Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 1 | /* |
| 2 | * lib/msg.c Netlink Messages Interface |
| 3 | * |
| 4 | * This library is free software; you can redistribute it and/or |
| 5 | * modify it under the terms of the GNU Lesser General Public |
| 6 | * License as published by the Free Software Foundation version 2.1 |
| 7 | * of the License. |
| 8 | * |
Thomas Graf | 8a3efff | 2008-05-14 17:49:44 +0200 | [diff] [blame] | 9 | * Copyright (c) 2003-2008 Thomas Graf <tgraf@suug.ch> |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 10 | */ |
| 11 | |
| 12 | /** |
Thomas Graf | 6782b6f | 2008-12-10 18:12:30 +0100 | [diff] [blame] | 13 | * @ingroup core |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 14 | * @defgroup msg Messages |
| 15 | * Netlink Message Construction/Parsing Interface |
| 16 | * |
| 17 | * The following information is partly extracted from RFC3549 |
| 18 | * (ftp://ftp.rfc-editor.org/in-notes/rfc3549.txt) |
| 19 | * |
| 20 | * @par Message Format |
| 21 | * Netlink messages consist of a byte stream with one or multiple |
| 22 | * Netlink headers and an associated payload. If the payload is too big |
| 23 | * to fit into a single message it, can be split over multiple Netlink |
| 24 | * messages, collectively called a multipart message. For multipart |
| 25 | * messages, the first and all following headers have the \c NLM_F_MULTI |
| 26 | * Netlink header flag set, except for the last header which has the |
| 27 | * Netlink header type \c NLMSG_DONE. |
| 28 | * |
| 29 | * @par |
| 30 | * The Netlink message header (\link nlmsghdr struct nlmsghdr\endlink) is shown below. |
| 31 | * @code |
| 32 | * 0 1 2 3 |
| 33 | * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 |
| 34 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 35 | * | Length | |
| 36 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 37 | * | Type | Flags | |
| 38 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 39 | * | Sequence Number | |
| 40 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 41 | * | Process ID (PID) | |
| 42 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 43 | * @endcode |
| 44 | * |
| 45 | * @par |
| 46 | * The netlink message header and payload must be aligned properly: |
| 47 | * @code |
| 48 | * <------- NLMSG_ALIGN(hlen) ------> <---- NLMSG_ALIGN(len) ---> |
| 49 | * +----------------------------+- - -+- - - - - - - - - - -+- - -+ |
| 50 | * | Header | Pad | Payload | Pad | |
| 51 | * | struct nlmsghdr | | | | |
| 52 | * +----------------------------+- - -+- - - - - - - - - - -+- - -+ |
| 53 | * @endcode |
| 54 | * @par |
| 55 | * Message Format: |
| 56 | * @code |
| 57 | * <--- nlmsg_total_size(payload) ---> |
| 58 | * <-- nlmsg_msg_size(payload) -> |
| 59 | * +----------+- - -+-------------+- - -+-------- - - |
| 60 | * | nlmsghdr | Pad | Payload | Pad | nlmsghdr |
| 61 | * +----------+- - -+-------------+- - -+-------- - - |
| 62 | * nlmsg_data(nlh)---^ ^ |
| 63 | * nlmsg_next(nlh)-----------------------+ |
| 64 | * @endcode |
| 65 | * @par |
| 66 | * The payload may consist of arbitary data but may have strict |
| 67 | * alignment and formatting rules depening on the specific netlink |
| 68 | * families. |
| 69 | * @par |
| 70 | * @code |
| 71 | * <---------------------- nlmsg_len(nlh) ---------------------> |
| 72 | * <------ hdrlen ------> <- nlmsg_attrlen(nlh, hdrlen) -> |
| 73 | * +----------------------+- - -+--------------------------------+ |
| 74 | * | Family Header | Pad | Attributes | |
| 75 | * +----------------------+- - -+--------------------------------+ |
| 76 | * nlmsg_attrdata(nlh, hdrlen)---^ |
| 77 | * @endcode |
| 78 | * @par The ACK Netlink Message |
| 79 | * This message is actually used to denote both an ACK and a NACK. |
| 80 | * Typically, the direction is from FEC to CPC (in response to an ACK |
| 81 | * request message). However, the CPC should be able to send ACKs back |
| 82 | * to FEC when requested. |
| 83 | * @code |
| 84 | * 0 1 2 3 |
| 85 | * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 |
| 86 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 87 | * | Netlink message header | |
| 88 | * | type = NLMSG_ERROR | |
| 89 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 90 | * | Error code | |
| 91 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 92 | * | OLD Netlink message header | |
| 93 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 94 | * @endcode |
| 95 | * |
Thomas Graf | 75a26f3 | 2008-01-14 16:46:17 +0100 | [diff] [blame] | 96 | * @par Example |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 97 | * @code |
Thomas Graf | 75a26f3 | 2008-01-14 16:46:17 +0100 | [diff] [blame] | 98 | * // Various methods exist to create/allocate a new netlink |
| 99 | * // message. |
| 100 | * // |
| 101 | * // nlmsg_alloc() will allocate an empty netlink message with |
| 102 | * // a maximum payload size which defaults to the page size of |
