+++ /dev/null
-/* fides.c - Light-weight, decentralised trust and authorisation management
- Copyright (C) 2008-2009 Guus Sliepen <guus@tinc-vpn.org>
-
- Fides is free software; you can redistribute it and/or modify
- it under the terms of the GNU Lesser General Public License as
- published by the Free Software Foundation; either version 2.1 of
- the License, or (at your option) any later version.
-
- Fides 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 Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public
- License along with this program; if not, see <http://www.gnu.org/licenses/>.
-*/
-
-#include <cstdio>
-#include <cstring>
-#include <cstdlib>
-#include <stdint.h>
-#include <getopt.h>
-#include <sysexits.h>
-#include <iostream>
-#include <fstream>
-#include <botan/types.h>
-#include <botan/botan.h>
-#include <botan/ecdsa.h>
-#include <botan/look_pk.h>
-#include <botan/lookup.h>
-#include <botan/filters.h>
-#include <botan/sha2_32.h>
-#include <sys/stat.h>
-#include <sys/types.h>
-#include <dirent.h>
-#include <list>
-
-#include "fides.h"
-
-using namespace std;
-
-// Global state
-
-Botan::LibraryInitializer libinit;
-Botan::AutoSeeded_RNG fides::rng;
-
-// Public key functions
-
-fides::publickey::publickey(): pub(0), trust(0) {
-}
-
-fides::publickey::~publickey() {
- delete pub;
-}
-
-void fides::publickey::load(istream &in) {
- try {
- Botan::DataSource_Stream source(in);
- pub = dynamic_cast<Botan::ECDSA_PublicKey *>(Botan::X509::load_key(source));
- } catch(Botan::Exception &e) {
- throw exception(e.what());
- }
-}
-
-void fides::publickey::load(const std::string &filename) {
- ifstream in(filename.c_str());
- load(in);
-}
-
-void fides::publickey::save(ostream &out) {
- out << to_string();
-}
-
-void fides::publickey::save(const std::string &filename) {
- ofstream out(filename.c_str());
- save(out);
-}
-
-void fides::publickey::from_string(const std::string &in) {
- try {
- Botan::DataSource_Memory source(in);
- pub = dynamic_cast<Botan::ECDSA_PublicKey *>(Botan::X509::load_key(source));
- } catch(Botan::Exception &e) {
- throw exception(e.what());
- }
-}
-
-string fides::publickey::to_string() {
- return Botan::X509::PEM_encode(*pub);
-}
-
-string fides::publickey::fingerprint(unsigned int bits) {
- // TODO: find out if there is a standard way to get a hash of an ECDSA public key
- Botan::SHA_256 sha256;
- Botan::SecureVector<Botan::byte> hash = sha256.process(Botan::X509::PEM_encode(*pub));
- return string((const char *)hash.begin(), bits / 8);
-}
-
-bool fides::publickey::verify(const std::string &statement, const std::string &signature) {
- auto_ptr<Botan::PK_Verifier> verifier(Botan::get_pk_verifier(*pub, "EMSA1(SHA-512)"));
- verifier->update((const Botan::byte *)statement.data(), statement.size());
- Botan::SecureVector<Botan::byte> sig;
- sig.set((const Botan::byte *)signature.data(), signature.size());
- return verifier->check_signature(sig);
-}
-
-// Private key functions
-
-fides::privatekey::privatekey(): priv(0) {
-}
-
-fides::privatekey::~privatekey() {
- delete priv;
- pub = 0;
-}
-
-void fides::privatekey::generate(const std::string &field) {
- Botan::EC_Domain_Params domain = Botan::get_EC_Dom_Pars_by_oid(field);
- pub = priv = new Botan::ECDSA_PrivateKey(rng, domain);
-}
-
-void fides::privatekey::generate(unsigned int bits) {
- switch(bits) {
- case 112: return generate("1.3.132.0.6");
- case 128: return generate("1.3.132.0.28");
- case 160: return generate("1.3.132.0.9");
- case 192: return generate("1.3.132.0.31");
- case 224: return generate("1.3.132.0.32");
- case 256: return generate("1.3.132.0.10");
- case 384: return generate("1.3.132.0.34");
- case 521: return generate("1.3.132.0.35");
- default: throw exception("Unsupported number of bits for private key");
- }
-}
-
-void fides::privatekey::load_private(istream &in) {
- try {
- Botan::DataSource_Stream stream(in);
