3 files changed, 157 insertions, 9 deletions

diff --git a/crypto/aead.c b/crypto/aead.c
index 9f7aca891926..f5b1add31976 100644
--- a/crypto/aead.c
+++ b/crypto/aead.c
@@ -17,6 +17,7 @@
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
+#include <linux/rtnetlink.h>
 #include <linux/slab.h>
 #include <linux/seq_file.h>
 
@@ -328,5 +329,157 @@ void aead_geniv_exit(struct crypto_tfm *tfm)
 }
 EXPORT_SYMBOL_GPL(aead_geniv_exit);
 
+static int crypto_nivaead_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_AEAD | CRYPTO_ALG_GENIV,
+                                      CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_GENIV);
+        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;
+
+        geniv = alg->cra_aead.geniv;
+
+        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_aead(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_type == &crypto_aead_type)
+                return alg;
+
+        if (!alg->cra_aead.ivsize)
+                return alg;
+
+        return ERR_PTR(crypto_nivaead_default(alg, type, mask));
+}
+
+int crypto_grab_aead(struct crypto_aead_spawn *spawn, const char *name,
+                     u32 type, u32 mask)
+{
+        struct crypto_alg *alg;
+        int err;
+
+        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;
+
+        alg = crypto_lookup_aead(name, type, mask);
+        if (IS_ERR(alg))
+                return PTR_ERR(alg);
+
+        err = crypto_init_spawn(&spawn->base, alg, spawn->base.inst, mask);
+        crypto_mod_put(alg);
+        return err;
+}
+EXPORT_SYMBOL_GPL(crypto_grab_aead);
+
+struct crypto_aead *crypto_alloc_aead(const char *alg_name, u32 type, u32 mask)
+{
+        struct crypto_tfm *tfm;
+        int err;
+
+        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 (;;) {
+                struct crypto_alg *alg;
+
+                alg = crypto_lookup_aead(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_aead_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_aead);
+
 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("Authenticated Encryption with Associated Data (AEAD)");
diff --git a/include/crypto/internal/aead.h b/include/crypto/internal/aead.h
index eb4eee7a7804..d838c945575a 100644
--- a/include/crypto/internal/aead.h
+++ b/include/crypto/internal/aead.h
@@ -31,6 +31,9 @@ static inline void crypto_set_aead_spawn(
         crypto_set_spawn(&spawn->base, inst);
 }
 
+int crypto_grab_aead(struct crypto_aead_spawn *spawn, const char *name,
+                     u32 type, u32 mask);
+
 static inline void crypto_drop_aead(struct crypto_aead_spawn *spawn)
 {
         crypto_drop_spawn(&spawn->base);
diff --git a/include/linux/crypto.h b/include/linux/crypto.h
index 639385a9672d..0aba10460201 100644
--- a/include/linux/crypto.h
+++ b/include/linux/crypto.h
@@ -723,15 +723,7 @@ static inline struct crypto_aead *__crypto_aead_cast(struct crypto_tfm *tfm)
         return (struct crypto_aead *)tfm;
 }
 
-static inline struct crypto_aead *crypto_alloc_aead(const char *alg_name,
-                                                    u32 type, u32 mask)
-{
-        type &= ~CRYPTO_ALG_TYPE_MASK;
-        type |= CRYPTO_ALG_TYPE_AEAD;
-        mask |= CRYPTO_ALG_TYPE_MASK;
-
-        return __crypto_aead_cast(crypto_alloc_base(alg_name, type, mask));
-}
+struct crypto_aead *crypto_alloc_aead(const char *alg_name, u32 type, u32 mask);
 
 static inline struct crypto_tfm *crypto_aead_tfm(struct crypto_aead *tfm)
 {