/**
* Authenticate in the SSH server with key
* @param QString private_key the private key to use for connect in the SSH server
* @param QString password the password to use for connect in the SSH server (passphrase of the private key)
* @return bool true if it's ok, false else
* @todo test with a private key with passphrase
*/
bool Kssh::authenticateKey(QString private_key, QString password)
{
ssh_string public_key_to_use;
ssh_private_key private_key_to_use;
int auth;
private_key_to_use = privatekey_from_file(this->m_session, private_key.toStdString().c_str(), 0, password.toStdString().c_str());
if (private_key_to_use == NULL) {
Klog::error(QString("Fatal error while get the private key : ") + QString(ssh_get_error(this->m_session)));
return false;
}
// get the public key
public_key_to_use = publickey_to_string(publickey_from_privatekey(private_key_to_use));
// try to authenticate
auth = ssh_userauth_pubkey(this->m_session, NULL, public_key_to_use, private_key_to_use);
if (auth == SSH_AUTH_SUCCESS) {
// clear the keys of the memory
privatekey_free(private_key_to_use);
string_free(public_key_to_use);
// it's ok
return true;
} else if (auth == SSH_AUTH_DENIED || auth == SSH_AUTH_PARTIAL) {
Klog::warning(QString("Authenticated denied with this key"));
return false;
} else if (auth == SSH_AUTH_ERROR) {
Klog::error(QString("Fatal error in authenticated with key : ") + QString(ssh_get_error(this->m_session)));
return false;
}
return false;
}
static void torture_pubkey_generate_from_privkey(void **state) {
ssh_session session = *state;
ssh_private_key privkey = NULL;
ssh_public_key pubkey = NULL;
ssh_string pubkey_orig = NULL;
ssh_string pubkey_new = NULL;
char pubkey_line_orig[512] = {0};
char pubkey_line_new[512] = {0};
int type_orig = 0;
int type_new = 0;
int rc;
/* read the publickey */
rc = ssh_try_publickey_from_file(session, LIBSSH_RSA_TESTKEY, &pubkey_orig,
&type_orig);
assert_true(rc == 0);
assert_true(pubkey_orig != NULL);
rc = torture_read_one_line(LIBSSH_RSA_TESTKEY ".pub", pubkey_line_orig,
sizeof(pubkey_line_orig));
assert_true(rc == 0);
/* remove the public key, generate it from the private key and write it. */
unlink(LIBSSH_RSA_TESTKEY ".pub");
privkey = privatekey_from_file(session, LIBSSH_RSA_TESTKEY, 0, NULL);
assert_true(privkey != NULL);
pubkey = publickey_from_privatekey(privkey);
assert_true(pubkey != NULL);
type_new = privkey->type;
privatekey_free(privkey);
pubkey_new = publickey_to_string(pubkey);
publickey_free(pubkey);
assert_true(pubkey_new != NULL);
assert_true(ssh_string_len(pubkey_orig) == ssh_string_len(pubkey_new));
assert_memory_equal(ssh_string_data(pubkey_orig),
ssh_string_data(pubkey_new),
ssh_string_len(pubkey_orig));
rc = ssh_publickey_to_file(session, LIBSSH_RSA_TESTKEY ".pub", pubkey_new, type_new);
assert_true(rc == 0);
rc = torture_read_one_line(LIBSSH_RSA_TESTKEY ".pub", pubkey_line_new,
sizeof(pubkey_line_new));
assert_true(rc == 0);
assert_string_equal(pubkey_line_orig, pubkey_line_new);
ssh_string_free(pubkey_orig);
ssh_string_free(pubkey_new);
}
gboolean remmina_nx_session_open(RemminaNXSession *nx, const gchar *server, guint port, const gchar *private_key_file,
RemminaNXPassphraseCallback passphrase_func, gpointer userdata)
