src/client/sock.c

   1 /*
   2  * SysDB - src/client/sock.c
   3  * Copyright (C) 2013 Sebastian 'tokkee' Harl <sh@tokkee.org>
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  16  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  17  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  18  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR
  19  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  20  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  21  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
  22  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  23  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  24  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  25  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  */
  27
  28 #if HAVE_CONFIG_H
  29 #       include "config.h"
  30 #endif /* HAVE_CONFIG_H */
  31
  32 #include "client/sock.h"
  33 #include "utils/error.h"
  34 #include "utils/strbuf.h"
  35 #include "utils/proto.h"
  36 #include "utils/os.h"
  37 #include "utils/ssl.h"
  38
  39 #include <arpa/inet.h>
  40
  41 #include <assert.h>
  42 #include <errno.h>
  43 #include <limits.h>
  44
  45 #include <stdlib.h>
  46
  47 #include <string.h>
  48 #include <strings.h>
  49
  50 #include <unistd.h>
  51
  52 #include <sys/socket.h>
  53 #include <sys/un.h>
  54
  55 #include <netdb.h>
  56
  57 /*
  58  * private data types
  59  */
  60
  61 struct sdb_client {
  62         char *address;
  63         int   fd;
  64         bool  eof;
  65
  66         /* optional SSL settings */
  67         sdb_ssl_client_t *ssl;
  68         sdb_ssl_session_t *ssl_session;
  69
  70         ssize_t (*read)(sdb_client_t *, sdb_strbuf_t *, size_t);
  71         ssize_t (*write)(sdb_client_t *, const void *, size_t);
  72 };
  73
  74 /*
  75  * private helper functions
  76  */
  77
  78 static ssize_t
  79 ssl_read(sdb_client_t *client, sdb_strbuf_t *buf, size_t n)
  80 {
  81         char tmp[n];
  82         ssize_t ret;
  83
  84         ret = sdb_ssl_session_read(client->ssl_session, tmp, n);
  85         if (ret <= 0)
  86                 return ret;
  87
  88         sdb_strbuf_memappend(buf, tmp, ret);
  89         return ret;
  90 } /* ssl_read */
  91
  92 static ssize_t
  93 ssl_write(sdb_client_t *client, const void *buf, size_t n)
  94 {
  95         return sdb_ssl_session_write(client->ssl_session, buf, n);
  96 } /* ssl_write */
  97
  98 static ssize_t
  99 client_read(sdb_client_t *client, sdb_strbuf_t *buf, size_t n)
 100 {
 101         return sdb_strbuf_read(buf, client->fd, n);
 102 } /* client_read */
 103
 104 static ssize_t
 105 client_write(sdb_client_t *client, const void *buf, size_t n)
 106 {
 107         return sdb_write(client->fd, n, buf);
 108 } /* client_write */
 109
 110 static int
 111 connect_unixsock(sdb_client_t *client, const char *address)
 112 {
 113         struct sockaddr_un sa;
 114
 115         client->fd = socket(AF_UNIX, SOCK_STREAM, /* protocol = */ 0);
 116         if (client->fd < 0) {
 117                 char errbuf[1024];
 118                 sdb_log(SDB_LOG_ERR, "Failed to open socket: %s",
 119                                 sdb_strerror(errno, errbuf, sizeof(errbuf)));
 120                 return -1;
 121         }
 122
 123         sa.sun_family = AF_UNIX;
 124         strncpy(sa.sun_path, address, sizeof(sa.sun_path));
 125         sa.sun_path[sizeof(sa.sun_path) - 1] = '\0';
 126
 127         if (connect(client->fd, (struct sockaddr *)&sa, sizeof(sa))) {
 128                 char errbuf[1024];
 129                 sdb_client_close(client);
 130                 sdb_log(SDB_LOG_ERR, "Failed to connect to '%s': %s",
 131                                 sa.sun_path, sdb_strerror(errno, errbuf, sizeof(errbuf)));
 132                 return -1;
 133         }
 134         return client->fd;
 135 } /* connect_unixsock */
 136
 137 static int
 138 connect_tcp(sdb_client_t *client, const char *address)
 139 {
 140         struct addrinfo *ai, *ai_list = NULL;
 141         int status;
 142
 143         if ((status = sdb_resolve(SDB_NET_TCP, address, &ai_list))) {
 144                 sdb_log(SDB_LOG_ERR, "Failed to resolve '%s': %s",
