CC: dropbear: split out curve25519 support into a separate config option

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

diff --git a/package/network/services/dropbear/Config.in b/package/network/services/dropbear/Config.in
index e2a7610..19ef71c 100644 (file)
--- a/package/network/services/dropbear/Config.in
+++ b/package/network/services/dropbear/Config.in
@@ -1,6 +1,15 @@
 menu "Configuration"
        depends on PACKAGE_dropbear
 
+config DROPBEAR_CURVE25519
+       bool "Curve25519 support"
+       default n
+       help
+               This enables the following key exchange algorithm:
+                 curve25519-sha256@libssh.org
+
+               Increases binary size by about 13 kB uncompressed (MIPS).
+
 config DROPBEAR_ECC
        bool "Elliptic curve cryptography (ECC)"
        default n
@@ -12,7 +21,6 @@ config DROPBEAR_ECC
                  ecdh-sha2-nistp256
                  ecdh-sha2-nistp384
                  ecdh-sha2-nistp521
-                 curve25519-sha256@libssh.org
 
                Public key algorithms:
                  ecdsa-sha2-nistp256
@@ -22,6 +30,6 @@ config DROPBEAR_ECC
                Does not generate ECC host keys by default (ECC key exchange will not be used,
                only ECC public key auth).
 
-               Increases binary size by about 36 kB (MIPS).
+               Increases binary size by about 23 kB (MIPS).
 
 endmenu

diff --git a/package/network/services/dropbear/Makefile b/package/network/services/dropbear/Makefile
index 4515165..ca67ed3 100644 (file)
--- a/package/network/services/dropbear/Makefile
+++ b/package/network/services/dropbear/Makefile
@@ -23,7 +23,7 @@ PKG_LICENSE_FILES:=LICENSE libtomcrypt/LICENSE libtommath/LICENSE
 PKG_BUILD_PARALLEL:=1
 PKG_USE_MIPS16:=0
 
-PKG_CONFIG_DEPENDS:=CONFIG_DROPBEAR_ECC
+PKG_CONFIG_DEPENDS:=CONFIG_DROPBEAR_ECC CONFIG_DROPBEAR_CURVE25519
 
 include $(INCLUDE_DIR)/package.mk
 
@@ -80,9 +80,16 @@ TARGET_LDFLAGS += -Wl,--gc-sections
 define Build/Configure
        $(Build/Configure/Default)
 
+       awk 'BEGIN { rc = 1 } \
+            /'DROPBEAR_CURVE25519'/ { $$$$0 = "$(if $(CONFIG_DROPBEAR_CURVE25519),,// )#define 'DROPBEAR_CURVE25519'"; rc = 0 } \
+            { print } \
+            END { exit(rc) }' $(PKG_BUILD_DIR)/options.h \
+            >$(PKG_BUILD_DIR)/options.h.new && \
+       mv $(PKG_BUILD_DIR)/options.h.new $(PKG_BUILD_DIR)/options.h
+
        # Enforce that all replacements are made, otherwise options.h has changed
        # format and this logic is broken.
-       for OPTION in DROPBEAR_ECDSA DROPBEAR_ECDH DROPBEAR_CURVE25519; do \
+       for OPTION in DROPBEAR_ECDSA DROPBEAR_ECDH; do \
          awk 'BEGIN { rc = 1 } \
               /'$$$$OPTION'/ { $$$$0 = "$(if $(CONFIG_DROPBEAR_ECC),,// )#define '$$$$OPTION'"; rc = 0 } \
               { print } \