{
gint ret;
ssh_private_key privkey;
ssh_public_key pubkey;
ssh_string pubkeystr;
gint keytype;
gboolean encrypted;
gchar *passphrase = NULL;
gchar tmpfile[L_tmpnam + 1];
nx ->session = ssh_new();
ssh_options_set(nx->session, SSH_OPTIONS_HOST, server);
ssh_options_set(nx->session, SSH_OPTIONS_PORT, &port);
ssh_options_set(nx->session, SSH_OPTIONS_USER, "nx");
if (private_key_file && private_key_file[0])
{
if (!remmina_get_keytype(private_key_file, &keytype, &encrypted))
{
remmina_nx_session_set_application_error(nx, "Invalid private key file.");
return FALSE;
}
if (encrypted && !passphrase_func(&passphrase, userdata))
{
return FALSE;
}
privkey = privatekey_from_file(nx->session, private_key_file, keytype, (passphrase ? passphrase : ""));
g_free(passphrase);
}
else
{
/* Use NoMachine's default nx private key */
if ((tmpnam(tmpfile)) == NULL || !g_file_set_contents(tmpfile, nx_default_private_key, -1, NULL))
{
remmina_nx_session_set_application_error(nx, "Failed to create temporary private key file.");
return FALSE;
}
privkey = privatekey_from_file(nx->session, tmpfile, REMMINA_SSH_TYPE_DSS, "");
g_unlink(tmpfile);
}
if (privkey == NULL)
{
remmina_nx_session_set_error(nx, "Invalid private key file: %s");
return FALSE;
}
pubkey = publickey_from_privatekey(privkey);
pubkeystr = publickey_to_string(pubkey);
publickey_free(pubkey);
if (ssh_connect(nx->session))
{
string_free(pubkeystr);
privatekey_free(privkey);
remmina_nx_session_set_error(nx, "Failed to startup SSH session: %s");
return FALSE;
}
ret = ssh_userauth_pubkey(nx->session, NULL, pubkeystr, privkey);
string_free(pubkeystr);
privatekey_free(privkey);
if (ret != SSH_AUTH_SUCCESS)
{
remmina_nx_session_set_error(nx, "NX SSH authentication failed: %s");
return FALSE;
}
if ((nx->channel = channel_new(nx->session)) == NULL || channel_open_session(nx->channel))
{
return FALSE;
}
if (channel_request_shell(nx->channel))
{
return FALSE;
}
/* NX server starts the session with an initial 105 status */
if (!remmina_nx_session_expect_status(nx, 105))
return FALSE;
/* Say hello to the NX server */
remmina_nx_session_send_command(nx, "HELLO NXCLIENT - Version %s", nx->version);
if (!remmina_nx_session_expect_status(nx, 105))
return FALSE;
/* Set the NX session environment */
remmina_nx_session_send_command(nx, "SET SHELL_MODE SHELL");
if (!remmina_nx_session_expect_status(nx, 105))
return FALSE;
remmina_nx_session_send_command(nx, "SET AUTH_MODE PASSWORD");
if (!remmina_nx_session_expect_status(nx, 105))
return FALSE;
nx->server = g_strdup(server);
return TRUE;
}
static int dh_handshake_server(ssh_session session) {
ssh_string f;
ssh_string pubkey;
ssh_string sign;
ssh_public_key pub;
ssh_private_key prv;
if (dh_generate_y(session) < 0) {
ssh_set_error(session, SSH_FATAL, "Could not create y number");
return -1;
}
if (dh_generate_f(session) < 0) {
ssh_set_error(session, SSH_FATAL, "Could not create f number");
return -1;
}
f = dh_get_f(session);
if (f == NULL) {
ssh_set_error(session, SSH_FATAL, "Could not get the f number");
return -1;
}
switch(session->hostkeys){
case SSH_KEYTYPE_DSS:
prv = session->dsa_key;
break;
case SSH_KEYTYPE_RSA:
prv = session->rsa_key;
break;
