired
           | `Fatal_alert_received
           | `File_error
           | `Got_application_data
           | `Handshake_too_large
           | `Hash_failed
           | `Ia_verify_failed
           | `Illegal_parameter
           | `Illegal_srp_username
           | `Incompat_dsa_key_with_tls_protocol
           | `Incompatible_crypto_library
           | `Incompatible_libtasn1_library
           | `Insufficient_credentials
           | `Internal_error
           | `Interrupted
           | `Invalid_password
           | `Invalid_request
           | `Invalid_session
           | `Key_usage_violation
           | `Large_packet
           | `Locking_error
           | `Mac_verify_failed
           | `Memory_error
           | `Mpi_print_failed
           | `Mpi_scan_failed
           | `No_certificate_found
           | `No_cipher_suites
           | `No_compression_algorithms
           | `No_temporary_dh_params
           | `No_temporary_rsa_params
           | `Openpgp_fingerprint_unsupported
           | `Openpgp_getkey_failed
           | `Openpgp_keyring_error
           | `Openpgp_preferred_key_error
           | `Openpgp_subkey_error
           | `Openpgp_uid_revoked
           | `Parsing_error
           | `Pk_decryption_failed
           | `Pk_encryption_failed
           | `Pk_sig_verify_failed
           | `Pk_sign_failed
           | `Pkcs11_attribute_error
           | `Pkcs11_data_error
           | `Pkcs11_device_error
           | `Pkcs11_error
           | `Pkcs11_key_error
           | `Pkcs11_load_error
           | `Pkcs11_pin_error
           | `Pkcs11_pin_expired
           | `Pkcs11_pin_locked
           | `Pkcs11_requested_object_not_availble
           | `Pkcs11_session_error
           | `Pkcs11_signature_error
           | `Pkcs11_slot_error
           | `Pkcs11_token_error
           | `Pkcs11_unsupported_feature_error
           | `Pkcs11_user_error
           | `Pkcs1_wrong_pad
           | `Premature_termination
           | `Pull_error
           | `Push_error
           | `Random_failed
           | `Received_illegal_extension
           | `Received_illegal_parameter
           | `Record_limit_reached
           | `Rehandshake
           | `Requested_data_not_available
           | `Safe_renegotiation_failed
           | `Short_memory_buffer
           | `Srp_pwd_error
           | `Srp_pwd_parsing_error
           | `Success
           | `Timedout
           | `Too_many_empty_packets
           | `Too_many_handshake_packets
           | `Unexpected_handshake_packet
           | `Unexpected_packet
           | `Unexpected_packet_length
           | `Unimplemented_feature
           | `Unknown_algorithm
           | `Unknown_cipher_suite
           | `Unknown_cipher_type
           | `Unknown_compression_algorithm
           | `Unknown_hash_algorithm
           | `Unknown_pk_algorithm
           | `Unknown_pkcs_bag_type
           | `Unknown_pkcs_content_type
           | `Unknown_srp_username
           | `Unsafe_renegotiation_denied
           | `Unsupported_certificate_type
           | `Unsupported_signature_algorithm
           | `Unsupported_version_packet
           | `Unwanted_algorithm
           | `User_error
           | `Warning_alert_received
           | `Warning_ia_fphf_received
           | `Warning_ia_iphf_received
           | `X509_unknown_san
           | `X509_unsupported_attribute
           | `X509_unsupported_critical_extension
           | `X509_unsupported_oid ]

    type gnutls_pkcs_encrypt_flags_t_flag = [ `Plain
           | `Use_pbes2_3des
           | `Use_pkcs12_3des
           | `Use_pkcs12_arcfour
           | `Use_pkcs12_rc2_40 ]

    type gnutls_pkcs_encrypt_flags_t = gnutls_pkcs_encrypt_flags_t_flag list

    type empty_flags_flag = [ `Dummy ]

