diff --git a/sys/geom/eli/pkcs5v2.c b/sys/geom/eli/pkcs5v2.c
index 546f1d64af83..c4cecf4782ab 100644
--- a/sys/geom/eli/pkcs5v2.c
+++ b/sys/geom/eli/pkcs5v2.c
@@ -1,128 +1,137 @@
 /*-
  * SPDX-License-Identifier: BSD-2-Clause
  *
  * Copyright (c) 2005 Pawel Jakub Dawidek <pjd@FreeBSD.org>
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
 
 #include <sys/param.h>
 #ifdef _KERNEL
 #include <sys/systm.h>
 #include <sys/kernel.h>
 #else
 #include <sys/resource.h>
 #include <stdint.h>
 #include <strings.h>
 #endif
 
 #include <geom/eli/g_eli.h>
 #include <geom/eli/pkcs5v2.h>
 
 static __inline void
 xor(uint8_t *dst, const uint8_t *src, size_t size)
 {
 
 	for (; size > 0; size--)
 		*dst++ ^= *src++;
 }
 
 void
 pkcs5v2_genkey(uint8_t *key, unsigned keylen, const uint8_t *salt,
     size_t saltsize, const char *passphrase, u_int iterations)
 {
+
+	pkcs5v2_genkey_raw(key, keylen, salt, saltsize, passphrase,
+	    strlen(passphrase), iterations);
+}
+
+void
+pkcs5v2_genkey_raw(uint8_t *key, unsigned keylen, const uint8_t *salt,
+    size_t saltsize, const uint8_t *passphrase, size_t passlen,
+    u_int iterations)
+{
 	uint8_t md[SHA512_MDLEN], saltcount[saltsize + sizeof(uint32_t)];
 	uint8_t *counter, *keyp;
-	u_int i, bsize, passlen;
+	u_int i, bsize;
 	uint32_t count;
 	struct hmac_ctx startpoint, ctx;
 
-	passlen = strlen(passphrase);
 	bzero(key, keylen);
 	bcopy(salt, saltcount, saltsize);
 	counter = saltcount + saltsize;
 
 	keyp = key;
 	for (count = 1; keylen > 0; count++, keylen -= bsize, keyp += bsize) {
 		bsize = MIN(keylen, sizeof(md));
 
 		be32enc(counter, count);
 
 		g_eli_crypto_hmac_init(&startpoint, passphrase, passlen);
 		ctx = startpoint;
 		g_eli_crypto_hmac_update(&ctx, saltcount, sizeof(saltcount));
 		g_eli_crypto_hmac_final(&ctx, md, sizeof(md));
 		xor(keyp, md, bsize);
 
 		for(i = 1; i < iterations; i++) {
 			ctx = startpoint;
 			g_eli_crypto_hmac_update(&ctx, md, sizeof(md));
 			g_eli_crypto_hmac_final(&ctx, md, sizeof(md));
 			xor(keyp, md, bsize);
 		}
 	}
 	explicit_bzero(&startpoint, sizeof(startpoint));
 	explicit_bzero(&ctx, sizeof(ctx));
 }
 
 #ifndef _KERNEL
 #ifndef _STANDALONE
 /*
  * Return the number of microseconds needed for 'interations' iterations.
  */
 static int
 pkcs5v2_probe(int iterations)
 {
 	uint8_t	key[G_ELI_USERKEYLEN], salt[G_ELI_SALTLEN];
 	const char passphrase[] = "passphrase";
 	struct rusage start, end;
 	int usecs;
 
 	getrusage(RUSAGE_SELF, &start);
 	pkcs5v2_genkey(key, sizeof(key), salt, sizeof(salt), passphrase,
 	    iterations);
 	getrusage(RUSAGE_SELF, &end);
 
 	usecs = end.ru_utime.tv_sec - start.ru_utime.tv_sec;
 	usecs *= 1000000;
 	usecs += end.ru_utime.tv_usec - start.ru_utime.tv_usec;
 	return (usecs);
 }
 
 /*
  * Return the number of iterations which takes 'usecs' microseconds.
  */
 int
 pkcs5v2_calculate(int usecs)
 {
 	int iterations, v;
 
 	for (iterations = 1; ; iterations <<= 1) {
 		v = pkcs5v2_probe(iterations);
 		if (v > 2000000)
 			break;
 	}
 	return (((intmax_t)iterations * (intmax_t)usecs) / v);
 }
 #endif	/* !_STANDALONE */
 #endif	/* !_KERNEL */
diff --git a/sys/geom/eli/pkcs5v2.h b/sys/geom/eli/pkcs5v2.h
index f271f17a68c1..02e3fac02fe7 100644
--- a/sys/geom/eli/pkcs5v2.h
+++ b/sys/geom/eli/pkcs5v2.h
@@ -1,36 +1,39 @@
 /*-
  * SPDX-License-Identifier: BSD-2-Clause
  *
  * Copyright (c) 2005 Pawel Jakub Dawidek <pjd@FreeBSD.org>
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
 
 #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);
+void pkcs5v2_genkey_raw(uint8_t *key, unsigned keylen, const uint8_t *salt,
+    size_t saltsize, const uint8_t *passphrase, size_t passlen,
+    u_int iterations);
 #ifndef _KERNEL
 int pkcs5v2_calculate(int usecs);
 #endif
 #endif	/* !_PKCS5V2_H_ */