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// Copyright (C) 2005 Timothy Brownawell <tbrownaw@gmail.com>
//
// This program is made available under the GNU GPL version 2.0 or
// greater. See the accompanying file COPYING for details.
//
// This program is distributed WITHOUT ANY WARRANTY; without even the
// implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
// PURPOSE.
#include "base.hh"
#include <sstream>
#include <botan/botan.h>
#include <botan/rsa.h>
#include <botan/pem.h>
#include <botan/look_pk.h>
#include "char_classifiers.hh"
#include "key_store.hh"
#include "file_io.hh"
#include "packet.hh"
#include "project.hh"
#include "database.hh"
#include "keys.hh"
#include "globish.hh"
#include "app_state.hh"
#include "transforms.hh"
#include "constants.hh"
#include "ssh_agent.hh"
#include "safe_map.hh"
#include "charset.hh"
#include "ui.hh"
#include "lazy_rng.hh"
#include "botan_pipe_cache.hh"
using std::make_pair;
using std::istringstream;
using std::map;
using std::ostringstream;
using std::pair;
using std::string;
using std::vector;
using boost::scoped_ptr;
using boost::shared_ptr;
using boost::shared_dynamic_cast;
using Botan::RSA_PrivateKey;
using Botan::RSA_PublicKey;
using Botan::SecureVector;
using Botan::X509_PublicKey;
using Botan::PKCS8_PrivateKey;
using Botan::PK_Decryptor;
using Botan::PK_Signer;
using Botan::Pipe;
using Botan::get_pk_decryptor;
using Botan::get_cipher;
typedef pair<key_name, keypair> key_info;
typedef pair<key_id, key_info> full_key_info;
typedef map<key_id, key_info> key_map;
struct key_store_state
{
system_path const key_dir;
string const ssh_sign_mode;
bool non_interactive;
bool have_read;
lua_hooks & lua;
key_map keys;
// These are used to cache keys and signers (if the hook allows).
map<key_id, shared_ptr<RSA_PrivateKey> > privkey_cache;
map<key_id, shared_ptr<PK_Signer> > signer_cache;
// Initialized when first required.
scoped_ptr<ssh_agent> agent;
key_store_state(app_state & app)
: key_dir(app.opts.key_dir), ssh_sign_mode(app.opts.ssh_sign),
non_interactive(app.opts.non_interactive),
have_read(false), lua(app.lua)
{
E(app.opts.key_dir_given
|| app.opts.conf_dir_given
|| !app.opts.no_default_confdir,
origin::user,
F("No available keystore found"));
}
// internal methods
void get_key_file(key_id const & ident, key_name const & name,
system_path & file);
void get_old_key_file(key_name const & name, system_path & file);
void write_key(full_key_info const & info);
void maybe_read_key_dir();
shared_ptr<RSA_PrivateKey> decrypt_private_key(key_id const & id,
bool force_from_user = false);
// just like put_key_pair except that the key is _not_ written to disk.
// for internal use in reading keys back from disk.
bool put_key_pair_memory(full_key_info const & info);
// wrapper around accesses to agent, initializes as needed
ssh_agent & get_agent()
{
if (!agent)
agent.reset(new ssh_agent);
return *agent;
}
// duplicates of key_store interfaces for use by key_store_state methods
// and the keyreader.
