1 files changed, 51 insertions, 171 deletions

diff --git a/net/ipv6/seg6_hmac.c b/net/ipv6/seg6_hmac.c
index d43c50a7310d..ee6bac0160ac 100644
--- a/net/ipv6/seg6_hmac.c
+++ b/net/ipv6/seg6_hmac.c
@@ -16,7 +16,6 @@
 #include <linux/in6.h>
 #include <linux/icmpv6.h>
 #include <linux/mroute6.h>
-#include <linux/slab.h>
 #include <linux/rhashtable.h>
 
 #include <linux/netfilter.h>
@@ -34,13 +33,22 @@
 #include <net/addrconf.h>
 #include <net/xfrm.h>
 
-#include <crypto/hash.h>
+#include <crypto/sha1.h>
+#include <crypto/sha2.h>
+#include <crypto/utils.h>
 #include <net/seg6.h>
 #include <net/genetlink.h>
 #include <net/seg6_hmac.h>
 #include <linux/random.h>
 
-static DEFINE_PER_CPU(char [SEG6_HMAC_RING_SIZE], hmac_ring);
+struct hmac_storage {
+	local_lock_t bh_lock;
+	char hmac_ring[SEG6_HMAC_RING_SIZE];
+};
+
+static DEFINE_PER_CPU(struct hmac_storage, hmac_storage) = {
+	.bh_lock = INIT_LOCAL_LOCK(bh_lock),
+};
 
 static int seg6_hmac_cmpfn(struct rhashtable_compare_arg *arg, const void *obj)
 {
@@ -70,17 +78,6 @@ static const struct rhashtable_params rht_params = {
 	.obj_cmpfn		= seg6_hmac_cmpfn,
 };
 
-static struct seg6_hmac_algo hmac_algos[] = {
-	{
-		.alg_id = SEG6_HMAC_ALGO_SHA1,
-		.name = "hmac(sha1)",
-	},
-	{
-		.alg_id = SEG6_HMAC_ALGO_SHA256,
-		.name = "hmac(sha256)",
-	},
-};
-
 static struct sr6_tlv_hmac *seg6_get_tlv_hmac(struct ipv6_sr_hdr *srh)
 {
 	struct sr6_tlv_hmac *tlv;
@@ -100,75 +97,13 @@ static struct sr6_tlv_hmac *seg6_get_tlv_hmac(struct ipv6_sr_hdr *srh)
 	return tlv;
 }
 
-static struct seg6_hmac_algo *__hmac_get_algo(u8 alg_id)
-{
-	struct seg6_hmac_algo *algo;
-	int i, alg_count;
-
-	alg_count = ARRAY_SIZE(hmac_algos);
-	for (i = 0; i < alg_count; i++) {
-		algo = &hmac_algos[i];
-		if (algo->alg_id == alg_id)
-			return algo;
-	}
-
-	return NULL;
-}
-
-static int __do_hmac(struct seg6_hmac_info *hinfo, const char *text, u8 psize,
-		     u8 *output, int outlen)
-{
-	struct seg6_hmac_algo *algo;
-	struct crypto_shash *tfm;
-	struct shash_desc *shash;
-	int ret, dgsize;
-
-	algo = __hmac_get_algo(hinfo->alg_id);
-	if (!algo)
-		return -ENOENT;
-
-	tfm = *this_cpu_ptr(algo->tfms);
-
-	dgsize = crypto_shash_digestsize(tfm);
-	if (dgsize > outlen) {
-		pr_debug("sr-ipv6: __do_hmac: digest size too big (%d / %d)\n",
-			 dgsize, outlen);
-		return -ENOMEM;
-	}
-
-	ret = crypto_shash_setkey(tfm, hinfo->secret, hinfo->slen);
-	if (ret < 0) {
-		pr_debug("sr-ipv6: crypto_shash_setkey failed: err %d\n", ret);
-		goto failed;
-	}
-
-	shash = *this_cpu_ptr(algo->shashs);
-	shash->tfm = tfm;
-
-	ret = crypto_shash_digest(shash, text, psize, output);
-	if (ret < 0) {
-		pr_debug("sr-ipv6: crypto_shash_digest failed: err %d\n", ret);
-		goto failed;
-	}
-
-	return dgsize;
-
-failed:
-	return ret;
-}
-
 int seg6_hmac_compute(struct seg6_hmac_info *hinfo, struct ipv6_sr_hdr *hdr,
 		      struct in6_addr *saddr, u8 *output)
 {
 	__be32 hmackeyid = cpu_to_be32(hinfo->hmackeyid);
-	u8 tmp_out[SEG6_HMAC_MAX_DIGESTSIZE];
-	int plen, i, dgsize, wrsize;
+	int plen, i, ret = 0;
 	char *ring, *off;
 