- pub = priv = dynamic_cast<Botan::ECDSA_PrivateKey *>(Botan::PKCS8::load_key(stream, rng, ""));
- } catch(Botan::Exception &e) {
- throw exception(e.what());
- }
-}
-
-void fides::privatekey::load_private(const std::string &filename) {
- ifstream in(filename.c_str());
- load_private(in);
-}
-
-void fides::privatekey::save_private(ostream &out) {
- out << Botan::PKCS8::PEM_encode(*priv);
-}
-
-void fides::privatekey::save_private(const std::string &filename) {
- ofstream out(filename.c_str());
- save_private(out);
-}
-
-string fides::privatekey::sign(const std::string &statement) {
- auto_ptr<Botan::PK_Signer> signer(Botan::get_pk_signer(*priv, "EMSA1(SHA-512)"));
- Botan::SecureVector<Botan::byte> sig = signer->sign_message((const Botan::byte *)statement.data(), statement.size(), rng);
- return string((const char *)sig.begin(), (size_t)sig.size());
-}
-
-// Base64 and hex encoding/decoding functions
-
-string fides::hexencode(const string &in) {
- Botan::Pipe pipe(new Botan::Hex_Encoder);
- pipe.process_msg((Botan::byte *)in.data(), in.size());
- return pipe.read_all_as_string();
-}
-
-string fides::hexdecode(const string &in) {
- Botan::Pipe pipe(new Botan::Hex_Decoder);
- pipe.process_msg((Botan::byte *)in.data(), in.size());
- return pipe.read_all_as_string();
-}
-
-string fides::b64encode(const string &in) {
- Botan::Pipe pipe(new Botan::Base64_Encoder);
- pipe.process_msg((Botan::byte *)in.data(), in.size());
- return pipe.read_all_as_string();
-}
-
-string fides::b64decode(const string &in) {
- Botan::Pipe pipe(new Botan::Base64_Decoder);
- pipe.process_msg((Botan::byte *)in.data(), in.size());
- return pipe.read_all_as_string();
-}
-
-// Certificate functions
-
-fides::certificate::certificate(publickey *key, struct timeval timestamp, const std::string &statement, const std::string &signature): signer(key), timestamp(timestamp), statement(statement), signature(signature) {}
-
-bool fides::certificate::validate() {
- string data = signer->fingerprint(256);
- data += string((const char *)×tamp, sizeof timestamp);
- data += statement;
- return signer->verify(data, signature);
-}
-
-fides::certificate::certificate(privatekey *key, struct timeval timestamp, const std::string &statement): signer(key), timestamp(timestamp), statement(statement) {
- string data = signer->fingerprint(256);
- data += string((const char *)×tamp, sizeof timestamp);
- data += statement;
- signature = key->sign(data);
-}
-
-string fides::certificate::fingerprint(unsigned int bits) {
- return signature.substr(signature.size() - bits / 8);
-}
-
-string fides::certificate::to_string() const {
- string data = fides::hexencode(signer->fingerprint());
- data += ' ';
- char ts[100];
- snprintf(ts, sizeof ts, "%lu.%06lu", timestamp.tv_sec, timestamp.tv_usec);
- data += ts;
- data += ' ';
- data += fides::b64encode(signature);
- data += ' ';
- data += statement;
- return data;
-}
-
-static void help(ostream &out, const string &argv0) {
- out << "Usage: " << argv0 << "<command> [arguments]\n"
- "\n"
- "Available commands are:\n"
- "\n"
- " init Initialise fides, generate a public/private keypair.\n"
- " version Show version and copyright information.\n"
- " help Show this help message.\n"
- "\n"
- " trust <keyid>\n"
- " Trust allow/deny packets signed by the specified key.\n"
- " distrust <keyid>\n"
- " Distrust allow/deny packets signed by the specified key.\n"
- " dctrust <keyid>\n"
- " Don't care about allow/deny packets signed by the specified key.\n"
- " is_trusted <keyid>\n"
- " Returns 0 if key is trusted, 1 otherwise\n"
- " is_distrusted <keyid>\n"
- " Returns 0 if key is distrusted, 1 otherwise\n"
- "\n"
- " sign <stuff ...>\n"
- " Sign stuff.\n"
- " allow <stuff ...>\n"
- " Allow stuff.\n"
- " deny <stuff ...> \n"
- " Deny stuff.\n"
- " dontcare <stuff ...> \n"
- " Don't care about stuff.\n"
- " is_allowed <stuff ...>\n"
- " Returns 0 if stuff is allowed, 1 otherwise\n"
- " is_denied <stuff ...>\n"
- " Returns 0 if stuff is denied, 1 otherwise\n"