bool maybe_get_key_pair(key_id const & ident,
key_name & name,
keypair & kp);
bool put_key_pair(full_key_info const & info);
void migrate_old_key_pair(key_name const & id,
old_arc4_rsa_priv_key const & old_priv,
rsa_pub_key const & pub);
};
namespace
{
struct keyreader : public packet_consumer
{
key_store_state & kss;
keyreader(key_store_state & kss): kss(kss) {}
virtual void consume_file_data(file_id const & ident,
file_data const & dat)
{E(false, origin::system, F("Extraneous data in key store."));}
virtual void consume_file_delta(file_id const & id_old,
file_id const & id_new,
file_delta const & del)
{E(false, origin::system, F("Extraneous data in key store."));}
virtual void consume_revision_data(revision_id const & ident,
revision_data const & dat)
{E(false, origin::system, F("Extraneous data in key store."));}
virtual void consume_revision_cert(cert const & t)
{E(false, origin::system, F("Extraneous data in key store."));}
virtual void consume_public_key(key_name const & ident,
rsa_pub_key const & k)
{E(false, origin::system, F("Extraneous data in key store."));}
virtual void consume_key_pair(key_name const & name,
keypair const & kp)
{
L(FL("reading key pair '%s' from key store") % name);
key_id ident;
key_hash_code(name, kp.pub, ident);
E(kss.put_key_pair_memory(full_key_info(ident, key_info(name, kp))),
origin::system,
F("Key store has multiple copies of the key with id '%s'.") % ident);
L(FL("successfully read key pair '%s' from key store") % ident);
}
// for backward compatibility
virtual void consume_old_private_key(key_name const & ident,
old_arc4_rsa_priv_key const & k)
{
W(F("converting old-format private key '%s'") % ident);
rsa_pub_key dummy;
kss.migrate_old_key_pair(ident, k, dummy);
L(FL("successfully read key pair '%s' from key store") % ident);
}
};
}
key_store::key_store(app_state & a)
: s(new key_store_state(a))
{}
key_store::~key_store()
{}
bool
key_store::have_signing_key() const
{
return !signing_key.inner()().empty();
}
system_path const &
key_store::get_key_dir() const
{
return s->key_dir;
}
void
key_store_state::maybe_read_key_dir()
{
if (have_read)
return;
have_read = true;
if (!directory_exists(key_dir))
{
L(FL("key dir '%s' does not exist") % key_dir);
return;
}
L(FL("reading key dir '%s'") % key_dir);
vector<system_path> key_files;
fill_path_vec<system_path> fill_key_files(key_dir, key_files, false);
dirent_ignore ignore;
read_directory(key_dir, fill_key_files, ignore, ignore);
keyreader kr(*this);
for (vector<system_path>::const_iterator i = key_files.begin();
i != key_files.end(); ++i)
{
L(FL("reading keys from file '%s'") % (*i));
data dat;
read_data(*i, dat);
istringstream is(dat());
if (read_packets(is, kr) == 0)
W(F("ignored invalid key file ('%s') in key store") % (*i) );
}
}
void
key_store::get_key_ids(vector<key_id> & priv)
{
s->maybe_read_key_dir();
priv.clear();
for (key_map::const_iterator i = s->keys.begin(); i != s->keys.end(); ++i)
priv.push_back(i->first);
}
bool
key_store::key_pair_exists(key_id const & ident)
{
s->maybe_read_key_dir();
return s->keys.find(ident) != s->keys.end();
}
bool
key_store::key_pair_exists(key_name const & name)
{
s->maybe_read_key_dir();
for (key_map::const_iterator i = s->keys.begin();
i != s->keys.end(); ++i)
{
if (i->second.first == name)
return true;
}
return false;
}
bool
key_store_state::maybe_get_key_pair(key_id const & ident,
key_name & name,
keypair & kp)
{
maybe_read_key_dir();
key_map::const_iterator i = keys.find(ident);
if (i == keys.end())
return false;
name = i->second.first;
kp = i->second.second;
return true;
}
bool
key_store::maybe_get_key_pair(key_id const & ident,
keypair & kp)
{
key_name name;
return s->maybe_get_key_pair(ident, name, kp);
}
void
key_store::get_key_pair(key_id const & ident,
keypair & kp)
{
MM(ident);
bool found = maybe_get_key_pair(ident, kp);
I(found);
}
bool
key_store::maybe_get_key_pair(key_id const & hash,
key_name & keyid,
keypair & kp)
{
key_map::const_iterator ki = s->keys.find(hash);
if (ki == s->keys.end())
return false;
keyid = ki->second.first;
kp = ki->second.second;
return true;
}
void
key_store::get_key_pair(key_id const & hash,
key_name & keyid,
keypair & kp)
{
MM(hash);
bool found = maybe_get_key_pair(hash, keyid, kp);
I(found);
}
void
key_store_state::get_key_file(key_id const & ident,
key_name const & name,
system_path & file)
{
hexenc<id> encoded;
encode_hexenc(ident.inner(), encoded);
static const string allowed_special_chars("@%^_-+=.,;~[]");
string basename;
for (string::const_iterator iter = name().begin();
iter != name().end(); ++iter)
{
if (is_alnum(*iter) ||
is_space(*iter) ||
allowed_special_chars.find(*iter) != string::npos)
{
basename += *iter;
}
else
{
basename += '?';
}
}
file = key_dir / path_component(basename + "." + encoded(),
origin::internal);
}
void
key_store_state::get_old_key_file(key_name const & name,
system_path & file)
{
// filename is the keypair id, except that some characters can't be put in
// filenames (especially on windows).
