LIBGNUTLS_VERSION

#define LIBGNUTLS_VERSION "1.4.4"

LIBGNUTLS_VERSION_MAJOR

#define LIBGNUTLS_VERSION_MAJOR 1

LIBGNUTLS_VERSION_MINOR

#define LIBGNUTLS_VERSION_MINOR 4

LIBGNUTLS_VERSION_PATCH

#define LIBGNUTLS_VERSION_PATCH 4

LIBGNUTLS_VERSION_NUMBER

#define LIBGNUTLS_VERSION_NUMBER 0x010404

HAVE_SSIZE_T

# define HAVE_SSIZE_T

GNUTLS_CIPHER_RIJNDAEL_128_CBC

#define GNUTLS_CIPHER_RIJNDAEL_128_CBC GNUTLS_CIPHER_AES_128_CBC

GNUTLS_CIPHER_RIJNDAEL_256_CBC

#define GNUTLS_CIPHER_RIJNDAEL_256_CBC GNUTLS_CIPHER_AES_256_CBC

GNUTLS_CIPHER_RIJNDAEL_CBC

#define GNUTLS_CIPHER_RIJNDAEL_CBC GNUTLS_CIPHER_AES_128_CBC

GNUTLS_CIPHER_ARCFOUR

#define GNUTLS_CIPHER_ARCFOUR GNUTLS_CIPHER_ARCFOUR_128

enum gnutls_cipher_algorithm_t

  typedef enum gnutls_cipher_algorithm
  {
    GNUTLS_CIPHER_NULL = 1,
    GNUTLS_CIPHER_ARCFOUR_128,
    GNUTLS_CIPHER_3DES_CBC,
    GNUTLS_CIPHER_AES_128_CBC,
    GNUTLS_CIPHER_AES_256_CBC,
    GNUTLS_CIPHER_ARCFOUR_40,
    GNUTLS_CIPHER_RC2_40_CBC = 90,
    GNUTLS_CIPHER_DES_CBC
  } gnutls_cipher_algorithm_t;

enum gnutls_kx_algorithm_t

  typedef enum
  {
    GNUTLS_KX_RSA = 1,
    GNUTLS_KX_DHE_DSS,
    GNUTLS_KX_DHE_RSA,
    GNUTLS_KX_ANON_DH,
    GNUTLS_KX_SRP,
    GNUTLS_KX_RSA_EXPORT,
    GNUTLS_KX_SRP_RSA,
    GNUTLS_KX_SRP_DSS,
    GNUTLS_KX_PSK,
    GNUTLS_KX_DHE_PSK
  } gnutls_kx_algorithm_t;

enum gnutls_params_type_t

  typedef enum
  {
    GNUTLS_PARAMS_RSA_EXPORT = 1,
    GNUTLS_PARAMS_DH
  } gnutls_params_type_t;

enum gnutls_credentials_type_t

  typedef enum
  {
    GNUTLS_CRD_CERTIFICATE = 1,
    GNUTLS_CRD_ANON,
    GNUTLS_CRD_SRP,
    GNUTLS_CRD_PSK,
    GNUTLS_CRD_IA
  } gnutls_credentials_type_t;

GNUTLS_MAC_SHA

#define GNUTLS_MAC_SHA GNUTLS_MAC_SHA1

GNUTLS_DIG_SHA

#define GNUTLS_DIG_SHA GNUTLS_DIG_SHA1

enum gnutls_mac_algorithm_t

  typedef enum
  {
    GNUTLS_MAC_UNKNOWN = 0,
    GNUTLS_MAC_NULL = 1,
    GNUTLS_MAC_MD5,
    GNUTLS_MAC_SHA1,
    GNUTLS_MAC_RMD160,
    GNUTLS_MAC_MD2
  } gnutls_mac_algorithm_t;

enum gnutls_digest_algorithm_t

  typedef enum
  {
    GNUTLS_DIG_NULL = GNUTLS_MAC_NULL,
    GNUTLS_DIG_MD5 = GNUTLS_MAC_MD5,
    GNUTLS_DIG_SHA1 = GNUTLS_MAC_SHA1,
    GNUTLS_DIG_RMD160 = GNUTLS_MAC_RMD160,
    GNUTLS_DIG_MD2 = GNUTLS_MAC_MD2
  } gnutls_digest_algorithm_t;

GNUTLS_MAX_ALGORITHM_NUM

#define GNUTLS_MAX_ALGORITHM_NUM 16

GNUTLS_COMP_ZLIB

#define GNUTLS_COMP_ZLIB GNUTLS_COMP_DEFLATE

enum gnutls_compression_method_t

  typedef enum
  {
    GNUTLS_COMP_NULL = 1,
    GNUTLS_COMP_DEFLATE,
    GNUTLS_COMP_LZO		/* only available if gnutls-extra has
				   been initialized
				 */
  } gnutls_compression_method_t;

enum gnutls_connection_end_t

  typedef enum
  {
    GNUTLS_SERVER = 1,
    GNUTLS_CLIENT
  } gnutls_connection_end_t;

enum gnutls_alert_level_t

  typedef enum
  {
    GNUTLS_AL_WARNING = 1,
    GNUTLS_AL_FATAL
  } gnutls_alert_level_t;