default:
prv = NULL;
}
pub = publickey_from_privatekey(prv);
if (pub == NULL) {
ssh_set_error(session, SSH_FATAL,
"Could not get the public key from the private key");
ssh_string_free(f);
return -1;
}
pubkey = publickey_to_string(pub);
publickey_free(pub);
if (pubkey == NULL) {
ssh_set_error(session, SSH_FATAL, "Not enough space");
ssh_string_free(f);
return -1;
}
dh_import_pubkey(session, pubkey);
if (dh_build_k(session) < 0) {
ssh_set_error(session, SSH_FATAL, "Could not import the public key");
ssh_string_free(f);
return -1;
}
if (make_sessionid(session) != SSH_OK) {
ssh_set_error(session, SSH_FATAL, "Could not create a session id");
ssh_string_free(f);
return -1;
}
sign = ssh_sign_session_id(session, prv);
if (sign == NULL) {
ssh_set_error(session, SSH_FATAL, "Could not sign the session id");
ssh_string_free(f);
return -1;
}
/* Free private keys as they should not be readable after this point */
if (session->rsa_key) {
privatekey_free(session->rsa_key);
session->rsa_key = NULL;
}
if (session->dsa_key) {
privatekey_free(session->dsa_key);
session->dsa_key = NULL;
}
if (buffer_add_u8(session->out_buffer, SSH2_MSG_KEXDH_REPLY) < 0 ||
buffer_add_ssh_string(session->out_buffer, pubkey) < 0 ||
buffer_add_ssh_string(session->out_buffer, f) < 0 ||
buffer_add_ssh_string(session->out_buffer, sign) < 0) {
ssh_set_error(session, SSH_FATAL, "Not enough space");
buffer_reinit(session->out_buffer);
ssh_string_free(f);
ssh_string_free(sign);
return -1;
}
ssh_string_free(f);
ssh_string_free(sign);
if (packet_send(session) == SSH_ERROR) {
return -1;
}
if (buffer_add_u8(session->out_buffer, SSH2_MSG_NEWKEYS) < 0) {
buffer_reinit(session->out_buffer);
return -1;
}
if (packet_send(session) == SSH_ERROR) {
return -1;
}
ssh_log(session, SSH_LOG_PACKET, "SSH_MSG_NEWKEYS sent");
session->dh_handshake_state=DH_STATE_NEWKEYS_SENT;
return 0;
}
static int dh_handshake_server(SSH_SESSION *session) {
STRING *e;
STRING *f;
STRING *pubkey;
STRING *sign;
PUBLIC_KEY *pub;
PRIVATE_KEY *prv;
if (packet_wait(session, SSH2_MSG_KEXDH_INIT, 1) != SSH_OK) {
return -1;
}
e = buffer_get_ssh_string(session->in_buffer);
if (e == NULL) {
ssh_set_error(session, SSH_FATAL, "No e number in client request");
return -1;
}
if (dh_import_e(session, e) < 0) {
ssh_set_error(session, SSH_FATAL, "Cannot import e number");
string_free(e);
return -1;
}
string_free(e);
if (dh_generate_y(session) < 0) {
ssh_set_error(session, SSH_FATAL, "Could not create y number");
return -1;
}
if (dh_generate_f(session) < 0) {
ssh_set_error(session, SSH_FATAL, "Could not create f number");
return -1;
}
f = dh_get_f(session);
if (f == NULL) {
ssh_set_error(session, SSH_FATAL, "Could not get the f number");
return -1;
}
switch(session->hostkeys){
case TYPE_DSS:
prv = session->dsa_key;
break;
case TYPE_RSA:
prv = session->rsa_key;
break;
default:
prv = NULL;
}
pub = publickey_from_privatekey(prv);
if (pub == NULL) {
ssh_set_error(session, SSH_FATAL,
"Could not get the public key from the private key");
string_free(f);
return -1;
}
pubkey = publickey_to_string(pub);
publickey_free(pub);
if (pubkey == NULL) {
ssh_set_error(session, SSH_FATAL, "Not enough space");
string_free(f);
return -1;
}
dh_import_pubkey(session, pubkey);
