diff options
Diffstat (limited to 'pango/opentype/hb-open-types-private.hh')
| -rw-r--r-- | pango/opentype/hb-open-types-private.hh | 105 |
1 files changed, 102 insertions, 3 deletions
diff --git a/pango/opentype/hb-open-types-private.hh b/pango/opentype/hb-open-types-private.hh index 98efde47..a8549e2b 100644 --- a/pango/opentype/hb-open-types-private.hh +++ b/pango/opentype/hb-open-types-private.hh @@ -29,6 +29,8 @@ #include "hb-private.h" +#include "hb-blob.h" + #define NO_INDEX ((unsigned int) 0xFFFF) #define NO_CONTEXT ((unsigned int) 0x110000) @@ -36,6 +38,38 @@ #define MAX_NESTING_LEVEL 8 + +/* + * Sanitize + */ + +typedef struct _hb_sanitize_context_t hb_sanitize_context_t; +struct _hb_sanitize_context_t +{ + const char *start, *end; + hb_blob_t *blob; +}; + +#define SANITIZE_ARG_DEF \ + hb_sanitize_context_t *context +#define SANITIZE_ARG \ + context + +#define SANITIZE(X) HB_LIKELY ((X).sanitize (SANITIZE_ARG)) +#define SANITIZE2(X,Y) SANITIZE (X) && SANITIZE (Y) + +#define SANITIZE_THIS(X) HB_LIKELY ((X).sanitize (SANITIZE_ARG, (const char *) this)) +#define SANITIZE_THIS2(X,Y) SANITIZE_THIS (X) && SANITIZE_THIS (Y) + +#define SANITIZE_SELF() SANITIZE_OBJ (*this) +#define SANITIZE_OBJ(X) SANITIZE_MEM(&(X), sizeof (X)) +#define SANITIZE_GET_SIZE() SANITIZE_MEM (this, this->get_size ()) + +#define SANITIZE_MEM(B,L) HB_LIKELY (context->start <= (const char *)(B) && (const char *)(B) + (L) <= context->end) /* XXX overflow */ + +#define NEUTER(Var, Val) (false) + + /* * Array types */ @@ -208,6 +242,7 @@ struct Null <Type> \ inline NAME& operator = (TYPE i) { (TYPE&) v = BIG_ENDIAN (i); return *this; } \ inline operator TYPE(void) const { return BIG_ENDIAN ((TYPE&) v); } \ inline bool operator== (NAME o) const { return (TYPE&) v == (TYPE&) o.v; } \ + inline bool sanitize (SANITIZE_ARG_DEF) { return SANITIZE_SELF (); } \ private: char v[BYTES]; \ }; \ ASSERT_SIZE (NAME, BYTES) @@ -257,6 +292,13 @@ struct OffsetTo : Offset if (HB_UNLIKELY (!offset)) return Null(Type); return *(const Type*)((const char *) base + offset); } + + inline bool sanitize (SANITIZE_ARG_DEF, const void *base) { + if (!SANITIZE_OBJ (*this)) return false; + unsigned int offset = *this; + if (HB_UNLIKELY (!offset)) return true; + return SANITIZE (*(Type*)((char *) base + offset)) || NEUTER (*this, 0); + } }; template <typename Base, typename Type> inline const Type& operator + (const Base &base, OffsetTo<Type> offset) { return offset (base); } @@ -270,6 +312,13 @@ struct LongOffsetTo : LongOffset if (HB_UNLIKELY (!offset)) return Null(Type); return *(const Type*)((const char *) base + offset); } + + inline bool sanitize (SANITIZE_ARG_DEF, const void *base) { + if (!SANITIZE (*this)) return false; + unsigned int offset = *this; + if (HB_UNLIKELY (!offset)) return true; + return SANITIZE (*(Type*)((char *) base + offset)) || NEUTER (*this, 0); + } }; template <typename Base, typename Type> inline const Type& operator + (const Base &base, LongOffsetTo<Type> offset) { return offset (base); } @@ -320,6 +369,16 @@ struct ArrayOf inline unsigned int get_size () const { return sizeof (len) + len * sizeof (array[0]); } + inline bool sanitize (SANITIZE_ARG_DEF) { + if (!(SANITIZE (len) && SANITIZE_GET_SIZE())) return false; + /* For non-offset types, this shouldn't be needed + unsigned int count = len; + for (unsigned int i = 0; i < count; i++) + if (!SANITIZE (array[i])) + return false; + */ + } + USHORT len; Type array[]; }; @@ -337,6 +396,14 @@ struct HeadlessArrayOf inline unsigned int get_size () const { return sizeof (len) + (len ? len - 1 : 0) * sizeof (array[0]); } + inline bool sanitize (SANITIZE_ARG_DEF) { + if (!(SANITIZE_SELF () && SANITIZE_GET_SIZE())) return false; + unsigned int count = len ? len - 1 : 0; + for (unsigned int i = 0; i < count; i++) + if (!SANITIZE (array[i])) + return false; + } + USHORT len; Type array[]; }; @@ -353,21 +420,53 @@ struct LongArrayOf inline unsigned int get_size () const { return sizeof (len) + len * sizeof (array[0]); } + inline bool sanitize (SANITIZE_ARG_DEF) { + if (!(SANITIZE_SELF () && SANITIZE_GET_SIZE())) return false; + unsigned int count = len; + for (unsigned int i = 0; i < count; i++) + if (!SANITIZE (array[i])) + return false; + } + ULONG len; Type array[]; }; /* Array of Offset's */ template <typename Type> -struct OffsetArrayOf : ArrayOf<OffsetTo<Type> > {}; +struct OffsetArrayOf : ArrayOf<OffsetTo<Type> > { + inline bool sanitize (SANITIZE_ARG_DEF, const char *base) { + if (!(SANITIZE (this->len) && SANITIZE_GET_SIZE())) return false; + unsigned int count = this->len; + for (unsigned int i = 0; i < count; i++) + if (!this->array[i].sanitize (SANITIZE_ARG, base)) + return false; + } +}; /* Array of LongOffset's */ template <typename Type> -struct LongOffsetArrayOf : ArrayOf<LongOffsetTo<Type> > {}; +struct LongOffsetArrayOf : ArrayOf<LongOffsetTo<Type> > { + inline bool sanitize (SANITIZE_ARG_DEF, const char *base) { + if (!(SANITIZE (this->len) && SANITIZE_GET_SIZE())) return false; + unsigned int count = this->len; + for (unsigned int i = 0; i < count; i++) + if (!this->array[i].sanitize (SANITIZE_ARG, base)) + return false; + } +}; /* LongArray of LongOffset's */ template <typename Type> -struct LongOffsetLongArrayOf : LongArrayOf<LongOffsetTo<Type> > {}; +struct LongOffsetLongArrayOf : LongArrayOf<LongOffsetTo<Type> > { + inline bool sanitize (SANITIZE_ARG_DEF, const char *base) { + if (!(SANITIZE (this->len) && SANITIZE_GET_SIZE())) return false; + unsigned int count = this->len; + for (unsigned int i = 0; i < count; i++) + if (!this->array[i].sanitize (SANITIZE_ARG, base)) + return false; + } +}; /* An array type is one that contains a variable number of objects * as its last item. An array object is extended with get_len() |