string leaf = name();
for (unsigned int i = 0; i < leaf.size(); ++i)
if (leaf.at(i) == '+')
leaf.at(i) = '_';
file = key_dir / path_component(leaf, origin::internal);
}
void
key_store_state::write_key(full_key_info const & info)
{
ostringstream oss;
packet_writer pw(oss);
pw.consume_key_pair(info.second.first, info.second.second);
data dat(oss.str(), info.second.first.made_from);
system_path file;
get_key_file(info.first, info.second.first, file);
// Make sure the private key is not readable by anyone other than the user.
L(FL("writing key '%s' to file '%s' in dir '%s'")
% info.first % file % key_dir);
write_data_userprivate(file, dat, key_dir);
system_path old_file;
get_old_key_file(info.second.first, old_file);
if (file_exists(old_file))
delete_file(old_file);
}
bool
key_store_state::put_key_pair(full_key_info const & info)
{
maybe_read_key_dir();
bool newkey = put_key_pair_memory(info);
if (newkey)
write_key(info);
return newkey;
}
bool
key_store::put_key_pair(key_name const & name,
keypair const & kp)
{
key_id ident;
key_hash_code(name, kp.pub, ident);
return s->put_key_pair(full_key_info(ident, key_info(name, kp)));
}
bool
key_store_state::put_key_pair_memory(full_key_info const & info)
{
L(FL("putting key pair '%s'") % info.first);
pair<key_map::iterator, bool> res;
res = keys.insert(info);
if (!res.second)
{
L(FL("skipping existing key pair %s") % info.first);
return false;
}
return true;
}
void
key_store::delete_key(key_id const & ident)
{
s->maybe_read_key_dir();
key_map::iterator i = s->keys.find(ident);
if (i != s->keys.end())
{
system_path file;
s->get_key_file(ident, i->second.first, file);
delete_file(file);
s->keys.erase(i);
s->signer_cache.erase(ident);
s->privkey_cache.erase(ident);
}
}
//
// Crypto operations
//
// "raw" passphrase prompter; unaware of passphrase caching or the laziness
// hook. KEYID is used only in prompts. CONFIRM_PHRASE causes the user to
// be prompted to type the same thing twice, and will loop if they don't
// match. Prompts are worded slightly differently if GENERATING_KEY is true.
static void
get_passphrase(utf8 & phrase,
key_name const & keyname,
key_id const & keyid,
bool confirm_phrase,
bool generating_key)
{
string prompt1, prompt2;
char pass1[constants::maxpasswd];
char pass2[constants::maxpasswd];
int i = 0;
hexenc<id> hexid;
encode_hexenc(keyid.inner(), hexid);
string const short_id = hexid().substr(0, 8) + "...";
if (confirm_phrase && !generating_key)
prompt1 = (F("enter new passphrase for key ID [%s] (%s): ")
% keyname % short_id).str();
else
prompt1 = (F("enter passphrase for key ID [%s] (%s): ")
% keyname % short_id).str();
if (confirm_phrase)
prompt2 = (F("confirm passphrase for key ID [%s] (%s): ")
% keyname % short_id).str();
try
{
for (;;)
{
memset(pass1, 0, constants::maxpasswd);
memset(pass2, 0, constants::maxpasswd);
ui.ensure_clean_line();
read_password(prompt1, pass1, constants::maxpasswd);
if (!confirm_phrase)
break;
ui.ensure_clean_line();
read_password(prompt2, pass2, constants::maxpasswd);
if (strcmp(pass1, pass2) == 0)
break;
E(i++ < 2, origin::user, F("too many failed passphrases"));
P(F("passphrases do not match, try again"));
}
external ext_phrase(pass1);
system_to_utf8(ext_phrase, phrase);
}
catch (...)
