[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/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 <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>
0eb71a9d	25	#include <linux/rhashtable.h>
bf355b8d DL	26
	27	#include <linux/netfilter.h>
	28	#include <linux/netfilter_ipv6.h>
	29
	30	#include <net/sock.h>
	31	#include <net/snmp.h>
	32
	33	#include <net/ipv6.h>
	34	#include <net/protocol.h>
	35	#include <net/transp_v6.h>
	36	#include <net/rawv6.h>
	37	#include <net/ndisc.h>
	38	#include <net/ip6_route.h>
	39	#include <net/addrconf.h>
	40	#include <net/xfrm.h>
	41
	42	#include <linux/cryptohash.h>
	43	#include <crypto/hash.h>
	44	#include <crypto/sha.h>
	45	#include <net/seg6.h>
	46	#include <net/genetlink.h>
	47	#include <net/seg6_hmac.h>
	48	#include <linux/random.h>
	49
717ac5ce	50	static DEFINE_PER_CPU(char [SEG6_HMAC_RING_SIZE], hmac_ring);
bf355b8d DL	51
	52	static int seg6_hmac_cmpfn(struct rhashtable_compare_arg arg, const void obj)
	53	{
	54	const struct seg6_hmac_info *hinfo = obj;
	55
	56	return (hinfo->hmackeyid != (__u32 )arg->key);
	57	}
	58
	59	static inline void seg6_hinfo_release(struct seg6_hmac_info *hinfo)
	60	{
	61	kfree_rcu(hinfo, rcu);
	62	}
	63
	64	static void seg6_free_hi(void ptr, void arg)
	65	{
	66	struct seg6_hmac_info hinfo = (struct seg6_hmac_info )ptr;
	67
	68	if (hinfo)
	69	seg6_hinfo_release(hinfo);
	70	}
	71
	72	static const struct rhashtable_params rht_params = {
	73	.head_offset = offsetof(struct seg6_hmac_info, node),
	74	.key_offset = offsetof(struct seg6_hmac_info, hmackeyid),
	75	.key_len = sizeof(u32),
	76	.automatic_shrinking = true,
	77	.obj_cmpfn = seg6_hmac_cmpfn,
	78	};
	79
	80	static struct seg6_hmac_algo hmac_algos[] = {
	81	{
	82	.alg_id = SEG6_HMAC_ALGO_SHA1,
	83	.name = "hmac(sha1)",
	84	},
	85	{
	86	.alg_id = SEG6_HMAC_ALGO_SHA256,
	87	.name = "hmac(sha256)",
	88	},
	89	};
	90
	91	static struct sr6_tlv_hmac seg6_get_tlv_hmac(struct ipv6_sr_hdr srh)
	92	{
	93	struct sr6_tlv_hmac *tlv;
	94
	95	if (srh->hdrlen < (srh->first_segment + 1) * 2 + 5)
	96	return NULL;
	97
	98	if (!sr_has_hmac(srh))
	99	return NULL;
	100
	101	tlv = (struct sr6_tlv_hmac *)
	102	((char *)srh + ((srh->hdrlen + 1) << 3) - 40);
	103
	104	if (tlv->tlvhdr.type != SR6_TLV_HMAC \|\| tlv->tlvhdr.len != 38)
	105	return NULL;
	106
	107	return tlv;
	108	}
	109
	110	static struct seg6_hmac_algo *__hmac_get_algo(u8 alg_id)
	111	{
	112	struct seg6_hmac_algo *algo;
	113	int i, alg_count;
	114
6391c4f6	115	alg_count = ARRAY_SIZE(hmac_algos);
bf355b8d DL	116	for (i = 0; i < alg_count; i++) {
	117	algo = &hmac_algos[i];
	118	if (algo->alg_id == alg_id)
	119	return algo;
	120	}
	121
	122	return NULL;
	123	}
	124
	125	static int __do_hmac(struct seg6_hmac_info hinfo, const char text, u8 psize,
	126	u8 *output, int outlen)
	127	{
	128	struct seg6_hmac_algo *algo;
	129	struct crypto_shash *tfm;
	130	struct shash_desc *shash;
	131	int ret, dgsize;
	132
