* 02111-1307, USA.
*/
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+#include "compat.h"
+
#include <stdio.h>
#include <stdlib.h>
-#include <unistd.h>
-#include <sys/types.h>
-#include <pwd.h>
#include <string.h>
#include <errno.h>
+#include <limits.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 <sys/resource.h>
+#include <fcntl.h>
+#include <ctype.h>
+#include <stdarg.h>
+
+//--------------------------------------------------------------------
+#include "vserver.h"
+#include "planetlab.h"
+
+#undef CONFIG_VSERVER_LEGACY
+
+/* 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) {
+ PERROR("setgid(0)");
+ return -1;
+ }
+ if (setuid(0) < 0) {
+ PERROR("setuid(0)");
+ return -1;
+ }
+ return 0;
+}
+
+static void compute_new_root(char *base, char **root, const struct passwd *pwd)
+{
+ int root_len;
+
+ root_len =
+ strlen(base) + strlen("/") +
+ strlen(pwd->pw_name) + NULLBYTE_SIZE;
+ (*root) = (char *)malloc(root_len);
+ if ((*root) == NULL) {
+ PERROR("malloc(%d)", root_len);
+ exit(1);
+ }
+
+ sprintf((*root), "%s/%s", base, pwd->pw_name);
+ (*root)[root_len - 1] = '\0';
+}
+
+static int sandbox_chroot(const struct passwd *pwd)
+{
+ char *sandbox_root = NULL;
+
+ compute_new_root(VSERVER_ROOT_BASE,&sandbox_root, pwd);
+ if (chroot(sandbox_root) < 0) {
+ PERROR("chroot(%s)", sandbox_root);
+ exit(1);
+ }
+ if (chdir("/") < 0) {
+ PERROR("chdir(/)");
+ exit(1);
+ }
+ return 0;
+}
+
+static int sandbox_processes(xid_t ctx, const char *context, const struct passwd *pwd)
+{
+#ifdef CONFIG_VSERVER_LEGACY
+ int flags;
+
+ 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 */
+
+ (void) vc_new_s_context(ctx, 0, flags);
+
+ /* use legacy dirty hack for capremove */
+ if (vc_new_s_context(VC_SAMECTX, vc_get_insecurebcaps(), flags) == VC_NOCTX) {
+ PERROR("vc_new_s_context(%u, 0x%16llx, 0x%08x)",
+ VC_SAMECTX, vc_get_insecurebcaps(), flags);
+ exit(1);
+ }
+#else
+ int ctx_is_new;
+ struct sliver_resources slr;
+ char hostname[HOST_NAME_MAX+1];
+ pl_get_limits(context,&slr);
+
+ if (gethostname(hostname, sizeof hostname) == -1)
+ {
+ PERROR("gethostname(...)");
+ exit(1);
+ }
+
+ /* check whether the slice has been suspended */
+ if (slr.vs_cpu==0)
+ {
+ fprintf(stderr, "*** %s: %s has zero cpu resources and presumably it has been disabled/suspended ***\n", hostname, context);
+ exit(0);
+ }
+
+ (void) (sandbox_chroot(pwd));
+
+ if ((ctx_is_new = pl_chcontext(ctx, ~vc_get_insecurebcaps(),&slr)) < 0)
+ {
+ PERROR("pl_chcontext(%u)", ctx);
+ exit(1);
+ }
+ if (ctx_is_new)
+ {
+ fprintf(stderr, " *** %s: %s has not been started yet, please check back later ***\n", hostname, context);
+ exit(1);
+ }
+#endif
+ return 0;
+}
+
+
+void runas_slice_user(struct passwd *pwd)
+{
+ char *username = pwd->pw_name;
+ 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 (setgid(pwd->pw_gid) < 0) {
+ PERROR("setgid(%d)", pwd->pw_gid);
+ exit(1);
+ }
+
+ if (setuid(pwd->pw_uid) < 0) {
+ PERROR("setuid(%d)", pwd->pw_uid);
+ exit(1);
+ }
+
+ if (chdir(pwd->pw_dir) < 0) {
+ PERROR("chdir(%s)", pwd->pw_dir);
+ 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("malloc");
+ 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(struct passwd *pwd)
+{
+ if (setuidgid_root() < 0) { /* For chroot, new_s_context */