    type empty_flags = empty_flags_flag list

    type str_datum = string

    type str_datum_p = string

    type const_str_datum_p = string

    val gnutls_global_init : unit -> unit

    val gnutls_error_is_fatal : error_code -> bool

    val gnutls_strerror : error_code -> string

    val gnutls_strerror_name : error_code -> string

    val gnutls_check_version : unit -> string

    val gnutls_global_set_log_level : int -> unit

    val gnutls_init : gnutls_init_flags ->
           gnutls_session_t

    val gnutls_certificate_server_set_request : gnutls_session_t ->
           gnutls_certificate_request_t -> unit

    val gnutls_certificate_send_x509_rdn_sequence : gnutls_session_t -> bool -> unit

    val gnutls_certificate_verify_peers2 : gnutls_session_t ->
           gnutls_certificate_status_t

    val gnutls_certificate_get_peers : gnutls_session_t -> string array

    val gnutls_record_get_direction : gnutls_session_t -> bool

    val gnutls_handshake : gnutls_session_t -> unit

    val gnutls_rehandshake : gnutls_session_t -> unit

    val gnutls_record_send : gnutls_session_t -> Netsys_mem.memory -> int -> int

    val gnutls_record_recv : gnutls_session_t -> Netsys_mem.memory -> int

    val gnutls_record_check_pending : gnutls_session_t -> int

    val gnutls_bye : gnutls_session_t ->
           gnutls_close_request_t -> unit

    val gnutls_alert_get : gnutls_session_t ->
           gnutls_alert_description_t

    val gnutls_alert_get_name : gnutls_alert_description_t -> string

    val gnutls_alert_get_strname : gnutls_alert_description_t -> string

    val gnutls_alert_send : gnutls_session_t ->
           gnutls_alert_level_t ->
           gnutls_alert_description_t -> unit

    val gnutls_alert_send_appropriate : gnutls_session_t -> int -> unit

    val gnutls_error_to_alert : error_code ->
           gnutls_alert_description_t *
           gnutls_alert_level_t

    val gnutls_priority_init : string -> gnutls_priority_t

    val gnutls_priority_get_cipher_suite_index : gnutls_priority_t -> int -> int

    val gnutls_priority_set : gnutls_session_t ->
           gnutls_priority_t -> unit

    val gnutls_set_default_priority : gnutls_session_t -> unit

    val gnutls_sec_param_to_pk_bits : gnutls_pk_algorithm_t ->
           gnutls_sec_param_t -> int

    val gnutls_pk_bits_to_sec_param : gnutls_pk_algorithm_t ->
           int -> gnutls_sec_param_t

    val gnutls_sec_param_get_name : gnutls_sec_param_t -> string

    val gnutls_session_set_data : gnutls_session_t -> string -> unit

    val gnutls_session_get_data : gnutls_session_t -> string

    val gnutls_session_get_id : gnutls_session_t -> string

    val gnutls_session_is_resumed : gnutls_session_t -> bool

    val gnutls_db_set_cache_expiration : gnutls_session_t -> int -> unit

    val gnutls_db_remove_session : gnutls_session_t -> unit

    val gnutls_db_check_entry : gnutls_session_t -> string -> int

    val gnutls_session_ticket_key_generate : unit -> string

    val gnutls_session_ticket_enable_client : gnutls_session_t -> unit

    val gnutls_session_ticket_enable_server : gnutls_session_t ->
           str_datum_p -> unit

    val gnutls_prf : gnutls_session_t ->
           Netsys_mem.memory -> bool -> Netsys_mem.memory -> Netsys_mem.memory -> unit

    val gnutls_prf_raw : gnutls_session_t ->
           Netsys_mem.memory -> Netsys_mem.memory -> Netsys_mem.memory -> unit

    val gnutls_session_channel_binding : gnutls_session_t ->
           gnutls_channel_binding_t -> string

    val gnutls_ecc_curve_get_name : gnutls_ecc_curve_t -> string

    val gnutls_ecc_curve_get_size : gnutls_ecc_curve_t -> int

    val gnutls_ecc_curve_get : gnutls_session_t ->
           gnutls_ecc_curve_t

    val gnutls_cipher_get : gnutls_session_t ->
           gnutls_cipher_algorithm_t

    val gnutls_kx_get : gnutls_session_t ->
           gnutls_kx_algorithm_t

    val gnutls_mac_get : gnutls_session_t ->
           gnutls_mac_algorithm_t

    val gnutls_compression_get : gnutls_session_t ->
           gnutls_compression_method_t