	133	algo = __hmac_get_algo(hinfo->alg_id);
	134	if (!algo)
	135	return -ENOENT;
	136
	137	tfm = *this_cpu_ptr(algo->tfms);
	138
	139	dgsize = crypto_shash_digestsize(tfm);
	140	if (dgsize > outlen) {
	141	pr_debug("sr-ipv6: __do_hmac: digest size too big (%d / %d)\n",
	142	dgsize, outlen);
	143	return -ENOMEM;
	144	}
	145
	146	ret = crypto_shash_setkey(tfm, hinfo->secret, hinfo->slen);
	147	if (ret < 0) {
	148	pr_debug("sr-ipv6: crypto_shash_setkey failed: err %d\n", ret);
	149	goto failed;
	150	}
	151
	152	shash = *this_cpu_ptr(algo->shashs);
	153	shash->tfm = tfm;
	154
	155	ret = crypto_shash_digest(shash, text, psize, output);
	156	if (ret < 0) {
	157	pr_debug("sr-ipv6: crypto_shash_digest failed: err %d\n", ret);
	158	goto failed;
	159	}
	160
	161	return dgsize;
	162
	163	failed:
	164	return ret;
	165	}
	166
	167	int seg6_hmac_compute(struct seg6_hmac_info hinfo, struct ipv6_sr_hdr hdr,
	168	struct in6_addr saddr, u8 output)
	169	{
	170	__be32 hmackeyid = cpu_to_be32(hinfo->hmackeyid);
	171	u8 tmp_out[SEG6_HMAC_MAX_DIGESTSIZE];
	172	int plen, i, dgsize, wrsize;
	173	char ring, off;
	174
	175	/* a 160-byte buffer for digest output allows to store highest known
	176	* hash function (RadioGatun) with up to 1216 bits
	177	*/
	178
013e8167	179	/* saddr(16) + first_seg(1) + flags(1) + keyid(4) + seglist(16n) */
bf355b8d DL	180	plen = 16 + 1 + 1 + 4 + (hdr->first_segment + 1) * 16;
	181
	182	/* this limit allows for 14 segments */
	183	if (plen >= SEG6_HMAC_RING_SIZE)
	184	return -EMSGSIZE;
	185
	186	/* Let's build the HMAC text on the ring buffer. The text is composed
	187	* as follows, in order:
	188	*
	189	* 1. Source IPv6 address (128 bits)
	190	* 2. first_segment value (8 bits)
013e8167	191	* 3. Flags (8 bits)
bf355b8d DL	192	* 4. HMAC Key ID (32 bits)
	193	* 5. All segments in the segments list (n * 128 bits)
	194	*/
	195
	196	local_bh_disable();
717ac5ce	197	ring = this_cpu_ptr(hmac_ring);
bf355b8d DL	198	off = ring;
	199
	200	/* source address */
	201	memcpy(off, saddr, 16);
	202	off += 16;
	203
	204	/* first_segment value */
	205	*off++ = hdr->first_segment;
	206
013e8167 DL	207	/* flags */
013e8167 DL	208	*off++ = hdr->flags;
bf355b8d DL	209
	210	/* HMAC Key ID */
	211	memcpy(off, &hmackeyid, 4);
	212	off += 4;
	213
	214	/* all segments in the list */
	215	for (i = 0; i < hdr->first_segment + 1; i++) {
	216	memcpy(off, hdr->segments + i, 16);
	217	off += 16;
	218	}
	219
	220	dgsize = __do_hmac(hinfo, ring, plen, tmp_out,
	221	SEG6_HMAC_MAX_DIGESTSIZE);
	222	local_bh_enable();
	223
	224	if (dgsize < 0)
	225	return dgsize;
	226
	227	wrsize = SEG6_HMAC_FIELD_LEN;
	228	if (wrsize > dgsize)
	229	wrsize = dgsize;
	230
	231	memset(output, 0, SEG6_HMAC_FIELD_LEN);
	232	memcpy(output, tmp_out, wrsize);
	233
	234	return 0;
	235	}
	236	EXPORT_SYMBOL(seg6_hmac_compute);
	237
	238	/* checks if an incoming SR-enabled packet's HMAC status matches
	239	* the incoming policy.
