[U-Boot-Users] multicast tftp: RFC2090
Ben Warren
bwarren at qstreams.com
Fri Jun 8 17:24:52 CEST 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:
> + * 1) Take the Destination Address (ie the multicast address), and
> + * do a CRC on it (little endian), and reverse the bits of the
> + * result.
> + * 2) 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
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