xref: /linux/net/smc/smc_clc.c (revision ea8a163e02d6925773129e2dd86e419e491b791d)
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 #include "smc_netlink.h"
30 
31 #define SMCR_CLC_ACCEPT_CONFIRM_LEN 68
32 #define SMCD_CLC_ACCEPT_CONFIRM_LEN 48
33 #define SMCD_CLC_ACCEPT_CONFIRM_LEN_V2 78
34 #define SMCR_CLC_ACCEPT_CONFIRM_LEN_V2 108
35 #define SMC_CLC_RECV_BUF_LEN	100
36 
37 /* eye catcher "SMCR" EBCDIC for CLC messages */
38 static const char SMC_EYECATCHER[4] = {'\xe2', '\xd4', '\xc3', '\xd9'};
39 /* eye catcher "SMCD" EBCDIC for CLC messages */
40 static const char SMCD_EYECATCHER[4] = {'\xe2', '\xd4', '\xc3', '\xc4'};
41 
42 static u8 smc_hostname[SMC_MAX_HOSTNAME_LEN];
43 
44 struct smc_clc_eid_table {
45 	rwlock_t lock;
46 	struct list_head list;
47 	u8 ueid_cnt;
48 	u8 seid_enabled;
49 };
50 
51 static struct smc_clc_eid_table smc_clc_eid_table;
52 
53 struct smc_clc_eid_entry {
54 	struct list_head list;
55 	u8 eid[SMC_MAX_EID_LEN];
56 };
57 
58 /* The size of a user EID is 32 characters.
59  * Valid characters should be (single-byte character set) A-Z, 0-9, '.' and '-'.
60  * Blanks should only be used to pad to the expected size.
61  * First character must be alphanumeric.
62  */
63 static bool smc_clc_ueid_valid(char *ueid)
64 {
65 	char *end = ueid + SMC_MAX_EID_LEN;
66 
67 	while (--end >= ueid && isspace(*end))
68 		;
69 	if (end < ueid)
70 		return false;
71 	if (!isalnum(*ueid) || islower(*ueid))
72 		return false;
73 	while (ueid <= end) {
74 		if ((!isalnum(*ueid) || islower(*ueid)) && *ueid != '.' &&
75 		    *ueid != '-')
76 			return false;
77 		ueid++;
78 	}
79 	return true;
80 }
81 
82 static int smc_clc_ueid_add(char *ueid)
83 {
84 	struct smc_clc_eid_entry *new_ueid, *tmp_ueid;
85 	int rc;
86 
87 	if (!smc_clc_ueid_valid(ueid))
88 		return -EINVAL;
89 
90 	/* add a new ueid entry to the ueid table if there isn't one */
91 	new_ueid = kzalloc(sizeof(*new_ueid), GFP_KERNEL);
92 	if (!new_ueid)
93 		return -ENOMEM;
94 	memcpy(new_ueid->eid, ueid, SMC_MAX_EID_LEN);
95 
96 	write_lock(&smc_clc_eid_table.lock);
97 	if (smc_clc_eid_table.ueid_cnt >= SMC_MAX_UEID) {
98 		rc = -ERANGE;
99 		goto err_out;
100 	}
101 	list_for_each_entry(tmp_ueid, &smc_clc_eid_table.list, list) {
102 		if (!memcmp(tmp_ueid->eid, ueid, SMC_MAX_EID_LEN)) {
103 			rc = -EEXIST;
104 			goto err_out;
105 		}
106 	}
107 	list_add_tail(&new_ueid->list, &smc_clc_eid_table.list);
108 	smc_clc_eid_table.ueid_cnt++;
109 	write_unlock(&smc_clc_eid_table.lock);
110 	return 0;
111 
112 err_out:
113 	write_unlock(&smc_clc_eid_table.lock);
114 	kfree(new_ueid);
115 	return rc;
116 }
117 
118 int smc_clc_ueid_count(void)
119 {
120 	int count;
121 
122 	read_lock(&smc_clc_eid_table.lock);
123 	count = smc_clc_eid_table.ueid_cnt;
124 	read_unlock(&smc_clc_eid_table.lock);
125 
126 	return count;
127 }
128 
129 int smc_nl_add_ueid(struct sk_buff *skb, struct genl_info *info)
130 {
131 	struct nlattr *nla_ueid = info->attrs[SMC_NLA_EID_TABLE_ENTRY];
132 	char *ueid;
133 
134 	if (!nla_ueid || nla_len(nla_ueid) != SMC_MAX_EID_LEN + 1)
135 		return -EINVAL;
136 	ueid = (char *)nla_data(nla_ueid);
137 
138 	return smc_clc_ueid_add(ueid);
139 }
140 
141 /* remove one or all ueid entries from the table */
142 static int smc_clc_ueid_remove(char *ueid)
143 {
144 	struct smc_clc_eid_entry *lst_ueid, *tmp_ueid;
145 	int rc = -ENOENT;
146 
147 	/* remove table entry */
148 	write_lock(&smc_clc_eid_table.lock);
149 	list_for_each_entry_safe(lst_ueid, tmp_ueid, &smc_clc_eid_table.list,
150 				 list) {
151 		if (!ueid || !memcmp(lst_ueid->eid, ueid, SMC_MAX_EID_LEN)) {
152 			list_del(&lst_ueid->list);
153 			smc_clc_eid_table.ueid_cnt--;
154 			kfree(lst_ueid);
155 			rc = 0;
156 		}
157 	}
158 	if (!rc && !smc_clc_eid_table.ueid_cnt) {
159 		smc_clc_eid_table.seid_enabled = 1;
160 		rc = -EAGAIN;	/* indicate success and enabling of seid */
161 	}
162 	write_unlock(&smc_clc_eid_table.lock);
163 	return rc;
164 }
165 
166 int smc_nl_remove_ueid(struct sk_buff *skb, struct genl_info *info)
167 {
168 	struct nlattr *nla_ueid = info->attrs[SMC_NLA_EID_TABLE_ENTRY];
169 	char *ueid;
170 
171 	if (!nla_ueid || nla_len(nla_ueid) != SMC_MAX_EID_LEN + 1)
172 		return -EINVAL;
173 	ueid = (char *)nla_data(nla_ueid);
174 
175 	return smc_clc_ueid_remove(ueid);
176 }
177 
178 int smc_nl_flush_ueid(struct sk_buff *skb, struct genl_info *info)
179 {
180 	smc_clc_ueid_remove(NULL);
181 	return 0;
182 }
183 
184 static int smc_nl_ueid_dumpinfo(struct sk_buff *skb, u32 portid, u32 seq,
185 				u32 flags, char *ueid)
186 {
187 	char ueid_str[SMC_MAX_EID_LEN + 1];
188 	void *hdr;
189 
190 	hdr = genlmsg_put(skb, portid, seq, &smc_gen_nl_family,
191 			  flags, SMC_NETLINK_DUMP_UEID);
192 	if (!hdr)
193 		return -ENOMEM;