- "\n"
- " import [filename]\n"
- " Import keys and certificates from file, or stdin if unspecified.\n"
- " export [filename]\n"
- " Export keys and certificates to file, or stdout if unspecified.\n"
- " test <stuff ...>\n"
- " Tell whether stuff is allowed or not by counting relevant certificates\n"
- " find <regexp>\n"
- " Find all certificates matching regexp\n"
- " fsck Verify the signature on all information collected.\n";
-}
-
-static void version(ostream &out = cout) {
- out << "fides version 0.1\n"
- "Copyright (c) 2008-2009 Guus Sliepen <guus@tinc-vpn.org>\n"
- "\n"
- "This program is free software; you can redistribute it and/or modify\n"
- "it under the terms of the GNU General Public License as published by\n"
- "the Free Software Foundation; either version 2 of the License, or\n"
- "(at your option) any later version.\n";
-}
-
-// Utility functions
-
-static vector<string> dirlist(const string &path) {
- vector<string> files;
-
- DIR *dir = opendir(path.c_str());
- if(!dir)
- return files;
-
- struct dirent entry, *result = &entry;
-
- while(result) {
- readdir_r(dir, &entry, &result);
- if(!result)
- break;
- struct stat st;
- if(result->d_type == DT_UNKNOWN) {
- if(stat((path + "/" + result->d_name).c_str(), &st))
- continue;
- if(S_ISREG(st.st_mode))
- files.push_back(result->d_name);
- } else if(result->d_type == DT_REG) {
- files.push_back(result->d_name);
- }
- }
-
- closedir(dir);
-
- return files;
-}
-
-void fides::certificate_save(const certificate *cert, const string &filename) {
- ofstream file(filename.c_str());
- file << cert->to_string() << '\n';
-}
-
-fides::certificate *fides::certificate_load(const string &filename) {
- ifstream file(filename.c_str());
- string data;
- getline(file, data);
- return certificate_from_string(data);
-}
-
-fides::certificate *fides::certificate_from_string(const string &data) {
- size_t b, e;
- e = data.find(' ', 0);
- if(e == string::npos)
- throw exception("Invalid certificate");
- string fingerprint = hexdecode(data.substr(0, e));
- publickey *signer = find_key(fingerprint);
- if(!signer)
- throw exception("Unknown public key");
- b = e + 1;
- e = data.find('.', b);
- if(e == string::npos)
- throw exception("Invalid certificate");
- struct timeval timestamp;
- timestamp.tv_sec = atol(data.c_str() + b);
- b = e + 1;
- timestamp.tv_usec = atol(data.c_str() + b);
- e = data.find(' ', b);
- if(e == string::npos)
- throw exception("Invalid certificate");
- b = e + 1;
- e = data.find(' ', b);
- if(e == string::npos)
- throw exception("Invalid certificate");
- string signature = fides::b64decode(data.substr(b, e - b));
- b = e + 1;
- string statement = data.substr(b);
-
- return new certificate(signer, timestamp, statement, signature);
-}
-
-// Fides main functions
-
-fides::fides(const string &dir): homedir(dir) {
- cerr << "Fides initialising\n";
-
- // Set homedir to provided directory, or $FIDES_HOME, or $HOME/.fides, or as a last resort $PWD/.fides
- if(homedir.empty())
- homedir = getenv("FIDES_HOME") ?: "";
- if(homedir.empty()) {
- char cwd[PATH_MAX];
- homedir = getenv("HOME") ?: getcwd(cwd, sizeof cwd);
- homedir += "/.fides";
- }
-
- // Derived directories
- homedir += '/';
- certdir = homedir + "certs/";
- keydir = homedir + "keys/";
- obsoletedir = homedir + ".obsolete_certs/";
-
- // Ensure the homedir and its subdirectories exist
- mkdir(homedir.c_str(), 0700);
- mkdir(certdir.c_str(), 0700);
- mkdir(keydir.c_str(), 0700);
- mkdir(obsoletedir.c_str(), 0700);
-
- try {
- mykey.load_private(homedir + "priv");
- firstrun = false;
- } catch(fides::exception &e) {
- cerr << "Fides generating keypair\n";
- mykey.generate();
- mykey.save_private(homedir + "priv");
- mykey.save(keydir + hexencode(mykey.fingerprint()));
- firstrun = true;
- }
- vector<string> files = dirlist(keydir);
- for(size_t i = 0; i < files.size(); ++i) {
- cerr << "Loading key " << files[i] << '\n';
-
