Initial commit

10 files changed, 544 insertions, 0 deletions

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..567609b
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+build/
diff --git a/build.gradle.kts b/build.gradle.kts
new file mode 100644
index 0000000..1cd365e
--- /dev/null
+++ b/build.gradle.kts
@@ -0,0 +1,20 @@
+plugins {
+    kotlin("jvm") version "1.5.31"
+    application
+}
+
+group = "moe.nea89"
+version = "0.0.0"
+
+repositories {
+    mavenCentral()
+}
+
+application {
+    mainClass.set("Main")
+}
+
+dependencies {
+    implementation(kotlin("stdlib"))
+    implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.5.2")
+}
diff --git a/gradle.properties b/gradle.properties
new file mode 100644
index 0000000..29e08e8
--- /dev/null
+++ b/gradle.properties
@@ -0,0 +1 @@
+kotlin.code.style=official
\ No newline at end of file
diff --git a/gradle/wrapper/gradle-wrapper.jar b/gradle/wrapper/gradle-wrapper.jar
new file mode 100644
index 0000000..7454180
--- /dev/null
+++ b/gradle/wrapper/gradle-wrapper.jar
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
new file mode 100644
index 0000000..69a9715
--- /dev/null
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -0,0 +1,5 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.1-bin.zip
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists
diff --git a/gradlew b/gradlew
new file mode 100755
index 0000000..744e882
--- /dev/null
+++ b/gradlew
@@ -0,0 +1,185 @@
+#!/usr/bin/env sh
+
+#
+# Copyright 2015 the original author or authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+##############################################################################
+##
+##  Gradle start up script for UN*X
+##
+##############################################################################
+
+# Attempt to set APP_HOME
+# Resolve links: $0 may be a link
+PRG="$0"
+# Need this for relative symlinks.
+while [ -h "$PRG" ] ; do
+    ls=`ls -ld "$PRG"`
+    link=`expr "$ls" : '.*-> \(.*\)$'`
+    if expr "$link" : '/.*' > /dev/null; then
+        PRG="$link"
+    else
+        PRG=`dirname "$PRG"`"/$link"
+    fi
+done
+SAVED="`pwd`"
+cd "`dirname \"$PRG\"`/" >/dev/null
+APP_HOME="`pwd -P`"
+cd "$SAVED" >/dev/null
+
+APP_NAME="Gradle"
+APP_BASE_NAME=`basename "$0"`
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD="maximum"
+
+warn () {
+    echo "$*"
+}
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+}
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "`uname`" in
+  CYGWIN* )
+    cygwin=true
+    ;;
+  Darwin* )
+    darwin=true
+    ;;
+  MSYS* | MINGW* )
+    msys=true
+    ;;
+  NONSTOP* )
+    nonstop=true
+    ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+        JAVACMD="$JAVA_HOME/bin/java"
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD="java"
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then
+    MAX_FD_LIMIT=`ulimit -H -n`
+    if [ $? -eq 0 ] ; then
+        if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then
+            MAX_FD="$MAX_FD_LIMIT"
+        fi
+        ulimit -n $MAX_FD
+        if [ $? -ne 0 ] ; then
+            warn "Could not set maximum file descriptor limit: $MAX_FD"
+        fi
+    else
+        warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT"
+    fi
+fi
+
+# For Darwin, add options to specify how the application appears in the dock
+if $darwin; then
+    GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\""
+fi
+
+# For Cygwin or MSYS, switch paths to Windows format before running java
+if [ "$cygwin" = "true" -o "$msys" = "true" ] ; then
+    APP_HOME=`cygpath --path --mixed "$APP_HOME"`
+    CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
+
+    JAVACMD=`cygpath --unix "$JAVACMD"`
+
+    # We build the pattern for arguments to be converted via cygpath
+    ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null`
+    SEP=""
+    for dir in $ROOTDIRSRAW ; do
+        ROOTDIRS="$ROOTDIRS$SEP$dir"
+        SEP="|"
+    done
+    OURCYGPATTERN="(^($ROOTDIRS))"
+    # Add a user-defined pattern to the cygpath arguments
+    if [ "$GRADLE_CYGPATTERN" != "" ] ; then
+        OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)"
+    fi
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    i=0
+    for arg in "$@" ; do
+        CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -`
+        CHECK2=`echo "$arg"|egrep -c "^-"`                                 ### Determine if an option
+
+        if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then                    ### Added a condition
+            eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"`
+        else
+            eval `echo args$i`="\"$arg\""
+        fi
+        i=`expr $i + 1`
+    done
+    case $i in
+        0) set -- ;;
+        1) set -- "$args0" ;;
+        2) set -- "$args0" "$args1" ;;
+        3) set -- "$args0" "$args1" "$args2" ;;
+        4) set -- "$args0" "$args1" "$args2" "$args3" ;;
+        5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
+        6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
+        7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
+        8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
+        9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
+    esac
+fi
+
+# Escape application args
+save () {
+    for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done
+    echo " "
+}
+APP_ARGS=`save "$@"`
+
+# Collect all arguments for the java command, following the shell quoting and substitution rules
+eval set -- $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS "\"-Dorg.gradle.appname=$APP_BASE_NAME\"" -classpath "\"$CLASSPATH\"" org.gradle.wrapper.GradleWrapperMain "$APP_ARGS"
+
+exec "$JAVACMD" "$@"
diff --git a/gradlew.bat b/gradlew.bat
new file mode 100644
index 0000000..107acd3
--- /dev/null
+++ b/gradlew.bat
@@ -0,0 +1,89 @@
+@rem
+@rem Copyright 2015 the original author or authors.
