added c++ signature support

bindings/cpp/sign.cpp

@@ -0,0 +1,158 @@
+/*
+    This file is part of Pretty Curved Privacy (pcp1).
+
+    Copyright (C) 2013 T.Linden.
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+    You can contact me by mail: <tlinden AT cpan DOT org>.
+*/
+
+#include "sign++.h"
+
+using namespace std;
+using namespace pcp;
+
+Signature::Signature(Key &skey) {
+  S = skey;
+  havevault = false;
+  sig = NULL;
+}
+
+Signature::Signature(PubKey &pkey) {
+  P = pkey;
+  havevault = false;
+  sig = NULL;
+}
+
+Signature::Signature(Key &skey, PubKey &pkey) {
+  P = pkey;
+  S = skey;
+  havevault = false;
+  sig = NULL;
+}
+
+Signature::Signature(Vault &v) {
+  vault = v;
+  havevault = true;
+  sig = NULL;
+  S = vault.get_primary();
+}
+
+Signature::~Signature() {
+  if(sig != NULL)
+    free(sig);
+}
+
+std::string Signature::sign(std::vector<unsigned char> message) {
+  unsigned char *m = (unsigned char *)ucmalloc(message.size());
+  for(size_t i=0; i<message.size(); ++i)
+    m[i] = message[i];
+  string _s = Signature::sign(m, message.size());
+  free(m);
+  return _s;
+}
+
+std::string Signature::sign(std::string message) {
+  unsigned char *m = (unsigned char *)ucmalloc(message.size() + 1);
+  memcpy(m, message.c_str(), message.size());
+  string _s = Signature::sign(m, message.size() + 1);
+  free(m);
+  return _s;
+}
+
+std::string Signature::sign(unsigned char *message, size_t mlen) {
+  if(! S)
+    throw exception("Error: cannot sign without a secret key, use another constructor.");
+
+  if(S.is_encrypted())
+    throw exception("Error: cannot sign with an encrypted secret key, decrypt it before using.");
+
+  size_t zlen;
+  sig = pcp_ed_sign(message, mlen, S.K);
+
+  if(sig == NULL)
+    throw exception();
+
+  sig2be(sig);
+  char *encoded = pcp_z85_encode((unsigned char *)sig, sizeof(pcp_sig_t), &zlen);
+  sig2native(sig);
+
+  if(encoded == NULL)
+    throw exception();
+ 
+  // FIXME: who free()s encoced?
+  return string((char *)encoded);
+}
+
+bool Signature::verify(string signature, vector<unsigned char> message) {
+  unsigned char *m = (unsigned char *)ucmalloc(message.size());
+  for(size_t i=0; i<message.size(); ++i)
+    m[i] = message[i];
+  bool _b = Signature::verify(signature, m, message.size());
+  free(m);
+  return _b;
+}
+
+bool Signature::verify(string signature, string message) {
+  unsigned char *m = (unsigned char *)ucmalloc(message.size() + 1);
+  memcpy(m, message.c_str(), message.size());
+  bool _b = Signature::verify(signature, m, message.size() + 1);
+  free(m);
+  return _b;
+}
+
+bool Signature::verify(string signature, unsigned char *message, size_t mlen) {
+  size_t clen;
+  unsigned char *decoded = pcp_z85_decode((char *)signature.c_str(), &clen);
+
+  if(decoded == NULL)
+    throw exception();
+
+  if(clen != sizeof(pcp_sig_t)) {
+    free(decoded);
+    throw exception("Error: decoded signature didn't result to a proper sized sig!");
+  }
+
+  sig = (pcp_sig_t *)decoded;
+  sig2native(sig);
+
+  string sigid = string((char *)sig->id);
+
+  if(!P) {
+    if(havevault) {
+      if(vault.pubkey_exists(sigid)) {
+	P = vault.get_public(sigid);
+      }
+      else {
+	throw exception("Unable to verify, signed using an unknown key.");
+      }
+    }
+    else {
+      throw exception("No public key and no vault specified, unable to verify.");
+    }
+  }
+  else {
+    if(P.get_id() != sigid) {
+      throw exception("Specified public key doesn't match the signers key.");
+    }
+  }
+
+  if(pcp_ed_verify(message, mlen, sig, P.K) == 0) {
+    return true;
+  }
+  else {
+    throw exception();
+  }
+}