194 	snprintf(ueid_str, sizeof(ueid_str), "%s", ueid);
195 	if (nla_put_string(skb, SMC_NLA_EID_TABLE_ENTRY, ueid_str)) {
196 		genlmsg_cancel(skb, hdr);
197 		return -EMSGSIZE;
198 	}
199 	genlmsg_end(skb, hdr);
200 	return 0;
201 }
202 
203 static int _smc_nl_ueid_dump(struct sk_buff *skb, u32 portid, u32 seq,
204 			     int start_idx)
205 {
206 	struct smc_clc_eid_entry *lst_ueid;
207 	int idx = 0;
208 
209 	read_lock(&smc_clc_eid_table.lock);
210 	list_for_each_entry(lst_ueid, &smc_clc_eid_table.list, list) {
211 		if (idx++ < start_idx)
212 			continue;
213 		if (smc_nl_ueid_dumpinfo(skb, portid, seq, NLM_F_MULTI,
214 					 lst_ueid->eid)) {
215 			--idx;
216 			break;
217 		}
218 	}
219 	read_unlock(&smc_clc_eid_table.lock);
220 	return idx;
221 }
222 
223 int smc_nl_dump_ueid(struct sk_buff *skb, struct netlink_callback *cb)
224 {
225 	struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
226 	int idx;
227 
228 	idx = _smc_nl_ueid_dump(skb, NETLINK_CB(cb->skb).portid,
229 				cb->nlh->nlmsg_seq, cb_ctx->pos[0]);
230 
231 	cb_ctx->pos[0] = idx;
232 	return skb->len;
233 }
234 
235 int smc_nl_dump_seid(struct sk_buff *skb, struct netlink_callback *cb)
236 {
237 	struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
238 	char seid_str[SMC_MAX_EID_LEN + 1];
239 	u8 seid_enabled;
240 	void *hdr;
241 	u8 *seid;
242 
243 	if (cb_ctx->pos[0])
244 		return skb->len;
245 
246 	hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
247 			  &smc_gen_nl_family, NLM_F_MULTI,
248 			  SMC_NETLINK_DUMP_SEID);
249 	if (!hdr)
250 		return -ENOMEM;
251 	if (!smc_ism_is_v2_capable())
252 		goto end;
253 
254 	smc_ism_get_system_eid(&seid);
255 	snprintf(seid_str, sizeof(seid_str), "%s", seid);
256 	if (nla_put_string(skb, SMC_NLA_SEID_ENTRY, seid_str))
257 		goto err;
258 	read_lock(&smc_clc_eid_table.lock);
259 	seid_enabled = smc_clc_eid_table.seid_enabled;
260 	read_unlock(&smc_clc_eid_table.lock);
261 	if (nla_put_u8(skb, SMC_NLA_SEID_ENABLED, seid_enabled))
262 		goto err;
263 end:
264 	genlmsg_end(skb, hdr);
265 	cb_ctx->pos[0]++;
266 	return skb->len;
267 err:
268 	genlmsg_cancel(skb, hdr);
269 	return -EMSGSIZE;
270 }
271 
272 int smc_nl_enable_seid(struct sk_buff *skb, struct genl_info *info)
273 {
274 	write_lock(&smc_clc_eid_table.lock);
275 	smc_clc_eid_table.seid_enabled = 1;
276 	write_unlock(&smc_clc_eid_table.lock);
277 	return 0;
278 }
279 
280 int smc_nl_disable_seid(struct sk_buff *skb, struct genl_info *info)
281 {
282 	int rc = 0;
283 
284 	write_lock(&smc_clc_eid_table.lock);
285 	if (!smc_clc_eid_table.ueid_cnt)
286 		rc = -ENOENT;
287 	else
288 		smc_clc_eid_table.seid_enabled = 0;
289 	write_unlock(&smc_clc_eid_table.lock);
290 	return rc;
291 }
292 
293 static bool _smc_clc_match_ueid(u8 *peer_ueid)
294 {
295 	struct smc_clc_eid_entry *tmp_ueid;
296 
297 	list_for_each_entry(tmp_ueid, &smc_clc_eid_table.list, list) {
298 		if (!memcmp(tmp_ueid->eid, peer_ueid, SMC_MAX_EID_LEN))
299 			return true;
300 	}
301 	return false;
302 }
303 
304 bool smc_clc_match_eid(u8 *negotiated_eid,
305 		       struct smc_clc_v2_extension *smc_v2_ext,
306 		       u8 *peer_eid, u8 *local_eid)
307 {
308 	bool match = false;
309 	int i;
310 
311 	negotiated_eid[0] = 0;
312 	read_lock(&smc_clc_eid_table.lock);
313 	if (peer_eid && local_eid &&
314 	    smc_clc_eid_table.seid_enabled &&
315 	    smc_v2_ext->hdr.flag.seid &&
316 	    !memcmp(peer_eid, local_eid, SMC_MAX_EID_LEN)) {
317 		memcpy(negotiated_eid, peer_eid, SMC_MAX_EID_LEN);
318 		match = true;
319 		goto out;
320 	}
321 
322 	for (i = 0; i < smc_v2_ext->hdr.eid_cnt; i++) {
323 		if (_smc_clc_match_ueid(smc_v2_ext->user_eids[i])) {
324 			memcpy(negotiated_eid, smc_v2_ext->user_eids[i],
325 			       SMC_MAX_EID_LEN);
326 			match = true;
327 			goto out;
328 		}
329 	}
330 out:
331 	read_unlock(&smc_clc_eid_table.lock);
332 	return match;
333 }
334 
335 /* check arriving CLC proposal */
336 static bool smc_clc_msg_prop_valid(struct smc_clc_msg_proposal *pclc)
337 {
338 	struct smc_clc_msg_proposal_prefix *pclc_prfx;
339 	struct smc_clc_smcd_v2_extension *smcd_v2_ext;
340 	struct smc_clc_msg_hdr *hdr = &pclc->hdr;
341 	struct smc_clc_v2_extension *v2_ext;
342 
343 	v2_ext = smc_get_clc_v2_ext(pclc);
344 	pclc_prfx = smc_clc_proposal_get_prefix(pclc);
345 	if (hdr->version == SMC_V1) {
346 		if (hdr->typev1 == SMC_TYPE_N)
347 			return false;
348 		if (ntohs(hdr->length) !=
349 			sizeof(*pclc) + ntohs(pclc->iparea_offset) +
350 			sizeof(*pclc_prfx) +
351 			pclc_prfx->ipv6_prefixes_cnt *
352 				sizeof(struct smc_clc_ipv6_prefix) +
353 			sizeof(struct smc_clc_msg_trail))
354 			return false;
355 	} else {
356 		if (ntohs(hdr->length) !=
357 			sizeof(*pclc) +
358 			sizeof(struct smc_clc_msg_smcd) +
359 			(hdr->typev1 != SMC_TYPE_N ?
