[thirdparty/linux.git] / net / ipv6 / seg6_hmac.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  SR-IPv6 implementation -- HMAC functions
 *
 *  Author:
 *  David Lebrun <david.lebrun@uclouvain.be>
 */

#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/net.h>
#include <linux/netdevice.h>
#include <linux/in6.h>
#include <linux/icmpv6.h>
#include <linux/mroute6.h>
#include <linux/slab.h>
#include <linux/rhashtable.h>

#include <linux/netfilter.h>
#include <linux/netfilter_ipv6.h>

#include <net/sock.h>
#include <net/snmp.h>

#include <net/ipv6.h>
#include <net/protocol.h>
#include <net/transp_v6.h>
#include <net/rawv6.h>
#include <net/ndisc.h>
#include <net/ip6_route.h>
#include <net/addrconf.h>
#include <net/xfrm.h>

#include <crypto/hash.h>
#include <crypto/sha.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);

static int seg6_hmac_cmpfn(struct rhashtable_compare_arg *arg, const void *obj)
{
	const struct seg6_hmac_info *hinfo = obj;

	return (hinfo->hmackeyid != *(__u32 *)arg->key);
}

static inline void seg6_hinfo_release(struct seg6_hmac_info *hinfo)
{
	kfree_rcu(hinfo, rcu);
}

static void seg6_free_hi(void *ptr, void *arg)
{
	struct seg6_hmac_info *hinfo = (struct seg6_hmac_info *)ptr;

	if (hinfo)
		seg6_hinfo_release(hinfo);
}

static const struct rhashtable_params rht_params = {
	.head_offset		= offsetof(struct seg6_hmac_info, node),
	.key_offset		= offsetof(struct seg6_hmac_info, hmackeyid),
	.key_len		= sizeof(u32),
	.automatic_shrinking	= true,
	.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;

	if (srh->hdrlen < (srh->first_segment + 1) * 2 + 5)
		return NULL;

	if (!sr_has_hmac(srh))
		return NULL;

	tlv = (struct sr6_tlv_hmac *)
	      ((char *)srh + ((srh->hdrlen + 1) << 3) - 40);

	if (tlv->tlvhdr.type != SR6_TLV_HMAC || tlv->tlvhdr.len != 38)
		return NULL;

	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;
	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;

	/* this limit allows for 14 segments */
	if (plen >= SEG6_HMAC_RING_SIZE)
		return -EMSGSIZE;

	/* Let's build the HMAC text on the ring buffer. The text is composed
	 * as follows, in order:
	 *
	 * 1. Source IPv6 address (128 bits)
	 * 2. first_segment value (8 bits)
	 * 3. Flags (8 bits)
	 * 4. HMAC Key ID (32 bits)
	 * 5. All segments in the segments list (n * 128 bits)
	 */

	local_bh_disable();
	ring = this_cpu_ptr(hmac_ring);
	off = ring;

	/* source address */
	memcpy(off, saddr, 16);
	off += 16;

	/* first_segment value */
	*off++ = hdr->first_segment;

	/* flags */
	*off++ = hdr->flags;

	/* HMAC Key ID */
	memcpy(off, &hmackeyid, 4);
	off += 4;

	/* all segments in the list */
	for (i = 0; i < hdr->first_segment + 1; i++) {
		memcpy(off, hdr->segments + i, 16);
		off += 16;
	}

	dgsize = __do_hmac(hinfo, ring, plen, tmp_out,
			   SEG6_HMAC_MAX_DIGESTSIZE);
	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;
}
EXPORT_SYMBOL(seg6_hmac_compute);

/* checks if an incoming SR-enabled packet's HMAC status matches
 * the incoming policy.
 *
 * called with rcu_read_lock()
 */
bool seg6_hmac_validate_skb(struct sk_buff *skb)
{
	u8 hmac_output[SEG6_HMAC_FIELD_LEN];
	struct net *net = dev_net(skb->dev);
	struct seg6_hmac_info *hinfo;
	struct sr6_tlv_hmac *tlv;
	struct ipv6_sr_hdr *srh;
	struct inet6_dev *idev;

	idev = __in6_dev_get(skb->dev);

	srh = (struct ipv6_sr_hdr *)skb_transport_header(skb);

	tlv = seg6_get_tlv_hmac(srh);

