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v5.4
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 *  Shared Memory Communications over RDMA (SMC-R) and RoCE
  4 *
  5 *  CLC (connection layer control) handshake over initial TCP socket to
  6 *  prepare for RDMA traffic
  7 *
  8 *  Copyright IBM Corp. 2016, 2018
  9 *
 10 *  Author(s):  Ursula Braun <ubraun@linux.vnet.ibm.com>
 11 */
 12
 13#include <linux/in.h>
 14#include <linux/inetdevice.h>
 15#include <linux/if_ether.h>
 16#include <linux/sched/signal.h>
 
 
 17
 18#include <net/addrconf.h>
 19#include <net/sock.h>
 20#include <net/tcp.h>
 21
 22#include "smc.h"
 23#include "smc_core.h"
 24#include "smc_clc.h"
 25#include "smc_ib.h"
 26#include "smc_ism.h"
 27
 28#define SMCR_CLC_ACCEPT_CONFIRM_LEN 68
 29#define SMCD_CLC_ACCEPT_CONFIRM_LEN 48
 
 
 30
 31/* eye catcher "SMCR" EBCDIC for CLC messages */
 32static const char SMC_EYECATCHER[4] = {'\xe2', '\xd4', '\xc3', '\xd9'};
 33/* eye catcher "SMCD" EBCDIC for CLC messages */
 34static const char SMCD_EYECATCHER[4] = {'\xe2', '\xd4', '\xc3', '\xc4'};
 35
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 36/* check if received message has a correct header length and contains valid
 37 * heading and trailing eyecatchers
 38 */
 39static bool smc_clc_msg_hdr_valid(struct smc_clc_msg_hdr *clcm)
 40{
 41	struct smc_clc_msg_proposal_prefix *pclc_prfx;
 42	struct smc_clc_msg_accept_confirm *clc;
 43	struct smc_clc_msg_proposal *pclc;
 44	struct smc_clc_msg_decline *dclc;
 45	struct smc_clc_msg_trail *trl;
 46
 47	if (memcmp(clcm->eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER)) &&
 48	    memcmp(clcm->eyecatcher, SMCD_EYECATCHER, sizeof(SMCD_EYECATCHER)))
 49		return false;
 50	switch (clcm->type) {
 51	case SMC_CLC_PROPOSAL:
 52		if (clcm->path != SMC_TYPE_R && clcm->path != SMC_TYPE_D &&
 53		    clcm->path != SMC_TYPE_B)
 54			return false;
 55		pclc = (struct smc_clc_msg_proposal *)clcm;
 56		pclc_prfx = smc_clc_proposal_get_prefix(pclc);
 57		if (ntohs(pclc->hdr.length) !=
 58			sizeof(*pclc) + ntohs(pclc->iparea_offset) +
 59			sizeof(*pclc_prfx) +
 60			pclc_prfx->ipv6_prefixes_cnt *
 61				sizeof(struct smc_clc_ipv6_prefix) +
 62			sizeof(*trl))
 63			return false;
 64		trl = (struct smc_clc_msg_trail *)
 65			((u8 *)pclc + ntohs(pclc->hdr.length) - sizeof(*trl));
 66		break;
 67	case SMC_CLC_ACCEPT:
 68	case SMC_CLC_CONFIRM:
 69		if (clcm->path != SMC_TYPE_R && clcm->path != SMC_TYPE_D)
 70			return false;
 71		clc = (struct smc_clc_msg_accept_confirm *)clcm;
 72		if ((clcm->path == SMC_TYPE_R &&
 73		     ntohs(clc->hdr.length) != SMCR_CLC_ACCEPT_CONFIRM_LEN) ||
 74		    (clcm->path == SMC_TYPE_D &&
 75		     ntohs(clc->hdr.length) != SMCD_CLC_ACCEPT_CONFIRM_LEN))
 76			return false;
 77		trl = (struct smc_clc_msg_trail *)
 78			((u8 *)clc + ntohs(clc->hdr.length) - sizeof(*trl));
 
 79		break;
 80	case SMC_CLC_DECLINE:
 81		dclc = (struct smc_clc_msg_decline *)clcm;
 82		if (ntohs(dclc->hdr.length) != sizeof(*dclc))
 83			return false;
 84		trl = &dclc->trl;
 85		break;
 86	default:
 87		return false;
 88	}
 89	if (memcmp(trl->eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER)) &&
 
 90	    memcmp(trl->eyecatcher, SMCD_EYECATCHER, sizeof(SMCD_EYECATCHER)))
 91		return false;
 92	return true;
 93}
 94
 95/* find ipv4 addr on device and get the prefix len, fill CLC proposal msg */
 96static int smc_clc_prfx_set4_rcu(struct dst_entry *dst, __be32 ipv4,
 97				 struct smc_clc_msg_proposal_prefix *prop)
 98{
 99	struct in_device *in_dev = __in_dev_get_rcu(dst->dev);
100	const struct in_ifaddr *ifa;
101
102	if (!in_dev)
103		return -ENODEV;
104
105	in_dev_for_each_ifa_rcu(ifa, in_dev) {
106		if (!inet_ifa_match(ipv4, ifa))
107			continue;
108		prop->prefix_len = inet_mask_len(ifa->ifa_mask);
109		prop->outgoing_subnet = ifa->ifa_address & ifa->ifa_mask;
110		/* prop->ipv6_prefixes_cnt = 0; already done by memset before */
111		return 0;
112	}
113	return -ENOENT;
114}
115
116/* fill CLC proposal msg with ipv6 prefixes from device */
117static int smc_clc_prfx_set6_rcu(struct dst_entry *dst,
118				 struct smc_clc_msg_proposal_prefix *prop,
119				 struct smc_clc_ipv6_prefix *ipv6_prfx)
120{
121#if IS_ENABLED(CONFIG_IPV6)
122	struct inet6_dev *in6_dev = __in6_dev_get(dst->dev);
123	struct inet6_ifaddr *ifa;
124	int cnt = 0;
125
126	if (!in6_dev)
127		return -ENODEV;
128	/* use a maximum of 8 IPv6 prefixes from device */
129	list_for_each_entry(ifa, &in6_dev->addr_list, if_list) {
130		if (ipv6_addr_type(&ifa->addr) & IPV6_ADDR_LINKLOCAL)
131			continue;
132		ipv6_addr_prefix(&ipv6_prfx[cnt].prefix,
133				 &ifa->addr, ifa->prefix_len);
134		ipv6_prfx[cnt].prefix_len = ifa->prefix_len;
135		cnt++;
136		if (cnt == SMC_CLC_MAX_V6_PREFIX)
137			break;
138	}
139	prop->ipv6_prefixes_cnt = cnt;
140	if (cnt)
141		return 0;
142#endif
143	return -ENOENT;
144}
145
146/* retrieve and set prefixes in CLC proposal msg */
147static int smc_clc_prfx_set(struct socket *clcsock,
148			    struct smc_clc_msg_proposal_prefix *prop,
149			    struct smc_clc_ipv6_prefix *ipv6_prfx)
150{
151	struct dst_entry *dst = sk_dst_get(clcsock->sk);
152	struct sockaddr_storage addrs;
153	struct sockaddr_in6 *addr6;
154	struct sockaddr_in *addr;
155	int rc = -ENOENT;
156
157	memset(prop, 0, sizeof(*prop));
158	if (!dst) {
159		rc = -ENOTCONN;
160		goto out;
161	}
162	if (!dst->dev) {
163		rc = -ENODEV;
164		goto out_rel;
165	}
166	/* get address to which the internal TCP socket is bound */
167	kernel_getsockname(clcsock, (struct sockaddr *)&addrs);
 