	240	*
	241	* called with rcu_read_lock()
	242	*/
	243	bool seg6_hmac_validate_skb(struct sk_buff *skb)
	244	{
	245	u8 hmac_output[SEG6_HMAC_FIELD_LEN];
	246	struct net *net = dev_net(skb->dev);
	247	struct seg6_hmac_info *hinfo;
	248	struct sr6_tlv_hmac *tlv;
	249	struct ipv6_sr_hdr *srh;
	250	struct inet6_dev *idev;
	251
	252	idev = __in6_dev_get(skb->dev);
	253
	254	srh = (struct ipv6_sr_hdr *)skb_transport_header(skb);
	255
	256	tlv = seg6_get_tlv_hmac(srh);
	257
	258	/* mandatory check but no tlv */
	259	if (idev->cnf.seg6_require_hmac > 0 && !tlv)
	260	return false;
	261
	262	/* no check */
	263	if (idev->cnf.seg6_require_hmac < 0)
	264	return true;
	265
	266	/* check only if present */
	267	if (idev->cnf.seg6_require_hmac == 0 && !tlv)
	268	return true;
	269
	270	/* now, seg6_require_hmac >= 0 && tlv */
	271
	272	hinfo = seg6_hmac_info_lookup(net, be32_to_cpu(tlv->hmackeyid));
273	if (!hinfo)
274	return false;
275
276	if (seg6_hmac_compute(hinfo, srh, &ipv6_hdr(skb)->saddr, hmac_output))
277	return false;
278
279	if (memcmp(hmac_output, tlv->hmac, SEG6_HMAC_FIELD_LEN) != 0)
280	return false;
281
282	return true;
283	}
284	EXPORT_SYMBOL(seg6_hmac_validate_skb);
285
286	/* called with rcu_read_lock() */
287	struct seg6_hmac_info seg6_hmac_info_lookup(struct net net, u32 key)
288	{
289	struct seg6_pernet_data *sdata = seg6_pernet(net);
290	struct seg6_hmac_info *hinfo;
291
292	hinfo = rhashtable_lookup_fast(&sdata->hmac_infos, &key, rht_params);
293
294	return hinfo;
295	}
296	EXPORT_SYMBOL(seg6_hmac_info_lookup);
297
298	int seg6_hmac_info_add(struct net net, u32 key, struct seg6_hmac_info hinfo)
299	{
300	struct seg6_pernet_data *sdata = seg6_pernet(net);
301	int err;
302
303	err = rhashtable_lookup_insert_fast(&sdata->hmac_infos, &hinfo->node,
304	rht_params);
305
306	return err;
307	}
308	EXPORT_SYMBOL(seg6_hmac_info_add);
309
310	int seg6_hmac_info_del(struct net *net, u32 key)
311	{
312	struct seg6_pernet_data *sdata = seg6_pernet(net);
313	struct seg6_hmac_info *hinfo;
314	int err = -ENOENT;
315
316	hinfo = rhashtable_lookup_fast(&sdata->hmac_infos, &key, rht_params);
317	if (!hinfo)
318	goto out;
319
320	err = rhashtable_remove_fast(&sdata->hmac_infos, &hinfo->node,
321	rht_params);
322	if (err)
323	goto out;
324
325	seg6_hinfo_release(hinfo);
326
327	out:
328	return err;
329	}
330	EXPORT_SYMBOL(seg6_hmac_info_del);
331
332	int seg6_push_hmac(struct net net, struct in6_addr saddr,
333	struct ipv6_sr_hdr *srh)
334	{
335	struct seg6_hmac_info *hinfo;
336	struct sr6_tlv_hmac *tlv;
337	int err = -ENOENT;
338
339	tlv = seg6_get_tlv_hmac(srh);
340	if (!tlv)
341	return -EINVAL;
342
343	rcu_read_lock();
344
345	hinfo = seg6_hmac_info_lookup(net, be32_to_cpu(tlv->hmackeyid));