- publickey *key = new publickey();
- key->load(keydir + files[i]);
- keys[hexdecode(files[i])] = key;
- }
-
- keys[mykey.fingerprint()] = &mykey;
-
- files = dirlist(certdir);
- for(size_t i = 0; i < files.size(); ++i) {
- cerr << "Loading certificate " << files[i] << '\n';
- certificate *cert = certificate_load(certdir + files[i]);
- if(false && !cert->validate()) {
- cerr << "Bad certificate!\n";
- continue;
- }
- certs[hexdecode(files[i])] = cert;
- }
-
- // TODO: save and load this value
- latest.tv_sec = 0;
- latest.tv_usec = 0;
-
- update_trust();
-}
-
-fides::~fides() {
- cerr << "Fides exitting\n";
- for(map<string, certificate *>::iterator i = certs.begin(); i != certs.end(); ++i)
- delete i->second;
- for(map<string, publickey *>::iterator i = keys.begin(); i != keys.end(); ++i)
- if(i->second != &mykey)
- delete i->second;
-}
-
-bool fides::fsck() {
- int errors = 0;
-
- for(map<string, certificate *>::iterator i = certs.begin(); i != certs.end(); ++i) {
- if(!i->second->validate()) {
- cerr << "Validation of certificate failed: " << i->second->to_string() << '\n';
- errors++;
- }
- }
-
- cerr << errors << " errors in " << certs.size() << " certificates\n";
- return !errors;
-}
-
-string fides::get_homedir() {
- return homedir;
-}
-
-bool fides::is_firstrun() {
- return firstrun;
-}
-
-fides::publickey *fides::find_key(const string &fingerprint) {
- map<string, publickey *>::iterator i;
- i = keys.find(fingerprint);
- if(i != keys.end())
- return i->second;
- else
- return 0;
-}
-
-vector<fides::certificate *> fides::find_certificates(publickey *signer, const string ®ex) {
- vector<certificate *> found;
- map<string, certificate *>::iterator i;
- regexp regexp(regex);
- for(i = certs.begin(); i != certs.end(); ++i) {
- if(!i->second) {
- cerr << "No certificate for " << hexencode(i->first) << '\n';
- continue;
- }
- if(i->second->signer == signer)
- if(regexp.match(i->second->statement))
- found.push_back(i->second);
- }
- return found;
-}
-
-vector<fides::certificate *> fides::find_certificates(const string ®ex) {
- vector<certificate *> found;
- map<string, certificate *>::iterator i;
- regexp regexp(regex);
- for(i = certs.begin(); i != certs.end(); ++i)
- if(regexp.match(i->second->statement))
- found.push_back(i->second);
- return found;
-}
-
-vector<fides::certificate *> fides::find_certificates(publickey *signer) {
- vector<certificate *> found;
- map<string, certificate *>::iterator i;
- for(i = certs.begin(); i != certs.end(); ++i)
- if(i->second->signer == signer)
- found.push_back(i->second);
- return found;
-}
-
-void fides::import_all(istream &in) {
- string line, pem;
- bool is_pem = false;
-
- while(getline(in, line)) {
- if(line.empty())
- continue;
-
- if(is_pem || !line.compare(0, 11, "-----BEGIN ")) {
- pem += line + '\n';
- if(!line.compare(0, 9, "-----END ")) {
- fides::publickey *key = new publickey();
- key->from_string(pem);
- cerr << "Imported key " << hexencode(key->fingerprint()) << '\n';
- merge(key);
- is_pem = false;
- } else {
- is_pem = true;
- }
- continue;
- }
-
- fides::certificate *cert = certificate_from_string(line);
- cerr << "Importing certificate " << hexencode(cert->fingerprint()) << '\n';
- merge(cert);
- }
-}
-
-void fides::export_all(ostream &out) {
- for(map<string, publickey *>::iterator i = keys.begin(); i != keys.end(); ++i)
- out << i->second->to_string();
- for(map<string, certificate *>::iterator i = certs.begin(); i != certs.end(); ++i)
- out << i->second->to_string() << '\n';
-}
-
-static int init() {
- fides fides;
- if(fides.is_firstrun()) {
- cout << "New keys generated in " << fides.get_homedir() << '\n';
- } else {
- cout << "Fides already initialised\n";
- }
- return 0;
-}
-
-void fides::trust(publickey *key) {
- string full = "t+ " + hexencode(key->fingerprint());
- sign(full);
-}
-
-void fides::distrust(publickey *key) {
- string full = "t- " + hexencode(key->fingerprint());
- sign(full);
