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diff -ur vixie-cron-4.1/Makefile vixie-cron-4.1-selinux/Makefile
--- vixie-cron-4.1/Makefile 2004-08-28 02:09:33.000000000 +0800
+++ vixie-cron-4.1-selinux/Makefile 2017-04-26 22:16:53.321394815 +0800
@@ -68,7 +68,8 @@
#<<want to use a nonstandard CC?>>
CC = gcc -Wall -Wno-unused -Wno-comment
#<<manifest defines>>
-DEFS =
+DEFS = -s -DWITH_SELINUX
+LIBS += -lselinux
#(SGI IRIX systems need this)
#DEFS = -D_BSD_SIGNALS -Dconst=
#<<the name of the BSD-like install program>>
diff -ur vixie-cron-4.1/database.c vixie-cron-4.1-selinux/database.c
--- vixie-cron-4.1/database.c 2004-08-28 02:09:34.000000000 +0800
+++ vixie-cron-4.1-selinux/database.c 2017-04-27 01:31:34.757942605 +0800
@@ -28,6 +28,15 @@
#include "cron.h"
+#ifdef WITH_SELINUX
+#include <selinux/selinux.h>
+#include <selinux/context.h>
+#include <selinux/get_context_list.h>
+#define SYSUSERNAME "system_u"
+#else
+#define SYSUSERNAME "*system*"
+#endif
+
#define TMAX(a,b) ((a)>(b)?(a):(b))
static void process_crontab(const char *, const char *,
@@ -183,7 +192,7 @@
if (fname == NULL) {
/* must be set to something for logging purposes.
*/
- fname = "*system*";
+ fname = SYSUSERNAME;
} else if ((pw = getpwnam(uname)) == NULL) {
/* file doesn't have a user in passwd file.
*/
@@ -245,6 +254,117 @@
free_user(u);
log_it(fname, getpid(), "RELOAD", tabname);
}
+#ifdef WITH_SELINUX
+ if (is_selinux_enabled()) {
+ security_context_t file_context=NULL;
+ security_context_t user_context=NULL;
+ context_t current_context = NULL;
+ char *current_context_str = NULL;
+ struct av_decision avd;
+ int retval=0;
+ char *seuser=NULL;
+ char *level=NULL;
+ int sys_user = 0;
+
+ sys_user = strcmp(SYSUSERNAME, fname);
+
+ if (fgetfilecon(crontab_fd, &file_context) < OK) {
+ log_it(fname, getpid(), "getfilecon FAILED", tabname);
+ goto next_crontab;
+ }
+
+ if (sys_user != 0) {
+ if (getseuserbyname(fname, &seuser, &level) < 0) {
+ log_it(fname, getpid(), "NO SEUSER", tabname);
+ goto next_crontab;
+ }
+ } else {
+ if (getcon(¤t_context_str) < 0) {
+ log_it(fname, getpid(), "getcon FAILED", tabname);
+ goto next_crontab;
+ }
+
+ current_context = context_new(current_context_str);
+ if (current_context == 0) {
+ log_it(fname, getpid(), "context new FAILED", tabname);
+ freecon(current_context_str);
+ goto next_crontab;
+ }
+
+ seuser = context_user_get(current_context);
+ level = context_range_get(current_context);
+ }
+
+ if (get_default_context_with_level(seuser, level, NULL, &user_context) < 0) {
+ log_it(fname, getpid(), "NO CONTEXT", tabname);
+ freecon(file_context);
+ if (sys_user != 0) {
+ free(seuser);
+ free(level);
+ }
+ freecon(current_context_str);
+ context_free(current_context);
+ goto next_crontab;
+ }
+
+ /*
+ * Since crontab files are not directly executed,
+ * crond must ensure that the crontab file has
+ * a context that is appropriate for the context of
+ * the user cron job. It performs an entrypoint
+ * permission check for this purpose.
