staging: rtl8723au: Reorganize a few functions to remove indentation

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.v.b@runbox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/rtl8723au/core/rtw_security.c b/drivers/staging/rtl8723au/core/rtw_security.c
index 3e79b66..df7261c 100644 (file)
--- a/drivers/staging/rtl8723au/core/rtw_security.c
+++ b/drivers/staging/rtl8723au/core/rtw_security.c
@@ -615,91 +615,90 @@ 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;
 
        hw_hdr_offset = TXDESC_OFFSET;
 
        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 (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->state & _FW_LINKED)) {
-                               DBG_8723A("%s, psta->state(0x%x) != _FW_LINKED\n", __func__, stainfo->state);
-                               return _FAIL;
-                       }
+       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;
+       }
 
-                       RT_TRACE(_module_rtl871x_security_c_, _drv_err_,
-                                "rtw_tkip_encrypt23a: stainfo!= NULL!!!\n");
+       RT_TRACE(_module_rtl871x_security_c_, _drv_err_,
+                "rtw_tkip_encrypt23a: stainfo!= NULL!!!\n");
 
-                       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;
+       if (is_multicast_ether_addr(pattrib->ra))
+               prwskey = psecuritypriv->dot118021XGrpKey[psecuritypriv->dot118021XGrpKeyid].skey;
+       else
+               prwskey = &stainfo->dot118021x_UncstKey.skey[0];
 
-                       for (curfragnum = 0; curfragnum < pattrib->nr_frags; curfragnum++) {
-                               iv = pframe + pattrib->hdrlen;
-                               payload = pframe + pattrib->iv_len + pattrib->hdrlen;
+       prwskeylen = 16;
 
-                               GET_TKIP_PN(iv, dot11txpn);
+       /* 4 start to encrypt each fragment */
+       for (curfragnum = 0; curfragnum < pattrib->nr_frags; curfragnum++) {
+               iv = pframe + pattrib->hdrlen;
+               payload = pframe + pattrib->iv_len + pattrib->hdrlen;
 
-                               pnl = (u16)(dot11txpn.val);
-                               pnh = (u32)(dot11txpn.val>>16);
+               GET_TKIP_PN(iv, dot11txpn);
 
-                               phase1((u16 *)&ttkey[0], prwskey, &pattrib->ta[0], pnh);
+               pnl = (u16)(dot11txpn.val);
+               pnh = (u32)(dot11txpn.val>>16);
 
-                               phase2(&rc4key[0], prwskey, (u16 *)&ttkey[0], pnl);
+               phase1((u16 *)&ttkey[0], prwskey, &pattrib->ta[0], pnh);
 
-                               if ((curfragnum + 1) == pattrib->nr_frags) {    /* 4 the last fragment */
-                                       length = (pattrib->last_txcmdsz -
-                                                 pattrib->hdrlen -
-                                                 pattrib->iv_len -
-                                                 pattrib->icv_len);
+               phase2(&rc4key[0], prwskey, (u16 *)&ttkey[0], pnl);
 
-                                       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*/
+               if ((curfragnum + 1) == pattrib->nr_frags) {    /* 4 the last fragment */
+                       length = (pattrib->last_txcmdsz -
+                                 pattrib->hdrlen -
+                                 pattrib->iv_len -
+                                 pattrib->icv_len);
 
-                                       arcfour_init(&mycontext, rc4key, 16);
-                                       arcfour_encrypt(&mycontext, payload, payload, length);
-                                       arcfour_encrypt(&mycontext, payload + length, crc, 4);
+                       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*/
 
-                               } else {
-                                       length = (pxmitpriv->frag_len -
-                                                 pattrib->hdrlen -
-                                                 pattrib->iv_len -
-                                                 pattrib->icv_len);
+                       arcfour_init(&mycontext, rc4key, 16);
+                       arcfour_encrypt(&mycontext, payload, payload, length);
+                       arcfour_encrypt(&mycontext, payload + length, crc, 4);
 
-                                       *((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);
+               } else {
+                       length = (pxmitpriv->frag_len -
+                                 pattrib->hdrlen -
+                                 pattrib->iv_len -
+                                 pattrib->icv_len);
 
-                                       pframe += pxmitpriv->frag_len;
-                                       pframe  = PTR_ALIGN(pframe, 4);
-                               }
-                       }
+                       *((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);
 
-               } else {
-                       RT_TRACE(_module_rtl871x_security_c_, _drv_err_,
-                                "rtw_tkip_encrypt23a: stainfo == NULL!!!\n");
-                       DBG_8723A("%s, psta == NUL\n", __func__);
-                       res = _FAIL;
+                       pframe += pxmitpriv->frag_len;
+                       pframe  = PTR_ALIGN(pframe, 4);
                }
-
        }
 
        return res;
@@ -725,64 +724,64 @@ 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;
 
+       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;
+       }
+
        /* 4 start to decrypt recvframe */
-       if (prxattrib->encrypt == WLAN_CIPHER_SUITE_TKIP) {
+       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;
+       }
 
-               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;
-                       }
+       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;
 }