gophi/gophor.go
kim (grufwub) c9ffda1ae5 version bump :)
Signed-off-by: kim (grufwub) <grufwub@gmail.com>
2020-05-17 09:56:22 +01:00

242 lines
10 KiB
Go

package main
import (
"os"
"log"
"strconv"
"syscall"
"os/signal"
"flag"
"time"
)
const (
GophorVersion = "1.0-beta"
)
var (
Config *ServerConfig
)
func main() {
/* Setup the entire server, getting slice of listeners in return */
listeners := setupServer()
/* Handle signals so we can _actually_ shutdowm */
signals := make(chan os.Signal)
signal.Notify(signals, syscall.SIGINT, syscall.SIGTERM, syscall.SIGKILL)
/* Start accepting connections on any supplied listeners */
for _, l := range listeners {
go func() {
Config.SysLog.Info("", "Listening on: gopher://%s:%s\n", l.Host.Name(), l.Host.RealPort())
for {
worker, err := l.Accept()
if err != nil {
Config.SysLog.Error("", "Error accepting connection: %s\n", err.Error())
continue
}
go worker.Serve()
}
}()
}
/* When OS signal received, we close-up */
sig := <-signals
Config.SysLog.Info("", "Signal received: %v. Shutting down...\n", sig)
os.Exit(0)
}
func setupServer() []*GophorListener {
/* First we setup all the flags and parse them... */
/* Base server settings */
serverRoot := flag.String("root", "/var/gopher", "Change server root directory.")
serverBindAddr := flag.String("bind-addr", "127.0.0.1", "Change server socket bind address")
serverPort := flag.Int("port", 70, "Change server bind port.")
serverFwdPort := flag.Int("fwd-port", 0, "Change port used in '$port' replacement strings (useful if you're port forwarding).")
serverHostname := flag.String("hostname", "127.0.0.1", "Change server hostname (FQDN).")
/* Logging settings */
systemLogPath := flag.String("system-log", "", "Change server system log file (blank outputs to stderr).")
accessLogPath := flag.String("access-log", "", "Change server access log file (blank outputs to stderr).")
logOutput := flag.String("log-output", "stderr", "Change server log file handling (disable|stderr|file)")
logOpts := flag.String("log-opts", "timestamp,ip", "Comma-separated list of log options (timestamp|ip)")
/* File system */
fileMonitorFreq := flag.Duration("file-monitor-freq", time.Second*60, "Change file monitor frequency.")
/* Cache settings */
cacheSize := flag.Int("cache-size", 50, "Change file cache size, measured in file count.")
cacheFileSizeMax := flag.Float64("cache-file-max", 0.5, "Change maximum file size to be cached (in megabytes).")
cacheDisabled := flag.Bool("disable-cache", false, "Disable file caching.")
/* Content settings */
pageWidth := flag.Int("page-width", 80, "Change page width used when formatting output.")
// charSet := flag.String("charset", "", "Change default output charset.")
charSet := "utf-8"
footerText := flag.String("footer", " Gophor, a Gopher server in Go.", "Change gophermap footer text (Unix new-line separated lines).")
footerSeparator := flag.Bool("no-footer-separator", false, "Disable footer line separator.")
/* Regex */
restrictedFiles := flag.String("restrict-files", "", "New-line separated list of regex statements restricting accessible files.")
fileRemaps := flag.String("file-remap", "", "New-line separated list of file remappings of format: /virtual/relative/path -> /actual/relative/path")
/* User supplied caps.txt information */
serverDescription := flag.String("description", "Gophor, a Gopher server in Go.", "Change server description in generated caps.txt.")
serverAdmin := flag.String("admin-email", "", "Change admin email in generated caps.txt.")
serverGeoloc := flag.String("geoloc", "", "Change server gelocation string in generated caps.txt.")
/* Exec settings */
disableCgi := flag.Bool("disable-cgi", false, "Disable CGI and all executable support.")
httpCompatCgi := flag.Bool("http-compat-cgi", false, "Enable HTTP CGI script compatibility (will strip HTTP headers).")
httpHeaderBuf := flag.Int("http-header-buf", 4096, "Change max CGI read count to look for and strip HTTP headers before sending raw (bytes).")
safeExecPath := flag.String("safe-path", "/usr/bin:/bin", "Set safe PATH variable to be used when executing CGI scripts, gophermaps and inline shell commands.")
maxExecRunTime := flag.Duration("max-exec-time", time.Second*3, "Change max executable CGI, gophermap and inline shell command runtime.")
/* Buffer sizes */
socketWriteBuf := flag.Int("socket-write-buf", 4096, "Change socket write buffer size (bytes).")
socketReadBuf := flag.Int("socket-read-buf", 256, "Change socket read buffer size (bytes).")
socketReadMax := flag.Int("socket-read-max", 8, "Change socket read count max (integer multiplier socket-read-buf-max)")
fileReadBuf := flag.Int("file-read-buf", 4096, "Change file read buffer size (bytes).")
