adb.c

/*
 * "Adb" backend.
 */

#include <stdio.h>
#include <stdlib.h>

#include "putty.h"

#ifndef FALSE
#define FALSE 0
#endif
#ifndef TRUE
#define TRUE 1
#endif

#define ADB_MAX_BACKLOG 4096

typedef struct adb_backend_data {
    const struct plug_function_table *fn;
    /* the above field _must_ be first in the structure */

    Socket s;
    int bufsize;
    void *frontend;
	int state;
} *Adb;

static void adb_size(void *handle, int width, int height);

static void c_write(Adb adb, char *buf, int len)
{
    int backlog = from_backend(adb->frontend, 0, buf, len);
    sk_set_frozen(adb->s, backlog > ADB_MAX_BACKLOG);
}

static void adb_log(Plug plug, int type, SockAddr addr, int port,
		    const char *error_msg, int error_code)
{
    Adb adb = (Adb) plug;
    char addrbuf[256], *msg;

    sk_getaddr(addr, addrbuf, lenof(addrbuf));

    if (type == 0)
	msg = dupprintf("Connecting to %s port %d", addrbuf, port);
    else
	msg = dupprintf("Failed to connect to %s: %s", addrbuf, error_msg);

    logevent(adb->frontend, msg);
}

static int adb_closing(Plug plug, const char *error_msg, int error_code,
		       int calling_back)
{
    Adb adb = (Adb) plug;

    if (adb->s) {
        sk_close(adb->s);
        adb->s = NULL;
	notify_remote_exit(adb->frontend);
    }
    if (error_msg) {
	/* A socket error has occurred. */
	logevent(adb->frontend, error_msg);
	connection_fatal(adb->frontend, "%s", error_msg);
    }				       /* Otherwise, the remote side closed the connection normally. */
    return 0;
}

static int adb_receive(Plug plug, int urgent, char *data, int len)
{
    Adb adb = (Adb) plug;
	if (adb->state==1) {
		if (data[0]=='O') { // OKAY
			sk_write(adb->s,"0006shell:",10);
			adb->state=2; // wait for shell start response
		} else {
			if (data[0]=='F') {
				char* d = (char*)smalloc(len+1);
				memcpy(d,data,len);
				d[len]='\0';
				connection_fatal(adb->frontend, "adb failure message: '%s'", d+8);
				sfree(d);
			} else {
				connection_fatal(adb->frontend, "Bad response");
			}
			return 0;
		}
	} else if (adb->state==2) {
		if (data[0]=='O') { //OKAY
			adb->state=3; // shell started, switch to terminal mode
		} else {
			if (data[0]=='F') {
				char* d = (char*)smalloc(len+1);
				memcpy(d,data,len);
				d[len]='\0';
				connection_fatal(adb->frontend, "%s", d+8);
				sfree(d);
			} else {
				connection_fatal(adb->frontend, "Bad response");
			}
			return 0;
		}
	} else {
		c_write(adb, data, len);
	}
    return 1;
}

static void adb_sent(Plug plug, int bufsize)
{
    Adb adb = (Adb) plug;
    adb->bufsize = bufsize;
}

/*
 * Called to set up the adb connection.
 * 
 * Returns an error message, or NULL on success.
 *
 * Also places the canonical host name into `realhost'. It must be
 * freed by the caller.
 */
static const char *adb_init(void *frontend_handle, void **backend_handle,
			    Config *cfg,
			    char *host, int port, char **realhost, int nodelay,
			    int keepalive)
{
    static const struct plug_function_table fn_table = {
	adb_log,
	adb_closing,
	adb_receive,
	adb_sent
    };
    SockAddr addr;
    const char *err;
    Adb adb;
	char sendhost[512];

    adb = snew(struct adb_backend_data);
    adb->fn = &fn_table;
    adb->s = NULL;
	adb->state = 0;
    *backend_handle = adb;

    adb->frontend = frontend_handle;

    /*
     * Try to find host.
     */
    {
	char *buf;
	buf = dupprintf("Looking up host \"%s\"%s", "localhost",
			(cfg->addressfamily == ADDRTYPE_IPV4 ? " (IPv4)" :
			 (cfg->addressfamily == ADDRTYPE_IPV6 ? " (IPv6)" :
			  "")));
	logevent(adb->frontend, buf);
	sfree(buf);
    }
    addr = name_lookup("localhost", port, realhost, cfg, cfg->addressfamily);
    if ((err = sk_addr_error(addr)) != NULL) {
	sk_addr_free(addr);
	return err;
    }

    if (port < 0)
	port = 5037;		       /* default adb port */

    /*
     * Open socket.
     */
    adb->s = new_connection(addr, *realhost, port, 0, 1, nodelay, keepalive,
			    (Plug) adb, cfg);
    if ((err = sk_socket_error(adb->s)) != NULL)
	return err;

    if (*cfg->loghost) {
	char *colon;

	sfree(*realhost);
	*realhost = dupstr(cfg->loghost);
	colon = strrchr(*realhost, ':');
	if (colon) {
	    /*
	     * FIXME: if we ever update this aspect of ssh.c for
	     * IPv6 literal management, this should change in line
	     * with it.
	     */
	    *colon++ = '\0';
	}
    }

