More arbitrary-limit hunting: retire PASSPHRASE_MAXLEN in the Windows

GUIs of Pageant and PuTTYgen. With that and the prompts_t redesign,
there should no longer be any limit on passphrase length other than
the patience of the user.

git-svn-id: svn://svn.tartarus.org/sgt/putty@9320 cda61777-01e9-0310-a592-d414129be87e

diff --git a/windows/winpgen.c b/windows/winpgen.c
index 1e39105..48a02ec 100644 (file)
--- a/windows/winpgen.c
+++ b/windows/winpgen.c
@@ -5,6 +5,7 @@
 #include <time.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <assert.h>
 
 #define PUTTY_DO_GLOBALS
 
@@ -116,10 +117,8 @@ static void progress_update(void *param, int action, int phase, int iprogress)
 
 extern char ver[];
 
-#define PASSPHRASE_MAXLEN 512
-
 struct PassphraseProcStruct {
-    char *passphrase;
+    char **passphrase;
     char *comment;
 };
 
@@ -129,7 +128,7 @@ struct PassphraseProcStruct {
 static int CALLBACK PassphraseProc(HWND hwnd, UINT msg,
                                   WPARAM wParam, LPARAM lParam)
 {
-    static char *passphrase = NULL;
+    static char **passphrase = NULL;
     struct PassphraseProcStruct *p;
 
     switch (msg) {
@@ -157,8 +156,9 @@ static int CALLBACK PassphraseProc(HWND hwnd, UINT msg,
        passphrase = p->passphrase;
        if (p->comment)
            SetDlgItemText(hwnd, 101, p->comment);
-       *passphrase = 0;
-       SetDlgItemText(hwnd, 102, passphrase);
+        burnstr(*passphrase);
+        *passphrase = dupstr("");
+       SetDlgItemText(hwnd, 102, *passphrase);
        return 0;
       case WM_COMMAND:
        switch (LOWORD(wParam)) {
@@ -173,9 +173,8 @@ static int CALLBACK PassphraseProc(HWND hwnd, UINT msg,
            return 0;
          case 102:                    /* edit box */
            if ((HIWORD(wParam) == EN_CHANGE) && passphrase) {
-               GetDlgItemText(hwnd, 102, passphrase,
-                              PASSPHRASE_MAXLEN - 1);
-               passphrase[PASSPHRASE_MAXLEN - 1] = '\0';
+                burnstr(*passphrase);
+                *passphrase = GetDlgItemText_alloc(hwnd, 102);
            }
            return 0;
        }
@@ -617,13 +616,12 @@ void ui_set_state(HWND hwnd, struct MainDlgState *state, int status)
 void load_key_file(HWND hwnd, struct MainDlgState *state,
                   Filename *filename, int was_import_cmd)
 {
-    char passphrase[PASSPHRASE_MAXLEN];
+    char *passphrase;
     int needs_pass;
     int type, realtype;
     int ret;
     const char *errmsg = NULL;
     char *comment;
-    struct PassphraseProcStruct pps;
     struct RSAKey newkey1;
     struct ssh2_userkey *newkey2 = NULL;
 
@@ -646,17 +644,22 @@ void load_key_file(HWND hwnd, struct MainDlgState *state,
     }
 
     comment = NULL;
+    passphrase = NULL;
     if (realtype == SSH_KEYTYPE_SSH1)
        needs_pass = rsakey_encrypted(filename, &comment);
     else if (realtype == SSH_KEYTYPE_SSH2)
        needs_pass = ssh2_userkey_encrypted(filename, &comment);
     else
        needs_pass = import_encrypted(filename, realtype, &comment);
-    pps.passphrase = passphrase;
-    pps.comment = comment;
     do {
+        burnstr(passphrase);
+        passphrase = NULL;
+
        if (needs_pass) {
            int dlgret;
+            struct PassphraseProcStruct pps;
+            pps.passphrase = &passphrase;
+            pps.comment = comment;
            dlgret = DialogBoxParam(hinst,
                                    MAKEINTRESOURCE(210),
                                    NULL, PassphraseProc,
@@ -665,8 +668,9 @@ void load_key_file(HWND hwnd, struct MainDlgState *state,
                ret = -2;
                break;
            }
+            assert(passphrase != NULL);
        } else
-           *passphrase = '\0';
+           passphrase = dupstr("");
        if (type == SSH_KEYTYPE_SSH1) {
            if (realtype == type)
                ret = loadrsakey(filename, &newkey1, passphrase, &errmsg);
@@ -779,6 +783,7 @@ void load_key_file(HWND hwnd, struct MainDlgState *state,
                       MB_OK | MB_ICONINFORMATION);
        }
     }
+    burnstr(passphrase);
 }
 