168	/* analyze IP specific data of net_device belonging to TCP socket */
169	addr6 = (struct sockaddr_in6 *)&addrs;
170	rcu_read_lock();
171	if (addrs.ss_family == PF_INET) {
172		/* IPv4 */
173		addr = (struct sockaddr_in *)&addrs;
174		rc = smc_clc_prfx_set4_rcu(dst, addr->sin_addr.s_addr, prop);
175	} else if (ipv6_addr_v4mapped(&addr6->sin6_addr)) {
176		/* mapped IPv4 address - peer is IPv4 only */
177		rc = smc_clc_prfx_set4_rcu(dst, addr6->sin6_addr.s6_addr32[3],
178					   prop);
179	} else {
180		/* IPv6 */
181		rc = smc_clc_prfx_set6_rcu(dst, prop, ipv6_prfx);
182	}
183	rcu_read_unlock();
184out_rel:
185	dst_release(dst);
186out:
187	return rc;
188}
189
190/* match ipv4 addrs of dev against addr in CLC proposal */
191static int smc_clc_prfx_match4_rcu(struct net_device *dev,
192				   struct smc_clc_msg_proposal_prefix *prop)
193{
194	struct in_device *in_dev = __in_dev_get_rcu(dev);
195	const struct in_ifaddr *ifa;
196
197	if (!in_dev)
198		return -ENODEV;
199	in_dev_for_each_ifa_rcu(ifa, in_dev) {
200		if (prop->prefix_len == inet_mask_len(ifa->ifa_mask) &&
201		    inet_ifa_match(prop->outgoing_subnet, ifa))
202			return 0;
203	}
204
205	return -ENOENT;
206}
207
208/* match ipv6 addrs of dev against addrs in CLC proposal */
209static int smc_clc_prfx_match6_rcu(struct net_device *dev,
210				   struct smc_clc_msg_proposal_prefix *prop)
211{
212#if IS_ENABLED(CONFIG_IPV6)
213	struct inet6_dev *in6_dev = __in6_dev_get(dev);
214	struct smc_clc_ipv6_prefix *ipv6_prfx;
215	struct inet6_ifaddr *ifa;
216	int i, max;
217
218	if (!in6_dev)
219		return -ENODEV;
220	/* ipv6 prefix list starts behind smc_clc_msg_proposal_prefix */
221	ipv6_prfx = (struct smc_clc_ipv6_prefix *)((u8 *)prop + sizeof(*prop));
222	max = min_t(u8, prop->ipv6_prefixes_cnt, SMC_CLC_MAX_V6_PREFIX);
223	list_for_each_entry(ifa, &in6_dev->addr_list, if_list) {
224		if (ipv6_addr_type(&ifa->addr) & IPV6_ADDR_LINKLOCAL)
225			continue;
226		for (i = 0; i < max; i++) {
227			if (ifa->prefix_len == ipv6_prfx[i].prefix_len &&
228			    ipv6_prefix_equal(&ifa->addr, &ipv6_prfx[i].prefix,
229					      ifa->prefix_len))
230				return 0;
231		}
232	}
233#endif
234	return -ENOENT;
235}
236
237/* check if proposed prefixes match one of our device prefixes */
238int smc_clc_prfx_match(struct socket *clcsock,
239		       struct smc_clc_msg_proposal_prefix *prop)
240{
241	struct dst_entry *dst = sk_dst_get(clcsock->sk);
242	int rc;
243
244	if (!dst) {
245		rc = -ENOTCONN;
246		goto out;
247	}
248	if (!dst->dev) {
249		rc = -ENODEV;
250		goto out_rel;
251	}
252	rcu_read_lock();
253	if (!prop->ipv6_prefixes_cnt)
254		rc = smc_clc_prfx_match4_rcu(dst->dev, prop);
255	else
256		rc = smc_clc_prfx_match6_rcu(dst->dev, prop);
257	rcu_read_unlock();
258out_rel:
259	dst_release(dst);
260out:
261	return rc;
262}
263
264/* Wait for data on the tcp-socket, analyze received data
265 * Returns:
266 * 0 if success and it was not a decline that we received.
267 * SMC_CLC_DECL_REPLY if decline received for fallback w/o another decl send.
268 * clcsock error, -EINTR, -ECONNRESET, -EPROTO otherwise.
269 */
270int smc_clc_wait_msg(struct smc_sock *smc, void *buf, int buflen,
271		     u8 expected_type, unsigned long timeout)
272{
273	long rcvtimeo = smc->clcsock->sk->sk_rcvtimeo;
274	struct sock *clc_sk = smc->clcsock->sk;
275	struct smc_clc_msg_hdr *clcm = buf;
276	struct msghdr msg = {NULL, 0};
277	int reason_code = 0;
278	struct kvec vec = {buf, buflen};
279	int len, datlen;
 
280	int krflags;
281
282	/* peek the first few bytes to determine length of data to receive
283	 * so we don't consume any subsequent CLC message or payload data
284	 * in the TCP byte stream
285	 */
286	/*
287	 * Caller must make sure that buflen is no less than
288	 * sizeof(struct smc_clc_msg_hdr)
289	 */
290	krflags = MSG_PEEK | MSG_WAITALL;
291	clc_sk->sk_rcvtimeo = timeout;
292	iov_iter_kvec(&msg.msg_iter, READ, &vec, 1,
293			sizeof(struct smc_clc_msg_hdr));
294	len = sock_recvmsg(smc->clcsock, &msg, krflags);
295	if (signal_pending(current)) {
296		reason_code = -EINTR;
297		clc_sk->sk_err = EINTR;
298		smc->sk.sk_err = EINTR;
299		goto out;
300	}
301	if (clc_sk->sk_err) {
302		reason_code = -clc_sk->sk_err;
303		if (clc_sk->sk_err == EAGAIN &&
304		    expected_type == SMC_CLC_DECLINE)
305			clc_sk->sk_err = 0; /* reset for fallback usage */
306		else
307			smc->sk.sk_err = clc_sk->sk_err;
308		goto out;
309	}
310	if (!len) { /* peer has performed orderly shutdown */
311		smc->sk.sk_err = ECONNRESET;
312		reason_code = -ECONNRESET;
313		goto out;
314	}
315	if (len < 0) {
316		if (len != -EAGAIN || expected_type != SMC_CLC_DECLINE)
317			smc->sk.sk_err = -len;
318		reason_code = len;
319		goto out;
320	}
321	datlen = ntohs(clcm->length);
322	if ((len < sizeof(struct smc_clc_msg_hdr)) ||
323	    (datlen > buflen) ||
324	    (clcm->version != SMC_CLC_V1) ||
325	    (clcm->path != SMC_TYPE_R && clcm->path != SMC_TYPE_D &&
326	     clcm->path != SMC_TYPE_B) ||
327	    ((clcm->type != SMC_CLC_DECLINE) &&
328	     (clcm->type != expected_type))) {
329		smc->sk.sk_err = EPROTO;
330		reason_code = -EPROTO;
331		goto out;
332	}
333
334	/* receive the complete CLC message */
335	memset(&msg, 0, sizeof(struct msghdr));
336	iov_iter_kvec(&msg.msg_iter, READ, &vec, 1, datlen);
 
 
 
 
 
 
337	krflags = MSG_WAITALL;
338	len = sock_recvmsg(smc->clcsock, &msg, krflags);
339	if (len < datlen || !smc_clc_msg_hdr_valid(clcm)) {
340		smc->sk.sk_err = EPROTO;
341		reason_code = -EPROTO;
342		goto out;
343	}
 
 
 
 
 
 
 
 
 
 
 
 
 
344	if (clcm->type == SMC_CLC_DECLINE) {
345		struct smc_clc_msg_decline *dclc;
346
347		dclc = (struct smc_clc_msg_decline *)clcm;
348		reason_code = SMC_CLC_DECL_PEERDECL;
349		smc->peer_diagnosis = ntohl(dclc->peer_diagnosis);
350		if (((struct smc_clc_msg_decline *)buf)->hdr.flag) {
 
351			smc->conn.lgr->sync_err = 1;
352			smc_lgr_terminate(smc->conn.lgr);
353		}
354	}
355
356out:
357	clc_sk->sk_rcvtimeo = rcvtimeo;
358	return reason_code;
359}
360
361/* send CLC DECLINE message across internal TCP socket */
362int smc_clc_send_decline(struct smc_sock *smc, u32 peer_diag_info)
363{
364	struct smc_clc_msg_decline dclc;
365	struct msghdr msg;
366	struct kvec vec;
367	int len;
368
369	memset(&dclc, 0, sizeof(dclc));
370	memcpy(dclc.hdr.eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
371	dclc.hdr.type = SMC_CLC_DECLINE;
372	dclc.hdr.length = htons(sizeof(struct smc_clc_msg_decline));
373	dclc.hdr.version = SMC_CLC_V1;
374	dclc.hdr.flag = (peer_diag_info == SMC_CLC_DECL_SYNCERR) ? 1 : 0;
375	memcpy(dclc.id_for_peer, local_systemid, sizeof(local_systemid));
 