enum gnutls_alert_description_t

  typedef enum
  {
    GNUTLS_A_CLOSE_NOTIFY,
    GNUTLS_A_UNEXPECTED_MESSAGE = 10,
    GNUTLS_A_BAD_RECORD_MAC = 20,
    GNUTLS_A_DECRYPTION_FAILED,
    GNUTLS_A_RECORD_OVERFLOW,
    GNUTLS_A_DECOMPRESSION_FAILURE = 30,
    GNUTLS_A_HANDSHAKE_FAILURE = 40,
    GNUTLS_A_SSL3_NO_CERTIFICATE = 41,
    GNUTLS_A_BAD_CERTIFICATE = 42,
    GNUTLS_A_UNSUPPORTED_CERTIFICATE,
    GNUTLS_A_CERTIFICATE_REVOKED,
    GNUTLS_A_CERTIFICATE_EXPIRED,
    GNUTLS_A_CERTIFICATE_UNKNOWN,
    GNUTLS_A_ILLEGAL_PARAMETER,
    GNUTLS_A_UNKNOWN_CA,
    GNUTLS_A_ACCESS_DENIED,
    GNUTLS_A_DECODE_ERROR = 50,
    GNUTLS_A_DECRYPT_ERROR,
    GNUTLS_A_EXPORT_RESTRICTION = 60,
    GNUTLS_A_PROTOCOL_VERSION = 70,
    GNUTLS_A_INSUFFICIENT_SECURITY,
    GNUTLS_A_INTERNAL_ERROR = 80,
    GNUTLS_A_USER_CANCELED = 90,
    GNUTLS_A_NO_RENEGOTIATION = 100,
    GNUTLS_A_UNSUPPORTED_EXTENSION = 110,
    GNUTLS_A_CERTIFICATE_UNOBTAINABLE = 111,
    GNUTLS_A_UNRECOGNIZED_NAME = 112,
    GNUTLS_A_UNKNOWN_SRP_USERNAME = 120,
    GNUTLS_A_MISSING_SRP_USERNAME = 121,
    GNUTLS_A_INNER_APPLICATION_FAILURE = 208,
    GNUTLS_A_INNER_APPLICATION_VERIFICATION = 209
  } gnutls_alert_description_t;

enum gnutls_handshake_description_t

  typedef enum
  { GNUTLS_HANDSHAKE_HELLO_REQUEST,
    GNUTLS_HANDSHAKE_CLIENT_HELLO,
    GNUTLS_HANDSHAKE_SERVER_HELLO,
    GNUTLS_HANDSHAKE_CERTIFICATE_PKT = 11,
    GNUTLS_HANDSHAKE_SERVER_KEY_EXCHANGE,
    GNUTLS_HANDSHAKE_CERTIFICATE_REQUEST,
    GNUTLS_HANDSHAKE_SERVER_HELLO_DONE,
    GNUTLS_HANDSHAKE_CERTIFICATE_VERIFY,
    GNUTLS_HANDSHAKE_CLIENT_KEY_EXCHANGE,
    GNUTLS_HANDSHAKE_FINISHED = 20
  } gnutls_handshake_description_t;

enum gnutls_certificate_status_t

  typedef enum
  {
    GNUTLS_CERT_INVALID = 2,	/* will be set if the certificate
				 * was not verified.
				 */
    GNUTLS_CERT_REVOKED = 32,	/* in X.509 this will be set only if CRLs are checked
				 */

    /* Those are extra information about the verification
     * process. Will be set only if the certificate was 
     * not verified.
     */
    GNUTLS_CERT_SIGNER_NOT_FOUND = 64,
    GNUTLS_CERT_SIGNER_NOT_CA = 128,
    GNUTLS_CERT_INSECURE_ALGORITHM = 256
  } gnutls_certificate_status_t;

enum gnutls_certificate_request_t

  typedef enum
  {
    GNUTLS_CERT_IGNORE,
    GNUTLS_CERT_REQUEST = 1,
    GNUTLS_CERT_REQUIRE
  } gnutls_certificate_request_t;

enum gnutls_openpgp_key_status_t

  typedef enum
  { GNUTLS_OPENPGP_KEY,
    GNUTLS_OPENPGP_KEY_FINGERPRINT
  } gnutls_openpgp_key_status_t;

enum gnutls_close_request_t

  typedef enum
  {
    GNUTLS_SHUT_RDWR = 0,
    GNUTLS_SHUT_WR = 1
  } gnutls_close_request_t;

GNUTLS_TLS1

#define GNUTLS_TLS1 GNUTLS_TLS1_0

enum gnutls_protocol_t

  typedef enum
  {
    GNUTLS_SSL3 = 1,
    GNUTLS_TLS1_0,
    GNUTLS_TLS1_1,
    GNUTLS_VERSION_UNKNOWN = 0xff
  } gnutls_protocol_t;

enum gnutls_certificate_type_t

  typedef enum
  {
    GNUTLS_CRT_X509 = 1,
    GNUTLS_CRT_OPENPGP
  } gnutls_certificate_type_t;

enum gnutls_x509_crt_fmt_t

  typedef enum
  {
    GNUTLS_X509_FMT_DER,
    GNUTLS_X509_FMT_PEM
  } gnutls_x509_crt_fmt_t;

enum gnutls_pk_algorithm_t

  typedef enum
  {
    GNUTLS_PK_UNKNOWN = 0,
    GNUTLS_PK_RSA = 1,
    GNUTLS_PK_DSA
  } gnutls_pk_algorithm_t;

gnutls_pk_algorithm_get_name ()

const char* gnutls_pk_algorithm_get_name    (gnutls_pk_algorithm_t algorithm);

GNUTLS_SIGN_RSA_SHA

#define GNUTLS_SIGN_RSA_SHA GNUTLS_SIGN_RSA_SHA1

GNUTLS_SIGN_DSA_SHA

#define GNUTLS_SIGN_DSA_SHA GNUTLS_SIGN_DSA_SHA1

enum gnutls_sign_algorithm_t

  typedef enum
  {
    GNUTLS_SIGN_UNKNOWN = 0,
    GNUTLS_SIGN_RSA_SHA1 = 1,
    GNUTLS_SIGN_DSA_SHA1,
    GNUTLS_SIGN_RSA_MD5,
    GNUTLS_SIGN_RSA_MD2,
    GNUTLS_SIGN_RSA_RMD160
  } gnutls_sign_algorithm_t;

gnutls_sign_algorithm_get_name ()

const char* gnutls_sign_algorithm_get_name  (gnutls_sign_algorithm_talgorithm);

gnutls_transport_ptr_t

  typedef void *gnutls_transport_ptr_t;

struct gnutls_session_int

struct gnutls_session_int;

gnutls_session_t

  typedef struct gnutls_session_int *gnutls_session_t;

struct gnutls_dh_params_int

struct gnutls_dh_params_int;

gnutls_dh_params_t

  typedef struct gnutls_dh_params_int *gnutls_dh_params_t;

struct gnutls_x509_privkey_int

struct gnutls_x509_privkey_int;

gnutls_rsa_params_t

  typedef struct gnutls_x509_privkey_int *gnutls_rsa_params_t;	/* XXX ugly. */

gnutls_init ()

int         gnutls_init                     (gnutls_session_t *session,
                                             gnutls_connection_end_t con_end);

