/* sends challenge back to the server */
static int kbdauth_send(ssh_session session) {
ssh_string answer = NULL;
int rc = SSH_AUTH_ERROR;
uint32_t i;
enter_function();
if (buffer_add_u8(session->out_buffer, SSH2_MSG_USERAUTH_INFO_RESPONSE) < 0 ||
buffer_add_u32(session->out_buffer,
htonl(session->kbdint->nprompts)) < 0) {
goto error;
}
for (i = 0; i < session->kbdint->nprompts; i++) {
if (session->kbdint->answers[i]) {
answer = string_from_char(session->kbdint->answers[i]);
} else {
answer = string_from_char("");
}
if (answer == NULL) {
goto error;
}
if (buffer_add_ssh_string(session->out_buffer, answer) < 0) {
goto error;
}
string_burn(answer);
string_free(answer);
}
if (packet_send(session) != SSH_OK) {
leave_function();
return rc;
}
rc = wait_auth_status(session,1);
leave_function();
return rc;
error:
buffer_reinit(session->out_buffer);
string_burn(answer);
string_free(answer);
leave_function();
return rc;
}
/* sends challenge back to the server */
static int kbdauth_send(SSH_SESSION *session) {
STRING *answer;
u32 i;
int err;
enter_function();
buffer_add_u8(session->out_buffer,SSH2_MSG_USERAUTH_INFO_RESPONSE);
buffer_add_u32(session->out_buffer,htonl(session->kbdint->nprompts));
for(i=0;i<session->kbdint->nprompts;++i){
if(session->kbdint->answers[i])
answer=string_from_char(session->kbdint->answers[i]);
else
answer=string_from_char("");
buffer_add_ssh_string(session->out_buffer,answer);
string_burn(answer);
free(answer);
}
if(packet_send(session)){
leave_function();
return SSH_AUTH_ERROR;
}
err = wait_auth_status(session,1);
leave_function();
return err;
}
ssh_public_key publickey_make_dss(ssh_session session, ssh_buffer buffer) {
ssh_string p = NULL;
ssh_string q = NULL;
ssh_string g = NULL;
ssh_string pubkey = NULL;
ssh_public_key key = NULL;
key = malloc(sizeof(struct ssh_public_key_struct));
if (key == NULL) {
buffer_free(buffer);
return NULL;
}
key->type = TYPE_DSS;
key->type_c = ssh_type_to_char(key->type);
p = buffer_get_ssh_string(buffer);
q = buffer_get_ssh_string(buffer);
g = buffer_get_ssh_string(buffer);
pubkey = buffer_get_ssh_string(buffer);
buffer_free(buffer); /* we don't need it anymore */
if (p == NULL || q == NULL || g == NULL || pubkey == NULL) {
ssh_set_error(session, SSH_FATAL, "Invalid DSA public key");
goto error;
}
#ifdef HAVE_LIBGCRYPT
gcry_sexp_build(&key->dsa_pub, NULL,
"(public-key(dsa(p %b)(q %b)(g %b)(y %b)))",
string_len(p), string_data(p),
string_len(q), string_data(q),
string_len(g), string_data(g),
string_len(pubkey), string_data(pubkey));
if (key->dsa_pub == NULL) {
goto error;
}
#elif defined HAVE_LIBCRYPTO
key->dsa_pub = DSA_new();
if (key->dsa_pub == NULL) {
goto error;
}
key->dsa_pub->p = make_string_bn(p);
key->dsa_pub->q = make_string_bn(q);
key->dsa_pub->g = make_string_bn(g);
key->dsa_pub->pub_key = make_string_bn(pubkey);
if (key->dsa_pub->p == NULL ||
key->dsa_pub->q == NULL ||
key->dsa_pub->g == NULL ||
key->dsa_pub->pub_key == NULL) {
goto error;
}
#endif /* HAVE_LIBCRYPTO */
#ifdef DEBUG_CRYPTO
ssh_print_hexa("p", string_data(p), string_len(p));
ssh_print_hexa("q", string_data(q), string_len(q));
ssh_print_hexa("g", string_data(g), string_len(g));
#endif
string_burn(p);
string_free(p);
string_burn(q);
string_free(q);
string_burn(g);
string_free(g);
string_burn(pubkey);
string_free(pubkey);
return key;
error:
string_burn(p);
string_free(p);
string_burn(q);
string_free(q);
