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Index: src/coolkey/machdep.cpp
===================================================================
RCS file: /cvs/dirsec/coolkey/src/coolkey/machdep.cpp,v
retrieving revision 1.4
diff -u -r1.4 machdep.cpp
--- src/coolkey/machdep.cpp 14 Feb 2007 00:46:28 -0000 1.4
+++ src/coolkey/machdep.cpp 15 Aug 2007 01:41:11 -0000
@@ -185,12 +185,20 @@
#define MAP_INHERIT 0
#endif
+#ifndef BASEPATH
+#ifdef MAC
+#define BASEPATH "/var"
+#else
+#define BASEPATH "/var/cache"
+#endif
+#endif
+
#ifdef FULL_CLEANUP
#define RESERVED_OFFSET 256
-#define MEMSEGPATH "/tmp/.pk11ipc"
+#define MEMSEGPATH BASEPATH"/coolkey-lock"
#else
#define RESERVED_OFFSET 0
-#define MEMSEGPATH "/tmp/.pk11ipc1"
+#define MEMSEGPATH BASEPATH"/coolkey"
#endif
struct SHMemData {
@@ -208,11 +216,6 @@
#ifdef FULL_CLEANUP
flock(fd,LOCK_EX);
unsigned long ref = --(*(unsigned long *)addr);
-#ifdef notdef
- if (ref == 0) {
- unlink(path);
- }
-#endif
flock(fd, LOCK_UN);
#endif
munmap(addr,size+RESERVED_OFFSET);
@@ -225,6 +228,73 @@
}
}
+/*
+ * The cache directory is shared and accessible by anyone, make
+ * sure the cache file we are opening is really a valid cache file.
+ */
+int safe_open(char *path, int flags, int mode, int size)
+{
+ struct stat buf;
+ int fd, ret;
+
+ fd = open (path, flags|O_NOFOLLOW, mode);
+
+ if (fd < 0) {
+ return fd;
+ }
+
+ ret = fstat(fd, &buf);
+ if (ret < 0) {
+ close (fd);
+ return ret;
+ }
+
+ /* our cache files are pretty specific, make sure we are looking
+ * at the correct one */
+
+ /* first, we should own the file ourselves, don't open a file
+ * that someone else wanted us to see. */
+ if (buf.st_uid != getuid()) {
+ close(fd);
+ errno = EACCES;
+ return -1;
+ }
+
+ /* next, there should only be one link in this file. Don't
+ * use this code to trash another file */
+ if (buf.st_nlink != 1) {
+ close(fd);
+ errno = EMLINK;
+ return -1;
+ }
+
+ /* next, This better be a regular file */
+ if (!S_ISREG(buf.st_mode)) {
+ close(fd);
+ errno = EACCES;
+ return -1;
+ }
+
+ /* if the permissions don't match, something is wrong */
+ if ((buf.st_mode & 03777) != mode) {
+ close(fd);
+ errno = EACCES;
+ return -1;
+ }
+
+ /* finally the file should be the correct size. This
+ * check isn't so much to protect from an attack, as it is to
+ * detect a corrupted cache file */
+ if (buf.st_size != size) {
+ close(fd);
+ errno = EACCES;
+ return -1;
+ }
+
+ /* OK, the file checked out, ok to continue */
+ return fd;
+}
+
SHMem::SHMem(): shmemData(0) {}
SHMem *
@@ -248,7 +318,7 @@
return NULL;
}
int mask = umask(0);
- int ret = mkdir (MEMSEGPATH, 0777);
+ int ret = mkdir (MEMSEGPATH, 01777);
umask(mask);
if ((ret == -1) && (errno != EEXIST)) {
delete shmemData;
@@ -264,21 +334,16 @@
shmemData->path[sizeof(MEMSEGPATH)-1] = '/';
strcpy(&shmemData->path[sizeof(MEMSEGPATH)],name);
- int mode = 0777;
- if (strcmp(name,"token_names") != 0) {
- /* each user gets his own uid array */
- sprintf(uid_str, "-%u",getuid());
- strcat(shmemData->path,uid_str);
- mode = 0700;
- }
+ sprintf(uid_str, "-%u",getuid());
+ strcat(shmemData->path,uid_str);
+ int mode = 0600;
+
shmemData->fd = open(shmemData->path,
O_CREAT|O_RDWR|O_EXCL|O_APPEND|O_EXLOCK, mode);
- if (shmemData->fd < 0) {
- needInit = false;
- shmemData->fd = open(shmemData->path,O_RDWR|O_EXLOCK, mode);
- } else {
+ if (shmemData->fd >= 0) {
char *buf;
int len = size+RESERVED_OFFSET;
+ int ret;
buf = (char *)calloc(1,len);
if (!buf) {
@@ -289,8 +354,22 @@
delete shmemData;
return NULL;
}
- write(shmemData->fd,buf,len);
+ ret = write(shmemData->fd,buf,len);
+ if (ret != len) {
+ unlink(shmemData->path);
+#ifdef FULL_CLEANUP
+ flock(shmemData->fd, LOCK_UN);
+#endif
+ delete shmemData;
+ return NULL;
+ }
+
free(buf);
+ } else if (errno == EEXIST) {
+ needInit = false;
+
+ shmemData->fd = safe_open(shmemData->path,O_RDWR|O_EXLOCK, mode,
+ size+RESERVED_OFFSET);
}
if (shmemData->fd < 0) {
delete shmemData;
|
