Return-path: Received: from mail-qk0-f179.google.com ([209.85.220.179]:36545 "EHLO mail-qk0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933609AbbELWYm convert rfc822-to-8bit (ORCPT ); Tue, 12 May 2015 18:24:42 -0400 Received: by qku63 with SMTP id 63so16508489qku.3 for ; Tue, 12 May 2015 15:24:41 -0700 (PDT) Message-ID: <55527D6E.7090207@gmail.com> (sfid-20150513_002446_503497_EE5FFF34) Date: Tue, 12 May 2015 19:23:42 -0300 From: Gaston Gonzalez MIME-Version: 1.0 To: Dan Carpenter CC: devel@driverdev.osuosl.org, arnd@arndb.de, gregkh@linuxfoundation.org, linux-wireless@vger.kernel.org, joe@perches.com, navyasri.tech@gmail.com Subject: Re: [PATCH] staging: rtl8192u: ieee80211: Silence sparse warning References: <1429476231-6197-1-git-send-email-gascoar@gmail.com> <20150420082441.GU10964@mwanda> <553C18B6.807@gmail.com> <20150427101242.GR14154@mwanda> <554AD76E.7060605@gmail.com> <20150508110328.GT14154@mwanda> In-Reply-To: <20150508110328.GT14154@mwanda> Content-Type: text/plain; charset=windows-1252 Sender: linux-wireless-owner@vger.kernel.org List-ID: On 08/05/15 08:03, Dan Carpenter wrote: > To be honest, I'm a little bit a newbie myself when it comes to > linux-wireless so keep that in mind. ;) Changing the parameters seems > simple enough. But it needs to an EXPORT_SYMBOL() and to be declared in > a header file and I'm not sure what else. But we have four > implementations of this function now. Ok Dan, I did the test exporting tkip_mixing_phase2(). Below is how the patch would look. So far I didn't get any warnings. Summary and comments: - Goal: use tkip_mixing_phase2() from /net/mac80211/tkip.c in drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_tkip.c - Approach: export tkip_mixing_phase2(), adding tkip_ctx structure definition without toucing original structures from ieee80211_crypt_tkip.c. As you pointed out, this is done by adding EXPORT_SYMBOL() and declaring the function in the destined file. - As commented in the previous email, adding tkip_ctx structure duplicates some members. Only one of them is used in the function: p1k, so it is copied from one structure to the other. - Please let me know if the implementation is useful or is better another approach or if it needs changes. - In the case this is well oriented, the submission form would be a new patch or v2 of the original one? regards, Gaston --- .../rtl8192u/ieee80211/ieee80211_crypt_tkip.c | 79 ++++++++-------------- net/mac80211/tkip.c | 3 +- 2 files changed, 32 insertions(+), 50 deletions(-) diff --git a/drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_tkip.c b/drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_tkip.c index 1f80c52..51e2034 100644 --- a/drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_tkip.c +++ b/drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_tkip.c @@ -18,3 +18,4 @@ #include #include #include +#include #include "ieee80211.h" @@ -61,2 +62,2 @@ struct ieee80211_tkip_data { u8 rx_hdr[16], tx_hdr[16]; }; +enum ieee80211_internal_tkip_state { + TKIP_STATE_NOT_INIT, + TKIP_STATE_PHASE1_DONE, + TKIP_STATE_PHASE1_HW_UPLOADED, +}; + +struct tkip_ctx { + u32 iv32; /* current iv32 */ + u16 iv16; /* current iv16 */ + u16 p1k[5]; /* p1k cache */ + u32 p1k_iv32; /* iv32 for which p1k computed */ + enum ieee80211_internal_tkip_state state; +}; + +void tkip_mixing_phase2(const u8 *tk, struct tkip_ctx *ctx, + u16 tsc_IV16, u8 *rc4key); + static void *ieee80211_tkip_init(int key_idx) { struct ieee80211_tkip_data *priv; @@ -254,1 +272,1 @@ static void tkip_mixing_phase1(u16 *TTAK, const u8 *TK, const u8 *TA, u32 IV32) } -static void tkip_mixing_phase2(u8 *WEPSeed, const u8 *TK, const u16 *TTAK, - u16 IV16) -{ - /* Make temporary area overlap WEP seed so that the final copy can be - * avoided on little endian hosts. */ - u16 *PPK = (u16 *) &WEPSeed[4]; - - /* Step 