xref: /openbmc/linux/net/smc/smc_clc.c (revision e7217d52)
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 *clc)
391 {
392 	struct smc_clc_msg_hdr *hdr = &clc->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_v2x(struct smc_clc_first_contact_ext_v2x *fce_v2x,
432 				struct smc_init_info *ini)
433 {
434 	int ret = sizeof(*fce_v2x);
435 
436 	memset(fce_v2x, 0, sizeof(*fce_v2x));
437 	fce_v2x->fce_v2_base.os_type = SMC_CLC_OS_LINUX;
438 	fce_v2x->fce_v2_base.release = ini->release_nr;
439 	memcpy(fce_v2x->fce_v2_base.hostname,
440 	       smc_hostname, sizeof(smc_hostname));
441 	if (ini->is_smcd && ini->release_nr < SMC_RELEASE_1) {
442 		ret = sizeof(struct smc_clc_first_contact_ext);
443 		goto out;
444 	}
445 
446 	if (ini->release_nr >= SMC_RELEASE_1) {
447 		if (!ini->is_smcd) {
448 			fce_v2x->max_conns = ini->max_conns;
449 			fce_v2x->max_links = ini->max_links;
450 		}
451 	}
452 
453 out:
454 	return ret;
455 }
456 
457 /* check if received message has a correct header length and contains valid
458  * heading and trailing eyecatchers
459  */
460 static bool smc_clc_msg_hdr_valid(struct smc_clc_msg_hdr *clcm, bool check_trl)
461 {
462 	struct smc_clc_msg_accept_confirm *clc;
463 	struct smc_clc_msg_proposal *pclc;
464 	struct smc_clc_msg_decline *dclc;
465 	struct smc_clc_msg_trail *trl;
466 
467 	if (memcmp(clcm->eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER)) &&
468 	    memcmp(clcm->eyecatcher, SMCD_EYECATCHER, sizeof(SMCD_EYECATCHER)))
469 		return false;
470 	switch (clcm->type) {
471 	case SMC_CLC_PROPOSAL:
472 		pclc = (struct smc_clc_msg_proposal *)clcm;
473 		if (!smc_clc_msg_prop_valid(pclc))
474 			return false;
475 		trl = (struct smc_clc_msg_trail *)
476 			((u8 *)pclc + ntohs(pclc->hdr.length) - sizeof(*trl));
477 		break;
478 	case SMC_CLC_ACCEPT:
479 	case SMC_CLC_CONFIRM:
480 		clc = (struct smc_clc_msg_accept_confirm *)clcm;
481 		if (!smc_clc_msg_acc_conf_valid(clc))
482 			return false;
483 		trl = (struct smc_clc_msg_trail *)
484 			((u8 *)clc + ntohs(clc->hdr.length) - 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 		struct smcd_gid smcd_gid;
895 
896 		/* add SMC-D specifics */
897 		if (ini->ism_dev[0]) {
898 			smcd = ini->ism_dev[0];
899 			smcd->ops->get_local_gid(smcd, &smcd_gid);
900 			pclc_smcd->ism.gid = htonll(smcd_gid.gid);
901 			pclc_smcd->ism.chid =
902 				htons(smc_ism_get_chid(ini->ism_dev[0]));
903 		}
904 	}
905 	if (ini->smc_type_v2 == SMC_TYPE_N) {
906 		pclc_smcd->v2_ext_offset = 0;
907 	} else {
908 		struct smc_clc_eid_entry *ueident;
909 		u16 v2_ext_offset;
910 
911 		v2_ext->hdr.flag.release = SMC_RELEASE;
912 		v2_ext_offset = sizeof(*pclc_smcd) -
913 			offsetofend(struct smc_clc_msg_smcd, v2_ext_offset);
914 		if (ini->smc_type_v1 != SMC_TYPE_N)
915 			v2_ext_offset += sizeof(*pclc_prfx) +
916 						pclc_prfx->ipv6_prefixes_cnt *
917 						sizeof(ipv6_prfx[0]);
918 		pclc_smcd->v2_ext_offset = htons(v2_ext_offset);
919 		plen += sizeof(*v2_ext);
920 
921 		read_lock(&smc_clc_eid_table.lock);
922 		v2_ext->hdr.eid_cnt = smc_clc_eid_table.ueid_cnt;
923 		plen += smc_clc_eid_table.ueid_cnt * SMC_MAX_EID_LEN;
924 		i = 0;
925 		list_for_each_entry(ueident, &smc_clc_eid_table.list, list) {