346	if (!hinfo)
347	goto out;
348
349	memset(tlv->hmac, 0, SEG6_HMAC_FIELD_LEN);
350	err = seg6_hmac_compute(hinfo, srh, saddr, tlv->hmac);
351
352	out:
353	rcu_read_unlock();
354	return err;
355	}
356	EXPORT_SYMBOL(seg6_push_hmac);
357
bf355b8d DL	358	static int seg6_hmac_init_algo(void)
	359	{
	360	struct seg6_hmac_algo *algo;
	361	struct crypto_shash *tfm;
	362	struct shash_desc *shash;
	363	int i, alg_count, cpu;
	364
6391c4f6	365	alg_count = ARRAY_SIZE(hmac_algos);
bf355b8d DL	366
	367	for (i = 0; i < alg_count; i++) {
	368	struct crypto_shash **p_tfm;
	369	int shsize;
	370
	371	algo = &hmac_algos[i];
	372	algo->tfms = alloc_percpu(struct crypto_shash *);
	373	if (!algo->tfms)
	374	return -ENOMEM;
	375
	376	for_each_possible_cpu(cpu) {
fc9c2029	377	tfm = crypto_alloc_shash(algo->name, 0, 0);
bf355b8d DL	378	if (IS_ERR(tfm))
	379	return PTR_ERR(tfm);
	380	p_tfm = per_cpu_ptr(algo->tfms, cpu);
	381	*p_tfm = tfm;
	382	}
	383
fa79581e	384	p_tfm = raw_cpu_ptr(algo->tfms);
bf355b8d DL	385	tfm = *p_tfm;
	386
	387	shsize = sizeof(*shash) + crypto_shash_descsize(tfm);
	388
	389	algo->shashs = alloc_percpu(struct shash_desc *);
	390	if (!algo->shashs)
	391	return -ENOMEM;
	392
	393	for_each_possible_cpu(cpu) {
9ca677b1 ED	394	shash = kzalloc_node(shsize, GFP_KERNEL,
9ca677b1 ED	395	cpu_to_node(cpu));
bf355b8d DL	396	if (!shash)
	397	return -ENOMEM;
	398	*per_cpu_ptr(algo->shashs, cpu) = shash;
	399	}
	400	}
	401
	402	return 0;
	403	}
	404
	405	int __init seg6_hmac_init(void)
	406	{
717ac5ce	407	return seg6_hmac_init_algo();
bf355b8d DL	408	}
	409	EXPORT_SYMBOL(seg6_hmac_init);
	410
	411	int __net_init seg6_hmac_net_init(struct net *net)
	412	{
	413	struct seg6_pernet_data *sdata = seg6_pernet(net);
	414
	415	rhashtable_init(&sdata->hmac_infos, &rht_params);
	416
	417	return 0;
	418	}
	419	EXPORT_SYMBOL(seg6_hmac_net_init);
	420
	421	void seg6_hmac_exit(void)
	422	{
	423	struct seg6_hmac_algo *algo = NULL;
	424	int i, alg_count, cpu;
	425
6391c4f6	426	alg_count = ARRAY_SIZE(hmac_algos);
bf355b8d DL	427	for (i = 0; i < alg_count; i++) {
	428	algo = &hmac_algos[i];
	429	for_each_possible_cpu(cpu) {
	430	struct crypto_shash *tfm;
	431	struct shash_desc *shash;
	432
	433	shash = *per_cpu_ptr(algo->shashs, cpu);
	434	kfree(shash);
	435	tfm = *per_cpu_ptr(algo->tfms, cpu);
	436	crypto_free_shash(tfm);
	437	}
	438	free_percpu(algo->tfms);
	439	free_percpu(algo->shashs);
	440	}
	441	}
	442	EXPORT_SYMBOL(seg6_hmac_exit);
	443
	444	void __net_exit seg6_hmac_net_exit(struct net *net)
	445	{
	446	struct seg6_pernet_data *sdata = seg6_pernet(net);
	447
	448	rhashtable_free_and_destroy(&sdata->hmac_infos, seg6_free_hi, NULL);
	449	}
	450	EXPORT_SYMBOL(seg6_hmac_net_exit);