Sizing and memory related C fixes.

[FIXED]     mpw_templatesForType now returns a fully allocated array, was relying on undefined behavior before.
[FIXED]     mpw_variantWithName was allocating a badly sized standard string.

MasterPassword/C/mpw-algorithm_v0.c

@@ -11,6 +11,7 @@
 #include <errno.h>
 #include <arpa/inet.h>
 
+#include "mpw-types.h"
 #include "mpw-util.h"
 
 #define MP_N                32768

MasterPassword/C/mpw-algorithm_v1.c

@@ -11,6 +11,7 @@
 #include <errno.h>
 #include <arpa/inet.h>
 
+#include "mpw-types.h"
 #include "mpw-util.h"
 
 #define MP_N                32768

MasterPassword/C/mpw-algorithm_v2.c

@@ -11,6 +11,7 @@
 #include <errno.h>
 #include <arpa/inet.h>
 
+#include "mpw-types.h"
 #include "mpw-util.h"
 
 #define MP_N                32768

MasterPassword/C/mpw-algorithm_v3.c

@@ -11,6 +11,7 @@
 #include <errno.h>
 #include <arpa/inet.h>
 
+#include "mpw-types.h"
 #include "mpw-util.h"
 
 #define MP_N                32768

MasterPassword/C/mpw-types.c

@@ -52,7 +52,7 @@ const MPSiteType mpw_typeWithName(const char *typeName) {
     ftl( "Not a generated type name: %s", stdTypeName );
 }
 
-inline const char **mpw_templatesForType(MPSiteType type, size_t *count) {
+const char **mpw_templatesForType(MPSiteType type, size_t *count) {
 
     if (!(type & MPSiteTypeClassGenerated)) {
         ftl( "Not a generated type: %d", type );
@@ -62,42 +62,42 @@ inline const char **mpw_templatesForType(MPSiteType type, size_t *count) {
 
     switch (type) {
         case MPSiteTypeGeneratedMaximum: {
-            *count = 2;
+            return alloc_array( *count, const char *,
-            return (const char *[]){ "anoxxxxxxxxxxxxxxxxx", "axxxxxxxxxxxxxxxxxno" };
+                    "anoxxxxxxxxxxxxxxxxx", "axxxxxxxxxxxxxxxxxno" );
         }
         case MPSiteTypeGeneratedLong: {
-            *count = 21;
+            return alloc_array( *count, const char *,
-            return (const char *[]){ "CvcvnoCvcvCvcv", "CvcvCvcvnoCvcv", "CvcvCvcvCvcvno",
+                    "CvcvnoCvcvCvcv", "CvcvCvcvnoCvcv", "CvcvCvcvCvcvno",
-                                        "CvccnoCvcvCvcv", "CvccCvcvnoCvcv", "CvccCvcvCvcvno",
+                    "CvccnoCvcvCvcv", "CvccCvcvnoCvcv", "CvccCvcvCvcvno",
-                                        "CvcvnoCvccCvcv", "CvcvCvccnoCvcv", "CvcvCvccCvcvno",
+                    "CvcvnoCvccCvcv", "CvcvCvccnoCvcv", "CvcvCvccCvcvno",
-                                        "CvcvnoCvcvCvcc", "CvcvCvcvnoCvcc", "CvcvCvcvCvccno",
+                    "CvcvnoCvcvCvcc", "CvcvCvcvnoCvcc", "CvcvCvcvCvccno",
-                                        "CvccnoCvccCvcv", "CvccCvccnoCvcv", "CvccCvccCvcvno",
+                    "CvccnoCvccCvcv", "CvccCvccnoCvcv", "CvccCvccCvcvno",
-                                        "CvcvnoCvccCvcc", "CvcvCvccnoCvcc", "CvcvCvccCvccno",
+                    "CvcvnoCvccCvcc", "CvcvCvccnoCvcc", "CvcvCvccCvccno",
-                                        "CvccnoCvcvCvcc", "CvccCvcvnoCvcc", "CvccCvcvCvccno" };
+                    "CvccnoCvcvCvcc", "CvccCvcvnoCvcc", "CvccCvcvCvccno" );
         }
         case MPSiteTypeGeneratedMedium: {
-            *count = 2;
+            return alloc_array( *count, const char *,
-            return (const char *[]){ "CvcnoCvc", "CvcCvcno" };
+                    "CvcnoCvc", "CvcCvcno" );
         }
         case MPSiteTypeGeneratedBasic: {
-            *count = 3;
+            return alloc_array( *count, const char *,
-            return (const char *[]){ "aaanaaan", "aannaaan", "aaannaaa" };
+                    "aaanaaan", "aannaaan", "aaannaaa" );
         }
         case MPSiteTypeGeneratedShort: {
-            *count = 1;
+            return alloc_array( *count, const char *,
-            return (const char *[]){"Cvcn"};
+                    "Cvcn" );
         }
         case MPSiteTypeGeneratedPIN: {
-            *count = 1;
+            return alloc_array( *count, const char *,
-            return (const char *[]){ "nnnn" };
+                    "nnnn" );
         }
         case MPSiteTypeGeneratedName: {
-            *count = 1;
+            return alloc_array( *count, const char *,
-            return (const char *[]) {"cvccvcvcv"};
+                    "cvccvcvcv" );
         }
         case MPSiteTypeGeneratedPhrase: {
-            *count = 3;
+            return alloc_array( *count, const char *,
-            return (const char *[]){ "cvcc cvc cvccvcv cvc", "cvc cvccvcvcv cvcv", "cv cvccv cvc cvcvccv" };
+                    "cvcc cvc cvccvcv cvc", "cvc cvccvcvcv cvcv", "cv cvccv cvc cvcvccv" );
         }
         default: {
             ftl( "Unknown generated type: %d", type );
@@ -114,15 +114,19 @@ const char *mpw_templateForType(MPSiteType type, uint8_t seedByte) {
     if (!count)
         return NULL;
 