    val gnutls_certificate_type_get : gnutls_session_t ->
           gnutls_certificate_type_t

    val gnutls_cipher_get_key_size : gnutls_cipher_algorithm_t -> int

    val gnutls_mac_get_key_size : gnutls_mac_algorithm_t -> int

    val gnutls_cipher_get_name : gnutls_cipher_algorithm_t -> string

    val gnutls_mac_get_name : gnutls_mac_algorithm_t -> string

    val gnutls_compression_get_name : gnutls_compression_method_t -> string

    val gnutls_kx_get_name : gnutls_kx_algorithm_t -> string

    val gnutls_certificate_type_get_name : gnutls_certificate_type_t -> string

    val gnutls_pk_get_name : gnutls_pk_algorithm_t -> string

    val gnutls_sign_get_name : gnutls_sign_algorithm_t -> string

    val gnutls_mac_get_id : string -> gnutls_mac_algorithm_t

    val gnutls_compression_get_id : string -> gnutls_compression_method_t

    val gnutls_cipher_get_id : string -> gnutls_cipher_algorithm_t

    val gnutls_kx_get_id : string -> gnutls_kx_algorithm_t

    val gnutls_protocol_get_id : string -> gnutls_protocol_t

    val gnutls_certificate_type_get_id : string -> gnutls_certificate_type_t

    val gnutls_pk_get_id : string -> gnutls_pk_algorithm_t

    val gnutls_sign_get_id : string -> gnutls_sign_algorithm_t

    val gnutls_cipher_list : unit -> gnutls_cipher_algorithm_t list

    val gnutls_mac_list : unit -> gnutls_mac_algorithm_t list

    val gnutls_compression_list : unit -> gnutls_compression_method_t list

    val gnutls_protocol_list : unit -> gnutls_protocol_t list

    val gnutls_certificate_type_list : unit -> gnutls_certificate_type_t list

    val gnutls_kx_list : unit -> gnutls_kx_algorithm_t list

    val gnutls_pk_list : unit -> gnutls_pk_algorithm_t list

    val gnutls_sign_list : unit -> gnutls_sign_algorithm_t list

    val gnutls_protocol_get_version : gnutls_session_t ->
           gnutls_protocol_t

    val gnutls_protocol_get_name : gnutls_protocol_t -> string

    val gnutls_cipher_suite_get_name : gnutls_kx_algorithm_t ->
           gnutls_cipher_algorithm_t ->
           gnutls_mac_algorithm_t -> string

    val net_have_crypto : unit -> bool

    val gnutls_cipher_init : gnutls_cipher_algorithm_t ->
           str_datum_p ->
           str_datum_p ->
           gnutls_cipher_hd_t

    val gnutls_cipher_encrypt2 : gnutls_cipher_hd_t ->
           Netsys_mem.memory -> Netsys_mem.memory -> unit

    val gnutls_cipher_decrypt2 : gnutls_cipher_hd_t ->
           Netsys_mem.memory -> Netsys_mem.memory -> unit

    val gnutls_cipher_add_auth : gnutls_cipher_hd_t -> string -> unit

    val gnutls_cipher_tag : gnutls_cipher_hd_t -> string -> unit

    val gnutls_handshake_set_private_extensions : gnutls_session_t -> bool -> unit

    val gnutls_handshake_get_last_out : gnutls_session_t ->
           gnutls_handshake_description_t

    val gnutls_handshake_get_last_in : gnutls_session_t ->
           gnutls_handshake_description_t

    val gnutls_handshake_set_max_packet_length : gnutls_session_t -> int -> unit

    val gnutls_sign_algorithm_get_requested : gnutls_session_t ->
           int -> gnutls_sign_algorithm_t

