static int build_session_id1(ssh_session session, ssh_string servern,
ssh_string hostn) {
MD5CTX md5 = NULL;
md5 = md5_init();
if (md5 == NULL) {
return -1;
}
#ifdef DEBUG_CRYPTO
ssh_print_hexa("host modulus",ssh_string_data(hostn),ssh_string_len(hostn));
ssh_print_hexa("server modulus",ssh_string_data(servern),ssh_string_len(servern));
#endif
md5_update(md5,ssh_string_data(hostn),ssh_string_len(hostn));
md5_update(md5,ssh_string_data(servern),ssh_string_len(servern));
md5_update(md5,session->next_crypto->server_kex.cookie,8);
if(session->next_crypto->session_id != NULL)
SAFE_FREE(session->next_crypto->session_id);
session->next_crypto->session_id = malloc(MD5_DIGEST_LEN);
if(session->next_crypto->session_id == NULL){
ssh_set_error_oom(session);
return SSH_ERROR;
}
md5_final(session->next_crypto->session_id,md5);
#ifdef DEBUG_CRYPTO
ssh_print_hexa("session_id",session->next_crypto->session_id,MD5_DIGEST_LEN);
#endif
return 0;
}
static ssh_string make_ecpoint_string(const EC_GROUP *g,
const EC_POINT *p)
{
ssh_string s;
size_t len;
len = EC_POINT_point2oct(g,
p,
POINT_CONVERSION_UNCOMPRESSED,
NULL,
0,
NULL);
if (len == 0) {
return NULL;
}
s = ssh_string_new(len);
if (s == NULL) {
return NULL;
}
len = EC_POINT_point2oct(g,
p,
POINT_CONVERSION_UNCOMPRESSED,
ssh_string_data(s),
ssh_string_len(s),
NULL);
if (len != ssh_string_len(s)) {
ssh_string_free(s);
return NULL;
}
return s;
}
int pki_privkey_build_rsa(ssh_key key,
ssh_string n,
ssh_string e,
ssh_string d,
ssh_string iqmp,
ssh_string p,
ssh_string q)
{
mbedtls_rsa_context *rsa = NULL;
const mbedtls_pk_info_t *pk_info = NULL;
int rc;
key->rsa = malloc(sizeof(mbedtls_pk_context));
if (key->rsa == NULL) {
return SSH_ERROR;
}
mbedtls_pk_init(key->rsa);
pk_info = mbedtls_pk_info_from_type(MBEDTLS_PK_RSA);
mbedtls_pk_setup(key->rsa, pk_info);
rc = mbedtls_pk_can_do(key->rsa, MBEDTLS_PK_RSA);
if (rc == 0) {
goto fail;
}
rsa = mbedtls_pk_rsa(*key->rsa);
rc = mbedtls_rsa_import_raw(rsa,
ssh_string_data(n), ssh_string_len(n),
ssh_string_data(p), ssh_string_len(p),
ssh_string_data(q), ssh_string_len(q),
ssh_string_data(d), ssh_string_len(d),
ssh_string_data(e), ssh_string_len(e));
if (rc != 0) {
SSH_LOG(SSH_LOG_WARN, "Failed to import private RSA key");
goto fail;
}
rc = mbedtls_rsa_complete(rsa);
if (rc != 0) {
SSH_LOG(SSH_LOG_WARN, "Failed to complete private RSA key");
goto fail;
}
rc = mbedtls_rsa_check_privkey(rsa);
if (rc != 0) {
SSH_LOG(SSH_LOG_WARN, "Inconsistent private RSA key");
goto fail;
}
return SSH_OK;
fail:
mbedtls_pk_free(key->rsa);
SAFE_FREE(key->rsa);
return SSH_ERROR;
}
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);
}
/** @internal
* @brief parses a SSH_MSG_KEX_ECDH_REPLY packet and sends back
* a SSH_MSG_NEWKEYS
*/
int ssh_client_curve25519_reply(ssh_session_t * session, ssh_buffer_t * packet){
ssh_string_t * q_s_string = NULL;
ssh_string_t * pubkey = NULL;
ssh_string_t * signature = NULL;
int rc;
pubkey = buffer_get_ssh_string(packet);
if (pubkey == NULL){
ssh_set_error(session,SSH_FATAL, "No public key in packet");
goto error;
}
/* this is the server host key */
session->next_crypto->server_pubkey = pubkey;
pubkey = NULL;
q_s_string = buffer_get_ssh_string(packet);
if (q_s_string == NULL) {
ssh_set_error(session,SSH_FATAL, "No Q_S ECC point in packet");
goto error;
}
if (ssh_string_len(q_s_string) != CURVE25519_PUBKEY_SIZE){
ssh_set_error(session, SSH_FATAL, "Incorrect size for server Curve25519 public key: %d",
(int)ssh_string_len(q_s_string));