-    return templates[seedByte % count];
+    char const *template = templates[seedByte % count];
+    free( templates );
+    return template;
 }
 
 const MPSiteVariant mpw_variantWithName(const char *variantName) {
 
-    char stdVariantName[strlen( variantName )];
+    // Lower-case and trim optionally leading "generated" string from typeName to standardize it.
-    strcpy( stdVariantName, variantName );
+    size_t stdVariantNameSize = strlen( variantName );
-    for (char *vN = stdVariantName; *vN; ++vN)
+    char stdVariantName[stdVariantNameSize + 1];
-        *vN = (char)tolower( *vN );
+    for (size_t c = 0; c < stdVariantNameSize; ++c)
+        stdVariantName[c] = (char)tolower( variantName[c] );
+    stdVariantName[stdVariantNameSize] = '\0';
 
     if (0 == strcmp( stdVariantName, "p" ) || 0 == strcmp( stdVariantName, "password" ))
         return MPSiteVariantPassword;

MasterPassword/C/mpw-types.h

@@ -6,6 +6,8 @@
 //  Copyright (c) 2014 Lyndir. All rights reserved.
 //
 
+#ifndef _MPW_TYPES_H
+#define _MPW_TYPES_H
 #include <stdlib.h>
 #include <stdint.h>
 
@@ -73,9 +75,10 @@ const char *mpw_scopeForVariant(MPSiteVariant variant);
 const MPSiteType mpw_typeWithName(const char *typeName);
 
 /**
- * @return An array of internal strings that express the templates to use for the given type.
+ * @return A newly allocated array of internal strings that express the templates to use for the given type.
  *         The amount of elements in the array is stored in count.
  *         If an unsupported type is given, count will be 0 and will return NULL.
+*          The array needs to be free'ed, the strings themselves must not be free'ed or modified.
  */
 const char **mpw_templatesForType(MPSiteType type, size_t *count);
 /**
@@ -93,3 +96,4 @@ const char *mpw_charactersInClass(char characterClass);
  */
 const char mpw_characterFromClass(char characterClass, uint8_t seedByte);
 
+#endif // _MPW_TYPES_H

MasterPassword/C/mpw-util.h

@@ -25,6 +25,14 @@
 
 //// Buffers and memory.
 
+#define alloc_array(_count, _type, ...) ({ \
+    _type stackElements[] = (_type[]){ __VA_ARGS__ }; \
+    _count = sizeof( stackElements ) / sizeof( _type ); \
+    _type *allocElements = malloc( sizeof( stackElements ) ); \
+    memcpy( allocElements, stackElements, sizeof( stackElements ) ); \
+    allocElements; \
+ })
+
 /** Push a buffer onto a buffer.  reallocs the given buffer and appends the given buffer. */
 void mpw_pushBuf(
         uint8_t **const buffer, size_t *const bufferSize, const void *pushBuffer, const size_t pushSize);

MasterPassword/ObjC/MPAlgorithmV0.m

@@ -730,6 +730,7 @@
         BN_add( permutations, permutations, templatePermutations );
     }
     BN_free( templatePermutations );
+    free( templates );
 
     return [self timeToCrack:timeToCrack permutations:permutations forAttacker:attacker];
 }

MasterPassword/ObjC/Mac/MPPasswordWindowController.m

@@ -605,7 +605,8 @@
     CGDirectDisplayID displayID = [self.window.screen.deviceDescription[@"NSScreenNumber"] unsignedIntValue];
     CGImageRef capturedImage = CGDisplayCreateImage( displayID );
     if (!capturedImage || CGImageGetWidth( capturedImage ) <= 1) {
-        CFRelease( capturedImage );
+        if (capturedImage)
+            CFRelease( capturedImage );
         wrn( @"Failed to capture screen image for display: %d", displayID );
         return;
     }