v4.19.13 snapshot.
diff --git a/include/net/sctp/constants.h b/include/net/sctp/constants.h
new file mode 100644
index 0000000..86f034b
--- /dev/null
+++ b/include/net/sctp/constants.h
@@ -0,0 +1,431 @@
+/* SCTP kernel implementation
+ * (C) Copyright IBM Corp. 2001, 2004
+ * Copyright (c) 1999-2000 Cisco, Inc.
+ * Copyright (c) 1999-2001 Motorola, Inc.
+ * Copyright (c) 2001 Intel Corp.
+ *
+ * This file is part of the SCTP kernel implementation
+ *
+ * This SCTP implementation 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, or (at your option)
+ * any later version.
+ *
+ * This SCTP implementation is distributed in the hope that it
+ * will be useful, but WITHOUT ANY WARRANTY; without even the implied
+ *                 ************************
+ * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GNU CC; see the file COPYING.  If not, see
+ * <http://www.gnu.org/licenses/>.
+ *
+ * Please send any bug reports or fixes you make to the
+ * email address(es):
+ *    lksctp developers <linux-sctp@vger.kernel.org>
+ *
+ * Written or modified by:
+ *   La Monte H.P. Yarroll <piggy@acm.org>
+ *   Karl Knutson          <karl@athena.chicago.il.us>
+ *   Randall Stewart       <randall@stewart.chicago.il.us>
+ *   Ken Morneau           <kmorneau@cisco.com>
+ *   Qiaobing Xie          <qxie1@motorola.com>
+ *   Xingang Guo           <xingang.guo@intel.com>
+ *   Sridhar Samudrala     <samudrala@us.ibm.com>
+ *   Daisy Chang           <daisyc@us.ibm.com>
+ */
+
+#ifndef __sctp_constants_h__
+#define __sctp_constants_h__
+
+#include <linux/sctp.h>
+#include <linux/ipv6.h> /* For ipv6hdr. */
+#include <net/tcp_states.h>  /* For TCP states used in enum sctp_sock_state */
+
+/* Value used for stream negotiation. */
+enum { SCTP_MAX_STREAM = 0xffff };
+enum { SCTP_DEFAULT_OUTSTREAMS = 10 };
+enum { SCTP_DEFAULT_INSTREAMS = SCTP_MAX_STREAM };
+
+/* Since CIDs are sparse, we need all four of the following
+ * symbols.  CIDs are dense through SCTP_CID_BASE_MAX.
+ */
+#define SCTP_CID_BASE_MAX		SCTP_CID_SHUTDOWN_COMPLETE
+
+#define SCTP_NUM_BASE_CHUNK_TYPES	(SCTP_CID_BASE_MAX + 1)
+
+#define SCTP_NUM_ADDIP_CHUNK_TYPES	2
+
+#define SCTP_NUM_PRSCTP_CHUNK_TYPES	1
+
+#define SCTP_NUM_RECONF_CHUNK_TYPES	1
+
+#define SCTP_NUM_AUTH_CHUNK_TYPES	1
+
+#define SCTP_NUM_CHUNK_TYPES		(SCTP_NUM_BASE_CHUNK_TYPES + \
+					 SCTP_NUM_ADDIP_CHUNK_TYPES +\
+					 SCTP_NUM_PRSCTP_CHUNK_TYPES +\
+					 SCTP_NUM_RECONF_CHUNK_TYPES +\
+					 SCTP_NUM_AUTH_CHUNK_TYPES)
+
+/* These are the different flavours of event.  */
+enum sctp_event {
+	SCTP_EVENT_T_CHUNK = 1,
+	SCTP_EVENT_T_TIMEOUT,
+	SCTP_EVENT_T_OTHER,
+	SCTP_EVENT_T_PRIMITIVE
+};
+
+/* As a convenience for the state machine, we append SCTP_EVENT_* and
+ * SCTP_ULP_* to the list of possible chunks.