926 			memcpy(v2_ext->user_eids[i++], ueident->eid,
927 			       sizeof(ueident->eid));
928 		}
929 		read_unlock(&smc_clc_eid_table.lock);
930 	}
931 	if (smcd_indicated(ini->smc_type_v2)) {
932 		struct smcd_gid smcd_gid;
933 		u8 *eid = NULL;
934 		int entry = 0;
935 
936 		v2_ext->hdr.flag.seid = smc_clc_eid_table.seid_enabled;
937 		v2_ext->hdr.smcd_v2_ext_offset = htons(sizeof(*v2_ext) -
938 				offsetofend(struct smc_clnt_opts_area_hdr,
939 					    smcd_v2_ext_offset) +
940 				v2_ext->hdr.eid_cnt * SMC_MAX_EID_LEN);
941 		smc_ism_get_system_eid(&eid);
942 		if (eid && v2_ext->hdr.flag.seid)
943 			memcpy(smcd_v2_ext->system_eid, eid, SMC_MAX_EID_LEN);
944 		plen += sizeof(*smcd_v2_ext);
945 		if (ini->ism_offered_cnt) {
946 			for (i = 1; i <= ini->ism_offered_cnt; i++) {
947 				smcd = ini->ism_dev[i];
948 				smcd->ops->get_local_gid(smcd, &smcd_gid);
949 				gidchids[entry].chid =
950 					htons(smc_ism_get_chid(ini->ism_dev[i]));
951 				gidchids[entry].gid = htonll(smcd_gid.gid);
952 				if (smc_ism_is_virtual(smcd)) {
953 					/* a virtual ISM device takes two
954 					 * entries. CHID of the second entry
955 					 * repeats that of the first entry.
956 					 */
957 					gidchids[entry + 1].chid =
958 						gidchids[entry].chid;
959 					gidchids[entry + 1].gid =
960 						htonll(smcd_gid.gid_ext);
961 					entry++;
962 				}
963 				entry++;
964 			}
965 			plen += entry * sizeof(struct smc_clc_smcd_gid_chid);
966 		}
967 		v2_ext->hdr.ism_gid_cnt = entry;
968 	}
969 	if (smcr_indicated(ini->smc_type_v2)) {
970 		memcpy(v2_ext->roce, ini->smcrv2.ib_gid_v2, SMC_GID_SIZE);
971 		v2_ext->max_conns = SMC_CONN_PER_LGR_PREFER;
972 		v2_ext->max_links = SMC_LINKS_PER_LGR_MAX_PREFER;
973 	}
974 
975 	pclc_base->hdr.length = htons(plen);
976 	memcpy(trl->eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
977 
978 	/* send SMC Proposal CLC message */
979 	memset(&msg, 0, sizeof(msg));
980 	i = 0;
981 	vec[i].iov_base = pclc_base;
982 	vec[i++].iov_len = sizeof(*pclc_base);
983 	vec[i].iov_base = pclc_smcd;
984 	vec[i++].iov_len = sizeof(*pclc_smcd);
985 	if (ini->smc_type_v1 != SMC_TYPE_N) {
986 		vec[i].iov_base = pclc_prfx;
987 		vec[i++].iov_len = sizeof(*pclc_prfx);
988 		if (pclc_prfx->ipv6_prefixes_cnt > 0) {
989 			vec[i].iov_base = ipv6_prfx;
990 			vec[i++].iov_len = pclc_prfx->ipv6_prefixes_cnt *
991 					   sizeof(ipv6_prfx[0]);
992 		}
993 	}
994 	if (ini->smc_type_v2 != SMC_TYPE_N) {
995 		vec[i].iov_base = v2_ext;
996 		vec[i++].iov_len = sizeof(*v2_ext) +
997 				   (v2_ext->hdr.eid_cnt * SMC_MAX_EID_LEN);
998 		if (smcd_indicated(ini->smc_type_v2)) {
999 			vec[i].iov_base = smcd_v2_ext;
1000 			vec[i++].iov_len = sizeof(*smcd_v2_ext);
1001 			if (ini->ism_offered_cnt) {
1002 				vec[i].iov_base = gidchids;
1003 				vec[i++].iov_len = v2_ext->hdr.ism_gid_cnt *
1004 					sizeof(struct smc_clc_smcd_gid_chid);
1005 			}
1006 		}
1007 	}
1008 	vec[i].iov_base = trl;
1009 	vec[i++].iov_len = sizeof(*trl);
1010 	/* due to the few bytes needed for clc-handshake this cannot block */
1011 	len = kernel_sendmsg(smc->clcsock, &msg, vec, i, plen);
1012 	if (len < 0) {
1013 		smc->sk.sk_err = smc->clcsock->sk->sk_err;
1014 		reason_code = -smc->sk.sk_err;
