X-Git-Url: https://git.distorted.org.uk/~mdw/become/blobdiff_plain/9df0c75da76d81285c5fca90bb8d538c68b38119..c758e6541ca05409b178dd9629e9337494c49890:/src/become.c

diff --git a/src/become.c b/src/become.c
index d94e3c2..79ec7ae 100644
--- a/src/become.c
+++ b/src/become.c
@@ -1,10 +1,10 @@
 /* -*-c-*-
  *
- * $Id: become.c,v 1.10 1997/09/17 10:14:10 mdw Exp $
+ * $Id: become.c,v 1.14 1998/01/12 16:45:39 mdw Exp $
  *
  * Main code for `become'
  *
- * (c) 1997 EBI
+ * (c) 1998 EBI
  */
 
 /*----- Licensing notice --------------------------------------------------*
@@ -29,7 +29,25 @@
 /*----- Revision history --------------------------------------------------*
  *
  * $Log: become.c,v $
- * Revision 1.10  1997/09/17 10:14:10  mdw
+ * Revision 1.14  1998/01/12 16:45:39  mdw
+ * Fix copyright date.
+ *
+ * Revision 1.13  1997/09/26 09:14:57  mdw
+ * Merged blowfish branch into trunk.
+ *
+ * Revision 1.12  1997/09/25 16:04:48  mdw
+ * Change directory after becoming someone else, instead of before.  This
+ * avoids problems with root-squashed NFS mounts.
+ *
+ * Revision 1.11.2.1  1997/09/26 09:07:58  mdw
+ * Use the Blowfish encryption algorithm instead of IDEA.  This is partly
+ * because I prefer Blowfish (without any particularly strong evidence) but
+ * mainly because IDEA is patented and Blowfish isn't.
+ *
+ * Revision 1.11  1997/09/24  09:48:45  mdw
+ * Fix (scary) overrun bug in group allocation stuff.
+ *
+ * Revision 1.10  1997/09/17  10:14:10  mdw
  * Fix a typo.  Support service names in `--port' option.
  *
  * Revision 1.9  1997/09/10 10:28:05  mdw
@@ -304,8 +322,8 @@ static int bc__addGroups(gid_t *g, int *png, const gid_t *a, int na)
 
     /* --- See if there's room for more --- */
 
-    if (ng > NGROUPS_MAX) {
-      moan("too many groups (system limit exceeded -- some have been lost");
+    if (ng >= NGROUPS_MAX) {
+      moan("too many groups (system limit exceeded) -- some have been lost");
       *png = ng;
       return (-1);
     }
@@ -468,7 +486,7 @@ int main(int argc, char *argv[])
   enum {
     f_daemon = 1,			/* Start up in daemon mode */
     f_duff = 2,				/* Fault in arguments */
-    f_login = 4,			/* Execute as a login shell */
+    f_shell = 4,			/* Run a default shell */
     f_dummy = 8,			/* Don't actually do anything */
     f_setuid = 16,			/* We're running setuid */
     f_havegroup = 32			/* Set a default group */
@@ -1043,45 +1061,48 @@ done_options:
     binary = todo[0];
   }
 
-  else switch (style) {
+  else {
+    flags |= f_shell;
 
-    /* --- An unadorned becoming requires little work --- */
+    switch (style) {
 
-    case l_preserve:
-      shell[0] = getenv("SHELL");
-      if (!shell[0])
-	shell[0] = from_pw->pw_shell;
-      shell[1] = 0;
-      todo = shell;
-      binary = todo[0];
-      break;
+      /* --- An unadorned becoming requires little work --- */
 
-    /* --- An su-like login needs slightly less effort --- */
+      case l_preserve:
+	shell[0] = getenv("SHELL");
+	if (!shell[0])
+	  shell[0] = from_pw->pw_shell;
+	shell[1] = 0;
+	todo = shell;
+	binary = todo[0];
+	break;
 
-    case l_setuser:
-      shell[0] = to_pw->pw_shell;
-      shell[1] = 0;
-      todo = shell;
-      binary = todo[0];
-      break;
+      /* --- An su-like login needs slightly less effort --- */
 
-    /* --- A login request needs a little bit of work --- */
-
-    case l_login: {
-      const char *p = strrchr(to_pw->pw_shell, '/');
-
-      if (p)
-	p++;
-      else
-	p = to_pw->pw_shell;
-      shell[0] = xmalloc(strlen(p) + 2);
-      shell[0][0] = '-';
-      strcpy(shell[0] + 1, p);
-      shell[1] = 0;
-      todo = shell;
-      binary = to_pw->pw_shell;
-      chdir(to_pw->pw_dir);
-    } break;
+      case l_setuser:
+	shell[0] = to_pw->pw_shell;
+	shell[1] = 0;
+	todo = shell;
+	binary = todo[0];
+	break;
+
+      /* --- A login request needs a little bit of work --- */
+
+      case l_login: {
+	const char *p = strrchr(to_pw->pw_shell, '/');
+
+	if (p)
+	  p++;
+	else
+	  p = to_pw->pw_shell;
+	shell[0] = xmalloc(strlen(p) + 2);
+	shell[0][0] = '-';
+	strcpy(shell[0] + 1, p);
+	shell[1] = 0;
+	todo = shell;
+	binary = to_pw->pw_shell;
+      } break;
+    }
   }
 
   /* --- Mangle the environment --- *
@@ -1420,7 +1441,7 @@ done_options:
 
   if (rq.from == rq.to) {
     moan("you already are `%s'!", to_pw->pw_name);
-    if (!cmd && todo == shell) {
+    if (flags & f_shell) {
       moan("(to prevent confusion, I'm not spawning a shell)");
       exit(0);
     }
@@ -1455,6 +1476,13 @@ done_options:
   if (setuid(rq.to) < 0)
     die("couldn't set uid: %s", strerror(errno));
 
+  /* --- If this was a login, change current directory --- */
+
+  if (flags & f_shell && style == l_login && chdir(to_pw->pw_dir) < 0) {
+    moan("couldn't change directory to `%s': %s",
+	 to_pw->pw_dir, strerror(errno));
+  }
+
   /* --- Finally, call the program --- */
 
   fflush(0);