| 103 | * // the system. This default size can be modified using the |
| 104 | * // function nlmsg_set_default_size(). |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 105 | * struct nl_msg *msg = nlmsg_alloc(); |
| 106 | * |
| 107 | * // Very often, the message type and message flags are known |
| 108 | * // at allocation time while the other fields are auto generated: |
| 109 | * struct nl_msg *msg = nlmsg_alloc_simple(MY_TYPE, MY_FLAGS); |
| 110 | * |
| 111 | * // Alternatively an existing netlink message header can be used |
Thomas Graf | 75a26f3 | 2008-01-14 16:46:17 +0100 | [diff] [blame] | 112 | * // to inherit the header values: |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 113 | * struct nlmsghdr hdr = { |
| 114 | * .nlmsg_type = MY_TYPE, |
| 115 | * .nlmsg_flags = MY_FLAGS, |
| 116 | * }; |
| 117 | * struct nl_msg *msg = nlmsg_inherit(&hdr); |
| 118 | * |
| 119 | * // Last but not least, netlink messages received from netlink sockets |
Thomas Graf | 75a26f3 | 2008-01-14 16:46:17 +0100 | [diff] [blame] | 120 | * // can be converted into nl_msg objects using nlmsg_convert(). This |
| 121 | * // will create a message with a maximum payload size which equals the |
| 122 | * // length of the existing netlink message, therefore no more data can |
| 123 | * // be appened without calling nlmsg_expand() first. |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 124 | * struct nl_msg *msg = nlmsg_convert(nlh_from_nl_sock); |
| 125 | * |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 126 | * // Payload may be added to the message via nlmsg_append(). The fourth |
| 127 | * // parameter specifies the number of alignment bytes the data should |
| 128 | * // be padding with at the end. Common values are 0 to disable it or |
| 129 | * // NLMSG_ALIGNTO to ensure proper netlink message padding. |
| 130 | * nlmsg_append(msg, &mydata, sizeof(mydata), 0); |
| 131 | * |
| 132 | * // Sometimes it may be necessary to reserve room for data but defer |
| 133 | * // the actual copying to a later point, nlmsg_reserve() can be used |
| 134 | * // for this purpose: |
| 135 | * void *data = nlmsg_reserve(msg, sizeof(mydata), NLMSG_ALIGNTO); |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 136 | * |
Thomas Graf | 75a26f3 | 2008-01-14 16:46:17 +0100 | [diff] [blame] | 137 | * // Attributes may be added using the attributes interface. |
| 138 | * |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 139 | * // After successful use of the message, the memory must be freed |
| 140 | * // using nlmsg_free() |
| 141 | * nlmsg_free(msg); |
| 142 | * @endcode |
| 143 | * |
| 144 | * @par 4) Parsing messages |
| 145 | * @code |
| 146 | * int n; |
| 147 | * unsigned char *buf; |
| 148 | * struct nlmsghdr *hdr; |
| 149 | * |
| 150 | * n = nl_recv(handle, NULL, &buf); |
| 151 | * |
| 152 | * hdr = (struct nlmsghdr *) buf; |
| 153 | * while (nlmsg_ok(hdr, n)) { |
| 154 | * // Process message here... |
| 155 | * hdr = nlmsg_next(hdr, &n); |
| 156 | * } |
| 157 | * @endcode |
| 158 | * @{ |
| 159 | */ |
| 160 | |
| 161 | #include <netlink-local.h> |
| 162 | #include <netlink/netlink.h> |
| 163 | #include <netlink/utils.h> |
| 164 | #include <netlink/cache.h> |
| 165 | #include <netlink/attr.h> |
| 166 | #include <linux/socket.h> |
| 167 | |
Thomas Graf | 6de17f3 | 2008-01-14 16:17:56 +0100 | [diff] [blame] | 168 | static size_t default_msg_size; |
| 169 | |
| 170 | static void __init init_msg_size(void) |
| 171 | { |
| 172 | default_msg_size = getpagesize(); |
| 173 | } |
| 174 | |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 175 | /** |
| 176 | * @name Size Calculations |
| 177 | * @{ |
| 178 | */ |
| 179 | |
| 180 | /** |
| 181 | * length of netlink message not including padding |
| 182 | * @arg payload length of message payload |
| 183 | */ |
| 184 | int nlmsg_msg_size(int payload) |
| 185 | { |
| 186 | return NLMSG_HDRLEN + payload; |
| 187 | } |
| 188 | |
| 189 | /** |
| 190 | * length of netlink message including padding |
| 191 | * @arg payload length of message payload |
| 192 | */ |
| 193 | int nlmsg_total_size(int payload) |
| 194 | { |
| 195 | return NLMSG_ALIGN(nlmsg_msg_size(payload)); |
| 196 | } |
| 197 | |
| 198 | /** |
| 199 | * length of padding at the message's tail |
| 200 | * @arg payload length of message payload |
| 201 | */ |
| 202 | int nlmsg_padlen(int payload) |
| 203 | { |
| 204 | return nlmsg_total_size(payload) - nlmsg_msg_size(payload); |
| 205 | } |
| 206 | |
| 207 | /** @} */ |
| 208 | |
| 209 | /** |
| 210 | * @name Payload Access |
| 211 | * @{ |
| 212 | */ |
| 213 | |
| 214 | /** |
| 215 | * head of message payload |
| 216 | * @arg nlh netlink messsage header |
| 217 | */ |
| 218 | void *nlmsg_data(const struct nlmsghdr *nlh) |
| 219 | { |
| 220 | return (unsigned char *) nlh + NLMSG_HDRLEN; |
| 221 | } |
| 222 | |
| 223 | void *nlmsg_tail(const struct nlmsghdr *nlh) |
| 224 | { |