 145                                 address, gai_strerror(status));
 146                 return -1;
 147         }
 148
 149         for (ai = ai_list; ai != NULL; ai = ai->ai_next) {
 150                 client->fd = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
 151                 if (client->fd < 0) {
 152                         char errbuf[1024];
 153                         sdb_log(SDB_LOG_ERR, "Failed to open socket: %s",
 154                                         sdb_strerror(errno, errbuf, sizeof(errbuf)));
 155                         continue;
 156                 }
 157
 158                 if (connect(client->fd, ai->ai_addr, ai->ai_addrlen)) {
 159                         char host[1024], port[32], errbuf[1024];
 160                         sdb_client_close(client);
 161                         getnameinfo(ai->ai_addr, ai->ai_addrlen, host, sizeof(host),
 162                                         port, sizeof(port), NI_NUMERICHOST | NI_NUMERICSERV);
 163                         sdb_log(SDB_LOG_ERR, "Failed to connect to '%s:%s': %s",
 164                                         host, port, sdb_strerror(errno, errbuf, sizeof(errbuf)));
 165                         continue;
 166                 }
 167                 break;
 168         }
 169         freeaddrinfo(ai_list);
 170
 171         if (client->fd < 0)
 172                 return -1;
 173
 174         /* TODO: make options configurable */
 175         client->ssl = sdb_ssl_client_create(NULL);
 176         if (! client->ssl) {
 177                 sdb_client_close(client);
 178                 return -1;
 179         }
 180         client->ssl_session = sdb_ssl_client_connect(client->ssl, client->fd);
 181         if (! client->ssl_session) {
 182                 sdb_client_close(client);
 183                 return -1;
 184         }
 185
 186         client->read = ssl_read;
 187         client->write = ssl_write;
 188         return client->fd;
 189 } /* connect_tcp */
 190
 191 /*
 192  * public API
 193  */
 194
 195 sdb_client_t *
 196 sdb_client_create(const char *address)
 197 {
 198         sdb_client_t *client;
 199
 200         if (! address)
 201                 return NULL;
 202
 203         client = malloc(sizeof(*client));
 204         if (! client) {
 205                 sdb_log(SDB_LOG_ERR, "Out of memory");
 206                 return NULL;
 207         }
 208         memset(client, 0, sizeof(*client));
 209         client->fd = -1;
 210         client->eof = 1;
 211
 212         client->ssl = NULL;
 213         client->read = client_read;
 214         client->write = client_write;
 215
 216         client->address = strdup(address);
 217         if (! client->address) {
 218                 sdb_client_destroy(client);
 219                 sdb_log(SDB_LOG_ERR, "Out of memory");
 220                 return NULL;
 221         }
 222
 223         return client;
 224 } /* sdb_client_create */
 225
 226 void
 227 sdb_client_destroy(sdb_client_t *client)
 228 {
 229         if (! client)
 230                 return;
 231
 232         sdb_client_close(client);
 233
 234         if (client->address)
 235                 free(client->address);
 236         client->address = NULL;
 237
 238         free(client);
 239 } /* sdb_client_destroy */
 240
 241 int
 242 sdb_client_connect(sdb_client_t *client, const char *username)
 243 {
 244         sdb_strbuf_t *buf;
 245         ssize_t status;
 246         uint32_t rstatus;
 247
 248         if ((! client) || (! client->address))
 249                 return -1;
 250
 251         if (client->fd >= 0)
 252                 return -1;
 253
 254         if (*client->address == '/')
 255                 connect_unixsock(client, client->address);
 256         else if (!strncasecmp(client->address, "unix:", strlen("unix:")))
 257                 connect_unixsock(client, client->address + strlen("unix:"));
 258         else if (!strncasecmp(client->address, "tcp:", strlen("tcp:")))
 259                 connect_tcp(client, client->address + strlen("tcp:"));
 260         else
 261                 connect_tcp(client, client->address);
 262
 263         if (client->fd < 0)
 264                 return -1;
 265         client->eof = 0;
 266
 267         /* XXX */
