diff mbox

[U-Boot,14/14] tools: Add tool to add crc8 to a mac address

Message ID 20161125153032.14617-15-oliver@schinagl.nl
State Accepted
Commit c25f01a63ac21ddfa522d972b09a0e9e5ab4b4cd
Delegated to: Joe Hershberger
Headers show

Commit Message

Olliver Schinagl Nov. 25, 2016, 3:30 p.m. UTC 
This patch adds a little tool that takes a generic MAC address and
generates a CRC byte for it. The output is the full MAC address without
any separators, ready written into an EEPROM.

Signed-off-by: Olliver Schinagl <o.schinagl@ultimaker.com>
Signed-off-by: Olliver Schinagl <oliver@schinagl.nl>
---
 tools/.gitignore        |  1 +
 tools/Makefile          |  4 +++
 tools/gen_ethaddr_crc.c | 75 +++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 80 insertions(+)
 create mode 100644 tools/gen_ethaddr_crc.c

Comments

Joe Hershberger Nov. 30, 2016, 8:36 p.m. UTC | #1 
On Fri, Nov 25, 2016 at 9:30 AM, Olliver Schinagl <oliver@schinagl.nl> wrote:
> This patch adds a little tool that takes a generic MAC address and
> generates a CRC byte for it. The output is the full MAC address without
> any separators, ready written into an EEPROM.
>
> Signed-off-by: Olliver Schinagl <o.schinagl@ultimaker.com>
> Signed-off-by: Olliver Schinagl <oliver@schinagl.nl>

Seems simple enough.

Acked-by: Joe Hershberger <joe.hershberger@ni.com>
Joe Hershberger Feb. 9, 2017, 4:26 p.m. UTC | #2 
Hi oliver@schinagl.nl,

https://patchwork.ozlabs.org/patch/699397/ was applied to u-boot-net.git.

Thanks!
-Joe
diff mbox

Patch

diff --git a/tools/.gitignore b/tools/.gitignore
index cb1e722..0d1f076 100644
--- a/tools/.gitignore
+++ b/tools/.gitignore
@@ -6,6 +6,7 @@ 
 /fit_check_sign
 /fit_info
 /gen_eth_addr
+/gen_ethaddr_crc
 /ifdtool
 /img2srec
 /kwboot
diff --git a/tools/Makefile b/tools/Makefile
index 06afdb0..4879ded 100644
--- a/tools/Makefile
+++ b/tools/Makefile
@@ -43,6 +43,10 @@  envcrc-objs := envcrc.o lib/crc32.o common/env_embedded.o lib/sha1.o
 hostprogs-$(CONFIG_CMD_NET) += gen_eth_addr
 HOSTCFLAGS_gen_eth_addr.o := -pedantic
 
+hostprogs-$(CONFIG_CMD_NET) += gen_ethaddr_crc
+gen_ethaddr_crc-objs := gen_ethaddr_crc.o lib/crc8.o
+HOSTCFLAGS_gen_ethaddr_crc.o := -pedantic
+
 hostprogs-$(CONFIG_CMD_LOADS) += img2srec
 HOSTCFLAGS_img2srec.o := -pedantic
 
diff --git a/tools/gen_ethaddr_crc.c b/tools/gen_ethaddr_crc.c
new file mode 100644
index 0000000..fe9896d
--- /dev/null
+++ b/tools/gen_ethaddr_crc.c
@@ -0,0 +1,75 @@ 
+/*
+ * (C) Copyright 2016
+ * Olliver Schinagl <oliver@schinagl.nl>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <ctype.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <u-boot/crc.h>
+
+#define ARP_HLEN 6 /* Length of hardware address */
+#define ARP_HLEN_ASCII (ARP_HLEN * 2) + (ARP_HLEN - 1) /* with separators */
+#define ARP_HLEN_LAZY (ARP_HLEN * 2) /* separatorless hardware address length */
+
+uint8_t nibble_to_hex(const char *nibble, bool lo)
+{
+	return (strtol(nibble, NULL, 16) << (lo ? 0 : 4)) & (lo ? 0x0f : 0xf0);
+}
+
+int process_mac(const char *mac_address)
+{
+	uint8_t ethaddr[ARP_HLEN + 1] = { 0x00 };
+	uint_fast8_t i = 0;
+
+	while (*mac_address != '\0') {
+		char nibble[2] = { 0x00, '\n' }; /* for strtol */
+
+		nibble[0] = *mac_address++;
+		if (isxdigit(nibble[0])) {
+			if (isupper(nibble[0]))
+				nibble[0] = tolower(nibble[0]);
+			ethaddr[i >> 1] |= nibble_to_hex(nibble, (i % 2) != 0);
+			i++;
+		}
+	}
+
+	for (i = 0; i < ARP_HLEN; i++)
+		printf("%.2x", ethaddr[i]);
+	printf("%.2x\n", crc8(0, ethaddr, ARP_HLEN));
+
+	return 0;
+}
+
+void print_usage(char *cmdname)
+{
+	printf("Usage: %s <mac_address>\n", cmdname);
+	puts("<mac_address> may be with or without separators.");
+	puts("Valid seperators are ':' and '-'.");
+	puts("<mac_address> digits are in base 16.\n");
+}
+
+int main(int argc, char *argv[])
+{
+	if (argc < 2) {
+		print_usage(argv[0]);
+		return 1;
+	}
+
+	if (!((strlen(argv[1]) == ARP_HLEN_ASCII) || (strlen(argv[1]) == ARP_HLEN_LAZY))) {
+		puts("The MAC address is not valid.\n");
+		print_usage(argv[0]);
+		return 1;
+	}
+
+	if (process_mac(argv[1])) {
+		puts("Failed to calculate the MAC's checksum.");
+		return 1;
+	}
+
+	return 0;
+}