user: fix #29 ubuntu21.10 error :connect symbol cant found

user/config_openssl.go

@@ -5,6 +5,9 @@ Copyright © 2022 CFC4N <cfc4n.cs@gmail.com>
 package user
 
 import (
+	"debug/elf"
+	"errors"
+	"fmt"
 	"os"
 	"path/filepath"
 	"strings"
@@ -26,14 +29,15 @@ func NewOpensslConfig() *OpensslConfig {
 
 func (this *OpensslConfig) Check() error {
 
+	var checkedOpenssl, checkedConnect bool
 	// 如果readline 配置，且存在，则直接返回。
 	if this.Openssl != "" || len(strings.TrimSpace(this.Openssl)) > 0 {
 		_, e := os.Stat(this.Openssl)
 		if e != nil {
 			return e
 		}
 		this.elfType = ELF_TYPE_SO
-		return nil
+		checkedOpenssl = true
 	}
 
 	//如果配置 Curlpath的地址，判断文件是否存在，不存在则直接返回
@@ -47,6 +51,32 @@ func (this *OpensslConfig) Check() error {
 		this.Curlpath = "/usr/bin/curl"
 	}
 
+	if this.Pthread != "" || len(strings.TrimSpace(this.Pthread)) > 0 {
+		_, e := os.Stat(this.Pthread)
+		if e != nil {
+			return e
+		}
+		checkedConnect = true
+	}
+
+	if checkedConnect && checkedOpenssl {
+		return nil
+	}
+
+	if !checkedOpenssl {
+		e := this.checkOpenssl()
+		if e != nil {
+			return e
+		}
+	}
+
+	if !checkedConnect {
+		return this.checkConnect()
+	}
+	return nil
+}
+
+func (this *OpensslConfig) checkOpenssl() error {
 	soPath, e := getDynPathByElf(this.Curlpath, "libssl.so")
 	if e != nil {
 		//this.logger.Printf("get bash:%s dynamic library error:%v.\n", bash, e)
@@ -65,22 +95,64 @@ func (this *OpensslConfig) Check() error {
 		this.Openssl = soPath
 		this.elfType = ELF_TYPE_SO
 	}
+	return nil
+}
 
-	// find /lib/x86_64-linux-gnu/libpthread.so.0 path
-	pthreadSoPath, e := getDynPathByElf(this.Curlpath, "libpthread.so")
-	if e != nil {
-		_, e = os.Stat(X86_BINARY_PREFIX)
-		prefix := X86_BINARY_PREFIX
+func (this *OpensslConfig) checkConnect() error {
+	var sharedObjects = []string{
+		"libpthread.so.0", // ubuntu 21.04 server
+		"libc.so.6",       // ubuntu 21.10 server
+	}
+
+	var funcName = ""
+	var found bool
+	for _, so := range sharedObjects {
+		pthreadSoPath, e := getDynPathByElf(this.Curlpath, so)
 		if e != nil {
-			prefix = OTHERS_BINARY_PREFIX
+			_, e = os.Stat(X86_BINARY_PREFIX)
+			prefix := X86_BINARY_PREFIX
+			if e != nil {
+				prefix = OTHERS_BINARY_PREFIX
+			}
+			this.Pthread = filepath.Join(prefix, so)
+			_, e = os.Stat(this.Pthread)
+			if e != nil {
+				return e
+			}
+		} else {
+			this.Pthread = pthreadSoPath
 		}
-		this.Pthread = filepath.Join(prefix, "libpthread.so.0")
-		_, e = os.Stat(this.Pthread)
+
+		_elf, e := elf.Open(this.Pthread)
 		if e != nil {
 			return e
 		}
-	} else {
-		this.Pthread = pthreadSoPath
+
+		dynamicSymbols, err := _elf.DynamicSymbols()
+		if err != nil {
+			return err
+		}
+
+		//
+		for _, sym := range dynamicSymbols {
+			if sym.Name != "connect" {
+				continue
+			}
+			//fmt.Printf("\tsize:%d,  name:%s,  offset:%d\n", sym.Size, sym.Name, 0)
+			funcName = sym.Name
+			found = true
+			break
+		}
+
+		// if found
+		if found && funcName != "" {
+			break
+		}
+	}
+
+	//如果没找到，则报错。
+	if !found || funcName == "" {
+		return errors.New(fmt.Sprintf("cant found 'connect' function to hook in files::%v", sharedObjects))
 	}
 	return nil
 }