diff options
Diffstat (limited to 'vendor/github.com/docker/libnetwork/ipamutils')
-rw-r--r-- | vendor/github.com/docker/libnetwork/ipamutils/utils.go | 135 |
1 files changed, 135 insertions, 0 deletions
diff --git a/vendor/github.com/docker/libnetwork/ipamutils/utils.go b/vendor/github.com/docker/libnetwork/ipamutils/utils.go new file mode 100644 index 000000000..3fd37cd88 --- /dev/null +++ b/vendor/github.com/docker/libnetwork/ipamutils/utils.go @@ -0,0 +1,135 @@ +// Package ipamutils provides utility functions for ipam management +package ipamutils + +import ( + "fmt" + "net" + "sync" +) + +var ( + // PredefinedLocalScopeDefaultNetworks contains a list of 31 IPv4 private networks with host size 16 and 12 + // (172.17-31.x.x/16, 192.168.x.x/20) which do not overlap with the networks in `PredefinedGlobalScopeDefaultNetworks` + PredefinedLocalScopeDefaultNetworks []*net.IPNet + // PredefinedGlobalScopeDefaultNetworks contains a list of 64K IPv4 private networks with host size 8 + // (10.x.x.x/24) which do not overlap with the networks in `PredefinedLocalScopeDefaultNetworks` + PredefinedGlobalScopeDefaultNetworks []*net.IPNet + mutex sync.Mutex + localScopeDefaultNetworks = []*NetworkToSplit{{"172.17.0.0/16", 16}, {"172.18.0.0/16", 16}, {"172.19.0.0/16", 16}, + {"172.20.0.0/14", 16}, {"172.24.0.0/14", 16}, {"172.28.0.0/14", 16}, + {"192.168.0.0/16", 20}} + globalScopeDefaultNetworks = []*NetworkToSplit{{"10.0.0.0/8", 24}} +) + +// NetworkToSplit represent a network that has to be split in chunks with mask length Size. +// Each subnet in the set is derived from the Base pool. Base is to be passed +// in CIDR format. +// Example: a Base "10.10.0.0/16 with Size 24 will define the set of 256 +// 10.10.[0-255].0/24 address pools +type NetworkToSplit struct { + Base string `json:"base"` + Size int `json:"size"` +} + +func init() { + var err error + if PredefinedGlobalScopeDefaultNetworks, err = splitNetworks(globalScopeDefaultNetworks); err != nil { + //we are going to panic in case of error as we should never get into this state + panic("InitAddressPools failed to initialize the global scope default address pool") + } + + if PredefinedLocalScopeDefaultNetworks, err = splitNetworks(localScopeDefaultNetworks); err != nil { + //we are going to panic in case of error as we should never get into this state + panic("InitAddressPools failed to initialize the local scope default address pool") + } +} + +// configDefaultNetworks configures local as well global default pool based on input +func configDefaultNetworks(defaultAddressPool []*NetworkToSplit, result *[]*net.IPNet) error { + mutex.Lock() + defer mutex.Unlock() + defaultNetworks, err := splitNetworks(defaultAddressPool) + if err != nil { + return err + } + *result = defaultNetworks + return nil +} + +// GetGlobalScopeDefaultNetworks returns PredefinedGlobalScopeDefaultNetworks +func GetGlobalScopeDefaultNetworks() []*net.IPNet { + mutex.Lock() + defer mutex.Unlock() + return PredefinedGlobalScopeDefaultNetworks +} + +// GetLocalScopeDefaultNetworks returns PredefinedLocalScopeDefaultNetworks +func GetLocalScopeDefaultNetworks() []*net.IPNet { + mutex.Lock() + defer mutex.Unlock() + return PredefinedLocalScopeDefaultNetworks +} + +// ConfigGlobalScopeDefaultNetworks configures global default pool. +// Ideally this will be called from SwarmKit as part of swarm init +func ConfigGlobalScopeDefaultNetworks(defaultAddressPool []*NetworkToSplit) error { + if defaultAddressPool == nil { + defaultAddressPool = globalScopeDefaultNetworks + } + return configDefaultNetworks(defaultAddressPool, &PredefinedGlobalScopeDefaultNetworks) +} + +// ConfigLocalScopeDefaultNetworks configures local default pool. +// Ideally this will be called during libnetwork init +func ConfigLocalScopeDefaultNetworks(defaultAddressPool []*NetworkToSplit) error { + if defaultAddressPool == nil { + return nil + } + return configDefaultNetworks(defaultAddressPool, &PredefinedLocalScopeDefaultNetworks) +} + +// splitNetworks takes a slice of networks, split them accordingly and returns them +func splitNetworks(list []*NetworkToSplit) ([]*net.IPNet, error) { + localPools := make([]*net.IPNet, 0, len(list)) + + for _, p := range list { + _, b, err := net.ParseCIDR(p.Base) + if err != nil { + return nil, fmt.Errorf("invalid base pool %q: %v", p.Base, err) + } + ones, _ := b.Mask.Size() + if p.Size <= 0 || p.Size < ones { + return nil, fmt.Errorf("invalid pools size: %d", p.Size) + } + localPools = append(localPools, splitNetwork(p.Size, b)...) + } + return localPools, nil +} + +func splitNetwork(size int, base *net.IPNet) []*net.IPNet { + one, bits := base.Mask.Size() + mask := net.CIDRMask(size, bits) + n := 1 << uint(size-one) + s := uint(bits - size) + list := make([]*net.IPNet, 0, n) + + for i := 0; i < n; i++ { + ip := copyIP(base.IP) + addIntToIP(ip, uint(i<<s)) + list = append(list, &net.IPNet{IP: ip, Mask: mask}) + } + return list +} + +func copyIP(from net.IP) net.IP { + ip := make([]byte, len(from)) + copy(ip, from) + return ip +} + +func addIntToIP(array net.IP, ordinal uint) { + for i := len(array) - 1; i >= 0; i-- { + array[i] |= (byte)(ordinal & 0xff) + ordinal >>= 8 + } +} |