ssh_string_free(q_s_string);
goto error;
}
memcpy(session->next_crypto->curve25519_server_pubkey, ssh_string_data(q_s_string), CURVE25519_PUBKEY_SIZE);
ssh_string_free(q_s_string);
signature = buffer_get_ssh_string(packet);
if (signature == NULL) {
ssh_set_error(session, SSH_FATAL, "No signature in packet");
goto error;
}
session->next_crypto->dh_server_signature = signature;
signature=NULL; /* ownership changed */
/* TODO: verify signature now instead of waiting for NEWKEYS */
if (ssh_curve25519_build_k(session) < 0) {
ssh_set_error(session, SSH_FATAL, "Cannot build k number");
goto error;
}
/* Send the MSG_NEWKEYS */
if (buffer_add_u8(session->out_buffer, SSH2_MSG_NEWKEYS) < 0) {
goto error;
}
rc=packet_send(session);
SSH_INFO(SSH_LOG_PROTOCOL, "SSH_MSG_NEWKEYS sent");
return rc;
error:
return SSH_ERROR;
}
int pki_pubkey_build_rsa(ssh_key key,
ssh_string e,
ssh_string n) {
gcry_sexp_build(&key->rsa, NULL,
"(public-key(rsa(n %b)(e %b)))",
ssh_string_len(n), ssh_string_data(n),
ssh_string_len(e),ssh_string_data(e));
if (key->rsa == NULL) {
return SSH_ERROR;
}
return SSH_OK;
}
static int ecdh_build_k(ssh_session session) {
const EC_GROUP *group = EC_KEY_get0_group(session->next_crypto->ecdh_privkey);
EC_POINT *pubkey;
void *buffer;
int len = (EC_GROUP_get_degree(group) + 7) / 8;
bignum_CTX ctx = bignum_ctx_new();
if (ctx == NULL) {
return -1;
}
session->next_crypto->k = bignum_new();
if (session->next_crypto->k == NULL) {
bignum_ctx_free(ctx);
return -1;
}
pubkey = EC_POINT_new(group);
if (pubkey == NULL) {
bignum_ctx_free(ctx);
return -1;
}
if (session->server)
EC_POINT_oct2point(group,pubkey,ssh_string_data(session->next_crypto->ecdh_client_pubkey),
ssh_string_len(session->next_crypto->ecdh_client_pubkey),ctx);
else
EC_POINT_oct2point(group,pubkey,ssh_string_data(session->next_crypto->ecdh_server_pubkey),
ssh_string_len(session->next_crypto->ecdh_server_pubkey),ctx);
buffer = malloc(len);
ECDH_compute_key(buffer,len,pubkey,session->next_crypto->ecdh_privkey,NULL);
EC_POINT_free(pubkey);
BN_bin2bn(buffer,len,session->next_crypto->k);
free(buffer);
EC_KEY_free(session->next_crypto->ecdh_privkey);
session->next_crypto->ecdh_privkey=NULL;
#ifdef DEBUG_CRYPTO
ssh_print_hexa("Session server cookie",
session->next_crypto->server_kex.cookie, 16);
ssh_print_hexa("Session client cookie",
session->next_crypto->client_kex.cookie, 16);
ssh_print_bignum("Shared secret key", session->next_crypto->k);
#endif
#ifdef HAVE_LIBCRYPTO
bignum_ctx_free(ctx);
#endif
return 0;
}
/**
* @deprecated Use ssh_get_publickey_hash()
*/
int ssh_get_pubkey_hash(ssh_session session, unsigned char **hash) {
ssh_string pubkey;
MD5CTX ctx;
unsigned char *h;
if (session == NULL || hash == NULL) {
return SSH_ERROR;
}
*hash = NULL;
if (session->current_crypto == NULL ||
session->current_crypto->server_pubkey == NULL){
ssh_set_error(session,SSH_FATAL,"No current cryptographic context");
return SSH_ERROR;
}
h = malloc(sizeof(unsigned char) * MD5_DIGEST_LEN);
if (h == NULL) {
return SSH_ERROR;
}
ctx = md5_init();
if (ctx == NULL) {
SAFE_FREE(h);
return SSH_ERROR;
}
pubkey = session->current_crypto->server_pubkey;
md5_update(ctx, ssh_string_data(pubkey), ssh_string_len(pubkey));
md5_final(h, ctx);
*hash = h;
return MD5_DIGEST_LEN;
}
/**
* @brief Convert a public key to a base64 encoded key.
*
* @param[in] key The key to hash
*
* @param[out] b64_key A pointer to store the allocated base64 encoded key. You
* need to free the buffer.
*
* @return SSH_OK on success, SSH_ERROR on error.
