diff options
Diffstat (limited to 'vendor')
-rw-r--r-- | vendor/github.com/containers/common/pkg/defaultnet/default_network.go | 222 | ||||
-rw-r--r-- | vendor/modules.txt | 1 |
2 files changed, 223 insertions, 0 deletions
diff --git a/vendor/github.com/containers/common/pkg/defaultnet/default_network.go b/vendor/github.com/containers/common/pkg/defaultnet/default_network.go new file mode 100644 index 000000000..9b32241d6 --- /dev/null +++ b/vendor/github.com/containers/common/pkg/defaultnet/default_network.go @@ -0,0 +1,222 @@ +package defaultnet + +import ( + "bytes" + "encoding/json" + "fmt" + "io/ioutil" + "net" + "os" + "path/filepath" + "regexp" + "text/template" + + "github.com/pkg/errors" + "github.com/sirupsen/logrus" +) + +// TODO: A smarter implementation would make sure cni-podman0 was unused before +// making the default, and adjust if necessary +const networkTemplate = `{ + "cniVersion": "0.4.0", + "name": "{{{{.Name}}}}", + "plugins": [ + { + "type": "bridge", + "bridge": "cni-podman0", + "isGateway": true, + "ipMasq": true, + "hairpinMode": true, + "ipam": { + "type": "host-local", + "routes": [{ "dst": "0.0.0.0/0" }], + "ranges": [ + [ + { + "subnet": "{{{{.Subnet}}}}", + "gateway": "{{{{.Gateway}}}}" + } + ] + ] + } + }, +{{{{- if (eq .Machine true) }}}} + { + "type": "podman-machine", + "capabilities": { + "portMappings": true + } + }, +{{{{- end}}}} + { + "type": "portmap", + "capabilities": { + "portMappings": true + } + }, + { + "type": "firewall" + }, + { + "type": "tuning" + } + ] +} +` + +var ( + // Borrowed from Podman, modified to remove dashes and periods. + nameRegex = regexp.MustCompile("^[a-zA-Z0-9][a-zA-Z0-9_]*$") +) + +// Used to pass info into the template engine +type networkInfo struct { + Name string + Subnet string + Gateway string + Machine bool +} + +// The most trivial definition of a CNI network possible for our use here. +// We need the name, and nothing else. +type network struct { + Name string `json:"name"` +} + +// Create makes the CNI default network, if necessary. +// Accepts the name and subnet of the network to create (a standard template +// will be used, with these values plugged in), the configuration directory +// where CNI configs are stored (to verify if a named configuration already +// exists), an exists directory (where a sentinel file will be stored, to ensure +// the network is only made once), and an isMachine bool (to determine whether +// the machine block will be added to the config). +// Create first checks if a default network has already been created via the +// presence of a sentinel file. If it does exist, it returns immediately without +// error. +// It next checks if a CNI network with the given name already exists. In that +// case, it creates the sentinel file and returns without error. +// If neither of these are true, the default network is created. +func Create(name, subnet, configDir, existsDir string, isMachine bool) error { + // TODO: Should probably regex name to make sure it's valid. + if name == "" || subnet == "" || configDir == "" || existsDir == "" { + return errors.Errorf("must provide values for all arguments to MakeDefaultNetwork") + } + if !nameRegex.MatchString(name) { + return errors.Errorf("invalid default network name %s - letters, numbers, and underscores only", name) + } + + sentinelFile := filepath.Join(existsDir, "defaultCNINetExists") + + // Check if sentinel file exists, return immediately if it does. + if _, err := os.Stat(sentinelFile); err == nil { + return nil + } + + // Create the sentinel file if it doesn't exist, so subsequent checks + // don't need to go further. + file, err := os.Create(sentinelFile) + if err != nil { + return err + } + file.Close() + + // We may need to make the config dir. + if err := os.MkdirAll(configDir, 0755); err != nil && !os.IsExist(err) { + return errors.Wrapf(err, "error creating CNI configuration directory") + } + + // Check all networks in the CNI conflist. + files, err := ioutil.ReadDir(configDir) + if err != nil { + return errors.Wrapf(err, "error reading CNI configuration directory") + } + if len(files) > 0 { + configPaths := make([]string, 0, len(files)) + for _, path := range files { + if !path.IsDir() && filepath.Ext(path.Name()) == ".conflist" { + configPaths = append(configPaths, filepath.Join(configDir, path.Name())) + } + } + for _, config := range configPaths { + configName, err := getConfigName(config) + if err != nil { + logrus.Errorf("Error reading CNI configuration file: %v", err) + continue + } + if configName == name { + return nil + } + } + } + + // We need to make the config. + // Get subnet and gateway. + _, ipNet, err := net.ParseCIDR(subnet) + if err != nil { + return errors.Wrapf(err, "default network subnet %s is invalid", subnet) + } + + ones, bits := ipNet.Mask.Size() + if ones == bits { + return errors.Wrapf(err, "default network subnet %s is to small", subnet) + } + gateway := make(net.IP, len(ipNet.IP)) + // copy the subnet ip to the gateway so we can modify it + copy(gateway, ipNet.IP) + // the default gateway should be the first ip in the subnet + gateway[len(gateway)-1]++ + + netInfo := new(networkInfo) + netInfo.Name = name + netInfo.Gateway = gateway.String() + netInfo.Subnet = ipNet.String() + netInfo.Machine = isMachine + + templ, err := template.New("network_template").Delims("{{{{", "}}}}").Parse(networkTemplate) + if err != nil { + return errors.Wrapf(err, "error compiling template for default network") + } + var output bytes.Buffer + if err := templ.Execute(&output, netInfo); err != nil { + return errors.Wrapf(err, "error executing template for default network") + } + + // Next, we need to place the config on disk. + // Loop through possible indexes, with a limit of 100 attempts. + created := false + for i := 87; i < 187; i++ { + configFile, err := os.OpenFile(filepath.Join(configDir, fmt.Sprintf("%d-%s.conflist", i, name)), os.O_CREATE|os.O_EXCL|os.O_WRONLY, 0644) + if err != nil { + logrus.Infof("Attempt to create default CNI network config file failed: %v", err) + continue + } + defer configFile.Close() + + created = true + + // Success - file is open. Write our buffer to it. + if _, err := configFile.Write(output.Bytes()); err != nil { + return errors.Wrapf(err, "error writing default CNI config to file") + } + break + } + if !created { + return errors.Errorf("no available default network configuration file was found") + } + + return nil +} + +// Get the name of the configuration contained in a given conflist file. Accepts +// the full path of a .conflist CNI configuration. +func getConfigName(file string) (string, error) { + contents, err := ioutil.ReadFile(file) + if err != nil { + return "", err + } + config := new(network) + if err := json.Unmarshal(contents, config); err != nil { + return "", errors.Wrapf(err, "error decoding CNI configuration %s", filepath.Base(file)) + } + return config.Name, nil +} diff --git a/vendor/modules.txt b/vendor/modules.txt index b4c2c6330..50f8e7338 100644 --- a/vendor/modules.txt +++ b/vendor/modules.txt @@ -102,6 +102,7 @@ github.com/containers/common/pkg/cgroupv2 github.com/containers/common/pkg/chown github.com/containers/common/pkg/completion github.com/containers/common/pkg/config +github.com/containers/common/pkg/defaultnet github.com/containers/common/pkg/filters github.com/containers/common/pkg/manifests github.com/containers/common/pkg/parse |