-}
-
-void fides::dctrust(publickey *key) {
- string full = "t0 " + hexencode(key->fingerprint());
- sign(full);
-}
-
-static int is_trusted(int argc, char *const argv[]) {
- if(argc < 1)
- return EX_USAGE;
-
- fides fides;
- fides::publickey *key = fides.find_key(fides::hexdecode(argv[0]));
- if(!key) {
- cerr << "Unknown key!\n";
- return 1;
- }
- return fides.is_trusted(key) ? 0 : 1;
-}
-
-static int is_distrusted(int argc, char *const argv[]) {
- if(argc < 1)
- return EX_USAGE;
-
- fides fides;
- fides::publickey *key = fides.find_key(fides::hexdecode(argv[0]));
- if(!key) {
- cerr << "Unknown key!\n";
- return 1;
- }
- return fides.is_distrusted(key) ? 0 : 1;
-}
-
-static int trust(int argc, char *const argv[]) {
- if(argc < 1)
- return EX_USAGE;
-
- fides fides;
- fides::publickey *key = fides.find_key(fides::hexdecode(argv[0]));
- if(key)
- fides.trust(key);
- else {
- cerr << "Unknown key!\n";
- return -1;
- }
- return 0;
-}
-
-static int dctrust(int argc, char *const argv[]) {
- if(argc < 1)
- return EX_USAGE;
-
- fides fides;
- fides::publickey *key = fides.find_key(fides::hexdecode(argv[0]));
- if(key)
- fides.dctrust(key);
- else {
- cerr << "Unknown key!\n";
- return -1;
- }
- return 0;
-}
-
-static int distrust(int argc, char *const argv[]) {
- if(argc < 1)
- return EX_USAGE;
-
- fides fides;
- fides::publickey *key = fides.find_key(fides::hexdecode(argv[0]));
- if(key)
- fides.distrust(key);
- else {
- cerr << "Unknown key!\n";
- return -1;
- }
- return 0;
-}
-
-void fides::update_trust() {
- // clear trust on all keys
- for(map<string, publickey *>::iterator i = keys.begin(); i != keys.end(); ++i)
- i->second->trust = 0;
-
- // Start by checking all trust certificates from ourself.
- // If another key is positively or negatively trusted, update its trust score
- // and add it to the the list of new keys to check.
- // Then add our own key to the list of already checked keys.
- // Then check all the trust certificates of those on the tocheck list, etc.
- // Already checked keys are never updated anymore (TODO: is that smart?)
- // Certificates of keys with a zero or negative trust score are not processed.
-
- set<publickey *> checked;
- set<publickey *> tocheck;
- set<publickey *> newkeys;
- set<publickey *>::iterator i;
-
- mykey.trust = 3;
- tocheck.insert(&mykey);
-
- while(tocheck.size()) {
- // add
- checked.insert(tocheck.begin(), tocheck.end());
- newkeys.clear();
-
- // loop over all keys whose certificates need to be checked
-
- for(i = tocheck.begin(); i != tocheck.end(); ++i) {
- cerr << "Trust for key " << hexencode((*i)->fingerprint()) << " set to " << (*i)->trust << '\n';
-
- // except if this key is not trusted
-
- if((*i)->trust <= 0)
- continue;
-
- // find all non-zero trust certificates of this key
-
- vector<certificate *> matches = find_certificates(*i, "^t[+-] ");
-
- // update trust value of those keys
-
- for(size_t j = 0; j < matches.size(); j++) {
- publickey *other = find_key(hexdecode(matches[j]->statement.substr(3)));
-
- if(!other) {
- cerr << "Trust certificate for unknown key: " << matches[j]->to_string() << '\n';
- continue;
- }
-
- // except for keys we already checked
-
- if(checked.find(other) != checked.end()) {
- cerr << "Skipping trust certificate for already checked key: " << matches[j]->to_string() << '\n';
- continue;
- }
-
- // update trust
-
- if(matches[j]->statement[1] == '+')
- other->trust++;
- else
- other->trust--;
-
- newkeys.insert(other);
- }
- }
-
- tocheck = newkeys;
- }
-}
-
-void fides::merge(publickey *key) {
- if(keys.find(key->fingerprint()) != keys.end()) {
- cerr << "Key already known\n";
- return;
- }
-
- keys[key->fingerprint()] = key;
- key->save(keydir + hexencode(key->fingerprint()));
-}
-
-void fides::merge(certificate *cert) {
- // TODO: check if cert is already in database
- // TODO: check if cert obsoletes other certs
-
- // If we already know this certificate, drop it.