*
* @see ssh_string_free_char()
*/
int ssh_pki_export_pubkey_base64(const ssh_key key,
char **b64_key)
{
ssh_string key_blob;
unsigned char *b64;
if (key == NULL || b64_key == NULL) {
return SSH_ERROR;
}
key_blob = pki_publickey_to_blob(key);
if (key_blob == NULL) {
return SSH_ERROR;
}
b64 = bin_to_base64(ssh_string_data(key_blob), ssh_string_len(key_blob));
ssh_string_free(key_blob);
if (b64 == NULL) {
return SSH_ERROR;
}
*b64_key = (char *)b64;
return SSH_OK;
}
int pki_pubkey_build_dss(ssh_key key,
ssh_string p,
ssh_string q,
ssh_string g,
ssh_string pubkey) {
gcry_sexp_build(&key->dsa, NULL,
"(public-key(dsa(p %b)(q %b)(g %b)(y %b)))",
ssh_string_len(p), ssh_string_data(p),
ssh_string_len(q), ssh_string_data(q),
ssh_string_len(g), ssh_string_data(g),
ssh_string_len(pubkey), ssh_string_data(pubkey));
if (key->dsa == NULL) {
return SSH_ERROR;
}
return SSH_OK;
}
void make_string_bn_inplace(ssh_string string, bignum bnout) {
unsigned int len = ssh_string_len(string);
#ifdef HAVE_LIBGCRYPT
/* XXX: FIXME as needed for LIBGCRYPT ECDSA codepaths. */
(void) len;
(void) bnout;
#elif defined HAVE_LIBCRYPTO
bignum_bin2bn(string->data, len, bnout);
#endif
}
int pki_pubkey_build_rsa(ssh_key key, ssh_string e, ssh_string n)
{
mbedtls_rsa_context *rsa = NULL;
const mbedtls_pk_info_t *pk_info = NULL;
int rc;
key->rsa = malloc(sizeof(mbedtls_pk_context));
if (key->rsa == NULL) {
return SSH_ERROR;
}
mbedtls_pk_init(key->rsa);
pk_info = mbedtls_pk_info_from_type(MBEDTLS_PK_RSA);
mbedtls_pk_setup(key->rsa, pk_info);
rc = mbedtls_pk_can_do(key->rsa, MBEDTLS_PK_RSA);
if (rc == 0) {
goto fail;
}
rsa = mbedtls_pk_rsa(*key->rsa);
rc = mbedtls_mpi_read_binary(&rsa->N, ssh_string_data(n),
ssh_string_len(n));
if (rc != 0) {
goto fail;
}
rc = mbedtls_mpi_read_binary(&rsa->E, ssh_string_data(e),
ssh_string_len(e));
if (rc != 0) {
goto fail;
}
rsa->len = (mbedtls_mpi_bitlen(&rsa->N) + 7) >> 3;
return SSH_OK;
fail:
mbedtls_pk_free(key->rsa);
SAFE_FREE(key->rsa);
return SSH_ERROR;
}
/**
* @internal
*
* @brief Import a public key from a ssh string.
*
* @param[in] key_blob The key blob to import as specified in RFC 4253 section
* 6.6 "Public Key Algorithms".
*
* @param[out] pkey A pointer where the allocated key can be stored. You
* need to free the memory.
*
* @return SSH_OK on success, SSH_ERROR on error.
*
* @see ssh_key_free()
*/
int ssh_pki_import_pubkey_blob(const ssh_string key_blob,
ssh_key *pkey) {
ssh_buffer buffer;
ssh_string type_s = NULL;
enum ssh_keytypes_e type;
int rc;
if (key_blob == NULL || pkey == NULL) {
return SSH_ERROR;
}
buffer = ssh_buffer_new();
if (buffer == NULL) {
SSH_LOG(SSH_LOG_WARN, "Out of memory!");
return SSH_ERROR;
}
rc = ssh_buffer_add_data(buffer, ssh_string_data(key_blob),
ssh_string_len(key_blob));
if (rc < 0) {
SSH_LOG(SSH_LOG_WARN, "Out of memory!");
goto fail;
}
type_s = ssh_buffer_get_ssh_string(buffer);
if (type_s == NULL) {
SSH_LOG(SSH_LOG_WARN, "Out of memory!");
goto fail;
}
type = ssh_key_type_from_name(ssh_string_get_char(type_s));
if (type == SSH_KEYTYPE_UNKNOWN) {
SSH_LOG(SSH_LOG_WARN, "Unknown key type found!");
goto fail;
}
ssh_string_free(type_s);
if (type == SSH_KEYTYPE_RSA_CERT01 ||
type == SSH_KEYTYPE_DSS_CERT01) {
rc = pki_import_cert_buffer(buffer, type, pkey);
} else {
rc = pki_import_pubkey_buffer(buffer, type, pkey);
}
ssh_buffer_free(buffer);
return rc;
fail:
ssh_buffer_free(buffer);
ssh_string_free(type_s);
return SSH_ERROR;
}
int ssh_pki_import_signature_blob(const ssh_string sig_blob,
const ssh_key pubkey,
ssh_signature *psig)
{
ssh_signature sig;
enum ssh_keytypes_e type;
ssh_string str;
ssh_buffer buf;
int rc;
if (sig_blob == NULL || psig == NULL) {
return SSH_ERROR;
}
buf = ssh_buffer_new();
if (buf == NULL) {
return SSH_ERROR;
}
rc = ssh_buffer_add_data(buf,
ssh_string_data(sig_blob),
ssh_string_len(sig_blob));
if (rc < 0) {
ssh_buffer_free(buf);
return SSH_ERROR;