    val gnutls_session_enable_compatibility_mode : gnutls_session_t -> unit

    val gnutls_record_disable_padding : gnutls_session_t -> unit

    val gnutls_record_get_max_size : gnutls_session_t -> int

    val gnutls_record_set_max_size : gnutls_session_t -> int -> unit

    val gnutls_server_name_set : gnutls_session_t ->
           gnutls_server_name_type_t -> string -> unit

    val gnutls_server_name_get : gnutls_session_t ->
           int -> string * gnutls_server_name_type_t

    val gnutls_safe_renegotiation_status : gnutls_session_t -> bool

    val gnutls_supplemental_get_name : gnutls_supplemental_data_format_type_t -> string

    val gnutls_credentials_clear : gnutls_session_t -> unit

    val gnutls_key_generate : int -> string

    val gnutls_fingerprint : gnutls_digest_algorithm_t ->
           str_datum_p -> string

    val gnutls_certificate_allocate_credentials : unit -> gnutls_certificate_credentials_t

    val gnutls_certificate_set_x509_system_trust : gnutls_certificate_credentials_t -> unit

    val gnutls_certificate_set_x509_trust_file : gnutls_certificate_credentials_t ->
           string -> gnutls_x509_crt_fmt_t -> unit

    val gnutls_certificate_set_x509_trust_mem : gnutls_certificate_credentials_t ->
           str_datum_p ->
           gnutls_x509_crt_fmt_t -> unit

    val gnutls_certificate_set_x509_crl_file : gnutls_certificate_credentials_t ->
           string -> gnutls_x509_crt_fmt_t -> unit

    val gnutls_certificate_set_x509_crl_mem : gnutls_certificate_credentials_t ->
           str_datum_p ->
           gnutls_x509_crt_fmt_t -> unit

    val gnutls_certificate_set_x509_key_file : gnutls_certificate_credentials_t ->
           string -> string -> gnutls_x509_crt_fmt_t -> unit

    val gnutls_certificate_set_x509_key_mem : gnutls_certificate_credentials_t ->
           str_datum_p ->
           str_datum_p ->
           gnutls_x509_crt_fmt_t -> unit

    val gnutls_certificate_set_x509_simple_pkcs12_file : gnutls_certificate_credentials_t ->
           string -> gnutls_x509_crt_fmt_t -> string -> unit

    val gnutls_certificate_set_x509_simple_pkcs12_mem : gnutls_certificate_credentials_t ->
           str_datum_p ->
           gnutls_x509_crt_fmt_t -> string -> unit

    val gnutls_certificate_set_x509_key : gnutls_certificate_credentials_t ->
           gnutls_x509_crt_t array ->
           gnutls_x509_privkey_t -> unit

    val gnutls_certificate_set_x509_trust : gnutls_certificate_credentials_t ->
           gnutls_x509_crt_t array -> int

    val gnutls_certificate_set_x509_crl : gnutls_certificate_credentials_t ->
           gnutls_x509_crl_t array -> int

    val gnutls_anon_allocate_server_credentials : unit -> gnutls_anon_server_credentials_t

    val gnutls_anon_allocate_client_credentials : unit -> gnutls_anon_client_credentials_t

    val gnutls_dh_params_init : unit -> gnutls_dh_params_t

    val gnutls_dh_params_import_raw : gnutls_dh_params_t ->
           str_datum_p ->
           str_datum_p -> unit

    val gnutls_dh_params_import_pkcs3 : gnutls_dh_params_t ->
           str_datum_p ->
           gnutls_x509_crt_fmt_t -> unit

    val gnutls_dh_params_generate2 : gnutls_dh_params_t -> int -> unit

    val gnutls_dh_params_cpy : gnutls_dh_params_t ->
           gnutls_dh_params_t -> unit

    val gnutls_certificate_set_dh_params : gnutls_certificate_credentials_t ->
           gnutls_dh_params_t -> unit

    val gnutls_anon_set_server_dh_params : gnutls_anon_server_credentials_t ->
           gnutls_dh_params_t -> unit

