libpod: deduplicate ports in db

The OCICNI port format has one big problem: It does not support ranges.
So if a users forwards a range of 1k ports with podman run -p 1001-2000
we have to store each of the thousand ports individually as array element.
This bloats the db and makes the JSON encoding and decoding much slower.
In many places we already use a better port struct type which supports
ranges, e.g. `pkg/specgen` or the new network interface.

Because of this we have to do many runtime conversions between the two
port formats. If everything uses the new format we can skip the runtime
conversions.

This commit adds logic to replace all occurrences of the old format
with the new one. The database will automatically migrate the ports
to new format when the container config is read for the first time
after the update.

The `ParsePortMapping` function is `pkg/specgen/generate` has been
reworked to better work with the new format. The new logic is able
to deduplicate the given ports. This is necessary the ensure we
store them efficiently in the DB. The new code should also be more
performant than the old one.

To prove that the code is fast enough I added go benchmarks. Parsing
1 million ports took less than 0.5 seconds on my laptop.

Benchmark normalize PortMappings in specgen:
Please note that the 1 million ports are actually 20x 50k ranges
because we cannot have bigger ranges than 65535 ports.
```
$ go test -bench=. -benchmem  ./pkg/specgen/generate/
goos: linux
goarch: amd64
pkg: github.com/containers/podman/v3/pkg/specgen/generate
cpu: Intel(R) Core(TM) i7-10850H CPU @ 2.70GHz
BenchmarkParsePortMappingNoPorts-12             480821532                2.230 ns/op           0 B/op          0 allocs/op
BenchmarkParsePortMapping1-12                      38972             30183 ns/op          131584 B/op          9 allocs/op
BenchmarkParsePortMapping100-12                    18752             60688 ns/op          141088 B/op        315 allocs/op
BenchmarkParsePortMapping1k-12                      3104            331719 ns/op          223840 B/op       3018 allocs/op
BenchmarkParsePortMapping10k-12                      376           3122930 ns/op         1223650 B/op      30027 allocs/op
BenchmarkParsePortMapping1m-12                         3         390869926 ns/op        124593840 B/op   4000624 allocs/op
BenchmarkParsePortMappingReverse100-12             18940             63414 ns/op          141088 B/op        315 allocs/op
BenchmarkParsePortMappingReverse1k-12               3015            362500 ns/op          223841 B/op       3018 allocs/op
BenchmarkParsePortMappingReverse10k-12               343           3318135 ns/op         1223650 B/op      30027 allocs/op
BenchmarkParsePortMappingReverse1m-12                  3         403392469 ns/op        124593840 B/op   4000624 allocs/op
BenchmarkParsePortMappingRange1-12                 37635             28756 ns/op          131584 B/op          9 allocs/op
BenchmarkParsePortMappingRange100-12               39604             28935 ns/op          131584 B/op          9 allocs/op
BenchmarkParsePortMappingRange1k-12                38384             29921 ns/op          131584 B/op          9 allocs/op
BenchmarkParsePortMappingRange10k-12               29479             40381 ns/op          131584 B/op          9 allocs/op
BenchmarkParsePortMappingRange1m-12                  927           1279369 ns/op          143022 B/op        164 allocs/op
PASS
ok      github.com/containers/podman/v3/pkg/specgen/generate    25.492s
```

Benchmark convert old port format to new one:
```
go test -bench=. -benchmem  ./libpod/
goos: linux
goarch: amd64
pkg: github.com/containers/podman/v3/libpod
cpu: Intel(R) Core(TM) i7-10850H CPU @ 2.70GHz
Benchmark_ocicniPortsToNetTypesPortsNoPorts-12          663526126                1.663 ns/op           0 B/op          0 allocs/op
Benchmark_ocicniPortsToNetTypesPorts1-12                 7858082               141.9 ns/op            72 B/op          2 allocs/op
Benchmark_ocicniPortsToNetTypesPorts10-12                2065347               571.0 ns/op           536 B/op          4 allocs/op
Benchmark_ocicniPortsToNetTypesPorts100-12                138478              8641 ns/op            4216 B/op          4 allocs/op
Benchmark_ocicniPortsToNetTypesPorts1k-12                   9414            120964 ns/op           41080 B/op          4 allocs/op
Benchmark_ocicniPortsToNetTypesPorts10k-12                   781           1490526 ns/op          401528 B/op          4 allocs/op
Benchmark_ocicniPortsToNetTypesPorts1m-12                      4         250579010 ns/op        40001656 B/op          4 allocs/op
PASS
ok      github.com/containers/podman/v3/libpod  11.727s
```

Signed-off-by: Paul Holzinger <pholzing@redhat.com>

8 files changed, 1491 insertions, 296 deletions

diff --git a/pkg/checkpoint/checkpoint_restore.go b/pkg/checkpoint/checkpoint_restore.go
index f53e31f9b..637f1c0e8 100644
--- a/pkg/checkpoint/checkpoint_restore.go
+++ b/pkg/checkpoint/checkpoint_restore.go
@@ -193,7 +193,7 @@ func CRImportCheckpoint(ctx context.Context, runtime *libpod.Runtime, restoreOpt
 	}
 
 	if len(restoreOptions.PublishPorts) > 0 {
-		ports, _, _, err := generate.ParsePortMapping(restoreOptions.PublishPorts)
+		ports, err := generate.ParsePortMapping(restoreOptions.PublishPorts, nil)
 		if err != nil {
 			return nil, err
 		}
diff --git a/pkg/domain/entities/container_ps.go b/pkg/domain/entities/container_ps.go
index 58f231a2f..d018d373f 100644
--- a/pkg/domain/entities/container_ps.go
+++ b/pkg/domain/entities/container_ps.go
@@ -54,7 +54,7 @@ type ListContainer struct {
 	// boolean to be set
 	PodName string
 	// Port mappings
-	Ports []types.OCICNIPortMapping
+	Ports []types.PortMapping
 	// Size of the container rootfs.  Requires the size boolean to be true
 	Size *define.ContainerSize
 	// Time when container started
diff --git a/pkg/domain/entities/containers.go b/pkg/domain/entities/containers.go
index deae85fe1..869c616ea 100644
--- a/pkg/domain/entities/containers.go
+++ b/pkg/domain/entities/containers.go
@@ -422,7 +422,7 @@ type ContainerPortOptions struct {
 // the CLI to output ports
 type ContainerPortReport struct {
 	Id    string //nolint
-	Ports []nettypes.OCICNIPortMapping
+	Ports []nettypes.PortMapping
 }
 
