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* [RFC PATCH 0/7] crypto: get rid of ecb(arc4)
@ 2020-07-02 10:19 Ard Biesheuvel
  2020-07-02 10:19 ` [RFC PATCH 1/7] staging/rtl8192e: switch to RC4 library interface Ard Biesheuvel
                   ` (6 more replies)
  0 siblings, 7 replies; 17+ messages in thread
From: Ard Biesheuvel @ 2020-07-02 10:19 UTC (permalink / raw)
  To: linux-kernel
  Cc: Ard Biesheuvel, Herbert Xu, David S. Miller, Greg Kroah-Hartman,
	Trond Myklebust, Anna Schumaker, J. Bruce Fields, Chuck Lever,
	Eric Biggers, linux-crypto, netdev, devel, linux-nfs

The RC4 algorithm does not fit the sckipher model very well: it is a stream
cipher that combines the key and IV into a single vector, which implies that
using the same key more than once amounts to stream cipher IV reuse, and
therefore catastrophic failure.

So let's replace the remaining legacy users (WEP and TKIP in the staging
tree) to the ARC4 library interface, which does not rely on the crypto API
at all. Also, remove the obsolete RC4-HMAC-MD5 algorithm from the SUNRPC
driver stack.

NOTE: It should not be too difficult to switch the kerberos code over to
the ARC4 library interface as well, given that much of it uses a different
code path already. But we should only do so if we really need to keep this
support around, and it seems that this was only ever intended as a transitional
algorithm for Windows NT/2000 clients.

That leaves no remaining users of the ecb(arc4) skcipher, so we can remove
any implementations as well.

Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Anna Schumaker <anna.schumaker@netapp.com>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Eric Biggers <ebiggers@google.com>
Cc: linux-crypto@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: devel@driverdev.osuosl.org
Cc: linux-nfs@vger.kernel.org

Ard Biesheuvel (7):
  staging/rtl8192e: switch to RC4 library interface
  staging/rtl8192u: switch to RC4 library interface
  SUNRPC: remove RC4-HMAC-MD5 support from KerberosV
  crypto: remove ARC4 support from the skcipher API
  crypto: n2 - remove ecb(arc4) support
  crypto: bcm-iproc - remove ecb(arc4) support
  crypto: tcrypt - remove ecb(arc4) testing/benchmarking support

 crypto/Kconfig                                |  12 -
 crypto/Makefile                               |   1 -
 crypto/arc4.c                                 |  76 -----
 crypto/tcrypt.c                               |  21 +-
 crypto/testmgr.c                              |   7 -
 crypto/testmgr.h                              |  62 ----
 drivers/crypto/bcm/cipher.c                   |  96 +-----
 drivers/crypto/bcm/cipher.h                   |   1 -
 drivers/crypto/bcm/spu.c                      |  23 +-
 drivers/crypto/bcm/spu.h                      |   1 -
 drivers/crypto/bcm/spu2.c                     |  12 +-
 drivers/crypto/bcm/spu2.h                     |   1 -
 drivers/crypto/n2_core.c                      |  46 ---
 drivers/net/wireless/intel/ipw2x00/Kconfig    |   1 -
 drivers/net/wireless/intersil/hostap/Kconfig  |   1 -
 drivers/staging/rtl8192e/Kconfig              |   4 +-
 drivers/staging/rtl8192e/rtllib_crypt_tkip.c  |  70 +----
 drivers/staging/rtl8192e/rtllib_crypt_wep.c   |  72 +----
 drivers/staging/rtl8192u/Kconfig              |   1 +
 .../rtl8192u/ieee80211/ieee80211_crypt_tkip.c |  82 +-----
 .../rtl8192u/ieee80211/ieee80211_crypt_wep.c  |  64 +---
 include/linux/sunrpc/gss_krb5.h               |  11 -
 include/linux/sunrpc/gss_krb5_enctypes.h      |   9 +-
 net/sunrpc/Kconfig                            |   1 -
 net/sunrpc/auth_gss/gss_krb5_crypto.c         | 276 ------------------
 net/sunrpc/auth_gss/gss_krb5_mech.c           |  95 ------
 net/sunrpc/auth_gss/gss_krb5_seal.c           |   1 -
 net/sunrpc/auth_gss/gss_krb5_seqnum.c         |  87 ------
 net/sunrpc/auth_gss/gss_krb5_unseal.c         |   1 -
 net/sunrpc/auth_gss/gss_krb5_wrap.c           |  65 +----
 30 files changed, 78 insertions(+), 1122 deletions(-)
 delete mode 100644 crypto/arc4.c

-- 
2.17.1


^ permalink raw reply	[flat|nested] 17+ messages in thread

* [RFC PATCH 1/7] staging/rtl8192e: switch to RC4 library interface
  2020-07-02 10:19 [RFC PATCH 0/7] crypto: get rid of ecb(arc4) Ard Biesheuvel
@ 2020-07-02 10:19 ` Ard Biesheuvel
  2020-07-02 10:32   ` Greg Kroah-Hartman
  2020-07-02 10:19 ` [RFC PATCH 2/7] staging/rtl8192u: " Ard Biesheuvel
                   ` (5 subsequent siblings)
  6 siblings, 1 reply; 17+ messages in thread
From: Ard Biesheuvel @ 2020-07-02 10:19 UTC (permalink / raw)
  To: linux-kernel
  Cc: Ard Biesheuvel, Herbert Xu, David S. Miller, Greg Kroah-Hartman,
	Trond Myklebust, Anna Schumaker, J. Bruce Fields, Chuck Lever,
	Eric Biggers, linux-crypto, netdev, devel, linux-nfs

Switch to the ARC4 library interface, to remove the pointless
dependency on the skcipher API, from which we will hopefully be
able to drop ecb(arc4) skcipher support.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 drivers/staging/rtl8192e/Kconfig             |  4 +-
 drivers/staging/rtl8192e/rtllib_crypt_tkip.c | 70 ++++---------------
 drivers/staging/rtl8192e/rtllib_crypt_wep.c  | 72 ++++----------------
 3 files changed, 28 insertions(+), 118 deletions(-)

diff --git a/drivers/staging/rtl8192e/Kconfig b/drivers/staging/rtl8192e/Kconfig
index 1007eea6c8fc..4c440bdaaf6e 100644
--- a/drivers/staging/rtl8192e/Kconfig
+++ b/drivers/staging/rtl8192e/Kconfig
@@ -25,7 +25,7 @@ config RTLLIB_CRYPTO_CCMP
 config RTLLIB_CRYPTO_TKIP
 	tristate "Support for rtllib TKIP crypto"
 	depends on RTLLIB
-	select CRYPTO_ARC4
+	select CRYPTO_LIB_ARC4
 	select CRYPTO_MICHAEL_MIC
 	default y
 	help
@@ -35,7 +35,7 @@ config RTLLIB_CRYPTO_TKIP
 
 config RTLLIB_CRYPTO_WEP
 	tristate "Support for rtllib WEP crypto"
-	select CRYPTO_ARC4
+	select CRYPTO_LIB_ARC4
 	depends on RTLLIB
 	default y
 	help
diff --git a/drivers/staging/rtl8192e/rtllib_crypt_tkip.c b/drivers/staging/rtl8192e/rtllib_crypt_tkip.c
index 8d2a58e706d5..8c2ff37b2d3a 100644
--- a/drivers/staging/rtl8192e/rtllib_crypt_tkip.c
+++ b/drivers/staging/rtl8192e/rtllib_crypt_tkip.c
@@ -5,8 +5,9 @@
  * Copyright (c) 2003-2004, Jouni Malinen <jkmaline@cc.hut.fi>
  */
 
+#include <crypto/arc4.h>
 #include <crypto/hash.h>
-#include <crypto/skcipher.h>
+#include <linux/fips.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/slab.h>
@@ -16,7 +17,6 @@
 #include <linux/if_ether.h>
 #include <linux/if_arp.h>
 #include <linux/string.h>
-#include <linux/scatterlist.h>
 #include <linux/crc32.h>
 #include <linux/etherdevice.h>
 
@@ -45,9 +45,9 @@ struct rtllib_tkip_data {
 	u32 dot11RSNAStatsTKIPLocalMICFailures;
 
 	int key_idx;
-	struct crypto_sync_skcipher *rx_tfm_arc4;
+	struct arc4_ctx rx_ctx_arc4;
+	struct arc4_ctx tx_ctx_arc4;
 	struct crypto_shash *rx_tfm_michael;
-	struct crypto_sync_skcipher *tx_tfm_arc4;
 	struct crypto_shash *tx_tfm_michael;
 	/* scratch buffers for virt_to_page() (crypto API) */
 	u8 rx_hdr[16];
@@ -58,16 +58,13 @@ static void *rtllib_tkip_init(int key_idx)
 {
 	struct rtllib_tkip_data *priv;
 
+	if (fips_enabled)
+		return NULL;
+
 	priv = kzalloc(sizeof(*priv), GFP_ATOMIC);
 	if (priv == NULL)
 		goto fail;
 	priv->key_idx = key_idx;
-	priv->tx_tfm_arc4 = crypto_alloc_sync_skcipher("ecb(arc4)", 0, 0);
-	if (IS_ERR(priv->tx_tfm_arc4)) {
-		pr_debug("Could not allocate crypto API arc4\n");
-		priv->tx_tfm_arc4 = NULL;
-		goto fail;
-	}
 
 	priv->tx_tfm_michael = crypto_alloc_shash("michael_mic", 0, 0);
 	if (IS_ERR(priv->tx_tfm_michael)) {
@@ -76,13 +73,6 @@ static void *rtllib_tkip_init(int key_idx)
 		goto fail;
 	}
 
-	priv->rx_tfm_arc4 = crypto_alloc_sync_skcipher("ecb(arc4)", 0, 0);
-	if (IS_ERR(priv->rx_tfm_arc4)) {
-		pr_debug("Could not allocate crypto API arc4\n");
-		priv->rx_tfm_arc4 = NULL;
-		goto fail;
-	}
-
 	priv->rx_tfm_michael = crypto_alloc_shash("michael_mic", 0, 0);
 	if (IS_ERR(priv->rx_tfm_michael)) {
 		pr_debug("Could not allocate crypto API michael_mic\n");
@@ -94,9 +84,7 @@ static void *rtllib_tkip_init(int key_idx)
 fail:
 	if (priv) {
 		crypto_free_shash(priv->tx_tfm_michael);
-		crypto_free_sync_skcipher(priv->tx_tfm_arc4);
 		crypto_free_shash(priv->rx_tfm_michael);
-		crypto_free_sync_skcipher(priv->rx_tfm_arc4);
 		kfree(priv);
 	}
 
@@ -110,11 +98,9 @@ static void rtllib_tkip_deinit(void *priv)
 
 	if (_priv) {
 		crypto_free_shash(_priv->tx_tfm_michael);
-		crypto_free_sync_skcipher(_priv->tx_tfm_arc4);
 		crypto_free_shash(_priv->rx_tfm_michael);
-		crypto_free_sync_skcipher(_priv->rx_tfm_arc4);
 	}
-	kfree(priv);
+	kzfree(priv);
 }
 
 
@@ -289,7 +275,6 @@ static int rtllib_tkip_encrypt(struct sk_buff *skb, int hdr_len, void *priv)
 	int ret = 0;
 	u8 rc4key[16],  *icv;
 	u32 crc;
-	struct scatterlist sg;
 
 	if (skb_headroom(skb) < 8 || skb_tailroom(skb) < 4 ||
 	    skb->len < hdr_len)
@@ -331,8 +316,6 @@ static int rtllib_tkip_encrypt(struct sk_buff *skb, int hdr_len, void *priv)
 	*pos++ = (tkey->tx_iv32 >> 24) & 0xff;
 
 	if (!tcb_desc->bHwSec) {
-		SYNC_SKCIPHER_REQUEST_ON_STACK(req, tkey->tx_tfm_arc4);
-
 		icv = skb_put(skb, 4);
 		crc = ~crc32_le(~0, pos, len);
 		icv[0] = crc;
@@ -340,15 +323,8 @@ static int rtllib_tkip_encrypt(struct sk_buff *skb, int hdr_len, void *priv)
 		icv[2] = crc >> 16;
 		icv[3] = crc >> 24;
 
-		sg_init_one(&sg, pos, len+4);
-
-
-		crypto_sync_skcipher_setkey(tkey->tx_tfm_arc4, rc4key, 16);
-		skcipher_request_set_sync_tfm(req, tkey->tx_tfm_arc4);
-		skcipher_request_set_callback(req, 0, NULL, NULL);
-		skcipher_request_set_crypt(req, &sg, &sg, len + 4, NULL);
-		ret = crypto_skcipher_encrypt(req);
-		skcipher_request_zero(req);
+		arc4_setkey(&tkey->tx_ctx_arc4, rc4key, 16);
+		arc4_crypt(&tkey->tx_ctx_arc4, pos, pos, len + 4);
 	}
 
 	tkey->tx_iv16++;
@@ -376,9 +352,7 @@ static int rtllib_tkip_decrypt(struct sk_buff *skb, int hdr_len, void *priv)
 	u8 rc4key[16];
 	u8 icv[4];
 	u32 crc;
-	struct scatterlist sg;
 	int plen;
-	int err;
 
 	if (skb->len < hdr_len + 8 + 4)
 		return -1;
@@ -414,8 +388,6 @@ static int rtllib_tkip_decrypt(struct sk_buff *skb, int hdr_len, void *priv)
 	pos += 8;
 
 	if (!tcb_desc->bHwSec || (skb->cb[0] == 1)) {
-		SYNC_SKCIPHER_REQUEST_ON_STACK(req, tkey->rx_tfm_arc4);
-
 		if ((iv32 < tkey->rx_iv32 ||
 		    (iv32 == tkey->rx_iv32 && iv16 <= tkey->rx_iv16)) &&
 		    tkey->initialized) {
@@ -439,22 +411,8 @@ static int rtllib_tkip_decrypt(struct sk_buff *skb, int hdr_len, void *priv)
 
 		plen = skb->len - hdr_len - 12;
 
-		sg_init_one(&sg, pos, plen+4);
-
-		crypto_sync_skcipher_setkey(tkey->rx_tfm_arc4, rc4key, 16);
-		skcipher_request_set_sync_tfm(req, tkey->rx_tfm_arc4);
-		skcipher_request_set_callback(req, 0, NULL, NULL);
-		skcipher_request_set_crypt(req, &sg, &sg, plen + 4, NULL);
-		err = crypto_skcipher_decrypt(req);
-		skcipher_request_zero(req);
-		if (err) {
-			if (net_ratelimit()) {
-				netdev_dbg(skb->dev,
-					   "Failed to decrypt received packet from %pM\n",
-					   hdr->addr2);
-			}
-			return -7;
-		}
+		arc4_setkey(&tkey->rx_ctx_arc4, rc4key, 16);
+		arc4_crypt(&tkey->rx_ctx_arc4, pos, pos, plen + 4);
 
 		crc = ~crc32_le(~0, pos, plen);
 		icv[0] = crc;
@@ -657,17 +615,13 @@ static int rtllib_tkip_set_key(void *key, int len, u8 *seq, void *priv)
 	struct rtllib_tkip_data *tkey = priv;
 	int keyidx;
 	struct crypto_shash *tfm = tkey->tx_tfm_michael;
-	struct crypto_sync_skcipher *tfm2 = tkey->tx_tfm_arc4;
 	struct crypto_shash *tfm3 = tkey->rx_tfm_michael;
-	struct crypto_sync_skcipher *tfm4 = tkey->rx_tfm_arc4;
 
 	keyidx = tkey->key_idx;
 	memset(tkey, 0, sizeof(*tkey));
 	tkey->key_idx = keyidx;
 	tkey->tx_tfm_michael = tfm;
-	tkey->tx_tfm_arc4 = tfm2;
 	tkey->rx_tfm_michael = tfm3;
-	tkey->rx_tfm_arc4 = tfm4;
 
 	if (len == TKIP_KEY_LEN) {
 		memcpy(tkey->key, key, TKIP_KEY_LEN);
diff --git a/drivers/staging/rtl8192e/rtllib_crypt_wep.c b/drivers/staging/rtl8192e/rtllib_crypt_wep.c
index b1ea650036d2..7cdd17f907fa 100644
--- a/drivers/staging/rtl8192e/rtllib_crypt_wep.c
+++ b/drivers/staging/rtl8192e/rtllib_crypt_wep.c
@@ -5,7 +5,8 @@
  * Copyright (c) 2002-2004, Jouni Malinen <jkmaline@cc.hut.fi>
  */
 
-#include <crypto/skcipher.h>
+#include <crypto/arc4.h>
+#include <linux/fips.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/slab.h>
@@ -14,7 +15,6 @@
 #include <linux/string.h>
 #include "rtllib.h"
 
-#include <linux/scatterlist.h>
 #include <linux/crc32.h>
 
 struct prism2_wep_data {
@@ -23,8 +23,8 @@ struct prism2_wep_data {
 	u8 key[WEP_KEY_LEN + 1];
 	u8 key_len;
 	u8 key_idx;
-	struct crypto_sync_skcipher *tx_tfm;
-	struct crypto_sync_skcipher *rx_tfm;
+	struct arc4_ctx rx_ctx_arc4;
+	struct arc4_ctx tx_ctx_arc4;
 };
 
 
@@ -32,48 +32,24 @@ static void *prism2_wep_init(int keyidx)
 {
 	struct prism2_wep_data *priv;
 
+	if (fips_enabled)
+		return NULL;
+
 	priv = kzalloc(sizeof(*priv), GFP_ATOMIC);
 	if (priv == NULL)
-		goto fail;
+		return NULL;
 	priv->key_idx = keyidx;
 
-	priv->tx_tfm = crypto_alloc_sync_skcipher("ecb(arc4)", 0, 0);
-	if (IS_ERR(priv->tx_tfm)) {
-		pr_debug("rtllib_crypt_wep: could not allocate crypto API arc4\n");
-		priv->tx_tfm = NULL;
-		goto fail;
-	}
-	priv->rx_tfm = crypto_alloc_sync_skcipher("ecb(arc4)", 0, 0);
-	if (IS_ERR(priv->rx_tfm)) {
-		pr_debug("rtllib_crypt_wep: could not allocate crypto API arc4\n");
-		priv->rx_tfm = NULL;
-		goto fail;
-	}
-
 	/* start WEP IV from a random value */
 	get_random_bytes(&priv->iv, 4);
 
 	return priv;
-
-fail:
-	if (priv) {
-		crypto_free_sync_skcipher(priv->tx_tfm);
-		crypto_free_sync_skcipher(priv->rx_tfm);
-		kfree(priv);
-	}
-	return NULL;
 }
 
 
 static void prism2_wep_deinit(void *priv)
 {
-	struct prism2_wep_data *_priv = priv;
-
-	if (_priv) {
-		crypto_free_sync_skcipher(_priv->tx_tfm);
-		crypto_free_sync_skcipher(_priv->rx_tfm);
-	}
-	kfree(priv);
+	kzfree(priv);
 }
 
 /* Perform WEP encryption on given skb that has at least 4 bytes of headroom
@@ -92,8 +68,6 @@ static int prism2_wep_encrypt(struct sk_buff *skb, int hdr_len, void *priv)
 				    MAX_DEV_ADDR_SIZE);
 	u32 crc;
 	u8 *icv;
-	struct scatterlist sg;
-	int err;
 
 	if (skb_headroom(skb) < 4 || skb_tailroom(skb) < 4 ||
 	    skb->len < hdr_len){
@@ -131,8 +105,6 @@ static int prism2_wep_encrypt(struct sk_buff *skb, int hdr_len, void *priv)
 	memcpy(key + 3, wep->key, wep->key_len);
 
 	if (!tcb_desc->bHwSec) {
-		SYNC_SKCIPHER_REQUEST_ON_STACK(req, wep->tx_tfm);
-
 		/* Append little-endian CRC32 and encrypt it to produce ICV */
 		crc = ~crc32_le(~0, pos, len);
 		icv = skb_put(skb, 4);
@@ -141,14 +113,8 @@ static int prism2_wep_encrypt(struct sk_buff *skb, int hdr_len, void *priv)
 		icv[2] = crc >> 16;
 		icv[3] = crc >> 24;
 
-		sg_init_one(&sg, pos, len+4);
-		crypto_sync_skcipher_setkey(wep->tx_tfm, key, klen);
-		skcipher_request_set_sync_tfm(req, wep->tx_tfm);
-		skcipher_request_set_callback(req, 0, NULL, NULL);
-		skcipher_request_set_crypt(req, &sg, &sg, len + 4, NULL);
-		err = crypto_skcipher_encrypt(req);
-		skcipher_request_zero(req);
-		return err;
+		arc4_setkey(&wep->tx_ctx_arc4, key, klen);
+		arc4_crypt(&wep->tx_ctx_arc4, pos, pos, len + 4);
 	}
 
 	return 0;
@@ -172,8 +138,6 @@ static int prism2_wep_decrypt(struct sk_buff *skb, int hdr_len, void *priv)
 				    MAX_DEV_ADDR_SIZE);
 	u32 crc;
 	u8 icv[4];
-	struct scatterlist sg;
-	int err;
 
 	if (skb->len < hdr_len + 8)
 		return -1;
@@ -195,17 +159,9 @@ static int prism2_wep_decrypt(struct sk_buff *skb, int hdr_len, void *priv)
 	plen = skb->len - hdr_len - 8;
 
 	if (!tcb_desc->bHwSec) {
-		SYNC_SKCIPHER_REQUEST_ON_STACK(req, wep->rx_tfm);
-
-		sg_init_one(&sg, pos, plen+4);
-		crypto_sync_skcipher_setkey(wep->rx_tfm, key, klen);
-		skcipher_request_set_sync_tfm(req, wep->rx_tfm);
-		skcipher_request_set_callback(req, 0, NULL, NULL);
-		skcipher_request_set_crypt(req, &sg, &sg, plen + 4, NULL);
-		err = crypto_skcipher_decrypt(req);
-		skcipher_request_zero(req);
-		if (err)
-			return -7;
+		arc4_setkey(&wep->rx_ctx_arc4, key, klen);
+		arc4_crypt(&wep->rx_ctx_arc4, pos, pos, plen + 4);
+
 		crc = ~crc32_le(~0, pos, plen);
 		icv[0] = crc;
 		icv[1] = crc >> 8;
-- 
2.17.1


