tftp.c

完整的Bell实验室的嵌入式文件系统TFS

        TftpCount = -1;
        return(-1);
    }
    SendTFTPAck(ehdr,block);
    return(0);
}

/* SendTFTPRRQ():
 *  Pass the ether and ip address of the TFTP server, along with the
 *  filename and mode to start up a target-initiated TFTP download.
 *  The initial TftpState value is TFTPSENTRRQ, this is done so that incoming
 *  TFTP_DAT packets can be verified...
 *   - If a TFTP_DAT packet is received and TftpState is TFTPSENTRRQ, then
 *     the block number should be 1.  If this is true, then that server's
 *     source port is stored away in TftpRmtPort so that all subsequent
 *     TFTP_DAT packets will be compared to the initial source port.  If no
 *     match, then respond with a TFTP error or ICMP PortUnreachable message.
 *   - If a TFTP_DAT packet is received and TftpState is TFTPSENTRRQ, then
 *     if the block number is not 1, generate a error.
 */
int
SendTFTPRRQ(uchar *ipadd,uchar *eadd,char *filename,char *mode,uchar *loc)
{
    uchar *tftpdat;
    ushort ip_len;
    struct ether_header *te;
    struct ip *ti;
    struct Udphdr *tu;

    TftpChopCount = 0;
    tftpGotoState(TFTPSENTRRQ);
    TftpAddr = loc;
    TftpCount = 0;

    /* Retrieve an ethernet buffer from the driver and populate the
     * ethernet level of packet:
     */
    te = (struct ether_header *) getXmitBuffer();
    memcpy((char *)&te->ether_shost,BinEnetAddr,6);
    memcpy((char *)&te->ether_dhost,eadd,6);
    te->ether_type = ecs(ETHERTYPE_IP);

    /* Move to the IP portion of the packet and populate it appropriately: */
    ti = (struct ip *) (te + 1);
    ti->ip_vhl = IP_HDR_VER_LEN;
    ti->ip_tos = 0;
    ip_len = sizeof(struct ip) +
        sizeof(struct Udphdr) + strlen(filename) + strlen(mode) + 4;
    ti->ip_len = ecs(ip_len);
    ti->ip_id = ipId();
    ti->ip_off = 0;
    ti->ip_ttl = UDP_TTL;
    ti->ip_p = IP_UDP;
    memcpy((char *)&ti->ip_src.s_addr,BinIpAddr,4);
    memcpy((char *)&ti->ip_dst.s_addr,ipadd,4);

    /* Now udp... */
    tu = (struct Udphdr *) (ti + 1);
    tu->uh_sport = getTftpSrcPort();
    self_ecs(tu->uh_sport);
    tu->uh_dport = ecs(TftpPort);
    tu->uh_ulen = ecs((ushort)(ip_len - sizeof(struct ip)));

    /* Finally, the TFTP specific stuff... */
    tftpdat = (uchar *)(tu+1);
    *(ushort *)(tftpdat) = ecs(TFTP_RRQ);
    strcpy(tftpdat+2,filename);
    strcpy(tftpdat+2+strlen(filename)+1,mode);

    if (!strcmp(mode,"netascii"))
        TftpWrqMode = MODE_NETASCII;
    else
        TftpWrqMode = MODE_OCTET;

    storePktAndSend(ti, te,TFTPACKSIZE+strlen(filename)+strlen(mode));

    if (EtherVerbose & SHOW_TFTP)
        printf("\n  Sent TFTP_RRQ (file=%s)\n",filename);

    return(0);
}

/* SendTFTPAck():
 */
int
SendTFTPAck(struct ether_header *re,ushort block)
{
    uchar *tftpdat;
    ushort ip_len;
    struct ether_header *te;
    struct ip *ti, *ri;
    struct Udphdr *tu, *ru;

    te = EtherCopy(re);

    ti = (struct ip *) (te + 1);
    ri = (struct ip *) (re + 1);
    ti->ip_vhl = ri->ip_vhl;
    ti->ip_tos = ri->ip_tos;
    ip_len = sizeof(struct ip) + sizeof(struct Udphdr) + 4;
    ti->ip_len = ecs(ip_len);
    ti->ip_id = ipId();
    ti->ip_off = ri->ip_off;
    ti->ip_ttl = UDP_TTL;
    ti->ip_p = IP_UDP;
    memcpy((char *)&(ti->ip_src.s_addr),(char *)&(ri->ip_dst.s_addr),
        sizeof(struct in_addr));
    memcpy((char *)&(ti->ip_dst.s_addr),(char *)&(ri->ip_src.s_addr),
        sizeof(struct in_addr));

