src/shared/condition-util.c

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2010 Lennart Poettering
   7
   8   systemd is free software; you can redistribute it and/or modify it
   9   under the terms of the GNU Lesser General Public License as published by
  10   the Free Software Foundation; either version 2.1 of the License, or
  11   (at your option) any later version.
  12
  13   systemd is distributed in the hope that it will be useful, but
  14   WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16   Lesser General Public License for more details.
  17
  18   You should have received a copy of the GNU Lesser General Public License
  19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  20 ***/
  21
  22 #include <stdlib.h>
  23 #include <errno.h>
  24 #include <string.h>
  25 #include <unistd.h>
  26 #include <sys/statvfs.h>
  27 #include <fnmatch.h>
  28
  29 #include <systemd/sd-id128.h>
  30 #include "util.h"
  31 #include "condition-util.h"
  32 #include "virt.h"
  33 #include "path-util.h"
  34 #include "fileio.h"
  35 #include "unit.h"
  36 #include "architecture.h"
  37
  38 Condition* condition_new(ConditionType type, const char *parameter, bool trigger, bool negate) {
  39         Condition *c;
  40
  41         assert(type < _CONDITION_TYPE_MAX);
  42
  43         c = new0(Condition, 1);
  44         if (!c)
  45                 return NULL;
  46
  47         c->type = type;
  48         c->trigger = trigger;
  49         c->negate = negate;
  50
  51         if (parameter) {
  52                 c->parameter = strdup(parameter);
  53                 if (!c->parameter) {
  54                         free(c);
  55                         return NULL;
  56                 }
  57         }
  58
  59         return c;
  60 }
  61
  62 void condition_free(Condition *c) {
  63         assert(c);
  64
  65         free(c->parameter);
  66         free(c);
  67 }
  68
  69 void condition_free_list(Condition *first) {
  70         Condition *c, *n;
  71
  72         LIST_FOREACH_SAFE(conditions, c, n, first)
  73                 condition_free(c);
  74 }
  75
  76 bool condition_test_kernel_command_line(Condition *c) {
  77         char *line, *w, *state, *word = NULL;
  78         bool equal;
  79         int r;
  80         size_t l, pl;
  81         bool found = false;
  82
  83         assert(c);
  84         assert(c->parameter);
  85         assert(c->type == CONDITION_KERNEL_COMMAND_LINE);
  86
  87         r = proc_cmdline(&line);
  88         if (r < 0)
  89                 log_warning("Failed to read /proc/cmdline, ignoring: %s", strerror(-r));
  90         if (r <= 0)
  91                 return c->negate;
  92
  93         equal = !!strchr(c->parameter, '=');
  94         pl = strlen(c->parameter);
  95
  96         FOREACH_WORD_QUOTED(w, l, line, state) {
  97
  98                 free(word);
  99                 word = strndup(w, l);
 100                 if (!word)
 101                         break;
 102
 103                 if (equal) {
 104                         if (streq(word, c->parameter)) {
 105                                 found = true;
 106                                 break;
 107                         }
 108                 } else {
 109                         if (startswith(word, c->parameter) && (word[pl] == '=' || word[pl] == 0)) {
 110                                 found = true;
 111                                 break;
 112                         }
 113                 }
 114
 115         }
 116
 117         free(word);
 118         free(line);
 119
 120         return found == !c->negate;
 121 }
 122
 123 bool condition_test_virtualization(Condition *c) {
 124         int b, v;
 125         const char *id;
 126
 127         assert(c);
 128         assert(c->parameter);
 129         assert(c->type == CONDITION_VIRTUALIZATION);
 130
 131         v = detect_virtualization(&id);
 132         if (v < 0) {
 133                 log_warning("Failed to detect virtualization, ignoring: %s", strerror(-v));
 134                 return c->negate;
 135         }
 136
 137         /* First, compare with yes/no */
 138         b = parse_boolean(c->parameter);
 139
 140         if (v > 0 && b > 0)
 141                 return !c->negate;
 142
 143         if (v == 0 && b == 0)
 144                 return !c->negate;
