diff --git a/src/crypto.c b/src/crypto.c
index eb83c6f0..7428087c 100644
--- a/src/crypto.c
+++ b/src/crypto.c
@@ -268,66 +268,6 @@ int crypto_cipher_tk_bits(enum crypto_cipher cipher)
 	return crypto_cipher_key_len(cipher) * 8;
 }
 
-#define SHA1_MAC_LEN 20
-
-static void F(struct l_checksum *checksum,
-			const char *salt, size_t salt_len,
-			unsigned int iterations, unsigned int count,
-							unsigned char *digest)
-{
-	unsigned char tmp[SHA1_MAC_LEN];
-	unsigned char buf[36];
-	unsigned int i, j;
-
-	memcpy(buf, salt, salt_len);
-	buf[salt_len + 0] = (count >> 24) & 0xff;
-	buf[salt_len + 1] = (count >> 16) & 0xff;
-	buf[salt_len + 2] = (count >> 8) & 0xff;
-	buf[salt_len + 3] = count & 0xff;
-
-	l_checksum_update(checksum, buf, salt_len + 4);
-	l_checksum_get_digest(checksum, tmp, SHA1_MAC_LEN);
-	memcpy(digest, tmp, SHA1_MAC_LEN);
-
-	for (i = 1; i < iterations; i++) {
-		l_checksum_update(checksum, tmp, SHA1_MAC_LEN);
-		l_checksum_get_digest(checksum, tmp, SHA1_MAC_LEN);
-
-		for (j = 0; j < SHA1_MAC_LEN; j++)
-			digest[j] ^= tmp[j];
-	}
-}
-
-bool pbkdf2_sha1(const void *password, size_t password_len,
-			const void *salt, size_t salt_len,
-			unsigned int iterations, void *output, size_t size)
-{
-	struct l_checksum *checksum;
-	unsigned char *ptr = output;
-	unsigned char digest[SHA1_MAC_LEN];
-	unsigned int i;
-
-	checksum = l_checksum_new_hmac(L_CHECKSUM_SHA1, password, password_len);
-	if (!checksum)
-		return false;
-
-	for (i = 1; size > 0; i++) {
-		size_t len;
-
-		F(checksum, salt, salt_len, iterations, i, digest);
-
-		len = size > SHA1_MAC_LEN ? SHA1_MAC_LEN : size;
-		memcpy(ptr, digest, len);
-
-		ptr += len;
-		size -= len;
-	}
-
-	l_checksum_free(checksum);
-
-	return true;
-}
-
 int crypto_psk_from_passphrase(const char *passphrase,
 				const unsigned char *ssid, size_t ssid_len,
 				unsigned char *out_psk)
@@ -370,7 +310,7 @@ int crypto_psk_from_passphrase(const char *passphrase,
 		return -EINVAL;
 	}
 
-	result = pbkdf2_sha1(passphrase, passphrase_len, ssid, ssid_len,
+	result = l_pkcs5_pbkdf2(L_CHECKSUM_SHA1, passphrase, ssid, ssid_len,
 				4096, psk, sizeof(psk));
 	if (!result)
 		return -ENOKEY;
diff --git a/src/crypto.h b/src/crypto.h
index 872c0c36..f170b257 100644
--- a/src/crypto.h
+++ b/src/crypto.h
@@ -72,10 +72,6 @@ bool arc4_skip(const uint8_t *key, size_t key_len, size_t skip,
 int crypto_cipher_key_len(enum crypto_cipher cipher);
 int crypto_cipher_tk_bits(enum crypto_cipher cipher);
 
-bool pbkdf2_sha1(const void *password, size_t password_len,
-			const void *salt, size_t salt_len,
-			unsigned int iterations, void *output, size_t size);
-
 int crypto_psk_from_passphrase(const char *passphrase,
 				const unsigned char *ssid, size_t ssid_len,
 				unsigned char *out_psk);