 
 
 
 
376	dclc.peer_diagnosis = htonl(peer_diag_info);
377	memcpy(dclc.trl.eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
378
379	memset(&msg, 0, sizeof(msg));
380	vec.iov_base = &dclc;
381	vec.iov_len = sizeof(struct smc_clc_msg_decline);
382	len = kernel_sendmsg(smc->clcsock, &msg, &vec, 1,
383			     sizeof(struct smc_clc_msg_decline));
384	if (len < 0 || len < sizeof(struct smc_clc_msg_decline))
385		len = -EPROTO;
386	return len > 0 ? 0 : len;
387}
388
389/* send CLC PROPOSAL message across internal TCP socket */
390int smc_clc_send_proposal(struct smc_sock *smc, int smc_type,
391			  struct smc_init_info *ini)
392{
393	struct smc_clc_ipv6_prefix ipv6_prfx[SMC_CLC_MAX_V6_PREFIX];
394	struct smc_clc_msg_proposal_prefix pclc_prfx;
395	struct smc_clc_msg_smcd pclc_smcd;
396	struct smc_clc_msg_proposal pclc;
397	struct smc_clc_msg_trail trl;
 
 
 
 
398	int len, i, plen, rc;
399	int reason_code = 0;
400	struct kvec vec[5];
401	struct msghdr msg;
402
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
403	/* retrieve ip prefixes for CLC proposal msg */
404	rc = smc_clc_prfx_set(smc->clcsock, &pclc_prfx, ipv6_prfx);
405	if (rc)
406		return SMC_CLC_DECL_CNFERR; /* configuration error */
 
 
 
 
 
 
 
 
 
 
 
 
407
408	/* send SMC Proposal CLC message */
409	plen = sizeof(pclc) + sizeof(pclc_prfx) +
410	       (pclc_prfx.ipv6_prefixes_cnt * sizeof(ipv6_prfx[0])) +
411	       sizeof(trl);
412	memset(&pclc, 0, sizeof(pclc));
413	memcpy(pclc.hdr.eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
414	pclc.hdr.type = SMC_CLC_PROPOSAL;
415	pclc.hdr.version = SMC_CLC_V1;		/* SMC version */
416	pclc.hdr.path = smc_type;
417	if (smc_type == SMC_TYPE_R || smc_type == SMC_TYPE_B) {
418		/* add SMC-R specifics */
419		memcpy(pclc.lcl.id_for_peer, local_systemid,
420		       sizeof(local_systemid));
421		memcpy(&pclc.lcl.gid, ini->ib_gid, SMC_GID_SIZE);
422		memcpy(&pclc.lcl.mac, &ini->ib_dev->mac[ini->ib_port - 1],
423		       ETH_ALEN);
424		pclc.iparea_offset = htons(0);
425	}
426	if (smc_type == SMC_TYPE_D || smc_type == SMC_TYPE_B) {
427		/* add SMC-D specifics */
428		memset(&pclc_smcd, 0, sizeof(pclc_smcd));
429		plen += sizeof(pclc_smcd);
430		pclc.iparea_offset = htons(SMC_CLC_PROPOSAL_MAX_OFFSET);
431		pclc_smcd.gid = ini->ism_dev->local_gid;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
432	}
433	pclc.hdr.length = htons(plen);
 
434
435	memcpy(trl.eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
436	memset(&msg, 0, sizeof(msg));
437	i = 0;
438	vec[i].iov_base = &pclc;
439	vec[i++].iov_len = sizeof(pclc);
440	if (smc_type == SMC_TYPE_D || smc_type == SMC_TYPE_B) {
441		vec[i].iov_base = &pclc_smcd;
442		vec[i++].iov_len = sizeof(pclc_smcd);
443	}
444	vec[i].iov_base = &pclc_prfx;
445	vec[i++].iov_len = sizeof(pclc_prfx);
446	if (pclc_prfx.ipv6_prefixes_cnt > 0) {
447		vec[i].iov_base = &ipv6_prfx[0];
448		vec[i++].iov_len = pclc_prfx.ipv6_prefixes_cnt *
449				   sizeof(ipv6_prfx[0]);
450	}
451	vec[i].iov_base = &trl;
452	vec[i++].iov_len = sizeof(trl);
 
 
 
 
 
 
 
 
 
 
 
453	/* due to the few bytes needed for clc-handshake this cannot block */
454	len = kernel_sendmsg(smc->clcsock, &msg, vec, i, plen);
455	if (len < 0) {
456		smc->sk.sk_err = smc->clcsock->sk->sk_err;
457		reason_code = -smc->sk.sk_err;
458	} else if (len < (int)sizeof(pclc)) {
459		reason_code = -ENETUNREACH;
460		smc->sk.sk_err = -reason_code;
461	}
462
 
463	return reason_code;
464}
465
466/* send CLC CONFIRM message across internal TCP socket */
467int smc_clc_send_confirm(struct smc_sock *smc)
 
 
468{
469	struct smc_connection *conn = &smc->conn;
470	struct smc_clc_msg_accept_confirm cclc;
471	struct smc_link *link;
472	int reason_code = 0;
 
473	struct msghdr msg;
474	struct kvec vec;
475	int len;
476
477	/* send SMC Confirm CLC msg */
478	memset(&cclc, 0, sizeof(cclc));
479	cclc.hdr.type = SMC_CLC_CONFIRM;
480	cclc.hdr.version = SMC_CLC_V1;		/* SMC version */
481	if (smc->conn.lgr->is_smcd) {
 
482		/* SMC-D specific settings */
483		memcpy(cclc.hdr.eyecatcher, SMCD_EYECATCHER,
484		       sizeof(SMCD_EYECATCHER));
485		cclc.hdr.path = SMC_TYPE_D;
486		cclc.hdr.length = htons(SMCD_CLC_ACCEPT_CONFIRM_LEN);
487		cclc.gid = conn->lgr->smcd->local_gid;
488		cclc.token = conn->rmb_desc->token;
489		cclc.dmbe_size = conn->rmbe_size_short;
490		cclc.dmbe_idx = 0;
491		memcpy(&cclc.linkid, conn->lgr->id, SMC_LGR_ID_SIZE);
492		memcpy(cclc.smcd_trl.eyecatcher, SMCD_EYECATCHER,
 
 
 
 
 
 
 
 
 
 
 
 
 
493		       sizeof(SMCD_EYECATCHER));
494	} else {
 
 
495		/* SMC-R specific settings */
496		link = &conn->lgr->lnk[SMC_SINGLE_LINK];
497		memcpy(cclc.hdr.eyecatcher, SMC_EYECATCHER,
498		       sizeof(SMC_EYECATCHER));
499		cclc.hdr.path = SMC_TYPE_R;
500		cclc.hdr.length = htons(SMCR_CLC_ACCEPT_CONFIRM_LEN);
501		memcpy(cclc.lcl.id_for_peer, local_systemid,
502		       sizeof(local_systemid));
503		memcpy(&cclc.lcl.gid, link->gid, SMC_GID_SIZE);
504		memcpy(&cclc.lcl.mac, &link->smcibdev->mac[link->ibport - 1],
505		       ETH_ALEN);
506		hton24(cclc.qpn, link->roce_qp->qp_num);
507		cclc.rmb_rkey =
508			htonl(conn->rmb_desc->mr_rx[SMC_SINGLE_LINK]->rkey);
509		cclc.rmbe_idx = 1; /* for now: 1 RMB = 1 RMBE */
510		cclc.rmbe_alert_token = htonl(conn->alert_token_local);
511		cclc.qp_mtu = min(link->path_mtu, link->peer_mtu);
512		cclc.rmbe_size = conn->rmbe_size_short;
513		cclc.rmb_dma_addr = cpu_to_be64((u64)sg_dma_address
514				(conn->rmb_desc->sgt[SMC_SINGLE_LINK].sgl));
515		hton24(cclc.psn, link->psn_initial);
516		memcpy(cclc.smcr_trl.eyecatcher, SMC_EYECATCHER,
517		       sizeof(SMC_EYECATCHER));
 
