Postgres: Add support for scram sha 256 authentication (#18397)

Allow datasource connection to postgres with password "scram-sha-256" 
authentification.

Fixes #14662

go.mod

@@ -44,7 +44,7 @@ require (
 	github.com/k0kubun/colorstring v0.0.0-20150214042306-9440f1994b88 // indirect
 	github.com/klauspost/compress v1.4.1 // indirect
 	github.com/klauspost/cpuid v1.2.0 // indirect
-	github.com/lib/pq v1.0.0
+	github.com/lib/pq v1.2.0
 	github.com/mattn/go-colorable v0.1.1 // indirect
 	github.com/mattn/go-isatty v0.0.7
 	github.com/mattn/go-sqlite3 v1.10.0
@@ -52,7 +52,7 @@ require (
 	github.com/onsi/gomega v1.5.0 // indirect
 	github.com/opentracing/opentracing-go v1.1.0
 	github.com/patrickmn/go-cache v2.1.0+incompatible
-	github.com/pkg/errors v0.8.1
+	github.com/pkg/errors v0.8.1 // indirect
 	github.com/prometheus/client_golang v0.9.2
 	github.com/prometheus/client_model v0.0.0-20190129233127-fd36f4220a90
 	github.com/prometheus/common v0.2.0

go.sum

@@ -132,6 +132,8 @@ github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/lib/pq v1.0.0 h1:X5PMW56eZitiTeO7tKzZxFCSpbFZJtkMMooicw2us9A=
 github.com/lib/pq v1.0.0/go.mod h1:5WUZQaWbwv1U+lTReE5YruASi9Al49XbQIvNi/34Woo=
+github.com/lib/pq v1.2.0 h1:LXpIM/LZ5xGFhOpXAQUIMM1HdyqzVYM13zNdjCEEcA0=
+github.com/lib/pq v1.2.0/go.mod h1:5WUZQaWbwv1U+lTReE5YruASi9Al49XbQIvNi/34Woo=
 github.com/mattn/go-colorable v0.1.1 h1:G1f5SKeVxmagw/IyvzvtZE4Gybcc4Tr1tf7I8z0XgOg=
 github.com/mattn/go-colorable v0.1.1/go.mod h1:FuOcm+DKB9mbwrcAfNl7/TZVBZ6rcnceauSikq3lYCQ=
 github.com/mattn/go-isatty v0.0.5/go.mod h1:Iq45c/XA43vh69/j3iqttzPXn0bhXyGjM0Hdxcsrc5s=

vendor/github.com/lib/pq/.travis.sh

@@ -70,17 +70,4 @@ postgresql_uninstall() {
 	sudo rm -rf /var/lib/postgresql
 }
 
-megacheck_install() {
-	# Lock megacheck version at $MEGACHECK_VERSION to prevent spontaneous
-	# new error messages in old code.
-	go get -d honnef.co/go/tools/...
-	git -C $GOPATH/src/honnef.co/go/tools/ checkout $MEGACHECK_VERSION
-	go install honnef.co/go/tools/cmd/megacheck
-	megacheck --version
-}
-
-golint_install() {
-	go get github.com/golang/lint/golint
-}
-
 $1

vendor/github.com/lib/pq/README.md

@@ -10,7 +10,7 @@
 ## Docs
 
 For detailed documentation and basic usage examples, please see the package
-documentation at <http://godoc.org/github.com/lib/pq>.
+documentation at <https://godoc.org/github.com/lib/pq>.
 
 ## Tests
 

vendor/github.com/lib/pq/buf.go

@@ -66,7 +66,7 @@ func (b *writeBuf) int16(n int) {
 }
 
 func (b *writeBuf) string(s string) {
-	b.buf = append(b.buf, (s + "\000")...)
+	b.buf = append(append(b.buf, s...), '\000')
 }
 
 func (b *writeBuf) byte(c byte) {

vendor/github.com/lib/pq/conn.go

@@ -2,7 +2,9 @@ package pq
 
 import (
 	"bufio"
+	"context"
 	"crypto/md5"
+	"crypto/sha256"
 	"database/sql"
 	"database/sql/driver"
 	"encoding/binary"
@@ -20,6 +22,7 @@ import (
 	"unicode"
 
 	"github.com/lib/pq/oid"
+	"github.com/lib/pq/scram"
 )
 
 // Common error types
@@ -89,13 +92,25 @@ type Dialer interface {
 	DialTimeout(network, address string, timeout time.Duration) (net.Conn, error)
 }
 
-type defaultDialer struct{}
+// DialerContext is the context-aware dialer interface.
+type DialerContext interface {
+	DialContext(ctx context.Context, network, address string) (net.Conn, error)
+}
+
+type defaultDialer struct {
+	d net.Dialer
+}
 
-func (d defaultDialer) Dial(ntw, addr string) (net.Conn, error) {
-	return net.Dial(ntw, addr)
+func (d defaultDialer) Dial(network, address string) (net.Conn, error) {
+	return d.d.Dial(network, address)
 }
-func (d defaultDialer) DialTimeout(ntw, addr string, timeout time.Duration) (net.Conn, error) {
-	return net.DialTimeout(ntw, addr, timeout)
+func (d defaultDialer) DialTimeout(network, address string, timeout time.Duration) (net.Conn, error) {
+	ctx, cancel := context.WithTimeout(context.Background(), timeout)
+	defer cancel()
+	return d.DialContext(ctx, network, address)
+}
+func (d defaultDialer) DialContext(ctx context.Context, network, address string) (net.Conn, error) {
+	return d.d.DialContext(ctx, network, address)
 }
 
 type conn struct {
@@ -244,90 +259,35 @@ func (cn *conn) writeBuf(b byte) *writeBuf {
 	}
 }
 