 // ContainerCpOptions describes input options for cp.
diff --git a/pkg/rootlessport/rootlessport_linux.go b/pkg/rootlessport/rootlessport_linux.go
index 7b9e5bbfa..7e6075789 100644
--- a/pkg/rootlessport/rootlessport_linux.go
+++ b/pkg/rootlessport/rootlessport_linux.go
@@ -23,7 +23,7 @@ const (
 // Config needs to be provided to the process via stdin as a JSON string.
 // stdin needs to be closed after the message has been written.
 type Config struct {
-	Mappings    []types.OCICNIPortMapping
+	Mappings    []types.PortMapping
 	NetNSPath   string
 	ExitFD      int
 	ReadyFD     int
diff --git a/pkg/specgen/generate/pod_create.go b/pkg/specgen/generate/pod_create.go
index 88ebc7ae3..501bce05d 100644
--- a/pkg/specgen/generate/pod_create.go
+++ b/pkg/specgen/generate/pod_create.go
@@ -204,11 +204,11 @@ func createPodOptions(p *specgen.PodSpecGenerator, rt *libpod.Runtime, infraSpec
 // replacing necessary values with those specified in pod creation
 func MapSpec(p *specgen.PodSpecGenerator) (*specgen.SpecGenerator, error) {
 	if len(p.PortMappings) > 0 {
-		ports, _, _, err := ParsePortMapping(p.PortMappings)
+		ports, err := ParsePortMapping(p.PortMappings, nil)
 		if err != nil {
 			return nil, err
 		}
-		p.InfraContainerSpec.PortMappings = libpod.WithInfraContainerPorts(ports, p.InfraContainerSpec)
+		p.InfraContainerSpec.PortMappings = ports
 	}
 	switch p.NetNS.NSMode {
 	case specgen.Default, "":
diff --git a/pkg/specgen/generate/ports.go b/pkg/specgen/generate/ports.go
index 992b4a8e9..53a5e5697 100644
--- a/pkg/specgen/generate/ports.go
+++ b/pkg/specgen/generate/ports.go
@@ -2,7 +2,9 @@ package generate
 
 import (
 	"context"
+	"fmt"
 	"net"
+	"sort"
 	"strconv"
 	"strings"
 
@@ -11,6 +13,7 @@ import (
 	"github.com/containers/podman/v3/utils"
 
 	"github.com/containers/podman/v3/pkg/specgen"
+	"github.com/containers/podman/v3/pkg/util"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 )
@@ -21,252 +24,323 @@ const (
 	protoSCTP = "sctp"
 )
 
-// Parse port maps to OCICNI port mappings.
-// Returns a set of OCICNI port mappings, and maps of utilized container and
+// joinTwoPortsToRangePortIfPossible will expect two ports the previous port one must have a lower or equal hostPort than the current port.
+func joinTwoPortsToRangePortIfPossible(ports *[]types.PortMapping, allHostPorts, allContainerPorts, currentHostPorts *[65536]bool,
+	previousPort *types.PortMapping, port types.PortMapping) (*types.PortMapping, error) {
+	// no previous port just return the current one
+	if previousPort == nil {
+		return &port, nil
+	}
+	if previousPort.HostPort+previousPort.Range >= port.HostPort {
+		// check if the port range matches the host and container ports
+		portDiff := port.HostPort - previousPort.HostPort
+		if portDiff == port.ContainerPort-previousPort.ContainerPort {
+			// calc the new range use the old range and add the difference between the ports
+			newRange := port.Range + portDiff
+			// if the newRange is greater than the old range use it
+			// this is important otherwise we would could lower the range
+			if newRange > previousPort.Range {
+				previousPort.Range = newRange
+			}
+			return previousPort, nil
+		}
+		// if both host port ranges overlap and the container port range did not match
+		// we have to error because we cannot assign the same host port to more than one container port
+		if previousPort.HostPort+previousPort.Range-1 > port.HostPort {
+			return nil, errors.Errorf("conflicting port mappings for host port %d (protocol %s)", port.HostPort, port.Protocol)
+		}
+	}
+	// we could not join the ports so we append the old one to the list
+	// and return the current port as previous port
+	addPortToUsedPorts(ports, allHostPorts, allContainerPorts, currentHostPorts, previousPort)
+	return &port, nil
+}
+
+// joinTwoContainerPortsToRangePortIfPossible will expect two ports with both no host port set,
+//  the previous port one must have a lower or equal containerPort than the current port.
+func joinTwoContainerPortsToRangePortIfPossible(ports *[]types.PortMapping, allHostPorts, allContainerPorts, currentHostPorts *[65536]bool,
+	previousPort *types.PortMapping, port types.PortMapping) (*types.PortMapping, error) {
+	// no previous port just return the current one
+	if previousPort == nil {
+		return &port, nil
+	}
+	if previousPort.ContainerPort+previousPort.Range > port.ContainerPort {
+		// calc the new range use the old range and add the difference between the ports
+		newRange := port.ContainerPort - previousPort.ContainerPort + port.Range
+		// if the newRange is greater than the old range use it
+		// this is important otherwise we would could lower the range
+		if newRange > previousPort.Range {
+			previousPort.Range = newRange
+		}
+		return previousPort, nil
+	}
+	// we could not join the ports so we append the old one to the list
+	// and return the current port as previous port
+	newPort, err := getRandomHostPort(currentHostPorts, *previousPort)
+	if err != nil {
+		return nil, err
+	}
+	addPortToUsedPorts(ports, allHostPorts, allContainerPorts, currentHostPorts, &newPort)
+	return &port, nil
+}
+
+func addPortToUsedPorts(ports *[]types.PortMapping, allHostPorts, allContainerPorts, currentHostPorts *[65536]bool, port *types.PortMapping) {
+	for i := uint16(0); i < port.Range; i++ {
+		h := port.HostPort + i
+		allHostPorts[h] = true
+		currentHostPorts[h] = true
+		c := port.ContainerPort + i
+		allContainerPorts[c] = true
+	}
+	*ports = append(*ports, *port)
+}
+
+// getRandomHostPort get a random host port mapping for the given port
+// the caller has to supply a array with  he already used ports
+func getRandomHostPort(hostPorts *[65536]bool, port types.PortMapping) (types.PortMapping, error) {
+outer:
+	for i := 0; i < 15; i++ {
+		ranPort, err := utils.GetRandomPort()
+		if err != nil {
+			return port, err
+		}
+
+		// if port range is exceeds max port we cannot use it
+		if ranPort+int(port.Range) > 65535 {
+			continue
+		}
+
+		// check if there is a port in the range which is used
+		for j := 0; j < int(port.Range); j++ {
+			// port already used
+			if hostPorts[ranPort+j] {
+				continue outer
+			}
+		}
+
+		port.HostPort = uint16(ranPort)
+		return port, nil
+	}
+
+	// add range to error message if needed
+	rangePort := ""
+	if port.Range > 1 {
+		rangePort = fmt.Sprintf("with range %d ", port.Range)
+	}
+
+	return port, errors.Errorf("failed to find an open port to expose container port %d %son the host", port.ContainerPort, rangePort)
+}
+
+// Parse port maps to port mappings.
+// Returns a set of port mappings, and maps of utilized container and
 // host ports.
-func ParsePortMapping(portMappings []types.PortMapping) ([]types.OCICNIPortMapping, map[string]map[string]map[uint16]uint16, map[string]map[string]map[uint16]uint16, error) {
-	// First, we need to validate the ports passed in the specgen, and then
-	// convert them into CNI port mappings.
-	type tempMapping struct {
-		mapping      types.OCICNIPortMapping
-		startOfRange bool
-		isInRange    bool
+func ParsePortMapping(portMappings []types.PortMapping, exposePorts map[uint16][]string) ([]types.PortMapping, error) {
+	if len(portMappings) == 0 && len(exposePorts) == 0 {
+		return nil, nil
 	}
-	tempMappings := []tempMapping{}
-
-	// To validate, we need two maps: one for host ports, one for container
-	// ports.
-	// Each is a map of protocol to map of IP address to map of port to
-	// port (for hostPortValidate, it's host port to container port;
-	// for containerPortValidate, container port to host port.
-	// These will ensure no collisions.
-	hostPortValidate := make(map[string]map[string]map[uint16]uint16)
-	containerPortValidate := make(map[string]map[string]map[uint16]uint16)
-
-	// Initialize the first level of maps (we can't really guess keys for
-	// the rest).
-	for _, proto := range []string{protoTCP, protoUDP, protoSCTP} {
-		hostPortValidate[proto] = make(map[string]map[uint16]uint16)
-		containerPortValidate[proto] = make(map[string]map[uint16]uint16)
+
+	// tempMapping stores the ports without ip and protocol
+	type tempMapping struct {
+		hostPort      uint16
+		containerPort uint16
+		rangePort     uint16
 	}
 
