1 files changed, 299 insertions, 0 deletions
diff --git a/libexec/tftpd/tftp-file.c b/libexec/tftpd/tftp-file.c
new file mode 100644
index 000000000000..405d1b9018c9
--- /dev/null
+++ b/libexec/tftpd/tftp-file.c
@@ -0,0 +1,299 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (C) 2008 Edwin Groothuis. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/types.h>
+#include <sys/ioctl.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+
+#include <netinet/in.h>
+#include <arpa/tftp.h>
+
+#include <assert.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <syslog.h>
+#include <unistd.h>
+
+#include "tftp-file.h"
+#include "tftp-utils.h"
+
+static FILE	*file;
+static int	convert;
+
+static char	convbuffer[66000];
+static int	gotcr = 0;
+
+static size_t
+convert_from_net(char *buffer, size_t count)
+{
+	size_t i, n;
+
+	/*
+	 * Convert all CR/LF to LF and all CR,NUL to CR
+	 */
+
+	n = 0;
+	for (i = 0; i < count; i++) {
+
+		if (gotcr == 0) {
+			convbuffer[n++] = buffer[i];
+			gotcr = (buffer[i] == '\r');
+			continue;
+		}
+
+		/* CR, NULL -> CR */
+		if (buffer[i] == '\0') {
+			gotcr = 0;
+			continue;
+		}
+
+		/* CR, LF -> LF */
+		if (buffer[i] == '\n') {
+			if (n == 0) {
+				if (ftell(file) != 0) {
+					int r = fseek(file, -1, SEEK_END);
+					assert(r == 0);
+					convbuffer[n++] = '\n';
+				} else {
+					/* This shouldn't happen */
+					tftp_log(LOG_ERR,
+					    "Received LF as first character");
+					abort();
+				}
+			} else
+				convbuffer[n-1] = '\n';
+			gotcr = 0;
+			continue;
+		}
+
+		/* Everything else just accept as is */
+		convbuffer[n++] = buffer[i];
+		gotcr = (buffer[i] == '\r');
+		continue;
+	}
+
+	return fwrite(convbuffer, 1, n, file);
+}
+
+static size_t
+convert_to_net(char *buffer, size_t count, int init)
+{
+	size_t i;
+	static size_t n = 0, in = 0;
+	static int newline = -1;
+
+	if (init) {
+		newline = -1;
+		n = 0;
+		in = 0;
+		return 0 ;
+	}
+
+	/*
+	 * Convert all LF to CR,LF and all CR to CR,NUL
+	 */
+	i = 0;
+
+	if (newline != -1) {
+		buffer[i++] = newline;
+		newline = -1;
+	}
+
+	while (i < count) {
+		if (n == in) {
+			/* When done we're done */
+			if (feof(file)) break;
+
+			/* Otherwise read another bunch */
+			in = fread(convbuffer, 1, count, file);
+			if (in == 0) break;
+			n = 0;
+		}
+
+		/* CR -> CR,NULL */
+		if (convbuffer[n] == '\r') {
+			buffer[i++] = '\r';
+			buffer[i++] = '\0';
+			n++;
+			continue;
+		}
+
+		/* LF -> CR,LF */
+		if (convbuffer[n] == '\n') {
+			buffer[i++] = '\r';
+			buffer[i++] = '\n';
+			n++;
+			continue;
+		}
+
+		buffer[i++] = convbuffer[n++];
+	}
+
+	if (i > count) {
+		/*
+		 * Whoops... that isn't allowed (but it will happen
+		 * when there is a CR or LF at the end of the buffer)
+		 */
+		newline = buffer[i-1];
+	}
+
+	if (i < count) {
+		/* We are done! */
+		return i;
+	} else
+		return count;
+
+}
+
+int
+write_init(int fd, FILE *f, const char *mode)
+{
+
+	if (f == NULL) {
+		file = fdopen(fd, "w");
+		if (file == NULL) {
+			int en = errno;
+			tftp_log(LOG_ERR, "fdopen() failed: %s",
+			    strerror(errno));
+			return en;
+		}
+	} else
+		file = f;
+	convert = !strcmp(mode, "netascii");
+	return 0;
+}
+
+size_t
+write_file(char *buffer, int count)
+{
+
+	if (convert == 0)
+		return fwrite(buffer, 1, count, file);
+
+	return convert_from_net(buffer, count);
+}
+
+int
+write_close(void)
+{
+
+	if (fclose(file) != 0) {
+		tftp_log(LOG_ERR, "fclose() failed: %s", strerror(errno));
+		return 1;
+	}
+	return 0;
+}
+
+off_t
+tell_file(void)
+{
+
+	return ftello(file);
+}
+
+int
+seek_file(off_t offset)
+{
+
+	return fseeko(file, offset, SEEK_SET);
+}
+
+int
+read_init(int fd, FILE *f, const char *mode)
+{
+
+	convert_to_net(NULL, 0, 1);
+	if (f == NULL) {
+		file = fdopen(fd, "r");
+		if (file == NULL) {
+			int en = errno;
+			tftp_log(LOG_ERR, "fdopen() failed: %s",
+			    strerror(errno));
+			return en;
+		}
+	} else
+		file = f;
+	convert = !strcmp(mode, "netascii");
+	return 0;
+}
+
+size_t
+read_file(char *buffer, int count)
+{
+
+	if (convert == 0)
+		return fread(buffer, 1, count, file);
+
+	return convert_to_net(buffer, count, 0);
+}
+
+int
+read_close(void)
+{
+
+	if (fclose(file) != 0) {
+		tftp_log(LOG_ERR, "fclose() failed: %s", strerror(errno));
+		return 1;
+	}
+	return 0;
+}
+
+
+/* When an error has occurred, it is possible that the two sides
+ * are out of synch.  Ie: that what I think is the other side's
+ * response to packet N is really their response to packet N-1.
+ *
+ * So, to try to prevent that, we flush all the input queued up
+ * for us on the network connection on our host.
+ *
+ * We return the number of packets we flushed (mostly for reporting
+ * when trace is active).
+ */
+
+int
+synchnet(int peer)			/* socket to flush */
+{
+	int i, j = 0;
+	char rbuf[MAXPKTSIZE];
+	struct sockaddr_storage from;
+	socklen_t fromlen;
+
+	while (1) {
+		(void) ioctl(peer, FIONREAD, &i);
+		if (i) {
+			j++;
+			fromlen = sizeof from;
+			(void) recvfrom(peer, rbuf, sizeof (rbuf), 0,
+				(struct sockaddr *)&from, &fromlen);
+		} else {
+			return(j);
+		}
+	}
+}