staging: rtl8723bs: reduce nesting in rtw_security.c

Improve readability of functions:
rtw_tkip_encrypt, rtw_tkip_decrypt, rtw_aes_encrypt
in rtw_security.c by adding early returns for the
encryption type check and the stainfo null check.

Signed-off-by: Maksym Pikhotskyi <mpikhotskyi@gmail.com>
Reviewed-by: Luka Gejak <luka.gejak@linux.dev>
Link: https://patch.msgid.link/20260417095452.23440-2-mpikhotskyi@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/rtl8723bs/core/rtw_security.c b/drivers/staging/rtl8723bs/core/rtw_security.c
index f467cb5b1dca39010b6d8d6806949a6af85c0984..2a5a4c0de9b14e87593e1209541042761a1a393c 100644 (file)
--- a/drivers/staging/rtl8723bs/core/rtw_security.c
+++ b/drivers/staging/rtl8723bs/core/rtw_security.c
@@ -449,47 +449,45 @@ u32 rtw_tkip_encrypt(struct adapter *padapter, u8 *pxmitframe)
        pframe = ((struct xmit_frame *)pxmitframe)->buf_addr + hw_hdr_offset;
 
        /* 4 start to encrypt each fragment */
-       if (pattrib->encrypt == _TKIP_) {
+       if (pattrib->encrypt != _TKIP_)
+               return _SUCCESS;
 
-               {
-                       if (is_multicast_ether_addr(pattrib->ra))
-                               prwskey = psecuritypriv->dot118021XGrpKey[psecuritypriv->dot118021XGrpKeyid].skey;
-                       else
-                               prwskey = pattrib->dot118021x_UncstKey.skey;
+       if (is_multicast_ether_addr(pattrib->ra))
+               prwskey = psecuritypriv->dot118021XGrpKey[psecuritypriv->dot118021XGrpKeyid].skey;
+       else
+               prwskey = pattrib->dot118021x_UncstKey.skey;
 
-                       for (curfragnum = 0; curfragnum < pattrib->nr_frags; curfragnum++) {
-                               iv = pframe + pattrib->hdrlen;
-                               payload = pframe + pattrib->iv_len + pattrib->hdrlen;
+       for (curfragnum = 0; curfragnum < pattrib->nr_frags; curfragnum++) {
+               iv = pframe + pattrib->hdrlen;
+               payload = pframe + pattrib->iv_len + pattrib->hdrlen;
 
-                               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, &pattrib->ta[0], pnh);
+               phase1((u16 *)&ttkey[0], prwskey, &pattrib->ta[0], pnh);
 
-                               phase2(&rc4key[0], prwskey, (u16 *)&ttkey[0], pnl);
+               phase2(&rc4key[0], prwskey, (u16 *)&ttkey[0], pnl);
 
-                               if ((curfragnum + 1) == pattrib->nr_frags) {    /* 4 the last fragment */
-                                       length = pattrib->last_txcmdsz - pattrib->hdrlen - pattrib->iv_len - pattrib->icv_len;
-                                       crc.f0 = cpu_to_le32(~crc32_le(~0, payload, length));
+               if ((curfragnum + 1) == pattrib->nr_frags) {    /* 4 the last fragment */
+                       length = pattrib->last_txcmdsz - pattrib->hdrlen - pattrib->iv_len - pattrib->icv_len;
+                       crc.f0 = cpu_to_le32(~crc32_le(~0, payload, length));
 
-                                       arc4_setkey(ctx, rc4key, 16);
-                                       arc4_crypt(ctx, payload, payload, length);
-                                       arc4_crypt(ctx, payload + length, crc.f1, 4);
+                       arc4_setkey(ctx, rc4key, 16);
+                       arc4_crypt(ctx, payload, payload, length);
+                       arc4_crypt(ctx, payload + length, crc.f1, 4);
 
-                               } else {
-                                       length = pxmitpriv->frag_len - pattrib->hdrlen - pattrib->iv_len - pattrib->icv_len;
-                                       crc.f0 = cpu_to_le32(~crc32_le(~0, payload, length));
+               } else {
+                       length = pxmitpriv->frag_len - pattrib->hdrlen - pattrib->iv_len - pattrib->icv_len;
+                       crc.f0 = cpu_to_le32(~crc32_le(~0, payload, length));
 
-                                       arc4_setkey(ctx, rc4key, 16);
-                                       arc4_crypt(ctx, payload, payload, length);
-                                       arc4_crypt(ctx, payload + length, crc.f1, 4);
+                       arc4_setkey(ctx, rc4key, 16);
+                       arc4_crypt(ctx, payload, payload, length);
+                       arc4_crypt(ctx, payload + length, crc.f1, 4);
 
