xref: /openbmc/linux/net/smc/smc_clc.c (revision 83146efc)
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 IS_ENABLED(CONFIG_S390)
159 	if (!rc && !smc_clc_eid_table.ueid_cnt) {
160 		smc_clc_eid_table.seid_enabled = 1;
161 		rc = -EAGAIN;	/* indicate success and enabling of seid */
162 	}
163 #endif
164 	write_unlock(&smc_clc_eid_table.lock);
165 	return rc;
166 }
167 
168 int smc_nl_remove_ueid(struct sk_buff *skb, struct genl_info *info)
169 {
170 	struct nlattr *nla_ueid = info->attrs[SMC_NLA_EID_TABLE_ENTRY];
171 	char *ueid;
172 
173 	if (!nla_ueid || nla_len(nla_ueid) != SMC_MAX_EID_LEN + 1)
174 		return -EINVAL;
175 	ueid = (char *)nla_data(nla_ueid);
176 
177 	return smc_clc_ueid_remove(ueid);
178 }
179 
180 int smc_nl_flush_ueid(struct sk_buff *skb, struct genl_info *info)
181 {
182 	smc_clc_ueid_remove(NULL);
183 	return 0;
184 }
185 
186 static int smc_nl_ueid_dumpinfo(struct sk_buff *skb, u32 portid, u32 seq,
187 				u32 flags, char *ueid)
188 {
189 	char ueid_str[SMC_MAX_EID_LEN + 1];
190 	void *hdr;
191 
192 	hdr = genlmsg_put(skb, portid, seq, &smc_gen_nl_family,
193 			  flags, SMC_NETLINK_DUMP_UEID);
194 	if (!hdr)
195 		return -ENOMEM;
196 	memcpy(ueid_str, ueid, SMC_MAX_EID_LEN);
197 	ueid_str[SMC_MAX_EID_LEN] = 0;
198 	if (nla_put_string(skb, SMC_NLA_EID_TABLE_ENTRY, ueid_str)) {
199 		genlmsg_cancel(skb, hdr);
200 		return -EMSGSIZE;
201 	}
202 	genlmsg_end(skb, hdr);
203 	return 0;
204 }
205 
206 static int _smc_nl_ueid_dump(struct sk_buff *skb, u32 portid, u32 seq,
207 			     int start_idx)
208 {
209 	struct smc_clc_eid_entry *lst_ueid;
210 	int idx = 0;
211 
212 	read_lock(&smc_clc_eid_table.lock);
213 	list_for_each_entry(lst_ueid, &smc_clc_eid_table.list, list) {
214 		if (idx++ < start_idx)
215 			continue;
216 		if (smc_nl_ueid_dumpinfo(skb, portid, seq, NLM_F_MULTI,
217 					 lst_ueid->eid)) {
218 			--idx;
219 			break;
220 		}
221 	}
222 	read_unlock(&smc_clc_eid_table.lock);
223 	return idx;
224 }
225 
226 int smc_nl_dump_ueid(struct sk_buff *skb, struct netlink_callback *cb)
227 {
228 	struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
229 	int idx;
230 
231 	idx = _smc_nl_ueid_dump(skb, NETLINK_CB(cb->skb).portid,
232 				cb->nlh->nlmsg_seq, cb_ctx->pos[0]);
233 
234 	cb_ctx->pos[0] = idx;
235 	return skb->len;
236 }
237 
238 int smc_nl_dump_seid(struct sk_buff *skb, struct netlink_callback *cb)
239 {
240 	struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
241 	char seid_str[SMC_MAX_EID_LEN + 1];
242 	u8 seid_enabled;
243 	void *hdr;
244 	u8 *seid;
245 
246 	if (cb_ctx->pos[0])
247 		return skb->len;
248 
249 	hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
250 			  &smc_gen_nl_family, NLM_F_MULTI,
251 			  SMC_NETLINK_DUMP_SEID);
252 	if (!hdr)
253 		return -ENOMEM;
254 	if (!smc_ism_is_v2_capable())
255 		goto end;
256 
257 	smc_ism_get_system_eid(&seid);
258 	memcpy(seid_str, seid, SMC_MAX_EID_LEN);
259 	seid_str[SMC_MAX_EID_LEN] = 0;
260 	if (nla_put_string(skb, SMC_NLA_SEID_ENTRY, seid_str))
261 		goto err;
262 	read_lock(&smc_clc_eid_table.lock);
263 	seid_enabled = smc_clc_eid_table.seid_enabled;
264 	read_unlock(&smc_clc_eid_table.lock);
265 	if (nla_put_u8(skb, SMC_NLA_SEID_ENABLED, seid_enabled))
266 		goto err;
267 end:
268 	genlmsg_end(skb, hdr);
269 	cb_ctx->pos[0]++;
270 	return skb->len;
271 err:
272 	genlmsg_cancel(skb, hdr);
273 	return -EMSGSIZE;
274 }
275 
276 int smc_nl_enable_seid(struct sk_buff *skb, struct genl_info *info)
277 {
278 #if IS_ENABLED(CONFIG_S390)
279 	write_lock(&smc_clc_eid_table.lock);
280 	smc_clc_eid_table.seid_enabled = 1;
281 	write_unlock(&smc_clc_eid_table.lock);
282 	return 0;
283 #else
284 	return -EOPNOTSUPP;
285 #endif
286 }
287 
288 int smc_nl_disable_seid(struct sk_buff *skb, struct genl_info *info)
289 {
290 	int rc = 0;
291 
292 #if IS_ENABLED(CONFIG_S390)
293 	write_lock(&smc_clc_eid_table.lock);
294 	if (!smc_clc_eid_table.ueid_cnt)
295 		rc = -ENOENT;
296 	else
297 		smc_clc_eid_table.seid_enabled = 0;
298 	write_unlock(&smc_clc_eid_table.lock);
299 #else
300 	rc = -EOPNOTSUPP;
301 #endif
302 	return rc;
303 }
304 
305 static bool _smc_clc_match_ueid(u8 *peer_ueid)
306 {
307 	struct smc_clc_eid_entry *tmp_ueid;
308 
309 	list_for_each_entry(tmp_ueid, &smc_clc_eid_table.list, list) {
310 		if (!memcmp(tmp_ueid->eid, peer_ueid, SMC_MAX_EID_LEN))
311 			return true;
312 	}
313 	return false;
314 }
315 
316 bool smc_clc_match_eid(u8 *negotiated_eid,
317 		       struct smc_clc_v2_extension *smc_v2_ext,
318 		       u8 *peer_eid, u8 *local_eid)
319 {
320 	bool match = false;
321 	int i;
322 
323 	negotiated_eid[0] = 0;
324 	read_lock(&smc_clc_eid_table.lock);
