COAP_TLS_LIBRARY(3)

NAME
coap_tls_library, coap_dtls_is_supported, coap_tls_is_supported, coap_get_tls_library_version - work with CoAP contexts

SYNOPSIS
#include <coap/coap.h> int coap_dtls_is_supported(void); int coap_tls_is_supported(void); coap_tls_version_t *coap_get_tls_library_version(void); Link with -lcoap-2, -lcoap-2-openssl or -lcoap-2-tinydtls depending on your (D)TLS library type.

DESCRIPTION
When the libcoap library was built, it will have been compiled using a specific TLS implementation type (e.g. OpenSSL, GnuTLS, TinyDTLS or noTLS). When the libcoap library is linked into an application, it is possible that the application needs to dynamically determine whether DTLS or TLS is supported, what type of TLS implementation libcoap was compiled with, as well as detect what is the version of the currently loaded TLS library is. NOTE: If OpenSSL is being used, then the minimum OpenSSL library version is 1.1.0. Network traffic can be encrypted or un-encrypted with libcoap - how to set this up is described in coap_context(3). Due to the nature of TLS, there can be Callbacks that are invoked as the TLS session negotiates encryption algorithms, encryption keys etc. Where possible, by default, the CoAP layer handles all this automatically. However, there is the flexibility of the Callbacks for imposing additional security checks etc. when PKI is being used. These callbacks need to need to match the TLS implementation type. The coap_dtls_is_supported() function returns 1 if support for DTLS is enabled, otherwise 0; The coap_tls_is_supported() function returns 1 if support for TLS is enabled, otherwise 0; The coap_get_tls_library_version() function returns the TLS implementation type and library version in a coap_tls_version_t* structure.
#define COAP_TLS_LIBRARY_NOTLS    0
#define COAP_TLS_LIBRARY_TINYDTLS 1
#define COAP_TLS_LIBRARY_OPENSSL  2
#define COAP_TLS_LIBRARY_GNUTLS   3
typedef struct coap_tls_version_t {
  uint64_t version; /* Library Version as returned by the TLS library */
  int type; /* One of COAP_TLS_LIBRARY_* */
}

RETURN VALUES
coap_dtls_is_supported() and coap_tls_is_supported() functions return 0 on failure, 1 on success. coap_get_tls_library_version() function returns the TLS implementation type and library version in a coap_tls_version_t* structure.

SEE ALSO
coap_context(3).

FURTHER INFORMATION
See "RFC7252: The Constrained Application Protocol (CoAP)" for further information.

BUGS
Please report bugs on the mailing list for libcoap: libcoap-developers@lists.sourceforge.net

AUTHORS
The libcoap project <libcoap-developers@lists.sourceforge.net>