    val gnutls_psk_set_server_dh_params : gnutls_psk_server_credentials_t ->
           gnutls_dh_params_t -> unit

    val gnutls_dh_set_prime_bits : gnutls_session_t -> int -> unit

    val gnutls_dh_get_secret_bits : gnutls_session_t -> int

    val gnutls_dh_get_peers_public_bits : gnutls_session_t -> int

    val gnutls_dh_get_prime_bits : gnutls_session_t -> int

    val gnutls_dh_get_group : gnutls_session_t -> string * string

    val gnutls_dh_get_pubkey : gnutls_session_t -> string

    val gnutls_auth_get_type : gnutls_session_t ->
           gnutls_credentials_type_t

    val gnutls_auth_server_get_type : gnutls_session_t ->
           gnutls_credentials_type_t

    val gnutls_auth_client_get_type : gnutls_session_t ->
           gnutls_credentials_type_t

    val gnutls_certificate_get_ours : gnutls_session_t ->
           const_str_datum_p

    val gnutls_certificate_activation_time_peers : gnutls_session_t -> float

    val gnutls_certificate_expiration_time_peers : gnutls_session_t -> float

    val gnutls_certificate_client_get_request_status : gnutls_session_t -> bool

    val gnutls_certificate_get_issuer : gnutls_certificate_credentials_t ->
           gnutls_x509_crt_t ->
           empty_flags ->
           gnutls_x509_crt_t

    val gnutls_certificate_set_verify_flags : gnutls_certificate_credentials_t ->
           gnutls_certificate_verify_flags -> unit

    val gnutls_certificate_set_verify_limits : gnutls_certificate_credentials_t -> int -> int -> unit

    val gnutls_openpgp_send_cert : gnutls_session_t ->
           gnutls_openpgp_crt_status_t -> unit

    val gnutls_srp_allocate_client_credentials : unit -> gnutls_srp_client_credentials_t

    val gnutls_srp_set_client_credentials : gnutls_srp_client_credentials_t ->
           string -> string -> unit

    val gnutls_srp_allocate_server_credentials : unit -> gnutls_srp_server_credentials_t

    val gnutls_srp_set_server_credentials_file : gnutls_srp_server_credentials_t ->
           string -> string -> unit

    val gnutls_srp_server_get_username : gnutls_session_t -> string

    val gnutls_srp_set_prime_bits : gnutls_session_t -> int -> unit

    val gnutls_srp_verifier : string ->
           string ->
           str_datum_p ->
           str_datum_p ->
           str_datum_p -> string

    val gnutls_psk_allocate_client_credentials : unit -> gnutls_psk_client_credentials_t

    val gnutls_psk_set_client_credentials : gnutls_psk_client_credentials_t ->
           string ->
           str_datum_p ->
           gnutls_psk_key_flags -> unit

    val gnutls_psk_allocate_server_credentials : unit -> gnutls_psk_server_credentials_t

    val gnutls_psk_set_server_credentials_file : gnutls_psk_server_credentials_t -> string -> unit

    val gnutls_psk_set_server_credentials_hint : gnutls_psk_server_credentials_t -> string -> unit

    val gnutls_psk_server_get_username : gnutls_session_t -> string

    val gnutls_psk_client_get_hint : gnutls_session_t -> string

    val gnutls_x509_crt_init : unit -> gnutls_x509_crt_t

    val gnutls_x509_crt_import : gnutls_x509_crt_t ->
           const_str_datum_p ->
           gnutls_x509_crt_fmt_t -> unit

    val gnutls_x509_crt_export : gnutls_x509_crt_t ->
           gnutls_x509_crt_fmt_t -> string

    val gnutls_x509_crt_get_issuer_dn : gnutls_x509_crt_t -> string

    val gnutls_x509_crt_get_issuer_dn_oid : gnutls_x509_crt_t -> int -> string

    val gnutls_x509_crt_get_dn : gnutls_x509_crt_t -> string

    val gnutls_x509_crt_get_dn_oid : gnutls_x509_crt_t -> int -> string

    val gnutls_x509_crt_check_hostname : gnutls_x509_crt_t -> string -> bool

    val gnutls_x509_crt_get_signature_algorithm : gnutls_x509_crt_t ->
           gnutls_sign_algorithm_t