+@rem
+@rem Licensed under the Apache License, Version 2.0 (the "License");
+@rem you may not use this file except in compliance with the License.
+@rem You may obtain a copy of the License at
+@rem
+@rem      https://www.apache.org/licenses/LICENSE-2.0
+@rem
+@rem Unless required by applicable law or agreed to in writing, software
+@rem distributed under the License is distributed on an "AS IS" BASIS,
+@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+@rem See the License for the specific language governing permissions and
+@rem limitations under the License.
+@rem
+
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Resolve any "." and ".." in APP_HOME to make it shorter.
+for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m"
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto execute
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto execute
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %*
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega
diff --git a/settings.gradle.kts b/settings.gradle.kts
new file mode 100644
index 0000000..5d04017
--- /dev/null
+++ b/settings.gradle.kts
@@ -0,0 +1,2 @@
+rootProject.name = "javamailtest"
+
diff --git a/src/main/kotlin/Main.kt b/src/main/kotlin/Main.kt
new file mode 100644
index 0000000..577c3fb
--- /dev/null
+++ b/src/main/kotlin/Main.kt
@@ -0,0 +1,31 @@
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.runBlocking
+import java.net.ServerSocket
+
+object Main {
+
+    @JvmStatic
+    fun main(args: Array<String>) {
+        if (args.size != 1) {
+            System.err.println("Use ./javamailteste run/install")
+        }
+        when (args[0]) {
+            "run" -> runServer(2500)
+        }
+    }
+
+    fun runServer(port: Int) = runBlocking(Dispatchers.Default) {
+        val ss = ServerSocket(port)
+        val jobs = mutableListOf<Job>()
+        println("Starting SMTP socket on port $port")
+        while (true) {
+            val scope = CoroutineScope(Dispatchers.Default)
+            val socket = with(Dispatchers.IO) { ss.accept() }
+            val prot = SMTPReceiveProtocol("nea89.moe", socket.inetAddress)
+            jobs.add(prot.executeAsync(scope, Protocol.IO.FromSocket(socket)))
+            println("jobs: $jobs")
+        }
+    }
+}
diff --git a/src/main/kotlin/SMTPProtocol.kt b/src/main/kotlin/SMTPProtocol.kt
new file mode 100644
index 0000000..2294c88
--- /dev/null
+++ b/src/main/kotlin/SMTPProtocol.kt
@@ -0,0 +1,210 @@
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.launch
+import java.io.InputStream
+import java.io.OutputStream
+import java.net.InetAddress
+import java.net.Socket
+import kotlin.contracts.ExperimentalContracts
+import kotlin.contracts.InvocationKind
+import kotlin.contracts.contract
+
+class Invalidatable {
+    var isInvalid: Boolean = false
+    fun checkValid() {
+        if (isInvalid)
+            throw IllegalStateException("Accessed invalid object")
+    }
+
+    fun invalidate() {
+        isInvalid = true
+    }
+}
+
+abstract class Protocol {
+    interface IO {
+        fun isOpen(): Boolean
+        suspend fun pushBack(data: ByteArray)
+        suspend fun readBytes(into: ByteArray): Int
+        suspend fun send(bytes: ByteArray)
+        suspend fun close()
+        class FromSocket(val socket: Socket) : FromStreams(socket.getInputStream(), socket.getOutputStream()) {
+            override suspend fun close() {
+                super.close()
+                with(Dispatchers.IO) {
+                    socket.close()
+                }
+            }
+        }
+
+        open class FromStreams(val inputStream: InputStream, val outputStream: OutputStream) : IO {
+            private val i = Invalidatable()
+            override fun isOpen(): Boolean =
+                !i.isInvalid
+
+
+            val readBuffer = mutableListOf<ByteArray>()
+            override suspend fun pushBack(data: ByteArray) {
+                i.checkValid()
+                if (data.isEmpty()) return
+                readBuffer.add(0, data)
+            }
+
+            override suspend fun send(bytes: ByteArray) {
+                i.checkValid()
+                with(Dispatchers.IO) {
+                    outputStream.write(bytes)
+                    outputStream.flush()
+                }
+            }
+
+            override suspend fun close() {
+                i.checkValid()
+                i.invalidate()
+                with(Dispatchers.IO) {
+                    inputStream.close()
+                    outputStream.close()
+                }
+            }
+
+            override suspend fun readBytes(into: ByteArray): Int {
+                i.checkValid()
+                val rb = readBuffer.removeFirstOrNull()