360 				sizeof(*pclc_prfx) +
361 				pclc_prfx->ipv6_prefixes_cnt *
362 				sizeof(struct smc_clc_ipv6_prefix) : 0) +
363 			(hdr->typev2 != SMC_TYPE_N ?
364 				sizeof(*v2_ext) +
365 				v2_ext->hdr.eid_cnt * SMC_MAX_EID_LEN : 0) +
366 			(smcd_indicated(hdr->typev2) ?
367 				sizeof(*smcd_v2_ext) + v2_ext->hdr.ism_gid_cnt *
368 					sizeof(struct smc_clc_smcd_gid_chid) :
369 				0) +
370 			sizeof(struct smc_clc_msg_trail))
371 			return false;
372 	}
373 	return true;
374 }
375 
376 /* check arriving CLC accept or confirm */
377 static bool
378 smc_clc_msg_acc_conf_valid(struct smc_clc_msg_accept_confirm_v2 *clc_v2)
379 {
380 	struct smc_clc_msg_hdr *hdr = &clc_v2->hdr;
381 
382 	if (hdr->typev1 != SMC_TYPE_R && hdr->typev1 != SMC_TYPE_D)
383 		return false;
384 	if (hdr->version == SMC_V1) {
385 		if ((hdr->typev1 == SMC_TYPE_R &&
386 		     ntohs(hdr->length) != SMCR_CLC_ACCEPT_CONFIRM_LEN) ||
387 		    (hdr->typev1 == SMC_TYPE_D &&
388 		     ntohs(hdr->length) != SMCD_CLC_ACCEPT_CONFIRM_LEN))
389 			return false;
390 	} else {
391 		if (hdr->typev1 == SMC_TYPE_D &&
392 		    ntohs(hdr->length) != SMCD_CLC_ACCEPT_CONFIRM_LEN_V2 &&
393 		    (ntohs(hdr->length) != SMCD_CLC_ACCEPT_CONFIRM_LEN_V2 +
394 				sizeof(struct smc_clc_first_contact_ext)))
395 			return false;
396 		if (hdr->typev1 == SMC_TYPE_R &&
397 		    ntohs(hdr->length) < SMCR_CLC_ACCEPT_CONFIRM_LEN_V2)
398 			return false;
399 	}
400 	return true;
401 }
402 
403 /* check arriving CLC decline */
404 static bool
405 smc_clc_msg_decl_valid(struct smc_clc_msg_decline *dclc)
406 {
407 	struct smc_clc_msg_hdr *hdr = &dclc->hdr;
408 
409 	if (hdr->typev1 != SMC_TYPE_R && hdr->typev1 != SMC_TYPE_D)
410 		return false;
411 	if (hdr->version == SMC_V1) {
412 		if (ntohs(hdr->length) != sizeof(struct smc_clc_msg_decline))
413 			return false;
414 	} else {
415 		if (ntohs(hdr->length) != sizeof(struct smc_clc_msg_decline_v2))
416 			return false;
417 	}
418 	return true;
419 }
420 
421 static void smc_clc_fill_fce(struct smc_clc_first_contact_ext *fce, int *len)
422 {
423 	memset(fce, 0, sizeof(*fce));
424 	fce->os_type = SMC_CLC_OS_LINUX;
425 	fce->release = SMC_RELEASE;
426 	memcpy(fce->hostname, smc_hostname, sizeof(smc_hostname));
427 	(*len) += sizeof(*fce);
428 }
429 
430 /* check if received message has a correct header length and contains valid
431  * heading and trailing eyecatchers
432  */
433 static bool smc_clc_msg_hdr_valid(struct smc_clc_msg_hdr *clcm, bool check_trl)
434 {
435 	struct smc_clc_msg_accept_confirm_v2 *clc_v2;
436 	struct smc_clc_msg_proposal *pclc;
437 	struct smc_clc_msg_decline *dclc;
438 	struct smc_clc_msg_trail *trl;
439 
440 	if (memcmp(clcm->eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER)) &&
441 	    memcmp(clcm->eyecatcher, SMCD_EYECATCHER, sizeof(SMCD_EYECATCHER)))
442 		return false;
443 	switch (clcm->type) {
444 	case SMC_CLC_PROPOSAL:
445 		pclc = (struct smc_clc_msg_proposal *)clcm;
446 		if (!smc_clc_msg_prop_valid(pclc))
447 			return false;
448 		trl = (struct smc_clc_msg_trail *)
449 			((u8 *)pclc + ntohs(pclc->hdr.length) - sizeof(*trl));
450 		break;
451 	case SMC_CLC_ACCEPT:
452 	case SMC_CLC_CONFIRM:
453 		clc_v2 = (struct smc_clc_msg_accept_confirm_v2 *)clcm;
454 		if (!smc_clc_msg_acc_conf_valid(clc_v2))
455 			return false;
456 		trl = (struct smc_clc_msg_trail *)
457 			((u8 *)clc_v2 + ntohs(clc_v2->hdr.length) -
458 							sizeof(*trl));
459 		break;
460 	case SMC_CLC_DECLINE:
461 		dclc = (struct smc_clc_msg_decline *)clcm;
462 		if (!smc_clc_msg_decl_valid(dclc))
463 			return false;
464 		check_trl = false;
465 		break;
466 	default:
467 		return false;
468 	}
469 	if (check_trl &&
470 	    memcmp(trl->eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER)) &&
471 	    memcmp(trl->eyecatcher, SMCD_EYECATCHER, sizeof(SMCD_EYECATCHER)))
472 		return false;
473 	return true;
474 }
475 
476 /* find ipv4 addr on device and get the prefix len, fill CLC proposal msg */
477 static int smc_clc_prfx_set4_rcu(struct dst_entry *dst, __be32 ipv4,
478 				 struct smc_clc_msg_proposal_prefix *prop)
479 {
480 	struct in_device *in_dev = __in_dev_get_rcu(dst->dev);
481 	const struct in_ifaddr *ifa;
482 
483 	if (!in_dev)
484 		return -ENODEV;
485 
486 	in_dev_for_each_ifa_rcu(ifa, in_dev) {
487 		if (!inet_ifa_match(ipv4, ifa))
488 			continue;
489 		prop->prefix_len = inet_mask_len(ifa->ifa_mask);
490 		prop->outgoing_subnet = ifa->ifa_address & ifa->ifa_mask;
491 		/* prop->ipv6_prefixes_cnt = 0; already done by memset before */
492 		return 0;
493 	}
494 	return -ENOENT;
495 }
496 
497 /* fill CLC proposal msg with ipv6 prefixes from device */