^ permalink raw reply related	[flat|nested] 17+ messages in thread

* [RFC PATCH 2/7] staging/rtl8192u: switch to RC4 library interface
  2020-07-02 10:19 [RFC PATCH 0/7] crypto: get rid of ecb(arc4) Ard Biesheuvel
  2020-07-02 10:19 ` [RFC PATCH 1/7] staging/rtl8192e: switch to RC4 library interface Ard Biesheuvel
@ 2020-07-02 10:19 ` Ard Biesheuvel
  2020-07-02 10:32   ` Greg Kroah-Hartman
  2020-07-02 10:19 ` [RFC PATCH 3/7] SUNRPC: remove RC4-HMAC-MD5 support from KerberosV Ard Biesheuvel
                   ` (4 subsequent siblings)
  6 siblings, 1 reply; 17+ messages in thread
From: Ard Biesheuvel @ 2020-07-02 10:19 UTC (permalink / raw)
  To: linux-kernel
  Cc: Ard Biesheuvel, Herbert Xu, David S. Miller, Greg Kroah-Hartman,
	Trond Myklebust, Anna Schumaker, J. Bruce Fields, Chuck Lever,
	Eric Biggers, linux-crypto, netdev, devel, linux-nfs

Switch to the ARC4 library interface, to remove the pointless
dependency on the skcipher API, from which we will hopefully be
able to drop ecb(arc4) skcipher support.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 drivers/staging/rtl8192u/Kconfig                          |  1 +
 drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_tkip.c | 82 ++++----------------
 drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_wep.c  | 64 +++------------
 3 files changed, 27 insertions(+), 120 deletions(-)

diff --git a/drivers/staging/rtl8192u/Kconfig b/drivers/staging/rtl8192u/Kconfig
index 1edca5c304fb..ef883d462d3d 100644
--- a/drivers/staging/rtl8192u/Kconfig
+++ b/drivers/staging/rtl8192u/Kconfig
@@ -8,3 +8,4 @@ config RTL8192U
 	select CRYPTO
 	select CRYPTO_AES
 	select CRYPTO_CCM
+	select CRYPTO_LIB_ARC4
diff --git a/drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_tkip.c b/drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_tkip.c
index ffe624ed0c0c..a315133c20db 100644
--- a/drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_tkip.c
+++ b/drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_tkip.c
@@ -5,6 +5,7 @@
  * Copyright (c) 2003-2004, Jouni Malinen <jkmaline@cc.hut.fi>
  */
 
+#include <linux/fips.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/slab.h>
@@ -17,9 +18,7 @@
 
 #include "ieee80211.h"
 
-#include <crypto/hash.h>
-#include <crypto/skcipher.h>
-	#include <linux/scatterlist.h>
+#include <crypto/arc4.h>
 #include <linux/crc32.h>
 
 MODULE_AUTHOR("Jouni Malinen");
@@ -49,9 +48,9 @@ struct ieee80211_tkip_data {
 
 	int key_idx;
 
-	struct crypto_sync_skcipher *rx_tfm_arc4;
+	struct arc4_ctx rx_ctx_arc4;
+	struct arc4_ctx tx_ctx_arc4;
 	struct crypto_shash *rx_tfm_michael;
-	struct crypto_sync_skcipher *tx_tfm_arc4;
 	struct crypto_shash *tx_tfm_michael;
 
 	/* scratch buffers for virt_to_page() (crypto API) */
@@ -62,19 +61,14 @@ static void *ieee80211_tkip_init(int key_idx)
 {
 	struct ieee80211_tkip_data *priv;
 
+	if (fips_enabled)
+		return NULL;
+
 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 	if (!priv)
 		goto fail;
 	priv->key_idx = key_idx;
 
-	priv->tx_tfm_arc4 = crypto_alloc_sync_skcipher("ecb(arc4)", 0, 0);
-	if (IS_ERR(priv->tx_tfm_arc4)) {
-		printk(KERN_DEBUG "ieee80211_crypt_tkip: could not allocate "
-				"crypto API arc4\n");
-		priv->tx_tfm_arc4 = NULL;
-		goto fail;
-	}
-
 	priv->tx_tfm_michael = crypto_alloc_shash("michael_mic", 0, 0);
 	if (IS_ERR(priv->tx_tfm_michael)) {
 		printk(KERN_DEBUG "ieee80211_crypt_tkip: could not allocate "
@@ -83,14 +77,6 @@ static void *ieee80211_tkip_init(int key_idx)
 		goto fail;
 	}
 
-	priv->rx_tfm_arc4 = crypto_alloc_sync_skcipher("ecb(arc4)", 0, 0);
-	if (IS_ERR(priv->rx_tfm_arc4)) {
-		printk(KERN_DEBUG "ieee80211_crypt_tkip: could not allocate "
-				"crypto API arc4\n");
-		priv->rx_tfm_arc4 = NULL;
-		goto fail;
-	}
-
 	priv->rx_tfm_michael = crypto_alloc_shash("michael_mic", 0, 0);
 	if (IS_ERR(priv->rx_tfm_michael)) {
 		printk(KERN_DEBUG "ieee80211_crypt_tkip: could not allocate "
@@ -104,9 +90,7 @@ static void *ieee80211_tkip_init(int key_idx)
 fail:
 	if (priv) {
 		crypto_free_shash(priv->tx_tfm_michael);
-		crypto_free_sync_skcipher(priv->tx_tfm_arc4);
 		crypto_free_shash(priv->rx_tfm_michael);
-		crypto_free_sync_skcipher(priv->rx_tfm_arc4);
 		kfree(priv);
 	}
 
@@ -120,11 +104,9 @@ static void ieee80211_tkip_deinit(void *priv)
 
 	if (_priv) {
 		crypto_free_shash(_priv->tx_tfm_michael);
-		crypto_free_sync_skcipher(_priv->tx_tfm_arc4);
 		crypto_free_shash(_priv->rx_tfm_michael);
-		crypto_free_sync_skcipher(_priv->rx_tfm_arc4);
 	}
-	kfree(priv);
+	kzfree(priv);
 }
 
 
@@ -290,10 +272,8 @@ static int ieee80211_tkip_encrypt(struct sk_buff *skb, int hdr_len, void *priv)
 	u8 *pos;
 	struct rtl_80211_hdr_4addr *hdr;
 	struct cb_desc *tcb_desc = (struct cb_desc *)(skb->cb + MAX_DEV_ADDR_SIZE);
-	int ret = 0;
 	u8 rc4key[16],  *icv;
 	u32 crc;
-	struct scatterlist sg;
 
 	if (skb_headroom(skb) < 8 || skb_tailroom(skb) < 4 ||
 	    skb->len < hdr_len)
@@ -334,21 +314,15 @@ static int ieee80211_tkip_encrypt(struct sk_buff *skb, int hdr_len, void *priv)
 	*pos++ = (tkey->tx_iv32 >> 24) & 0xff;
 
 	if (!tcb_desc->bHwSec) {
-		SYNC_SKCIPHER_REQUEST_ON_STACK(req, tkey->tx_tfm_arc4);
-
 		icv = skb_put(skb, 4);
 		crc = ~crc32_le(~0, pos, len);
 		icv[0] = crc;
 		icv[1] = crc >> 8;
 		icv[2] = crc >> 16;
 		icv[3] = crc >> 24;
-		crypto_sync_skcipher_setkey(tkey->tx_tfm_arc4, rc4key, 16);
-		sg_init_one(&sg, pos, len + 4);
-		skcipher_request_set_sync_tfm(req, tkey->tx_tfm_arc4);
-		skcipher_request_set_callback(req, 0, NULL, NULL);
-		skcipher_request_set_crypt(req, &sg, &sg, len + 4, NULL);
-		ret = crypto_skcipher_encrypt(req);
-		skcipher_request_zero(req);
+
+		arc4_setkey(&tkey->tx_ctx_arc4, rc4key, 16);
+		arc4_crypt(&tkey->tx_ctx_arc4, pos, pos, len + 4);
 	}
 
 	tkey->tx_iv16++;
@@ -357,12 +331,7 @@ static int ieee80211_tkip_encrypt(struct sk_buff *skb, int hdr_len, void *priv)
 		tkey->tx_iv32++;
 	}
 
-	if (!tcb_desc->bHwSec)
-		return ret;
-	else
-		return 0;
-
-
+	return 0;
 }
 
 static int ieee80211_tkip_decrypt(struct sk_buff *skb, int hdr_len, void *priv)
@@ -376,9 +345,7 @@ static int ieee80211_tkip_decrypt(struct sk_buff *skb, int hdr_len, void *priv)
 	u8 rc4key[16];
 	u8 icv[4];
 	u32 crc;
-	struct scatterlist sg;
 	int plen;
-	int err;
 
 	if (skb->len < hdr_len + 8 + 4)
 		return -1;
@@ -412,8 +379,6 @@ static int ieee80211_tkip_decrypt(struct sk_buff *skb, int hdr_len, void *priv)
 	pos += 8;
 
 	if (!tcb_desc->bHwSec) {
-		SYNC_SKCIPHER_REQUEST_ON_STACK(req, tkey->rx_tfm_arc4);
-
 		if (iv32 < tkey->rx_iv32 ||
 		(iv32 == tkey->rx_iv32 && iv16 <= tkey->rx_iv16)) {
 			if (net_ratelimit()) {
@@ -434,23 +399,8 @@ static int ieee80211_tkip_decrypt(struct sk_buff *skb, int hdr_len, void *priv)
 
 		plen = skb->len - hdr_len - 12;
 
-		crypto_sync_skcipher_setkey(tkey->rx_tfm_arc4, rc4key, 16);
-		sg_init_one(&sg, pos, plen + 4);
-
-		skcipher_request_set_sync_tfm(req, tkey->rx_tfm_arc4);
-		skcipher_request_set_callback(req, 0, NULL, NULL);
-		skcipher_request_set_crypt(req, &sg, &sg, plen + 4, NULL);
-
-		err = crypto_skcipher_decrypt(req);
-		skcipher_request_zero(req);
-		if (err) {
-			if (net_ratelimit()) {
-				netdev_dbg(skb->dev, "TKIP: failed to decrypt "
-						"received packet from %pM\n",
-						hdr->addr2);
-			}
-			return -7;
-		}
+		arc4_setkey(&tkey->rx_ctx_arc4, rc4key, 16);
+		arc4_crypt(&tkey->rx_ctx_arc4, pos, pos, plen + 4);
 
 		crc = ~crc32_le(~0, pos, plen);
 		icv[0] = crc;
@@ -655,17 +605,13 @@ static int ieee80211_tkip_set_key(void *key, int len, u8 *seq, void *priv)
 	struct ieee80211_tkip_data *tkey = priv;
 	int keyidx;
 	struct crypto_shash *tfm = tkey->tx_tfm_michael;
-	struct crypto_sync_skcipher *tfm2 = tkey->tx_tfm_arc4;
 	struct crypto_shash *tfm3 = tkey->rx_tfm_michael;
-	struct crypto_sync_skcipher *tfm4 = tkey->rx_tfm_arc4;
 
 	keyidx = tkey->key_idx;
 	memset(tkey, 0, sizeof(*tkey));
 	tkey->key_idx = keyidx;
 	tkey->tx_tfm_michael = tfm;
-	tkey->tx_tfm_arc4 = tfm2;
 	tkey->rx_tfm_michael = tfm3;
-	tkey->rx_tfm_arc4 = tfm4;
 
 	if (len == TKIP_KEY_LEN) {
 		memcpy(tkey->key, key, TKIP_KEY_LEN);
diff --git a/drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_wep.c b/drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_wep.c
index 26482c3dcd1c..1c56e2d03aae 100644
--- a/drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_wep.c
+++ b/drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_wep.c
@@ -5,6 +5,7 @@
  * Copyright (c) 2002-2004, Jouni Malinen <jkmaline@cc.hut.fi>
  */
 
+#include <linux/fips.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/slab.h>
@@ -14,8 +15,7 @@
 
 #include "ieee80211.h"
 
-#include <crypto/skcipher.h>
-#include <linux/scatterlist.h>
+#include <crypto/arc4.h>
 #include <linux/crc32.h>
 
 MODULE_AUTHOR("Jouni Malinen");
@@ -28,8 +28,8 @@ struct prism2_wep_data {
 	u8 key[WEP_KEY_LEN + 1];
 	u8 key_len;
 	u8 key_idx;
-	struct crypto_sync_skcipher *tx_tfm;
-	struct crypto_sync_skcipher *rx_tfm;
+	struct arc4_ctx rx_ctx_arc4;
+	struct arc4_ctx tx_ctx_arc4;
 };
 
 
@@ -37,39 +37,24 @@ static void *prism2_wep_init(int keyidx)
 {
 	struct prism2_wep_data *priv;
 
+	if (fips_enabled)
+		return NULL;
+
 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 	if (!priv)
 		return NULL;
 	priv->key_idx = keyidx;
 
-	priv->tx_tfm = crypto_alloc_sync_skcipher("ecb(arc4)", 0, 0);
-	if (IS_ERR(priv->tx_tfm))
-		goto free_priv;
-	priv->rx_tfm = crypto_alloc_sync_skcipher("ecb(arc4)", 0, 0);
-	if (IS_ERR(priv->rx_tfm))
-		goto free_tx;
-
 	/* start WEP IV from a random value */
 	get_random_bytes(&priv->iv, 4);
 
 	return priv;
-free_tx:
-	crypto_free_sync_skcipher(priv->tx_tfm);
-free_priv:
-	kfree(priv);
-	return NULL;
 }
 
 
 static void prism2_wep_deinit(void *priv)
 {
-	struct prism2_wep_data *_priv = priv;
-
-	if (_priv) {
-		crypto_free_sync_skcipher(_priv->tx_tfm);
-		crypto_free_sync_skcipher(_priv->rx_tfm);
-	}
-	kfree(priv);
+	kzfree(priv);
 }
 
 /* Perform WEP encryption on given skb that has at least 4 bytes of headroom
@@ -87,8 +72,6 @@ static int prism2_wep_encrypt(struct sk_buff *skb, int hdr_len, void *priv)
 	struct cb_desc *tcb_desc = (struct cb_desc *)(skb->cb + MAX_DEV_ADDR_SIZE);
 	u32 crc;
 	u8 *icv;
-	struct scatterlist sg;
-	int err;
 
 	if (skb_headroom(skb) < 4 || skb_tailroom(skb) < 4 ||
 	    skb->len < hdr_len)
@@ -124,8 +107,6 @@ static int prism2_wep_encrypt(struct sk_buff *skb, int hdr_len, void *priv)
 	memcpy(key + 3, wep->key, wep->key_len);
 
 	if (!tcb_desc->bHwSec) {
-		SYNC_SKCIPHER_REQUEST_ON_STACK(req, wep->tx_tfm);
-
 		/* Append little-endian CRC32 and encrypt it to produce ICV */
 		crc = ~crc32_le(~0, pos, len);
 		icv = skb_put(skb, 4);
@@ -134,16 +115,8 @@ static int prism2_wep_encrypt(struct sk_buff *skb, int hdr_len, void *priv)
 		icv[2] = crc >> 16;
 		icv[3] = crc >> 24;
 
-		crypto_sync_skcipher_setkey(wep->tx_tfm, key, klen);
-		sg_init_one(&sg, pos, len + 4);
-
-		skcipher_request_set_sync_tfm(req, wep->tx_tfm);
-		skcipher_request_set_callback(req, 0, NULL, NULL);
-		skcipher_request_set_crypt(req, &sg, &sg, len + 4, NULL);
-
-		err = crypto_skcipher_encrypt(req);
-		skcipher_request_zero(req);
-		return err;
+		arc4_setkey(&wep->tx_ctx_arc4, key, klen);
+		arc4_crypt(&wep->tx_ctx_arc4, pos, pos, len + 4);
 	}
 
 	return 0;
@@ -166,8 +139,6 @@ static int prism2_wep_decrypt(struct sk_buff *skb, int hdr_len, void *priv)
 	struct cb_desc *tcb_desc = (struct cb_desc *)(skb->cb + MAX_DEV_ADDR_SIZE);
 	u32 crc;
 	u8 icv[4];
-	struct scatterlist sg;
-	int err;
 
 	if (skb->len < hdr_len + 8)
 		return -1;
@@ -189,19 +160,8 @@ static int prism2_wep_decrypt(struct sk_buff *skb, int hdr_len, void *priv)
 	plen = skb->len - hdr_len - 8;
 
 	if (!tcb_desc->bHwSec) {
-		SYNC_SKCIPHER_REQUEST_ON_STACK(req, wep->rx_tfm);
-
-		crypto_sync_skcipher_setkey(wep->rx_tfm, key, klen);
-		sg_init_one(&sg, pos, plen + 4);
-
-		skcipher_request_set_sync_tfm(req, wep->rx_tfm);
-		skcipher_request_set_callback(req, 0, NULL, NULL);
-		skcipher_request_set_crypt(req, &sg, &sg, plen + 4, NULL);
-
-		err = crypto_skcipher_decrypt(req);
-		skcipher_request_zero(req);
-		if (err)
-			return -7;
+		arc4_setkey(&wep->rx_ctx_arc4, key, klen);
+		arc4_crypt(&wep->rx_ctx_arc4, pos, pos, plen + 4);
 
 		crc = ~crc32_le(~0, pos, plen);
 		icv[0] = crc;
-- 
2.17.1


^ permalink raw reply related	[flat|nested] 17+ messages in thread

* [RFC PATCH 3/7] SUNRPC: remove RC4-HMAC-MD5 support from KerberosV
  2020-07-02 10:19 [RFC PATCH 0/7] crypto: get rid of ecb(arc4) Ard Biesheuvel
  2020-07-02 10:19 ` [RFC PATCH 1/7] staging/rtl8192e: switch to RC4 library interface Ard Biesheuvel
  2020-07-02 10:19 ` [RFC PATCH 2/7] staging/rtl8192u: " Ard Biesheuvel
@ 2020-07-02 10:19 ` Ard Biesheuvel
  2020-07-02 15:49   ` J. Bruce Fields
  2020-07-02 10:19 ` [RFC PATCH 4/7] crypto: remove ARC4 support from the skcipher API Ard Biesheuvel
                   ` (3 subsequent siblings)
  6 siblings, 1 reply; 17+ messages in thread
From: Ard Biesheuvel @ 2020-07-02 10:19 UTC (permalink / raw)
  To: linux-kernel
  Cc: Ard Biesheuvel, Herbert Xu, David S. Miller, Greg Kroah-Hartman,
	Trond Myklebust, Anna Schumaker, J. Bruce Fields, Chuck Lever,
	Eric Biggers, linux-crypto, netdev, devel, linux-nfs

The RC4-HMAC-MD5 KerberosV algorithm is based on RFC 4757 [0], which
was specifically issued for interoperability with Windows 2000, but was
never intended to receive the same level of support. The RFC says

  The IETF Kerberos community supports publishing this specification as
  an informational document in order to describe this widely
  implemented technology.  However, while these encryption types
  provide the operations necessary to implement the base Kerberos
  specification [RFC4120], they do not provide all the required
  operations in the Kerberos cryptography framework [RFC3961].  As a
  result, it is not generally possible to implement potential
  extensions to Kerberos using these encryption types.  The Kerberos
  encryption type negotiation mechanism [RFC4537] provides one approach
  for using such extensions even when a Kerberos infrastructure uses
  long-term RC4 keys.  Because this specification does not implement
  operations required by RFC 3961 and because of security concerns with
  the use of RC4 and MD4 discussed in Section 8, this specification is
  not appropriate for publication on the standards track.

  The RC4-HMAC encryption types are used to ease upgrade of existing
  Windows NT environments, provide strong cryptography (128-bit key
  lengths), and provide exportable (meet United States government
  export restriction requirements) encryption.  This document describes
  the implementation of those encryption types.

