Make crypt struct opaque.

4 files changed, 118 insertions, 92 deletions

diff --git a/apps/win_main.c b/apps/win_main.c
index 5e513c89..0054ca17 100644
--- a/apps/win_main.c
+++ b/apps/win_main.c
@@ -171,17 +171,15 @@ dloginfoproc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
 
 		if (xref->crypt)
 		{
-			sprintf(buf, "Standard %d bit %s", xref->crypt->length,
-				xref->crypt->strf.method == PDF_CRYPT_AESV2 ? "AES" : "RC4");
-			SetDlgItemTextA(hwnd, 0x12, buf);
+			SetDlgItemTextA(hwnd, 0x12, "Encrypted.");
 			strcpy(buf, "");
-			if (xref->crypt->p & (1 << 2))
+			if (pdf_has_permission(xref, PDF_PERM_PRINT))
 				strcat(buf, "print, ");
-			if (xref->crypt->p & (1 << 3))
+			if (pdf_has_permission(xref, PDF_PERM_CHANGE))
 				strcat(buf, "modify, ");
-			if (xref->crypt->p & (1 << 4))
+			if (pdf_has_permission(xref, PDF_PERM_COPY))
 				strcat(buf, "copy, ");
-			if (xref->crypt->p & (1 << 5))
+			if (pdf_has_permission(xref, PDF_PERM_NOTES))
 				strcat(buf, "annotate, ");
 			if (strlen(buf) > 2)
 				buf[strlen(buf)-2] = 0;
diff --git a/pdf/mupdf.h b/pdf/mupdf.h
index 228cd714..8d3b5ac4 100644
--- a/pdf/mupdf.h
+++ b/pdf/mupdf.h
@@ -42,78 +42,11 @@ fz_obj *pdf_to_utf8_name(fz_obj *src);
 char *pdf_from_ucs2(unsigned short *str);
 
 /*
- * Encryption
- */
-
-/* Permission flag bits */
-#define PDF_PERM_PRINT (1<<2)
-#define PDF_PERM_CHANGE (1<<3)
-#define PDF_PERM_COPY (1<<4)
-#define PDF_PERM_NOTES (1<<5)
-#define PDF_PERM_FILL_FORM (1<<8)
-#define PDF_PERM_ACCESSIBILITY (1<<9)
-#define PDF_PERM_ASSEMBLE (1<<10)
-#define PDF_PERM_HIGH_RES_PRINT (1<<11)
-#define PDF_DEFAULT_PERM_FLAGS 0xfffc
-
-typedef struct pdf_crypt_s pdf_crypt;
-typedef struct pdf_crypt_filter_s pdf_crypt_filter;
-
-enum
-{
-	PDF_CRYPT_NONE,
-	PDF_CRYPT_RC4,
-	PDF_CRYPT_AESV2,
-	PDF_CRYPT_AESV3,
-	PDF_CRYPT_UNKNOWN,
-};
-
-struct pdf_crypt_filter_s
-{
-	int method;
-	int length;
-};
-
-struct pdf_crypt_s
-{
-	unsigned char id_string[32];
-	int id_length;
-
-	int v;
-	int length;
-	fz_obj *cf;
-	pdf_crypt_filter stmf;
-	pdf_crypt_filter strf;
-
-	int r;
-	unsigned char o[48];
-	unsigned char u[48];
-	unsigned char oe[32];
-	unsigned char ue[32];
-	int p;
-	int encrypt_metadata;
-
-	unsigned char key[32]; /* decryption key generated from password */
-};
-
-/* crypt.c */
-fz_error pdf_new_crypt(pdf_crypt **cp, fz_obj *enc, fz_obj *id);
-void pdf_free_crypt(pdf_crypt *crypt);
-
-fz_error pdf_parse_crypt_filter(pdf_crypt_filter *cf, fz_obj *dict, int defaultlength);
-fz_stream *pdf_open_crypt(fz_stream *chain, pdf_crypt *crypt, pdf_crypt_filter *cf, int num, int gen);
-void pdf_crypt_obj(pdf_crypt *crypt, fz_obj *obj, int num, int gen);
-
-int pdf_needs_password(pdf_xref *xref);
-int pdf_authenticate_password(pdf_xref *xref, char *pw);
-
-void pdf_debug_crypt(pdf_crypt *crypt);
-
-/*
  * xref and object / stream api
  */
 
 typedef struct pdf_xref_entry_s pdf_xref_entry;
+typedef struct pdf_crypt_s pdf_crypt;
 
 struct pdf_xref_entry_s
 {
@@ -170,6 +103,36 @@ void pdf_debug_xref(pdf_xref *);
 void pdf_resize_xref(pdf_xref *xref, int newcap);
 