498 static int smc_clc_prfx_set6_rcu(struct dst_entry *dst,
499 				 struct smc_clc_msg_proposal_prefix *prop,
500 				 struct smc_clc_ipv6_prefix *ipv6_prfx)
501 {
502 #if IS_ENABLED(CONFIG_IPV6)
503 	struct inet6_dev *in6_dev = __in6_dev_get(dst->dev);
504 	struct inet6_ifaddr *ifa;
505 	int cnt = 0;
506 
507 	if (!in6_dev)
508 		return -ENODEV;
509 	/* use a maximum of 8 IPv6 prefixes from device */
510 	list_for_each_entry(ifa, &in6_dev->addr_list, if_list) {
511 		if (ipv6_addr_type(&ifa->addr) & IPV6_ADDR_LINKLOCAL)
512 			continue;
513 		ipv6_addr_prefix(&ipv6_prfx[cnt].prefix,
514 				 &ifa->addr, ifa->prefix_len);
515 		ipv6_prfx[cnt].prefix_len = ifa->prefix_len;
516 		cnt++;
517 		if (cnt == SMC_CLC_MAX_V6_PREFIX)
518 			break;
519 	}
520 	prop->ipv6_prefixes_cnt = cnt;
521 	if (cnt)
522 		return 0;
523 #endif
524 	return -ENOENT;
525 }
526 
527 /* retrieve and set prefixes in CLC proposal msg */
528 static int smc_clc_prfx_set(struct socket *clcsock,
529 			    struct smc_clc_msg_proposal_prefix *prop,
530 			    struct smc_clc_ipv6_prefix *ipv6_prfx)
531 {
532 	struct dst_entry *dst = sk_dst_get(clcsock->sk);
533 	struct sockaddr_storage addrs;
534 	struct sockaddr_in6 *addr6;
535 	struct sockaddr_in *addr;
536 	int rc = -ENOENT;
537 
538 	if (!dst) {
539 		rc = -ENOTCONN;
540 		goto out;
541 	}
542 	if (!dst->dev) {
543 		rc = -ENODEV;
544 		goto out_rel;
545 	}
546 	/* get address to which the internal TCP socket is bound */
547 	if (kernel_getsockname(clcsock, (struct sockaddr *)&addrs) < 0)
548 		goto out_rel;
549 	/* analyze IP specific data of net_device belonging to TCP socket */
550 	addr6 = (struct sockaddr_in6 *)&addrs;
551 	rcu_read_lock();
552 	if (addrs.ss_family == PF_INET) {
553 		/* IPv4 */
554 		addr = (struct sockaddr_in *)&addrs;
555 		rc = smc_clc_prfx_set4_rcu(dst, addr->sin_addr.s_addr, prop);
556 	} else if (ipv6_addr_v4mapped(&addr6->sin6_addr)) {
557 		/* mapped IPv4 address - peer is IPv4 only */
558 		rc = smc_clc_prfx_set4_rcu(dst, addr6->sin6_addr.s6_addr32[3],
559 					   prop);
560 	} else {
561 		/* IPv6 */
562 		rc = smc_clc_prfx_set6_rcu(dst, prop, ipv6_prfx);
563 	}
564 	rcu_read_unlock();
565 out_rel:
566 	dst_release(dst);
567 out:
568 	return rc;
569 }
570 
571 /* match ipv4 addrs of dev against addr in CLC proposal */
572 static int smc_clc_prfx_match4_rcu(struct net_device *dev,
573 				   struct smc_clc_msg_proposal_prefix *prop)
574 {
575 	struct in_device *in_dev = __in_dev_get_rcu(dev);
576 	const struct in_ifaddr *ifa;
577 
578 	if (!in_dev)
579 		return -ENODEV;
580 	in_dev_for_each_ifa_rcu(ifa, in_dev) {
581 		if (prop->prefix_len == inet_mask_len(ifa->ifa_mask) &&
582 		    inet_ifa_match(prop->outgoing_subnet, ifa))
583 			return 0;
584 	}
585 
586 	return -ENOENT;
587 }
588 
589 /* match ipv6 addrs of dev against addrs in CLC proposal */
590 static int smc_clc_prfx_match6_rcu(struct net_device *dev,
591 				   struct smc_clc_msg_proposal_prefix *prop)
592 {
593 #if IS_ENABLED(CONFIG_IPV6)
594 	struct inet6_dev *in6_dev = __in6_dev_get(dev);
595 	struct smc_clc_ipv6_prefix *ipv6_prfx;
596 	struct inet6_ifaddr *ifa;
597 	int i, max;
598 
599 	if (!in6_dev)
600 		return -ENODEV;
601 	/* ipv6 prefix list starts behind smc_clc_msg_proposal_prefix */
602 	ipv6_prfx = (struct smc_clc_ipv6_prefix *)((u8 *)prop + sizeof(*prop));
603 	max = min_t(u8, prop->ipv6_prefixes_cnt, SMC_CLC_MAX_V6_PREFIX);
604 	list_for_each_entry(ifa, &in6_dev->addr_list, if_list) {
605 		if (ipv6_addr_type(&ifa->addr) & IPV6_ADDR_LINKLOCAL)
606 			continue;
607 		for (i = 0; i < max; i++) {
608 			if (ifa->prefix_len == ipv6_prfx[i].prefix_len &&
609 			    ipv6_prefix_equal(&ifa->addr, &ipv6_prfx[i].prefix,
610 					      ifa->prefix_len))
611 				return 0;
612 		}
613 	}
614 #endif
615 	return -ENOENT;
616 }
617 
618 /* check if proposed prefixes match one of our device prefixes */
619 int smc_clc_prfx_match(struct socket *clcsock,
620 		       struct smc_clc_msg_proposal_prefix *prop)
621 {
622 	struct dst_entry *dst = sk_dst_get(clcsock->sk);
623 	int rc;
624 
625 	if (!dst) {
626 		rc = -ENOTCONN;
627 		goto out;
628 	}
629 	if (!dst->dev) {
630 		rc = -ENODEV;
631 		goto out_rel;
632 	}
633 	rcu_read_lock();
634 	if (!prop->ipv6_prefixes_cnt)
635 		rc = smc_clc_prfx_match4_rcu(dst->dev, prop);
636 	else
637 		rc = smc_clc_prfx_match6_rcu(dst->dev, prop);
638 	rcu_read_unlock();
639 out_rel:
640 	dst_release(dst);
641 out:
642 	return rc;
643 }
644 
645 /* Wait for data on the tcp-socket, analyze received data
646  * Returns:
647  * 0 if success and it was not a decline that we received.
648  * SMC_CLC_DECL_REPLY if decline received for fallback w/o another decl send.
