New subject: [U-Boot-Users] multicast tftp: RFC2090

8 Jun 2007

HiDave,
On Fri, 2007-05-18 at 12:05 -0500, David Updegraff wrote:
...
Ok; here my mulicast TFTP patch.  Have had the opportunity to test with
both the RTL8139 and TSEC ethernet drivers, with up to a dozen clients
concurrent.
In a way I'm tempted to simply remove the #if CONFIG_RFC7090 clutter as
it is benign if you happen to be talking to a non-multicast tftp server;
and would make things rather more readable.  But too timid...
-dbu.
I apologize for taking so long to get to this.  I like it and will work
hard to get it included ASAP.  However, there are a few nits:
...

diff --git a/README b/README
index bb5b46e..29a308d 100644
--- a/README
+++ b/README
@@ -1112,6 +1112,16 @@ The following options need to be configured:
                Defines a default value for theIP address of a TFTP
                server to contact when using the "tftboot" command.
+- Multicast TFTP Mode:

          CONFIG_RFC7090



          Defines whether you want to support multicast TFTP as



per

          rfc-7090; for example to work with atftp.  Lets lots of



targets

          tftp down the same boot image concurrently.  Note: the



ethernet

          driver in use must provide a function: mcast() to



join/leave a

          multicast group.



          CONFIG_BOOTP_RANDOM_DELAY




BOOTP Recovery Mode:
             CONFIG_BOOTP_RANDOM_DELAY

I'd rather see it called CONFIG_MCAST_TFTP (or something like that) and
reference the RFC in the README.  You're right that the CONFIG is
probably not needed anyway, but if it's in plain English it doesn't
really hurt and will save a few bytes for those not using it.
<snip>
...
#endif /* CFG_CMD_NET && CONFIG_NET_MULTI && CONFIG_RTL8139 */
diff --git a/drivers/tsec.c b/drivers/tsec.c
index b418773..66d01dd 100644
--- a/drivers/tsec.c
+++ b/drivers/tsec.c
@@ -129,6 +129,9 @@ static int tsec_miiphy_write(char *devname, unsigned
char addr,
                             unsigned char reg, unsigned short value);
 static int tsec_miiphy_read(char *devname, unsigned char addr,
                            unsigned char reg, unsigned short *value);
+#ifdef CONFIG_RFC2090  /* Multicast TFTP ? */
+static int tsec_bcast_addr (struct eth_device *dev, u8 bcast_mac, u8
set);
+#endif
/* Initialize device structure. Returns success if PHY

initialization succeeded (i.e. if it recognizes the PHY)

@@ -167,6 +170,9 @@ int tsec_initialize(bd_t * bis, int index, char
*devname)
        dev->halt = tsec_halt;
        dev->send = tsec_send;
        dev->recv = tsec_recv;
+#ifdef CONFIG_RFC2090  /* Multicast TFTP ? */

  dev->mcast = tsec_bcast_addr;



+#endif
    /* Tell u-boot to get the addr from the env */
    for (i = 0; i < 6; i++)

@@ -1479,4 +1485,46 @@ static int tsec_miiphy_write(char *devname,
unsigned char addr,
 #endif /* defined(CONFIG_MII) || (CONFIG_COMMANDS & CFG_CMD_MII)
                && !defined(BITBANGMII) */
+#ifdef CONFIG_RFC2090  /* Multicast TFTP ? */



+/* CREDITS: linux gianfar driver, slightly adjusted... thanx. */



+/* Set the appropriate hash bit for the given addr */



+/* The algorithm works like so:



Take the Destination Address (ie the multicast address), and





do a CRC on it (little endian), and reverse the bits of the



result.




