[mirror_ubuntu-bionic-kernel.git] / net / ipv6 / seg6_hmac.c

/*
 *  SR-IPv6 implementation -- HMAC functions
 *
 *  Author:
 *  David Lebrun <david.lebrun@uclouvain.be>
 *
 *
 *  This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 */

#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/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 <linux/cryptohash.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
bf355b8d DL	1	/*
	2	* SR-IPv6 implementation -- HMAC functions
	3	*
	4	* Author:
	5	* David Lebrun <david.lebrun@uclouvain.be>
	6	*
	7	*
	8	* This program is free software; you can redistribute it and/or
	9	* modify it under the terms of the GNU General Public License
	10	* as published by the Free Software Foundation; either version
	11	* 2 of the License, or (at your option) any later version.
	12	*/
	13
	14	#include <linux/errno.h>
6391c4f6	15	#include <linux/kernel.h>
bf355b8d DL	16	#include <linux/types.h>
	17	#include <linux/socket.h>
	18	#include <linux/sockios.h>
	19	#include <linux/net.h>
	20	#include <linux/netdevice.h>
	21	#include <linux/in6.h>
	22	#include <linux/icmpv6.h>
	23	#include <linux/mroute6.h>
	24	#include <linux/slab.h>
	25
	26	#include <linux/netfilter.h>
	27	#include <linux/netfilter_ipv6.h>
	28
	29	#include <net/sock.h>
	30	#include <net/snmp.h>
	31
	32	#include <net/ipv6.h>
	33	#include <net/protocol.h>
	34	#include <net/transp_v6.h>
	35	#include <net/rawv6.h>
	36	#include <net/ndisc.h>
	37	#include <net/ip6_route.h>
	38	#include <net/addrconf.h>
	39	#include <net/xfrm.h>
	40
	41	#include <linux/cryptohash.h>
	42	#include <crypto/hash.h>
	43	#include <crypto/sha.h>
	44	#include <net/seg6.h>
	45	#include <net/genetlink.h>
	46	#include <net/seg6_hmac.h>
	47	#include <linux/random.h>
	48
717ac5ce	49	static DEFINE_PER_CPU(char [SEG6_HMAC_RING_SIZE], hmac_ring);
bf355b8d DL	50
	51	static int seg6_hmac_cmpfn(struct rhashtable_compare_arg arg, const void obj)
	52	{
	53	const struct seg6_hmac_info *hinfo = obj;
	54
	55	return (hinfo->hmackeyid != (__u32 )arg->key);
	56	}
	57
	58	static inline void seg6_hinfo_release(struct seg6_hmac_info *hinfo)
	59	{
	60	kfree_rcu(hinfo, rcu);
	61	}
	62
	63	static void seg6_free_hi(void ptr, void arg)
	64	{
	65	struct seg6_hmac_info hinfo = (struct seg6_hmac_info )ptr;
	66
	67	if (hinfo)
	68	seg6_hinfo_release(hinfo);
	69	}
	70
	71	static const struct rhashtable_params rht_params = {
	72	.head_offset = offsetof(struct seg6_hmac_info, node),
	73	.key_offset = offsetof(struct seg6_hmac_info, hmackeyid),
	74	.key_len = sizeof(u32),
	75	.automatic_shrinking = true,
	76	.obj_cmpfn = seg6_hmac_cmpfn,
	77	};
	78
	79	static struct seg6_hmac_algo hmac_algos[] = {
	80	{
	81	.alg_id = SEG6_HMAC_ALGO_SHA1,
	82	.name = "hmac(sha1)",
	83	},
	84	{
	85	.alg_id = SEG6_HMAC_ALGO_SHA256,
	86	.name = "hmac(sha256)",
	87	},
	88	};
	89
	90	static struct sr6_tlv_hmac seg6_get_tlv_hmac(struct ipv6_sr_hdr srh)
	91	{
	92	struct sr6_tlv_hmac *tlv;
	93
	94	if (srh->hdrlen < (srh->first_segment + 1) * 2 + 5)
	95	return NULL;
	96
	97	if (!sr_has_hmac(srh))
	98	return NULL;
	99
	100	tlv = (struct sr6_tlv_hmac *)
	101	((char *)srh + ((srh->hdrlen + 1) << 3) - 40);
	102
	103	if (tlv->tlvhdr.type != SR6_TLV_HMAC \|\| tlv->tlvhdr.len != 38)
	104	return NULL;
	105
	106	return tlv;
	107	}
	108
	109	static struct seg6_hmac_algo *__hmac_get_algo(u8 alg_id)
	110	{
	111	struct seg6_hmac_algo *algo;
