Systemd/src/core/ima-setup.c
Zbigniew Jędrzejewski-Szmek ca78ad1de9 headers: remove unneeded includes from util.h
This means we need to include many more headers in various files that simply
included util.h before, but it seems cleaner to do it this way.
2019-03-27 11:53:12 +01:00

93 lines
3 KiB
C

/* SPDX-License-Identifier: LGPL-2.1+ */
/***
Copyright © 2012 Roberto Sassu - Politecnico di Torino, Italy
TORSEC group — http://security.polito.it
***/
#include <errno.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include "alloc-util.h"
#include "fd-util.h"
#include "fileio.h"
#include "ima-setup.h"
#include "log.h"
#define IMA_SECFS_DIR "/sys/kernel/security/ima"
#define IMA_SECFS_POLICY IMA_SECFS_DIR "/policy"
#define IMA_POLICY_PATH "/etc/ima/ima-policy"
int ima_setup(void) {
#if ENABLE_IMA
_cleanup_fclose_ FILE *input = NULL;
_cleanup_close_ int imafd = -1;
unsigned lineno = 0;
int r;
if (access(IMA_SECFS_DIR, F_OK) < 0) {
log_debug_errno(errno, "IMA support is disabled in the kernel, ignoring: %m");
return 0;
}
if (access(IMA_SECFS_POLICY, W_OK) < 0) {
log_warning_errno(errno, "Another IMA custom policy has already been loaded, ignoring: %m");
return 0;
}
if (access(IMA_POLICY_PATH, F_OK) < 0) {
log_debug_errno(errno, "No IMA custom policy file "IMA_POLICY_PATH", ignoring: %m");
return 0;
}
imafd = open(IMA_SECFS_POLICY, O_WRONLY|O_CLOEXEC);
if (imafd < 0) {
log_error_errno(errno, "Failed to open the IMA kernel interface "IMA_SECFS_POLICY", ignoring: %m");
return 0;
}
/* attempt to write the name of the policy file into sysfs file */
if (write(imafd, IMA_POLICY_PATH, STRLEN(IMA_POLICY_PATH)) > 0)
goto done;
/* fall back to copying the policy line-by-line */
input = fopen(IMA_POLICY_PATH, "re");
if (!input) {
log_warning_errno(errno, "Failed to open the IMA custom policy file "IMA_POLICY_PATH", ignoring: %m");
return 0;
}
safe_close(imafd);
imafd = open(IMA_SECFS_POLICY, O_WRONLY|O_CLOEXEC);
if (imafd < 0) {
log_error_errno(errno, "Failed to open the IMA kernel interface "IMA_SECFS_POLICY", ignoring: %m");
return 0;
}
for (;;) {
_cleanup_free_ char *line = NULL;
size_t len;
r = read_line(input, LONG_LINE_MAX, &line);
if (r < 0)
return log_error_errno(r, "Failed to read the IMA custom policy file "IMA_POLICY_PATH": %m");
if (r == 0)
break;
len = strlen(line);
lineno++;
if (len > 0 && write(imafd, line, len) < 0)
return log_error_errno(errno, "Failed to load the IMA custom policy file "IMA_POLICY_PATH"%u: %m",
lineno);
}
done:
log_info("Successfully loaded the IMA custom policy "IMA_POLICY_PATH".");
#endif /* ENABLE_IMA */
return 0;
}