This function initializes the current session to null. Every session must be initialized before use, so internal structures can be allocated. This function allocates structures which can only be free'd by calling gnutls_deinit(). Returns zero on success.

gnutls_deinit ()

void        gnutls_deinit                   (gnutls_session_t session);

This function clears all buffers associated with the session. This function will also remove session data from the session database if the session was terminated abnormally.

gnutls_bye ()

int         gnutls_bye                      (gnutls_session_t session,
                                             gnutls_close_request_t how);

Terminates the current TLS/SSL connection. The connection should have been initiated using gnutls_handshake(). how should be one of GNUTLS_SHUT_RDWR, GNUTLS_SHUT_WR.

In case of GNUTLS_SHUT_RDWR then the TLS connection gets terminated and further receives and sends will be disallowed. If the return value is zero you may continue using the connection. GNUTLS_SHUT_RDWR actually sends an alert containing a close request and waits for the peer to reply with the same message.

In case of GNUTLS_SHUT_WR then the TLS connection gets terminated and further sends will be disallowed. In order to reuse the connection you should wait for an EOF from the peer. GNUTLS_SHUT_WR sends an alert containing a close request.

Note that not all implementations will properly terminate a TLS connection. Some of them, usually for performance reasons, will terminate only the underlying transport layer, thus causing a transmission error to the peer. This error cannot be distinguished from a malicious party prematurely terminating the session, thus this behavior is not recommended.

This function may also return GNUTLS_E_AGAIN or GNUTLS_E_INTERRUPTED; cf. gnutls_record_get_direction().

gnutls_handshake ()

int         gnutls_handshake                (gnutls_session_t session);

This function does the handshake of the TLS/SSL protocol, and initializes the TLS connection.

This function will fail if any problem is encountered, and will return a negative error code. In case of a client, if the client has asked to resume a session, but the server couldn't, then a full handshake will be performed.

The non-fatal errors such as GNUTLS_E_AGAIN and GNUTLS_E_INTERRUPTED interrupt the handshake procedure, which should be later be resumed. Call this function again, until it returns 0; cf. gnutls_record_get_direction() and gnutls_error_is_fatal().

If this function is called by a server after a rehandshake request then GNUTLS_E_GOT_APPLICATION_DATA or GNUTLS_E_WARNING_ALERT_RECEIVED may be returned. Note that these are non fatal errors, only in the specific case of a rehandshake. Their meaning is that the client rejected the rehandshake request.

gnutls_rehandshake ()

int         gnutls_rehandshake              (gnutls_session_t session);

This function will renegotiate security parameters with the client. This should only be called in case of a server.

This message informs the peer that we want to renegotiate parameters (perform a handshake).

If this function succeeds (returns 0), you must call the gnutls_handshake() function in order to negotiate the new parameters.

If the client does not wish to renegotiate parameters he will should with an alert message, thus the return code will be GNUTLS_E_WARNING_ALERT_RECEIVED and the alert will be GNUTLS_A_NO_RENEGOTIATION. A client may also choose to ignore this message.

gnutls_alert_get ()

gnutls_alert_description_t gnutls_alert_get (gnutls_session_t session);

This function will return the last alert number received. This function should be called if GNUTLS_E_WARNING_ALERT_RECEIVED or GNUTLS_E_FATAL_ALERT_RECEIVED has been returned by a gnutls function. The peer may send alerts if he thinks some things were not right. Check gnutls.h for the available alert descriptions.

If no alert has been received the returned value is undefined.

gnutls_alert_send ()

int         gnutls_alert_send               (gnutls_session_t session,
                                             gnutls_alert_level_t level,
                                             gnutls_alert_description_t desc);

This function will send an alert to the peer in order to inform him of something important (eg. his Certificate could not be verified). If the alert level is Fatal then the peer is expected to close the connection, otherwise he may ignore the alert and continue.

The error code of the underlying record send function will be returned, so you may also receive GNUTLS_E_INTERRUPTED or GNUTLS_E_AGAIN as well.

gnutls_alert_send_appropriate ()

int         gnutls_alert_send_appropriate   (gnutls_session_t session,
                                             int err);

Sends an alert to the peer depending on the error code returned by a gnutls function. This function will call gnutls_error_to_alert() to determine the appropriate alert to send.

This function may also return GNUTLS_E_AGAIN, or GNUTLS_E_INTERRUPTED.

If the return value is GNUTLS_E_INVALID_REQUEST, then no alert has been sent to the peer.

gnutls_alert_get_name ()

const char* gnutls_alert_get_name           (gnutls_alert_description_t alert);

This function will return a string that describes the given alert number or NULL. See gnutls_alert_get().

gnutls_cipher_get ()

gnutls_cipher_algorithm_t gnutls_cipher_get (gnutls_session_t session);

gnutls_kx_get ()

gnutls_kx_algorithm_t gnutls_kx_get         (gnutls_session_t session);

gnutls_mac_get ()

gnutls_mac_algorithm_t gnutls_mac_get       (gnutls_session_t session);

gnutls_compression_get ()

gnutls_compression_method_t gnutls_compression_get
                                            (gnutls_session_tsession);

gnutls_certificate_type_get ()

gnutls_certificate_type_t gnutls_certificate_type_get
                                            (gnutls_session_tsession);

gnutls_cipher_get_key_size ()

size_t      gnutls_cipher_get_key_size      (gnutls_cipher_algorithm_t algorithm);

Returns the length (in bytes) of the given cipher's key size.

gnutls_cipher_get_name ()

const char* gnutls_cipher_get_name          (gnutls_cipher_algorithm_t algorithm);

gnutls_mac_get_name ()

const char* gnutls_mac_get_name             (gnutls_mac_algorithm_t algorithm);

gnutls_compression_get_name ()

const char* gnutls_compression_get_name     (gnutls_compression_method_talgorithm);

gnutls_kx_get_name ()

const char* gnutls_kx_get_name              (gnutls_kx_algorithm_t algorithm);

gnutls_certificate_type_get_name ()

const char* gnutls_certificate_type_get_name
                                            (gnutls_certificate_type_ttype);

gnutls_error_is_fatal ()

int         gnutls_error_is_fatal           (int error);

If a function returns a negative value you may feed that value to this function to see if it is fatal. Returns 1 for a fatal error 0 otherwise. However you may want to check the error code manually, since some non-fatal errors to the protocol may be fatal for you (your program).

