cmd/uplink: use arguments in share command as allowed path prefixes

Fixes Least Authority Issue F:
https://storjlabs.atlassian.net/browse/V3-3409

If the --allowed-path-prefix flag is not set to the `share` command, any
command arguments will be used as allowed path prefixes.

This patch also improves the output of the `share` command to print the
state of all restrictions, so users can confirm they match their
intention.

Change-Id: Id1b4df20b182d3fe04cb2196feea090975fce8b4

cmd/uplink/cmd/share.go

@@ -7,9 +7,9 @@ import (
 	"fmt"
 	"io/ioutil"
 	"path/filepath"
+	"strings"
 	"time"
 
-	"github.com/gogo/protobuf/proto"
 	"github.com/spf13/cobra"
 	"github.com/zeebo/errs"
 
@@ -30,7 +30,7 @@ var shareCfg struct {
 	Writeonly         bool     `default:"false" help:"implies disallow_reads and disallow_lists"`
 	NotBefore         string   `help:"disallow access before this time"`
 	NotAfter          string   `help:"disallow access after this time"`
-	AllowedPathPrefix []string `help:"whitelist of bucket path prefixes to require"`
+	AllowedPathPrefix []string `help:"whitelist of path prefixes to require, overrides the [allowed-path-prefix] arguments"`
 	ExportTo          string   `default:"" help:"path to export the shared scope to"`
 
 	// Share requires information about the current scope
@@ -42,8 +42,8 @@ func init() {
 	// above, and addCmd adds a whole lot more than we want.
 
 	shareCmd := &cobra.Command{
-		Use:   "share",
-		Short: "Creates a possibly restricted api key",
+		Use:   "share [allowed-path-prefix]...",
+		Short: "Shares restricted access to objects.",
 		RunE:  shareMain,
 	}
 	RootCmd.AddCommand(shareCmd)
@@ -86,6 +86,14 @@ func shareMain(cmd *cobra.Command, args []string) (err error) {
 		return err
 	}
 
+	if len(shareCfg.AllowedPathPrefix) == 0 {
+		// if the --allowed-path-prefix flag is not set,
+		// use any arguments as allowed path prefixes
+		for _, arg := range args {
+			shareCfg.AllowedPathPrefix = append(shareCfg.AllowedPathPrefix, strings.Split(arg, ",")...)
+		}
+	}
+
 	var restrictions []libuplink.EncryptionRestriction
 	for _, path := range shareCfg.AllowedPathPrefix {
 		p, err := fpath.New(path)
@@ -127,23 +135,6 @@ func shareMain(cmd *cobra.Command, args []string) (err error) {
 	caveat.NotBefore = notBefore
 	caveat.NotAfter = notAfter
 
-	{
-		// Times don't marshal very well with MarshalTextString, and the nonce doesn't
-		// matter to humans, so handle those explicitly and then dispatch to the generic
-		// routine to avoid having to print all the things individually.
-		caveatCopy := proto.Clone(&caveat).(*macaroon.Caveat)
-		caveatCopy.Nonce = nil
-		if caveatCopy.NotBefore != nil {
-			fmt.Println("not before:", caveatCopy.NotBefore.Truncate(0).Format(shareISO8601))
-			caveatCopy.NotBefore = nil
-		}
-		if caveatCopy.NotAfter != nil {
-			fmt.Println("not after:", caveatCopy.NotAfter.Truncate(0).Format(shareISO8601))
-			caveatCopy.NotAfter = nil
-		}
-		fmt.Print(proto.MarshalTextString(caveatCopy))
-	}
-
 	key, err = key.Restrict(caveat)
 	if err != nil {
 		return err
@@ -165,9 +156,20 @@ func shareMain(cmd *cobra.Command, args []string) (err error) {
 		return err
 	}
 
-	fmt.Println("api key:", key.Serialize())
-	fmt.Println("enc ctx:", accessData)
-	fmt.Println("scope  :", scopeData)
+	fmt.Println("=========== INTERNAL SCOPE INFO =========================================================")
+	fmt.Println("Satellite :", scope.SatelliteAddr)
+	fmt.Println("API Key   :", key.Serialize())
+	fmt.Println("Enc Access:", accessData)
+	fmt.Println("=========== SHARE RESTRICTIONS ==========================================================")
+	fmt.Println("Reads     :", formatPermission(!caveat.GetDisallowReads()))
+	fmt.Println("Writes    :", formatPermission(!caveat.GetDisallowWrites()))
+	fmt.Println("Lists     :", formatPermission(!caveat.GetDisallowLists()))
+	fmt.Println("Deletes   :", formatPermission(!caveat.GetDisallowDeletes()))
+	fmt.Println("Not Before:", formatTimeRestriction(caveat.NotBefore))
+	fmt.Println("Not After :", formatTimeRestriction(caveat.NotAfter))
+	fmt.Println("Paths     :", formatPaths(restrictions))
+	fmt.Println("=========== SERIALIZED SCOPE WITH THE ABOVE RESTRICTIONS TO SHARE WITH OTHERS ===========")
+	fmt.Println("Scope     :", scopeData)
 
 	if shareCfg.ExportTo != "" {
 		// convert to an absolute path, mostly for output purposes.
@@ -178,7 +180,40 @@ func shareMain(cmd *cobra.Command, args []string) (err error) {
 		if err := ioutil.WriteFile(exportTo, []byte(scopeData+"\n"), 0600); err != nil {
 			return Error.Wrap(err)
 		}
-		fmt.Printf("exported to %s\n", exportTo)
+		fmt.Println("Exported to:", exportTo)
 	}
 	return nil
 }
+
+func formatPermission(allowed bool) string {
+	if allowed {
+		return "Allowed"
+	}
+	return "Disallowed"
+}
+
+func formatTimeRestriction(t *time.Time) string {
+	if t == nil {
+		return "No restriction"
+	}
+	return formatTime(*t)
+}
+
+func formatPaths(restrictions []libuplink.EncryptionRestriction) string {
+	if len(restrictions) == 0 {
+		return "WARNING! The entire project is shared!"
+	}
+
+	var paths []string
+	for _, restriction := range restrictions {
+		path := "sj://" + restriction.Bucket
+		if len(restriction.PathPrefix) == 0 {
+			path += " (entire bucket)"
+		} else {
+			path += "/" + restriction.PathPrefix
+		}
+		paths = append(paths, path)
+	}
+
+	return strings.Join(paths, "\n            ")
+}