1 - make copy of TTAK and bring in TSC */ - PPK[0] = TTAK[0]; - PPK[1] = TTAK[1]; - PPK[2] = TTAK[2]; - PPK[3] = TTAK[3]; - PPK[4] = TTAK[4]; - PPK[5] = TTAK[4] + IV16; - - /* Step 2 - 96-bit bijective mixing using S-box */ - PPK[0] += _S_(PPK[5] ^ Mk16_le((u16 *) &TK[0])); - PPK[1] += _S_(PPK[0] ^ Mk16_le((u16 *) &TK[2])); - PPK[2] += _S_(PPK[1] ^ Mk16_le((u16 *) &TK[4])); - PPK[3] += _S_(PPK[2] ^ Mk16_le((u16 *) &TK[6])); - PPK[4] += _S_(PPK[3] ^ Mk16_le((u16 *) &TK[8])); - PPK[5] += _S_(PPK[4] ^ Mk16_le((u16 *) &TK[10])); - - PPK[0] += RotR1(PPK[5] ^ Mk16_le((u16 *) &TK[12])); - PPK[1] += RotR1(PPK[0] ^ Mk16_le((u16 *) &TK[14])); - PPK[2] += RotR1(PPK[1]); - PPK[3] += RotR1(PPK[2]); - PPK[4] += RotR1(PPK[3]); - PPK[5] += RotR1(PPK[4]); - - /* Step 3 - bring in last of TK bits, assign 24-bit WEP IV value - * WEPSeed[0..2] is transmitted as WEP IV */ - WEPSeed[0] = Hi8(IV16); - WEPSeed[1] = (Hi8(IV16) | 0x20) & 0x7F; - WEPSeed[2] = Lo8(IV16); - WEPSeed[3] = Lo8((PPK[5] ^ Mk16_le((u16 *) &TK[0])) >> 1); - -#ifdef __BIG_ENDIAN - { - int i; - for (i = 0; i < 6; i++) - PPK[i] = (PPK[i] << 8) | (PPK[i] >> 8); - } -#endif -} - - static int ieee80211_tkip_encrypt(struct sk_buff *skb, int hdr_len, void *priv) { struct ieee80211_tkip_data *tkey = priv; int len; u8 *pos; + struct tkip_ctx *tx = NULL; + size_t p1k_len; struct rtl_80211_hdr_4addr *hdr; cb_desc *tcb_desc = (cb_desc *)(skb->cb + MAX_DEV_ADDR_SIZE); struct blkcipher_desc desc = {.tfm = tkey->tx_tfm_arc4}; @@ -314,2 +287,2 @@ static int ieee80211_tkip_encrypt(struct sk_buff *skb, int hdr_len, void *priv) u32 crc; struct scatterlist sg; + p1k_len = sizeof(tkey->tx_ttak); + memcpy(&tx->p1k, &tkey->tx_ttak, p1k_len); + if (skb_headroom(skb) < 8 || skb_tailroom(skb) < 4 || skb->len < hdr_len) return -1; @@ -327,7 +303,7 @@ static int ieee80211_tkip_encrypt(struct sk_buff *skb, int hdr_len, void *priv) tkey->tx_iv32); tkey->tx_phase1_done = 1; } - tkip_mixing_phase2(rc4key, tkey->key, tkey->tx_ttak, tkey->tx_iv16); + tkip_mixing_phase2(tkey->key, tx, tkey->tx_iv16, rc4key); } else tkey->tx_phase1_done = 1; @@ -387,6 +363,8 @@ static int ieee80211_tkip_encrypt(struct sk_buff *skb, int hdr_len, void *priv) static int ieee80211_tkip_decrypt(struct sk_buff *skb, int hdr_len, void *priv) { struct ieee80211_tkip_data *tkey = priv; + struct tkip_ctx *rx = NULL; + size_t p1k_len; u8 keyidx, *pos; u32 iv32; u16 iv16; @@ -401,2 +379,2 @@ static int ieee80211_tkip_decrypt(struct sk_buff *skb, int hdr_len, void *priv) if (skb->len < hdr_len + 8 + 4) return -1; + p1k_len = sizeof(tkey->rx_ttak); + memcpy(&rx->p1k, &tkey->rx_ttak, p1k_len); + hdr = (struct rtl_80211_hdr_4addr *) skb->data; pos = skb->data + hdr_len; keyidx = pos[3]; @@ -447,4 +428,4 @@ static int ieee80211_tkip_decrypt(struct sk_buff *skb, int hdr_len, void *priv) tkip_mixing_phase1(tkey->rx_ttak, tkey->key, hdr->addr2, iv32); tkey->rx_phase1_done = 1; } - tkip_mixing_phase2(rc4key, tkey->key, tkey->rx_ttak, iv16); + tkip_mixing_phase2(tkey->key, rx, tkey->rx_iv16, rc4key); plen = skb->len - hdr_len - 12; diff --git a/net/mac80211/tkip.c b/net/mac80211/tkip.c index 0ae2077..1f74866 100644 --- a/net/mac80211/tkip.c +++ b/net/mac80211/tkip.c @@ -105,2 +105,2 @@ static void tkip_mixing_phase1(const u8 *tk, struct tkip_ctx *ctx, ctx->p1k_iv32 = tsc_IV32; } -static void tkip_mixing_phase2(const u8 *tk, struct tkip_ctx *ctx, +void tkip_mixing_phase2(const u8 *tk, struct tkip_ctx *ctx, u16 tsc_IV16, u8 *rc4key) { u16 ppk[6]; @@ -138,3 +138,4 @@ static void tkip_mixing_phase2(const u8 *tk, struct tkip_ctx *ctx, for (i = 0; i < 6; i++) put_unaligned_le16(ppk[i], rc4key + 2 * i); } +EXPORT_SYMBOL(tkip_mixing_phase2); /* Add TKIP IV and Ext. IV at @pos. @iv0, @iv1, and @iv2 are the first octets * of the IV. Returns pointer to the octet following IVs (i.e., beginning of -- 2.1.4