[monkey-bubble: 61/753] check for setfsgid() (used by new gnome-score) No more gnome-score-helper.

[Sven Herzberg <herzi src gnome org>]

commit 38c687667594efd5faa7ae52104ff51b38718d55
Author: EST 1998 Nathan Bryant <bryant cs usm maine edu>
Date:   Tue Feb 3 03:52:59 1998 +0000

    check for setfsgid() (used by new gnome-score) No more gnome-score-helper.
    
    Mon Feb  2 22:08:05 EST 1998 Nathan Bryant <bryant cs usm maine edu>
            * configure.in: check for setfsgid() (used by new gnome-score)
            * libgnome/gnome-score.c: No more gnome-score-helper. Games must now
              be setgid games and call gnome_score_init("name of game here") before
              anything else in main(). (Including gtk_init/gnome_init.)
            * libgnome/gnome-score-helper.c: removed
            * libgnome/Makefile.am: updated for no gnome-score-helper
            * programs/gnomine/gnomine.c: added gnome_score_init

 libgnome/gnome-score.c |  437 ++++++++++++++++++++++++++++++++++++++----------
 1 files changed, 348 insertions(+), 89 deletions(-)
---
diff --git a/libgnome/gnome-score.c b/libgnome/gnome-score.c
index 9cf6127..b277496 100644
--- a/libgnome/gnome-score.c
+++ b/libgnome/gnome-score.c
@@ -1,109 +1,368 @@
+/*
+ * gnome-score.c
+ * originally by Elliot Lee, subsequently bashed around by Nathan Bryant
+ */
+
 #include <unistd.h>
 #include <sys/types.h>
 #include <sys/wait.h>
 #include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
 #include <glib.h>
+#include <pwd.h>
+#include <ctype.h>
 
 #include "gnome-defs.h"
 #include "gnome-score.h"
+#include "gnome-util.h"
+
+#ifndef NSCORES
+#define NSCORES 10
+#endif
+
+#define SCORE_PATH GNOMELOCALSTATEDIR "/games"
+
+struct command
+{
+   gfloat score;
+   int level;			/* length of level arg to gnome_score_log
+				 * including null term */
+   gboolean ordering;
+};
+
+struct ascore_t
+{
+   gchar *username;
+   time_t scoretime;
+   gfloat score;
+};
+
+static int outfd = -1, infd = -1;
+static const gchar *defgamename;
+
+/********************** internal functions ***********************************/
+
+static gchar *
+gnome_get_score_file_name (const gchar * progname, const gchar * level)
+{
+   if (level)
+     return g_copy_strings (SCORE_PATH "/",
+			    progname, ".", level, ".scores", NULL);
+   else
+     return g_copy_strings (SCORE_PATH "/",
+			    progname, ".scores", NULL);
+}
+
+static void
+print_ascore (struct ascore_t *ascore, FILE * outfile)
+{
+   fprintf (outfile, "%f %ld %s\n", ascore->score,
+	    (long int) ascore->scoretime, ascore->username);
+}
+
+static void
+free_ascore(struct ascore_t *data)
+{
+   g_free(data->username);
+   g_free(data);
+}
+
+static gint
+log_score (const gchar * progname, const gchar * level, gchar * username,
+	   gfloat score, int ordering)
+{
+   FILE *infile;
+   FILE *outfile;
+   gchar buf[512], *buf2;
+   GList *scores = NULL, *anode;
+   gchar *name, *game_score_file;
+   gfloat ascore;
+   time_t atime;
+   struct ascore_t *anitem, *curscore;
+   int i;
+   gint retval = 1;
+   gint pos;
+   
+   game_score_file = gnome_get_score_file_name (progname, level);
+   
+   infile = fopen (game_score_file, "r");
+   if (infile)
+     {
+	while (fgets (buf, sizeof (buf), infile))
+	  {
+	     i = strlen (buf) - 1;	/* Chomp */
+	     while (isspace (buf[i]))
+	       buf[i--] = '\0';
+	     
+	     buf2 = strtok (buf, " ");
+	     ascore = atof (buf2);
+	     buf2 = strtok (NULL, " ");
+	     (long int) atime = atoi (buf2);
+	     buf2 = strtok (NULL, "\n");
+	     name = strdup (buf2);
+	     
+	     anitem = g_malloc (sizeof (struct ascore_t));
+	     anitem->score = ascore;
+	     anitem->username = name;
+	     anitem->scoretime = atime;
+	     scores = g_list_append (scores, (gpointer) anitem);
+	  }
+	fclose (infile);
+     }
+   anitem = g_malloc (sizeof (struct ascore_t));
+   anitem->score = score;
+   anitem->username = g_strdup(username);
+   anitem->scoretime = time (NULL);
+   
+   for (pos = 0, anode = scores;
+	pos < NSCORES && anode;
+	pos++, anode = anode->next)
+     {
+	curscore = anode->data;
+	if (ordering)
+	  {
+	     if (curscore->score < anitem->score)
+	       break;
+	  }
+	else
+	  {
+	     if (curscore->score > anitem->score)
+	       break;
+	  }
+     }
+   
+   if (pos < NSCORES)
+     {
+	scores = g_list_insert (scores, anitem, pos);
+	if ((anode = g_list_nth (scores, NSCORES)))
+	  {
+	     free_ascore (anode->data);
+	     scores =
+	       g_list_remove_link (scores, g_list_nth (scores, NSCORES));
+	  }
+	retval = pos + 1;
+     }
+   else
+     retval = 0;
+   
+   /* we dont create the file; it must already exist */
+   truncate (game_score_file, 0);
+   outfile = fopen (game_score_file, "r+");
+   
+   if (outfile)
+     {
+	g_list_foreach (scores, (GFunc) print_ascore, outfile);
+	fclose (outfile);
+     }
+   else
+     perror (game_score_file);
+
+   g_free (game_score_file);
+   
+   g_list_foreach (scores, (GFunc) free_ascore, NULL);
+   g_list_free (scores);
+   
+   return retval;
+}
+
+static int
+gnome_score_child (void)
+{
+   struct command cmd;
+   gchar *level;
+   struct passwd *pwd;
+   gint retval;
+#ifdef HAVE_SETFSGID
+   gid_t gid;
+   
+   gid = getegid ();
+   setgid (getgid ());
+   setfsgid (gid);
+#endif
+   pwd = getpwuid (getuid ());
+   strtok(pwd->pw_gecos, ",");
+   while (read (STDIN_FILENO, &cmd, sizeof cmd) == sizeof cmd)
+     {
+	level = g_new (char, cmd.level);
+	if (read (STDIN_FILENO, level, cmd.level) != cmd.level)
+	  return EXIT_FAILURE;
+	if (!*level) {
+	   g_free(level);
+	   level = NULL;
+	}
+	retval = log_score (defgamename, level, pwd->pw_gecos, cmd.score,
+			    cmd.ordering);
+	if (write(STDOUT_FILENO, &retval, sizeof retval) != sizeof retval)
+	  return EXIT_FAILURE;
+	if (level)
+	  g_free(level);
+     }
+   return EXIT_SUCCESS;
+}
+
+static void 
+drop_perms (void)
+{
+   gid_t gid = getegid ();
+   
+   setregid (getgid (), getgid ());	/* on some os'es (eg linux) this
+					 * incantation will also drop the
+					 * saved gid */
+   /* see if we can set it back -- if we can, saved id wasnt dropped */
+   if (!setgid (gid))
+     {
+	g_warning ("losing saved gid implementation detected, "
+		   "get a real OS :)\n");
+	setgid (getgid ());
+     }
+}
 