| 225 | return (unsigned char *) nlh + NLMSG_ALIGN(nlh->nlmsg_len); |
| 226 | } |
| 227 | |
| 228 | /** |
| 229 | * length of message payload |
| 230 | * @arg nlh netlink message header |
| 231 | */ |
| 232 | int nlmsg_len(const struct nlmsghdr *nlh) |
| 233 | { |
| 234 | return nlh->nlmsg_len - NLMSG_HDRLEN; |
| 235 | } |
| 236 | |
| 237 | /** @} */ |
| 238 | |
| 239 | /** |
| 240 | * @name Attribute Access |
| 241 | * @{ |
| 242 | */ |
| 243 | |
| 244 | /** |
| 245 | * head of attributes data |
| 246 | * @arg nlh netlink message header |
| 247 | * @arg hdrlen length of family specific header |
| 248 | */ |
| 249 | struct nlattr *nlmsg_attrdata(const struct nlmsghdr *nlh, int hdrlen) |
| 250 | { |
| 251 | unsigned char *data = nlmsg_data(nlh); |
| 252 | return (struct nlattr *) (data + NLMSG_ALIGN(hdrlen)); |
| 253 | } |
| 254 | |
| 255 | /** |
| 256 | * length of attributes data |
| 257 | * @arg nlh netlink message header |
| 258 | * @arg hdrlen length of family specific header |
| 259 | */ |
| 260 | int nlmsg_attrlen(const struct nlmsghdr *nlh, int hdrlen) |
| 261 | { |
| 262 | return nlmsg_len(nlh) - NLMSG_ALIGN(hdrlen); |
| 263 | } |
| 264 | |
| 265 | /** @} */ |
| 266 | |
| 267 | /** |
| 268 | * @name Message Parsing |
| 269 | * @{ |
| 270 | */ |
| 271 | |
Thomas Graf | c8a0a5c | 2008-01-10 12:35:38 +0100 | [diff] [blame] | 272 | int nlmsg_valid_hdr(const struct nlmsghdr *nlh, int hdrlen) |
| 273 | { |
| 274 | if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen)) |
| 275 | return 0; |
| 276 | |
| 277 | return 1; |
| 278 | } |
| 279 | |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 280 | /** |
| 281 | * check if the netlink message fits into the remaining bytes |
| 282 | * @arg nlh netlink message header |
| 283 | * @arg remaining number of bytes remaining in message stream |
| 284 | */ |
| 285 | int nlmsg_ok(const struct nlmsghdr *nlh, int remaining) |
| 286 | { |
Marc de Kruijf | 1ed227d | 2009-08-26 16:28:01 -0500 | [diff] [blame] | 287 | return (remaining >= (int)sizeof(struct nlmsghdr) && |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 288 | nlh->nlmsg_len >= sizeof(struct nlmsghdr) && |
| 289 | nlh->nlmsg_len <= remaining); |
| 290 | } |
| 291 | |
| 292 | /** |
| 293 | * next netlink message in message stream |
| 294 | * @arg nlh netlink message header |
| 295 | * @arg remaining number of bytes remaining in message stream |
| 296 | * |
| 297 | * @returns the next netlink message in the message stream and |
| 298 | * decrements remaining by the size of the current message. |
| 299 | */ |
| 300 | struct nlmsghdr *nlmsg_next(struct nlmsghdr *nlh, int *remaining) |
| 301 | { |
| 302 | int totlen = NLMSG_ALIGN(nlh->nlmsg_len); |
| 303 | |
| 304 | *remaining -= totlen; |
| 305 | |
| 306 | return (struct nlmsghdr *) ((unsigned char *) nlh + totlen); |
| 307 | } |
| 308 | |
| 309 | /** |
| 310 | * parse attributes of a netlink message |
| 311 | * @arg nlh netlink message header |
| 312 | * @arg hdrlen length of family specific header |
| 313 | * @arg tb destination array with maxtype+1 elements |
| 314 | * @arg maxtype maximum attribute type to be expected |
| 315 | * @arg policy validation policy |
| 316 | * |
| 317 | * See nla_parse() |
| 318 | */ |
| 319 | int nlmsg_parse(struct nlmsghdr *nlh, int hdrlen, struct nlattr *tb[], |
| 320 | int maxtype, struct nla_policy *policy) |
| 321 | { |
Thomas Graf | c8a0a5c | 2008-01-10 12:35:38 +0100 | [diff] [blame] | 322 | if (!nlmsg_valid_hdr(nlh, hdrlen)) |
Thomas Graf | 8a3efff | 2008-05-14 17:49:44 +0200 | [diff] [blame] | 323 | return -NLE_MSG_TOOSHORT; |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 324 | |
| 325 | return nla_parse(tb, maxtype, nlmsg_attrdata(nlh, hdrlen), |
| 326 | nlmsg_attrlen(nlh, hdrlen), policy); |
| 327 | } |
| 328 | |
| 329 | /** |
| 330 | * nlmsg_find_attr - find a specific attribute in a netlink message |
| 331 | * @arg nlh netlink message header |
| 332 | * @arg hdrlen length of familiy specific header |
| 333 | * @arg attrtype type of attribute to look for |
| 334 | * |
| 335 | * Returns the first attribute which matches the specified type. |
| 336 | */ |
| 337 | struct nlattr *nlmsg_find_attr(struct nlmsghdr *nlh, int hdrlen, int attrtype) |
| 338 | { |
| 339 | return nla_find(nlmsg_attrdata(nlh, hdrlen), |
| 340 | nlmsg_attrlen(nlh, hdrlen), attrtype); |
| 341 | } |
| 342 | |
| 343 | /** |
| 344 | * nlmsg_validate - validate a netlink message including attributes |
| 345 | * @arg nlh netlinket message header |
| 346 | * @arg hdrlen length of familiy specific header |
| 347 | * @arg maxtype maximum attribute type to be expected |
| 348 | * @arg policy validation policy |
| 349 | */ |
| 350 | int nlmsg_validate(struct nlmsghdr *nlh, int hdrlen, int maxtype, |
| 351 | struct nla_policy *policy) |
| 352 | { |
Thomas Graf | c8a0a5c | 2008-01-10 12:35:38 +0100 | [diff] [blame] | 353 | if (!nlmsg_valid_hdr(nlh, hdrlen)) |