 /*
@@ -1097,8 +1102,7 @@ static int CALLBACK MainDlgProc(HWND hwnd, UINT msg,
                (struct MainDlgState *) GetWindowLongPtr(hwnd, GWLP_USERDATA);
            if (state->key_exists) {
                char filename[FILENAME_MAX];
-               char passphrase[PASSPHRASE_MAXLEN];
-               char passphrase2[PASSPHRASE_MAXLEN];
+               char *passphrase, *passphrase2;
                 int type, realtype;
 
                 if (state->ssh2)
@@ -1124,16 +1128,17 @@ static int CALLBACK MainDlgProc(HWND hwnd, UINT msg,
                    break;
                 }
 
-               GetDlgItemText(hwnd, IDC_PASSPHRASE1EDIT,
-                              passphrase, sizeof(passphrase));
-               GetDlgItemText(hwnd, IDC_PASSPHRASE2EDIT,
-                              passphrase2, sizeof(passphrase2));
+               passphrase = GetDlgItemText_alloc(hwnd, IDC_PASSPHRASE1EDIT);
+               passphrase2 = GetDlgItemText_alloc(hwnd, IDC_PASSPHRASE2EDIT);
                if (strcmp(passphrase, passphrase2)) {
                    MessageBox(hwnd,
                               "The two passphrases given do not match.",
                               "PuTTYgen Error", MB_OK | MB_ICONERROR);
+                    burnstr(passphrase);
+                    burnstr(passphrase2);
                    break;
                }
+                burnstr(passphrase2);
                if (!*passphrase) {
                    int ret;
                    ret = MessageBox(hwnd,
@@ -1141,8 +1146,10 @@ static int CALLBACK MainDlgProc(HWND hwnd, UINT msg,
                                     "without a passphrase to protect it?",
                                     "PuTTYgen Warning",
                                     MB_YESNO | MB_ICONWARNING);
-                   if (ret != IDYES)
-                       break;
+                   if (ret != IDYES) {
+                        burnstr(passphrase);
+                        break;
+                    }
                }
                if (prompt_keyfile(hwnd, "Save private key as:",
                                   filename, 1, (type == realtype))) {
@@ -1156,8 +1163,10 @@ static int CALLBACK MainDlgProc(HWND hwnd, UINT msg,
                        ret = MessageBox(hwnd, buffer, "PuTTYgen Warning",
                                         MB_YESNO | MB_ICONWARNING);
                        sfree(buffer);
-                       if (ret != IDYES)
+                       if (ret != IDYES) {
+                            burnstr(passphrase);
                            break;
+                        }
                    }
 
                    if (state->ssh2) {
@@ -1185,6 +1194,7 @@ static int CALLBACK MainDlgProc(HWND hwnd, UINT msg,
                                   "PuTTYgen Error", MB_OK | MB_ICONERROR);
                    }
                }
+                burnstr(passphrase);
            }
            break;
          case IDC_SAVEPUB:

diff --git a/windows/winpgnt.c b/windows/winpgnt.c
index 9d59327..e26621c 100644 (file)
--- a/windows/winpgnt.c
+++ b/windows/winpgnt.c
@@ -159,10 +159,8 @@ struct blob {
 };
 static int cmpkeys_ssh2_asymm(void *av, void *bv);
 
-#define PASSPHRASE_MAXLEN 512
-
 struct PassphraseProcStruct {
-    char *passphrase;
+    char **passphrase;
     char *comment;
 };
 