This is only useful if you are dealing with errors from the record layer or the handshake layer.

gnutls_error_to_alert ()

int         gnutls_error_to_alert           (int err,
                                             int *level);

gnutls_perror ()

void        gnutls_perror                   (int error);

This function is like perror(). The only difference is that it accepts an error number returned by a gnutls function.

gnutls_strerror ()

const char* gnutls_strerror                 (int error);

This function is similar to strerror(). Differences: it accepts an error number returned by a gnutls function; In case of an unknown error a descriptive string is sent instead of NULL.

gnutls_handshake_set_private_extensions ()

void        gnutls_handshake_set_private_extensions
                                            (gnutls_session_t session,
                                             int allow);

This function will enable or disable the use of private cipher suites (the ones that start with 0xFF). By default or if allow is 0 then these cipher suites will not be advertized nor used.

Unless this function is called with the option to allow (1), then no compression algorithms, like LZO. That is because these algorithms are not yet defined in any RFC or even internet draft.

Enabling the private ciphersuites when talking to other than gnutls servers and clients may cause interoperability problems.

gnutls_handshake_get_last_out ()

gnutls_handshake_description_t gnutls_handshake_get_last_out
                                            (gnutls_session_t session);

gnutls_handshake_get_last_in ()

gnutls_handshake_description_t gnutls_handshake_get_last_in
                                            (gnutls_session_t session);

gnutls_record_send ()

ssize_t     gnutls_record_send              (gnutls_session_t session,
                                             const void *data,
                                             size_t sizeofdata);

This function has the similar semantics with send(). The only difference is that is accepts a GNUTLS session, and uses different error codes.

Note that if the send buffer is full, send() will block this function. See the send() documentation for full information. You can replace the default push function by using gnutls_transport_set_ptr2() with a call to send() with a MSG_DONTWAIT flag if blocking is a problem.

If the EINTR is returned by the internal push function (the default is send()} then GNUTLS_E_INTERRUPTED will be returned. If GNUTLS_E_INTERRUPTED or GNUTLS_E_AGAIN is returned, you must call this function again, with the same parameters; alternatively you could provide a NULL pointer for data, and 0 for size. cf. gnutls_record_get_direction().

gnutls_record_recv ()

ssize_t     gnutls_record_recv              (gnutls_session_t session,
                                             void *data,
                                             size_t sizeofdata);

This function has the similar semantics with recv(). The only difference is that is accepts a GNUTLS session, and uses different error codes.

In the special case that a server requests a renegotiation, the client may receive an error code of GNUTLS_E_REHANDSHAKE. This message may be simply ignored, replied with an alert containing NO_RENEGOTIATION, or replied with a new handshake, depending on the client's will.

If EINTR is returned by the internal push function (the default is code{recv()}) then GNUTLS_E_INTERRUPTED will be returned. If GNUTLS_E_INTERRUPTED or GNUTLS_E_AGAIN is returned, you must call this function again, with the same parameters; alternatively you could provide a NULL pointer for data, and 0 for size. cf. code{gnutls_record_get_direction()}.

A server may also receive GNUTLS_E_REHANDSHAKE when a client has initiated a handshake. In that case the server can only initiate a handshake or terminate the connection.

gnutls_read

#define gnutls_read gnutls_record_recv

gnutls_write

#define gnutls_write gnutls_record_send

gnutls_record_get_direction ()

int         gnutls_record_get_direction     (gnutls_session_t session);

This function provides information about the internals of the record protocol and is only useful if a prior gnutls function call (e.g. gnutls_handshake()) was interrupted for some reason, that is, if a function returned GNUTLS_E_INTERRUPTED or GNUTLS_E_AGAIN. In such a case, you might want to call select() or poll() before calling the interrupted gnutls function again. To tell you whether a file descriptor should be selected for either reading or writing, gnutls_record_get_direction() returns 0 if the interrupted function was trying to read data, and 1 if it was trying to write data.

gnutls_record_get_max_size ()

size_t      gnutls_record_get_max_size      (gnutls_session_t session);

This function returns the maximum record packet size in this connection. The maximum record size is negotiated by the client after the first handshake message.

gnutls_record_set_max_size ()

ssize_t     gnutls_record_set_max_size      (gnutls_session_t session,
                                             size_t size);

This function sets the maximum record packet size in this connection. This property can only be set to clients. The server may choose not to accept the requested size.

Acceptable values are 512(=2^9), 1024(=2^10), 2048(=2^11) and 4096(=2^12).

gnutls_record_check_pending ()

size_t      gnutls_record_check_pending     (gnutls_session_t session);

This function checks if there are any data to receive in the gnutls buffers. Returns the size of that data or 0. Notice that you may also use select() to check for data in a TCP connection, instead of this function. (gnutls leaves some data in the tcp buffer in order for select to work).

gnutls_prf ()

int         gnutls_prf                      (gnutls_session_t session,
                                             size_t label_size,
                                             const char *label,
                                             int server_random_first,
                                             size_t extra_size,
                                             const char *extra,
                                             size_t outsize,
                                             char *out);

Apply the TLS Pseudo-Random-Function (PRF) using the master secret on some data, seeded with the client and server random fields.