	/* mandatory check but no tlv */
	if (idev->cnf.seg6_require_hmac > 0 && !tlv)
		return false;

	/* no check */
	if (idev->cnf.seg6_require_hmac < 0)
		return true;

	/* check only if present */
	if (idev->cnf.seg6_require_hmac == 0 && !tlv)
		return true;

	/* now, seg6_require_hmac >= 0 && tlv */

	hinfo = seg6_hmac_info_lookup(net, be32_to_cpu(tlv->hmackeyid));
	if (!hinfo)
		return false;

	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)
		return false;

	return true;
}
EXPORT_SYMBOL(seg6_hmac_validate_skb);

/* called with rcu_read_lock() */
struct seg6_hmac_info *seg6_hmac_info_lookup(struct net *net, u32 key)
{
	struct seg6_pernet_data *sdata = seg6_pernet(net);
	struct seg6_hmac_info *hinfo;

	hinfo = rhashtable_lookup_fast(&sdata->hmac_infos, &key, rht_params);

	return hinfo;
}
EXPORT_SYMBOL(seg6_hmac_info_lookup);

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;

	err = rhashtable_lookup_insert_fast(&sdata->hmac_infos, &hinfo->node,
					    rht_params);

	return err;
}
EXPORT_SYMBOL(seg6_hmac_info_add);

int seg6_hmac_info_del(struct net *net, u32 key)
{
	struct seg6_pernet_data *sdata = seg6_pernet(net);
	struct seg6_hmac_info *hinfo;
	int err = -ENOENT;

	hinfo = rhashtable_lookup_fast(&sdata->hmac_infos, &key, rht_params);
	if (!hinfo)
		goto out;

	err = rhashtable_remove_fast(&sdata->hmac_infos, &hinfo->node,
				     rht_params);
	if (err)
		goto out;

	seg6_hinfo_release(hinfo);

out:
	return err;
}
EXPORT_SYMBOL(seg6_hmac_info_del);

int seg6_push_hmac(struct net *net, struct in6_addr *saddr,
		   struct ipv6_sr_hdr *srh)
{
	struct seg6_hmac_info *hinfo;
	struct sr6_tlv_hmac *tlv;
	int err = -ENOENT;

	tlv = seg6_get_tlv_hmac(srh);
	if (!tlv)
		return -EINVAL;

	rcu_read_lock();

	hinfo = seg6_hmac_info_lookup(net, be32_to_cpu(tlv->hmackeyid));
	if (!hinfo)
		goto out;

	memset(tlv->hmac, 0, SEG6_HMAC_FIELD_LEN);
	err = seg6_hmac_compute(hinfo, srh, saddr, tlv->hmac);

out:
	rcu_read_unlock();
	return err;
}
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();
}
EXPORT_SYMBOL(seg6_hmac_init);

int __net_init seg6_hmac_net_init(struct net *net)
{
	struct seg6_pernet_data *sdata = seg6_pernet(net);

	rhashtable_init(&sdata->hmac_infos, &rht_params);

	return 0;
}
EXPORT_SYMBOL(seg6_hmac_net_init);

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);