}
str = ssh_buffer_get_ssh_string(buf);
if (str == NULL) {
ssh_buffer_free(buf);
return SSH_ERROR;
}
type = ssh_key_type_from_name(ssh_string_get_char(str));
ssh_string_free(str);
str = ssh_buffer_get_ssh_string(buf);
ssh_buffer_free(buf);
if (str == NULL) {
return SSH_ERROR;
}
sig = pki_signature_from_blob(pubkey, str, type);
ssh_string_free(str);
if (sig == NULL) {
return SSH_ERROR;
}
*psig = sig;
return SSH_OK;
}
static int generate_one_key(ssh_string k,
struct ssh_crypto_struct *crypto, unsigned char **output, char letter, size_t requested_size) {
ssh_mac_ctx ctx;
unsigned char *tmp;
size_t size = crypto->digest_len;
ctx=ssh_mac_ctx_init(crypto->mac_type);
if (ctx == NULL) {
return -1;
}
ssh_mac_update(ctx, k, ssh_string_len(k) + 4);
ssh_mac_update(ctx, crypto->secret_hash, crypto->digest_len);
ssh_mac_update(ctx, &letter, 1);
ssh_mac_update(ctx, crypto->session_id, crypto->digest_len);
ssh_mac_final(*output, ctx);
while(requested_size > size) {
tmp = realloc(*output, size + crypto->digest_len);
if (tmp == NULL) {
return -1;
}
*output = tmp;
ctx = ssh_mac_ctx_init(crypto->mac_type);
if (ctx == NULL) {
return -1;
}
ssh_mac_update(ctx, k, ssh_string_len(k) + 4);
ssh_mac_update(ctx, crypto->secret_hash,
crypto->digest_len);
ssh_mac_update(ctx, tmp, size);
ssh_mac_final(tmp + size, ctx);
size += crypto->digest_len;
}
return 0;
}
bignum ssh_make_string_bn(ssh_string string)
{
bignum bn = NULL;
size_t len = ssh_string_len(string);
#ifdef DEBUG_CRYPTO
fprintf(stderr, "Importing a %zu bits, %zu bytes object ...\n",
len * 8, len);
#endif /* DEBUG_CRYPTO */
bignum_bin2bn(string->data, len, &bn);
return bn;
}
/**
* @brief Export a private key to a pem file on disk, or OpenSSH format for
* keytype ssh-ed25519
*
* @param[in] privkey The private key to export.
*
* @param[in] passphrase The passphrase to use to encrypt the key with or
* NULL. An empty string means no passphrase.
*
* @param[in] auth_fn An auth function you may want to use or NULL.
*
* @param[in] auth_data Private data passed to the auth function.
*
* @param[in] filename The path where to store the pem file.
*
* @return SSH_OK on success, SSH_ERROR on error.
*/
int ssh_pki_export_privkey_file(const ssh_key privkey,
const char *passphrase,
ssh_auth_callback auth_fn,
void *auth_data,
const char *filename)
{
ssh_string blob;
FILE *fp;
int rc;
if (privkey == NULL || !ssh_key_is_private(privkey)) {
return SSH_ERROR;
}
fp = fopen(filename, "wb");
if (fp == NULL) {
SSH_LOG(SSH_LOG_FUNCTIONS, "Error opening %s: %s",
filename, strerror(errno));
return SSH_EOF;
}
if (privkey->type == SSH_KEYTYPE_ED25519){
blob = ssh_pki_openssh_privkey_export(privkey,
passphrase,
auth_fn,
auth_data);
} else {
blob = pki_private_key_to_pem(privkey,
passphrase,
auth_fn,
auth_data);
}
if (blob == NULL) {
fclose(fp);
return -1;
}
rc = fwrite(ssh_string_data(blob), ssh_string_len(blob), 1, fp);
ssh_string_free(blob);
if (rc != 1 || ferror(fp)) {
fclose(fp);
unlink(filename);
return SSH_ERROR;
}
fclose(fp);
return SSH_OK;
}
bignum make_string_bn(ssh_string string){
bignum bn = NULL;
unsigned int len = ssh_string_len(string);
#ifdef DEBUG_CRYPTO
fprintf(stderr, "Importing a %d bits, %d bytes object ...\n",
len * 8, len);
#endif /* DEBUG_CRYPTO */
#ifdef HAVE_LIBGCRYPT
bignum_bin2bn(string->data, len, &bn);
#elif defined HAVE_LIBCRYPTO
bn = bignum_bin2bn(string->data, len, NULL);
#endif
return bn;
}
/*
* This function signs the session id (known as H) as a string then
* the content of sigbuf */
ssh_string ssh_pki_do_sign(ssh_session session, ssh_buffer sigbuf,
ssh_key privatekey) {
struct ssh_crypto_struct *crypto = session->current_crypto ? session->current_crypto :
session->next_crypto;
unsigned char hash[SHA_DIGEST_LEN + 1] = {0};
ssh_string session_str = NULL;
ssh_string signature = NULL;
struct signature_struct *sign = NULL;
SHACTX ctx = NULL;
