Prior to this commit, functions rtw_tkip_encrypt23a and rtw_tkip_decrypt23a had
large if blocks which contained the majority of the logic in the functions.

Rework these functions so that if the negated version of the aforementioned if
blocks' conditions are true, we return from the function with _FAIL, as
expected by the calling code.

This lets us remove two levels of indentation from the functions in
question, making them more readable.

Signed-off-by: M. Vefa Bicakci <m....@runbox.com>
---
 drivers/staging/rtl8723au/core/rtw_security.c | 178 +++++++++++++-------------
 1 file changed, 88 insertions(+), 90 deletions(-)

diff --git a/drivers/staging/rtl8723au/core/rtw_security.c 
b/drivers/staging/rtl8723au/core/rtw_security.c
index df1787f20e..f7b1d45981 100644
--- a/drivers/staging/rtl8723au/core/rtw_security.c
+++ b/drivers/staging/rtl8723au/core/rtw_security.c
@@ -618,6 +618,9 @@ int rtw_tkip_encrypt23a(struct rtw_adapter *padapter,
        struct xmit_priv *pxmitpriv = &padapter->xmitpriv;
        int res = _SUCCESS;
 
+       if (pattrib->encrypt != WLAN_CIPHER_SUITE_TKIP)
+               return _FAIL;
+
        if (!pxmitframe->buf_addr)
                return _FAIL;
 
@@ -625,71 +628,66 @@ int rtw_tkip_encrypt23a(struct rtw_adapter *padapter,
 
        pframe = pxmitframe->buf_addr + hw_hdr_offset;
        /* 4 start to encrypt each fragment */
-       if (pattrib->encrypt == WLAN_CIPHER_SUITE_TKIP) {
-               if (pattrib->psta)
-                       stainfo = pattrib->psta;
-               else {
-                       DBG_8723A("%s, call rtw_get_stainfo()\n", __func__);
-                       stainfo = rtw_get_stainfo23a(&padapter->stapriv,
-                                                    &pattrib->ra[0]);
-               }
-
-               if (stainfo != NULL) {
-
-                       if (!(stainfo->state & _FW_LINKED)) {
-                               DBG_8723A("%s, psta->state(0x%x) != 
_FW_LINKED\n", __func__, stainfo->state);
-                               return _FAIL;
-                       }
+       if (pattrib->psta)
+               stainfo = pattrib->psta;
+       else {
+               DBG_8723A("%s, call rtw_get_stainfo()\n", __func__);
+               stainfo = rtw_get_stainfo23a(&padapter->stapriv,
+                                            &pattrib->ra[0]);
+       }
 
-                       RT_TRACE(_module_rtl871x_security_c_, _drv_err_, 
("rtw_tkip_encrypt23a: stainfo!= NULL!!!\n"));
+       if (stainfo == NULL) {
+               RT_TRACE(_module_rtl871x_security_c_, _drv_err_, 
("rtw_tkip_encrypt23a: stainfo == NULL!!!\n"));
+               DBG_8723A("%s, psta == NUL\n", __func__);
+               return _FAIL;
+       }
 
-                       if (is_multicast_ether_addr(pattrib->ra))
-                               prwskey = 
psecuritypriv->dot118021XGrpKey[psecuritypriv->dot118021XGrpKeyid].skey;
-                       else
-                               prwskey = &stainfo->dot118021x_UncstKey.skey[0];
+       if (!(stainfo->state & _FW_LINKED)) {
+               DBG_8723A("%s, psta->state(0x%x) != _FW_LINKED\n", __func__, 
stainfo->state);
+               return _FAIL;
+       }
 
-                       prwskeylen = 16;
+       RT_TRACE(_module_rtl871x_security_c_, _drv_err_, ("rtw_tkip_encrypt23a: 
stainfo!= NULL!!!\n"));
 
-                       for (curfragnum = 0; curfragnum < pattrib->nr_frags; 
curfragnum++) {
-                               iv = pframe+pattrib->hdrlen;
-                               payload = 
pframe+pattrib->iv_len+pattrib->hdrlen;
+       if (is_multicast_ether_addr(pattrib->ra))
+               prwskey = 
psecuritypriv->dot118021XGrpKey[psecuritypriv->dot118021XGrpKeyid].skey;
+       else
+               prwskey = &stainfo->dot118021x_UncstKey.skey[0];
 
-                               GET_TKIP_PN(iv, dot11txpn);
+       prwskeylen = 16;
 
-                               pnl = (u16)(dot11txpn.val);
-                               pnh = (u32)(dot11txpn.val>>16);
+       for (curfragnum = 0; curfragnum < pattrib->nr_frags; curfragnum++) {
+               iv = pframe+pattrib->hdrlen;
+               payload = pframe+pattrib->iv_len+pattrib->hdrlen;
 
-                               phase1((u16 *)&ttkey[0], prwskey, 
&pattrib->ta[0], pnh);
+               GET_TKIP_PN(iv, dot11txpn);
 