    val gnutls_x509_crt_get_signature : gnutls_x509_crt_t -> string

    val gnutls_x509_crt_get_version : gnutls_x509_crt_t -> int

    val gnutls_x509_crt_get_key_id : gnutls_x509_crt_t ->
           empty_flags -> string

    val gnutls_x509_crt_get_authority_key_id : gnutls_x509_crt_t -> string * bool

    val gnutls_x509_crt_get_subject_key_id : gnutls_x509_crt_t -> string * bool

    val gnutls_x509_crt_get_subject_unique_id : gnutls_x509_crt_t -> string

    val gnutls_x509_crt_get_issuer_unique_id : gnutls_x509_crt_t -> string

    val gnutls_x509_crt_get_authority_info_access : gnutls_x509_crt_t ->
           int -> gnutls_info_access_what_t -> string * bool

    val gnutls_x509_crt_get_activation_time : gnutls_x509_crt_t -> float

    val gnutls_x509_crt_get_expiration_time : gnutls_x509_crt_t -> float

    val gnutls_x509_crt_get_serial : gnutls_x509_crt_t -> string

    val gnutls_x509_crt_get_pk_algorithm : gnutls_x509_crt_t ->
           gnutls_pk_algorithm_t * int

    val gnutls_x509_crt_get_pk_rsa_raw : gnutls_x509_crt_t -> string * string

    val gnutls_x509_crt_get_pk_dsa_raw : gnutls_x509_crt_t -> string * string * string * string

    val gnutls_x509_crt_get_subject_alt_name : gnutls_x509_crt_t ->
           int -> gnutls_x509_subject_alt_name_t * string * bool

    val gnutls_x509_crt_get_subject_alt_othername_oid : gnutls_x509_crt_t ->
           int -> gnutls_x509_subject_alt_name_t * string

    val gnutls_x509_crt_get_issuer_alt_name : gnutls_x509_crt_t ->
           int -> gnutls_x509_subject_alt_name_t * string * bool

    val gnutls_x509_crt_get_issuer_alt_othername_oid : gnutls_x509_crt_t ->
           int -> gnutls_x509_subject_alt_name_t * string

    val gnutls_x509_crt_get_ca_status : gnutls_x509_crt_t -> bool

    val gnutls_x509_crt_get_basic_constraints : gnutls_x509_crt_t -> bool * bool * int

    val gnutls_x509_crt_get_key_usage : gnutls_x509_crt_t ->
           key_usage * bool

    val gnutls_x509_crt_get_extension_oid : gnutls_x509_crt_t -> int -> string

    val gnutls_x509_crt_get_extension_info : gnutls_x509_crt_t -> int -> string * bool

    val gnutls_x509_crt_get_extension_data : gnutls_x509_crt_t -> int -> string

    val gnutls_x509_crt_check_issuer : gnutls_x509_crt_t ->
           gnutls_x509_crt_t -> bool

    val gnutls_x509_crt_list_verify : gnutls_x509_crt_t array ->
           gnutls_x509_crt_t array ->
           gnutls_x509_crl_t array ->
           gnutls_certificate_verify_flags ->
           gnutls_certificate_status_t

    val gnutls_x509_crt_verify : gnutls_x509_crt_t ->
           gnutls_x509_crt_t array ->
           gnutls_certificate_verify_flags ->
           gnutls_certificate_status_t

    val gnutls_x509_crl_verify : gnutls_x509_crl_t ->
           gnutls_x509_crt_t array ->
           gnutls_certificate_verify_flags ->
           gnutls_certificate_status_t

    val gnutls_x509_crt_check_revocation : gnutls_x509_crt_t ->
           gnutls_x509_crl_t array -> bool

    val gnutls_x509_crt_get_fingerprint : gnutls_x509_crt_t ->
           gnutls_digest_algorithm_t -> string

