cpuguaranteed conditional in the code was flipped.
[util-vserver.git] / src / vsh.c
index 8290c8e..c8f3417 100644 (file)
--- a/src/vsh.c
+++ b/src/vsh.c
  * 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 <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 <sys/resource.h>
+#include <fcntl.h>
+#include <ctype.h>
+#include <stdarg.h>
+
+//--------------------------------------------------------------------
+#include "vserver.h"
+
+#undef CONFIG_VSERVER_LEGACY
+
+/* Null byte made explicit */
+#define NULLBYTE_SIZE                    1
+
+/* Base for all vserver roots for chroot */
+#define VSERVER_ROOT_BASE       "/vservers"
+
+static int
+_PERROR(const char *format, char *file, int line, int _errno, ...)
+{
+       va_list ap;
+
+       va_start(ap, _errno);
+       fprintf(stderr, "%s:%d: ", file, line);
+       vfprintf(stderr, format, ap);
+       if (_errno)
+               fprintf(stderr, ": %s (%d)", strerror(_errno), _errno);
+       fputs("\n", stderr);
+       fflush(stderr);
+
+       return _errno;
+}
+
+#define PERROR(format, args...) _PERROR(format, __FILE__, __LINE__, errno, ## args)
+
+/* 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, uid_t uid)
+{
+       int             root_len;
+       struct passwd   *pwd;
+
+       if ((pwd = getpwuid(uid)) == NULL) {
+               PERROR("getpwuid(%d)", uid);
+               exit(1);
+       }
+
+       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';
+}
+
+/* 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("malloc(%d)", len);
+               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)
+{
+       char        *source = "/proc";
+       char        *target;
+       int         len;
+
+       len = strlen(sandbox_root) + strlen("/") + strlen("proc") + NULLBYTE_SIZE;
+       if ((target = (char *)malloc(len)) == NULL) {
+               PERROR("malloc(%d)", len);
+               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("malloc(%d)", len);
+               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);
+       mount_devpts(sandbox_root);
+       if (chroot(sandbox_root) < 0) {
+               PERROR("chroot(%s)", sandbox_root);
+               exit(1);
+       }
+       if (chdir("/") < 0) {
+               PERROR("chdir(/)");
+               exit(1);
+       }
+       return 0;
+}
+
+#define WHITESPACE(buffer,index,len)     \
+  while(isspace((int)buffer[index])) \
+       if (index < len) index++; else goto out;
+
+struct resources {
+       char *name;
+       unsigned long long *limit;
+};
+
+#define VSERVERCONF "/etc/vservers/"
+static void get_limits(char *context, struct resources *list){
+       FILE *fb;
+       size_t len = strlen(VSERVERCONF) + strlen(context) + strlen(".conf") + NULLBYTE_SIZE;
+       char *conf = (char *)malloc(len);       
+       struct resources *r;
+
+       sprintf(conf, "%s%s.conf", VSERVERCONF, context);
+
+       /* open the conf file for reading */
+       fb = fopen(conf,"r");
+       if (fb != NULL) {
+               size_t index;
+               char *buffer = malloc(1000);
+               char *p;
+
+               /* the conf file exist */ 
+               while((p=fgets(buffer,1000-1,fb))!=NULL) {
+                       index = 0;
+                       len = strnlen(buffer,1000);
+                       WHITESPACE(buffer,index,len);
+                       if (buffer[index] == '#') 
+                               continue;
+
+                       for (r=list; r->name; r++)
+                               if ((p=strstr(&buffer[index],r->name))!=NULL) {
+                                       /* adjust index into buffer */
+                                       index+= (p-&buffer[index])+strlen(r->name);
+
+                                       /* skip over whitespace */
+                                       WHITESPACE(buffer,index,len);
+
+                                       /* expecting to see = sign */
+                                       if (buffer[index++]!='=') goto out;
+
+                                       /* skip over whitespace */
+                                       WHITESPACE(buffer,index,len);
+
+                                       /* expecting to see a digit for number */
+                                       if (!isdigit((int)buffer[index])) goto out;
+
+                                       *r->limit = atoi(&buffer[index]);
+                                       break;
+                               }
+               }
+       out:
+               free(buffer);
+       } else {
+               fprintf(stderr,"cannot open %s\n",conf);
+       }
+       free(conf);
+}
+
+
+static int sandbox_processes(xid_t xid, char *context)
+{
+#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(xid, 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%16ullx, 0x%08x)",
+                      VC_SAMECTX, vc_get_insecurebcaps(), flags);
+               exit(1);
+       }
+#else
+       struct vc_rlimit limits;
+       struct vc_ctx_caps caps;
+       struct vc_ctx_flags flags;
+
+       xid_t ctx;
+       unsigned long long cpu = VC_LIM_KEEP;
+       unsigned long long mem = VC_LIM_KEEP;