The label variable usually contain a string denoting the purpose for the generated data. The server_random_first indicate whether the client random field or the server random field should be first in the seed. Non-0 indicate that the server random field is first, 0 that the client random field is first.

The extra variable can be used to add more data to the seed, after the random variables. It can be used to tie make sure the generated output is strongly connected to some additional data (e.g., a string used in user authentication).

The output is placed in *OUT, which must be pre-allocated.

gnutls_prf_raw ()

int         gnutls_prf_raw                  (gnutls_session_t session,
                                             size_t label_size,
                                             const char *label,
                                             size_t seed_size,
                                             const char *seed,
                                             size_t outsize,
                                             char *out);

Apply the TLS Pseudo-Random-Function (PRF) using the master secret on some data.

The label variable usually contain a string denoting the purpose for the generated data. The seed usually contain data such as the client and server random, perhaps together with some additional data that is added to guarantee uniqueness of the output for a particular purpose.

Because the output is not guaranteed to be unique for a particular session unless seed include the client random and server random fields (the PRF would output the same data on another connection resumed from the first one), it is not recommended to use this function directly. The gnutls_prf() function seed the PRF with the client and server random fields directly, and is recommended if you want to generate pseudo random data unique for each session.

enum gnutls_server_name_type_t

  typedef enum
  {
    GNUTLS_NAME_DNS = 1
  } gnutls_server_name_type_t;

gnutls_server_name_set ()

int         gnutls_server_name_set          (gnutls_session_t session,
                                             gnutls_server_name_type_t type,
                                             const void *name,
                                             size_t name_length);

This function is to be used by clients that want to inform (via a TLS extension mechanism) the server of the name they connected to. This should be used by clients that connect to servers that do virtual hosting.

The value of name depends on the ind type. In case of GNUTLS_NAME_DNS, an ASCII or UTF-8 null terminated string, without the trailing dot, is expected. IPv4 or IPv6 addresses are not permitted.

gnutls_server_name_get ()

int         gnutls_server_name_get          (gnutls_session_t session,
                                             void *data,
                                             size_t *data_length,
                                             unsigned int *type,
                                             unsigned int indx);

This function will allow you to get the name indication (if any), a client has sent. The name indication may be any of the enumeration gnutls_server_name_type_t.

If type is GNUTLS_NAME_DNS, then this function is to be used by servers that support virtual hosting, and the data will be a null terminated UTF-8 string.

If data has not enough size to hold the server name GNUTLS_E_SHORT_MEMORY_BUFFER is returned, and data_length will hold the required size.

index is used to retrieve more than one server names (if sent by the client). The first server name has an index of 0, the second 1 and so on. If no name with the given index exists GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE is returned.

gnutls_cipher_set_priority ()

int         gnutls_cipher_set_priority      (gnutls_session_t session,
                                             const int *list);

Sets the priority on the ciphers supported by gnutls. Priority is higher for ciphers specified before others. After specifying the ciphers you want, you must append a 0. Note that the priority is set on the client. The server does not use the algorithm's priority except for disabling algorithms that were not specified.

gnutls_mac_set_priority ()

int         gnutls_mac_set_priority         (gnutls_session_t session,
                                             const int *list);

Sets the priority on the mac algorithms supported by gnutls. Priority is higher for algorithms specified before others. After specifying the algorithms you want, you must append a 0. Note that the priority is set on the client. The server does not use the algorithm's priority except for disabling algorithms that were not specified.

gnutls_compression_set_priority ()

int         gnutls_compression_set_priority (gnutls_session_t session,
                                             const int *list);

Sets the priority on the compression algorithms supported by gnutls. Priority is higher for algorithms specified before others. After specifying the algorithms you want, you must append a 0. Note that the priority is set on the client. The server does not use the algorithm's priority except for disabling algorithms that were not specified.

TLS 1.0 does not define any compression algorithms except NULL. Other compression algorithms are to be considered as gnutls extensions.

gnutls_kx_set_priority ()

int         gnutls_kx_set_priority          (gnutls_session_t session,
                                             const int *list);

Sets the priority on the key exchange algorithms supported by gnutls. Priority is higher for algorithms specified before others. After specifying the algorithms you want, you must append a 0. Note that the priority is set on the client. The server does not use the algorithm's priority except for disabling algorithms that were not specified.

gnutls_protocol_set_priority ()

int         gnutls_protocol_set_priority    (gnutls_session_t session,
                                             const int *list);

Sets the priority on the protocol versions supported by gnutls. This function actually enables or disables protocols. Newer protocol versions always have highest priority.

gnutls_certificate_type_set_priority ()

int         gnutls_certificate_type_set_priority
                                            (gnutls_session_t session,
                                             const int *list);

Sets the priority on the certificate types supported by gnutls. Priority is higher for types specified before others. After specifying the types you want, you must append a 0. Note that the certificate type priority is set on the client. The server does not use the cert type priority except for disabling types that were not specified.

gnutls_set_default_priority ()

int         gnutls_set_default_priority     (gnutls_session_t session);

Sets some default priority on the ciphers, key exchange methods, macs and compression methods. This is to avoid using the gnutls_*_priority() functions, if these defaults are ok. You may override any of the following priorities by calling the appropriate functions.