-	postAssignHostPort := false
+	// portMap is a temporary structure to sort all ports
+	// the map is hostIp -> protocol -> array of mappings
+	portMap := make(map[string]map[string][]tempMapping)
+
+	// allUsedContainerPorts stores all used ports for each protocol
+	// the key is the protocol and the array is 65536 elements long for each port.
+	allUsedContainerPortsMap := make(map[string][65536]bool)
+	allUsedHostPortsMap := make(map[string][65536]bool)
 
-	// Iterate through all port mappings, generating OCICNI PortMapping
-	// structs and validating there is no overlap.
+	// First, we need to validate the ports passed in the specgen
 	for _, port := range portMappings {
 		// First, check proto
 		protocols, err := checkProtocol(port.Protocol, true)
 		if err != nil {
-			return nil, nil, nil, err
-		}
-
-		// Validate host IP
-		hostIP := port.HostIP
-		if hostIP == "" {
-			hostIP = "0.0.0.0"
+			return nil, err
 		}
-		if ip := net.ParseIP(hostIP); ip == nil {
-			return nil, nil, nil, errors.Errorf("invalid IP address %s in port mapping", port.HostIP)
+		if port.HostIP != "" {
+			if ip := net.ParseIP(port.HostIP); ip == nil {
+				return nil, errors.Errorf("invalid IP address %q in port mapping", port.HostIP)
+			}
 		}
 
 		// Validate port numbers and range.
-		len := port.Range
-		if len == 0 {
-			len = 1
+		portRange := port.Range
+		if portRange == 0 {
+			portRange = 1
 		}
 		containerPort := port.ContainerPort
 		if containerPort == 0 {
-			return nil, nil, nil, errors.Errorf("container port number must be non-0")
+			return nil, errors.Errorf("container port number must be non-0")
 		}
 		hostPort := port.HostPort
-		if uint32(len-1)+uint32(containerPort) > 65535 {
-			return nil, nil, nil, errors.Errorf("container port range exceeds maximum allowable port number")
+		if uint32(portRange-1)+uint32(containerPort) > 65535 {
+			return nil, errors.Errorf("container port range exceeds maximum allowable port number")
 		}
-		if uint32(len-1)+uint32(hostPort) > 65536 {
-			return nil, nil, nil, errors.Errorf("host port range exceeds maximum allowable port number")
+		if uint32(portRange-1)+uint32(hostPort) > 65535 {
+			return nil, errors.Errorf("host port range exceeds maximum allowable port number")
 		}
 
-		// Iterate through ports, populating maps to check for conflicts
-		// and generating CNI port mappings.
-		for _, p := range protocols {
-			hostIPMap := hostPortValidate[p]
-			ctrIPMap := containerPortValidate[p]
-
-			hostPortMap, ok := hostIPMap[hostIP]
-			if !ok {
-				hostPortMap = make(map[uint16]uint16)
-				hostIPMap[hostIP] = hostPortMap
+		hostProtoMap, ok := portMap[port.HostIP]
+		if !ok {
+			hostProtoMap = make(map[string][]tempMapping)
+			for _, proto := range []string{protoTCP, protoUDP, protoSCTP} {
+				hostProtoMap[proto] = make([]tempMapping, 0)
 			}
-			ctrPortMap, ok := ctrIPMap[hostIP]
-			if !ok {
-				ctrPortMap = make(map[uint16]uint16)
-				ctrIPMap[hostIP] = ctrPortMap
-			}
-
-			// Iterate through all port numbers in the requested
-			// range.
-			var index uint16
-			for index = 0; index < len; index++ {
-				cPort := containerPort + index
-				hPort := hostPort
-				// Only increment host port if it's not 0.
-				if hostPort != 0 {
-					hPort += index
-				}
-
-				if cPort == 0 {
-					return nil, nil, nil, errors.Errorf("container port cannot be 0")
-				}
+			portMap[port.HostIP] = hostProtoMap
+		}
 
-				// Host port is allowed to be 0. If it is, we
-				// select a random port on the host.
-				// This will happen *after* all other ports are
-				// placed, to ensure we don't accidentally
-				// select a port that a later mapping wanted.
-				if hPort == 0 {
-					// If we already have a host port
-					// assigned to their container port -
-					// just use that.
-					if ctrPortMap[cPort] != 0 {
-						hPort = ctrPortMap[cPort]
-					} else {
-						postAssignHostPort = true
-					}
-				} else {
-					testHPort := hostPortMap[hPort]
-					if testHPort != 0 && testHPort != cPort {
-						return nil, nil, nil, errors.Errorf("conflicting port mappings for host port %d (protocol %s)", hPort, p)
-					}
-					hostPortMap[hPort] = cPort
-
-					// Mapping a container port to multiple
-					// host ports is allowed.
-					// We only store the latest of these in
-					// the container port map - we don't
-					// need to know all of them, just one.
-					testCPort := ctrPortMap[cPort]
-					ctrPortMap[cPort] = hPort
-
-					// If we have an exact duplicate, just continue
-					if testCPort == hPort && testHPort == cPort {
-						continue
-					}
-				}
+		p := tempMapping{
+			hostPort:      port.HostPort,
+			containerPort: port.ContainerPort,
+			rangePort:     portRange,
+		}
 
-				// We appear to be clear. Make an OCICNI port
-				// struct.
-				// Don't use hostIP - we want to preserve the
-				// empty string hostIP by default for compat.
-				cniPort := types.OCICNIPortMapping{
-					HostPort:      int32(hPort),
-					ContainerPort: int32(cPort),
-					Protocol:      p,
-					HostIP:        port.HostIP,
-				}
-				tempMappings = append(
-					tempMappings,
-					tempMapping{
-						mapping:      cniPort,
-						startOfRange: port.Range > 1 && index == 0,
-						isInRange:    port.Range > 1,
-					},
-				)
-			}
+		for _, proto := range protocols {
+			hostProtoMap[proto] = append(hostProtoMap[proto], p)
 		}
 	}
 
-	// Handle any 0 host ports now by setting random container ports.
-	if postAssignHostPort {
-		remadeMappings := make([]types.OCICNIPortMapping, 0, len(tempMappings))
-
-		var (
-			candidate int
-			err       error
-		)
-
-		// Iterate over all
-		for _, tmp := range tempMappings {
-			p := tmp.mapping
+	// we do no longer need the original port mappings
+	// set it to 0 length so we can resuse it to populate
+	// the slice again while keeping the underlying capacity
+	portMappings = portMappings[:0]
 