Furthermore, this RFC was re-classified as 'historic' by RFC 8429 [1] in
2018, stating that 'none of the encryption types it specifies should be
used'

Note that other outdated algorithms are left in place (some of which are
guarded by CONFIG_SUNRPC_DISABLE_INSECURE_ENCTYPES), so this should only
adversely affect interoperability with Windows NT/2000 systems that have
not received any updates since 2008 (but are connected to a network
nonetheless)

[0] https://tools.ietf.org/html/rfc4757
[1] https://tools.ietf.org/html/rfc8429

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 include/linux/sunrpc/gss_krb5.h          |  11 -
 include/linux/sunrpc/gss_krb5_enctypes.h |   9 +-
 net/sunrpc/Kconfig                       |   1 -
 net/sunrpc/auth_gss/gss_krb5_crypto.c    | 276 --------------------
 net/sunrpc/auth_gss/gss_krb5_mech.c      |  95 -------
 net/sunrpc/auth_gss/gss_krb5_seal.c      |   1 -
 net/sunrpc/auth_gss/gss_krb5_seqnum.c    |  87 ------
 net/sunrpc/auth_gss/gss_krb5_unseal.c    |   1 -
 net/sunrpc/auth_gss/gss_krb5_wrap.c      |  65 +----
 9 files changed, 16 insertions(+), 530 deletions(-)

diff --git a/include/linux/sunrpc/gss_krb5.h b/include/linux/sunrpc/gss_krb5.h
index e8f8ffe7448b..91f43d86879d 100644
--- a/include/linux/sunrpc/gss_krb5.h
+++ b/include/linux/sunrpc/gss_krb5.h
@@ -141,14 +141,12 @@ enum sgn_alg {
 	SGN_ALG_MD2_5 = 0x0001,
 	SGN_ALG_DES_MAC = 0x0002,
 	SGN_ALG_3 = 0x0003,		/* not published */
-	SGN_ALG_HMAC_MD5 = 0x0011,	/* microsoft w2k; no support */
 	SGN_ALG_HMAC_SHA1_DES3_KD = 0x0004
 };
 enum seal_alg {
 	SEAL_ALG_NONE = 0xffff,
 	SEAL_ALG_DES = 0x0000,
 	SEAL_ALG_1 = 0x0001,		/* not published */
-	SEAL_ALG_MICROSOFT_RC4 = 0x0010,/* microsoft w2k; no support */
 	SEAL_ALG_DES3KD = 0x0002
 };
 
@@ -316,14 +314,5 @@ gss_krb5_aes_decrypt(struct krb5_ctx *kctx, u32 offset, u32 len,
 		     struct xdr_buf *buf, u32 *plainoffset,
 		     u32 *plainlen);
 
-int
-krb5_rc4_setup_seq_key(struct krb5_ctx *kctx,
-		       struct crypto_sync_skcipher *cipher,
-		       unsigned char *cksum);
-
-int
-krb5_rc4_setup_enc_key(struct krb5_ctx *kctx,
-		       struct crypto_sync_skcipher *cipher,
-		       s32 seqnum);
 void
 gss_krb5_make_confounder(char *p, u32 conflen);
diff --git a/include/linux/sunrpc/gss_krb5_enctypes.h b/include/linux/sunrpc/gss_krb5_enctypes.h
index 981c89cef19d..87eea679d750 100644
--- a/include/linux/sunrpc/gss_krb5_enctypes.h
+++ b/include/linux/sunrpc/gss_krb5_enctypes.h
@@ -13,15 +13,13 @@
 #ifdef CONFIG_SUNRPC_DISABLE_INSECURE_ENCTYPES
 
 /*
- * NB: This list includes encryption types that were deprecated
- * by RFC 8429 (DES3_CBC_SHA1 and ARCFOUR_HMAC).
+ * NB: This list includes DES3_CBC_SHA1, which was deprecated by RFC 8429.
  *
  * ENCTYPE_AES256_CTS_HMAC_SHA1_96
  * ENCTYPE_AES128_CTS_HMAC_SHA1_96
  * ENCTYPE_DES3_CBC_SHA1
- * ENCTYPE_ARCFOUR_HMAC
  */
-#define KRB5_SUPPORTED_ENCTYPES "18,17,16,23"
+#define KRB5_SUPPORTED_ENCTYPES "18,17,16"
 
 #else	/* CONFIG_SUNRPC_DISABLE_INSECURE_ENCTYPES */
 
@@ -32,12 +30,11 @@
  * ENCTYPE_AES256_CTS_HMAC_SHA1_96
  * ENCTYPE_AES128_CTS_HMAC_SHA1_96
  * ENCTYPE_DES3_CBC_SHA1
- * ENCTYPE_ARCFOUR_HMAC
  * ENCTYPE_DES_CBC_MD5
  * ENCTYPE_DES_CBC_CRC
  * ENCTYPE_DES_CBC_MD4
  */
-#define KRB5_SUPPORTED_ENCTYPES "18,17,16,23,3,1,2"
+#define KRB5_SUPPORTED_ENCTYPES "18,17,16,3,1,2"
 
 #endif	/* CONFIG_SUNRPC_DISABLE_INSECURE_ENCTYPES */
 
diff --git a/net/sunrpc/Kconfig b/net/sunrpc/Kconfig
index 3bcf985507be..bbbb5af0af13 100644
--- a/net/sunrpc/Kconfig
+++ b/net/sunrpc/Kconfig
@@ -21,7 +21,6 @@ config RPCSEC_GSS_KRB5
 	depends on SUNRPC && CRYPTO
 	depends on CRYPTO_MD5 && CRYPTO_DES && CRYPTO_CBC && CRYPTO_CTS
 	depends on CRYPTO_ECB && CRYPTO_HMAC && CRYPTO_SHA1 && CRYPTO_AES
-	depends on CRYPTO_ARC4
 	default y
 	select SUNRPC_GSS
 	help
diff --git a/net/sunrpc/auth_gss/gss_krb5_crypto.c b/net/sunrpc/auth_gss/gss_krb5_crypto.c
index e7180da1fc6a..634b6c6e0dcb 100644
--- a/net/sunrpc/auth_gss/gss_krb5_crypto.c
+++ b/net/sunrpc/auth_gss/gss_krb5_crypto.c
@@ -138,135 +138,6 @@ checksummer(struct scatterlist *sg, void *data)
 	return crypto_ahash_update(req);
 }
 
-static int
-arcfour_hmac_md5_usage_to_salt(unsigned int usage, u8 salt[4])
-{
-	unsigned int ms_usage;
-
-	switch (usage) {
-	case KG_USAGE_SIGN:
-		ms_usage = 15;
-		break;
-	case KG_USAGE_SEAL:
-		ms_usage = 13;
-		break;
-	default:
-		return -EINVAL;
-	}
-	salt[0] = (ms_usage >> 0) & 0xff;
-	salt[1] = (ms_usage >> 8) & 0xff;
-	salt[2] = (ms_usage >> 16) & 0xff;
-	salt[3] = (ms_usage >> 24) & 0xff;
-
-	return 0;
-}
-
-static u32
-make_checksum_hmac_md5(struct krb5_ctx *kctx, char *header, int hdrlen,
-		       struct xdr_buf *body, int body_offset, u8 *cksumkey,
-		       unsigned int usage, struct xdr_netobj *cksumout)
-{
-	struct scatterlist              sg[1];
-	int err = -1;
-	u8 *checksumdata;
-	u8 *rc4salt;
-	struct crypto_ahash *md5;
-	struct crypto_ahash *hmac_md5;
-	struct ahash_request *req;
-
-	if (cksumkey == NULL)
-		return GSS_S_FAILURE;
-
-	if (cksumout->len < kctx->gk5e->cksumlength) {
-		dprintk("%s: checksum buffer length, %u, too small for %s\n",
-			__func__, cksumout->len, kctx->gk5e->name);
-		return GSS_S_FAILURE;
-	}
-
-	rc4salt = kmalloc_array(4, sizeof(*rc4salt), GFP_NOFS);
-	if (!rc4salt)
-		return GSS_S_FAILURE;
-
-	if (arcfour_hmac_md5_usage_to_salt(usage, rc4salt)) {
-		dprintk("%s: invalid usage value %u\n", __func__, usage);
-		goto out_free_rc4salt;
-	}
-
-	checksumdata = kmalloc(GSS_KRB5_MAX_CKSUM_LEN, GFP_NOFS);
-	if (!checksumdata)
-		goto out_free_rc4salt;
-
-	md5 = crypto_alloc_ahash("md5", 0, CRYPTO_ALG_ASYNC);
-	if (IS_ERR(md5))
-		goto out_free_cksum;
-
-	hmac_md5 = crypto_alloc_ahash(kctx->gk5e->cksum_name, 0,
-				      CRYPTO_ALG_ASYNC);
-	if (IS_ERR(hmac_md5))
-		goto out_free_md5;
-
-	req = ahash_request_alloc(md5, GFP_NOFS);
-	if (!req)
-		goto out_free_hmac_md5;
-
-	ahash_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP, NULL, NULL);
-
-	err = crypto_ahash_init(req);
-	if (err)
-		goto out;
-	sg_init_one(sg, rc4salt, 4);
-	ahash_request_set_crypt(req, sg, NULL, 4);
-	err = crypto_ahash_update(req);
-	if (err)
-		goto out;
-
-	sg_init_one(sg, header, hdrlen);
-	ahash_request_set_crypt(req, sg, NULL, hdrlen);
-	err = crypto_ahash_update(req);
-	if (err)
-		goto out;
-	err = xdr_process_buf(body, body_offset, body->len - body_offset,
-			      checksummer, req);
-	if (err)
-		goto out;
-	ahash_request_set_crypt(req, NULL, checksumdata, 0);
-	err = crypto_ahash_final(req);
-	if (err)
-		goto out;
-
-	ahash_request_free(req);
-	req = ahash_request_alloc(hmac_md5, GFP_NOFS);
-	if (!req)
-		goto out_free_hmac_md5;
-
-	ahash_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP, NULL, NULL);
-
-	err = crypto_ahash_setkey(hmac_md5, cksumkey, kctx->gk5e->keylength);
-	if (err)
-		goto out;
-
-	sg_init_one(sg, checksumdata, crypto_ahash_digestsize(md5));
-	ahash_request_set_crypt(req, sg, checksumdata,
-				crypto_ahash_digestsize(md5));
-	err = crypto_ahash_digest(req);
-	if (err)
-		goto out;
-
-	memcpy(cksumout->data, checksumdata, kctx->gk5e->cksumlength);
-	cksumout->len = kctx->gk5e->cksumlength;
-out:
-	ahash_request_free(req);
-out_free_hmac_md5:
-	crypto_free_ahash(hmac_md5);
-out_free_md5:
-	crypto_free_ahash(md5);
-out_free_cksum:
-	kfree(checksumdata);
-out_free_rc4salt:
-	kfree(rc4salt);
-	return err ? GSS_S_FAILURE : 0;
-}
-
 /*
  * checksum the plaintext data and hdrlen bytes of the token header
  * The checksum is performed over the first 8 bytes of the
@@ -284,11 +155,6 @@ make_checksum(struct krb5_ctx *kctx, char *header, int hdrlen,
 	u8 *checksumdata;
 	unsigned int checksumlen;
 
-	if (kctx->gk5e->ctype == CKSUMTYPE_HMAC_MD5_ARCFOUR)
-		return make_checksum_hmac_md5(kctx, header, hdrlen,
-					      body, body_offset,
-					      cksumkey, usage, cksumout);
-
 	if (cksumout->len < kctx->gk5e->cksumlength) {
 		dprintk("%s: checksum buffer length, %u, too small for %s\n",
 			__func__, cksumout->len, kctx->gk5e->name);
@@ -942,145 +808,3 @@ gss_krb5_aes_decrypt(struct krb5_ctx *kctx, u32 offset, u32 len,
 		ret = GSS_S_FAILURE;
 	return ret;
 }
-
-/*
- * Compute Kseq given the initial session key and the checksum.
- * Set the key of the given cipher.
- */
-int
-krb5_rc4_setup_seq_key(struct krb5_ctx *kctx,
-		       struct crypto_sync_skcipher *cipher,
-		       unsigned char *cksum)
-{
-	struct crypto_shash *hmac;
-	struct shash_desc *desc;
-	u8 Kseq[GSS_KRB5_MAX_KEYLEN];
-	u32 zeroconstant = 0;
-	int err;
-
-	dprintk("%s: entered\n", __func__);
-
-	hmac = crypto_alloc_shash(kctx->gk5e->cksum_name, 0, 0);
-	if (IS_ERR(hmac)) {
-		dprintk("%s: error %ld, allocating hash '%s'\n",
-			__func__, PTR_ERR(hmac), kctx->gk5e->cksum_name);
-		return PTR_ERR(hmac);
-	}
-
-	desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(hmac),
-		       GFP_NOFS);
-	if (!desc) {
-		dprintk("%s: failed to allocate shash descriptor for '%s'\n",
-			__func__, kctx->gk5e->cksum_name);
-		crypto_free_shash(hmac);
-		return -ENOMEM;
-	}
-
-	desc->tfm = hmac;
-
-	/* Compute intermediate Kseq from session key */
-	err = crypto_shash_setkey(hmac, kctx->Ksess, kctx->gk5e->keylength);
-	if (err)
-		goto out_err;
-
-	err = crypto_shash_digest(desc, (u8 *)&zeroconstant, 4, Kseq);
-	if (err)
-		goto out_err;
-
-	/* Compute final Kseq from the checksum and intermediate Kseq */
-	err = crypto_shash_setkey(hmac, Kseq, kctx->gk5e->keylength);
-	if (err)
-		goto out_err;
-
-	err = crypto_shash_digest(desc, cksum, 8, Kseq);
-	if (err)
-		goto out_err;
-
-	err = crypto_sync_skcipher_setkey(cipher, Kseq, kctx->gk5e->keylength);
-	if (err)
-		goto out_err;
-
-	err = 0;
-
-out_err:
-	kzfree(desc);
-	crypto_free_shash(hmac);
-	dprintk("%s: returning %d\n", __func__, err);
-	return err;
-}
-
-/*
- * Compute Kcrypt given the initial session key and the plaintext seqnum.
- * Set the key of cipher kctx->enc.
- */
-int
-krb5_rc4_setup_enc_key(struct krb5_ctx *kctx,
-		       struct crypto_sync_skcipher *cipher,
-		       s32 seqnum)
-{
-	struct crypto_shash *hmac;
-	struct shash_desc *desc;
-	u8 Kcrypt[GSS_KRB5_MAX_KEYLEN];
-	u8 zeroconstant[4] = {0};
-	u8 seqnumarray[4];
-	int err, i;
-
-	dprintk("%s: entered, seqnum %u\n", __func__, seqnum);
-
-	hmac = crypto_alloc_shash(kctx->gk5e->cksum_name, 0, 0);
-	if (IS_ERR(hmac)) {
-		dprintk("%s: error %ld, allocating hash '%s'\n",
-			__func__, PTR_ERR(hmac), kctx->gk5e->cksum_name);
-		return PTR_ERR(hmac);
-	}
-
-	desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(hmac),
-		       GFP_NOFS);
-	if (!desc) {
-		dprintk("%s: failed to allocate shash descriptor for '%s'\n",
-			__func__, kctx->gk5e->cksum_name);
-		crypto_free_shash(hmac);
-		return -ENOMEM;
-	}
-
-	desc->tfm = hmac;
-
-	/* Compute intermediate Kcrypt from session key */
-	for (i = 0; i < kctx->gk5e->keylength; i++)
-		Kcrypt[i] = kctx->Ksess[i] ^ 0xf0;
-
-	err = crypto_shash_setkey(hmac, Kcrypt, kctx->gk5e->keylength);
-	if (err)
-		goto out_err;
-
-	err = crypto_shash_digest(desc, zeroconstant, 4, Kcrypt);
-	if (err)
-		goto out_err;
-
-	/* Compute final Kcrypt from the seqnum and intermediate Kcrypt */
-	err = crypto_shash_setkey(hmac, Kcrypt, kctx->gk5e->keylength);
-	if (err)
-		goto out_err;
-
-	seqnumarray[0] = (unsigned char) ((seqnum >> 24) & 0xff);
-	seqnumarray[1] = (unsigned char) ((seqnum >> 16) & 0xff);
-	seqnumarray[2] = (unsigned char) ((seqnum >> 8) & 0xff);
-	seqnumarray[3] = (unsigned char) ((seqnum >> 0) & 0xff);
-
-	err = crypto_shash_digest(desc, seqnumarray, 4, Kcrypt);
-	if (err)
-		goto out_err;
-
-	err = crypto_sync_skcipher_setkey(cipher, Kcrypt,
-					  kctx->gk5e->keylength);
-	if (err)
-		goto out_err;
-
-	err = 0;
-
-out_err:
-	kzfree(desc);
-	crypto_free_shash(hmac);
-	dprintk("%s: returning %d\n", __func__, err);
-	return err;
-}
diff --git a/net/sunrpc/auth_gss/gss_krb5_mech.c b/net/sunrpc/auth_gss/gss_krb5_mech.c
index 75b3c2e9e8f8..ae9acf3a7389 100644
--- a/net/sunrpc/auth_gss/gss_krb5_mech.c
+++ b/net/sunrpc/auth_gss/gss_krb5_mech.c
@@ -51,27 +51,6 @@ static const struct gss_krb5_enctype supported_gss_krb5_enctypes[] = {
 	  .keyed_cksum = 0,
 	},
 #endif	/* CONFIG_SUNRPC_DISABLE_INSECURE_ENCTYPES */
-	/*
-	 * RC4-HMAC
-	 */
-	{
-	  .etype = ENCTYPE_ARCFOUR_HMAC,
-	  .ctype = CKSUMTYPE_HMAC_MD5_ARCFOUR,
-	  .name = "rc4-hmac",
-	  .encrypt_name = "ecb(arc4)",
-	  .cksum_name = "hmac(md5)",
-	  .encrypt = krb5_encrypt,
-	  .decrypt = krb5_decrypt,
-	  .mk_key = NULL,
-	  .signalg = SGN_ALG_HMAC_MD5,
-	  .sealalg = SEAL_ALG_MICROSOFT_RC4,
-	  .keybytes = 16,
-	  .keylength = 16,
-	  .blocksize = 1,
-	  .conflen = 8,
-	  .cksumlength = 8,
-	  .keyed_cksum = 1,
-	},
 	/*
 	 * 3DES
 	 */
@@ -401,78 +380,6 @@ context_derive_keys_des3(struct krb5_ctx *ctx, gfp_t gfp_mask)
 	return -EINVAL;
 }
 
-/*
- * Note that RC4 depends on deriving keys using the sequence
- * number or the checksum of a token.  Therefore, the final keys
- * cannot be calculated until the token is being constructed!
- */
-static int
-context_derive_keys_rc4(struct krb5_ctx *ctx)
-{
-	struct crypto_shash *hmac;
-	char sigkeyconstant[] = "signaturekey";
-	int slen = strlen(sigkeyconstant) + 1;	/* include null terminator */
-	struct shash_desc *desc;
-	int err;
-
-	dprintk("RPC:       %s: entered\n", __func__);
-	/*
-	 * derive cksum (aka Ksign) key
-	 */
-	hmac = crypto_alloc_shash(ctx->gk5e->cksum_name, 0, 0);
-	if (IS_ERR(hmac)) {
-		dprintk("%s: error %ld allocating hash '%s'\n",
-			__func__, PTR_ERR(hmac), ctx->gk5e->cksum_name);
-		err = PTR_ERR(hmac);
-		goto out_err;
-	}
-
-	err = crypto_shash_setkey(hmac, ctx->Ksess, ctx->gk5e->keylength);
-	if (err)
-		goto out_err_free_hmac;
-
-
-	desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(hmac), GFP_NOFS);
-	if (!desc) {
-		dprintk("%s: failed to allocate hash descriptor for '%s'\n",
-			__func__, ctx->gk5e->cksum_name);
-		err = -ENOMEM;
-		goto out_err_free_hmac;
-	}
-
-	desc->tfm = hmac;
-
-	err = crypto_shash_digest(desc, sigkeyconstant, slen, ctx->cksum);
-	kzfree(desc);
-	if (err)
-		goto out_err_free_hmac;
-	/*
-	 * allocate hash, and skciphers for data and seqnum encryption
-	 */
-	ctx->enc = crypto_alloc_sync_skcipher(ctx->gk5e->encrypt_name, 0, 0);
-	if (IS_ERR(ctx->enc)) {
-		err = PTR_ERR(ctx->enc);
-		goto out_err_free_hmac;
-	}
-
-	ctx->seq = crypto_alloc_sync_skcipher(ctx->gk5e->encrypt_name, 0, 0);
-	if (IS_ERR(ctx->seq)) {
-		crypto_free_sync_skcipher(ctx->enc);
-		err = PTR_ERR(ctx->seq);
-		goto out_err_free_hmac;
-	}
-
-	dprintk("RPC:       %s: returning success\n", __func__);
-
-	err = 0;
-
-out_err_free_hmac:
-	crypto_free_shash(hmac);
-out_err:
-	dprintk("RPC:       %s: returning %d\n", __func__, err);
-	return err;
-}
-
 static int
 context_derive_keys_new(struct krb5_ctx *ctx, gfp_t gfp_mask)
 {
@@ -649,8 +556,6 @@ gss_import_v2_context(const void *p, const void *end, struct krb5_ctx *ctx,
 	switch (ctx->enctype) {
 	case ENCTYPE_DES3_CBC_RAW:
 		return context_derive_keys_des3(ctx, gfp_mask);
-	case ENCTYPE_ARCFOUR_HMAC:
-		return context_derive_keys_rc4(ctx);
 	case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
 	case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
 		return context_derive_keys_new(ctx, gfp_mask);
diff --git a/net/sunrpc/auth_gss/gss_krb5_seal.c b/net/sunrpc/auth_gss/gss_krb5_seal.c
index f1d280accf43..33061417ec97 100644
--- a/net/sunrpc/auth_gss/gss_krb5_seal.c
+++ b/net/sunrpc/auth_gss/gss_krb5_seal.c
@@ -214,7 +214,6 @@ gss_get_mic_kerberos(struct gss_ctx *gss_ctx, struct xdr_buf *text,
 		BUG();
 	case ENCTYPE_DES_CBC_RAW:
 	case ENCTYPE_DES3_CBC_RAW:
-	case ENCTYPE_ARCFOUR_HMAC:
 		return gss_get_mic_v1(ctx, text, token);
 	case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
 	case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
diff --git a/net/sunrpc/auth_gss/gss_krb5_seqnum.c b/net/sunrpc/auth_gss/gss_krb5_seqnum.c
index 507105127095..fb117817ff5d 100644
--- a/net/sunrpc/auth_gss/gss_krb5_seqnum.c
+++ b/net/sunrpc/auth_gss/gss_krb5_seqnum.c
@@ -39,42 +39,6 @@
 # define RPCDBG_FACILITY        RPCDBG_AUTH
 #endif
 
-static s32
-krb5_make_rc4_seq_num(struct krb5_ctx *kctx, int direction, s32 seqnum,
-		      unsigned char *cksum, unsigned char *buf)
-{
-	struct crypto_sync_skcipher *cipher;
-	unsigned char *plain;
-	s32 code;
-
-	dprintk("RPC:       %s:\n", __func__);
-	cipher = crypto_alloc_sync_skcipher(kctx->gk5e->encrypt_name, 0, 0);
-	if (IS_ERR(cipher))
-		return PTR_ERR(cipher);
-
-	plain = kmalloc(8, GFP_NOFS);
-	if (!plain)
-		return -ENOMEM;
-
-	plain[0] = (unsigned char) ((seqnum >> 24) & 0xff);
-	plain[1] = (unsigned char) ((seqnum >> 16) & 0xff);
-	plain[2] = (unsigned char) ((seqnum >> 8) & 0xff);
-	plain[3] = (unsigned char) ((seqnum >> 0) & 0xff);
-	plain[4] = direction;
-	plain[5] = direction;
-	plain[6] = direction;
-	plain[7] = direction;
-
-	code = krb5_rc4_setup_seq_key(kctx, cipher, cksum);
-	if (code)
-		goto out;
-
-	code = krb5_encrypt(cipher, cksum, plain, buf, 8);
-out:
-	kfree(plain);
-	crypto_free_sync_skcipher(cipher);
-	return code;
-}
 s32
 krb5_make_seq_num(struct krb5_ctx *kctx,
 		struct crypto_sync_skcipher *key,
@@ -85,10 +49,6 @@ krb5_make_seq_num(struct krb5_ctx *kctx,
 	unsigned char *plain;
 	s32 code;
 