string_burn(g);
string_free(g);
string_burn(pubkey);
string_free(pubkey);
publickey_free(key);
return NULL;
}
static int rsa_public_to_string(gcry_sexp_t key, ssh_buffer buffer) {
#elif defined HAVE_LIBCRYPTO
static int rsa_public_to_string(RSA *key, ssh_buffer buffer) {
#endif
ssh_string e = NULL;
ssh_string n = NULL;
int rc = -1;
#ifdef HAVE_LIBGCRYPT
const char *tmp;
size_t size;
gcry_sexp_t sexp;
sexp = gcry_sexp_find_token(key, "n", 0);
if (sexp == NULL) {
goto error;
}
tmp = gcry_sexp_nth_data(sexp, 1, &size);
n = string_new(size);
if (n == NULL) {
goto error;
}
string_fill(n, (char *) tmp, size);
gcry_sexp_release(sexp);
sexp = gcry_sexp_find_token(key, "e", 0);
if (sexp == NULL) {
goto error;
}
tmp = gcry_sexp_nth_data(sexp, 1, &size);
e = string_new(size);
if (e == NULL) {
goto error;
}
string_fill(e, (char *) tmp, size);
#elif defined HAVE_LIBCRYPTO
e = make_bignum_string(key->e);
n = make_bignum_string(key->n);
if (e == NULL || n == NULL) {
goto error;
}
#endif
if (buffer_add_ssh_string(buffer, e) < 0) {
goto error;
}
if (buffer_add_ssh_string(buffer, n) < 0) {
goto error;
}
rc = 0;
error:
#ifdef HAVE_LIBGCRYPT
gcry_sexp_release(sexp);
#endif
string_burn(e);
string_free(e);
string_burn(n);
string_free(n);
return rc;
}
static int dsa_public_to_string(gcry_sexp_t key, ssh_buffer buffer) {
#elif defined HAVE_LIBCRYPTO
static int dsa_public_to_string(DSA *key, ssh_buffer buffer) {
#endif
ssh_string p = NULL;
ssh_string q = NULL;
ssh_string g = NULL;
ssh_string n = NULL;
int rc = -1;
#ifdef HAVE_LIBGCRYPT
const char *tmp = NULL;
size_t size;
gcry_sexp_t sexp;
sexp = gcry_sexp_find_token(key, "p", 0);
if (sexp == NULL) {
goto error;
}
tmp = gcry_sexp_nth_data(sexp, 1, &size);
p = string_new(size);
if (p == NULL) {
goto error;
}
string_fill(p, (char *) tmp, size);
gcry_sexp_release(sexp);
sexp = gcry_sexp_find_token(key, "q", 0);
if (sexp == NULL) {
goto error;
}
tmp = gcry_sexp_nth_data(sexp, 1, &size);
q = string_new(size);
if (q == NULL) {
goto error;
}
string_fill(q, (char *) tmp, size);
gcry_sexp_release(sexp);
sexp = gcry_sexp_find_token(key, "g", 0);
if (sexp == NULL) {
goto error;
}
tmp = gcry_sexp_nth_data(sexp, 1, &size);
g = string_new(size);
if (g == NULL) {
goto error;
}
string_fill(g, (char *) tmp, size);
gcry_sexp_release(sexp);
sexp = gcry_sexp_find_token(key, "y", 0);
if (sexp == NULL) {
goto error;
}
tmp = gcry_sexp_nth_data(sexp, 1, &size);
n = string_new(size);
if (n == NULL) {
goto error;
}
string_fill(n, (char *) tmp, size);
#elif defined HAVE_LIBCRYPTO
p = make_bignum_string(key->p);
q = make_bignum_string(key->q);
g = make_bignum_string(key->g);
n = make_bignum_string(key->pub_key);
if (p == NULL || q == NULL || g == NULL || n == NULL) {
goto error;
}
#endif /* HAVE_LIBCRYPTO */
if (buffer_add_ssh_string(buffer, p) < 0) {
goto error;
}
if (buffer_add_ssh_string(buffer, q) < 0) {
goto error;
}
if (buffer_add_ssh_string(buffer, g) < 0) {
goto error;
}
if (buffer_add_ssh_string(buffer, n) < 0) {
goto error;
}
rc = 0;
error:
#ifdef HAVE_LIBGCRYPT
gcry_sexp_release(sexp);
#endif
string_burn(p);
string_free(p);
string_burn(q);
string_free(q);
string_burn(g);
string_free(g);
string_burn(n);
string_free(n);
return rc;
}
/** \brief Makes a PUBLIC_KEY object out of a PRIVATE_KEY object
* \param prv the Private key
* \returns the public key
* \see publickey_to_string()
*/
ssh_public_key publickey_from_privatekey(ssh_private_key prv) {
