From bbd4ef1cd1f0fb2f2c7b9cab3abbff052d04716f Mon Sep 17 00:00:00 2001
From: Nick Mathewson <nickm@torproject.org>
Date: Tue, 1 May 2007 01:10:50 +0000
Subject: [PATCH]  r12605@catbus:  nickm | 2007-04-30 21:10:48 -0400  Add an
 expiry date to key certificates.

svn:r10079
---
 doc/spec/proposals/103-multilevel-keys.txt |  1 +
 src/tools/tor-gencert.c                    | 22 +++++++++++++++++++++-
 2 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/doc/spec/proposals/103-multilevel-keys.txt b/doc/spec/proposals/103-multilevel-keys.txt
index 39814b80da..ce4da1fee8 100644
--- a/doc/spec/proposals/103-multilevel-keys.txt
+++ b/doc/spec/proposals/103-multilevel-keys.txt
@@ -118,6 +118,7 @@ Extensions to Proposal 101.
     "dir-identity-key": The long-term identity key for this authority.
     "dir-key-published": The time when this directory's signing key was
          last changed.
+    "dir-key-expires": A time after which this key is no longer valid.
     "dir-signing-key": As in proposal 101.
     "dir-key-certification": A signature of the above fields, in order.
          The signed material extends from the beginning of
diff --git a/src/tools/tor-gencert.c b/src/tools/tor-gencert.c
index 617557dc8c..fadefc13dd 100644
--- a/src/tools/tor-gencert.c
+++ b/src/tools/tor-gencert.c
@@ -29,12 +29,14 @@
 
 #define IDENTITY_KEY_BITS 3072
 #define SIGNING_KEY_BITS 1024
+#define DEFAULT_LIFETIME 12
 
 char *identity_key_file = NULL;
 char *signing_key_file = NULL;
 char *certificate_file = NULL;
 int verbose = 0;
 int make_new_id = 0;
+int months_lifetime = DEFAULT_LIFETIME;
 
 EVP_PKEY *identity_key = NULL;
 EVP_PKEY *signing_key = NULL;
@@ -92,6 +94,16 @@ parse_commandline(int argc, char **argv)
         return 1;
       }
       certificate_file = tor_strdup(argv[++i]);
+    } else if (!strcmp(argv[i], "-m")) {
+      if (i+1>=argc) {
+        fprintf(stderr, "No argument to -m\n");
+        return 1;
+      }
+      months_lifetime = atoi(argv[++i]);
+      if (months_lifetime > 24 || months_lifetime < 0) {
+        fprintf(stderr, "Lifetime (in months) was out of range.");
+        return 1;
+      }
     } else if (!strcmp(argv[i], "-v")) {
       verbose = 1;
     } else if (!strcmp(argv[i], "--create-identity-key")) {
@@ -275,7 +287,9 @@ generate_certificate(void)
 {
   char buf[8192];
   time_t now = time(NULL);
+  struct tm tm;
   char published[ISO_TIME_LEN+1];
+  char expires[ISO_TIME_LEN+1];
   char fingerprint[FINGERPRINT_LEN+1];
   char *ident = key_to_string(identity_key);
   char *signing = key_to_string(signing_key);
@@ -286,16 +300,22 @@ generate_certificate(void)
   int r;
 
   get_fingerprint(identity_key, fingerprint);
+
+  tor_localtime_r(&now, &tm);
+  tm.tm_mon += months_lifetime;
+
   format_iso_time(published, now);
+  format_iso_time(expires, mktime(&tm));
 
   tor_snprintf(buf, sizeof(buf),
                "dir-key-certificate-version 3\n"
                "fingerprint %s\n"
                "dir-key-published %s\n"
+               "dir-key-expires %s\n"
                "dir-identity-key\n%s"
                "dir-signing-key\n%s"
                "dir-key-certification\n",
-               fingerprint, published, ident, signing);
+               fingerprint, published, expires, ident, signing);
   signed_len = strlen(buf);
   SHA1((const unsigned char*)buf,signed_len,(unsigned char*)digest);