325 	if (peer_eid && local_eid &&
326 	    smc_clc_eid_table.seid_enabled &&
327 	    smc_v2_ext->hdr.flag.seid &&
328 	    !memcmp(peer_eid, local_eid, SMC_MAX_EID_LEN)) {
329 		memcpy(negotiated_eid, peer_eid, SMC_MAX_EID_LEN);
330 		match = true;
331 		goto out;
332 	}
333 
334 	for (i = 0; i < smc_v2_ext->hdr.eid_cnt; i++) {
335 		if (_smc_clc_match_ueid(smc_v2_ext->user_eids[i])) {
336 			memcpy(negotiated_eid, smc_v2_ext->user_eids[i],
337 			       SMC_MAX_EID_LEN);
338 			match = true;
339 			goto out;
340 		}
341 	}
342 out:
343 	read_unlock(&smc_clc_eid_table.lock);
344 	return match;
345 }
346 
347 /* check arriving CLC proposal */
348 static bool smc_clc_msg_prop_valid(struct smc_clc_msg_proposal *pclc)
349 {
350 	struct smc_clc_msg_proposal_prefix *pclc_prfx;
351 	struct smc_clc_smcd_v2_extension *smcd_v2_ext;
352 	struct smc_clc_msg_hdr *hdr = &pclc->hdr;
353 	struct smc_clc_v2_extension *v2_ext;
354 
355 	v2_ext = smc_get_clc_v2_ext(pclc);
356 	pclc_prfx = smc_clc_proposal_get_prefix(pclc);
357 	if (hdr->version == SMC_V1) {
358 		if (hdr->typev1 == SMC_TYPE_N)
359 			return false;
360 		if (ntohs(hdr->length) !=
361 			sizeof(*pclc) + ntohs(pclc->iparea_offset) +
362 			sizeof(*pclc_prfx) +
363 			pclc_prfx->ipv6_prefixes_cnt *
364 				sizeof(struct smc_clc_ipv6_prefix) +
365 			sizeof(struct smc_clc_msg_trail))
366 			return false;
367 	} else {
368 		if (ntohs(hdr->length) !=
369 			sizeof(*pclc) +
370 			sizeof(struct smc_clc_msg_smcd) +
371 			(hdr->typev1 != SMC_TYPE_N ?
372 				sizeof(*pclc_prfx) +
373 				pclc_prfx->ipv6_prefixes_cnt *
374 				sizeof(struct smc_clc_ipv6_prefix) : 0) +
375 			(hdr->typev2 != SMC_TYPE_N ?
376 				sizeof(*v2_ext) +
377 				v2_ext->hdr.eid_cnt * SMC_MAX_EID_LEN : 0) +
378 			(smcd_indicated(hdr->typev2) ?
379 				sizeof(*smcd_v2_ext) + v2_ext->hdr.ism_gid_cnt *
380 					sizeof(struct smc_clc_smcd_gid_chid) :
381 				0) +
382 			sizeof(struct smc_clc_msg_trail))
383 			return false;
384 	}
385 	return true;
386 }
387 
388 /* check arriving CLC accept or confirm */
389 static bool
390 smc_clc_msg_acc_conf_valid(struct smc_clc_msg_accept_confirm_v2 *clc_v2)
391 {
392 	struct smc_clc_msg_hdr *hdr = &clc_v2->hdr;
393 
394 	if (hdr->typev1 != SMC_TYPE_R && hdr->typev1 != SMC_TYPE_D)
395 		return false;
396 	if (hdr->version == SMC_V1) {
397 		if ((hdr->typev1 == SMC_TYPE_R &&
398 		     ntohs(hdr->length) != SMCR_CLC_ACCEPT_CONFIRM_LEN) ||
399 		    (hdr->typev1 == SMC_TYPE_D &&
400 		     ntohs(hdr->length) != SMCD_CLC_ACCEPT_CONFIRM_LEN))
401 			return false;
402 	} else {
403 		if (hdr->typev1 == SMC_TYPE_D &&
404 		    ntohs(hdr->length) < SMCD_CLC_ACCEPT_CONFIRM_LEN_V2)
405 			return false;
406 		if (hdr->typev1 == SMC_TYPE_R &&
407 		    ntohs(hdr->length) < SMCR_CLC_ACCEPT_CONFIRM_LEN_V2)
408 			return false;
409 	}
410 	return true;
411 }
412 
413 /* check arriving CLC decline */
414 static bool
415 smc_clc_msg_decl_valid(struct smc_clc_msg_decline *dclc)
416 {
417 	struct smc_clc_msg_hdr *hdr = &dclc->hdr;
418 
419 	if (hdr->typev1 != SMC_TYPE_R && hdr->typev1 != SMC_TYPE_D)
420 		return false;
421 	if (hdr->version == SMC_V1) {
422 		if (ntohs(hdr->length) != sizeof(struct smc_clc_msg_decline))
423 			return false;
424 	} else {
425 		if (ntohs(hdr->length) != sizeof(struct smc_clc_msg_decline_v2))
426 			return false;
427 	}
428 	return true;
429 }
430 
431 static int smc_clc_fill_fce(struct smc_clc_first_contact_ext_v2x *fce,
432 			    struct smc_init_info *ini)
433 {
434 	int ret = sizeof(*fce);
435 
436 	memset(fce, 0, sizeof(*fce));
437 	fce->fce_v2_base.os_type = SMC_CLC_OS_LINUX;
438 	fce->fce_v2_base.release = ini->release_nr;
439 	memcpy(fce->fce_v2_base.hostname, smc_hostname, sizeof(smc_hostname));
440 	if (ini->is_smcd && ini->release_nr < SMC_RELEASE_1) {
441 		ret = sizeof(struct smc_clc_first_contact_ext);
442 		goto out;
443 	}
444 
445 	if (ini->release_nr >= SMC_RELEASE_1) {
446 		if (!ini->is_smcd) {
447 			fce->max_conns = ini->max_conns;
448 			fce->max_links = ini->max_links;
449 		}
450 	}
451 
452 out:
453 	return ret;
454 }
455 
456 /* check if received message has a correct header length and contains valid
457  * heading and trailing eyecatchers
458  */
459 static bool smc_clc_msg_hdr_valid(struct smc_clc_msg_hdr *clcm, bool check_trl)
460 {
461 	struct smc_clc_msg_accept_confirm_v2 *clc_v2;
462 	struct smc_clc_msg_proposal *pclc;
463 	struct smc_clc_msg_decline *dclc;
464 	struct smc_clc_msg_trail *trl;
465 
466 	if (memcmp(clcm->eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER)) &&
467 	    memcmp(clcm->eyecatcher, SMCD_EYECATCHER, sizeof(SMCD_EYECATCHER)))
468 		return false;
