Author: mturk
Date: Wed Aug 12 21:02:46 2009
New Revision: 803710
URL: http://svn.apache.org/viewvc?rev=803710&view=rev
Log:
Add magic to shared memory for an extra security
Modified:
commons/sandbox/runtime/trunk/src/main/native/include/acr_shm.h
commons/sandbox/runtime/trunk/src/main/native/os/unix/shm.c
commons/sandbox/runtime/trunk/src/main/native/os/win32/shm.c
Modified: commons/sandbox/runtime/trunk/src/main/native/include/acr_shm.h
URL:
http://svn.apache.org/viewvc/commons/sandbox/runtime/trunk/src/main/native/include/acr_shm.h?rev=803710&r1=803709&r2=803710&view=diff
==============================================================================
--- commons/sandbox/runtime/trunk/src/main/native/include/acr_shm.h (original)
+++ commons/sandbox/runtime/trunk/src/main/native/include/acr_shm.h Wed Aug 12
21:02:46 2009
@@ -32,6 +32,11 @@
*/
/**
+ * Any value will do
+ */
+#define ACR_SHM_MAGIC 0xB2303964
+
+/**
* Private, platform-specific data struture representing a shared memory
* segment.
*/
Modified: commons/sandbox/runtime/trunk/src/main/native/os/unix/shm.c
URL:
http://svn.apache.org/viewvc/commons/sandbox/runtime/trunk/src/main/native/os/unix/shm.c?rev=803710&r1=803709&r2=803710&view=diff
==============================================================================
--- commons/sandbox/runtime/trunk/src/main/native/os/unix/shm.c (original)
+++ commons/sandbox/runtime/trunk/src/main/native/os/unix/shm.c Wed Aug 12
21:02:46 2009
@@ -38,6 +38,13 @@
#define ACR_SHM_OWNER 0
#define ACR_SHM_CHILD 1
+typedef struct memblock_t {
+ acr_uint32_t magic; /* Is this our memeory */
+ pid_t creator; /* Creator's process ID */
+ acr_size_t size;
+ acr_size_t length;
+} memblock_t;
+
struct acr_shm_t {
void *base; /* base real address */
void *usable; /* base usable address */
@@ -186,6 +193,7 @@
ACR_DECLARE(int) ACR_ShmCreate(JNIEnv *_E, acr_size_t reqsize,
const acr_pchar_t *filename)
{
+ memblock_t hdr;
acr_shm_t *shm = NULL;
struct shmid_ds shmbuf;
int file; /* file where metadata is stored */
@@ -282,9 +290,13 @@
goto cleanup;
}
- nbytes = sizeof(reqsize);
+ nbytes = sizeof(memblock_t);
+ hdr.creator = getpid();
+ hdr.magic = ACR_SHM_MAGIC;
+ hdr.size = shm->reqsize;
+ hdr.length = shm->realsize;
do {
- rc = write(file,(const void *)&reqsize, nbytes);
+ rc = write(file,(const void *)&hdr, nbytes);
} while (rc == (acr_size_t)-1 && errno == EINTR);
if (rc == -1) {
rc = ACR_GET_OS_ERROR();
@@ -317,6 +329,7 @@
ACR_DECLARE(int) ACR_ShmAttach(JNIEnv *_E,
const acr_pchar_t *filename)
{
+ memblock_t hdr;
acr_shm_t *shm = NULL;
int file; /* file where metadata is stored */
int rc;
@@ -343,10 +356,10 @@
goto cleanup;
}
- nbytes = sizeof(shm->reqsize);
+ nbytes = sizeof(memblock_t);
do {
- rc = read(file, (void *)&(shm->reqsize), nbytes);
+ rc = read(file, (void *)&hdr, nbytes);
} while (rc == -1 && errno == EINTR);
if (rc != nbytes) {
/* Wrong format */
@@ -358,8 +371,13 @@
if (rc) {
goto cleanup;
}
-
- shm->shmkey = ftok(filename, 1);
+ if (hdr.magic != ACR_SHM_MAGIC) {
+ /* Not created by us or corrupted */
+ rc = ACR_EBADF;
+ goto cleanup;
+ }
+ shm->reqsize = hdr.size;
+ shm->shmkey = ftok(filename, 1);
if (shm->shmkey == (key_t)-1) {
rc = ACR_GET_OS_ERROR();
goto cleanup;
Modified: commons/sandbox/runtime/trunk/src/main/native/os/win32/shm.c
URL:
http://svn.apache.org/viewvc/commons/sandbox/runtime/trunk/src/main/native/os/win32/shm.c?rev=803710&r1=803709&r2=803710&view=diff
==============================================================================
--- commons/sandbox/runtime/trunk/src/main/native/os/win32/shm.c (original)
+++ commons/sandbox/runtime/trunk/src/main/native/os/win32/shm.c Wed Aug 12
21:02:46 2009
@@ -27,8 +27,10 @@
#define ACR_SHM_CHILD 1
typedef struct memblock_t {
- acr_size_t size;
- acr_size_t length;
+ acr_uint32_t magic; /* Is this our memeory */
+ DWORD creator; /* Creator's process ID */
+ acr_size_t size;
+ acr_size_t length;
} memblock_t;
struct acr_shm_t {
@@ -134,6 +136,11 @@
hfile = INVALID_HANDLE_VALUE;
reskey = NULL;
}
+ else if (_wcsnicmp(filename, L"PAGEFILE:", 9) == 0) {
+ /* Use pagefile instead real file */
+ hfile = INVALID_HANDLE_VALUE;
+ reskey = res_name_from_filenamew(ACR_DT_SHM, keybuf, filename);
+ }
/* Name-based shared memory */
else {
/* Do file backed, which is not an inherited handle
@@ -193,8 +200,10 @@
shm->usrmem = (char*)base + sizeof(memblock_t);
shm->length = reqsize - sizeof(memblock_t);;
- shm->memblk->length = shm->length;
- shm->memblk->size = shm->size;
+ shm->memblk->magic = ACR_SHM_MAGIC;
+ shm->memblk->creator = GetCurrentProcessId();
+ shm->memblk->length = shm->length;
+ shm->memblk->size = shm->size;
if (filename) {
shm->filename = ACR_StrdupW(_E, THROW_FMARK, filename);
if (!shm->filename) {
