#define crStopV		do{ *crLine = 0; return; }while(0)
#define crWaitUntil(c)	do { crReturn(0); } while (!(c))
#define crWaitUntilV(c)	do { crReturnV; } while (!(c))

typedef struct ssh_tag *Ssh;
struct Packet;

static struct Packet *ssh1_pkt_init(int pkt_type);
static struct Packet *ssh2_pkt_init(int pkt_type);
static void ssh_pkt_ensure(struct Packet *, int length);
static void ssh_pkt_adddata(struct Packet *, void *data, int len);
static void ssh_pkt_addbyte(struct Packet *, unsigned char value);
static void ssh2_pkt_addbool(struct Packet *, unsigned char value);
static void ssh_pkt_adduint32(struct Packet *, unsigned long value);
static void ssh_pkt_addstring_start(struct Packet *);
static void ssh_pkt_addstring_str(struct Packet *, char *data);
static void ssh_pkt_addstring_data(struct Packet *, char *data, int len);
static void ssh_pkt_addstring(struct Packet *, char *data);
static unsigned char *ssh2_mpint_fmt(Bignum b, int *len);
static void ssh1_pkt_addmp(struct Packet *, Bignum b);
static void ssh2_pkt_addmp(struct Packet *, Bignum b);
static int ssh2_pkt_construct(Ssh, struct Packet *);
static void ssh2_pkt_send(Ssh, struct Packet *);
static void ssh2_pkt_send_noqueue(Ssh, struct Packet *);
static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen,
			 struct Packet *pktin);
static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,

    void *local;
};
#define free_portfwd(pf) ( \
    ((pf) ? (sfree((pf)->saddr), sfree((pf)->daddr), \
	     sfree((pf)->sserv), sfree((pf)->dserv)) : (void)0 ), sfree(pf) )

struct Packet {
    long length;	    /* length of `data' actually used */
    long forcepad;	    /* SSH-2: force padding to at least this length */
    int type;		    /* only used for incoming packets */
    unsigned long sequence; /* SSH-2 incoming sequence number */
    unsigned char *data;    /* allocated storage */
    unsigned char *body;    /* offset of payload within `data' */
    long savedpos;	    /* temporary index into `data' (for strings) */
    long maxlen;	    /* amount of storage allocated for `data' */
    long encrypted_len;	    /* for SSH-2 total-size counting */

    /*
     * State associated with packet logging
     */
    int logmode;
    int nblanks;
    struct logblank_t *blanks;

    sfree(pkt->data);
    sfree(pkt);
}
static struct Packet *ssh_new_packet(void)
{
    struct Packet *pkt = snew(struct Packet);

    pkt->body = pkt->data = NULL;
    pkt->maxlen = 0;
    pkt->logmode = PKTLOG_EMIT;
    pkt->nblanks = 0;
    pkt->blanks = NULL;

    return pkt;
}

		   st->pktin->data+6, st->pktin->length-6,
		   nblanks, &blank);
    }

    crFinish(st->pktin);
}




























static int s_wrpkt_prepare(Ssh ssh, struct Packet *pkt, int *offset_p)
{
    int pad, biglen, i, pktoffs;
    unsigned long crc;
#ifdef __SC__
    /*
     * XXX various versions of SC (including 8.8.4) screw up the
     * register allocation in this function and use the same register
     * (D6) for len and as a temporary, with predictable results.  The
     * following sledgehammer prevents this.
     */
    volatile
#endif
    int len;



    if (ssh->logctx)
	log_packet(ssh->logctx, PKT_OUTGOING, pkt->data[12],
		   ssh1_pkt_type(pkt->data[12]),
		   pkt->body, pkt->length - (pkt->body - pkt->data),
		   pkt->nblanks, pkt->blanks);
    sfree(pkt->blanks); pkt->blanks = NULL;
    pkt->nblanks = 0;

    if (ssh->v1_compressing) {
	unsigned char *compblk;
	int complen;
	zlib_compress_block(ssh->cs_comp_ctx,
			    pkt->data + 12, pkt->length - 12,
			    &compblk, &complen);

	memcpy(pkt->data + 12, compblk, complen);
	sfree(compblk);
	pkt->length = complen + 12;
    }

    ssh_pkt_ensure(pkt, pkt->length + 4); /* space for CRC */
    pkt->length += 4;
    len = pkt->length - 4 - 8;	/* len(type+data+CRC) */
    pad = 8 - (len % 8);
    pktoffs = 8 - pad;
    biglen = len + pad;		/* len(padding+type+data+CRC) */

    for (i = pktoffs; i < 4+8; i++)
	pkt->data[i] = random_byte();
    crc = crc32_compute(pkt->data + pktoffs + 4, biglen - 4); /* all ex len */
    PUT_32BIT(pkt->data + pktoffs + 4 + biglen - 4, crc);
    PUT_32BIT(pkt->data + pktoffs, len);

    if (ssh->cipher)
	ssh->cipher->encrypt(ssh->v1_cipher_ctx,
			     pkt->data + pktoffs + 4, biglen);