-	if (kctx->enctype == ENCTYPE_ARCFOUR_HMAC)
-		return krb5_make_rc4_seq_num(kctx, direction, seqnum,
-					     cksum, buf);
-
 	plain = kmalloc(8, GFP_NOFS);
 	if (!plain)
 		return -ENOMEM;
@@ -108,50 +68,6 @@ krb5_make_seq_num(struct krb5_ctx *kctx,
 	return code;
 }
 
-static s32
-krb5_get_rc4_seq_num(struct krb5_ctx *kctx, unsigned char *cksum,
-		     unsigned char *buf, int *direction, s32 *seqnum)
-{
-	struct crypto_sync_skcipher *cipher;
-	unsigned char *plain;
-	s32 code;
-
-	dprintk("RPC:       %s:\n", __func__);
-	cipher = crypto_alloc_sync_skcipher(kctx->gk5e->encrypt_name, 0, 0);
-	if (IS_ERR(cipher))
-		return PTR_ERR(cipher);
-
-	code = krb5_rc4_setup_seq_key(kctx, cipher, cksum);
-	if (code)
-		goto out;
-
-	plain = kmalloc(8, GFP_NOFS);
-	if (!plain) {
-		code = -ENOMEM;
-		goto out;
-	}
-
-	code = krb5_decrypt(cipher, cksum, buf, plain, 8);
-	if (code)
-		goto out_plain;
-
-	if ((plain[4] != plain[5]) || (plain[4] != plain[6])
-				   || (plain[4] != plain[7])) {
-		code = (s32)KG_BAD_SEQ;
-		goto out_plain;
-	}
-
-	*direction = plain[4];
-
-	*seqnum = ((plain[0] << 24) | (plain[1] << 16) |
-					(plain[2] << 8) | (plain[3]));
-out_plain:
-	kfree(plain);
-out:
-	crypto_free_sync_skcipher(cipher);
-	return code;
-}
-
 s32
 krb5_get_seq_num(struct krb5_ctx *kctx,
 	       unsigned char *cksum,
@@ -164,9 +80,6 @@ krb5_get_seq_num(struct krb5_ctx *kctx,
 
 	dprintk("RPC:       krb5_get_seq_num:\n");
 
-	if (kctx->enctype == ENCTYPE_ARCFOUR_HMAC)
-		return krb5_get_rc4_seq_num(kctx, cksum, buf,
-					    direction, seqnum);
 	plain = kmalloc(8, GFP_NOFS);
 	if (!plain)
 		return -ENOMEM;
diff --git a/net/sunrpc/auth_gss/gss_krb5_unseal.c b/net/sunrpc/auth_gss/gss_krb5_unseal.c
index aaab91cf24c8..ba04e3ec970a 100644
--- a/net/sunrpc/auth_gss/gss_krb5_unseal.c
+++ b/net/sunrpc/auth_gss/gss_krb5_unseal.c
@@ -218,7 +218,6 @@ gss_verify_mic_kerberos(struct gss_ctx *gss_ctx,
 		BUG();
 	case ENCTYPE_DES_CBC_RAW:
 	case ENCTYPE_DES3_CBC_RAW:
-	case ENCTYPE_ARCFOUR_HMAC:
 		return gss_verify_mic_v1(ctx, message_buffer, read_token);
 	case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
 	case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
diff --git a/net/sunrpc/auth_gss/gss_krb5_wrap.c b/net/sunrpc/auth_gss/gss_krb5_wrap.c
index cf0fd170ac18..a412a734ee17 100644
--- a/net/sunrpc/auth_gss/gss_krb5_wrap.c
+++ b/net/sunrpc/auth_gss/gss_krb5_wrap.c
@@ -236,26 +236,9 @@ gss_wrap_kerberos_v1(struct krb5_ctx *kctx, int offset,
 			       seq_send, ptr + GSS_KRB5_TOK_HDR_LEN, ptr + 8)))
 		return GSS_S_FAILURE;
 
-	if (kctx->enctype == ENCTYPE_ARCFOUR_HMAC) {
-		struct crypto_sync_skcipher *cipher;
-		int err;
-		cipher = crypto_alloc_sync_skcipher(kctx->gk5e->encrypt_name,
-						    0, 0);
-		if (IS_ERR(cipher))
-			return GSS_S_FAILURE;
-
-		krb5_rc4_setup_enc_key(kctx, cipher, seq_send);
-
-		err = gss_encrypt_xdr_buf(cipher, buf,
-					  offset + headlen - conflen, pages);
-		crypto_free_sync_skcipher(cipher);
-		if (err)
-			return GSS_S_FAILURE;
-	} else {
-		if (gss_encrypt_xdr_buf(kctx->enc, buf,
-					offset + headlen - conflen, pages))
-			return GSS_S_FAILURE;
-	}
+	if (gss_encrypt_xdr_buf(kctx->enc, buf,
+				offset + headlen - conflen, pages))
+		return GSS_S_FAILURE;
 
 	return (kctx->endtime < now) ? GSS_S_CONTEXT_EXPIRED : GSS_S_COMPLETE;
 }
@@ -316,37 +299,9 @@ gss_unwrap_kerberos_v1(struct krb5_ctx *kctx, int offset, int len,
 	crypt_offset = ptr + (GSS_KRB5_TOK_HDR_LEN + kctx->gk5e->cksumlength) -
 					(unsigned char *)buf->head[0].iov_base;
 
-	/*
-	 * Need plaintext seqnum to derive encryption key for arcfour-hmac
-	 */
-	if (krb5_get_seq_num(kctx, ptr + GSS_KRB5_TOK_HDR_LEN,
-			     ptr + 8, &direction, &seqnum))
-		return GSS_S_BAD_SIG;
-
-	if ((kctx->initiate && direction != 0xff) ||
-	    (!kctx->initiate && direction != 0))
-		return GSS_S_BAD_SIG;
-
 	buf->len = len;
-	if (kctx->enctype == ENCTYPE_ARCFOUR_HMAC) {
-		struct crypto_sync_skcipher *cipher;
-		int err;
-
-		cipher = crypto_alloc_sync_skcipher(kctx->gk5e->encrypt_name,
-						    0, 0);
-		if (IS_ERR(cipher))
-			return GSS_S_FAILURE;
-
-		krb5_rc4_setup_enc_key(kctx, cipher, seqnum);
-
-		err = gss_decrypt_xdr_buf(cipher, buf, crypt_offset);
-		crypto_free_sync_skcipher(cipher);
-		if (err)
-			return GSS_S_DEFECTIVE_TOKEN;
-	} else {
-		if (gss_decrypt_xdr_buf(kctx->enc, buf, crypt_offset))
-			return GSS_S_DEFECTIVE_TOKEN;
-	}
+	if (gss_decrypt_xdr_buf(kctx->enc, buf, crypt_offset))
+		return GSS_S_DEFECTIVE_TOKEN;
 
 	if (kctx->gk5e->keyed_cksum)
 		cksumkey = kctx->cksum;
@@ -370,6 +325,14 @@ gss_unwrap_kerberos_v1(struct krb5_ctx *kctx, int offset, int len,
 
 	/* do sequencing checks */
 
+	if (krb5_get_seq_num(kctx, ptr + GSS_KRB5_TOK_HDR_LEN,
+			     ptr + 8, &direction, &seqnum))
+		return GSS_S_BAD_SIG;
+
+	if ((kctx->initiate && direction != 0xff) ||
+	    (!kctx->initiate && direction != 0))
+		return GSS_S_BAD_SIG;
+
 	/* Copy the data back to the right position.  XXX: Would probably be
 	 * better to copy and encrypt at the same time. */
 
@@ -605,7 +568,6 @@ gss_wrap_kerberos(struct gss_ctx *gctx, int offset,
 		BUG();
 	case ENCTYPE_DES_CBC_RAW:
 	case ENCTYPE_DES3_CBC_RAW:
-	case ENCTYPE_ARCFOUR_HMAC:
 		return gss_wrap_kerberos_v1(kctx, offset, buf, pages);
 	case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
 	case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
@@ -624,7 +586,6 @@ gss_unwrap_kerberos(struct gss_ctx *gctx, int offset,
 		BUG();
 	case ENCTYPE_DES_CBC_RAW:
 	case ENCTYPE_DES3_CBC_RAW:
-	case ENCTYPE_ARCFOUR_HMAC:
 		return gss_unwrap_kerberos_v1(kctx, offset, len, buf,
 					      &gctx->slack, &gctx->align);
 	case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
-- 
2.17.1


^ permalink raw reply related	[flat|nested] 17+ messages in thread

* [RFC PATCH 4/7] crypto: remove ARC4 support from the skcipher API
  2020-07-02 10:19 [RFC PATCH 0/7] crypto: get rid of ecb(arc4) Ard Biesheuvel
                   ` (2 preceding siblings ...)
  2020-07-02 10:19 ` [RFC PATCH 3/7] SUNRPC: remove RC4-HMAC-MD5 support from KerberosV Ard Biesheuvel
@ 2020-07-02 10:19 ` Ard Biesheuvel
  2020-07-02 17:50   ` Eric Biggers
  2020-07-02 10:19 ` [RFC PATCH 5/7] crypto: n2 - remove ecb(arc4) support Ard Biesheuvel
                   ` (2 subsequent siblings)
  6 siblings, 1 reply; 17+ messages in thread
From: Ard Biesheuvel @ 2020-07-02 10:19 UTC (permalink / raw)
  To: linux-kernel
  Cc: Ard Biesheuvel, Herbert Xu, David S. Miller, Greg Kroah-Hartman,
	Trond Myklebust, Anna Schumaker, J. Bruce Fields, Chuck Lever,
	Eric Biggers, linux-crypto, netdev, devel, linux-nfs

Remove the generic ecb(arc4) skcipher, which is slightly cumbersome from
a maintenance perspective, since it does not quite behave like other
skciphers do in terms of key vs IV lifetime. Since we are leaving the
library interface in place, which is used by the various WEP and TKIP
implementations we have in the tree, we can safely drop this code now
it no longer has any users.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 crypto/Kconfig                               | 12 ----
 crypto/Makefile                              |  1 -
 crypto/arc4.c                                | 76 --------------------
 drivers/net/wireless/intel/ipw2x00/Kconfig   |  1 -
 drivers/net/wireless/intersil/hostap/Kconfig |  1 -
 5 files changed, 91 deletions(-)

diff --git a/crypto/Kconfig b/crypto/Kconfig
index 091c0a0bbf26..fd0d1f78ac47 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -1197,18 +1197,6 @@ config CRYPTO_ANUBIS
 	  <https://www.cosic.esat.kuleuven.be/nessie/reports/>
 	  <http://www.larc.usp.br/~pbarreto/AnubisPage.html>
 
-config CRYPTO_ARC4
-	tristate "ARC4 cipher algorithm"
-	select CRYPTO_SKCIPHER
-	select CRYPTO_LIB_ARC4
-	help
-	  ARC4 cipher algorithm.
-
-	  ARC4 is a stream cipher using keys ranging from 8 bits to 2048
-	  bits in length.  This algorithm is required for driver-based
-	  WEP, but it should not be for other purposes because of the
-	  weakness of the algorithm.
-
 config CRYPTO_BLOWFISH
 	tristate "Blowfish cipher algorithm"
 	select CRYPTO_ALGAPI
diff --git a/crypto/Makefile b/crypto/Makefile
index 4ca12b6044f7..af88c7e30b3c 100644
--- a/crypto/Makefile
+++ b/crypto/Makefile
@@ -128,7 +128,6 @@ obj-$(CONFIG_CRYPTO_CAMELLIA) += camellia_generic.o
 obj-$(CONFIG_CRYPTO_CAST_COMMON) += cast_common.o
 obj-$(CONFIG_CRYPTO_CAST5) += cast5_generic.o
 obj-$(CONFIG_CRYPTO_CAST6) += cast6_generic.o
-obj-$(CONFIG_CRYPTO_ARC4) += arc4.o
 obj-$(CONFIG_CRYPTO_TEA) += tea.o
 obj-$(CONFIG_CRYPTO_KHAZAD) += khazad.o
 obj-$(CONFIG_CRYPTO_ANUBIS) += anubis.o
diff --git a/crypto/arc4.c b/crypto/arc4.c
deleted file mode 100644
index aa79571dbd49..000000000000
--- a/crypto/arc4.c
+++ /dev/null
@@ -1,76 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * Cryptographic API
- *
- * ARC4 Cipher Algorithm
- *
- * Jon Oberheide <jon@oberheide.org>
- */
-
-#include <crypto/algapi.h>
-#include <crypto/arc4.h>
-#include <crypto/internal/skcipher.h>
-#include <linux/init.h>
-#include <linux/module.h>
-
-static int crypto_arc4_setkey(struct crypto_skcipher *tfm, const u8 *in_key,
-			      unsigned int key_len)
-{
-	struct arc4_ctx *ctx = crypto_skcipher_ctx(tfm);
-
-	return arc4_setkey(ctx, in_key, key_len);
-}
-
-static int crypto_arc4_crypt(struct skcipher_request *req)
-{
-	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
-	struct arc4_ctx *ctx = crypto_skcipher_ctx(tfm);
-	struct skcipher_walk walk;
-	int err;
-
-	err = skcipher_walk_virt(&walk, req, false);
-
-	while (walk.nbytes > 0) {
-		arc4_crypt(ctx, walk.dst.virt.addr, walk.src.virt.addr,
-			   walk.nbytes);
-		err = skcipher_walk_done(&walk, 0);
-	}
-
-	return err;
-}
-
-static struct skcipher_alg arc4_alg = {
-	/*
-	 * For legacy reasons, this is named "ecb(arc4)", not "arc4".
-	 * Nevertheless it's actually a stream cipher, not a block cipher.
-	 */
-	.base.cra_name		=	"ecb(arc4)",
-	.base.cra_driver_name	=	"ecb(arc4)-generic",
-	.base.cra_priority	=	100,
-	.base.cra_blocksize	=	ARC4_BLOCK_SIZE,
-	.base.cra_ctxsize	=	sizeof(struct arc4_ctx),
-	.base.cra_module	=	THIS_MODULE,
-	.min_keysize		=	ARC4_MIN_KEY_SIZE,
-	.max_keysize		=	ARC4_MAX_KEY_SIZE,
-	.setkey			=	crypto_arc4_setkey,
-	.encrypt		=	crypto_arc4_crypt,
-	.decrypt		=	crypto_arc4_crypt,
-};
-
-static int __init arc4_init(void)
-{
-	return crypto_register_skcipher(&arc4_alg);
-}
-
-static void __exit arc4_exit(void)
-{
-	crypto_unregister_skcipher(&arc4_alg);
-}
-
-subsys_initcall(arc4_init);
-module_exit(arc4_exit);
-
-MODULE_LICENSE("GPL");
-MODULE_DESCRIPTION("ARC4 Cipher Algorithm");
-MODULE_AUTHOR("Jon Oberheide <jon@oberheide.org>");
-MODULE_ALIAS_CRYPTO("ecb(arc4)");
diff --git a/drivers/net/wireless/intel/ipw2x00/Kconfig b/drivers/net/wireless/intel/ipw2x00/Kconfig
index d00386915a9d..82b7eea3495f 100644
--- a/drivers/net/wireless/intel/ipw2x00/Kconfig
+++ b/drivers/net/wireless/intel/ipw2x00/Kconfig
@@ -160,7 +160,6 @@ config LIBIPW
 	select WIRELESS_EXT
 	select WEXT_SPY
 	select CRYPTO
-	select CRYPTO_ARC4
 	select CRYPTO_ECB
 	select CRYPTO_AES
 	select CRYPTO_MICHAEL_MIC
diff --git a/drivers/net/wireless/intersil/hostap/Kconfig b/drivers/net/wireless/intersil/hostap/Kconfig
index 6ad88299432f..428fb6f55f51 100644
--- a/drivers/net/wireless/intersil/hostap/Kconfig
+++ b/drivers/net/wireless/intersil/hostap/Kconfig
@@ -5,7 +5,6 @@ config HOSTAP
 	select WEXT_SPY
 	select WEXT_PRIV
 	select CRYPTO
-	select CRYPTO_ARC4
 	select CRYPTO_ECB
 	select CRYPTO_AES
 	select CRYPTO_MICHAEL_MIC
-- 
2.17.1


^ permalink raw reply related	[flat|nested] 17+ messages in thread

* [RFC PATCH 5/7] crypto: n2 - remove ecb(arc4) support
  2020-07-02 10:19 [RFC PATCH 0/7] crypto: get rid of ecb(arc4) Ard Biesheuvel
                   ` (3 preceding siblings ...)
  2020-07-02 10:19 ` [RFC PATCH 4/7] crypto: remove ARC4 support from the skcipher API Ard Biesheuvel
@ 2020-07-02 10:19 ` Ard Biesheuvel
  2020-07-02 10:19 ` [RFC PATCH 6/7] crypto: bcm-iproc " Ard Biesheuvel
  2020-07-02 10:19 ` [RFC PATCH 7/7] crypto: tcrypt - remove ecb(arc4) testing/benchmarking support Ard Biesheuvel
  6 siblings, 0 replies; 17+ messages in thread
From: Ard Biesheuvel @ 2020-07-02 10:19 UTC (permalink / raw)
  To: linux-kernel
  Cc: Ard Biesheuvel, Herbert Xu, David S. Miller, Greg Kroah-Hartman,
	Trond Myklebust, Anna Schumaker, J. Bruce Fields, Chuck Lever,
	Eric Biggers, linux-crypto, netdev, devel, linux-nfs

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 drivers/crypto/n2_core.c | 46 --------------------
 1 file changed, 46 deletions(-)

diff --git a/drivers/crypto/n2_core.c b/drivers/crypto/n2_core.c
index 6a828bbecea4..c347e58cd9a1 100644
--- a/drivers/crypto/n2_core.c
+++ b/drivers/crypto/n2_core.c
@@ -662,7 +662,6 @@ struct n2_skcipher_context {
 		u8		aes[AES_MAX_KEY_SIZE];
 		u8		des[DES_KEY_SIZE];
 		u8		des3[3 * DES_KEY_SIZE];
-		u8		arc4[258]; /* S-box, X, Y */
 	} key;
 };
 
@@ -789,36 +788,6 @@ static int n2_3des_setkey(struct crypto_skcipher *skcipher, const u8 *key,
 	return 0;
 }
 
-static int n2_arc4_setkey(struct crypto_skcipher *skcipher, const u8 *key,
-			  unsigned int keylen)
-{
-	struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
-	struct n2_skcipher_context *ctx = crypto_tfm_ctx(tfm);
-	struct n2_skcipher_alg *n2alg = n2_skcipher_alg(skcipher);
-	u8 *s = ctx->key.arc4;
-	u8 *x = s + 256;
-	u8 *y = x + 1;
-	int i, j, k;
-
-	ctx->enc_type = n2alg->enc_type;
-
-	j = k = 0;
-	*x = 0;
-	*y = 0;
-	for (i = 0; i < 256; i++)
-		s[i] = i;
-	for (i = 0; i < 256; i++) {
-		u8 a = s[i];
-		j = (j + key[k] + a) & 0xff;
-		s[i] = s[j];
-		s[j] = a;
-		if (++k >= keylen)
-			k = 0;
-	}
-
-	return 0;
-}
-
 static inline int skcipher_descriptor_len(int nbytes, unsigned int block_size)
 {
 	int this_len = nbytes;
@@ -1122,21 +1091,6 @@ struct n2_skcipher_tmpl {
 };
 
 static const struct n2_skcipher_tmpl skcipher_tmpls[] = {
-	/* ARC4: only ECB is supported (chaining bits ignored) */
-	{	.name		= "ecb(arc4)",
-		.drv_name	= "ecb-arc4",
-		.block_size	= 1,
-		.enc_type	= (ENC_TYPE_ALG_RC4_STREAM |
-				   ENC_TYPE_CHAINING_ECB),
-		.skcipher	= {
-			.min_keysize	= 1,
-			.max_keysize	= 256,
-			.setkey		= n2_arc4_setkey,
-			.encrypt	= n2_encrypt_ecb,
-			.decrypt	= n2_decrypt_ecb,
-		},
-	},
-
 	/* DES: ECB CBC and CFB are supported */
 	{	.name		= "ecb(des)",
 		.drv_name	= "ecb-des",
-- 
2.17.1


^ permalink raw reply related	[flat|nested] 17+ messages in thread

* [RFC PATCH 6/7] crypto: bcm-iproc - remove ecb(arc4) support
  2020-07-02 10:19 [RFC PATCH 0/7] crypto: get rid of ecb(arc4) Ard Biesheuvel
                   ` (4 preceding siblings ...)
  2020-07-02 10:19 ` [RFC PATCH 5/7] crypto: n2 - remove ecb(arc4) support Ard Biesheuvel
@ 2020-07-02 10:19 ` Ard Biesheuvel
  2020-07-02 10:19 ` [RFC PATCH 7/7] crypto: tcrypt - remove ecb(arc4) testing/benchmarking support Ard Biesheuvel
  6 siblings, 0 replies; 17+ messages in thread
From: Ard Biesheuvel @ 2020-07-02 10:19 UTC (permalink / raw)
  To: linux-kernel
  Cc: Ard Biesheuvel, Herbert Xu, David S. Miller, Greg Kroah-Hartman,
	Trond Myklebust, Anna Schumaker, J. Bruce Fields, Chuck Lever,
	Eric Biggers, linux-crypto, netdev, devel, linux-nfs

