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         kernel_getsockname(clcsock, (struct sockaddr *)&addrs);
 234         /* analyze IP specific data of net_device belonging to TCP socket */
 235         addr6 = (struct sockaddr_in6 *)&addrs;
 236         rcu_read_lock();
 237         if (addrs.ss_family == PF_INET) {
 238                 /* IPv4 */
 239                 addr = (struct sockaddr_in *)&addrs;
 240                 rc = smc_clc_prfx_set4_rcu(dst, addr->sin_addr.s_addr, prop);
 241         } else if (ipv6_addr_v4mapped(&addr6->sin6_addr)) {
 242                 /* mapped IPv4 address - peer is IPv4 only */
 243                 rc = smc_clc_prfx_set4_rcu(dst, addr6->sin6_addr.s6_addr32[3],
 244                                            prop);
 245         } else {
 246                 /* IPv6 */
 247                 rc = smc_clc_prfx_set6_rcu(dst, prop, ipv6_prfx);
 248         }
 249         rcu_read_unlock();
 250 out_rel:
 251         dst_release(dst);
 252 out:
 253         return rc;
 254 }
 255
 256 /* match ipv4 addrs of dev against addr in CLC proposal */
 257 static int smc_clc_prfx_match4_rcu(struct net_device *dev,
 258                                    struct smc_clc_msg_proposal_prefix *prop)
 259 {
 260         struct in_device *in_dev = __in_dev_get_rcu(dev);
 261         const struct in_ifaddr *ifa;
 262
 263         if (!in_dev)
 264                 return -ENODEV;
 265         in_dev_for_each_ifa_rcu(ifa, in_dev) {
 266                 if (prop->prefix_len == inet_mask_len(ifa->ifa_mask) &&
 267                     inet_ifa_match(prop->outgoing_subnet, ifa))
 268                         return 0;
 269         }
 270
 271         return -ENOENT;
 272 }
 273
 274 /* match ipv6 addrs of dev against addrs in CLC proposal */
 275 static int smc_clc_prfx_match6_rcu(struct net_device *dev,
 276                                    struct smc_clc_msg_proposal_prefix *prop)
 277 {
 278 #if IS_ENABLED(CONFIG_IPV6)
 279         struct inet6_dev *in6_dev = __in6_dev_get(dev);
 280         struct smc_clc_ipv6_prefix *ipv6_prfx;
 281         struct inet6_ifaddr *ifa;
 282         int i, max;
 283
 284         if (!in6_dev)
 285                 return -ENODEV;
 286         /* ipv6 prefix list starts behind smc_clc_msg_proposal_prefix */
 287         ipv6_prfx = (struct smc_clc_ipv6_prefix *)((u8 *)prop + sizeof(*prop));
 288         max = min_t(u8, prop->ipv6_prefixes_cnt, SMC_CLC_MAX_V6_PREFIX);
 289         list_for_each_entry(ifa, &in6_dev->addr_list, if_list) {
 290                 if (ipv6_addr_type(&ifa->addr) & IPV6_ADDR_LINKLOCAL)
 291                         continue;
 292                 for (i = 0; i < max; i++) {
 293                         if (ifa->prefix_len == ipv6_prfx[i].prefix_len &&
 294                             ipv6_prefix_equal(&ifa->addr, &ipv6_prfx[i].prefix,
 295                                               ifa->prefix_len))
 296                                 return 0;
 297                 }
 298         }
 299 #endif
 300         return -ENOENT;
 301 }
 302
 303 /* check if proposed prefixes match one of our device prefixes */
 304 int smc_clc_prfx_match(struct socket *clcsock,
 305                        struct smc_clc_msg_proposal_prefix *prop)
 306 {
 307         struct dst_entry *dst = sk_dst_get(clcsock->sk);
 308         int rc;
 309
 310         if (!dst) {
 311                 rc = -ENOTCONN;
 312                 goto out;
 313         }
 314         if (!dst->dev) {
 315                 rc = -ENODEV;
 316                 goto out_rel;
 317         }
 318         rcu_read_lock();
 319         if (!prop->ipv6_prefixes_cnt)
 320                 rc = smc_clc_prfx_match4_rcu(dst->dev, prop);
 321         else
 322                 rc = smc_clc_prfx_match6_rcu(dst->dev, prop);
 323         rcu_read_unlock();
 324 out_rel:
 325         dst_release(dst);
 326 out:
 327         return rc;
 328 }
 329
 330 /* Wait for data on the tcp-socket, analyze received data
 331  * Returns:
 332  * 0 if success and it was not a decline that we received.