    if (offset_p) *offset_p = pktoffs;
    return biglen + 4;		/* len(length+padding+type+data+CRC) */
}

static void s_wrpkt(Ssh ssh, struct Packet *pkt)
{
    int len, backlog, offset;
    len = s_wrpkt_prepare(ssh, pkt, &offset);
    backlog = sk_write(ssh->s, (char *)pkt->data + offset, len);
    if (backlog > SSH_MAX_BACKLOG)
	ssh_throttle_all(ssh, 1, backlog);
    ssh_free_packet(pkt);
}

static void s_wrpkt_defer(Ssh ssh, struct Packet *pkt)
{
    int len, offset;
    len = s_wrpkt_prepare(ssh, pkt, &offset);
    if (ssh->deferred_len + len > ssh->deferred_size) {
	ssh->deferred_size = ssh->deferred_len + len + 128;
	ssh->deferred_send_data = sresize(ssh->deferred_send_data,
					  ssh->deferred_size,
					  unsigned char);
    }
    memcpy(ssh->deferred_send_data + ssh->deferred_len,
	   pkt->data + offset, len);
    ssh->deferred_len += len;
    ssh_free_packet(pkt);
}

/*
 * Construct a SSH-1 packet with the specified contents.
 * (This all-at-once interface used to be the only one, but now SSH-1
 * packets can also be constructed incrementally.)
 */
static struct Packet *construct_packet(Ssh ssh, int pkttype, va_list ap)

{


    int argtype;
    Bignum bn;
    struct Packet *pkt;

    pkt = ssh1_pkt_init(pkttype);

    while ((argtype = va_arg(ap, int)) != PKT_END) {










	unsigned char *argp, argchar;




	unsigned long argint;

	int arglen;




















	switch (argtype) {
	  /* Actual fields in the packet */
	  case PKT_INT:
	    argint = va_arg(ap, int);
	    ssh_pkt_adduint32(pkt, argint);

	    break;
	  case PKT_CHAR:
	    argchar = (unsigned char) va_arg(ap, int);
	    ssh_pkt_addbyte(pkt, argchar);

	    break;
	  case PKT_DATA:
	    argp = va_arg(ap, unsigned char *);
	    arglen = va_arg(ap, int);
	    ssh_pkt_adddata(pkt, argp, arglen);

	    break;
	  case PKT_STR:
	    argp = va_arg(ap, unsigned char *);


	    ssh_pkt_addstring(pkt, argp);

	    break;
	  case PKT_BIGNUM:
	    bn = va_arg(ap, Bignum);
	    ssh1_pkt_addmp(pkt, bn);
	    break;
	  /* Tokens for modifications to packet logging */
	  case PKTT_PASSWORD:
	    dont_log_password(ssh, pkt, PKTLOG_BLANK);
	    break;
	  case PKTT_DATA:
	    dont_log_data(ssh, pkt, PKTLOG_OMIT);
	    break;
	  case PKTT_OTHER:
	    end_log_omission(ssh, pkt);
	    break;
	}










    }

    return pkt;
}

static void send_packet(Ssh ssh, int pkttype, ...)
{
    struct Packet *pkt;
    va_list ap;
    va_start(ap, pkttype);

    pkt = construct_packet(ssh, pkttype, ap);
    va_end(ap);

    s_wrpkt(ssh, pkt);

}

static void defer_packet(Ssh ssh, int pkttype, ...)
{
    struct Packet *pkt;
    va_list ap;
    va_start(ap, pkttype);

    pkt = construct_packet(ssh, pkttype, ap);
    va_end(ap);

    s_wrpkt_defer(ssh, pkt);

}

static int ssh_versioncmp(char *a, char *b)
{
    char *ae, *be;
    unsigned long av, bv;

    return 0;
}

/*
 * Utility routines for putting an SSH-protocol `string' and
 * `uint32' into a SHA state.
 */

static void sha_string(SHA_State * s, void *str, int len)
{
    unsigned char lenblk[4];
    PUT_32BIT(lenblk, len);
    SHA_Bytes(s, lenblk, 4);
    SHA_Bytes(s, str, len);
}

static void sha_uint32(SHA_State * s, unsigned i)
{
    unsigned char intblk[4];
    PUT_32BIT(intblk, i);
    SHA_Bytes(s, intblk, 4);
}

/*
 * Packet construction functions. Mostly shared between SSH-1 and SSH-2.
 */
static void ssh_pkt_ensure(struct Packet *pkt, int length)
{
    if (pkt->maxlen < length) {
	unsigned char *body = pkt->body;
	int offset = body ? pkt->data - body : 0;
	pkt->maxlen = length + 256;
	pkt->data = sresize(pkt->data, pkt->maxlen + APIEXTRA, unsigned char);
	if (body) pkt->body = pkt->data + offset;
    }
}
static void ssh_pkt_adddata(struct Packet *pkt, void *data, int len)
{
    if (pkt->logmode != PKTLOG_EMIT) {
	pkt->nblanks++;
	pkt->blanks = sresize(pkt->blanks, pkt->nblanks, struct logblank_t);
	assert(pkt->body);
	pkt->blanks[pkt->nblanks-1].offset = pkt->length -
					     (pkt->body - pkt->data);
	pkt->blanks[pkt->nblanks-1].len = len;
	pkt->blanks[pkt->nblanks-1].type = pkt->logmode;
    }
    pkt->length += len;
    ssh_pkt_ensure(pkt, pkt->length);
    memcpy(pkt->data + pkt->length - len, data, len);
}
static void ssh_pkt_addbyte(struct Packet *pkt, unsigned char byte)
{
    ssh_pkt_adddata(pkt, &byte, 1);