-#define GNOME_SCORE_C 1
-#include "gnome-score-helper.c"
-#undef GNOME_SCORE_C
+/*********************** external functions **********************************/
+
+/*
+ * gnome_score_init()
+ * creates a child process with which we communicate through a pair of pipes,
+ * then drops privileges.
+ * this should be called as the first statement in main().
+ * returns 0 on success, drops privs and returns -1 on failure
+ */
 
 gint
-gnome_score_log(gfloat score,
-		gchar *level,
-		gboolean higher_to_lower_score_order)
+gnome_score_init (const gchar * gamename)
 {
-  int exitstatus;
-  char buf[64];
-  char buf2[64];
-
-  pid_t childpid = fork();
-
-  if(childpid == 0)
-    {
-      /* We are the child */
-      g_snprintf(buf, sizeof(buf), "%f", score);
-      g_snprintf(buf2, sizeof(buf2), "%d", higher_to_lower_score_order);
-      execlp("gnome-score-helper", "gnome-score-helper",
-	     buf, level?level:"", buf2, NULL);
-      _exit(99);
-    }
-
-  waitpid(childpid, &exitstatus, 0);
-  if(WIFEXITED(exitstatus) && (WEXITSTATUS(exitstatus) != -1) )
-    return (WEXITSTATUS(exitstatus));
-  else
-    {
-      g_warning("Scorekeeping failed\n");
-      return 0;
-    }
+   int inpipe[2], outpipe[2];
+   
+   if (!gamename)
+     gamename = "";
+   if (!(defgamename = g_strdup (gamename)) ||
+       pipe(inpipe))
+     {
+	drop_perms();
+	return -1;
+     }
+   if (pipe (outpipe))
+     {
+	close (inpipe[0]);
+	close (inpipe[1]);
+	drop_perms ();
+	return -1;
+     }
+   outfd = outpipe[1];
+   infd = inpipe[0];
+   switch (fork ())
+     {
+      case 0:
+	if (dup2 (outpipe[0], STDIN_FILENO) == -1 ||
+	    dup2 (inpipe[1], STDOUT_FILENO) == -1)
+	  exit (EXIT_FAILURE);
+	close(inpipe[0]);
+	close(inpipe[1]);
+	close(outpipe[0]);
+	close(outpipe[1]);
+	exit (gnome_score_child ());
+      case -1:
+	close (inpipe[0]);
+	close (inpipe[1]);
+	close (outpipe[0]);
+	close (outpipe[1]);
+	infd = outfd = -1;
+	drop_perms ();
+	return -1;
+     }
+   close(outpipe[0]);
+   close(inpipe[1]);
+   drop_perms ();
+   return 0;
 }
 