	112	int i, alg_count;
	113
6391c4f6	114	alg_count = ARRAY_SIZE(hmac_algos);
bf355b8d DL	115	for (i = 0; i < alg_count; i++) {
	116	algo = &hmac_algos[i];
	117	if (algo->alg_id == alg_id)
	118	return algo;
	119	}
	120
	121	return NULL;
	122	}
	123
	124	static int __do_hmac(struct seg6_hmac_info hinfo, const char text, u8 psize,
	125	u8 *output, int outlen)
	126	{
	127	struct seg6_hmac_algo *algo;
	128	struct crypto_shash *tfm;
	129	struct shash_desc *shash;
	130	int ret, dgsize;
	131
	132	algo = __hmac_get_algo(hinfo->alg_id);
	133	if (!algo)
	134	return -ENOENT;
	135
	136	tfm = *this_cpu_ptr(algo->tfms);
	137
	138	dgsize = crypto_shash_digestsize(tfm);
	139	if (dgsize > outlen) {
	140	pr_debug("sr-ipv6: __do_hmac: digest size too big (%d / %d)\n",
	141	dgsize, outlen);
	142	return -ENOMEM;
	143	}
	144
	145	ret = crypto_shash_setkey(tfm, hinfo->secret, hinfo->slen);
	146	if (ret < 0) {
	147	pr_debug("sr-ipv6: crypto_shash_setkey failed: err %d\n", ret);
	148	goto failed;
	149	}
	150
	151	shash = *this_cpu_ptr(algo->shashs);
	152	shash->tfm = tfm;
	153
	154	ret = crypto_shash_digest(shash, text, psize, output);
	155	if (ret < 0) {
	156	pr_debug("sr-ipv6: crypto_shash_digest failed: err %d\n", ret);
	157	goto failed;
	158	}
	159
	160	return dgsize;
	161
	162	failed:
	163	return ret;
	164	}
	165
	166	int seg6_hmac_compute(struct seg6_hmac_info hinfo, struct ipv6_sr_hdr hdr,
	167	struct in6_addr saddr, u8 output)
	168	{
	169	__be32 hmackeyid = cpu_to_be32(hinfo->hmackeyid);
	170	u8 tmp_out[SEG6_HMAC_MAX_DIGESTSIZE];
	171	int plen, i, dgsize, wrsize;
	172	char ring, off;
	173
	174	/* a 160-byte buffer for digest output allows to store highest known
	175	* hash function (RadioGatun) with up to 1216 bits
	176	*/
	177
013e8167	178	/* saddr(16) + first_seg(1) + flags(1) + keyid(4) + seglist(16n) */
bf355b8d DL	179	plen = 16 + 1 + 1 + 4 + (hdr->first_segment + 1) * 16;
	180
	181	/* this limit allows for 14 segments */
	182	if (plen >= SEG6_HMAC_RING_SIZE)
	183	return -EMSGSIZE;
	184
	185	/* Let's build the HMAC text on the ring buffer. The text is composed
	186	* as follows, in order:
	187	*
	188	* 1. Source IPv6 address (128 bits)
	189	* 2. first_segment value (8 bits)
013e8167	190	* 3. Flags (8 bits)
bf355b8d DL	191	* 4. HMAC Key ID (32 bits)
	192	* 5. All segments in the segments list (n * 128 bits)
	193	*/
	194
	195	local_bh_disable();
717ac5ce	196	ring = this_cpu_ptr(hmac_ring);
bf355b8d DL	197	off = ring;
	198
	199	/* source address */
	200	memcpy(off, saddr, 16);
	201	off += 16;
	202
	203	/* first_segment value */
	204	*off++ = hdr->first_segment;
	205
013e8167 DL	206	/* flags */
013e8167 DL	207	*off++ = hdr->flags;
bf355b8d DL	208
	209	/* HMAC Key ID */
	210	memcpy(off, &hmackeyid, 4);
	211	off += 4;
	212
	213	/* all segments in the list */
	214	for (i = 0; i < hdr->first_segment + 1; i++) {
	215	memcpy(off, hdr->segments + i, 16);
	216	off += 16;
	217	}
	218
	219	dgsize = __do_hmac(hinfo, ring, plen, tmp_out,
	220	SEG6_HMAC_MAX_DIGESTSIZE);
	221	local_bh_enable();
	222
	223	if (dgsize < 0)
	224	return dgsize;
	225
	226	wrsize = SEG6_HMAC_FIELD_LEN;
	227	if (wrsize > dgsize)
	228	wrsize = dgsize;
	229
	230	memset(output, 0, SEG6_HMAC_FIELD_LEN);
	231	memcpy(output, tmp_out, wrsize);
	232
	233	return 0;
	234	}
	235	EXPORT_SYMBOL(seg6_hmac_compute);
	236
	237	/* checks if an incoming SR-enabled packet's HMAC status matches
	238	* the incoming policy.