-                                       pframe += pxmitpriv->frag_len;
-                                       pframe = (u8 *)round_up((SIZE_PTR)(pframe), 4);
-                               }
-                       }
+                       pframe += pxmitpriv->frag_len;
+                       pframe = (u8 *)round_up((SIZE_PTR)(pframe), 4);
                }
        }
        return res;
@@ -517,82 +515,82 @@ u32 rtw_tkip_decrypt(struct adapter *padapter, u8 *precvframe)
        pframe = (unsigned char *)((union recv_frame *)precvframe)->u.hdr.rx_data;
 
        /* 4 start to decrypt recvframe */
-       if (prxattrib->encrypt == _TKIP_) {
-               stainfo = rtw_get_stainfo(&padapter->stapriv, &prxattrib->ta[0]);
-               if (stainfo) {
-                       if (is_multicast_ether_addr(prxattrib->ra)) {
-                               static unsigned long start;
-                               static u32 no_gkey_bc_cnt;
-                               static u32 no_gkey_mc_cnt;
-
-                               if (!psecuritypriv->binstallGrpkey) {
-                                       res = _FAIL;
-
-                                       if (start == 0)
-                                               start = jiffies;
-
-                                       if (is_broadcast_ether_addr(prxattrib->ra))
-                                               no_gkey_bc_cnt++;
-                                       else
-                                               no_gkey_mc_cnt++;
-
-                                       if (jiffies_to_msecs(jiffies - start) > 1000) {
-                                               if (no_gkey_bc_cnt || no_gkey_mc_cnt) {
-                                                       netdev_dbg(padapter->pnetdev,
-                                                                  FUNC_ADPT_FMT " no_gkey_bc_cnt:%u, no_gkey_mc_cnt:%u\n",
-                                                                  FUNC_ADPT_ARG(padapter),
-                                                                  no_gkey_bc_cnt,
-                                                                  no_gkey_mc_cnt);
-                                               }
-                                               start = jiffies;
-                                               no_gkey_bc_cnt = 0;
-                                               no_gkey_mc_cnt = 0;
-                                       }
-                                       goto exit;
-                               }
+       if (prxattrib->encrypt != _TKIP_)
+               return _SUCCESS;
 
+       stainfo = rtw_get_stainfo(&padapter->stapriv, &prxattrib->ta[0]);
+       if (!stainfo)
+               return _FAIL;
+
+       if (is_multicast_ether_addr(prxattrib->ra)) {
+               static unsigned long start;
+               static u32 no_gkey_bc_cnt;
+               static u32 no_gkey_mc_cnt;
+
+               if (!psecuritypriv->binstallGrpkey) {
+                       res = _FAIL;
+
+                       if (start == 0)
+                               start = jiffies;
+
+                       if (is_broadcast_ether_addr(prxattrib->ra))
+                               no_gkey_bc_cnt++;
+                       else
+                               no_gkey_mc_cnt++;
+
+                       if (jiffies_to_msecs(jiffies - start) > 1000) {
                                if (no_gkey_bc_cnt || no_gkey_mc_cnt) {
                                        netdev_dbg(padapter->pnetdev,
-                                                  FUNC_ADPT_FMT " gkey installed. no_gkey_bc_cnt:%u, no_gkey_mc_cnt:%u\n",
+                                                  FUNC_ADPT_FMT " no_gkey_bc_cnt:%u, no_gkey_mc_cnt:%u\n",
                                                   FUNC_ADPT_ARG(padapter),
                                                   no_gkey_bc_cnt,
                                                   no_gkey_mc_cnt);
                                }
-                               start = 0;
+                               start = jiffies;
                                no_gkey_bc_cnt = 0;
                                no_gkey_mc_cnt = 0;
-
-                               prwskey = psecuritypriv->dot118021XGrpKey[prxattrib->key_index].skey;
-                       } else {
-                               prwskey = &stainfo->dot118021x_UncstKey.skey[0];
                        }
+                       goto exit;
+               }
 
-                       iv = pframe + prxattrib->hdrlen;
-                       payload = pframe + prxattrib->iv_len + prxattrib->hdrlen;
-                       length = ((union recv_frame *)precvframe)->u.hdr.len - prxattrib->hdrlen - prxattrib->iv_len;
+               if (no_gkey_bc_cnt || no_gkey_mc_cnt) {
+                       netdev_dbg(padapter->pnetdev,
+                                  FUNC_ADPT_FMT " gkey installed. no_gkey_bc_cnt:%u, no_gkey_mc_cnt:%u\n",
+                                  FUNC_ADPT_ARG(padapter),
+                                  no_gkey_bc_cnt,
+                                  no_gkey_mc_cnt);
+               }
+               start = 0;
+               no_gkey_bc_cnt = 0;
+               no_gkey_mc_cnt = 0;
 