{
memset(pass1, 0, constants::maxpasswd);
memset(pass2, 0, constants::maxpasswd);
throw;
}
memset(pass1, 0, constants::maxpasswd);
memset(pass2, 0, constants::maxpasswd);
}
shared_ptr<RSA_PrivateKey>
key_store_state::decrypt_private_key(key_id const & id,
bool force_from_user)
{
// See if we have this key in the decrypted key cache.
map<key_id, shared_ptr<RSA_PrivateKey> >::const_iterator
cpk = privkey_cache.find(id);
if (cpk != privkey_cache.end())
return cpk->second;
keypair kp;
key_name name;
E(maybe_get_key_pair(id, name, kp), origin::user,
F("no key pair '%s' found in key store '%s'") % id % key_dir);
L(FL("%d-byte private key") % kp.priv().size());
shared_ptr<PKCS8_PrivateKey> pkcs8_key;
try // with empty passphrase
{
Botan::DataSource_Memory ds(kp.priv());
#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,7,7)
pkcs8_key.reset(Botan::PKCS8::load_key(ds, lazy_rng::get(), ""));
#else
pkcs8_key.reset(Botan::PKCS8::load_key(ds, ""));
#endif
}
catch (Botan::Exception & e)
{
L(FL("failed to load key with no passphrase: %s") % e.what());
utf8 phrase;
string lua_phrase;
key_identity_info identity;
identity.id = id;
identity.given_name = name;
// See whether a lua hook will tell us the passphrase.
if ((!force_from_user || non_interactive) &&
lua.hook_get_passphrase(identity, lua_phrase))
{
phrase = utf8(lua_phrase, origin::user);
}
else if (!non_interactive)
{
get_passphrase(phrase, name, id, false, false);
}
int cycles = 0;
for (;;)
try
{
Botan::DataSource_Memory ds(kp.priv());
#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,7,7)
pkcs8_key.reset(Botan::PKCS8::load_key(ds, lazy_rng::get(), phrase()));
#else
pkcs8_key.reset(Botan::PKCS8::load_key(ds, phrase()));
#endif
break;
}
catch (Botan::Exception & e)
{
cycles++;
L(FL("decrypt_private_key: failure %d to load encrypted key: %s")
% cycles % e.what());
E(cycles < 3 && !non_interactive, origin::no_fault,
F("failed to decrypt old private RSA key, probably incorrect "
"passphrase or missing 'get_passphrase' lua hook"));
get_passphrase(phrase, name, id, false, false);
continue;
}
}
I(pkcs8_key);
shared_ptr<RSA_PrivateKey> priv_key;
priv_key = shared_dynamic_cast<RSA_PrivateKey>(pkcs8_key);
E(priv_key, origin::no_fault,
F("failed to extract RSA private key from PKCS#8 keypair"));
// Cache the decrypted key if we're allowed.
if (lua.hook_persist_phrase_ok())
safe_insert(privkey_cache, make_pair(id, priv_key));
return priv_key;
}
void
key_store::cache_decrypted_key(const key_id & id)
{
signing_key = id;
keypair key;
get_key_pair(id, key);
if (s->get_agent().has_key(key))
{
L(FL("ssh-agent has key '%s' loaded, skipping internal cache") % id);
return;
}
if (s->lua.hook_persist_phrase_ok())
s->decrypt_private_key(id);
}
void
key_store::create_key_pair(database & db,
key_name const & ident,
create_key_pair_mode create_mode,
utf8 const * maybe_passphrase,
key_id * const maybe_hash)
{
conditional_transaction_guard guard(db);
bool exists = false;
for (key_map::iterator i = s->keys.begin(); i != s->keys.end(); ++i)
{
if (i->second.first == ident)
exists = true;
}
E(!exists, origin::user, F("key '%s' already exists") % ident);
utf8 prompted_passphrase;
if (!maybe_passphrase)
{
get_passphrase(prompted_passphrase, ident, key_id(), true, true);
maybe_passphrase = &prompted_passphrase;
}
// okay, now we can create the key
if (create_mode == create_verbose)
{
P(F("generating key-pair '%s'") % ident);
}
else
{
L(FL("generating key-pair '%s'") % ident);
}
#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,7,7)
RSA_PrivateKey priv(lazy_rng::get(),
static_cast<Botan::u32bit>(constants::keylen));
#else
RSA_PrivateKey priv(static_cast<Botan::u32bit>(constants::keylen));
#endif
// serialize and maybe encrypt the private key
keypair kp;
SecureVector<Botan::byte> pubkey, privkey;
unfiltered_pipe->start_msg();
if ((*maybe_passphrase)().length())
Botan::PKCS8::encrypt_key(priv, *unfiltered_pipe,
#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,7,7)
lazy_rng::get(),
#endif
(*maybe_passphrase)(),
"PBE-PKCS5v20(SHA-1,TripleDES/CBC)",
Botan::RAW_BER);
else
Botan::PKCS8::encode(priv, *unfiltered_pipe);
unfiltered_pipe->end_msg();
kp.priv = rsa_priv_key(unfiltered_pipe->read_all_as_string(Pipe::LAST_MESSAGE),
origin::internal);
// serialize the public key
unfiltered_pipe->start_msg();
Botan::X509::encode(priv, *unfiltered_pipe, Botan::RAW_BER);
unfiltered_pipe->end_msg();
kp.pub = rsa_pub_key(unfiltered_pipe->read_all_as_string(Pipe::LAST_MESSAGE),
origin::internal);
// convert to storage format
L(FL("generated %d-byte public key\n"
"generated %d-byte (encrypted) private key\n")
% kp.pub().size()
% kp.priv().size());
// and save it.