	239	*
	240	* called with rcu_read_lock()
	241	*/
	242	bool seg6_hmac_validate_skb(struct sk_buff *skb)
	243	{
	244	u8 hmac_output[SEG6_HMAC_FIELD_LEN];
	245	struct net *net = dev_net(skb->dev);
	246	struct seg6_hmac_info *hinfo;
	247	struct sr6_tlv_hmac *tlv;
	248	struct ipv6_sr_hdr *srh;
	249	struct inet6_dev *idev;
	250
	251	idev = __in6_dev_get(skb->dev);
	252
	253	srh = (struct ipv6_sr_hdr *)skb_transport_header(skb);
	254
	255	tlv = seg6_get_tlv_hmac(srh);
	256
	257	/* mandatory check but no tlv */
	258	if (idev->cnf.seg6_require_hmac > 0 && !tlv)
	259	return false;
	260
	261	/* no check */
	262	if (idev->cnf.seg6_require_hmac < 0)
	263	return true;
	264
	265	/* check only if present */
	266	if (idev->cnf.seg6_require_hmac == 0 && !tlv)
	267	return true;
	268
	269	/* now, seg6_require_hmac >= 0 && tlv */
	270
	271	hinfo = seg6_hmac_info_lookup(net, be32_to_cpu(tlv->hmackeyid));
272	if (!hinfo)
273	return false;
274
275	if (seg6_hmac_compute(hinfo, srh, &ipv6_hdr(skb)->saddr, hmac_output))
276	return false;
277
278	if (memcmp(hmac_output, tlv->hmac, SEG6_HMAC_FIELD_LEN) != 0)
279	return false;
280
281	return true;
282	}
283	EXPORT_SYMBOL(seg6_hmac_validate_skb);
284
285	/* called with rcu_read_lock() */
286	struct seg6_hmac_info seg6_hmac_info_lookup(struct net net, u32 key)
287	{
288	struct seg6_pernet_data *sdata = seg6_pernet(net);
289	struct seg6_hmac_info *hinfo;
290
291	hinfo = rhashtable_lookup_fast(&sdata->hmac_infos, &key, rht_params);
292
293	return hinfo;
294	}
295	EXPORT_SYMBOL(seg6_hmac_info_lookup);
296
297	int seg6_hmac_info_add(struct net net, u32 key, struct seg6_hmac_info hinfo)
298	{
299	struct seg6_pernet_data *sdata = seg6_pernet(net);
300	int err;
301
302	err = rhashtable_lookup_insert_fast(&sdata->hmac_infos, &hinfo->node,
303	rht_params);
304
305	return err;
306	}
307	EXPORT_SYMBOL(seg6_hmac_info_add);
308
309	int seg6_hmac_info_del(struct net *net, u32 key)
310	{
311	struct seg6_pernet_data *sdata = seg6_pernet(net);
312	struct seg6_hmac_info *hinfo;
313	int err = -ENOENT;
314
315	hinfo = rhashtable_lookup_fast(&sdata->hmac_infos, &key, rht_params);
316	if (!hinfo)
317	goto out;
318
319	err = rhashtable_remove_fast(&sdata->hmac_infos, &hinfo->node,
320	rht_params);
321	if (err)
322	goto out;
323
324	seg6_hinfo_release(hinfo);
325
326	out:
327	return err;
328	}
329	EXPORT_SYMBOL(seg6_hmac_info_del);
330
331	int seg6_push_hmac(struct net net, struct in6_addr saddr,
332	struct ipv6_sr_hdr *srh)
333	{
334	struct seg6_hmac_info *hinfo;
335	struct sr6_tlv_hmac *tlv;
336	int err = -ENOENT;
337
338	tlv = seg6_get_tlv_hmac(srh);
339	if (!tlv)
340	return -EINVAL;
341
342	rcu_read_lock();
343
344	hinfo = seg6_hmac_info_lookup(net, be32_to_cpu(tlv->hmackeyid));