 333  * SMC_CLC_DECL_REPLY if decline received for fallback w/o another decl send.
 334  * clcsock error, -EINTR, -ECONNRESET, -EPROTO otherwise.
 335  */
 336 int smc_clc_wait_msg(struct smc_sock *smc, void *buf, int buflen,
 337                      u8 expected_type, unsigned long timeout)
 338 {
 339         long rcvtimeo = smc->clcsock->sk->sk_rcvtimeo;
 340         struct sock *clc_sk = smc->clcsock->sk;
 341         struct smc_clc_msg_hdr *clcm = buf;
 342         struct msghdr msg = {NULL, 0};
 343         int reason_code = 0;
 344         struct kvec vec = {buf, buflen};
 345         int len, datlen, recvlen;
 346         bool check_trl = true;
 347         int krflags;
 348
 349         /* peek the first few bytes to determine length of data to receive
 350          * so we don't consume any subsequent CLC message or payload data
 351          * in the TCP byte stream
 352          */
 353         /*
 354          * Caller must make sure that buflen is no less than
 355          * sizeof(struct smc_clc_msg_hdr)
 356          */
 357         krflags = MSG_PEEK | MSG_WAITALL;
 358         clc_sk->sk_rcvtimeo = timeout;
 359         iov_iter_kvec(&msg.msg_iter, READ, &vec, 1,
 360                         sizeof(struct smc_clc_msg_hdr));
 361         len = sock_recvmsg(smc->clcsock, &msg, krflags);
 362         if (signal_pending(current)) {
 363                 reason_code = -EINTR;
 364                 clc_sk->sk_err = EINTR;
 365                 smc->sk.sk_err = EINTR;
 366                 goto out;
 367         }
 368         if (clc_sk->sk_err) {
 369                 reason_code = -clc_sk->sk_err;
 370                 if (clc_sk->sk_err == EAGAIN &&
 371                     expected_type == SMC_CLC_DECLINE)
 372                         clc_sk->sk_err = 0; /* reset for fallback usage */
 373                 else
 374                         smc->sk.sk_err = clc_sk->sk_err;
 375                 goto out;
 376         }
 377         if (!len) { /* peer has performed orderly shutdown */
 378                 smc->sk.sk_err = ECONNRESET;
 379                 reason_code = -ECONNRESET;
 380                 goto out;
 381         }
 382         if (len < 0) {
 383                 if (len != -EAGAIN || expected_type != SMC_CLC_DECLINE)
 384                         smc->sk.sk_err = -len;
 385                 reason_code = len;
 386                 goto out;
 387         }
 388         datlen = ntohs(clcm->length);
 389         if ((len < sizeof(struct smc_clc_msg_hdr)) ||
 390             (clcm->version < SMC_V1) ||
 391             ((clcm->type != SMC_CLC_DECLINE) &&
 392              (clcm->type != expected_type))) {
 393                 smc->sk.sk_err = EPROTO;
 394                 reason_code = -EPROTO;
 395                 goto out;
 396         }
 397
 398         /* receive the complete CLC message */
 399         memset(&msg, 0, sizeof(struct msghdr));
 400         if (datlen > buflen) {
 401                 check_trl = false;
 402                 recvlen = buflen;
 403         } else {
 404                 recvlen = datlen;
 405         }
 406         iov_iter_kvec(&msg.msg_iter, READ, &vec, 1, recvlen);
 407         krflags = MSG_WAITALL;
 408         len = sock_recvmsg(smc->clcsock, &msg, krflags);
 409         if (len < recvlen || !smc_clc_msg_hdr_valid(clcm, check_trl)) {
 410                 smc->sk.sk_err = EPROTO;
 411                 reason_code = -EPROTO;
 412                 goto out;
 413         }
 414         datlen -= len;
 415         while (datlen) {
 416                 u8 tmp[SMC_CLC_RECV_BUF_LEN];
 417
 418                 vec.iov_base = &tmp;
 419                 vec.iov_len = SMC_CLC_RECV_BUF_LEN;
 420                 /* receive remaining proposal message */
 421                 recvlen = datlen > SMC_CLC_RECV_BUF_LEN ?