+ */
+
+enum sctp_event_timeout {
+	SCTP_EVENT_TIMEOUT_NONE = 0,
+	SCTP_EVENT_TIMEOUT_T1_COOKIE,
+	SCTP_EVENT_TIMEOUT_T1_INIT,
+	SCTP_EVENT_TIMEOUT_T2_SHUTDOWN,
+	SCTP_EVENT_TIMEOUT_T3_RTX,
+	SCTP_EVENT_TIMEOUT_T4_RTO,
+	SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD,
+	SCTP_EVENT_TIMEOUT_HEARTBEAT,
+	SCTP_EVENT_TIMEOUT_RECONF,
+	SCTP_EVENT_TIMEOUT_SACK,
+	SCTP_EVENT_TIMEOUT_AUTOCLOSE,
+};
+
+#define SCTP_EVENT_TIMEOUT_MAX		SCTP_EVENT_TIMEOUT_AUTOCLOSE
+#define SCTP_NUM_TIMEOUT_TYPES		(SCTP_EVENT_TIMEOUT_MAX + 1)
+
+enum sctp_event_other {
+	SCTP_EVENT_NO_PENDING_TSN = 0,
+	SCTP_EVENT_ICMP_PROTO_UNREACH,
+};
+
+#define SCTP_EVENT_OTHER_MAX		SCTP_EVENT_ICMP_PROTO_UNREACH
+#define SCTP_NUM_OTHER_TYPES		(SCTP_EVENT_OTHER_MAX + 1)
+
+/* These are primitive requests from the ULP.  */
+enum sctp_event_primitive {
+	SCTP_PRIMITIVE_ASSOCIATE = 0,
+	SCTP_PRIMITIVE_SHUTDOWN,
+	SCTP_PRIMITIVE_ABORT,
+	SCTP_PRIMITIVE_SEND,
+	SCTP_PRIMITIVE_REQUESTHEARTBEAT,
+	SCTP_PRIMITIVE_ASCONF,
+	SCTP_PRIMITIVE_RECONF,
+};
+
+#define SCTP_EVENT_PRIMITIVE_MAX	SCTP_PRIMITIVE_RECONF
+#define SCTP_NUM_PRIMITIVE_TYPES	(SCTP_EVENT_PRIMITIVE_MAX + 1)
+
+/* We define here a utility type for manipulating subtypes.
+ * The subtype constructors all work like this:
+ *
+ *   union sctp_subtype foo = SCTP_ST_CHUNK(SCTP_CID_INIT);
+ */
+
+union sctp_subtype {
+	enum sctp_cid chunk;
+	enum sctp_event_timeout timeout;
+	enum sctp_event_other other;
+	enum sctp_event_primitive primitive;
+};
+
+#define SCTP_SUBTYPE_CONSTRUCTOR(_name, _type, _elt) \
+static inline union sctp_subtype	\
+SCTP_ST_## _name (_type _arg)		\
+{ union sctp_subtype _retval; _retval._elt = _arg; return _retval; }
+
+SCTP_SUBTYPE_CONSTRUCTOR(CHUNK,		enum sctp_cid,		chunk)
+SCTP_SUBTYPE_CONSTRUCTOR(TIMEOUT,	enum sctp_event_timeout, timeout)
+SCTP_SUBTYPE_CONSTRUCTOR(OTHER,		enum sctp_event_other,	other)
+SCTP_SUBTYPE_CONSTRUCTOR(PRIMITIVE,	enum sctp_event_primitive, primitive)
+
+
+#define sctp_chunk_is_data(a) (a->chunk_hdr->type == SCTP_CID_DATA || \
+			       a->chunk_hdr->type == SCTP_CID_I_DATA)
+
+/* Calculate the actual data size in a data chunk */
+#define SCTP_DATA_SNDSIZE(c) ((int)((unsigned long)(c->chunk_end) - \
+				    (unsigned long)(c->chunk_hdr) - \
+				    sctp_datachk_len(&c->asoc->stream)))
+
+/* Internal error codes */
+enum sctp_ierror {
+	SCTP_IERROR_NO_ERROR	        = 0,
+	SCTP_IERROR_BASE		= 1000,
+	SCTP_IERROR_NO_COOKIE,
+	SCTP_IERROR_BAD_SIG,
+	SCTP_IERROR_STALE_COOKIE,
+	SCTP_IERROR_NOMEM,
+	SCTP_IERROR_MALFORMED,
+	SCTP_IERROR_BAD_TAG,
+	SCTP_IERROR_BIG_GAP,
+	SCTP_IERROR_DUP_TSN,
+	SCTP_IERROR_HIGH_TSN,
+	SCTP_IERROR_IGNORE_TSN,
+	SCTP_IERROR_NO_DATA,
+	SCTP_IERROR_BAD_STREAM,
+	SCTP_IERROR_BAD_PORTS,
+	SCTP_IERROR_AUTH_BAD_HMAC,
+	SCTP_IERROR_AUTH_BAD_KEYID,
+	SCTP_IERROR_PROTO_VIOLATION,
+	SCTP_IERROR_ERROR,
+	SCTP_IERROR_ABORT,
+};
+
+
+
+/* SCTP state defines for internal state machine */
+enum sctp_state {
+
+	SCTP_STATE_CLOSED		= 0,
+	SCTP_STATE_COOKIE_WAIT		= 1,
+	SCTP_STATE_COOKIE_ECHOED	= 2,
+	SCTP_STATE_ESTABLISHED		= 3,
+	SCTP_STATE_SHUTDOWN_PENDING	= 4,
+	SCTP_STATE_SHUTDOWN_SENT	= 5,
+	SCTP_STATE_SHUTDOWN_RECEIVED	= 6,
+	SCTP_STATE_SHUTDOWN_ACK_SENT	= 7,
+
+};
+
+#define SCTP_STATE_MAX			SCTP_STATE_SHUTDOWN_ACK_SENT
+#define SCTP_STATE_NUM_STATES		(SCTP_STATE_MAX + 1)
+
+/* These are values for sk->state.