+                if (rb != null) {
+                    val w = minOf(rb.size, into.size)
+                    rb.copyInto(into, 0, 0, w)
+                    return w
+                }
+                return with(Dispatchers.IO) {
+                    inputStream.read(into)
+                }
+            }
+        }
+    }
+
+    protected abstract suspend fun IO.execute()
+
+    fun executeAsync(scope: CoroutineScope, io: Protocol.IO): Job {
+        return scope.launch {
+            io.execute()
+        }
+    }
+}
+
+suspend fun Protocol.IO.send(string: String) = send(string.encodeToByteArray())
+suspend fun Protocol.IO.readLine(): String {
+    val y = mutableListOf<String>()
+    while (true) {
+        val buffer = ByteArray(4096)
+        val read = readBytes(buffer)
+        val i = buffer.findCRLF()
+        if (i in 0 until read) {
+            y.add(buffer.copyOfRange(0, i).decodeToString())
+            pushBack(buffer.copyOfRange(i + 2, read))
+            break
+        } else {
+            y.add(buffer.copyOfRange(0, read).decodeToString())
+        }
+    }
+    return y.joinToString("")
+}
+
+private fun ByteArray.findCRLF(): Int {
+    return this.asSequence().zipWithNext().withIndex().firstOrNull { (idx, v) ->
+        (v.first == '\r'.code.toByte()) and (v.second == '\n'.code.toByte())
+    }?.index ?: -1
+}
+
+suspend fun Protocol.IO.pushBack(string: String) = pushBack(string.encodeToByteArray())
+suspend fun Protocol.IO.lookahead(string: String): Boolean = lookahead(string.encodeToByteArray())
+suspend fun Protocol.IO.lookahead(bytes: ByteArray): Boolean {
+    val buffer = ByteArray(bytes.size)
+    val read = readBytes(buffer)
+    if (read != bytes.size || !buffer.contentEquals(bytes)) {
+        pushBack(buffer.copyOf(read))
+        return false
+    }
+    return true
+}
+
+
+@OptIn(ExperimentalContracts::class)
+class SMTPReceiveProtocol(val localHost: String, val inetAddress: InetAddress) : Protocol() {
+
+    class Commands(val line: String, private val io: IO) : IO by io {
+        var matched = false
+
+
+        suspend inline fun command(vararg name: String, block: IO.(String) -> Unit) {
+            contract { callsInPlace(block, InvocationKind.AT_MOST_ONCE) }
+            for (n in name) commandOnce(n, block)
+        }
+
+        suspend inline fun commandOnce(name: String, block: IO.(String) -> Unit) {
+            contract { callsInPlace(block, InvocationKind.AT_MOST_ONCE) }
+            if (matched) return
+            if (!line.startsWith(name)) return
+            matched = true
+            block(line.substring(name.length).trimStart())
+        }
+
+        suspend inline fun otherwise(block: IO.(String) -> Unit) {
+            contract { callsInPlace(block, InvocationKind.AT_MOST_ONCE) }
+            if (matched) return
+            matched = true
+            block(line)
+        }
+    }
+
+    suspend inline fun IO.commands(line: String, block: Commands.() -> Unit) {
+        contract { callsInPlace(block, InvocationKind.EXACTLY_ONCE) }
+        Commands(line, this).block()
+    }
+
+    override suspend fun IO.execute() {
+        send("220 $localHost\r\n")
+        var isHelod = false
+        var receipient: String? = null
+        var sender: String? = null
+        var text: String? = null
+        while (isOpen()) {
+            commands(readLine()) {
+                println(line)
+                command("HELO", "EHLO") {
+                    send("250 Hello $it, how are you on this fine day?\r\n")
+                    isHelod = true
+                }
+                command("MAIL FROM:") {
+                    send("250 Sender ok\r\n")
+                    sender = it
+                }
+                command("RCPT TO:") {
+                    send("250 Receipient ok\r\n")
+                    receipient = it
+                }
+                command("DATA") {
+                    send("354 Enter mail, end with \".\" on a line by itself\r\n")
+                    text = ""
+                    while (true) {
+                        val tmp = readLine()
+                        if (tmp == ".") break
+                        text += tmp + "\r\n"
+                    }
+                    send("250 Message accepted for delivery\r\n")
+                }
+                command("QUIT") {
+                    send("221 $localHost closing connection\r\n")
+                    close()
+                }
+                otherwise {
+                    send("XXX ERROR UNKNOWN CODE $it\r\n")
+                }
+            }
+        }
+        println("IsHelod: $isHelod")
+        println("From: $sender")
+        println("To: $receipient")
+        println("\n$text")
+    }
+}