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