- if(certs.find(cert->fingerprint()) != certs.end()) {
- cerr << "Certificate already known\n";
- return;
- }
-
- // If the certificate does not validate, drop it.
- if(!cert->validate()) {
- // TODO: this should not happen, be wary of DoS attacks
- cerr << "Certificate invalid\n";
- return;
- }
-
- // TODO: move these regexps to the class?
- regexp authexp("^a[+0-] ");
- regexp trustexp("^t[+0-] ");
- vector<certificate *> others;
-
- // Is this an authorisation cert?
- if(authexp.match(cert->statement)) {
- // Find certs identical except for the +/-/0
- // TODO: escape statement in regexp
- others = find_certificates(cert->signer, string("^a[+0-] ") + cert->statement.substr(3) + '$');
- if(others.size()) {
- if(timercmp(&others[0]->timestamp, &cert->timestamp, >)) {
- cerr << "Certificate is overruled by a newer certificate\n";
- return;
- }
- if(timercmp(&others[0]->timestamp, &cert->timestamp, ==)) {
- // TODO: this should not happen, be wary of DoS attacks
- cerr << "Certificate has same timestamp as another timestamp!\n";
- return;
- }
- cerr << "Certificate overrules an older certificate!\n";
- // save new cert first
- certificate_save(cert, certdir + hexencode(cert->fingerprint()));
- certs[cert->fingerprint()] = cert;
-
- // delete old one
- rename((certdir + hexencode(others[0]->fingerprint())).c_str(), (obsoletedir + hexencode(others[0]->fingerprint())).c_str());
- certs.erase(others[0]->fingerprint());
- delete others[0];
- return;
- }
- }
-
- // Is this a trust cert?
- // TODO: it's just the same as above!
- if(trustexp.match(cert->statement)) {
- // Find certs identical except for the +/-/0
- // TODO: escape statement in regexp
- others = find_certificates(cert->signer, string("^t[+0-] ") + cert->statement.substr(3) + '$');
- if(others.size()) {
- if(timercmp(&others[0]->timestamp, &cert->timestamp, >)) {
- cerr << "Certificate is overruled by a newer certificate\n";
- return;
- }
- if(timercmp(&others[0]->timestamp, &cert->timestamp, ==)) {
- // TODO: this should not happen, be wary of DoS attacks
- cerr << "Certificate has same timestamp as another timestamp!\n";
- return;
- }
- cerr << "Certificate overrules an older certificate!\n";
- // delete old one
- rename((certdir + hexencode(others[0]->fingerprint())).c_str(), (obsoletedir + hexencode(others[0]->fingerprint())).c_str());
- certs.erase(others[0]->fingerprint());
- delete others[0];
- certs[cert->fingerprint()] = cert;
- certificate_save(cert, certdir + hexencode(cert->fingerprint()));
- return;
- }
- }
-
- // Did somebody sign the exact same statement twice?
- // Could happen if there is a different, conflicting statement between this new and the corresponding old one.
