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