net: Move the checksum functions to lib/
These functions are used by code outside the network support, so move them
to lib/ to be more accessible.
Without this, the functions are only accessible in SPL/TPL only if
CONFIG_SPL/TPL_NET are defined. Many boards do not enable those option but
still want to do checksums in this format.
Fix up a few code-style nits while we are here.
Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/lib/Makefile b/lib/Makefile
index 7a713a5..6b7b9ce 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -78,7 +78,7 @@
ifdef CONFIG_SPL_BUILD
obj-$(CONFIG_SPL_YMODEM_SUPPORT) += crc16.o
obj-$(CONFIG_$(SPL_TPL_)HASH_SUPPORT) += crc16.o
-obj-$(CONFIG_SPL_NET_SUPPORT) += net_utils.o
+obj-y += net_utils.o
endif
obj-$(CONFIG_ADDR_MAP) += addr_map.o
obj-y += qsort.o
diff --git a/lib/net_utils.c b/lib/net_utils.c
index ed5044c..8af7782 100644
--- a/lib/net_utils.c
+++ b/lib/net_utils.c
@@ -56,3 +56,51 @@
addr = (*end) ? end + 1 : end;
}
}
+
+uint compute_ip_checksum(const void *vptr, uint nbytes)
+{
+ int sum, oddbyte;
+ const unsigned short *ptr = vptr;
+
+ sum = 0;
+ while (nbytes > 1) {
+ sum += *ptr++;
+ nbytes -= 2;
+ }
+ if (nbytes == 1) {
+ oddbyte = 0;
+ ((u8 *)&oddbyte)[0] = *(u8 *)ptr;
+ ((u8 *)&oddbyte)[1] = 0;
+ sum += oddbyte;
+ }
+ sum = (sum >> 16) + (sum & 0xffff);
+ sum += (sum >> 16);
+ sum = ~sum & 0xffff;
+
+ return sum;
+}
+
+uint add_ip_checksums(uint offset, uint sum, uint new)
+{
+ ulong checksum;
+
+ sum = ~sum & 0xffff;
+ new = ~new & 0xffff;
+ if (offset & 1) {
+ /*
+ * byte-swap the sum if it came from an odd offset; since the
+ * computation is endian-independent this works.
+ */
+ new = ((new >> 8) & 0xff) | ((new << 8) & 0xff00);
+ }
+ checksum = sum + new;
+ if (checksum > 0xffff)
+ checksum -= 0xffff;
+
+ return (~checksum) & 0xffff;
+}
+
+int ip_checksum_ok(const void *addr, uint nbytes)
+{
+ return !(compute_ip_checksum(addr, nbytes) & 0xfffe);
+}