+ * For a UDP-style SCTP socket, the states are defined as follows
+ * - A socket in SCTP_SS_CLOSED state indicates that it is not willing to
+ *   accept new associations, but it can initiate the creation of new ones.
+ * - A socket in SCTP_SS_LISTENING state indicates that it is willing to
+ *   accept new  associations and can initiate the creation of new ones.
+ * - A socket in SCTP_SS_ESTABLISHED state indicates that it is a peeled off
+ *   socket with one association.
+ * For a TCP-style SCTP socket, the states are defined as follows
+ * - A socket in SCTP_SS_CLOSED state indicates that it is not willing to
+ *   accept new associations, but it can initiate the creation of new ones.
+ * - A socket in SCTP_SS_LISTENING state indicates that it is willing to
+ *   accept new associations, but cannot initiate the creation of new ones.
+ * - A socket in SCTP_SS_ESTABLISHED state indicates that it has a single 
+ *   association.
+ */
+enum sctp_sock_state {
+	SCTP_SS_CLOSED         = TCP_CLOSE,
+	SCTP_SS_LISTENING      = TCP_LISTEN,
+	SCTP_SS_ESTABLISHING   = TCP_SYN_SENT,
+	SCTP_SS_ESTABLISHED    = TCP_ESTABLISHED,
+	SCTP_SS_CLOSING        = TCP_CLOSE_WAIT,
+};
+
+/* These functions map various type to printable names.  */
+const char *sctp_cname(const union sctp_subtype id);	/* chunk types */
+const char *sctp_oname(const union sctp_subtype id);	/* other events */
+const char *sctp_tname(const union sctp_subtype id);	/* timeouts */
+const char *sctp_pname(const union sctp_subtype id);	/* primitives */
+
+/* This is a table of printable names of sctp_state_t's.  */
+extern const char *const sctp_state_tbl[];
+extern const char *const sctp_evttype_tbl[];
+extern const char *const sctp_status_tbl[];
+
+/* Maximum chunk length considering padding requirements. */
+enum { SCTP_MAX_CHUNK_LEN = ((1<<16) - sizeof(__u32)) };
+
+/* Encourage Cookie-Echo bundling by pre-fragmenting chunks a little
+ * harder (until reaching ESTABLISHED state).
+ */
+enum { SCTP_ARBITRARY_COOKIE_ECHO_LEN = 200 };
+
+/* Guess at how big to make the TSN mapping array.
+ * We guarantee that we can handle at least this big a gap between the
+ * cumulative ACK and the highest TSN.  In practice, we can often
+ * handle up to twice this value.
+ *
+ * NEVER make this more than 32767 (2^15-1).  The Gap Ack Blocks in a
+ * SACK (see  section 3.3.4) are only 16 bits, so 2*SCTP_TSN_MAP_SIZE
+ * must be less than 65535 (2^16 - 1), or we will have overflow
+ * problems creating SACK's.