 
 
 
 
 
518	}
519
520	memset(&msg, 0, sizeof(msg));
521	vec.iov_base = &cclc;
522	vec.iov_len = ntohs(cclc.hdr.length);
523	len = kernel_sendmsg(smc->clcsock, &msg, &vec, 1,
524			     ntohs(cclc.hdr.length));
525	if (len < ntohs(cclc.hdr.length)) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
526		if (len >= 0) {
527			reason_code = -ENETUNREACH;
528			smc->sk.sk_err = -reason_code;
529		} else {
530			smc->sk.sk_err = smc->clcsock->sk->sk_err;
531			reason_code = -smc->sk.sk_err;
532		}
533	}
534	return reason_code;
535}
536
537/* send CLC ACCEPT message across internal TCP socket */
538int smc_clc_send_accept(struct smc_sock *new_smc, int srv_first_contact)
 
539{
540	struct smc_connection *conn = &new_smc->conn;
541	struct smc_clc_msg_accept_confirm aclc;
542	struct smc_link *link;
543	struct msghdr msg;
544	struct kvec vec;
545	int len;
546
547	memset(&aclc, 0, sizeof(aclc));
548	aclc.hdr.type = SMC_CLC_ACCEPT;
549	aclc.hdr.version = SMC_CLC_V1;		/* SMC version */
550	if (srv_first_contact)
551		aclc.hdr.flag = 1;
552
553	if (new_smc->conn.lgr->is_smcd) {
554		/* SMC-D specific settings */
555		aclc.hdr.length = htons(SMCD_CLC_ACCEPT_CONFIRM_LEN);
556		memcpy(aclc.hdr.eyecatcher, SMCD_EYECATCHER,
557		       sizeof(SMCD_EYECATCHER));
558		aclc.hdr.path = SMC_TYPE_D;
559		aclc.gid = conn->lgr->smcd->local_gid;
560		aclc.token = conn->rmb_desc->token;
561		aclc.dmbe_size = conn->rmbe_size_short;
562		aclc.dmbe_idx = 0;
563		memcpy(&aclc.linkid, conn->lgr->id, SMC_LGR_ID_SIZE);
564		memcpy(aclc.smcd_trl.eyecatcher, SMCD_EYECATCHER,
565		       sizeof(SMCD_EYECATCHER));
566	} else {
567		/* SMC-R specific settings */
568		aclc.hdr.length = htons(SMCR_CLC_ACCEPT_CONFIRM_LEN);
569		memcpy(aclc.hdr.eyecatcher, SMC_EYECATCHER,
570		       sizeof(SMC_EYECATCHER));
571		aclc.hdr.path = SMC_TYPE_R;
572		link = &conn->lgr->lnk[SMC_SINGLE_LINK];
573		memcpy(aclc.lcl.id_for_peer, local_systemid,
574		       sizeof(local_systemid));
575		memcpy(&aclc.lcl.gid, link->gid, SMC_GID_SIZE);
576		memcpy(&aclc.lcl.mac, link->smcibdev->mac[link->ibport - 1],
577		       ETH_ALEN);
578		hton24(aclc.qpn, link->roce_qp->qp_num);
579		aclc.rmb_rkey =
580			htonl(conn->rmb_desc->mr_rx[SMC_SINGLE_LINK]->rkey);
581		aclc.rmbe_idx = 1;		/* as long as 1 RMB = 1 RMBE */
582		aclc.rmbe_alert_token = htonl(conn->alert_token_local);
583		aclc.qp_mtu = link->path_mtu;
584		aclc.rmbe_size = conn->rmbe_size_short,
585		aclc.rmb_dma_addr = cpu_to_be64((u64)sg_dma_address
586				(conn->rmb_desc->sgt[SMC_SINGLE_LINK].sgl));
587		hton24(aclc.psn, link->psn_initial);
588		memcpy(aclc.smcr_trl.eyecatcher, SMC_EYECATCHER,
589		       sizeof(SMC_EYECATCHER));
590	}
591
592	memset(&msg, 0, sizeof(msg));
593	vec.iov_base = &aclc;
594	vec.iov_len = ntohs(aclc.hdr.length);
595	len = kernel_sendmsg(new_smc->clcsock, &msg, &vec, 1,
596			     ntohs(aclc.hdr.length));
597	if (len < ntohs(aclc.hdr.length))
598		len = len >= 0 ? -EPROTO : -new_smc->clcsock->sk->sk_err;
599
600	return len > 0 ? 0 : len;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
601}
v5.14.15
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 *  Shared Memory Communications over RDMA (SMC-R) and RoCE
  4 *
  5 *  CLC (connection layer control) handshake over initial TCP socket to
  6 *  prepare for RDMA traffic
  7 *
  8 *  Copyright IBM Corp. 2016, 2018
  9 *
 10 *  Author(s):  Ursula Braun <ubraun@linux.vnet.ibm.com>
 11 */
 12
 13#include <linux/in.h>
 14#include <linux/inetdevice.h>
 15#include <linux/if_ether.h>
 16#include <linux/sched/signal.h>
 17#include <linux/utsname.h>
 18#include <linux/ctype.h>
 19
 20#include <net/addrconf.h>
 21#include <net/sock.h>
 22#include <net/tcp.h>
 23
 24#include "smc.h"
 25#include "smc_core.h"
 26#include "smc_clc.h"
 27#include "smc_ib.h"
 28#include "smc_ism.h"
 29
 30#define SMCR_CLC_ACCEPT_CONFIRM_LEN 68
 31#define SMCD_CLC_ACCEPT_CONFIRM_LEN 48
 32#define SMCD_CLC_ACCEPT_CONFIRM_LEN_V2 78
 33#define SMC_CLC_RECV_BUF_LEN	100
 34
 35/* eye catcher "SMCR" EBCDIC for CLC messages */
 36static const char SMC_EYECATCHER[4] = {'\xe2', '\xd4', '\xc3', '\xd9'};
 37/* eye catcher "SMCD" EBCDIC for CLC messages */
 38static const char SMCD_EYECATCHER[4] = {'\xe2', '\xd4', '\xc3', '\xc4'};
 39
 40static u8 smc_hostname[SMC_MAX_HOSTNAME_LEN];
 41
 42/* check arriving CLC proposal */
 43static bool smc_clc_msg_prop_valid(struct smc_clc_msg_proposal *pclc)
 44{
 45	struct smc_clc_msg_proposal_prefix *pclc_prfx;
 46	struct smc_clc_smcd_v2_extension *smcd_v2_ext;
 47	struct smc_clc_msg_hdr *hdr = &pclc->hdr;
 48	struct smc_clc_v2_extension *v2_ext;
 49
 50	v2_ext = smc_get_clc_v2_ext(pclc);
 51	pclc_prfx = smc_clc_proposal_get_prefix(pclc);
 52	if (hdr->version == SMC_V1) {
 53		if (hdr->typev1 == SMC_TYPE_N)
 54			return false;
 55		if (ntohs(hdr->length) !=
 56			sizeof(*pclc) + ntohs(pclc->iparea_offset) +
 57			sizeof(*pclc_prfx) +
 58			pclc_prfx->ipv6_prefixes_cnt *
 59				sizeof(struct smc_clc_ipv6_prefix) +
 60			sizeof(struct smc_clc_msg_trail))
 61			return false;
 62	} else {
 63		if (ntohs(hdr->length) !=
 64			sizeof(*pclc) +
 65			sizeof(struct smc_clc_msg_smcd) +
 66			(hdr->typev1 != SMC_TYPE_N ?
 67				sizeof(*pclc_prfx) +
 68				pclc_prfx->ipv6_prefixes_cnt *
 69				sizeof(struct smc_clc_ipv6_prefix) : 0) +
 70			(hdr->typev2 != SMC_TYPE_N ?
 71				sizeof(*v2_ext) +
 72				v2_ext->hdr.eid_cnt * SMC_MAX_EID_LEN : 0) +
 73			(smcd_indicated(hdr->typev2) ?
 74				sizeof(*smcd_v2_ext) + v2_ext->hdr.ism_gid_cnt *
 75					sizeof(struct smc_clc_smcd_gid_chid) :
 76				0) +
 77			sizeof(struct smc_clc_msg_trail))
 78			return false;
 79	}
 80	return true;
 81}
 82
 83/* check arriving CLC accept or confirm */
 84static bool
 85smc_clc_msg_acc_conf_valid(struct smc_clc_msg_accept_confirm_v2 *clc_v2)
 86{
 87	struct smc_clc_msg_hdr *hdr = &clc_v2->hdr;
 88
 89	if (hdr->typev1 != SMC_TYPE_R && hdr->typev1 != SMC_TYPE_D)
 90		return false;
 91	if (hdr->version == SMC_V1) {
 92		if ((hdr->typev1 == SMC_TYPE_R &&
 93		     ntohs(hdr->length) != SMCR_CLC_ACCEPT_CONFIRM_LEN) ||
 94		    (hdr->typev1 == SMC_TYPE_D &&
 95		     ntohs(hdr->length) != SMCD_CLC_ACCEPT_CONFIRM_LEN))
 96			return false;
 97	} else {
 98		if (hdr->typev1 == SMC_TYPE_D &&
 99		    ntohs(hdr->length) != SMCD_CLC_ACCEPT_CONFIRM_LEN_V2 &&
100		    (ntohs(hdr->length) != SMCD_CLC_ACCEPT_CONFIRM_LEN_V2 +
101				sizeof(struct smc_clc_first_contact_ext)))
102			return false;
103	}
104	return true;
105}
106
107static void smc_clc_fill_fce(struct smc_clc_first_contact_ext *fce, int *len)
108{
109	memset(fce, 0, sizeof(*fce));
110	fce->os_type = SMC_CLC_OS_LINUX;
111	fce->release = SMC_RELEASE;
112	memcpy(fce->hostname, smc_hostname, sizeof(smc_hostname));
113	(*len) += sizeof(*fce);
114}
115
116/* check if received message has a correct header length and contains valid
117 * heading and trailing eyecatchers
118 */
119static bool smc_clc_msg_hdr_valid(struct smc_clc_msg_hdr *clcm, bool check_trl)
120{
121	struct smc_clc_msg_accept_confirm_v2 *clc_v2;
 
