[linux-2.6-block.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/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 = sizeof(hmac_algos) / sizeof(struct seg6_hmac_algo);
	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 = sizeof(hmac_algos) / sizeof(struct seg6_hmac_algo);

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