diff --git a/usrsctplib/netinet/sctp_auth.h b/usrsctplib/netinet/sctp_auth.h
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+++ b/usrsctplib/netinet/sctp_auth.h
@@ -0,0 +1,216 @@
+/*-
+ * Copyright (c) 2001-2008, by Cisco Systems, Inc. All rights reserved.
+ * Copyright (c) 2008-2012, by Randall Stewart. All rights reserved.
+ * Copyright (c) 2008-2012, by Michael Tuexen. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * a) Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ *
+ * b) Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the distribution.
+ *
+ * c) Neither the name of Cisco Systems, Inc. nor the names of its
+ *    contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+ * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+ * THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifdef __FreeBSD__
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD: head/sys/netinet/sctp_auth.h 310590 2016-12-26 11:06:41Z tuexen $");
+#endif
+
+#ifndef _NETINET_SCTP_AUTH_H_
+#define _NETINET_SCTP_AUTH_H_
+
+#include <netinet/sctp_os.h>
+
+/* digest lengths */
+#define SCTP_AUTH_DIGEST_LEN_SHA1	20
+#define SCTP_AUTH_DIGEST_LEN_SHA256	32
+#define SCTP_AUTH_DIGEST_LEN_MAX	SCTP_AUTH_DIGEST_LEN_SHA256
+
+/* random sizes */
+#define SCTP_AUTH_RANDOM_SIZE_DEFAULT	32
+#define SCTP_AUTH_RANDOM_SIZE_REQUIRED	32
+
+/* union of all supported HMAC algorithm contexts */
+typedef union sctp_hash_context {
+	SCTP_SHA1_CTX sha1;
+#if defined(SCTP_SUPPORT_HMAC_SHA256)
+	SCTP_SHA256_CTX sha256;
+#endif
+} sctp_hash_context_t;
+
+typedef struct sctp_key {
+	uint32_t keylen;
+	uint8_t key[];
+} sctp_key_t;
+
+typedef struct sctp_shared_key {
+	LIST_ENTRY(sctp_shared_key) next;
+	sctp_key_t *key;	/* key text */
+	uint32_t refcount;	/* reference count */
+	uint16_t keyid;		/* shared key ID */
+	uint8_t deactivated;	/* key is deactivated */
+} sctp_sharedkey_t;
+
+LIST_HEAD(sctp_keyhead, sctp_shared_key);
+
+/* authentication chunks list */
+typedef struct sctp_auth_chklist {
+	uint8_t chunks[256];
+	uint8_t num_chunks;
+} sctp_auth_chklist_t;
+
+/* hmac algos supported list */
+typedef struct sctp_hmaclist {
+	uint16_t max_algo;	/* max algorithms allocated */
+	uint16_t num_algo;	/* num algorithms used */
+	uint16_t hmac[];
+} sctp_hmaclist_t;
+
+/* authentication info */
+typedef struct sctp_authinformation {
+	sctp_key_t *random;	/* local random key (concatenated) */
+	uint32_t random_len;	/* local random number length for param */
+	sctp_key_t *peer_random;/* peer's random key (concatenated) */
+	sctp_key_t *assoc_key;	/* cached concatenated send key */
+	sctp_key_t *recv_key;	/* cached concatenated recv key */
+	uint16_t active_keyid;	/* active send keyid */
+	uint16_t assoc_keyid;	/* current send keyid (cached) */
+	uint16_t recv_keyid;	/* last recv keyid (cached) */
+} sctp_authinfo_t;
+
+
+
+/*
+ * Macros
+ */
+#define sctp_auth_is_required_chunk(chunk, list) ((list == NULL) ? (0) : (list->chunks[chunk] != 0))
+
+/*
+ * function prototypes
+ */
+
+/* socket option api functions */
+extern sctp_auth_chklist_t *sctp_alloc_chunklist(void);
+extern void sctp_free_chunklist(sctp_auth_chklist_t *chklist);
+extern void sctp_clear_chunklist(sctp_auth_chklist_t *chklist);
+extern sctp_auth_chklist_t *sctp_copy_chunklist(sctp_auth_chklist_t *chklist);
+extern int sctp_auth_add_chunk(uint8_t chunk, sctp_auth_chklist_t *list);
+extern int sctp_auth_delete_chunk(uint8_t chunk, sctp_auth_chklist_t *list);
+extern size_t sctp_auth_get_chklist_size(const sctp_auth_chklist_t *list);
+extern int sctp_serialize_auth_chunks(const sctp_auth_chklist_t *list,
+    uint8_t *ptr);
+extern int sctp_pack_auth_chunks(const sctp_auth_chklist_t *list,
+    uint8_t *ptr);
+extern int sctp_unpack_auth_chunks(const uint8_t *ptr, uint8_t num_chunks,
+    sctp_auth_chklist_t *list);
+
+/* key handling */
+extern sctp_key_t *sctp_alloc_key(uint32_t keylen);
+extern void sctp_free_key(sctp_key_t *key);
+extern void sctp_print_key(sctp_key_t *key, const char *str);
+extern void sctp_show_key(sctp_key_t *key, const char *str);
+extern sctp_key_t *sctp_generate_random_key(uint32_t keylen);
+extern sctp_key_t *sctp_set_key(uint8_t *key, uint32_t keylen);