649  * clcsock error, -EINTR, -ECONNRESET, -EPROTO otherwise.
650  */
651 int smc_clc_wait_msg(struct smc_sock *smc, void *buf, int buflen,
652 		     u8 expected_type, unsigned long timeout)
653 {
654 	long rcvtimeo = smc->clcsock->sk->sk_rcvtimeo;
655 	struct sock *clc_sk = smc->clcsock->sk;
656 	struct smc_clc_msg_hdr *clcm = buf;
657 	struct msghdr msg = {NULL, 0};
658 	int reason_code = 0;
659 	struct kvec vec = {buf, buflen};
660 	int len, datlen, recvlen;
661 	bool check_trl = true;
662 	int krflags;
663 
664 	/* peek the first few bytes to determine length of data to receive
665 	 * so we don't consume any subsequent CLC message or payload data
666 	 * in the TCP byte stream
667 	 */
668 	/*
669 	 * Caller must make sure that buflen is no less than
670 	 * sizeof(struct smc_clc_msg_hdr)
671 	 */
672 	krflags = MSG_PEEK | MSG_WAITALL;
673 	clc_sk->sk_rcvtimeo = timeout;
674 	iov_iter_kvec(&msg.msg_iter, READ, &vec, 1,
675 			sizeof(struct smc_clc_msg_hdr));
676 	len = sock_recvmsg(smc->clcsock, &msg, krflags);
677 	if (signal_pending(current)) {
678 		reason_code = -EINTR;
679 		clc_sk->sk_err = EINTR;
680 		smc->sk.sk_err = EINTR;
681 		goto out;
682 	}
683 	if (clc_sk->sk_err) {
684 		reason_code = -clc_sk->sk_err;
685 		if (clc_sk->sk_err == EAGAIN &&
686 		    expected_type == SMC_CLC_DECLINE)
687 			clc_sk->sk_err = 0; /* reset for fallback usage */
688 		else
689 			smc->sk.sk_err = clc_sk->sk_err;
690 		goto out;
691 	}
692 	if (!len) { /* peer has performed orderly shutdown */
693 		smc->sk.sk_err = ECONNRESET;
694 		reason_code = -ECONNRESET;
695 		goto out;
696 	}
697 	if (len < 0) {
698 		if (len != -EAGAIN || expected_type != SMC_CLC_DECLINE)
699 			smc->sk.sk_err = -len;
700 		reason_code = len;
701 		goto out;
702 	}
703 	datlen = ntohs(clcm->length);
704 	if ((len < sizeof(struct smc_clc_msg_hdr)) ||
705 	    (clcm->version < SMC_V1) ||
706 	    ((clcm->type != SMC_CLC_DECLINE) &&
707 	     (clcm->type != expected_type))) {
708 		smc->sk.sk_err = EPROTO;
709 		reason_code = -EPROTO;
710 		goto out;
711 	}
712 
713 	/* receive the complete CLC message */
714 	memset(&msg, 0, sizeof(struct msghdr));
715 	if (datlen > buflen) {
716 		check_trl = false;
717 		recvlen = buflen;
718 	} else {
719 		recvlen = datlen;
720 	}
721 	iov_iter_kvec(&msg.msg_iter, READ, &vec, 1, recvlen);
722 	krflags = MSG_WAITALL;
723 	len = sock_recvmsg(smc->clcsock, &msg, krflags);
724 	if (len < recvlen || !smc_clc_msg_hdr_valid(clcm, check_trl)) {
725 		smc->sk.sk_err = EPROTO;
726 		reason_code = -EPROTO;
727 		goto out;
728 	}
729 	datlen -= len;
730 	while (datlen) {
731 		u8 tmp[SMC_CLC_RECV_BUF_LEN];
732 
733 		vec.iov_base = &tmp;
734 		vec.iov_len = SMC_CLC_RECV_BUF_LEN;
735 		/* receive remaining proposal message */
736 		recvlen = datlen > SMC_CLC_RECV_BUF_LEN ?
737 						SMC_CLC_RECV_BUF_LEN : datlen;
738 		iov_iter_kvec(&msg.msg_iter, READ, &vec, 1, recvlen);
739 		len = sock_recvmsg(smc->clcsock, &msg, krflags);
740 		datlen -= len;
741 	}
742 	if (clcm->type == SMC_CLC_DECLINE) {
743 		struct smc_clc_msg_decline *dclc;
744 
745 		dclc = (struct smc_clc_msg_decline *)clcm;
746 		reason_code = SMC_CLC_DECL_PEERDECL;
747 		smc->peer_diagnosis = ntohl(dclc->peer_diagnosis);
748 		if (((struct smc_clc_msg_decline *)buf)->hdr.typev2 &
749 						SMC_FIRST_CONTACT_MASK) {
750 			smc->conn.lgr->sync_err = 1;
751 			smc_lgr_terminate_sched(smc->conn.lgr);
752 		}
753 	}
754 
755 out:
756 	clc_sk->sk_rcvtimeo = rcvtimeo;
757 	return reason_code;
758 }
759 
760 /* send CLC DECLINE message across internal TCP socket */
761 int smc_clc_send_decline(struct smc_sock *smc, u32 peer_diag_info, u8 version)
762 {
763 	struct smc_clc_msg_decline *dclc_v1;
764 	struct smc_clc_msg_decline_v2 dclc;
765 	struct msghdr msg;
766 	int len, send_len;
767 	struct kvec vec;
768 
769 	dclc_v1 = (struct smc_clc_msg_decline *)&dclc;
770 	memset(&dclc, 0, sizeof(dclc));
771 	memcpy(dclc.hdr.eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
772 	dclc.hdr.type = SMC_CLC_DECLINE;
773 	dclc.hdr.version = version;
774 	dclc.os_type = version == SMC_V1 ? 0 : SMC_CLC_OS_LINUX;
775 	dclc.hdr.typev2 = (peer_diag_info == SMC_CLC_DECL_SYNCERR) ?