if (privatekey == NULL || !ssh_key_is_private(privatekey)) {
return NULL;
}
session_str = ssh_string_new(SHA_DIGEST_LEN);
if (session_str == NULL) {
return NULL;
}
ssh_string_fill(session_str, crypto->session_id, SHA_DIGEST_LEN);
ctx = sha1_init();
if (ctx == NULL) {
ssh_string_free(session_str);
return NULL;
}
sha1_update(ctx, session_str, ssh_string_len(session_str) + 4);
ssh_string_free(session_str);
sha1_update(ctx, buffer_get_rest(sigbuf), buffer_get_rest_len(sigbuf));
sha1_final(hash + 1,ctx);
hash[0] = 0;
#ifdef DEBUG_CRYPTO
ssh_print_hexa("Hash being signed with dsa", hash + 1, SHA_DIGEST_LEN);
#endif
sign = pki_do_sign(privatekey, hash);
if (sign == NULL) {
return NULL;
}
signature = signature_to_string(sign);
signature_free(sign);
return signature;
}
static gss_OID ssh_gssapi_oid_from_string(ssh_string oid_s){
gss_OID ret = malloc(sizeof (gss_OID_desc));
unsigned char *data = ssh_string_data(oid_s);
size_t len = ssh_string_len(oid_s);
if(len > 256 || len <= 2){
SAFE_FREE(ret);
return NULL;
}
if(data[0] != SSH_OID_TAG || data[1] != len - 2){
SAFE_FREE(ret);
return NULL;
}
ret->elements = malloc(len - 2);
memcpy(ret->elements, &data[2], len-2);
ret->length = len-2;
return ret;
}
ssh_public_key publickey_from_string(ssh_session session, ssh_string pubkey_s) {
ssh_buffer tmpbuf = NULL;
ssh_string type_s = NULL;
char *type_c = NULL;
int type;
tmpbuf = ssh_buffer_new();
if (tmpbuf == NULL) {
return NULL;
}
if (buffer_add_data(tmpbuf, ssh_string_data(pubkey_s), ssh_string_len(pubkey_s)) < 0) {
goto error;
}
type_s = buffer_get_ssh_string(tmpbuf);
if (type_s == NULL) {
ssh_set_error(session,SSH_FATAL,"Invalid public key format");
goto error;
}
type_c = ssh_string_to_char(type_s);
ssh_string_free(type_s);
if (type_c == NULL) {
goto error;
}
type = ssh_type_from_name(type_c);
SAFE_FREE(type_c);
switch (type) {
case SSH_KEYTYPE_DSS:
return publickey_make_dss(session, tmpbuf);
case SSH_KEYTYPE_RSA:
case SSH_KEYTYPE_RSA1:
return publickey_make_rsa(session, tmpbuf, type);
}
ssh_set_error(session, SSH_FATAL, "Unknown public key protocol %s",
ssh_type_to_char(type));
error:
ssh_buffer_free(tmpbuf);
return NULL;
}
void *sftp_handle(sftp_session sftp, ssh_string handle){
uint32_t val;
if (sftp->handles == NULL) {
return NULL;
}
if (ssh_string_len(handle) != sizeof(uint32_t)) {
return NULL;
}
memcpy(&val, ssh_string_data(handle), sizeof(uint32_t));
if (val > SFTP_HANDLES) {
return NULL;
}
return sftp->handles[val];
}
static int generate_one_key(ssh_string k,
unsigned char session_id[SHA_DIGEST_LEN],
unsigned char output[SHA_DIGEST_LEN],
char letter) {
SHACTX ctx = NULL;
ctx = sha1_init();
if (ctx == NULL) {
return -1;
}
sha1_update(ctx, k, ssh_string_len(k) + 4);
sha1_update(ctx, session_id, SHA_DIGEST_LEN);
sha1_update(ctx, &letter, 1);
sha1_update(ctx, session_id, SHA_DIGEST_LEN);
sha1_final(output, ctx);
return 0;
}
int pki_pubkey_build_ecdsa(ssh_key key, int nid, ssh_string e)
{
EC_POINT *p;
const EC_GROUP *g;
int ok;
key->ecdsa_nid = nid;
key->type_c = pki_key_ecdsa_nid_to_name(nid);
key->ecdsa = EC_KEY_new_by_curve_name(key->ecdsa_nid);
if (key->ecdsa == NULL) {
return -1;
}
g = EC_KEY_get0_group(key->ecdsa);
p = EC_POINT_new(g);
if (p == NULL) {
return -1;
}
ok = EC_POINT_oct2point(g,
p,
ssh_string_data(e),
ssh_string_len(e),
NULL);
if (!ok) {
EC_POINT_free(p);
return -1;
}
/* EC_KEY_set_public_key duplicates p */
ok = EC_KEY_set_public_key(key->ecdsa, p);
EC_POINT_free(p);
if (!ok) {
return -1;
}
return 0;
}
/* TODO : split this function in two so it becomes smaller */
SIGNATURE *signature_from_string(ssh_session session, ssh_string signature,
ssh_public_key pubkey, int needed_type) {
SIGNATURE *sign = NULL;
ssh_buffer tmpbuf = NULL;
ssh_string rs = NULL;
ssh_string type_s = NULL;
ssh_string e = NULL;
char *type_c = NULL;
int type;
int len;
int rsalen;
#ifdef HAVE_LIBGCRYPT
gcry_sexp_t sig;
#elif defined HAVE_LIBCRYPTO