1015 	} else if (len < ntohs(pclc_base->hdr.length)) {
1016 		reason_code = -ENETUNREACH;
1017 		smc->sk.sk_err = -reason_code;
1018 	}
1019 
1020 	kfree(pclc);
1021 	return reason_code;
1022 }
1023 
1024 static void
1025 smcd_clc_prep_confirm_accept(struct smc_connection *conn,
1026 			     struct smc_clc_msg_accept_confirm *clc,
1027 			     int first_contact, u8 version,
1028 			     u8 *eid, struct smc_init_info *ini,
1029 			     int *fce_len,
1030 			     struct smc_clc_first_contact_ext_v2x *fce_v2x,
1031 			     struct smc_clc_msg_trail *trl)
1032 {
1033 	struct smcd_dev *smcd = conn->lgr->smcd;
1034 	struct smcd_gid smcd_gid;
1035 	u16 chid;
1036 	int len;
1037 
1038 	/* SMC-D specific settings */
1039 	memcpy(clc->hdr.eyecatcher, SMCD_EYECATCHER,
1040 	       sizeof(SMCD_EYECATCHER));
1041 	smcd->ops->get_local_gid(smcd, &smcd_gid);
1042 	clc->hdr.typev1 = SMC_TYPE_D;
1043 	clc->d0.gid = htonll(smcd_gid.gid);
1044 	clc->d0.token = htonll(conn->rmb_desc->token);
1045 	clc->d0.dmbe_size = conn->rmbe_size_comp;
1046 	clc->d0.dmbe_idx = 0;
1047 	memcpy(&clc->d0.linkid, conn->lgr->id, SMC_LGR_ID_SIZE);
1048 	if (version == SMC_V1) {
1049 		clc->hdr.length = htons(SMCD_CLC_ACCEPT_CONFIRM_LEN);
1050 	} else {
1051 		chid = smc_ism_get_chid(smcd);
1052 		clc->d1.chid = htons(chid);
1053 		if (eid && eid[0])
1054 			memcpy(clc->d1.eid, eid, SMC_MAX_EID_LEN);
1055 		if (__smc_ism_is_virtual(chid))
1056 			clc->d1.gid_ext = htonll(smcd_gid.gid_ext);
1057 		len = SMCD_CLC_ACCEPT_CONFIRM_LEN_V2;
1058 		if (first_contact) {
1059 			*fce_len = smc_clc_fill_fce_v2x(fce_v2x, ini);
1060 			len += *fce_len;
1061 		}
1062 		clc->hdr.length = htons(len);
1063 	}
1064 	memcpy(trl->eyecatcher, SMCD_EYECATCHER,
1065 	       sizeof(SMCD_EYECATCHER));
1066 }
1067 
1068 static void
1069 smcr_clc_prep_confirm_accept(struct smc_connection *conn,
1070 			     struct smc_clc_msg_accept_confirm *clc,
1071 			     int first_contact, u8 version,
1072 			     u8 *eid, struct smc_init_info *ini,
1073 			     int *fce_len,
1074 			     struct smc_clc_first_contact_ext_v2x *fce_v2x,
1075 			     struct smc_clc_fce_gid_ext *gle,
1076 			     struct smc_clc_msg_trail *trl)
1077 {
1078 	struct smc_link *link = conn->lnk;
1079 	int len;
1080 
1081 	/* SMC-R specific settings */
1082 	memcpy(clc->hdr.eyecatcher, SMC_EYECATCHER,
1083 	       sizeof(SMC_EYECATCHER));
1084 	clc->hdr.typev1 = SMC_TYPE_R;
1085 	memcpy(clc->r0.lcl.id_for_peer, local_systemid,
1086 	       sizeof(local_systemid));
1087 	memcpy(&clc->r0.lcl.gid, link->gid, SMC_GID_SIZE);
1088 	memcpy(&clc->r0.lcl.mac, &link->smcibdev->mac[link->ibport - 1],
1089 	       ETH_ALEN);
1090 	hton24(clc->r0.qpn, link->roce_qp->qp_num);
1091 	clc->r0.rmb_rkey =
1092 		htonl(conn->rmb_desc->mr[link->link_idx]->rkey);
1093 	clc->r0.rmbe_idx = 1; /* for now: 1 RMB = 1 RMBE */
1094 	clc->r0.rmbe_alert_token = htonl(conn->alert_token_local);
1095 	switch (clc->hdr.type) {
1096 	case SMC_CLC_ACCEPT:
1097 		clc->r0.qp_mtu = link->path_mtu;
1098 		break;
1099 	case SMC_CLC_CONFIRM:
1100 		clc->r0.qp_mtu = min(link->path_mtu, link->peer_mtu);
1101 		break;
1102 	}
1103 	clc->r0.rmbe_size = conn->rmbe_size_comp;
1104 	clc->r0.rmb_dma_addr = conn->rmb_desc->is_vm ?