Use the 8 most significant bits as a hash into a 256-entry





table.  The table is controlled through 8 32-bit registers:



gaddr0-7.  gaddr0's MSB is entry 0, and gaddr7's LSB is



gaddr7.  This means that the 3 most significant bits in the



hash index which gaddr register to use, and the 5 other bits



indicate which bit (assuming an IBM numbering scheme, which



for PowerPC (tm) is usually the case) in the tregister holds



the entry. */



+static int
+tsec_bcast_addr (struct eth_device *dev, u8 bcast_mac, u8 set)
+{
Why don't you call this function 'tsec_mcast_addr'?  Enabling the
reception of broadcast frames on this device is done by flipping a bit
in the RCTRL register.
<snip>
...
@@ -102,7 +102,9 @@ struct eth_device {
        int  (*send) (struct eth_device*, volatile void* pachet, int
I know this isn't yours, but while in here, can you fix this typo
please?  It looks kinda French, but I think it should then be 'paquet'.
<snip>
...
+#ifdef CONFIG_RFC2090
+int eth_mcast_join( IPaddr_t mcast_addr, u8 join);
+u32 ether_crc (size_t len, unsigned char const *p);
+#endif



/**********************************************************************/
 /*
diff --git a/net/eth.c b/net/eth.c
index 0fc2211..22243eb 100644
--- a/net/eth.c
+++ b/net/eth.c
@@ -369,6 +369,51 @@ void eth_set_enetaddr(int num, char *addr) {
    memcpy(dev->enetaddr, enetaddr, 6);

}
+#ifdef CONFIG_RFC2090
+/* Multicast.


mcast_addr: multicast ipaddr from which multicast Mac is made



join: 1=join, 0=leave.


*/

+int eth_mcast_join( IPaddr_t mcast_ip, u8 join)
+{

u8 mcast_mac[6];
  if (!eth_current || !eth_current->mcast) 


          return -1;


  mcast_mac[5] = htonl(mcast_ip) & 0xff;


  mcast_mac[4] = (htonl(mcast_ip)>>8) & 0xff;


  mcast_mac[3] = (htonl(mcast_ip)>>16) & 0x7f;


  mcast_mac[2] = 0x5e;


  mcast_mac[1] = 0x0;


  mcast_mac[0] = 0x1;


  return eth_current->mcast(eth_current, mcast_mac, join);



+}



+/* the 'way' for ethernet-CRC-32. Spliced in from Linux lib/crc32.c


and this is the ethernet-crc method needed for TSEC -- and perhaps



some
Line's a bit long...
...


other adapter -- hash tables


*/

+#define CRCPOLY_LE 0xedb88320
+u32 ether_crc (size_t len, unsigned char const *p)
+{

  int i;


  u32 crc;


  crc = ~0;


  while (len--) {


          crc ^= *p++;


          for (i = 0; i < 8; i++)


                  crc = (crc >> 1) ^ ((crc & 1) ? CRCPOLY_LE : 0);


  }


  /* an reverse the bits, cuz of way they arrive -- last-first */


  crc = (crc >> 16) | (crc << 16);


  crc = (crc >> 8 & 0x00ff00ff) | (crc << 8 & 0xff00ff00);


  crc = (crc >> 4 & 0x0f0f0f0f) | (crc << 4 & 0xf0f0f0f0);


  crc = (crc >> 2 & 0x33333333) | (crc << 2 & 0xcccccccc);


  crc = (crc >> 1 & 0x55555555) | (crc << 1 & 0xaaaaaaaa);


  return crc;



+}



If this is indeed different from the CRC-32 algorithms that we already
have (yeah, I got curious and wrote a little test program and got
different results, then laziness kicked in and I didn't go any further),
then it would be nice to put it in lib_generic or something like that.
For now, though, this is fine.
<snip>
...
diff --git a/net/tftp.c b/net/tftp.c
index f3a5471..21ccadb 100644
--- a/net/tftp.c
+++ b/net/tftp.c
@@ -61,6 +61,31 @@ static char *tftp_filename;
 extern flash_info_t flash_info[];
 #endif
+#ifdef CONFIG_RFC2090  /* Multicast TFTP */
+#include <malloc.h>
I guess you had a good reason for playing the malloc/free game instead
of a static allocation?
...
+/* 8k bit map .. 8k blocks is 16M.. max?? */
+#define MTFTP_BITMAPSIZE       0x2000
+static unsigned *Bitmap;
+static int PrevBitmapHole ;
+static uchar ProhibitMcast=0;
+static uchar MasterClient=0;
+static uchar Multicast=0;
+static void parse_multicast_oack(char *pkt,int len);
+extern IPaddr_t Mcast_addr;
+static int Mcast_port;
+static ulong TftpEndingBlock; /* .. I can get 'last' block before
done..*/



