tftp functions moved to proto/tftp.c

src/proto/tftp.c

@@ -0,0 +1,174 @@
+#include "etherboot.h"
+#include "in.h"
+#include "nic.h"
+#include "proto.h"
+#include "tftp.h"
+
+/* Utility function for tftp_block() */
+static int await_tftp ( int ival, void *ptr __unused,
+			unsigned short ptype __unused, struct iphdr *ip,
+			struct udphdr *udp, struct tcphdr *tcp __unused ) {
+	if ( ! udp ) {
+		return 0;
+	}
+	if ( arptable[ARP_CLIENT].ipaddr.s_addr != ip->dest.s_addr )
+		return 0;
+	if ( ntohs ( udp->dest ) != ival )
+		return 0;
+	return 1;
+}
+
+/*
+ * Download a single block via TFTP.  This function is non-static so
+ * that pxe_export.c can call it.
+ *
+ */
+int tftp_block ( struct tftpreq_info_t *request,
+		 struct tftpblk_info_t *block ) {
+	static struct sockaddr_in server;
+	static unsigned short lport = 2000; /* local port */
+	struct tftp_t *rcvd = NULL;
+	static struct tftpreq_t xmit;
+	static unsigned short xmitlen = 0;
+	static unsigned short blockidx = 0; /* Last block received */
+	static unsigned short retry = 0; /* Retry attempts on last block */
+	static int blksize = 0;
+	unsigned short recvlen = 0;
+
+	/* If this is a new request (i.e. if name is set), fill in
+	 * transmit block with RRQ and send it.
+	 */
+	if ( request ) {
+		rx_qdrain(); /* Flush receive queue */
+		xmit.opcode = htons(TFTP_RRQ);
+		xmitlen = (void*)&xmit.u.rrq - (void*)&xmit +
+			sprintf((char*)xmit.u.rrq, "%s%coctet%cblksize%c%d",
+				request->name, 0, 0, 0, request->blksize)
+			+ 1; /* null terminator */
+		blockidx = 0; /* Reset counters */
+		retry = 0;
+		blksize = TFTP_DEFAULTSIZE_PACKET;
+		lport++; /* Use new local port */
+		server = *(request->server);
+		if ( ! server.sin_port )
+			server.sin_port = TFTP_PORT;
+		if ( !udp_transmit(server.sin_addr.s_addr, lport,
+				   server.sin_port, xmitlen, &xmit) )
+			return (0);
+	}
+	/* Exit if no transfer in progress */
+	if ( !blksize ) return (0);
+	/* Loop to wait until we get a packet we're interested in */
+	block->data = NULL; /* Used as flag */
+	while ( block->data == NULL ) {
+		long timeout = rfc2131_sleep_interval ( blockidx ? TFTP_REXMT :
+							TIMEOUT, retry );
+		if ( !await_reply(await_tftp, lport, NULL, timeout) ) {
+			/* No packet received */
+			if ( retry++ > MAX_TFTP_RETRIES ) break;
+			/* Retransmit last packet */
+			if ( !blockidx ) lport++; /* New lport if new RRQ */
+			if ( !udp_transmit(server.sin_addr.s_addr, lport,
+					   server.sin_port, xmitlen, &xmit) )
+				return (0);
+			continue; /* Back to waiting for packet */
+		}
+		/* Packet has been received */
+		rcvd = (struct tftp_t *)&nic.packet[ETH_HLEN];
+		recvlen = ntohs(rcvd->udp.len) - sizeof(struct udphdr)
+			- sizeof(rcvd->opcode);
+		server.sin_port = ntohs(rcvd->udp.src);
+		retry = 0; /* Reset retry counter */
+		switch ( htons(rcvd->opcode) ) {
+		case TFTP_ERROR : {
+			printf ( "TFTP error %d (%s)\n",
+				 ntohs(rcvd->u.err.errcode),
+				 rcvd->u.err.errmsg );
+			return (0); /* abort */
+		}
+		case TFTP_OACK : {
+			const char *p = rcvd->u.oack.data;
+			const char *e = p + recvlen - 10; /* "blksize\0\d\0" */
+
+			*((char*)(p+recvlen-1)) = '\0'; /* Force final 0 */
+			if ( blockidx || !request ) break; /* Too late */
+			if ( recvlen <= TFTP_MAX_PACKET ) /* sanity */ {
+				/* Check for blksize option honoured */
+				while ( p < e ) {
+					if ( strcasecmp("blksize",p) == 0 &&
+					     p[7] == '\0' ) {
+						blksize = strtoul(p+8,&p,10);
+						p++; /* skip null */
+					}
+					while ( *(p++) ) {};
+				}
+			}
+			if ( blksize < TFTP_DEFAULTSIZE_PACKET ||
+			     blksize > request->blksize ) {
+				/* Incorrect blksize - error and abort */
+				xmit.opcode = htons(TFTP_ERROR);
+				xmit.u.err.errcode = 8;
+				xmitlen = (void*)&xmit.u.err.errmsg
+					- (void*)&xmit
+					+ sprintf((char*)xmit.u.err.errmsg,
+						  "RFC1782 error")
+					+ 1;
+				udp_transmit(server.sin_addr.s_addr, lport,
+					     server.sin_port, xmitlen, &xmit);
+				return (0);
+			}
+		} break;
+		case TFTP_DATA :
+			if ( ntohs(rcvd->u.data.block) != ( blockidx + 1 ) )
+				break; /* Re-ACK last block sent */
+			if ( recvlen > ( blksize+sizeof(rcvd->u.data.block) ) )
+				break; /* Too large; ignore */
+			block->data = rcvd->u.data.download;
+			block->block = ++blockidx;
+			block->len = recvlen - sizeof(rcvd->u.data.block);
+			block->eof = ( (unsigned short)block->len < blksize );
+			/* If EOF, zero blksize to indicate transfer done */
+			if ( block->eof ) blksize = 0;
+			break;
+	        default: break;	/* Do nothing */
+		}
+		/* Send ACK */
+		xmit.opcode = htons(TFTP_ACK);
+		xmit.u.ack.block = htons(blockidx);
+		xmitlen = TFTP_MIN_PACKET;
+		udp_transmit ( server.sin_addr.s_addr, lport, server.sin_port,
+			       xmitlen, &xmit );
+	}
+	return ( block->data ? 1 : 0 );
+}
+
+/*
+ * Download a file via TFTP
+ *
+ */
+int tftp ( char *url __unused,
+	   struct sockaddr_in *server,
+	   char *file,
+	   int ( * process ) ( unsigned char *data,
+			       unsigned int blocknum,
+			       unsigned int len, int eof ) ) {
+	struct tftpreq_info_t request_data = {
+		.server = server,
+		.name = file,
+		.blksize = TFTP_MAX_PACKET,
+	};
+	struct tftpreq_info_t *request = &request_data;
+	struct tftpblk_info_t block;
+	int rc;
+
+	while ( tftp_block ( request, &block ) ) {
+		request = NULL; /* Send request only once */
+		rc = process ( block.data, block.block, block.len, block.eof );
+		if ( rc <= 0 ) return ( rc );
+	}
+	return 0;
+}
+
+struct protocol tftp_protocol __default_protocol = {
+	"tftp", tftp
+};