net/smc/smc_clc.c

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