122	struct smc_clc_msg_proposal *pclc;
123	struct smc_clc_msg_decline *dclc;
124	struct smc_clc_msg_trail *trl;
125
126	if (memcmp(clcm->eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER)) &&
127	    memcmp(clcm->eyecatcher, SMCD_EYECATCHER, sizeof(SMCD_EYECATCHER)))
128		return false;
129	switch (clcm->type) {
130	case SMC_CLC_PROPOSAL:
 
 
 
131		pclc = (struct smc_clc_msg_proposal *)clcm;
132		if (!smc_clc_msg_prop_valid(pclc))
 
 
 
 
 
 
133			return false;
134		trl = (struct smc_clc_msg_trail *)
135			((u8 *)pclc + ntohs(pclc->hdr.length) - sizeof(*trl));
136		break;
137	case SMC_CLC_ACCEPT:
138	case SMC_CLC_CONFIRM:
139		clc_v2 = (struct smc_clc_msg_accept_confirm_v2 *)clcm;
140		if (!smc_clc_msg_acc_conf_valid(clc_v2))
 
 
 
 
 
141			return false;
142		trl = (struct smc_clc_msg_trail *)
143			((u8 *)clc_v2 + ntohs(clc_v2->hdr.length) -
144							sizeof(*trl));
145		break;
146	case SMC_CLC_DECLINE:
147		dclc = (struct smc_clc_msg_decline *)clcm;
148		if (ntohs(dclc->hdr.length) != sizeof(*dclc))
149			return false;
150		trl = &dclc->trl;
151		break;
152	default:
153		return false;
154	}
155	if (check_trl &&
156	    memcmp(trl->eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER)) &&
157	    memcmp(trl->eyecatcher, SMCD_EYECATCHER, sizeof(SMCD_EYECATCHER)))
158		return false;
159	return true;
160}
161
162/* find ipv4 addr on device and get the prefix len, fill CLC proposal msg */
163static int smc_clc_prfx_set4_rcu(struct dst_entry *dst, __be32 ipv4,
164				 struct smc_clc_msg_proposal_prefix *prop)
165{
166	struct in_device *in_dev = __in_dev_get_rcu(dst->dev);
167	const struct in_ifaddr *ifa;
168
169	if (!in_dev)
170		return -ENODEV;
171
172	in_dev_for_each_ifa_rcu(ifa, in_dev) {
173		if (!inet_ifa_match(ipv4, ifa))
174			continue;
175		prop->prefix_len = inet_mask_len(ifa->ifa_mask);
176		prop->outgoing_subnet = ifa->ifa_address & ifa->ifa_mask;
177		/* prop->ipv6_prefixes_cnt = 0; already done by memset before */
178		return 0;
179	}
180	return -ENOENT;
181}
182
183/* fill CLC proposal msg with ipv6 prefixes from device */
184static int smc_clc_prfx_set6_rcu(struct dst_entry *dst,
185				 struct smc_clc_msg_proposal_prefix *prop,
186				 struct smc_clc_ipv6_prefix *ipv6_prfx)
187{
188#if IS_ENABLED(CONFIG_IPV6)
189	struct inet6_dev *in6_dev = __in6_dev_get(dst->dev);
190	struct inet6_ifaddr *ifa;
191	int cnt = 0;
192
193	if (!in6_dev)
194		return -ENODEV;
195	/* use a maximum of 8 IPv6 prefixes from device */
196	list_for_each_entry(ifa, &in6_dev->addr_list, if_list) {
197		if (ipv6_addr_type(&ifa->addr) & IPV6_ADDR_LINKLOCAL)
198			continue;
199		ipv6_addr_prefix(&ipv6_prfx[cnt].prefix,
200				 &ifa->addr, ifa->prefix_len);
201		ipv6_prfx[cnt].prefix_len = ifa->prefix_len;
202		cnt++;
203		if (cnt == SMC_CLC_MAX_V6_PREFIX)
204			break;
205	}
206	prop->ipv6_prefixes_cnt = cnt;
207	if (cnt)
208		return 0;
209#endif
210	return -ENOENT;
211}
212
213/* retrieve and set prefixes in CLC proposal msg */
214static int smc_clc_prfx_set(struct socket *clcsock,
215			    struct smc_clc_msg_proposal_prefix *prop,
216			    struct smc_clc_ipv6_prefix *ipv6_prfx)
217{
218	struct dst_entry *dst = sk_dst_get(clcsock->sk);
219	struct sockaddr_storage addrs;
220	struct sockaddr_in6 *addr6;
221	struct sockaddr_in *addr;
222	int rc = -ENOENT;
223
 
