RIOT/pkg/tinydtls/Makefile.include

PKG_BUILDDIR ?= $(PKGDIRBASE)/tinydtls

INCLUDES += -I$(PKG_BUILDDIR)

ifeq ($(TOOLCHAIN), llvm)
  CFLAGS += -Wno-gnu-zero-variadic-macro-arguments -Wno-unused-function
endif

INCLUDES += -I$(RIOTBASE)/pkg/tinydtls/include
INCLUDES += -I$(PKG_BUILDDIR)
# Mandatory for tinyDTLS
CFLAGS += -DDTLSv12 -DWITH_SHA256

# Check that the used PRNG implementation is cryptographically secure
CRYPTO_SECURE_IMPLEMENTATIONS := prng_sha256prng prng_sha1prng prng_hwrng
USED_PRNG_IMPLEMENTATIONS := $(filter prng_%,$(USEMODULE))
ifeq (,$(filter $(CRYPTO_SECURE_IMPLEMENTATIONS),$(USEMODULE)))
  $(info TinyDTLS needs a cryptographically secure implementation of the PRNG module.)
  $(info Currently using: $(USED_PRNG_IMPLEMENTATIONS))
  $(error Please use one of: $(CRYPTO_SECURE_IMPLEMENTATIONS))
endif

# Dependencies partially under control of the App's requirements

# The configuration for socket overrides Sock
ifeq (,$(filter posix_sockets,$(USEMODULE)))
  CFLAGS += -DWITH_RIOT_SOCK
endif

# Default cipher suite when not using Kconfig
ifeq (,$(CONFIG_KCONFIG_USEPKG_TINYDTLS))
  # NOTE: PSK should be enabled by default BUT if the user define any other cipher
  #       suite(s) it should not be enabled.
  # TODO: Create the flag DTLS_CIPHERS with keywords PSK, ECC (and future)
  PSK_ENABLED := $(or $(filter -DCONFIG_DTLS_PSK,$(CFLAGS)), $(filter -DDTLS_PSK,$(CFLAGS)))
  ECC_ENABLED := $(or $(filter -DCONFIG_DTLS_ECC,$(CFLAGS)), $(filter -DDTLS_ECC,$(CFLAGS)))
  ifeq (, $(or $(PSK_ENABLED),$(ECC_ENABLED)))
    CFLAGS += -DCONFIG_DTLS_PSK
  endif
endif

# For now contrib only contains sock_dtls adaption
ifneq (,$(filter tinydtls_sock_dtls,$(USEMODULE)))
  DIRS += $(RIOTBASE)/pkg/tinydtls/contrib
endif

# Translate 'CONFIG_' options to package specific flags. This checks if the
# option is being set via Kconfig or CFLAGS

ifneq (,$(or $(CONFIG_DTLS_PSK),$(filter -DCONFIG_DTLS_PSK,$(CFLAGS))))
    CFLAGS += -DDTLS_PSK
endif

ifneq (,$(or $(CONFIG_DTLS_ECC),$(filter -DCONFIG_DTLS_ECC,$(CFLAGS))))
    CFLAGS += -DDTLS_ECC
endif

CONTEXT_MAX := $(or $(CONFIG_DTLS_CONTEXT_MAX),$(patsubst -DCONFIG_DTLS_CONTEXT_MAX=%,%,$(filter -DCONFIG_DTLS_CONTEXT_MAX=%,$(CFLAGS))))
ifneq (,$(CONTEXT_MAX))
    CFLAGS += -DDTLS_CONTEXT_MAX=$(CONTEXT_MAX)
endif

PEER_MAX := $(or $(CONFIG_DTLS_PEER_MAX),$(patsubst -DCONFIG_DTLS_PEER_MAX=%,%,$(filter -DCONFIG_DTLS_PEER_MAX=%,$(CFLAGS))))
ifneq (,$(PEER_MAX))
    CFLAGS += -DDTLS_PEER_MAX=$(PEER_MAX)
else ifneq (,$(filter gcoap_dtls,$(USEMODULE)))
    # The default value in sys/include/net/dtls.h for CONFIG_DTLS_PEER_MAX is 2
    # when gcoap_dtls is active, otherwise 1. As the default in tinydtls is 1,
    # we need to set it explicitly if the dtls.h default value deviates from
    # the tinydtls default.
    CFLAGS += -DDTLS_PEER_MAX=2
endif

HANDSHAKE_MAX := $(or $(CONFIG_DTLS_HANDSHAKE_MAX),$(patsubst -DCONFIG_DTLS_HANDSHAKE_MAX=%,%,$(filter -DCONFIG_DTLS_HANDSHAKE_MAX=%,$(CFLAGS))))
ifneq (,$(HANDSHAKE_MAX))
    CFLAGS += -DDTLS_HANDSHAKE_MAX=$(HANDSHAKE_MAX)
endif

DTLS_MAX_BUF ?= 200
CFLAGS += "-DDTLS_MAX_BUF=$(DTLS_MAX_BUF)"