+++ /dev/null
-/*
- * Marc E. Fiuczynski <mef@cs.princeton.edu>
- *
- * Copyright (c) 2004 The Trustees of Princeton University (Trustees).
- *
- * Portions of this file are derived from the Paul Brett's vserver.c
- * modification to bash (vsh).
- *
- * It is free software; you can redistribute it and/or modify it under
- * the terms of the GNU General Public License as published by the
- * Free Software Foundation; either version 2, or (at your option) any
- * later version.
- *
- * It 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 General Public
- * License for more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with Poptop; see the file COPYING. If not, write to the Free Software
- * Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- */
-
-#ifdef HAVE_CONFIG_H
-# include <config.h>
-#endif
-#include "compat.h"
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <stdlib.h>
-#include <errno.h>
-#include <pwd.h>
-#include <unistd.h>
-#include <syscall.h>
-#include <sys/syscall.h>
-#include <asm/unistd.h>
-#include <sys/mount.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <ctype.h>
-
-#include "linuxcaps.h"
-#include "vserver.h"
-
-/* Null byte made explicit */
-#define NULLBYTE_SIZE 1
-
-/* Base for all vserver roots for chroot */
-#define VSERVER_ROOT_BASE "/vservers"
-
-
-/* Change to root:root (before entering new context) */
-static int setuidgid_root()
-{
- if (setgid(0) < 0) {
- fprintf(stderr, "setgid error\n");
- return -1;
- }
- if (setuid(0) < 0) {
- fprintf(stderr, "setuid error\n");
- return -1;
- }
- return 0;
-}
-
-static void compute_new_root(char *base, char **root, uid_t uid)
-{
- int root_len;
- struct passwd *pwd;
-
- if ((pwd = getpwuid(uid)) == NULL) {
- perror("vserver: getpwuid error ");
- exit(1);
- }
-
- root_len =
- strlen(base) + strlen("/") +
- strlen(pwd->pw_name) + NULLBYTE_SIZE;
- (*root) = (char *)malloc(root_len);
- if ((*root) == NULL) {
- perror("vserver: malloc error ");
- exit(1);
- }
-
- sprintf((*root), "%s/%s", base, pwd->pw_name);
- (*root)[root_len - 1] = '\0';
-}
-
-/* Example: sandbox_root = /vservers/bnc, relpath = /proc/1 */
-static int sandbox_file_exists(char *sandbox_root, char *relpath)
-{
- struct stat stat_buf;
- char *file;
- int len, exists = 0;
-
- len = strlen(sandbox_root) + strlen(relpath) + NULLBYTE_SIZE;
- if ((file = (char *)malloc(len)) == NULL) {
- perror("vserver: malloc error ");
- exit(1);
- }
- sprintf(file, "%s%s", sandbox_root, relpath);
- file[len - 1] = '\0';
- if (stat(file, &stat_buf) == 0) {
- exists = 1;
- }
-
-
- free(file);
- return exists;
-}
-
-static int proc_mounted(char *sandbox_root)
-{
- return sandbox_file_exists(sandbox_root, "/proc/1");
-}
-
-static int devpts_mounted(char *sandbox_root)
-{
- return sandbox_file_exists(sandbox_root, "/dev/pts/0");
-}
-
-static void mount_proc(char *sandbox_root,uid_t uid)
-{
- char *source = "/proc";
- char *target;
- int len;
-
- len = strlen(sandbox_root) + strlen("/") + strlen("proc") + NULLBYTE_SIZE;
- if ((target = (char *)malloc(len)) == NULL) {
- perror("vserver: malloc error ");
- exit(1);
- }
-
- sprintf(target, "%s/proc", sandbox_root);
- target[len - 1] = '\0';
- if (!proc_mounted(sandbox_root))
- mount(source, target, "proc", MS_BIND | MS_RDONLY, NULL);
-
- free(target);
-}
-
-static void mount_devpts(char *sandbox_root)
-{
- char *source = "/dev/pts";
- char *target;
- int len;
-
- len = strlen(sandbox_root) + strlen("/") + strlen("dev/pts") + NULLBYTE_SIZE;
- if ((target = (char *)malloc(len)) == NULL) {
- perror("vserver: malloc error ");
- exit(1);
- }
-
- sprintf(target, "%s/dev/pts", sandbox_root);
- target[len - 1] = '\0';