+static void
+mcast_cleanup(void)
+{

  if (Mcast_addr) eth_mcast_join(Mcast_addr, 0);


  if (Bitmap) free(Bitmap);


  Bitmap=NULL;


  Mcast_addr = Multicast = Mcast_port = 0;


  TftpEndingBlock = -1;



+}
+#endif /* RFC2090 */



static __inline__ void
 store_block (unsigned block, uchar * src, unsigned len)
 {
@@ -90,6 +115,10 @@ store_block (unsigned block, uchar * src, unsigned
len)
        {
                (void)memcpy((void *)(load_addr + offset), src, len);
        }
+#ifdef CONFIG_RFC2090

  if (Multicast)


          ext2_set_bit(block, Bitmap);



+#endif
    if (NetBootFileXferSize < newsize)
            NetBootFileXferSize = newsize;

@@ -108,6 +137,11 @@ TftpSend (void)
        int                     len = 0;
        volatile ushort *s;
+#ifdef CONFIG_RFC2090

  /* Multicast TFTP.. non-MasterClients do not ACK data. */


  if (Multicast && (TftpState == STATE_DATA) && (MasterClient ==



0))
Line's a bit long here too.
...

          return;



+#endif
        /*
         *      We will always be sending some sort of packet, so
         *      cobble together the packet headers now.
@@ -132,11 +166,24 @@ TftpSend (void)
                printf("send option "timeout %s"\n", (char *)pkt);
 #endif
                pkt += strlen((char *)pkt) + 1;
+#ifdef CONFIG_RFC2090

          if (!ProhibitMcast && eth_get_dev()->mcast) {


                  pkt += sprintf((char *)pkt,"multicast");


                  *pkt++ = '\0';


                  *pkt++ = '\0';


          }



+#endif /* RFC2090 */
                len = pkt - xp;
                break;

  case STATE_DATA:
  case STATE_OACK:



+#ifdef CONFIG_RFC2090

          /* ..the next one that I want.. */


          if (Multicast)


                  TftpBlock =



ext2_find_next_zero_bit(Bitmap,(MTFTP_BITMAPSIZE*8),0);

          /*..falling..*/



+#endif

  case STATE_DATA:
          xp = pkt;
          s = (ushort *)pkt;
          *s++ = htons(TFTP_ACK);



@@ -179,6 +226,9 @@ TftpHandler (uchar * pkt, unsigned dest, unsigned
src, unsigned len)
        ushort *s;
    if (dest != TftpOurPort) {

+#ifdef CONFIG_RFC2090

          if (!Mcast_port || (dest != Mcast_port)) 



+#endif
                return;
        }
        if (TftpState != STATE_RRQ && src != TftpServerPort) {
@@ -208,6 +258,12 @@ TftpHandler (uchar * pkt, unsigned dest, unsigned
src, unsigned len)
 #endif
                TftpState = STATE_OACK;
                TftpServerPort = src;
+#ifdef CONFIG_RFC2090

          parse_multicast_oack((char *)pkt,len-1);


          if ((Multicast) && (!MasterClient)) 


                  TftpState = STATE_DATA; /* non-master just



listens */
Oh no, another long line.
...

