reuse LDAP connection

Signed-off-by: Jörn Friedrich Dreyer <[email protected]>

Author: butonic

go.mod

@@ -10,7 +10,7 @@ require (
 	github.com/deckarep/golang-set v1.8.0
 	github.com/gabriel-vasile/mimetype v1.4.1
 	github.com/ghodss/yaml v1.0.0
-	github.com/go-ldap/ldap/v3 v3.4.2
+	github.com/go-ldap/ldap/v3 v3.4.4
 	github.com/gofrs/uuid v4.2.0+incompatible
 	github.com/golang-jwt/jwt/v4 v4.4.3
 	github.com/google/go-querystring v1.1.0
@@ -26,7 +26,7 @@ require (
 	github.com/russellhaering/goxmldsig v1.1.1
 	github.com/sirupsen/logrus v1.9.0
 	github.com/spf13/cobra v1.5.0
-	golang.org/x/crypto v0.0.0-20220321153916-2c7772ba3064
+	golang.org/x/crypto v0.0.0-20220622213112-05595931fe9d
 	golang.org/x/net v0.8.0
 	golang.org/x/oauth2 v0.0.0-20220223155221-ee480838109b
 	golang.org/x/time v0.0.0-20220224211638-0e9765cccd65
@@ -37,11 +37,11 @@ require (
 )
 
 require (
-	github.com/Azure/go-ntlmssp v0.0.0-20200615164410-66371956d46c // indirect
+	github.com/Azure/go-ntlmssp v0.0.0-20220621081337-cb9428e4ac1e // indirect
 	github.com/beorn7/perks v1.0.1 // indirect
 	github.com/cespare/xxhash/v2 v2.1.2 // indirect
 	github.com/desertbit/timer v0.0.0-20180107155436-c41aec40b27f // indirect
-	github.com/go-asn1-ber/asn1-ber v1.5.3 // indirect
+	github.com/go-asn1-ber/asn1-ber v1.5.4 // indirect
 	github.com/golang/protobuf v1.5.2 // indirect
 	github.com/inconshreveable/mousetrap v1.0.0 // indirect
 	github.com/jonboulle/clockwork v0.2.2 // indirect

