support policies, closes #12

cmd/internal/policy.go

@@ -0,0 +1,18 @@
+package internal
+
+import (
+	"fmt"
+
+	"github.com/hashicorp/go-multierror"
+	"within.website/olin/policy"
+)
+
+func ValidatePolicy(pol policy.Policy) error {
+	var err error
+
+	if pol.RamPageLimit > 2048 {
+		err = multierror.Append(err, fmt.Errorf("ram page limit is %d, which is over the limit of 2048", pol.RamPageLimit))
+	}
+
+	return err
+}

cmd/internal/topic.go

@@ -3,12 +3,13 @@ package internal
 import "github.com/rogpeppe/go-internal/txtar"
 
 // Topic name for wasmcloud -> executor communication
-const TopicName = "wasmcloud-to-executor-09d7e475-71ac-4bdd-be37-050af7a81c58"
+const TopicName = "exec"
 
 type ExecRequest struct {
 	WASMCID string            `json:"wasmcid"`
 	Name    string            `json:"name"`
 	Data    []byte            `json:"data"`
+	Policy  []byte            `json:"policy"`
 	ABI     ABI               `json:"abi"`
 	Env     map[string]string `json:"env"`
 	UUID    string            `json:"uuid"`

cmd/internal/types.go

@@ -8,6 +8,7 @@ const (
 )
 
 type Handler struct {
-	WASM []byte `json:"wasm"`
+	WASM   []byte `json:"wasm"`
-	ABI  string `json:"abi"`
+	Policy []byte `json:"policy"`
+	ABI    string `json:"abi"`
 }

cmd/wasmcloud-executor/main.go

@@ -21,6 +21,7 @@ import (
 	"github.com/rogpeppe/go-internal/txtar"
 	"tulpa.dev/within/wasmcloud/cmd/internal"
 	"tulpa.dev/within/wasmcloud/executor"
+	"within.website/olin/policy"
 )
 
 var (
@@ -136,8 +137,17 @@ func waitForNewWASM(ctx context.Context, wg *sync.WaitGroup, sh *shell.Shell, nc
 			LogSink:  logBuf,
 		}
 
+		pol, err := policy.Parse(er.Name+".policy", er.Policy)
+		if err != nil {
+			log.Printf("can't get policy: %v", err)
+			continue
+		}
+
+		c.Policy = &pol
+
 		result, err := executor.Run(c)
 		if err != nil {
+			fmt.Fprintln(logBuf, "can't run binary:", err)
 			log.Printf("can't run binary: %v", err)
 		}
 

cmd/wasmcloud/handler_create.go

@@ -15,10 +15,11 @@ import (
 
 	"github.com/google/subcommands"
 	"tulpa.dev/within/wasmcloud/cmd/internal"
+	"within.website/olin/policy"
 )
 
 type handlerCreateCmd struct {
-	abi string
+	abi, policyFile string
 }
 
 func (handlerCreateCmd) Name() string     { return "create" }
@@ -38,6 +39,7 @@ Flags:
 
 func (h *handlerCreateCmd) SetFlags(fs *flag.FlagSet) {
 	fs.StringVar(&h.abi, "abi", "cwa", "WebAssembly ABI to use for the handler")
+	fs.StringVar(&h.policyFile, "policy", "", "if set, use this policy file for the handler")
 }
 
 func (h handlerCreateCmd) Execute(ctx context.Context, fs *flag.FlagSet, _ ...interface{}) subcommands.ExitStatus {
@@ -57,6 +59,25 @@ func (h handlerCreateCmd) Execute(ctx context.Context, fs *flag.FlagSet, _ ...in
 		WASM: data,
 	}
 
