[Enterprise SONiC] ACL (Access Control List) Follow

An access control list (ACL) is an access control list based on an access control matrix. Access control sequences consist of access control entries (ACEs).

• ACL
• Control Plane ACL

Tested model & firmware version:

• Switch model name:
  DCS201 (AS5835-54X)

• Edgecore SONiC version:
  202006.4
  202012.0 ~ 202012.4
  202111.0 ~ 202111.1

Restriction:

• [202111.0] Known issue:
  • [SONIC-4734] the command of the ACL table for Control Plane CANNOT be applied.
  • [SONIC-4684] [Intel TF/TF2] Fix the problem that ACL with priority 1 will be matched as the highest rule. (This issue is fixed on 202111.1) 
• There is no SONiC command to add ACL rules.
• EC SONiC default configuration is "permit all".
• LAG's member port shall not be added to the ACL Tables or will be considered as invalid configuration and return fail.
• LAG ACL configurations will be automatically applied to all the LAG members.
• Control Plane ACL:
  • Support services for SSH/SNMP.
  • When the Control Plane ACL is running, the un-list service will be denied. i.e If the ACL table bind with SSH, SNMP will be denied.
  • There is “deny any any” in the last rules automatically.
  • Matching criteria("V" is valid matching criteria, "X" is invalid matching criteria)

• The ACL support table is shown below:
  

ACL

Procedure:

Step 1. Create an ACL table by CLI

admin@sonic:~$ sudo config acl add table --help
Usage: config acl add table [OPTIONS] <table_name> <table_type>

Add ACL table

Options:
-d, --description TEXT
-p, --ports TEXT
-s, --stage [ingress|egress]
-S, --services TEXT
-?, -h, --help Show this message and exit.
admin@sonic:~$ sudo config acl add table ACL_ETH0 L3 --description 'drop_1.0' --stage 'ingress' --ports 'Ethernet0'

Note:

• The "policy_desc" is a string about the description of ACL table.
• The "stage" is about the ACL direction.
  • Ingress
  • egress
•  Support “table_type”:
  • L3
  • L3V6
  • MIRROR(About the MIRROR, please refer to this article.)
  • CTRLPLANE(refer to Service ACL)

Step 2. Check ACL table by SONiC command. 

admin@sonic:~$ show acl table 
Name      Type    Binding    Description    Stage
--------  ------  ---------  -------------  -------
ACL_ETH0  L3      Ethernet0  drop_1.0       ingress

Step 3. Create the JSON file(ACE.json) for ACL rules and apply with command “config load” 

admin@sonic:~$ sudo vi ACE.json
{
    "ACL_RULE": {
        "ACL_ETH0|ACE_DROP2": {
            "PACKET_ACTION": "DROP",
            "PRIORITY": "1",
            "DST_IP": "192.168.1.11/32",
            "IP_TYPE": "IP"
     },
        "ACL_ETH0|ACE_DROP1": {
            "PACKET_ACTION": "DROP",
            "PRIORITY": "2",
            "SRC_IP": "192.168.1.10/32",
            "IP_TYPE": "IP",
            "L4_SRC_PORT": "53"
        }
    }
}
admin@sonic:~$ sudo config load ACE.json -y

Note:

• Key "ACL_ETH0|ACE_DROP2" and "ACL_ETH0|ACE_DROP1" are the names of rules of ACL ACL_ETH0. 
• If key "types" of ACL TABLE is L3 or L3V6,
  • Key in ACL rule is "PACKET_ACTION"
  • The value of "PACKET_ACTION" is FORWARD or DROP.
• If key "types" of ACL table is MIRROR,
  • Key in ACL rule is "MIRROR_ACTION"
  • The value of "MIRROR_ACTION" is the name of mirror session
    
• The number of priority is bigger which means priority is high. 
  Take the above example, the priority 2 will match first.
  
  • Caution: There's a known issue on version 202111.0, the priority of the Tofino platform(Wedge100bf series, 9516-32D), The number of priority is smaller which means priority is high. (This issue is fixed on 202111.1)
    
• Here are the values for "IP_TYPE": 
  

  ANY	Filter IPv4, IPv6, Ether type
  IP	Filter IPv4, IPv6
  NON_IP	Filter Ether type only
  IPV4ANY	Filter IPv4 only
  NON_IPv4	Filter IPv6, Ether type
  IPV6ANY	Filter IPv6 only
  NON_IPv6	Filter IPv4, Ether type
  ARP	Filter ARP request, reply
  ARP_REQUEST	Filter ARP request only
  ARP_REPLY	Filter ARP reply only