if (create_mode == create_verbose)
{
P(F("storing key-pair '%s' in %s/") % ident % get_key_dir());
}
else
{
L(FL("storing key-pair '%s' in %s/") % ident % get_key_dir());
}
put_key_pair(ident, kp);
if (db.database_specified())
{
guard.acquire();
if (create_mode == create_verbose)
{
P(F("storing public key '%s' in %s") % ident % db.get_filename());
}
else
{
L(FL("storing public key '%s' in %s") % ident % db.get_filename());
}
db.put_key(ident, kp.pub);
guard.commit();
}
key_id hash;
key_hash_code(ident, kp.pub, hash);
if (maybe_hash)
*maybe_hash = hash;
if (create_mode == create_verbose)
{
P(F("key '%s' has hash '%s'") % ident % hash);
}
}
void
key_store::change_key_passphrase(key_id const & id)
{
key_name name;
keypair kp;
{
bool found = false;
s->maybe_read_key_dir();
key_map::const_iterator i = s->keys.find(id);
E(i != s->keys.end(), origin::user,
F("no key pair '%s' found in key store '%s'") % id % s->key_dir);
name = i->second.first;
kp = i->second.second;
}
shared_ptr<RSA_PrivateKey> priv = s->decrypt_private_key(id, true);
utf8 new_phrase;
get_passphrase(new_phrase, name, id, true, false);
unfiltered_pipe->start_msg();
if (new_phrase().length())
Botan::PKCS8::encrypt_key(*priv, *unfiltered_pipe,
#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,7,7)
lazy_rng::get(),
#endif
new_phrase(),
"PBE-PKCS5v20(SHA-1,TripleDES/CBC)",
Botan::RAW_BER);
else
Botan::PKCS8::encode(*priv, *unfiltered_pipe);
unfiltered_pipe->end_msg();
kp.priv = rsa_priv_key(unfiltered_pipe->read_all_as_string(Pipe::LAST_MESSAGE),
origin::internal);
delete_key(id);
put_key_pair(name, kp);
}
void
key_store::decrypt_rsa(key_id const & id,
rsa_oaep_sha_data const & ciphertext,
string & plaintext)
{
try
{
keypair kp;
load_key_pair(*this, id, kp);
shared_ptr<RSA_PrivateKey> priv_key = s->decrypt_private_key(id);
shared_ptr<PK_Decryptor>
decryptor(get_pk_decryptor(*priv_key, "EME1(SHA-1)"));
SecureVector<Botan::byte> plain =
decryptor->decrypt(reinterpret_cast<Botan::byte const *>(ciphertext().data()),
ciphertext().size());
plaintext = string(reinterpret_cast<char const*>(plain.begin()),
plain.size());
}
catch (Botan::Exception & ex)
{
E(false, ciphertext.made_from,
F("Botan error decrypting data: '%s'") % ex.what());
}
}
void
key_store::make_signature(database & db,
key_id const & id,
string const & tosign,
rsa_sha1_signature & signature)
{
key_name name;
keypair key;
get_key_pair(id, name, key);
// If the database doesn't have this public key, add it now.
