Files
podman/pkg/api/handlers/compat/images_push.go
Valentin Rothberg 5bdd571b1e compat API: allow enforcing short-names resolution to Docker Hub
The Docker-compatible REST API has historically behaved just as the rest
of Podman and Buildah (and the atomic Docker in older RHEL/Fedora) where
`containers-registries.conf` is centrally controlling which registries
a short name may resolve to during pull or local image lookups.  Please
refer to a blog for more details [1].

Docker, however, is only resolving short names to docker.io which has
been reported (see #12320) to break certain clients who rely on this
behavior.  In order to support this scenario, `containers.conf(5)`
received a new option to control whether Podman's compat API resolves
to docker.io only or behaves as before.

Most endpoints allow for directly normalizing parameters that represent
an image.  If set in containers.conf, Podman will then normalize the
references directly to docker.io.  The build endpoint is an outlier
since images are also referenced in Dockerfiles.  The Buildah API,
however, supports specifying a custom `types.SystemContext` in which
we can set a field that enforces short-name resolution to docker.io
in `c/image/pkg/shortnames`.

Notice that this a "hybrid" approach of doing the normalization directly
in the compat endpoints *and* in `pkg/shortnames` by passing a system
context.  Doing such a hybrid approach is neccessary since the compat
and the libpod endpoints share the same `libimage.Runtime` which makes
a global enforcement via the `libimage.Runtime.systemContext`
impossible.  Having two separate runtimes for the compat and the libpod
endpoints seems risky and not generally applicable to all endpoints.

[1] https://www.redhat.com/sysadmin/container-image-short-names

Fixes: #12320
Signed-off-by: Valentin Rothberg <rothberg@redhat.com>
2021-11-30 14:22:52 +01:00

