Re: [PATCH iptables 1/2] xtables-translate: add escape_quotes option to comment_xlate

[Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>]

On Tue, Aug 16, 2016 at 07:44:32PM +0200, Pablo M. Bermudo Garay wrote:
> The comment_xlate function was not supporting this option that is
> necessary in some situations.

I have applied what I'm attaching to this email, that is more simple
than this and makes sure buffer is nul-terminated (given snprintf
doesn't guarantee this).

commit 3317b14f0d6fa0e460e4e758b7e3010f940d07bc
Author: Pablo M. Bermudo Garay <pablombg@xxxxxxxxx>
Date:   Tue Aug 16 19:44:32 2016 +0200

    xtables-translate: add escape_quotes option to comment_xlate
    
    The comment_xlate function was not supporting this option that is
    necessary in some situations.
    
    Signed-off-by: Pablo M. Bermudo Garay <pablombg@xxxxxxxxx>
    Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>

diff --git a/extensions/libxt_comment.c b/extensions/libxt_comment.c
index 0e31edd..b635d16 100644
--- a/extensions/libxt_comment.c
+++ b/extensions/libxt_comment.c
@@ -52,9 +52,18 @@ static int comment_xlate(struct xt_xlate *xl,
 			 const struct xt_xlate_mt_params *params)
 {
 	struct xt_comment_info *commentinfo = (void *)params->match->data;
+	char comment[XT_MAX_COMMENT_LEN];
 
 	commentinfo->comment[XT_MAX_COMMENT_LEN - 1] = '\0';
-	xt_xlate_add_comment(xl, commentinfo->comment);
+	if (params->escape_quotes)
+		snprintf(comment, XT_MAX_COMMENT_LEN, "\\\"%s\\\"",
+			 commentinfo->comment);
+	else
+		snprintf(comment, XT_MAX_COMMENT_LEN, "\"%s\"",
+			 commentinfo->comment);
+
+	comment[XT_MAX_COMMENT_LEN - 1] = '\0';
+	xt_xlate_add_comment(xl, comment);
 
 	return 1;
 }