go.sum

@@ -31,8 +31,8 @@ cloud.google.com/go/storage v1.6.0/go.mod h1:N7U0C8pVQ/+NIKOBQyamJIeKQKkZ+mxpohl
 cloud.google.com/go/storage v1.8.0/go.mod h1:Wv1Oy7z6Yz3DshWRJFhqM/UCfaWIRTdp0RXyy7KQOVs=
 cloud.google.com/go/storage v1.10.0/go.mod h1:FLPqc6j+Ki4BU591ie1oL6qBQGu2Bl/tZ9ullr3+Kg0=
 dmitri.shuralyov.com/gpu/mtl v0.0.0-20190408044501-666a987793e9/go.mod h1:H6x//7gZCb22OMCxBHrMx7a5I7Hp++hsVxbQ4BYO7hU=
-github.com/Azure/go-ntlmssp v0.0.0-20200615164410-66371956d46c h1:/IBSNwUN8+eKzUzbJPqhK839ygXJ82sde8x3ogr6R28=
-github.com/Azure/go-ntlmssp v0.0.0-20200615164410-66371956d46c/go.mod h1:chxPXzSsl7ZWRAuOIE23GDNzjWuZquvFlgA8xmpunjU=
+github.com/Azure/go-ntlmssp v0.0.0-20220621081337-cb9428e4ac1e h1:NeAW1fUYUEWhft7pkxDf6WoUvEZJ/uOKsvtpjLnn8MU=
+github.com/Azure/go-ntlmssp v0.0.0-20220621081337-cb9428e4ac1e/go.mod h1:chxPXzSsl7ZWRAuOIE23GDNzjWuZquvFlgA8xmpunjU=
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
 github.com/BurntSushi/xgb v0.0.0-20160522181843-27f122750802/go.mod h1:IVnqGOEym/WlBOVXweHU+Q+/VP0lqqI8lqeDx9IjBqo=
 github.com/alecthomas/template v0.0.0-20160405071501-a0175ee3bccc/go.mod h1:LOuyumcjzFXgccqObfd/Ljyb9UuFJ6TxHnclSeseNhc=
@@ -79,18 +79,17 @@ github.com/gabriel-vasile/mimetype v1.4.1 h1:TRWk7se+TOjCYgRth7+1/OYLNiRNIotknkF
 github.com/gabriel-vasile/mimetype v1.4.1/go.mod h1:05Vi0w3Y9c/lNvJOdmIwvrrAhX3rYhfQQCaf9VJcv7M=
 github.com/ghodss/yaml v1.0.0 h1:wQHKEahhL6wmXdzwWG11gIVCkOv05bNOh+Rxn0yngAk=
 github.com/ghodss/yaml v1.0.0/go.mod h1:4dBDuWmgqj2HViK6kFavaiC9ZROes6MMH2rRYeMEF04=
-github.com/go-asn1-ber/asn1-ber v1.5.1/go.mod h1:hEBeB/ic+5LoWskz+yKT7vGhhPYkProFKoKdwZRWMe0=
-github.com/go-asn1-ber/asn1-ber v1.5.3 h1:u7utq56RUFiynqUzgVMFDymapcOtQ/MZkh3H4QYkxag=
-github.com/go-asn1-ber/asn1-ber v1.5.3/go.mod h1:hEBeB/ic+5LoWskz+yKT7vGhhPYkProFKoKdwZRWMe0=
+github.com/go-asn1-ber/asn1-ber v1.5.4 h1:vXT6d/FNDiELJnLb6hGNa309LMsrCoYFvpwHDF0+Y1A=
+github.com/go-asn1-ber/asn1-ber v1.5.4/go.mod h1:hEBeB/ic+5LoWskz+yKT7vGhhPYkProFKoKdwZRWMe0=
 github.com/go-gl/glfw v0.0.0-20190409004039-e6da0acd62b1/go.mod h1:vR7hzQXu2zJy9AVAgeJqvqgH9Q5CA+iKCZ2gyEVpxRU=
 github.com/go-gl/glfw/v3.3/glfw v0.0.0-20191125211704-12ad95a8df72/go.mod h1:tQ2UAYgL5IevRw8kRxooKSPJfGvJ9fJQFa0TUsXzTg8=
 github.com/go-gl/glfw/v3.3/glfw v0.0.0-20200222043503-6f7a984d4dc4/go.mod h1:tQ2UAYgL5IevRw8kRxooKSPJfGvJ9fJQFa0TUsXzTg8=
 github.com/go-kit/kit v0.8.0/go.mod h1:xBxKIO96dXMWWy0MnWVtmwkA9/13aqxPnvrjFYMA2as=
 github.com/go-kit/kit v0.9.0/go.mod h1:xBxKIO96dXMWWy0MnWVtmwkA9/13aqxPnvrjFYMA2as=
 github.com/go-kit/log v0.1.0/go.mod h1:zbhenjAZHb184qTLMA9ZjW7ThYL0H2mk7Q6pNt4vbaY=
 github.com/go-kit/log v0.2.0/go.mod h1:NwTd00d/i8cPZ3xOwwiv2PO5MOcx78fFErGNcVmBjv0=
-github.com/go-ldap/ldap/v3 v3.4.2 h1:zFZKcXKLqZpFMrMQGHeHWKXbDTdNCmhGY9AK41zPh+8=
-github.com/go-ldap/ldap/v3 v3.4.2/go.mod h1:iYS1MdmrmceOJ1QOTnRXrIs7i3kloqtmGQjRvjKpyMg=
+github.com/go-ldap/ldap/v3 v3.4.4 h1:qPjipEpt+qDa6SI/h1fzuGWoRUY+qqQ9sOZq67/PYUs=
+github.com/go-ldap/ldap/v3 v3.4.4/go.mod h1:fe1MsuN5eJJ1FeLT/LEBVdWfNWKh459R7aXgXtJC+aI=
