Improved means of IPC between agent and PuTTY

[sgt/putty] / pageantc.c

diff --git a/pageantc.c b/pageantc.c
index e718313..49b588e 100644 (file)
--- a/pageantc.c
+++ b/pageantc.c
@@ -6,12 +6,21 @@
 #include <stdio.h>
 #include <stdlib.h>
 
+#define AGENT_COPYDATA_ID 0x804e50ba   /* random goop */
+#define AGENT_MAX_MSGLEN  8192
+
 #ifdef TESTMODE
 #define debug(x) (printf x)
 #else
 #define debug(x)
 #endif
 
+#define GET_32BIT(cp) \
+    (((unsigned long)(unsigned char)(cp)[0] << 24) | \
+    ((unsigned long)(unsigned char)(cp)[1] << 16) | \
+    ((unsigned long)(unsigned char)(cp)[2] << 8) | \
+    ((unsigned long)(unsigned char)(cp)[3]))
+
 int agent_exists(void) {
     HWND hwnd;
     hwnd = FindWindow("Pageant", "Pageant");
@@ -22,93 +31,10 @@ int agent_exists(void) {
 }
 
 void agent_query(void *in, int inlen, void **out, int *outlen) {
-#if 0
-#define MAILSLOTNAME "\\\\.\\mailslot\\pageant_listener"
-    SECURITY_ATTRIBUTES sa;
-    HANDLE my_mailslot, agent_mailslot;
-    char name[64];
-    char *p;
-    DWORD msglen, byteswritten, bytesread, inid;
-
-    *out = NULL;
-    *outlen = 0;
-
-    agent_mailslot = CreateFile(MAILSLOTNAME, GENERIC_WRITE,
-                                FILE_SHARE_READ, (LPSECURITY_ATTRIBUTES)NULL,
-                                OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL,
-                                (HANDLE)NULL);
-    debug(("opened %s: %p\n", MAILSLOTNAME, agent_mailslot));
-    if (agent_mailslot == INVALID_HANDLE_VALUE)
-        return;
-
-    inid = GetCurrentThreadId();
-    inid--;
-
-    sa.nLength = sizeof(sa);
-    sa.lpSecurityDescriptor = NULL;
-    sa.bInheritHandle = TRUE;
-
-    do {
-        sprintf(name, "\\\\.\\mailslot\\pclient_request_%08x", ++inid);
-        /*
-         * Five-minute timeout.
-         */
-        my_mailslot = CreateMailslot(name, 0, 0, &sa);
-        debug(("mailslot %s: %p\n", name, my_mailslot));
-    } while (my_mailslot == INVALID_HANDLE_VALUE);
-    Sleep(3000);
-
-    msglen = strlen(name) + 1 + inlen;
-    p = malloc(msglen);
-    if (!p) {
-        CloseHandle(my_mailslot);
-        CloseHandle(agent_mailslot);
-        return;
-    }
-
-    strcpy(p, name);
-    memcpy(p+strlen(p)+1, in, inlen);
-
-    debug(("ooh\n"));
-    if (WriteFile(agent_mailslot, p, msglen, &byteswritten, NULL) == 0) {
-        debug(("eek!\n"));
-        free(p);
-        CloseHandle(my_mailslot);
-        CloseHandle(agent_mailslot);
-        return;
-    }
-    debug(("aah\n"));
-    free(p);
-    CloseHandle(agent_mailslot);
-
-    WaitForSingleObject(my_mailslot, 3000000);
-    debug(("waited\n"));
-    if (!GetMailslotInfo(my_mailslot, NULL, &msglen, NULL, NULL)) {
-        CloseHandle(my_mailslot);
-        return;
-    }
-    if (msglen == MAILSLOT_NO_MESSAGE) {
-        debug(("no message\n"));
-        CloseHandle(my_mailslot);
-        return;
-    }
-    debug(("msglen=%d\n", msglen));
-    p = malloc(msglen);
-    if (!p) {
-        CloseHandle(my_mailslot);
-        return;
-    }
-    if (ReadFile(my_mailslot, p, msglen, &bytesread, NULL) == 0 &&
-        bytesread == msglen) {
-        *out = p;
-        *outlen = msglen;
-    }
-    CloseHandle(my_mailslot);
-#endif
     HWND hwnd;
     char mapname[64];
     HANDLE filemap;
-    void *p, *ret;
+    unsigned char *p, *ret;
     int id, retlen;
     COPYDATASTRUCT cds;
 
@@ -119,34 +45,30 @@ void agent_query(void *in, int inlen, void **out, int *outlen) {
     debug(("hwnd is %p\n", hwnd));
     if (!hwnd)
         return;
-    cds.dwData = 0;                    /* FIXME */
-    cds.cbData = inlen;
-    cds.lpData = in;
+    sprintf(mapname, "PageantRequest%08x", GetCurrentThreadId());
+    filemap = CreateFileMapping(INVALID_HANDLE_VALUE, NULL, PAGE_READWRITE,
+                                0, AGENT_MAX_MSGLEN, mapname);
+    if (!filemap)
+        return;
+    p = MapViewOfFile(filemap, FILE_MAP_WRITE, 0, 0, 0);
+    memcpy(p, in, inlen);
+    cds.dwData = AGENT_COPYDATA_ID;
+    cds.cbData = 1+strlen(mapname);
+    cds.lpData = mapname;
     id = SendMessage(hwnd, WM_COPYDATA, (WPARAM)NULL, (LPARAM)&cds);
     debug(("return is %d\n", id));
     if (id > 0) {
-        sprintf(mapname, "PageantReply%08x", id);
-        filemap = OpenFileMapping(FILE_MAP_READ, FALSE, mapname);
-        debug(("name is `%s', filemap is %p\n", mapname, filemap));
-        debug(("error is %d\n", GetLastError()));
-        if (filemap != NULL && filemap != INVALID_HANDLE_VALUE) {
-            p = MapViewOfFile(filemap, FILE_MAP_READ, 0, 0, 0);
-            debug(("p is %p\n", p));
-            if (p) {
-                retlen = *(int *)p;
-                debug(("len is %d\n", retlen));
-                ret = malloc(retlen);
-                if (ret) {
-                    memcpy(ret, ((int *)p) + 1, retlen);
-                    *out = ret;
-                    *outlen = retlen;
-                }
-                UnmapViewOfFile(p);
-            }
-            CloseHandle(filemap);
+        retlen = 4 + GET_32BIT(p);
+        debug(("len is %d\n", retlen));
+        ret = malloc(retlen);
+        if (ret) {
+            memcpy(ret, p, retlen);
+            *out = ret;
+            *outlen = retlen;
         }
-        /* FIXME: tell agent to close its handle too */
     }
+    UnmapViewOfFile(p);
+    CloseHandle(filemap);
 }
 
 #ifdef TESTMODE