469 	switch (clcm->type) {
470 	case SMC_CLC_PROPOSAL:
471 		pclc = (struct smc_clc_msg_proposal *)clcm;
472 		if (!smc_clc_msg_prop_valid(pclc))
473 			return false;
474 		trl = (struct smc_clc_msg_trail *)
475 			((u8 *)pclc + ntohs(pclc->hdr.length) - sizeof(*trl));
476 		break;
477 	case SMC_CLC_ACCEPT:
478 	case SMC_CLC_CONFIRM:
479 		clc_v2 = (struct smc_clc_msg_accept_confirm_v2 *)clcm;
480 		if (!smc_clc_msg_acc_conf_valid(clc_v2))
481 			return false;
482 		trl = (struct smc_clc_msg_trail *)
483 			((u8 *)clc_v2 + ntohs(clc_v2->hdr.length) -
484 							sizeof(*trl));
485 		break;
486 	case SMC_CLC_DECLINE:
487 		dclc = (struct smc_clc_msg_decline *)clcm;
488 		if (!smc_clc_msg_decl_valid(dclc))
489 			return false;
490 		check_trl = false;
491 		break;
492 	default:
493 		return false;
494 	}
495 	if (check_trl &&
496 	    memcmp(trl->eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER)) &&
497 	    memcmp(trl->eyecatcher, SMCD_EYECATCHER, sizeof(SMCD_EYECATCHER)))
498 		return false;
499 	return true;
500 }
501 
502 /* find ipv4 addr on device and get the prefix len, fill CLC proposal msg */
503 static int smc_clc_prfx_set4_rcu(struct dst_entry *dst, __be32 ipv4,
504 				 struct smc_clc_msg_proposal_prefix *prop)
505 {
506 	struct in_device *in_dev = __in_dev_get_rcu(dst->dev);
507 	const struct in_ifaddr *ifa;
508 
509 	if (!in_dev)
510 		return -ENODEV;
511 
512 	in_dev_for_each_ifa_rcu(ifa, in_dev) {
513 		if (!inet_ifa_match(ipv4, ifa))
514 			continue;
515 		prop->prefix_len = inet_mask_len(ifa->ifa_mask);
516 		prop->outgoing_subnet = ifa->ifa_address & ifa->ifa_mask;
517 		/* prop->ipv6_prefixes_cnt = 0; already done by memset before */
518 		return 0;
519 	}
520 	return -ENOENT;
521 }
522 
523 /* fill CLC proposal msg with ipv6 prefixes from device */
524 static int smc_clc_prfx_set6_rcu(struct dst_entry *dst,
525 				 struct smc_clc_msg_proposal_prefix *prop,
526 				 struct smc_clc_ipv6_prefix *ipv6_prfx)
527 {
528 #if IS_ENABLED(CONFIG_IPV6)
529 	struct inet6_dev *in6_dev = __in6_dev_get(dst->dev);
530 	struct inet6_ifaddr *ifa;
531 	int cnt = 0;
532 
533 	if (!in6_dev)
534 		return -ENODEV;
535 	/* use a maximum of 8 IPv6 prefixes from device */
536 	list_for_each_entry(ifa, &in6_dev->addr_list, if_list) {
537 		if (ipv6_addr_type(&ifa->addr) & IPV6_ADDR_LINKLOCAL)
538 			continue;
539 		ipv6_addr_prefix(&ipv6_prfx[cnt].prefix,
540 				 &ifa->addr, ifa->prefix_len);
541 		ipv6_prfx[cnt].prefix_len = ifa->prefix_len;
542 		cnt++;
543 		if (cnt == SMC_CLC_MAX_V6_PREFIX)
544 			break;
545 	}
546 	prop->ipv6_prefixes_cnt = cnt;
547 	if (cnt)
548 		return 0;
549 #endif
550 	return -ENOENT;
551 }
552 
553 /* retrieve and set prefixes in CLC proposal msg */
554 static int smc_clc_prfx_set(struct socket *clcsock,
555 			    struct smc_clc_msg_proposal_prefix *prop,
556 			    struct smc_clc_ipv6_prefix *ipv6_prfx)
557 {
558 	struct dst_entry *dst = sk_dst_get(clcsock->sk);
559 	struct sockaddr_storage addrs;
560 	struct sockaddr_in6 *addr6;
561 	struct sockaddr_in *addr;
562 	int rc = -ENOENT;
563 
564 	if (!dst) {
565 		rc = -ENOTCONN;
566 		goto out;
567 	}
568 	if (!dst->dev) {
569 		rc = -ENODEV;
570 		goto out_rel;
571 	}
572 	/* get address to which the internal TCP socket is bound */
573 	if (kernel_getsockname(clcsock, (struct sockaddr *)&addrs) < 0)
574 		goto out_rel;
575 	/* analyze IP specific data of net_device belonging to TCP socket */
576 	addr6 = (struct sockaddr_in6 *)&addrs;
577 	rcu_read_lock();
578 	if (addrs.ss_family == PF_INET) {
579 		/* IPv4 */
580 		addr = (struct sockaddr_in *)&addrs;
581 		rc = smc_clc_prfx_set4_rcu(dst, addr->sin_addr.s_addr, prop);
582 	} else if (ipv6_addr_v4mapped(&addr6->sin6_addr)) {
583 		/* mapped IPv4 address - peer is IPv4 only */
584 		rc = smc_clc_prfx_set4_rcu(dst, addr6->sin6_addr.s6_addr32[3],
585 					   prop);
586 	} else {
587 		/* IPv6 */
588 		rc = smc_clc_prfx_set6_rcu(dst, prop, ipv6_prfx);
589 	}
590 	rcu_read_unlock();
591 out_rel:
592 	dst_release(dst);
593 out:
594 	return rc;
595 }
596 
597 /* match ipv4 addrs of dev against addr in CLC proposal */
598 static int smc_clc_prfx_match4_rcu(struct net_device *dev,
599 				   struct smc_clc_msg_proposal_prefix *prop)
600 {
601 	struct in_device *in_dev = __in_dev_get_rcu(dev);
602 	const struct in_ifaddr *ifa;
603 
604 	if (!in_dev)
605 		return -ENODEV;
606 	in_dev_for_each_ifa_rcu(ifa, in_dev) {
607 		if (prop->prefix_len == inet_mask_len(ifa->ifa_mask) &&
608 		    inet_ifa_match(prop->outgoing_subnet, ifa))
609 			return 0;
610 	}
611 
612 	return -ENOENT;
613 }
614 
615 /* match ipv6 addrs of dev against addrs in CLC proposal */