if (dh_build_k(session) < 0) {
ssh_set_error(session, SSH_FATAL, "Could not import the public key");
string_free(f);
return -1;
}
if (make_sessionid(session) != SSH_OK) {
ssh_set_error(session, SSH_FATAL, "Could not create a session id");
string_free(f);
return -1;
}
sign = ssh_sign_session_id(session, prv);
if (sign == NULL) {
ssh_set_error(session, SSH_FATAL, "Could not sign the session id");
string_free(f);
return -1;
}
/* Free private keys as they should not be readable after this point */
if (session->rsa_key) {
privatekey_free(session->rsa_key);
session->rsa_key = NULL;
}
if (session->dsa_key) {
privatekey_free(session->dsa_key);
session->dsa_key = NULL;
}
if (buffer_add_u8(session->out_buffer, SSH2_MSG_KEXDH_REPLY) < 0 ||
buffer_add_ssh_string(session->out_buffer, pubkey) < 0 ||
buffer_add_ssh_string(session->out_buffer, f) < 0 ||
buffer_add_ssh_string(session->out_buffer, sign) < 0) {
ssh_set_error(session, SSH_FATAL, "Not enough space");
buffer_free(session->out_buffer);
string_free(f);
string_free(sign);
return -1;
}
string_free(f);
string_free(sign);
if (packet_send(session) != SSH_OK) {
return -1;
}
if (buffer_add_u8(session->out_buffer, SSH2_MSG_NEWKEYS) < 0) {
buffer_free(session->out_buffer);
return -1;
}
if (packet_send(session) != SSH_OK) {
return -1;
}
ssh_log(session, SSH_LOG_PACKET, "SSH_MSG_NEWKEYS sent");
if (packet_wait(session, SSH2_MSG_NEWKEYS, 1) != SSH_OK) {
return -1;
}
ssh_log(session, SSH_LOG_PACKET, "Got SSH_MSG_NEWKEYS");
if (generate_session_keys(session) < 0) {
return -1;
}
/*
* Once we got SSH2_MSG_NEWKEYS we can switch next_crypto and
* current_crypto
*/
if (session->current_crypto) {
crypto_free(session->current_crypto);
}
/* FIXME TODO later, include a function to change keys */
session->current_crypto = session->next_crypto;
session->next_crypto = crypto_new();
if (session->next_crypto == NULL) {
return -1;
}
return 0;
}
/**
* @brief Tries to automaticaly authenticate with public key and "none"
*
* It may fail, for instance it doesn't ask for a password and uses a default
* asker for passphrases (in case the private key is encrypted).
*
* @param session The ssh session to authenticate with.
*
* @param passphrase Use this passphrase to unlock the privatekey. Use NULL
* if you don't want to use a passphrase or the user
* should be asked.
*
* @returns SSH_AUTH_ERROR: A serious error happened\n
* SSH_AUTH_DENIED: Authentication failed: use another method\n
* SSH_AUTH_PARTIAL: You've been partially authenticated, you still
* have to use another method\n
* SSH_AUTH_SUCCESS: Authentication success
*
* @see ssh_userauth_kbdint()
* @see ssh_userauth_password()
*/
int ssh_userauth_autopubkey(ssh_session session, const char *passphrase) {
struct ssh_iterator *it;
ssh_private_key privkey;
ssh_public_key pubkey;
ssh_string pubkey_string;
int type = 0;
int rc;
enter_function();
/* Always test none authentication */
rc = ssh_userauth_none(session, NULL);
if (rc == SSH_AUTH_ERROR || rc == SSH_AUTH_SUCCESS) {
leave_function();
return rc;
}
/* Try authentication with ssh-agent first */
#ifndef _WIN32
if (agent_is_running(session)) {
char *privkey_file = NULL;
ssh_log(session, SSH_LOG_RARE,