          else



+#endif
                TftpSend (); /* Send ACK */
                break;
        case TFTP_DATA:
@@ -248,6 +304,11 @@ TftpHandler (uchar * pkt, unsigned dest, unsigned
src, unsigned len)
                        TftpBlockWrap = 0;
                        TftpBlockWrapOffset = 0;
+#ifdef CONFIG_RFC2090

                  if (Multicast) { /* ..happens commonly if mcast



*/

                          TftpLastBlock = TftpBlock - 1;


                  } else



+#endif
                        if (TftpBlock != 1) {   /* Assertion */
                                printf ("\nTFTP error: "
                                        "First block is not block 1 (%
ld)\n"
@@ -274,8 +335,33 @@ TftpHandler (uchar * pkt, unsigned dest, unsigned
src, unsigned len)
                 *      Acknoledge the block just received, which will
prompt
                 *      the server for the next one.
                 */
+#ifdef CONFIG_RFC2090

          /* if I am the MasterClient, actively calculate what my



next needed

           * block is; else I'm passive; not ACKING 


           */


          if (Multicast) {


                  if (len < TFTP_BLOCK_SIZE)  {


                          TftpEndingBlock = TftpBlock;


                  } else if (MasterClient) {


                          TftpBlock = PrevBitmapHole = 


                                          ext2_find_next_zero_bit(


                                                  Bitmap,(MTFTP_BITMAPSIZE*8),PrevBitmapHole);



Far too long.  These 8-character tabs can be a pain...  I'll stop
commenting about line length here.  Please make sure all lines are <
(U-boot max line length), which I believe is 78.
...

                          TftpLastBlock = TftpBlock;


                  }


          }



+#endif
                TftpSend ();
+#ifdef CONFIG_RFC2090

          if (Multicast) {


                  if (MasterClient && (TftpBlock >=



TftpEndingBlock)) {

                          puts ("\nMulticast tftp done\n");


                          mcast_cleanup();


                          NetState = NETLOOP_SUCCESS;


                  } 


          }


          else



+#endif
                if (len < TFTP_BLOCK_SIZE) {
                        /*
                         *      We received the whole thing.  Try to
@@ -290,6 +376,9 @@ TftpHandler (uchar * pkt, unsigned dest, unsigned
src, unsigned len)
                printf ("\nTFTP error: '%s' (%d)\n",
                                        pkt + 2, ntohs(*(ushort *)pkt));
                puts ("Starting again\n\n");
+#ifdef CONFIG_RFC2090

          mcast_cleanup();



+#endif
                NetStartAgain ();
                break;
        }
@@ -301,6 +390,9 @@ TftpTimeout (void)
 {
        if (++TftpTimeoutCount > TIMEOUT_COUNT) {
                puts ("\nRetry count exceeded; starting again\n");
+#ifdef CONFIG_RFC2090

          mcast_cleanup();



+#endif
                NetStartAgain ();
        } else {+               memset (Bitmap,0,MTFTP_BITMAPSIZE);

          PrevBitmapHole = 0;


          Multicast = 1;


  }


  addr = string_to_ip(mc_adr);


  if (Mcast_addr != addr) {


          if (Mcast_addr)


                  eth_mcast_join(Mcast_addr, 0);


          if (eth_mcast_join(Mcast_addr=addr, 1)) {


                  printf ("Fail to set bcast, revert to vanilla



TFTP\n");

                  ProhibitMcast = 1;


                  mcast_cleanup();


                  NetStartAgain ();


                  return;


          }


  }


  MasterClient = (unsigned char)simple_strtoul((char *)mc,&e,10);


  Mcast_port = (unsigned short)simple_strtoul(port,&e,10);


  printf ("Multicast: %s:%d [%d]\n", mc_adr, Mcast_port,



MasterClient);

  return;



+}




+#endif /* Multicast TFTP */



#endif /* CFG_CMD_NET */
            puts ("T ");+               memset (Bitmap,0,MTFTP_BITMAPSIZE);


          PrevBitmapHole = 0;


          Multicast = 1;