- others = find_certificates(cert->signer, string("^") + cert->statement + '$');
- if(others.size()) {
- if(timercmp(&others[0]->timestamp, &cert->timestamp, >)) {
- cerr << "Certificate is overruled by a newer certificate\n";
- return;
- }
- if(timercmp(&others[0]->timestamp, &cert->timestamp, ==)) {
- // TODO: this should not happen, be wary of DoS attacks
- cerr << "Certificate has same timestamp as another timestamp!\n";
- return;
- }
- cerr << "Certificate overrules an older certificate!\n";
- // delete old one
- rename((certdir + hexencode(others[0]->fingerprint())).c_str(), (obsoletedir + hexencode(others[0]->fingerprint())).c_str());
- certs.erase(others[0]->fingerprint());
- delete others[0];
- certs[cert->fingerprint()] = cert;
- certificate_save(cert, certdir + hexencode(cert->fingerprint()));
- return;
- }
-
- cerr << "Certificate is new\n";
- certs[cert->fingerprint()] = cert;
- certificate_save(cert, certdir + hexencode(cert->fingerprint()));
-}
-
-void fides::auth_stats(const string &statement, int &self, int &trusted, int &all) {
- self = trusted = all = 0;
- vector<certificate *> matches = find_certificates(string("^a[+0-] ") + statement + '$');
- for(size_t i = 0; i < matches.size(); ++i) {
- char code = matches[i]->statement[1];
- int diff = 0;
- if(code == '+')
- diff = 1;
- else if(code == '-')
- diff = -1;
- if(matches[i]->signer == &mykey)
- self += diff;
- if(matches[i]->signer->trust > 0)
- trusted += diff;
- all += diff;
- }
-}
-
-bool fides::is_trusted(publickey *key) {
- return key->trust > 0;
-}
-
-bool fides::is_distrusted(publickey *key) {
- return key->trust < 0;
-}
-
-bool fides::is_allowed(const string &statement, publickey *key) {
- int self, trusted, all;
-
- if(key)
- auth_stats(hexencode(key->fingerprint()) + " " + statement, self, trusted, all);
- else
- auth_stats(statement, self, trusted, all);
-
- if(self)
- return self > 0;
- else if(trusted)
- return trusted > 0;
- else
- return false;
-}
-
-bool fides::is_denied(const string &statement, publickey *key) {
- int self, trusted, all;
-
- if(key)
- auth_stats(hexencode(key->fingerprint()) + " " + statement, self, trusted, all);
- else
- auth_stats(statement, self, trusted, all);
-
- if(self)
- return self < 0;
- else if(trusted)
- return trusted < 0;
- else
- return false;
-}
-
-void fides::sign(const string &statement) {
- // Try to set "latest" to now, but ensure monoticity
- struct timeval now;
- gettimeofday(&now, 0);
- if(timercmp(&latest, &now, >=)) {
- latest.tv_usec++;
- if(latest.tv_usec >= 1000000) {
- latest.tv_sec++;
- latest.tv_usec -= 1000000;
- }
- } else {
- latest = now;
- }
-
- // Create a new certificate and merge it with our database
- merge(new certificate(&mykey, latest, statement));
-}
-
-void fides::allow(const string &statement, publickey *key) {
- string full = "a+ ";
- if(key)
- full += hexencode(key->fingerprint()) + ' ';
- full += statement;
- sign(full);
-}
-
-void fides::dontcare(const string &statement, publickey *key) {
- string full = "a0 ";
- if(key)
- full += hexencode(key->fingerprint()) + ' ';
- full += statement;
- sign(full);
-}
-
-void fides::deny(const string &statement, publickey *key) {
- string full = "a- ";
- if(key)
- full += hexencode(key->fingerprint()) + ' ';
- full += statement;
- sign(full);
-}
-
-static int sign(int argc, char *const argv[]) {
- if(argc < 1)
- return EX_USAGE;
-
- fides fides;
- fides.sign(argv[0]);
- return 0;
-}
-
-static int allow(int argc, char *const argv[]) {
- if(argc < 1)
- return EX_USAGE;
-
- fides fides;
- fides.allow(argv[0]);
- return 0;
-}
-
-static int dontcare(int argc, char *const argv[]) {
- if(argc < 1)
- return EX_USAGE;
-
- fides fides;