if (!db.public_key_exists(id))
db.put_key(name, key.pub);
string sig_string;
ssh_agent & agent = s->get_agent();
//sign with ssh-agent (if connected)
E(agent.connected() || s->ssh_sign_mode != "only", origin::user,
F("You have chosen to sign only with ssh-agent but ssh-agent"
" does not seem to be running."));
if (s->ssh_sign_mode == "yes"
|| s->ssh_sign_mode == "check"
|| s->ssh_sign_mode == "only")
{
if (agent.connected()) {
//grab the monotone public key as an RSA_PublicKey
SecureVector<Botan::byte> pub_block;
pub_block.set(reinterpret_cast<Botan::byte const *>(key.pub().data()),
key.pub().size());
L(FL("make_signature: building %d-byte pub key") % pub_block.size());
shared_ptr<X509_PublicKey> x509_key =
shared_ptr<X509_PublicKey>(Botan::X509::load_key(pub_block));
shared_ptr<RSA_PublicKey> pub_key = shared_dynamic_cast<RSA_PublicKey>(x509_key);
if (!pub_key)
throw recoverable_failure(origin::system,
"Failed to get monotone RSA public key");
agent.sign_data(*pub_key, tosign, sig_string);
}
if (sig_string.length() <= 0)
L(FL("make_signature: monotone and ssh-agent keys do not match, will"
" use monotone signing"));
}
string ssh_sig = sig_string;
E(ssh_sig.length() > 0 || s->ssh_sign_mode != "only", origin::user,
F("You don't seem to have your monotone key imported "));
if (ssh_sig.length() <= 0
|| s->ssh_sign_mode == "check"
|| s->ssh_sign_mode == "no")
{
SecureVector<Botan::byte> sig;
// we permit the user to relax security here, by caching a decrypted key
// (if they permit it) through the life of a program run. this helps when
// you're making a half-dozen certs during a commit or merge or
// something.
bool persist_phrase = (!s->signer_cache.empty()
|| s->lua.hook_persist_phrase_ok());
shared_ptr<PK_Signer> signer;
shared_ptr<RSA_PrivateKey> priv_key;
if (persist_phrase && s->signer_cache.find(id) != s->signer_cache.end())
signer = s->signer_cache[id];
else
{
priv_key = s->decrypt_private_key(id);
if (agent.connected()
&& s->ssh_sign_mode != "only"
&& s->ssh_sign_mode != "no") {
L(FL("make_signature: adding private key (%s) to ssh-agent") % id);
agent.add_identity(*priv_key, name());
}
signer = shared_ptr<PK_Signer>(get_pk_signer(*priv_key, "EMSA3(SHA-1)"));
/* If persist_phrase is true, the RSA_PrivateKey object is
cached in s->active_keys and will survive as long as the
PK_Signer object does. */
if (persist_phrase)
s->signer_cache.insert(make_pair(id, signer));
}
#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,7,7)
sig = signer->sign_message(
reinterpret_cast<Botan::byte const *>(tosign.data()),
tosign.size(), lazy_rng::get());
#else
sig = signer->sign_message(
reinterpret_cast<Botan::byte const *>(tosign.data()),
tosign.size());
#endif
sig_string = string(reinterpret_cast<char const*>(sig.begin()), sig.size());
}
if (s->ssh_sign_mode == "check" && ssh_sig.length() > 0)
{
E(ssh_sig == sig_string, origin::system,
F("make_signature: ssh signature (%i) != monotone signature (%i)\n"
"ssh signature : %s\n"
"monotone signature: %s")
% ssh_sig.length()
% sig_string.length()
% ssh_sig
% sig_string);
L(FL("make_signature: signatures from ssh-agent and monotone"
" are the same"));
}
L(FL("make_signature: produced %d-byte signature") % sig_string.size());
signature = rsa_sha1_signature(sig_string, origin::internal);
cert_status s = db.check_signature(id, tosign, signature);
I(s != cert_unknown);
E(s == cert_ok, origin::system, F("make_signature: signature is not valid"));
}
//
// Interoperation with ssh-agent (see also above)
//
void
key_store::add_key_to_agent(key_id const & id)
{
ssh_agent & agent = s->get_agent();
E(agent.connected(), origin::user,
F("no ssh-agent is available, cannot add key '%s'") % id);
shared_ptr<RSA_PrivateKey> priv = s->decrypt_private_key(id);
key_name name;
keypair kp;
s->maybe_get_key_pair(id, name, kp);
agent.add_identity(*priv, name());
}
void
key_store::export_key_for_agent(key_id const & id,
std::ostream & os)
{
shared_ptr<RSA_PrivateKey> priv = s->decrypt_private_key(id);
key_name name;
{
keypair kp;
I(s->maybe_get_key_pair(id, name, kp));
}
utf8 new_phrase;
get_passphrase(new_phrase, name, id, true, false);
// This pipe cannot sensibly be recycled.