+       unsigned long long task = VC_LIM_KEEP;
+       unsigned long long cpuguaranteed = 0;
+       struct resources list[] = 
+               {{"MEMLIMIT", &mem},
+                {"CPULIMIT", &cpu},
+                {"CPUGUARANTEED", &cpuguaranteed},
+                {"TASKLIMIT", &task},
+                {0,0}};
+
+       get_limits(context,list);
+       (void) (sandbox_chroot(xid));
+
+       caps.ccaps = ~vc_get_insecureccaps();
+       caps.cmask = ~0ull;
+       caps.bcaps = ~vc_get_insecurebcaps();
+       caps.bmask = ~0ull;
+
+       flags.flagword = VC_VXF_INFO_LOCK;
+       flags.mask = VC_VXF_STATE_SETUP | VC_VXF_INFO_LOCK;
+
+       ctx = vc_ctx_create(xid);
+       if (ctx == VC_NOCTX && errno != EEXIST) {
+               PERROR("vc_ctx_create(%d)", xid);
+               exit(1);
+       }
+
+       /* CPU    */
+       if (cpu != VC_LIM_KEEP) {
+               struct vc_set_sched sched = {
+                       .set_mask = 0
+               };
+
+               /* Need to distinguish between guarantee (hard) and
+                * best effort (share) from the vserver
+                * configuration.
+                */
+#define VC_VXF_SCHED_SHARE       0x00000800ull
+               flags.flagword |= VC_VXF_SCHED_HARD;
+               flags.mask |= VC_VXF_SCHED_HARD;
+               if (cpuguaranteed==0) {
+                       flags.flagword |= VC_VXF_SCHED_SHARE;
+                       flags.mask |= VC_VXF_SCHED_SHARE;
+               }
+
+               /* CPULIMIT value from /etc/vservers/xyz.conf */
+               sched.fill_rate = cpu;
+               sched.set_mask |= VC_VXSM_FILL_RATE;
+
+               sched.interval  = 1000; /* Andy's default value */
+               sched.set_mask |= VC_VXSM_INTERVAL;
+
+               /* set base token value for new contexts */
+               if (ctx != VC_NOCTX) {
+                       sched.tokens = 100; /* Andy's default value */
+                       sched.set_mask |= VC_VXSM_TOKENS;
+               }
+
+               sched.tokens_min = 50; /* Andy's default value */
+               sched.tokens_max = 100; /* Andy's default value */
+               sched.set_mask |= VC_VXSM_TOKENS_MIN;
+               sched.set_mask |= VC_VXSM_TOKENS_MAX;
+
+               if (vc_set_sched(xid, &sched)==-1) {
+                       PERROR("vc_set_sched()");
+                       exit(1);
+               }
+       }
+
+       /* MEM    */
+       limits.min  = VC_LIM_KEEP;
+       limits.soft = VC_LIM_KEEP;
+       limits.hard = mem;
+       if (vc_set_rlimit(xid, RLIMIT_RSS, &limits)) {
+               PERROR("vc_set_rlimit(%d, %d, %d/%d/%d)",
+                      xid, RLIMIT_RSS, limits.min, limits.soft, limits.hard);
+               exit(1);
+       }
+       
+       /* TASK   */
+       limits.min  = VC_LIM_KEEP;
+       limits.soft = VC_LIM_KEEP;
+       limits.hard = task;
+       if (vc_set_rlimit(xid, RLIMIT_NPROC, &limits)) {
+               PERROR("vc_set_rlimit(%d, %d, %d/%d/%d)",
+                      xid, RLIMIT_NPROC, limits.min, limits.soft, limits.hard);
+               exit(1);
+       }
+       
+       if (vc_set_ccaps(xid, &caps) == -1) {
+               PERROR("vc_set_ccaps(%d, 0x%16ullx/0x%16ullx, 0x%16ullx/0x%16ullx)",
+                      xid, caps.ccaps, caps.cmask, caps.bcaps, caps.bmask);
+               exit(1);
+       }
+
+       if (vc_set_cflags(xid, &flags) == -1) {
+               PERROR("vc_set_cflags(%d, 0x%16llx/0x%16llx)",
+                      xid, flags.flagword, flags.mask);
+               exit(1);
+       }
+
+       /* context already exists, migrate to it */
+       if (ctx == VC_NOCTX && vc_ctx_migrate(xid) == -1) {
+               PERROR("vc_ctx_migrate(%d)", xid);
+               exit(1);
+       }
+#endif
+       return 0;
+}
+
+
+void runas_slice_user(char *username)
+{
+       struct passwd pwdd, *pwd = &pwdd, *result;
+       char          *pwdBuffer;
+       char          *home_env, *logname_env, *mail_env, *shell_env, *user_env;
+       int           home_len, logname_len, mail_len, shell_len, user_len;
+       long          pwdBuffer_len;
+       static char   *envp[10];
+
+
+       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,pwd,pwdBuffer,pwdBuffer_len, &result) != 0) || (errno != 0)) {
+               PERROR("getpwnam_r(%s)", username);
+               exit(1);
+       }
+
+       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(char *context)
+{
+       struct passwd pwdd, *pwd = &pwdd, *result;
+       char          *pwdBuffer;
+       long          pwdBuffer_len;
+       uid_t uid;
+
+       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(context,pwd,pwdBuffer,pwdBuffer_len, &result) != 0) || (errno != 0)) {
+               PERROR("getpwnam_r(%s)", context);
+               exit(2);
+       }
+       uid = pwd->pw_uid;
+
+       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(uid));
+#endif
+
+       if (sandbox_processes((xid_t) uid, context) < 0) {
+               fprintf(stderr, "vsh: Could not change context to %d\n", uid);
+               exit(2);
+       }
+}
+
+//--------------------------------------------------------------------
 
