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
  38 #include <arpa/inet.h>
  39
  40 #include <assert.h>
  41 #include <errno.h>
  42 #include <limits.h>
  43
  44 #include <stdlib.h>
  45
  46 #include <string.h>
  47 #include <strings.h>
  48
  49 #include <unistd.h>
  50
  51 #include <sys/socket.h>
  52 #include <sys/un.h>
  53
  54 #include <netdb.h>
  55
  56 /*
  57  * private data types
  58  */
  59
  60 struct sdb_client {
  61         char *address;
  62         int   fd;
  63         bool  eof;
  64
  65         ssize_t (*read)(sdb_client_t *, sdb_strbuf_t *, size_t);
  66         ssize_t (*write)(sdb_client_t *, const void *, size_t);
  67 };
  68
  69 /*
  70  * private helper functions
  71  */
  72
  73 static ssize_t
  74 client_read(sdb_client_t *client, sdb_strbuf_t *buf, size_t n)
  75 {
  76         return sdb_strbuf_read(buf, client->fd, n);
  77 } /* client_read */
  78
  79 static ssize_t
  80 client_write(sdb_client_t *client, const void *buf, size_t n)
  81 {
  82         return sdb_write(client->fd, n, buf);
  83 } /* client_write */
  84
  85 static int
  86 connect_unixsock(sdb_client_t *client, const char *address)
  87 {
  88         struct sockaddr_un sa;
  89
  90         client->fd = socket(AF_UNIX, SOCK_STREAM, /* protocol = */ 0);
  91         if (client->fd < 0) {
  92                 char errbuf[1024];
  93                 sdb_log(SDB_LOG_ERR, "Failed to open socket: %s",
  94                                 sdb_strerror(errno, errbuf, sizeof(errbuf)));
  95                 return -1;
  96         }
  97
  98         sa.sun_family = AF_UNIX;
  99         strncpy(sa.sun_path, address, sizeof(sa.sun_path));
 100         sa.sun_path[sizeof(sa.sun_path) - 1] = '\0';
 101
 102         if (connect(client->fd, (struct sockaddr *)&sa, sizeof(sa))) {
 103                 char errbuf[1024];
 104                 sdb_client_close(client);
 105                 sdb_log(SDB_LOG_ERR, "Failed to connect to '%s': %s",
 106                                 sa.sun_path, sdb_strerror(errno, errbuf, sizeof(errbuf)));
 107                 return -1;
 108         }
 109         return client->fd;
 110 } /* connect_unixsock */
 111
 112 static int
 113 connect_tcp(sdb_client_t *client, const char *address)
 114 {
 115         struct addrinfo *ai, *ai_list = NULL;
 116         int status;
 117
 118         if ((status = sdb_resolve(SDB_NET_TCP, address, &ai_list))) {
 119                 sdb_log(SDB_LOG_ERR, "Failed to resolve '%s': %s",
 120                                 address, gai_strerror(status));
 121                 return -1;
 122         }
 123
 124         for (ai = ai_list; ai != NULL; ai = ai->ai_next) {
 125                 client->fd = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
 126                 if (client->fd < 0) {
 127                         char errbuf[1024];
 128                         sdb_log(SDB_LOG_ERR, "Failed to open socket: %s",
 129                                         sdb_strerror(errno, errbuf, sizeof(errbuf)));
 130                         continue;
 131                 }
 132
 133                 if (connect(client->fd, ai->ai_addr, ai->ai_addrlen)) {
 134                         char host[1024], port[32], errbuf[1024];
 135                         sdb_client_close(client);
 136                         getnameinfo(ai->ai_addr, ai->ai_addrlen, host, sizeof(host),
 137                                         port, sizeof(port), NI_NUMERICHOST | NI_NUMERICSERV);
 138                         sdb_log(SDB_LOG_ERR, "Failed to connect to '%s:%s': %s",
 139                                         host, port, sdb_strerror(errno, errbuf, sizeof(errbuf)));
 140                         continue;
 141                 }
 142                 break;
 143         }
 144         freeaddrinfo(ai_list);
 145         return client->fd;
 146 } /* connect_tcp */
 147
 148 /*
 149  * public API
 150  */
 151
 152 sdb_client_t *
 153 sdb_client_create(const char *address)
 154 {
 155         sdb_client_t *client;
 156
 157         if (! address)
 158                 return NULL;
 159
 160         client = malloc(sizeof(*client));
 161         if (! client) {
