From 812ef1eac7ff2b70310be859cc3250fa834a73ef Mon Sep 17 00:00:00 2001
From: Mirek Kratochvil <exa.exa@gmail.com>
Date: Sat, 25 Jan 2014 17:27:02 +0100
Subject: [PATCH] keyring: do backups and save some writes
---
src/keyring.cpp | 44 ++++++++++++++++++++++++++++++++++----------
src/keyring.h | 2 ++
2 files changed, 36 insertions(+), 10 deletions(-)
diff --git a/src/keyring.cpp b/src/keyring.cpp
index 5bb4ce8..bfdf69a 100644
--- a/src/keyring.cpp
+++ b/src/keyring.cpp
@@ -269,6 +269,8 @@ sencode* keyring::serialize_pubkeys (const pubkey_storage&pubs)
#define CCR_CONFDIR "/.ccr"
#endif
+#define BAK_SUFFIX "~"
+
#include <stdlib.h>
static std::string get_user_dir()
@@ -295,6 +297,7 @@ static std::string get_user_dir()
* We try to setup file permissions properly here and don't care about it later
* (so that the user can override the default value by easy unixy way)
*/
+
static bool ensure_empty_sencode_file (const std::string&fn,
const std::string&ident)
{
@@ -347,14 +350,19 @@ static bool prepare_user_dir (const std::string&dir)
if (!S_ISDIR (st.st_mode) )
return false;
- //finally create empty key storages, if not present
+ //finally create empty key storages and backups, if not present
return ensure_empty_sencode_file (dir + PUBKEYS_FILENAME,
PUBKEYS_ID) &&
+ ensure_empty_sencode_file (dir + PUBKEYS_FILENAME BAK_SUFFIX,
+ PUBKEYS_ID) &&
ensure_empty_sencode_file (dir + SECRETS_FILENAME,
+ KEYPAIRS_ID) &&
+ ensure_empty_sencode_file (dir + SECRETS_FILENAME BAK_SUFFIX,
KEYPAIRS_ID);
}
-static sencode* file_get_sencode (const std::string&fn)
+static sencode* file_get_sencode (const std::string&fn,
+ std::string&data)
{
//check whether it is a file first
struct stat st;
@@ -365,7 +373,6 @@ static sencode* file_get_sencode (const std::string&fn)
return NULL;
//not we got the size, prepare buffer space
- std::string data;
data.resize (st.st_size, 0);
std::ifstream in (fn.c_str(), std::ios::in | std::ios::binary);
@@ -377,10 +384,14 @@ static sencode* file_get_sencode (const std::string&fn)
return sencode_decode (data);
}
-static bool file_put_sencode (const std::string&fn, sencode*in)
+static sencode* file_get_sencode (const std::string&fn)
{
- std::string data = in->encode();
+ std::string data;
+ return file_get_sencode (fn, data);
+}
+static bool file_put_string (const std::string&fn, const std::string&data)
+{
std::ofstream out (fn.c_str(), std::ios::out | std::ios::binary);
if (!out) return false;
out.write (data.c_str(), data.length() );
@@ -391,6 +402,17 @@ static bool file_put_sencode (const std::string&fn, sencode*in)
return true;
}
+static bool file_put_sencode_with_backup (const std::string&fn, sencode*in,
+ const std::string&backup_fn,
+ const std::string&backup_data)
+{
+ std::string data = in->encode();
+ if (data == backup_data) return true; //nothing to do
+
+ return file_put_string (fn, data) &&
+ file_put_string (backup_fn, backup_data);
+}
+
#ifndef WIN32
#include <signal.h>
@@ -427,7 +449,7 @@ static void ignore_term_signals (bool ignore)
bool keyring::save()
{
- std::string dir, fn;
+ std::string dir, fn, bfn;
sencode*S;
bool res;
@@ -440,7 +462,8 @@ bool keyring::save()
*/
S = serialize_pubkeys (pubs);
fn = dir + PUBKEYS_FILENAME;
- res = file_put_sencode (fn, S);
+ bfn = fn + BAK_SUFFIX;
+ res = file_put_sencode_with_backup (fn, S, bfn, backup_pubs);
sencode_destroy (S);
if (!res) goto failure;
@@ -449,7 +472,8 @@ bool keyring::save()
*/
S = serialize_keypairs (pairs);
fn = dir + SECRETS_FILENAME;
- res = file_put_sencode (fn, S);
+ bfn = fn + BAK_SUFFIX;
+ res = file_put_sencode_with_backup (fn, S, bfn, backup_pairs);
sencode_destroy (S);
if (!res) goto failure;
@@ -488,7 +512,7 @@ bool keyring::open()
sencode *pubkeys, *keypairs;
bool res;
- pubkeys = file_get_sencode (fn);
+ pubkeys = file_get_sencode (fn, backup_pubs);
if (!pubkeys) goto close_and_fail;
res = parse_pubkeys (pubkeys, pubs);
@@ -498,7 +522,7 @@ bool keyring::open()
//load keypairs
fn = dir + SECRETS_FILENAME;
- keypairs = file_get_sencode (fn);
+ keypairs = file_get_sencode (fn, backup_pairs);
if (!keypairs) goto close_and_fail;
res = parse_keypairs (keypairs, pairs);
diff --git a/src/keyring.h b/src/keyring.h
index 62d7223..7853764 100644
--- a/src/keyring.h
+++ b/src/keyring.h
@@ -71,6 +71,8 @@ public:
pubkey_storage pubs;
keypair_storage pairs;
+ std::string backup_pubs, backup_pairs;
+
keyring() {
lockfd = -1;
}