224	if (!dst) {
225		rc = -ENOTCONN;
226		goto out;
227	}
228	if (!dst->dev) {
229		rc = -ENODEV;
230		goto out_rel;
231	}
232	/* get address to which the internal TCP socket is bound */
233	if (kernel_getsockname(clcsock, (struct sockaddr *)&addrs) < 0)
234		goto out_rel;
235	/* analyze IP specific data of net_device belonging to TCP socket */
236	addr6 = (struct sockaddr_in6 *)&addrs;
237	rcu_read_lock();
238	if (addrs.ss_family == PF_INET) {
239		/* IPv4 */
240		addr = (struct sockaddr_in *)&addrs;
241		rc = smc_clc_prfx_set4_rcu(dst, addr->sin_addr.s_addr, prop);
242	} else if (ipv6_addr_v4mapped(&addr6->sin6_addr)) {
243		/* mapped IPv4 address - peer is IPv4 only */
244		rc = smc_clc_prfx_set4_rcu(dst, addr6->sin6_addr.s6_addr32[3],
245					   prop);
246	} else {
247		/* IPv6 */
248		rc = smc_clc_prfx_set6_rcu(dst, prop, ipv6_prfx);
249	}
250	rcu_read_unlock();
251out_rel:
252	dst_release(dst);
253out:
254	return rc;
255}
256
257/* match ipv4 addrs of dev against addr in CLC proposal */
258static int smc_clc_prfx_match4_rcu(struct net_device *dev,
259				   struct smc_clc_msg_proposal_prefix *prop)
260{
261	struct in_device *in_dev = __in_dev_get_rcu(dev);
262	const struct in_ifaddr *ifa;
263
264	if (!in_dev)
265		return -ENODEV;
266	in_dev_for_each_ifa_rcu(ifa, in_dev) {
267		if (prop->prefix_len == inet_mask_len(ifa->ifa_mask) &&
268		    inet_ifa_match(prop->outgoing_subnet, ifa))
269			return 0;
270	}
271
272	return -ENOENT;
273}
274
275/* match ipv6 addrs of dev against addrs in CLC proposal */
276static int smc_clc_prfx_match6_rcu(struct net_device *dev,
277				   struct smc_clc_msg_proposal_prefix *prop)
278{
279#if IS_ENABLED(CONFIG_IPV6)
280	struct inet6_dev *in6_dev = __in6_dev_get(dev);
281	struct smc_clc_ipv6_prefix *ipv6_prfx;
282	struct inet6_ifaddr *ifa;
283	int i, max;
284
285	if (!in6_dev)
286		return -ENODEV;
287	/* ipv6 prefix list starts behind smc_clc_msg_proposal_prefix */
288	ipv6_prfx = (struct smc_clc_ipv6_prefix *)((u8 *)prop + sizeof(*prop));
289	max = min_t(u8, prop->ipv6_prefixes_cnt, SMC_CLC_MAX_V6_PREFIX);
290	list_for_each_entry(ifa, &in6_dev->addr_list, if_list) {
291		if (ipv6_addr_type(&ifa->addr) & IPV6_ADDR_LINKLOCAL)
292			continue;
293		for (i = 0; i < max; i++) {
294			if (ifa->prefix_len == ipv6_prfx[i].prefix_len &&
295			    ipv6_prefix_equal(&ifa->addr, &ipv6_prfx[i].prefix,
296					      ifa->prefix_len))
297				return 0;
298		}
299	}
300#endif
301	return -ENOENT;
302}
303
304/* check if proposed prefixes match one of our device prefixes */
305int smc_clc_prfx_match(struct socket *clcsock,
306		       struct smc_clc_msg_proposal_prefix *prop)
307{
308	struct dst_entry *dst = sk_dst_get(clcsock->sk);
309	int rc;
310
311	if (!dst) {
312		rc = -ENOTCONN;
313		goto out;
314	}
315	if (!dst->dev) {
316		rc = -ENODEV;
317		goto out_rel;
318	}
319	rcu_read_lock();
320	if (!prop->ipv6_prefixes_cnt)
321		rc = smc_clc_prfx_match4_rcu(dst->dev, prop);
322	else
323		rc = smc_clc_prfx_match6_rcu(dst->dev, prop);
324	rcu_read_unlock();
325out_rel:
326	dst_release(dst);
327out:
328	return rc;
329}
330
331/* Wait for data on the tcp-socket, analyze received data
332 * Returns:
333 * 0 if success and it was not a decline that we received.
334 * SMC_CLC_DECL_REPLY if decline received for fallback w/o another decl send.
335 * clcsock error, -EINTR, -ECONNRESET, -EPROTO otherwise.
336 */
337int smc_clc_wait_msg(struct smc_sock *smc, void *buf, int buflen,
338		     u8 expected_type, unsigned long timeout)
339{
340	long rcvtimeo = smc->clcsock->sk->sk_rcvtimeo;
341	struct sock *clc_sk = smc->clcsock->sk;
342	struct smc_clc_msg_hdr *clcm = buf;
343	struct msghdr msg = {NULL, 0};
344	int reason_code = 0;
345	struct kvec vec = {buf, buflen};
346	int len, datlen, recvlen;
347	bool check_trl = true;
348	int krflags;
349
350	/* peek the first few bytes to determine length of data to receive
351	 * so we don't consume any subsequent CLC message or payload data
352	 * in the TCP byte stream
353	 */
354	/*
355	 * Caller must make sure that buflen is no less than
356	 * sizeof(struct smc_clc_msg_hdr)
357	 */
358	krflags = MSG_PEEK | MSG_WAITALL;
359	clc_sk->sk_rcvtimeo = timeout;
360	iov_iter_kvec(&msg.msg_iter, READ, &vec, 1,
361			sizeof(struct smc_clc_msg_hdr));
362	len = sock_recvmsg(smc->clcsock, &msg, krflags);
363	if (signal_pending(current)) {
364		reason_code = -EINTR;
365		clc_sk->sk_err = EINTR;
366		smc->sk.sk_err = EINTR;
367		goto out;
368	}
369	if (clc_sk->sk_err) {
370		reason_code = -clc_sk->sk_err;
371		if (clc_sk->sk_err == EAGAIN &&
372		    expected_type == SMC_CLC_DECLINE)
373			clc_sk->sk_err = 0; /* reset for fallback usage */
374		else
375			smc->sk.sk_err = clc_sk->sk_err;
376		goto out;
377	}
378	if (!len) { /* peer has performed orderly shutdown */
379		smc->sk.sk_err = ECONNRESET;
380		reason_code = -ECONNRESET;
381		goto out;
382	}
383	if (len < 0) {
384		if (len != -EAGAIN || expected_type != SMC_CLC_DECLINE)
385			smc->sk.sk_err = -len;
386		reason_code = len;
387		goto out;
388	}
389	datlen = ntohs(clcm->length);
390	if ((len < sizeof(struct smc_clc_msg_hdr)) ||
391	    (clcm->version < SMC_V1) ||
 
 
 
392	    ((clcm->type != SMC_CLC_DECLINE) &&
393	     (clcm->type != expected_type))) {
394		smc->sk.sk_err = EPROTO;
395		reason_code = -EPROTO;
396		goto out;
397	}
398
399	/* receive the complete CLC message */
400	memset(&msg, 0, sizeof(struct msghdr));
401	if (datlen > buflen) {
402		check_trl = false;
403		recvlen = buflen;
404	} else {
405		recvlen = datlen;
406	}
407	iov_iter_kvec(&msg.msg_iter, READ, &vec, 1, recvlen);
408	krflags = MSG_WAITALL;
409	len = sock_recvmsg(smc->clcsock, &msg, krflags);
410	if (len < recvlen || !smc_clc_msg_hdr_valid(clcm, check_trl)) {
411		smc->sk.sk_err = EPROTO;
412		reason_code = -EPROTO;
413		goto out;
414	}
415	datlen -= len;
416	while (datlen) {
417		u8 tmp[SMC_CLC_RECV_BUF_LEN];
418
419		vec.iov_base = &tmp;
420		vec.iov_len = SMC_CLC_RECV_BUF_LEN;
421		/* receive remaining proposal message */
422		recvlen = datlen > SMC_CLC_RECV_BUF_LEN ?
423						SMC_CLC_RECV_BUF_LEN : datlen;
424		iov_iter_kvec(&msg.msg_iter, READ, &vec, 1, recvlen);
425		len = sock_recvmsg(smc->clcsock, &msg, krflags);
426		datlen -= len;
427	}
428	if (clcm->type == SMC_CLC_DECLINE) {
429		struct smc_clc_msg_decline *dclc;
430
431		dclc = (struct smc_clc_msg_decline *)clcm;
432		reason_code = SMC_CLC_DECL_PEERDECL;
433		smc->peer_diagnosis = ntohl(dclc->peer_diagnosis);
434		if (((struct smc_clc_msg_decline *)buf)->hdr.typev2 &
435						SMC_FIRST_CONTACT_MASK) {
436			smc->conn.lgr->sync_err = 1;
437			smc_lgr_terminate_sched(smc->conn.lgr);
438		}
439	}
440
441out:
442	clc_sk->sk_rcvtimeo = rcvtimeo;
443	return reason_code;
444}
445
446/* send CLC DECLINE message across internal TCP socket */
447int smc_clc_send_decline(struct smc_sock *smc, u32 peer_diag_info, u8 version)
448{
449	struct smc_clc_msg_decline dclc;
450	struct msghdr msg;
451	struct kvec vec;
452	int len;
453
454	memset(&dclc, 0, sizeof(dclc));
455	memcpy(dclc.hdr.eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
456	dclc.hdr.type = SMC_CLC_DECLINE;
457	dclc.hdr.length = htons(sizeof(struct smc_clc_msg_decline));
458	dclc.hdr.version = version;
459	dclc.os_type = version == SMC_V1 ? 0 : SMC_CLC_OS_LINUX;
460	dclc.hdr.typev2 = (peer_diag_info == SMC_CLC_DECL_SYNCERR) ?
461						SMC_FIRST_CONTACT_MASK : 0;
462	if ((!smc->conn.lgr || !smc->conn.lgr->is_smcd) &&
463	    smc_ib_is_valid_local_systemid())
464		memcpy(dclc.id_for_peer, local_systemid,
465		       sizeof(local_systemid));
466	dclc.peer_diagnosis = htonl(peer_diag_info);
467	memcpy(dclc.trl.eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
468
469	memset(&msg, 0, sizeof(msg));
470	vec.iov_base = &dclc;
471	vec.iov_len = sizeof(struct smc_clc_msg_decline);
472	len = kernel_sendmsg(smc->clcsock, &msg, &vec, 1,
473			     sizeof(struct smc_clc_msg_decline));
474	if (len < 0 || len < sizeof(struct smc_clc_msg_decline))
475		len = -EPROTO;
476	return len > 0 ? 0 : len;
477}
478
479/* send CLC PROPOSAL message across internal TCP socket */
480int smc_clc_send_proposal(struct smc_sock *smc, struct smc_init_info *ini)
 