  Caution: NON_IP, NON_IPv4, NON_IPv6, ARP_REQUEST, ARP_REPLY could not work now.
• Other keys(parameters):

1. DST_IP example: "DST_IP": "192.168.1.10/32"
2. SRC_IPV6 example: "SRC_IPV6": "2001::db:1"
   Caution: The type of the ACL table should be modified to "L3V6"
3. DST_IPV6 example: "DST_IPV6": "2001::db:2"
   Caution: The type of the ACL table should be modified to "L3V6"
4. ETHER_TYPE example:  "ETHER_TYPE": "0x842" or "ETHER_TYPE": "2114" 
5. L4_SRC_PORT example: "L4_SRC_PORT": "53" 
6. L4_DST_PORT example: "L4_DST_PORT": "53" 
7. IP_PROTOCOL example: "IP_PROTOCOL": "1"
   
8. L4_SRC_PORT_RANGE example: "L4_SRC_PORT_RANGE": "1028-4096"
   Caution: Egress doesn't support it.
9. L4_DST_PORT_RANGE example: "L4_DST_PORT_RANGE": "1028-4096"
   Caution: Egress doesn't support it.
   
10. ICMP_TYPE example: "ICMP_TYPE": "0"
11. ICMPV6_TYPE example: "ICMPV6_TYPE": "128"
    Caution: The type of the ACL table should be modified to "L3V6"
    
12. TCP_FLAGS example: "TCP_FLAGS": "16/255"
    Note:
    FIN =   0x01     "TCP_FLAGS": "0x01/63"
    SYN = 0x02      "TCP_FLAGS": "0x02/63"
    RST = 0x04      "TCP_FLAGS": "0x04/63"
    PSH = 0x08      "TCP_FLAGS": "0x08/63"
    ACK = 0x10      "TCP_FLAGS": "0x10/63"
    URG = 0x20     "TCP_FLAGS": "0x20/63"
    Caution: Not support for filtering Congestion Window Reduced (CWR) and ECN-Echo (ECE)
13. VLAN_ID, example: "VLAN_ID": "10"     
    
    

Step 4. Check ACL rules by SONiC command

admin@sonic:~$ show acl rule 
Table     Rule       Priority    Action    Match
--------  ---------  ----------  --------  -----------------------
ACL_ETH0  ACE_DROP1  2           DROP      IP_TYPE: IP
                                           L4_SRC_PORT: 53
                                           SRC_IP: 192.168.1.10/32
ACL_ETH0  ACE_DROP2  1           DROP      DST_IP: 192.168.1.11/32
                                           IP_TYPE: IP 

Control Plane ACL

Procedure:

Step 1. Create an Service ACL table by CLI

admin@sonic:~$ sudo config acl add table CTRL CTRLPLANE --help
Usage: config acl add table [OPTIONS] <table_name> <table_type>

Add ACL table

Options:
-d, --description TEXT
-p, --ports TEXT
-s, --stage [ingress|egress]
-S, --services TEXT
-?, -h, --help Show this message and exit.
admin@sonic:~$
admin@sonic:~$ sudo config acl add table CTRL CTRLPLANE --description “CTRLPANE ACL” --services “SSH,SNMP”

Note. In 202006 branch, the service ACL table do not have CLI. Please create a JSON file and apply by “config load”

admin@sonic:~$sudo vi service_table.json
{
“ACL_TABLE”: {
        “CTRL”: {
            “policy_desc”: “CTRLPLANE ACL”,
            “services”: [
                    “SSH”,
                    “SNMP”
            ],
            “type”: “CTRLPLANE”
        }
    }
}
admin@sonic:~$ sudo config load service_table.json -y

Step 2. Check ACL table by SONiC command. 

admin@sonic:~$ show acl table 
Name   Type      Binding   Description   Stage
------ --------- --------- ------------- -------
CTRL   CTRLPLANE SNMP      CTRLPANE ACL  ingress
                 SSH

Step 3. Create the JSON file(CTRL_ACE.json) for ACL rules and apply with command “config load” 

admin@sonic:~$ sudo vi CTRL_ACE.json
{
    "ACL_RULE": {
        "CTRL|ACE_ACCEPT": {
            "PACKET_ACTION": "ACCEPT",
            "PRIORITY": "2",
            "SRC_IP": "192.168.1.10/32"
        }
    }
}
admin@sonic:~$ sudo config load CTRL_ACE.json -y

Step 4. Check ACL rules by SONiC command

admin@sonic:~$ show acl rule 
Table   Rule        Priority   Action   Match
------- ----------- ---------- -------- ------------------------
CTRL    ACE_ACCEPT  2          ACCEPT   SRC_IP: 192.168.1.10/32