int sftp_reply_names(sftp_client_message msg) {
ssh_buffer out;
out = ssh_buffer_new();
if (out == NULL) {
ssh_buffer_free(msg->attrbuf);
return -1;
}
if (ssh_buffer_add_u32(out, msg->id) < 0 ||
ssh_buffer_add_u32(out, htonl(msg->attr_num)) < 0 ||
ssh_buffer_add_data(out, ssh_buffer_get(msg->attrbuf),
ssh_buffer_get_len(msg->attrbuf)) < 0 ||
sftp_packet_write(msg->sftp, SSH_FXP_NAME, out) < 0) {
ssh_buffer_free(out);
ssh_buffer_free(msg->attrbuf);
return -1;
}
ssh_buffer_free(out);
ssh_buffer_free(msg->attrbuf);
msg->attr_num = 0;
msg->attrbuf = NULL;
return 0;
}
int sftp_reply_status(sftp_client_message msg, uint32_t status,
const char *message) {
ssh_buffer out;
ssh_string s;
out = ssh_buffer_new();
if (out == NULL) {
return -1;
}
s = ssh_string_from_char(message ? message : "");
if (s == NULL) {
ssh_buffer_free(out);
return -1;
}
if (ssh_buffer_add_u32(out, msg->id) < 0 ||
ssh_buffer_add_u32(out, htonl(status)) < 0 ||
ssh_buffer_add_ssh_string(out, s) < 0 ||
ssh_buffer_add_u32(out, 0) < 0 || /* language string */
sftp_packet_write(msg->sftp, SSH_FXP_STATUS, out) < 0) {
ssh_buffer_free(out);
ssh_string_free(s);
return -1;
}
ssh_buffer_free(out);
ssh_string_free(s);
return 0;
}
int sftp_reply_name(sftp_client_message msg, const char *name,
sftp_attributes attr) {
ssh_buffer out;
ssh_string file;
out = ssh_buffer_new();
if (out == NULL) {
return -1;
}
file = ssh_string_from_char(name);
if (file == NULL) {
ssh_buffer_free(out);
return -1;
}
if (ssh_buffer_add_u32(out, msg->id) < 0 ||
ssh_buffer_add_u32(out, htonl(1)) < 0 ||
ssh_buffer_add_ssh_string(out, file) < 0 ||
ssh_buffer_add_ssh_string(out, file) < 0 || /* The protocol is broken here between 3 & 4 */
buffer_add_attributes(out, attr) < 0 ||
sftp_packet_write(msg->sftp, SSH_FXP_NAME, out) < 0) {
ssh_buffer_free(out);
ssh_string_free(file);
return -1;
}
ssh_buffer_free(out);
ssh_string_free(file);
return 0;
}
int sftp_reply_data(sftp_client_message msg, const void *data, int len) {
ssh_buffer out;
out = ssh_buffer_new();
if (out == NULL) {
return -1;
}
if (ssh_buffer_add_u32(out, msg->id) < 0 ||
ssh_buffer_add_u32(out, ntohl(len)) < 0 ||
ssh_buffer_add_data(out, data, len) < 0 ||
sftp_packet_write(msg->sftp, SSH_FXP_DATA, out) < 0) {
ssh_buffer_free(out);
return -1;
}
ssh_buffer_free(out);
return 0;
}
int sftp_reply_attr(sftp_client_message msg, sftp_attributes attr) {
ssh_buffer out;
out = ssh_buffer_new();
if (out == NULL) {
return -1;
}
if (ssh_buffer_add_u32(out, msg->id) < 0 ||
buffer_add_attributes(out, attr) < 0 ||
sftp_packet_write(msg->sftp, SSH_FXP_ATTRS, out) < 0) {
ssh_buffer_free(out);
return -1;
}
ssh_buffer_free(out);
return 0;
}
int sftp_reply_handle(sftp_client_message msg, ssh_string handle){
ssh_buffer out;
out = ssh_buffer_new();
if (out == NULL) {
return -1;
}
if (ssh_buffer_add_u32(out, msg->id) < 0 ||
ssh_buffer_add_ssh_string(out, handle) < 0 ||
sftp_packet_write(msg->sftp, SSH_FXP_HANDLE, out) < 0) {
ssh_buffer_free(out);
return -1;
}
ssh_buffer_free(out);
return 0;
}
/*
* Test the behavior of ssh_buffer_get_ssh_string with invalid data
*/
static void *thread_ssh_buffer_get_ssh_string(void *threadid)
{
ssh_buffer buffer = NULL;
size_t i, j, k, l;
int rc;
/* some values that can go wrong */
uint32_t values[] = {
0xffffffff, 0xfffffffe, 0xfffffffc, 0xffffff00,
0x80000000, 0x80000004, 0x7fffffff};
char data[128] = {0};
/* Unused */
(void)threadid;
memset(data, 'X', sizeof(data));
for (i = 0; i < ARRAY_SIZE(values); ++i) {
for (j = 0; j < (int)sizeof(data); ++j) {
for (k = 1; k < 5; ++k) {
buffer = ssh_buffer_new();
assert_non_null(buffer);
for (l = 0; l < k; ++l) {
rc = ssh_buffer_add_u32(buffer, htonl(values[i]));
assert_int_equal(rc, 0);
}
rc = ssh_buffer_add_data(buffer,data,j);
assert_int_equal(rc, 0);
for (l = 0; l < k; ++l) {
ssh_string str = ssh_buffer_get_ssh_string(buffer);
assert_null(str);
SSH_STRING_FREE(str);
}
SSH_BUFFER_FREE(buffer);
}
}
}
pthread_exit(NULL);
}
int ssh_packet_send1(ssh_session session) {
unsigned int blocksize = (session->current_crypto ?