 268         if (! username)
 269                 username = "";
 270
 271         buf = sdb_strbuf_create(64);
 272         rstatus = 0;
 273         status = sdb_client_rpc(client, SDB_CONNECTION_STARTUP,
 274                         (uint32_t)strlen(username), username, &rstatus, buf);
 275         if ((status >= 0) && (rstatus == SDB_CONNECTION_OK)) {
 276                 sdb_strbuf_destroy(buf);
 277                 return 0;
 278         }
 279
 280         if (status < 0) {
 281                 sdb_log(SDB_LOG_ERR, "%s", sdb_strbuf_string(buf));
 282                 sdb_client_close(client);
 283                 sdb_strbuf_destroy(buf);
 284                 return (int)status;
 285         }
 286         if (client->eof)
 287                 sdb_log(SDB_LOG_ERR, "Encountered end-of-file while waiting "
 288                                 "for server response");
 289
 290         if (rstatus == SDB_CONNECTION_ERROR) {
 291                 sdb_log(SDB_LOG_ERR, "Access denied for user '%s': %s",
 292                                 username, sdb_strbuf_string(buf));
 293                 status = -((int)rstatus);
 294         }
 295         else if (rstatus != SDB_CONNECTION_OK) {
 296                 sdb_log(SDB_LOG_ERR, "Received unsupported authentication request "
 297                                 "(status %d) during startup", (int)rstatus);
 298                 status = -((int)rstatus);
 299         }
 300
 301         sdb_client_close(client);
 302         sdb_strbuf_destroy(buf);
 303         return (int)status;
 304 } /* sdb_client_connect */
 305
 306 int
 307 sdb_client_sockfd(sdb_client_t *client)
 308 {
 309         if (! client)
 310                 return -1;
 311         return client->fd;
 312 } /* sdb_client_sockfd */
 313
 314 int
 315 sdb_client_shutdown(sdb_client_t *client, int how)
 316 {
 317         if (! client) {
 318                 errno = ENOTSOCK;
 319                 return -1;
 320         }
 321
 322         if (client->fd < 0) {
 323                 errno = EBADF;
 324                 return -1;
 325         }
 326
 327         return shutdown(client->fd, how);
 328 } /* sdb_client_shutdown */
 329
 330 void
 331 sdb_client_close(sdb_client_t *client)
 332 {
 333         if (! client)
 334                 return;
 335
 336         if (client->ssl_session) {
 337                 sdb_ssl_session_destroy(client->ssl_session);
 338                 client->ssl_session = NULL;
 339         }
 340         if (client->ssl) {
 341                 sdb_ssl_client_destroy(client->ssl);
 342                 client->ssl = NULL;
 343         }
 344
 345         close(client->fd);
 346         client->fd = -1;
 347         client->eof = 1;
 348 } /* sdb_client_close */
 349
 350 ssize_t
 351 sdb_client_rpc(sdb_client_t *client,
 352                 uint32_t cmd, uint32_t msg_len, const char *msg,
 353                 uint32_t *code, sdb_strbuf_t *buf)
 354 {
 355         uint32_t rcode = 0;
 356         ssize_t status;
 357
 358         if (! buf)
 359                 return -1;
 360
 361         if (sdb_client_send(client, cmd, msg_len, msg) < 0) {
 362                 char errbuf[1024];
 363                 sdb_strbuf_sprintf(buf, "Failed to send %s message to server: %s",
 364                                 SDB_CONN_MSGTYPE_TO_STRING(cmd),
 365                                 sdb_strerror(errno, errbuf, sizeof(errbuf)));
 366                 if (code)
 367                         *code = SDB_CONNECTION_ERROR;
 368                 return -1;
 369         }
 370
 371         while (42) {
 372                 size_t offset = sdb_strbuf_len(buf);
 373
 374                 status = sdb_client_recv(client, &rcode, buf);
 375                 if (status < 0) {
 376                         char errbuf[1024];
 377                         sdb_strbuf_sprintf(buf, "Failed to receive server response: %s",
 378                                         sdb_strerror(errno, errbuf, sizeof(errbuf)));
 379                         if (code)
 380                                 *code = SDB_CONNECTION_ERROR;
 381                         return status;
 382                 }
 383
 384                 if (rcode == SDB_CONNECTION_LOG) {
 385                         uint32_t prio = 0;