-			if p.HostPort != 0 {
-				remadeMappings = append(remadeMappings, p)
+	for hostIP, protoMap := range portMap {
+		for protocol, ports := range protoMap {
+			ports := ports
+			if len(ports) == 0 {
 				continue
 			}
-
-			hostIPMap := hostPortValidate[p.Protocol]
-			ctrIPMap := containerPortValidate[p.Protocol]
-
-			hostPortMap, ok := hostIPMap[p.HostIP]
-			if !ok {
-				hostPortMap = make(map[uint16]uint16)
-				hostIPMap[p.HostIP] = hostPortMap
+			// 1. sort the ports by host port
+			// use a small hack to make sure ports with host port 0 are sorted last
+			sort.Slice(ports, func(i, j int) bool {
+				if ports[i].hostPort == ports[j].hostPort {
+					return ports[i].containerPort < ports[j].containerPort
+				}
+				if ports[i].hostPort == 0 {
+					return false
+				}
+				if ports[j].hostPort == 0 {
+					return true
+				}
+				return ports[i].hostPort < ports[j].hostPort
+			})
+
+			allUsedContainerPorts := allUsedContainerPortsMap[protocol]
+			allUsedHostPorts := allUsedHostPortsMap[protocol]
+			var usedHostPorts [65536]bool
+
+			var previousPort *types.PortMapping
+			var i int
+			for i = 0; i < len(ports); i++ {
+				if ports[i].hostPort == 0 {
+					// because the ports are sorted and host port 0 is last
+					// we can break when we hit 0
+					// we will fit them in afterwards
+					break
+				}
+				p := types.PortMapping{
+					HostIP:        hostIP,
+					Protocol:      protocol,
+					HostPort:      ports[i].hostPort,
+					ContainerPort: ports[i].containerPort,
+					Range:         ports[i].rangePort,
+				}
+				var err error
+				previousPort, err = joinTwoPortsToRangePortIfPossible(&portMappings, &allUsedHostPorts,
+					&allUsedContainerPorts, &usedHostPorts, previousPort, p)
+				if err != nil {
+					return nil, err
+				}
 			}
-			ctrPortMap, ok := ctrIPMap[p.HostIP]
-			if !ok {
-				ctrPortMap = make(map[uint16]uint16)
-				ctrIPMap[p.HostIP] = ctrPortMap
+			if previousPort != nil {
+				addPortToUsedPorts(&portMappings, &allUsedHostPorts,
+					&allUsedContainerPorts, &usedHostPorts, previousPort)
 			}
 
-			// See if container port has been used elsewhere
-			if ctrPortMap[uint16(p.ContainerPort)] != 0 {
-				// Duplicate definition. Let's not bother
-				// including it.
-				continue
+			// now take care of the hostPort = 0 ports
+			previousPort = nil
+			for i < len(ports) {
+				p := types.PortMapping{
+					HostIP:        hostIP,
+					Protocol:      protocol,
+					ContainerPort: ports[i].containerPort,
+					Range:         ports[i].rangePort,
+				}
+				var err error
+				previousPort, err = joinTwoContainerPortsToRangePortIfPossible(&portMappings, &allUsedHostPorts,
+					&allUsedContainerPorts, &usedHostPorts, previousPort, p)
+				if err != nil {
+					return nil, err
+				}
+				i++
+			}
+			if previousPort != nil {
+				newPort, err := getRandomHostPort(&usedHostPorts, *previousPort)
+				if err != nil {
+					return nil, err
+				}
+				addPortToUsedPorts(&portMappings, &allUsedHostPorts,
+					&allUsedContainerPorts, &usedHostPorts, &newPort)
 			}
 
-			// Max retries to ensure we don't loop forever.
-			for i := 0; i < 15; i++ {
-				// Only get a random candidate for single entries or the start
-				// of a range. Otherwise we just increment the candidate.
-				if !tmp.isInRange || tmp.startOfRange {
-					candidate, err = utils.GetRandomPort()
+			allUsedContainerPortsMap[protocol] = allUsedContainerPorts
+			allUsedHostPortsMap[protocol] = allUsedHostPorts
+		}
+	}
+
+	if len(exposePorts) > 0 {
+		logrus.Debugf("Adding exposed ports")
+
+		for port, protocols := range exposePorts {
+			newProtocols := make([]string, 0, len(protocols))
+			for _, protocol := range protocols {
+				if !allUsedContainerPortsMap[protocol][port] {
+					p := types.PortMapping{
+						ContainerPort: port,
+						Protocol:      protocol,
+						Range:         1,
+					}
+					allPorts := allUsedContainerPortsMap[protocol]
+					p, err := getRandomHostPort(&allPorts, p)
 					if err != nil {
-						return nil, nil, nil, errors.Wrapf(err, "error getting candidate host port for container port %d", p.ContainerPort)
+						return nil, err
 					}
+					portMappings = append(portMappings, p)
 				} else {
-					candidate++
-				}
-
-				if hostPortMap[uint16(candidate)] == 0 {
-					logrus.Debugf("Successfully assigned container port %d to host port %d (IP %s Protocol %s)", p.ContainerPort, candidate, p.HostIP, p.Protocol)
-					hostPortMap[uint16(candidate)] = uint16(p.ContainerPort)
-					ctrPortMap[uint16(p.ContainerPort)] = uint16(candidate)
-					p.HostPort = int32(candidate)
-					break
+					newProtocols = append(newProtocols, protocol)
 				}
 			}
-			if p.HostPort == 0 {
-				return nil, nil, nil, errors.Errorf("could not find open host port to map container port %d to", p.ContainerPort)
+			// make sure to delete the key from the map if there are no protocols left
+			if len(newProtocols) == 0 {
+				delete(exposePorts, port)
+			} else {
+				exposePorts[port] = newProtocols
 			}
-			remadeMappings = append(remadeMappings, p)
 		}
-		return remadeMappings, containerPortValidate, hostPortValidate, nil
 	}
+	return portMappings, nil
+}
 
-	finalMappings := []types.OCICNIPortMapping{}
-	for _, m := range tempMappings {
-		finalMappings = append(finalMappings, m.mapping)
+func appendProtocolsNoDuplicates(slice []string, protocols []string) []string {
+	for _, proto := range protocols {
+		if util.StringInSlice(proto, slice) {
+			continue
+		}
+		slice = append(slice, proto)
 	}
-
-	return finalMappings, containerPortValidate, hostPortValidate, nil
+	return slice
 }
 
 // Make final port mappings for the container
-func createPortMappings(ctx context.Context, s *specgen.SpecGenerator, imageData *libimage.ImageData) ([]types.OCICNIPortMapping, map[uint16][]string, error) {
-	finalMappings, containerPortValidate, hostPortValidate, err := ParsePortMapping(s.PortMappings)
-	if err != nil {
-		return nil, nil, err
-	}
-
-	// No exposed ports so return the port mappings we've made so far.
-	if len(s.Expose) == 0 && imageData == nil {
-		return finalMappings, nil, nil
-	}
-
-	logrus.Debugf("Adding exposed ports")
-
+func createPortMappings(ctx context.Context, s *specgen.SpecGenerator, imageData *libimage.ImageData) ([]types.PortMapping, map[uint16][]string, error) {
 	expose := make(map[uint16]string)
+	var err error
 	if imageData != nil {
 		expose, err = GenExposedPorts(imageData.Config.ExposedPorts)
 		if err != nil {
@@ -274,103 +348,30 @@ func createPortMappings(ctx context.Context, s *specgen.SpecGenerator, imageData
 		}
 	}
 