The order is TLS1, SSL3 for protocols. RSA, DHE_DSS, DHE_RSA for key exchange algorithms. SHA, MD5 and RIPEMD160 for MAC algorithms. AES_128_CBC, 3DES_CBC, and ARCFOUR_128 for ciphers.

gnutls_set_default_export_priority ()

int         gnutls_set_default_export_priority
                                            (gnutls_session_t session);

Sets some default priority on the ciphers, key exchange methods, macs and compression methods. This is to avoid using the gnutls_*_priority() functions, if these defaults are ok. This function also includes weak algorithms. The order is TLS1, SSL3 for protocols, RSA, DHE_DSS, DHE_RSA, RSA_EXPORT for key exchange algorithms. SHA, MD5, RIPEMD160 for MAC algorithms, AES_256_CBC, AES_128_CBC, and 3DES_CBC, ARCFOUR_128, ARCFOUR_40 for ciphers.

gnutls_cipher_suite_get_name ()

const char* gnutls_cipher_suite_get_name    (gnutls_kx_algorithm_tkx_algorithm,
                                             gnutls_cipher_algorithm_tcipher_algorithm,
                                             gnutls_mac_algorithm_tmac_algorithm);

gnutls_protocol_get_version ()

gnutls_protocol_t gnutls_protocol_get_version
                                            (gnutls_session_t session);

gnutls_protocol_get_name ()

const char* gnutls_protocol_get_name        (gnutls_protocol_t version);

gnutls_session_set_data ()

int         gnutls_session_set_data         (gnutls_session_t session,
                                             const void *session_data,
                                             size_t session_data_size);

Sets all session parameters, in order to resume a previously established session. The session data given must be the one returned by gnutls_session_get_data(). This function should be called before gnutls_handshake().

Keep in mind that session resuming is advisory. The server may choose not to resume the session, thus a full handshake will be performed.

gnutls_session_get_data ()

int         gnutls_session_get_data         (gnutls_session_t session,
                                             void *session_data,
                                             size_t *session_data_size);

gnutls_session_get_data2 ()

int         gnutls_session_get_data2        (gnutls_session_t session,
                                             gnutls_datum *data);

GNUTLS_MAX_SESSION_ID

#define GNUTLS_MAX_SESSION_ID 32

gnutls_session_get_id ()

int         gnutls_session_get_id           (gnutls_session_t session,
                                             void *session_id,
                                             size_t *session_id_size);

Returns the current session id. This can be used if you want to check if the next session you tried to resume was actually resumed. This is because resumed sessions have the same sessionID with the original session.

Session id is some data set by the server, that identify the current session. In TLS 1.0 and SSL 3.0 session id is always less than 32 bytes.

TLS_MASTER_SIZE

#define TLS_MASTER_SIZE 48

TLS_RANDOM_SIZE

#define TLS_RANDOM_SIZE 32

gnutls_session_get_server_random ()

const void* gnutls_session_get_server_random
                                            (gnutls_session_t session);

Return a pointer to the 32-byte server random field used in the session. The pointer must not be modified or deallocated.

If a server random value has not yet been established, the output will be garbage; in particular, a NULL return value should not be expected.

gnutls_session_get_client_random ()

const void* gnutls_session_get_client_random
                                            (gnutls_session_t session);

Return a pointer to the 32-byte client random field used in the session. The pointer must not be modified or deallocated.

If a client random value has not yet been established, the output will be garbage; in particular, a NULL return value should not be expected.

gnutls_session_get_master_secret ()

const void* gnutls_session_get_master_secret
                                            (gnutls_session_t session);

Return a pointer to the 48-byte master secret in the session. The pointer must not be modified or deallocated.

If a master secret value has not yet been established, the output will be garbage; in particular, a NULL return value should not be expected.

Consider using gnutls_prf() rather than extracting the master secret and use it to derive further data.

gnutls_session_is_resumed ()

int         gnutls_session_is_resumed       (gnutls_session_t session);

This function will return non zero if this session is a resumed one, or a zero if this is a new session.

gnutls_db_store_func ()

int         (*gnutls_db_store_func)         (void*,
                                             gnutls_datum_t key,
                                             gnutls_datum_t data);

gnutls_db_remove_func ()

int         (*gnutls_db_remove_func)        (void*,
                                             gnutls_datum_t key);

gnutls_db_retr_func ()

gnutls_datum_t (*gnutls_db_retr_func)       (void*,
                                             gnutls_datum_t key);

gnutls_db_set_cache_expiration ()

void        gnutls_db_set_cache_expiration  (gnutls_session_t session,
                                             int seconds);

Sets the expiration time for resumed sessions. The default is 3600 (one hour) at the time writing this.

gnutls_db_remove_session ()

void        gnutls_db_remove_session        (gnutls_session_t session);

This function will remove the current session data from the session database. This will prevent future handshakes reusing these session data. This function should be called if a session was terminated abnormally, and before gnutls_deinit() is called.

Normally gnutls_deinit() will remove abnormally terminated sessions.

gnutls_db_set_retrieve_function ()

void        gnutls_db_set_retrieve_function (gnutls_session_t session,
                                             gnutls_db_retr_func retr_func);

Sets the function that will be used to retrieve data from the resumed sessions database. This function must return a gnutls_datum_t containing the data on success, or a gnutls_datum_t containing null and 0 on failure.

The datum's data must be allocated using the function gnutls_malloc().

The first argument to retr_func() will be null unless gnutls_db_set_ptr() has been called.

gnutls_db_set_remove_function ()

void        gnutls_db_set_remove_function   (gnutls_session_t session,
                                             gnutls_db_remove_func rem_func);

Sets the function that will be used to remove data from the resumed sessions database. This function must return 0 on success.

The first argument to rem_func() will be null unless gnutls_db_set_ptr() has been called.

gnutls_db_set_store_function ()

void        gnutls_db_set_store_function    (gnutls_session_t session,
                                             gnutls_db_store_func store_func);

Sets the function that will be used to store data from the resumed sessions database. This function must remove 0 on success.

