324 lines
8.8 KiB
C
324 lines
8.8 KiB
C
/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
|
|
|
|
/***
|
|
This file is part of systemd.
|
|
|
|
Copyright 2010 Lennart Poettering
|
|
|
|
systemd is free software; you can redistribute it and/or modify it
|
|
under the terms of the GNU Lesser General Public License as published by
|
|
the Free Software Foundation; either version 2.1 of the License, or
|
|
(at your option) any later version.
|
|
|
|
systemd is distributed in the hope that it will be useful, but
|
|
WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public License
|
|
along with systemd; If not, see <http://www.gnu.org/licenses/>.
|
|
***/
|
|
|
|
#include <stdlib.h>
|
|
#include <errno.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
#include <sys/capability.h>
|
|
|
|
#ifdef HAVE_SELINUX
|
|
#include <selinux/selinux.h>
|
|
#endif
|
|
|
|
#include "util.h"
|
|
#include "condition.h"
|
|
#include "virt.h"
|
|
|
|
Condition* condition_new(ConditionType type, const char *parameter, bool trigger, bool negate) {
|
|
Condition *c;
|
|
|
|
assert(type < _CONDITION_TYPE_MAX);
|
|
|
|
c = new0(Condition, 1);
|
|
if (!c)
|
|
return NULL;
|
|
|
|
c->type = type;
|
|
c->trigger = trigger;
|
|
c->negate = negate;
|
|
|
|
if (parameter) {
|
|
c->parameter = strdup(parameter);
|
|
if (!c->parameter) {
|
|
free(c);
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
return c;
|
|
}
|
|
|
|
void condition_free(Condition *c) {
|
|
assert(c);
|
|
|
|
free(c->parameter);
|
|
free(c);
|
|
}
|
|
|
|
void condition_free_list(Condition *first) {
|
|
Condition *c, *n;
|
|
|
|
LIST_FOREACH_SAFE(conditions, c, n, first)
|
|
condition_free(c);
|
|
}
|
|
|
|
static bool test_kernel_command_line(const char *parameter) {
|
|
char *line, *w, *state, *word = NULL;
|
|
bool equal;
|
|
int r;
|
|
size_t l, pl;
|
|
bool found = false;
|
|
|
|
assert(parameter);
|
|
|
|
if (detect_container(NULL) > 0)
|
|
return false;
|
|
|
|
r = read_one_line_file("/proc/cmdline", &line);
|
|
if (r < 0) {
|
|
log_warning("Failed to read /proc/cmdline, ignoring: %s", strerror(-r));
|
|
return false;
|
|
}
|
|
|
|
equal = !!strchr(parameter, '=');
|
|
pl = strlen(parameter);
|
|
|
|
FOREACH_WORD_QUOTED(w, l, line, state) {
|
|
|
|
free(word);
|
|
word = strndup(w, l);
|
|
if (!word)
|
|
break;
|
|
|
|
if (equal) {
|
|
if (streq(word, parameter)) {
|
|
found = true;
|
|
break;
|
|
}
|
|
} else {
|
|
if (startswith(word, parameter) && (word[pl] == '=' || word[pl] == 0)) {
|
|
found = true;
|
|
break;
|
|
}
|
|
}
|
|
|
|
}
|
|
|
|
free(word);
|
|
free(line);
|
|
|
|
return found;
|
|
}
|
|
|
|
static bool test_virtualization(const char *parameter) {
|
|
int b;
|
|
Virtualization v;
|
|
const char *id;
|
|
|
|
assert(parameter);
|
|
|
|
v = detect_virtualization(&id);
|
|
if (v < 0) {
|
|
log_warning("Failed to detect virtualization, ignoring: %s", strerror(-v));
|
|
return false;
|
|
}
|
|
|
|
/* First, compare with yes/no */
|
|
b = parse_boolean(parameter);
|
|
|
|
if (v > 0 && b > 0)
|
|
return true;
|
|
|
|
if (v == 0 && b == 0)
|
|
return true;
|
|
|
|
/* Then, compare categorization */
|
|
if (v == VIRTUALIZATION_VM && streq(parameter, "vm"))
|
|
return true;
|
|
|
|
if (v == VIRTUALIZATION_CONTAINER && streq(parameter, "container"))
|
|
return true;
|
|
|
|
/* Finally compare id */
|
|
return v > 0 && streq(parameter, id);
|
|
}
|
|
|
|
static bool test_security(const char *parameter) {
|
|
#ifdef HAVE_SELINUX
|
|
if (streq(parameter, "selinux"))
|
|
return is_selinux_enabled() > 0;
|
|
#endif
|
|
return false;
|
|
}
|
|
|
|
static bool test_capability(const char *parameter) {
|
|
cap_value_t value;
|
|
FILE *f;
|
|
char line[LINE_MAX];
|
|
unsigned long long capabilities = (unsigned long long) -1;
|
|
|
|
/* If it's an invalid capability, we don't have it */
|
|
|
|
if (cap_from_name(parameter, &value) < 0)
|
|
return false;
|
|
|
|