-	// We need to merge s.Expose into image exposed ports
-	for k, v := range s.Expose {
-		expose[k] = v
-	}
-	// There's been a request to expose some ports. Let's do that.
-	// Start by figuring out what needs to be exposed.
-	// This is a map of container port number to protocols to expose.
-	toExpose := make(map[uint16][]string)
-	for port, proto := range expose {
-		// Validate protocol first
-		protocols, err := checkProtocol(proto, false)
-		if err != nil {
-			return nil, nil, errors.Wrapf(err, "error validating protocols for exposed port %d", port)
-		}
-
-		if port == 0 {
-			return nil, nil, errors.Errorf("cannot expose 0 as it is not a valid port number")
-		}
-
-		// Check to see if the port is already present in existing
-		// mappings.
-		for _, p := range protocols {
-			ctrPortMap, ok := containerPortValidate[p]["0.0.0.0"]
-			if !ok {
-				ctrPortMap = make(map[uint16]uint16)
-				containerPortValidate[p]["0.0.0.0"] = ctrPortMap
+	toExpose := make(map[uint16][]string, len(s.Expose)+len(expose))
+	for _, expose := range []map[uint16]string{expose, s.Expose} {
+		for port, proto := range expose {
+			if port == 0 {
+				return nil, nil, errors.Errorf("cannot expose 0 as it is not a valid port number")
 			}
-
-			if portNum := ctrPortMap[port]; portNum == 0 {
-				// We want to expose this port for this protocol
-				exposeProto, ok := toExpose[port]
-				if !ok {
-					exposeProto = []string{}
-				}
-				exposeProto = append(exposeProto, p)
-				toExpose[port] = exposeProto
+			protocols, err := checkProtocol(proto, false)
+			if err != nil {
+				return nil, nil, errors.Wrapf(err, "error validating protocols for exposed port %d", port)
 			}
+			toExpose[port] = appendProtocolsNoDuplicates(toExpose[port], protocols)
 		}
 	}
 
-	// If not publishing exposed ports return mappings and exposed ports.
+	publishPorts := toExpose
 	if !s.PublishExposedPorts {
-		return finalMappings, toExpose, nil
+		publishPorts = nil
 	}
 
-	// We now have a final list of ports that we want exposed.
-	// Let's find empty, unallocated host ports for them.
-	for port, protocols := range toExpose {
-		for _, p := range protocols {
-			// Find an open port on the host.
-			// I see a faint possibility that this will infinite
-			// loop trying to find a valid open port, so I've
-			// included a max-tries counter.
-			hostPort := 0
-			tries := 15
-			for hostPort == 0 && tries > 0 {
-				// We can't select a specific protocol, which is
-				// unfortunate for the UDP case.
-				candidate, err := utils.GetRandomPort()
-				if err != nil {
-					return nil, nil, err
-				}
-
-				// Check if the host port is already bound
-				hostPortMap, ok := hostPortValidate[p]["0.0.0.0"]
-				if !ok {
-					hostPortMap = make(map[uint16]uint16)
-					hostPortValidate[p]["0.0.0.0"] = hostPortMap
-				}
-
-				if checkPort := hostPortMap[uint16(candidate)]; checkPort != 0 {
-					// Host port is already allocated, try again
-					tries--
-					continue
-				}
-
-				hostPortMap[uint16(candidate)] = port
-				hostPort = candidate
-				logrus.Debugf("Mapping exposed port %d/%s to host port %d", port, p, hostPort)
-
-				// Make a CNI port mapping
-				cniPort := types.OCICNIPortMapping{
-					HostPort:      int32(candidate),
-					ContainerPort: int32(port),
-					Protocol:      p,
-					HostIP:        "",
-				}
-				finalMappings = append(finalMappings, cniPort)
-			}
-			if tries == 0 && hostPort == 0 {
-				// We failed to find an open port.
-				return nil, nil, errors.Errorf("failed to find an open port to expose container port %d on the host", port)
-			}
-		}
+	finalMappings, err := ParsePortMapping(s.PortMappings, publishPorts)
+	if err != nil {
+		return nil, nil, err
 	}
-
-	return finalMappings, nil, nil
+	return finalMappings, toExpose, nil
 }
 
 // Check a string to ensure it is a comma-separated set of valid protocols
@@ -409,7 +410,7 @@ func checkProtocol(protocol string, allowSCTP bool) ([]string, error) {
 }
 
