62/118: Be more strict about file names in NARs

[Ludovic Courtès]

civodul pushed a commit to branch nix
in repository guix.

commit 985f1595fe9f61095c7bc94b49be1179811ec630
Author: Eelco Dolstra <address@hidden>
Date:   Wed Jul 16 16:30:50 2014 +0200

    Be more strict about file names in NARs
---
 src/libutil/archive.cc |    7 ++++++-
 1 files changed, 6 insertions(+), 1 deletions(-)

diff --git a/src/libutil/archive.cc b/src/libutil/archive.cc
index dfe9653..9dc2ebe 100644
--- a/src/libutil/archive.cc
+++ b/src/libutil/archive.cc
@@ -231,7 +231,7 @@ static void parse(ParseSink & sink, Source & source, const 
Path & path)
         }
 
         else if (s == "entry" && type == tpDirectory) {
-            string name;
+            string name, prevName;
 
             s = readString(source);
             if (s != "(") throw badArchive("expected open tag");
@@ -245,6 +245,11 @@ static void parse(ParseSink & sink, Source & source, const 
Path & path)
                     break;
                 } else if (s == "name") {
                     name = readString(source);
+                    if (name.empty() || name == "." || name == ".." || 
name.find('/') != string::npos || name.find((char) 0) != string::npos)
+                        throw Error(format("NAR contains invalid file name 
`%1%'") % name);
+                    if (name <= prevName)
+                        throw Error("NAR directory is not sorted");
+                    prevName = name;
                     if (useCaseHack) {
                         auto i = names.find(name);
                         if (i != names.end()) {