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-rw-r--r--src/core/selinux-access.c283
1 files changed, 0 insertions, 283 deletions
diff --git a/src/core/selinux-access.c b/src/core/selinux-access.c
deleted file mode 100644
index 2b96a9551b..0000000000
--- a/src/core/selinux-access.c
+++ /dev/null
@@ -1,283 +0,0 @@
-/***
- This file is part of systemd.
-
- Copyright 2012 Dan Walsh
-
- 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 "selinux-access.h"
-
-#ifdef HAVE_SELINUX
-
-#include <errno.h>
-#include <selinux/avc.h>
-#include <selinux/selinux.h>
-#include <stdio.h>
-#ifdef HAVE_AUDIT
-#include <libaudit.h>
-#endif
-
-#include "sd-bus.h"
-
-#include "alloc-util.h"
-#include "audit-fd.h"
-#include "bus-util.h"
-#include "log.h"
-#include "path-util.h"
-#include "selinux-util.h"
-#include "stdio-util.h"
-#include "strv.h"
-#include "util.h"
-
-static bool initialized = false;
-
-struct audit_info {
- sd_bus_creds *creds;
- const char *path;
- const char *cmdline;
-};
-
-/*
- Any time an access gets denied this callback will be called
- with the audit data. We then need to just copy the audit data into the msgbuf.
-*/
-static int audit_callback(
- void *auditdata,
- security_class_t cls,
- char *msgbuf,
- size_t msgbufsize) {
-
- const struct audit_info *audit = auditdata;
- uid_t uid = 0, login_uid = 0;
- gid_t gid = 0;
- char login_uid_buf[DECIMAL_STR_MAX(uid_t) + 1] = "n/a";
- char uid_buf[DECIMAL_STR_MAX(uid_t) + 1] = "n/a";
- char gid_buf[DECIMAL_STR_MAX(gid_t) + 1] = "n/a";
-
- if (sd_bus_creds_get_audit_login_uid(audit->creds, &login_uid) >= 0)
- xsprintf(login_uid_buf, UID_FMT, login_uid);
- if (sd_bus_creds_get_euid(audit->creds, &uid) >= 0)
- xsprintf(uid_buf, UID_FMT, uid);
- if (sd_bus_creds_get_egid(audit->creds, &gid) >= 0)
- xsprintf(gid_buf, GID_FMT, gid);
-
- snprintf(msgbuf, msgbufsize,
- "auid=%s uid=%s gid=%s%s%s%s%s%s%s",
- login_uid_buf, uid_buf, gid_buf,
- audit->path ? " path=\"" : "", strempty(audit->path), audit->path ? "\"" : "",
- audit->cmdline ? " cmdline=\"" : "", strempty(audit->cmdline), audit->cmdline ? "\"" : "");
-
- return 0;
-}
-
-static int callback_type_to_priority(int type) {
- switch(type) {
-
- case SELINUX_ERROR:
- return LOG_ERR;
-
- case SELINUX_WARNING:
- return LOG_WARNING;
-
- case SELINUX_INFO:
- return LOG_INFO;
-
- case SELINUX_AVC:
- default:
- return LOG_NOTICE;
- }
-}
-
-/*
- libselinux uses this callback when access gets denied or other
- events happen. If audit is turned on, messages will be reported
- using audit netlink, otherwise they will be logged using the usual
- channels.
-
- Code copied from dbus and modified.
-*/
-_printf_(2, 3) static int log_callback(int type, const char *fmt, ...) {
- va_list ap;
- const char *fmt2;
-
-#ifdef HAVE_AUDIT
- int fd;
-
- fd = get_audit_fd();
-
- if (fd >= 0) {
- _cleanup_free_ char *buf = NULL;
- int r;
-
- va_start(ap, fmt);
- r = vasprintf(&buf, fmt, ap);
- va_end(ap);
-
- if (r >= 0) {
- audit_log_user_avc_message(fd, AUDIT_USER_AVC, buf, NULL, NULL, NULL, 0);
- return 0;
- }
- }
-#endif
-
- fmt2 = strjoina("selinux: ", fmt);
-
- va_start(ap, fmt);
- log_internalv(LOG_AUTH | callback_type_to_priority(type), 0, __FILE__, __LINE__, __FUNCTION__, fmt2, ap);
- va_end(ap);
-
- return 0;
-}
-
-static int access_init(sd_bus_error *error) {
-
- if (!mac_selinux_use())
- return 0;
-
- if (initialized)
- return 1;
-
- if (avc_open(NULL, 0) != 0) {
- int enforce, saved_errno = errno;
-
- enforce = security_getenforce();
- log_full_errno(enforce != 0 ? LOG_ERR : LOG_WARNING, saved_errno, "Failed to open the SELinux AVC: %m");
-
- /* If enforcement isn't on, then let's suppress this
- * error, and just don't do any AVC checks. The
- * warning we printed is hence all the admin will
- * see. */
- if (enforce == 0)
- return 0;
-
- /* Return an access denied error, if we couldn't load
- * the AVC but enforcing mode was on, or we couldn't
- * determine whether it is one. */
- return sd_bus_error_setf(error, SD_BUS_ERROR_ACCESS_DENIED, "Failed to open the SELinux AVC: %s", strerror(saved_errno));
- }
-
- selinux_set_callback(SELINUX_CB_AUDIT, (union selinux_callback) audit_callback);
- selinux_set_callback(SELINUX_CB_LOG, (union selinux_callback) log_callback);
-
- initialized = true;
- return 1;
-}
-
-/*
- This function communicates with the kernel to check whether or not it should
- allow the access.