616 static int smc_clc_prfx_match6_rcu(struct net_device *dev,
617 				   struct smc_clc_msg_proposal_prefix *prop)
618 {
619 #if IS_ENABLED(CONFIG_IPV6)
620 	struct inet6_dev *in6_dev = __in6_dev_get(dev);
621 	struct smc_clc_ipv6_prefix *ipv6_prfx;
622 	struct inet6_ifaddr *ifa;
623 	int i, max;
624 
625 	if (!in6_dev)
626 		return -ENODEV;
627 	/* ipv6 prefix list starts behind smc_clc_msg_proposal_prefix */
628 	ipv6_prfx = (struct smc_clc_ipv6_prefix *)((u8 *)prop + sizeof(*prop));
629 	max = min_t(u8, prop->ipv6_prefixes_cnt, SMC_CLC_MAX_V6_PREFIX);
630 	list_for_each_entry(ifa, &in6_dev->addr_list, if_list) {
631 		if (ipv6_addr_type(&ifa->addr) & IPV6_ADDR_LINKLOCAL)
632 			continue;
633 		for (i = 0; i < max; i++) {
634 			if (ifa->prefix_len == ipv6_prfx[i].prefix_len &&
635 			    ipv6_prefix_equal(&ifa->addr, &ipv6_prfx[i].prefix,
636 					      ifa->prefix_len))
637 				return 0;
638 		}
639 	}
640 #endif
641 	return -ENOENT;
642 }
643 
644 /* check if proposed prefixes match one of our device prefixes */
645 int smc_clc_prfx_match(struct socket *clcsock,
646 		       struct smc_clc_msg_proposal_prefix *prop)
647 {
648 	struct dst_entry *dst = sk_dst_get(clcsock->sk);
649 	int rc;
650 
651 	if (!dst) {
652 		rc = -ENOTCONN;
653 		goto out;
654 	}
655 	if (!dst->dev) {
656 		rc = -ENODEV;
657 		goto out_rel;
658 	}
659 	rcu_read_lock();
660 	if (!prop->ipv6_prefixes_cnt)
661 		rc = smc_clc_prfx_match4_rcu(dst->dev, prop);
662 	else
663 		rc = smc_clc_prfx_match6_rcu(dst->dev, prop);
664 	rcu_read_unlock();
665 out_rel:
666 	dst_release(dst);
667 out:
668 	return rc;
669 }
670 
671 /* Wait for data on the tcp-socket, analyze received data
672  * Returns:
673  * 0 if success and it was not a decline that we received.
674  * SMC_CLC_DECL_REPLY if decline received for fallback w/o another decl send.
675  * clcsock error, -EINTR, -ECONNRESET, -EPROTO otherwise.
676  */
677 int smc_clc_wait_msg(struct smc_sock *smc, void *buf, int buflen,
678 		     u8 expected_type, unsigned long timeout)
679 {
680 	long rcvtimeo = smc->clcsock->sk->sk_rcvtimeo;
681 	struct sock *clc_sk = smc->clcsock->sk;
682 	struct smc_clc_msg_hdr *clcm = buf;
683 	struct msghdr msg = {NULL, 0};
684 	int reason_code = 0;
685 	struct kvec vec = {buf, buflen};
686 	int len, datlen, recvlen;
687 	bool check_trl = true;
688 	int krflags;
689 
690 	/* peek the first few bytes to determine length of data to receive
691 	 * so we don't consume any subsequent CLC message or payload data
692 	 * in the TCP byte stream
693 	 */
694 	/*
695 	 * Caller must make sure that buflen is no less than
696 	 * sizeof(struct smc_clc_msg_hdr)
697 	 */
698 	krflags = MSG_PEEK | MSG_WAITALL;
699 	clc_sk->sk_rcvtimeo = timeout;
700 	iov_iter_kvec(&msg.msg_iter, ITER_DEST, &vec, 1,
701 			sizeof(struct smc_clc_msg_hdr));
702 	len = sock_recvmsg(smc->clcsock, &msg, krflags);
703 	if (signal_pending(current)) {
704 		reason_code = -EINTR;
705 		clc_sk->sk_err = EINTR;
706 		smc->sk.sk_err = EINTR;
707 		goto out;
708 	}
709 	if (clc_sk->sk_err) {
710 		reason_code = -clc_sk->sk_err;
711 		if (clc_sk->sk_err == EAGAIN &&
712 		    expected_type == SMC_CLC_DECLINE)
713 			clc_sk->sk_err = 0; /* reset for fallback usage */
714 		else
715 			smc->sk.sk_err = clc_sk->sk_err;
716 		goto out;
717 	}
718 	if (!len) { /* peer has performed orderly shutdown */
719 		smc->sk.sk_err = ECONNRESET;
720 		reason_code = -ECONNRESET;
721 		goto out;
722 	}
723 	if (len < 0) {
724 		if (len != -EAGAIN || expected_type != SMC_CLC_DECLINE)
725 			smc->sk.sk_err = -len;
726 		reason_code = len;
727 		goto out;
728 	}
729 	datlen = ntohs(clcm->length);
730 	if ((len < sizeof(struct smc_clc_msg_hdr)) ||
731 	    (clcm->version < SMC_V1) ||
732 	    ((clcm->type != SMC_CLC_DECLINE) &&
733 	     (clcm->type != expected_type))) {
734 		smc->sk.sk_err = EPROTO;
735 		reason_code = -EPROTO;
736 		goto out;
737 	}
738 
739 	/* receive the complete CLC message */
740 	memset(&msg, 0, sizeof(struct msghdr));
741 	if (datlen > buflen) {
742 		check_trl = false;
743 		recvlen = buflen;
744 	} else {
745 		recvlen = datlen;
746 	}
747 	iov_iter_kvec(&msg.msg_iter, ITER_DEST, &vec, 1, recvlen);
748 	krflags = MSG_WAITALL;
749 	len = sock_recvmsg(smc->clcsock, &msg, krflags);
750 	if (len < recvlen || !smc_clc_msg_hdr_valid(clcm, check_trl)) {
751 		smc->sk.sk_err = EPROTO;
752 		reason_code = -EPROTO;
753 		goto out;
754 	}
755 	datlen -= len;
756 	while (datlen) {
757 		u8 tmp[SMC_CLC_RECV_BUF_LEN];
758 
759 		vec.iov_base = &tmp;
760 		vec.iov_len = SMC_CLC_RECV_BUF_LEN;
761 		/* receive remaining proposal message */
762 		recvlen = datlen > SMC_CLC_RECV_BUF_LEN ?