 github.com/go-logfmt/logfmt v0.3.0/go.mod h1:Qt1PoO58o5twSAckw1HlFXLmHsOX5/0LbT9GBnD5lWE=
 github.com/go-logfmt/logfmt v0.4.0/go.mod h1:3RMwSq7FuexP4Kalkev3ejPJsZTpXXBr9+V4qmtdjCk=
 github.com/go-logfmt/logfmt v0.5.0/go.mod h1:wCYkCAKZfumFQihp8CzCvQ3paCTfi41vtzG1KdI/P7A=
@@ -282,8 +281,9 @@ github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXf
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
 github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
-github.com/stretchr/testify v1.7.0 h1:nwc3DEeHmmLAfoZucVR881uASk0Mfjw8xYJ99tb5CcY=
 github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/stretchr/testify v1.7.2 h1:4jaiDzPyXQvSd7D0EjG45355tLlV3VOECpq10pLC+8s=
+github.com/stretchr/testify v1.7.2/go.mod h1:R6va5+xMeoiuVRoj+gSkQ7d3FALtqAAGI1FQKckRals=
 github.com/yuin/goldmark v1.1.25/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
 github.com/yuin/goldmark v1.1.27/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
 github.com/yuin/goldmark v1.1.32/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
@@ -298,11 +298,10 @@ golang.org/x/crypto v0.0.0-20190510104115-cbcb75029529/go.mod h1:yigFU9vqHzYiE8U
 golang.org/x/crypto v0.0.0-20190605123033-f99c8df09eb5/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/crypto v0.0.0-20191128160524-b544559bb6d1/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
-golang.org/x/crypto v0.0.0-20200604202706-70a84ac30bf9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/crypto v0.0.0-20220128200615-198e4374d7ed/go.mod h1:IxCIyHEi3zRg3s0A5j5BB6A9Jmi73HwBIUl50j+osU4=
-golang.org/x/crypto v0.0.0-20220321153916-2c7772ba3064 h1:S25/rfnfsMVgORT4/J61MJ7rdyseOZOyvLIrZEZ7s6s=
-golang.org/x/crypto v0.0.0-20220321153916-2c7772ba3064/go.mod h1:IxCIyHEi3zRg3s0A5j5BB6A9Jmi73HwBIUl50j+osU4=
+golang.org/x/crypto v0.0.0-20220622213112-05595931fe9d h1:sK3txAijHtOK88l68nt020reeT1ZdKLIYetKl95FzVY=
+golang.org/x/crypto v0.0.0-20220622213112-05595931fe9d/go.mod h1:IxCIyHEi3zRg3s0A5j5BB6A9Jmi73HwBIUl50j+osU4=
 golang.org/x/exp v0.0.0-20190121172915-509febef88a4/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
 golang.org/x/exp v0.0.0-20190306152737-a1d7652674e8/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
 golang.org/x/exp v0.0.0-20190510132918-efd6b22b2522/go.mod h1:ZjyILWgesfNpC6sMxTJOJm9Kp84zZh5NQWvqDGG3Qr8=
@@ -584,8 +583,9 @@ gopkg.in/yaml.v2 v2.3.0/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.4.0 h1:D8xgwECY7CYvx+Y2n4sBz93Jn9JRvxdiyyo8CTfuKaY=
 gopkg.in/yaml.v2 v2.4.0/go.mod h1:RDklbk79AGWmwhnvt/jBztapEOGDOx6ZbXqjP6csGnQ=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
-gopkg.in/yaml.v3 v3.0.0-20210107192922-496545a6307b h1:h8qDotaEPuJATrMmW04NCwg7v22aHH28wwpauUhK9Oo=
 gopkg.in/yaml.v3 v3.0.0-20210107192922-496545a6307b/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gotest.tools v2.2.0+incompatible h1:VsBPFP1AI068pPrMxtb/S8Zkgf9xEmTLJjfM+P5UIEo=
 gotest.tools v2.2.0+incompatible/go.mod h1:DsYFclhRJ6vuDpmuTbkuFWG+y2sxOXAzmJt81HFBacw=
 honnef.co/go/tools v0.0.0-20190102054323-c2f93a96b099/go.mod h1:rf3lG4BRIbNafJWhAfAdb/ePZxsR/4RtNHQocxwk9r4=