ssh_public_key key = NULL;
#ifdef HAVE_LIBGCRYPT
gcry_sexp_t sexp;
const char *tmp = NULL;
size_t size;
ssh_string p = NULL;
ssh_string q = NULL;
ssh_string g = NULL;
ssh_string y = NULL;
ssh_string e = NULL;
ssh_string n = NULL;
#endif /* HAVE_LIBGCRYPT */
key = malloc(sizeof(struct ssh_public_key_struct));
if (key == NULL) {
return NULL;
}
key->type = prv->type;
switch(key->type) {
case TYPE_DSS:
#ifdef HAVE_LIBGCRYPT
sexp = gcry_sexp_find_token(prv->dsa_priv, "p", 0);
if (sexp == NULL) {
goto error;
}
tmp = gcry_sexp_nth_data(sexp, 1, &size);
p = string_new(size);
if (p == NULL) {
goto error;
}
string_fill(p,(char *) tmp, size);
gcry_sexp_release(sexp);
sexp = gcry_sexp_find_token(prv->dsa_priv,"q",0);
if (sexp == NULL) {
goto error;
}
tmp = gcry_sexp_nth_data(sexp,1,&size);
q = string_new(size);
if (q == NULL) {
goto error;
}
string_fill(q,(char *) tmp,size);
gcry_sexp_release(sexp);
sexp = gcry_sexp_find_token(prv->dsa_priv, "g", 0);
if (sexp == NULL) {
goto error;
}
tmp = gcry_sexp_nth_data(sexp,1,&size);
g = string_new(size);
if (g == NULL) {
goto error;
}
string_fill(g,(char *) tmp,size);
gcry_sexp_release(sexp);
sexp = gcry_sexp_find_token(prv->dsa_priv,"y",0);
if (sexp == NULL) {
goto error;
}
tmp = gcry_sexp_nth_data(sexp,1,&size);
y = string_new(size);
if (y == NULL) {
goto error;
}
string_fill(y,(char *) tmp,size);
gcry_sexp_release(sexp);
gcry_sexp_build(&key->dsa_pub, NULL,
"(public-key(dsa(p %b)(q %b)(g %b)(y %b)))",
string_len(p), string_data(p),
string_len(q), string_data(q),
string_len(g), string_data(g),
string_len(y), string_data(y));
string_burn(p);
string_free(p);
string_burn(q);
string_free(q);
string_burn(g);
string_free(g);
string_burn(y);
string_free(y);
#elif defined HAVE_LIBCRYPTO
key->dsa_pub = DSA_new();
if (key->dsa_pub == NULL) {
goto error;
}
key->dsa_pub->p = BN_dup(prv->dsa_priv->p);
key->dsa_pub->q = BN_dup(prv->dsa_priv->q);
key->dsa_pub->g = BN_dup(prv->dsa_priv->g);
key->dsa_pub->pub_key = BN_dup(prv->dsa_priv->pub_key);
if (key->dsa_pub->p == NULL ||
key->dsa_pub->q == NULL ||
key->dsa_pub->g == NULL ||
key->dsa_pub->pub_key == NULL) {
goto error;
}
#endif /* HAVE_LIBCRYPTO */
break;
case TYPE_RSA:
case TYPE_RSA1:
#ifdef HAVE_LIBGCRYPT
sexp = gcry_sexp_find_token(prv->rsa_priv, "n", 0);
if (sexp == NULL) {
goto error;
}
tmp = gcry_sexp_nth_data(sexp, 1, &size);
n = string_new(size);
if (n == NULL) {
goto error;
}
string_fill(n, (char *) tmp, size);
gcry_sexp_release(sexp);
sexp = gcry_sexp_find_token(prv->rsa_priv, "e", 0);
if (sexp == NULL) {
goto error;
}
tmp = gcry_sexp_nth_data(sexp, 1, &size);
e = string_new(size);
if (e == NULL) {
goto error;
}
string_fill(e, (char *) tmp, size);
gcry_sexp_release(sexp);
gcry_sexp_build(&key->rsa_pub, NULL,
"(public-key(rsa(n %b)(e %b)))",
string_len(n), string_data(n),
string_len(e), string_data(e));
if (key->rsa_pub == NULL) {
goto error;
}
string_burn(e);
string_free(e);
string_burn(n);
string_free(n);
#elif defined HAVE_LIBCRYPTO
key->rsa_pub = RSA_new();
if (key->rsa_pub == NULL) {
goto error;
}
key->rsa_pub->e = BN_dup(prv->rsa_priv->e);
key->rsa_pub->n = BN_dup(prv->rsa_priv->n);
if (key->rsa_pub->e == NULL ||
key->rsa_pub->n == NULL) {
goto error;
}
#endif
break;
}
key->type_c = ssh_type_to_char(prv->type);
return key;
error:
#ifdef HAVE_LIBGCRYPT
gcry_sexp_release(sexp);
string_burn(p);
string_free(p);
