#include <stdio.h>
#include <stdlib.h>
#include <string.h>
-#include <stdlib.h>
#include <errno.h>
+#include <limits.h>
#include <pwd.h>
#include <unistd.h>
#include <syscall.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 "linuxcaps.h"
#include "vserver.h"
+#include "planetlab.h"
-/* Null byte made explicit */
-#define NULLBYTE_SIZE 1
+#undef CONFIG_VSERVER_LEGACY
/* Base for all vserver roots for chroot */
#define VSERVER_ROOT_BASE "/vservers"
static int setuidgid_root()
{
if (setgid(0) < 0) {
- fprintf(stderr, "setgid error\n");
+ PERROR("setgid(0)");
return -1;
}
if (setuid(0) < 0) {
- fprintf(stderr, "setuid error\n");
+ PERROR("setuid(0)");
return -1;
}
return 0;
}
-static void compute_new_root(char *base, char **root, uid_t uid)
+static void compute_new_root(char *base, char **root, const struct passwd *pwd)
{
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 ");
+ PERROR("malloc(%d)", root_len);
exit(1);
}
(*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)
+static int sandbox_chroot(const struct passwd *pwd)
{
char *sandbox_root = NULL;
- compute_new_root(VSERVER_ROOT_BASE,&sandbox_root, uid);
- mount_proc(sandbox_root,uid);
- mount_devpts(sandbox_root);
+ compute_new_root(VSERVER_ROOT_BASE,&sandbox_root, pwd);
if (chroot(sandbox_root) < 0) {
- fprintf(stderr,"vserver: chroot error (%s): ",sandbox_root);
- perror("");
+ PERROR("chroot(%s)", sandbox_root);
exit(1);
}
if (chdir("/") < 0) {
- perror("vserver: chdir error ");
+ PERROR("chdir(/)");
exit(1);
}
return 0;
}
-#ifndef CAP_CONTEXT
-# define CAP_CONTEXT 29
-#endif
-
-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},
- {"CAP_CONTEXT", CAP_CONTEXT},
- {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)|
- (1<<CAP_CONTEXT)|
- 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);
-
- /* open the conf file for reading */
- fb = fopen(vserverconf,"r");
- if (fb != NULL) {
- unsigned cap;
- size_t index;
- size_t len;
- char buffer[1000], *p;
-
- /* the conf file file exist */
- while((p=fgets(buffer,sizeof(buffer)-1,fb))!=NULL) {
-
- /* walk past leading spaces */
- index = 0;
- len = strnlen(buffer,sizeof(buffer)-1);
- while(isspace((int)buffer[index])) {
- if (index < len) {
- index++;
- } else {
- goto out;
- }
- }
-
- if (buffer[index] == '#') continue;
-
- /* check if it is the S_CAPS */
- if ((p=strstr(&buffer[index],"S_CAPS"))!=NULL) {
- int j;
- cap = 0;
-
- /* what follows is a bunch of error
- checking to parse the S_CAPS="..."
- string */
-
- /* adjust index into buffer */
- index+= (p-&buffer[index])+strlen("S_CAPS");
-
- /* skip over whitespace */
- while(isspace((int)buffer[index])) {
- if (index < len) {
- index++;
- } else {
- /* parse error */
- goto out;
- }
- }
-
- /* expecting to see = sign */
- if (buffer[index++]!='=') {
- /* parse error */
- goto out;
- }
-
- /* skip over whitespace */
- while(isspace((int)buffer[index])) {
- if (index < len) {
- index++;
- } else {
- /* parse error */
- goto out;
- }
- }
-
- /* expecting to see the opening " */
- if (buffer[index]!='"') {
- /* parse error */
- goto out;
- }
-
- /* check to see that we are still within bounds */
- if (index < len) {
- index++;
- } else {
- /* parse error */
- goto out;
- }
-
- /* search for the closing " */
- if((p=strstr(&buffer[index],"\""))==NULL) {
- /* parse error */
- goto out;
- }
-
- /* ok... we should now have a bunch of
- CAP keys words within the quotes */
-
- for (j=0; tbcap[j].option != NULL; j++){
- if ((p=strstr(buffer,tbcap[j].option))!=NULL){
- len = strlen(tbcap[j].option);
- if (((isspace(*(p-1))) || (*(p-1)=='"')) &&
- ((isspace(*(p+len))) || (*(p+len)=='"'))) {
- cap |= (1<<tbcap[j].bit);
- } else {
- /* parse error */
- goto out;
- }
- }
- }
- remove_cap &= ~cap;
- break;
- }
- }
- out:
- /* close the conf file */
- fclose(fb);
- }
- return remove_cap;
-}
-
-static int sandbox_processes(uid_t uid, unsigned remove_cap)
+static int sandbox_processes(xid_t ctx, const char *context, const struct passwd *pwd)
{
- int context;
- int flags;
-
- /* Unique context */
- context = uid;
+#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 */
- if (vc_new_s_context(context,remove_cap,flags) < 0) {
- perror("vserver: new_s_context error ");
+ (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(char *username)
+void runas_slice_user(struct passwd *pwd)
{
- 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 ((pwd = getpwnam(username)) == NULL) {
- perror("vserver: getpwnam error ");
- exit(1);
- }
-
if (setgid(pwd->pw_gid) < 0) {
- perror("vserver: setgid error ");
+ PERROR("setgid(%d)", pwd->pw_gid);
exit(1);
}
if (setuid(pwd->pw_uid) < 0) {
- perror("vserver: setuid error ");
+ PERROR("setuid(%d)", pwd->pw_uid);
exit(1);
}
if (chdir(pwd->pw_dir) < 0) {
- perror("vserver: chdir error ");
+ PERROR("chdir(%s)", pwd->pw_dir);
exit(1);
}
(mail_env == NULL) ||
(shell_env == NULL) ||
(user_env == NULL)) {
- perror("vserver: malloc error ");
+ PERROR("malloc");
exit(1);
}
(putenv(mail_env) < 0) ||
(putenv(shell_env) < 0) ||
(putenv(user_env) < 0)) {
- perror("vserver: putenv error ");
+ PERROR("vserver: putenv error ");
exit(1);
}
}
-
-
-void slice_enter(char *context)
+void slice_enter(struct passwd *pwd)
{
- 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");
+ fprintf(stderr, "vsh: Could not become root, check that SUID flag is set on binary\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);
- }
+#ifdef CONFIG_VSERVER_LEGACY
+ (void) (sandbox_chroot(pwd));
+#endif
- if (sandbox_processes(uid, remove_cap) < 0) {
- fprintf(stderr, "vserver: Could not sandbox processes in vserver\n");
+ 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);
}
}
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