/* If it's a valid capability we default to assume
|
|
* that we have it */
|
|
|
|
f = fopen("/proc/self/status", "re");
|
|
if (!f)
|
|
return true;
|
|
|
|
while (fgets(line, sizeof(line), f)) {
|
|
truncate_nl(line);
|
|
|
|
if (startswith(line, "CapBnd:")) {
|
|
(void) sscanf(line+7, "%llx", &capabilities);
|
|
break;
|
|
}
|
|
}
|
|
|
|
fclose(f);
|
|
|
|
return !!(capabilities & (1ULL << value));
|
|
}
|
|
|
|
bool condition_test(Condition *c) {
|
|
assert(c);
|
|
|
|
switch(c->type) {
|
|
|
|
case CONDITION_PATH_EXISTS:
|
|
return (access(c->parameter, F_OK) >= 0) == !c->negate;
|
|
|
|
case CONDITION_PATH_EXISTS_GLOB:
|
|
return (glob_exists(c->parameter) > 0) == !c->negate;
|
|
|
|
case CONDITION_PATH_IS_DIRECTORY: {
|
|
struct stat st;
|
|
|
|
if (stat(c->parameter, &st) < 0)
|
|
return c->negate;
|
|
return S_ISDIR(st.st_mode) == !c->negate;
|
|
}
|
|
|
|
case CONDITION_PATH_IS_SYMBOLIC_LINK: {
|
|
struct stat st;
|
|
|
|
if (lstat(c->parameter, &st) < 0)
|
|
return c->negate;
|
|
return S_ISLNK(st.st_mode) == !c->negate;
|
|
}
|
|
|
|
case CONDITION_PATH_IS_MOUNT_POINT:
|
|
return (path_is_mount_point(c->parameter, true) > 0) == !c->negate;
|
|
|
|
case CONDITION_DIRECTORY_NOT_EMPTY: {
|
|
int k;
|
|
|
|
k = dir_is_empty(c->parameter);
|
|
return !(k == -ENOENT || k > 0) == !c->negate;
|
|
}
|
|
|
|
case CONDITION_FILE_IS_EXECUTABLE: {
|
|
struct stat st;
|
|
|
|
if (stat(c->parameter, &st) < 0)
|
|
return c->negate;
|
|
|
|
return (S_ISREG(st.st_mode) && (st.st_mode & 0111)) == !c->negate;
|
|
}
|
|
|
|
case CONDITION_KERNEL_COMMAND_LINE:
|
|
return test_kernel_command_line(c->parameter) == !c->negate;
|
|
|
|
case CONDITION_VIRTUALIZATION:
|
|
return test_virtualization(c->parameter) == !c->negate;
|
|
|
|
case CONDITION_SECURITY:
|
|
return test_security(c->parameter) == !c->negate;
|
|
|
|
case CONDITION_CAPABILITY:
|
|
return test_capability(c->parameter) == !c->negate;
|
|
|
|
case CONDITION_NULL:
|
|
return !c->negate;
|
|
|
|
default:
|
|
assert_not_reached("Invalid condition type.");
|
|
}
|
|
}
|
|
|
|
bool condition_test_list(Condition *first) {
|
|
Condition *c;
|
|
int triggered = -1;
|
|
|
|
/* If the condition list is empty, then it is true */
|
|
if (!first)
|
|
return true;
|
|
|
|
/* Otherwise, if all of the non-trigger conditions apply and
|
|
* if any of the trigger conditions apply (unless there are
|
|
* none) we return true */
|
|
LIST_FOREACH(conditions, c, first) {
|
|
bool b;
|
|
|
|
b = condition_test(c);
|
|
|
|
if (!c->trigger && !b)
|
|
return false;
|
|
|
|
if (c->trigger && triggered <= 0)
|
|
triggered = b;
|
|
}
|
|
|
|
return triggered != 0;
|
|
}
|
|
|
|
void condition_dump(Condition *c, FILE *f, const char *prefix) {
|
|
assert(c);
|
|
assert(f);
|
|
|
|
if (!prefix)
|
|
prefix = "";
|
|
|
|
fprintf(f,
|
|
"%s\t%s: %s%s%s\n",
|
|
prefix,
|
|
condition_type_to_string(c->type),
|
|
c->trigger ? "|" : "",
|
|
c->negate ? "!" : "",
|
|
c->parameter);
|
|
}
|
|
|
|
void condition_dump_list(Condition *first, FILE *f, const char *prefix) {
|
|
Condition *c;
|
|
|
|
LIST_FOREACH(conditions, c, first)
|
|
condition_dump(c, f, prefix);
|
|
}
|
|
|
|
static const char* const condition_type_table[_CONDITION_TYPE_MAX] = {
|
|
[CONDITION_PATH_EXISTS] = "ConditionPathExists",
|
|
[CONDITION_PATH_EXISTS_GLOB] = "ConditionPathExistsGlob",
|
|
[CONDITION_PATH_IS_DIRECTORY] = "ConditionPathIsDirectory",
|
|
[CONDITION_PATH_IS_SYMBOLIC_LINK] = "ConditionPathIsSymbolicLink",
|
|
[CONDITION_PATH_IS_MOUNT_POINT] = "ConditionPathIsMountPoint",
|
|
[CONDITION_DIRECTORY_NOT_EMPTY] = "ConditionDirectoryNotEmpty",
|
|
[CONDITION_KERNEL_COMMAND_LINE] = "ConditionKernelCommandLine",
|
|
[CONDITION_VIRTUALIZATION] = "ConditionVirtualization",
|
|
[CONDITION_SECURITY] = "ConditionSecurity",
|
|
[CONDITION_NULL] = "ConditionNull"
|
|
};
|
|
|
|
DEFINE_STRING_TABLE_LOOKUP(condition_type, ConditionType);
|