string_burn(q);
string_free(q);
string_burn(g);
string_free(g);
string_burn(y);
string_free(y);
string_burn(e);
string_free(e);
string_burn(n);
string_free(n);
#endif
publickey_free(key);
return NULL;
}
ssh_public_key publickey_make_rsa(ssh_session session, ssh_buffer buffer,
int type) {
ssh_string e = NULL;
ssh_string n = NULL;
ssh_public_key key = NULL;
key = malloc(sizeof(struct ssh_public_key_struct));
if (key == NULL) {
buffer_free(buffer);
return NULL;
}
key->type = type;
key->type_c = ssh_type_to_char(key->type);
e = buffer_get_ssh_string(buffer);
n = buffer_get_ssh_string(buffer);
buffer_free(buffer); /* we don't need it anymore */
if(e == NULL || n == NULL) {
ssh_set_error(session, SSH_FATAL, "Invalid RSA public key");
goto error;
}
#ifdef HAVE_LIBGCRYPT
gcry_sexp_build(&key->rsa_pub, NULL,
"(public-key(rsa(n %b)(e %b)))",
string_len(n), string_data(n),
string_len(e),string_data(e));
if (key->rsa_pub == NULL) {
goto error;
}
#elif HAVE_LIBCRYPTO
key->rsa_pub = RSA_new();
if (key->rsa_pub == NULL) {
goto error;
}
key->rsa_pub->e = make_string_bn(e);
key->rsa_pub->n = make_string_bn(n);
if (key->rsa_pub->e == NULL ||
key->rsa_pub->n == NULL) {
goto error;
}
#endif
#ifdef DEBUG_CRYPTO
ssh_print_hexa("e", string_data(e), string_len(e));
ssh_print_hexa("n", string_data(n), string_len(n));
#endif
string_burn(e);
string_free(e);
string_burn(n);
string_free(n);
return key;
error:
string_burn(e);
string_free(e);
string_burn(n);
string_free(n);
publickey_free(key);
return NULL;
}
PUBLIC_KEY *publickey_make_dss(SSH_SESSION *session, BUFFER *buffer) {
STRING *p = NULL;
STRING *q = NULL;
STRING *g = NULL;
STRING *pubkey = NULL;
PUBLIC_KEY *key = NULL;
key = malloc(sizeof(PUBLIC_KEY));
if (key == NULL) {
buffer_free(buffer);
return NULL;
}
key->type = TYPE_DSS;
key->type_c = ssh_type_to_char(key->type);
p = buffer_get_ssh_string(buffer);
q = buffer_get_ssh_string(buffer);
g = buffer_get_ssh_string(buffer);
pubkey = buffer_get_ssh_string(buffer);
buffer_free(buffer); /* we don't need it anymore */
if (p == NULL || q == NULL || g == NULL || pubkey == NULL) {
ssh_set_error(session, SSH_FATAL, "Invalid DSA public key");
goto error;
}
#ifdef HAVE_LIBGCRYPT
gcry_sexp_build(&key->dsa_pub, NULL,
"(public-key(dsa(p %b)(q %b)(g %b)(y %b)))",
string_len(p), p->string,
string_len(q), q->string,
string_len(g), g->string,
string_len(pubkey), pubkey->string);
if (key->dsa_pub == NULL) {
goto error;
}
#elif defined HAVE_LIBCRYPTO
key->dsa_pub = DSA_new();
if (key->dsa_pub == NULL) {
goto error;
}
key->dsa_pub->p = make_string_bn(p);
key->dsa_pub->q = make_string_bn(q);
key->dsa_pub->g = make_string_bn(g);
key->dsa_pub->pub_key = make_string_bn(pubkey);
if (key->dsa_pub->p == NULL ||
key->dsa_pub->q == NULL ||
key->dsa_pub->g == NULL ||
key->dsa_pub->pub_key == NULL) {
goto error;
}
#endif /* HAVE_LIBCRYPTO */
#ifdef DEBUG_CRYPTO
ssh_print_hexa("p", p->string, string_len(p));
ssh_print_hexa("q", q->string, string_len(q));
ssh_print_hexa("g", g->string, string_len(g));
#endif
string_burn(p);
string_free(p);
string_burn(q);
string_free(q);
string_burn(g);
string_free(g);
string_burn(pubkey);
string_free(pubkey);
return key;
error:
string_burn(p);
string_free(p);
string_burn(q);
string_free(q);
string_burn(g);
string_free(g);
string_burn(pubkey);
string_free(pubkey);
publickey_free(key);
return NULL;
}
PUBLIC_KEY *publickey_make_rsa(SSH_SESSION *session, BUFFER *buffer,