776 						SMC_FIRST_CONTACT_MASK : 0;
777 	if ((!smc->conn.lgr || !smc->conn.lgr->is_smcd) &&
778 	    smc_ib_is_valid_local_systemid())
779 		memcpy(dclc.id_for_peer, local_systemid,
780 		       sizeof(local_systemid));
781 	dclc.peer_diagnosis = htonl(peer_diag_info);
782 	if (version == SMC_V1) {
783 		memcpy(dclc_v1->trl.eyecatcher, SMC_EYECATCHER,
784 		       sizeof(SMC_EYECATCHER));
785 		send_len = sizeof(*dclc_v1);
786 	} else {
787 		memcpy(dclc.trl.eyecatcher, SMC_EYECATCHER,
788 		       sizeof(SMC_EYECATCHER));
789 		send_len = sizeof(dclc);
790 	}
791 	dclc.hdr.length = htons(send_len);
792 
793 	memset(&msg, 0, sizeof(msg));
794 	vec.iov_base = &dclc;
795 	vec.iov_len = send_len;
796 	len = kernel_sendmsg(smc->clcsock, &msg, &vec, 1, send_len);
797 	if (len < 0 || len < send_len)
798 		len = -EPROTO;
799 	return len > 0 ? 0 : len;
800 }
801 
802 /* send CLC PROPOSAL message across internal TCP socket */
803 int smc_clc_send_proposal(struct smc_sock *smc, struct smc_init_info *ini)
804 {
805 	struct smc_clc_smcd_v2_extension *smcd_v2_ext;
806 	struct smc_clc_msg_proposal_prefix *pclc_prfx;
807 	struct smc_clc_msg_proposal *pclc_base;
808 	struct smc_clc_smcd_gid_chid *gidchids;
809 	struct smc_clc_msg_proposal_area *pclc;
810 	struct smc_clc_ipv6_prefix *ipv6_prfx;
811 	struct smc_clc_v2_extension *v2_ext;
812 	struct smc_clc_msg_smcd *pclc_smcd;
813 	struct smc_clc_msg_trail *trl;
814 	int len, i, plen, rc;
815 	int reason_code = 0;
816 	struct kvec vec[8];
817 	struct msghdr msg;
818 
819 	pclc = kzalloc(sizeof(*pclc), GFP_KERNEL);
820 	if (!pclc)
821 		return -ENOMEM;
822 
823 	pclc_base = &pclc->pclc_base;
824 	pclc_smcd = &pclc->pclc_smcd;
825 	pclc_prfx = &pclc->pclc_prfx;
826 	ipv6_prfx = pclc->pclc_prfx_ipv6;
827 	v2_ext = &pclc->pclc_v2_ext;
828 	smcd_v2_ext = &pclc->pclc_smcd_v2_ext;
829 	gidchids = pclc->pclc_gidchids;
830 	trl = &pclc->pclc_trl;
831 
832 	pclc_base->hdr.version = SMC_V2;
833 	pclc_base->hdr.typev1 = ini->smc_type_v1;
834 	pclc_base->hdr.typev2 = ini->smc_type_v2;
835 	plen = sizeof(*pclc_base) + sizeof(*pclc_smcd) + sizeof(*trl);
836 
837 	/* retrieve ip prefixes for CLC proposal msg */
838 	if (ini->smc_type_v1 != SMC_TYPE_N) {
839 		rc = smc_clc_prfx_set(smc->clcsock, pclc_prfx, ipv6_prfx);
840 		if (rc) {
841 			if (ini->smc_type_v2 == SMC_TYPE_N) {
842 				kfree(pclc);
843 				return SMC_CLC_DECL_CNFERR;
844 			}
845 			pclc_base->hdr.typev1 = SMC_TYPE_N;
846 		} else {
847 			pclc_base->iparea_offset = htons(sizeof(*pclc_smcd));
848 			plen += sizeof(*pclc_prfx) +
849 					pclc_prfx->ipv6_prefixes_cnt *
850 					sizeof(ipv6_prfx[0]);
851 		}
852 	}
853 
854 	/* build SMC Proposal CLC message */
855 	memcpy(pclc_base->hdr.eyecatcher, SMC_EYECATCHER,
856 	       sizeof(SMC_EYECATCHER));
857 	pclc_base->hdr.type = SMC_CLC_PROPOSAL;
858 	if (smcr_indicated(ini->smc_type_v1)) {
859 		/* add SMC-R specifics */
860 		memcpy(pclc_base->lcl.id_for_peer, local_systemid,
861 		       sizeof(local_systemid));
862 		memcpy(pclc_base->lcl.gid, ini->ib_gid, SMC_GID_SIZE);
863 		memcpy(pclc_base->lcl.mac, &ini->ib_dev->mac[ini->ib_port - 1],
864 		       ETH_ALEN);
865 	}
866 	if (smcd_indicated(ini->smc_type_v1)) {
867 		/* add SMC-D specifics */
868 		if (ini->ism_dev[0]) {
869 			pclc_smcd->ism.gid = htonll(ini->ism_dev[0]->local_gid);
870 			pclc_smcd->ism.chid =
871 				htons(smc_ism_get_chid(ini->ism_dev[0]));
872 		}
873 	}
874 	if (ini->smc_type_v2 == SMC_TYPE_N) {
875 		pclc_smcd->v2_ext_offset = 0;
876 	} else {
877 		struct smc_clc_eid_entry *ueident;
878 		u16 v2_ext_offset;
879 
880 		v2_ext->hdr.flag.release = SMC_RELEASE;
881 		v2_ext_offset = sizeof(*pclc_smcd) -
882 			offsetofend(struct smc_clc_msg_smcd, v2_ext_offset);
883 		if (ini->smc_type_v1 != SMC_TYPE_N)
884 			v2_ext_offset += sizeof(*pclc_prfx) +
885 						pclc_prfx->ipv6_prefixes_cnt *
886 						sizeof(ipv6_prfx[0]);
887 		pclc_smcd->v2_ext_offset = htons(v2_ext_offset);
888 		plen += sizeof(*v2_ext);
889 
890 		read_lock(&smc_clc_eid_table.lock);
891 		v2_ext->hdr.eid_cnt = smc_clc_eid_table.ueid_cnt;
892 		plen += smc_clc_eid_table.ueid_cnt * SMC_MAX_EID_LEN;
893 		i = 0;
894 		list_for_each_entry(ueident, &smc_clc_eid_table.list, list) {
895 			memcpy(v2_ext->user_eids[i++], ueident->eid,
896 			       sizeof(ueident->eid));
897 		}
898 		read_unlock(&smc_clc_eid_table.lock);
899 	}
900 	if (smcd_indicated(ini->smc_type_v2)) {
901 		u8 *eid = NULL;
902 
903 		v2_ext->hdr.flag.seid = smc_clc_eid_table.seid_enabled;
904 		v2_ext->hdr.ism_gid_cnt = ini->ism_offered_cnt;
905 		v2_ext->hdr.smcd_v2_ext_offset = htons(sizeof(*v2_ext) -
906 				offsetofend(struct smc_clnt_opts_area_hdr,
907 					    smcd_v2_ext_offset) +