-	/* a 160-byte buffer for digest output allows to store highest known
-	 * hash function (RadioGatun) with up to 1216 bits
-	 */
-
 	/* saddr(16) + first_seg(1) + flags(1) + keyid(4) + seglist(16n) */
 	plen = 16 + 1 + 1 + 4 + (hdr->first_segment + 1) * 16;
 
@@ -187,7 +122,8 @@ int seg6_hmac_compute(struct seg6_hmac_info *hinfo, struct ipv6_sr_hdr *hdr,
 	 */
 
 	local_bh_disable();
-	ring = this_cpu_ptr(hmac_ring);
+	local_lock_nested_bh(&hmac_storage.bh_lock);
+	ring = this_cpu_ptr(hmac_storage.hmac_ring);
 	off = ring;
 
 	/* source address */
@@ -210,21 +146,25 @@ int seg6_hmac_compute(struct seg6_hmac_info *hinfo, struct ipv6_sr_hdr *hdr,
 		off += 16;
 	}
 
-	dgsize = __do_hmac(hinfo, ring, plen, tmp_out,
-			   SEG6_HMAC_MAX_DIGESTSIZE);
+	switch (hinfo->alg_id) {
+	case SEG6_HMAC_ALGO_SHA1:
+		hmac_sha1(&hinfo->key.sha1, ring, plen, output);
+		static_assert(SEG6_HMAC_FIELD_LEN > SHA1_DIGEST_SIZE);
+		memset(&output[SHA1_DIGEST_SIZE], 0,
+		       SEG6_HMAC_FIELD_LEN - SHA1_DIGEST_SIZE);
+		break;
+	case SEG6_HMAC_ALGO_SHA256:
+		hmac_sha256(&hinfo->key.sha256, ring, plen, output);
+		static_assert(SEG6_HMAC_FIELD_LEN == SHA256_DIGEST_SIZE);
+		break;
+	default:
+		WARN_ON_ONCE(1);
+		ret = -EINVAL;
+		break;
+	}
+	local_unlock_nested_bh(&hmac_storage.bh_lock);
 	local_bh_enable();
-
-	if (dgsize < 0)
-		return dgsize;
-
-	wrsize = SEG6_HMAC_FIELD_LEN;
-	if (wrsize > dgsize)
-		wrsize = dgsize;
-
-	memset(output, 0, SEG6_HMAC_FIELD_LEN);
-	memcpy(output, tmp_out, wrsize);
-
-	return 0;
+	return ret;
 }
 EXPORT_SYMBOL(seg6_hmac_compute);
 
@@ -241,6 +181,7 @@ bool seg6_hmac_validate_skb(struct sk_buff *skb)
 	struct sr6_tlv_hmac *tlv;
 	struct ipv6_sr_hdr *srh;
 	struct inet6_dev *idev;
+	int require_hmac;
 
 	idev = __in6_dev_get(skb->dev);
 
@@ -248,16 +189,17 @@ bool seg6_hmac_validate_skb(struct sk_buff *skb)
 
 	tlv = seg6_get_tlv_hmac(srh);
 
+	require_hmac = READ_ONCE(idev->cnf.seg6_require_hmac);
 	/* mandatory check but no tlv */
-	if (idev->cnf.seg6_require_hmac > 0 && !tlv)
+	if (require_hmac > 0 && !tlv)
 		return false;
 
 	/* no check */
-	if (idev->cnf.seg6_require_hmac < 0)
+	if (require_hmac < 0)
 		return true;
 
 	/* check only if present */
-	if (idev->cnf.seg6_require_hmac == 0 && !tlv)
+	if (require_hmac == 0 && !tlv)
 		return true;
 
 	/* now, seg6_require_hmac >= 0 && tlv */
@@ -269,7 +211,7 @@ bool seg6_hmac_validate_skb(struct sk_buff *skb)
 	if (seg6_hmac_compute(hinfo, srh, &ipv6_hdr(skb)->saddr, hmac_output))
 		return false;
 