DSA_SIG *sig = NULL;
ssh_string r = NULL;
ssh_string s = NULL;
#endif
sign = malloc(sizeof(SIGNATURE));
if (sign == NULL) {
ssh_set_error(session, SSH_FATAL, "Not enough space");
return NULL;
}
ZERO_STRUCTP(sign);
tmpbuf = ssh_buffer_new();
if (tmpbuf == NULL) {
ssh_set_error(session, SSH_FATAL, "Not enough space");
signature_free(sign);
return NULL;
}
if (buffer_add_data(tmpbuf, ssh_string_data(signature), ssh_string_len(signature)) < 0) {
signature_free(sign);
ssh_buffer_free(tmpbuf);
return NULL;
}
type_s = buffer_get_ssh_string(tmpbuf);
if (type_s == NULL) {
ssh_set_error(session, SSH_FATAL, "Invalid signature packet");
signature_free(sign);
ssh_buffer_free(tmpbuf);
return NULL;
}
type_c = ssh_string_to_char(type_s);
ssh_string_free(type_s);
if (type_c == NULL) {
signature_free(sign);
ssh_buffer_free(tmpbuf);
return NULL;
}
type = ssh_type_from_name(type_c);
SAFE_FREE(type_c);
if (needed_type != type) {
ssh_set_error(session, SSH_FATAL, "Invalid signature type: %s",
ssh_type_to_char(type));
signature_free(sign);
ssh_buffer_free(tmpbuf);
return NULL;
}
switch(needed_type) {
case SSH_KEYTYPE_DSS:
rs = buffer_get_ssh_string(tmpbuf);
ssh_buffer_free(tmpbuf);
/* 40 is the dual signature blob len. */
if (rs == NULL || ssh_string_len(rs) != 40) {
ssh_string_free(rs);
signature_free(sign);
return NULL;
}
/* we make use of strings (because we have all-made functions to convert
* them to bignums (ou pas ;) */
#ifdef HAVE_LIBGCRYPT
if (gcry_sexp_build(&sig, NULL, "(sig-val(dsa(r %b)(s %b)))",
20 ,ssh_string_data(rs), 20,(unsigned char *)ssh_string_data(rs) + 20)) {
ssh_string_free(rs);
signature_free(sign);
return NULL;
}
#elif defined HAVE_LIBCRYPTO
r = ssh_string_new(20);
s = ssh_string_new(20);
if (r == NULL || s == NULL) {
ssh_string_free(r);
ssh_string_free(s);
ssh_string_free(rs);
signature_free(sign);
return NULL;
}
ssh_string_fill(r, ssh_string_data(rs), 20);
ssh_string_fill(s, (char *)ssh_string_data(rs) + 20, 20);
sig = DSA_SIG_new();
if (sig == NULL) {
ssh_string_free(r);
ssh_string_free(s);
ssh_string_free(rs);
signature_free(sign);
return NULL;
}
sig->r = make_string_bn(r); /* is that really portable ? Openssh's hack isn't better */
sig->s = make_string_bn(s);
ssh_string_free(r);
ssh_string_free(s);
if (sig->r == NULL || sig->s == NULL) {
ssh_string_free(rs);
DSA_SIG_free(sig);
signature_free(sign);
return NULL;
}
#endif
#ifdef DEBUG_CRYPTO
ssh_print_hexa("r", ssh_string_data(rs), 20);
ssh_print_hexa("s", (const unsigned char *)ssh_string_data(rs) + 20, 20);
#endif
ssh_string_free(rs);
sign->type = SSH_KEYTYPE_DSS;
sign->dsa_sign = sig;
return sign;
case SSH_KEYTYPE_RSA:
e = buffer_get_ssh_string(tmpbuf);
ssh_buffer_free(tmpbuf);
if (e == NULL) {
signature_free(sign);
return NULL;
}
len = ssh_string_len(e);
#ifdef HAVE_LIBGCRYPT
rsalen = (gcry_pk_get_nbits(pubkey->rsa_pub) + 7) / 8;
#elif defined HAVE_LIBCRYPTO
rsalen = RSA_size(pubkey->rsa_pub);
#endif
if (len > rsalen) {
ssh_string_free(e);
signature_free(sign);
ssh_set_error(session, SSH_FATAL, "Signature too big! %d instead of %d",
len, rsalen);
return NULL;
}
if (len < rsalen) {
ssh_log(session, SSH_LOG_RARE, "RSA signature len %d < %d",
len, rsalen);
}
sign->type = SSH_KEYTYPE_RSA;
#ifdef HAVE_LIBGCRYPT
if (gcry_sexp_build(&sig, NULL, "(sig-val(rsa(s %b)))",
ssh_string_len(e), ssh_string_data(e))) {
signature_free(sign);
ssh_string_free(e);
return NULL;
}
sign->rsa_sign = sig;
#elif defined HAVE_LIBCRYPTO
sign->rsa_sign = e;
#endif
#ifdef DEBUG_CRYPTO
ssh_log(session, SSH_LOG_FUNCTIONS, "len e: %d", len);
ssh_print_hexa("RSA signature", ssh_string_data(e), len);
#endif
#ifdef HAVE_LIBGCRYPT
ssh_string_free(e);
#endif
return sign;
default:
return NULL;
}
return NULL;
}
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) {
ssh_buffer_free(buffer);
return NULL;
}
ZERO_STRUCTP(key);
key->type = SSH_KEYTYPE_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);