 422                                                 SMC_CLC_RECV_BUF_LEN : datlen;
 423                 iov_iter_kvec(&msg.msg_iter, READ, &vec, 1, recvlen);
 424                 len = sock_recvmsg(smc->clcsock, &msg, krflags);
 425                 datlen -= len;
 426         }
 427         if (clcm->type == SMC_CLC_DECLINE) {
 428                 struct smc_clc_msg_decline *dclc;
 429
 430                 dclc = (struct smc_clc_msg_decline *)clcm;
 431                 reason_code = SMC_CLC_DECL_PEERDECL;
 432                 smc->peer_diagnosis = ntohl(dclc->peer_diagnosis);
 433                 if (((struct smc_clc_msg_decline *)buf)->hdr.typev2 &
 434                                                 SMC_FIRST_CONTACT_MASK) {
 435                         smc->conn.lgr->sync_err = 1;
 436                         smc_lgr_terminate_sched(smc->conn.lgr);
 437                 }
 438         }
 439
 440 out:
 441         clc_sk->sk_rcvtimeo = rcvtimeo;
 442         return reason_code;
 443 }
 444
 445 /* send CLC DECLINE message across internal TCP socket */
 446 int smc_clc_send_decline(struct smc_sock *smc, u32 peer_diag_info, u8 version)
 447 {
 448         struct smc_clc_msg_decline dclc;
 449         struct msghdr msg;
 450         struct kvec vec;
 451         int len;
 452
 453         memset(&dclc, 0, sizeof(dclc));
 454         memcpy(dclc.hdr.eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
 455         dclc.hdr.type = SMC_CLC_DECLINE;
 456         dclc.hdr.length = htons(sizeof(struct smc_clc_msg_decline));
 457         dclc.hdr.version = version;
 458         dclc.os_type = version == SMC_V1 ? 0 : SMC_CLC_OS_LINUX;
 459         dclc.hdr.typev2 = (peer_diag_info == SMC_CLC_DECL_SYNCERR) ?
 460                                                 SMC_FIRST_CONTACT_MASK : 0;
 461         if ((!smc->conn.lgr || !smc->conn.lgr->is_smcd) &&
 462             smc_ib_is_valid_local_systemid())
 463                 memcpy(dclc.id_for_peer, local_systemid,
 464                        sizeof(local_systemid));
 465         dclc.peer_diagnosis = htonl(peer_diag_info);
 466         memcpy(dclc.trl.eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
 467
 468         memset(&msg, 0, sizeof(msg));
 469         vec.iov_base = &dclc;
 470         vec.iov_len = sizeof(struct smc_clc_msg_decline);
 471         len = kernel_sendmsg(smc->clcsock, &msg, &vec, 1,
 472                              sizeof(struct smc_clc_msg_decline));
 473         if (len < 0 || len < sizeof(struct smc_clc_msg_decline))
 474                 len = -EPROTO;
 475         return len > 0 ? 0 : len;
 476 }
 477
 478 /* send CLC PROPOSAL message across internal TCP socket */
 479 int smc_clc_send_proposal(struct smc_sock *smc, struct smc_init_info *ini)
 480 {
 481         struct smc_clc_smcd_v2_extension *smcd_v2_ext;
 482         struct smc_clc_msg_proposal_prefix *pclc_prfx;
 483         struct smc_clc_msg_proposal *pclc_base;
 484         struct smc_clc_smcd_gid_chid *gidchids;
 485         struct smc_clc_msg_proposal_area *pclc;
 486         struct smc_clc_ipv6_prefix *ipv6_prfx;
 487         struct smc_clc_v2_extension *v2_ext;
 488         struct smc_clc_msg_smcd *pclc_smcd;
 489         struct smc_clc_msg_trail *trl;
 490         int len, i, plen, rc;
 491         int reason_code = 0;
 492         struct kvec vec[8];
 493         struct msghdr msg;
 494
 495         pclc = kzalloc(sizeof(*pclc), GFP_KERNEL);
 496         if (!pclc)
 497                 return -ENOMEM;
 498
 499         pclc_base = &pclc->pclc_base;
 500         pclc_smcd = &pclc->pclc_smcd;
 501         pclc_prfx = &pclc->pclc_prfx;
 502         ipv6_prfx = pclc->pclc_prfx_ipv6;