Thomas Graf | 8a3efff | 2008-05-14 17:49:44 +0200 | [diff] [blame] | 354 | return -NLE_MSG_TOOSHORT; |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 355 | |
| 356 | return nla_validate(nlmsg_attrdata(nlh, hdrlen), |
| 357 | nlmsg_attrlen(nlh, hdrlen), maxtype, policy); |
| 358 | } |
| 359 | |
| 360 | /** @} */ |
| 361 | |
| 362 | /** |
| 363 | * @name Message Building/Access |
| 364 | * @{ |
| 365 | */ |
| 366 | |
| 367 | static struct nl_msg *__nlmsg_alloc(size_t len) |
| 368 | { |
| 369 | struct nl_msg *nm; |
| 370 | |
| 371 | nm = calloc(1, sizeof(*nm)); |
| 372 | if (!nm) |
| 373 | goto errout; |
| 374 | |
Thomas Graf | 23ee46e | 2008-10-14 19:26:44 +0200 | [diff] [blame] | 375 | nm->nm_refcnt = 1; |
| 376 | |
Thomas Graf | b7c5bf9 | 2008-05-07 13:18:30 +0200 | [diff] [blame] | 377 | nm->nm_nlh = malloc(len); |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 378 | if (!nm->nm_nlh) |
| 379 | goto errout; |
| 380 | |
Thomas Graf | b7c5bf9 | 2008-05-07 13:18:30 +0200 | [diff] [blame] | 381 | memset(nm->nm_nlh, 0, sizeof(struct nlmsghdr)); |
| 382 | |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 383 | nm->nm_protocol = -1; |
Thomas Graf | 6de17f3 | 2008-01-14 16:17:56 +0100 | [diff] [blame] | 384 | nm->nm_size = len; |
| 385 | nm->nm_nlh->nlmsg_len = nlmsg_total_size(0); |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 386 | |
Thomas Graf | 6de17f3 | 2008-01-14 16:17:56 +0100 | [diff] [blame] | 387 | NL_DBG(2, "msg %p: Allocated new message, maxlen=%zu\n", nm, len); |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 388 | |
| 389 | return nm; |
| 390 | errout: |
| 391 | free(nm); |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 392 | return NULL; |
| 393 | } |
| 394 | |
| 395 | /** |
Thomas Graf | 6de17f3 | 2008-01-14 16:17:56 +0100 | [diff] [blame] | 396 | * Allocate a new netlink message with the default maximum payload size. |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 397 | * |
Thomas Graf | 6de17f3 | 2008-01-14 16:17:56 +0100 | [diff] [blame] | 398 | * Allocates a new netlink message without any further payload. The |
| 399 | * maximum payload size defaults to PAGESIZE or as otherwise specified |
| 400 | * with nlmsg_set_default_size(). |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 401 | * |
| 402 | * @return Newly allocated netlink message or NULL. |
| 403 | */ |
| 404 | struct nl_msg *nlmsg_alloc(void) |
| 405 | { |
Thomas Graf | 6de17f3 | 2008-01-14 16:17:56 +0100 | [diff] [blame] | 406 | return __nlmsg_alloc(default_msg_size); |
| 407 | } |
| 408 | |
| 409 | /** |
| 410 | * Allocate a new netlink message with maximum payload size specified. |
| 411 | */ |
| 412 | struct nl_msg *nlmsg_alloc_size(size_t max) |
| 413 | { |
| 414 | return __nlmsg_alloc(max); |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 415 | } |
| 416 | |
| 417 | /** |
| 418 | * Allocate a new netlink message and inherit netlink message header |
| 419 | * @arg hdr Netlink message header template |
| 420 | * |
Thomas Graf | 6de17f3 | 2008-01-14 16:17:56 +0100 | [diff] [blame] | 421 | * Allocates a new netlink message and inherits the original message |
| 422 | * header. If \a hdr is not NULL it will be used as a template for |
| 423 | * the netlink message header, otherwise the header is left blank. |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 424 | * |
| 425 | * @return Newly allocated netlink message or NULL |
| 426 | */ |
| 427 | struct nl_msg *nlmsg_inherit(struct nlmsghdr *hdr) |
| 428 | { |
| 429 | struct nl_msg *nm; |
| 430 | |
| 431 | nm = nlmsg_alloc(); |
| 432 | if (nm && hdr) { |
| 433 | struct nlmsghdr *new = nm->nm_nlh; |
| 434 | |
| 435 | new->nlmsg_type = hdr->nlmsg_type; |
| 436 | new->nlmsg_flags = hdr->nlmsg_flags; |
| 437 | new->nlmsg_seq = hdr->nlmsg_seq; |
| 438 | new->nlmsg_pid = hdr->nlmsg_pid; |
| 439 | } |
| 440 | |
| 441 | return nm; |
| 442 | } |
| 443 | |
| 444 | /** |
| 445 | * Allocate a new netlink message |
| 446 | * @arg nlmsgtype Netlink message type |
| 447 | * @arg flags Message flags. |
| 448 | * |
| 449 | * @return Newly allocated netlink message or NULL. |
| 450 | */ |
| 451 | struct nl_msg *nlmsg_alloc_simple(int nlmsgtype, int flags) |
| 452 | { |
| 453 | struct nl_msg *msg; |
| 454 | struct nlmsghdr nlh = { |
| 455 | .nlmsg_type = nlmsgtype, |
| 456 | .nlmsg_flags = flags, |
| 457 | }; |
| 458 | |
| 459 | msg = nlmsg_inherit(&nlh); |
| 460 | if (msg) |
| 461 | NL_DBG(2, "msg %p: Allocated new simple message\n", msg); |
| 462 | |
| 463 | return msg; |
| 464 | } |
| 465 | |
| 466 | /** |
Thomas Graf | 6de17f3 | 2008-01-14 16:17:56 +0100 | [diff] [blame] | 467 | * Set the default maximum message payload size for allocated messages |
| 468 | * @arg max Size of payload in bytes. |
| 469 | */ |
| 470 | void nlmsg_set_default_size(size_t max) |
| 471 | { |
| 472 | if (max < nlmsg_total_size(0)) |
| 473 | max = nlmsg_total_size(0); |
| 474 | |
| 475 | default_msg_size = max; |
| 476 | } |