session->current_crypto->out_cipher->blocksize : 8);
uint32_t currentlen = ssh_buffer_get_len(session->out_buffer) + sizeof(uint32_t);
char padstring[32] = {0};
int rc = SSH_ERROR;
uint32_t finallen;
uint32_t crc;
uint8_t padding;
SSH_LOG(SSH_LOG_PACKET,"Sending a %d bytes long packet",currentlen);
/* TODO FIXME
#ifdef WITH_ZLIB
if (session->current_crypto && session->current_crypto->do_compress_out) {
if (compress_buffer(session, session->out_buffer) < 0) {
goto error;
}
currentlen = ssh_buffer_get_len(session->out_buffer);
}
#endif
*/
padding = blocksize - (currentlen % blocksize);
if (session->current_crypto) {
ssh_get_random(padstring, padding, 0);
} else {
memset(padstring, 0, padding);
}
finallen = htonl(currentlen);
SSH_LOG(SSH_LOG_PACKET,
"%d bytes after comp + %d padding bytes = %d bytes packet",
currentlen, padding, ntohl(finallen));
if (ssh_buffer_prepend_data(session->out_buffer, &padstring, padding) < 0) {
goto error;
}
if (ssh_buffer_prepend_data(session->out_buffer, &finallen, sizeof(uint32_t)) < 0) {
goto error;
}
crc = ssh_crc32((char *)ssh_buffer_get(session->out_buffer) + sizeof(uint32_t),
ssh_buffer_get_len(session->out_buffer) - sizeof(uint32_t));
if (ssh_buffer_add_u32(session->out_buffer, ntohl(crc)) < 0) {
goto error;
}
#ifdef DEBUG_CRYPTO
ssh_print_hexa("Clear packet", ssh_buffer_get(session->out_buffer),
ssh_buffer_get_len(session->out_buffer));
#endif
/* session->out_buffer should have more than sizeof(uint32_t) bytes
in it as required for ssh_packet_encrypt */
ssh_packet_encrypt(session, (unsigned char *)ssh_buffer_get(session->out_buffer) + sizeof(uint32_t),
ssh_buffer_get_len(session->out_buffer) - sizeof(uint32_t));
#ifdef DEBUG_CRYPTO
ssh_print_hexa("encrypted packet",ssh_buffer_get(session->out_buffer),
ssh_buffer_get_len(session->out_buffer));
#endif
rc=ssh_socket_write(session->socket, ssh_buffer_get(session->out_buffer),
ssh_buffer_get_len(session->out_buffer));
if(rc== SSH_ERROR) {
goto error;
}
session->send_seq++;
if (ssh_buffer_reinit(session->out_buffer) < 0) {
rc = SSH_ERROR;
}
error:
return rc; /* SSH_OK, AGAIN or ERROR */
}
int ssh_make_sessionid(ssh_session session)
{
ssh_string num = NULL;
ssh_buffer server_hash = NULL;
ssh_buffer client_hash = NULL;
ssh_buffer buf = NULL;
ssh_string server_pubkey_blob = NULL;
const_bignum client_pubkey, server_pubkey;
#ifdef WITH_GEX
const_bignum modulus, generator;
#endif
int rc = SSH_ERROR;
buf = ssh_buffer_new();
if (buf == NULL) {
return rc;
}
rc = ssh_buffer_pack(buf,
"ss",
session->clientbanner,
session->serverbanner);
if (rc == SSH_ERROR) {
goto error;
}
if (session->client) {
server_hash = session->in_hashbuf;
client_hash = session->out_hashbuf;
} else {
server_hash = session->out_hashbuf;
client_hash = session->in_hashbuf;
}
/*
* Handle the two final fields for the KEXINIT message (RFC 4253 7.1):
*
* boolean first_kex_packet_follows
* uint32 0 (reserved for future extension)
*/
rc = ssh_buffer_add_u8(server_hash, 0);
if (rc < 0) {
