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Diffstat (limited to 'com32/sysdump/be_tftp.c')
-rw-r--r--com32/sysdump/be_tftp.c127
1 files changed, 127 insertions, 0 deletions
diff --git a/com32/sysdump/be_tftp.c b/com32/sysdump/be_tftp.c
new file mode 100644
index 00000000..17275b16
--- /dev/null
+++ b/com32/sysdump/be_tftp.c
@@ -0,0 +1,127 @@
+/*
+ * TFTP data output backend
+ */
+
+#include <string.h>
+#include <syslinux/pxe.h>
+#include <syslinux/config.h>
+#include <netinet/in.h>
+#include <sys/times.h>
+
+#include "backend.h"
+
+enum tftp_opcode {
+ TFTP_RRQ = 1,
+ TFTP_WRQ = 2,
+ TFTP_DATA = 3,
+ TFTP_ACK = 4,
+ TFTP_ERROR = 5,
+};
+
+static uint16_t local_port = 0x4000;
+
+static int send_ack_packet(struct backend *be, const void *pkt, size_t len)
+{
+ com32sys_t ireg, oreg;
+ t_PXENV_UDP_WRITE *uw = __com32.cs_bounce;
+ t_PXENV_UDP_READ *ur = __com32.cs_bounce;
+ clock_t start;
+ static const clock_t timeouts[] = {
+ 2, 2, 3, 3, 4, 5, 6, 7, 9, 10, 12, 15, 18, 21, 26, 31,
+ 37, 44, 53, 64, 77, 92, 110, 132, 159, 191, 229, 0
+ };
+ const clock_t *timeout;
+
+ memset(&ireg, 0, sizeof ireg);
+ ireg.eax.w[0] = 0x0009;
+
+ for (timeout = timeouts ; *timeout ; timeout++) {
+ memset(uw, 0, sizeof uw);
+ memcpy(uw+1, pkt, len);
+ uw->ip = be->tftp.srv_ip;
+ uw->src_port = be->tftp.my_port;
+ uw->dst_port = be->tftp.srv_port ? be->tftp.srv_port : htons(69);
+ uw->buffer_size = len;
+ uw->buffer = FAR_PTR(uw+1);
+
+ ireg.ebx.w[0] = PXENV_UDP_WRITE;
+ ireg.es = SEG(uw);
+ ireg.edi.w[0] = OFFS(uw);
+
+ __intcall(0x22, &ireg, &oreg);
+
+ start = times(NULL);
+
+ do {
+ memset(ur, 0, sizeof ur);
+ ur->src_ip = be->tftp.srv_ip;
+ ur->dest_ip = be->tftp.my_ip;
+ ur->s_port = be->tftp.srv_port;
+ ur->d_port = be->tftp.my_port;
+ ur->buffer_size = __com32.cs_bounce_size - sizeof *ur;
+ ur->buffer = FAR_PTR(ur+1);
+
+ ireg.ebx.w[0] = PXENV_UDP_READ;
+ ireg.es = SEG(ur);
+ ireg.edi.w[0] = OFFS(ur);
+ __intcall(0x22, &ireg, &oreg);
+
+ if (!(oreg.eflags.l & EFLAGS_CF) &&
+ ur->status == PXENV_STATUS_SUCCESS &&
+ be->tftp.srv_ip == ur->src_ip &&
+ (be->tftp.srv_port == 0 ||
+ be->tftp.srv_port == ur->s_port)) {
+ uint16_t *xb = (uint16_t *)(ur+1);
+ if (ntohs(xb[0]) == TFTP_ACK &&
+ ntohs(xb[1]) == be->tftp.seq) {
+ be->tftp.srv_port = ur->s_port;
+ return 0; /* All good! */
+ } else if (ntohs(xb[1]) == TFTP_ERROR) {
+ return -1; /* All bad! */
+ }
+ }
+ } while ((clock_t)(times(NULL) - start) < *timeout);
+ }
+
+ return -1; /* No success... */
+}
+
+static int be_tftp_open(struct backend *be, const char *argv[])
+{
+ char buffer[512+4+6];
+ int nlen;
+ const union syslinux_derivative_info *sdi =
+ syslinux_derivative_info();
+
+ be->tftp.my_ip = sdi->pxe.myip;
+ be->tftp.my_port = htons(local_port++);
+ be->tftp.srv_ip = pxe_dns(argv[1]);
+ be->tftp.srv_port = 0;
+ be->tftp.seq = 0;
+
+ buffer[0] = 0;
+ buffer[1] = TFTP_WRQ;
+ nlen = strlcpy(buffer+2, argv[0], 512);
+ memcpy(buffer+3+nlen, "octet", 6);
+
+ return send_ack_packet(be, buffer, 2+nlen+1+6);
+}
+
+static int be_tftp_write(struct backend *be, const char *buf, size_t len)
+{
+ char buffer[512+4];
+
+ buffer[0] = 0;
+ buffer[1] = TFTP_DATA;
+ *((uint16_t *)(buffer+2)) = htons(++be->tftp.seq);
+ memcpy(buffer+4, buf, len);
+
+ return send_ack_packet(be, buffer, len+4);
+}
+
+struct backend be_tftp = {
+ .name = "tftp",
+ .blocksize = 512,
+ .open = be_tftp_open,
+ .write = be_tftp_write,
+};