- if (!devpts_mounted(sandbox_root))
- mount(source, target, "devpts", 0, NULL);
-
- free(target);
-}
-
-static int sandbox_chroot(uid_t uid)
-{
- char *sandbox_root = NULL;
-
- compute_new_root(VSERVER_ROOT_BASE,&sandbox_root, uid);
- mount_proc(sandbox_root,uid);
- mount_devpts(sandbox_root);
- if (chroot(sandbox_root) < 0) {
- fprintf(stderr,"vserver: chroot error (%s): ",sandbox_root);
- perror("");
- exit(1);
- }
- if (chdir("/") < 0) {
- perror("vserver: chdir error ");
- exit(1);
- }
- return 0;
-}
-
-static struct {
- const char *option;
- int bit;
-}tbcap[]={
- // The following capabilities are normally available
- // to vservers administrator, but are place for
- // completeness
- {"CAP_CHOWN",CAP_CHOWN},
- {"CAP_DAC_OVERRIDE",CAP_DAC_OVERRIDE},
- {"CAP_DAC_READ_SEARCH",CAP_DAC_READ_SEARCH},
- {"CAP_FOWNER",CAP_FOWNER},
- {"CAP_FSETID",CAP_FSETID},
- {"CAP_KILL",CAP_KILL},
- {"CAP_SETGID",CAP_SETGID},
- {"CAP_SETUID",CAP_SETUID},
- {"CAP_SETPCAP",CAP_SETPCAP},
- {"CAP_SYS_TTY_CONFIG",CAP_SYS_TTY_CONFIG},
- {"CAP_LEASE",CAP_LEASE},
- {"CAP_SYS_CHROOT",CAP_SYS_CHROOT},
-
- // Those capabilities are not normally available
- // to vservers because they are not needed and
- // may represent a security risk
- {"CAP_LINUX_IMMUTABLE",CAP_LINUX_IMMUTABLE},
- {"CAP_NET_BIND_SERVICE",CAP_NET_BIND_SERVICE},
- {"CAP_NET_BROADCAST",CAP_NET_BROADCAST},
- {"CAP_NET_ADMIN", CAP_NET_ADMIN},
- {"CAP_NET_RAW", CAP_NET_RAW},
- {"CAP_IPC_LOCK", CAP_IPC_LOCK},
- {"CAP_IPC_OWNER", CAP_IPC_OWNER},
- {"CAP_SYS_MODULE",CAP_SYS_MODULE},
- {"CAP_SYS_RAWIO", CAP_SYS_RAWIO},
- {"CAP_SYS_PACCT", CAP_SYS_PACCT},
- {"CAP_SYS_ADMIN", CAP_SYS_ADMIN},
- {"CAP_SYS_BOOT", CAP_SYS_BOOT},
- {"CAP_SYS_NICE", CAP_SYS_NICE},
- {"CAP_SYS_RESOURCE",CAP_SYS_RESOURCE},
- {"CAP_SYS_TIME", CAP_SYS_TIME},
- {"CAP_MKNOD", CAP_MKNOD},
-#ifdef CAP_QUOTACTL
- {"CAP_QUOTACTL", CAP_QUOTACTL},
-#endif
- {NULL,0}
-};
-
-#define VSERVERCONF "/etc/vservers/"
-static unsigned get_remove_cap(char *name) {
- FILE *fb;
- unsigned remove_cap;
-
- char *vserverconf;
- int vserverconflen;
-
- remove_cap = /* NOTE: keep in sync with chcontext.c */
- (1<<CAP_LINUX_IMMUTABLE)|
- (1<<CAP_NET_BROADCAST)|
- (1<<CAP_NET_ADMIN)|
- (1<<CAP_NET_RAW)|
- (1<<CAP_IPC_LOCK)|
- (1<<CAP_IPC_OWNER)|
- (1<<CAP_SYS_MODULE)|
- (1<<CAP_SYS_RAWIO)|
- (1<<CAP_SYS_PACCT)|
- (1<<CAP_SYS_ADMIN)|
- (1<<CAP_SYS_BOOT)|
- (1<<CAP_SYS_NICE)|
- (1<<CAP_SYS_RESOURCE)|
- (1<<CAP_SYS_TIME)|
- (1<<CAP_MKNOD)|
-#ifdef CAP_QUOTACTL
- (1<<CAP_QUOTACTL)|
-#endif
-#ifdef CAP_CONTEXT
- (1<<CAP_CONTEXT)|
-#endif
- 0
- ;
-
- /*
- * find out which capabilities to put back in by reading the conf file
- */
-
- /* construct the pathname to the conf file */
- vserverconflen = strlen(VSERVERCONF) + strlen(name) + strlen(".conf") + NULLBYTE_SIZE;
- vserverconf = (char *)malloc(vserverconflen);
- sprintf(vserverconf, "%s%s.conf", VSERVERCONF, name);
-
- fprintf(stderr,"opening file %s\n",vserverconf);
- /* open the conf file for reading */
- fb = fopen(vserverconf,"r");
- if (fb != NULL) {
- int index;
- unsigned cap;
- ssize_t bufsize;
- size_t len = 0;
- char *buffer = NULL;
-
- /* the conf file file exist */
- while((bufsize = getline(&buffer,&len,fb))>0) {
- index = 0;
-
- /* walk past leading spaces */
- while(isspace((int)buffer[index]) && (index < bufsize)) index++;
-
- /* ignore if it's a comment */
- if ((buffer[index] == '#') || (index >= bufsize)) continue;
-
- /* check if it is the S_CAPS */
- if (strstr(buffer,"S_CAPS")!=NULL) {
- int j;
- cap = 0;
-
- fprintf(stderr,"Found S_CAPS\n");
- for (j=0; tbcap[j].option != NULL; j++){
- if (strstr(buffer,tbcap[j].option)!=NULL){