-	if (memcmp(hmac_output, tlv->hmac, SEG6_HMAC_FIELD_LEN) != 0)
+	if (crypto_memneq(hmac_output, tlv->hmac, SEG6_HMAC_FIELD_LEN))
 		return false;
 
 	return true;
@@ -293,6 +235,19 @@ int seg6_hmac_info_add(struct net *net, u32 key, struct seg6_hmac_info *hinfo)
 	struct seg6_pernet_data *sdata = seg6_pernet(net);
 	int err;
 
+	switch (hinfo->alg_id) {
+	case SEG6_HMAC_ALGO_SHA1:
+		hmac_sha1_preparekey(&hinfo->key.sha1,
+				     hinfo->secret, hinfo->slen);
+		break;
+	case SEG6_HMAC_ALGO_SHA256:
+		hmac_sha256_preparekey(&hinfo->key.sha256,
+				       hinfo->secret, hinfo->slen);
+		break;
+	default:
+		return -EINVAL;
+	}
+
 	err = rhashtable_lookup_insert_fast(&sdata->hmac_infos, &hinfo->node,
 					    rht_params);
 
@@ -348,58 +303,6 @@ out:
 }
 EXPORT_SYMBOL(seg6_push_hmac);
 
-static int seg6_hmac_init_algo(void)
-{
-	struct seg6_hmac_algo *algo;
-	struct crypto_shash *tfm;
-	struct shash_desc *shash;
-	int i, alg_count, cpu;
-
-	alg_count = ARRAY_SIZE(hmac_algos);
-
-	for (i = 0; i < alg_count; i++) {
-		struct crypto_shash **p_tfm;
-		int shsize;
-
-		algo = &hmac_algos[i];
-		algo->tfms = alloc_percpu(struct crypto_shash *);
-		if (!algo->tfms)
-			return -ENOMEM;
-
-		for_each_possible_cpu(cpu) {
-			tfm = crypto_alloc_shash(algo->name, 0, 0);
-			if (IS_ERR(tfm))
-				return PTR_ERR(tfm);
-			p_tfm = per_cpu_ptr(algo->tfms, cpu);
-			*p_tfm = tfm;
-		}
-
-		p_tfm = raw_cpu_ptr(algo->tfms);
-		tfm = *p_tfm;
-
-		shsize = sizeof(*shash) + crypto_shash_descsize(tfm);
-
-		algo->shashs = alloc_percpu(struct shash_desc *);
-		if (!algo->shashs)
-			return -ENOMEM;
-
-		for_each_possible_cpu(cpu) {
-			shash = kzalloc_node(shsize, GFP_KERNEL,
-					     cpu_to_node(cpu));
-			if (!shash)
-				return -ENOMEM;
-			*per_cpu_ptr(algo->shashs, cpu) = shash;
-		}
-	}
-
-	return 0;
-}
-
-int __init seg6_hmac_init(void)
-{
-	return seg6_hmac_init_algo();
-}
-
 int __net_init seg6_hmac_net_init(struct net *net)
 {
 	struct seg6_pernet_data *sdata = seg6_pernet(net);
@@ -407,29 +310,6 @@ int __net_init seg6_hmac_net_init(struct net *net)
 	return rhashtable_init(&sdata->hmac_infos, &rht_params);
 }
 
-void seg6_hmac_exit(void)
-{
-	struct seg6_hmac_algo *algo = NULL;
-	int i, alg_count, cpu;
-
-	alg_count = ARRAY_SIZE(hmac_algos);
-	for (i = 0; i < alg_count; i++) {
-		algo = &hmac_algos[i];
-		for_each_possible_cpu(cpu) {
-			struct crypto_shash *tfm;
-			struct shash_desc *shash;
-
-			shash = *per_cpu_ptr(algo->shashs, cpu);
-			kfree(shash);
-			tfm = *per_cpu_ptr(algo->tfms, cpu);
-			crypto_free_shash(tfm);
-		}
-		free_percpu(algo->tfms);
-		free_percpu(algo->shashs);
-	}
-}
-EXPORT_SYMBOL(seg6_hmac_exit);
-
 void __net_exit seg6_hmac_net_exit(struct net *net)
 {
 	struct seg6_pernet_data *sdata = seg6_pernet(net);