diff --git a/lib/crypto_backend/crypto_backend.h b/lib/crypto_backend/crypto_backend.h
index e65e9e27..84839e3a 100644
--- a/lib/crypto_backend/crypto_backend.h
+++ b/lib/crypto_backend/crypto_backend.h
@@ -48,7 +48,7 @@ void crypt_hash_destroy(struct crypt_hash *ctx);
 /* HMAC */
 int crypt_hmac_size(const char *name);
 int crypt_hmac_init(struct crypt_hmac **ctx, const char *name,
-		    const void *buffer, size_t length);
+		    const void *key, size_t key_length);
 int crypt_hmac_write(struct crypt_hmac *ctx, const char *buffer, size_t length);
 int crypt_hmac_final(struct crypt_hmac *ctx, char *buffer, size_t length);
 void crypt_hmac_destroy(struct crypt_hmac *ctx);
diff --git a/lib/crypto_backend/crypto_gcrypt.c b/lib/crypto_backend/crypto_gcrypt.c
index 7d237866..a1ed7f63 100644
--- a/lib/crypto_backend/crypto_gcrypt.c
+++ b/lib/crypto_backend/crypto_gcrypt.c
@@ -239,7 +239,7 @@ int crypt_hmac_size(const char *name)
 }
 
 int crypt_hmac_init(struct crypt_hmac **ctx, const char *name,
-		    const void *buffer, size_t length)
+		    const void *key, size_t key_length)
 {
 	struct crypt_hmac *h;
 	unsigned int flags = GCRY_MD_FLAG_HMAC;
@@ -261,7 +261,7 @@ int crypt_hmac_init(struct crypt_hmac **ctx, const char *name,
 		return -EINVAL;
 	}
 
-	if (gcry_md_setkey(h->hd, buffer, length)) {
+	if (gcry_md_setkey(h->hd, key, key_length)) {
 		gcry_md_close(h->hd);
 		free(h);
 		return -EINVAL;
diff --git a/lib/crypto_backend/crypto_kernel.c b/lib/crypto_backend/crypto_kernel.c
index 99bfad28..777f8da2 100644
--- a/lib/crypto_backend/crypto_kernel.c
+++ b/lib/crypto_backend/crypto_kernel.c
@@ -234,7 +234,7 @@ int crypt_hmac_size(const char *name)
 }
 
 int crypt_hmac_init(struct crypt_hmac **ctx, const char *name,
-		    const void *buffer, size_t length)
+		    const void *key, size_t key_length)
 {
 	struct crypt_hmac *h;
 	struct hash_alg *ha;
@@ -257,7 +257,7 @@ int crypt_hmac_init(struct crypt_hmac **ctx, const char *name,
 	snprintf((char *)sa.salg_name, sizeof(sa.salg_name),
 		 "hmac(%s)", ha->kernel_name);
 
-	if (crypt_kernel_socket_init(&sa, &h->tfmfd, &h->opfd, buffer, length) < 0) {
+	if (crypt_kernel_socket_init(&sa, &h->tfmfd, &h->opfd, key, key_length) < 0) {
 		free(h);
 		return -EINVAL;
 	}
diff --git a/lib/crypto_backend/crypto_nettle.c b/lib/crypto_backend/crypto_nettle.c
index 5d133d6c..9a7406a4 100644
--- a/lib/crypto_backend/crypto_nettle.c
+++ b/lib/crypto_backend/crypto_nettle.c
@@ -215,7 +215,7 @@ int crypt_hmac_size(const char *name)
 }
 
 int crypt_hmac_init(struct crypt_hmac **ctx, const char *name,
-		    const void *buffer, size_t length)
+		    const void *key, size_t key_length)
 {
 	struct crypt_hmac *h;
 
@@ -229,12 +229,12 @@ int crypt_hmac_init(struct crypt_hmac **ctx, const char *name,
 	if (!h->hash)
 		goto bad;
 
-	h->key = malloc(length);
+	h->key = malloc(key_length);
 	if (!h->key)
 		goto bad;
 
-	memcpy(h->key, buffer, length);
-	h->key_length = length;
+	memcpy(h->key, key, key_length);
+	h->key_length = key_length;
 
 	h->hash->init(&h->nettle_ctx);
 	h->hash->hmac_set_key(&h->nettle_ctx, h->key_length, h->key);
diff --git a/lib/crypto_backend/crypto_nss.c b/lib/crypto_backend/crypto_nss.c
index 5287d3a7..9caf241b 100644
--- a/lib/crypto_backend/crypto_nss.c
+++ b/lib/crypto_backend/crypto_nss.c
@@ -194,15 +194,15 @@ int crypt_hmac_size(const char *name)
 }
 
 int crypt_hmac_init(struct crypt_hmac **ctx, const char *name,
-		    const void *buffer, size_t length)
+		    const void *key, size_t key_length)
 {
 	struct crypt_hmac *h;
 	SECItem keyItem;
 	SECItem noParams;
 
 	keyItem.type = siBuffer;
-	keyItem.data = CONST_CAST(unsigned char *)buffer;
-	keyItem.len = (int)length;
+	keyItem.data = CONST_CAST(unsigned char *)key;
+	keyItem.len = (int)key_length;
 
 	noParams.type = siBuffer;
 	noParams.data = 0;
diff --git a/lib/crypto_backend/crypto_openssl.c b/lib/crypto_backend/crypto_openssl.c
index 147db028..4929f828 100644
--- a/lib/crypto_backend/crypto_openssl.c
+++ b/lib/crypto_backend/crypto_openssl.c
@@ -227,7 +227,7 @@ int crypt_hmac_size(const char *name)
 }
 
 int crypt_hmac_init(struct crypt_hmac **ctx, const char *name,
-		    const void *buffer, size_t length)
+		    const void *key, size_t key_length)
 {
 	struct crypt_hmac *h;
 
@@ -248,7 +248,7 @@ int crypt_hmac_init(struct crypt_hmac **ctx, const char *name,
 		return -EINVAL;
 	}
 
-	HMAC_Init_ex(h->md, buffer, length, h->hash_id, NULL);
+	HMAC_Init_ex(h->md, key, key_length, h->hash_id, NULL);
 
 	h->hash_len = EVP_MD_size(h->hash_id);
 	*ctx = h;