mac80211: aead api to reduce redundancy

Currently, the aes_ccm.c and aes_gcm.c are almost line by line copy of
each other. This patch reduce code redundancy by moving the code in these
two files to crypto/aead_api.c to make it a higher level aead api. The
file aes_ccm.c and aes_gcm.c are removed and all the functions there are
now implemented in their headers using the newly added aead api.

Signed-off-by: Xiang Gao <qasdfgtyuiop@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

7 files changed, 111 insertions, 152 deletions

diff --git a/net/mac80211/Makefile b/net/mac80211/Makefile
index 282912245938..80f25ff2f24b 100644
--- a/net/mac80211/Makefile
+++ b/net/mac80211/Makefile
@@ -6,6 +6,7 @@ mac80211-y := \
         driver-ops.o \
         sta_info.o \
         wep.o \
+        aead_api.o \
         wpa.o \
         scan.o offchannel.o \
         ht.o agg-tx.o agg-rx.o \
@@ -15,8 +16,6 @@ mac80211-y := \
         rate.o \
         michael.o \
         tkip.o \
-        aes_ccm.o \
-        aes_gcm.o \
         aes_cmac.o \
         aes_gmac.o \
         fils_aead.o \
diff --git a/net/mac80211/aes_ccm.c b/net/mac80211/aead_api.c
index a4e0d59a40dd..347f13953b2c 100644
--- a/net/mac80211/aes_ccm.c
+++ b/net/mac80211/aead_api.c
@@ -1,6 +1,7 @@
 /*
  * Copyright 2003-2004, Instant802 Networks, Inc.
  * Copyright 2005-2006, Devicescape Software, Inc.
+ * Copyright 2014-2015, Qualcomm Atheros, Inc.
  *
  * Rewrite: Copyright (C) 2013 Linaro Ltd <ard.biesheuvel@linaro.org>
  *
@@ -12,30 +13,29 @@
 #include <linux/kernel.h>
 #include <linux/types.h>
 #include <linux/err.h>
+#include <linux/scatterlist.h>
 #include <crypto/aead.h>
 
-#include <net/mac80211.h>
-#include "key.h"
-#include "aes_ccm.h"
+#include "aead_api.h"
 
-int ieee80211_aes_ccm_encrypt(struct crypto_aead *tfm, u8 *b_0, u8 *aad,
-                              u8 *data, size_t data_len, u8 *mic,
-                              size_t mic_len)
+int aead_encrypt(struct crypto_aead *tfm, u8 *b_0, u8 *aad, size_t aad_len,
+                 u8 *data, size_t data_len, u8 *mic)
 {
+        size_t mic_len = tfm->authsize;
         struct scatterlist sg[3];
         struct aead_request *aead_req;
         int reqsize = sizeof(*aead_req) + crypto_aead_reqsize(tfm);
         u8 *__aad;
 
-        aead_req = kzalloc(reqsize + CCM_AAD_LEN, GFP_ATOMIC);
+        aead_req = kzalloc(reqsize + aad_len, GFP_ATOMIC);
         if (!aead_req)
                 return -ENOMEM;
 
         __aad = (u8 *)aead_req + reqsize;
-        memcpy(__aad, aad, CCM_AAD_LEN);
+        memcpy(__aad, aad, aad_len);
 
         sg_init_table(sg, 3);
-        sg_set_buf(&sg[0], &__aad[2], be16_to_cpup((__be16 *)__aad));
+        sg_set_buf(&sg[0], __aad, aad_len);
         sg_set_buf(&sg[1], data, data_len);
         sg_set_buf(&sg[2], mic, mic_len);
 
@@ -49,10 +49,10 @@ int ieee80211_aes_ccm_encrypt(struct crypto_aead *tfm, u8 *b_0, u8 *aad,
         return 0;
 }
 
-int ieee80211_aes_ccm_decrypt(struct crypto_aead *tfm, u8 *b_0, u8 *aad,
-                              u8 *data, size_t data_len, u8 *mic,
-                              size_t mic_len)
+int aead_decrypt(struct crypto_aead *tfm, u8 *b_0, u8 *aad, size_t aad_len,
+                 u8 *data, size_t data_len, u8 *mic)
 {
+        size_t mic_len = tfm->authsize;
         struct scatterlist sg[3];
         struct aead_request *aead_req;
         int reqsize = sizeof(*aead_req) + crypto_aead_reqsize(tfm);
@@ -62,15 +62,15 @@ int ieee80211_aes_ccm_decrypt(struct crypto_aead *tfm, u8 *b_0, u8 *aad,
         if (data_len == 0)
                 return -EINVAL;
 