- fprintf(stderr,"%s\n",tbcap[j].option);
- cap |= (1<<tbcap[j].bit);
- }
- }
- remove_cap &= ~cap;
- break;
- }
- }
- /* close the conf file */
- fclose(fb);
- } else {
- fprintf(stderr,"failed to open %s\n",vserverconf);
- }
- return remove_cap;
-}
-
-static int sandbox_processes(uid_t uid, unsigned remove_cap)
-{
- int context;
- int flags;
-
- /* Unique context */
- context = uid;
-
- flags = 0;
- flags |= 1; /* VX_INFO_LOCK -- cannot request a new vx_id */
- /* flags |= 4; VX_INFO_NPROC -- limit number of procs in a context */
-
- if (vc_new_s_context(context,remove_cap,flags) < 0) {
- perror("vserver: new_s_context error ");
- exit(1);
- }
- return 0;
-}
-
-
-void runas_slice_user(char *username)
-{
- struct passwd *pwd;
- char *home_env, *logname_env, *mail_env, *shell_env, *user_env;
- int home_len, logname_len, mail_len, shell_len, user_len;
- static char *envp[10];
-
- if ((pwd = getpwnam(username)) == NULL) {
- perror("vserver: getpwnam error ");
- exit(1);
- }
-
- if (setgid(pwd->pw_gid) < 0) {
- perror("vserver: setgid error ");
- exit(1);
- }
-
- if (setuid(pwd->pw_uid) < 0) {
- perror("vserver: setuid error ");
- exit(1);
- }
-
- if (chdir(pwd->pw_dir) < 0) {
- perror("vserver: chdir error ");
- exit(1);
- }
-
- home_len = strlen("HOME=") + strlen(pwd->pw_dir) + NULLBYTE_SIZE;
- logname_len = strlen("LOGNAME=") + strlen(username) + NULLBYTE_SIZE;
- mail_len = strlen("MAIL=/var/spool/mail/") + strlen(username)
- + NULLBYTE_SIZE;
- shell_len = strlen("SHELL=") + strlen(pwd->pw_shell) + NULLBYTE_SIZE;
- user_len = strlen("USER=") + strlen(username) + NULLBYTE_SIZE;
-
- home_env = (char *)malloc(home_len);
- logname_env = (char *)malloc(logname_len);
- mail_env = (char *)malloc(mail_len);
- shell_env = (char *)malloc(shell_len);
- user_env = (char *)malloc(user_len);
-
- if ((home_env == NULL) ||
- (logname_env == NULL) ||
- (mail_env == NULL) ||
- (shell_env == NULL) ||
- (user_env == NULL)) {
- perror("vserver: malloc error ");
- exit(1);
- }
-
- sprintf(home_env, "HOME=%s", pwd->pw_dir);
- sprintf(logname_env, "LOGNAME=%s", username);
- sprintf(mail_env, "MAIL=/var/spool/mail/%s", username);
- sprintf(shell_env, "SHELL=%s", pwd->pw_shell);
- sprintf(user_env, "USER=%s", username);
-
- home_env[home_len - 1] = '\0';
- logname_env[logname_len - 1] = '\0';
- mail_env[mail_len - 1] = '\0';
- shell_env[shell_len - 1] = '\0';
- user_env[user_len - 1] = '\0';
-
- envp[0] = home_env;
- envp[1] = logname_env;
- envp[2] = mail_env;
- envp[3] = shell_env;
- envp[4] = user_env;
- envp[5] = 0;
-
- if ((putenv(home_env) < 0) ||
- (putenv(logname_env) < 0) ||
- (putenv(mail_env) < 0) ||
- (putenv(shell_env) < 0) ||
- (putenv(user_env) < 0)) {
- perror("vserver: putenv error ");
- exit(1);
- }
-}
-
-
-
-void slice_enter(char *context)
-{
- struct passwd *pwd;
- unsigned remove_cap;
- uid_t uid;
-
- if ((pwd = getpwnam(context)) == NULL) {
- fprintf(stderr,"vserver: getpwname(%s) failed",context);
- exit(2);
- }
-
- context = (char*)malloc(strlen(pwd->pw_name)+NULLBYTE_SIZE);
- if (!context) {
- perror("vserver: malloc failed");
- exit(2);
- }
- strcpy(context,pwd->pw_name);
-
- if (setuidgid_root() < 0) { /* For chroot, new_s_context */
- fprintf(stderr,"vserver: Could not setuid/setguid to root:root\n");
- exit(2);
- }
-
- remove_cap = get_remove_cap(context);
-
- uid = pwd->pw_uid;
- if (sandbox_chroot(uid) < 0) {
- fprintf(stderr, "vserver: Could not chroot to vserver root\n");
- exit(2);
- }
-
- if (sandbox_processes(uid, remove_cap) < 0) {
- fprintf(stderr, "vserver: Could not sandbox processes in vserver\n");
- exit(2);
- }
-}
git://git.onelab.eu / util-vserver.git / commitdiff