763 						SMC_CLC_RECV_BUF_LEN : datlen;
764 		iov_iter_kvec(&msg.msg_iter, ITER_DEST, &vec, 1, recvlen);
765 		len = sock_recvmsg(smc->clcsock, &msg, krflags);
766 		datlen -= len;
767 	}
768 	if (clcm->type == SMC_CLC_DECLINE) {
769 		struct smc_clc_msg_decline *dclc;
770 
771 		dclc = (struct smc_clc_msg_decline *)clcm;
772 		reason_code = SMC_CLC_DECL_PEERDECL;
773 		smc->peer_diagnosis = ntohl(dclc->peer_diagnosis);
774 		if (((struct smc_clc_msg_decline *)buf)->hdr.typev2 &
775 						SMC_FIRST_CONTACT_MASK) {
776 			smc->conn.lgr->sync_err = 1;
777 			smc_lgr_terminate_sched(smc->conn.lgr);
778 		}
779 	}
780 
781 out:
782 	clc_sk->sk_rcvtimeo = rcvtimeo;
783 	return reason_code;
784 }
785 
786 /* send CLC DECLINE message across internal TCP socket */
787 int smc_clc_send_decline(struct smc_sock *smc, u32 peer_diag_info, u8 version)
788 {
789 	struct smc_clc_msg_decline *dclc_v1;
790 	struct smc_clc_msg_decline_v2 dclc;
791 	struct msghdr msg;
792 	int len, send_len;
793 	struct kvec vec;
794 
795 	dclc_v1 = (struct smc_clc_msg_decline *)&dclc;
796 	memset(&dclc, 0, sizeof(dclc));
797 	memcpy(dclc.hdr.eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
798 	dclc.hdr.type = SMC_CLC_DECLINE;
799 	dclc.hdr.version = version;
800 	dclc.os_type = version == SMC_V1 ? 0 : SMC_CLC_OS_LINUX;
801 	dclc.hdr.typev2 = (peer_diag_info == SMC_CLC_DECL_SYNCERR) ?
802 						SMC_FIRST_CONTACT_MASK : 0;
803 	if ((!smc_conn_lgr_valid(&smc->conn) || !smc->conn.lgr->is_smcd) &&
804 	    smc_ib_is_valid_local_systemid())
805 		memcpy(dclc.id_for_peer, local_systemid,
806 		       sizeof(local_systemid));
807 	dclc.peer_diagnosis = htonl(peer_diag_info);
808 	if (version == SMC_V1) {
809 		memcpy(dclc_v1->trl.eyecatcher, SMC_EYECATCHER,
810 		       sizeof(SMC_EYECATCHER));
811 		send_len = sizeof(*dclc_v1);
812 	} else {
813 		memcpy(dclc.trl.eyecatcher, SMC_EYECATCHER,
814 		       sizeof(SMC_EYECATCHER));
815 		send_len = sizeof(dclc);
816 	}
817 	dclc.hdr.length = htons(send_len);
818 
819 	memset(&msg, 0, sizeof(msg));
820 	vec.iov_base = &dclc;
821 	vec.iov_len = send_len;
822 	len = kernel_sendmsg(smc->clcsock, &msg, &vec, 1, send_len);
823 	if (len < 0 || len < send_len)
824 		len = -EPROTO;
825 	return len > 0 ? 0 : len;
826 }
827 
828 /* send CLC PROPOSAL message across internal TCP socket */
829 int smc_clc_send_proposal(struct smc_sock *smc, struct smc_init_info *ini)
830 {
831 	struct smc_clc_smcd_v2_extension *smcd_v2_ext;
832 	struct smc_clc_msg_proposal_prefix *pclc_prfx;
833 	struct smc_clc_msg_proposal *pclc_base;
834 	struct smc_clc_smcd_gid_chid *gidchids;
835 	struct smc_clc_msg_proposal_area *pclc;
836 	struct smc_clc_ipv6_prefix *ipv6_prfx;
837 	struct smc_clc_v2_extension *v2_ext;
838 	struct smc_clc_msg_smcd *pclc_smcd;
839 	struct smc_clc_msg_trail *trl;
840 	struct smcd_dev *smcd;
841 	int len, i, plen, rc;
842 	int reason_code = 0;
843 	struct kvec vec[8];
844 	struct msghdr msg;
845 
846 	pclc = kzalloc(sizeof(*pclc), GFP_KERNEL);
847 	if (!pclc)
848 		return -ENOMEM;
849 
850 	pclc_base = &pclc->pclc_base;
851 	pclc_smcd = &pclc->pclc_smcd;
852 	pclc_prfx = &pclc->pclc_prfx;
853 	ipv6_prfx = pclc->pclc_prfx_ipv6;
854 	v2_ext = &pclc->pclc_v2_ext;
855 	smcd_v2_ext = &pclc->pclc_smcd_v2_ext;
856 	gidchids = pclc->pclc_gidchids;
857 	trl = &pclc->pclc_trl;
858 
859 	pclc_base->hdr.version = SMC_V2;
860 	pclc_base->hdr.typev1 = ini->smc_type_v1;
861 	pclc_base->hdr.typev2 = ini->smc_type_v2;
862 	plen = sizeof(*pclc_base) + sizeof(*pclc_smcd) + sizeof(*trl);
863 
864 	/* retrieve ip prefixes for CLC proposal msg */
865 	if (ini->smc_type_v1 != SMC_TYPE_N) {
866 		rc = smc_clc_prfx_set(smc->clcsock, pclc_prfx, ipv6_prfx);
867 		if (rc) {
868 			if (ini->smc_type_v2 == SMC_TYPE_N) {
869 				kfree(pclc);
870 				return SMC_CLC_DECL_CNFERR;
871 			}
872 			pclc_base->hdr.typev1 = SMC_TYPE_N;
873 		} else {
874 			pclc_base->iparea_offset = htons(sizeof(*pclc_smcd));
875 			plen += sizeof(*pclc_prfx) +
876 					pclc_prfx->ipv6_prefixes_cnt *
877 					sizeof(ipv6_prfx[0]);
878 		}
879 	}
880 
881 	/* build SMC Proposal CLC message */
882 	memcpy(pclc_base->hdr.eyecatcher, SMC_EYECATCHER,
883 	       sizeof(SMC_EYECATCHER));
884 	pclc_base->hdr.type = SMC_CLC_PROPOSAL;
885 	if (smcr_indicated(ini->smc_type_v1)) {
886 		/* add SMC-R specifics */