"Trying to authenticate with SSH agent keys as user: %s",
session->username);
for (pubkey = agent_get_first_ident(session, &privkey_file);
pubkey != NULL;
pubkey = agent_get_next_ident(session, &privkey_file)) {
ssh_log(session, SSH_LOG_RARE, "Trying identity %s", privkey_file);
pubkey_string = publickey_to_string(pubkey);
if (pubkey_string) {
rc = ssh_userauth_offer_pubkey(session, NULL, pubkey->type, pubkey_string);
string_free(pubkey_string);
if (rc == SSH_AUTH_ERROR) {
SAFE_FREE(privkey_file);
publickey_free(pubkey);
leave_function();
return rc;
} else if (rc != SSH_AUTH_SUCCESS) {
ssh_log(session, SSH_LOG_PROTOCOL, "Public key refused by server");
SAFE_FREE(privkey_file);
publickey_free(pubkey);
continue;
}
ssh_log(session, SSH_LOG_RARE, "Public key accepted");
/* pubkey accepted by server ! */
rc = ssh_userauth_agent_pubkey(session, NULL, pubkey);
if (rc == SSH_AUTH_ERROR) {
SAFE_FREE(privkey_file);
publickey_free(pubkey);
leave_function();
return rc;
} else if (rc != SSH_AUTH_SUCCESS) {
ssh_log(session, SSH_LOG_RARE,
"Server accepted public key but refused the signature ;"
" It might be a bug of libssh");
SAFE_FREE(privkey_file);
publickey_free(pubkey);
continue;
}
/* auth success */
ssh_log(session, SSH_LOG_PROTOCOL, "Authentication using %s success",
privkey_file);
SAFE_FREE(privkey_file);
publickey_free(pubkey);
leave_function();
return SSH_AUTH_SUCCESS;
} /* if pubkey */
SAFE_FREE(privkey_file);
publickey_free(pubkey);
} /* for each privkey */
} /* if agent is running */
#endif
for (it = ssh_list_get_iterator(session->identity);
it != NULL;
it = it->next) {
const char *privkey_file = it->data;
int privkey_open = 0;
privkey = NULL;
ssh_log(session, SSH_LOG_PROTOCOL, "Trying to read privatekey %s", privkey_file);
rc = ssh_try_publickey_from_file(session, privkey_file, &pubkey_string, &type);
if (rc == 1) {
char *publickey_file;
size_t len;
privkey = privatekey_from_file(session, privkey_file, type, passphrase);
if (privkey == NULL) {
ssh_log(session, SSH_LOG_RARE,
"Reading private key %s failed (bad passphrase ?)",
privkey_file);
leave_function();
return SSH_AUTH_ERROR;
}
privkey_open = 1;
pubkey = publickey_from_privatekey(privkey);
if (pubkey == NULL) {
privatekey_free(privkey);
ssh_set_error_oom(session);
leave_function();
return SSH_AUTH_ERROR;
}
pubkey_string = publickey_to_string(pubkey);
type = pubkey->type;
publickey_free(pubkey);
if (pubkey_string == NULL) {
ssh_set_error_oom(session);
leave_function();
return SSH_AUTH_ERROR;
}
len = strlen(privkey_file) + 5;
publickey_file = malloc(len);
if (publickey_file == NULL) {
ssh_set_error_oom(session);
leave_function();
return SSH_AUTH_ERROR;
}
snprintf(publickey_file, len, "%s.pub", privkey_file);
rc = ssh_publickey_to_file(session, publickey_file, pubkey_string, type);
if (rc < 0) {
ssh_log(session, SSH_LOG_PACKET,
"Could not write public key to file: %s", publickey_file);
}
SAFE_FREE(publickey_file);
} else if (rc < 0) {
continue;
}
rc = ssh_userauth_offer_pubkey(session, NULL, type, pubkey_string);
if (rc == SSH_AUTH_ERROR){
string_free(pubkey_string);
ssh_log(session, SSH_LOG_RARE, "Publickey authentication error");
leave_function();
return rc;
} else {
if (rc != SSH_AUTH_SUCCESS){