481{
482	struct smc_clc_smcd_v2_extension *smcd_v2_ext;
483	struct smc_clc_msg_proposal_prefix *pclc_prfx;
484	struct smc_clc_msg_proposal *pclc_base;
485	struct smc_clc_smcd_gid_chid *gidchids;
486	struct smc_clc_msg_proposal_area *pclc;
487	struct smc_clc_ipv6_prefix *ipv6_prfx;
488	struct smc_clc_v2_extension *v2_ext;
489	struct smc_clc_msg_smcd *pclc_smcd;
490	struct smc_clc_msg_trail *trl;
491	int len, i, plen, rc;
492	int reason_code = 0;
493	struct kvec vec[8];
494	struct msghdr msg;
495
496	pclc = kzalloc(sizeof(*pclc), GFP_KERNEL);
497	if (!pclc)
498		return -ENOMEM;
499
500	pclc_base = &pclc->pclc_base;
501	pclc_smcd = &pclc->pclc_smcd;
502	pclc_prfx = &pclc->pclc_prfx;
503	ipv6_prfx = pclc->pclc_prfx_ipv6;
504	v2_ext = &pclc->pclc_v2_ext;
505	smcd_v2_ext = &pclc->pclc_smcd_v2_ext;
506	gidchids = pclc->pclc_gidchids;
507	trl = &pclc->pclc_trl;
508
509	pclc_base->hdr.version = SMC_V2;
510	pclc_base->hdr.typev1 = ini->smc_type_v1;
511	pclc_base->hdr.typev2 = ini->smc_type_v2;
512	plen = sizeof(*pclc_base) + sizeof(*pclc_smcd) + sizeof(*trl);
513
514	/* retrieve ip prefixes for CLC proposal msg */
515	if (ini->smc_type_v1 != SMC_TYPE_N) {
516		rc = smc_clc_prfx_set(smc->clcsock, pclc_prfx, ipv6_prfx);
517		if (rc) {
518			if (ini->smc_type_v2 == SMC_TYPE_N) {
519				kfree(pclc);
520				return SMC_CLC_DECL_CNFERR;
521			}
522			pclc_base->hdr.typev1 = SMC_TYPE_N;
523		} else {
524			pclc_base->iparea_offset = htons(sizeof(*pclc_smcd));
525			plen += sizeof(*pclc_prfx) +
526					pclc_prfx->ipv6_prefixes_cnt *
527					sizeof(ipv6_prfx[0]);
528		}
529	}
530
531	/* build SMC Proposal CLC message */
532	memcpy(pclc_base->hdr.eyecatcher, SMC_EYECATCHER,
533	       sizeof(SMC_EYECATCHER));
534	pclc_base->hdr.type = SMC_CLC_PROPOSAL;
535	if (smcr_indicated(ini->smc_type_v1)) {
 
 
 
 
 
536		/* add SMC-R specifics */
537		memcpy(pclc_base->lcl.id_for_peer, local_systemid,
538		       sizeof(local_systemid));
539		memcpy(pclc_base->lcl.gid, ini->ib_gid, SMC_GID_SIZE);
540		memcpy(pclc_base->lcl.mac, &ini->ib_dev->mac[ini->ib_port - 1],
541		       ETH_ALEN);
 
542	}
543	if (smcd_indicated(ini->smc_type_v1)) {
544		/* add SMC-D specifics */
545		if (ini->ism_dev[0]) {
546			pclc_smcd->ism.gid = htonll(ini->ism_dev[0]->local_gid);
547			pclc_smcd->ism.chid =
548				htons(smc_ism_get_chid(ini->ism_dev[0]));
549		}
550	}
551	if (ini->smc_type_v2 == SMC_TYPE_N) {
552		pclc_smcd->v2_ext_offset = 0;
553	} else {
554		u16 v2_ext_offset;
555		u8 *eid = NULL;
556
557		v2_ext_offset = sizeof(*pclc_smcd) -
558			offsetofend(struct smc_clc_msg_smcd, v2_ext_offset);
559		if (ini->smc_type_v1 != SMC_TYPE_N)
560			v2_ext_offset += sizeof(*pclc_prfx) +
561						pclc_prfx->ipv6_prefixes_cnt *
562						sizeof(ipv6_prfx[0]);
563		pclc_smcd->v2_ext_offset = htons(v2_ext_offset);
564		v2_ext->hdr.eid_cnt = 0;
565		v2_ext->hdr.ism_gid_cnt = ini->ism_offered_cnt;
566		v2_ext->hdr.flag.release = SMC_RELEASE;
567		v2_ext->hdr.flag.seid = 1;
568		v2_ext->hdr.smcd_v2_ext_offset = htons(sizeof(*v2_ext) -
569				offsetofend(struct smc_clnt_opts_area_hdr,
570					    smcd_v2_ext_offset) +
571				v2_ext->hdr.eid_cnt * SMC_MAX_EID_LEN);
572		if (ini->ism_dev[0])
573			smc_ism_get_system_eid(ini->ism_dev[0], &eid);
574		else
575			smc_ism_get_system_eid(ini->ism_dev[1], &eid);
576		if (eid)
577			memcpy(smcd_v2_ext->system_eid, eid, SMC_MAX_EID_LEN);
578		plen += sizeof(*v2_ext) + sizeof(*smcd_v2_ext);
579		if (ini->ism_offered_cnt) {
580			for (i = 1; i <= ini->ism_offered_cnt; i++) {
581				gidchids[i - 1].gid =
582					htonll(ini->ism_dev[i]->local_gid);
583				gidchids[i - 1].chid =
584					htons(smc_ism_get_chid(ini->ism_dev[i]));
585			}
586			plen += ini->ism_offered_cnt *
587				sizeof(struct smc_clc_smcd_gid_chid);
588		}
589	}
590	pclc_base->hdr.length = htons(plen);
591	memcpy(trl->eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
592
593	/* send SMC Proposal CLC message */
594	memset(&msg, 0, sizeof(msg));
595	i = 0;
596	vec[i].iov_base = pclc_base;
597	vec[i++].iov_len = sizeof(*pclc_base);
598	vec[i].iov_base = pclc_smcd;
599	vec[i++].iov_len = sizeof(*pclc_smcd);
600	if (ini->smc_type_v1 != SMC_TYPE_N) {
601		vec[i].iov_base = pclc_prfx;
602		vec[i++].iov_len = sizeof(*pclc_prfx);
603		if (pclc_prfx->ipv6_prefixes_cnt > 0) {
604			vec[i].iov_base = ipv6_prfx;
605			vec[i++].iov_len = pclc_prfx->ipv6_prefixes_cnt *
606					   sizeof(ipv6_prfx[0]);
607		}
608	}
609	if (ini->smc_type_v2 != SMC_TYPE_N) {
610		vec[i].iov_base = v2_ext;
611		vec[i++].iov_len = sizeof(*v2_ext);
612		vec[i].iov_base = smcd_v2_ext;
613		vec[i++].iov_len = sizeof(*smcd_v2_ext);
614		if (ini->ism_offered_cnt) {
615			vec[i].iov_base = gidchids;
616			vec[i++].iov_len = ini->ism_offered_cnt *
617					sizeof(struct smc_clc_smcd_gid_chid);
618		}
619	}
620	vec[i].iov_base = trl;
621	vec[i++].iov_len = sizeof(*trl);
622	/* due to the few bytes needed for clc-handshake this cannot block */
623	len = kernel_sendmsg(smc->clcsock, &msg, vec, i, plen);
624	if (len < 0) {
625		smc->sk.sk_err = smc->clcsock->sk->sk_err;
626		reason_code = -smc->sk.sk_err;
627	} else if (len < ntohs(pclc_base->hdr.length)) {
628		reason_code = -ENETUNREACH;
629		smc->sk.sk_err = -reason_code;
630	}
631
632	kfree(pclc);
633	return reason_code;
634}
635
636/* build and send CLC CONFIRM / ACCEPT message */
637static int smc_clc_send_confirm_accept(struct smc_sock *smc,
638				       struct smc_clc_msg_accept_confirm_v2 *clc_v2,
639				       int first_contact, u8 version)
640{
641	struct smc_connection *conn = &smc->conn;
642	struct smc_clc_msg_accept_confirm *clc;
643	struct smc_clc_first_contact_ext fce;
644	struct smc_clc_msg_trail trl;
645	struct kvec vec[3];
646	struct msghdr msg;
647	int i, len;
 