887 		memcpy(pclc_base->lcl.id_for_peer, local_systemid,
888 		       sizeof(local_systemid));
889 		memcpy(pclc_base->lcl.gid, ini->ib_gid, SMC_GID_SIZE);
890 		memcpy(pclc_base->lcl.mac, &ini->ib_dev->mac[ini->ib_port - 1],
891 		       ETH_ALEN);
892 	}
893 	if (smcd_indicated(ini->smc_type_v1)) {
894 		/* add SMC-D specifics */
895 		if (ini->ism_dev[0]) {
896 			smcd = ini->ism_dev[0];
897 			pclc_smcd->ism.gid =
898 				htonll(smcd->ops->get_local_gid(smcd));
899 			pclc_smcd->ism.chid =
900 				htons(smc_ism_get_chid(ini->ism_dev[0]));
901 		}
902 	}
903 	if (ini->smc_type_v2 == SMC_TYPE_N) {
904 		pclc_smcd->v2_ext_offset = 0;
905 	} else {
906 		struct smc_clc_eid_entry *ueident;
907 		u16 v2_ext_offset;
908 
909 		v2_ext->hdr.flag.release = SMC_RELEASE;
910 		v2_ext_offset = sizeof(*pclc_smcd) -
911 			offsetofend(struct smc_clc_msg_smcd, v2_ext_offset);
912 		if (ini->smc_type_v1 != SMC_TYPE_N)
913 			v2_ext_offset += sizeof(*pclc_prfx) +
914 						pclc_prfx->ipv6_prefixes_cnt *
915 						sizeof(ipv6_prfx[0]);
916 		pclc_smcd->v2_ext_offset = htons(v2_ext_offset);
917 		plen += sizeof(*v2_ext);
918 
919 		read_lock(&smc_clc_eid_table.lock);
920 		v2_ext->hdr.eid_cnt = smc_clc_eid_table.ueid_cnt;
921 		plen += smc_clc_eid_table.ueid_cnt * SMC_MAX_EID_LEN;
922 		i = 0;
923 		list_for_each_entry(ueident, &smc_clc_eid_table.list, list) {
924 			memcpy(v2_ext->user_eids[i++], ueident->eid,
925 			       sizeof(ueident->eid));
926 		}
927 		read_unlock(&smc_clc_eid_table.lock);
928 	}
929 	if (smcd_indicated(ini->smc_type_v2)) {
930 		u8 *eid = NULL;
931 
932 		v2_ext->hdr.flag.seid = smc_clc_eid_table.seid_enabled;
933 		v2_ext->hdr.ism_gid_cnt = ini->ism_offered_cnt;
934 		v2_ext->hdr.smcd_v2_ext_offset = htons(sizeof(*v2_ext) -
935 				offsetofend(struct smc_clnt_opts_area_hdr,
936 					    smcd_v2_ext_offset) +
937 				v2_ext->hdr.eid_cnt * SMC_MAX_EID_LEN);
938 		smc_ism_get_system_eid(&eid);
939 		if (eid && v2_ext->hdr.flag.seid)
940 			memcpy(smcd_v2_ext->system_eid, eid, SMC_MAX_EID_LEN);
941 		plen += sizeof(*smcd_v2_ext);
942 		if (ini->ism_offered_cnt) {
943 			for (i = 1; i <= ini->ism_offered_cnt; i++) {
944 				smcd = ini->ism_dev[i];
945 				gidchids[i - 1].gid =
946 					htonll(smcd->ops->get_local_gid(smcd));
947 				gidchids[i - 1].chid =
948 					htons(smc_ism_get_chid(ini->ism_dev[i]));
949 			}
950 			plen += ini->ism_offered_cnt *
951 				sizeof(struct smc_clc_smcd_gid_chid);
952 		}
953 	}
954 	if (smcr_indicated(ini->smc_type_v2)) {
955 		memcpy(v2_ext->roce, ini->smcrv2.ib_gid_v2, SMC_GID_SIZE);
956 		v2_ext->max_conns = SMC_CONN_PER_LGR_PREFER;
957 		v2_ext->max_links = SMC_LINKS_PER_LGR_MAX_PREFER;
958 	}
959 
960 	pclc_base->hdr.length = htons(plen);
961 	memcpy(trl->eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
962 
963 	/* send SMC Proposal CLC message */
964 	memset(&msg, 0, sizeof(msg));
965 	i = 0;
966 	vec[i].iov_base = pclc_base;
967 	vec[i++].iov_len = sizeof(*pclc_base);
968 	vec[i].iov_base = pclc_smcd;
969 	vec[i++].iov_len = sizeof(*pclc_smcd);
970 	if (ini->smc_type_v1 != SMC_TYPE_N) {
971 		vec[i].iov_base = pclc_prfx;
972 		vec[i++].iov_len = sizeof(*pclc_prfx);
973 		if (pclc_prfx->ipv6_prefixes_cnt > 0) {
974 			vec[i].iov_base = ipv6_prfx;
975 			vec[i++].iov_len = pclc_prfx->ipv6_prefixes_cnt *
976 					   sizeof(ipv6_prfx[0]);
977 		}
978 	}
979 	if (ini->smc_type_v2 != SMC_TYPE_N) {
980 		vec[i].iov_base = v2_ext;
981 		vec[i++].iov_len = sizeof(*v2_ext) +
982 				   (v2_ext->hdr.eid_cnt * SMC_MAX_EID_LEN);
983 		if (smcd_indicated(ini->smc_type_v2)) {
984 			vec[i].iov_base = smcd_v2_ext;
985 			vec[i++].iov_len = sizeof(*smcd_v2_ext);
986 			if (ini->ism_offered_cnt) {
987 				vec[i].iov_base = gidchids;
988 				vec[i++].iov_len = ini->ism_offered_cnt *
989 					sizeof(struct smc_clc_smcd_gid_chid);
990 			}
991 		}
992 	}
993 	vec[i].iov_base = trl;
994 	vec[i++].iov_len = sizeof(*trl);
995 	/* due to the few bytes needed for clc-handshake this cannot block */
996 	len = kernel_sendmsg(smc->clcsock, &msg, vec, i, plen);
997 	if (len < 0) {
998 		smc->sk.sk_err = smc->clcsock->sk->sk_err;
999 		reason_code = -smc->sk.sk_err;
1000 	} else if (len < ntohs(pclc_base->hdr.length)) {
1001 		reason_code = -ENETUNREACH;
1002 		smc->sk.sk_err = -reason_code;
1003 	}
1004 
1005 	kfree(pclc);
1006 	return reason_code;