/* Socket deadliens */
socketReadTimeout := flag.Duration("socket-read-timeout", time.Second*5, "Change socket read deadline (timeout).")
socketWriteTimeout := flag.Duration("socket-write-timeout", time.Second*30, "Change socket write deadline (timeout).")
/* Version string */
version := flag.Bool("version", false, "Print version information.")
/* Parse parse parse!! */
flag.Parse()
if *version {
printVersionExit()
}
/* Setup the server configuration instance and enter as much as we can right now */
Config = new(ServerConfig)
/* Set misc content settings */
Config.PageWidth = *pageWidth
/* Setup various buffer sizes */
Config.SocketWriteBufSize = *socketWriteBuf
Config.SocketReadBufSize = *socketReadBuf
Config.SocketReadMax = *socketReadBuf * *socketReadMax
Config.FileReadBufSize = *fileReadBuf
/* Setup socket deadlines */
Config.SocketReadDeadline = *socketReadTimeout
Config.SocketWriteDeadline = *socketWriteTimeout
/* Have to be set AFTER page width variable set */
Config.FooterText = formatGophermapFooter(*footerText, !*footerSeparator)
/* Setup Gophor logging system */
Config.SysLog, Config.AccLog = setupLoggers(*logOutput, *logOpts, *systemLogPath, *accessLogPath)
/* Set CGI support status */
if *disableCgi {
Config.SysLog.Info("", "CGI support disabled\n")
Config.CgiEnabled = false
} else {
/* Enable CGI */
Config.SysLog.Info("", "CGI support enabled\n")
Config.CgiEnabled = true
if *httpCompatCgi {
Config.SysLog.Info("", "Enabling HTTP CGI script compatibility\n")
executeCgi = executeCgiStripHttp
/* Specific to CGI buffer */
Config.SysLog.Info("", "Max CGI HTTP header read-ahead: %d bytes\n", *httpHeaderBuf)
Config.SkipPrefixBufSize = *httpHeaderBuf
} else {
executeCgi = executeCgiNoHttp
}
/* Set safe executable path and setup environments */
Config.SysLog.Info("", "Setting safe executable path: %s\n", *safeExecPath)
Config.Env = setupExecEnviron(*safeExecPath)
Config.CgiEnv = setupInitialCgiEnviron(*safeExecPath, charSet)
/* Set executable watchdog */
Config.SysLog.Info("", "Max executable time: %s\n", *maxExecRunTime)
Config.MaxExecRunTime = *maxExecRunTime
}
/* If running as root, get ready to drop privileges */
if syscall.Getuid() == 0 || syscall.Getgid() == 0 {
log.Fatalf("", "Gophor does not support running as root!\n")
}
/* Enter server dir */
enterServerDir(*serverRoot)
Config.SysLog.Info("", "Entered server directory: %s\n", *serverRoot)
/* Setup listeners */
listeners := make([]*GophorListener, 0)
/* If requested, setup unencrypted listener */
if *serverPort != 0 {
/* If no forward port set, just use regular */
if *serverFwdPort == 0 {
*serverFwdPort = *serverPort
}
l, err := BeginGophorListen(*serverBindAddr, *serverHostname, strconv.Itoa(*serverPort), strconv.Itoa(*serverFwdPort), *serverRoot)
if err != nil {
log.Fatalf("Error setting up (unencrypted) listener: %s\n", err.Error())
}
listeners = append(listeners, l)
} else {
log.Fatalf("No valid port to listen on\n")
}
/* Setup file cache */
Config.FileSystem = new(FileSystem)
/* Check if cache requested disabled */
if !*cacheDisabled {
/* Init file cache */
Config.FileSystem.Init(*cacheSize, *cacheFileSizeMax)
/* Before file monitor or any kind of new goroutines started,
* check if we need to cache generated policy files
*/
cachePolicyFiles(*serverRoot, *serverDescription, *serverAdmin, *serverGeoloc)
/* Start file cache freshness checker */
startFileMonitor(*fileMonitorFreq)
Config.SysLog.Info("", "File caching enabled with: maxcount=%d maxsize=%.3fMB checkfreq=%s\n", *cacheSize, *cacheFileSizeMax, *fileMonitorFreq)
} else {
/* File caching disabled, init with zero max size so nothing gets cached */
Config.FileSystem.Init(2, 0)
Config.SysLog.Info("", "File caching disabled\n")
/* Safe to cache policy files now */
cachePolicyFiles(*serverRoot, *serverDescription, *serverAdmin, *serverGeoloc)
}
/* Setup file restrictions and remappings */
Config.FileSystem.Restricted = compileUserRestrictedRegex(*restrictedFiles)
Config.FileSystem.Remaps = compileUserRemapRegex(*fileRemaps)
/* Precompile some helpful regex */
Config.RgxGophermap = compileGophermapCheckRegex()
Config.RgxCgiBin = compileCgiBinCheckRegex()
/* Return the created listeners slice :) */
return listeners
}
func enterServerDir(path string) {
err := syscall.Chdir(path)
if err != nil {
log.Fatalf("Error changing dir to server root %s: %s\n", path, err.Error())
}
}