41 lines
910 B
Go
41 lines
910 B
Go
package dhcpv4
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import (
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"net"
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"github.com/u-root/uio/uio"
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)
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// IPMask represents an option encapsulating the subnet mask.
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//
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// This option implements the subnet mask option in RFC 2132, Section 3.3.
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type IPMask net.IPMask
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// ToBytes returns a serialized stream of bytes for this option.
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func (im IPMask) ToBytes() []byte {
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if len(im) > net.IPv4len {
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return im[:net.IPv4len]
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}
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return im
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}
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// String returns a human-readable string.
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func (im IPMask) String() string {
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return net.IPMask(im).String()
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}
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// FromBytes parses im from data per RFC 2132.
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func (im *IPMask) FromBytes(data []byte) error {
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buf := uio.NewBigEndianBuffer(data)
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*im = IPMask(buf.CopyN(net.IPv4len))
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return buf.FinError()
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}
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// OptSubnetMask returns a new DHCPv4 SubnetMask option per RFC 2132, Section 3.3.
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func OptSubnetMask(mask net.IPMask) Option {
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return Option{
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Code: OptionSubnetMask,
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Value: IPMask(mask),
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}
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}
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