#define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED     1    /* 0x1 */
#define SSH2_OPEN_CONNECT_FAILED                  2    /* 0x2 */
#define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE            3    /* 0x3 */
#define SSH2_OPEN_RESOURCE_SHORTAGE               4    /* 0x4 */

#define SSH2_EXTENDED_DATA_STDERR                 1    /* 0x1 */

/*
 * Various remote-bug flags.
 */
#define BUG_CHOKES_ON_SSH1_IGNORE                 1
#define BUG_SSH2_HMAC                             2

#define GET_32BIT(cp) \
    (((unsigned long)(unsigned char)(cp)[0] << 24) | \
    ((unsigned long)(unsigned char)(cp)[1] << 16) | \
    ((unsigned long)(unsigned char)(cp)[2] << 8) | \
    ((unsigned long)(unsigned char)(cp)[3]))

#define PUT_32BIT(cp, value) { \

static Socket s = NULL;

static unsigned char session_key[32];
static int ssh1_compressing;
static int ssh_agentfwd_enabled;
static int ssh_X11_fwd_enabled;
static int ssh_remote_bugs;
static const struct ssh_cipher *cipher = NULL;
static const struct ssh2_cipher *cscipher = NULL;
static const struct ssh2_cipher *sccipher = NULL;
static const struct ssh_mac *csmac = NULL;
static const struct ssh_mac *scmac = NULL;
static const struct ssh_compress *cscomp = NULL;
static const struct ssh_compress *sccomp = NULL;

static int s_wrpkt_prepare(void) {
    int pad, len, biglen, i;
    unsigned long crc;

    pktout.body[-1] = pktout.type;

#if 0
    debug(("Packet payload pre-compression:\n"));
    for (i = -1; i < pktout.length; i++)
        debug(("  %02x", (unsigned char)pktout.body[i]));
    debug(("\r\n"));
#endif

    if (ssh1_compressing) {
	unsigned char *compblk;
	int complen;
#if 0
	debug(("Packet payload pre-compression:\n"));
	for (i = -1; i < pktout.length; i++)
	    debug(("  %02x", (unsigned char)pktout.body[i]));
	debug(("\r\n"));
#endif
	zlib_compress_block(pktout.body-1, pktout.length+1,
			    &compblk, &complen);
	ssh1_pktout_size(complen-1);
	memcpy(pktout.body-1, compblk, complen);
	sfree(compblk);
#if 0
	debug(("Packet payload post-compression:\n"));

    if (p[0] & 0x80) {
        bombout(("internal error: Can't handle negative mpints"));
        return NULL;
    }
    b = bignum_from_bytes(p, length);
    return b;
}

/*
 * Examine the remote side's version string and compare it against
 * a list of known buggy implementations.
 */
static void ssh_detect_bugs(char *vstring) {
    char *imp;                         /* pointer to implementation part */
    imp = vstring;
    imp += strcspn(imp, "-");
    imp += strcspn(imp, "-");

    ssh_remote_bugs = 0;

    if (!strcmp(imp, "1.2.18") || !strcmp(imp, "1.2.19") ||
        !strcmp(imp, "1.2.20") || !strcmp(imp, "1.2.21") ||
        !strcmp(imp, "1.2.22")) {
        /*
         * These versions don't support SSH1_MSG_IGNORE, so we have
         * to use a different defence against password length
         * sniffing.
         */
        ssh_remote_bugs |= BUG_CHOKES_ON_SSH1_IGNORE;
        logevent("We believe remote version has SSH1 ignore bug");
    }

    if (!strncmp(imp, "2.1.0", 5) || !strncmp(imp, "2.0.", 4) ||
        !strncmp(imp, "2.2.0", 5) || !strncmp(imp, "2.3.0", 5) ||
        !strncmp(imp, "2.1 ", 4)) {
        /*
         * These versions have the HMAC bug.
         */
        ssh_remote_bugs |= BUG_SSH2_HMAC;
        logevent("We believe remote version has SSH2 HMAC bug");
    }
}

static int do_ssh_init(unsigned char c) {
    static char *vsp;
    static char version[10];
    static char vstring[80];
    static char vlog[sizeof(vstring)+20];
    static int i;

