code.delx.au - pulseaudio/blob - src/pulsecore/authkey.c

   1 /* $Id$ */
   2
   3 /***
   4   This file is part of PulseAudio.
   5
   6   PulseAudio is free software; you can redistribute it and/or modify
   7   it under the terms of the GNU Lesser General Public License as
   8   published by the Free Software Foundation; either version 2.1 of the
   9   License, or (at your option) any later version.
  10
  11   PulseAudio is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   Lesser General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public
  17   License along with PulseAudio; if not, write to the Free Software
  18   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  19   USA.
  20 ***/
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include <config.h>
  24 #endif
  25
  26 #include <assert.h>
  27 #include <unistd.h>
  28 #include <fcntl.h>
  29 #include <string.h>
  30 #include <errno.h>
  31 #include <stdio.h>
  32 #include <inttypes.h>
  33 #include <stdlib.h>
  34 #include <time.h>
  35 #include <limits.h>
  36 #include <sys/stat.h>
  37
  38 #include <pulse/util.h>
  39 #include <pulsecore/core-error.h>
  40 #include <pulsecore/core-util.h>
  41 #include <pulsecore/log.h>
  42 #include <pulsecore/random.h>
  43
  44 #include "authkey.h"
  45
  46 /* Generate a new authorization key, store it in file fd and return it in *data  */
  47 static int generate(int fd, void *ret_data, size_t length) {
  48     ssize_t r;
  49     assert(fd >= 0 && ret_data && length);
  50
  51     pa_random(ret_data, length);
  52
  53     lseek(fd, 0, SEEK_SET);
  54     ftruncate(fd, 0);
  55
  56     if ((r = pa_loop_write(fd, ret_data, length)) < 0 || (size_t) r != length) {
  57         pa_log(__FILE__": failed to write cookie file: %s", pa_cstrerror(errno));
  58         return -1;
  59     }
  60
  61     return 0;
  62 }
  63
  64 #ifndef O_BINARY
  65 #define O_BINARY 0
  66 #endif
  67
  68 /* Load an euthorization cookie from file fn and store it in data. If
  69  * the cookie file doesn't exist, create it */
  70 static int load(const char *fn, void *data, size_t length) {
  71     int fd = -1;
  72     int writable = 1;
  73     int unlock = 0, ret = -1;
  74     ssize_t r;
  75     assert(fn && data && length);
  76
  77     if ((fd = open(fn, O_RDWR|O_CREAT|O_BINARY, S_IRUSR|S_IWUSR)) < 0) {
  78         if (errno != EACCES || (fd = open(fn, O_RDONLY|O_BINARY)) < 0) {
  79             pa_log(__FILE__": failed to open cookie file '%s': %s", fn, pa_cstrerror(errno));
  80             goto finish;
  81         } else
  82             writable = 0;
  83     }
  84
  85     unlock = pa_lock_fd(fd, 1) >= 0;
  86
  87     if ((r = pa_loop_read(fd, data, length)) < 0) {
  88         pa_log(__FILE__": failed to read cookie file '%s': %s", fn, pa_cstrerror(errno));
  89         goto finish;
  90     }
  91
  92     if ((size_t) r != length) {
  93         pa_log_debug(__FILE__": got %d bytes from cookie file '%s', expected %d", (int)r, fn, (int)length);
  94
  95         if (!writable) {
  96             pa_log(__FILE__": unable to write cookie to read only file");
  97             goto finish;
  98         }
  99
 100         if (generate(fd, data, length) < 0)
 101             goto finish;
 102     }
 103
 104     ret = 0;
 105
 106 finish:
 107
 108     if (fd >= 0) {
 109
 110         if (unlock)
 111             pa_lock_fd(fd, 0);
 112
 113         close(fd);
 114     }
 115
 116     return ret;
 117 }
 118
 119 /* Load a cookie from a cookie file. If the file doesn't exist, create it. */
 120 int pa_authkey_load(const char *path, void *data, size_t length) {
 121     int ret;
 122
 123     assert(path && data && length);
 124
 125     ret = load(path, data, length);
 126
 127     if (ret < 0)
 128         pa_log(__FILE__": Failed to load authorization key '%s': %s", path,
 129                (ret == -1) ? pa_cstrerror(errno) : "file corrupt");
 130
 131     return ret;
 132 }
 133
 134 /* If the specified file path starts with / return it, otherwise
 135  * return path prepended with home directory */
 136 static const char *normalize_path(const char *fn, char *s, size_t l) {
 137     assert(fn && s && l > 0);
 138
 139 #ifndef OS_IS_WIN32
 140     if (fn[0] != '/') {
 141 #else
 142     if (strlen(fn) < 3 || !isalpha(fn[0]) || fn[1] != ':' || fn[2] != '\\') {
 143 #endif
 144         char homedir[PATH_MAX];
 145         if (!pa_get_home_dir(homedir, sizeof(homedir)))
 146             return NULL;
 147
 148 #ifndef OS_IS_WIN32
 149         snprintf(s, l, "%s/%s", homedir, fn);
 150 #else
 151         snprintf(s, l, "%s\\%s", homedir, fn);
 152 #endif
 153         return s;
 154     }
 155
 156     return fn;
 157 }
 158
 159 /* Load a cookie from a file in the home directory. If the specified
 160  * path starts with /, use it as absolute path instead. */
 161 int pa_authkey_load_auto(const char *fn, void *data, size_t length) {
 162     char path[PATH_MAX];
 163     const char *p;
 164     assert(fn && data && length);
 165
 166     if (!(p = normalize_path(fn, path, sizeof(path))))
 167         return -2;
 168
 169     return pa_authkey_load(p, data, length);
 170 }
 171
 172 /* Store the specified cookie in the speicified cookie file */
 173 int pa_authkey_save(const char *fn, const void *data, size_t length) {
 174     int fd = -1;
 175     int unlock = 0, ret = -1;
 176     ssize_t r;
 177     char path[PATH_MAX];
 178     const char *p;
 179     assert(fn && data && length);
 180
 181     if (!(p = normalize_path(fn, path, sizeof(path))))
 182         return -2;
 183
 184     if ((fd = open(p, O_RDWR|O_CREAT, S_IRUSR|S_IWUSR)) < 0) {
 185         pa_log(__FILE__": failed to open cookie file '%s': %s", fn, pa_cstrerror(errno));
 186         goto finish;
 187     }
 188
 189     unlock = pa_lock_fd(fd, 1) >= 0;
 190
 191     if ((r = pa_loop_write(fd, data, length)) < 0 || (size_t) r != length) {
 192         pa_log(__FILE__": failed to read cookie file '%s': %s", fn, pa_cstrerror(errno));
 193         goto finish;
 194     }
 195
 196     ret = 0;
 197
 198 finish:
 199
 200     if (fd >= 0) {
 201
 202         if (unlock)
 203             pa_lock_fd(fd, 0);
 204
 205         close(fd);
 206     }
 207
 208     return ret;
 209 }