1105 		cpu_to_be64((uintptr_t)conn->rmb_desc->cpu_addr) :
1106 		cpu_to_be64((u64)sg_dma_address
1107 			    (conn->rmb_desc->sgt[link->link_idx].sgl));
1108 	hton24(clc->r0.psn, link->psn_initial);
1109 	if (version == SMC_V1) {
1110 		clc->hdr.length = htons(SMCR_CLC_ACCEPT_CONFIRM_LEN);
1111 	} else {
1112 		if (eid && eid[0])
1113 			memcpy(clc->r1.eid, eid, SMC_MAX_EID_LEN);
1114 		len = SMCR_CLC_ACCEPT_CONFIRM_LEN_V2;
1115 		if (first_contact) {
1116 			*fce_len = smc_clc_fill_fce_v2x(fce_v2x, ini);
1117 			len += *fce_len;
1118 			fce_v2x->fce_v2_base.v2_direct =
1119 				!link->lgr->uses_gateway;
1120 			if (clc->hdr.type == SMC_CLC_CONFIRM) {
1121 				memset(gle, 0, sizeof(*gle));
1122 				gle->gid_cnt = ini->smcrv2.gidlist.len;
1123 				len += sizeof(*gle);
1124 				len += gle->gid_cnt * sizeof(gle->gid[0]);
1125 			}
1126 		}
1127 		clc->hdr.length = htons(len);
1128 	}
1129 	memcpy(trl->eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
1130 }
1131 
1132 /* build and send CLC CONFIRM / ACCEPT message */
1133 static int smc_clc_send_confirm_accept(struct smc_sock *smc,
1134 				       struct smc_clc_msg_accept_confirm *clc,
1135 				       int first_contact, u8 version,
1136 				       u8 *eid, struct smc_init_info *ini)
1137 {
1138 	struct smc_clc_first_contact_ext_v2x fce_v2x;
1139 	struct smc_connection *conn = &smc->conn;
1140 	struct smc_clc_fce_gid_ext gle;
1141 	struct smc_clc_msg_trail trl;
1142 	int i, fce_len;
1143 	struct kvec vec[5];
1144 	struct msghdr msg;
1145 
1146 	/* send SMC Confirm CLC msg */
1147 	clc->hdr.version = version;	/* SMC version */
1148 	if (first_contact)
1149 		clc->hdr.typev2 |= SMC_FIRST_CONTACT_MASK;
1150 	if (conn->lgr->is_smcd)
1151 		smcd_clc_prep_confirm_accept(conn, clc, first_contact,
1152 					     version, eid, ini, &fce_len,
1153 					     &fce_v2x, &trl);
1154 	else
1155 		smcr_clc_prep_confirm_accept(conn, clc, first_contact,
1156 					     version, eid, ini, &fce_len,
1157 					     &fce_v2x, &gle, &trl);
1158 	memset(&msg, 0, sizeof(msg));
1159 	i = 0;
1160 	vec[i].iov_base = clc;
1161 	if (version > SMC_V1)
1162 		vec[i++].iov_len = (clc->hdr.typev1 == SMC_TYPE_D ?