+ */
+#define SCTP_TSN_MAP_INITIAL BITS_PER_LONG
+#define SCTP_TSN_MAP_INCREMENT SCTP_TSN_MAP_INITIAL
+#define SCTP_TSN_MAP_SIZE 4096
+
+/* We will not record more than this many duplicate TSNs between two
+ * SACKs.  The minimum PMTU is 512.  Remove all the headers and there
+ * is enough room for 117 duplicate reports.  Round down to the
+ * nearest power of 2.
+ */
+enum { SCTP_MAX_DUP_TSNS = 16 };
+enum { SCTP_MAX_GABS = 16 };
+
+/* Heartbeat interval - 30 secs */
+#define SCTP_DEFAULT_TIMEOUT_HEARTBEAT	(30*1000)
+
+/* Delayed sack timer - 200ms */
+#define SCTP_DEFAULT_TIMEOUT_SACK	(200)
+
+/* RTO.Initial              - 3  seconds
+ * RTO.Min                  - 1  second
+ * RTO.Max                  - 60 seconds
+ * RTO.Alpha                - 1/8
+ * RTO.Beta                 - 1/4
+ */
+#define SCTP_RTO_INITIAL	(3 * 1000)
+#define SCTP_RTO_MIN		(1 * 1000)
+#define SCTP_RTO_MAX		(60 * 1000)
+
+#define SCTP_RTO_ALPHA          3   /* 1/8 when converted to right shifts. */
+#define SCTP_RTO_BETA           2   /* 1/4 when converted to right shifts. */
+
+/* Maximum number of new data packets that can be sent in a burst.  */
+#define SCTP_DEFAULT_MAX_BURST		4
+
+#define SCTP_CLOCK_GRANULARITY	1	/* 1 jiffy */
+
+#define SCTP_DEFAULT_COOKIE_LIFE	(60 * 1000) /* 60 seconds */
+
+#define SCTP_DEFAULT_MINWINDOW	1500	/* default minimum rwnd size */
+#define SCTP_DEFAULT_MAXWINDOW	65535	/* default rwnd size */
+#define SCTP_DEFAULT_RWND_SHIFT  4	/* by default, update on 1/16 of
+					 * rcvbuf, which is 1/8 of initial
+					 * window
+					 */
+#define SCTP_DEFAULT_MAXSEGMENT 1500	/* MTU size, this is the limit
+                                         * to which we will raise the P-MTU.
+					 */
+#define SCTP_DEFAULT_MINSEGMENT 512	/* MTU size ... if no mtu disc */
+
+#define SCTP_SECRET_SIZE 32		/* Number of octets in a 256 bits. */
+
+#define SCTP_SIGNATURE_SIZE 20	        /* size of a SLA-1 signature */
+
+#define SCTP_COOKIE_MULTIPLE 32 /* Pad out our cookie to make our hash
+				 * functions simpler to write.
+				 */
+
+/* These return values describe the success or failure of a number of
+ * routines which form the lower interface to SCTP_outqueue.
+ */
+enum sctp_xmit {
+	SCTP_XMIT_OK,
+	SCTP_XMIT_PMTU_FULL,
+	SCTP_XMIT_RWND_FULL,
+	SCTP_XMIT_DELAY,
+};
+
+/* These are the commands for manipulating transports.  */
+enum sctp_transport_cmd {
+	SCTP_TRANSPORT_UP,
+	SCTP_TRANSPORT_DOWN,
+	SCTP_TRANSPORT_PF,
+};
+
+/* These are the address scopes defined mainly for IPv4 addresses
+ * based on draft of SCTP IPv4 scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>.
+ * These scopes are hopefully generic enough to be used on scoping both
+ * IPv4 and IPv6 addresses in SCTP.
+ * At this point, the IPv6 scopes will be mapped to these internal scopes
+ * as much as possible.
+ */
+enum sctp_scope {
+	SCTP_SCOPE_GLOBAL,		/* IPv4 global addresses */
+	SCTP_SCOPE_PRIVATE,		/* IPv4 private addresses */
+	SCTP_SCOPE_LINK,		/* IPv4 link local address */
+	SCTP_SCOPE_LOOPBACK,		/* IPv4 loopback address */
+	SCTP_SCOPE_UNUSABLE,		/* IPv4 unusable addresses */
+};
+
+enum {
+	SCTP_SCOPE_POLICY_DISABLE,	/* Disable IPv4 address scoping */
+	SCTP_SCOPE_POLICY_ENABLE,	/* Enable IPv4 address scoping */
+	SCTP_SCOPE_POLICY_PRIVATE,	/* Follow draft but allow IPv4 private addresses */
+	SCTP_SCOPE_POLICY_LINK,		/* Follow draft but allow IPv4 link local addresses */
+};
+
+#define SCTP_SCOPE_POLICY_MAX	SCTP_SCOPE_POLICY_LINK
+
+/* Based on IPv4 scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>,
+ * SCTP IPv4 unusable addresses: 0.0.0.0/8, 224.0.0.0/4, 198.18.0.0/24,
+ * 192.88.99.0/24.