	rhashtable_free_and_destroy(&sdata->hmac_infos, seg6_free_hi, NULL);
}
EXPORT_SYMBOL(seg6_hmac_net_exit);
Commit	Line	Data
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
bf355b8d DL	2	/*
	3	* SR-IPv6 implementation -- HMAC functions
	4	*
	5	* Author:
	6	* David Lebrun <david.lebrun@uclouvain.be>
bf355b8d DL	7	*/
	8
	9	#include <linux/errno.h>
6391c4f6	10	#include <linux/kernel.h>
bf355b8d DL	11	#include <linux/types.h>
	12	#include <linux/socket.h>
	13	#include <linux/sockios.h>
	14	#include <linux/net.h>
	15	#include <linux/netdevice.h>
	16	#include <linux/in6.h>
	17	#include <linux/icmpv6.h>
	18	#include <linux/mroute6.h>
	19	#include <linux/slab.h>
0eb71a9d	20	#include <linux/rhashtable.h>
bf355b8d DL	21
	22	#include <linux/netfilter.h>
	23	#include <linux/netfilter_ipv6.h>
	24
	25	#include <net/sock.h>
	26	#include <net/snmp.h>
	27
	28	#include <net/ipv6.h>
	29	#include <net/protocol.h>
	30	#include <net/transp_v6.h>
	31	#include <net/rawv6.h>
	32	#include <net/ndisc.h>
	33	#include <net/ip6_route.h>
	34	#include <net/addrconf.h>
	35	#include <net/xfrm.h>
	36
bf355b8d DL	37	#include <crypto/hash.h>
	38	#include <crypto/sha.h>
	39	#include <net/seg6.h>
	40	#include <net/genetlink.h>
	41	#include <net/seg6_hmac.h>
	42	#include <linux/random.h>
	43
717ac5ce	44	static DEFINE_PER_CPU(char [SEG6_HMAC_RING_SIZE], hmac_ring);
bf355b8d DL	45
	46	static int seg6_hmac_cmpfn(struct rhashtable_compare_arg arg, const void obj)
	47	{
	48	const struct seg6_hmac_info *hinfo = obj;
	49
	50	return (hinfo->hmackeyid != (__u32 )arg->key);
	51	}
	52
	53	static inline void seg6_hinfo_release(struct seg6_hmac_info *hinfo)
	54	{
	55	kfree_rcu(hinfo, rcu);
	56	}
	57
	58	static void seg6_free_hi(void ptr, void arg)
	59	{
	60	struct seg6_hmac_info hinfo = (struct seg6_hmac_info )ptr;
	61
	62	if (hinfo)
	63	seg6_hinfo_release(hinfo);
	64	}
	65
	66	static const struct rhashtable_params rht_params = {
	67	.head_offset = offsetof(struct seg6_hmac_info, node),
	68	.key_offset = offsetof(struct seg6_hmac_info, hmackeyid),
	69	.key_len = sizeof(u32),
	70	.automatic_shrinking = true,
	71	.obj_cmpfn = seg6_hmac_cmpfn,
	72	};
	73
	74	static struct seg6_hmac_algo hmac_algos[] = {
	75	{
	76	.alg_id = SEG6_HMAC_ALGO_SHA1,
	77	.name = "hmac(sha1)",
	78	},
	79	{
	80	.alg_id = SEG6_HMAC_ALGO_SHA256,
	81	.name = "hmac(sha256)",
	82	},
	83	};
	84
	85	static struct sr6_tlv_hmac seg6_get_tlv_hmac(struct ipv6_sr_hdr srh)
	86	{
	87	struct sr6_tlv_hmac *tlv;
	88
	89	if (srh->hdrlen < (srh->first_segment + 1) * 2 + 5)
	90	return NULL;
	91
	92	if (!sr_has_hmac(srh))
	93	return NULL;
	94
	95	tlv = (struct sr6_tlv_hmac *)
	96	((char *)srh + ((srh->hdrlen + 1) << 3) - 40);
	97
	98	if (tlv->tlvhdr.type != SR6_TLV_HMAC \|\| tlv->tlvhdr.len != 38)
	99	return NULL;
	100
	101	return tlv;
	102	}
	103
	104	static struct seg6_hmac_algo *__hmac_get_algo(u8 alg_id)
	105	{
	106	struct seg6_hmac_algo *algo;
	107	int i, alg_count;
	108
6391c4f6	109	alg_count = ARRAY_SIZE(hmac_algos);
bf355b8d DL	110	for (i = 0; i < alg_count; i++) {
	111	algo = &hmac_algos[i];
	112	if (algo->alg_id == alg_id)
	113	return algo;
	114	}
	115
	116	return NULL;
	117	}
	118
	119	static int __do_hmac(struct seg6_hmac_info hinfo, const char text, u8 psize,
	120	u8 *output, int outlen)
	121	{
	122	struct seg6_hmac_algo *algo;
	123	struct crypto_shash *tfm;
	124	struct shash_desc *shash;
	125	int ret, dgsize;
	126
	127	algo = __hmac_get_algo(hinfo->alg_id);
	128	if (!algo)
	129	return -ENOENT;
	130
	131	tfm = *this_cpu_ptr(algo->tfms);
	132
	133	dgsize = crypto_shash_digestsize(tfm);
	134	if (dgsize > outlen) {
	135	pr_debug("sr-ipv6: __do_hmac: digest size too big (%d / %d)\n",
	136	dgsize, outlen);
	137	return -ENOMEM;
	138	}
	139
	140	ret = crypto_shash_setkey(tfm, hinfo->secret, hinfo->slen);
	141	if (ret < 0) {
	142	pr_debug("sr-ipv6: crypto_shash_setkey failed: err %d\n", ret);
	143	goto failed;
	144	}
	145
	146	shash = *this_cpu_ptr(algo->shashs);
	147	shash->tfm = tfm;
	148
	149	ret = crypto_shash_digest(shash, text, psize, output);
	150	if (ret < 0) {
	151	pr_debug("sr-ipv6: crypto_shash_digest failed: err %d\n", ret);
	152	goto failed;
	153	}
	154
	155	return dgsize;
	156
	157	failed:
	158	return ret;
	159	}
	160
	161	int seg6_hmac_compute(struct seg6_hmac_info hinfo, struct ipv6_sr_hdr hdr,
	162	struct in6_addr saddr, u8 output)
	163	{
	164	__be32 hmackeyid = cpu_to_be32(hinfo->hmackeyid);
	165	u8 tmp_out[SEG6_HMAC_MAX_DIGESTSIZE];
	166	int plen, i, dgsize, wrsize;
	167	char ring, off;
	168
	169	/* a 160-byte buffer for digest output allows to store highest known
	170	* hash function (RadioGatun) with up to 1216 bits
	171	*/
	172
013e8167	173	/* saddr(16) + first_seg(1) + flags(1) + keyid(4) + seglist(16n) */
bf355b8d DL	174	plen = 16 + 1 + 1 + 4 + (hdr->first_segment + 1) * 16;
	175
	176	/* this limit allows for 14 segments */
	177	if (plen >= SEG6_HMAC_RING_SIZE)
	178	return -EMSGSIZE;
	179
	180	/* Let's build the HMAC text on the ring buffer. The text is composed
	181	* as follows, in order:
	182	*
	183	* 1. Source IPv6 address (128 bits)
	184	* 2. first_segment value (8 bits)
013e8167	185	* 3. Flags (8 bits)
bf355b8d DL	186	* 4. HMAC Key ID (32 bits)
	187	* 5. All segments in the segments list (n * 128 bits)
	188	*/
	189
	190	local_bh_disable();
717ac5ce	191	ring = this_cpu_ptr(hmac_ring);
bf355b8d DL	192	off = ring;
	193
	194	/* source address */
	195	memcpy(off, saddr, 16);
	196	off += 16;
	197
	198	/* first_segment value */
	199	*off++ = hdr->first_segment;
	200
013e8167 DL	201	/* flags */
013e8167 DL	202	*off++ = hdr->flags;
bf355b8d DL	203
	204	/* HMAC Key ID */
	205	memcpy(off, &hmackeyid, 4);
	206	off += 4;
	207
	208	/* all segments in the list */
	209	for (i = 0; i < hdr->first_segment + 1; i++) {
	210	memcpy(off, hdr->segments + i, 16);
	211	off += 16;
	212	}
	213
	214	dgsize = __do_hmac(hinfo, ring, plen, tmp_out,
	215	SEG6_HMAC_MAX_DIGESTSIZE);
	216	local_bh_enable();
	217
	218	if (dgsize < 0)
	219	return dgsize;
	220
	221	wrsize = SEG6_HMAC_FIELD_LEN;
	222	if (wrsize > dgsize)
	223	wrsize = dgsize;
	224
	225	memset(output, 0, SEG6_HMAC_FIELD_LEN);
	226	memcpy(output, tmp_out, wrsize);
	227
	228	return 0;
	229	}
	230	EXPORT_SYMBOL(seg6_hmac_compute);
	231
	232	/* checks if an incoming SR-enabled packet's HMAC status matches
	233	* the incoming policy.
	234	*
	235	* called with rcu_read_lock()
	236	*/
	237	bool seg6_hmac_validate_skb(struct sk_buff *skb)
	238	{
	239	u8 hmac_output[SEG6_HMAC_FIELD_LEN];
	240	struct net *net = dev_net(skb->dev);
	241	struct seg6_hmac_info *hinfo;
	242	struct sr6_tlv_hmac *tlv;
	243	struct ipv6_sr_hdr *srh;
	244	struct inet6_dev *idev;
	245
	246	idev = __in6_dev_get(skb->dev);
	247
	248	srh = (struct ipv6_sr_hdr *)skb_transport_header(skb);
	249
	250	tlv = seg6_get_tlv_hmac(srh);
	251
	252	/* mandatory check but no tlv */
	253	if (idev->cnf.seg6_require_hmac > 0 && !tlv)
	254	return false;
	255
	256	/* no check */
	257	if (idev->cnf.seg6_require_hmac < 0)
	258	return true;
	259
	260	/* check only if present */
	261	if (idev->cnf.seg6_require_hmac == 0 && !tlv)
	262	return true;
	263
	264	/* now, seg6_require_hmac >= 0 && tlv */
	265
	266	hinfo = seg6_hmac_info_lookup(net, be32_to_cpu(tlv->hmackeyid));
267	if (!hinfo)
268	return false;
269
270	if (seg6_hmac_compute(hinfo, srh, &ipv6_hdr(skb)->saddr, hmac_output))
271	return false;
272
273	if (memcmp(hmac_output, tlv->hmac, SEG6_HMAC_FIELD_LEN) != 0)
274	return false;
275
276	return true;
277	}
278	EXPORT_SYMBOL(seg6_hmac_validate_skb);
279
280	/* called with rcu_read_lock() */
281	struct seg6_hmac_info seg6_hmac_info_lookup(struct net net, u32 key)
282	{
283	struct seg6_pernet_data *sdata = seg6_pernet(net);
284	struct seg6_hmac_info *hinfo;
285
286	hinfo = rhashtable_lookup_fast(&sdata->hmac_infos, &key, rht_params);
287
288	return hinfo;
289	}
290	EXPORT_SYMBOL(seg6_hmac_info_lookup);
291
292	int seg6_hmac_info_add(struct net net, u32 key, struct seg6_hmac_info hinfo)
293	{
294	struct seg6_pernet_data *sdata = seg6_pernet(net);
295	int err;
296
297	err = rhashtable_lookup_insert_fast(&sdata->hmac_infos, &hinfo->node,
298	rht_params);
299
300	return err;
301	}
302	EXPORT_SYMBOL(seg6_hmac_info_add);
303
304	int seg6_hmac_info_del(struct net *net, u32 key)
305	{
306	struct seg6_pernet_data *sdata = seg6_pernet(net);
307	struct seg6_hmac_info *hinfo;
308	int err = -ENOENT;
309
310	hinfo = rhashtable_lookup_fast(&sdata->hmac_infos, &key, rht_params);
311	if (!hinfo)
312	goto out;
313
314	err = rhashtable_remove_fast(&sdata->hmac_infos, &hinfo->node,
315	rht_params);
316	if (err)
317	goto out;
318
319	seg6_hinfo_release(hinfo);
320
321	out:
322	return err;
323	}
324	EXPORT_SYMBOL(seg6_hmac_info_del);
325
326	int seg6_push_hmac(struct net net, struct in6_addr saddr,
327	struct ipv6_sr_hdr *srh)
328	{
329	struct seg6_hmac_info *hinfo;
330	struct sr6_tlv_hmac *tlv;
331	int err = -ENOENT;
332
333	tlv = seg6_get_tlv_hmac(srh);
334	if (!tlv)
335	return -EINVAL;
336
337	rcu_read_lock();
338
339	hinfo = seg6_hmac_info_lookup(net, be32_to_cpu(tlv->hmackeyid));
340	if (!hinfo)
341	goto out;
342
343	memset(tlv->hmac, 0, SEG6_HMAC_FIELD_LEN);
344	err = seg6_hmac_compute(hinfo, srh, saddr, tlv->hmac);
345
346	out:
347	rcu_read_unlock();
348	return err;
349	}
350	EXPORT_SYMBOL(seg6_push_hmac);
351
bf355b8d DL	352	static int seg6_hmac_init_algo(void)
	353	{
	354	struct seg6_hmac_algo *algo;
	355	struct crypto_shash *tfm;
	356	struct shash_desc *shash;
	357	int i, alg_count, cpu;
	358
6391c4f6	359	alg_count = ARRAY_SIZE(hmac_algos);
bf355b8d DL	360
	361	for (i = 0; i < alg_count; i++) {
	362	struct crypto_shash **p_tfm;
	363	int shsize;
	364
	365	algo = &hmac_algos[i];
	366	algo->tfms = alloc_percpu(struct crypto_shash *);
	367	if (!algo->tfms)
	368	return -ENOMEM;
	369
	370	for_each_possible_cpu(cpu) {
fc9c2029	371	tfm = crypto_alloc_shash(algo->name, 0, 0);
bf355b8d DL	372	if (IS_ERR(tfm))
	373	return PTR_ERR(tfm);
	374	p_tfm = per_cpu_ptr(algo->tfms, cpu);
	375	*p_tfm = tfm;
	376	}
	377
fa79581e	378	p_tfm = raw_cpu_ptr(algo->tfms);
bf355b8d DL	379	tfm = *p_tfm;
	380
	381	shsize = sizeof(*shash) + crypto_shash_descsize(tfm);
	382
	383	algo->shashs = alloc_percpu(struct shash_desc *);
	384	if (!algo->shashs)
	385	return -ENOMEM;
	386
	387	for_each_possible_cpu(cpu) {
9ca677b1 ED	388	shash = kzalloc_node(shsize, GFP_KERNEL,
9ca677b1 ED	389	cpu_to_node(cpu));
bf355b8d DL	390	if (!shash)
	391	return -ENOMEM;
	392	*per_cpu_ptr(algo->shashs, cpu) = shash;
	393	}
	394	}
	395
	396	return 0;
	397	}
	398
	399	int __init seg6_hmac_init(void)
	400	{
717ac5ce	401	return seg6_hmac_init_algo();
bf355b8d DL	402	}
	403	EXPORT_SYMBOL(seg6_hmac_init);
	404
	405	int __net_init seg6_hmac_net_init(struct net *net)
	406	{
	407	struct seg6_pernet_data *sdata = seg6_pernet(net);
	408
	409	rhashtable_init(&sdata->hmac_infos, &rht_params);
	410
	411	return 0;
	412	}
	413	EXPORT_SYMBOL(seg6_hmac_net_init);
	414
	415	void seg6_hmac_exit(void)
	416	{
	417	struct seg6_hmac_algo *algo = NULL;
	418	int i, alg_count, cpu;
	419
6391c4f6	420	alg_count = ARRAY_SIZE(hmac_algos);
bf355b8d DL	421	for (i = 0; i < alg_count; i++) {
	422	algo = &hmac_algos[i];
	423	for_each_possible_cpu(cpu) {
	424	struct crypto_shash *tfm;
	425	struct shash_desc *shash;
	426
	427	shash = *per_cpu_ptr(algo->shashs, cpu);
	428	kfree(shash);
	429	tfm = *per_cpu_ptr(algo->tfms, cpu);
	430	crypto_free_shash(tfm);
	431	}
	432	free_percpu(algo->tfms);
	433	free_percpu(algo->shashs);
	434	}
	435	}
	436	EXPORT_SYMBOL(seg6_hmac_exit);
	437
	438	void __net_exit seg6_hmac_net_exit(struct net *net)
	439	{
	440	struct seg6_pernet_data *sdata = seg6_pernet(net);
	441
	442	rhashtable_free_and_destroy(&sdata->hmac_infos, seg6_free_hi, NULL);
	443	}
	444	EXPORT_SYMBOL(seg6_hmac_net_exit);