@@ -247,7 +245,7 @@ static HWND passphrase_box;
 static int CALLBACK PassphraseProc(HWND hwnd, UINT msg,
                                   WPARAM wParam, LPARAM lParam)
 {
-    static char *passphrase = NULL;
+    static char **passphrase = NULL;
     struct PassphraseProcStruct *p;
 
     switch (msg) {
@@ -275,8 +273,9 @@ static int CALLBACK PassphraseProc(HWND hwnd, UINT msg,
        passphrase = p->passphrase;
        if (p->comment)
            SetDlgItemText(hwnd, 101, p->comment);
-       *passphrase = 0;
-       SetDlgItemText(hwnd, 102, passphrase);
+        burnstr(*passphrase);
+        *passphrase = dupstr("");
+       SetDlgItemText(hwnd, 102, *passphrase);
        return 0;
       case WM_COMMAND:
        switch (LOWORD(wParam)) {
@@ -291,9 +290,8 @@ static int CALLBACK PassphraseProc(HWND hwnd, UINT msg,
            return 0;
          case 102:                    /* edit box */
            if ((HIWORD(wParam) == EN_CHANGE) && passphrase) {
-               GetDlgItemText(hwnd, 102, passphrase,
-                              PASSPHRASE_MAXLEN - 1);
-               passphrase[PASSPHRASE_MAXLEN - 1] = '\0';
+                burnstr(*passphrase);
+                *passphrase = GetDlgItemText_alloc(hwnd, 102);
            }
            return 0;
        }
@@ -387,7 +385,7 @@ static void keylist_update(void)
  */
 static void add_keyfile(Filename *filename)
 {
-    char passphrase[PASSPHRASE_MAXLEN];
+    char *passphrase;
     struct RSAKey *rkey = NULL;
     struct ssh2_userkey *skey = NULL;
     int needs_pass;
@@ -395,7 +393,6 @@ static void add_keyfile(Filename *filename)
     int attempts;
     char *comment;
     const char *error = NULL;
-    struct PassphraseProcStruct pps;
     int type;
     int original_pass;
        
@@ -523,17 +520,24 @@ static void add_keyfile(Filename *filename)
     attempts = 0;
     if (type == SSH_KEYTYPE_SSH1)
        rkey = snew(struct RSAKey);
-    pps.passphrase = passphrase;
-    pps.comment = comment;
+    passphrase = NULL;
     original_pass = 0;
     do {
+        burnstr(passphrase);
+        passphrase = NULL;
+
        if (needs_pass) {
            /* try all the remembered passphrases first */
            char *pp = index234(passphrases, attempts);
            if(pp) {
-               strcpy(passphrase, pp);
+               passphrase = dupstr(pp);
            } else {
                int dlgret;
+                struct PassphraseProcStruct pps;
+
+                pps.passphrase = &passphrase;
+                pps.comment = comment;
+
                original_pass = 1;
                dlgret = DialogBoxParam(hinst, MAKEINTRESOURCE(210),
                                        NULL, PassphraseProc, (LPARAM) &pps);
@@ -545,9 +549,12 @@ static void add_keyfile(Filename *filename)
                        sfree(rkey);
                    return;                    /* operation cancelled */
                }
+
+                assert(passphrase != NULL);
            }
        } else
-           *passphrase = '\0';
+           passphrase = dupstr("");
+
        if (type == SSH_KEYTYPE_SSH1)
            ret = loadrsakey(filename, rkey, passphrase, &error);
        else {
@@ -562,11 +569,14 @@ static void add_keyfile(Filename *filename)
        attempts++;
     } while (ret == -1);
 
-    /* if they typed in an ok passphrase, remember it */
     if(original_pass && ret) {
-       char *pp = dupstr(passphrase);
-       addpos234(passphrases, pp, 0);
+        /* If they typed in an ok passphrase, remember it */
+       addpos234(passphrases, passphrase, 0);
+    } else {
+        /* Otherwise, destroy it */
+        burnstr(passphrase);
     }
+    passphrase = NULL;
 
     if (comment)
        sfree(comment);