 145
 146         /* Then, compare categorization */
 147         if (v == VIRTUALIZATION_VM && streq(c->parameter, "vm"))
 148                 return !c->negate;
 149
 150         if (v == VIRTUALIZATION_CONTAINER && streq(c->parameter, "container"))
 151                 return !c->negate;
 152
 153         /* Finally compare id */
 154         return (v > 0 && streq(c->parameter, id)) == !c->negate;
 155 }
 156
 157 bool condition_test_architecture(Condition *c) {
 158         Architecture a, b;
 159
 160         assert(c);
 161         assert(c->parameter);
 162         assert(c->type == CONDITION_ARCHITECTURE);
 163
 164         a = uname_architecture();
 165         if (a < 0)
 166                 return c->negate;
 167
 168         if (streq(c->parameter, "native"))
 169                 b = native_architecture();
 170         else
 171                 b = architecture_from_string(c->parameter);
 172
 173         if (b < 0)
 174                 return c->negate;
 175
 176         return (a == b) == !c->negate;
 177 }
 178
 179 bool condition_test_host(Condition *c) {
 180         _cleanup_free_ char *h = NULL;
 181         sd_id128_t x, y;
 182         int r;
 183
 184         assert(c);
 185         assert(c->parameter);
 186         assert(c->type == CONDITION_HOST);
 187
 188         if (sd_id128_from_string(c->parameter, &x) >= 0) {
 189
 190                 r = sd_id128_get_machine(&y);
 191                 if (r < 0)
 192                         return c->negate;
 193
 194                 return sd_id128_equal(x, y) == !c->negate;
 195         }
 196
 197         h = gethostname_malloc();
 198         if (!h)
 199                 return c->negate;
 200
 201         return (fnmatch(c->parameter, h, FNM_CASEFOLD) == 0) == !c->negate;
 202 }
 203
 204 bool condition_test_ac_power(Condition *c) {
 205         int r;
 206
 207         assert(c);
 208         assert(c->parameter);
 209         assert(c->type == CONDITION_AC_POWER);
 210
 211         r = parse_boolean(c->parameter);
 212         if (r < 0)
 213                 return !c->negate;
 214
 215         return ((on_ac_power() != 0) == !!r) == !c->negate;
 216 }
 217
 218 void condition_dump(Condition *c, FILE *f, const char *prefix) {
 219         assert(c);
 220         assert(f);
 221
 222         if (!prefix)
 223                 prefix = "";
 224
 225         fprintf(f,
 226                 "%s\t%s: %s%s%s %s\n",
 227                 prefix,
 228                 condition_type_to_string(c->type),
 229                 c->trigger ? "|" : "",
 230                 c->negate ? "!" : "",
 231                 c->parameter,
 232                 c->state < 0 ? "failed" : c->state > 0 ? "succeeded" : "untested");
 233 }
 234
 235 void condition_dump_list(Condition *first, FILE *f, const char *prefix) {
 236         Condition *c;
 237
 238         LIST_FOREACH(conditions, c, first)
 239                 condition_dump(c, f, prefix);
 240 }
 241
 242 static const char* const condition_type_table[_CONDITION_TYPE_MAX] = {
 243         [CONDITION_PATH_EXISTS] = "ConditionPathExists",
 244         [CONDITION_PATH_EXISTS_GLOB] = "ConditionPathExistsGlob",
 245         [CONDITION_PATH_IS_DIRECTORY] = "ConditionPathIsDirectory",
 246         [CONDITION_PATH_IS_SYMBOLIC_LINK] = "ConditionPathIsSymbolicLink",
 247         [CONDITION_PATH_IS_MOUNT_POINT] = "ConditionPathIsMountPoint",
 248         [CONDITION_PATH_IS_READ_WRITE] = "ConditionPathIsReadWrite",
 249         [CONDITION_DIRECTORY_NOT_EMPTY] = "ConditionDirectoryNotEmpty",
 250         [CONDITION_FILE_NOT_EMPTY] = "ConditionFileNotEmpty",
 251         [CONDITION_FILE_IS_EXECUTABLE] = "ConditionFileIsExecutable",
 252         [CONDITION_KERNEL_COMMAND_LINE] = "ConditionKernelCommandLine",
 253         [CONDITION_VIRTUALIZATION] = "ConditionVirtualization",
 254         [CONDITION_SECURITY] = "ConditionSecurity",
 255         [CONDITION_CAPABILITY] = "ConditionCapability",
 256         [CONDITION_HOST] = "ConditionHost",
 257         [CONDITION_AC_POWER] = "ConditionACPower",
 258         [CONDITION_ARCHITECTURE] = "ConditionArchitecture",
 259         [CONDITION_NEEDS_UPDATE] = "ConditionNeedsUpdate",
 260         [CONDITION_NULL] = "ConditionNull"
 261 };
 262
 263 DEFINE_STRING_TABLE_LOOKUP(condition_type, ConditionType);