/* Returns true if two masked 24 bit values match */
static inline bool
match_mask24(uint8_t *a, uint8_t *am, uint8_t *b) {
return (match_mask16(a, am, b) &&
match_mask8(a+2, am+2, b+2));
}
/* Returns true if two masked 48 bit values match */
static inline bool
match_mask48(uint8_t *a, uint8_t *am, uint8_t *b) {
return (match_mask32(a, am, b) &&
match_mask16(a+4, am+4, b+4));
}
/* Returns true if the fields in *packet matches the flow entry in *flow_match */
bool
packet_match(struct ofl_match *flow_match, struct ofl_match *packet, struct ofl_exp *exp){
struct ofl_match_tlv *f;
struct ofl_match_tlv *packet_f;
bool has_mask;
int field_len;
int packet_header;
uint8_t *flow_val, *flow_mask= NULL;
uint8_t *packet_val;
if (flow_match->header.length == 0)
return true;
/* Loop over the flow entry's match fields */
HMAP_FOR_EACH(f, struct ofl_match_tlv, hmap_node, &flow_match->match_fields)
{
/* Check presence of match field in packet */
has_mask = OXM_HASMASK(f->header);
packet_header = f->header;
switch (OXM_VENDOR(f->header))
{
case(OFPXMC_OPENFLOW_BASIC):
field_len = OXM_LENGTH(f->header);
flow_val = f->value;
if (has_mask) {
/* Clear the has_mask bit and divide the field_len by two in the packet field header */
field_len /= 2;
packet_header &= 0xfffffe00;
packet_header |= field_len;
flow_mask = f->value + field_len;
}
break;
case(OFPXMC_EXPERIMENTER):
if (exp == NULL || exp->field == NULL || exp->field->match == NULL) {
VLOG_WARN(LOG_MODULE,"Received match is experimental, but no callback was given.");
ofl_error(OFPET_BAD_MATCH, OFPBMC_BAD_TYPE);
}
exp->field->match(f, &packet_header, &field_len, &flow_val, &flow_mask);
break;
default:
break;
}
/* Lookup the packet header */
packet_f = oxm_match_lookup(packet_header, packet);
if (!packet_f) {
if (f->header==OXM_OF_VLAN_VID &&
*((uint16_t *) f->value)==OFPVID_NONE) {
/* There is no VLAN tag, as required */
continue;
}
return false;
}
/* Compare the flow and packet field values, considering the mask, if any */
switch (OXM_VENDOR(f->header))
{
case(OFPXMC_OPENFLOW_BASIC):
packet_val = packet_f->value;
break;
case(OFPXMC_EXPERIMENTER):
if (exp == NULL || exp->field == NULL || exp->field->compare == NULL) {
VLOG_WARN(LOG_MODULE,"Received match is experimental, but no callback was given.");
ofl_error(OFPET_BAD_MATCH, OFPBMC_BAD_TYPE);
}
exp->field->compare(f, packet_f, &packet_val);
break;
default:
break;
}
switch (field_len) {
case 1:
if (has_mask) {
if (!match_mask8(flow_val, flow_mask, packet_val))
return false;
}
else {
if (!match_8(flow_val, packet_val))
return false;
}
break;
case 2:
switch (packet_header) {
case OXM_OF_VLAN_VID: {
/* Special handling for VLAN ID */
uint16_t flow_vlan_id = *((uint16_t*) flow_val);
if (flow_vlan_id == OFPVID_NONE) {
/* Packet has a VLAN tag when none should be there */
return false;
} else if (flow_vlan_id == OFPVID_PRESENT) {
/* Any VLAN ID is acceptable. No further checks */
} else {
/* Check the VLAN ID */
flow_vlan_id &= VLAN_VID_MASK;
if (has_mask){
if (!match_mask16((uint8_t*) &flow_vlan_id, flow_mask, packet_val)){
return false;
}
}
else {
if (!match_16((uint8_t*) &flow_vlan_id, packet_val)){
return false;
}
}
}
break;
}
case OXM_OF_IPV6_EXTHDR: {
/* Special handling for IPv6 Extension header */
uint16_t flow_eh = *((uint16_t *) flow_val);
uint16_t packet_eh = *((uint16_t *) packet_val);
if ((flow_eh & packet_eh) != flow_eh) {
/* The packet doesn't have all extension headers specified in the flow */
return false;
}
break;
}
default:
if (has_mask) {
if (!match_mask16(flow_val, flow_mask, packet_val))
return false;
}
else {
if (!match_16(flow_val, packet_val))
return false;
}
break;
}
break;
case 3:
if (has_mask) {
if (!match_mask24(flow_val, flow_mask, packet_val))
return false;
}
else {
if (!match_24(flow_val, packet_val))
return false;
}
break;
case 4:
if (has_mask) {
if (!match_mask32(flow_val, flow_mask, packet_val))
