[CRYPTO] skcipher: Create default givcipher instances

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / crypto / ablkcipher.c

diff --git a/crypto/ablkcipher.c b/crypto/ablkcipher.c
index 092d9659b86149b2ce6d7cb7da43d6a5505e08f5..d1df528c8fa347110dd40018277454c5bf983be0 100644 (file)
--- a/crypto/ablkcipher.c
+++ b/crypto/ablkcipher.c
@@ -18,6 +18,8 @@
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
+#include <linux/rtnetlink.h>
+#include <linux/sched.h>
 #include <linux/slab.h>
 #include <linux/seq_file.h>
 
@@ -68,6 +70,16 @@ static unsigned int crypto_ablkcipher_ctxsize(struct crypto_alg *alg, u32 type,
        return alg->cra_ctxsize;
 }
 
+int skcipher_null_givencrypt(struct skcipher_givcrypt_request *req)
+{
+       return crypto_ablkcipher_encrypt(&req->creq);
+}
+
+int skcipher_null_givdecrypt(struct skcipher_givcrypt_request *req)
+{
+       return crypto_ablkcipher_decrypt(&req->creq);
+}
+
 static int crypto_init_ablkcipher_ops(struct crypto_tfm *tfm, u32 type,
                                      u32 mask)
 {
@@ -80,6 +92,10 @@ static int crypto_init_ablkcipher_ops(struct crypto_tfm *tfm, u32 type,
        crt->setkey = setkey;
        crt->encrypt = alg->encrypt;
        crt->decrypt = alg->decrypt;
+       if (!alg->ivsize) {
+               crt->givencrypt = skcipher_null_givencrypt;
+               crt->givdecrypt = skcipher_null_givdecrypt;
+       }
        crt->base = __crypto_ablkcipher_cast(tfm);
        crt->ivsize = alg->ivsize;
 
@@ -163,6 +179,108 @@ const char *crypto_default_geniv(const struct crypto_alg *alg)
        return alg->cra_flags & CRYPTO_ALG_ASYNC ? "eseqiv" : "chainiv";
 }
 
+static int crypto_givcipher_default(struct crypto_alg *alg, u32 type, u32 mask)
+{
+       struct rtattr *tb[3];
+       struct {
+               struct rtattr attr;
+               struct crypto_attr_type data;
+       } ptype;
+       struct {
+               struct rtattr attr;
+               struct crypto_attr_alg data;
+       } palg;
+       struct crypto_template *tmpl;
+       struct crypto_instance *inst;
+       struct crypto_alg *larval;
+       const char *geniv;
+       int err;
+
+       larval = crypto_larval_lookup(alg->cra_driver_name,
+                                     CRYPTO_ALG_TYPE_GIVCIPHER,
+                                     CRYPTO_ALG_TYPE_MASK);
+       err = PTR_ERR(larval);
+       if (IS_ERR(larval))
+               goto out;
+
+       err = -EAGAIN;
+       if (!crypto_is_larval(larval))
+               goto drop_larval;
+
+       ptype.attr.rta_len = sizeof(ptype);
+       ptype.attr.rta_type = CRYPTOA_TYPE;
+       ptype.data.type = type | CRYPTO_ALG_GENIV;
+       /* GENIV tells the template that we're making a default geniv. */
+       ptype.data.mask = mask | CRYPTO_ALG_GENIV;
+       tb[0] = &ptype.attr;
+
+       palg.attr.rta_len = sizeof(palg);
+       palg.attr.rta_type = CRYPTOA_ALG;
+       /* Must use the exact name to locate ourselves. */
+       memcpy(palg.data.name, alg->cra_driver_name, CRYPTO_MAX_ALG_NAME);
+       tb[1] = &palg.attr;
+
+       tb[2] = NULL;
+
+       if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
+           CRYPTO_ALG_TYPE_BLKCIPHER)
+               geniv = alg->cra_blkcipher.geniv;
+       else
+               geniv = alg->cra_ablkcipher.geniv;
+
+       if (!geniv)
+               geniv = crypto_default_geniv(alg);
+
+       tmpl = crypto_lookup_template(geniv);
+       err = -ENOENT;
+       if (!tmpl)
+               goto kill_larval;
+
+       inst = tmpl->alloc(tb);
+       err = PTR_ERR(inst);
+       if (IS_ERR(inst))
+               goto put_tmpl;
+
+       if ((err = crypto_register_instance(tmpl, inst))) {
+               tmpl->free(inst);
+               goto put_tmpl;
+       }
+
+       /* Redo the lookup to use the instance we just registered. */
+       err = -EAGAIN;
+
+put_tmpl:
+       crypto_tmpl_put(tmpl);
+kill_larval:
+       crypto_larval_kill(larval);
+drop_larval:
+       crypto_mod_put(larval);
+out:
+       crypto_mod_put(alg);
+       return err;
+}
+
+static struct crypto_alg *crypto_lookup_skcipher(const char *name, u32 type,
+                                                u32 mask)
+{
+       struct crypto_alg *alg;
+
+       alg = crypto_alg_mod_lookup(name, type, mask);
+       if (IS_ERR(alg))
+               return alg;
+
+       if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
+           CRYPTO_ALG_TYPE_GIVCIPHER)
+               return alg;
+
+       if (!((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
+             CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize :
+                                         alg->cra_ablkcipher.ivsize))
+               return alg;
+
+       return ERR_PTR(crypto_givcipher_default(alg, type, mask));
+}
+
 int crypto_grab_skcipher(struct crypto_skcipher_spawn *spawn, const char *name,
                         u32 type, u32 mask)
 {
@@ -172,7 +290,7 @@ int crypto_grab_skcipher(struct crypto_skcipher_spawn *spawn, const char *name,
        type = crypto_skcipher_type(type);
        mask = crypto_skcipher_mask(mask);
 
-       alg = crypto_alg_mod_lookup(name, type, mask);
+       alg = crypto_lookup_skcipher(name, type, mask);
        if (IS_ERR(alg))
                return PTR_ERR(alg);
 
@@ -182,5 +300,43 @@ int crypto_grab_skcipher(struct crypto_skcipher_spawn *spawn, const char *name,
 }
 EXPORT_SYMBOL_GPL(crypto_grab_skcipher);
 
+struct crypto_ablkcipher *crypto_alloc_ablkcipher(const char *alg_name,
+                                                 u32 type, u32 mask)
+{
+       struct crypto_tfm *tfm;
+       int err;
+
+       type = crypto_skcipher_type(type);
+       mask = crypto_skcipher_mask(mask);
+
+       for (;;) {
+               struct crypto_alg *alg;
+
+               alg = crypto_lookup_skcipher(alg_name, type, mask);
+               if (IS_ERR(alg)) {
+                       err = PTR_ERR(alg);
+                       goto err;
+               }
+
+               tfm = __crypto_alloc_tfm(alg, type, mask);
+               if (!IS_ERR(tfm))
+                       return __crypto_ablkcipher_cast(tfm);
+
+               crypto_mod_put(alg);
+               err = PTR_ERR(tfm);
+
+err:
+               if (err != -EAGAIN)
+                       break;
+               if (signal_pending(current)) {
+                       err = -EINTR;
+                       break;
+               }
+       }
+
+       return ERR_PTR(err);
+}
+EXPORT_SYMBOL_GPL(crypto_alloc_ablkcipher);
+
 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("Asynchronous block chaining cipher type");