diff --git a/src/crypto/hash_df.c b/src/crypto/hash_df.c
index 9e3da181..1074f8ca 100644
--- a/src/crypto/hash_df.c
+++ b/src/crypto/hash_df.c
@@ -37,6 +37,7 @@ FILE_LICENCE ( GPL2_OR_LATER );
 
 #include <stdint.h>
 #include <string.h>
+#include <assert.h>
 #include <byteswap.h>
 #include <ipxe/crypto.h>
 #include <ipxe/hash_df.h>
diff --git a/src/crypto/hmac_drbg.c b/src/crypto/hmac_drbg.c
index efbd67dc..9e70e4e6 100644
--- a/src/crypto/hmac_drbg.c
+++ b/src/crypto/hmac_drbg.c
@@ -38,6 +38,7 @@ FILE_LICENCE ( GPL2_OR_LATER );
 #include <stdint.h>
 #include <string.h>
 #include <errno.h>
+#include <assert.h>
 #include <ipxe/crypto.h>
 #include <ipxe/hmac.h>
 #include <ipxe/hmac_drbg.h>