-                               phase2(&rc4key[0], prwskey, (u16 *)&ttkey[0], 
pnl);
+               pnl = (u16)(dot11txpn.val);
+               pnh = (u32)(dot11txpn.val>>16);
 
-                               if ((curfragnum + 1) == pattrib->nr_frags) {    
/* 4 the last fragment */
-                                       length = 
pattrib->last_txcmdsz-pattrib->hdrlen-pattrib->iv_len - pattrib->icv_len;
-                                       RT_TRACE(_module_rtl871x_security_c_, 
_drv_info_, ("pattrib->iv_len =%x, pattrib->icv_len =%x\n", pattrib->iv_len, 
pattrib->icv_len));
-                                       *((u32 *)crc) = 
cpu_to_le32(getcrc32(payload, length));/* modified by Amy*/
+               phase1((u16 *)&ttkey[0], prwskey, &pattrib->ta[0], pnh);
 
-                                       arcfour_init(&mycontext, rc4key, 16);
-                                       arcfour_encrypt(&mycontext, payload, 
payload, length);
-                                       arcfour_encrypt(&mycontext, 
payload+length, crc, 4);
+               phase2(&rc4key[0], prwskey, (u16 *)&ttkey[0], pnl);
 
-                               } else {
-                                       length = 
pxmitpriv->frag_len-pattrib->hdrlen-pattrib->iv_len-pattrib->icv_len;
-                                       *((u32 *)crc) = 
cpu_to_le32(getcrc32(payload, length));/* modified by Amy*/
-                                       arcfour_init(&mycontext, rc4key, 16);
-                                       arcfour_encrypt(&mycontext, payload, 
payload, length);
-                                       arcfour_encrypt(&mycontext, 
payload+length, crc, 4);
+               if ((curfragnum+1) == pattrib->nr_frags) {      /* 4 the last 
fragment */
+                       length = 
pattrib->last_txcmdsz-pattrib->hdrlen-pattrib->iv_len - pattrib->icv_len;
+                       RT_TRACE(_module_rtl871x_security_c_, _drv_info_, 
("pattrib->iv_len =%x, pattrib->icv_len =%x\n", pattrib->iv_len, 
pattrib->icv_len));
+                       *((u32 *)crc) = cpu_to_le32(getcrc32(payload, 
length));/* modified by Amy*/
 
-                                       pframe += pxmitpriv->frag_len;
-                                       pframe  = PTR_ALIGN(pframe, 4);
-                               }
-                       }
+                       arcfour_init(&mycontext, rc4key, 16);
+                       arcfour_encrypt(&mycontext, payload, payload, length);
+                       arcfour_encrypt(&mycontext, payload+length, crc, 4);
 
                } else {
-                       RT_TRACE(_module_rtl871x_security_c_, _drv_err_, 
("rtw_tkip_encrypt23a: stainfo == NULL!!!\n"));
-                       DBG_8723A("%s, psta == NUL\n", __func__);
-                       res = _FAIL;
-               }
+                       length = 
pxmitpriv->frag_len-pattrib->hdrlen-pattrib->iv_len-pattrib->icv_len;
+                       *((u32 *)crc) = cpu_to_le32(getcrc32(payload, 
length));/* modified by Amy*/
+                       arcfour_init(&mycontext, rc4key, 16);
+                       arcfour_encrypt(&mycontext, payload, payload, length);
+                       arcfour_encrypt(&mycontext, payload+length, crc, 4);
 
+                       pframe += pxmitpriv->frag_len;
+                       pframe  = PTR_ALIGN(pframe, 4);
+               }
        }
 
        return res;
@@ -715,58 +713,58 @@ int rtw_tkip_decrypt23a(struct rtw_adapter *padapter,
        struct sk_buff *skb = precvframe->pkt;
        int res = _SUCCESS;
 
+       if (prxattrib->encrypt != WLAN_CIPHER_SUITE_TKIP)
+               return _FAIL;
+
        pframe = skb->data;
 
        /* 4 start to decrypt recvframe */
-       if (prxattrib->encrypt == WLAN_CIPHER_SUITE_TKIP) {
+       stainfo = rtw_get_stainfo23a(&padapter->stapriv,
+                                    &prxattrib->ta[0]);
+       if (stainfo == NULL) {
+               RT_TRACE(_module_rtl871x_security_c_, _drv_err_, 
("rtw_tkip_decrypt23a: stainfo == NULL!!!\n"));
+               return _FAIL;
+       }
 
