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#include "jailtest.h"
#include <dirent.h>
#include <sys/wait.h>
typedef struct {
char *tfile;
char *tdir;
} TestDir;
#define MAX_TEST_FILES 16
TestDir td[MAX_TEST_FILES];
static int files_cnt = 0;
void access_setup(const char *directory) {
// I am root!
assert(directory);
assert(user_home_dir);
if (files_cnt >= MAX_TEST_FILES) {
fprintf(stderr, "Error: maximum number of test directories exceded\n");
exit(1);
}
char *fname = strdup(directory);
if (!fname)
errExit("strdup");
if (strncmp(fname, "~/", 2) == 0) {
free(fname);
if (asprintf(&fname, "%s/%s", user_home_dir, directory + 2) == -1)
errExit("asprintf");
}
char *path = realpath(fname, NULL);
free(fname);
if (path == NULL) {
fprintf(stderr, "Warning: invalid directory %s, skipping...\n", directory);
return;
}
// file in home directory
if (strncmp(path, user_home_dir, strlen(user_home_dir)) != 0) {
fprintf(stderr, "Warning: file %s is not in user home directory, skipping...\n", directory);
free(path);
return;
}
// try to open the dir as root
DIR *dir = opendir(path);
if (!dir) {
fprintf(stderr, "Warning: directory %s not found, skipping\n", directory);
free(path);
return;
}
closedir(dir);
// create a test file
char *test_file;
if (asprintf(&test_file, "%s/jailtest-access-%d", path, getpid()) == -1)
errExit("asprintf");
FILE *fp = fopen(test_file, "w");
if (!fp) {
printf("Warning: I cannot create test file in directory %s, skipping...\n", directory);
return;
}
fprintf(fp, "this file was created by firetest utility, you can safely delete it\n");
fclose(fp);
int rv = chown(test_file, user_uid, user_gid);
if (rv)
errExit("chown");
char *dname = strdup(directory);
if (!dname)
errExit("strdup");
td[files_cnt].tdir = dname;
td[files_cnt].tfile = test_file;
files_cnt++;
}
void access_destroy(void) {
// remove test files
int i;
for (i = 0; i < files_cnt; i++) {
int rv = unlink(td[i].tfile);
(void) rv;
}
files_cnt = 0;
}
void access_test(void) {
// I am root in sandbox mount namespace
assert(user_uid);
int i;
pid_t child = fork();
if (child == -1)
errExit("fork");
if (child == 0) { // child
// drop privileges
if (setgid(user_gid) != 0)
errExit("setgid");
if (setuid(user_uid) != 0)
errExit("setuid");
for (i = 0; i < files_cnt; i++) {
assert(td[i].tfile);
// try to open the file for reading
FILE *fp = fopen(td[i].tfile, "r");
if (fp) {
printf(" Warning: I can read %s\n", td[i].tdir);
fclose(fp);
}
}
exit(0);
}
// wait for the child to finish
int status;
wait(&status);
}
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