From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:54957) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dii3p-0006Pi-9R for qemu-devel@nongnu.org; Fri, 18 Aug 2017 10:15:42 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dii3l-0006N5-95 for qemu-devel@nongnu.org; Fri, 18 Aug 2017 10:15:41 -0400 Received: from chuckie.co.uk ([82.165.15.123]:57467 helo=s16892447.onlinehome-server.info) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dii3l-00068E-1h for qemu-devel@nongnu.org; Fri, 18 Aug 2017 10:15:37 -0400 From: Mark Cave-Ayland Date: Fri, 18 Aug 2017 15:15:06 +0100 Message-Id: <1503065708-28277-3-git-send-email-mark.cave-ayland@ilande.co.uk> In-Reply-To: <1503065708-28277-1-git-send-email-mark.cave-ayland@ilande.co.uk> References: <1503065708-28277-1-git-send-email-mark.cave-ayland@ilande.co.uk> Subject: [Qemu-devel] [PATCH 2/4] net: introduce net_crc32_le() function List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org, jasowang@redhat.com This provides a standard ethernet CRC32 little-endian implementation. Signed-off-by: Mark Cave-Ayland --- include/net/net.h | 2 ++ net/net.c | 22 ++++++++++++++++++++++ 2 files changed, 24 insertions(+) diff --git a/include/net/net.h b/include/net/net.h index 586098c..4afac1a 100644 --- a/include/net/net.h +++ b/include/net/net.h @@ -228,7 +228,9 @@ NetClientState *net_hub_port_find(int hub_id); void qdev_set_nic_properties(DeviceState *dev, NICInfo *nd); #define POLYNOMIAL_BE 0x04c11db6 +#define POLYNOMIAL_LE 0xedb88320 uint32_t net_crc32(const uint8_t *p, int len); +uint32_t net_crc32_le(const uint8_t *p, int len); unsigned compute_mcast_idx(const uint8_t *ep); #define vmstate_offset_macaddr(_state, _field) \ diff --git a/net/net.c b/net/net.c index a856907..c99e705 100644 --- a/net/net.c +++ b/net/net.c @@ -1590,6 +1590,28 @@ uint32_t net_crc32(const uint8_t *p, int len) return crc; } +uint32_t net_crc32_le(const uint8_t *p, int len) +{ + uint32_t crc; + int carry, i, j; + uint8_t b; + + crc = 0xffffffff; + for (i = 0; i < len; i++) { + b = *p++; + for (j = 0; j < 8; j++) { + carry = (crc & 0x1) ^ (b & 0x01); + crc >>= 1; + b >>= 1; + if (carry) { + crc = crc ^ POLYNOMIAL_LE; + } + } + } + + return crc; +} + unsigned compute_mcast_idx(const uint8_t *ep) { return net_crc32(ep, 6) >> 26; -- 1.7.10.4