209 lines
6.1 KiB
Go

package compat
import (
"encoding/json"
"fmt"
"io/ioutil"
"net/http"
"strings"
"github.com/containers/image/v5/types"
"github.com/containers/podman/v3/libpod"
"github.com/containers/podman/v3/pkg/api/handlers/utils"
api "github.com/containers/podman/v3/pkg/api/types"
"github.com/containers/podman/v3/pkg/auth"
"github.com/containers/podman/v3/pkg/domain/entities"
"github.com/containers/podman/v3/pkg/domain/infra/abi"
"github.com/containers/storage"
"github.com/docker/docker/pkg/jsonmessage"
"github.com/gorilla/schema"
"github.com/pkg/errors"
"github.com/sirupsen/logrus"
)
// PushImage is the handler for the compat http endpoint for pushing images.
func PushImage(w http.ResponseWriter, r *http.Request) {
decoder := r.Context().Value(api.DecoderKey).(*schema.Decoder)
runtime := r.Context().Value(api.RuntimeKey).(*libpod.Runtime)
digestFile, err := ioutil.TempFile("", "digest.txt")
if err != nil {
utils.Error(w, "unable to create digest tempfile", http.StatusInternalServerError, errors.Wrap(err, "unable to create tempfile"))
return
}
defer digestFile.Close()
// Now use the ABI implementation to prevent us from having duplicate
// code.
imageEngine := abi.ImageEngine{Libpod: runtime}
query := struct {
All bool `schema:"all"`
Compress bool `schema:"compress"`
Destination string `schema:"destination"`
Format string `schema:"format"`
TLSVerify bool `schema:"tlsVerify"`
Tag string `schema:"tag"`
}{
// This is where you can override the golang default value for one of fields
TLSVerify: true,
}
if err := decoder.Decode(&query, r.URL.Query()); err != nil {
utils.Error(w, "Something went wrong.", http.StatusBadRequest, errors.Wrapf(err, "failed to parse parameters for %s", r.URL.String()))
return
}
// Note that Docker's docs state "Image name or ID" to be in the path
// parameter but it really must be a name as Docker does not allow for
// pushing an image by ID.
imageName := strings.TrimSuffix(utils.GetName(r), "/push") // GetName returns the entire path
if query.Tag != "" {
imageName += ":" + query.Tag
}
if _, err := utils.ParseStorageReference(imageName); err != nil {
utils.Error(w, http.StatusText(http.StatusBadRequest), http.StatusBadRequest,
errors.Wrapf(err, "image source %q is not a containers-storage-transport reference", imageName))
return
}
possiblyNormalizedName, err := utils.NormalizeToDockerHub(r, imageName)
if err != nil {
utils.Error(w, "Something went wrong.", http.StatusInternalServerError, errors.Wrap(err, "error normalizing image"))
return
}
imageName = possiblyNormalizedName
if _, _, err := runtime.LibimageRuntime().LookupImage(possiblyNormalizedName, nil); err != nil {
utils.ImageNotFound(w, imageName, errors.Wrapf(err, "failed to find image %s", imageName))
return
}
authconf, authfile, key, err := auth.GetCredentials(r)
if err != nil {
utils.Error(w, "Something went wrong.", http.StatusBadRequest, errors.Wrapf(err, "failed to parse %q header for %s", key, r.URL.String()))
return
}
defer auth.RemoveAuthfile(authfile)
var username, password string
if authconf != nil {
username = authconf.Username
password = authconf.Password
}
options := entities.ImagePushOptions{
All: query.All,
Authfile: authfile,
Compress: query.Compress,
Format: query.Format,
Password: password,
Username: username,
DigestFile: digestFile.Name(),
Quiet: true,
Progress: make(chan types.ProgressProperties),
}
if _, found := r.URL.Query()["tlsVerify"]; found {
options.SkipTLSVerify = types.NewOptionalBool(!query.TLSVerify)
}
var destination string
if _, found := r.URL.Query()["destination"]; found {
destination = query.Destination
} else {
destination = imageName
}
flush := func() {}
if flusher, ok := w.(http.Flusher); ok {
flush = flusher.Flush
}
w.WriteHeader(http.StatusOK)
w.Header().Set("Content-Type", "application/json")
flush()
var report jsonmessage.JSONMessage
enc := json.NewEncoder(w)
enc.SetEscapeHTML(true)
report.Status = fmt.Sprintf("The push refers to repository [%s]", imageName)
if err := enc.Encode(report); err != nil {
logrus.Warnf("Failed to json encode error %q", err.Error())
}
flush()
pushErrChan := make(chan error)
go func() {
pushErrChan <- imageEngine.Push(r.Context(), imageName, destination, options)
}()
loop: // break out of for/select infinite loop
for {
report = jsonmessage.JSONMessage{}
select {
case e := <-options.Progress:
switch e.Event {
case types.ProgressEventNewArtifact:
report.Status = "Preparing"
case types.ProgressEventRead:
report.Status = "Pushing"
report.Progress = &jsonmessage.JSONProgress{
Current: int64(e.Offset),
Total: e.Artifact.Size,
}
case types.ProgressEventSkipped:
report.Status = "Layer already exists"
case types.ProgressEventDone:
report.Status = "Pushed"
}
report.ID = e.Artifact.Digest.Encoded()[0:12]
if err := enc.Encode(report); err != nil {
logrus.Warnf("Failed to json encode error %q", err.Error())
}
flush()
case err := <-pushErrChan:
if err != nil {
var msg string
if errors.Is(err, storage.ErrImageUnknown) {
msg = "An image does not exist locally with the tag: " + imageName
} else {
msg = err.Error()
}
report.Error = &jsonmessage.JSONError{
Message: msg,
}
report.ErrorMessage = msg
if err := enc.Encode(report); err != nil {
logrus.Warnf("Failed to json encode error %q", err.Error())
}
flush()
break loop
}
digestBytes, err := ioutil.ReadAll(digestFile)
if err != nil {
report.Error = &jsonmessage.JSONError{
Message: err.Error(),
}
report.ErrorMessage = err.Error()
if err := enc.Encode(report); err != nil {
logrus.Warnf("Failed to json encode error %q", err.Error())
}
flush()
break loop
}
tag := query.Tag
if tag == "" {
tag = "latest"
}
report.Status = fmt.Sprintf("%s: digest: %s", tag, string(digestBytes))
if err := enc.Encode(report); err != nil {
logrus.Warnf("Failed to json encode error %q", err.Error())
}
flush()
break loop // break out of for/select infinite loop
}
}
}