dropbear: roll up recipes into mapping lists

this commit removes manual recipes for options and introduces mapping lists:
- DB_OPT_COMMON holds option mappings which are common for all builds;
- DB_OPT_CONFIG holds option mappings which are depend on config settings.

DB_OPT_COMMON is space-separated list of 'words', each of them is in format:
  'header_option|value'

'header_option' is added with value 'value' to 'localoptions.h'.

if 'header_option' is preceded by two exclamation marks ('!!')
then option is not added to 'localoptions.h' but replaced in 'sysoptions.h'.

in short:
   option|value - add option to localoptions.h
 !!option|value - replace option in sysoptions.h

DB_OPT_CONFIG is space-separated list of 'words', each of them is in format:
  'header_option|config_variable|value_enabled|value_disabled'

'header_option' is handled likewise in DB_OPT_COMMON.

if 'config_variable' is enabled (technically: not disabled)
then 'header_option' is set to 'value_enabled' and 'value_disabled' otherwise.

in short:
   option|config|enabled|disabled = add option to localoptions.h
 !!option|config|enabled|disabled = replace option in sysoptions.h

   option := (config) ? enabled : disabled

If you're not sure that option's value doesn't have '|' within - add your recipe
manually right after '$(Build/Configure/dropbear_headers)' and write some words
about your decision.

PS about two exclamation marks:
early idea was to use one exclamation mark to denote such header options
but then i thought single exclamation mark may be overlooked by mistake.

Signed-off-by: Konstantin Demin <rockdrilla@gmail.com>
This commit is contained in:
Konstantin Demin 2020-11-25 06:12:41 +03:00 committed by Petr Štetiar
parent 79d5c24724
commit e1bd9645b6

View File

@ -96,41 +96,76 @@ CONFIGURE_ARGS += \
$(if $(CONFIG_DROPBEAR_ZLIB),,--disable-zlib) \
--enable-bundled-libtom
##############################################################################
#
# option|value - add option to localoptions.h
# !!option|value - replace option in sysoptions.h
#
##############################################################################
# remove protocol idented software version number:
# - LOCAL_IDENT
# disable legacy/unsafe methods and unused functionality:
# - INETD_MODE
# - DROPBEAR_CLI_NETCAT
# - DROPBEAR_DSS
# - DO_MOTD
DB_OPT_COMMON = \
DEFAULT_PATH|"$(TARGET_INIT_PATH)" \
!!LOCAL_IDENT|"SSH-2.0-dropbear" \
INETD_MODE|0 \
DROPBEAR_CLI_NETCAT|0 \
DROPBEAR_DSS|0 \
DO_MOTD|0 \
##############################################################################
#
# option|config|enabled|disabled = add option to localoptions.h
# !!option|config|enabled|disabled = replace option in sysoptions.h
#
# option := (config) ? enabled : disabled
#
##############################################################################
DB_OPT_CONFIG = \
DROPBEAR_CURVE25519|CONFIG_DROPBEAR_CURVE25519|1|0 \
DROPBEAR_ED25519|CONFIG_DROPBEAR_ED25519|1|0 \
DROPBEAR_CHACHA20POLY1305|CONFIG_DROPBEAR_CHACHA20POLY1305|1|0 \
DROPBEAR_ECDSA|CONFIG_DROPBEAR_ECC|1|0 \
DROPBEAR_ECDH|CONFIG_DROPBEAR_ECC|1|0 \
!!DROPBEAR_ECC_384|CONFIG_DROPBEAR_ECC_FULL|1|0 \
!!DROPBEAR_ECC_521|CONFIG_DROPBEAR_ECC_FULL|1|0 \
TARGET_CFLAGS += -DARGTYPE=3 -ffunction-sections -fdata-sections -flto
TARGET_LDFLAGS += -Wl,--gc-sections -flto=jobserver
db_opt_add =echo '\#define $(1) $(2)' >> $(PKG_BUILD_DIR)/localoptions.h
db_opt_replace =$(ESED) 's,^(\#define $(1)) .*$$$$,\1 $(2),g' $(PKG_BUILD_DIR)/sysoptions.h
define Build/Configure/dropbear_headers
$(strip $(foreach s,$(DB_OPT_COMMON), \
$(if $(filter !!%,$(word 1,$(subst |, ,$(s)))), \
$(call db_opt_replace,$(patsubst !!%,%,$(word 1,$(subst |, ,$(s)))),$(word 2,$(subst |, ,$(s)))), \
$(call db_opt_add,$(word 1,$(subst |, ,$(s))),$(word 2,$(subst |, ,$(s)))) \
) ; \
))
$(strip $(foreach s,$(DB_OPT_CONFIG), \
$(if $(filter !!%,$(word 1,$(subst |, ,$(s)))), \
$(call db_opt_replace,$(patsubst !!%,%,$(word 1,$(subst |, ,$(s)))),$(if $($(word 2,$(subst |, ,$(s)))),$(word 3,$(subst |, ,$(s))),$(word 4,$(subst |, ,$(s))))), \
$(call db_opt_add,$(word 1,$(subst |, ,$(s))),$(if $($(word 2,$(subst |, ,$(s)))),$(word 3,$(subst |, ,$(s))),$(word 4,$(subst |, ,$(s))))) \
) ; \
))
endef
define Build/Configure
: > $(PKG_BUILD_DIR)/localoptions.h
$(Build/Configure/Default)
$(call db_opt_add,DEFAULT_PATH,"$(TARGET_INIT_PATH)")
# remove protocol idented software version number
$(call db_opt_replace,LOCAL_IDENT,"SSH-2.0-dropbear")
# disable legacy/unsafe methods and unused functionality
$(foreach opt,INETD_MODE DROPBEAR_CLI_NETCAT DROPBEAR_DSS DO_MOTD, \
$(call db_opt_add,$(opt),0) ; \
)
$(call db_opt_add,DROPBEAR_CURVE25519,$(if $(CONFIG_DROPBEAR_CURVE25519),1,0))
$(call db_opt_add,DROPBEAR_ED25519,$(if $(CONFIG_DROPBEAR_ED25519),1,0))
$(call db_opt_add,DROPBEAR_CHACHA20POLY1305,$(if $(CONFIG_DROPBEAR_CHACHA20POLY1305),1,0))
$(foreach opt,DROPBEAR_ECDSA DROPBEAR_ECDH, \
$(call db_opt_add,$(opt),$(if $(CONFIG_DROPBEAR_ECC),1,0)) ; \
)
# enable nistp384 and nistp521 only if full ECC support was requested
$(foreach opt,DROPBEAR_ECC_384 DROPBEAR_ECC_521, \
$(call db_opt_replace,$(opt),$(if $(CONFIG_DROPBEAR_ECC_FULL),1,0)) ; \
)
$(Build/Configure/dropbear_headers)
# Enforce rebuild of svr-chansession.c
rm -f $(PKG_BUILD_DIR)/svr-chansession.o