| 477 | |
| 478 | /** |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 479 | * Convert a netlink message received from a netlink socket to a nl_msg |
| 480 | * @arg hdr Netlink message received from netlink socket. |
| 481 | * |
| 482 | * Allocates a new netlink message and copies all of the data pointed to |
| 483 | * by \a hdr into the new message object. |
| 484 | * |
| 485 | * @return Newly allocated netlink message or NULL. |
| 486 | */ |
| 487 | struct nl_msg *nlmsg_convert(struct nlmsghdr *hdr) |
| 488 | { |
| 489 | struct nl_msg *nm; |
| 490 | |
| 491 | nm = __nlmsg_alloc(NLMSG_ALIGN(hdr->nlmsg_len)); |
| 492 | if (!nm) |
| 493 | goto errout; |
| 494 | |
| 495 | memcpy(nm->nm_nlh, hdr, hdr->nlmsg_len); |
| 496 | |
| 497 | return nm; |
| 498 | errout: |
| 499 | nlmsg_free(nm); |
| 500 | return NULL; |
| 501 | } |
| 502 | |
| 503 | /** |
| 504 | * Reserve room for additional data in a netlink message |
| 505 | * @arg n netlink message |
| 506 | * @arg len length of additional data to reserve room for |
| 507 | * @arg pad number of bytes to align data to |
| 508 | * |
| 509 | * Reserves room for additional data at the tail of the an |
| 510 | * existing netlink message. Eventual padding required will |
| 511 | * be zeroed out. |
| 512 | * |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 513 | * @return Pointer to start of additional data tailroom or NULL. |
| 514 | */ |
| 515 | void *nlmsg_reserve(struct nl_msg *n, size_t len, int pad) |
| 516 | { |
Thomas Graf | 6de17f3 | 2008-01-14 16:17:56 +0100 | [diff] [blame] | 517 | void *buf = n->nm_nlh; |
| 518 | size_t nlmsg_len = n->nm_nlh->nlmsg_len; |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 519 | size_t tlen; |
| 520 | |
Paul Stewart | 07276b6 | 2017-02-02 12:02:47 -0800 | [diff] [blame] | 521 | if (len > n->nm_size) |
| 522 | return NULL; |
| 523 | |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 524 | tlen = pad ? ((len + (pad - 1)) & ~(pad - 1)) : len; |
| 525 | |
Thomas Graf | 8a3efff | 2008-05-14 17:49:44 +0200 | [diff] [blame] | 526 | if ((tlen + nlmsg_len) > n->nm_size) |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 527 | return NULL; |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 528 | |
Thomas Graf | 6de17f3 | 2008-01-14 16:17:56 +0100 | [diff] [blame] | 529 | buf += nlmsg_len; |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 530 | n->nm_nlh->nlmsg_len += tlen; |
| 531 | |
| 532 | if (tlen > len) |
Thomas Graf | 6de17f3 | 2008-01-14 16:17:56 +0100 | [diff] [blame] | 533 | memset(buf + len, 0, tlen - len); |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 534 | |
Patrick McHardy | 936c984 | 2007-12-13 12:09:45 +0100 | [diff] [blame] | 535 | NL_DBG(2, "msg %p: Reserved %zu bytes, pad=%d, nlmsg_len=%d\n", |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 536 | n, len, pad, n->nm_nlh->nlmsg_len); |
| 537 | |
Thomas Graf | 6de17f3 | 2008-01-14 16:17:56 +0100 | [diff] [blame] | 538 | return buf; |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 539 | } |
| 540 | |
| 541 | /** |
| 542 | * Append data to tail of a netlink message |
| 543 | * @arg n netlink message |
| 544 | * @arg data data to add |
| 545 | * @arg len length of data |
| 546 | * @arg pad Number of bytes to align data to. |
| 547 | * |
| 548 | * Extends the netlink message as needed and appends the data of given |
| 549 | * length to the message. |
| 550 | * |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 551 | * @return 0 on success or a negative error code |
| 552 | */ |
| 553 | int nlmsg_append(struct nl_msg *n, void *data, size_t len, int pad) |
| 554 | { |
| 555 | void *tmp; |
| 556 | |
| 557 | tmp = nlmsg_reserve(n, len, pad); |
| 558 | if (tmp == NULL) |
Thomas Graf | 8a3efff | 2008-05-14 17:49:44 +0200 | [diff] [blame] | 559 | return -NLE_NOMEM; |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 560 | |
| 561 | memcpy(tmp, data, len); |
Patrick McHardy | 936c984 | 2007-12-13 12:09:45 +0100 | [diff] [blame] | 562 | NL_DBG(2, "msg %p: Appended %zu bytes with padding %d\n", n, len, pad); |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 563 | |
| 564 | return 0; |
| 565 | } |
| 566 | |
| 567 | /** |
Thomas Graf | 75a26f3 | 2008-01-14 16:46:17 +0100 | [diff] [blame] | 568 | * Expand maximum payload size of a netlink message |
| 569 | * @arg n Netlink message. |
| 570 | * @arg newlen New maximum payload size. |
| 571 | * |
| 572 | * Reallocates the payload section of a netlink message and increases |
| 573 | * the maximum payload size of the message. |
| 574 | * |
| 575 | * @note Any pointers pointing to old payload block will be stale and |
| 576 | * need to be refetched. Therfore, do not expand while constructing |
| 577 | * nested attributes or while reserved data blocks are held. |
| 578 | * |
| 579 | * @return 0 on success or a negative error code. |
| 580 | */ |
| 581 | int nlmsg_expand(struct nl_msg *n, size_t newlen) |
| 582 | { |