+	if h.policyFile != "" {
+		data, err := ioutil.ReadFile(h.policyFile)
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		pol, err := policy.Parse(h.policyFile, data)
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		err = internal.ValidatePolicy(pol)
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		hdlr.Policy = data
+	}
+
 	bodyData, _ := json.Marshal(hdlr)
 	req, err := http.NewRequestWithContext(ctx, http.MethodPost, *apiServer+"/api/handler/create", bytes.NewBuffer(bodyData))
 	if err != nil {

cmd/wasmcloud/handler_update.go

@@ -15,10 +15,11 @@ import (
 
 	"github.com/google/subcommands"
 	"tulpa.dev/within/wasmcloud/cmd/internal"
+	"within.website/olin/policy"
 )
 
 type handlerUpdateCmd struct {
-	abi string
+	abi, policyFile string
 }
 
 func (handlerUpdateCmd) Name() string     { return "update" }
@@ -36,6 +37,7 @@ Flags:
 
 func (h *handlerUpdateCmd) SetFlags(fs *flag.FlagSet) {
 	fs.StringVar(&h.abi, "abi", "cwa", "WebAssembly ABI to use for the handler")
+	fs.StringVar(&h.policyFile, "policy", "", "if set, use this policy file for the handler")
 }
 
 func (h handlerUpdateCmd) Execute(ctx context.Context, fs *flag.FlagSet, _ ...interface{}) subcommands.ExitStatus {
@@ -56,6 +58,25 @@ func (h handlerUpdateCmd) Execute(ctx context.Context, fs *flag.FlagSet, _ ...in
 		WASM: data,
 	}
 
+	if h.policyFile != "" {
+		data, err := ioutil.ReadFile(h.policyFile)
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		pol, err := policy.Parse(h.policyFile, data)
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		err = internal.ValidatePolicy(pol)
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		hdlr.Policy = data
+	}
+
 	bodyData, _ := json.Marshal(hdlr)
 	req, err := http.NewRequestWithContext(ctx, http.MethodPost, *apiServer+"/api/handler/update?name="+hname, bytes.NewBuffer(bodyData))
 	if err != nil {

cmd/wasmcloud/run.go

@@ -17,12 +17,12 @@ import (
 	"github.com/perlin-network/life/exec"
 	"github.com/rogpeppe/go-internal/txtar"
 	"tulpa.dev/within/wasmcloud/executor"
+	"within.website/olin/policy"
 )
 
 type runCmd struct {
 	funcName, abi string
-	gasLimit      uint64
+	policyFile    string
-	ramLimit      int
 }
 
 func (runCmd) Name() string { return "run" }
@@ -33,7 +33,6 @@ func (runCmd) Usage() string {
 	return `wasmcloud run [options] <file.wasm>
 
 $ wasmcloud run olinfetch.wasm
-$ wasmcloud run -abi dagger -func-name dagger_main hello_dagger.wasm
 
 Run a given webassembly binary and return the output.
 
@@ -47,8 +46,7 @@ Flags:
 func (r *runCmd) SetFlags(fs *flag.FlagSet) {
 	fs.StringVar(&r.funcName, "func-name", "_start", "entrypoint function to call")
 	fs.StringVar(&r.abi, "abi", "cwa", "ABI to use")
-	fs.Uint64Var(&r.gasLimit, "gas-limit", 1048576, "number of wasm instructions per execution")
+	fs.StringVar(&r.policyFile, "policy", "", "if set, the policy file to use")
-	fs.IntVar(&r.ramLimit, "ram-limit", 128, "number of wasm pages that can be used")
 }
 
 func (r runCmd) Execute(ctx context.Context, fs *flag.FlagSet, _ ...interface{}) subcommands.ExitStatus {
@@ -86,9 +84,7 @@ func (r runCmd) Execute(ctx context.Context, fs *flag.FlagSet, _ ...interface{})
 	var stdin bytes.Buffer
 	c := executor.Config{
 		VMConfig: exec.VMConfig{
-			GasLimit:                 r.gasLimit,
 			ReturnOnGasLimitExceeded: true,
-			MaxMemoryPages:           r.ramLimit,
 		},
 
 		Name:     filepath.Base(fname),
@@ -101,6 +97,22 @@ func (r runCmd) Execute(ctx context.Context, fs *flag.FlagSet, _ ...interface{})
 		LogSink:  logBuf,
 	}
 