int type) {
STRING *e = NULL;
STRING *n = NULL;
PUBLIC_KEY *key = NULL;
key = malloc(sizeof(PUBLIC_KEY));
if (key == NULL) {
buffer_free(buffer);
return NULL;
}
key->type = type;
key->type_c = ssh_type_to_char(key->type);
e = buffer_get_ssh_string(buffer);
n = buffer_get_ssh_string(buffer);
buffer_free(buffer); /* we don't need it anymore */
if(e == NULL || n == NULL) {
ssh_set_error(session, SSH_FATAL, "Invalid RSA public key");
goto error;
}
#ifdef HAVE_LIBGCRYPT
gcry_sexp_build(&key->rsa_pub, NULL,
"(public-key(rsa(n %b)(e %b)))",
string_len(n), n->string,
string_len(e),e->string);
if (key->rsa_pub == NULL) {
goto error;
}
#elif HAVE_LIBCRYPTO
key->rsa_pub = RSA_new();
if (key->rsa_pub == NULL) {
goto error;
}
key->rsa_pub->e = make_string_bn(e);
key->rsa_pub->n = make_string_bn(n);
if (key->rsa_pub->e == NULL ||
key->rsa_pub->n == NULL) {
goto error;
}
#endif
#ifdef DEBUG_CRYPTO
ssh_print_hexa("e", e->string, string_len(e));
ssh_print_hexa("n", n->string, string_len(n));
#endif
string_burn(e);
string_free(e);
string_burn(n);
string_free(n);
return key;
error:
string_burn(e);
string_free(e);
string_burn(n);
string_free(n);
publickey_free(key);
return NULL;
}
/**
* @brief Try to authenticate by password.
*
* @param session The ssh session to use.
*
* @param username The username to authenticate. You can specify NULL if
* ssh_option_set_username() has been used. You cannot try
* two different logins in a row.
*
* @param password The password to use. Take care to clean it after
* the authentication.
*
* @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 successful.
*
* @see ssh_userauth_kbdint()
* @see BURN_STRING
*/
int ssh_userauth_password(ssh_session session, const char *username,
const char *password) {
ssh_string user = NULL;
ssh_string service = NULL;
ssh_string method = NULL;
ssh_string pwd = NULL;
int rc = SSH_AUTH_ERROR;
enter_function();
#ifdef WITH_SSH1
if (session->version == 1) {
rc = ssh_userauth1_password(session, username, password);
leave_function();
return rc;
}
#endif
if (username == NULL) {
if (session->username == NULL) {
if (ssh_options_apply(session) < 0) {
leave_function();
return rc;
}
}
user = string_from_char(session->username);
} else {
user = string_from_char(username);
}
if (user == NULL) {
leave_function();
return rc;
}
if (ask_userauth(session) < 0) {
string_free(user);
leave_function();
return rc;
}
service = string_from_char("ssh-connection");
if (service == NULL) {
goto error;
}
method = string_from_char("password");
if (method == NULL) {
goto error;
}
pwd = string_from_char(password);
if (pwd == NULL) {
goto error;
}
if (buffer_add_u8(session->out_buffer, SSH2_MSG_USERAUTH_REQUEST) < 0 ||
buffer_add_ssh_string(session->out_buffer, user) < 0 ||
buffer_add_ssh_string(session->out_buffer, service) < 0 ||
buffer_add_ssh_string(session->out_buffer, method) < 0 ||
buffer_add_u8(session->out_buffer, 0) < 0 ||
buffer_add_ssh_string(session->out_buffer, pwd) < 0) {
goto error;
}
string_free(user);
string_free(service);
string_free(method);
string_burn(pwd);
string_free(pwd);
if (packet_send(session) != SSH_OK) {
leave_function();
return rc;
}
rc = wait_auth_status(session, 0);
leave_function();
return rc;
error:
buffer_reinit(session->out_buffer);
string_free(user);
string_free(service);
string_free(method);
string_burn(pwd);
string_free(pwd);
leave_function();
return rc;
}