 /*
+ * Encryption
+ */
+
+enum
+{
+	PDF_PERM_PRINT = 1 << 2,
+	PDF_PERM_CHANGE = 1 << 3,
+	PDF_PERM_COPY = 1 << 4,
+	PDF_PERM_NOTES = 1 << 5,
+	PDF_PERM_FILL_FORM = 1 << 8,
+	PDF_PERM_ACCESSIBILITY = 1 << 9,
+	PDF_PERM_ASSEMBLE = 1 << 10,
+	PDF_PERM_HIGH_RES_PRINT = 1 << 11,
+	PDF_DEFAULT_PERM_FLAGS = 0xfffc
+};
+
+fz_error pdf_new_crypt(pdf_crypt **cp, fz_obj *enc, fz_obj *id);
+void pdf_free_crypt(pdf_crypt *crypt);
+
+void pdf_crypt_obj(pdf_crypt *crypt, fz_obj *obj, int num, int gen);
+fz_stream *pdf_open_crypt(fz_stream *chain, pdf_crypt *crypt, int num, int gen);
+fz_stream *pdf_open_crypt_with_filter(fz_stream *chain, pdf_crypt *crypt, char *name, int num, int gen);
+
+int pdf_needs_password(pdf_xref *xref);
+int pdf_authenticate_password(pdf_xref *xref, char *pw);
+int pdf_has_permission(pdf_xref *xref, int p);
+
+void pdf_debug_crypt(pdf_crypt *crypt);
+
+/*
  * Resource store
  */
 
diff --git a/pdf/pdf_crypt.c b/pdf/pdf_crypt.c
index d29e756d..edd3e985 100644
--- a/pdf/pdf_crypt.c
+++ b/pdf/pdf_crypt.c
@@ -1,6 +1,47 @@
 #include "fitz.h"
 #include "mupdf.h"
 
+enum
+{
+	PDF_CRYPT_NONE,
+	PDF_CRYPT_RC4,
+	PDF_CRYPT_AESV2,
+	PDF_CRYPT_AESV3,
+	PDF_CRYPT_UNKNOWN,
+};
+
+typedef struct pdf_crypt_filter_s pdf_crypt_filter;
+
+struct pdf_crypt_filter_s
+{
+	int method;
+	int length;
+};
+
+struct pdf_crypt_s
+{
+	unsigned char id_string[32];
+	int id_length;
+
+	int v;
+	int length;
+	fz_obj *cf;
+	pdf_crypt_filter stmf;
+	pdf_crypt_filter strf;
+
+	int r;
+	unsigned char o[48];
+	unsigned char u[48];
+	unsigned char oe[32];
+	unsigned char ue[32];
+	int p;
+	int encrypt_metadata;
+
+	unsigned char key[32]; /* decryption key generated from password */
+};
+
+static fz_error pdf_parse_crypt_filter(pdf_crypt_filter *cf, fz_obj *dict, int defaultlength);
+
 /*
  * Create crypt object for decrypting strings and streams
  * given the Encryption and ID objects.
@@ -228,7 +269,7 @@ pdf_free_crypt(pdf_crypt *crypt)
  * Parse a CF dictionary entry (PDF 1.7 table 3.22)
  */
 
-fz_error
+static fz_error
 pdf_parse_crypt_filter(pdf_crypt_filter *cf, fz_obj *dict, int defaultlength)
 {
 	fz_obj *obj;
@@ -560,6 +601,14 @@ pdf_needs_password(pdf_xref *xref)
 	return 1;
 }
 
