// DH鍵を生成する
void dh_gen_key(PTInstVar pvar, DH *dh, int we_need /* bytes */ )
{
int i;
dh->priv_key = NULL;
// 秘密にすべき乱数(X)を生成
for (i = 0 ; i < 10 ; i++) { // retry counter
if (dh->priv_key != NULL) {
BN_clear_free(dh->priv_key);
}
dh->priv_key = BN_new();
if (dh->priv_key == NULL)
goto error;
if (BN_rand(dh->priv_key, 2*(we_need*8), 0, 0) == 0)
goto error;
if (DH_generate_key(dh) == 0)
goto error;
if (dh_pub_is_valid(dh, dh->pub_key))
break;
}
if (i >= 10) {
goto error;
}
return;
error:;
notify_fatal_error(pvar, "error occurred @ dh_gen_key()", TRUE);
}
/* This function does two things:
-- reads data from the sshd and feeds the SSH protocol packets to ssh.c
-- copies any available decrypted session data into the application buffer
*/
int PKT_recv(PTInstVar pvar, char FAR * buf, int buflen)
{
int amount_in_buf = 0;
BOOL connection_closed = FALSE;
while (SSH_is_any_payload(pvar) ? buflen > 0 : !connection_closed) {
if (SSH_is_any_payload(pvar)) {
/* ssh.c has some session data for us to give to Tera Term. */
int grabbed = SSH_extract_payload(pvar, buf, buflen);
amount_in_buf += grabbed;
buf += grabbed;
buflen -= grabbed;
} else if (!pvar->pkt_state.seen_server_ID &&
(pvar->pkt_state.seen_newline
|| pvar->pkt_state.datalen >= 255)) {
/* We're looking for the initial ID string and either we've seen the
terminating newline, or we've exceeded the limit at which we should see
a newline. */
unsigned int i;
for (i = 0;
pvar->pkt_state.buf[i] != '\n'
&& i < pvar->pkt_state.datalen; i++) {
}
if (pvar->pkt_state.buf[i] == '\n') {
i++;
}
// SSHサーバのバージョンチェックを行う
if (SSH_handle_server_ID(pvar, pvar->pkt_state.buf, i)) {
pvar->pkt_state.seen_server_ID = 1;
if (SSHv1(pvar)) {
} else { // for SSH2(yutaka)
// send Key Exchange Init
SSH2_send_kexinit(pvar);
}
} else {
// reset flag to re-read server ID (2008.1.24 yutaka)
pvar->pkt_state.seen_newline = 0;
}
pvar->pkt_state.datastart += i;
pvar->pkt_state.datalen -= i;
} else if (pvar->pkt_state.seen_server_ID
&& pvar->pkt_state.datalen >=
(unsigned int) SSH_get_min_packet_size(pvar)) {
char FAR *data =
pvar->pkt_state.buf + pvar->pkt_state.datastart;
uint32 padding;
uint32 pktsize;
uint32 total_packet_size;
//debug_print(10, data, pvar->pkt_state.datalen);
// SSH2なら暗号化パケットの一部を復号化する。
if (!pvar->pkt_state.predecrypted_packet) {
//DEBUG_PRINT_TO_FILE(0, data, pvar->pkt_state.datalen);
SSH_predecrpyt_packet(pvar, data);
if (SSHv1(pvar)) {
pvar->pkt_state.predecrypted_packet = TRUE;
} else { // for SSH2(yutaka)
// do nothing
pvar->pkt_state.predecrypted_packet = TRUE;
}
}
if (SSHv1(pvar)) {
uint32 realpktsize = get_uint32_MSBfirst(data);
padding = 8 - (realpktsize % 8);
pktsize = realpktsize + padding;
} else {
// SSH2のパケットは先頭に packet-size(4)+padding(1)+type(1) が続く。
pktsize = get_uint32_MSBfirst(data);
padding = (unsigned char) data[4];
}
// パケット(TCPペイロード)の全体のサイズは、SSHペイロード＋4（＋MAC）となる。
// +4は、SSHペイロードのサイズを格納している部分（int型）。
total_packet_size = pktsize + 4 + SSH_get_clear_MAC_size(pvar);
if (total_packet_size <= pvar->pkt_state.datalen) {
/* the data must be 4 byte aligned. */
SSH_handle_packet(pvar, data, pktsize, padding);
pvar->pkt_state.predecrypted_packet = FALSE;
pvar->pkt_state.datastart += total_packet_size;
pvar->pkt_state.datalen -= total_packet_size;
} else if (total_packet_size > PACKET_MAX_SIZE) {
// 4MBを超える巨大なパケットが届いたら、異常終了する。
// 実際にはデータ化けで復号失敗時に、誤認識することが多い。
UTIL_get_lang_msg("MSG_PKT_OVERSIZED_ERROR", pvar,
"Oversized packet received from server; connection will close.");
notify_fatal_error(pvar, pvar->ts->UIMsg, TRUE);
} else {
int amount_read =
recv_data(pvar, max(total_packet_size, READAMOUNT));
if (amount_read == SOCKET_ERROR) {
if (amount_in_buf == 0) {
return SOCKET_ERROR;
} else {
return amount_in_buf;
}
} else {
if (amount_read == 0) {
connection_closed = TRUE;
}
}
}
} else {
// パケットの受信（最大60KB）
int amount_read;
if (pvar->pkt_state.seen_server_ID == 0) {
//amount_read = recv_line_data(pvar);
amount_read = recv_data(pvar, READAMOUNT);
} else {
amount_read = recv_data(pvar, READAMOUNT);
}
if (amount_read == SOCKET_ERROR) {
if (amount_in_buf == 0) {
return SOCKET_ERROR;
} else {
return amount_in_buf;
}
} else if (amount_read == 0) {
connection_closed = TRUE;
}
}
if (pvar->fatal_error) {
return amount_in_buf;
}
}
if (SSH_is_any_payload(pvar)) {
PostMessage(pvar->NotificationWindow, WM_USER_COMMNOTIFY,
pvar->socket, MAKELPARAM(FD_READ, 0));
}
return amount_in_buf;
}