| 583 | void *tmp; |
| 584 | |
| 585 | if (newlen <= n->nm_size) |
Thomas Graf | 8a3efff | 2008-05-14 17:49:44 +0200 | [diff] [blame] | 586 | return -NLE_INVAL; |
Thomas Graf | 75a26f3 | 2008-01-14 16:46:17 +0100 | [diff] [blame] | 587 | |
| 588 | tmp = realloc(n->nm_nlh, newlen); |
| 589 | if (tmp == NULL) |
Thomas Graf | 8a3efff | 2008-05-14 17:49:44 +0200 | [diff] [blame] | 590 | return -NLE_NOMEM; |
Thomas Graf | 75a26f3 | 2008-01-14 16:46:17 +0100 | [diff] [blame] | 591 | |
| 592 | n->nm_nlh = tmp; |
| 593 | n->nm_size = newlen; |
| 594 | |
| 595 | return 0; |
| 596 | } |
| 597 | |
| 598 | /** |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 599 | * Add a netlink message header to a netlink message |
| 600 | * @arg n netlink message |
| 601 | * @arg pid netlink process id or NL_AUTO_PID |
| 602 | * @arg seq sequence number of message or NL_AUTO_SEQ |
| 603 | * @arg type message type |
| 604 | * @arg payload length of message payload |
| 605 | * @arg flags message flags |
| 606 | * |
| 607 | * Adds or overwrites the netlink message header in an existing message |
| 608 | * object. If \a payload is greater-than zero additional room will be |
| 609 | * reserved, f.e. for family specific headers. It can be accesed via |
| 610 | * nlmsg_data(). |
| 611 | * |
| 612 | * @return A pointer to the netlink message header or NULL. |
| 613 | */ |
| 614 | struct nlmsghdr *nlmsg_put(struct nl_msg *n, uint32_t pid, uint32_t seq, |
| 615 | int type, int payload, int flags) |
| 616 | { |
| 617 | struct nlmsghdr *nlh; |
| 618 | |
| 619 | if (n->nm_nlh->nlmsg_len < NLMSG_HDRLEN) |
| 620 | BUG(); |
| 621 | |
| 622 | nlh = (struct nlmsghdr *) n->nm_nlh; |
| 623 | nlh->nlmsg_type = type; |
| 624 | nlh->nlmsg_flags = flags; |
| 625 | nlh->nlmsg_pid = pid; |
| 626 | nlh->nlmsg_seq = seq; |
| 627 | |
| 628 | NL_DBG(2, "msg %p: Added netlink header type=%d, flags=%d, pid=%d, " |
| 629 | "seq=%d\n", n, type, flags, pid, seq); |
| 630 | |
| 631 | if (payload > 0 && |
| 632 | nlmsg_reserve(n, payload, NLMSG_ALIGNTO) == NULL) |
| 633 | return NULL; |
| 634 | |
| 635 | return nlh; |
| 636 | } |
| 637 | |
| 638 | /** |
| 639 | * Return actual netlink message |
| 640 | * @arg n netlink message |
| 641 | * |
| 642 | * Returns the actual netlink message casted to the type of the netlink |
| 643 | * message header. |
| 644 | * |
| 645 | * @return A pointer to the netlink message. |
| 646 | */ |
| 647 | struct nlmsghdr *nlmsg_hdr(struct nl_msg *n) |
| 648 | { |
| 649 | return n->nm_nlh; |
| 650 | } |
| 651 | |
| 652 | /** |
Thomas Graf | 23ee46e | 2008-10-14 19:26:44 +0200 | [diff] [blame] | 653 | * Acquire a reference on a netlink message |
| 654 | * @arg msg message to acquire reference from |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 655 | */ |
Thomas Graf | 23ee46e | 2008-10-14 19:26:44 +0200 | [diff] [blame] | 656 | void nlmsg_get(struct nl_msg *msg) |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 657 | { |
Thomas Graf | 23ee46e | 2008-10-14 19:26:44 +0200 | [diff] [blame] | 658 | msg->nm_refcnt++; |
| 659 | NL_DBG(4, "New reference to message %p, total %d\n", |
| 660 | msg, msg->nm_refcnt); |
| 661 | } |
| 662 | |
| 663 | /** |
| 664 | * Release a reference from an netlink message |
| 665 | * @arg msg message to release reference from |
| 666 | * |
| 667 | * Frees memory after the last reference has been released. |
| 668 | */ |
| 669 | void nlmsg_free(struct nl_msg *msg) |
| 670 | { |
| 671 | if (!msg) |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 672 | return; |
| 673 | |
Thomas Graf | 23ee46e | 2008-10-14 19:26:44 +0200 | [diff] [blame] | 674 | msg->nm_refcnt--; |
| 675 | NL_DBG(4, "Returned message reference %p, %d remaining\n", |
| 676 | msg, msg->nm_refcnt); |
| 677 | |
| 678 | if (msg->nm_refcnt < 0) |
| 679 | BUG(); |
| 680 | |
| 681 | if (msg->nm_refcnt <= 0) { |
| 682 | free(msg->nm_nlh); |
| 683 | free(msg); |
| 684 | NL_DBG(2, "msg %p: Freed\n", msg); |
| 685 | } |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 686 | } |
| 687 | |
| 688 | /** @} */ |
| 689 | |
| 690 | /** |
| 691 | * @name Attributes |
| 692 | * @{ |
| 693 | */ |
| 694 | |
| 695 | void nlmsg_set_proto(struct nl_msg *msg, int protocol) |
| 696 | { |
| 697 | msg->nm_protocol = protocol; |
| 698 | } |
| 699 | |
| 700 | int nlmsg_get_proto(struct nl_msg *msg) |
| 701 | { |
| 702 | return msg->nm_protocol; |
| 703 | } |
| 704 | |
Thomas Graf | 75a26f3 | 2008-01-14 16:46:17 +0100 | [diff] [blame] | 705 | size_t nlmsg_get_max_size(struct nl_msg *msg) |
| 706 | { |
| 707 | return msg->nm_size; |
| 708 | } |
| 709 | |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 710 | void nlmsg_set_src(struct nl_msg *msg, struct sockaddr_nl *addr) |
| 711 | { |
| 712 | memcpy(&msg->nm_src, addr, sizeof(*addr)); |
| 713 | } |
| 714 | |
| 715 | struct sockaddr_nl *nlmsg_get_src(struct nl_msg *msg) |
| 716 | { |
| 717 | return &msg->nm_src; |
| 718 | } |
| 719 | |