+	if r.policyFile != "" {
+		data, err := ioutil.ReadFile(r.policyFile)
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		pol, err := policy.Parse(r.policyFile, data)
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		c.VMConfig.MaxMemoryPages = int(pol.RamPageLimit)
+		c.VMConfig.GasLimit = uint64(pol.GasLimit)
+		c.Policy = &pol
+	}
+
 	result, err := executor.Run(c)
 	if err != nil {
 		log.Printf("can't run binary: %v", err)

cmd/wasmcloudd/handler.go

@@ -16,6 +16,7 @@ import (
 	"within.website/ln"
 	"within.website/ln/opname"
 	"within.website/olin/namegen"
+	"within.website/olin/policy"
 )
 
 func deleteHandler(w http.ResponseWriter, r *http.Request, u *User) {
@@ -72,6 +73,15 @@ func updateHandler(w http.ResponseWriter, r *http.Request, u *User) {
 		return
 	}
 
+	if len(uHdlr.Policy) != 0 {
+		err = validatePolicy(name, uHdlr.Policy)
+		if err != nil {
+			ln.Error(ctx, err)
+			http.Error(w, "policy validation failure", http.StatusBadRequest)
+			return
+		}
+	}
+
 	cid, err := uploadHandler(uHdlr)
 	if err != nil {
 		ln.Error(ctx, err)
@@ -79,6 +89,7 @@ func updateHandler(w http.ResponseWriter, r *http.Request, u *User) {
 		return
 	}
 
+	hdlr.Policy = uHdlr.Policy
 	hdlr.Path = cid
 	if err := db.Save(&hdlr).Error; err != nil {
 		ln.Error(ctx, err)
@@ -89,6 +100,15 @@ func updateHandler(w http.ResponseWriter, r *http.Request, u *User) {
 	json.NewEncoder(w).Encode(hdlr)
 }
 
+func validatePolicy(name string, data []byte) error {
+	pol, err := policy.Parse(name+".policy", data)
+	if err != nil {
+		return err
+	}
+
+	return internal.ValidatePolicy(pol)
+}
+
 func uploadHandler(hdlr internal.Handler) (string, error) {
 	sh := shell.NewShell(*ipfsURL)
 
@@ -135,6 +155,19 @@ func createHandler(w http.ResponseWriter, r *http.Request, u *User) {
 		return
 	}
 
+	n := namegen.Next()
+
+	if len(hdlr.Policy) == 0 {
+		hdlr.Policy = []byte(defaultPolicy)
+	}
+
+	err = validatePolicy(n, hdlr.Policy)
+	if err != nil {
+		ln.Error(ctx, err)
+		http.Error(w, "policy validation failure", http.StatusBadRequest)
+		return
+	}
+
 	cid, err := uploadHandler(hdlr)
 	if err != nil {
 		ln.Error(ctx, err)
@@ -142,12 +175,12 @@ func createHandler(w http.ResponseWriter, r *http.Request, u *User) {
 		return
 	}
 
-	n := namegen.Next()
 	h := Handler{
 		Name:   n,
 		User:   *u,
 		UserID: u.ID,
 		Path:   cid,
+		Policy: hdlr.Policy,
 	}
 
 	if err := db.Save(&h).Error; err != nil {

cmd/wasmcloudd/handler_invoke.go

@@ -23,7 +23,8 @@ func runHandler(ctx context.Context, hdlr Handler, timeout time.Duration, messag
 			"RUN_ID":      execID,
 			"MAGIC_CONCH": "yes",
 		},
-		UUID: execID,
+		UUID:   execID,
+		Policy: hdlr.Policy,
 	}
 
 	encData, err := json.Marshal(er)

cmd/wasmcloudd/models.go

@@ -37,6 +37,7 @@ type Handler struct {
 	gorm.Model
 	Name   string `gorm:"unique;not null"`
 	Path   string
+	Policy []byte
 	UserID uint `json:"-"`
 	User   User `json:"-"`
 }

