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/* A lot of code from jail.c in */
/* TODO: Attribute properly */
#include <sys/types.h>
#include <sys/param.h>
#include <sys/jail.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <paths.h>
#include <stdio.h>
#include <err.h>
#include <unistd.h>
#include <limits.h>
#ifdef HAVE_CONFIG_H
#include "../config.h"
#endif
#define START_SCRIPT "/etc/rc"
static char* START_ARGS[] = { _PATH_BSHELL, START_SCRIPT };
static void usage();
static void check_command(const char* cmd);
static void run_command(const char* cmd, char* args[]);
int main(int argc, char* argv[])
{
int ch;
struct jail j;
struct in_addr in;
argc--;
argv++;
if(argc < 3)
usage();
if(getuid() != 0)
errx(1, "must be run as root");
if(chdir(argv[0]) != 0)
err(1, "couldn't change to jail directory: %s", argv[0]);
if(inet_aton(argv[2], &in) != 1)
errx(1, "invalid ip address: %s", argv[2]);
memset(&j, 0, sizeof(j));
j.version = 0;
j.path = argv[0];
j.hostname = argv[1];
j.ip_number = ntohl(in.s_addr);
/* Here's where we actually go into the jail */
if(jail(&j) != 0)
err(1, "couldn't create jail");
argc -= 3;
argv += 3;
if(argc == 0)
{
check_command(START_SCRIPT);
run_command(START_ARGS[0], START_ARGS);
}
else
{
check_command(argv[0]);
run_command(argv[0], argv);
}
return 0;
}
static void usage()
{
fprintf(stderr, "usage: jstart path hostname ip-number [command ...]\n");
exit(2);
}
static void check_command(const char* cmd)
{
struct stat sb;
if(stat(cmd, &sb) == -1)
{
if(errno == EACCES || errno == ELOOP || errno == ENAMETOOLONG ||
errno == ENOENT || errno == ENOTDIR)
{
err(1, "can't execute in jail: %s", cmd);
}
err(1, "couldn't stat file: %s", cmd);
}
if(!(sb.st_mode & S_IFREG))
errx(1, "not a regular file: %s", cmd);
if(sb.st_uid != 0)
errx(1, "not owned by root: %s", cmd);
}
static void run_command(const char* cmd, char* args[])
{
char* env[5];
char* t;
int j;
memset(env, 0, sizeof(env));
#define MAKE_ENV_VAR(n) \
t = getenv(n); \
if(t != NULL) \
{ \
env[j] = alloca(strlen(n) + 2 + strlen(t)); \
sprintf(env[j], "%s=%s", (char*)(n), t); \
j++; \
}
/* Prepare an environment for the cmd */
env[0] = "PATH=" _PATH_STDPATH;
j = 1;
MAKE_ENV_VAR("TERM");
MAKE_ENV_VAR("COLUMNS");
MAKE_ENV_VAR("LINES");
if(execve(cmd, args, env) != 0)
err("couldn't execute command: %s", cmd);
}
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