| 720 | void nlmsg_set_dst(struct nl_msg *msg, struct sockaddr_nl *addr) |
| 721 | { |
| 722 | memcpy(&msg->nm_dst, addr, sizeof(*addr)); |
| 723 | } |
| 724 | |
| 725 | struct sockaddr_nl *nlmsg_get_dst(struct nl_msg *msg) |
| 726 | { |
| 727 | return &msg->nm_dst; |
| 728 | } |
| 729 | |
| 730 | void nlmsg_set_creds(struct nl_msg *msg, struct ucred *creds) |
| 731 | { |
| 732 | memcpy(&msg->nm_creds, creds, sizeof(*creds)); |
| 733 | msg->nm_flags |= NL_MSG_CRED_PRESENT; |
| 734 | } |
| 735 | |
| 736 | struct ucred *nlmsg_get_creds(struct nl_msg *msg) |
| 737 | { |
| 738 | if (msg->nm_flags & NL_MSG_CRED_PRESENT) |
| 739 | return &msg->nm_creds; |
| 740 | return NULL; |
| 741 | } |
| 742 | |
| 743 | /** @} */ |
| 744 | |
| 745 | /** |
| 746 | * @name Netlink Message Type Translations |
| 747 | * @{ |
| 748 | */ |
| 749 | |
| 750 | static struct trans_tbl nl_msgtypes[] = { |
| 751 | __ADD(NLMSG_NOOP,NOOP) |
| 752 | __ADD(NLMSG_ERROR,ERROR) |
| 753 | __ADD(NLMSG_DONE,DONE) |
| 754 | __ADD(NLMSG_OVERRUN,OVERRUN) |
| 755 | }; |
| 756 | |
| 757 | char *nl_nlmsgtype2str(int type, char *buf, size_t size) |
| 758 | { |
| 759 | return __type2str(type, buf, size, nl_msgtypes, |
| 760 | ARRAY_SIZE(nl_msgtypes)); |
| 761 | } |
| 762 | |
| 763 | int nl_str2nlmsgtype(const char *name) |
| 764 | { |
| 765 | return __str2type(name, nl_msgtypes, ARRAY_SIZE(nl_msgtypes)); |
| 766 | } |
| 767 | |
| 768 | /** @} */ |
| 769 | |
| 770 | /** |
| 771 | * @name Netlink Message Flags Translations |
| 772 | * @{ |
| 773 | */ |
| 774 | |
| 775 | char *nl_nlmsg_flags2str(int flags, char *buf, size_t len) |
| 776 | { |
| 777 | memset(buf, 0, len); |
| 778 | |
| 779 | #define PRINT_FLAG(f) \ |
| 780 | if (flags & NLM_F_##f) { \ |
| 781 | flags &= ~NLM_F_##f; \ |
| 782 | strncat(buf, #f, len - strlen(buf) - 1); \ |
| 783 | if (flags) \ |
| 784 | strncat(buf, ",", len - strlen(buf) - 1); \ |
| 785 | } |
| 786 | |
| 787 | PRINT_FLAG(REQUEST); |
| 788 | PRINT_FLAG(MULTI); |
| 789 | PRINT_FLAG(ACK); |
| 790 | PRINT_FLAG(ECHO); |
| 791 | PRINT_FLAG(ROOT); |
| 792 | PRINT_FLAG(MATCH); |
| 793 | PRINT_FLAG(ATOMIC); |
| 794 | PRINT_FLAG(REPLACE); |
| 795 | PRINT_FLAG(EXCL); |
| 796 | PRINT_FLAG(CREATE); |
| 797 | PRINT_FLAG(APPEND); |
| 798 | |
| 799 | if (flags) { |
| 800 | char s[32]; |
| 801 | snprintf(s, sizeof(s), "0x%x", flags); |
| 802 | strncat(buf, s, len - strlen(buf) - 1); |
| 803 | } |
| 804 | #undef PRINT_FLAG |
| 805 | |
| 806 | return buf; |
| 807 | } |
| 808 | |
| 809 | /** @} */ |
| 810 | |
| 811 | /** |
| 812 | * @name Direct Parsing |
| 813 | * @{ |
| 814 | */ |
| 815 | |
| 816 | /** @cond SKIP */ |
| 817 | struct dp_xdata { |
| 818 | void (*cb)(struct nl_object *, void *); |
| 819 | void *arg; |
| 820 | }; |
| 821 | /** @endcond */ |
| 822 | |
| 823 | static int parse_cb(struct nl_object *obj, struct nl_parser_param *p) |
| 824 | { |
| 825 | struct dp_xdata *x = p->pp_arg; |
| 826 | |
| 827 | x->cb(obj, x->arg); |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 828 | return 0; |
| 829 | } |
| 830 | |
| 831 | int nl_msg_parse(struct nl_msg *msg, void (*cb)(struct nl_object *, void *), |
| 832 | void *arg) |
| 833 | { |
| 834 | struct nl_cache_ops *ops; |
| 835 | struct nl_parser_param p = { |
| 836 | .pp_cb = parse_cb |
| 837 | }; |
| 838 | struct dp_xdata x = { |
| 839 | .cb = cb, |
| 840 | .arg = arg, |
| 841 | }; |
| 842 | |
Thomas Graf | d36d396 | 2007-10-11 23:09:49 +0200 | [diff] [blame] | 843 | ops = nl_cache_ops_associate(nlmsg_get_proto(msg), |
| 844 | nlmsg_hdr(msg)->nlmsg_type); |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 845 | if (ops == NULL) |
Thomas Graf | 8a3efff | 2008-05-14 17:49:44 +0200 | [diff] [blame] | 846 | return -NLE_MSGTYPE_NOSUPPORT; |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 847 | p.pp_arg = &x; |
| 848 | |
| 849 | return nl_cache_parse(ops, NULL, nlmsg_hdr(msg), &p); |
| 850 | } |
| 851 | |
| 852 | /** @} */ |
| 853 | |
| 854 | /** |
| 855 | * @name Dumping |
| 856 | * @{ |
| 857 | */ |
| 858 | |
| 859 | static void prefix_line(FILE *ofd, int prefix) |
| 860 | { |
| 861 | int i; |
| 862 | |
| 863 | for (i = 0; i < prefix; i++) |
| 864 | fprintf(ofd, " "); |
| 865 | } |
| 866 | |
| 867 | static inline void dump_hex(FILE *ofd, char *start, int len, int prefix) |
| 868 | { |
| 869 | int i, a, c, limit; |
| 870 | char ascii[21] = {0}; |
| 871 | |
| 872 | limit = 18 - (prefix * 2); |
| 873 | prefix_line(ofd, prefix); |
| 874 | fprintf(ofd, " "); |
| 875 | |
| 876 | for (i = 0, a = 0, c = 0; i < len; i++) { |
| 877 | int v = *(uint8_t *) (start + i); |
| 878 | |
| 879 | fprintf(ofd, "%02x ", v); |
| 880 | ascii[a++] = isprint(v) ? v : '.'; |
| 881 | |
| 882 | if (c == limit-1) { |
| 883 | fprintf(ofd, "%s\n", ascii); |
| 884 | if (i < (len - 1)) { |
| 885 | prefix_line(ofd, prefix); |
| 886 | fprintf(ofd, " "); |
| 887 | } |
| 888 | a = c = 0; |
| 889 | memset(ascii, 0, sizeof(ascii)); |
| 890 | } else |
| 891 | c++; |