 162                 sdb_log(SDB_LOG_ERR, "Out of memory");
 163                 return NULL;
 164         }
 165         memset(client, 0, sizeof(*client));
 166         client->fd = -1;
 167         client->eof = 1;
 168
 169         client->read = client_read;
 170         client->write = client_write;
 171
 172         client->address = strdup(address);
 173         if (! client->address) {
 174                 sdb_client_destroy(client);
 175                 sdb_log(SDB_LOG_ERR, "Out of memory");
 176                 return NULL;
 177         }
 178
 179         return client;
 180 } /* sdb_client_create */
 181
 182 void
 183 sdb_client_destroy(sdb_client_t *client)
 184 {
 185         if (! client)
 186                 return;
 187
 188         sdb_client_close(client);
 189
 190         if (client->address)
 191                 free(client->address);
 192         client->address = NULL;
 193
 194         free(client);
 195 } /* sdb_client_destroy */
 196
 197 int
 198 sdb_client_connect(sdb_client_t *client, const char *username)
 199 {
 200         sdb_strbuf_t *buf;
 201         ssize_t status;
 202         uint32_t rstatus;
 203
 204         if ((! client) || (! client->address))
 205                 return -1;
 206
 207         if (client->fd >= 0)
 208                 return -1;
 209
 210         if (*client->address == '/')
 211                 connect_unixsock(client, client->address);
 212         else if (!strncasecmp(client->address, "unix:", strlen("unix:")))
 213                 connect_unixsock(client, client->address + strlen("unix:"));
 214         else if (!strncasecmp(client->address, "tcp:", strlen("tcp:")))
 215                 connect_tcp(client, client->address + strlen("tcp:"));
 216         else
 217                 connect_tcp(client, client->address);
 218
 219         if (client->fd < 0)
 220                 return -1;
 221         client->eof = 0;
 222
 223         /* XXX */
 224         if (! username)
 225                 username = "";
 226
 227         status = sdb_client_send(client, SDB_CONNECTION_STARTUP,
 228                         (uint32_t)strlen(username), username);
 229         if (status < 0) {
 230                 char errbuf[1024];
 231                 sdb_client_close(client);
 232                 sdb_log(SDB_LOG_ERR, "Failed to send STARTUP message to server: %s",
 233                                 sdb_strerror(errno, errbuf, sizeof(errbuf)));
 234                 return (int)status;
 235         }
 236
 237         buf = sdb_strbuf_create(64);
 238         rstatus = 0;
 239         status = sdb_client_recv(client, &rstatus, buf);
 240         if ((status > 0) && (rstatus == SDB_CONNECTION_OK)) {
 241                 sdb_strbuf_destroy(buf);
 242                 return 0;
 243         }
 244
 245         if (status < 0) {
 246                 char errbuf[1024];
 247                 sdb_log(SDB_LOG_ERR, "Failed to receive server response: %s",
 248                                 sdb_strerror(errno, errbuf, sizeof(errbuf)));
 249         }
 250         else if (client->eof)
 251                 sdb_log(SDB_LOG_ERR, "Encountered end-of-file while waiting "
 252                                 "for server response");
 253
 254         if (rstatus == SDB_CONNECTION_ERROR) {
 255                 sdb_log(SDB_LOG_ERR, "Access denied for user '%s': %s",
 256                                 username, sdb_strbuf_string(buf));
 257                 status = -((int)rstatus);
 258         }
 259         else if (rstatus != SDB_CONNECTION_OK) {
 260                 sdb_log(SDB_LOG_ERR, "Received unsupported authentication request "
 261                                 "(status %d) during startup", (int)rstatus);
 262                 status = -((int)rstatus);
 263         }
 264
 265         sdb_client_close(client);
 266         sdb_strbuf_destroy(buf);
 267         return (int)status;
 268 } /* sdb_client_connect */
 269
 270 int
 271 sdb_client_sockfd(sdb_client_t *client)
 272 {
 273         if (! client)
 274                 return -1;
 275         return client->fd;
 276 } /* sdb_client_sockfd */
 277
 278 int
