Richard Alpe | bfb3e5d | 2015-02-09 09:50:03 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (c) 2014, Ericsson AB |
| 3 | * All rights reserved. |
| 4 | * |
| 5 | * Redistribution and use in source and binary forms, with or without |
| 6 | * modification, are permitted provided that the following conditions are met: |
| 7 | * |
| 8 | * 1. Redistributions of source code must retain the above copyright |
| 9 | * notice, this list of conditions and the following disclaimer. |
| 10 | * 2. Redistributions in binary form must reproduce the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer in the |
| 12 | * documentation and/or other materials provided with the distribution. |
| 13 | * 3. Neither the names of the copyright holders nor the names of its |
| 14 | * contributors may be used to endorse or promote products derived from |
| 15 | * this software without specific prior written permission. |
| 16 | * |
| 17 | * Alternatively, this software may be distributed under the terms of the |
| 18 | * GNU General Public License ("GPL") version 2 as published by the Free |
| 19 | * Software Foundation. |
| 20 | * |
| 21 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
| 22 | * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 23 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 24 | * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE |
| 25 | * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| 26 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| 27 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| 28 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| 29 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| 30 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| 31 | * POSSIBILITY OF SUCH DAMAGE. |
| 32 | */ |
| 33 | |
| 34 | #include "core.h" |
| 35 | #include "config.h" |
Richard Alpe | d0796d1 | 2015-02-09 09:50:04 +0100 | [diff] [blame^] | 36 | #include "bearer.h" |
Richard Alpe | bfb3e5d | 2015-02-09 09:50:03 +0100 | [diff] [blame] | 37 | #include <net/genetlink.h> |
| 38 | #include <linux/tipc_config.h> |
| 39 | |
Richard Alpe | d0796d1 | 2015-02-09 09:50:04 +0100 | [diff] [blame^] | 40 | /* The legacy API had an artificial message length limit called |
| 41 | * ULTRA_STRING_MAX_LEN. |
| 42 | */ |
| 43 | #define ULTRA_STRING_MAX_LEN 32768 |
| 44 | |
| 45 | #define TIPC_SKB_MAX TLV_SPACE(ULTRA_STRING_MAX_LEN) |
| 46 | |
| 47 | #define REPLY_TRUNCATED "<truncated>\n" |
| 48 | |
| 49 | struct tipc_nl_compat_msg { |
| 50 | u16 cmd; |
| 51 | int rep_size; |
| 52 | struct sk_buff *rep; |
| 53 | struct tlv_desc *req; |
| 54 | struct sock *dst_sk; |
| 55 | }; |
| 56 | |
| 57 | struct tipc_nl_compat_cmd_dump { |
| 58 | int (*dumpit)(struct sk_buff *, struct netlink_callback *); |
| 59 | int (*format)(struct tipc_nl_compat_msg *msg, struct nlattr **attrs); |
| 60 | }; |
| 61 | |
| 62 | static int tipc_skb_tailroom(struct sk_buff *skb) |
| 63 | { |
| 64 | int tailroom; |
| 65 | int limit; |
| 66 | |
| 67 | tailroom = skb_tailroom(skb); |
| 68 | limit = TIPC_SKB_MAX - skb->len; |
| 69 | |
| 70 | if (tailroom < limit) |
| 71 | return tailroom; |
| 72 | |
| 73 | return limit; |
| 74 | } |
| 75 | |