+ fprintf(stderr, "vsh: Could not become root, check that SUID flag is set on binary\n");
+ exit(2);
+ }
+
+#ifdef CONFIG_VSERVER_LEGACY
+ (void) (sandbox_chroot(pwd));
+#endif
+
+ if (sandbox_processes((xid_t) pwd->pw_uid, pwd->pw_name, pwd) < 0) {
+ fprintf(stderr, "vsh: Could not change context to %d\n", pwd->pw_uid);
+ exit(2);
+ }
+}
+
+//--------------------------------------------------------------------
#define DEFAULT_SHELL "/bin/sh"
EXIT_ENOENT = 127
};
-extern void slice_enter(char *);
-extern void runas_slice_user(char *);
-
int main(int argc, char **argv)
{
- char *context, *username, *shell;
- struct passwd *pwd;
+ struct passwd pwdd, *result, *prechroot, *postchroot = &pwdd;
+ char *context, *username, *shell, *pwdBuffer;
+ long pwdBuffer_len;
uid_t uid;
- int index, i;
+ int index, i;
if (argv[0][0]=='-')
index = 1;
index = 0;
uid = getuid();
- if ((pwd = getpwuid(uid)) == NULL) {
- fprintf(stderr,"vsh: getpwnam error failed for %d\n",uid);
+ if ((prechroot = getpwuid(uid)) == NULL) {
+ PERROR("getpwuid(%d)", uid);
exit(1);
}
- context = (char*)strdup(pwd->pw_name);
+ context = (char*)strdup(prechroot->pw_name);
if (!context) {
- perror("vsh: strdup failed");
+ PERROR("strdup");
exit(2);
}
/* enter vserver "context" */
- slice_enter(context);
+ slice_enter(prechroot);
- /* Now run as username in this context. Note that for PlanetLab's
- vserver configuration the context name also happens to be the
- "default" username within the vserver context.
- */
+ /* Get the /etc/passwd entry for this user, this time inside
+ * the chroot.
+ */
username = context;
- runas_slice_user(username);
- /* With the uid/gid appropriately set. Let's figure out what the
- * shell in the vserver's /etc/passwd is for the given username.
- */
- if ((pwd = getpwnam(username)) == NULL) {
- fprintf(stderr,"vsh: getpwnam error failed for %s\n",username);
+ pwdBuffer_len = sysconf(_SC_GETPW_R_SIZE_MAX);
+ if (pwdBuffer_len == -1) {
+ PERROR("sysconf(_SC_GETPW_R_SIZE_MAX");
+ exit(1);
+ }
+ pwdBuffer = (char*)malloc(pwdBuffer_len);
+ if (pwdBuffer == NULL) {
+ PERROR("malloc(%d)", pwdBuffer_len);
+ exit(1);
+ }
+
+ errno = 0;
+ if ((getpwnam_r(username,postchroot,pwdBuffer,pwdBuffer_len, &result) != 0) ||
+ (errno != 0) || result != postchroot) {
+ PERROR("getpwnam_r(%s)", username);
exit(1);
}
+ /* Now run as username in this context. Note that for PlanetLab's
+ vserver configuration the context name also happens to be the
+ "default" username within the vserver context.
+ */
+ runas_slice_user(postchroot);
+
/* Make sure pw->pw_shell is non-NULL.*/
- if (pwd->pw_shell == NULL || pwd->pw_shell[0] == '\0') {
- pwd->pw_shell = (char *) DEFAULT_SHELL;
+ if (postchroot->pw_shell == NULL || postchroot->pw_shell[0] == '\0') {
+ postchroot->pw_shell = (char *) DEFAULT_SHELL;
}
- shell = (char *)strdup(pwd->pw_shell);
+ shell = (char *)strdup(postchroot->pw_shell);
if (!shell) {
- perror("vsh: strdup failed");
+ PERROR("strdup");
exit(2);
}
char **args;
args = (char**)malloc(sizeof(char*)*(argc+2));
if (!args) {
- perror("vsh: malloc failed");
+ PERROR("malloc(%d)", sizeof(char*)*(argc+2));
+ exit(1);
}
args[0] = argv[0];
args[1] = "-l";
git://git.onelab.eu / util-vserver.git / blobdiff