 func GenExposedPorts(exposedPorts map[string]struct{}) (map[uint16]string, error) {
-	expose := make(map[uint16]string)
+	expose := make(map[uint16]string, len(exposedPorts))
 	for imgExpose := range exposedPorts {
 		// Expose format is portNumber[/protocol]
 		splitExpose := strings.SplitN(imgExpose, "/", 2)
@@ -420,12 +421,20 @@ func GenExposedPorts(exposedPorts map[string]struct{}) (map[uint16]string, error
 		if num > 65535 || num < 1 {
 			return nil, errors.Errorf("%d from image EXPOSE statement %q is not a valid port number", num, imgExpose)
 		}
-		// No need to validate protocol, we'll do it below.
-		if len(splitExpose) == 1 {
-			expose[uint16(num)] = "tcp"
+
+		// No need to validate protocol, we'll do it later.
+		newProto := "tcp"
+		if len(splitExpose) == 2 {
+			newProto = splitExpose[1]
+		}
+
+		proto := expose[uint16(num)]
+		if len(proto) > 1 {
+			proto = proto + "," + newProto
 		} else {
-			expose[uint16(num)] = splitExpose[1]
+			proto = newProto
 		}
+		expose[uint16(num)] = proto
 	}
 	return expose, nil
 }
diff --git a/pkg/specgen/generate/ports_bench_test.go b/pkg/specgen/generate/ports_bench_test.go
new file mode 100644
index 000000000..06f02acda
--- /dev/null
+++ b/pkg/specgen/generate/ports_bench_test.go
@@ -0,0 +1,197 @@
+package generate
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/containers/podman/v3/libpod/network/types"
+)
+
+func benchmarkParsePortMapping(b *testing.B, ports []types.PortMapping) {
+	for n := 0; n < b.N; n++ {
+		ParsePortMapping(ports, nil)
+	}
+}
+
+func BenchmarkParsePortMappingNoPorts(b *testing.B) {
+	benchmarkParsePortMapping(b, nil)
+}
+
+func BenchmarkParsePortMapping1(b *testing.B) {
+	benchmarkParsePortMapping(b, []types.PortMapping{
+		{
+			HostPort:      8080,
+			ContainerPort: 80,
+			Protocol:      "tcp",
+		},
+	})
+}
+
+func BenchmarkParsePortMapping100(b *testing.B) {
+	ports := make([]types.PortMapping, 0, 100)
+	for i := uint16(8080); i < 8180; i++ {
+		ports = append(ports, types.PortMapping{
+			HostPort:      i,
+			ContainerPort: i,
+			Protocol:      "tcp",
+		})
+	}
+	b.ResetTimer()
+	benchmarkParsePortMapping(b, ports)
+}
+
+func BenchmarkParsePortMapping1k(b *testing.B) {
+	ports := make([]types.PortMapping, 0, 1000)
+	for i := uint16(8080); i < 9080; i++ {
+		ports = append(ports, types.PortMapping{
+			HostPort:      i,
+			ContainerPort: i,
+			Protocol:      "tcp",
+		})
+	}
+	b.ResetTimer()
+	benchmarkParsePortMapping(b, ports)
+}
+
+func BenchmarkParsePortMapping10k(b *testing.B) {
+	ports := make([]types.PortMapping, 0, 30000)
+	for i := uint16(8080); i < 18080; i++ {
+		ports = append(ports, types.PortMapping{
+			HostPort:      i,
+			ContainerPort: i,
+			Protocol:      "tcp",
+		})
+	}
+	b.ResetTimer()
+	benchmarkParsePortMapping(b, ports)
+}
+
+func BenchmarkParsePortMapping1m(b *testing.B) {
+	ports := make([]types.PortMapping, 0, 1000000)
+	for j := 0; j < 20; j++ {
+		for i := uint16(1); i <= 50000; i++ {
+			ports = append(ports, types.PortMapping{
+				HostPort:      i,
+				ContainerPort: i,
+				Protocol:      "tcp",
+				HostIP:        fmt.Sprintf("192.168.1.%d", j),
+			})
+		}
+	}
+	b.ResetTimer()
+	benchmarkParsePortMapping(b, ports)
+}
+
+func BenchmarkParsePortMappingReverse100(b *testing.B) {
+	ports := make([]types.PortMapping, 0, 100)
+	for i := uint16(8180); i > 8080; i-- {
+		ports = append(ports, types.PortMapping{
+			HostPort:      i,
+			ContainerPort: i,
+			Protocol:      "tcp",
+		})
+	}
+	b.ResetTimer()
+	benchmarkParsePortMapping(b, ports)
+}
+
+func BenchmarkParsePortMappingReverse1k(b *testing.B) {
+	ports := make([]types.PortMapping, 0, 1000)
+	for i := uint16(9080); i > 8080; i-- {
+		ports = append(ports, types.PortMapping{
+			HostPort:      i,
+			ContainerPort: i,
+			Protocol:      "tcp",
+		})
+	}
+	b.ResetTimer()
+	benchmarkParsePortMapping(b, ports)
+}
+
+func BenchmarkParsePortMappingReverse10k(b *testing.B) {
+	ports := make([]types.PortMapping, 0, 30000)
+	for i := uint16(18080); i > 8080; i-- {
+		ports = append(ports, types.PortMapping{
+			HostPort:      i,
+			ContainerPort: i,
+			Protocol:      "tcp",
+		})
+	}
+	b.ResetTimer()
+	benchmarkParsePortMapping(b, ports)
+}
+
+func BenchmarkParsePortMappingReverse1m(b *testing.B) {
+	ports := make([]types.PortMapping, 0, 1000000)
+	for j := 0; j < 20; j++ {
+		for i := uint16(50000); i > 0; i-- {
+			ports = append(ports, types.PortMapping{
+				HostPort:      i,
+				ContainerPort: i,
+				Protocol:      "tcp",
+				HostIP:        fmt.Sprintf("192.168.1.%d", j),
+			})
+		}
+	}
+	b.ResetTimer()
+	benchmarkParsePortMapping(b, ports)
+}
+
+func BenchmarkParsePortMappingRange1(b *testing.B) {
+	benchmarkParsePortMapping(b, []types.PortMapping{
+		{
+			HostPort:      8080,
+			ContainerPort: 80,
+			Protocol:      "tcp",
+			Range:         1,
+		},
+	})
+}
+
+func BenchmarkParsePortMappingRange100(b *testing.B) {
+	benchmarkParsePortMapping(b, []types.PortMapping{
+		{
+			HostPort:      8080,
+			ContainerPort: 80,
+			Protocol:      "tcp",
+			Range:         100,
+		},
+	})
+}
+
+func BenchmarkParsePortMappingRange1k(b *testing.B) {
+	benchmarkParsePortMapping(b, []types.PortMapping{
+		{
+			HostPort:      8080,
+			ContainerPort: 80,
+			Protocol:      "tcp",
+			Range:         1000,
+		},
+	})
+}
+
+func BenchmarkParsePortMappingRange10k(b *testing.B) {
+	benchmarkParsePortMapping(b, []types.PortMapping{
+		{
+			HostPort:      8080,
+			ContainerPort: 80,
+			Protocol:      "tcp",
+			Range:         10000,
+		},
+	})
+}
+
+func BenchmarkParsePortMappingRange1m(b *testing.B) {
+	ports := make([]types.PortMapping, 0, 1000000)
+	for j := 0; j < 20; j++ {
+		ports = append(ports, types.PortMapping{
+			HostPort:      1,
+			ContainerPort: 1,
+			Protocol:      "tcp",
+			Range:         50000,
+			HostIP:        fmt.Sprintf("192.168.1.%d", j),
+		})
+	}
+	b.ResetTimer()
+	benchmarkParsePortMapping(b, ports)
+}
diff --git a/pkg/specgen/generate/ports_test.go b/pkg/specgen/generate/ports_test.go
new file mode 100644
index 000000000..20d5d0166
--- /dev/null
+++ b/pkg/specgen/generate/ports_test.go
@@ -0,0 +1,989 @@
+package generate
+
+import (
+	"testing"
+
+	"github.com/containers/podman/v3/libpod/network/types"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestParsePortMappingWithHostPort(t *testing.T) {
+	tests := []struct {
+		name string
+		arg  []types.PortMapping
+		arg2 map[uint16][]string
+		want []types.PortMapping
+	}{
+		{
+			name: "no ports",
+			arg:  nil,
+			want: nil,
+		},
+		{
+			name: "one tcp port",
+			arg: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+				},
+			},
+			want: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         1,
+				},
+			},
+		},
+		{
+			name: "one tcp port no proto",
+			arg: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+				},
+			},
+			want: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         1,
+				},
+			},
+		},
+		{
+			name: "one udp port",
+			arg: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "udp",
+				},
+			},
+			want: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "udp",
+					Range:         1,
+				},
+			},
+		},
+		{
+			name: "one sctp port",
+			arg: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "sctp",
+				},
+			},
+			want: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "sctp",
+					Range:         1,
+				},
+			},
+		},
+		{
+			name: "one port two protocols",
+			arg: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "tcp,udp",
+				},
+			},
+			want: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         1,
+				},
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "udp",
+					Range:         1,
+				},
+			},
+		},
+		{
+			name: "one port three protocols",
+			arg: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "tcp,udp,sctp",
