s390/crypto: Introduce function for tokenize clearkeys

Move the conversion of a clearkey blob to token into a separate
function.

The functionality of the paes module is not affected by this commit.

Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

diff --git a/arch/s390/crypto/paes_s390.c b/arch/s390/crypto/paes_s390.c
index 3daaa6e60ba11d1c8ea1456605429094b540463c..865336032377343d6b5b5166c33449444037a970 100644 (file)
--- a/arch/s390/crypto/paes_s390.c
+++ b/arch/s390/crypto/paes_s390.c
@@ -62,31 +62,43 @@ struct key_blob {
        unsigned int keylen;
 };
 
-static inline int _key_to_kb(struct key_blob *kb,
-                            const u8 *key,
-                            unsigned int keylen)
+/*
+ * make_clrkey_token() - wrap the raw key ck with pkey clearkey token
+ * information.
+ * @returns the size of the clearkey token
+ */
+static inline u32 make_clrkey_token(const u8 *ck, size_t cklen, u8 *dest)
 {
-       struct clearkey_header {
+       struct clrkey_token {
                u8  type;
                u8  res0[3];
                u8  version;
                u8  res1[3];
                u32 keytype;
                u32 len;
-       } __packed * h;
+               u8 key[];
+       } __packed *token = (struct clrkey_token *)dest;
+
+       token->type = 0x00;
+       token->version = 0x02;
+       token->keytype = (cklen - 8) >> 3;
+       token->len = cklen;
+       memcpy(token->key, ck, cklen);
 
+       return sizeof(*token) + cklen;
+}
+
+static inline int _key_to_kb(struct key_blob *kb,
+                            const u8 *key,
+                            unsigned int keylen)
+{
        switch (keylen) {
        case 16:
        case 24:
        case 32:
                /* clear key value, prepare pkey clear key token in keybuf */
                memset(kb->keybuf, 0, sizeof(kb->keybuf));
-               h = (struct clearkey_header *) kb->keybuf;
-               h->version = 0x02; /* TOKVER_CLEAR_KEY */
-               h->keytype = (keylen - 8) >> 3;
-               h->len = keylen;
-               memcpy(kb->keybuf + sizeof(*h), key, keylen);
-               kb->keylen = sizeof(*h) + keylen;
+               kb->keylen = make_clrkey_token(key, keylen, kb->keybuf);
                kb->key = kb->keybuf;
                break;
        default: