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

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  SR-IPv6 implementation -- HMAC functions
 *
 *  Author:
 *  David Lebrun <[email protected]>
 */

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