| 76 | static int tipc_add_tlv(struct sk_buff *skb, u16 type, void *data, u16 len) |
| 77 | { |
| 78 | struct tlv_desc *tlv = (struct tlv_desc *)skb_tail_pointer(skb); |
| 79 | |
| 80 | if (tipc_skb_tailroom(skb) < TLV_SPACE(len)) |
| 81 | return -EMSGSIZE; |
| 82 | |
| 83 | skb_put(skb, TLV_SPACE(len)); |
| 84 | tlv->tlv_type = htons(type); |
| 85 | tlv->tlv_len = htons(TLV_LENGTH(len)); |
| 86 | if (len && data) |
| 87 | memcpy(TLV_DATA(tlv), data, len); |
| 88 | |
| 89 | return 0; |
| 90 | } |
| 91 | |
| 92 | static struct sk_buff *tipc_tlv_alloc(int size) |
| 93 | { |
| 94 | int hdr_len; |
| 95 | struct sk_buff *buf; |
| 96 | |
| 97 | size = TLV_SPACE(size); |
| 98 | hdr_len = nlmsg_total_size(GENL_HDRLEN + TIPC_GENL_HDRLEN); |
| 99 | |
| 100 | buf = alloc_skb(hdr_len + size, GFP_KERNEL); |
| 101 | if (!buf) |
| 102 | return NULL; |
| 103 | |
| 104 | skb_reserve(buf, hdr_len); |
| 105 | |
| 106 | return buf; |
| 107 | } |
| 108 | |
| 109 | static struct sk_buff *tipc_get_err_tlv(char *str) |
| 110 | { |
| 111 | int str_len = strlen(str) + 1; |
| 112 | struct sk_buff *buf; |
| 113 | |
| 114 | buf = tipc_tlv_alloc(TLV_SPACE(str_len)); |
| 115 | if (buf) |
| 116 | tipc_add_tlv(buf, TIPC_TLV_ERROR_STRING, str, str_len); |
| 117 | |
| 118 | return buf; |
| 119 | } |
| 120 | |
| 121 | static int __tipc_nl_compat_dumpit(struct tipc_nl_compat_cmd_dump *cmd, |
| 122 | struct tipc_nl_compat_msg *msg, |
| 123 | struct sk_buff *arg) |
| 124 | { |
| 125 | int len = 0; |
| 126 | int err; |
| 127 | struct sk_buff *buf; |
| 128 | struct nlmsghdr *nlmsg; |
| 129 | struct netlink_callback cb; |
| 130 | |
| 131 | memset(&cb, 0, sizeof(cb)); |
| 132 | cb.nlh = (struct nlmsghdr *)arg->data; |
| 133 | cb.skb = arg; |
| 134 | |
| 135 | buf = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL); |
| 136 | if (!buf) |
| 137 | return -ENOMEM; |
| 138 | |
| 139 | buf->sk = msg->dst_sk; |
| 140 | |
| 141 | do { |
| 142 | int rem; |
| 143 | |
| 144 | len = (*cmd->dumpit)(buf, &cb); |
| 145 | |
| 146 | nlmsg_for_each_msg(nlmsg, nlmsg_hdr(buf), len, rem) { |
| 147 | struct nlattr **attrs; |
| 148 | |
| 149 | err = tipc_nlmsg_parse(nlmsg, &attrs); |
| 150 | if (err) |
| 151 | goto err_out; |
| 152 | |
| 153 | err = (*cmd->format)(msg, attrs); |
| 154 | if (err) |
| 155 | goto err_out; |
| 156 | |
| 157 | if (tipc_skb_tailroom(msg->rep) <= 1) { |
| 158 | err = -EMSGSIZE; |
| 159 | goto err_out; |
| 160 | } |
| 161 | } |
| 162 | |
| 163 | skb_reset_tail_pointer(buf); |
| 164 | buf->len = 0; |
| 165 | |
| 166 | } while (len); |
| 167 | |
| 168 | err = 0; |
| 169 | |
| 170 | err_out: |
| 171 | kfree_skb(buf); |
| 172 | |
| 173 | if (err == -EMSGSIZE) { |
| 174 | /* The legacy API only considered messages filling |
| 175 | * "ULTRA_STRING_MAX_LEN" to be truncated. |
| 176 | */ |
| 177 | if ((TIPC_SKB_MAX - msg->rep->len) <= 1) { |
| 178 | char *tail = skb_tail_pointer(msg->rep); |
| 179 | |
| 180 | if (*tail != '\0') |
| 181 | sprintf(tail - sizeof(REPLY_TRUNCATED) - 1, |
| 182 | REPLY_TRUNCATED); |
| 183 | } |
| 184 | |
| 185 | return 0; |
| 186 | } |
| 187 | |
| 188 | return err; |
| 189 | } |
| 190 | |
| 191 | static int tipc_nl_compat_dumpit(struct tipc_nl_compat_cmd_dump *cmd, |
| 192 | struct tipc_nl_compat_msg *msg) |