+extern sctp_key_t *sctp_compute_hashkey(sctp_key_t *key1, sctp_key_t *key2,
+    sctp_key_t *shared);
+
+/* shared key handling */
+extern sctp_sharedkey_t *sctp_alloc_sharedkey(void);
+extern void sctp_free_sharedkey(sctp_sharedkey_t *skey);
+extern sctp_sharedkey_t *sctp_find_sharedkey(struct sctp_keyhead *shared_keys,
+    uint16_t key_id);
+extern int sctp_insert_sharedkey(struct sctp_keyhead *shared_keys,
+    sctp_sharedkey_t *new_skey);
+extern int sctp_copy_skeylist(const struct sctp_keyhead *src,
+    struct sctp_keyhead *dest);
+/* ref counts on shared keys, by key id */
+extern void sctp_auth_key_acquire(struct sctp_tcb *stcb, uint16_t keyid);
+extern void sctp_auth_key_release(struct sctp_tcb *stcb, uint16_t keyid,
+    int so_locked);
+
+
+/* hmac list handling */
+extern sctp_hmaclist_t *sctp_alloc_hmaclist(uint16_t num_hmacs);
+extern void sctp_free_hmaclist(sctp_hmaclist_t *list);
+extern int sctp_auth_add_hmacid(sctp_hmaclist_t *list, uint16_t hmac_id);
+extern sctp_hmaclist_t *sctp_copy_hmaclist(sctp_hmaclist_t *list);
+extern sctp_hmaclist_t *sctp_default_supported_hmaclist(void);
+extern uint16_t sctp_negotiate_hmacid(sctp_hmaclist_t *peer,
+    sctp_hmaclist_t *local);
+extern int sctp_serialize_hmaclist(sctp_hmaclist_t *list, uint8_t *ptr);
+extern int sctp_verify_hmac_param(struct sctp_auth_hmac_algo *hmacs,
+    uint32_t num_hmacs);
+
+extern sctp_authinfo_t *sctp_alloc_authinfo(void);
+extern void sctp_free_authinfo(sctp_authinfo_t *authinfo);
+
+/* keyed-HMAC functions */
+extern uint32_t sctp_get_auth_chunk_len(uint16_t hmac_algo);
+extern uint32_t sctp_get_hmac_digest_len(uint16_t hmac_algo);
+extern uint32_t sctp_hmac(uint16_t hmac_algo, uint8_t *key, uint32_t keylen,
+    uint8_t *text, uint32_t textlen, uint8_t *digest);
+extern int sctp_verify_hmac(uint16_t hmac_algo, uint8_t *key, uint32_t keylen,
+    uint8_t *text, uint32_t textlen, uint8_t *digest, uint32_t digestlen);
+extern uint32_t sctp_compute_hmac(uint16_t hmac_algo, sctp_key_t *key,
+    uint8_t *text, uint32_t textlen, uint8_t *digest);
+extern int sctp_auth_is_supported_hmac(sctp_hmaclist_t *list, uint16_t id);
+
+/* mbuf versions */
+extern uint32_t sctp_hmac_m(uint16_t hmac_algo, uint8_t *key, uint32_t keylen,
+    struct mbuf *m, uint32_t m_offset, uint8_t *digest, uint32_t trailer);
+extern uint32_t sctp_compute_hmac_m(uint16_t hmac_algo, sctp_key_t *key,
+    struct mbuf *m, uint32_t m_offset, uint8_t *digest);
+
+/*
+ * authentication routines
+ */
+extern void sctp_clear_cachedkeys(struct sctp_tcb *stcb, uint16_t keyid);
+extern void sctp_clear_cachedkeys_ep(struct sctp_inpcb *inp, uint16_t keyid);
+extern int sctp_delete_sharedkey(struct sctp_tcb *stcb, uint16_t keyid);
+extern int sctp_delete_sharedkey_ep(struct sctp_inpcb *inp, uint16_t keyid);
+extern int sctp_auth_setactivekey(struct sctp_tcb *stcb, uint16_t keyid);
+extern int sctp_auth_setactivekey_ep(struct sctp_inpcb *inp, uint16_t keyid);
+extern int sctp_deact_sharedkey(struct sctp_tcb *stcb, uint16_t keyid);
+extern int sctp_deact_sharedkey_ep(struct sctp_inpcb *inp, uint16_t keyid);
+
+extern void sctp_auth_get_cookie_params(struct sctp_tcb *stcb, struct mbuf *m,
+    uint32_t offset, uint32_t length);
+extern void sctp_fill_hmac_digest_m(struct mbuf *m, uint32_t auth_offset,
+    struct sctp_auth_chunk *auth, struct sctp_tcb *stcb, uint16_t key_id);
+extern struct mbuf *sctp_add_auth_chunk(struct mbuf *m, struct mbuf **m_end,
+    struct sctp_auth_chunk **auth_ret, uint32_t *offset,
+    struct sctp_tcb *stcb, uint8_t chunk);
+extern int sctp_handle_auth(struct sctp_tcb *stcb, struct sctp_auth_chunk *ch,
+    struct mbuf *m, uint32_t offset);
+extern void sctp_notify_authentication(struct sctp_tcb *stcb,
+    uint32_t indication, uint16_t keyid, uint16_t alt_keyid, int so_locked);
+extern int sctp_validate_init_auth_params(struct mbuf *m, int offset,
+    int limit);
+extern void sctp_initialize_auth_params(struct sctp_inpcb *inp,
+    struct sctp_tcb *stcb);
+
+/* test functions */
+#ifdef SCTP_HMAC_TEST
+extern void sctp_test_hmac_sha1(void);
+extern void sctp_test_authkey(void);
+#endif
+#endif /* __SCTP_AUTH_H__ */