* options.h, g10.c (main), plaintext.c (handle_plaintext): Add

--max-output option to help people deal with decompression bombs.

g10/ChangeLog

@@ -1,3 +1,8 @@
+2004-02-18  David Shaw  <dshaw@jabberwocky.com>
+
+	* options.h, g10.c (main), plaintext.c (handle_plaintext): Add
+	--max-output option to help people deal with decompression bombs.
+
 2004-02-15  David Shaw  <dshaw@jabberwocky.com>
 
 	* build-packet.c (do_user_id): Do not force a header for attribute

g10/g10.c

@@ -76,6 +76,7 @@ enum cmd_and_opt_values
     oCompress	  = 'z',
     oSetNotation  = 'N',
     oBatch	  = 500,
+    oMaxOutput,
     oSigNotation,
     oCertNotation,
     oShowNotation,
@@ -436,6 +437,7 @@ static ARGPARSE_OPTS opts[] = {
     { oAskCertExpire, "ask-cert-expire",   0, "@"},
     { oNoAskCertExpire, "no-ask-cert-expire",   0, "@"},
     { oOutput, "output",    2, N_("use as output file")},
+    { oMaxOutput, "max-output", 16|4, "@" },
     { oVerbose, "verbose",   0, N_("verbose") },
     { oQuiet,	"quiet",   0, "@"},
     { oNoTTY, "no-tty", 0, "@"},
@@ -1697,6 +1699,7 @@ main( int argc, char **argv )
 
 	  case oArmor: opt.armor = 1; opt.no_armor=0; break;
 	  case oOutput: opt.outfile = pargs.r.ret_str; break;
+	  case oMaxOutput: opt.max_output = pargs.r.ret_ulong; break;
 	  case oQuiet: opt.quiet = 1; break;
 	  case oNoTTY: tty_no_terminal(1); break;
 	  case oDryRun: opt.dry_run = 1; break;

g10/options.h

@@ -1,6 +1,6 @@
 /* options.h
- * Copyright (C) 1998, 1999, 2000, 2001, 2002,
+ * Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003,
- *               2003 Free Software Foundation, Inc.
+ *               2004 Free Software Foundation, Inc.
  *
  * This file is part of GnuPG.
  *
@@ -21,6 +21,7 @@
 #ifndef G10_OPTIONS_H
 #define G10_OPTIONS_H
 
+#include <sys/types.h>
 #include <types.h>
 #include "main.h"
 #include "packet.h"
@@ -43,6 +44,7 @@ struct {
     unsigned debug;
     int armor;
     char *outfile;
+    off_t max_output;
     int dry_run;
     int list_only;
     int textmode;

g10/plaintext.c

@@ -24,6 +24,7 @@
 #include <string.h>
 #include <errno.h>
 #include <assert.h>
+#include <sys/types.h>
 #ifdef HAVE_DOSISH_SYSTEM
 #include <fcntl.h> /* for setmode() */
 #endif
@@ -52,6 +53,7 @@ handle_plaintext( PKT_plaintext *pt, md_filter_context_t *mfx,
 {
     char *fname = NULL;
     FILE *fp = NULL;
+    off_t count=0;
     int rc = 0;
     int c;
     int convert = pt->mode == 't';
@@ -164,8 +166,17 @@ handle_plaintext( PKT_plaintext *pt, md_filter_context_t *mfx,
 		if( c == '\r' )  /* convert to native line ending */
 		    continue;	 /* fixme: this hack might be too simple */
 #endif
-		if( fp ) {
+		if( fp )
-		    if( putc( c, fp ) == EOF ) {
+		  {
+		    if((count++)>opt.max_output)
+		      {
+			log_error("Error writing to `%s': %s\n",
+				  fname,"exceeded --max-output limit\n");
+			rc = G10ERR_WRITE_FILE;
+			goto leave;
+		      }
+		    else if( putc( c, fp ) == EOF )
+		      {
 			log_error("Error writing to `%s': %s\n",
 				  fname, strerror(errno) );
 			rc = G10ERR_WRITE_FILE;
@@ -188,8 +199,18 @@ handle_plaintext( PKT_plaintext *pt, md_filter_context_t *mfx,
 		}
 		if( mfx->md )
 		    md_write( mfx->md, buffer, len );
-		if( fp ) {
+		if( fp )
-		    if( fwrite( buffer, 1, len, fp ) != len ) {
+		  {
+		    if((count+=len)>opt.max_output)
+		      {
+			log_error("Error writing to `%s': %s\n",
+				  fname,"exceeded --max-output limit\n");
+			rc = G10ERR_WRITE_FILE;
+			m_free( buffer );
+			goto leave;
+		      }
+		    else if( fwrite( buffer, 1, len, fp ) != len )
+		      {
 			log_error("Error writing to `%s': %s\n",
 				  fname, strerror(errno) );
 			rc = G10ERR_WRITE_FILE;
@@ -211,8 +232,17 @@ handle_plaintext( PKT_plaintext *pt, md_filter_context_t *mfx,
 		if( convert && c == '\r' )
 		    continue; /* fixme: this hack might be too simple */
 #endif
-		if( fp ) {
+		if( fp )
-		    if( putc( c, fp ) == EOF ) {
+		  {
+		    if((count++)>opt.max_output)
+		      {
+			log_error("Error writing to `%s': %s\n",
+				  fname,"exceeded --max-output limit\n");
+			rc = G10ERR_WRITE_FILE;
+			goto leave;
+		      }
+		    else if( putc( c, fp ) == EOF )
+		      {
 			log_error("Error writing to `%s': %s\n",
 				  fname, strerror(errno) );
 			rc = G10ERR_WRITE_FILE;
@@ -238,8 +268,17 @@ handle_plaintext( PKT_plaintext *pt, md_filter_context_t *mfx,
 		    eof = 1;
 		if( mfx->md )
 		    md_write( mfx->md, buffer, len );
-		if( fp ) {
+		if( fp )
-		    if( fwrite( buffer, 1, len, fp ) != len ) {
+		  {
+		    if((count+=len)>opt.max_output)
+		      {
+			log_error("Error writing to `%s': %s\n",
+				  fname,"exceeded --max-output limit\n");
+			rc = G10ERR_WRITE_FILE;
+			m_free( buffer );
+			goto leave;
+		      }
+		    else if( fwrite( buffer, 1, len, fp ) != len ) {
 		      log_error("Error writing to `%s': %s\n",
 				fname, strerror(errno) );
 		      rc = G10ERR_WRITE_FILE;
@@ -256,8 +295,17 @@ handle_plaintext( PKT_plaintext *pt, md_filter_context_t *mfx,
 	int state = 0;
 
 	while( (c = iobuf_get(pt->buf)) != -1 ) {
-	    if( fp ) {
+	    if( fp )
-		if( putc( c, fp ) == EOF ) {
+	      {
+		if((count++)>opt.max_output)
+		  {
+		    log_error("Error writing to `%s': %s\n",
+			      fname,"exceeded --max-output limit\n");
+		    rc = G10ERR_WRITE_FILE;
+		    goto leave;
+		  }
+		else if( putc( c, fp ) == EOF )
+		  {
 		    log_error("Error writing to `%s': %s\n",
 			      fname, strerror(errno) );
 		    rc = G10ERR_WRITE_FILE;