 #define DEFAULT_SHELL "/bin/sh"
 
@@ -37,33 +544,28 @@ enum
   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, *pwd = &pwdd, *result;
+    char            *context, *username, *shell, *pwdBuffer;
+    long            pwdBuffer_len;
     uid_t           uid;
-    int index, i;
+    int             index, i;
 
     if (argv[0][0]=='-') 
       index = 1;
     else
       index = 0;
 
-    if ((uid = getuid()) < 0) {
-      perror("vsh: getuid error ");
-      exit(1);
-    }
+    uid = getuid();
     if ((pwd = getpwuid(uid)) == NULL) {
-      fprintf(stderr,"vsh: getpwnam error failed for %d\n",uid); 
+      PERROR("getpwuid(%d)", uid);
       exit(1);
     }
 
     context = (char*)strdup(pwd->pw_name);
     if (!context) {
-      perror("vsh: strdup failed");
+      PERROR("strdup");
       exit(2);
     }
 
@@ -80,8 +582,21 @@ int main(int argc, char **argv)
     /* 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,pwd,pwdBuffer,pwdBuffer_len, &result) != 0) || (errno != 0)) {
+        PERROR("getpwnam_r(%s)", username);
         exit(1);
     }
 
@@ -92,7 +607,7 @@ int main(int argc, char **argv)
 
     shell = (char *)strdup(pwd->pw_shell);
     if (!shell) {
-      perror("vsh: strdup failed");
+      PERROR("strdup");
       exit(2);
     }
 
@@ -104,7 +619,8 @@ int main(int argc, char **argv)
       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";