-        aead_req = kzalloc(reqsize + CCM_AAD_LEN, GFP_ATOMIC);
+        aead_req = kzalloc(reqsize + aad_len, GFP_ATOMIC);
         if (!aead_req)
                 return -ENOMEM;
 
         __aad = (u8 *)aead_req + reqsize;
-        memcpy(__aad, aad, CCM_AAD_LEN);
+        memcpy(__aad, aad, aad_len);
 
         sg_init_table(sg, 3);
-        sg_set_buf(&sg[0], &__aad[2], be16_to_cpup((__be16 *)__aad));
+        sg_set_buf(&sg[0], __aad, aad_len);
         sg_set_buf(&sg[1], data, data_len);
         sg_set_buf(&sg[2], mic, mic_len);
 
@@ -84,14 +84,14 @@ int ieee80211_aes_ccm_decrypt(struct crypto_aead *tfm, u8 *b_0, u8 *aad,
         return err;
 }
 
-struct crypto_aead *ieee80211_aes_key_setup_encrypt(const u8 key[],
-                                                    size_t key_len,
-                                                    size_t mic_len)
+struct crypto_aead *
+aead_key_setup_encrypt(const char *alg, const u8 key[],
+                       size_t key_len, size_t mic_len)
 {
         struct crypto_aead *tfm;
         int err;
 
-        tfm = crypto_alloc_aead("ccm(aes)", 0, CRYPTO_ALG_ASYNC);
+        tfm = crypto_alloc_aead(alg, 0, CRYPTO_ALG_ASYNC);
         if (IS_ERR(tfm))
                 return tfm;
 
@@ -109,7 +109,7 @@ free_aead:
         return ERR_PTR(err);
 }
 
-void ieee80211_aes_key_free(struct crypto_aead *tfm)
+void aead_key_free(struct crypto_aead *tfm)
 {
         crypto_free_aead(tfm);
 }
diff --git a/net/mac80211/aead_api.h b/net/mac80211/aead_api.h
new file mode 100644
index 000000000000..5e39ea843bbf
--- /dev/null
+++ b/net/mac80211/aead_api.h
@@ -0,0 +1,27 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _AEAD_API_H
+#define _AEAD_API_H
+
+#include <crypto/aead.h>
+#include <linux/crypto.h>
+
+struct crypto_aead *
+aead_key_setup_encrypt(const char *alg, const u8 key[],
+                       size_t key_len, size_t mic_len);
+
+int aead_encrypt(struct crypto_aead *tfm, u8 *b_0, u8 *aad,
+                 size_t aad_len, u8 *data,
+                 size_t data_len, u8 *mic);
+
+int aead_decrypt(struct crypto_aead *tfm, u8 *b_0, u8 *aad,
+                 size_t aad_len, u8 *data,
+                 size_t data_len, u8 *mic);
+
+void aead_key_free(struct crypto_aead *tfm);
+
+#endif /* _AEAD_API_H */
diff --git a/net/mac80211/aes_ccm.h b/net/mac80211/aes_ccm.h
index fcd3254c5cf0..e9b7ca0bde5b 100644
--- a/net/mac80211/aes_ccm.h
+++ b/net/mac80211/aes_ccm.h
@@ -10,19 +10,39 @@
 #ifndef AES_CCM_H
 #define AES_CCM_H
 
-#include <linux/crypto.h>
+#include "aead_api.h"
 