return false;
}
else {
if (!match_32(flow_val, packet_val))
return false;
}
break;
case 6:
if (has_mask) {
if (!match_mask48(flow_val, flow_mask, packet_val))
return false;
}
else {
if (!match_48(flow_val, packet_val))
return false;
}
break;
case 8:
if (has_mask) {
if (!match_mask64(flow_val, flow_mask, packet_val))
return false;
}
else {
if (!match_64(flow_val, packet_val))
return false;
}
break;
case 16:
if (has_mask) {
if (!match_mask128(flow_val, flow_mask, packet_val))
return false;
}
else {
if (!match_128(flow_val, packet_val))
return false;
}
break;
default:
/* Should never happen */
break;
}
}
/* If we get here, all match fields in the flow entry matched the packet */
return true;
}
/* Returns true if the fields in *packet matches the flow entry in *flow_match */
bool
packet_match(struct ofl_match *flow_match, struct ofl_match *packet) {
struct ofl_match_tlv *f;
struct ofl_match_tlv *packet_f;
bool has_mask;
int field_len;
int packet_header;
uint8_t *flow_val, *flow_mask=0;
uint8_t *packet_val;
if (flow_match->header.length == 0) {
return true;
}
/* Loop over the flow entry's match fields */
HMAP_FOR_EACH(f, struct ofl_match_tlv, hmap_node, &flow_match->match_fields)
{
/* Check presence of match field in packet */
has_mask = OXM_HASMASK(f->header);
field_len = OXM_LENGTH(f->header);
packet_header = f->header;
flow_val = f->value;
if (has_mask) {
/* Clear the has_mask bit and divide the field_len by two in the packet field header */
field_len /= 2;
packet_header &= 0xfffffe00;
packet_header |= field_len;
flow_mask = f->value + field_len;
}
char *f_str = ofl_structs_oxm_tlv_to_string(f);
free(f_str);
/* Lookup the packet header */
packet_f = oxm_match_lookup(packet_header, packet);
if (!packet_f) {
if (f->header==OXM_OF_VLAN_VID &&
*((uint16_t *) f->value)==OFPVID_NONE) {
/* There is no VLAN tag, as required */
continue;
}
return false;
}
/* Compare the flow and packet field values, considering the mask, if any */
packet_val = packet_f->value;
switch (field_len) {
case 1:
if (has_mask) {
if (!match_mask8(flow_val, flow_mask, packet_val))
return false;
}
else {
if (!match_8(flow_val, packet_val))
return false;
}
break;
case 2:
switch (packet_header) {
case OXM_OF_VLAN_VID: {
/* Special handling for VLAN ID */
uint16_t flow_vlan_id = *((uint16_t *) flow_val);
if (flow_vlan_id == OFPVID_NONE) {
/* Packet has a VLAN tag when none should be there */
return false;
} else if (flow_vlan_id == OFPVID_PRESENT) {
/* Any VLAN ID is acceptable. No further checks */
} else {
/* Check the VLAN ID */
if (!match_16(flow_val, packet_val))
return false;
}
break;
}
case OXM_OF_IPV6_EXTHDR: {
/* Special handling for IPv6 Extension header */
uint16_t flow_eh = *((uint16_t *) flow_val);
uint16_t packet_eh = *((uint16_t *) packet_val);
if ((flow_eh & packet_eh) != flow_eh) {
/* The packet doesn't have all extension headers specified in the flow */
return false;
}
break;
}
default:
if (has_mask) {
if (!match_mask16(flow_val, flow_mask, packet_val))
return false;
}
else {
if (!match_16(flow_val, packet_val))
return false;
}
break;
}
break;
case 4:
if (has_mask) {
if (!match_mask32(flow_val, flow_mask, packet_val))
return false;
}
else {
if (!match_32(flow_val, packet_val))
return false;
}
break;
case 6:
if (has_mask) {
if (!match_mask48(flow_val, flow_mask, packet_val))
return false;
}
else {
if (!match_48(flow_val, packet_val))
return false;
}
break;
case 8:
if (has_mask) {
if (!match_mask64(flow_val, flow_mask, packet_val))
return false;
}
else {
if (!match_64(flow_val, packet_val))
return false;
}
break;
case 16:
if (has_mask) {
if (!match_mask128(flow_val, flow_mask, packet_val))
return false;
}
else {
if (!match_128(flow_val, packet_val))
return false;
}
break;
default:
/* Should never happen */
break;
}
}
/* If we get here, all match fields in the flow entry matched the packet */
return true;
}