#include "putty.h"
#include "storage.h"
-static const char *const puttystr = PUTTY_REG_POS "\\Sessions";
+#include <shlobj.h>
+#ifndef CSIDL_APPDATA
+#define CSIDL_APPDATA 0x001a
+#endif
+#ifndef CSIDL_LOCAL_APPDATA
+#define CSIDL_LOCAL_APPDATA 0x001c
+#endif
-static char seedpath[2 * MAX_PATH + 10] = "\0";
+static const char *const puttystr = PUTTY_REG_POS "\\Sessions";
static const char hex[16] = "0123456789ABCDEF";
+static int tried_shgetfolderpath = FALSE;
+static HMODULE shell32_module = NULL;
+typedef HRESULT (WINAPI *p_SHGetFolderPath_t)
+ (HWND, int, HANDLE, DWORD, LPTSTR);
+static p_SHGetFolderPath_t p_SHGetFolderPath = NULL;
+
static void mungestr(const char *in, char *out)
{
int candot = 0;
}
/*
- * Find the random seed file path and store it in `seedpath'.
+ * Open (or delete) the random seed file.
*/
-static void get_seedpath(void)
+enum { DEL, OPEN_R, OPEN_W };
+static int try_random_seed(char const *path, int action, HANDLE *ret)
+{
+ if (action == DEL) {
+ remove(path);
+ *ret = INVALID_HANDLE_VALUE;
+ return FALSE; /* so we'll do the next ones too */
+ }
+
+ *ret = CreateFile(path,
+ action == OPEN_W ? GENERIC_WRITE : GENERIC_READ,
+ action == OPEN_W ? 0 : (FILE_SHARE_READ |
+ FILE_SHARE_WRITE),
+ NULL,
+ action == OPEN_W ? CREATE_ALWAYS : OPEN_EXISTING,
+ action == OPEN_W ? FILE_ATTRIBUTE_NORMAL : 0,
+ NULL);
+
+ return (*ret != INVALID_HANDLE_VALUE);
+}
+
+static HANDLE access_random_seed(int action)
{
HKEY rkey;
DWORD type, size;
+ HANDLE rethandle;
+ char seedpath[2 * MAX_PATH + 10] = "\0";
- size = sizeof(seedpath);
+ /*
+ * Iterate over a selection of possible random seed paths until
+ * we find one that works.
+ *
+ * We do this iteration separately for reading and writing,
+ * meaning that we will automatically migrate random seed files
+ * if a better location becomes available (by reading from the
+ * best location in which we actually find one, and then
+ * writing to the best location in which we can _create_ one).
+ */
+ /*
+ * First, try the location specified by the user in the
+ * Registry, if any.
+ */
+ size = sizeof(seedpath);
if (RegOpenKey(HKEY_CURRENT_USER, PUTTY_REG_POS, &rkey) ==
ERROR_SUCCESS) {
int ret = RegQueryValueEx(rkey, "RandSeedFile",
if (ret != ERROR_SUCCESS || type != REG_SZ)
seedpath[0] = '\0';
RegCloseKey(rkey);
- } else
- seedpath[0] = '\0';
- if (!seedpath[0]) {
+ if (*seedpath && try_random_seed(seedpath, action, &rethandle))
+ return rethandle;
+ }
+
+ /*
+ * Next, try the user's local Application Data directory,
+ * followed by their non-local one. This is found using the
+ * SHGetFolderPath function, which won't be present on all
+ * versions of Windows.
+ */
+ if (!tried_shgetfolderpath) {
+ /* This is likely only to bear fruit on systems with IE5+
+ * installed, or WinMe/2K+. There is some faffing with
+ * SHFOLDER.DLL we could do to try to find an equivalent
+ * on older versions of Windows if we cared enough.
+ * However, the invocation below requires IE5+ anyway,
+ * so stuff that. */
+ shell32_module = LoadLibrary("SHELL32.DLL");
+ if (shell32_module) {
+ p_SHGetFolderPath = (p_SHGetFolderPath_t)
+ GetProcAddress(shell32_module, "SHGetFolderPathA");
+ }
+ }
+ if (p_SHGetFolderPath) {
+ if (SUCCEEDED(p_SHGetFolderPath(NULL, CSIDL_LOCAL_APPDATA,
+ NULL, SHGFP_TYPE_CURRENT, seedpath))) {
+ strcat(seedpath, "\\PUTTY.RND");
+ if (try_random_seed(seedpath, action, &rethandle))
+ return rethandle;
+ }
+
+ if (SUCCEEDED(p_SHGetFolderPath(NULL, CSIDL_APPDATA,
+ NULL, SHGFP_TYPE_CURRENT, seedpath))) {
+ strcat(seedpath, "\\PUTTY.RND");
+ if (try_random_seed(seedpath, action, &rethandle))
+ return rethandle;
+ }
+ }
+
+ /*
+ * Failing that, try %HOMEDRIVE%%HOMEPATH% as a guess at the
+ * user's home directory.
+ */
+ {
int len, ret;
len =
ret =
GetEnvironmentVariable("HOMEPATH", seedpath + len,
sizeof(seedpath) - len);
- if (ret == 0) { /* probably win95; store in \WINDOWS */
- GetWindowsDirectory(seedpath, sizeof(seedpath));
- len = strlen(seedpath);
- } else
- len += ret;
- strcpy(seedpath + len, "\\PUTTY.RND");
+ if (ret != 0) {
+ strcat(seedpath, "\\PUTTY.RND");
+ if (try_random_seed(seedpath, action, &rethandle))
+ return rethandle;
+ }
}
+
+ /*
+ * And finally, fall back to C:\WINDOWS.
+ */
+ GetWindowsDirectory(seedpath, sizeof(seedpath));
+ strcat(seedpath, "\\PUTTY.RND");
+ if (try_random_seed(seedpath, action, &rethandle))
+ return rethandle;
+
+ /*
+ * If even that failed, give up.
+ */
+ return INVALID_HANDLE_VALUE;
}
void read_random_seed(noise_consumer_t consumer)
{
- HANDLE seedf;
-
- if (!seedpath[0])
- get_seedpath();
-
- seedf = CreateFile(seedpath, GENERIC_READ,
- FILE_SHARE_READ | FILE_SHARE_WRITE,
- NULL, OPEN_EXISTING, 0, NULL);
+ HANDLE seedf = access_random_seed(OPEN_R);
if (seedf != INVALID_HANDLE_VALUE) {
while (1) {
void write_random_seed(void *data, int len)
{
- HANDLE seedf;
-
- if (!seedpath[0])
- get_seedpath();
-
- seedf = CreateFile(seedpath, GENERIC_WRITE, 0,
- NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
+ HANDLE seedf = access_random_seed(OPEN_W);
if (seedf != INVALID_HANDLE_VALUE) {
DWORD lenwritten;
char name[MAX_PATH + 1];
/* ------------------------------------------------------------
- * Wipe out the random seed file.
+ * Wipe out the random seed file, in all of its possible
+ * locations.
*/
- if (!seedpath[0])
- get_seedpath();
- remove(seedpath);
+ access_random_seed(DEL);
/* ------------------------------------------------------------
* Destroy all registry information associated with PuTTY.