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 drivers/crypto/bcm/cipher.c | 96 +-------------------
 drivers/crypto/bcm/cipher.h |  1 -
 drivers/crypto/bcm/spu.c    | 23 +----
 drivers/crypto/bcm/spu.h    |  1 -
 drivers/crypto/bcm/spu2.c   | 12 +--
 drivers/crypto/bcm/spu2.h   |  1 -
 6 files changed, 6 insertions(+), 128 deletions(-)

diff --git a/drivers/crypto/bcm/cipher.c b/drivers/crypto/bcm/cipher.c
index a353217a0d33..f73b4bd86482 100644
--- a/drivers/crypto/bcm/cipher.c
+++ b/drivers/crypto/bcm/cipher.c
@@ -165,10 +165,6 @@ spu_skcipher_rx_sg_create(struct brcm_message *mssg,
 		return -EFAULT;
 	}
 
-	if (ctx->cipher.alg == CIPHER_ALG_RC4)
-		/* Add buffer to catch 260-byte SUPDT field for RC4 */
-		sg_set_buf(sg++, rctx->msg_buf.c.supdt_tweak, SPU_SUPDT_LEN);
-
 	if (stat_pad_len)
 		sg_set_buf(sg++, rctx->msg_buf.rx_stat_pad, stat_pad_len);
 
@@ -317,7 +313,6 @@ static int handle_skcipher_req(struct iproc_reqctx_s *rctx)
 	u8 local_iv_ctr[MAX_IV_SIZE];
 	u32 stat_pad_len;	/* num bytes to align status field */
 	u32 pad_len;		/* total length of all padding */
-	bool update_key = false;
 	struct brcm_message *mssg;	/* mailbox message */
 
 	/* number of entries in src and dst sg in mailbox message. */
@@ -391,28 +386,6 @@ static int handle_skcipher_req(struct iproc_reqctx_s *rctx)
 		}
 	}
 
-	if (ctx->cipher.alg == CIPHER_ALG_RC4) {
-		rx_frag_num++;
-		if (chunk_start) {
-			/*
-			 * for non-first RC4 chunks, use SUPDT from previous
-			 * response as key for this chunk.
-			 */
-			cipher_parms.key_buf = rctx->msg_buf.c.supdt_tweak;
-			update_key = true;
-			cipher_parms.type = CIPHER_TYPE_UPDT;
-		} else if (!rctx->is_encrypt) {
-			/*
-			 * First RC4 chunk. For decrypt, key in pre-built msg
-			 * header may have been changed if encrypt required
-			 * multiple chunks. So revert the key to the
-			 * ctx->enckey value.
-			 */
-			update_key = true;
-			cipher_parms.type = CIPHER_TYPE_INIT;
-		}
-	}
-
 	if (ctx->max_payload == SPU_MAX_PAYLOAD_INF)
 		flow_log("max_payload infinite\n");
 	else
@@ -425,14 +398,9 @@ static int handle_skcipher_req(struct iproc_reqctx_s *rctx)
 	memcpy(rctx->msg_buf.bcm_spu_req_hdr, ctx->bcm_spu_req_hdr,
 	       sizeof(rctx->msg_buf.bcm_spu_req_hdr));
 
-	/*
-	 * Pass SUPDT field as key. Key field in finish() call is only used
-	 * when update_key has been set above for RC4. Will be ignored in
-	 * all other cases.
-	 */
 	spu->spu_cipher_req_finish(rctx->msg_buf.bcm_spu_req_hdr + BCM_HDR_LEN,
 				   ctx->spu_req_hdr_len, !(rctx->is_encrypt),
-				   &cipher_parms, update_key, chunksize);
+				   &cipher_parms, chunksize);
 
 	atomic64_add(chunksize, &iproc_priv.bytes_out);
 
@@ -527,9 +495,6 @@ static void handle_skcipher_resp(struct iproc_reqctx_s *rctx)
 		 __func__, rctx->total_received, payload_len);
 
 	dump_sg(req->dst, rctx->total_received, payload_len);
-	if (ctx->cipher.alg == CIPHER_ALG_RC4)
-		packet_dump("  supdt ", rctx->msg_buf.c.supdt_tweak,
-			    SPU_SUPDT_LEN);
 
 	rctx->total_received += payload_len;
 	if (rctx->total_received == rctx->total_todo) {
@@ -1853,26 +1818,6 @@ static int aes_setkey(struct crypto_skcipher *cipher, const u8 *key,
 	return 0;
 }
 
-static int rc4_setkey(struct crypto_skcipher *cipher, const u8 *key,
-		      unsigned int keylen)
-{
-	struct iproc_ctx_s *ctx = crypto_skcipher_ctx(cipher);
-	int i;
-
-	ctx->enckeylen = ARC4_MAX_KEY_SIZE + ARC4_STATE_SIZE;
-
-	ctx->enckey[0] = 0x00;	/* 0x00 */
-	ctx->enckey[1] = 0x00;	/* i    */
-	ctx->enckey[2] = 0x00;	/* 0x00 */
-	ctx->enckey[3] = 0x00;	/* j    */
-	for (i = 0; i < ARC4_MAX_KEY_SIZE; i++)
-		ctx->enckey[i + ARC4_STATE_SIZE] = key[i % keylen];
-
-	ctx->cipher_type = CIPHER_TYPE_INIT;
-
-	return 0;
-}
-
 static int skcipher_setkey(struct crypto_skcipher *cipher, const u8 *key,
 			     unsigned int keylen)
 {
@@ -1895,9 +1840,6 @@ static int skcipher_setkey(struct crypto_skcipher *cipher, const u8 *key,
 	case CIPHER_ALG_AES:
 		err = aes_setkey(cipher, key, keylen);
 		break;
-	case CIPHER_ALG_RC4:
-		err = rc4_setkey(cipher, key, keylen);
-		break;
 	default:
 		pr_err("%s() Error: unknown cipher alg\n", __func__);
 		err = -EINVAL;
@@ -1905,11 +1847,9 @@ static int skcipher_setkey(struct crypto_skcipher *cipher, const u8 *key,
 	if (err)
 		return err;
 
-	/* RC4 already populated ctx->enkey */
-	if (ctx->cipher.alg != CIPHER_ALG_RC4) {
-		memcpy(ctx->enckey, key, keylen);
-		ctx->enckeylen = keylen;
-	}
+	memcpy(ctx->enckey, key, keylen);
+	ctx->enckeylen = keylen;
+
 	/* SPU needs XTS keys in the reverse order the crypto API presents */
 	if ((ctx->cipher.alg == CIPHER_ALG_AES) &&
 	    (ctx->cipher.mode == CIPHER_MODE_XTS)) {
@@ -2872,9 +2812,6 @@ static int aead_authenc_setkey(struct crypto_aead *cipher,
 			goto badkey;
 		}
 		break;
-	case CIPHER_ALG_RC4:
-		ctx->cipher_type = CIPHER_TYPE_INIT;
-		break;
 	default:
 		pr_err("%s() Error: Unknown cipher alg\n", __func__);
 		return -EINVAL;
@@ -3573,25 +3510,6 @@ static struct iproc_alg_s driver_algs[] = {
 	 },
 
 /* SKCIPHER algorithms. */
-	{
-	 .type = CRYPTO_ALG_TYPE_SKCIPHER,
-	 .alg.skcipher = {
-			.base.cra_name = "ecb(arc4)",
-			.base.cra_driver_name = "ecb-arc4-iproc",
-			.base.cra_blocksize = ARC4_BLOCK_SIZE,
-			.min_keysize = ARC4_MIN_KEY_SIZE,
-			.max_keysize = ARC4_MAX_KEY_SIZE,
-			.ivsize = 0,
-			},
-	 .cipher_info = {
-			 .alg = CIPHER_ALG_RC4,
-			 .mode = CIPHER_MODE_NONE,
-			 },
-	 .auth_info = {
-		       .alg = HASH_ALG_NONE,
-		       .mode = HASH_MODE_NONE,
-		       },
-	 },
 	{
 	 .type = CRYPTO_ALG_TYPE_SKCIPHER,
 	 .alg.skcipher = {
@@ -4495,15 +4413,9 @@ static void spu_counters_init(void)
 
 static int spu_register_skcipher(struct iproc_alg_s *driver_alg)
 {
-	struct spu_hw *spu = &iproc_priv.spu;
 	struct skcipher_alg *crypto = &driver_alg->alg.skcipher;
 	int err;
 
-	/* SPU2 does not support RC4 */
-	if ((driver_alg->cipher_info.alg == CIPHER_ALG_RC4) &&
-	    (spu->spu_type == SPU_TYPE_SPU2))
-		return 0;
-
 	crypto->base.cra_module = THIS_MODULE;
 	crypto->base.cra_priority = cipher_pri;
 	crypto->base.cra_alignmask = 0;
diff --git a/drivers/crypto/bcm/cipher.h b/drivers/crypto/bcm/cipher.h
index b6d83e3aa46c..035c8389cb3d 100644
--- a/drivers/crypto/bcm/cipher.h
+++ b/drivers/crypto/bcm/cipher.h
@@ -388,7 +388,6 @@ struct spu_hw {
 				      u16 spu_req_hdr_len,
 				      unsigned int is_inbound,
 				      struct spu_cipher_parms *cipher_parms,
-				      bool update_key,
 				      unsigned int data_size);
 	void (*spu_request_pad)(u8 *pad_start, u32 gcm_padding,
 				u32 hash_pad_len, enum hash_alg auth_alg,
diff --git a/drivers/crypto/bcm/spu.c b/drivers/crypto/bcm/spu.c
index e7562e9bf396..fe126f95c702 100644
--- a/drivers/crypto/bcm/spu.c
+++ b/drivers/crypto/bcm/spu.c
@@ -222,10 +222,6 @@ void spum_dump_msg_hdr(u8 *buf, unsigned int buf_len)
 				cipher_key_len = 24;
 				name = "3DES";
 				break;
-			case CIPHER_ALG_RC4:
-				cipher_key_len = 260;
-				name = "ARC4";
-				break;
 			case CIPHER_ALG_AES:
 				switch (cipher_type) {
 				case CIPHER_TYPE_AES128:
@@ -919,21 +915,16 @@ u16 spum_cipher_req_init(u8 *spu_hdr, struct spu_cipher_parms *cipher_parms)
  * @spu_req_hdr_len: Length in bytes of the SPU request header
  * @isInbound:       0 encrypt, 1 decrypt
  * @cipher_parms:    Parameters describing cipher operation to be performed
- * @update_key:      If true, rewrite the cipher key in SCTX
  * @data_size:       Length of the data in the BD field
  *
  * Assumes much of the header was already filled in at setkey() time in
  * spum_cipher_req_init().
- * spum_cipher_req_init() fills in the encryption key. For RC4, when submitting
- * a request for a non-first chunk, we use the 260-byte SUPDT field from the
- * previous response as the key. update_key is true for this case. Unused in all
- * other cases.
+ * spum_cipher_req_init() fills in the encryption key.
  */
 void spum_cipher_req_finish(u8 *spu_hdr,
 			    u16 spu_req_hdr_len,
 			    unsigned int is_inbound,
 			    struct spu_cipher_parms *cipher_parms,
-			    bool update_key,
 			    unsigned int data_size)
 {
 	struct SPUHEADER *spuh;
@@ -948,11 +939,6 @@ void spum_cipher_req_finish(u8 *spu_hdr,
 	flow_log(" in: %u\n", is_inbound);
 	flow_log(" cipher alg: %u, cipher_type: %u\n", cipher_parms->alg,
 		 cipher_parms->type);
-	if (update_key) {
-		flow_log(" cipher key len: %u\n", cipher_parms->key_len);
-		flow_dump("  key: ", cipher_parms->key_buf,
-			  cipher_parms->key_len);
-	}
 
 	/*
 	 * In XTS mode, API puts "i" parameter (block tweak) in IV.  For
@@ -981,13 +967,6 @@ void spum_cipher_req_finish(u8 *spu_hdr,
 	else
 		cipher_bits &= ~CIPHER_INBOUND;
 
-	/* update encryption key for RC4 on non-first chunk */
-	if (update_key) {
-		spuh->sa.cipher_flags |=
-			cipher_parms->type << CIPHER_TYPE_SHIFT;
-		memcpy(spuh + 1, cipher_parms->key_buf, cipher_parms->key_len);
-	}
-
 	if (cipher_parms->alg && cipher_parms->iv_buf && cipher_parms->iv_len)
 		/* cipher iv provided so put it in here */
 		memcpy(bdesc_ptr - cipher_parms->iv_len, cipher_parms->iv_buf,
diff --git a/drivers/crypto/bcm/spu.h b/drivers/crypto/bcm/spu.h
index b247bc5b9354..dd132389bcaa 100644
--- a/drivers/crypto/bcm/spu.h
+++ b/drivers/crypto/bcm/spu.h
@@ -251,7 +251,6 @@ void spum_cipher_req_finish(u8 *spu_hdr,
 			    u16 spu_req_hdr_len,
 			    unsigned int is_inbound,
 			    struct spu_cipher_parms *cipher_parms,
-			    bool update_key,
 			    unsigned int data_size);
 
 void spum_request_pad(u8 *pad_start,
diff --git a/drivers/crypto/bcm/spu2.c b/drivers/crypto/bcm/spu2.c
index 59abb5ecefa4..c860ffb0b4c3 100644
--- a/drivers/crypto/bcm/spu2.c
+++ b/drivers/crypto/bcm/spu2.c
@@ -1170,21 +1170,16 @@ u16 spu2_cipher_req_init(u8 *spu_hdr, struct spu_cipher_parms *cipher_parms)
  * @spu_req_hdr_len: Length in bytes of the SPU request header
  * @isInbound:       0 encrypt, 1 decrypt
  * @cipher_parms:    Parameters describing cipher operation to be performed
- * @update_key:      If true, rewrite the cipher key in SCTX
  * @data_size:       Length of the data in the BD field
  *
  * Assumes much of the header was already filled in at setkey() time in
  * spu_cipher_req_init().
- * spu_cipher_req_init() fills in the encryption key. For RC4, when submitting a
- * request for a non-first chunk, we use the 260-byte SUPDT field from the
- * previous response as the key. update_key is true for this case. Unused in all
- * other cases.
+ * spu_cipher_req_init() fills in the encryption key.
  */
 void spu2_cipher_req_finish(u8 *spu_hdr,
 			    u16 spu_req_hdr_len,
 			    unsigned int is_inbound,
 			    struct spu_cipher_parms *cipher_parms,
-			    bool update_key,
 			    unsigned int data_size)
 {
 	struct SPU2_FMD *fmd;
@@ -1196,11 +1191,6 @@ void spu2_cipher_req_finish(u8 *spu_hdr,
 	flow_log(" in: %u\n", is_inbound);
 	flow_log(" cipher alg: %u, cipher_type: %u\n", cipher_parms->alg,
 		 cipher_parms->type);
-	if (update_key) {
-		flow_log(" cipher key len: %u\n", cipher_parms->key_len);
-		flow_dump("  key: ", cipher_parms->key_buf,
-			  cipher_parms->key_len);
-	}
 	flow_log(" iv len: %d\n", cipher_parms->iv_len);
 	flow_dump("    iv: ", cipher_parms->iv_buf, cipher_parms->iv_len);
 	flow_log(" data_size: %u\n", data_size);
diff --git a/drivers/crypto/bcm/spu2.h b/drivers/crypto/bcm/spu2.h
index 03af6c38df7f..6e666bfb3cfc 100644
--- a/drivers/crypto/bcm/spu2.h
+++ b/drivers/crypto/bcm/spu2.h
@@ -200,7 +200,6 @@ void spu2_cipher_req_finish(u8 *spu_hdr,
 			    u16 spu_req_hdr_len,
 			    unsigned int is_inbound,
 			    struct spu_cipher_parms *cipher_parms,
-			    bool update_key,
 			    unsigned int data_size);
 void spu2_request_pad(u8 *pad_start, u32 gcm_padding, u32 hash_pad_len,
 		      enum hash_alg auth_alg, enum hash_mode auth_mode,
-- 
2.17.1


^ permalink raw reply related	[flat|nested] 17+ messages in thread

* [RFC PATCH 7/7] crypto: tcrypt - remove ecb(arc4) testing/benchmarking support
  2020-07-02 10:19 [RFC PATCH 0/7] crypto: get rid of ecb(arc4) Ard Biesheuvel
                   ` (5 preceding siblings ...)
  2020-07-02 10:19 ` [RFC PATCH 6/7] crypto: bcm-iproc " Ard Biesheuvel
@ 2020-07-02 10:19 ` Ard Biesheuvel
  6 siblings, 0 replies; 17+ messages in thread
From: Ard Biesheuvel @ 2020-07-02 10:19 UTC (permalink / raw)
  To: linux-kernel
  Cc: Ard Biesheuvel, Herbert Xu, David S. Miller, Greg Kroah-Hartman,
	Trond Myklebust, Anna Schumaker, J. Bruce Fields, Chuck Lever,
	Eric Biggers, linux-crypto, netdev, devel, linux-nfs

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 crypto/tcrypt.c  | 21 +------
 crypto/testmgr.c |  7 ---
 crypto/testmgr.h | 62 --------------------
 3 files changed, 1 insertion(+), 89 deletions(-)

diff --git a/crypto/tcrypt.c b/crypto/tcrypt.c
index ba0b7702f2e9..72828c4acd3a 100644
--- a/crypto/tcrypt.c
+++ b/crypto/tcrypt.c
@@ -68,7 +68,7 @@ static char *tvmem[TVMEMSIZE];
 static const char *check[] = {
 	"des", "md5", "des3_ede", "rot13", "sha1", "sha224", "sha256", "sm3",
 	"blowfish", "twofish", "serpent", "sha384", "sha512", "md4", "aes",
-	"cast6", "arc4", "michael_mic", "deflate", "crc32c", "tea", "xtea",
+	"cast6", "michael_mic", "deflate", "crc32c", "tea", "xtea",
 	"khazad", "wp512", "wp384", "wp256", "tnepres", "xeta",  "fcrypt",
 	"camellia", "seed", "salsa20", "rmd128", "rmd160", "rmd256", "rmd320",
 	"lzo", "lzo-rle", "cts", "sha3-224", "sha3-256", "sha3-384",
@@ -1762,10 +1762,6 @@ static int do_test(const char *alg, u32 type, u32 mask, int m, u32 num_mb)
 		ret += tcrypt_test("xts(cast6)");
 		break;
 
-	case 16:
-		ret += tcrypt_test("ecb(arc4)");
-		break;
-
 	case 17:
 		ret += tcrypt_test("michael_mic");
 		break;
@@ -2201,11 +2197,6 @@ static int do_test(const char *alg, u32 type, u32 mask, int m, u32 num_mb)
 				  speed_template_32_64);
 		break;
 
-	case 208:
-		test_cipher_speed("ecb(arc4)", ENCRYPT, sec, NULL, 0,
-				  speed_template_8);
-		break;
-
 	case 209:
 		test_cipher_speed("ecb(cast5)", ENCRYPT, sec, NULL, 0,
 				  speed_template_8_16);
@@ -2720,11 +2711,6 @@ static int do_test(const char *alg, u32 type, u32 mask, int m, u32 num_mb)
 				   speed_template_32_48_64);
 		break;
 
-	case 505:
-		test_acipher_speed("ecb(arc4)", ENCRYPT, sec, NULL, 0,
-				   speed_template_8);
-		break;
-
 	case 506:
 		test_acipher_speed("ecb(cast5)", ENCRYPT, sec, NULL, 0,
 				   speed_template_8_16);
@@ -2932,11 +2918,6 @@ static int do_test(const char *alg, u32 type, u32 mask, int m, u32 num_mb)
 				       speed_template_32_48_64, num_mb);
 		break;
 
-	case 605:
-		test_mb_skcipher_speed("ecb(arc4)", ENCRYPT, sec, NULL, 0,
-				       speed_template_8, num_mb);
-		break;
-
 	case 606:
 		test_mb_skcipher_speed("ecb(cast5)", ENCRYPT, sec, NULL, 0,
 				       speed_template_8_16, num_mb);
diff --git a/crypto/testmgr.c b/crypto/testmgr.c
index 6863f911fcee..7c1bdc5690e2 100644
--- a/crypto/testmgr.c
+++ b/crypto/testmgr.c
@@ -4783,13 +4783,6 @@ static const struct alg_test_desc alg_test_descs[] = {
 		.suite = {
 			.cipher = __VECS(anubis_tv_template)
 		}
-	}, {
-		.alg = "ecb(arc4)",
-		.generic_driver = "ecb(arc4)-generic",
-		.test = alg_test_skcipher,
-		.suite = {
-			.cipher = __VECS(arc4_tv_template)
-		}
 	}, {
 		.alg = "ecb(blowfish)",
 		.test = alg_test_skcipher,
diff --git a/crypto/testmgr.h b/crypto/testmgr.h
index d29983908c38..48cd6330ec8d 100644
--- a/crypto/testmgr.h
+++ b/crypto/testmgr.h
@@ -22490,68 +22490,6 @@ static const struct cipher_testvec cast5_ctr_tv_template[] = {
 	},
 };
 