goto error;
}
rc = ssh_buffer_add_u32(server_hash, 0);
if (rc < 0) {
goto error;
}
/* These fields are handled for the server case in ssh_packet_kexinit. */
if (session->client) {
rc = ssh_buffer_add_u8(client_hash, 0);
if (rc < 0) {
goto error;
}
rc = ssh_buffer_add_u32(client_hash, 0);
if (rc < 0) {
goto error;
}
}
rc = ssh_dh_get_next_server_publickey_blob(session, &server_pubkey_blob);
if (rc != SSH_OK) {
goto error;
}
rc = ssh_buffer_pack(buf,
"dPdPS",
ssh_buffer_get_len(client_hash),
ssh_buffer_get_len(client_hash),
ssh_buffer_get(client_hash),
ssh_buffer_get_len(server_hash),
ssh_buffer_get_len(server_hash),
ssh_buffer_get(server_hash),
server_pubkey_blob);
ssh_string_free(server_pubkey_blob);
if(rc != SSH_OK){
goto error;
}
switch(session->next_crypto->kex_type) {
case SSH_KEX_DH_GROUP1_SHA1:
case SSH_KEX_DH_GROUP14_SHA1:
case SSH_KEX_DH_GROUP16_SHA512:
case SSH_KEX_DH_GROUP18_SHA512:
rc = ssh_dh_keypair_get_keys(session->next_crypto->dh_ctx,
DH_CLIENT_KEYPAIR, NULL, &client_pubkey);
if (rc != SSH_OK) {
goto error;
}
rc = ssh_dh_keypair_get_keys(session->next_crypto->dh_ctx,
DH_SERVER_KEYPAIR, NULL, &server_pubkey);
if (rc != SSH_OK) {
goto error;
}
rc = ssh_buffer_pack(buf,
"BB",
client_pubkey,
server_pubkey);
if (rc != SSH_OK) {
goto error;
}
break;
#ifdef WITH_GEX
case SSH_KEX_DH_GEX_SHA1:
case SSH_KEX_DH_GEX_SHA256:
rc = ssh_dh_keypair_get_keys(session->next_crypto->dh_ctx,
DH_CLIENT_KEYPAIR, NULL, &client_pubkey);
if (rc != SSH_OK) {
goto error;
}
rc = ssh_dh_keypair_get_keys(session->next_crypto->dh_ctx,
DH_SERVER_KEYPAIR, NULL, &server_pubkey);
if (rc != SSH_OK) {
goto error;
}
rc = ssh_dh_get_parameters(session->next_crypto->dh_ctx,
&modulus, &generator);
if (rc != SSH_OK) {
goto error;
}
rc = ssh_buffer_pack(buf,
"dddBBBB",
session->next_crypto->dh_pmin,
session->next_crypto->dh_pn,
session->next_crypto->dh_pmax,
modulus,
generator,
client_pubkey,
server_pubkey);
if (rc != SSH_OK) {
goto error;
}
break;
#endif /* WITH_GEX */
#ifdef HAVE_ECDH
case SSH_KEX_ECDH_SHA2_NISTP256:
case SSH_KEX_ECDH_SHA2_NISTP384:
case SSH_KEX_ECDH_SHA2_NISTP521:
if (session->next_crypto->ecdh_client_pubkey == NULL ||
session->next_crypto->ecdh_server_pubkey == NULL) {
SSH_LOG(SSH_LOG_WARNING, "ECDH parameted missing");
goto error;
}
rc = ssh_buffer_pack(buf,
"SS",
session->next_crypto->ecdh_client_pubkey,
session->next_crypto->ecdh_server_pubkey);
if (rc != SSH_OK) {
goto error;
}
break;
#endif
#ifdef HAVE_CURVE25519
case SSH_KEX_CURVE25519_SHA256:
case SSH_KEX_CURVE25519_SHA256_LIBSSH_ORG:
rc = ssh_buffer_pack(buf,
"dPdP",
CURVE25519_PUBKEY_SIZE,
(size_t)CURVE25519_PUBKEY_SIZE, session->next_crypto->curve25519_client_pubkey,
CURVE25519_PUBKEY_SIZE,
(size_t)CURVE25519_PUBKEY_SIZE, session->next_crypto->curve25519_server_pubkey);
if (rc != SSH_OK) {
goto error;
}
break;
#endif
}
rc = ssh_buffer_pack(buf, "B", session->next_crypto->shared_secret);
if (rc != SSH_OK) {
goto error;
}
#ifdef DEBUG_CRYPTO