cmd/wasmcloudd/policy.go

@@ -0,0 +1,14 @@
+package main
+
+const defaultPolicy = `## The default policy
+
+allow (
+  ^null://$
+  ^random://$
+  ^zero://$
+  ^https://xena.greedo.xeserv.us/files/hello_olin.txt$
+)
+
+ram-page-limit 128
+gas-limit 1048576
+`

executor/executor.go

@@ -15,6 +15,7 @@ import (
 	"github.com/perlin-network/life/exec"
 	"github.com/rogpeppe/go-internal/txtar"
 	"within.website/olin/abi/cwa"
+	"within.website/olin/policy"
 )
 
 var (
@@ -24,6 +25,7 @@ var (
 type Config struct {
 	exec.VMConfig
 
+	Policy         *policy.Policy
 	Name           string
 	FuncName       string
 	Env            map[string]string
@@ -77,7 +79,8 @@ func Run(c Config) (*Result, error) {
 	p.Stdout = c.Stdout
 	p.Stderr = c.Stderr
 	p.Logger = log.New(io.MultiWriter(c.LogSink, os.Stdout), c.Name+" ", log.LstdFlags)
-	p.HC.Transport = WasmcloudBrandingTransport(c.Name, p.HC.Transport)
+	p.HC.Transport = WasmcloudBrandingTransport(c.Name, http.DefaultTransport)
+	p.Policy = c.Policy
 
 	gp := &compiler.SimpleGasPolicy{GasPerInstruction: 1}
 	vm, err := exec.NewVirtualMachine(c.Binary, c.VMConfig, p, gp)
@@ -92,9 +95,13 @@ func Run(c Config) (*Result, error) {
 
 	pagesBefore := len(vm.Memory) / 65536
 	begin := time.Now()
-	ret, err := vm.Run(main)
+	ret, err := vm.RunWithGasLimit(main, int(c.Policy.GasLimit))
 	if err != nil {
-		return nil, err
+		vm.PrintStackTrace()
+		return &Result{
+			Status:    -2,
+			StartTime: begin,
+		}, err
 	}
 	dur := time.Since(begin)
 

go.mod

@@ -11,8 +11,10 @@ require (
 	github.com/google/uuid v1.1.1
 	github.com/gorilla/mux v1.7.3
 	github.com/gosuri/uitable v0.0.4
+	github.com/hashicorp/go-multierror v1.0.0
 	github.com/ipfs/go-ipfs-api v0.0.2
 	github.com/jinzhu/gorm v1.9.11
+	github.com/kr/pretty v0.1.0
 	github.com/lib/pq v1.1.1
 	github.com/manifoldco/promptui v0.6.0
 	github.com/mattn/go-sqlite3 v2.0.1+incompatible
@@ -20,6 +22,7 @@ require (
 	github.com/nats-io/nats.go v1.9.1
 	github.com/perlin-network/life v0.0.0-20191203030451-05c0e0f7eaea
 	github.com/rogpeppe/go-internal v1.5.0
+	github.com/rogpeppe/gohack v1.0.2 // indirect
 	golang.org/x/crypto v0.0.0-20190923035154-9ee001bba392
 	within.website/ln v0.7.0
 	within.website/olin v0.4.1-0.20191214133128-bde4927fad6b

