smack-setup: extract rule writing into a separate function

Check all errors.
This commit is contained in:
Zbigniew Jędrzejewski-Szmek 2013-03-13 23:23:06 -04:00
parent faeffa73a8
commit a4783bd17a

View file

@ -39,66 +39,95 @@
#include "log.h"
#include "label.h"
#define ACCESSES_D_PATH "/etc/smack/accesses.d/"
#define SMACK_CONFIG "/etc/smack/accesses.d/"
int smack_setup(void) {
_cleanup_fclose_ FILE *smack = NULL;
static int write_rules(const char* dstpath, const char* srcdir) {
_cleanup_fclose_ FILE *dst = NULL;
_cleanup_closedir_ DIR *dir = NULL;
struct dirent *entry;
char buf[NAME_MAX];
int dfd = -1;
int r = 0;
smack = fopen("/sys/fs/smackfs/load2", "we");
if (!smack) {
if (errno == ENOENT)
log_debug("Smack is not enabled in the kernel, not loading access rules.");
else
log_warning("Failed to open /sys/fs/smackfs/load2: %m");
return 0;
dst = fopen(dstpath, "we");
if (!dst) {
if (errno != ENOENT)
log_warning("Failed to open %s: %m", dstpath);
return -errno; /* negative error */
}
/* write rules to load2 from every file in the directory */
dir = opendir(ACCESSES_D_PATH);
/* write rules to dst from every file in the directory */
dir = opendir(srcdir);
if (!dir) {
log_full(errno == ENOENT ? LOG_DEBUG : LOG_WARNING,
"Opening Smack access rules directory "
ACCESSES_D_PATH ": %m");
return 0;
if (errno != ENOENT)
log_warning("Failed to opendir %s: %m", srcdir);
return errno; /* positive on purpose */
}
dfd = dirfd(dir);
assert(dfd >= 0);
FOREACH_DIRENT(entry, dir, return 0) {
int fd;
_cleanup_fclose_ FILE *policy = NULL;
_cleanup_close_ int pol = -1;
pol = openat(dfd, entry->d_name, O_RDONLY|O_CLOEXEC);
if (pol < 0) {
log_error("Smack access rule file %s not opened: %m",
entry->d_name);
fd = openat(dfd, entry->d_name, O_RDONLY|O_CLOEXEC);
if (fd < 0) {
if (r == 0)
r = -errno;
log_warning("Failed to open %s: %m", entry->d_name);
continue;
}
policy = fdopen(pol, "re");
policy = fdopen(fd, "re");
if (!policy) {
log_error("Smack access rule file %s not opened: %m",
entry->d_name);
if (r == 0)
r = -errno;
close_nointr_nofail(fd);
log_error("Failed to open %s: %m", entry->d_name);
continue;
}
pol = -1;
/* load2 write rules in the kernel require a line buffered stream */
FOREACH_LINE(buf, policy,
log_error("Failed to read from Smack access rule file %s: %m",
log_error("Failed to read line from %s: %m",
entry->d_name)) {
fputs(buf, smack);
fflush(smack);
if (!fputs(buf, dst)) {
if (r == 0)
r = -EINVAL;
log_error("Failed to write line to %s", dstpath);
break;
}
if (fflush(dst)) {
if (r == 0)
r = -errno;
log_error("Failed to flush writes to %s: %m", dstpath);
break;
}
}
}
log_info("Successfully loaded Smack policies.");
return 0;
return r;
}
int smack_setup(void) {
int r;
r = write_rules("/sys/fs/smackfs/load2", SMACK_CONFIG);
switch(r) {
case -ENOENT:
log_debug("Smack is not enabled in the kernel.");
return 0;
case ENOENT:
log_debug("Smack access rules directory " SMACK_CONFIG " not found");
return 0;
case 0:
log_info("Successfully loaded Smack policies.");
return 0;
default:
log_warning("Failed to load smack access rules: %s, ignoring.",
strerror(abs(r)));
return 0;
}
}