1163 					SMCD_CLC_ACCEPT_CONFIRM_LEN_V2 :
1164 					SMCR_CLC_ACCEPT_CONFIRM_LEN_V2) -
1165 				   sizeof(trl);
1166 	else
1167 		vec[i++].iov_len = (clc->hdr.typev1 == SMC_TYPE_D ?
1168 						SMCD_CLC_ACCEPT_CONFIRM_LEN :
1169 						SMCR_CLC_ACCEPT_CONFIRM_LEN) -
1170 				   sizeof(trl);
1171 	if (version > SMC_V1 && first_contact) {
1172 		vec[i].iov_base = &fce_v2x;
1173 		vec[i++].iov_len = fce_len;
1174 		if (!conn->lgr->is_smcd) {
1175 			if (clc->hdr.type == SMC_CLC_CONFIRM) {
1176 				vec[i].iov_base = &gle;
1177 				vec[i++].iov_len = sizeof(gle);
1178 				vec[i].iov_base = &ini->smcrv2.gidlist.list;
1179 				vec[i++].iov_len = gle.gid_cnt *
1180 						   sizeof(gle.gid[0]);
1181 			}
1182 		}
1183 	}
1184 	vec[i].iov_base = &trl;
1185 	vec[i++].iov_len = sizeof(trl);
1186 	return kernel_sendmsg(smc->clcsock, &msg, vec, 1,
1187 			      ntohs(clc->hdr.length));
1188 }
1189 
1190 /* send CLC CONFIRM message across internal TCP socket */
1191 int smc_clc_send_confirm(struct smc_sock *smc, bool clnt_first_contact,
1192 			 u8 version, u8 *eid, struct smc_init_info *ini)
1193 {
1194 	struct smc_clc_msg_accept_confirm cclc;
1195 	int reason_code = 0;
1196 	int len;
1197 
1198 	/* send SMC Confirm CLC msg */
1199 	memset(&cclc, 0, sizeof(cclc));
1200 	cclc.hdr.type = SMC_CLC_CONFIRM;
1201 	len = smc_clc_send_confirm_accept(smc, &cclc, clnt_first_contact,
1202 					  version, eid, ini);
1203 	if (len < ntohs(cclc.hdr.length)) {
1204 		if (len >= 0) {
1205 			reason_code = -ENETUNREACH;
1206 			smc->sk.sk_err = -reason_code;
1207 		} else {
1208 			smc->sk.sk_err = smc->clcsock->sk->sk_err;
1209 			reason_code = -smc->sk.sk_err;
1210 		}
1211 	}
1212 	return reason_code;
1213 }
1214 
1215 /* send CLC ACCEPT message across internal TCP socket */
1216 int smc_clc_send_accept(struct smc_sock *new_smc, bool srv_first_contact,
1217 			u8 version, u8 *negotiated_eid, struct smc_init_info *ini)
1218 {
1219 	struct smc_clc_msg_accept_confirm aclc;
1220 	int len;
1221 
1222 	memset(&aclc, 0, sizeof(aclc));
1223 	aclc.hdr.type = SMC_CLC_ACCEPT;
1224 	len = smc_clc_send_confirm_accept(new_smc, &aclc, srv_first_contact,
1225 					  version, negotiated_eid, ini);
1226 	if (len < ntohs(aclc.hdr.length))
1227 		len = len >= 0 ? -EPROTO : -new_smc->clcsock->sk->sk_err;
1228 
1229 	return len > 0 ? 0 : len;
1230 }
1231 
1232 int smc_clc_srv_v2x_features_validate(struct smc_clc_msg_proposal *pclc,
1233 				      struct smc_init_info *ini)
1234 {
1235 	struct smc_clc_v2_extension *pclc_v2_ext;
1236 
1237 	ini->max_conns = SMC_CONN_PER_LGR_MAX;
1238 	ini->max_links = SMC_LINKS_ADD_LNK_MAX;
1239 
1240 	if ((!(ini->smcd_version & SMC_V2) && !(ini->smcr_version & SMC_V2)) ||
1241 	    ini->release_nr < SMC_RELEASE_1)
1242 		return 0;
1243 
1244 	pclc_v2_ext = smc_get_clc_v2_ext(pclc);
1245 	if (!pclc_v2_ext)
