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