diff --git a/sys/geom/eli/g_eli.h b/sys/geom/eli/g_eli.h
index 36ab0b87649e..6c8c22a2a97d 100644
--- a/sys/geom/eli/g_eli.h
+++ b/sys/geom/eli/g_eli.h
@@ -721,12 +721,12 @@ struct hmac_ctx {
 	SHA512_CTX	outerctx;
 };
 
-void g_eli_crypto_hmac_init(struct hmac_ctx *ctx, const uint8_t *hkey,
+void g_eli_crypto_hmac_init(struct hmac_ctx *ctx, const char hkey[],
     size_t hkeylen);
 void g_eli_crypto_hmac_update(struct hmac_ctx *ctx, const uint8_t *data,
     size_t datasize);
 void g_eli_crypto_hmac_final(struct hmac_ctx *ctx, uint8_t *md, size_t mdsize);
-void g_eli_crypto_hmac(const uint8_t *hkey, size_t hkeysize,
+void g_eli_crypto_hmac(const char hkey[], size_t hkeysize,
     const uint8_t *data, size_t datasize, uint8_t *md, size_t mdsize);
 
 void g_eli_key_fill(struct g_eli_softc *sc, struct g_eli_key *key,
diff --git a/sys/geom/eli/g_eli_hmac.c b/sys/geom/eli/g_eli_hmac.c
index dd3140d15b29..7d5a83820103 100644
--- a/sys/geom/eli/g_eli_hmac.c
+++ b/sys/geom/eli/g_eli_hmac.c
@@ -46,7 +46,7 @@ __FBSDID("$FreeBSD$");
 #include <geom/eli/g_eli.h>
 
 void
-g_eli_crypto_hmac_init(struct hmac_ctx *ctx, const uint8_t *hkey,
+g_eli_crypto_hmac_init(struct hmac_ctx *ctx, const char hkey[],
     size_t hkeylen)
 {
 	u_char k_ipad[128], k_opad[128], key[128];
@@ -110,7 +110,7 @@ g_eli_crypto_hmac_final(struct hmac_ctx *ctx, uint8_t *md, size_t mdsize)
 }
 
 void
-g_eli_crypto_hmac(const uint8_t *hkey, size_t hkeysize, const uint8_t *data,
+g_eli_crypto_hmac(const char hkey[], size_t hkeysize, const uint8_t *data,
     size_t datasize, uint8_t *md, size_t mdsize)
 {
 	struct hmac_ctx ctx;
diff --git a/sys/geom/eli/pkcs5v2.c b/sys/geom/eli/pkcs5v2.c
index 0006fe0de1f1..defe91b45500 100644
--- a/sys/geom/eli/pkcs5v2.c
+++ b/sys/geom/eli/pkcs5v2.c
@@ -52,7 +52,7 @@ xor(uint8_t *dst, const uint8_t *src, size_t size)
 
 void
 pkcs5v2_genkey(uint8_t *key, unsigned keylen, const uint8_t *salt,
-    size_t saltsize, const char *passphrase, u_int iterations)
+    size_t saltsize, const char passphrase[], u_int iterations)
 {
 	uint8_t md[SHA512_MDLEN], saltcount[saltsize + sizeof(uint32_t)];
 	uint8_t *counter, *keyp;
@@ -97,7 +97,7 @@ static int
 pkcs5v2_probe(int iterations)
 {
 	uint8_t	key[G_ELI_USERKEYLEN], salt[G_ELI_SALTLEN];
-	uint8_t passphrase[] = "passphrase";
+	const char passphrase[] = "passphrase";
 	struct rusage start, end;
 	int usecs;
 
diff --git a/sys/geom/eli/pkcs5v2.h b/sys/geom/eli/pkcs5v2.h
index da812e98c961..d271c3214536 100644
--- a/sys/geom/eli/pkcs5v2.h
+++ b/sys/geom/eli/pkcs5v2.h
@@ -31,7 +31,7 @@
 #ifndef _PKCS5V2_H_
 #define	_PKCS5V2_H_
 void pkcs5v2_genkey(uint8_t *key, unsigned keylen, const uint8_t *salt,
-    size_t saltsize, const char *passphrase, u_int iterations);
+    size_t saltsize, const char passphrase[], u_int iterations);
 #ifndef _KERNEL
 int pkcs5v2_calculate(int usecs);
 #endif