    tu = (struct Udphdr *) (ti + 1);
    ru = (struct Udphdr *) (ri + 1);
    tu->uh_sport = ru->uh_dport;
    tu->uh_dport = ru->uh_sport;
    tu->uh_ulen = ecs((ushort)(ip_len - sizeof(struct ip)));

    tftpdat = (uchar *)(tu+1);
    *(ushort *)(tftpdat) = ecs(TFTP_ACK);
    *(ushort *)(tftpdat+2) = ecs(block);

    storePktAndSend(ti,te,TFTPACKSIZE);

    if (EtherVerbose & SHOW_TFTP)
        printf("  Sent TFTP_ACK (blk#%d)\n",block);
    return(0);
}

/* SendTFTPErr():
 */
int
SendTFTPErr(struct ether_header *re,short errno,char *errmsg,int changestate)
{
    short len, tftplen, hdrlen;
    uchar *tftpmsg;
    struct ether_header *te;
    struct ip *ti, *ri;
    struct Udphdr *tu, *ru;

    if (changestate)
        tftpGotoState(TFTPERROR);

    tftplen = strlen(errmsg) + 1 + 4;
    hdrlen = sizeof(struct ip) + sizeof(struct Udphdr);
    len = tftplen + hdrlen ;

    te = EtherCopy(re);

    ti = (struct ip *) (te + 1);
    ri = (struct ip *) (re + 1);
    ti->ip_vhl = ri->ip_vhl;
    ti->ip_tos = ri->ip_tos;
    ti->ip_len = ecs(len);
    ti->ip_id = ipId();
    ti->ip_off = ri->ip_off;
    ti->ip_ttl = UDP_TTL;
    ti->ip_p = IP_UDP;
    memcpy((char *)&(ti->ip_src.s_addr),(char *)&(ri->ip_dst.s_addr),
        sizeof(struct in_addr));
    memcpy((char *)&(ti->ip_dst.s_addr),(char *)&(ri->ip_src.s_addr),
        sizeof(struct in_addr));

    tu = (struct Udphdr *) (ti + 1);
    ru = (struct Udphdr *) (ri + 1);
    tu->uh_sport = ru->uh_dport;
    tu->uh_dport = ru->uh_sport;
    tu->uh_ulen = sizeof(struct Udphdr) + tftplen;
    self_ecs(tu->uh_ulen);

    tftpmsg = (uchar *)(tu+1);
    *(ushort *)(tftpmsg) = ecs(TFTP_ERR);
    * (ushort *)(tftpmsg+2) = ecs(errno);
    strcpy(tftpmsg+4,errmsg);

    storePktAndSend(ti,te,TFTPACKSIZE + strlen(errmsg) + 1);

    if (EtherVerbose & SHOW_TFTP)
        printf("  Sent TFTP Err#%d (%s) \n",errno,errmsg);

    return(0);
}

/* SendTFTPData():
 */
int
SendTFTPData(struct ether_header *re,ushort block,uchar *data,int count)
{
    int len, tftplen, hdrlen;
    uchar *tftpmsg;
    struct ether_header *te;
    struct ip *ti, *ri;
    struct Udphdr *tu, *ru;

    if (count > TFTP_DATAMAX)
        count = TFTP_DATAMAX;

    tftplen = count + 2 + 2; /* sizeof (data + opcode + blockno) */
    hdrlen = sizeof(struct ip) + sizeof(struct Udphdr);
    len = tftplen + hdrlen ;

    te = EtherCopy(re);

    ti = (struct ip *) (te + 1);
    ri = (struct ip *) (re + 1);
    ti->ip_vhl = ri->ip_vhl;
    ti->ip_tos = ri->ip_tos;
    ti->ip_len = ecs(len);
    ti->ip_id = ipId();
    ti->ip_off = ri->ip_off;
    ti->ip_ttl = UDP_TTL;
    ti->ip_p = IP_UDP;
    memcpy((char *)&(ti->ip_src.s_addr),(char *)&(ri->ip_dst.s_addr),
        sizeof(struct in_addr));
    memcpy((char *)&(ti->ip_dst.s_addr),(char *)&(ri->ip_src.s_addr),
        sizeof(struct in_addr));