 #define CCM_AAD_LEN     32
 
-struct crypto_aead *ieee80211_aes_key_setup_encrypt(const u8 key[],
-                                                    size_t key_len,
-                                                    size_t mic_len);
-int ieee80211_aes_ccm_encrypt(struct crypto_aead *tfm, u8 *b_0, u8 *aad,
-                              u8 *data, size_t data_len, u8 *mic,
-                              size_t mic_len);
-int ieee80211_aes_ccm_decrypt(struct crypto_aead *tfm, u8 *b_0, u8 *aad,
-                              u8 *data, size_t data_len, u8 *mic,
-                              size_t mic_len);
-void ieee80211_aes_key_free(struct crypto_aead *tfm);
+static inline struct crypto_aead *
+ieee80211_aes_key_setup_encrypt(const u8 key[], size_t key_len, size_t mic_len)
+{
+        return aead_key_setup_encrypt("ccm(aes)", key, key_len, mic_len);
+}
+
+static inline int
+ieee80211_aes_ccm_encrypt(struct crypto_aead *tfm,
+                          u8 *b_0, u8 *aad, u8 *data,
+                          size_t data_len, u8 *mic)
+{
+        return aead_encrypt(tfm, b_0, aad + 2,
+                            be16_to_cpup((__be16 *)aad),
+                            data, data_len, mic);
+}
+
+static inline int
+ieee80211_aes_ccm_decrypt(struct crypto_aead *tfm,
+                          u8 *b_0, u8 *aad, u8 *data,
+                          size_t data_len, u8 *mic)
+{
+        return aead_decrypt(tfm, b_0, aad + 2,
+                            be16_to_cpup((__be16 *)aad),
+                            data, data_len, mic);
+}
+
+static inline void ieee80211_aes_key_free(struct crypto_aead *tfm)
+{
+        return aead_key_free(tfm);
+}
 
 #endif /* AES_CCM_H */
diff --git a/net/mac80211/aes_gcm.c b/net/mac80211/aes_gcm.c
deleted file mode 100644
index 8a4397cc1b08..000000000000
--- a/net/mac80211/aes_gcm.c
+++ /dev/null
@@ -1,109 +0,0 @@
-/*
- * Copyright 2014-2015, Qualcomm Atheros, Inc.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- */
-
-#include <linux/kernel.h>
-#include <linux/types.h>
-#include <linux/err.h>
-#include <crypto/aead.h>
-
-#include <net/mac80211.h>
-#include "key.h"
-#include "aes_gcm.h"
-
-int ieee80211_aes_gcm_encrypt(struct crypto_aead *tfm, u8 *j_0, u8 *aad,
-                              u8 *data, size_t data_len, u8 *mic)
-{
-        struct scatterlist sg[3];
-        struct aead_request *aead_req;
-        int reqsize = sizeof(*aead_req) + crypto_aead_reqsize(tfm);
-        u8 *__aad;
-
-        aead_req = kzalloc(reqsize + GCM_AAD_LEN, GFP_ATOMIC);
-        if (!aead_req)
-                return -ENOMEM;
-
-        __aad = (u8 *)aead_req + reqsize;
-        memcpy(__aad, aad, GCM_AAD_LEN);
-
-        sg_init_table(sg, 3);
-        sg_set_buf(&sg[0], &__aad[2], be16_to_cpup((__be16 *)__aad));
-        sg_set_buf(&sg[1], data, data_len);
-        sg_set_buf(&sg[2], mic, IEEE80211_GCMP_MIC_LEN);
-
-        aead_request_set_tfm(aead_req, tfm);
-        aead_request_set_crypt(aead_req, sg, sg, data_len, j_0);
-        aead_request_set_ad(aead_req, sg[0].length);
-
-        crypto_aead_encrypt(aead_req);
-        kzfree(aead_req);
-        return 0;
-}
-
-int ieee80211_aes_gcm_decrypt(struct crypto_aead *tfm, u8 *j_0, u8 *aad,
-                              u8 *data, size_t data_len, u8 *mic)
-{
-        struct scatterlist sg[3];
-        struct aead_request *aead_req;
-        int reqsize = sizeof(*aead_req) + crypto_aead_reqsize(tfm);
-        u8 *__aad;
-        int err;
-
-        if (data_len == 0)
-                return -EINVAL;
-
-        aead_req = kzalloc(reqsize + GCM_AAD_LEN, GFP_ATOMIC);
-        if (!aead_req)
-                return -ENOMEM;
-
-        __aad = (u8 *)aead_req + reqsize;
-        memcpy(__aad, aad, GCM_AAD_LEN);
-
-        sg_init_table(sg, 3);
-        sg_set_buf(&sg[0], &__aad[2], be16_to_cpup((__be16 *)__aad));
-        sg_set_buf(&sg[1], data, data_len);
-        sg_set_buf(&sg[2], mic, IEEE80211_GCMP_MIC_LEN);
-
-        aead_request_set_tfm(aead_req, tfm);
-        aead_request_set_crypt(aead_req, sg, sg,
-                               data_len + IEEE80211_GCMP_MIC_LEN, j_0);
-        aead_request_set_ad(aead_req, sg[0].length);
-
-        err = crypto_aead_decrypt(aead_req);
-        kzfree(aead_req);
-
-        return err;
-}
-
-struct crypto_aead *ieee80211_aes_gcm_key_setup_encrypt(const u8 key[],
-                                                        size_t key_len)
-{
-        struct crypto_aead *tfm;
-        int err;
-
-        tfm = crypto_alloc_aead("gcm(aes)", 0, CRYPTO_ALG_ASYNC);
-        if (IS_ERR(tfm))
-                return tfm;
-
-        err = crypto_aead_setkey(tfm, key, key_len);
-        if (err)
-                goto free_aead;
-        err = crypto_aead_setauthsize(tfm, IEEE80211_GCMP_MIC_LEN);
-        if (err)
-                goto free_aead;
-
-        return tfm;
-
-free_aead:
-        crypto_free_aead(tfm);
-        return ERR_PTR(err);
-}
-
-void ieee80211_aes_gcm_key_free(struct crypto_aead *tfm)
-{
-        crypto_free_aead(tfm);
-}
diff --git a/net/mac80211/aes_gcm.h b/net/mac80211/aes_gcm.h
index 55aed5352494..d2b096033009 100644
--- a/net/mac80211/aes_gcm.h
+++ b/net/mac80211/aes_gcm.h
@@ -9,16 +9,38 @@
 #ifndef AES_GCM_H
 #define AES_GCM_H
 