 279 sdb_client_shutdown(sdb_client_t *client, int how)
 280 {
 281         if (! client) {
 282                 errno = ENOTSOCK;
 283                 return -1;
 284         }
 285
 286         if (client->fd < 0) {
 287                 errno = EBADF;
 288                 return -1;
 289         }
 290
 291         return shutdown(client->fd, how);
 292 } /* sdb_client_shutdown */
 293
 294 void
 295 sdb_client_close(sdb_client_t *client)
 296 {
 297         if (! client)
 298                 return;
 299
 300         close(client->fd);
 301         client->fd = -1;
 302         client->eof = 1;
 303 } /* sdb_client_close */
 304
 305 ssize_t
 306 sdb_client_send(sdb_client_t *client,
 307                 uint32_t cmd, uint32_t msg_len, const char *msg)
 308 {
 309         char buf[2 * sizeof(uint32_t) + msg_len];
 310
 311         if ((! client) || (! client->fd))
 312                 return -1;
 313         if (sdb_proto_marshal(buf, sizeof(buf), cmd, msg_len, msg) < 0)
 314                 return -1;
 315
 316         return client->write(client, buf, sizeof(buf));
 317 } /* sdb_client_send */
 318
 319 ssize_t
 320 sdb_client_recv(sdb_client_t *client,
 321                 uint32_t *code, sdb_strbuf_t *buf)
 322 {
 323         uint32_t rstatus = UINT32_MAX;
 324         uint32_t rlen = UINT32_MAX;
 325
 326         size_t total = 0;
 327         size_t req = 2 * sizeof(uint32_t);
 328
 329         size_t data_offset = sdb_strbuf_len(buf);
 330
 331         if (code)
 332                 *code = UINT32_MAX;
 333
 334         if ((! client) || (! client->fd) || (! buf)) {
 335                 errno = EBADF;
 336                 return -1;
 337         }
 338
 339         while (42) {
 340                 ssize_t status;
 341
 342                 if (sdb_select(client->fd, SDB_SELECTIN))
 343                         return -1;
 344
 345                 errno = 0;
 346                 status = client->read(client, buf, req);
 347                 if (status < 0) {
 348                         if ((errno == EAGAIN) || (errno == EWOULDBLOCK))
 349                                 continue;
 350                         return status;
 351                 }
 352                 else if (! status) {
 353                         client->eof = 1;
 354                         break;
 355                 }
 356
 357                 total += (size_t)status;
 358
 359                 if (total != req)
 360                         continue;
 361
 362                 if (rstatus == UINT32_MAX) {
 363                         const char *str = sdb_strbuf_string(buf) + data_offset;
 364                         size_t len = sdb_strbuf_len(buf) - data_offset;
 365                         ssize_t n;
 366
 367                         /* retrieve status and data len */
 368                         assert(len >= 2 * sizeof(uint32_t));
 369                         n = sdb_proto_unmarshal_int32(str, len, &rstatus);
 370                         str += n; len -= (size_t)n;
 371                         sdb_proto_unmarshal_int32(str, len, &rlen);
 372
 373                         if (! rlen)
 374                                 break;
 375
 376                         req = (size_t)rlen;
 377                         total = 0;
 378                 }
 379                 else /* finished reading data */
 380                         break;
 381         }
 382
 383         if (total != req) {
 384                 /* unexpected EOF; clear partially read data */
 385                 sdb_strbuf_skip(buf, data_offset, sdb_strbuf_len(buf));
 386                 return 0;
 387         }
 388
 389         if (rstatus != UINT32_MAX)
 390                 /* remove status,len */
 391                 sdb_strbuf_skip(buf, data_offset, 2 * sizeof(rstatus));
 392
 393         if (code)
 394                 *code = rstatus;
 395
 396         return (ssize_t)total;
 397 } /* sdb_client_recv */
 398
 399 bool
 400 sdb_client_eof(sdb_client_t *client)
 401 {
 402         if ((! client) || (client->fd < 0))
 403                 return 1;
 404         return client->eof;
 405 } /* sdb_client_eof */
 406
 407 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */
 408