1246 		return SMC_CLC_DECL_NOV2EXT;
1247 
1248 	if (ini->smcr_version & SMC_V2) {
1249 		ini->max_conns = min_t(u8, pclc_v2_ext->max_conns, SMC_CONN_PER_LGR_PREFER);
1250 		if (ini->max_conns < SMC_CONN_PER_LGR_MIN)
1251 			return SMC_CLC_DECL_MAXCONNERR;
1252 
1253 		ini->max_links = min_t(u8, pclc_v2_ext->max_links, SMC_LINKS_PER_LGR_MAX_PREFER);
1254 		if (ini->max_links < SMC_LINKS_ADD_LNK_MIN)
1255 			return SMC_CLC_DECL_MAXLINKERR;
1256 	}
1257 
1258 	return 0;
1259 }
1260 
1261 int smc_clc_clnt_v2x_features_validate(struct smc_clc_first_contact_ext *fce,
1262 				       struct smc_init_info *ini)
1263 {
1264 	struct smc_clc_first_contact_ext_v2x *fce_v2x =
1265 		(struct smc_clc_first_contact_ext_v2x *)fce;
1266 
1267 	if (ini->release_nr < SMC_RELEASE_1)
1268 		return 0;
1269 
1270 	if (!ini->is_smcd) {
1271 		if (fce_v2x->max_conns < SMC_CONN_PER_LGR_MIN)
1272 			return SMC_CLC_DECL_MAXCONNERR;
1273 		ini->max_conns = fce_v2x->max_conns;
1274 
1275 		if (fce_v2x->max_links > SMC_LINKS_ADD_LNK_MAX ||
1276 		    fce_v2x->max_links < SMC_LINKS_ADD_LNK_MIN)
1277 			return SMC_CLC_DECL_MAXLINKERR;
1278 		ini->max_links = fce_v2x->max_links;
1279 	}
1280 
1281 	return 0;
1282 }
1283 
1284 int smc_clc_v2x_features_confirm_check(struct smc_clc_msg_accept_confirm *cclc,
1285 				       struct smc_init_info *ini)
1286 {
1287 	struct smc_clc_first_contact_ext *fce =
1288 		smc_get_clc_first_contact_ext(cclc, ini->is_smcd);
1289 	struct smc_clc_first_contact_ext_v2x *fce_v2x =
1290 		(struct smc_clc_first_contact_ext_v2x *)fce;
1291 
1292 	if (cclc->hdr.version == SMC_V1 ||
1293 	    !(cclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK))
1294 		return 0;
1295 
1296 	if (ini->release_nr != fce->release)
1297 		return SMC_CLC_DECL_RELEASEERR;
1298 
1299 	if (fce->release < SMC_RELEASE_1)
1300 		return 0;
1301 
1302 	if (!ini->is_smcd) {
1303 		if (fce_v2x->max_conns != ini->max_conns)
1304 			return SMC_CLC_DECL_MAXCONNERR;
1305 		if (fce_v2x->max_links != ini->max_links)
1306 			return SMC_CLC_DECL_MAXLINKERR;
1307 	}
1308 
1309 	return 0;
1310 }
1311 
1312 void smc_clc_get_hostname(u8 **host)
1313 {
1314 	*host = &smc_hostname[0];
1315 }
1316 
1317 void __init smc_clc_init(void)
1318 {
1319 	struct new_utsname *u;
1320 
1321 	memset(smc_hostname, _S, sizeof(smc_hostname)); /* ASCII blanks */
1322 	u = utsname();
1323 	memcpy(smc_hostname, u->nodename,
1324 	       min_t(size_t, strlen(u->nodename), sizeof(smc_hostname)));
1325 
1326 	INIT_LIST_HEAD(&smc_clc_eid_table.list);
1327 	rwlock_init(&smc_clc_eid_table.lock);
1328 	smc_clc_eid_table.ueid_cnt = 0;
1329 #if IS_ENABLED(CONFIG_S390)
1330 	smc_clc_eid_table.seid_enabled = 1;
1331 #else
1332 	smc_clc_eid_table.seid_enabled = 0;
1333 #endif
1334 }
1335 
1336 void smc_clc_exit(void)
1337 {
1338 	smc_clc_ueid_remove(NULL);
1339 }
1340