-/*
- * ARC4 test vectors from OpenSSL
- */
-static const struct cipher_testvec arc4_tv_template[] = {
-	{
-		.key	= "\x01\x23\x45\x67\x89\xab\xcd\xef",
-		.klen	= 8,
-		.ptext	= "\x01\x23\x45\x67\x89\xab\xcd\xef",
-		.ctext	= "\x75\xb7\x87\x80\x99\xe0\xc5\x96",
-		.len	= 8,
-	}, {
-		.key	= "\x01\x23\x45\x67\x89\xab\xcd\xef",
-		.klen	= 8,
-		.ptext	= "\x00\x00\x00\x00\x00\x00\x00\x00",
-		.ctext	= "\x74\x94\xc2\xe7\x10\x4b\x08\x79",
-		.len	= 8,
-	}, {
-		.key	= "\x00\x00\x00\x00\x00\x00\x00\x00",
-		.klen	= 8,
-		.ptext	= "\x00\x00\x00\x00\x00\x00\x00\x00",
-		.ctext	= "\xde\x18\x89\x41\xa3\x37\x5d\x3a",
-		.len	= 8,
-	}, {
-		.key	= "\xef\x01\x23\x45",
-		.klen	= 4,
-		.ptext	= "\x00\x00\x00\x00\x00\x00\x00\x00"
-			  "\x00\x00\x00\x00\x00\x00\x00\x00"
-			  "\x00\x00\x00\x00",
-		.ctext	= "\xd6\xa1\x41\xa7\xec\x3c\x38\xdf"
-			  "\xbd\x61\x5a\x11\x62\xe1\xc7\xba"
-			  "\x36\xb6\x78\x58",
-		.len	= 20,
-	}, {
-		.key	= "\x01\x23\x45\x67\x89\xab\xcd\xef",
-		.klen	= 8,
-		.ptext	= "\x12\x34\x56\x78\x9A\xBC\xDE\xF0"
-			  "\x12\x34\x56\x78\x9A\xBC\xDE\xF0"
-			  "\x12\x34\x56\x78\x9A\xBC\xDE\xF0"
-			  "\x12\x34\x56\x78",
-		.ctext	= "\x66\xa0\x94\x9f\x8a\xf7\xd6\x89"
-			  "\x1f\x7f\x83\x2b\xa8\x33\xc0\x0c"
-			  "\x89\x2e\xbe\x30\x14\x3c\xe2\x87"
-			  "\x40\x01\x1e\xcf",
-		.len	= 28,
-	}, {
-		.key	= "\xef\x01\x23\x45",
-		.klen	= 4,
-		.ptext	= "\x00\x00\x00\x00\x00\x00\x00\x00"
-			  "\x00\x00",
-		.ctext	= "\xd6\xa1\x41\xa7\xec\x3c\x38\xdf"
-			  "\xbd\x61",
-		.len	= 10,
-	}, {
-		.key	= "\x01\x23\x45\x67\x89\xAB\xCD\xEF"
-			"\x00\x00\x00\x00\x00\x00\x00\x00",
-		.klen	= 16,
-		.ptext	= "\x01\x23\x45\x67\x89\xAB\xCD\xEF",
-		.ctext	= "\x69\x72\x36\x59\x1B\x52\x42\xB1",
-		.len	= 8,
-	},
-};
-
 /*
  * TEA test vectors
  */
-- 
2.17.1


^ permalink raw reply related	[flat|nested] 17+ messages in thread

* Re: [RFC PATCH 1/7] staging/rtl8192e: switch to RC4 library interface
  2020-07-02 10:19 ` [RFC PATCH 1/7] staging/rtl8192e: switch to RC4 library interface Ard Biesheuvel
@ 2020-07-02 10:32   ` Greg Kroah-Hartman
  0 siblings, 0 replies; 17+ messages in thread
From: Greg Kroah-Hartman @ 2020-07-02 10:32 UTC (permalink / raw)
  To: Ard Biesheuvel
  Cc: linux-kernel, devel, linux-nfs, Herbert Xu, Eric Biggers,
	David S. Miller, J. Bruce Fields, Chuck Lever, linux-crypto,
	netdev, Anna Schumaker, Trond Myklebust

On Thu, Jul 02, 2020 at 12:19:41PM +0200, Ard Biesheuvel wrote:
> Switch to the ARC4 library interface, to remove the pointless
> dependency on the skcipher API, from which we will hopefully be
> able to drop ecb(arc4) skcipher support.
> 
> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

^ permalink raw reply	[flat|nested] 17+ messages in thread

* Re: [RFC PATCH 2/7] staging/rtl8192u: switch to RC4 library interface
  2020-07-02 10:19 ` [RFC PATCH 2/7] staging/rtl8192u: " Ard Biesheuvel
@ 2020-07-02 10:32   ` Greg Kroah-Hartman
  0 siblings, 0 replies; 17+ messages in thread
From: Greg Kroah-Hartman @ 2020-07-02 10:32 UTC (permalink / raw)
  To: Ard Biesheuvel
  Cc: linux-kernel, devel, linux-nfs, Herbert Xu, Eric Biggers,
	David S. Miller, J. Bruce Fields, Chuck Lever, linux-crypto,
	netdev, Anna Schumaker, Trond Myklebust

On Thu, Jul 02, 2020 at 12:19:42PM +0200, Ard Biesheuvel wrote:
> Switch to the ARC4 library interface, to remove the pointless
> dependency on the skcipher API, from which we will hopefully be
> able to drop ecb(arc4) skcipher support.
> 
> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

^ permalink raw reply	[flat|nested] 17+ messages in thread

* Re: [RFC PATCH 3/7] SUNRPC: remove RC4-HMAC-MD5 support from KerberosV
  2020-07-02 10:19 ` [RFC PATCH 3/7] SUNRPC: remove RC4-HMAC-MD5 support from KerberosV Ard Biesheuvel
@ 2020-07-02 15:49   ` J. Bruce Fields
  0 siblings, 0 replies; 17+ messages in thread
From: J. Bruce Fields @ 2020-07-02 15:49 UTC (permalink / raw)
  To: Ard Biesheuvel
  Cc: linux-kernel, Herbert Xu, David S. Miller, Greg Kroah-Hartman,
	Trond Myklebust, Anna Schumaker, Chuck Lever, Eric Biggers,
	linux-crypto, netdev, devel, linux-nfs, smayhew, bcoddings

