Finalize lexer,parser, interpreter implementations

Author: foxcpp

cmd/sieve-run/main.go

@@ -0,0 +1,75 @@
+package main
+
+import (
+	"bufio"
+	"context"
+	"flag"
+	"log"
+	"net/textproto"
+	"os"
+	"time"
+
+	"github.com/foxcpp/go-sieve"
+	"github.com/foxcpp/go-sieve/interp"
+)
+
+func main() {
+	msgPath := flag.String("eml", "", "msgPath message to process")
+	scriptPath := flag.String("scriptPath", "", "scriptPath to run")
+	envFrom := flag.String("from", "", "envelope from")
+	envTo := flag.String("to", "", "envelope to")
+	flag.Parse()
+
+	msg, err := os.Open(*msgPath)
+	if err != nil {
+		log.Fatalln(err)
+	}
+	defer msg.Close()
+	fileInfo, err := msg.Stat()
+	if err != nil {
+		log.Fatalln(err)
+	}
+	msgHdr, err := textproto.NewReader(bufio.NewReader(msg)).ReadMIMEHeader()
+	if err != nil {
+		log.Fatalln(err)
+	}
+
+	script, err := os.Open(*scriptPath)
+	if err != nil {
+		log.Fatalln(err)
+	}
+	defer script.Close()
+
+	start := time.Now()
+	loadedScript, err := sieve.Load(script, sieve.DefaultOptions())
+	end := time.Now()
+	if err != nil {
+		log.Fatalln(err)
+	}
+	log.Println("script loaded in", end.Sub(start))
+
+	data := interp.NewRuntimeData(loadedScript, interp.Callback{
+		RedirectAllowed: func(ctx context.Context, d *interp.RuntimeData, addr string) (bool, error) {
+			return true, nil
+		},
+		HeaderGet: func(key string) (string, bool, error) {
+			vals, ok := msgHdr[key]
+			if !ok {
+				return "", false, nil
+			}
+			return vals[0], true, nil
+		},
+	})
+	data.MessageSize = int(fileInfo.Size())
+	data.SMTP.From = *envFrom
+	data.SMTP.To = *envTo
+
+	ctx := context.Background()
+	if err := loadedScript.Execute(ctx, data); err != nil {
+		log.Fatalln(err)
+	}
+
+	log.Println("redirect:", data.RedirectAddr)
+	log.Println("fileinfo:", data.Mailboxes)
+	log.Println("keep:", data.ImplicitKeep || data.Keep)
+}

cmd/sieve-run/msg.eml

@@ -0,0 +1,14 @@
+Date: Tue, 1 Apr 1997 09:06:31 -0800 (PST)
+From: [email protected]
+To: [email protected]
+Subject: I have a present for you
+
+Look, I'm sorry about the whole anvil thing, and I really
+didn't mean to try and drop it on you from the top of the
+cliff.  I want to try to make it up to you.  I've got some
+great birdseed over here at my place--top of the line
+stuff--and if you come by, I'll have it all wrapped up
+for you.  I'm really sorry for all the problems I've caused
+for you over the years, but I know we can work this out.
+--
+Wile E. Coyote   "Super Genius"   [email protected]

cmd/sieve-run/msgB.eml

@@ -0,0 +1,13 @@
+From: [email protected]
+Sender: [email protected]
+To: [email protected]
+Date:  Mon, 31 Mar 1997 18:26:10 -0800
+Subject: $$$ YOU, TOO, CAN BE A MILLIONAIRE! $$$
+
+YOU MAY HAVE ALREADY WON TEN MILLION DOLLARS, BUT I DOUBT
+IT!  SO JUST POST THIS TO SIX HUNDRED NEWSGROUPS!  IT WILL
+GUARANTEE THAT YOU GET AT LEAST FIVE RESPONSES WITH MONEY!
+MONEY! MONEY! COLD HARD CASH!  YOU WILL RECEIVE OVER
+$20,000 IN LESS THAN TWO MONTHS!  AND IT'S LEGAL!!!!!!!!!
+!!!!!!!!!!!!!!!!!!111111111!!!!!!!11111111111!!1  JUST
+SEND $5 IN SMALL, UNMARKED BILLS TO THE ADDRESSES BELOW!