 503         v2_ext = &pclc->pclc_v2_ext;
 504         smcd_v2_ext = &pclc->pclc_smcd_v2_ext;
 505         gidchids = pclc->pclc_gidchids;
 506         trl = &pclc->pclc_trl;
 507
 508         pclc_base->hdr.version = SMC_V2;
 509         pclc_base->hdr.typev1 = ini->smc_type_v1;
 510         pclc_base->hdr.typev2 = ini->smc_type_v2;
 511         plen = sizeof(*pclc_base) + sizeof(*pclc_smcd) + sizeof(*trl);
 512
 513         /* retrieve ip prefixes for CLC proposal msg */
 514         if (ini->smc_type_v1 != SMC_TYPE_N) {
 515                 rc = smc_clc_prfx_set(smc->clcsock, pclc_prfx, ipv6_prfx);
 516                 if (rc) {
 517                         if (ini->smc_type_v2 == SMC_TYPE_N) {
 518                                 kfree(pclc);
 519                                 return SMC_CLC_DECL_CNFERR;
 520                         }
 521                         pclc_base->hdr.typev1 = SMC_TYPE_N;
 522                 } else {
 523                         pclc_base->iparea_offset = htons(sizeof(*pclc_smcd));
 524                         plen += sizeof(*pclc_prfx) +
 525                                         pclc_prfx->ipv6_prefixes_cnt *
 526                                         sizeof(ipv6_prfx[0]);
 527                 }
 528         }
 529
 530         /* build SMC Proposal CLC message */
 531         memcpy(pclc_base->hdr.eyecatcher, SMC_EYECATCHER,
 532                sizeof(SMC_EYECATCHER));
 533         pclc_base->hdr.type = SMC_CLC_PROPOSAL;
 534         if (smcr_indicated(ini->smc_type_v1)) {
 535                 /* add SMC-R specifics */
 536                 memcpy(pclc_base->lcl.id_for_peer, local_systemid,
 537                        sizeof(local_systemid));
 538                 memcpy(pclc_base->lcl.gid, ini->ib_gid, SMC_GID_SIZE);
 539                 memcpy(pclc_base->lcl.mac, &ini->ib_dev->mac[ini->ib_port - 1],
 540                        ETH_ALEN);
 541         }
 542         if (smcd_indicated(ini->smc_type_v1)) {
 543                 /* add SMC-D specifics */
 544                 if (ini->ism_dev[0]) {
 545                         pclc_smcd->ism.gid = htonll(ini->ism_dev[0]->local_gid);
 546                         pclc_smcd->ism.chid =
 547                                 htons(smc_ism_get_chid(ini->ism_dev[0]));
 548                 }
 549         }
 550         if (ini->smc_type_v2 == SMC_TYPE_N) {
 551                 pclc_smcd->v2_ext_offset = 0;
 552         } else {
 553                 u16 v2_ext_offset;
 554                 u8 *eid = NULL;
 555
 556                 v2_ext_offset = sizeof(*pclc_smcd) -
 557                         offsetofend(struct smc_clc_msg_smcd, v2_ext_offset);
 558                 if (ini->smc_type_v1 != SMC_TYPE_N)
 559                         v2_ext_offset += sizeof(*pclc_prfx) +
 560                                                 pclc_prfx->ipv6_prefixes_cnt *
 561                                                 sizeof(ipv6_prfx[0]);
 562                 pclc_smcd->v2_ext_offset = htons(v2_ext_offset);
 563                 v2_ext->hdr.eid_cnt = 0;
 564                 v2_ext->hdr.ism_gid_cnt = ini->ism_offered_cnt;
 565                 v2_ext->hdr.flag.release = SMC_RELEASE;
 566                 v2_ext->hdr.flag.seid = 1;
 567                 v2_ext->hdr.smcd_v2_ext_offset = htons(sizeof(*v2_ext) -
 568                                 offsetofend(struct smc_clnt_opts_area_hdr,
 569                                             smcd_v2_ext_offset) +
 570                                 v2_ext->hdr.eid_cnt * SMC_MAX_EID_LEN);
 571                 if (ini->ism_dev[0])
 572                         smc_ism_get_system_eid(ini->ism_dev[0], &eid);
 573                 else
