diff --git a/boot/zephyr/CMakeLists.txt b/boot/zephyr/CMakeLists.txt
index c382c528..cda5a48e 100644
--- a/boot/zephyr/CMakeLists.txt
+++ b/boot/zephyr/CMakeLists.txt
@@ -141,6 +141,16 @@ if(CONFIG_BOOT_SIGNATURE_TYPE_ECDSA_P256 OR CONFIG_BOOT_ENCRYPT_EC256)
   zephyr_library_compile_definitions(
     MBEDTLS_CONFIG_FILE="${CMAKE_CURRENT_LIST_DIR}/include/mcuboot-mbedtls-cfg.h"
     )
+elseif(CONFIG_BOOT_SIGNATURE_TYPE_NONE)
+  zephyr_library_include_directories(
+    ${BOOT_DIR}/zephyr/include
+    ${TINYCRYPT_DIR}/include
+    )
+
+  zephyr_library_sources(
+    ${TINYCRYPT_DIR}/source/sha256.c
+    ${TINYCRYPT_DIR}/source/utils.c
+    )
 elseif(CONFIG_BOOT_SIGNATURE_TYPE_RSA)
   # Use mbedTLS provided by Zephyr for RSA signatures. (Its config file
   # is set using Kconfig.)
diff --git a/boot/zephyr/Kconfig b/boot/zephyr/Kconfig
index b1969529..3b5f91fd 100644
--- a/boot/zephyr/Kconfig
+++ b/boot/zephyr/Kconfig
@@ -62,6 +62,10 @@ choice
 	prompt "Signature type"
 	default BOOT_SIGNATURE_TYPE_RSA
 
+config BOOT_SIGNATURE_TYPE_NONE
+	bool "No signature; use only hash check"
+	select BOOT_USE_TINYCRYPT
+
 config BOOT_SIGNATURE_TYPE_RSA
 	bool "RSA signatures"
 	select BOOT_USE_MBEDTLS
diff --git a/boot/zephyr/keys.c b/boot/zephyr/keys.c
index 5dd0ca28..72147483 100644
--- a/boot/zephyr/keys.c
+++ b/boot/zephyr/keys.c
@@ -41,8 +41,6 @@ extern unsigned int ecdsa_pub_key_len;
 #define HAVE_KEYS
 extern const unsigned char ed25519_pub_key[];
 extern unsigned int ed25519_pub_key_len;
-#else
-#error "No public key available for given signing algorithm."
 #endif
 
 /*
diff --git a/boot/zephyr/prj.conf b/boot/zephyr/prj.conf
index 71e9a2a3..17826db0 100644
--- a/boot/zephyr/prj.conf
+++ b/boot/zephyr/prj.conf
@@ -15,6 +15,7 @@ CONFIG_BOOT_UPGRADE_ONLY=n
 CONFIG_BOOT_BOOTSTRAP=n
 
 ### Default to RSA
+CONFIG_BOOT_SIGNATURE_TYPE_NONE=n
 CONFIG_BOOT_SIGNATURE_TYPE_RSA=y
 CONFIG_BOOT_SIGNATURE_TYPE_RSA_LEN=2048
 CONFIG_BOOT_SIGNATURE_TYPE_ECDSA_P256=n