cmd/sieve-run/sieve-run

@@ -0,0 +1,39 @@
+    #
+    # Example Sieve Filter
+    # Declare any optional features or extension used by the script
+    #
+    require ["fileinto"];
+
+    #
+    # Handle messages from known mailing lists
+    # Move messages from IETF filter discussion list to filter mailbox
+    #
+    if header :is "Sender" "[email protected]"
+            {
+            fileinto "filter";  # move to "filter" mailbox
+            }
+    #
+    # Keep all messages to or from people in my company
+    #
+    elsif address :DOMAIN :is ["From", "To"] "example.com"
+            {
+            keep;               # keep in "In" mailbox
+            }
+
+    #
+    # Try and catch unsolicited email.  If a message is not to me,
+    # or it contains a subject known to be spam, file it away.
+    #
+    elsif anyof (NOT address :all :contains
+                   ["To", "Cc", "Bcc"] "[email protected]",
+                 header :matches "subject"
+                   ["*make*money*fast*", "*university*dipl*mas*"])
+            {
+            fileinto "spam";   # move to "spam" mailbox
+            }
+    else
+            {
+            # Move all other (non-company) mail to "personal"
+            # mailbox.
+            fileinto "personal";
+            }

cmd/sieve-run/test.sieve

@@ -1 +1,5 @@
-module github.com/foxcpp/go-sieve
+module github.com/foxcpp/go-sieve
+
+go 1.18
+
+require github.com/davecgh/go-spew v1.1.1

go.mod

@@ -0,0 +1,2 @@
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=

go.sum

@@ -0,0 +1,68 @@
+package interp
+
+import (
+	"context"
+	"fmt"
+)
+
+type CmdStop struct{}
+
+func (c CmdStop) Execute(ctx context.Context, d *RuntimeData) error {
+	return ErrStop
+}
+
+type CmdFileInto struct {
+	Mailbox string
+}
+
+func (c CmdFileInto) Execute(ctx context.Context, d *RuntimeData) error {
+	found := false
+	for _, m := range d.Mailboxes {
+		if m == c.Mailbox {
+			found = true
+		}
+	}
+	if found {
+		return nil
+	}
+	d.Mailboxes = append(d.Mailboxes, c.Mailbox)
+	d.ImplicitKeep = false
+	return nil
+}
+
+type CmdRedirect struct {
+	Addr string
+}
+
+func (c CmdRedirect) Execute(ctx context.Context, d *RuntimeData) error {
+	if d.Callback.RedirectAllowed != nil {
+		ok, err := d.Callback.RedirectAllowed(ctx, d, c.Addr)
+		if err != nil {
+			return err
+		}
+		if !ok {
+			return nil
+		}
+	}
+	d.RedirectAddr = append(d.RedirectAddr, c.Addr)
+	d.ImplicitKeep = false
+
+	if len(d.RedirectAddr) > d.Script.opts.MaxRedirects {
+		return fmt.Errorf("too many actions")
+	}
+	return nil
+}
+
+type CmdKeep struct{}
+
+func (c CmdKeep) Execute(_ context.Context, d *RuntimeData) error {
+	d.Keep = true
+	return nil
+}
+
+type CmdDiscard struct{}
+
+func (c CmdDiscard) Execute(_ context.Context, d *RuntimeData) error {
+	d.ImplicitKeep = false
+	return nil
+}