ssh_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)))",
ssh_string_len(p), ssh_string_data(p),
ssh_string_len(q), ssh_string_data(q),
ssh_string_len(g), ssh_string_data(g),
ssh_string_len(pubkey), ssh_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", ssh_string_data(p), ssh_string_len(p));
ssh_print_hexa("q", ssh_string_data(q), ssh_string_len(q));
ssh_print_hexa("g", ssh_string_data(g), ssh_string_len(g));
#endif
ssh_string_burn(p);
ssh_string_free(p);
ssh_string_burn(q);
ssh_string_free(q);
ssh_string_burn(g);
ssh_string_free(g);
ssh_string_burn(pubkey);
ssh_string_free(pubkey);
return key;
error:
ssh_string_burn(p);
ssh_string_free(p);
ssh_string_burn(q);
ssh_string_free(q);
ssh_string_burn(g);
ssh_string_free(g);
ssh_string_burn(pubkey);
ssh_string_free(pubkey);
publickey_free(key);
return NULL;
}
/* Signature decoding functions */
ssh_string signature_to_string(SIGNATURE *sign) {
unsigned char buffer[40] = {0};
ssh_buffer tmpbuf = NULL;
ssh_string str = NULL;
ssh_string tmp = NULL;
ssh_string rs = NULL;
int rc = -1;
#ifdef HAVE_LIBGCRYPT
const char *r = NULL;
const char *s = NULL;
gcry_sexp_t sexp;
size_t size = 0;
#elif defined HAVE_LIBCRYPTO
ssh_string r = NULL;
ssh_string s = NULL;
#endif
tmpbuf = ssh_buffer_new();
if (tmpbuf == NULL) {
return NULL;
}
tmp = ssh_string_from_char(ssh_type_to_char(sign->type));
if (tmp == NULL) {
ssh_buffer_free(tmpbuf);
return NULL;
}
if (buffer_add_ssh_string(tmpbuf, tmp) < 0) {
ssh_buffer_free(tmpbuf);
ssh_string_free(tmp);
return NULL;
}
ssh_string_free(tmp);
switch(sign->type) {
case SSH_KEYTYPE_DSS:
#ifdef HAVE_LIBGCRYPT
sexp = gcry_sexp_find_token(sign->dsa_sign, "r", 0);
if (sexp == NULL) {
ssh_buffer_free(tmpbuf);
return NULL;
}
r = gcry_sexp_nth_data(sexp, 1, &size);
if (*r == 0) { /* libgcrypt put 0 when first bit is set */
size--;
r++;
}
memcpy(buffer, r + size - 20, 20);
gcry_sexp_release(sexp);
sexp = gcry_sexp_find_token(sign->dsa_sign, "s", 0);
if (sexp == NULL) {
ssh_buffer_free(tmpbuf);
return NULL;
}
s = gcry_sexp_nth_data(sexp,1,&size);
if (*s == 0) {
size--;
s++;
}
memcpy(buffer+ 20, s + size - 20, 20);
gcry_sexp_release(sexp);
#elif defined HAVE_LIBCRYPTO
r = make_bignum_string(sign->dsa_sign->r);
if (r == NULL) {
ssh_buffer_free(tmpbuf);
return NULL;
}
s = make_bignum_string(sign->dsa_sign->s);
if (s == NULL) {
ssh_buffer_free(tmpbuf);
ssh_string_free(r);
return NULL;
}
memcpy(buffer, (char *)ssh_string_data(r) + ssh_string_len(r) - 20, 20);
memcpy(buffer + 20, (char *)ssh_string_data(s) + ssh_string_len(s) - 20, 20);
ssh_string_free(r);
ssh_string_free(s);
#endif /* HAVE_LIBCRYPTO */
rs = ssh_string_new(40);
if (rs == NULL) {
ssh_buffer_free(tmpbuf);
return NULL;
}
ssh_string_fill(rs, buffer, 40);
rc = buffer_add_ssh_string(tmpbuf, rs);
ssh_string_free(rs);
if (rc < 0) {
ssh_buffer_free(tmpbuf);
return NULL;
}
break;
case SSH_KEYTYPE_RSA:
case SSH_KEYTYPE_RSA1:
#ifdef HAVE_LIBGCRYPT
sexp = gcry_sexp_find_token(sign->rsa_sign, "s", 0);
if (sexp == NULL) {
ssh_buffer_free(tmpbuf);
return NULL;
}
s = gcry_sexp_nth_data(sexp,1,&size);
if (*s == 0) {
size--;
s++;
}
rs = ssh_string_new(size);
if (rs == NULL) {
ssh_buffer_free(tmpbuf);
return NULL;
}
ssh_string_fill(rs, (char *) s, size);
rc = buffer_add_ssh_string(tmpbuf, rs);
gcry_sexp_release(sexp);
ssh_string_free(rs);
if (rc < 0) {
ssh_buffer_free(tmpbuf);
return NULL;
}
#elif defined HAVE_LIBCRYPTO
if (buffer_add_ssh_string(tmpbuf,sign->rsa_sign) < 0) {
ssh_buffer_free(tmpbuf);
return NULL;
}
#endif
break;
}
str = ssh_string_new(buffer_get_rest_len(tmpbuf));
if (str == NULL) {
ssh_buffer_free(tmpbuf);
return NULL;
}
ssh_string_fill(str, buffer_get_rest(tmpbuf), buffer_get_rest_len(tmpbuf));
ssh_buffer_free(tmpbuf);
return str;
}
/**
* @brief Make a public_key object out of a private_key object.
*
* @param[in] prv The private key to generate the public key.