345	if (!hinfo)
346	goto out;
347
348	memset(tlv->hmac, 0, SEG6_HMAC_FIELD_LEN);
349	err = seg6_hmac_compute(hinfo, srh, saddr, tlv->hmac);
350
351	out:
352	rcu_read_unlock();
353	return err;
354	}
355	EXPORT_SYMBOL(seg6_push_hmac);
356
bf355b8d DL	357	static int seg6_hmac_init_algo(void)
	358	{
	359	struct seg6_hmac_algo *algo;
	360	struct crypto_shash *tfm;
	361	struct shash_desc *shash;
	362	int i, alg_count, cpu;
	363
6391c4f6	364	alg_count = ARRAY_SIZE(hmac_algos);
bf355b8d DL	365
	366	for (i = 0; i < alg_count; i++) {
	367	struct crypto_shash **p_tfm;
	368	int shsize;
	369
	370	algo = &hmac_algos[i];
	371	algo->tfms = alloc_percpu(struct crypto_shash *);
	372	if (!algo->tfms)
	373	return -ENOMEM;
	374
	375	for_each_possible_cpu(cpu) {
f7c67396	376	tfm = crypto_alloc_shash(algo->name, 0, 0);
bf355b8d DL	377	if (IS_ERR(tfm))
	378	return PTR_ERR(tfm);
	379	p_tfm = per_cpu_ptr(algo->tfms, cpu);
	380	*p_tfm = tfm;
	381	}
	382
fa79581e	383	p_tfm = raw_cpu_ptr(algo->tfms);
bf355b8d DL	384	tfm = *p_tfm;
	385
	386	shsize = sizeof(*shash) + crypto_shash_descsize(tfm);
	387
	388	algo->shashs = alloc_percpu(struct shash_desc *);
	389	if (!algo->shashs)
	390	return -ENOMEM;
	391
	392	for_each_possible_cpu(cpu) {
9ca677b1 ED	393	shash = kzalloc_node(shsize, GFP_KERNEL,
9ca677b1 ED	394	cpu_to_node(cpu));
bf355b8d DL	395	if (!shash)
	396	return -ENOMEM;
	397	*per_cpu_ptr(algo->shashs, cpu) = shash;
	398	}
	399	}
	400
	401	return 0;
	402	}
	403
	404	int __init seg6_hmac_init(void)
	405	{
717ac5ce	406	return seg6_hmac_init_algo();
bf355b8d DL	407	}
	408	EXPORT_SYMBOL(seg6_hmac_init);
	409
	410	int __net_init seg6_hmac_net_init(struct net *net)
	411	{
	412	struct seg6_pernet_data *sdata = seg6_pernet(net);
	413
	414	rhashtable_init(&sdata->hmac_infos, &rht_params);
	415
	416	return 0;
	417	}
	418	EXPORT_SYMBOL(seg6_hmac_net_init);
	419
	420	void seg6_hmac_exit(void)
	421	{
	422	struct seg6_hmac_algo *algo = NULL;
	423	int i, alg_count, cpu;
	424
6391c4f6	425	alg_count = ARRAY_SIZE(hmac_algos);
bf355b8d DL	426	for (i = 0; i < alg_count; i++) {
	427	algo = &hmac_algos[i];
	428	for_each_possible_cpu(cpu) {
	429	struct crypto_shash *tfm;
	430	struct shash_desc *shash;
	431
	432	shash = *per_cpu_ptr(algo->shashs, cpu);
	433	kfree(shash);
	434	tfm = *per_cpu_ptr(algo->tfms, cpu);
	435	crypto_free_shash(tfm);
	436	}
	437	free_percpu(algo->tfms);
	438	free_percpu(algo->shashs);
	439	}
	440	}
	441	EXPORT_SYMBOL(seg6_hmac_exit);
	442
	443	void __net_exit seg6_hmac_net_exit(struct net *net)
	444	{
	445	struct seg6_pernet_data *sdata = seg6_pernet(net);
	446
	447	rhashtable_free_and_destroy(&sdata->hmac_infos, seg6_free_hi, NULL);
	448	}
	449	EXPORT_SYMBOL(seg6_hmac_net_exit);