diff options
| author | Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk> | 2017-12-15 18:41:43 +0000 |
|---|---|---|
| committer | Jason Wang <jasowang@redhat.com> | 2017-12-22 09:55:03 +0800 |
| commit | eaba8f34f0dac5e9296df9c2046d9601264c46a4 (patch) | |
| tree | 47497a0be3a2e626b1dcc62eb36d0cc64f36e898 | |
| parent | d62644b46a86bce2c069af7122501e3ffd349d3c (diff) | |
net: move CRC32 calculation from compute_mcast_idx() into its own net_crc32() function
Separate out the standard ethernet CRC32 calculation into a new net_crc32()
function, renaming the constant POLYNOMIAL to POLYNOMIAL_BE to make it clear
that this is a big-endian CRC32 calculation.
As part of the constant rename, remove the duplicate definition of POLYNOMIAL
from eepro100.c and use the new POLYNOMIAL_BE constant instead.
Once this is complete remove the existing CRC32 implementation from
compute_mcast_idx() and call the new net_crc32() function in its place.
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Jason Wang <jasowang@redhat.com>
| -rw-r--r-- | hw/net/eepro100.c | 4 | ||||
| -rw-r--r-- | include/net/net.h | 3 | ||||
| -rw-r--r-- | net/net.c | 16 |
3 files changed, 14 insertions, 9 deletions
diff --git a/hw/net/eepro100.c b/hw/net/eepro100.c index 1c0def555b..71cddfece4 100644 --- a/hw/net/eepro100.c +++ b/hw/net/eepro100.c @@ -323,8 +323,6 @@ static const uint16_t eepro100_mdi_mask[] = { 0xffff, 0xffff, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, }; -#define POLYNOMIAL 0x04c11db6 - static E100PCIDeviceInfo *eepro100_get_class(EEPRO100State *s); /* From FreeBSD (locally modified). */ @@ -342,7 +340,7 @@ static unsigned e100_compute_mcast_idx(const uint8_t *ep) crc <<= 1; b >>= 1; if (carry) { - crc = ((crc ^ POLYNOMIAL) | carry); + crc = ((crc ^ POLYNOMIAL_BE) | carry); } } } diff --git a/include/net/net.h b/include/net/net.h index 1c55a93588..586098cb94 100644 --- a/include/net/net.h +++ b/include/net/net.h @@ -227,7 +227,8 @@ NetClientState *net_hub_port_find(int hub_id); void qdev_set_nic_properties(DeviceState *dev, NICInfo *nd); -#define POLYNOMIAL 0x04c11db6 +#define POLYNOMIAL_BE 0x04c11db6 +uint32_t net_crc32(const uint8_t *p, int len); unsigned compute_mcast_idx(const uint8_t *ep); #define vmstate_offset_macaddr(_state, _field) \ @@ -1581,25 +1581,31 @@ int net_client_parse(QemuOptsList *opts_list, const char *optarg) /* From FreeBSD */ /* XXX: optimize */ -unsigned compute_mcast_idx(const uint8_t *ep) +uint32_t net_crc32(const uint8_t *p, int len) { uint32_t crc; int carry, i, j; uint8_t b; crc = 0xffffffff; - for (i = 0; i < 6; i++) { - b = *ep++; + for (i = 0; i < len; i++) { + b = *p++; for (j = 0; j < 8; j++) { carry = ((crc & 0x80000000L) ? 1 : 0) ^ (b & 0x01); crc <<= 1; b >>= 1; if (carry) { - crc = ((crc ^ POLYNOMIAL) | carry); + crc = ((crc ^ POLYNOMIAL_BE) | carry); } } } - return crc >> 26; + + return crc; +} + +unsigned compute_mcast_idx(const uint8_t *ep) +{ + return net_crc32(ep, ETH_ALEN) >> 26; } QemuOptsList qemu_netdev_opts = { |