*
* @returns The generated public key, NULL on error.
*
* @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;
}
ZERO_STRUCTP(key);
key->type = prv->type;
switch(key->type) {
case SSH_KEYTYPE_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 = ssh_string_new(size);
if (p == NULL) {
goto error;
}
ssh_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 = ssh_string_new(size);
if (q == NULL) {
goto error;
}
ssh_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 = ssh_string_new(size);
if (g == NULL) {
goto error;
}
ssh_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 = ssh_string_new(size);
if (y == NULL) {
goto error;
}
ssh_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)))",
ssh_string_len(p), ssh_string_data(p),
ssh_string_len(q), ssh_string_data(q),
ssh_string_len(g), ssh_string_data(g),
ssh_string_len(y), ssh_string_data(y));
ssh_string_burn(p);
ssh_string_free(p);
ssh_string_burn(q);
ssh_string_free(q);
ssh_string_burn(g);
ssh_string_free(g);
ssh_string_burn(y);
ssh_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 SSH_KEYTYPE_RSA:
case SSH_KEYTYPE_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 = ssh_string_new(size);
if (n == NULL) {
goto error;
}
ssh_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 = ssh_string_new(size);
if (e == NULL) {
goto error;
}
ssh_string_fill(e, (char *) tmp, size);
gcry_sexp_release(sexp);
gcry_sexp_build(&key->rsa_pub, NULL,
"(public-key(rsa(n %b)(e %b)))",
ssh_string_len(n), ssh_string_data(n),
ssh_string_len(e), ssh_string_data(e));
if (key->rsa_pub == NULL) {
goto error;
}
ssh_string_burn(e);
ssh_string_free(e);
ssh_string_burn(n);
ssh_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;
default:
publickey_free(key);
return NULL;
}
key->type_c = ssh_type_to_char(prv->type);
return key;
error:
#ifdef HAVE_LIBGCRYPT
gcry_sexp_release(sexp);
ssh_string_burn(p);
ssh_string_free(p);
ssh_string_burn(q);
ssh_string_free(q);
ssh_string_burn(g);
ssh_string_free(g);
ssh_string_burn(y);
ssh_string_free(y);
ssh_string_burn(e);
ssh_string_free(e);
ssh_string_burn(n);
ssh_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) {
ssh_buffer_free(buffer);
return NULL;
}
ZERO_STRUCTP(key);
key->type = type;
key->type_c = ssh_type_to_char(key->type);
e = buffer_get_ssh_string(buffer);
n = buffer_get_ssh_string(buffer);
ssh_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)))",
ssh_string_len(n), ssh_string_data(n),
ssh_string_len(e),ssh_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", ssh_string_data(e), ssh_string_len(e));
ssh_print_hexa("n", ssh_string_data(n), ssh_string_len(n));
#endif
ssh_string_burn(e);
ssh_string_free(e);
ssh_string_burn(n);
ssh_string_free(n);
return key;
error:
ssh_string_burn(e);
ssh_string_free(e);
ssh_string_burn(n);
ssh_string_free(n);
publickey_free(key);
return NULL;
}
ssh_string ssh_encrypt_rsa1(ssh_session session, ssh_string data, ssh_public_key key) {
ssh_string str = NULL;
size_t len = ssh_string_len(data);
size_t size = 0;
#ifdef HAVE_LIBGCRYPT
const char *tmp = NULL;
gcry_sexp_t ret_sexp;
gcry_sexp_t data_sexp;
if (gcry_sexp_build(&data_sexp, NULL, "(data(flags pkcs1)(value %b))",
len, ssh_string_data(data))) {
ssh_set_error(session, SSH_FATAL, "RSA1 encrypt: libgcrypt error");
return NULL;
}
if (gcry_pk_encrypt(&ret_sexp, data_sexp, key->rsa_pub)) {
gcry_sexp_release(data_sexp);
ssh_set_error(session, SSH_FATAL, "RSA1 encrypt: libgcrypt error");
return NULL;
}
gcry_sexp_release(data_sexp);
data_sexp = gcry_sexp_find_token(ret_sexp, "a", 0);
if (data_sexp == NULL) {
ssh_set_error(session, SSH_FATAL, "RSA1 encrypt: libgcrypt error");
gcry_sexp_release(ret_sexp);
return NULL;
}
tmp = gcry_sexp_nth_data(data_sexp, 1, &size);
if (*tmp == 0) {
size--;
tmp++;
}
str = ssh_string_new(size);
if (str == NULL) {
ssh_set_error(session, SSH_FATAL, "Not enough space");
gcry_sexp_release(data_sexp);
gcry_sexp_release(ret_sexp);
return NULL;
}
ssh_string_fill(str, tmp, size);
gcry_sexp_release(data_sexp);
gcry_sexp_release(ret_sexp);
#elif defined HAVE_LIBCRYPTO
size = RSA_size(key->rsa_pub);
str = ssh_string_new(size);
if (str == NULL) {
ssh_set_error(session, SSH_FATAL, "Not enough space");
return NULL;
}
if (RSA_public_encrypt(len, ssh_string_data(data), ssh_string_data(str), key->rsa_pub,
RSA_PKCS1_PADDING) < 0) {
ssh_string_free(str);
return NULL;
}
#endif
return str;
}