 386                         if (sdb_proto_unmarshal_int32(SDB_STRBUF_STR(buf), &prio) < 0) {
 387                                 sdb_log(SDB_LOG_WARNING, "Received a LOG message "
 388                                                 "with invalid or missing priority");
 389                                 prio = (uint32_t)SDB_LOG_ERR;
 390                         }
 391                         sdb_log((int)prio, "%s", sdb_strbuf_string(buf) + offset);
 392                         sdb_strbuf_skip(buf, offset, sdb_strbuf_len(buf) - offset);
 393                         continue;
 394                 }
 395                 break;
 396         }
 397
 398         if (code)
 399                 *code = rcode;
 400         return status;
 401 } /* sdb_client_rpc */
 402
 403 ssize_t
 404 sdb_client_send(sdb_client_t *client,
 405                 uint32_t cmd, uint32_t msg_len, const char *msg)
 406 {
 407         char buf[2 * sizeof(uint32_t) + msg_len];
 408
 409         if ((! client) || (! client->fd))
 410                 return -1;
 411         if (sdb_proto_marshal(buf, sizeof(buf), cmd, msg_len, msg) < 0)
 412                 return -1;
 413
 414         return client->write(client, buf, sizeof(buf));
 415 } /* sdb_client_send */
 416
 417 ssize_t
 418 sdb_client_recv(sdb_client_t *client,
 419                 uint32_t *code, sdb_strbuf_t *buf)
 420 {
 421         uint32_t rstatus = UINT32_MAX;
 422         uint32_t rlen = UINT32_MAX;
 423
 424         size_t total = 0;
 425         size_t req = 2 * sizeof(uint32_t);
 426
 427         size_t data_offset = sdb_strbuf_len(buf);
 428
 429         if (code)
 430                 *code = UINT32_MAX;
 431
 432         if ((! client) || (! client->fd) || (! buf)) {
 433                 errno = EBADF;
 434                 return -1;
 435         }
 436
 437         while (42) {
 438                 ssize_t status;
 439
 440                 errno = 0;
 441                 status = client->read(client, buf, req);
 442                 if (status < 0) {
 443                         if ((errno == EAGAIN) || (errno == EWOULDBLOCK))
 444                                 continue;
 445                         return status;
 446                 }
 447                 else if (! status) {
 448                         client->eof = 1;
 449                         break;
 450                 }
 451
 452                 total += (size_t)status;
 453
 454                 if (total != req)
 455                         continue;
 456
 457                 if (rstatus == UINT32_MAX) {
 458                         const char *str = sdb_strbuf_string(buf) + data_offset;
 459                         size_t len = sdb_strbuf_len(buf) - data_offset;
 460                         ssize_t n;
 461
 462                         /* retrieve status and data len */
 463                         assert(len >= 2 * sizeof(uint32_t));
 464                         n = sdb_proto_unmarshal_int32(str, len, &rstatus);
 465                         str += n; len -= (size_t)n;
 466                         sdb_proto_unmarshal_int32(str, len, &rlen);
 467
 468                         if (! rlen)
 469                                 break;
 470
 471                         req = (size_t)rlen;
 472                         total = 0;
 473                 }
 474                 else /* finished reading data */
 475                         break;
 476         }
 477
 478         if (total != req) {
 479                 /* unexpected EOF; clear partially read data */
 480                 sdb_strbuf_skip(buf, data_offset, sdb_strbuf_len(buf));
 481                 return 0;
 482         }
 483
 484         if (rstatus != UINT32_MAX)
 485                 /* remove status,len */
 486                 sdb_strbuf_skip(buf, data_offset, 2 * sizeof(rstatus));
 487
 488         if (code)
 489                 *code = rstatus;
 490
 491         return (ssize_t)total;
 492 } /* sdb_client_recv */
 493
 494 bool
 495 sdb_client_eof(sdb_client_t *client)
 496 {
 497         if ((! client) || (client->fd < 0))
 498                 return 1;
 499         return client->eof;
 500 } /* sdb_client_eof */
 501
 502 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */
 503