908 				v2_ext->hdr.eid_cnt * SMC_MAX_EID_LEN);
909 		smc_ism_get_system_eid(&eid);
910 		if (eid && v2_ext->hdr.flag.seid)
911 			memcpy(smcd_v2_ext->system_eid, eid, SMC_MAX_EID_LEN);
912 		plen += sizeof(*smcd_v2_ext);
913 		if (ini->ism_offered_cnt) {
914 			for (i = 1; i <= ini->ism_offered_cnt; i++) {
915 				gidchids[i - 1].gid =
916 					htonll(ini->ism_dev[i]->local_gid);
917 				gidchids[i - 1].chid =
918 					htons(smc_ism_get_chid(ini->ism_dev[i]));
919 			}
920 			plen += ini->ism_offered_cnt *
921 				sizeof(struct smc_clc_smcd_gid_chid);
922 		}
923 	}
924 	if (smcr_indicated(ini->smc_type_v2))
925 		memcpy(v2_ext->roce, ini->smcrv2.ib_gid_v2, SMC_GID_SIZE);
926 
927 	pclc_base->hdr.length = htons(plen);
928 	memcpy(trl->eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
929 
930 	/* send SMC Proposal CLC message */
931 	memset(&msg, 0, sizeof(msg));
932 	i = 0;
933 	vec[i].iov_base = pclc_base;
934 	vec[i++].iov_len = sizeof(*pclc_base);
935 	vec[i].iov_base = pclc_smcd;
936 	vec[i++].iov_len = sizeof(*pclc_smcd);
937 	if (ini->smc_type_v1 != SMC_TYPE_N) {
938 		vec[i].iov_base = pclc_prfx;
939 		vec[i++].iov_len = sizeof(*pclc_prfx);
940 		if (pclc_prfx->ipv6_prefixes_cnt > 0) {
941 			vec[i].iov_base = ipv6_prfx;
942 			vec[i++].iov_len = pclc_prfx->ipv6_prefixes_cnt *
943 					   sizeof(ipv6_prfx[0]);
944 		}
945 	}
946 	if (ini->smc_type_v2 != SMC_TYPE_N) {
947 		vec[i].iov_base = v2_ext;
948 		vec[i++].iov_len = sizeof(*v2_ext) +
949 				   (v2_ext->hdr.eid_cnt * SMC_MAX_EID_LEN);
950 		if (smcd_indicated(ini->smc_type_v2)) {
951 			vec[i].iov_base = smcd_v2_ext;
952 			vec[i++].iov_len = sizeof(*smcd_v2_ext);
953 			if (ini->ism_offered_cnt) {
954 				vec[i].iov_base = gidchids;
955 				vec[i++].iov_len = ini->ism_offered_cnt *
956 					sizeof(struct smc_clc_smcd_gid_chid);
957 			}
958 		}
959 	}
960 	vec[i].iov_base = trl;
961 	vec[i++].iov_len = sizeof(*trl);
962 	/* due to the few bytes needed for clc-handshake this cannot block */
963 	len = kernel_sendmsg(smc->clcsock, &msg, vec, i, plen);
964 	if (len < 0) {
965 		smc->sk.sk_err = smc->clcsock->sk->sk_err;
966 		reason_code = -smc->sk.sk_err;
967 	} else if (len < ntohs(pclc_base->hdr.length)) {
968 		reason_code = -ENETUNREACH;
969 		smc->sk.sk_err = -reason_code;
970 	}
971 
972 	kfree(pclc);
973 	return reason_code;
974 }
975 
976 /* build and send CLC CONFIRM / ACCEPT message */
977 static int smc_clc_send_confirm_accept(struct smc_sock *smc,
978 				       struct smc_clc_msg_accept_confirm_v2 *clc_v2,
979 				       int first_contact, u8 version,
980 				       u8 *eid, struct smc_init_info *ini)
981 {
982 	struct smc_connection *conn = &smc->conn;
983 	struct smc_clc_msg_accept_confirm *clc;
984 	struct smc_clc_first_contact_ext fce;
985 	struct smc_clc_fce_gid_ext gle;
986 	struct smc_clc_msg_trail trl;
987 	struct kvec vec[5];
988 	struct msghdr msg;
989 	int i, len;
990 
991 	/* send SMC Confirm CLC msg */
992 	clc = (struct smc_clc_msg_accept_confirm *)clc_v2;
993 	clc->hdr.version = version;	/* SMC version */
994 	if (first_contact)
995 		clc->hdr.typev2 |= SMC_FIRST_CONTACT_MASK;
996 	if (conn->lgr->is_smcd) {
997 		/* SMC-D specific settings */
998 		memcpy(clc->hdr.eyecatcher, SMCD_EYECATCHER,
999 		       sizeof(SMCD_EYECATCHER));
1000 		clc->hdr.typev1 = SMC_TYPE_D;
1001 		clc->d0.gid = conn->lgr->smcd->local_gid;
1002 		clc->d0.token = conn->rmb_desc->token;
1003 		clc->d0.dmbe_size = conn->rmbe_size_short;
1004 		clc->d0.dmbe_idx = 0;
1005 		memcpy(&clc->d0.linkid, conn->lgr->id, SMC_LGR_ID_SIZE);
1006 		if (version == SMC_V1) {
1007 			clc->hdr.length = htons(SMCD_CLC_ACCEPT_CONFIRM_LEN);
1008 		} else {
1009 			clc_v2->d1.chid =
1010 				htons(smc_ism_get_chid(conn->lgr->smcd));
1011 			if (eid && eid[0])
1012 				memcpy(clc_v2->d1.eid, eid, SMC_MAX_EID_LEN);
1013 			len = SMCD_CLC_ACCEPT_CONFIRM_LEN_V2;
1014 			if (first_contact)
1015 				smc_clc_fill_fce(&fce, &len);
1016 			clc_v2->hdr.length = htons(len);
1017 		}
1018 		memcpy(trl.eyecatcher, SMCD_EYECATCHER,
1019 		       sizeof(SMCD_EYECATCHER));
1020 	} else {
1021 		struct smc_link *link = conn->lnk;
1022 
1023 		/* SMC-R specific settings */
1024 		link = conn->lnk;
1025 		memcpy(clc->hdr.eyecatcher, SMC_EYECATCHER,
1026 		       sizeof(SMC_EYECATCHER));
1027 		clc->hdr.typev1 = SMC_TYPE_R;
1028 		clc->hdr.length = htons(SMCR_CLC_ACCEPT_CONFIRM_LEN);
1029 		memcpy(clc->r0.lcl.id_for_peer, local_systemid,
1030 		       sizeof(local_systemid));
1031 		memcpy(&clc->r0.lcl.gid, link->gid, SMC_GID_SIZE);
1032 		memcpy(&clc->r0.lcl.mac, &link->smcibdev->mac[link->ibport - 1],
1033 		       ETH_ALEN);
1034 		hton24(clc->r0.qpn, link->roce_qp->qp_num);
1035 		clc->r0.rmb_rkey =