-                       GET_TKIP_PN(iv, dot11txpn);
+               prwskey = psecuritypriv->dot118021XGrpKey[prxattrib->key_index].skey;
+       } else {
+               prwskey = &stainfo->dot118021x_UncstKey.skey[0];
+       }
 
-                       pnl = (u16)(dot11txpn.val);
-                       pnh = (u32)(dot11txpn.val >> 16);
+       iv = pframe + prxattrib->hdrlen;
+       payload = pframe + prxattrib->iv_len + prxattrib->hdrlen;
+       length = ((union recv_frame *)precvframe)->u.hdr.len - prxattrib->hdrlen - prxattrib->iv_len;
 
-                       phase1((u16 *)&ttkey[0], prwskey, &prxattrib->ta[0], pnh);
-                       phase2(&rc4key[0], prwskey, (unsigned short *)&ttkey[0], pnl);
+       GET_TKIP_PN(iv, dot11txpn);
 
-                       /* 4 decrypt payload include icv */
+       pnl = (u16)(dot11txpn.val);
+       pnh = (u32)(dot11txpn.val >> 16);
 
-                       arc4_setkey(ctx, rc4key, 16);
-                       arc4_crypt(ctx, payload, payload, length);
+       phase1((u16 *)&ttkey[0], prwskey, &prxattrib->ta[0], pnh);
+       phase2(&rc4key[0], prwskey, (unsigned short *)&ttkey[0], pnl);
 
-                       *((u32 *)crc) = ~crc32_le(~0, payload, length - 4);
+       /* 4 decrypt payload include icv */
 
-                       if (crc[3] != payload[length - 1] || crc[2] != payload[length - 2] ||
-                           crc[1] != payload[length - 3] || crc[0] != payload[length - 4])
-                               res = _FAIL;
-               } else {
-                       res = _FAIL;
-               }
-       }
+       arc4_setkey(ctx, rc4key, 16);
+       arc4_crypt(ctx, payload, payload, length);
+
+       *((u32 *)crc) = ~crc32_le(~0, payload, length - 4);
+
+       if (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;
 }
@@ -965,24 +963,25 @@ u32 rtw_aes_encrypt(struct adapter *padapter, u8 *pxmitframe)
        pframe = ((struct xmit_frame *)pxmitframe)->buf_addr + hw_hdr_offset;
 
        /* 4 start to encrypt each fragment */
-       if (pattrib->encrypt == _AES_) {
-               if (is_multicast_ether_addr(pattrib->ra))
-                       prwskey = psecuritypriv->dot118021XGrpKey[psecuritypriv->dot118021XGrpKeyid].skey;
-               else
-                       prwskey = pattrib->dot118021x_UncstKey.skey;
+       if (pattrib->encrypt != _AES_)
+               return _SUCCESS;
 
-               for (curfragnum = 0; curfragnum < pattrib->nr_frags; curfragnum++) {
-                       if ((curfragnum + 1) == pattrib->nr_frags) {    /* 4 the last fragment */
-                               length = pattrib->last_txcmdsz - pattrib->hdrlen - pattrib->iv_len - pattrib->icv_len;
+       if (is_multicast_ether_addr(pattrib->ra))
+               prwskey = psecuritypriv->dot118021XGrpKey[psecuritypriv->dot118021XGrpKeyid].skey;
+       else
+               prwskey = pattrib->dot118021x_UncstKey.skey;
 
-                               aes_cipher(prwskey, pattrib->hdrlen, pframe, length);
-                       } else {
-                               length = pxmitpriv->frag_len - pattrib->hdrlen - pattrib->iv_len - pattrib->icv_len;
+       for (curfragnum = 0; curfragnum < pattrib->nr_frags; curfragnum++) {
+               if ((curfragnum + 1) == pattrib->nr_frags) {    /* 4 the last fragment */
+                       length = pattrib->last_txcmdsz - pattrib->hdrlen - pattrib->iv_len - pattrib->icv_len;
 
-                               aes_cipher(prwskey, pattrib->hdrlen, pframe, length);
-                               pframe += pxmitpriv->frag_len;
-                               pframe = (u8 *)round_up((SIZE_PTR)(pframe), 4);
-                       }
+                       aes_cipher(prwskey, pattrib->hdrlen, pframe, length);
+               } else {
+                       length = pxmitpriv->frag_len - pattrib->hdrlen - pattrib->iv_len - pattrib->icv_len;
+
+                       aes_cipher(prwskey, pattrib->hdrlen, pframe, length);
+                       pframe += pxmitpriv->frag_len;
+                       pframe = (u8 *)round_up((SIZE_PTR)(pframe), 4);
                }
        }
        return res;