+				},
+			},
+			want: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         1,
+				},
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "udp",
+					Range:         1,
+				},
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "sctp",
+					Range:         1,
+				},
+			},
+		},
+		{
+			name: "one port with range 1",
+			arg: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         1,
+				},
+			},
+			want: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         1,
+				},
+			},
+		},
+		{
+			name: "one port with range 5",
+			arg: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         5,
+				},
+			},
+			want: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         5,
+				},
+			},
+		},
+		{
+			name: "two ports joined",
+			arg: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+				},
+				{
+					HostPort:      8081,
+					ContainerPort: 81,
+					Protocol:      "tcp",
+				},
+			},
+			want: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         2,
+				},
+			},
+		},
+		{
+			name: "two ports joined with range",
+			arg: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         2,
+				},
+				{
+					HostPort:      8081,
+					ContainerPort: 81,
+					Protocol:      "tcp",
+				},
+			},
+			want: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         2,
+				},
+			},
+		},
+		{
+			name: "two ports with no overlapping range",
+			arg: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         10,
+				},
+				{
+					HostPort:      9090,
+					ContainerPort: 9090,
+					Protocol:      "tcp",
+				},
+			},
+			want: []types.PortMapping{
+				{
+					HostPort:      9090,
+					ContainerPort: 9090,
+					Protocol:      "tcp",
+					Range:         1,
+				},
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         10,
+				},
+			},
+		},
+		{
+			name: "four ports with two overlapping ranges",
+			arg: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         10,
+				},
+				{
+					HostPort:      8085,
+					ContainerPort: 85,
+					Protocol:      "tcp",
+					Range:         10,
+				},
+				{
+					HostPort:      100,
+					ContainerPort: 5,
+					Protocol:      "tcp",
+				},
+				{
+					HostPort:      101,
+					ContainerPort: 6,
+					Protocol:      "tcp",
+				},
+			},
+			want: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         15,
+				},
+				{
+					HostPort:      100,
+					ContainerPort: 5,
+					Protocol:      "tcp",
+					Range:         2,
+				},
+			},
+		},
+		{
+			name: "two overlapping ranges",
+			arg: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         10,
+				},
+				{
+					HostPort:      8085,
+					ContainerPort: 85,
+					Protocol:      "tcp",
+					Range:         2,
+				},
+			},
+			want: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         10,
+				},
+			},
+		},
+		{
+			name: "four overlapping ranges",
+			arg: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         10,
+				},
+				{
+					HostPort:      8085,
+					ContainerPort: 85,
+					Protocol:      "tcp",
+					Range:         2,
+				},
+				{
+					HostPort:      8090,
+					ContainerPort: 90,
+					Protocol:      "tcp",
+					Range:         7,
+				},
+				{
+					HostPort:      8095,
+					ContainerPort: 95,
+					Protocol:      "tcp",
+				},
+			},
+			want: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         17,
+				},
+			},
+		},
+		{
+			name: "one port range overlaps 5 ports",
+			arg: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Range:         20,
+				},
+				{
+					HostPort:      8085,
+					ContainerPort: 85,
+					Range:         2,
+				},
+				{
+					HostPort:      8090,
+					ContainerPort: 90,
+				},
+				{
+					HostPort:      8095,
+					ContainerPort: 95,
+				},
+				{
+					HostPort:      8096,
+					ContainerPort: 96,
+				},
+			},
+			want: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         20,
+				},
+			},
+		},
+		{
+			name: "different host ip same port",
+			arg: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					HostIP:        "192.168.1.1",
+				},
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					HostIP:        "192.168.2.1",
+				},
+			},
+			want: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					HostIP:        "192.168.1.1",
+					Range:         1,
+				},
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					HostIP:        "192.168.2.1",
+					Range:         1,
+				},
+			},
+		},
+	}
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := ParsePortMapping(tt.arg, tt.arg2)
+			assert.NoError(t, err, "error is not nil")
+			// use ElementsMatch instead of Equal because the order is not consistent
+			assert.ElementsMatch(t, tt.want, got, "got unexpected port mapping")
+		})
+	}
+}
+
+func TestParsePortMappingWithoutHostPort(t *testing.T) {
+	tests := []struct {
+		name string
+		arg  []types.PortMapping
+		arg2 map[uint16][]string
+		want []types.PortMapping
+	}{
+		{
+			name: "one tcp port",
+			arg: []types.PortMapping{
+				{
+					HostPort:      0,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+				},
+			},
+			want: []types.PortMapping{
+				{
+					HostPort:      0,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         1,
+				},
+			},
+		},
+		{
+			name: "one port with two protocols",
+			arg: []types.PortMapping{
+				{
+					HostPort:      0,
+					ContainerPort: 80,
+					Protocol:      "tcp,udp",
+				},
+			},
+			want: []types.PortMapping{
+				{
+					HostPort:      0,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         1,
+				},
+				{
+					HostPort:      0,
+					ContainerPort: 80,
+					Protocol:      "udp",
+					Range:         1,
+				},
+			},
+		},
+		{
+			name: "same port twice",
+			arg: []types.PortMapping{
+				{
+					HostPort:      0,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+				},
+				{
+					HostPort:      0,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+				},
+			},
+			want: []types.PortMapping{
+				{
+					HostPort:      0,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         1,
+				},
+			},
+		},
+		{
+			name: "neighbor ports are not joined",
+			arg: []types.PortMapping{
+				{
+					HostPort:      0,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+				},
+				{
+					HostPort:      0,
+					ContainerPort: 81,
+					Protocol:      "tcp",
+				},
+			},
+			want: []types.PortMapping{
+				{
+					HostPort:      0,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         1,
+				},
+				{
+					HostPort:      0,
+					ContainerPort: 81,
+					Protocol:      "tcp",
+					Range:         1,
+				},
+			},
+		},
+		{
+			name: "overlapping range ports are joined",
+			arg: []types.PortMapping{
+				{
+					HostPort:      0,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         2,
+				},
+				{
+					HostPort:      0,
+					ContainerPort: 81,
+					Protocol:      "tcp",
+				},
+			},
+			want: []types.PortMapping{
+				{
+					HostPort:      0,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         2,
+				},
+			},
+		},
+		{
+			name: "four overlapping range ports are joined",
+			arg: []types.PortMapping{
+				{
+					HostPort:      0,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         3,
+				},
+				{
+					HostPort:      0,
+					ContainerPort: 81,
+					Protocol:      "tcp",
+				},
+				{
+					HostPort:      0,
+					ContainerPort: 82,
+					Protocol:      "tcp",
+					Range:         10,
+				},
+				{
+					HostPort:      0,
+					ContainerPort: 90,
+					Protocol:      "tcp",
+					Range:         5,
+				},
+			},
+			want: []types.PortMapping{
+				{
+					HostPort:      0,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         15,
+				},
+			},
+		},
+		{
+			name: "expose one tcp port",
+			arg2: map[uint16][]string{