1036 			htonl(conn->rmb_desc->mr_rx[link->link_idx]->rkey);
1037 		clc->r0.rmbe_idx = 1; /* for now: 1 RMB = 1 RMBE */
1038 		clc->r0.rmbe_alert_token = htonl(conn->alert_token_local);
1039 		switch (clc->hdr.type) {
1040 		case SMC_CLC_ACCEPT:
1041 			clc->r0.qp_mtu = link->path_mtu;
1042 			break;
1043 		case SMC_CLC_CONFIRM:
1044 			clc->r0.qp_mtu = min(link->path_mtu, link->peer_mtu);
1045 			break;
1046 		}
1047 		clc->r0.rmbe_size = conn->rmbe_size_short;
1048 		clc->r0.rmb_dma_addr = cpu_to_be64((u64)sg_dma_address
1049 				(conn->rmb_desc->sgt[link->link_idx].sgl));
1050 		hton24(clc->r0.psn, link->psn_initial);
1051 		if (version == SMC_V1) {
1052 			clc->hdr.length = htons(SMCR_CLC_ACCEPT_CONFIRM_LEN);
1053 		} else {
1054 			if (eid && eid[0])
1055 				memcpy(clc_v2->r1.eid, eid, SMC_MAX_EID_LEN);
1056 			len = SMCR_CLC_ACCEPT_CONFIRM_LEN_V2;
1057 			if (first_contact) {
1058 				smc_clc_fill_fce(&fce, &len);
1059 				fce.v2_direct = !link->lgr->uses_gateway;
1060 				memset(&gle, 0, sizeof(gle));
1061 				if (ini && clc->hdr.type == SMC_CLC_CONFIRM) {
1062 					gle.gid_cnt = ini->smcrv2.gidlist.len;
1063 					len += sizeof(gle);
1064 					len += gle.gid_cnt * sizeof(gle.gid[0]);
1065 				} else {
1066 					len += sizeof(gle.reserved);
1067 				}
1068 			}
1069 			clc_v2->hdr.length = htons(len);
1070 		}
1071 		memcpy(trl.eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
1072 	}
1073 
1074 	memset(&msg, 0, sizeof(msg));
1075 	i = 0;
1076 	vec[i].iov_base = clc_v2;
1077 	if (version > SMC_V1)
1078 		vec[i++].iov_len = (clc->hdr.typev1 == SMC_TYPE_D ?
1079 					SMCD_CLC_ACCEPT_CONFIRM_LEN_V2 :
1080 					SMCR_CLC_ACCEPT_CONFIRM_LEN_V2) -
1081 				   sizeof(trl);
1082 	else
1083 		vec[i++].iov_len = (clc->hdr.typev1 == SMC_TYPE_D ?
1084 						SMCD_CLC_ACCEPT_CONFIRM_LEN :
1085 						SMCR_CLC_ACCEPT_CONFIRM_LEN) -
1086 				   sizeof(trl);
1087 	if (version > SMC_V1 && first_contact) {
1088 		vec[i].iov_base = &fce;
1089 		vec[i++].iov_len = sizeof(fce);
1090 		if (!conn->lgr->is_smcd) {
1091 			if (clc->hdr.type == SMC_CLC_CONFIRM) {
1092 				vec[i].iov_base = &gle;
1093 				vec[i++].iov_len = sizeof(gle);
1094 				vec[i].iov_base = &ini->smcrv2.gidlist.list;
1095 				vec[i++].iov_len = gle.gid_cnt *
1096 						   sizeof(gle.gid[0]);
1097 			} else {
1098 				vec[i].iov_base = &gle.reserved;
1099 				vec[i++].iov_len = sizeof(gle.reserved);
1100 			}
1101 		}
1102 	}
1103 	vec[i].iov_base = &trl;
1104 	vec[i++].iov_len = sizeof(trl);
1105 	return kernel_sendmsg(smc->clcsock, &msg, vec, 1,
1106 			      ntohs(clc->hdr.length));
1107 }
1108 
1109 /* send CLC CONFIRM message across internal TCP socket */
1110 int smc_clc_send_confirm(struct smc_sock *smc, bool clnt_first_contact,
1111 			 u8 version, u8 *eid, struct smc_init_info *ini)
1112 {
1113 	struct smc_clc_msg_accept_confirm_v2 cclc_v2;
1114 	int reason_code = 0;
1115 	int len;
1116 
1117 	/* send SMC Confirm CLC msg */
1118 	memset(&cclc_v2, 0, sizeof(cclc_v2));
1119 	cclc_v2.hdr.type = SMC_CLC_CONFIRM;
1120 	len = smc_clc_send_confirm_accept(smc, &cclc_v2, clnt_first_contact,
1121 					  version, eid, ini);
1122 	if (len < ntohs(cclc_v2.hdr.length)) {
1123 		if (len >= 0) {
1124 			reason_code = -ENETUNREACH;
1125 			smc->sk.sk_err = -reason_code;
1126 		} else {
1127 			smc->sk.sk_err = smc->clcsock->sk->sk_err;
1128 			reason_code = -smc->sk.sk_err;
1129 		}
1130 	}
1131 	return reason_code;
1132 }
1133 
1134 /* send CLC ACCEPT message across internal TCP socket */
1135 int smc_clc_send_accept(struct smc_sock *new_smc, bool srv_first_contact,
1136 			u8 version, u8 *negotiated_eid)
1137 {
1138 	struct smc_clc_msg_accept_confirm_v2 aclc_v2;
1139 	int len;
1140 
1141 	memset(&aclc_v2, 0, sizeof(aclc_v2));
1142 	aclc_v2.hdr.type = SMC_CLC_ACCEPT;
1143 	len = smc_clc_send_confirm_accept(new_smc, &aclc_v2, srv_first_contact,
1144 					  version, negotiated_eid, NULL);
1145 	if (len < ntohs(aclc_v2.hdr.length))
1146 		len = len >= 0 ? -EPROTO : -new_smc->clcsock->sk->sk_err;
1147 
1148 	return len > 0 ? 0 : len;
1149 }
1150 
1151 void smc_clc_get_hostname(u8 **host)
1152 {
1153 	*host = &smc_hostname[0];
1154 }
1155 
1156 void __init smc_clc_init(void)
1157 {
1158 	struct new_utsname *u;
1159 
1160 	memset(smc_hostname, _S, sizeof(smc_hostname)); /* ASCII blanks */
1161 	u = utsname();
1162 	memcpy(smc_hostname, u->nodename,
1163 	       min_t(size_t, strlen(u->nodename), sizeof(smc_hostname)));
1164 
1165 	INIT_LIST_HEAD(&smc_clc_eid_table.list);
1166 	rwlock_init(&smc_clc_eid_table.lock);
1167 	smc_clc_eid_table.ueid_cnt = 0;
1168 	smc_clc_eid_table.seid_enabled = 1;
1169 }
1170 
1171 void smc_clc_exit(void)
1172 {
1173 	smc_clc_ueid_remove(NULL);
1174 }
1175