+int
+pdf_has_permission(pdf_xref *xref, int p)
+{
+	if (!xref->crypt)
+		return 1;
+	return xref->crypt->p & p;
+}
+
 /*
  * PDF 1.7 algorithm 3.1 and ExtensionLevel 3 algorithm 3.1a
  *
@@ -679,8 +728,8 @@ pdf_crypt_obj(pdf_crypt *crypt, fz_obj *obj, int num, int gen)
  *
  * Create filter suitable for de/encrypting a stream.
  */
-fz_stream *
-pdf_open_crypt(fz_stream *chain, pdf_crypt *crypt, pdf_crypt_filter *stmf, int num, int gen)
+static fz_stream *
+pdf_open_crypt_imp(fz_stream *chain, pdf_crypt *crypt, pdf_crypt_filter *stmf, int num, int gen)
 {
 	unsigned char key[32];
 	int len;
@@ -696,6 +745,33 @@ pdf_open_crypt(fz_stream *chain, pdf_crypt *crypt, pdf_crypt_filter *stmf, int n
 	return fz_open_copy(chain);
 }
 
+fz_stream *
+pdf_open_crypt(fz_stream *chain, pdf_crypt *crypt, int num, int gen)
+{
+	return pdf_open_crypt_imp(chain, crypt, &crypt->stmf, num, gen);
+}
+
+fz_stream *
+pdf_open_crypt_with_filter(fz_stream *chain, pdf_crypt *crypt, char *name, int num, int gen)
+{
+	fz_error error;
+	pdf_crypt_filter cf;
+
+	if (strcmp(name, "Identity"))
+	{
+		fz_obj *obj = fz_dict_gets(crypt->cf, name);
+		if (fz_is_dict(obj))
+		{
+			error = pdf_parse_crypt_filter(&cf, obj, crypt->length);
+			if (error)
+				fz_catch(error, "cannot parse crypt filter (%d %d R)", fz_to_num(obj), fz_to_gen(obj));
+			else
+				return pdf_open_crypt_imp(chain, crypt, &cf, num, gen);
+		}
+	}
+	return chain;
+}
+
 void pdf_debug_crypt(pdf_crypt *crypt)
 {
 	int i;
diff --git a/pdf/pdf_stream.c b/pdf/pdf_stream.c
index 79b39d07..c2dd8578 100644
--- a/pdf/pdf_stream.c
+++ b/pdf/pdf_stream.c
@@ -113,7 +113,6 @@ build_filter(fz_stream *chain, pdf_xref * xref, fz_obj * f, fz_obj * p, int num,
 
 	else if (!strcmp(s, "Crypt"))
 	{
-		pdf_crypt_filter cf;
 		fz_obj *name;
 
 		if (!xref->crypt)
@@ -123,18 +122,8 @@ build_filter(fz_stream *chain, pdf_xref * xref, fz_obj * f, fz_obj * p, int num,
 		}
 
 		name = fz_dict_gets(p, "Name");
-		if (fz_is_name(name) && strcmp(fz_to_name(name), "Identity") != 0)
-		{
-			fz_obj *obj = fz_dict_get(xref->crypt->cf, name);
-			if (fz_is_dict(obj))
-			{
-				error = pdf_parse_crypt_filter(&cf, obj, xref->crypt->length);
-				if (error)
-					fz_catch(error, "cannot parse crypt filter (%d %d R)", fz_to_num(obj), fz_to_gen(obj));
-				else
-					return pdf_open_crypt(chain, xref->crypt, &cf, num, gen);
-			}
-		}
+		if (fz_is_name(name))
+			return pdf_open_crypt_with_filter(chain, xref->crypt, fz_to_name(name), num, gen);
 
 		return chain;
 	}
@@ -184,7 +173,7 @@ pdf_open_raw_filter(fz_stream *chain, pdf_xref *xref, fz_obj *stmobj, int num, i
 
 	hascrypt = pdf_stream_has_crypt(stmobj);
 	if (xref->crypt && !hascrypt)
-		chain = pdf_open_crypt(chain, xref->crypt, &xref->crypt->stmf, num, gen);
+		chain = pdf_open_crypt(chain, xref->crypt, num, gen);
 
 	return chain;
 }