-               stainfo = rtw_get_stainfo23a(&padapter->stapriv,
-                                            &prxattrib->ta[0]);
-               if (stainfo!= NULL) {
-
-                       if (is_multicast_ether_addr(prxattrib->ra)) {
-                               if (psecuritypriv->binstallGrpkey == 0) {
-                                       res = _FAIL;
-                                       DBG_8723A("%s:rx bc/mc packets, but 
didn't install group key!!!!!!!!!!\n", __func__);
-                                       goto exit;
-                               }
-                               prwskey = 
psecuritypriv->dot118021XGrpKey[prxattrib->key_index].skey;
-                               prwskeylen = 16;
-                       } else {
-                               RT_TRACE(_module_rtl871x_security_c_, 
_drv_err_, ("rtw_tkip_decrypt23a: stainfo!= NULL!!!\n"));
-                               prwskey = &stainfo->dot118021x_UncstKey.skey[0];
-                               prwskeylen = 16;
-                       }
+       if (is_multicast_ether_addr(prxattrib->ra)) {
+               if (psecuritypriv->binstallGrpkey == 0) {
+                       res = _FAIL;
+                       DBG_8723A("%s:rx bc/mc packets, but didn't install 
group key!!!!!!!!!!\n", __func__);
+                       goto exit;
+               }
+               prwskey = 
psecuritypriv->dot118021XGrpKey[prxattrib->key_index].skey;
+               prwskeylen = 16;
+       } else {
+               RT_TRACE(_module_rtl871x_security_c_, _drv_err_, 
("rtw_tkip_decrypt23a: stainfo!= NULL!!!\n"));
+               prwskey = &stainfo->dot118021x_UncstKey.skey[0];
+               prwskeylen = 16;
+       }
 
-                       iv = pframe+prxattrib->hdrlen;
-                       payload = pframe+prxattrib->iv_len+prxattrib->hdrlen;
-                       length = skb->len - prxattrib->hdrlen-prxattrib->iv_len;
+       iv = pframe+prxattrib->hdrlen;
+       payload = pframe+prxattrib->iv_len+prxattrib->hdrlen;
+       length = skb->len - prxattrib->hdrlen-prxattrib->iv_len;
 
-                       GET_TKIP_PN(iv, dot11txpn);
+       GET_TKIP_PN(iv, dot11txpn);
 
-                       pnl = (u16)(dot11txpn.val);
-                       pnh = (u32)(dot11txpn.val>>16);
+       pnl = (u16)(dot11txpn.val);
+       pnh = (u32)(dot11txpn.val>>16);
 
-                       phase1((u16 *)&ttkey[0], prwskey, &prxattrib->ta[0], 
pnh);
-                       phase2(&rc4key[0], prwskey, (unsigned short 
*)&ttkey[0], pnl);
+       phase1((u16 *)&ttkey[0], prwskey, &prxattrib->ta[0], pnh);
+       phase2(&rc4key[0], prwskey, (unsigned short *)&ttkey[0], pnl);
 
-                       /* 4 decrypt payload include icv */
-                       arcfour_init(&mycontext, rc4key, 16);
-                       arcfour_encrypt(&mycontext, payload, payload, length);
+       /* 4 decrypt payload include icv */
+       arcfour_init(&mycontext, rc4key, 16);
+       arcfour_encrypt(&mycontext, payload, payload, length);
 
-                       *((u32 *)crc) = le32_to_cpu(getcrc32(payload, length - 
4));
+       *((u32 *)crc) = le32_to_cpu(getcrc32(payload, length - 4));
 
-                       if (crc[3] != payload[length - 1] || crc[2] != 
payload[length - 2] || crc[1] != payload[length - 3] || crc[0] != 
payload[length - 4])
-                       {
-                           RT_TRACE(_module_rtl871x_security_c_, _drv_err_, 
("rtw_wep_decrypt23a:icv error crc[3](%x)!= payload[length-1](%x) || 
crc[2](%x)!= payload[length-2](%x) || crc[1](%x)!= payload[length-3](%x) || 
crc[0](%x)!= payload[length-4](%x)\n",
-                                               crc[3], payload[length - 1], 
crc[2], payload[length - 2], crc[1], payload[length - 3], crc[0], 
payload[length - 4]));
-                               res = _FAIL;
-                       }
-               } else {
-                       RT_TRACE(_module_rtl871x_security_c_, _drv_err_, 
("rtw_tkip_decrypt23a: stainfo == NULL!!!\n"));
-                       res = _FAIL;
-               }
+       if (crc[3] != payload[length - 1] || crc[2] != payload[length - 2] || 
crc[1] != payload[length - 3] || crc[0] != payload[length - 4])
+       {
+           RT_TRACE(_module_rtl871x_security_c_, _drv_err_, 
("rtw_wep_decrypt23a:icv error crc[3](%x)!= payload[length-1](%x) || 
crc[2](%x)!= payload[length-2](%x) || crc[1](%x)!= payload[length-3](%x) || 
crc[0](%x)!= payload[length-4](%x)\n",
+                               crc[3], payload[length - 1], crc[2], 
payload[length - 2], crc[1], payload[length - 3], crc[0], payload[length - 4]));
+               res = _FAIL;
        }
+
 exit:
        return res;
 }
-- 
2.1.4

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