| 193 | { |
| 194 | int err; |
| 195 | struct sk_buff *arg; |
| 196 | |
| 197 | msg->rep = tipc_tlv_alloc(msg->rep_size); |
| 198 | if (!msg->rep) |
| 199 | return -ENOMEM; |
| 200 | |
| 201 | arg = nlmsg_new(0, GFP_KERNEL); |
| 202 | if (!arg) { |
| 203 | kfree_skb(msg->rep); |
| 204 | return -ENOMEM; |
| 205 | } |
| 206 | |
| 207 | err = __tipc_nl_compat_dumpit(cmd, msg, arg); |
| 208 | if (err) |
| 209 | kfree_skb(msg->rep); |
| 210 | |
| 211 | kfree_skb(arg); |
| 212 | |
| 213 | return err; |
| 214 | } |
| 215 | |
| 216 | static int tipc_nl_compat_bearer_dump(struct tipc_nl_compat_msg *msg, |
| 217 | struct nlattr **attrs) |
| 218 | { |
| 219 | struct nlattr *bearer[TIPC_NLA_BEARER_MAX + 1]; |
| 220 | |
| 221 | nla_parse_nested(bearer, TIPC_NLA_BEARER_MAX, attrs[TIPC_NLA_BEARER], |
| 222 | NULL); |
| 223 | |
| 224 | return tipc_add_tlv(msg->rep, TIPC_TLV_BEARER_NAME, |
| 225 | nla_data(bearer[TIPC_NLA_BEARER_NAME]), |
| 226 | nla_len(bearer[TIPC_NLA_BEARER_NAME])); |
| 227 | } |
| 228 | |
| 229 | static int tipc_nl_compat_handle(struct tipc_nl_compat_msg *msg) |
| 230 | { |
| 231 | struct tipc_nl_compat_cmd_dump dump; |
| 232 | |
| 233 | memset(&dump, 0, sizeof(dump)); |
| 234 | |
| 235 | switch (msg->cmd) { |
| 236 | case TIPC_CMD_GET_BEARER_NAMES: |
| 237 | msg->rep_size = MAX_BEARERS * TLV_SPACE(TIPC_MAX_BEARER_NAME); |
| 238 | dump.dumpit = tipc_nl_bearer_dump; |
| 239 | dump.format = tipc_nl_compat_bearer_dump; |
| 240 | return tipc_nl_compat_dumpit(&dump, msg); |
| 241 | } |
| 242 | |
| 243 | return -EOPNOTSUPP; |
| 244 | } |
| 245 | |
| 246 | static int tipc_nl_compat_recv(struct sk_buff *skb, struct genl_info *info) |
| 247 | { |
| 248 | int err; |
| 249 | int len; |
| 250 | struct tipc_nl_compat_msg msg; |
| 251 | struct nlmsghdr *req_nlh; |
| 252 | struct nlmsghdr *rep_nlh; |
| 253 | struct tipc_genlmsghdr *req_userhdr = info->userhdr; |
| 254 | struct net *net = genl_info_net(info); |
| 255 | |
| 256 | memset(&msg, 0, sizeof(msg)); |
| 257 | |
| 258 | req_nlh = (struct nlmsghdr *)skb->data; |
| 259 | msg.req = nlmsg_data(req_nlh) + GENL_HDRLEN + TIPC_GENL_HDRLEN; |
| 260 | msg.cmd = req_userhdr->cmd; |
| 261 | msg.dst_sk = info->dst_sk; |
| 262 | |
| 263 | if ((msg.cmd & 0xC000) && (!netlink_net_capable(skb, CAP_NET_ADMIN))) { |
| 264 | msg.rep = tipc_get_err_tlv(TIPC_CFG_NOT_NET_ADMIN); |
| 265 | err = -EACCES; |
| 266 | goto send; |
| 267 | } |
| 268 | |
| 269 | len = nlmsg_attrlen(req_nlh, GENL_HDRLEN + TIPC_GENL_HDRLEN); |
| 270 | if (TLV_GET_LEN(msg.req) && !TLV_OK(msg.req, len)) { |
| 271 | msg.rep = tipc_get_err_tlv(TIPC_CFG_NOT_SUPPORTED); |
| 272 | err = -EOPNOTSUPP; |
| 273 | goto send; |
| 274 | } |
| 275 | |
| 276 | err = tipc_nl_compat_handle(&msg); |
| 277 | if (err == -EOPNOTSUPP) |
| 278 | msg.rep = tipc_get_err_tlv(TIPC_CFG_NOT_SUPPORTED); |
| 279 | else if (err == -EINVAL) |
| 280 | msg.rep = tipc_get_err_tlv(TIPC_CFG_TLV_ERROR); |
| 281 | send: |
| 282 | if (!msg.rep) |
| 283 | return err; |
| 284 | |
| 285 | len = nlmsg_total_size(GENL_HDRLEN + TIPC_GENL_HDRLEN); |
| 286 | skb_push(msg.rep, len); |
| 287 | rep_nlh = nlmsg_hdr(msg.rep); |
| 288 | memcpy(rep_nlh, info->nlhdr, len); |