Pipe p(new Botan::DataSink_Stream(os));
p.start_msg();
if (new_phrase().length())
Botan::PKCS8::encrypt_key(*priv,
p,
#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,7,7)
lazy_rng::get(),
#endif
new_phrase(),
"PBE-PKCS5v20(SHA-1,TripleDES/CBC)");
else
Botan::PKCS8::encode(*priv, p);
p.end_msg();
}
//
// Migration from old databases
//
void
key_store_state::migrate_old_key_pair
(key_name const & id,
old_arc4_rsa_priv_key const & old_priv,
rsa_pub_key const & pub)
{
keypair kp;
SecureVector<Botan::byte> arc4_key;
utf8 phrase;
shared_ptr<PKCS8_PrivateKey> pkcs8_key;
shared_ptr<RSA_PrivateKey> priv_key;
// See whether a lua hook will tell us the passphrase.
key_identity_info identity;
identity.given_name = id;
string lua_phrase;
if (lua.hook_get_passphrase(identity, lua_phrase))
phrase = utf8(lua_phrase, origin::user);
else
get_passphrase(phrase, id, key_id(), false, false);
int cycles = 1;
for (;;)
try
{
arc4_key.set(reinterpret_cast<Botan::byte const *>(phrase().data()),
phrase().size());
Pipe arc4_decryptor(get_cipher("ARC4", arc4_key, Botan::DECRYPTION));
arc4_decryptor.process_msg(old_priv());
// This is necessary because PKCS8::load_key() cannot currently
// recognize an unencrypted, raw-BER blob as such, but gets it
// right if it's PEM-coded.
SecureVector<Botan::byte> arc4_decrypt(arc4_decryptor.read_all());
Botan::DataSource_Memory ds(Botan::PEM_Code::encode(arc4_decrypt,
"PRIVATE KEY"));
#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,7,7)
pkcs8_key.reset(Botan::PKCS8::load_key(ds, lazy_rng::get()));
#else
pkcs8_key.reset(Botan::PKCS8::load_key(ds));
#endif
break;
}
catch (Botan::Exception & e)
{
L(FL("migrate_old_key_pair: failure %d to load old private key: %s")
% cycles % e.what());
E(cycles <= 3, origin::no_fault,
F("failed to decrypt old private RSA key, "
"probably incorrect passphrase"));
get_passphrase(phrase, id, key_id(), false, false);
cycles++;
continue;
}
priv_key = shared_dynamic_cast<RSA_PrivateKey>(pkcs8_key);
I(priv_key);
// now we can write out the new key
unfiltered_pipe->start_msg();
Botan::PKCS8::encrypt_key(*priv_key, *unfiltered_pipe,
#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,7,7)
lazy_rng::get(),
#endif
phrase(),
"PBE-PKCS5v20(SHA-1,TripleDES/CBC)",
Botan::RAW_BER);
unfiltered_pipe->end_msg();
kp.priv = rsa_priv_key(unfiltered_pipe->read_all_as_string(Pipe::LAST_MESSAGE),
origin::internal);
// also the public key (which is derivable from the private key; asking
// Botan for the X.509 encoding of the private key implies that we want
// it to derive and produce the public key)
unfiltered_pipe->start_msg();
Botan::X509::encode(*priv_key, *unfiltered_pipe, Botan::RAW_BER);
unfiltered_pipe->end_msg();
kp.pub = rsa_pub_key(unfiltered_pipe->read_all_as_string(Pipe::LAST_MESSAGE),
origin::internal);
// if the database had a public key entry for this key, make sure it
// matches what we derived from the private key entry, but don't abort the
// whole migration if it doesn't.
if (!pub().empty() && !keys_match(id, pub, id, kp.pub))
W(F("public and private keys for %s don't match") % id);
key_id hash;
key_hash_code(id, kp.pub, hash);
put_key_pair(full_key_info(hash, key_info(id, kp)));
}
void
key_store::migrate_old_key_pair
(key_name const & id,
old_arc4_rsa_priv_key const & old_priv,
rsa_pub_key const & pub)
{
s->migrate_old_key_pair(id, old_priv, pub);
}
// Local Variables:
// mode: C++
// fill-column: 76
// c-file-style: "gnu"
// indent-tabs-mode: nil
// End:
// vim: et:sw=2:sts=2:ts=2:cino=>2s,{s,\:s,+s,t0,g0,^-2,e-2,n-2,p2s,(0,=s:
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