    tu = (struct Udphdr *) (ti + 1);
    ru = (struct Udphdr *) (ri + 1);
    tu->uh_sport = ru->uh_dport;
    tu->uh_dport = ru->uh_sport;
    tu->uh_ulen = sizeof(struct Udphdr) + tftplen;
    self_ecs(tu->uh_ulen);

    tftpmsg = (uchar *)(tu+1);
    *(ushort *)(tftpmsg) = ecs(TFTP_DAT);
    *(ushort *)(tftpmsg+2) = ecs(block);
    memcpy(tftpmsg+4,data,count);

    len+=sizeof(struct ether_header);

    storePktAndSend(ti,te,len);

    if (EtherVerbose & SHOW_TFTP)
        printf("  Sent TFTP data blk#%d (%d bytes @ 0x%lx) \n",
            block,count,(ulong)data);
    return(0);
}

/* Tftp():
 *  Initiate a tftp transfer at the target (target is client).
 *  Command line:
 *      tftp [options] {IP} {get|put} {file|addr} [len]...
 *      tftp [options] {IP} get file dest_addr
 *      tftp [options] {IP} put addr dest_file len
 *  Currently, only "get" is supported.
 */

char *TftpHelp[] = {
    "Trivial file transfer protocol",
    "-[aF:f:i:nvV] [on|off|IP] {get filename [addr]}",
    " -a        use netascii mode",
    " -F {file} name of tfs file to copy to",
    " -f {flgs} file flags (see tfs)",
    " -i {info} file info (see tfs)",
    " -v        low verbosity",
    " -V        high verbosity",
    0,
};

int
Tftp(int argc,char *argv[])
{
    int     opt;
    char    *mode, *file, *info, *flags;
    ulong   addr;

    file = (char *)0;
    info = (char *)0;
    flags = (char *)0;
    mode = "octet";
    while ((opt=getopt(argc,argv,"aF:f:i:vV")) != -1) {
        switch(opt) {
        case 'a':
            mode = "netascii";
            break;
        case 'f':
            flags = optarg;
            break;
        case 'F':
            file = optarg;
            break;
        case 'i':
            info = optarg;
            break;
        case 'v':
            EtherVerbose |= SHOW_TFTP;
            break;
        case 'V':
            EtherVerbose = SHOW_TFTP | SHOW_INCOMING | SHOW_OUTGOING;
            break;
        default:
            return(CMD_PARAM_ERROR);
        }
    }
    if (argc < (optind+1))
        return(CMD_PARAM_ERROR);

    if (argc == optind+1) {
        if (!strcmp(argv[optind],"on"))
            TftpTurnedOff = 0;
        else if (!strcmp(argv[optind],"off")) {
            TftpTurnedOff = 1;
            tftpGotoState(TFTPIDLE);
        }
        else
            return(CMD_PARAM_ERROR);
        return(CMD_SUCCESS);
    }

    /* If either the info or flags field has been specified, but the */
    /* filename is not specified, error here... */
    if ((info || flags) && (!file)) {
        printf("Filename missing\n");
        return(CMD_FAILURE);
    }

    TftpTurnedOff = 0;
    if (!strcmp(argv[optind+1],"get")) {

        if (argc == optind+4)
            addr = (ulong)strtol(argv[optind+3],0,0);
        else if (argc == optind+3)
            addr = getAppRamStart();
        else
            return(CMD_PARAM_ERROR);

        tftpGet(addr,argv[optind],mode,argv[optind+2],file,flags,info);

        EtherVerbose = 0;
    }
    else if ((argc == optind+5) && !strcmp(argv[optind+1],"put")) {
        printf("tftp 'put' not yet supported\n");
    }
    else
        return(CMD_PARAM_ERROR);

    return(CMD_SUCCESS);
}

void
ShowTftpStats()
{
    printf("Current TFTP state: %s\n",tftpStringState(TftpState));
}

#endif