}
static void ssh2_pkt_addbool(struct Packet *pkt, unsigned char value)
{
    ssh_pkt_adddata(pkt, &value, 1);
}
static void ssh_pkt_adduint32(struct Packet *pkt, unsigned long value)
{
    unsigned char x[4];
    PUT_32BIT(x, value);
    ssh_pkt_adddata(pkt, x, 4);
}
static void ssh_pkt_addstring_start(struct Packet *pkt)
{
    ssh_pkt_adduint32(pkt, 0);
    pkt->savedpos = pkt->length;
}
static void ssh_pkt_addstring_str(struct Packet *pkt, char *data)
{
    ssh_pkt_adddata(pkt, data, strlen(data));
    PUT_32BIT(pkt->data + pkt->savedpos - 4, pkt->length - pkt->savedpos);
}
static void ssh_pkt_addstring_data(struct Packet *pkt, char *data, int len)
{
    ssh_pkt_adddata(pkt, data, len);
    PUT_32BIT(pkt->data + pkt->savedpos - 4, pkt->length - pkt->savedpos);
}
static void ssh_pkt_addstring(struct Packet *pkt, char *data)
{
    ssh_pkt_addstring_start(pkt);
    ssh_pkt_addstring_str(pkt, data);
}
static void ssh1_pkt_addmp(struct Packet *pkt, Bignum b)
{
    int len = ssh1_bignum_length(b);
    unsigned char *data = snewn(len, char);
    (void) ssh1_write_bignum(data, b);
    ssh_pkt_adddata(pkt, data, len);
    sfree(data);
}
static unsigned char *ssh2_mpint_fmt(Bignum b, int *len)
{
    unsigned char *p;
    int i, n = (bignum_bitcount(b) + 7) / 8;
    p = snewn(n + 1, unsigned char);
    if (!p)

    return p;
}
static void ssh2_pkt_addmp(struct Packet *pkt, Bignum b)
{
    unsigned char *p;
    int len;
    p = ssh2_mpint_fmt(b, &len);
    ssh_pkt_addstring_start(pkt);
    ssh_pkt_addstring_data(pkt, (char *)p, len);
    sfree(p);
}

static struct Packet *ssh1_pkt_init(int pkt_type)
{
    struct Packet *pkt = ssh_new_packet();
    pkt->length = 4 + 8;	    /* space for length + max padding */
    ssh_pkt_addbyte(pkt, pkt_type);
    pkt->body = pkt->data + pkt->length;
    return pkt;
}

/* For legacy code (SSH-1 and -2 packet construction used to be separate) */
#define ssh2_pkt_ensure(pkt, length) ssh_pkt_ensure(pkt, length)
#define ssh2_pkt_adddata(pkt, data, len) ssh_pkt_adddata(pkt, data, len)
#define ssh2_pkt_addbyte(pkt, byte) ssh_pkt_addbyte(pkt, byte)
#define ssh2_pkt_adduint32(pkt, value) ssh_pkt_adduint32(pkt, value)
#define ssh2_pkt_addstring_start(pkt) ssh_pkt_addstring_start(pkt)
#define ssh2_pkt_addstring_str(pkt, data) ssh_pkt_addstring_str(pkt, data)
#define ssh2_pkt_addstring_data(pkt, data, len) ssh_pkt_addstring_data(pkt, data, len)
#define ssh2_pkt_addstring(pkt, data) ssh_pkt_addstring(pkt, data)

static struct Packet *ssh2_pkt_init(int pkt_type)
{
    struct Packet *pkt = ssh_new_packet();
    pkt->length = 5;
    pkt->forcepad = 0;
    ssh_pkt_addbyte(pkt, (unsigned char) pkt_type);
    pkt->body = pkt->data + pkt->length;
    return pkt;
}

/*
 * Construct an SSH-2 final-form packet: compress it, encrypt it,
 * put the MAC on it. Final packet, ready to be sent, is stored in
 * pkt->data. Total length is returned.
 */
static int ssh2_pkt_construct(Ssh ssh, struct Packet *pkt)
{
    int cipherblk, maclen, padding, i;

    if (ssh->logctx)
	log_packet(ssh->logctx, PKT_OUTGOING, pkt->data[5],
		   ssh2_pkt_type(ssh->pkt_ctx, pkt->data[5]),
		   pkt->body, pkt->length - (pkt->body - pkt->data),
		   pkt->nblanks, pkt->blanks);
    sfree(pkt->blanks); pkt->blanks = NULL;
    pkt->nblanks = 0;

    /*
     * Compress packet payload.
     */