+ */
+ security_class_t file_class;
+ access_vector_t entrypoint_bit;
+ file_class = string_to_security_class("file");
+ if (file_class == 0) {
+ log_it(fname, getpid(), "file CLASS NOT DEFINED", tabname);
+ freecon(current_context_str);
+ context_free(current_context);
+ freecon(user_context);
+ freecon(file_context);
+ if (sys_user != 0) {
+ free(seuser);
+ free(level);
+ }
+ goto next_crontab;
+ }
+
+ entrypoint_bit = string_to_av_perm(file_class, "entrypoint");
+ if (entrypoint_bit == 0) {
+ log_it(fname, getpid(), "file:entrypoint AV NOT DEFINED", tabname);
+ freecon(current_context_str);
+ context_free(current_context);
+ freecon(user_context);
+ freecon(file_context);
+ if (sys_user != 0) {
+ free(seuser);
+ free(level);
+ }
+ goto next_crontab;
+ }
+
+ retval = security_compute_av_raw(user_context,
+ file_context,
+ file_class,
+ entrypoint_bit,
+ &avd);
+
+ freecon(user_context);
+ freecon(file_context);
+ if (sys_user != 0) {
+ free(seuser);
+ free(level);
+ }
+ context_free(current_context);
+ freecon(current_context_str);
+
+ if (retval || ((entrypoint_bit & avd.allowed) != entrypoint_bit)) {
+ log_it(fname, getpid(), "ENTRYPOINT FAILED", tabname);
+ goto next_crontab;
+ }
+ }
+#endif
u = load_user(crontab_fd, pw, fname);
if (u != NULL) {
u->mtime = statbuf->st_mtime;
diff -ur vixie-cron-4.1/do_command.c vixie-cron-4.1-selinux/do_command.c
--- vixie-cron-4.1/do_command.c 2004-08-28 02:09:34.000000000 +0800
+++ vixie-cron-4.1-selinux/do_command.c 2017-04-27 01:30:49.045144698 +0800
@@ -25,6 +25,12 @@
#include "cron.h"
+#ifdef WITH_SELINUX
+#include <selinux/selinux.h>
+#include <selinux/context.h>
+#include <selinux/get_context_list.h>
+#endif
+
static void child_process(entry *, user *);
static int safe_p(const char *, const char *);
@@ -265,6 +271,49 @@
_exit(OK_EXIT);
}
# endif /*DEBUGGING*/
+#ifdef WITH_SELINUX
+ if (is_selinux_enabled()) {
+ char *seuser = NULL;
+ char *level = NULL;
+ char *current_context_str = NULL;
+ security_context_t scontext;
+ context_t current_context = NULL;
+
+ if (strcmp("system_u", u->name) != 0) {
+ if (getseuserbyname(u->name, &seuser, &level) < 0) {
+ fprintf(stderr, "getseuserbyname: Could not determine seuser for user %s\n", u->name);
+ _exit(ERROR_EXIT);
+ }
+ } else {
+ if (getcon(¤t_context_str) < 0) {
+ fprintf(stderr, "getcon FAILED\n");
+ _exit(ERROR_EXIT);
+ }
+
+ current_context = context_new(current_context_str);
+ if (current_context == NULL) {
+ fprintf(stderr, "failed to create new context: %s\n", current_context_str);
+ freecon(current_context_str);
+ _exit(ERROR_EXIT);
+ }
+
+ seuser = context_user_get(current_context);
+ }
+
+ if (get_default_context_with_level(seuser, level, NULL, &scontext) < 0) {
+ fprintf(stderr, "get_default_context_with_level: could not get security context for user %s, seuser %s\n", u->name, seuser);
+ _exit(ERROR_EXIT);
+ }
+
+ if (setexeccon(scontext) < 0) {
+ fprintf(stderr, "setexeccon: Could not set exec context to %s for user %s\n", scontext, u->name);
+ _exit(ERROR_EXIT);
+ }
+ free(seuser);
+ free(level);
+ freecon(scontext);
+ }
+#endif
execle(shell, shell, "-c", e->cmd, (char *)0, e->envp);
fprintf(stderr, "execl: couldn't exec `%s'\n", shell);
perror("execl");
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