These docs are for Cribl Stream 4.8 and are no longer actively maintained.

See the latest version (4.13).

C.Net – Network Methods

C.Net.cidrMatch()

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Net.cidrMatch(cidrIpRange: string, ipAddress: string): boolean

Determines whether the supplied IPv4 or IPv6 ipAddress is inside the range of addresses identified by cidrIpRange.

Examples

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(IPv4): C.Net.cidrMatch('10.0.0.0/24', '10.0.0.100') returns true.

(IPv6): C.Net.cidrMatch('2001:db8::/32', '2001:db8:0:0:0:ffff:0:0') returns true.

C.Net.communityIDv1()

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Net.communityIDv1(sourceIP: string, destIP: string, sourcePort: number | undefined, destPort: number | undefined, proto: string | number, seed: number = 0): string

Calculates the Community ID for a given network flow. A Community ID is a unique identifier that is reversible – it is the same for both sides of a connection. It is calculated based on source and destination IP addresses, ports, a protocol, and (optionally) a seed (explained below). When the protocol is ICMP, the Community ID will be reversible provided that the network flow uses types with a clear request/response relationship (for example, Echo and Echo Reply).

Usage

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This method returns a Base64-encoded string.

Provide IP addresses – whether IPv4 or IPv6 – as strings.

When the protocol is ICMP (v4 or v6), sourcePort corresponds to message type and destPort corresponds to message code. For other Layer 3 protocols, sourcePort and destPort should be undefined.

You can specify proto either as a number (recommended, to avoid ambiguity) or a string.

• If a string, proto must be the desired protocol’s keyword as specified in the IANA protocol registry.
• For network flows coming from the Cribl Stream NetFlow Source, use the protocol name as-is – the Source will provide it in correct form.

The optional seed parameter defaults to 0. If you want to generate different Community IDs for different use cases within the same flow, change seed to a different value for each use case.

Examples

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Bidirectional TCP flow using the protocol number.

// Protocol number 6 is TCP

C.Net.communityIDv1('1.2.3.4','5.6.7.8',1122,3344,6)
// '1:wCb3OG7yAFWelaUydu0D+125CLM='

C.Net.communityIDv1('5.6.7.8','1.2.3.4',3344,1122,6)
// '1:wCb3OG7yAFWelaUydu0D+125CLM='

Bidirectional UDP flow using the protocol name.

C.Net.communityIDv1('1.2.3.4','5.6.7.8',1122,3344,'udp')
// '1:0Mu9InQx6z4ZiCZM/7HXi2WMhOg='

C.Net.communityIDv1('5.6.7.8','1.2.3.4',3344,1122,'udp')
// '1:0Mu9InQx6z4ZiCZM/7HXi2WMhOg='

ICMP Echo/Echo Reply flow.

// Protocol number 1 is ICMP
// Echo is Type=8, Code=0
// Echo Reply is Type=0, Code=0

// Echo (equivalent of request)
C.Net.communityIDv1('1.2.3.4','5.6.7.8',8,0,1)
// '1:crodRHL2FEsHjbv3UkRrfbs4bZ0='

// Echo Reply (equivalent of response)
C.Net.communityIDv1('5.6.7.8','1.2.3.4',0,0,1)
// '1:crodRHL2FEsHjbv3UkRrfbs4bZ0='

C.Net.isIp()

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Net.isIp(value: string): boolean

Determines whether the value supplied is an IP address (either IPv4 or IPv6).

C.Net.isIpV4()

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Net.isIpV4(value: string): boolean

Determines whether the value supplied is an IPv4 address.

C.Net.isIpV6()

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Net.isIpV6(value: string): boolean

Determines whether the value supplied is an IPv6 address.

C.Net.isIPV4Cidr()

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Net.isIPV4Cidr(value: string): boolean

Determines whether a value supplied is an IPv4 CIDR range.

Returns true if the value is a valid IPv4 CIDR range; otherwise, false.

C.Net.isIPV6Cidr()

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Net.isIPV6Cidr(value: string): boolean

Determine whether a value supplied is an IPv6 CIDR range.

Returns true if the value is a valid IPv6 CIDR range; otherwise, false.

C.Net.isIpV4AllInterfaces()

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Net.isIpV4AllInterfaces(value): boolean

Determines whether the value supplied is the IPv4 all-interfaces address, typically used to bind to all IPv4 interfaces – i.e., ‘0.0.0.0’.

C.Net.isIpV6AllInterfaces()

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Net.isIpV6AllInterfaces(value): boolean

Determines whether the value supplied is an IPv6 all-interfaces address, typically used to bind to all IPv6 interfaces – one of: ‘::’, ‘0:0:0:0:0:0:0:0’, or ‘0000:0000:0000:0000:0000:0000:0000:0000’.

C.Net.ipv6Normalize()

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Net.ipv6Normalize(address: string): string

Normalizes an IPV6 address based on RFC draft-ietf-6man-text-addr-representation-04.

C.Net.isPrivate()

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Net.isPrivate(address: string): boolean

Determines whether the supplied IPv4 address is in the range of private addresses per RFC1918.

C.Net.parseAddressOrRangeString()

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Net.parseAddressOrRangeString(source: string, mask?: string | number)

Parses a string representation of an IP or IP range.

Returns an IPv4 or IPv6 object. When the source argument is an IP range, this method returns the first IP in the range.

C.Net.IPv4_CIDR_REGEX

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Net.IPv4_CIDR_REGEX: RegExp

The regular expressions for matching IP CIDR.