1007 }
1008 
1009 /* build and send CLC CONFIRM / ACCEPT message */
1010 static int smc_clc_send_confirm_accept(struct smc_sock *smc,
1011 				       struct smc_clc_msg_accept_confirm_v2 *clc_v2,
1012 				       int first_contact, u8 version,
1013 				       u8 *eid, struct smc_init_info *ini)
1014 {
1015 	struct smc_connection *conn = &smc->conn;
1016 	struct smc_clc_first_contact_ext_v2x fce;
1017 	struct smcd_dev *smcd = conn->lgr->smcd;
1018 	struct smc_clc_msg_accept_confirm *clc;
1019 	struct smc_clc_fce_gid_ext gle;
1020 	struct smc_clc_msg_trail trl;
1021 	int i, len, fce_len;
1022 	struct kvec vec[5];
1023 	struct msghdr msg;
1024 
1025 	/* send SMC Confirm CLC msg */
1026 	clc = (struct smc_clc_msg_accept_confirm *)clc_v2;
1027 	clc->hdr.version = version;	/* SMC version */
1028 	if (first_contact)
1029 		clc->hdr.typev2 |= SMC_FIRST_CONTACT_MASK;
1030 	if (conn->lgr->is_smcd) {
1031 		/* SMC-D specific settings */
1032 		memcpy(clc->hdr.eyecatcher, SMCD_EYECATCHER,
1033 		       sizeof(SMCD_EYECATCHER));
1034 		clc->hdr.typev1 = SMC_TYPE_D;
1035 		clc->d0.gid = htonll(smcd->ops->get_local_gid(smcd));
1036 		clc->d0.token = htonll(conn->rmb_desc->token);
1037 		clc->d0.dmbe_size = conn->rmbe_size_comp;
1038 		clc->d0.dmbe_idx = 0;
1039 		memcpy(&clc->d0.linkid, conn->lgr->id, SMC_LGR_ID_SIZE);
1040 		if (version == SMC_V1) {
1041 			clc->hdr.length = htons(SMCD_CLC_ACCEPT_CONFIRM_LEN);
1042 		} else {
1043 			clc_v2->d1.chid = htons(smc_ism_get_chid(smcd));
1044 			if (eid && eid[0])
1045 				memcpy(clc_v2->d1.eid, eid, SMC_MAX_EID_LEN);
1046 			len = SMCD_CLC_ACCEPT_CONFIRM_LEN_V2;
1047 			if (first_contact) {
1048 				fce_len = smc_clc_fill_fce(&fce, ini);
1049 				len += fce_len;
1050 			}
1051 			clc_v2->hdr.length = htons(len);
1052 		}
1053 		memcpy(trl.eyecatcher, SMCD_EYECATCHER,
1054 		       sizeof(SMCD_EYECATCHER));
1055 	} else {
1056 		struct smc_link *link = conn->lnk;
1057 
1058 		/* SMC-R specific settings */
1059 		memcpy(clc->hdr.eyecatcher, SMC_EYECATCHER,
1060 		       sizeof(SMC_EYECATCHER));
1061 		clc->hdr.typev1 = SMC_TYPE_R;
1062 		clc->hdr.length = htons(SMCR_CLC_ACCEPT_CONFIRM_LEN);
1063 		memcpy(clc->r0.lcl.id_for_peer, local_systemid,
1064 		       sizeof(local_systemid));
1065 		memcpy(&clc->r0.lcl.gid, link->gid, SMC_GID_SIZE);
1066 		memcpy(&clc->r0.lcl.mac, &link->smcibdev->mac[link->ibport - 1],
1067 		       ETH_ALEN);
1068 		hton24(clc->r0.qpn, link->roce_qp->qp_num);
1069 		clc->r0.rmb_rkey =
1070 			htonl(conn->rmb_desc->mr[link->link_idx]->rkey);
1071 		clc->r0.rmbe_idx = 1; /* for now: 1 RMB = 1 RMBE */
1072 		clc->r0.rmbe_alert_token = htonl(conn->alert_token_local);
1073 		switch (clc->hdr.type) {
1074 		case SMC_CLC_ACCEPT:
1075 			clc->r0.qp_mtu = link->path_mtu;
1076 			break;
1077 		case SMC_CLC_CONFIRM:
1078 			clc->r0.qp_mtu = min(link->path_mtu, link->peer_mtu);
1079 			break;
1080 		}
1081 		clc->r0.rmbe_size = conn->rmbe_size_comp;
1082 		clc->r0.rmb_dma_addr = conn->rmb_desc->is_vm ?
1083 			cpu_to_be64((uintptr_t)conn->rmb_desc->cpu_addr) :
1084 			cpu_to_be64((u64)sg_dma_address
1085 				    (conn->rmb_desc->sgt[link->link_idx].sgl));
1086 		hton24(clc->r0.psn, link->psn_initial);
1087 		if (version == SMC_V1) {
1088 			clc->hdr.length = htons(SMCR_CLC_ACCEPT_CONFIRM_LEN);
1089 		} else {
1090 			if (eid && eid[0])
1091 				memcpy(clc_v2->r1.eid, eid, SMC_MAX_EID_LEN);
1092 			len = SMCR_CLC_ACCEPT_CONFIRM_LEN_V2;
1093 			if (first_contact) {
1094 				fce_len = smc_clc_fill_fce(&fce, ini);
1095 				len += fce_len;
1096 				fce.fce_v2_base.v2_direct = !link->lgr->uses_gateway;
1097 				if (clc->hdr.type == SMC_CLC_CONFIRM) {
1098 					memset(&gle, 0, sizeof(gle));
1099 					gle.gid_cnt = ini->smcrv2.gidlist.len;
1100 					len += sizeof(gle);
1101 					len += gle.gid_cnt * sizeof(gle.gid[0]);
1102 				}
1103 			}
1104 			clc_v2->hdr.length = htons(len);
1105 		}
1106 		memcpy(trl.eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
1107 	}
1108 
1109 	memset(&msg, 0, sizeof(msg));
1110 	i = 0;
1111 	vec[i].iov_base = clc_v2;
1112 	if (version > SMC_V1)
1113 		vec[i++].iov_len = (clc->hdr.typev1 == SMC_TYPE_D ?
1114 					SMCD_CLC_ACCEPT_CONFIRM_LEN_V2 :
1115 					SMCR_CLC_ACCEPT_CONFIRM_LEN_V2) -
1116 				   sizeof(trl);
1117 	else
1118 		vec[i++].iov_len = (clc->hdr.typev1 == SMC_TYPE_D ?