| 289 | rep_nlh->nlmsg_len = msg.rep->len; |
| 290 | genlmsg_unicast(net, msg.rep, NETLINK_CB(skb).portid); |
| 291 | |
| 292 | return err; |
| 293 | } |
| 294 | |
Richard Alpe | bfb3e5d | 2015-02-09 09:50:03 +0100 | [diff] [blame] | 295 | static int handle_cmd(struct sk_buff *skb, struct genl_info *info) |
| 296 | { |
| 297 | struct net *net = genl_info_net(info); |
| 298 | struct sk_buff *rep_buf; |
| 299 | struct nlmsghdr *rep_nlh; |
| 300 | struct nlmsghdr *req_nlh = info->nlhdr; |
| 301 | struct tipc_genlmsghdr *req_userhdr = info->userhdr; |
| 302 | int hdr_space = nlmsg_total_size(GENL_HDRLEN + TIPC_GENL_HDRLEN); |
| 303 | u16 cmd; |
| 304 | |
| 305 | if ((req_userhdr->cmd & 0xC000) && |
| 306 | (!netlink_net_capable(skb, CAP_NET_ADMIN))) |
| 307 | cmd = TIPC_CMD_NOT_NET_ADMIN; |
| 308 | else |
| 309 | cmd = req_userhdr->cmd; |
| 310 | |
| 311 | rep_buf = tipc_cfg_do_cmd(net, req_userhdr->dest, cmd, |
| 312 | nlmsg_data(req_nlh) + GENL_HDRLEN + |
| 313 | TIPC_GENL_HDRLEN, |
| 314 | nlmsg_attrlen(req_nlh, GENL_HDRLEN + |
| 315 | TIPC_GENL_HDRLEN), hdr_space); |
| 316 | |
| 317 | if (rep_buf) { |
| 318 | skb_push(rep_buf, hdr_space); |
| 319 | rep_nlh = nlmsg_hdr(rep_buf); |
| 320 | memcpy(rep_nlh, req_nlh, hdr_space); |
| 321 | rep_nlh->nlmsg_len = rep_buf->len; |
| 322 | genlmsg_unicast(net, rep_buf, NETLINK_CB(skb).portid); |
| 323 | } |
| 324 | |
| 325 | return 0; |
| 326 | } |
| 327 | |
Richard Alpe | d0796d1 | 2015-02-09 09:50:04 +0100 | [diff] [blame^] | 328 | /* Temporary function to keep functionality throughout the patchset |
| 329 | * without having to mess with the global variables and other trickery |
| 330 | * of the old API. |
| 331 | */ |
| 332 | static int tipc_nl_compat_tmp_wrap(struct sk_buff *skb, struct genl_info *info) |
| 333 | { |
| 334 | struct tipc_genlmsghdr *req = info->userhdr; |
| 335 | |
| 336 | switch (req->cmd) { |
| 337 | case TIPC_CMD_GET_BEARER_NAMES: |
| 338 | return tipc_nl_compat_recv(skb, info); |
| 339 | } |
| 340 | |
| 341 | return handle_cmd(skb, info); |
| 342 | } |
| 343 | |
Richard Alpe | bfb3e5d | 2015-02-09 09:50:03 +0100 | [diff] [blame] | 344 | static struct genl_family tipc_genl_compat_family = { |
| 345 | .id = GENL_ID_GENERATE, |
| 346 | .name = TIPC_GENL_NAME, |
| 347 | .version = TIPC_GENL_VERSION, |
| 348 | .hdrsize = TIPC_GENL_HDRLEN, |
| 349 | .maxattr = 0, |
| 350 | .netnsok = true, |
| 351 | }; |
| 352 | |
| 353 | static struct genl_ops tipc_genl_compat_ops[] = { |
| 354 | { |
| 355 | .cmd = TIPC_GENL_CMD, |
Richard Alpe | d0796d1 | 2015-02-09 09:50:04 +0100 | [diff] [blame^] | 356 | .doit = tipc_nl_compat_tmp_wrap, |
Richard Alpe | bfb3e5d | 2015-02-09 09:50:03 +0100 | [diff] [blame] | 357 | }, |
| 358 | }; |
| 359 | |
| 360 | int tipc_netlink_compat_start(void) |
| 361 | { |
| 362 | int res; |
| 363 | |
| 364 | res = genl_register_family_with_ops(&tipc_genl_compat_family, |
| 365 | tipc_genl_compat_ops); |
| 366 | if (res) { |
| 367 | pr_err("Failed to register legacy compat interface\n"); |
| 368 | return res; |
| 369 | } |
| 370 | |
| 371 | return 0; |
| 372 | } |
| 373 | |
| 374 | void tipc_netlink_compat_stop(void) |
| 375 | { |
| 376 | genl_unregister_family(&tipc_genl_compat_family); |
| 377 | } |