    val gnutls_x509_crt_get_key_purpose_oid : gnutls_x509_crt_t -> int -> string * bool

    val gnutls_x509_privkey_init : unit -> gnutls_x509_privkey_t

    val gnutls_x509_privkey_import : gnutls_x509_privkey_t ->
           const_str_datum_p ->
           gnutls_x509_crt_fmt_t -> unit

    val gnutls_x509_privkey_import_pkcs8 : gnutls_x509_privkey_t ->
           const_str_datum_p ->
           gnutls_x509_crt_fmt_t ->
           string -> gnutls_pkcs_encrypt_flags_t -> unit

    val gnutls_x509_crl_init : unit -> gnutls_x509_crl_t

    val gnutls_x509_crl_import : gnutls_x509_crl_t ->
           const_str_datum_p ->
           gnutls_x509_crt_fmt_t -> unit

    val b_error_of_name : string -> error_code

    exception Null_pointer

    exception Error of error_code

    exception Short_memory_buffer of int

    type memory = (char, Bigarray.int8_unsigned_elt, Bigarray.c_layout) Bigarray.Array1.t

See `Netsys_types.memory`

    type gnutls_credentials = [ `Anon_client of gnutls_anon_client_credentials_t
           | `Anon_server of gnutls_anon_server_credentials_t
           | `Certificate of gnutls_certificate_credentials_t
           | `Psk_client of gnutls_psk_client_credentials_t
           | `Psk_server of gnutls_psk_server_credentials_t
           | `Srp_client of gnutls_srp_client_credentials_t
           | `Srp_server of gnutls_srp_server_credentials_t ]

    val gnutls_credentials_set : gnutls_session_t ->
           gnutls_credentials -> unit

    val b_set_pull_callback : gnutls_session_t ->
           (memory -> int) -> unit

Sets the function for reading data. The function must return the number of read bytes (like `Unix.read`). The function can raise `Unix_error`. Only the codes `EINTR`, `EAGAIN`, `EWOULDBLOCK`, and `EMSGSIZE` are interpreted.

    val b_set_push_callback : gnutls_session_t ->
           (memory -> int -> int) -> unit

Sets the function for writing data. The function must return the number of written bytes (like `Unix.write`). The function can raise `Unix_error`. Only the codes `EINTR`, `EAGAIN`, `EWOULDBLOCK`, and `EMSGSIZE` are interpreted.

    val b_set_pull_timeout_callback : gnutls_session_t -> (int -> bool) -> unit

Sets the function for waiting for new data to arrive (only used for DTLS). The integer are the milliseconds to wait at most. The function shall return `true` if there is data, and `false` in case of a timeout. The function can raise `Unix_error`. Only the codes `EINTR`, `EAGAIN`, `EWOULDBLOCK`, and `EMSGSIZE` are interpreted.

    val b_set_verify_callback : gnutls_session_t ->
           (gnutls_session_t -> bool) -> unit

Sets the function for verifying the peer's certificate. The function can return `true` if the certificate is acceptable, and `false` otherwise. Note that this callback is set in this binding on the session, and not on `gnutls_certificate_credentials_t`.

    val set_fd : gnutls_session_t -> Unix.file_descr -> unit

Sets that this file descriptor is used for I/O. NB. This function just invokes `b_set_pull_callback`, `b_set_push_callback`, and `b_set_pull_timeout_callback` with the right argument functions.

    val b_set_db_callbacks : gnutls_session_t ->
           (string -> string -> unit) -> (string -> unit) -> (string -> string) -> unit

`b_set_db_callbacks session store remove retrieve`: sets the three callbacks for server-side session caching

    val string_of_verification_status_flag : gnutls_certificate_status_t_flag -> string

Returns a string for the status code

    val gnutls_x509_crt_list_import : string ->
           gnutls_x509_crt_fmt_t ->
           gnutls_certificate_import_flags ->
           gnutls_x509_crt_t array

    val gnutls_x509_crl_list_import : string ->
           gnutls_x509_crt_fmt_t ->
           gnutls_certificate_import_flags ->
           gnutls_x509_crl_t array