Acked-by: J. Bruce Fields <bfields@redhat.com>

On Thu, Jul 02, 2020 at 12:19:43PM +0200, Ard Biesheuvel wrote:
> The RC4-HMAC-MD5 KerberosV algorithm is based on RFC 4757 [0], which
> was specifically issued for interoperability with Windows 2000, but was
> never intended to receive the same level of support. The RFC says
> 
>   The IETF Kerberos community supports publishing this specification as
>   an informational document in order to describe this widely
>   implemented technology.  However, while these encryption types
>   provide the operations necessary to implement the base Kerberos
>   specification [RFC4120], they do not provide all the required
>   operations in the Kerberos cryptography framework [RFC3961].  As a
>   result, it is not generally possible to implement potential
>   extensions to Kerberos using these encryption types.  The Kerberos
>   encryption type negotiation mechanism [RFC4537] provides one approach
>   for using such extensions even when a Kerberos infrastructure uses
>   long-term RC4 keys.  Because this specification does not implement
>   operations required by RFC 3961 and because of security concerns with
>   the use of RC4 and MD4 discussed in Section 8, this specification is
>   not appropriate for publication on the standards track.
> 
>   The RC4-HMAC encryption types are used to ease upgrade of existing
>   Windows NT environments, provide strong cryptography (128-bit key
>   lengths), and provide exportable (meet United States government
>   export restriction requirements) encryption.  This document describes
>   the implementation of those encryption types.
> 
> Furthermore, this RFC was re-classified as 'historic' by RFC 8429 [1] in
> 2018, stating that 'none of the encryption types it specifies should be
> used'
> 
> Note that other outdated algorithms are left in place (some of which are
> guarded by CONFIG_SUNRPC_DISABLE_INSECURE_ENCTYPES), so this should only
> adversely affect interoperability with Windows NT/2000 systems that have
> not received any updates since 2008 (but are connected to a network
> nonetheless)
> 
> [0] https://tools.ietf.org/html/rfc4757
> [1] https://tools.ietf.org/html/rfc8429
> 
> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
> ---
>  include/linux/sunrpc/gss_krb5.h          |  11 -
>  include/linux/sunrpc/gss_krb5_enctypes.h |   9 +-
>  net/sunrpc/Kconfig                       |   1 -
>  net/sunrpc/auth_gss/gss_krb5_crypto.c    | 276 --------------------
>  net/sunrpc/auth_gss/gss_krb5_mech.c      |  95 -------
>  net/sunrpc/auth_gss/gss_krb5_seal.c      |   1 -
>  net/sunrpc/auth_gss/gss_krb5_seqnum.c    |  87 ------
>  net/sunrpc/auth_gss/gss_krb5_unseal.c    |   1 -
>  net/sunrpc/auth_gss/gss_krb5_wrap.c      |  65 +----
>  9 files changed, 16 insertions(+), 530 deletions(-)
> 
> diff --git a/include/linux/sunrpc/gss_krb5.h b/include/linux/sunrpc/gss_krb5.h
> index e8f8ffe7448b..91f43d86879d 100644
> --- a/include/linux/sunrpc/gss_krb5.h
> +++ b/include/linux/sunrpc/gss_krb5.h
> @@ -141,14 +141,12 @@ enum sgn_alg {
>  	SGN_ALG_MD2_5 = 0x0001,
>  	SGN_ALG_DES_MAC = 0x0002,
>  	SGN_ALG_3 = 0x0003,		/* not published */
> -	SGN_ALG_HMAC_MD5 = 0x0011,	/* microsoft w2k; no support */
>  	SGN_ALG_HMAC_SHA1_DES3_KD = 0x0004
>  };
>  enum seal_alg {
>  	SEAL_ALG_NONE = 0xffff,
>  	SEAL_ALG_DES = 0x0000,
>  	SEAL_ALG_1 = 0x0001,		/* not published */
> -	SEAL_ALG_MICROSOFT_RC4 = 0x0010,/* microsoft w2k; no support */
>  	SEAL_ALG_DES3KD = 0x0002
>  };
>  
> @@ -316,14 +314,5 @@ gss_krb5_aes_decrypt(struct krb5_ctx *kctx, u32 offset, u32 len,
>  		     struct xdr_buf *buf, u32 *plainoffset,
>  		     u32 *plainlen);
>  
> -int
> -krb5_rc4_setup_seq_key(struct krb5_ctx *kctx,
> -		       struct crypto_sync_skcipher *cipher,
> -		       unsigned char *cksum);
> -
> -int
> -krb5_rc4_setup_enc_key(struct krb5_ctx *kctx,
> -		       struct crypto_sync_skcipher *cipher,
> -		       s32 seqnum);
>  void
>  gss_krb5_make_confounder(char *p, u32 conflen);
> diff --git a/include/linux/sunrpc/gss_krb5_enctypes.h b/include/linux/sunrpc/gss_krb5_enctypes.h
> index 981c89cef19d..87eea679d750 100644
> --- a/include/linux/sunrpc/gss_krb5_enctypes.h
> +++ b/include/linux/sunrpc/gss_krb5_enctypes.h
> @@ -13,15 +13,13 @@
>  #ifdef CONFIG_SUNRPC_DISABLE_INSECURE_ENCTYPES
>  
>  /*
> - * NB: This list includes encryption types that were deprecated
> - * by RFC 8429 (DES3_CBC_SHA1 and ARCFOUR_HMAC).
> + * NB: This list includes DES3_CBC_SHA1, which was deprecated by RFC 8429.
>   *
>   * ENCTYPE_AES256_CTS_HMAC_SHA1_96
>   * ENCTYPE_AES128_CTS_HMAC_SHA1_96
>   * ENCTYPE_DES3_CBC_SHA1
> - * ENCTYPE_ARCFOUR_HMAC
>   */
> -#define KRB5_SUPPORTED_ENCTYPES "18,17,16,23"
> +#define KRB5_SUPPORTED_ENCTYPES "18,17,16"
>  
>  #else	/* CONFIG_SUNRPC_DISABLE_INSECURE_ENCTYPES */
>  
> @@ -32,12 +30,11 @@
>   * ENCTYPE_AES256_CTS_HMAC_SHA1_96
>   * ENCTYPE_AES128_CTS_HMAC_SHA1_96
>   * ENCTYPE_DES3_CBC_SHA1
> - * ENCTYPE_ARCFOUR_HMAC
>   * ENCTYPE_DES_CBC_MD5
>   * ENCTYPE_DES_CBC_CRC
>   * ENCTYPE_DES_CBC_MD4
>   */
> -#define KRB5_SUPPORTED_ENCTYPES "18,17,16,23,3,1,2"
> +#define KRB5_SUPPORTED_ENCTYPES "18,17,16,3,1,2"
>  
>  #endif	/* CONFIG_SUNRPC_DISABLE_INSECURE_ENCTYPES */
>  
> diff --git a/net/sunrpc/Kconfig b/net/sunrpc/Kconfig
> index 3bcf985507be..bbbb5af0af13 100644
> --- a/net/sunrpc/Kconfig
> +++ b/net/sunrpc/Kconfig
> @@ -21,7 +21,6 @@ config RPCSEC_GSS_KRB5
>  	depends on SUNRPC && CRYPTO
>  	depends on CRYPTO_MD5 && CRYPTO_DES && CRYPTO_CBC && CRYPTO_CTS
>  	depends on CRYPTO_ECB && CRYPTO_HMAC && CRYPTO_SHA1 && CRYPTO_AES
> -	depends on CRYPTO_ARC4
>  	default y
>  	select SUNRPC_GSS
>  	help
> diff --git a/net/sunrpc/auth_gss/gss_krb5_crypto.c b/net/sunrpc/auth_gss/gss_krb5_crypto.c
> index e7180da1fc6a..634b6c6e0dcb 100644
> --- a/net/sunrpc/auth_gss/gss_krb5_crypto.c
> +++ b/net/sunrpc/auth_gss/gss_krb5_crypto.c
> @@ -138,135 +138,6 @@ checksummer(struct scatterlist *sg, void *data)
>  	return crypto_ahash_update(req);
>  }
>  
> -static int
> -arcfour_hmac_md5_usage_to_salt(unsigned int usage, u8 salt[4])
> -{
> -	unsigned int ms_usage;
> -
> -	switch (usage) {
> -	case KG_USAGE_SIGN:
> -		ms_usage = 15;
> -		break;
> -	case KG_USAGE_SEAL:
> -		ms_usage = 13;
> -		break;
> -	default:
> -		return -EINVAL;
> -	}
> -	salt[0] = (ms_usage >> 0) & 0xff;
> -	salt[1] = (ms_usage >> 8) & 0xff;
> -	salt[2] = (ms_usage >> 16) & 0xff;
> -	salt[3] = (ms_usage >> 24) & 0xff;
> -
> -	return 0;
> -}
> -
> -static u32
> -make_checksum_hmac_md5(struct krb5_ctx *kctx, char *header, int hdrlen,
> -		       struct xdr_buf *body, int body_offset, u8 *cksumkey,
> -		       unsigned int usage, struct xdr_netobj *cksumout)
> -{
> -	struct scatterlist              sg[1];
> -	int err = -1;
> -	u8 *checksumdata;
> -	u8 *rc4salt;
> -	struct crypto_ahash *md5;
> -	struct crypto_ahash *hmac_md5;
> -	struct ahash_request *req;
> -
> -	if (cksumkey == NULL)
> -		return GSS_S_FAILURE;
> -
> -	if (cksumout->len < kctx->gk5e->cksumlength) {
> -		dprintk("%s: checksum buffer length, %u, too small for %s\n",
> -			__func__, cksumout->len, kctx->gk5e->name);
> -		return GSS_S_FAILURE;
> -	}
> -
> -	rc4salt = kmalloc_array(4, sizeof(*rc4salt), GFP_NOFS);
> -	if (!rc4salt)
> -		return GSS_S_FAILURE;
> -
> -	if (arcfour_hmac_md5_usage_to_salt(usage, rc4salt)) {
> -		dprintk("%s: invalid usage value %u\n", __func__, usage);
> -		goto out_free_rc4salt;
> -	}
> -
> -	checksumdata = kmalloc(GSS_KRB5_MAX_CKSUM_LEN, GFP_NOFS);
> -	if (!checksumdata)
> -		goto out_free_rc4salt;
> -
> -	md5 = crypto_alloc_ahash("md5", 0, CRYPTO_ALG_ASYNC);
> -	if (IS_ERR(md5))
> -		goto out_free_cksum;
> -
> -	hmac_md5 = crypto_alloc_ahash(kctx->gk5e->cksum_name, 0,
> -				      CRYPTO_ALG_ASYNC);
> -	if (IS_ERR(hmac_md5))
> -		goto out_free_md5;
> -
> -	req = ahash_request_alloc(md5, GFP_NOFS);
> -	if (!req)
> -		goto out_free_hmac_md5;
> -
> -	ahash_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP, NULL, NULL);
> -
> -	err = crypto_ahash_init(req);
> -	if (err)
> -		goto out;
> -	sg_init_one(sg, rc4salt, 4);
> -	ahash_request_set_crypt(req, sg, NULL, 4);
> -	err = crypto_ahash_update(req);
> -	if (err)
> -		goto out;
> -
> -	sg_init_one(sg, header, hdrlen);
> -	ahash_request_set_crypt(req, sg, NULL, hdrlen);
> -	err = crypto_ahash_update(req);
> -	if (err)
> -		goto out;
> -	err = xdr_process_buf(body, body_offset, body->len - body_offset,
> -			      checksummer, req);
> -	if (err)
> -		goto out;
> -	ahash_request_set_crypt(req, NULL, checksumdata, 0);
> -	err = crypto_ahash_final(req);
> -	if (err)
> -		goto out;
> -
> -	ahash_request_free(req);
> -	req = ahash_request_alloc(hmac_md5, GFP_NOFS);
> -	if (!req)
> -		goto out_free_hmac_md5;
> -
> -	ahash_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP, NULL, NULL);
> -
> -	err = crypto_ahash_setkey(hmac_md5, cksumkey, kctx->gk5e->keylength);
> -	if (err)
> -		goto out;
> -
> -	sg_init_one(sg, checksumdata, crypto_ahash_digestsize(md5));
> -	ahash_request_set_crypt(req, sg, checksumdata,
> -				crypto_ahash_digestsize(md5));
> -	err = crypto_ahash_digest(req);
> -	if (err)
> -		goto out;
> -
> -	memcpy(cksumout->data, checksumdata, kctx->gk5e->cksumlength);
> -	cksumout->len = kctx->gk5e->cksumlength;
> -out:
> -	ahash_request_free(req);
> -out_free_hmac_md5:
> -	crypto_free_ahash(hmac_md5);
> -out_free_md5:
> -	crypto_free_ahash(md5);
> -out_free_cksum:
> -	kfree(checksumdata);
> -out_free_rc4salt:
> -	kfree(rc4salt);
> -	return err ? GSS_S_FAILURE : 0;
> -}
> -
>  /*
>   * checksum the plaintext data and hdrlen bytes of the token header
>   * The checksum is performed over the first 8 bytes of the
> @@ -284,11 +155,6 @@ make_checksum(struct krb5_ctx *kctx, char *header, int hdrlen,
>  	u8 *checksumdata;
>  	unsigned int checksumlen;
>  
> -	if (kctx->gk5e->ctype == CKSUMTYPE_HMAC_MD5_ARCFOUR)
> -		return make_checksum_hmac_md5(kctx, header, hdrlen,
> -					      body, body_offset,
> -					      cksumkey, usage, cksumout);
> -
>  	if (cksumout->len < kctx->gk5e->cksumlength) {
>  		dprintk("%s: checksum buffer length, %u, too small for %s\n",
>  			__func__, cksumout->len, kctx->gk5e->name);
> @@ -942,145 +808,3 @@ gss_krb5_aes_decrypt(struct krb5_ctx *kctx, u32 offset, u32 len,
>  		ret = GSS_S_FAILURE;
>  	return ret;
>  }
> -
> -/*
> - * Compute Kseq given the initial session key and the checksum.
> - * Set the key of the given cipher.
> - */
> -int
> -krb5_rc4_setup_seq_key(struct krb5_ctx *kctx,
> -		       struct crypto_sync_skcipher *cipher,
> -		       unsigned char *cksum)
> -{
> -	struct crypto_shash *hmac;
> -	struct shash_desc *desc;
> -	u8 Kseq[GSS_KRB5_MAX_KEYLEN];
> -	u32 zeroconstant = 0;
> -	int err;
> -
> -	dprintk("%s: entered\n", __func__);
> -
> -	hmac = crypto_alloc_shash(kctx->gk5e->cksum_name, 0, 0);
> -	if (IS_ERR(hmac)) {
> -		dprintk("%s: error %ld, allocating hash '%s'\n",
> -			__func__, PTR_ERR(hmac), kctx->gk5e->cksum_name);
> -		return PTR_ERR(hmac);
> -	}
> -
> -	desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(hmac),
> -		       GFP_NOFS);
> -	if (!desc) {
> -		dprintk("%s: failed to allocate shash descriptor for '%s'\n",
> -			__func__, kctx->gk5e->cksum_name);
> -		crypto_free_shash(hmac);
> -		return -ENOMEM;
> -	}
> -
> -	desc->tfm = hmac;
> -
> -	/* Compute intermediate Kseq from session key */
> -	err = crypto_shash_setkey(hmac, kctx->Ksess, kctx->gk5e->keylength);
> -	if (err)
> -		goto out_err;
> -
> -	err = crypto_shash_digest(desc, (u8 *)&zeroconstant, 4, Kseq);
> -	if (err)
> -		goto out_err;
> -
> -	/* Compute final Kseq from the checksum and intermediate Kseq */
> -	err = crypto_shash_setkey(hmac, Kseq, kctx->gk5e->keylength);
> -	if (err)
> -		goto out_err;
> -
> -	err = crypto_shash_digest(desc, cksum, 8, Kseq);
> -	if (err)
> -		goto out_err;
> -
> -	err = crypto_sync_skcipher_setkey(cipher, Kseq, kctx->gk5e->keylength);
> -	if (err)
> -		goto out_err;
> -
> -	err = 0;
> -
> -out_err:
> -	kzfree(desc);
> -	crypto_free_shash(hmac);
> -	dprintk("%s: returning %d\n", __func__, err);
> -	return err;
> -}
> -
> -/*
> - * Compute Kcrypt given the initial session key and the plaintext seqnum.
> - * Set the key of cipher kctx->enc.
> - */
> -int
> -krb5_rc4_setup_enc_key(struct krb5_ctx *kctx,
> -		       struct crypto_sync_skcipher *cipher,
> -		       s32 seqnum)
> -{
> -	struct crypto_shash *hmac;
> -	struct shash_desc *desc;
> -	u8 Kcrypt[GSS_KRB5_MAX_KEYLEN];
> -	u8 zeroconstant[4] = {0};
> -	u8 seqnumarray[4];
> -	int err, i;
> -
> -	dprintk("%s: entered, seqnum %u\n", __func__, seqnum);
> -
> -	hmac = crypto_alloc_shash(kctx->gk5e->cksum_name, 0, 0);
> -	if (IS_ERR(hmac)) {
> -		dprintk("%s: error %ld, allocating hash '%s'\n",
> -			__func__, PTR_ERR(hmac), kctx->gk5e->cksum_name);
> -		return PTR_ERR(hmac);
> -	}
> -
> -	desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(hmac),
> -		       GFP_NOFS);
> -	if (!desc) {
> -		dprintk("%s: failed to allocate shash descriptor for '%s'\n",
> -			__func__, kctx->gk5e->cksum_name);
> -		crypto_free_shash(hmac);
> -		return -ENOMEM;
> -	}
> -
> -	desc->tfm = hmac;
> -
> -	/* Compute intermediate Kcrypt from session key */
> -	for (i = 0; i < kctx->gk5e->keylength; i++)
> -		Kcrypt[i] = kctx->Ksess[i] ^ 0xf0;
> -
> -	err = crypto_shash_setkey(hmac, Kcrypt, kctx->gk5e->keylength);
> -	if (err)
> -		goto out_err;
> -
> -	err = crypto_shash_digest(desc, zeroconstant, 4, Kcrypt);
> -	if (err)
> -		goto out_err;
> -
> -	/* Compute final Kcrypt from the seqnum and intermediate Kcrypt */
> -	err = crypto_shash_setkey(hmac, Kcrypt, kctx->gk5e->keylength);
> -	if (err)
> -		goto out_err;
> -
> -	seqnumarray[0] = (unsigned char) ((seqnum >> 24) & 0xff);
> -	seqnumarray[1] = (unsigned char) ((seqnum >> 16) & 0xff);
> -	seqnumarray[2] = (unsigned char) ((seqnum >> 8) & 0xff);
> -	seqnumarray[3] = (unsigned char) ((seqnum >> 0) & 0xff);
> -
> -	err = crypto_shash_digest(desc, seqnumarray, 4, Kcrypt);
> -	if (err)
> -		goto out_err;
> -
> -	err = crypto_sync_skcipher_setkey(cipher, Kcrypt,
> -					  kctx->gk5e->keylength);
> -	if (err)
> -		goto out_err;
> -
> -	err = 0;
> -
> -out_err:
> -	kzfree(desc);
> -	crypto_free_shash(hmac);
> -	dprintk("%s: returning %d\n", __func__, err);
> -	return err;
> -}
> diff --git a/net/sunrpc/auth_gss/gss_krb5_mech.c b/net/sunrpc/auth_gss/gss_krb5_mech.c
> index 75b3c2e9e8f8..ae9acf3a7389 100644
> --- a/net/sunrpc/auth_gss/gss_krb5_mech.c
> +++ b/net/sunrpc/auth_gss/gss_krb5_mech.c
> @@ -51,27 +51,6 @@ static const struct gss_krb5_enctype supported_gss_krb5_enctypes[] = {
>  	  .keyed_cksum = 0,
>  	},
>  #endif	/* CONFIG_SUNRPC_DISABLE_INSECURE_ENCTYPES */
> -	/*
> -	 * RC4-HMAC
> -	 */
> -	{
> -	  .etype = ENCTYPE_ARCFOUR_HMAC,
> -	  .ctype = CKSUMTYPE_HMAC_MD5_ARCFOUR,
> -	  .name = "rc4-hmac",
> -	  .encrypt_name = "ecb(arc4)",
> -	  .cksum_name = "hmac(md5)",
> -	  .encrypt = krb5_encrypt,
> -	  .decrypt = krb5_decrypt,
> -	  .mk_key = NULL,
> -	  .signalg = SGN_ALG_HMAC_MD5,
> -	  .sealalg = SEAL_ALG_MICROSOFT_RC4,
> -	  .keybytes = 16,
> -	  .keylength = 16,
> -	  .blocksize = 1,
> -	  .conflen = 8,
> -	  .cksumlength = 8,
> -	  .keyed_cksum = 1,
> -	},
>  	/*
>  	 * 3DES
>  	 */
> @@ -401,78 +380,6 @@ context_derive_keys_des3(struct krb5_ctx *ctx, gfp_t gfp_mask)
>  	return -EINVAL;
>  }
>  
> -/*
> - * Note that RC4 depends on deriving keys using the sequence
> - * number or the checksum of a token.  Therefore, the final keys
> - * cannot be calculated until the token is being constructed!
> - */
> -static int
> -context_derive_keys_rc4(struct krb5_ctx *ctx)
> -{
> -	struct crypto_shash *hmac;
> -	char sigkeyconstant[] = "signaturekey";
> -	int slen = strlen(sigkeyconstant) + 1;	/* include null terminator */
> -	struct shash_desc *desc;
> -	int err;
> -
> -	dprintk("RPC:       %s: entered\n", __func__);
> -	/*
> -	 * derive cksum (aka Ksign) key
> -	 */
> -	hmac = crypto_alloc_shash(ctx->gk5e->cksum_name, 0, 0);
> -	if (IS_ERR(hmac)) {
> -		dprintk("%s: error %ld allocating hash '%s'\n",
> -			__func__, PTR_ERR(hmac), ctx->gk5e->cksum_name);
> -		err = PTR_ERR(hmac);
> -		goto out_err;
> -	}
> -
> -	err = crypto_shash_setkey(hmac, ctx->Ksess, ctx->gk5e->keylength);
> -	if (err)
> -		goto out_err_free_hmac;
> -
> -
> -	desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(hmac), GFP_NOFS);
> -	if (!desc) {
> -		dprintk("%s: failed to allocate hash descriptor for '%s'\n",
> -			__func__, ctx->gk5e->cksum_name);
> -		err = -ENOMEM;
> -		goto out_err_free_hmac;
> -	}
> -
> -	desc->tfm = hmac;
> -
> -	err = crypto_shash_digest(desc, sigkeyconstant, slen, ctx->cksum);
> -	kzfree(desc);
> -	if (err)
> -		goto out_err_free_hmac;
> -	/*
> -	 * allocate hash, and skciphers for data and seqnum encryption
> -	 */
> -	ctx->enc = crypto_alloc_sync_skcipher(ctx->gk5e->encrypt_name, 0, 0);
> -	if (IS_ERR(ctx->enc)) {
> -		err = PTR_ERR(ctx->enc);
> -		goto out_err_free_hmac;
> -	}
> -
> -	ctx->seq = crypto_alloc_sync_skcipher(ctx->gk5e->encrypt_name, 0, 0);
> -	if (IS_ERR(ctx->seq)) {
> -		crypto_free_sync_skcipher(ctx->enc);
> -		err = PTR_ERR(ctx->seq);
> -		goto out_err_free_hmac;
> -	}
> -
> -	dprintk("RPC:       %s: returning success\n", __func__);
> -
> -	err = 0;
> -
> -out_err_free_hmac:
> -	crypto_free_shash(hmac);
> -out_err:
> -	dprintk("RPC:       %s: returning %d\n", __func__, err);
> -	return err;
> -}
> -
>  static int
>  context_derive_keys_new(struct krb5_ctx *ctx, gfp_t gfp_mask)
>  {
> @@ -649,8 +556,6 @@ gss_import_v2_context(const void *p, const void *end, struct krb5_ctx *ctx,
>  	switch (ctx->enctype) {
>  	case ENCTYPE_DES3_CBC_RAW:
>  		return context_derive_keys_des3(ctx, gfp_mask);
> -	case ENCTYPE_ARCFOUR_HMAC:
> -		return context_derive_keys_rc4(ctx);
>  	case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
>  	case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
>  		return context_derive_keys_new(ctx, gfp_mask);
> diff --git a/net/sunrpc/auth_gss/gss_krb5_seal.c b/net/sunrpc/auth_gss/gss_krb5_seal.c
> index f1d280accf43..33061417ec97 100644
> --- a/net/sunrpc/auth_gss/gss_krb5_seal.c
> +++ b/net/sunrpc/auth_gss/gss_krb5_seal.c
> @@ -214,7 +214,6 @@ gss_get_mic_kerberos(struct gss_ctx *gss_ctx, struct xdr_buf *text,
>  		BUG();
>  	case ENCTYPE_DES_CBC_RAW:
>  	case ENCTYPE_DES3_CBC_RAW:
> -	case ENCTYPE_ARCFOUR_HMAC:
>  		return gss_get_mic_v1(ctx, text, token);
>  	case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
>  	case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
> diff --git a/net/sunrpc/auth_gss/gss_krb5_seqnum.c b/net/sunrpc/auth_gss/gss_krb5_seqnum.c
> index 507105127095..fb117817ff5d 100644
> --- a/net/sunrpc/auth_gss/gss_krb5_seqnum.c
> +++ b/net/sunrpc/auth_gss/gss_krb5_seqnum.c
> @@ -39,42 +39,6 @@
>  # define RPCDBG_FACILITY        RPCDBG_AUTH
>  #endif
>  
> -static s32
> -krb5_make_rc4_seq_num(struct krb5_ctx *kctx, int direction, s32 seqnum,
> -		      unsigned char *cksum, unsigned char *buf)
> -{
> -	struct crypto_sync_skcipher *cipher;
> -	unsigned char *plain;
> -	s32 code;
> -
> -	dprintk("RPC:       %s:\n", __func__);
> -	cipher = crypto_alloc_sync_skcipher(kctx->gk5e->encrypt_name, 0, 0);
> -	if (IS_ERR(cipher))
> -		return PTR_ERR(cipher);
> -
> -	plain = kmalloc(8, GFP_NOFS);
> -	if (!plain)
> -		return -ENOMEM;
> -
> -	plain[0] = (unsigned char) ((seqnum >> 24) & 0xff);
> -	plain[1] = (unsigned char) ((seqnum >> 16) & 0xff);
> -	plain[2] = (unsigned char) ((seqnum >> 8) & 0xff);
> -	plain[3] = (unsigned char) ((seqnum >> 0) & 0xff);
> -	plain[4] = direction;
> -	plain[5] = direction;
> -	plain[6] = direction;
> -	plain[7] = direction;
> -
> -	code = krb5_rc4_setup_seq_key(kctx, cipher, cksum);
> -	if (code)
> -		goto out;
> -
> -	code = krb5_encrypt(cipher, cksum, plain, buf, 8);
> -out:
> -	kfree(plain);
> -	crypto_free_sync_skcipher(cipher);
> -	return code;
> -}
>  s32
>  krb5_make_seq_num(struct krb5_ctx *kctx,
>  		struct crypto_sync_skcipher *key,
> @@ -85,10 +49,6 @@ krb5_make_seq_num(struct krb5_ctx *kctx,
>  	unsigned char *plain;
>  	s32 code;
>  
> -	if (kctx->enctype == ENCTYPE_ARCFOUR_HMAC)
> -		return krb5_make_rc4_seq_num(kctx, direction, seqnum,
> -					     cksum, buf);
> -
>  	plain = kmalloc(8, GFP_NOFS);
>  	if (!plain)
>  		return -ENOMEM;
> @@ -108,50 +68,6 @@ krb5_make_seq_num(struct krb5_ctx *kctx,
>  	return code;
>  }
>  
> -static s32
> -krb5_get_rc4_seq_num(struct krb5_ctx *kctx, unsigned char *cksum,
> -		     unsigned char *buf, int *direction, s32 *seqnum)
> -{
> -	struct crypto_sync_skcipher *cipher;
> -	unsigned char *plain;
> -	s32 code;
> -
> -	dprintk("RPC:       %s:\n", __func__);
> -	cipher = crypto_alloc_sync_skcipher(kctx->gk5e->encrypt_name, 0, 0);
> -	if (IS_ERR(cipher))
> -		return PTR_ERR(cipher);
> -
> -	code = krb5_rc4_setup_seq_key(kctx, cipher, cksum);
> -	if (code)
> -		goto out;
> -
> -	plain = kmalloc(8, GFP_NOFS);
> -	if (!plain) {
> -		code = -ENOMEM;
> -		goto out;
> -	}
> -
> -	code = krb5_decrypt(cipher, cksum, buf, plain, 8);
> -	if (code)
> -		goto out_plain;
> -
> -	if ((plain[4] != plain[5]) || (plain[4] != plain[6])
> -				   || (plain[4] != plain[7])) {
> -		code = (s32)KG_BAD_SEQ;
> -		goto out_plain;
> -	}
> -
> -	*direction = plain[4];
> -
> -	*seqnum = ((plain[0] << 24) | (plain[1] << 16) |
> -					(plain[2] << 8) | (plain[3]));
> -out_plain:
> -	kfree(plain);
> -out:
> -	crypto_free_sync_skcipher(cipher);
> -	return code;
> -}
> -
>  s32
>  krb5_get_seq_num(struct krb5_ctx *kctx,
>  	       unsigned char *cksum,
> @@ -164,9 +80,6 @@ krb5_get_seq_num(struct krb5_ctx *kctx,
>  
>  	dprintk("RPC:       krb5_get_seq_num:\n");
>  
> -	if (kctx->enctype == ENCTYPE_ARCFOUR_HMAC)
> -		return krb5_get_rc4_seq_num(kctx, cksum, buf,
> -					    direction, seqnum);
>  	plain = kmalloc(8, GFP_NOFS);
>  	if (!plain)
>  		return -ENOMEM;
> diff --git a/net/sunrpc/auth_gss/gss_krb5_unseal.c b/net/sunrpc/auth_gss/gss_krb5_unseal.c
> index aaab91cf24c8..ba04e3ec970a 100644
> --- a/net/sunrpc/auth_gss/gss_krb5_unseal.c
> +++ b/net/sunrpc/auth_gss/gss_krb5_unseal.c
> @@ -218,7 +218,6 @@ gss_verify_mic_kerberos(struct gss_ctx *gss_ctx,
>  		BUG();
>  	case ENCTYPE_DES_CBC_RAW:
>  	case ENCTYPE_DES3_CBC_RAW:
> -	case ENCTYPE_ARCFOUR_HMAC:
>  		return gss_verify_mic_v1(ctx, message_buffer, read_token);
>  	case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
>  	case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
> diff --git a/net/sunrpc/auth_gss/gss_krb5_wrap.c b/net/sunrpc/auth_gss/gss_krb5_wrap.c
> index cf0fd170ac18..a412a734ee17 100644
> --- a/net/sunrpc/auth_gss/gss_krb5_wrap.c
> +++ b/net/sunrpc/auth_gss/gss_krb5_wrap.c
> @@ -236,26 +236,9 @@ gss_wrap_kerberos_v1(struct krb5_ctx *kctx, int offset,
>  			       seq_send, ptr + GSS_KRB5_TOK_HDR_LEN, ptr + 8)))
>  		return GSS_S_FAILURE;
>  
> -	if (kctx->enctype == ENCTYPE_ARCFOUR_HMAC) {
> -		struct crypto_sync_skcipher *cipher;
> -		int err;
> -		cipher = crypto_alloc_sync_skcipher(kctx->gk5e->encrypt_name,
> -						    0, 0);
> -		if (IS_ERR(cipher))
> -			return GSS_S_FAILURE;
> -
> -		krb5_rc4_setup_enc_key(kctx, cipher, seq_send);
> -
> -		err = gss_encrypt_xdr_buf(cipher, buf,
> -					  offset + headlen - conflen, pages);
> -		crypto_free_sync_skcipher(cipher);
> -		if (err)
> -			return GSS_S_FAILURE;
> -	} else {
> -		if (gss_encrypt_xdr_buf(kctx->enc, buf,
> -					offset + headlen - conflen, pages))
> -			return GSS_S_FAILURE;
> -	}
> +	if (gss_encrypt_xdr_buf(kctx->enc, buf,
> +				offset + headlen - conflen, pages))
> +		return GSS_S_FAILURE;
>  
>  	return (kctx->endtime < now) ? GSS_S_CONTEXT_EXPIRED : GSS_S_COMPLETE;
>  }
> @@ -316,37 +299,9 @@ gss_unwrap_kerberos_v1(struct krb5_ctx *kctx, int offset, int len,
>  	crypt_offset = ptr + (GSS_KRB5_TOK_HDR_LEN + kctx->gk5e->cksumlength) -
>  					(unsigned char *)buf->head[0].iov_base;
>  
> -	/*
> -	 * Need plaintext seqnum to derive encryption key for arcfour-hmac
> -	 */
> -	if (krb5_get_seq_num(kctx, ptr + GSS_KRB5_TOK_HDR_LEN,
> -			     ptr + 8, &direction, &seqnum))
> -		return GSS_S_BAD_SIG;
> -
> -	if ((kctx->initiate && direction != 0xff) ||
> -	    (!kctx->initiate && direction != 0))
> -		return GSS_S_BAD_SIG;
> -
>  	buf->len = len;
> -	if (kctx->enctype == ENCTYPE_ARCFOUR_HMAC) {
> -		struct crypto_sync_skcipher *cipher;
> -		int err;
> -
> -		cipher = crypto_alloc_sync_skcipher(kctx->gk5e->encrypt_name,
> -						    0, 0);
> -		if (IS_ERR(cipher))
> -			return GSS_S_FAILURE;
> -
> -		krb5_rc4_setup_enc_key(kctx, cipher, seqnum);
> -
> -		err = gss_decrypt_xdr_buf(cipher, buf, crypt_offset);
> -		crypto_free_sync_skcipher(cipher);
> -		if (err)
> -			return GSS_S_DEFECTIVE_TOKEN;
> -	} else {
> -		if (gss_decrypt_xdr_buf(kctx->enc, buf, crypt_offset))
> -			return GSS_S_DEFECTIVE_TOKEN;
> -	}
> +	if (gss_decrypt_xdr_buf(kctx->enc, buf, crypt_offset))
> +		return GSS_S_DEFECTIVE_TOKEN;
>  
>  	if (kctx->gk5e->keyed_cksum)
>  		cksumkey = kctx->cksum;
> @@ -370,6 +325,14 @@ gss_unwrap_kerberos_v1(struct krb5_ctx *kctx, int offset, int len,
>  
>  	/* do sequencing checks */
>  
> +	if (krb5_get_seq_num(kctx, ptr + GSS_KRB5_TOK_HDR_LEN,
> +			     ptr + 8, &direction, &seqnum))
> +		return GSS_S_BAD_SIG;
> +
> +	if ((kctx->initiate && direction != 0xff) ||
> +	    (!kctx->initiate && direction != 0))
> +		return GSS_S_BAD_SIG;
> +
>  	/* Copy the data back to the right position.  XXX: Would probably be
>  	 * better to copy and encrypt at the same time. */
>  
> @@ -605,7 +568,6 @@ gss_wrap_kerberos(struct gss_ctx *gctx, int offset,
>  		BUG();
>  	case ENCTYPE_DES_CBC_RAW:
>  	case ENCTYPE_DES3_CBC_RAW:
> -	case ENCTYPE_ARCFOUR_HMAC:
>  		return gss_wrap_kerberos_v1(kctx, offset, buf, pages);
>  	case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
>  	case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
> @@ -624,7 +586,6 @@ gss_unwrap_kerberos(struct gss_ctx *gctx, int offset,
>  		BUG();
>  	case ENCTYPE_DES_CBC_RAW:
>  	case ENCTYPE_DES3_CBC_RAW:
> -	case ENCTYPE_ARCFOUR_HMAC:
>  		return gss_unwrap_kerberos_v1(kctx, offset, len, buf,
>  					      &gctx->slack, &gctx->align);
>  	case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
> -- 
> 2.17.1

^ permalink raw reply	[flat|nested] 17+ messages in thread

* Re: [RFC PATCH 4/7] crypto: remove ARC4 support from the skcipher API
  2020-07-02 10:19 ` [RFC PATCH 4/7] crypto: remove ARC4 support from the skcipher API Ard Biesheuvel
@ 2020-07-02 17:50   ` Eric Biggers
  2020-07-02 18:21     ` Ard Biesheuvel
  0 siblings, 1 reply; 17+ messages in thread
From: Eric Biggers @ 2020-07-02 17:50 UTC (permalink / raw)
  To: Ard Biesheuvel, linux-wireless, Marcel Holtmann, Denis Kenzior
  Cc: linux-kernel, Herbert Xu, David S. Miller, Greg Kroah-Hartman,
	Trond Myklebust, Anna Schumaker, J. Bruce Fields, Chuck Lever,
	linux-crypto, netdev, devel, linux-nfs

[+linux-wireless, Marcel Holtmann, and Denis Kenzior]

On Thu, Jul 02, 2020 at 12:19:44PM +0200, Ard Biesheuvel wrote:
> Remove the generic ecb(arc4) skcipher, which is slightly cumbersome from
> a maintenance perspective, since it does not quite behave like other
> skciphers do in terms of key vs IV lifetime. Since we are leaving the
> library interface in place, which is used by the various WEP and TKIP
> implementations we have in the tree, we can safely drop this code now
> it no longer has any users.
> 
> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

Last year there was a discussion where it was mentioned that iwd uses
"ecb(arc4)" via AF_ALG.  So can we really remove it yet?
See https://lkml.kernel.org/r/97BB95F6-4A4C-4984-9EAB-6069E19B4A4F@holtmann.org
Note that the code isn't in "iwd" itself but rather in "libell" which iwd
depends on: https://git.kernel.org/pub/scm/libs/ell/ell.git/

Apparently it also uses md4 and ecb(des) too.

Marcel and Denis, what's your deprecation plan for these obsolete and insecure
algorithms?