ssh_log(session, SSH_LOG_PROTOCOL, "Publickey refused by server");
string_free(pubkey_string);
continue;
}
}
/* Public key accepted by server! */
if (!privkey_open) {
ssh_log(session, SSH_LOG_PROTOCOL, "Trying to read privatekey %s",
privkey_file);
privkey = privatekey_from_file(session, privkey_file, type, passphrase);
if (privkey == NULL) {
ssh_log(session, SSH_LOG_RARE,
"Reading private key %s failed (bad passphrase ?)",
privkey_file);
string_free(pubkey_string);
continue; /* continue the loop with other pubkey */
}
}
rc = ssh_userauth_pubkey(session, NULL, pubkey_string, privkey);
if (rc == SSH_AUTH_ERROR) {
string_free(pubkey_string);
privatekey_free(privkey);
leave_function();
return rc;
} else {
if (rc != SSH_AUTH_SUCCESS){
ssh_log(session, SSH_LOG_FUNCTIONS,
"The server accepted the public key but refused the signature");
string_free(pubkey_string);
privatekey_free(privkey);
continue;
}
}
/* auth success */
ssh_log(session, SSH_LOG_PROTOCOL,
"Successfully authenticated using %s", privkey_file);
string_free(pubkey_string);
privatekey_free(privkey);
leave_function();
return SSH_AUTH_SUCCESS;
}
/* at this point, pubkey is NULL and so is privkeyfile */
ssh_log(session, SSH_LOG_FUNCTIONS,
"Tried every public key, none matched");
ssh_set_error(session,SSH_NO_ERROR,"No public key matched");
leave_function();
return SSH_AUTH_DENIED;
}
static int dh_handshake_server(SSH_SESSION *session){
STRING *e,*f,*pubkey,*sign;
PUBLIC_KEY *pub;
PRIVATE_KEY *prv;
BUFFER *buf=buffer_new();
if(packet_wait(session, SSH2_MSG_KEXDH_INIT)) // FIXME BLOCKING
return -1;
e=buffer_get_ssh_string(session->in_buffer);
if(!e){
ssh_set_error(session,SSH_FATAL,"No e number in client request");
return -1;
}
dh_import_e(session,e);
dh_generate_y(session);
dh_generate_f(session);
f=dh_get_f(session);
switch(session->hostkeys){
case TYPE_DSS:
prv=session->dsa_key;
break;
case TYPE_RSA:
prv=session->rsa_key;
break;
default:
prv=NULL;
}
pub=publickey_from_privatekey(prv);
pubkey=publickey_to_string(pub);
publickey_free(pub);
dh_import_pubkey(session,pubkey);
dh_build_k(session);
make_sessionid(session);
sign=ssh_sign_session_id(session,prv);
buffer_free(buf);
/* free private keys as they should not be readable past this point */
if(session->rsa_key){
private_key_free(session->rsa_key);
session->rsa_key=NULL;
}
if(session->dsa_key){
private_key_free(session->dsa_key);
session->dsa_key=NULL;
}
buffer_add_u8(session->out_buffer,SSH2_MSG_KEXDH_REPLY);
buffer_add_ssh_string(session->out_buffer,pubkey);
buffer_add_ssh_string(session->out_buffer,f);
buffer_add_ssh_string(session->out_buffer,sign);
free(sign);
packet_send(session);
free(f);
packet_clear_out(session);
buffer_add_u8(session->out_buffer,SSH2_MSG_NEWKEYS);
packet_send(session);
ssh_say(2,"SSH_MSG_NEWKEYS sent\n");
packet_wait(session,SSH2_MSG_NEWKEYS);// FIXME BLOCKING
ssh_say(2,"Got SSH_MSG_NEWKEYS\n");
generate_session_keys(session);
/* once we got SSH2_MSG_NEWKEYS we can switch next_crypto and current_crypto */
if(session->current_crypto)
crypto_free(session->current_crypto);
/* XXX later, include a function to change keys */
session->current_crypto=session->next_crypto;
session->next_crypto=crypto_new();
return 0;
}