The first argument to store_func() will be null unless gnutls_db_set_ptr() has been called.

gnutls_db_set_ptr ()

void        gnutls_db_set_ptr               (gnutls_session_t session,
                                             void *ptr);

Sets the pointer that will be provided to db store, retrieve and delete functions, as the first argument.

gnutls_db_get_ptr ()

void*       gnutls_db_get_ptr               (gnutls_session_t session);

gnutls_db_check_entry ()

int         gnutls_db_check_entry           (gnutls_session_t session,
                                             gnutls_datum_t session_entry);

This function returns GNUTLS_E_EXPIRED, if the database entry has expired or 0 otherwise. This function is to be used when you want to clear unnesessary session which occupy space in your backend.

gnutls_handshake_set_max_packet_length ()

void        gnutls_handshake_set_max_packet_length
                                            (gnutls_session_t session,
                                             size_t max);

This function will set the maximum size of a handshake message. Handshake messages over this size are rejected. The default value is 16kb which is large enough. Set this to 0 if you do not want to set an upper limit.

gnutls_check_version ()

const char* gnutls_check_version            (const char *req_version);

Check that the version of the library is at minimum the requested one and return the version string; return NULL if the condition is not satisfied. If a NULL is passed to this function, no check is done, but the version string is simply returned.

gnutls_credentials_clear ()

void        gnutls_credentials_clear        (gnutls_session_t session);

Clears all the credentials previously set in this session.

gnutls_credentials_set ()

int         gnutls_credentials_set          (gnutls_session_t session,
                                             gnutls_credentials_type_t type,
                                             void *cred);

Sets the needed credentials for the specified type. Eg username, password - or public and private keys etc. The (void* cred) parameter is a structure that depends on the specified type and on the current session (client or server). [ In order to minimize memory usage, and share credentials between several threads gnutls keeps a pointer to cred, and not the whole cred structure. Thus you will have to keep the structure allocated until you call gnutls_deinit(). ]

For GNUTLS_CRD_ANON cred should be gnutls_anon_client_credentials_t in case of a client. In case of a server it should be gnutls_anon_server_credentials_t.

For GNUTLS_CRD_SRP cred should be gnutls_srp_client_credentials_t in case of a client, and gnutls_srp_server_credentials_t, in case of a server.

For GNUTLS_CRD_CERTIFICATE cred should be gnutls_certificate_credentials_t.

gnutls_cred_set

#define gnutls_cred_set	gnutls_credentials_set

struct gnutls_certificate_credentials_st

struct gnutls_certificate_credentials_st;

gnutls_anon_free_server_credentials ()

void        gnutls_anon_free_server_credentials
                                            (gnutls_anon_server_credentials_t sc);

This structure is complex enough to manipulate directly thus this helper function is provided in order to free (deallocate) it.

gnutls_anon_allocate_server_credentials ()

int         gnutls_anon_allocate_server_credentials
                                            (gnutls_anon_server_credentials_t *sc);

This structure is complex enough to manipulate directly thus this helper function is provided in order to allocate it.

gnutls_anon_set_server_dh_params ()

void        gnutls_anon_set_server_dh_params
                                            (gnutls_anon_server_credentials_t res,
                                             gnutls_dh_params_t dh_params);

This function will set the diffie hellman parameters for an anonymous server to use. These parameters will be used in Anonymous Diffie Hellman cipher suites.

gnutls_anon_set_server_params_function ()

void        gnutls_anon_set_server_params_function
                                            (gnutls_anon_server_credentials_tres,
                                             gnutls_params_function *func);

This function will set a callback in order for the server to get the diffie hellman parameters for anonymous authentication. The callback should return zero on success.

gnutls_anon_free_client_credentials ()

void        gnutls_anon_free_client_credentials
                                            (gnutls_anon_client_credentials_tsc);

This structure is complex enough to manipulate directly thus this helper function is provided in order to free (deallocate) it.

gnutls_anon_allocate_client_credentials ()

int         gnutls_anon_allocate_client_credentials
                                            (gnutls_anon_client_credentials_t *sc);

This structure is complex enough to manipulate directly thus this helper function is provided in order to allocate it.

gnutls_certificate_free_credentials ()

void        gnutls_certificate_free_credentials
                                            (gnutls_certificate_credentials_tsc);

This structure is complex enough to manipulate directly thus this helper function is provided in order to free (deallocate) it.

This function does not free any temporary parameters associated with this structure (ie RSA and DH parameters are not freed by this function).

gnutls_certificate_allocate_credentials ()

int         gnutls_certificate_allocate_credentials
                                            (gnutls_certificate_credentials_t *res);

This structure is complex enough to manipulate directly thus this helper function is provided in order to allocate it.

gnutls_certificate_free_keys ()

void        gnutls_certificate_free_keys    (gnutls_certificate_credentials_t sc);

This function will delete all the keys and the certificates associated with the given credentials. This function must not be called when a TLS negotiation that uses the credentials is in progress.

gnutls_certificate_free_cas ()

void        gnutls_certificate_free_cas     (gnutls_certificate_credentials_t sc);

This function will delete all the CAs associated with the given credentials. Servers that do not use gnutls_certificate_verify_peers2() may call this to save some memory.

gnutls_certificate_free_ca_names ()

void        gnutls_certificate_free_ca_names
                                            (gnutls_certificate_credentials_t sc);

This function will delete all the CA name in the given credentials. Clients may call this to save some memory since in client side the CA names are not used.

CA names are used by servers to advertize the CAs they support to clients.

gnutls_certificate_free_crls ()

void        gnutls_certificate_free_crls    (gnutls_certificate_credentials_t sc);

This function will delete all the CRLs associated with the given credentials.

gnutls_certificate_set_dh_params ()

void        gnutls_certificate_set_dh_params
                                            (gnutls_certificate_credentials_t res,
                                             gnutls_dh_params_t dh_params);

This function will set the diffie hellman parameters for a certificate server to use. These parameters will be used in Ephemeral Diffie Hellman cipher suites. Note that only a pointer to the parameters are stored in the certificate handle, so if you deallocate the parameters before the certificate is deallocated, you must change the parameters stored in the certificate first.

gnutls_certificate_set_rsa_export_params ()

void        gnutls_certificate_set_rsa_export_params
                                            (gnutls_certificate_credentials_tres,
                                             gnutls_rsa_params_t rsa_params);

This function will set the temporary RSA parameters for a certificate server to use. These parameters will be used in RSA-EXPORT cipher suites.

gnutls_certificate_set_verify_flags ()

void        gnutls_certificate_set_verify_flags
                                            (gnutls_certificate_credentials_tres,
                                             unsigned int flags);

This function will set the flags to be used at verification of the certificates. Flags must be OR of the gnutls_certificate_verify_flags enumerations.

gnutls_certificate_set_verify_limits ()

void        gnutls_certificate_set_verify_limits
                                            (gnutls_certificate_credentials_tres,
                                             unsigned int max_bits,
                                             unsigned int max_depth);

This function will set some upper limits for the default verification function, gnutls_certificate_verify_peers2(), to avoid denial of service attacks.

gnutls_certificate_set_x509_trust_file ()

int         gnutls_certificate_set_x509_trust_file
                                            (gnutls_certificate_credentials_tres,
                                             const char *CAFILE,
                                             gnutls_x509_crt_fmt_t type);

This function adds the trusted CAs in order to verify client or server certificates. In case of a client this is not required to be called if the certificates are not verified using gnutls_certificate_verify_peers2(). This function may be called multiple times.