go.sum

@@ -143,7 +143,9 @@ github.com/gxed/hashland/keccakpg v0.0.1 h1:wrk3uMNaMxbXiHibbPO4S0ymqJMm41WiudyF
 github.com/gxed/hashland/keccakpg v0.0.1/go.mod h1:kRzw3HkwxFU1mpmPP8v1WyQzwdGfmKFJ6tItnhQ67kU=
 github.com/gxed/hashland/murmur3 v0.0.1 h1:SheiaIt0sda5K+8FLz952/1iWS9zrnKsEJaOJu4ZbSc=
 github.com/gxed/hashland/murmur3 v0.0.1/go.mod h1:KjXop02n4/ckmZSnY2+HKcLud/tcmvhST0bie/0lS48=
+github.com/hashicorp/errwrap v1.0.0 h1:hLrqtEDnRye3+sgx6z4qVLNuviH3MR5aQ0ykNJa/UYA=
 github.com/hashicorp/errwrap v1.0.0/go.mod h1:YH+1FKiLXxHSkmPseP+kNlulaMuP3n2brvKWEqk/Jc4=
+github.com/hashicorp/go-multierror v1.0.0 h1:iVjPR7a6H0tWELX5NxNe7bYopibicUzc7uPribsnS6o=
 github.com/hashicorp/go-multierror v1.0.0/go.mod h1:dHtQlpGsu+cZNNAkkCN/P3hoUDHhCYQXV3UM06sGGrk=
 github.com/hashicorp/golang-lru v0.5.0/go.mod h1:/m3WP610KZHVQ1SGc6re/UDhFvYD7pJ4Ao+sR/qLZy8=
 github.com/hpcloud/tail v1.0.0/go.mod h1:ab1qPbhIpdTxEkNHXyeSf5vhxWSCs/tWer42PpOxQnU=
@@ -299,8 +301,11 @@ github.com/prometheus/procfs v0.0.0-20190117184657-bf6a532e95b1/go.mod h1:c3At6R
 github.com/prometheus/procfs v0.0.2/go.mod h1:TjEm7ze935MbeOT/UhFTIMYKhuLP4wbCsTZCD3I8kEA=
 github.com/prometheus/procfs v0.0.5/go.mod h1:4A/X28fw3Fc593LaREMrKMqOKvUAntwMDaekg4FpcdQ=
 github.com/rcrowley/go-metrics v0.0.0-20181016184325-3113b8401b8a/go.mod h1:bCqnVzQkZxMG4s8nGwiZ5l3QUCyqpo9Y+/ZMZ9VjZe4=
+github.com/rogpeppe/go-internal v1.0.0/go.mod h1:M8bDsm7K2OlrFYOpmOWEs/qY81heoFRclV5y23lUDJ4=
 github.com/rogpeppe/go-internal v1.5.0 h1:Usqs0/lDK/NqTkvrmKSwA/3XkZAs7ZAW/eLeQ2MVBTw=
 github.com/rogpeppe/go-internal v1.5.0/go.mod h1:xXDCJY+GAPziupqXw64V24skbSoqbTEfhy4qGm1nDQc=
+github.com/rogpeppe/gohack v1.0.2 h1:lYiGLFzvZC3RvzeE4GoUV3nTecDxTpVusVsQY4nAXGc=
+github.com/rogpeppe/gohack v1.0.2/go.mod h1:DE8wqaJRPvHU0fden5cSYy7ar2dTbbccPT/eeOYcbcE=
 github.com/sendgrid/rest v2.4.1+incompatible/go.mod h1:kXX7q3jZtJXK5c5qK83bSGMdV6tsOE70KbHoqJls4lE=
 github.com/sirupsen/logrus v1.2.0/go.mod h1:LxeOpSwHxABJmUn/MG1IvRgCAasNZTLOkJPxbbu5VWo=
 github.com/sirupsen/logrus v1.4.2/go.mod h1:tLMulIdttU9McNUspp0xgXVQah82FyeX6MwdIuYE2rE=
@@ -434,6 +439,7 @@ gopkg.in/alecthomas/kingpin.v3-unstable v3.0.0-20171010053543-63abe20a23e2/go.mo
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127 h1:qIbj1fsPNlZgppZ+VLlY7N33q108Sa+fhmuc+sWQYwY=
 gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/errgo.v2 v2.1.0 h1:0vLT13EuvQ0hNvakwLuFZ/jYrLp5F3kcWHXdRggjCE8=
 gopkg.in/errgo.v2 v2.1.0/go.mod h1:hNsd1EY+bozCKY1Ytp96fpM3vjJbqLJn88ws8XvfDNI=
 gopkg.in/fsnotify.v1 v1.4.7/go.mod h1:Tz8NjZHkW78fSQdbUxIjBTcgA1z1m8ZHf0WmKUhAMys=
 gopkg.in/tomb.v1 v1.0.0-20141024135613-dd632973f1e7/go.mod h1:dt/ZhP58zS4L8KSrWDmTeBkI65Dw0HsyUHuEVlX15mw=