1119 						SMCD_CLC_ACCEPT_CONFIRM_LEN :
1120 						SMCR_CLC_ACCEPT_CONFIRM_LEN) -
1121 				   sizeof(trl);
1122 	if (version > SMC_V1 && first_contact) {
1123 		vec[i].iov_base = &fce;
1124 		vec[i++].iov_len = fce_len;
1125 		if (!conn->lgr->is_smcd) {
1126 			if (clc->hdr.type == SMC_CLC_CONFIRM) {
1127 				vec[i].iov_base = &gle;
1128 				vec[i++].iov_len = sizeof(gle);
1129 				vec[i].iov_base = &ini->smcrv2.gidlist.list;
1130 				vec[i++].iov_len = gle.gid_cnt *
1131 						   sizeof(gle.gid[0]);
1132 			}
1133 		}
1134 	}
1135 	vec[i].iov_base = &trl;
1136 	vec[i++].iov_len = sizeof(trl);
1137 	return kernel_sendmsg(smc->clcsock, &msg, vec, 1,
1138 			      ntohs(clc->hdr.length));
1139 }
1140 
1141 /* send CLC CONFIRM message across internal TCP socket */
1142 int smc_clc_send_confirm(struct smc_sock *smc, bool clnt_first_contact,
1143 			 u8 version, u8 *eid, struct smc_init_info *ini)
1144 {
1145 	struct smc_clc_msg_accept_confirm_v2 cclc_v2;
1146 	int reason_code = 0;
1147 	int len;
1148 
1149 	/* send SMC Confirm CLC msg */
1150 	memset(&cclc_v2, 0, sizeof(cclc_v2));
1151 	cclc_v2.hdr.type = SMC_CLC_CONFIRM;
1152 	len = smc_clc_send_confirm_accept(smc, &cclc_v2, clnt_first_contact,
1153 					  version, eid, ini);
1154 	if (len < ntohs(cclc_v2.hdr.length)) {
1155 		if (len >= 0) {
1156 			reason_code = -ENETUNREACH;
1157 			smc->sk.sk_err = -reason_code;
1158 		} else {
1159 			smc->sk.sk_err = smc->clcsock->sk->sk_err;
1160 			reason_code = -smc->sk.sk_err;
1161 		}
1162 	}
1163 	return reason_code;
1164 }
1165 
1166 /* send CLC ACCEPT message across internal TCP socket */
1167 int smc_clc_send_accept(struct smc_sock *new_smc, bool srv_first_contact,
1168 			u8 version, u8 *negotiated_eid, struct smc_init_info *ini)
1169 {
1170 	struct smc_clc_msg_accept_confirm_v2 aclc_v2;
1171 	int len;
1172 
1173 	memset(&aclc_v2, 0, sizeof(aclc_v2));
1174 	aclc_v2.hdr.type = SMC_CLC_ACCEPT;
1175 	len = smc_clc_send_confirm_accept(new_smc, &aclc_v2, srv_first_contact,
1176 					  version, negotiated_eid, ini);
1177 	if (len < ntohs(aclc_v2.hdr.length))
1178 		len = len >= 0 ? -EPROTO : -new_smc->clcsock->sk->sk_err;
1179 
1180 	return len > 0 ? 0 : len;
1181 }
1182 
1183 int smc_clc_srv_v2x_features_validate(struct smc_clc_msg_proposal *pclc,
1184 				      struct smc_init_info *ini)
1185 {
1186 	struct smc_clc_v2_extension *pclc_v2_ext;
1187 
1188 	ini->max_conns = SMC_CONN_PER_LGR_MAX;
1189 	ini->max_links = SMC_LINKS_ADD_LNK_MAX;
1190 
1191 	if ((!(ini->smcd_version & SMC_V2) && !(ini->smcr_version & SMC_V2)) ||
1192 	    ini->release_nr < SMC_RELEASE_1)
1193 		return 0;
1194 
1195 	pclc_v2_ext = smc_get_clc_v2_ext(pclc);
1196 	if (!pclc_v2_ext)
1197 		return SMC_CLC_DECL_NOV2EXT;
1198 
1199 	if (ini->smcr_version & SMC_V2) {
1200 		ini->max_conns = min_t(u8, pclc_v2_ext->max_conns, SMC_CONN_PER_LGR_PREFER);
1201 		if (ini->max_conns < SMC_CONN_PER_LGR_MIN)
1202 			return SMC_CLC_DECL_MAXCONNERR;
1203 
1204 		ini->max_links = min_t(u8, pclc_v2_ext->max_links, SMC_LINKS_PER_LGR_MAX_PREFER);
1205 		if (ini->max_links < SMC_LINKS_ADD_LNK_MIN)
1206 			return SMC_CLC_DECL_MAXLINKERR;
1207 	}
1208 
1209 	return 0;
1210 }
1211 
1212 int smc_clc_clnt_v2x_features_validate(struct smc_clc_first_contact_ext *fce,
1213 				       struct smc_init_info *ini)
1214 {
1215 	struct smc_clc_first_contact_ext_v2x *fce_v2x =
1216 		(struct smc_clc_first_contact_ext_v2x *)fce;
1217 
1218 	if (ini->release_nr < SMC_RELEASE_1)
1219 		return 0;
1220 
1221 	if (!ini->is_smcd) {
1222 		if (fce_v2x->max_conns < SMC_CONN_PER_LGR_MIN)
1223 			return SMC_CLC_DECL_MAXCONNERR;
1224 		ini->max_conns = fce_v2x->max_conns;
1225 
1226 		if (fce_v2x->max_links > SMC_LINKS_ADD_LNK_MAX ||
1227 		    fce_v2x->max_links < SMC_LINKS_ADD_LNK_MIN)
1228 			return SMC_CLC_DECL_MAXLINKERR;
1229 		ini->max_links = fce_v2x->max_links;
1230 	}
1231 
1232 	return 0;
1233 }
1234 
1235 int smc_clc_v2x_features_confirm_check(struct smc_clc_msg_accept_confirm *cclc,
1236 				       struct smc_init_info *ini)
1237 {
1238 	struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
1239 		(struct smc_clc_msg_accept_confirm_v2 *)cclc;
1240 	struct smc_clc_first_contact_ext *fce =
1241 		smc_get_clc_first_contact_ext(clc_v2, ini->is_smcd);
1242 	struct smc_clc_first_contact_ext_v2x *fce_v2x =
1243 		(struct smc_clc_first_contact_ext_v2x *)fce;
1244 
1245 	if (cclc->hdr.version == SMC_V1 ||
1246 	    !(cclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK))
1247 		return 0;
1248 
1249 	if (ini->release_nr != fce->release)
1250 		return SMC_CLC_DECL_RELEASEERR;
1251 
1252 	if (fce->release < SMC_RELEASE_1)
1253 		return 0;
1254 
1255 	if (!ini->is_smcd) {
1256 		if (fce_v2x->max_conns != ini->max_conns)
1257 			return SMC_CLC_DECL_MAXCONNERR;
1258 		if (fce_v2x->max_links != ini->max_links)
1259 			return SMC_CLC_DECL_MAXLINKERR;
1260 	}
1261 
1262 	return 0;
1263 }
1264 
1265 void smc_clc_get_hostname(u8 **host)
1266 {
1267 	*host = &smc_hostname[0];
1268 }
1269 
1270 void __init smc_clc_init(void)
1271 {
1272 	struct new_utsname *u;
1273 
1274 	memset(smc_hostname, _S, sizeof(smc_hostname)); /* ASCII blanks */
1275 	u = utsname();
1276 	memcpy(smc_hostname, u->nodename,
1277 	       min_t(size_t, strlen(u->nodename), sizeof(smc_hostname)));
1278 
1279 	INIT_LIST_HEAD(&smc_clc_eid_table.list);
1280 	rwlock_init(&smc_clc_eid_table.lock);
1281 	smc_clc_eid_table.ueid_cnt = 0;
1282 #if IS_ENABLED(CONFIG_S390)
1283 	smc_clc_eid_table.seid_enabled = 1;
1284 #else
1285 	smc_clc_eid_table.seid_enabled = 0;
1286 #endif
1287 }
1288 
1289 void smc_clc_exit(void)
1290 {
1291 	smc_clc_ueid_remove(NULL);
1292 }
1293