    }

    ssh_agentfwd_enabled = FALSE;
    rdpkt2_state.incoming_sequence = 0;

    *vsp = 0;
    sprintf(vlog, "Server version: %s", vstring);
    ssh_detect_bugs(vstring);
    vlog[strcspn(vlog, "\r\n")] = '\0';
    logevent(vlog);

    /*
     * Server version "1.99" means we can choose whether we use v1
     * or v2 protocol. Choice is based on cfg.sshprot.
     */

                 * 
                 *  - otherwise, we let N be the nearest multiple
                 *    of 8 below the password length, and send 8
                 *    packets containing string lengths N through
                 *    N+7. This won't obscure the order of
                 *    magnitude of the password length, but it will
                 *    introduce a bit of extra uncertainty.
                 * 
                 * A few servers (the old 1.2.18 through 1.2.22)
                 * can't deal with SSH1_MSG_IGNORE. For these
                 * servers, we need an alternative defence. We make
                 * use of the fact that the password is interpreted
                 * as a C string: so we can append a NUL, then some
                 * random data.
                 */
                if (ssh_remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE) {
                int bottom, top, pwlen, i;
                char *randomstr;
                    char string[64];
                    char *s;
                    int len;

                pwlen = strlen(password);
                if (pwlen < 16) {
                    bottom = 1;
                    top = 15;
                    len = strlen(password);
                    if (len < sizeof(string)) {
                        s = string;
                        strcpy(string, password);
                        len++;         /* cover the zero byte */
                        while (len < sizeof(string)) {
                            string[len++] = (char)random_byte();
                        }
                    } else {
                        s = password;
                    }
                    send_packet(pwpkt_type, PKT_INT, len,
                                PKT_DATA, s, len, PKT_END);
                } else {
                    int bottom, top, pwlen, i;
                    char *randomstr;

                    pwlen = strlen(password);
                    if (pwlen < 16) {
                        bottom = 1;
                        top = 15;
                    } else {
                    bottom = pwlen &~ 7;
                    top = bottom + 7;
                }
                        bottom = pwlen &~ 7;
                        top = bottom + 7;
                    }

                assert(pwlen >= bottom && pwlen <= top);
                    assert(pwlen >= bottom && pwlen <= top);

                randomstr = smalloc(top+1);
                    randomstr = smalloc(top+1);

                for (i = bottom; i <= top; i++) {
                    if (i == pwlen)
                        defer_packet(pwpkt_type, PKT_STR, password, PKT_END);
                    else {
                        for (j = 0; j < i; j++) {
                            do {
                                randomstr[j] = random_byte();
                            } while (randomstr[j] == '\0');
                        }
                        randomstr[i] = '\0';
                        defer_packet(SSH1_MSG_IGNORE,
                                     PKT_STR, randomstr, PKT_END);
                    }
                }
                ssh_pkt_defersend();
                    for (i = bottom; i <= top; i++) {
                        if (i == pwlen)
                            defer_packet(pwpkt_type, PKT_STR, password, PKT_END);
                        else {
                            for (j = 0; j < i; j++) {
                                do {
                                    randomstr[j] = random_byte();
                                } while (randomstr[j] == '\0');
                            }
                            randomstr[i] = '\0';
                            defer_packet(SSH1_MSG_IGNORE,
                                         PKT_STR, randomstr, PKT_END);
                        }
                    }
                    ssh_pkt_defersend();
                }
            } else {
                send_packet(pwpkt_type, PKT_STR, password, PKT_END);
            }
        }
	logevent("Sent password");
	memset(password, 0, strlen(password));
	crWaitUntil(ispkt);

	preferred_comp = &ssh_zlib;
    else
	preferred_comp = &ssh_comp_none;

    /*
     * Be prepared to work around the buggy MAC problem.
     */
    if (cfg.buggymac)
    if (cfg.buggymac || (ssh_remote_bugs & BUG_SSH2_HMAC))
        maclist = buggymacs, nmacs = lenof(buggymacs);
    else
        maclist = macs, nmacs = lenof(macs);

    begin_key_exchange:
    /*
     * Construct and send our key exchange packet.