- fides.dontcare(argv[0]);
- return 0;
-}
-
-static int deny(int argc, char *const argv[]) {
- if(argc < 1)
- return EX_USAGE;
-
- fides fides;
- fides.deny(argv[0]);
- return 0;
-}
-
-static int import(int argc, char *const argv[]) {
- fides fides;
-
- if(argc) {
- ifstream in(argv[0]);
- fides.import_all(in);
- } else
- fides.import_all(cin);
- return 0;
-}
-
-static int exprt(int argc, char *const argv[]) {
- fides fides;
-
- if(argc) {
- ofstream out(argv[0]);
- fides.export_all(out);
- } else
- fides.export_all(cout);
- return 0;
-}
-
-static int find(int argc, char *const argv[]) {
- if(argc < 1)
- return EX_USAGE;
-
- // Find certificates matching statement
- fides fides;
- const vector<fides::certificate *> &certs = fides.find_certificates(argv[0]);
- for(size_t i = 0; i < certs.size(); ++i)
- cout << i << ' ' << certs[i]->to_string() << '\n';
- return 0;
-}
-
-static int is_allowed(int argc, char *const argv[]) {
- if(argc < 1)
- return EX_USAGE;
-
- fides fides;
- return fides.is_allowed(argv[0]) ? 0 : 1;
-}
-
-static int is_denied(int argc, char *const argv[]) {
- if(argc < 1)
- return EX_USAGE;
-
- fides fides;
- return fides.is_denied(argv[0]) ? 0 : 1;
-}
-
-static int test(int argc, char *const argv[]) {
- if(argc < 1)
- return EX_USAGE;
-
- fides fides;
- int self, trusted, all;
- fides.auth_stats(argv[0], self, trusted, all);
- cout << "Self: " << self << ", trusted: " << trusted << ", all: " << all << '\n';
- return 0;
-}
-
-static int fsck() {
- fides fides;
- if(fides.fsck()) {
- cout << "Everything OK\n";
- return 0;
- } else {
- cout << "Integrity failure!\n";
- return 1;
- }
-}
-
-int main(int argc, char *const argv[]) {
- int r;
- int option_index;
-
- static struct option const long_options[] = {
- {"homedir", required_argument, NULL, 2},
- {"help", no_argument, NULL, 'h'},
- {"version", no_argument, NULL, 3},
- {NULL, 0, NULL, 0}
- };
-
- while((r = getopt_long(argc, argv, "h", long_options, &option_index)) != EOF) {
- switch (r) {
- case 0: /* long option */
- break;
- case 1: /* non-option */
- break;
- case 2:
- //homedir = strdup(optarg);
- break;
- case 3:
- version();
- return 0;
- case 'h':
- help(cout, argv[0]);
- return 0;
- }
- }
-
- if(argc < 2) {
- help(cerr, argv[0]);
- return EX_USAGE;
- }
-
- if(!strcmp(argv[1], "help")) {
- help(cout, argv[0]);
- return 0;
- }
-
- if(!strcmp(argv[1], "version")) {
- version();
- return 0;
- }
-
- if(!strcmp(argv[1], "init"))
- return init();
-
- if(!strcmp(argv[1], "trust"))
- return trust(argc - 2, argv + 2);
-
- if(!strcmp(argv[1], "dctrust"))
- return dctrust(argc - 2, argv + 2);
-
- if(!strcmp(argv[1], "distrust"))
- return distrust(argc - 2, argv + 2);
-
- if(!strcmp(argv[1], "is_trusted"))
- return is_trusted(argc - 2, argv + 2);
-
- if(!strcmp(argv[1], "is_distrusted"))
- return is_distrusted(argc - 2, argv + 2);
-
- if(!strcmp(argv[1], "is_allowed"))
- return is_allowed(argc - 2, argv + 2);
-
- if(!strcmp(argv[1], "is_denied"))
- return is_denied(argc - 2, argv + 2);
-
- if(!strcmp(argv[1], "allow"))
- return allow(argc - 2, argv + 2);
-
- if(!strcmp(argv[1], "dontcare"))
- return dontcare(argc - 2, argv + 2);
-
- if(!strcmp(argv[1], "deny"))
- return deny(argc - 2, argv + 2);
-
- if(!strcmp(argv[1], "sign"))
- return sign(argc - 2, argv + 2);
-
- if(!strcmp(argv[1], "import"))
- return import(argc - 2, argv + 2);
-
- if(!strcmp(argv[1], "export"))
- return exprt(argc - 2, argv + 2);
-
- if(!strcmp(argv[1], "test"))
- return test(argc - 2, argv + 2);
-
- if(!strcmp(argv[1], "find"))
- return find(argc - 2, argv + 2);
-
- if(!strcmp(argv[1], "fsck"))
- return fsck();
-
- cerr << "Unknown command: " << argv[1] << '\n';
- return EX_USAGE;
-}
-