648
649	/* send SMC Confirm CLC msg */
650	clc = (struct smc_clc_msg_accept_confirm *)clc_v2;
651	clc->hdr.version = version;	/* SMC version */
652	if (first_contact)
653		clc->hdr.typev2 |= SMC_FIRST_CONTACT_MASK;
654	if (conn->lgr->is_smcd) {
655		/* SMC-D specific settings */
656		memcpy(clc->hdr.eyecatcher, SMCD_EYECATCHER,
657		       sizeof(SMCD_EYECATCHER));
658		clc->hdr.typev1 = SMC_TYPE_D;
659		clc->d0.gid = conn->lgr->smcd->local_gid;
660		clc->d0.token = conn->rmb_desc->token;
661		clc->d0.dmbe_size = conn->rmbe_size_short;
662		clc->d0.dmbe_idx = 0;
663		memcpy(&clc->d0.linkid, conn->lgr->id, SMC_LGR_ID_SIZE);
664		if (version == SMC_V1) {
665			clc->hdr.length = htons(SMCD_CLC_ACCEPT_CONFIRM_LEN);
666		} else {
667			u8 *eid = NULL;
668
669			clc_v2->chid = htons(smc_ism_get_chid(conn->lgr->smcd));
670			smc_ism_get_system_eid(conn->lgr->smcd, &eid);
671			if (eid)
672				memcpy(clc_v2->eid, eid, SMC_MAX_EID_LEN);
673			len = SMCD_CLC_ACCEPT_CONFIRM_LEN_V2;
674			if (first_contact)
675				smc_clc_fill_fce(&fce, &len);
676			clc_v2->hdr.length = htons(len);
677		}
678		memcpy(trl.eyecatcher, SMCD_EYECATCHER,
679		       sizeof(SMCD_EYECATCHER));
680	} else {
681		struct smc_link *link = conn->lnk;
682
683		/* SMC-R specific settings */
684		link = conn->lnk;
685		memcpy(clc->hdr.eyecatcher, SMC_EYECATCHER,
686		       sizeof(SMC_EYECATCHER));
687		clc->hdr.typev1 = SMC_TYPE_R;
688		clc->hdr.length = htons(SMCR_CLC_ACCEPT_CONFIRM_LEN);
689		memcpy(clc->r0.lcl.id_for_peer, local_systemid,
690		       sizeof(local_systemid));
691		memcpy(&clc->r0.lcl.gid, link->gid, SMC_GID_SIZE);
692		memcpy(&clc->r0.lcl.mac, &link->smcibdev->mac[link->ibport - 1],
693		       ETH_ALEN);
694		hton24(clc->r0.qpn, link->roce_qp->qp_num);
695		clc->r0.rmb_rkey =
696			htonl(conn->rmb_desc->mr_rx[link->link_idx]->rkey);
697		clc->r0.rmbe_idx = 1; /* for now: 1 RMB = 1 RMBE */
698		clc->r0.rmbe_alert_token = htonl(conn->alert_token_local);
699		switch (clc->hdr.type) {
700		case SMC_CLC_ACCEPT:
701			clc->r0.qp_mtu = link->path_mtu;
702			break;
703		case SMC_CLC_CONFIRM:
704			clc->r0.qp_mtu = min(link->path_mtu, link->peer_mtu);
705			break;
706		}
707		clc->r0.rmbe_size = conn->rmbe_size_short;
708		clc->r0.rmb_dma_addr = cpu_to_be64((u64)sg_dma_address
709				(conn->rmb_desc->sgt[link->link_idx].sgl));
710		hton24(clc->r0.psn, link->psn_initial);
711		memcpy(trl.eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
712	}
713
714	memset(&msg, 0, sizeof(msg));
715	i = 0;
716	vec[i].iov_base = clc_v2;
717	if (version > SMC_V1)
718		vec[i++].iov_len = SMCD_CLC_ACCEPT_CONFIRM_LEN_V2 - sizeof(trl);
719	else
720		vec[i++].iov_len = (clc->hdr.typev1 == SMC_TYPE_D ?
721						SMCD_CLC_ACCEPT_CONFIRM_LEN :
722						SMCR_CLC_ACCEPT_CONFIRM_LEN) -
723				   sizeof(trl);
724	if (version > SMC_V1 && first_contact) {
725		vec[i].iov_base = &fce;
726		vec[i++].iov_len = sizeof(fce);
727	}
728	vec[i].iov_base = &trl;
729	vec[i++].iov_len = sizeof(trl);
730	return kernel_sendmsg(smc->clcsock, &msg, vec, 1,
731			      ntohs(clc->hdr.length));
732}
733
734/* send CLC CONFIRM message across internal TCP socket */
735int smc_clc_send_confirm(struct smc_sock *smc, bool clnt_first_contact,
736			 u8 version)
737{
738	struct smc_clc_msg_accept_confirm_v2 cclc_v2;
739	int reason_code = 0;
740	int len;
741
742	/* send SMC Confirm CLC msg */
743	memset(&cclc_v2, 0, sizeof(cclc_v2));
744	cclc_v2.hdr.type = SMC_CLC_CONFIRM;
745	len = smc_clc_send_confirm_accept(smc, &cclc_v2, clnt_first_contact,
746					  version);
747	if (len < ntohs(cclc_v2.hdr.length)) {
748		if (len >= 0) {
749			reason_code = -ENETUNREACH;
750			smc->sk.sk_err = -reason_code;
751		} else {
752			smc->sk.sk_err = smc->clcsock->sk->sk_err;
753			reason_code = -smc->sk.sk_err;
754		}
755	}
756	return reason_code;
757}
758
759/* send CLC ACCEPT message across internal TCP socket */
760int smc_clc_send_accept(struct smc_sock *new_smc, bool srv_first_contact,
761			u8 version)
762{
763	struct smc_clc_msg_accept_confirm_v2 aclc_v2;
 
 
 
 
764	int len;
765
766	memset(&aclc_v2, 0, sizeof(aclc_v2));
767	aclc_v2.hdr.type = SMC_CLC_ACCEPT;
768	len = smc_clc_send_confirm_accept(new_smc, &aclc_v2, srv_first_contact,
769					  version);
770	if (len < ntohs(aclc_v2.hdr.length))
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
771		len = len >= 0 ? -EPROTO : -new_smc->clcsock->sk->sk_err;
772
773	return len > 0 ? 0 : len;
774}
775
776void smc_clc_get_hostname(u8 **host)
777{
778	*host = &smc_hostname[0];
779}
780
781void __init smc_clc_init(void)
782{
783	struct new_utsname *u;
784
785	memset(smc_hostname, _S, sizeof(smc_hostname)); /* ASCII blanks */
786	u = utsname();
787	memcpy(smc_hostname, u->nodename,
788	       min_t(size_t, strlen(u->nodename), sizeof(smc_hostname)));
789}