+ * Also, RFC 8.4, non-unicast addresses are not considered valid SCTP
+ * addresses.
+ */
+#define IS_IPV4_UNUSABLE_ADDRESS(a)	    \
+	((htonl(INADDR_BROADCAST) == a) ||  \
+	 ipv4_is_multicast(a) ||	    \
+	 ipv4_is_zeronet(a) ||		    \
+	 ipv4_is_test_198(a) ||		    \
+	 ipv4_is_anycast_6to4(a))
+
+/* Flags used for the bind address copy functions.  */
+#define SCTP_ADDR6_ALLOWED	0x00000001	/* IPv6 address is allowed by
+						   local sock family */
+#define SCTP_ADDR4_PEERSUPP	0x00000002	/* IPv4 address is supported by
+						   peer */
+#define SCTP_ADDR6_PEERSUPP	0x00000004	/* IPv6 address is supported by
+						   peer */
+
+/* Reasons to retransmit. */
+enum sctp_retransmit_reason {
+	SCTP_RTXR_T3_RTX,
+	SCTP_RTXR_FAST_RTX,
+	SCTP_RTXR_PMTUD,
+	SCTP_RTXR_T1_RTX,
+};
+
+/* Reasons to lower cwnd. */
+enum sctp_lower_cwnd {
+	SCTP_LOWER_CWND_T3_RTX,
+	SCTP_LOWER_CWND_FAST_RTX,
+	SCTP_LOWER_CWND_ECNE,
+	SCTP_LOWER_CWND_INACTIVE,
+};
+
+
+/* SCTP-AUTH Necessary constants */
+
+/* SCTP-AUTH, Section 3.3
+ *
+ *  The following Table 2 shows the currently defined values for HMAC
+ *  identifiers.
+ *
+ *  +-----------------+--------------------------+
+ *  | HMAC Identifier | Message Digest Algorithm |
+ *  +-----------------+--------------------------+
+ *  | 0               | Reserved                 |
+ *  | 1               | SHA-1 defined in [8]     |
+ *  | 2               | Reserved                 |
+ *  | 3               | SHA-256 defined in [8]   |
+ *  +-----------------+--------------------------+
+ */
+enum {
+	SCTP_AUTH_HMAC_ID_RESERVED_0,
+	SCTP_AUTH_HMAC_ID_SHA1,
+	SCTP_AUTH_HMAC_ID_RESERVED_2,
+#if defined (CONFIG_CRYPTO_SHA256) || defined (CONFIG_CRYPTO_SHA256_MODULE)
+	SCTP_AUTH_HMAC_ID_SHA256,
+#endif
+	__SCTP_AUTH_HMAC_MAX
+};
+
+#define SCTP_AUTH_HMAC_ID_MAX	__SCTP_AUTH_HMAC_MAX - 1
+#define SCTP_AUTH_NUM_HMACS 	__SCTP_AUTH_HMAC_MAX
+#define SCTP_SHA1_SIG_SIZE 20
+#define SCTP_SHA256_SIG_SIZE 32
+
+/*  SCTP-AUTH, Section 3.2
+ *     The chunk types for INIT, INIT-ACK, SHUTDOWN-COMPLETE and AUTH chunks
+ *     MUST NOT be listed in the CHUNKS parameter
+ */
+#define SCTP_NUM_NOAUTH_CHUNKS	4
+#define SCTP_AUTH_MAX_CHUNKS	(SCTP_NUM_CHUNK_TYPES - SCTP_NUM_NOAUTH_CHUNKS)
+
+/* SCTP-AUTH Section 6.1
+ * The RANDOM parameter MUST contain a 32 byte random number.
+ */
+#define SCTP_AUTH_RANDOM_LENGTH 32
+
+#endif /* __sctp_constants_h__ */