 574                         smc_ism_get_system_eid(ini->ism_dev[1], &eid);
 575                 if (eid)
 576                         memcpy(smcd_v2_ext->system_eid, eid, SMC_MAX_EID_LEN);
 577                 plen += sizeof(*v2_ext) + sizeof(*smcd_v2_ext);
 578                 if (ini->ism_offered_cnt) {
 579                         for (i = 1; i <= ini->ism_offered_cnt; i++) {
 580                                 gidchids[i - 1].gid =
 581                                         htonll(ini->ism_dev[i]->local_gid);
 582                                 gidchids[i - 1].chid =
 583                                         htons(smc_ism_get_chid(ini->ism_dev[i]));
 584                         }
 585                         plen += ini->ism_offered_cnt *
 586                                 sizeof(struct smc_clc_smcd_gid_chid);
 587                 }
 588         }
 589         pclc_base->hdr.length = htons(plen);
 590         memcpy(trl->eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
 591
 592         /* send SMC Proposal CLC message */
 593         memset(&msg, 0, sizeof(msg));
 594         i = 0;
 595         vec[i].iov_base = pclc_base;
 596         vec[i++].iov_len = sizeof(*pclc_base);
 597         vec[i].iov_base = pclc_smcd;
 598         vec[i++].iov_len = sizeof(*pclc_smcd);
 599         if (ini->smc_type_v1 != SMC_TYPE_N) {
 600                 vec[i].iov_base = pclc_prfx;
 601                 vec[i++].iov_len = sizeof(*pclc_prfx);
 602                 if (pclc_prfx->ipv6_prefixes_cnt > 0) {
 603                         vec[i].iov_base = ipv6_prfx;
 604                         vec[i++].iov_len = pclc_prfx->ipv6_prefixes_cnt *
 605                                            sizeof(ipv6_prfx[0]);
 606                 }
 607         }
 608         if (ini->smc_type_v2 != SMC_TYPE_N) {
 609                 vec[i].iov_base = v2_ext;
 610                 vec[i++].iov_len = sizeof(*v2_ext);
 611                 vec[i].iov_base = smcd_v2_ext;
 612                 vec[i++].iov_len = sizeof(*smcd_v2_ext);
 613                 if (ini->ism_offered_cnt) {
 614                         vec[i].iov_base = gidchids;
 615                         vec[i++].iov_len = ini->ism_offered_cnt *
 616                                         sizeof(struct smc_clc_smcd_gid_chid);
 617                 }
 618         }
 619         vec[i].iov_base = trl;
 620         vec[i++].iov_len = sizeof(*trl);
 621         /* due to the few bytes needed for clc-handshake this cannot block */
 622         len = kernel_sendmsg(smc->clcsock, &msg, vec, i, plen);
 623         if (len < 0) {
 624                 smc->sk.sk_err = smc->clcsock->sk->sk_err;
 625                 reason_code = -smc->sk.sk_err;
 626         } else if (len < ntohs(pclc_base->hdr.length)) {
 627                 reason_code = -ENETUNREACH;
 628                 smc->sk.sk_err = -reason_code;
 629         }
 630
 631         kfree(pclc);
 632         return reason_code;
 633 }
 634
 635 /* build and send CLC CONFIRM / ACCEPT message */
 636 static int smc_clc_send_confirm_accept(struct smc_sock *smc,
 637                                        struct smc_clc_msg_accept_confirm_v2 *clc_v2,
 638                                        int first_contact, u8 version)
 639 {
 640         struct smc_connection *conn = &smc->conn;
 641         struct smc_clc_msg_accept_confirm *clc;
 642         struct smc_clc_first_contact_ext fce;
 643         struct smc_clc_msg_trail trl;
 644         struct kvec vec[3];
 645         struct msghdr msg;
 646         int i, len;
 647
 648         /* send SMC Confirm CLC msg */
 649         clc = (struct smc_clc_msg_accept_confirm *)clc_v2;
 650         clc->hdr.version = version;     /* SMC version */
