diff -Naur --exclude '*.swp' bsd-games-2.17/tetris/scores.c bsd-games-2.17.new/tetris/scores.c
--- bsd-games-2.17/tetris/scores.c 2006-04-22 20:46:56.000000000 -0700
+++ bsd-games-2.17.new/tetris/scores.c 2006-04-22 22:02:45.000000000 -0700
@@ -41,6 +41,7 @@
*
* Major whacks since then.
*/
+#define _GNU_SOURCE /* this must be done before the first include of unistd.h */
#include <err.h>
#include <errno.h>
#include <fcntl.h>
@@ -77,85 +78,88 @@
static int checkscores(struct highscore *, int);
static int cmpscores(const void *, const void *);
-static void getscores(FILE **);
+static void getscores(FILE *);
static void printem(int, int, struct highscore *, int, const char *);
static char *thisuser(void);
/*
- * Read the score file. Can be called from savescore (before showscores)
- * or showscores (if savescore will not be called). If the given pointer
- * is not NULL, sets *fpp to an open file pointer that corresponds to a
- * read/write score file that is locked with LOCK_EX. Otherwise, the
- * file is locked with LOCK_SH for the read and closed before return.
- *
- * Note, we assume closing the stdio file releases the lock.
+ * Read the score file from a previously opened file pointer. If the file
+ * pointer is null, then read the scoreboard from a known location. Otherwise,
+ * the FILE pointer is rewound, read, and left open to be read again later.
*/
static void
-getscores(fpp)
- FILE **fpp;
+getscores(fp)
+ FILE *fp;
{
- int sd, mint, lck;
- mode_t mask;
- const char *mstr, *human;
- FILE *sf;
-
- if (fpp != NULL) {
- mint = O_RDWR | O_CREAT;
- mstr = "r+";
- human = "read/write";
- lck = LOCK_EX;
- } else {
- mint = O_RDONLY;
- mstr = "r";
- human = "reading";
- lck = LOCK_SH;
- }
- setegid(egid);
- mask = umask(S_IWOTH);
- sd = open(_PATH_SCOREFILE, mint, 0666);
- (void)umask(mask);
- if (sd < 0) {
- if (fpp == NULL) {
- nscores = 0;
- setegid(gid);
- return;
- }
- err(1, "cannot open %s for %s", _PATH_SCOREFILE, human);
- }
- if ((sf = fdopen(sd, mstr)) == NULL) {
- err(1, "cannot fdopen %s for %s", _PATH_SCOREFILE, human);
- }
- setegid(gid);
+ int sd = -1;
+ FILE *sf = fp;
- /*
- * Grab a lock.
- */
- if (flock(sd, lck))
- warn("warning: score file %s cannot be locked",
- _PATH_SCOREFILE);
+ if (sf == NULL) {
+ sd = open(_PATH_SCOREFILE, O_RDONLY, 0664);
+ if (sd < 0) {
+ nscores = 0;
+ return;
+ err(1, "cannot open %s for reading", _PATH_SCOREFILE);
+ }
+ if ((sf = fdopen(sd, "r")) == NULL) {
+ err(1, "cannot fdopen %s for reading", _PATH_SCOREFILE);
+ }
+ } else {
+ rewind(sf);
+ }
nscores = fread(scores, sizeof(scores[0]), MAXHISCORES, sf);
if (ferror(sf)) {
err(1, "error reading %s", _PATH_SCOREFILE);
}
- if (fpp)
- *fpp = sf;
- else
- (void)fclose(sf);
+ else {
+ if (fp == NULL) {
+ (void)fclose(sf);
+ }
+ }
+}
+
+/*
+ * Open the high score file and then drop setgid privileges. If running
+ * setgid, then calling this function a second time will result in a
+ * permission denied error since gid privileges will have been lost.
+ */
+void
+open_score(fd, fp)
+ int *fd;
+ FILE **fp;
+{
+ *fd = open(_PATH_SCOREFILE, O_RDWR | O_CREAT, 0664);
+ if (*fd < 0) {
+ err(1, "Could not open scoreboard file %s", _PATH_SCOREFILE);
+ } else {
+ *fp = fdopen(*fd, "r+");
+ if (*fp == NULL) {
+ err(1, "Could not open scoreboard file %s", _PATH_SCOREFILE);
+ }
+ }
+ if (setresgid(-1, getgid(), getgid()) == -1) {
+ perror("Could not drop setgid privileges. Aborting.");
+ exit(1);
+ }
}
void
-savescore(level)
+savescore(level, sf)
int level;
+ FILE *sf;
{
struct highscore *sp;
int i;
int change;
- FILE *sf;
const char *me;
- getscores(&sf);
+ if (sf == NULL) {
+ return;
+ }
+
+ getscores(sf);
gotscores = 1;
(void)time(&now);
@@ -215,14 +219,17 @@
static char *
thisuser()
{
- const char *p;
+ const char *p = (char *)NULL;
struct passwd *pw;
size_t l;
static char u[sizeof(scores[0].hs_name)];
if (u[0])
return (u);
+ /* Don't use getlogin() as it will return the wrong result
+ * for someone who has su'd to a different user.
p = getlogin();
+ */
if (p == NULL || *p == '\0') {
pw = getpwuid(getuid());
if (pw != NULL)
@@ -359,7 +366,7 @@
int levelfound[NLEVELS];
if (!gotscores)
- getscores((FILE **)NULL);
+ getscores(NULL);
(void)printf("\n\t\t\t Tetris High Scores\n");
/*
diff -Naur --exclude '*.swp' bsd-games-2.17/tetris/scores.h bsd-games-2.17.new/tetris/scores.h
--- bsd-games-2.17/tetris/scores.h 2006-04-22 20:46:56.000000000 -0700
+++ bsd-games-2.17.new/tetris/scores.h 2006-04-22 16:30:46.000000000 -0700
@@ -48,5 +48,6 @@
#define MAXSCORES 9 /* maximum high score entries per person */
#define EXPIRATION (5L * 365 * 24 * 60 * 60)
-void savescore(int);
+void savescore(int, FILE *);
+void open_score(int *, FILE **);
void showscores(int);
diff -Naur --exclude '*.swp' bsd-games-2.17/tetris/tetris.c bsd-games-2.17.new/tetris/tetris.c
--- bsd-games-2.17/tetris/tetris.c 2006-04-22 20:46:56.000000000 -0700
+++ bsd-games-2.17.new/tetris/tetris.c 2006-04-22 21:02:27.000000000 -0700
@@ -135,10 +135,15 @@
char key_write[6][10];
int ch, i, j;
int fd;
+ int sd = 0;
+ FILE *sf = (FILE *)NULL;
- gid = getgid();
- egid = getegid();
- setegid(gid);
+ /*
+ * This function has the side effect of dropping setgid privileges.
+ * sd is not used, but is kept around in case we want to add code
+ * to lock shared access to the scoreboard later.
+ */
+ open_score(&sd, &sf);
fd = open("/dev/null", O_RDONLY);
if (fd < 3)
@@ -307,7 +312,7 @@
(void)printf("Your score: %d point%s x level %d = %d\n",
score, score == 1 ? "" : "s", level, score * level);
- savescore(level);
+ savescore(level, sf);
printf("\nHit RETURN to see high scores, ^C to skip.\n");
