crypto: user - Fix lookup of algorithms with IV generator
Steffen Klassert [Thu, 29 Mar 2012 07:03:47 +0000 (09:03 +0200)]
We lookup algorithms with crypto_alg_mod_lookup() when instantiating via
crypto_add_alg(). However, algorithms that are wrapped by an IV genearator
(e.g. aead or genicv type algorithms) need special care. The userspace
process hangs until it gets a timeout when we use crypto_alg_mod_lookup()
to lookup these algorithms. So export the lookup functions for these
algorithms and use them in crypto_add_alg().

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto/ablkcipher.c
crypto/aead.c
crypto/crypto_user.c
include/crypto/internal/aead.h
include/crypto/internal/skcipher.h

index a0f768c..8d3a056 100644 (file)
@@ -613,8 +613,7 @@ out:
        return err;
 }
 
-static struct crypto_alg *crypto_lookup_skcipher(const char *name, u32 type,
-                                                u32 mask)
+struct crypto_alg *crypto_lookup_skcipher(const char *name, u32 type, u32 mask)
 {
        struct crypto_alg *alg;
 
@@ -652,6 +651,7 @@ static struct crypto_alg *crypto_lookup_skcipher(const char *name, u32 type,
 
        return ERR_PTR(crypto_givcipher_default(alg, type, mask));
 }
+EXPORT_SYMBOL_GPL(crypto_lookup_skcipher);
 
 int crypto_grab_skcipher(struct crypto_skcipher_spawn *spawn, const char *name,
                         u32 type, u32 mask)
index 04add3d..e4cb351 100644 (file)
@@ -470,8 +470,7 @@ out:
        return err;
 }
 
-static struct crypto_alg *crypto_lookup_aead(const char *name, u32 type,
-                                            u32 mask)
+struct crypto_alg *crypto_lookup_aead(const char *name, u32 type, u32 mask)
 {
        struct crypto_alg *alg;
 
@@ -503,6 +502,7 @@ static struct crypto_alg *crypto_lookup_aead(const char *name, u32 type,
 
        return ERR_PTR(crypto_nivaead_default(alg, type, mask));
 }
+EXPORT_SYMBOL_GPL(crypto_lookup_aead);
 
 int crypto_grab_aead(struct crypto_aead_spawn *spawn, const char *name,
                     u32 type, u32 mask)
index f76e42b..e91c161 100644 (file)
 #include <linux/module.h>
 #include <linux/crypto.h>
 #include <linux/cryptouser.h>
+#include <linux/sched.h>
 #include <net/netlink.h>
 #include <linux/security.h>
 #include <net/net_namespace.h>
+#include <crypto/internal/aead.h>
+#include <crypto/internal/skcipher.h>
+
 #include "internal.h"
 
 DEFINE_MUTEX(crypto_cfg_mutex);
@@ -301,6 +305,60 @@ static int crypto_del_alg(struct sk_buff *skb, struct nlmsghdr *nlh,
        return crypto_unregister_instance(alg);
 }
 
+static struct crypto_alg *crypto_user_skcipher_alg(const char *name, u32 type,
+                                                  u32 mask)
+{
+       int err;
+       struct crypto_alg *alg;
+
+       type = crypto_skcipher_type(type);
+       mask = crypto_skcipher_mask(mask);
+
+       for (;;) {
+               alg = crypto_lookup_skcipher(name,  type, mask);
+               if (!IS_ERR(alg))
+                       return alg;
+
+               err = PTR_ERR(alg);
+               if (err != -EAGAIN)
+                       break;
+               if (signal_pending(current)) {
+                       err = -EINTR;
+                       break;
+               }
+       }
+
+       return ERR_PTR(err);
+}
+
+static struct crypto_alg *crypto_user_aead_alg(const char *name, u32 type,
+                                              u32 mask)
+{
+       int err;
+       struct crypto_alg *alg;
+
+       type &= ~(CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_GENIV);
+       type |= CRYPTO_ALG_TYPE_AEAD;
+       mask &= ~(CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_GENIV);
+       mask |= CRYPTO_ALG_TYPE_MASK;
+
+       for (;;) {
+               alg = crypto_lookup_aead(name,  type, mask);
+               if (!IS_ERR(alg))
+                       return alg;
+
+               err = PTR_ERR(alg);
+               if (err != -EAGAIN)
+                       break;
+               if (signal_pending(current)) {
+                       err = -EINTR;
+                       break;
+               }
+       }
+
+       return ERR_PTR(err);
+}
+
 static int crypto_add_alg(struct sk_buff *skb, struct nlmsghdr *nlh,
                          struct nlattr **attrs)
 {
@@ -325,7 +383,19 @@ static int crypto_add_alg(struct sk_buff *skb, struct nlmsghdr *nlh,
        else
                name = p->cru_name;
 
-       alg = crypto_alg_mod_lookup(name, p->cru_type, p->cru_mask);
+       switch (p->cru_type & p->cru_mask & CRYPTO_ALG_TYPE_MASK) {
+       case CRYPTO_ALG_TYPE_AEAD:
+               alg = crypto_user_aead_alg(name, p->cru_type, p->cru_mask);
+               break;
+       case CRYPTO_ALG_TYPE_GIVCIPHER:
+       case CRYPTO_ALG_TYPE_BLKCIPHER:
+       case CRYPTO_ALG_TYPE_ABLKCIPHER:
+               alg = crypto_user_skcipher_alg(name, p->cru_type, p->cru_mask);
+               break;
+       default:
+               alg = crypto_alg_mod_lookup(name, p->cru_type, p->cru_mask);
+       }
+
        if (IS_ERR(alg))
                return PTR_ERR(alg);
 
index d838c94..2eba340 100644 (file)
@@ -31,6 +31,8 @@ static inline void crypto_set_aead_spawn(
        crypto_set_spawn(&spawn->base, inst);
 }
 
+struct crypto_alg *crypto_lookup_aead(const char *name, u32 type, u32 mask);
+
 int crypto_grab_aead(struct crypto_aead_spawn *spawn, const char *name,
                     u32 type, u32 mask);
 
index 3a748a6..06e8b32 100644 (file)
@@ -34,6 +34,8 @@ static inline void crypto_set_skcipher_spawn(
 int crypto_grab_skcipher(struct crypto_skcipher_spawn *spawn, const char *name,
                         u32 type, u32 mask);
 
+struct crypto_alg *crypto_lookup_skcipher(const char *name, u32 type, u32 mask);
+
 static inline void crypto_drop_skcipher(struct crypto_skcipher_spawn *spawn)
 {
        crypto_drop_spawn(&spawn->base);