 651         if (first_contact)
 652                 clc->hdr.typev2 |= SMC_FIRST_CONTACT_MASK;
 653         if (conn->lgr->is_smcd) {
 654                 /* SMC-D specific settings */
 655                 memcpy(clc->hdr.eyecatcher, SMCD_EYECATCHER,
 656                        sizeof(SMCD_EYECATCHER));
 657                 clc->hdr.typev1 = SMC_TYPE_D;
 658                 clc->d0.gid = conn->lgr->smcd->local_gid;
 659                 clc->d0.token = conn->rmb_desc->token;
 660                 clc->d0.dmbe_size = conn->rmbe_size_short;
 661                 clc->d0.dmbe_idx = 0;
 662                 memcpy(&clc->d0.linkid, conn->lgr->id, SMC_LGR_ID_SIZE);
 663                 if (version == SMC_V1) {
 664                         clc->hdr.length = htons(SMCD_CLC_ACCEPT_CONFIRM_LEN);
 665                 } else {
 666                         u8 *eid = NULL;
 667
 668                         clc_v2->chid = htons(smc_ism_get_chid(conn->lgr->smcd));
 669                         smc_ism_get_system_eid(conn->lgr->smcd, &eid);
 670                         if (eid)
 671                                 memcpy(clc_v2->eid, eid, SMC_MAX_EID_LEN);
 672                         len = SMCD_CLC_ACCEPT_CONFIRM_LEN_V2;
 673                         if (first_contact)
 674                                 smc_clc_fill_fce(&fce, &len);
 675                         clc_v2->hdr.length = htons(len);
 676                 }
 677                 memcpy(trl.eyecatcher, SMCD_EYECATCHER,
 678                        sizeof(SMCD_EYECATCHER));
 679         } else {
 680                 struct smc_link *link = conn->lnk;
 681
 682                 /* SMC-R specific settings */
 683                 link = conn->lnk;
 684                 memcpy(clc->hdr.eyecatcher, SMC_EYECATCHER,
 685                        sizeof(SMC_EYECATCHER));
 686                 clc->hdr.typev1 = SMC_TYPE_R;
 687                 clc->hdr.length = htons(SMCR_CLC_ACCEPT_CONFIRM_LEN);
 688                 memcpy(clc->r0.lcl.id_for_peer, local_systemid,
 689                        sizeof(local_systemid));
 690                 memcpy(&clc->r0.lcl.gid, link->gid, SMC_GID_SIZE);
 691                 memcpy(&clc->r0.lcl.mac, &link->smcibdev->mac[link->ibport - 1],
 692                        ETH_ALEN);
 693                 hton24(clc->r0.qpn, link->roce_qp->qp_num);
 694                 clc->r0.rmb_rkey =
 695                         htonl(conn->rmb_desc->mr_rx[link->link_idx]->rkey);
 696                 clc->r0.rmbe_idx = 1; /* for now: 1 RMB = 1 RMBE */
 697                 clc->r0.rmbe_alert_token = htonl(conn->alert_token_local);
 698                 switch (clc->hdr.type) {
 699                 case SMC_CLC_ACCEPT:
 700                         clc->r0.qp_mtu = link->path_mtu;
 701                         break;
 702                 case SMC_CLC_CONFIRM:
 703                         clc->r0.qp_mtu = min(link->path_mtu, link->peer_mtu);
 704                         break;
 705                 }
 706                 clc->r0.rmbe_size = conn->rmbe_size_short;
 707                 clc->r0.rmb_dma_addr = cpu_to_be64((u64)sg_dma_address
 708                                 (conn->rmb_desc->sgt[link->link_idx].sgl));
 709                 hton24(clc->r0.psn, link->psn_initial);
 710                 memcpy(trl.eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER));
 711         }
 712
 713         memset(&msg, 0, sizeof(msg));
 714         i = 0;
 715         vec[i].iov_base = clc_v2;
 716         if (version > SMC_V1)
 717                 vec[i++].iov_len = SMCD_CLC_ACCEPT_CONFIRM_LEN_V2 - sizeof(trl);
 718         else
 719                 vec[i++].iov_len = (clc->hdr.typev1 == SMC_TYPE_D ?