  }


  addr = string_to_ip(mc_adr);


  if (Mcast_addr != addr) {


          if (Mcast_addr)


                  eth_mcast_join(Mcast_addr, 0);


          if (eth_mcast_join(Mcast_addr=addr, 1)) {


                  printf ("Fail to set bcast, revert to vanilla



TFTP\n");

                  ProhibitMcast = 1;


                  mcast_cleanup();


                  NetStartAgain ();


                  return;


          }


  }


  MasterClient = (unsigned char)simple_strtoul((char *)mc,&e,10);


  Mcast_port = (unsigned short)simple_strtoul(port,&e,10);


  printf ("Multicast: %s:%d [%d]\n", mc_adr, Mcast_port,



MasterClient);

  return;



+}




+#endif /* Multicast TFTP */



#endif /* CFG_CMD_NET */
@@ -370,6 +462,7 @@ TftpStart (void)
        TftpState = STATE_RRQ;
        /* Use a pseudo-random port unless a specific port is set */
        TftpOurPort = 1024 + (get_timer(0) % 3072);



#ifdef CONFIG_TFTP_PORT
        if ((ep = getenv("tftpdstp")) != NULL) {
                TftpServerPort = simple_strtol(ep, NULL, 10);
@@ -382,8 +475,97 @@ TftpStart (void)
    /* zero out server ether in case the server ip has changed */
    memset(NetServerEther, 0, 6);

+#ifdef CONFIG_RFC2090  /* Multicast TFTP */

mcast_cleanup();

+#endif
    TftpSend ();

}
+#ifdef CONFIG_RFC2090  /* Multicast TFTP */
+/* Credits: atftp project.

*/


+/* pick up BcastAddr, Port, and whether I am [now] the master-client. *


Frame:



+-------+-----------+---+-------~~-------+---+



|  opc  | multicast | 0 | addr, port, mc | 0 |



+-------+-----------+---+-------~~-------+---+



The multicast addr/port becomes what I listen to, and if 'mc' is '1'



then


I am the new master-client so must send ACKs to DataBlocks.  If I am



not


master-client, I'm a passive client, gathering what DataBlocks I may



and


making note of which ones I got in my bitmask.



In theory, I never go from master->passive..



.. this comes in with pkt already pointing just past opc


*/

+static void parse_multicast_oack(char *pkt, int len)
+{

int i;
IPaddr_t addr;
char *mc_adr, *port, *mc, *e;

  mc_adr=port=mc=NULL;


  /* march along looking for 'multicast\0', which has to start at



least

   * 14 bytes back from the end.


   */


  for (i=0;i<len-14;i++)


          if (strcmp (pkt+i,"multicast") == 0)


                  break;


  if (i >= (len-14)) {


          printf ("non-Multicast OACK, ign.\n");


          return;


  }


  i+=10; /* strlen multicast */


  mc_adr = pkt+i;


  for (;i<len;i++) {


          if (*(pkt+i) == ',') {


                  *(pkt+i) = '\0';


                  if (port) {


                          mc=pkt+i+1;


                          break;


                  } else {


                          port = pkt+i+1;


                  }


          }


  }


  if (!port || !mc_adr || !mc ) return;


  if (Multicast && MasterClient) {


          printf ("I got a OACK as master Client, WRONG!\n");


          return;


  }


  /* ..I now accept packets destined for this MCAST addr, port */


  if (!Multicast) {


          if (Bitmap) { 


                  printf ("BUGBUGBUG Dave! why is this set!\n");


                  free(Bitmap);


          }



Cute, but what if this happens and the user isn't named Dave?
...

          if (!(Bitmap = malloc (MTFTP_BITMAPSIZE))) {


                  printf ("OH NO! No Bitmap!\n");


                  return;


          }



Same comment, but minus the Dave part.
All in all, nice work.  Nicely commented too.
regards,
Ben

    

Re: [U-Boot-Users] multicast tftp: RFC2090

Ben Warren

Wolfgang Denk

David Updegraff

Ben Warren

Wolfgang Denk

Ben Warren

David Updegraff

David Updegraff

Wolfgang Denk

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