    /* send initial data to adb server */
#define ADB_SHELL_DEFAULT_STR "0012" "host:transport-usb"
#define ADB_SHELL_DEFAULT_STR_LEN (sizeof(ADB_SHELL_DEFAULT_STR)-1)
#define ADB_SHELL_SERIAL_PREFIX "host:transport:"
#define ADB_SHELL_SERIAL_PREFIX_LEN (sizeof(ADB_SHELL_SERIAL_PREFIX)-1)
    do {
	size_t len = strlen(host);
	if (len == 0) {
	    sk_write(adb->s, ADB_SHELL_DEFAULT_STR, ADB_SHELL_DEFAULT_STR_LEN);
	    sk_flush(adb->s);
	    adb->state = 1;
	} else {
	    char sendbuf[512];
#define ADB_SHELL_HOST_MAX_LEN (sizeof(sendbuf)-4-ADB_SHELL_SERIAL_PREFIX_LEN)
	    if (len > ADB_SHELL_HOST_MAX_LEN)
		len = ADB_SHELL_HOST_MAX_LEN;
	    sprintf(sendbuf,"%04x" ADB_SHELL_SERIAL_PREFIX, len+ADB_SHELL_SERIAL_PREFIX_LEN);
	    memcpy(sendbuf+4+ADB_SHELL_SERIAL_PREFIX_LEN, host, len);
	    sk_write(adb->s,sendbuf,len+4+ADB_SHELL_SERIAL_PREFIX_LEN);
	    sk_flush(adb->s);
	    adb->state = 1;
	}
    } while (0);
    return NULL;
}

static void adb_free(void *handle)
{
    Adb adb = (Adb) handle;

    if (adb->s)
	sk_close(adb->s);
    sfree(adb);
}

/*
 * Stub routine (we don't have any need to reconfigure this backend).
 */
static void adb_reconfig(void *handle, Config *cfg)
{
}

/*
 * Called to send data down the adb connection.
 */
static int adb_send(void *handle, char *buf, int len)
{
    Adb adb = (Adb) handle;

    if (adb->s == NULL)
	return 0;

    adb->bufsize = sk_write(adb->s, buf, len);

    return adb->bufsize;
}

/*
 * Called to query the current socket sendability status.
 */
static int adb_sendbuffer(void *handle)
{
    Adb adb = (Adb) handle;
    return adb->bufsize;
}

/*
 * Called to set the size of the window
 */
static void adb_size(void *handle, int width, int height)
{
    /* Do nothing! */
    return;
}

/*
 * Send adb special codes.
 */
static void adb_special(void *handle, Telnet_Special code)
{
    /* Do nothing! */
    return;
}

/*
 * Return a list of the special codes that make sense in this
 * protocol.
 */
static const struct telnet_special *adb_get_specials(void *handle)
{
    return NULL;
}

static int adb_connected(void *handle)
{
    Adb adb = (Adb) handle;
    return adb->s != NULL;
}

static int adb_sendok(void *handle)
{
    return 1;
}

static void adb_unthrottle(void *handle, int backlog)
{
    Adb adb = (Adb) handle;
    sk_set_frozen(adb->s, backlog > ADB_MAX_BACKLOG);
}

static int adb_ldisc(void *handle, int option)
{
    // Don't allow line discipline options
    return 0;
}

static void adb_provide_ldisc(void *handle, void *ldisc)
{
    /* This is a stub. */
}

static void adb_provide_logctx(void *handle, void *logctx)
{
    /* This is a stub. */
}

static int adb_exitcode(void *handle)
{
    Adb adb = (Adb) handle;
    if (adb->s != NULL)
        return -1;                     /* still connected */
    else
        /* Exit codes are a meaningless concept in the Adb protocol */
        return 0;
}

/*
 * cfg_info for Adb does nothing at all.
 */
static int adb_cfg_info(void *handle)
{
    return 0;
}

Backend adb_backend = {
    adb_init,
    adb_free,
    adb_reconfig,
    adb_send,
    adb_sendbuffer,
    adb_size,
    adb_special,
    adb_get_specials,
    adb_connected,
    adb_exitcode,
    adb_sendok,
    adb_ldisc,
    adb_provide_ldisc,
    adb_provide_logctx,
    adb_unthrottle,
    adb_cfg_info,
    "adb",
    PROT_ADB,
    5037
};