 720                                                 SMCD_CLC_ACCEPT_CONFIRM_LEN :
 721                                                 SMCR_CLC_ACCEPT_CONFIRM_LEN) -
 722                                    sizeof(trl);
 723         if (version > SMC_V1 && first_contact) {
 724                 vec[i].iov_base = &fce;
 725                 vec[i++].iov_len = sizeof(fce);
 726         }
 727         vec[i].iov_base = &trl;
 728         vec[i++].iov_len = sizeof(trl);
 729         return kernel_sendmsg(smc->clcsock, &msg, vec, 1,
 730                               ntohs(clc->hdr.length));
 731 }
 732
 733 /* send CLC CONFIRM message across internal TCP socket */
 734 int smc_clc_send_confirm(struct smc_sock *smc, bool clnt_first_contact,
 735                          u8 version)
 736 {
 737         struct smc_clc_msg_accept_confirm_v2 cclc_v2;
 738         int reason_code = 0;
 739         int len;
 740
 741         /* send SMC Confirm CLC msg */
 742         memset(&cclc_v2, 0, sizeof(cclc_v2));
 743         cclc_v2.hdr.type = SMC_CLC_CONFIRM;
 744         len = smc_clc_send_confirm_accept(smc, &cclc_v2, clnt_first_contact,
 745                                           version);
 746         if (len < ntohs(cclc_v2.hdr.length)) {
 747                 if (len >= 0) {
 748                         reason_code = -ENETUNREACH;
 749                         smc->sk.sk_err = -reason_code;
 750                 } else {
 751                         smc->sk.sk_err = smc->clcsock->sk->sk_err;
 752                         reason_code = -smc->sk.sk_err;
 753                 }
 754         }
 755         return reason_code;
 756 }
 757
 758 /* send CLC ACCEPT message across internal TCP socket */
 759 int smc_clc_send_accept(struct smc_sock *new_smc, bool srv_first_contact,
 760                         u8 version)
 761 {
 762         struct smc_clc_msg_accept_confirm_v2 aclc_v2;
 763         int len;
 764
 765         memset(&aclc_v2, 0, sizeof(aclc_v2));
 766         aclc_v2.hdr.type = SMC_CLC_ACCEPT;
 767         len = smc_clc_send_confirm_accept(new_smc, &aclc_v2, srv_first_contact,
 768                                           version);
 769         if (len < ntohs(aclc_v2.hdr.length))
 770                 len = len >= 0 ? -EPROTO : -new_smc->clcsock->sk->sk_err;
 771
 772         return len > 0 ? 0 : len;
 773 }
 774
 775 void smc_clc_get_hostname(u8 **host)
 776 {
 777         *host = &smc_hostname[0];
 778 }
 779
 780 void __init smc_clc_init(void)
 781 {
 782         struct new_utsname *u;
 783
 784         memset(smc_hostname, _S, sizeof(smc_hostname)); /* ASCII blanks */
 785         u = utsname();
 786         memcpy(smc_hostname, u->nodename,
 787                min_t(size_t, strlen(u->nodename), sizeof(smc_hostname)));
 788 }