+				8080: {"tcp"},
+			},
+			want: []types.PortMapping{
+				{
+					HostPort:      0,
+					ContainerPort: 8080,
+					Protocol:      "tcp",
+					Range:         1,
+				},
+			},
+		},
+		{
+			name: "expose already defined port",
+			arg: []types.PortMapping{
+				{
+					HostPort:      0,
+					ContainerPort: 8080,
+					Protocol:      "tcp",
+				},
+			},
+			arg2: map[uint16][]string{
+				8080: {"tcp"},
+			},
+			want: []types.PortMapping{
+				{
+					HostPort:      0,
+					ContainerPort: 8080,
+					Protocol:      "tcp",
+					Range:         1,
+				},
+			},
+		},
+		{
+			name: "expose different proto",
+			arg: []types.PortMapping{
+				{
+					HostPort:      0,
+					ContainerPort: 8080,
+					Protocol:      "tcp",
+				},
+			},
+			arg2: map[uint16][]string{
+				8080: {"udp"},
+			},
+			want: []types.PortMapping{
+				{
+					HostPort:      0,
+					ContainerPort: 8080,
+					Protocol:      "tcp",
+					Range:         1,
+				},
+				{
+					HostPort:      0,
+					ContainerPort: 8080,
+					Protocol:      "udp",
+					Range:         1,
+				},
+			},
+		},
+	}
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := ParsePortMapping(tt.arg, tt.arg2)
+			assert.NoError(t, err, "error is not nil")
+
+			// because we always get random host ports when it is set to 0 we cannot check that exactly
+			// check if it is not 0 and set to to 0 afterwards
+			for i := range got {
+				assert.Greater(t, got[i].HostPort, uint16(0), "host port is zero")
+				got[i].HostPort = 0
+			}
+
+			// use ElementsMatch instead of Equal because the order is not consistent
+			assert.ElementsMatch(t, tt.want, got, "got unexpected port mapping")
+		})
+	}
+}
+
+func TestParsePortMappingMixedHostPort(t *testing.T) {
+	tests := []struct {
+		name           string
+		arg            []types.PortMapping
+		want           []types.PortMapping
+		resetHostPorts []int
+	}{
+		{
+			name: "two ports one without a hostport set",
+			arg: []types.PortMapping{
+				{
+					HostPort:      0,
+					ContainerPort: 80,
+				},
+				{
+					HostPort:      8080,
+					ContainerPort: 8080,
+				},
+			},
+			want: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 8080,
+					Protocol:      "tcp",
+					Range:         1,
+				},
+				{
+					HostPort:      0,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         1,
+				},
+			},
+			resetHostPorts: []int{1},
+		},
+		{
+			name: "two ports one without a hostport set, inverted order",
+			arg: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 8080,
+				},
+				{
+					HostPort:      0,
+					ContainerPort: 80,
+				},
+			},
+			want: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 8080,
+					Protocol:      "tcp",
+					Range:         1,
+				},
+				{
+					HostPort:      0,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         1,
+				},
+			},
+			resetHostPorts: []int{1},
+		},
+		{
+			name: "three ports without host ports, one with a hostport set, , inverted order",
+			arg: []types.PortMapping{
+				{
+					HostPort:      0,
+					ContainerPort: 80,
+				},
+				{
+					HostPort:      0,
+					ContainerPort: 85,
+				},
+				{
+					HostPort:      0,
+					ContainerPort: 90,
+				},
+				{
+					HostPort:      8080,
+					ContainerPort: 8080,
+				},
+			},
+			want: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 8080,
+					Protocol:      "tcp",
+					Range:         1,
+				},
+				{
+					HostPort:      0,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         1,
+				},
+				{
+					HostPort:      0,
+					ContainerPort: 85,
+					Protocol:      "tcp",
+					Range:         1,
+				},
+				{
+					HostPort:      0,
+					ContainerPort: 90,
+					Protocol:      "tcp",
+					Range:         1,
+				},
+			},
+			resetHostPorts: []int{1, 2, 3},
+		},
+		{
+			name: "three ports without host ports, one with a hostport set",
+			arg: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 8080,
+				},
+				{
+					HostPort:      0,
+					ContainerPort: 90,
+				},
+				{
+					HostPort:      0,
+					ContainerPort: 85,
+				},
+				{
+					HostPort:      0,
+					ContainerPort: 80,
+				},
+			},
+			want: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 8080,
+					Protocol:      "tcp",
+					Range:         1,
+				},
+				{
+					HostPort:      0,
+					ContainerPort: 80,
+					Protocol:      "tcp",
+					Range:         1,
+				},
+				{
+					HostPort:      0,
+					ContainerPort: 85,
+					Protocol:      "tcp",
+					Range:         1,
+				},
+				{
+					HostPort:      0,
+					ContainerPort: 90,
+					Protocol:      "tcp",
+					Range:         1,
+				},
+			},
+			resetHostPorts: []int{1, 2, 3},
+		},
+	}
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := ParsePortMapping(tt.arg, nil)
+			assert.NoError(t, err, "error is not nil")
+
+			// because we always get random host ports when it is set to 0 we cannot check that exactly
+			// use resetHostPorts to know which port element is 0
+			for _, num := range tt.resetHostPorts {
+				assert.Greater(t, got[num].HostPort, uint16(0), "host port is zero")
+				got[num].HostPort = 0
+			}
+
+			assert.Equal(t, tt.want, got, "got unexpected port mapping")
+		})
+	}
+}
+
+func TestParsePortMappingError(t *testing.T) {
+	tests := []struct {
+		name string
+		arg  []types.PortMapping
+		err  string
+	}{
+		{
+			name: "container port is 0",
+			arg: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 0,
+					Protocol:      "tcp",
+				},
+			},
+			err: "container port number must be non-0",
+		},
+		{
+			name: "container port range exceeds max",
+			arg: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 65000,
+					Protocol:      "tcp",
+					Range:         10000,
+				},
+			},
+			err: "container port range exceeds maximum allowable port number",
+		},
+		{
+			name: "host port range exceeds max",
+			arg: []types.PortMapping{
+				{
+					HostPort:      60000,
+					ContainerPort: 1,
+					Protocol:      "tcp",
+					Range:         10000,
+				},
+			},
+			err: "host port range exceeds maximum allowable port number",
+		},
+		{
+			name: "invalid protocol",
+			arg: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "1",
+				},
+			},
+			err: "unrecognized protocol \"1\" in port mapping",
+		},
+		{
+			name: "invalid protocol 2",
+			arg: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Protocol:      "udp,u",
+				},
+			},
+			err: "unrecognized protocol \"u\" in port mapping",
+		},
+		{
+			name: "invalid ip address",
+			arg: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					HostIP:        "blah",
+				},
+			},
+			err: "invalid IP address \"blah\" in port mapping",
+		},
+		{
+			name: "invalid overalpping range",
+			arg: []types.PortMapping{
+				{
+					HostPort:      8080,
+					ContainerPort: 80,
+					Range:         5,
+				},
+				{
+					HostPort:      8081,
+					ContainerPort: 60,
+				},
+			},
+			err: "conflicting port mappings for host port 8081 (protocol tcp)",
+		},
+		{
+			name: "big port range with host port zero does not fit",
+			arg: []types.PortMapping{
+				{
+					HostPort:      0,
+					ContainerPort: 1,
+					Range:         65535,
+				},
+			},
+			err: "failed to find an open port to expose container port 1 with range 65535 on the host",
+		},
+		{
+			name: "big port range with host port zero does not fit",
+			arg: []types.PortMapping{
+				{
+					HostPort:      0,
+					ContainerPort: 80,
+					Range:         1,
+				},
+				{
+					HostPort:      0,
+					ContainerPort: 1000,
+					Range:         64535,
+				},
+			},
+			err: "failed to find an open port to expose container port 1000 with range 64535 on the host",
+		},
+	}
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			_, err := ParsePortMapping(tt.arg, nil)
+			assert.EqualError(t, err, tt.err, "error does not match")
+		})
+	}
+}