 gint
-gnome_score_get_notable(gchar *gamename,
-			gchar *level,
-			gchar ***names,
-			gfloat **scores,
-			time_t **scoretimes)
+gnome_score_log (gfloat score,
+		 gchar * level,
+		 gboolean higher_to_lower_score_order)
 {
-  GList *l_scores, *anode;
-  struct ascore_t *curscore;
-  gchar *realname;
-  gchar *game_score_section;
-  gint retval;
-  gint i;
-
-  g_return_val_if_fail(names != NULL, 0);
-  g_return_val_if_fail(scores != NULL, 0);
-
-  if (gamename == NULL)
-    realname = gnome_get_program_name(getpid());
-  else
-    realname = g_strdup(gamename);
-  if(!realname)
-    return -1;
-
-  game_score_section = g_copy_strings ("=" SCORE_PATH "/",
-	realname, ".scores=", "/",
-	level ? level : "Top Ten",
-	"/", NULL);
-/*  l_scores = read_scores (game_score_section); */
-  g_free(realname);
-  g_free(game_score_section);
-
-  retval = g_list_length (l_scores);
-
-  if(retval)
-  {
-  	*names = g_malloc((retval+1) * sizeof(gchar*));
-  	*scores = g_malloc((retval+1) * sizeof(gfloat));
-  	*scoretimes = g_malloc((retval+1) * sizeof(time_t));
-
-	for(i = 0, anode = l_scores;
-            i < retval && anode;
-            i++, anode = anode->next)
-        {
-                curscore = anode->data;
-		(*names)[i]      = curscore->username;
-		(*scores)[i]     = curscore->score;
-		(*scoretimes)[i] = curscore->scoretime;
-        }
-        g_list_free (l_scores);
+   struct command cmd;
+   gint retval;
+   
+   if (getgid () != getegid ())
+     {
+	g_error ("gnome_score_init must be called first thing in main()\n");
+	abort ();
+     }
+   if (infd == -1 || outfd == -1)
+     return 0;
+   
+   cmd.score = score;
+   if (!level)
+     level = "";
+   cmd.level = strlen (level) + 1;
+   cmd.ordering = higher_to_lower_score_order;
+   
+   if (write (outfd, &cmd, sizeof cmd) != sizeof cmd ||
+       write (outfd, level, cmd.level) != cmd.level ||
+       read (infd, &retval, sizeof retval) != sizeof retval)
+     {
+	close (outfd);
+	close (infd);
+	infd = outfd = -1;
+	return 0;
+     }
+   return retval;
+}
 
+gint
+gnome_score_get_notable (gchar * gamename,
+			 gchar * level,
+			 gchar *** names,
+			 gfloat ** scores,
+			 time_t ** scoretimes)
+{
+   const gchar *realname;
+   gchar buf[512], *buf2;
+   gchar *infile_name;
+   FILE *infile;
+   gint retval;
+   
+   g_return_val_if_fail (names != NULL, 0);
+   g_return_val_if_fail (scores != NULL, 0);
+   
+   if (gamename == NULL)
+     realname = defgamename;
+   else
+     realname = gamename;
+   
+   infile_name = gnome_get_score_file_name (realname, level);
+   
+   infile = fopen (infile_name, "r");
+   g_free (infile_name);
+   
+   if (infile)
+     {
+	*names = g_malloc ((NSCORES + 1) * sizeof (gchar *));
+	*scores = g_malloc ((NSCORES + 1) * sizeof (gfloat));
+	*scoretimes = g_malloc ((NSCORES + 1) * sizeof (time_t));
+	
+	for (retval = 0;
+	     fgets (buf, sizeof (buf), infile) && retval < NSCORES;
+	     retval++)
+	  {
+	     buf[strlen (buf) - 1] = 0;
+	     buf2 = strtok (buf, " ");
+	     (*scores)[retval] = atof (buf2);
+	     buf2 = strtok (NULL, " ");
+	     (*scoretimes)[retval] = atoi (buf2);
+	     buf2 = strtok (NULL, "\n");
+	     (*names)[retval] = g_strdup (buf2);
+	  }
 	(*names)[retval] = NULL;
 	(*scores)[retval] = 0.0;
-	(*scoretimes)[retval] = 0;
-  }
-  else 
-  {
-  	*names = NULL;
-  	*scores = NULL;
-  	*scoretimes = NULL;
-  	retval = 0;
-  }
-
-  return retval;
+	fclose (infile);
+     }
+   else
+     {
+	*names = NULL;
+	*scores = NULL;
+	retval = 0;
+     }
+   return retval;
 }