ssh_print_hexa("hash buffer", ssh_buffer_get(buf), ssh_buffer_get_len(buf));
#endif
switch (session->next_crypto->kex_type) {
case SSH_KEX_DH_GROUP1_SHA1:
case SSH_KEX_DH_GROUP14_SHA1:
#ifdef WITH_GEX
case SSH_KEX_DH_GEX_SHA1:
#endif /* WITH_GEX */
session->next_crypto->digest_len = SHA_DIGEST_LENGTH;
session->next_crypto->digest_type = SSH_KDF_SHA1;
session->next_crypto->secret_hash = malloc(session->next_crypto->digest_len);
if (session->next_crypto->secret_hash == NULL) {
ssh_set_error_oom(session);
goto error;
}
sha1(ssh_buffer_get(buf), ssh_buffer_get_len(buf),
session->next_crypto->secret_hash);
break;
case SSH_KEX_ECDH_SHA2_NISTP256:
case SSH_KEX_CURVE25519_SHA256:
case SSH_KEX_CURVE25519_SHA256_LIBSSH_ORG:
#ifdef WITH_GEX
case SSH_KEX_DH_GEX_SHA256:
#endif /* WITH_GEX */
session->next_crypto->digest_len = SHA256_DIGEST_LENGTH;
session->next_crypto->digest_type = SSH_KDF_SHA256;
session->next_crypto->secret_hash = malloc(session->next_crypto->digest_len);
if (session->next_crypto->secret_hash == NULL) {
ssh_set_error_oom(session);
goto error;
}
sha256(ssh_buffer_get(buf), ssh_buffer_get_len(buf),
session->next_crypto->secret_hash);
break;
case SSH_KEX_ECDH_SHA2_NISTP384:
session->next_crypto->digest_len = SHA384_DIGEST_LENGTH;
session->next_crypto->digest_type = SSH_KDF_SHA384;
session->next_crypto->secret_hash = malloc(session->next_crypto->digest_len);
if (session->next_crypto->secret_hash == NULL) {
ssh_set_error_oom(session);
goto error;
}
sha384(ssh_buffer_get(buf), ssh_buffer_get_len(buf),
session->next_crypto->secret_hash);
break;
case SSH_KEX_DH_GROUP16_SHA512:
case SSH_KEX_DH_GROUP18_SHA512:
case SSH_KEX_ECDH_SHA2_NISTP521:
session->next_crypto->digest_len = SHA512_DIGEST_LENGTH;
session->next_crypto->digest_type = SSH_KDF_SHA512;
session->next_crypto->secret_hash = malloc(session->next_crypto->digest_len);
if (session->next_crypto->secret_hash == NULL) {
ssh_set_error_oom(session);
goto error;
}
sha512(ssh_buffer_get(buf),
ssh_buffer_get_len(buf),
session->next_crypto->secret_hash);
break;
}
/* During the first kex, secret hash and session ID are equal. However, after
* a key re-exchange, a new secret hash is calculated. This hash will not replace
* but complement existing session id.
*/
if (!session->next_crypto->session_id) {
session->next_crypto->session_id = malloc(session->next_crypto->digest_len);
if (session->next_crypto->session_id == NULL) {
ssh_set_error_oom(session);
goto error;
}
memcpy(session->next_crypto->session_id, session->next_crypto->secret_hash,
session->next_crypto->digest_len);
}
#ifdef DEBUG_CRYPTO
printf("Session hash: \n");
ssh_print_hexa("secret hash", session->next_crypto->secret_hash, session->next_crypto->digest_len);
ssh_print_hexa("session id", session->next_crypto->session_id, session->next_crypto->digest_len);
#endif
rc = SSH_OK;
error:
ssh_buffer_free(buf);
ssh_buffer_free(client_hash);
ssh_buffer_free(server_hash);
session->in_hashbuf = NULL;
session->out_hashbuf = NULL;
ssh_string_free(num);
return rc;
}