-#include <linux/crypto.h>
+#include "aead_api.h"
 
 #define GCM_AAD_LEN     32
 
-int ieee80211_aes_gcm_encrypt(struct crypto_aead *tfm, u8 *j_0, u8 *aad,
-                              u8 *data, size_t data_len, u8 *mic);
-int ieee80211_aes_gcm_decrypt(struct crypto_aead *tfm, u8 *j_0, u8 *aad,
-                              u8 *data, size_t data_len, u8 *mic);
-struct crypto_aead *ieee80211_aes_gcm_key_setup_encrypt(const u8 key[],
-                                                        size_t key_len);
-void ieee80211_aes_gcm_key_free(struct crypto_aead *tfm);
+static inline int ieee80211_aes_gcm_encrypt(struct crypto_aead *tfm,
+                                            u8 *j_0, u8 *aad,  u8 *data,
+                                            size_t data_len, u8 *mic)
+{
+        return aead_encrypt(tfm, j_0, aad + 2,
+                            be16_to_cpup((__be16 *)aad),
+                            data, data_len, mic);
+}
+
+static inline int ieee80211_aes_gcm_decrypt(struct crypto_aead *tfm,
+                                            u8 *j_0, u8 *aad, u8 *data,
+                                            size_t data_len, u8 *mic)
+{
+        return aead_decrypt(tfm, j_0, aad + 2,
+                            be16_to_cpup((__be16 *)aad),
+                            data, data_len, mic);
+}
+
+static inline struct crypto_aead *
+ieee80211_aes_gcm_key_setup_encrypt(const u8 key[], size_t key_len)
+{
+        return aead_key_setup_encrypt("gcm(aes)", key,
+                                      key_len, IEEE80211_GCMP_MIC_LEN);
+}
+
+static inline void ieee80211_aes_gcm_key_free(struct crypto_aead *tfm)
+{
+        return aead_key_free(tfm);
+}
 
 #endif /* AES_GCM_H */
diff --git a/net/mac80211/wpa.c b/net/mac80211/wpa.c
index 0d722ea98a1b..b58722d9de37 100644
--- a/net/mac80211/wpa.c
+++ b/net/mac80211/wpa.c
@@ -464,7 +464,7 @@ static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb,
         pos += IEEE80211_CCMP_HDR_LEN;
         ccmp_special_blocks(skb, pn, b_0, aad);
         return ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, b_0, aad, pos, len,
-                                         skb_put(skb, mic_len), mic_len);
+                                         skb_put(skb, mic_len));
 }
 
 
@@ -543,7 +543,7 @@ ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx,
                                     key->u.ccmp.tfm, b_0, aad,
                                     skb->data + hdrlen + IEEE80211_CCMP_HDR_LEN,
                                     data_len,
-                                    skb->data + skb->len - mic_len, mic_len))
+                                    skb->data + skb->len - mic_len))
                                 return RX_DROP_UNUSABLE;
                 }