- If the machine is in permissive mode it will return ok. Audit messages will
- still be generated if the access would be denied in enforcing mode.
-*/
-int mac_selinux_generic_access_check(
- sd_bus_message *message,
- const char *path,
- const char *permission,
- sd_bus_error *error) {
-
- _cleanup_(sd_bus_creds_unrefp) sd_bus_creds *creds = NULL;
- const char *tclass = NULL, *scon = NULL;
- struct audit_info audit_info = {};
- _cleanup_free_ char *cl = NULL;
- char *fcon = NULL;
- char **cmdline = NULL;
- int r = 0;
-
- assert(message);
- assert(permission);
- assert(error);
-
- r = access_init(error);
- if (r <= 0)
- return r;
-
- r = sd_bus_query_sender_creds(
- message,
- SD_BUS_CREDS_PID|SD_BUS_CREDS_EUID|SD_BUS_CREDS_EGID|
- SD_BUS_CREDS_CMDLINE|SD_BUS_CREDS_AUDIT_LOGIN_UID|
- SD_BUS_CREDS_SELINUX_CONTEXT|
- SD_BUS_CREDS_AUGMENT /* get more bits from /proc */,
- &creds);
- if (r < 0)
- goto finish;
-
- /* The SELinux context is something we really should have
- * gotten directly from the message or sender, and not be an
- * augmented field. If it was augmented we cannot use it for
- * authorization, since this is racy and vulnerable. Let's add
- * an extra check, just in case, even though this really
- * shouldn't be possible. */
- assert_return((sd_bus_creds_get_augmented_mask(creds) & SD_BUS_CREDS_SELINUX_CONTEXT) == 0, -EPERM);
-
- r = sd_bus_creds_get_selinux_context(creds, &scon);
- if (r < 0)
- goto finish;
-
- if (path) {
- /* Get the file context of the unit file */
-
- r = getfilecon_raw(path, &fcon);
- if (r < 0) {
- r = sd_bus_error_setf(error, SD_BUS_ERROR_ACCESS_DENIED, "Failed to get file context on %s.", path);
- goto finish;
- }
-
- tclass = "service";
- } else {
- r = getcon_raw(&fcon);
- if (r < 0) {
- r = sd_bus_error_setf(error, SD_BUS_ERROR_ACCESS_DENIED, "Failed to get current context.");
- goto finish;
- }
-
- tclass = "system";
- }
-
- sd_bus_creds_get_cmdline(creds, &cmdline);
- cl = strv_join(cmdline, " ");
-
- audit_info.creds = creds;
- audit_info.path = path;
- audit_info.cmdline = cl;
-
- r = selinux_check_access(scon, fcon, tclass, permission, &audit_info);
- if (r < 0)
- r = sd_bus_error_setf(error, SD_BUS_ERROR_ACCESS_DENIED, "SELinux policy denies access.");
-
- log_debug("SELinux access check scon=%s tcon=%s tclass=%s perm=%s path=%s cmdline=%s: %i", scon, fcon, tclass, permission, path, cl, r);
-
-finish:
- freecon(fcon);
-
- if (r < 0 && security_getenforce() != 1) {
- sd_bus_error_free(error);
- r = 0;
- }
-
- return r;
-}
-
-#else
-
-int mac_selinux_generic_access_check(
- sd_bus_message *message,
- const char *path,
- const char *permission,
- sd_bus_error *error) {
-
- return 0;
-}
-
-#endif
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-01 13:46:09 +0000