interp/action.go

@@ -0,0 +1,66 @@
+package interp
+
+import (
+	"context"
+)
+
+type CmdIf struct {
+	Test  Test
+	Block []Cmd
+}
+
+func (c CmdIf) Execute(ctx context.Context, d *RuntimeData) error {
+	res, err := c.Test.Check(ctx, d)
+	if err != nil {
+		return err
+	}
+	if res {
+		for _, c := range c.Block {
+			if err := c.Execute(ctx, d); err != nil {
+				return err
+			}
+		}
+	}
+	d.ifResult = res
+	return nil
+}
+
+type CmdElsif struct {
+	Test  Test
+	Block []Cmd
+}
+
+func (c CmdElsif) Execute(ctx context.Context, d *RuntimeData) error {
+	if d.ifResult {
+		return nil
+	}
+	res, err := c.Test.Check(ctx, d)
+	if err != nil {
+		return err
+	}
+	if res {
+		for _, c := range c.Block {
+			if err := c.Execute(ctx, d); err != nil {
+				return err
+			}
+		}
+	}
+	d.ifResult = res
+	return nil
+}
+
+type CmdElse struct {
+	Block []Cmd
+}
+
+func (c CmdElse) Execute(ctx context.Context, d *RuntimeData) error {
+	if d.ifResult {
+		return nil
+	}
+	for _, c := range c.Block {
+		if err := c.Execute(ctx, d); err != nil {
+			return err
+		}
+	}
+	return nil
+}

interp/control.go

@@ -0,0 +1,97 @@
+package interp
+
+import (
+	"strings"
+
+	"github.com/foxcpp/go-sieve/lexer"
+	"github.com/foxcpp/go-sieve/parser"
+)
+
+var supportedExtensions = map[string]struct{}{
+	"fileinto": {},
+	"envelope": {},
+}
+
+var (
+	commands map[string]func(*Script, parser.Cmd) (Cmd, error)
+	tests    map[string]func(*Script, parser.Test) (Test, error)
+)
+
+func init() {
+	// break initialization loop
+
+	commands = map[string]func(*Script, parser.Cmd) (Cmd, error){
+		// RFC 5228 Actions
+		"require": loadRequire,
+		"if":      loadIf,
+		"elsif":   loadElsif,
+		"else":    loadElse,
+		"stop":    loadStop,
+		// RFC 5228 Actions
+		"fileinto": loadFileInto, // fileinto extension
+		"redirect": loadRedirect,
+		"keep":     loadKeep,
+		"discard":  loadDiscard,
+	}
+	tests = map[string]func(*Script, parser.Test) (Test, error){
+		// RFC 5228 Tests
+		"address":  loadAddressTest,
+		"allof":    loadAllOfTest,
+		"anyof":    loadAnyOfTest,
+		"envelope": loadEnvelopeTest, // envelope extension
+		"exists":   loadExistsTest,
+		"false":    loadFalseTest,
+		"true":     loadTrueTest,
+		"header":   loadHeaderTest,
+		"not":      loadNotTest,
+		"size":     loadSizeTest,
+	}
+}
+
+func LoadScript(cmdStream []parser.Cmd, opts *Options) (*Script, error) {
+	s := &Script{
+		opts: opts,
+	}
+
+	loadedCmds, err := LoadBlock(s, cmdStream)
+	if err != nil {
+		return nil, err
+	}
+	s.cmd = loadedCmds
+
+	return s, nil
+}
+
+func LoadBlock(s *Script, cmds []parser.Cmd) ([]Cmd, error) {
+	loaded := make([]Cmd, 0, len(cmds))
+	for _, c := range cmds {
+		cmd, err := LoadCmd(s, c)
+		if err != nil {
+			return nil, err
+		}
+		if cmd == nil {
+			continue
+		}
+		loaded = append(loaded, cmd)
+	}
+	return loaded, nil
+}
+
+func LoadCmd(s *Script, cmd parser.Cmd) (Cmd, error) {
+	cmdName := strings.ToLower(cmd.Id)
+	factory := commands[cmdName]
+	if factory == nil {
+		return nil, lexer.ErrorAt(cmd, "LoadBlock: unsupported command: %v", cmdName)
+	}
+	return factory(s, cmd)
+
+}
+
+func LoadTest(s *Script, t parser.Test) (Test, error) {
+	testName := strings.ToLower(t.Id)
+	factory := tests[testName]
+	if factory == nil {
+		return nil, lexer.ErrorAt(t, "LoadTest: unsupported test: %v", testName)
+	}
+	return factory(s, t)
+}