In case of a server the names of the CAs set here will be sent to the client if a certificate request is sent. This can be disabled using gnutls_certificate_send_x509_rdn_sequence().

gnutls_certificate_set_x509_trust_mem ()

int         gnutls_certificate_set_x509_trust_mem
                                            (gnutls_certificate_credentials_tres,
                                             const gnutls_datum_t *CA,
                                             gnutls_x509_crt_fmt_t type);

This function adds the trusted CAs in order to verify client or server certificates. In case of a client this is not required to be called if the certificates are not verified using gnutls_certificate_verify_peers2(). This function may be called multiple times.

In case of a server the CAs set here will be sent to the client if a certificate request is sent. This can be disabled using gnutls_certificate_send_x509_rdn_sequence().

gnutls_certificate_set_x509_crl_file ()

int         gnutls_certificate_set_x509_crl_file
                                            (gnutls_certificate_credentials_tres,
                                             const char *crlfile,
                                             gnutls_x509_crt_fmt_t type);

This function adds the trusted CRLs in order to verify client or server certificates. In case of a client this is not required to be called if the certificates are not verified using gnutls_certificate_verify_peers2(). This function may be called multiple times.

gnutls_certificate_set_x509_crl_mem ()

int         gnutls_certificate_set_x509_crl_mem
                                            (gnutls_certificate_credentials_tres,
                                             const gnutls_datum_t *CRL,
                                             gnutls_x509_crt_fmt_t type);

This function adds the trusted CRLs in order to verify client or server certificates. In case of a client this is not required to be called if the certificates are not verified using gnutls_certificate_verify_peers2(). This function may be called multiple times.

gnutls_certificate_set_x509_key_file ()

int         gnutls_certificate_set_x509_key_file
                                            (gnutls_certificate_credentials_tres,
                                             const char *CERTFILE,
                                             const char *KEYFILE,
                                             gnutls_x509_crt_fmt_t type);

This function sets a certificate/private key pair in the gnutls_certificate_credentials_t structure. This function may be called more than once (in case multiple keys/certificates exist for the server).

Currently only PKCS-1 encoded RSA and DSA private keys are accepted by this function.

gnutls_certificate_set_x509_key_mem ()

int         gnutls_certificate_set_x509_key_mem
                                            (gnutls_certificate_credentials_tres,
                                             const gnutls_datum_t *CERT,
                                             const gnutls_datum_t *KEY,
                                             gnutls_x509_crt_fmt_t type);

This function sets a certificate/private key pair in the gnutls_certificate_credentials_t structure. This function may be called more than once (in case multiple keys/certificates exist for the server).

Currently are supported: RSA PKCS-1 encoded private keys, DSA private keys.

DSA private keys are encoded the OpenSSL way, which is an ASN.1 DER sequence of 6 INTEGERs - version, p, q, g, pub, priv.

Note that the keyUsage (2.5.29.15) PKIX extension in X.509 certificates is supported. This means that certificates intended for signing cannot be used for ciphersuites that require encryption.

If the certificate and the private key are given in PEM encoding then the strings that hold their values must be null terminated.

gnutls_certificate_set_x509_simple_pkcs12_file ()

int         gnutls_certificate_set_x509_simple_pkcs12_file
                                            (gnutls_certificate_credentials_t res,
                                             const char *pkcs12file,
                                             gnutls_x509_crt_fmt_t type,
                                             const char *password);

This function sets a certificate/private key pair and/or a CRL in the gnutls_certificate_credentials_t structure. This function may be called more than once (in case multiple keys/certificates exist for the server).

MAC:ed PKCS12 files are supported. Encrypted PKCS12 bags are supported. Encrypted PKCS8 private keys are supported. However, only password based security, and the same password for all operations, are supported.

The private keys may be RSA PKCS1 or DSA private keys encoded in the OpenSSL way.

PKCS12 file may contain many keys and/or certificates, and there is no way to identify which key/certificate pair you want. You should make sure the PKCS12 file only contain one key/certificate pair and/or one CRL.

It is believed that the limitations of this function is acceptable for most usage, and that any more flexibility would introduce complexity that would make it harder to use this functionality at all.

gnutls_x509_privkey_t

  typedef struct gnutls_x509_privkey_int *gnutls_x509_privkey_t;

struct gnutls_x509_crl_int

struct gnutls_x509_crl_int;

gnutls_x509_crl_t

  typedef struct gnutls_x509_crl_int *gnutls_x509_crl_t;

struct gnutls_x509_crt_int

struct gnutls_x509_crt_int;

gnutls_x509_crt_t

  typedef struct gnutls_x509_crt_int *gnutls_x509_crt_t;

gnutls_certificate_set_x509_key ()

int         gnutls_certificate_set_x509_key (gnutls_certificate_credentials_t res,
                                             gnutls_x509_crt_t *cert_list,
                                             int cert_list_size,
                                             gnutls_x509_privkey_t key);

This function sets a certificate/private key pair in the gnutls_certificate_credentials_t structure. This function may be called more than once (in case multiple keys/certificates exist for the server).

gnutls_certificate_set_x509_trusta href="gnutls-gnutls.html#gnutls-x509-crtft" valign="top"> res : is an gnutls_certificate_credentials_t structure. cert_list : contains a certificate list (path) for the specified private key cert_list_size : holds the size of the certificate list key : is a gnutls_x509_privkey_t key Returns :