| 892 | } |
| 893 | |
| 894 | if (c != 0) { |
| 895 | for (i = 0; i < (limit - c); i++) |
| 896 | fprintf(ofd, " "); |
| 897 | fprintf(ofd, "%s\n", ascii); |
| 898 | } |
| 899 | } |
| 900 | |
| 901 | static void print_hdr(FILE *ofd, struct nl_msg *msg) |
| 902 | { |
| 903 | struct nlmsghdr *nlh = nlmsg_hdr(msg); |
| 904 | struct nl_cache_ops *ops; |
Thomas Graf | d36d396 | 2007-10-11 23:09:49 +0200 | [diff] [blame] | 905 | struct nl_msgtype *mt; |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 906 | char buf[128]; |
| 907 | |
| 908 | fprintf(ofd, " .nlmsg_len = %d\n", nlh->nlmsg_len); |
| 909 | |
Thomas Graf | d36d396 | 2007-10-11 23:09:49 +0200 | [diff] [blame] | 910 | ops = nl_cache_ops_associate(nlmsg_get_proto(msg), nlh->nlmsg_type); |
| 911 | if (ops) { |
| 912 | mt = nl_msgtype_lookup(ops, nlh->nlmsg_type); |
| 913 | if (!mt) |
| 914 | BUG(); |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 915 | |
Thomas Graf | d36d396 | 2007-10-11 23:09:49 +0200 | [diff] [blame] | 916 | snprintf(buf, sizeof(buf), "%s::%s", ops->co_name, mt->mt_name); |
| 917 | } else |
| 918 | nl_nlmsgtype2str(nlh->nlmsg_type, buf, sizeof(buf)); |
| 919 | |
| 920 | fprintf(ofd, " .nlmsg_type = %d <%s>\n", nlh->nlmsg_type, buf); |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 921 | fprintf(ofd, " .nlmsg_flags = %d <%s>\n", nlh->nlmsg_flags, |
| 922 | nl_nlmsg_flags2str(nlh->nlmsg_flags, buf, sizeof(buf))); |
| 923 | fprintf(ofd, " .nlmsg_seq = %d\n", nlh->nlmsg_seq); |
| 924 | fprintf(ofd, " .nlmsg_pid = %d\n", nlh->nlmsg_pid); |
| 925 | |
| 926 | } |
| 927 | |
| 928 | static void dump_attrs(FILE *ofd, struct nlattr *attrs, int attrlen, |
| 929 | int prefix) |
| 930 | { |
| 931 | int rem; |
| 932 | struct nlattr *nla; |
| 933 | |
| 934 | nla_for_each_attr(nla, attrs, attrlen, rem) { |
| 935 | int padlen, alen = nla_len(nla); |
| 936 | |
| 937 | prefix_line(ofd, prefix); |
| 938 | fprintf(ofd, " [ATTR %02d%s] %d octets\n", nla_type(nla), |
| 939 | nla->nla_type & NLA_F_NESTED ? " NESTED" : "", |
| 940 | alen); |
| 941 | |
| 942 | if (nla->nla_type & NLA_F_NESTED) |
| 943 | dump_attrs(ofd, nla_data(nla), alen, prefix+1); |
| 944 | else |
| 945 | dump_hex(ofd, nla_data(nla), alen, prefix); |
| 946 | |
| 947 | padlen = nla_padlen(alen); |
| 948 | if (padlen > 0) { |
| 949 | prefix_line(ofd, prefix); |
| 950 | fprintf(ofd, " [PADDING] %d octets\n", |
| 951 | padlen); |
| 952 | dump_hex(ofd, nla_data(nla) + alen, |
| 953 | padlen, prefix); |
| 954 | } |
| 955 | } |
| 956 | |
| 957 | if (rem) { |
| 958 | prefix_line(ofd, prefix); |
| 959 | fprintf(ofd, " [LEFTOVER] %d octets\n", rem); |
| 960 | } |
| 961 | } |
| 962 | |
| 963 | /** |
| 964 | * Dump message in human readable format to file descriptor |
| 965 | * @arg msg Message to print |
| 966 | * @arg ofd File descriptor. |
| 967 | */ |
| 968 | void nl_msg_dump(struct nl_msg *msg, FILE *ofd) |
| 969 | { |
| 970 | struct nlmsghdr *hdr = nlmsg_hdr(msg); |
| 971 | |
| 972 | fprintf(ofd, |
| 973 | "-------------------------- BEGIN NETLINK MESSAGE " |
| 974 | "---------------------------\n"); |
| 975 | |
| 976 | fprintf(ofd, " [HEADER] %Zu octets\n", sizeof(struct nlmsghdr)); |
| 977 | print_hdr(ofd, msg); |
| 978 | |
| 979 | if (hdr->nlmsg_type == NLMSG_ERROR && |
| 980 | hdr->nlmsg_len >= nlmsg_msg_size(sizeof(struct nlmsgerr))) { |
| 981 | struct nl_msg *errmsg; |
| 982 | struct nlmsgerr *err = nlmsg_data(hdr); |
| 983 | |
| 984 | fprintf(ofd, " [ERRORMSG] %Zu octets\n", sizeof(*err)); |
| 985 | fprintf(ofd, " .error = %d \"%s\"\n", err->error, |
| 986 | strerror(-err->error)); |
| 987 | fprintf(ofd, " [ORIGINAL MESSAGE] %Zu octets\n", sizeof(*hdr)); |
| 988 | |
| 989 | errmsg = nlmsg_inherit(&err->msg); |
| 990 | print_hdr(ofd, errmsg); |
| 991 | nlmsg_free(errmsg); |
| 992 | } else if (nlmsg_len(hdr) > 0) { |
| 993 | struct nl_cache_ops *ops; |
| 994 | int payloadlen = nlmsg_len(hdr); |
| 995 | int attrlen = 0; |
| 996 | |
Thomas Graf | d36d396 | 2007-10-11 23:09:49 +0200 | [diff] [blame] | 997 | ops = nl_cache_ops_associate(nlmsg_get_proto(msg), |
| 998 | hdr->nlmsg_type); |
Thomas Graf | 44d3624 | 2007-09-15 01:28:01 +0200 | [diff] [blame] | 999 | if (ops) { |
| 1000 | attrlen = nlmsg_attrlen(hdr, ops->co_hdrsize); |
| 1001 | payloadlen -= attrlen; |
| 1002 | } |
| 1003 | |
| 1004 | fprintf(ofd, " [PAYLOAD] %d octets\n", payloadlen); |
| 1005 | dump_hex(ofd, nlmsg_data(hdr), payloadlen, 0); |
| 1006 | |
| 1007 | if (attrlen) { |
| 1008 | struct nlattr *attrs; |
| 1009 | int attrlen; |
| 1010 | |
| 1011 | attrs = nlmsg_attrdata(hdr, ops->co_hdrsize); |
| 1012 | attrlen = nlmsg_attrlen(hdr, ops->co_hdrsize); |
| 1013 | dump_attrs(ofd, attrs, attrlen, 0); |
| 1014 | } |
| 1015 | } |
| 1016 | |
| 1017 | fprintf(ofd, |
| 1018 | "--------------------------- END NETLINK MESSAGE " |
| 1019 | "---------------------------\n"); |
| 1020 | } |
| 1021 | |
| 1022 | /** @} */ |
| 1023 | |
| 1024 | /** @} */ |