identifier/backends/ldap/ldap.go

@@ -26,6 +26,7 @@ import (
 	"net/url"
 	"strconv"
 	"strings"
+	"sync"
 	"time"
 
 	"github.com/go-ldap/ldap/v3"
@@ -71,6 +72,9 @@ type LDAPIdentifierBackend struct {
 
 	timeout int
 	limiter *rate.Limiter
+
+	mutex sync.Mutex
+	conn  *ldap.Conn
 }
 
 type ldapAttributeMapping map[string]string
@@ -370,9 +374,8 @@ func (b *LDAPIdentifierBackend) Logon(ctx context.Context, audience, username, p
 
 	l, err := b.connect(ctx)
 	if err != nil {
-		return false, nil, nil, nil, fmt.Errorf("ldap identifier backend logon connect error: %v", err)
+		return false, nil, nil, nil, fmt.Errorf("ldap identifier backend logon global connect error: %v", err)
 	}
-	defer l.Close()
 
 	// Search for the given username.
 	entry, err := b.searchUsername(l, username, b.attributeMapping.attributes())
@@ -387,8 +390,15 @@ func (b *LDAPIdentifierBackend) Logon(ctx context.Context, audience, username, p
 		return false, nil, nil, nil, fmt.Errorf("ldap identifier backend logon search returned wrong user")
 	}
 
-	// Bind as the user to verify the password.
-	err = l.Bind(entry.DN, password)
+	// Use a temporary connection for the user Bind to verify the password.
+	ul, err := b.createConnection(ctx, entry.DN, password)
+	if err != nil {
+		return false, nil, nil, nil, fmt.Errorf("ldap identifier backend logon user connect error: %v", err)
+	}
+	// Always close the temporary connection
+	defer ul.Close()
+
+	err = ul.Bind(entry.DN, password)
 	switch {
 	case ldap.IsErrorWithCode(err, ldap.LDAPResultInvalidCredentials):
 		return false, nil, nil, nil, nil
@@ -431,7 +441,6 @@ func (b *LDAPIdentifierBackend) ResolveUserByUsername(ctx context.Context, usern
 	if err != nil {
 		return nil, fmt.Errorf("ldap identifier backend resolve connect error: %v", err)
 	}
-	defer l.Close()
 
 	// Search for the given username.
 	entry, err := b.searchUsername(l, username, b.attributeMapping.attributes())
@@ -464,7 +473,6 @@ func (b *LDAPIdentifierBackend) GetUser(ctx context.Context, entryID string, ses
 	if err != nil {
 		return nil, fmt.Errorf("ldap identifier backend get user connect error: %v", err)
 	}
-	defer l.Close()
 
 	entry, err := b.getUser(l, entryID, b.attributeMapping.attributes())
 	if err != nil {
@@ -517,7 +525,7 @@ func (b *LDAPIdentifierBackend) Name() string {
 	return ldapIdentifierBackendName
 }
 
-func (b *LDAPIdentifierBackend) connect(parentCtx context.Context) (*ldap.Conn, error) {
+func (b *LDAPIdentifierBackend) createConnection(parentCtx context.Context, bindDN, bindPassword string) (*ldap.Conn, error) {
 	// A timeout for waiting for a limiter slot. The timeout also includes the
 	// time to connect to the LDAP server which as a consequence means that both
 	// getting a free slot and establishing the connection are one timeout.
@@ -550,9 +558,8 @@ func (b *LDAPIdentifierBackend) connect(parentCtx context.Context) (*ldap.Conn,
 
 	l.Start()
 
-	// Bind with general user (which is preferably read only).
-	if b.bindDN != "" {
-		err = l.Bind(b.bindDN, b.bindPassword)
+	if bindDN != "" {
+		err = l.Bind(bindDN, bindPassword)
 		if err != nil {
 			return nil, err
 		}
@@ -561,6 +568,20 @@ func (b *LDAPIdentifierBackend) connect(parentCtx context.Context) (*ldap.Conn,
 	return l, nil
 }
 
+// connect establishes a global connection that is used for all requests except the user Bind to check the password in the Logon call.
+func (b *LDAPIdentifierBackend) connect(parentCtx context.Context) (*ldap.Conn, error) {
+	b.mutex.Lock()
+	defer b.mutex.Unlock()
+
+	if b.conn != nil && !b.conn.IsClosing() {
+		return b.conn, nil
+	}
+	var err error
+	b.conn, err = b.createConnection(parentCtx, b.bindDN, b.bindPassword)
+
+	return b.conn, err
+}
+
 func (b *LDAPIdentifierBackend) searchUsername(l *ldap.Conn, username string, attributes []string) (*ldap.Entry, error) {
 	base, filter := b.baseAndSearchFilterFromUsername(username)
 	// Search for the given username.