- Eric

^ permalink raw reply	[flat|nested] 17+ messages in thread

* Re: [RFC PATCH 4/7] crypto: remove ARC4 support from the skcipher API
  2020-07-02 17:50   ` Eric Biggers
@ 2020-07-02 18:21     ` Ard Biesheuvel
  2020-07-02 23:04       ` Ard Biesheuvel
  0 siblings, 1 reply; 17+ messages in thread
From: Ard Biesheuvel @ 2020-07-02 18:21 UTC (permalink / raw)
  To: Eric Biggers
  Cc: linux-wireless, Marcel Holtmann, Denis Kenzior,
	Linux Kernel Mailing List, Herbert Xu, David S. Miller,
	Greg Kroah-Hartman, Trond Myklebust, Anna Schumaker,
	J. Bruce Fields, Chuck Lever, Linux Crypto Mailing List, netdev,
	devel, linux-nfs

On Thu, 2 Jul 2020 at 19:50, Eric Biggers <ebiggers@kernel.org> wrote:
>
> [+linux-wireless, Marcel Holtmann, and Denis Kenzior]
>
> On Thu, Jul 02, 2020 at 12:19:44PM +0200, Ard Biesheuvel wrote:
> > Remove the generic ecb(arc4) skcipher, which is slightly cumbersome from
> > a maintenance perspective, since it does not quite behave like other
> > skciphers do in terms of key vs IV lifetime. Since we are leaving the
> > library interface in place, which is used by the various WEP and TKIP
> > implementations we have in the tree, we can safely drop this code now
> > it no longer has any users.
> >
> > Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
>
> Last year there was a discussion where it was mentioned that iwd uses
> "ecb(arc4)" via AF_ALG.  So can we really remove it yet?
> See https://lkml.kernel.org/r/97BB95F6-4A4C-4984-9EAB-6069E19B4A4F@holtmann.org
> Note that the code isn't in "iwd" itself but rather in "libell" which iwd
> depends on: https://git.kernel.org/pub/scm/libs/ell/ell.git/
>
> Apparently it also uses md4 and ecb(des) too.
>

Ah yes, I remember now :-(

> Marcel and Denis, what's your deprecation plan for these obsolete and insecure
> algorithms?
>

Given Denis's statement:

  It sounds to me like it was broken and should be fixed.  So our vote /
  preference is to have ARC4 fixed to follow the proper semantics.  We
  can deal with the kernel behavioral change on our end easily enough;
  the required workarounds are the worse evil.

I would think that an ABI break is not the end of the world for them,
and given how trivial it is to implement RC4 in C, the workaround
should be to simply implement RC4 in user space, and not even bother
trying to use AF_ALG to get at ecb(arc4)

(same applies to md4 and ecb(des) btw)

There will always be a long tail of use cases, and at some point, we
just have to draw the line and remove obsolete and insecure cruft,
especially when it impedes progress on other fronts.



Full implementation of arc4 aka ecb(arc4) below.

void arc4_crypt(struct arc4_ctx *ctx, u8 *out, const u8 *in, unsigned int len)
{
  u32 *const S = ctx->S;
  u32 x, y, a, b;
  u32 ty, ta, tb;

  if (len == 0)
    return;

  x = ctx->x;
  y = ctx->y;

  a = S[x];
  y = (y + a) & 0xff;
  b = S[y];

  do {
    S[y] = a;
    a = (a + b) & 0xff;
    S[x] = b;
    x = (x + 1) & 0xff;
    ta = S[x];
    ty = (y + ta) & 0xff;
    tb = S[ty];
    *out++ = *in++ ^ S[a];
    if (--len == 0)
      break;
    y = ty;
    a = ta;
    b = tb;
  } while (true);

  ctx->x = x;
  ctx->y = y;
}

^ permalink raw reply	[flat|nested] 17+ messages in thread

* Re: [RFC PATCH 4/7] crypto: remove ARC4 support from the skcipher API
  2020-07-02 18:21     ` Ard Biesheuvel
@ 2020-07-02 23:04       ` Ard Biesheuvel
  2020-07-18  8:18         ` Ard Biesheuvel
  0 siblings, 1 reply; 17+ messages in thread
From: Ard Biesheuvel @ 2020-07-02 23:04 UTC (permalink / raw)
  To: Eric Biggers
  Cc: linux-wireless, Marcel Holtmann, Denis Kenzior,
	Linux Kernel Mailing List, Herbert Xu, David S. Miller,
	Greg Kroah-Hartman, Trond Myklebust, Anna Schumaker,
	J. Bruce Fields, Chuck Lever, Linux Crypto Mailing List, netdev,
	devel, linux-nfs

On Thu, 2 Jul 2020 at 20:21, Ard Biesheuvel <ardb@kernel.org> wrote:
>
> On Thu, 2 Jul 2020 at 19:50, Eric Biggers <ebiggers@kernel.org> wrote:
> >
> > [+linux-wireless, Marcel Holtmann, and Denis Kenzior]
> >
> > On Thu, Jul 02, 2020 at 12:19:44PM +0200, Ard Biesheuvel wrote:
> > > Remove the generic ecb(arc4) skcipher, which is slightly cumbersome from
> > > a maintenance perspective, since it does not quite behave like other
> > > skciphers do in terms of key vs IV lifetime. Since we are leaving the
> > > library interface in place, which is used by the various WEP and TKIP
> > > implementations we have in the tree, we can safely drop this code now
> > > it no longer has any users.
> > >
> > > Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
> >
> > Last year there was a discussion where it was mentioned that iwd uses
> > "ecb(arc4)" via AF_ALG.  So can we really remove it yet?
> > See https://lkml.kernel.org/r/97BB95F6-4A4C-4984-9EAB-6069E19B4A4F@holtmann.org
> > Note that the code isn't in "iwd" itself but rather in "libell" which iwd
> > depends on: https://git.kernel.org/pub/scm/libs/ell/ell.git/
> >
> > Apparently it also uses md4 and ecb(des) too.
> >
>
> Ah yes, I remember now :-(
>
> > Marcel and Denis, what's your deprecation plan for these obsolete and insecure
> > algorithms?
> >
>
> Given Denis's statement:
>
>   It sounds to me like it was broken and should be fixed.  So our vote /
>   preference is to have ARC4 fixed to follow the proper semantics.  We
>   can deal with the kernel behavioral change on our end easily enough;
>   the required workarounds are the worse evil.
>
> I would think that an ABI break is not the end of the world for them,
> and given how trivial it is to implement RC4 in C, the workaround
> should be to simply implement RC4 in user space, and not even bother
> trying to use AF_ALG to get at ecb(arc4)
>
> (same applies to md4 and ecb(des) btw)
>
> There will always be a long tail of use cases, and at some point, we
> just have to draw the line and remove obsolete and insecure cruft,
> especially when it impedes progress on other fronts.
>

I have ported iwd to Nettle's LGPL 2.1 implementation of ARC4, and the
diffstat is

 src/crypto.c      | 80 ++++++++++++--------
 src/main.c        |  8 --
 unit/test-eapol.c |  3 +-
 3 files changed, 51 insertions(+), 40 deletions(-)

https://git.kernel.org/pub/scm/linux/kernel/git/ardb/iwd.git/log/?h=arc4-cleanup

^ permalink raw reply	[flat|nested] 17+ messages in thread

* Re: [RFC PATCH 4/7] crypto: remove ARC4 support from the skcipher API
  2020-07-02 23:04       ` Ard Biesheuvel
@ 2020-07-18  8:18         ` Ard Biesheuvel
  2020-07-25  7:06           ` Ard Biesheuvel
  0 siblings, 1 reply; 17+ messages in thread
From: Ard Biesheuvel @ 2020-07-18  8:18 UTC (permalink / raw)
  To: Eric Biggers
  Cc: linux-wireless, Marcel Holtmann, Denis Kenzior,
	Linux Kernel Mailing List, Herbert Xu, David S. Miller,
	Greg Kroah-Hartman, Trond Myklebust, Anna Schumaker,
	J. Bruce Fields, Chuck Lever, Linux Crypto Mailing List,
	open list:BPF JIT for MIPS (32-BIT AND 64-BIT),
	devel, linux-nfs

On Fri, 3 Jul 2020 at 02:04, Ard Biesheuvel <ardb@kernel.org> wrote:
>
> On Thu, 2 Jul 2020 at 20:21, Ard Biesheuvel <ardb@kernel.org> wrote:
> >
> > On Thu, 2 Jul 2020 at 19:50, Eric Biggers <ebiggers@kernel.org> wrote:
> > >
> > > [+linux-wireless, Marcel Holtmann, and Denis Kenzior]
> > >
> > > On Thu, Jul 02, 2020 at 12:19:44PM +0200, Ard Biesheuvel wrote:
> > > > Remove the generic ecb(arc4) skcipher, which is slightly cumbersome from
> > > > a maintenance perspective, since it does not quite behave like other
> > > > skciphers do in terms of key vs IV lifetime. Since we are leaving the
> > > > library interface in place, which is used by the various WEP and TKIP
> > > > implementations we have in the tree, we can safely drop this code now
> > > > it no longer has any users.
> > > >
> > > > Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
> > >
> > > Last year there was a discussion where it was mentioned that iwd uses
> > > "ecb(arc4)" via AF_ALG.  So can we really remove it yet?
> > > See https://lkml.kernel.org/r/97BB95F6-4A4C-4984-9EAB-6069E19B4A4F@holtmann.org
> > > Note that the code isn't in "iwd" itself but rather in "libell" which iwd
> > > depends on: https://git.kernel.org/pub/scm/libs/ell/ell.git/
> > >
> > > Apparently it also uses md4 and ecb(des) too.
> > >
> >
> > Ah yes, I remember now :-(
> >
> > > Marcel and Denis, what's your deprecation plan for these obsolete and insecure
> > > algorithms?
> > >
> >
> > Given Denis's statement:
> >
> >   It sounds to me like it was broken and should be fixed.  So our vote /
> >   preference is to have ARC4 fixed to follow the proper semantics.  We
> >   can deal with the kernel behavioral change on our end easily enough;
> >   the required workarounds are the worse evil.
> >
> > I would think that an ABI break is not the end of the world for them,
> > and given how trivial it is to implement RC4 in C, the workaround
> > should be to simply implement RC4 in user space, and not even bother
> > trying to use AF_ALG to get at ecb(arc4)
> >
> > (same applies to md4 and ecb(des) btw)
> >
> > There will always be a long tail of use cases, and at some point, we
> > just have to draw the line and remove obsolete and insecure cruft,
> > especially when it impedes progress on other fronts.
> >
>
> I have ported iwd to Nettle's LGPL 2.1 implementation of ARC4, and the
> diffstat is
>
>  src/crypto.c      | 80 ++++++++++++--------
>  src/main.c        |  8 --
>  unit/test-eapol.c |  3 +-
>  3 files changed, 51 insertions(+), 40 deletions(-)
>
> https://git.kernel.org/pub/scm/linux/kernel/git/ardb/iwd.git/log/?h=arc4-cleanup

Marcel, Denis,

Do you have any objections to the ecb(arc4) skcipher being dropped
from the kernel, given the fallback i proposed above (which is a much
better way of doing rc4 in user space anyway)?

For libell, I would suggest dropping rc4 entirely, once iwd stops
relying on it, as using rc4 for tls is obsolete as well.

^ permalink raw reply	[flat|nested] 17+ messages in thread

* Re: [RFC PATCH 4/7] crypto: remove ARC4 support from the skcipher API
  2020-07-18  8:18         ` Ard Biesheuvel
@ 2020-07-25  7:06           ` Ard Biesheuvel
  2020-08-04 13:59             ` Ard Biesheuvel
  0 siblings, 1 reply; 17+ messages in thread
From: Ard Biesheuvel @ 2020-07-25  7:06 UTC (permalink / raw)
  To: Eric Biggers
  Cc: linux-wireless, Marcel Holtmann, Denis Kenzior,
	Linux Kernel Mailing List, Herbert Xu, David S. Miller,
	Greg Kroah-Hartman, Trond Myklebust, Anna Schumaker,
	J. Bruce Fields, Chuck Lever, Linux Crypto Mailing List,
	open list:BPF JIT for MIPS (32-BIT AND 64-BIT),
	devel, linux-nfs

On Sat, 18 Jul 2020 at 11:18, Ard Biesheuvel <ardb@kernel.org> wrote:
>
> On Fri, 3 Jul 2020 at 02:04, Ard Biesheuvel <ardb@kernel.org> wrote:
> >
> > On Thu, 2 Jul 2020 at 20:21, Ard Biesheuvel <ardb@kernel.org> wrote:
> > >
> > > On Thu, 2 Jul 2020 at 19:50, Eric Biggers <ebiggers@kernel.org> wrote:
> > > >
> > > > [+linux-wireless, Marcel Holtmann, and Denis Kenzior]
> > > >
> > > > On Thu, Jul 02, 2020 at 12:19:44PM +0200, Ard Biesheuvel wrote:
> > > > > Remove the generic ecb(arc4) skcipher, which is slightly cumbersome from
> > > > > a maintenance perspective, since it does not quite behave like other
> > > > > skciphers do in terms of key vs IV lifetime. Since we are leaving the
> > > > > library interface in place, which is used by the various WEP and TKIP
> > > > > implementations we have in the tree, we can safely drop this code now
> > > > > it no longer has any users.
> > > > >
> > > > > Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
> > > >
> > > > Last year there was a discussion where it was mentioned that iwd uses
> > > > "ecb(arc4)" via AF_ALG.  So can we really remove it yet?
> > > > See https://lkml.kernel.org/r/97BB95F6-4A4C-4984-9EAB-6069E19B4A4F@holtmann.org
> > > > Note that the code isn't in "iwd" itself but rather in "libell" which iwd
> > > > depends on: https://git.kernel.org/pub/scm/libs/ell/ell.git/
> > > >
> > > > Apparently it also uses md4 and ecb(des) too.
> > > >
> > >
> > > Ah yes, I remember now :-(
> > >
> > > > Marcel and Denis, what's your deprecation plan for these obsolete and insecure
> > > > algorithms?
> > > >
> > >
> > > Given Denis's statement:
> > >
> > >   It sounds to me like it was broken and should be fixed.  So our vote /
> > >   preference is to have ARC4 fixed to follow the proper semantics.  We
> > >   can deal with the kernel behavioral change on our end easily enough;
> > >   the required workarounds are the worse evil.
> > >
> > > I would think that an ABI break is not the end of the world for them,
> > > and given how trivial it is to implement RC4 in C, the workaround
> > > should be to simply implement RC4 in user space, and not even bother
> > > trying to use AF_ALG to get at ecb(arc4)
> > >
> > > (same applies to md4 and ecb(des) btw)
> > >
> > > There will always be a long tail of use cases, and at some point, we
> > > just have to draw the line and remove obsolete and insecure cruft,
> > > especially when it impedes progress on other fronts.
> > >
> >
> > I have ported iwd to Nettle's LGPL 2.1 implementation of ARC4, and the
> > diffstat is
> >
> >  src/crypto.c      | 80 ++++++++++++--------
> >  src/main.c        |  8 --
> >  unit/test-eapol.c |  3 +-
> >  3 files changed, 51 insertions(+), 40 deletions(-)
> >
> > https://git.kernel.org/pub/scm/linux/kernel/git/ardb/iwd.git/log/?h=arc4-cleanup
>
> Marcel, Denis,
>
> Do you have any objections to the ecb(arc4) skcipher being dropped
> from the kernel, given the fallback i proposed above (which is a much
> better way of doing rc4 in user space anyway)?
>
> For libell, I would suggest dropping rc4 entirely, once iwd stops
> relying on it, as using rc4 for tls is obsolete as well.

Ping?

^ permalink raw reply	[flat|nested] 17+ messages in thread

* Re: [RFC PATCH 4/7] crypto: remove ARC4 support from the skcipher API
  2020-07-25  7:06           ` Ard Biesheuvel
@ 2020-08-04 13:59             ` Ard Biesheuvel
  0 siblings, 0 replies; 17+ messages in thread
From: Ard Biesheuvel @ 2020-08-04 13:59 UTC (permalink / raw)
  To: Eric Biggers, Denis Kenzior, Marcel Holtmann
  Cc: linux-wireless, Linux Kernel Mailing List, Herbert Xu,
	David S. Miller, Greg Kroah-Hartman, Trond Myklebust,
	Anna Schumaker, J. Bruce Fields, Chuck Lever,
	Linux Crypto Mailing List,
	open list:BPF JIT for MIPS (32-BIT AND 64-BIT),
	devel, linux-nfs

On Sat, 25 Jul 2020 at 10:06, Ard Biesheuvel <ardb@kernel.org> wrote:
>
> On Sat, 18 Jul 2020 at 11:18, Ard Biesheuvel <ardb@kernel.org> wrote:
> >
> > On Fri, 3 Jul 2020 at 02:04, Ard Biesheuvel <ardb@kernel.org> wrote:
> > >
> > > On Thu, 2 Jul 2020 at 20:21, Ard Biesheuvel <ardb@kernel.org> wrote:
> > > >
> > > > On Thu, 2 Jul 2020 at 19:50, Eric Biggers <ebiggers@kernel.org> wrote:
> > > > >
> > > > > [+linux-wireless, Marcel Holtmann, and Denis Kenzior]
> > > > >
> > > > > On Thu, Jul 02, 2020 at 12:19:44PM +0200, Ard Biesheuvel wrote:
> > > > > > Remove the generic ecb(arc4) skcipher, which is slightly cumbersome from
> > > > > > a maintenance perspective, since it does not quite behave like other
> > > > > > skciphers do in terms of key vs IV lifetime. Since we are leaving the
> > > > > > library interface in place, which is used by the various WEP and TKIP
> > > > > > implementations we have in the tree, we can safely drop this code now
> > > > > > it no longer has any users.
> > > > > >
> > > > > > Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
> > > > >
> > > > > Last year there was a discussion where it was mentioned that iwd uses
> > > > > "ecb(arc4)" via AF_ALG.  So can we really remove it yet?
> > > > > See https://lkml.kernel.org/r/97BB95F6-4A4C-4984-9EAB-6069E19B4A4F@holtmann.org
> > > > > Note that the code isn't in "iwd" itself but rather in "libell" which iwd
> > > > > depends on: https://git.kernel.org/pub/scm/libs/ell/ell.git/
> > > > >
> > > > > Apparently it also uses md4 and ecb(des) too.
> > > > >
> > > >
> > > > Ah yes, I remember now :-(
> > > >
> > > > > Marcel and Denis, what's your deprecation plan for these obsolete and insecure
> > > > > algorithms?
> > > > >
> > > >
> > > > Given Denis's statement:
> > > >
> > > >   It sounds to me like it was broken and should be fixed.  So our vote /
> > > >   preference is to have ARC4 fixed to follow the proper semantics.  We
> > > >   can deal with the kernel behavioral change on our end easily enough;
> > > >   the required workarounds are the worse evil.
> > > >
> > > > I would think that an ABI break is not the end of the world for them,
> > > > and given how trivial it is to implement RC4 in C, the workaround
> > > > should be to simply implement RC4 in user space, and not even bother
> > > > trying to use AF_ALG to get at ecb(arc4)
> > > >
> > > > (same applies to md4 and ecb(des) btw)
> > > >
> > > > There will always be a long tail of use cases, and at some point, we
> > > > just have to draw the line and remove obsolete and insecure cruft,
> > > > especially when it impedes progress on other fronts.
> > > >
> > >
> > > I have ported iwd to Nettle's LGPL 2.1 implementation of ARC4, and the
> > > diffstat is
> > >
> > >  src/crypto.c      | 80 ++++++++++++--------
> > >  src/main.c        |  8 --
> > >  unit/test-eapol.c |  3 +-
> > >  3 files changed, 51 insertions(+), 40 deletions(-)
> > >
> > > https://git.kernel.org/pub/scm/linux/kernel/git/ardb/iwd.git/log/?h=arc4-cleanup
> >
> > Marcel, Denis,
> >
> > Do you have any objections to the ecb(arc4) skcipher being dropped
> > from the kernel, given the fallback i proposed above (which is a much
> > better way of doing rc4 in user space anyway)?
> >
> > For libell, I would suggest dropping rc4 entirely, once iwd stops
> > relying on it, as using rc4 for tls is obsolete as well.
>
> Ping?

Denis was kind enough to take the changes to iwd and libell that
remove all dependencies on the ecb(arc4) skcipher exposed by the
kernel, so we can at least deprecate it in the short term, and
hopefully remove it entirely at a later stage.

Perhaps we should introduce a Kconfig symbol that needs to be set to
enable deprecated algorithms? That way, we can work with the distros
to phase out the old junk that is piling up, but in a way that doesn't
break people's systems.

^ permalink raw reply	[flat|nested] 17+ messages in thread

end of thread, other threads:[~2020-08-04 14:00 UTC | newest]

Thread overview: 17+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-07-02 10:19 [RFC PATCH 0/7] crypto: get rid of ecb(arc4) Ard Biesheuvel
2020-07-02 10:19 ` [RFC PATCH 1/7] staging/rtl8192e: switch to RC4 library interface Ard Biesheuvel
2020-07-02 10:32   ` Greg Kroah-Hartman
2020-07-02 10:19 ` [RFC PATCH 2/7] staging/rtl8192u: " Ard Biesheuvel
2020-07-02 10:32   ` Greg Kroah-Hartman
2020-07-02 10:19 ` [RFC PATCH 3/7] SUNRPC: remove RC4-HMAC-MD5 support from KerberosV Ard Biesheuvel
2020-07-02 15:49   ` J. Bruce Fields
2020-07-02 10:19 ` [RFC PATCH 4/7] crypto: remove ARC4 support from the skcipher API Ard Biesheuvel
2020-07-02 17:50   ` Eric Biggers
2020-07-02 18:21     ` Ard Biesheuvel
2020-07-02 23:04       ` Ard Biesheuvel
2020-07-18  8:18         ` Ard Biesheuvel
2020-07-25  7:06           ` Ard Biesheuvel
2020-08-04 13:59             ` Ard Biesheuvel
2020-07-02 10:19 ` [RFC PATCH 5/7] crypto: n2 - remove ecb(arc4) support Ard Biesheuvel
2020-07-02 10:19 ` [RFC PATCH 6/7] crypto: bcm-iproc " Ard Biesheuvel
2020-07-02 10:19 ` [RFC PATCH 7/7] crypto: tcrypt - remove ecb(arc4) testing/benchmarking support Ard Biesheuvel

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