-// Open opens a new connection to the database. name is a connection string.
+// Open opens a new connection to the database. dsn is a connection string.
 // Most users should only use it through database/sql package from the standard
 // library.
-func Open(name string) (_ driver.Conn, err error) {
-	return DialOpen(defaultDialer{}, name)
+func Open(dsn string) (_ driver.Conn, err error) {
+	return DialOpen(defaultDialer{}, dsn)
 }
 
 // DialOpen opens a new connection to the database using a dialer.
-func DialOpen(d Dialer, name string) (_ driver.Conn, err error) {
+func DialOpen(d Dialer, dsn string) (_ driver.Conn, err error) {
+	c, err := NewConnector(dsn)
+	if err != nil {
+		return nil, err
+	}
+	c.dialer = d
+	return c.open(context.Background())
+}
+
+func (c *Connector) open(ctx context.Context) (cn *conn, err error) {
 	// Handle any panics during connection initialization.  Note that we
 	// specifically do *not* want to use errRecover(), as that would turn any
 	// connection errors into ErrBadConns, hiding the real error message from
 	// the user.
 	defer errRecoverNoErrBadConn(&err)
 
-	o := make(values)
-
-	// A number of defaults are applied here, in this order:
-	//
-	// * Very low precedence defaults applied in every situation
-	// * Environment variables
-	// * Explicitly passed connection information
-	o["host"] = "localhost"
-	o["port"] = "5432"
-	// N.B.: Extra float digits should be set to 3, but that breaks
-	// Postgres 8.4 and older, where the max is 2.
-	o["extra_float_digits"] = "2"
-	for k, v := range parseEnviron(os.Environ()) {
-		o[k] = v
-	}
-
-	if strings.HasPrefix(name, "postgres://") || strings.HasPrefix(name, "postgresql://") {
-		name, err = ParseURL(name)
-		if err != nil {
-			return nil, err
-		}
-	}
-
-	if err := parseOpts(name, o); err != nil {
-		return nil, err
-	}
-
-	// Use the "fallback" application name if necessary
-	if fallback, ok := o["fallback_application_name"]; ok {
-		if _, ok := o["application_name"]; !ok {
-			o["application_name"] = fallback
-		}
-	}
-
-	// We can't work with any client_encoding other than UTF-8 currently.
-	// However, we have historically allowed the user to set it to UTF-8
-	// explicitly, and there's no reason to break such programs, so allow that.
-	// Note that the "options" setting could also set client_encoding, but
-	// parsing its value is not worth it.  Instead, we always explicitly send
-	// client_encoding as a separate run-time parameter, which should override
-	// anything set in options.
-	if enc, ok := o["client_encoding"]; ok && !isUTF8(enc) {
-		return nil, errors.New("client_encoding must be absent or 'UTF8'")
-	}
-	o["client_encoding"] = "UTF8"
-	// DateStyle needs a similar treatment.
-	if datestyle, ok := o["datestyle"]; ok {
-		if datestyle != "ISO, MDY" {
-			panic(fmt.Sprintf("setting datestyle must be absent or %v; got %v",
-				"ISO, MDY", datestyle))
-		}
-	} else {
-		o["datestyle"] = "ISO, MDY"
-	}
-
-	// If a user is not provided by any other means, the last
-	// resort is to use the current operating system provided user
-	// name.
-	if _, ok := o["user"]; !ok {
-		u, err := userCurrent()
-		if err != nil {
-			return nil, err
-		}
-		o["user"] = u
-	}
+	o := c.opts
 
-	cn := &conn{
+	cn = &conn{
 		opts:   o,
-		dialer: d,
+		dialer: c.dialer,
 	}
 	err = cn.handleDriverSettings(o)
 	if err != nil {
@@ -335,13 +295,16 @@ func DialOpen(d Dialer, name string) (_ driver.Conn, err error) {
 	}
 	cn.handlePgpass(o)
 
-	cn.c, err = dial(d, o)
+	cn.c, err = dial(ctx, c.dialer, o)
 	if err != nil {
 		return nil, err
 	}
 
 	err = cn.ssl(o)
 	if err != nil {
+		if cn.c != nil {
+			cn.c.Close()
+		}
 		return nil, err
 	}
 
@@ -364,10 +327,10 @@ func DialOpen(d Dialer, name string) (_ driver.Conn, err error) {
 	return cn, err
 }
 
-func dial(d Dialer, o values) (net.Conn, error) {
-	ntw, addr := network(o)
+func dial(ctx context.Context, d Dialer, o values) (net.Conn, error) {
+	network, address := network(o)
 	// SSL is not necessary or supported over UNIX domain sockets
-	if ntw == "unix" {
+	if network == "unix" {
 		o["sslmode"] = "disable"
 	}
 
@@ -378,19 +341,30 @@ func dial(d Dialer, o values) (net.Conn, error) {
 			return nil, fmt.Errorf("invalid value for parameter connect_timeout: %s", err)
 		}
 		duration := time.Duration(seconds) * time.Second
+
 		// connect_timeout should apply to the entire connection establishment
 		// procedure, so we both use a timeout for the TCP connection
 		// establishment and set a deadline for doing the initial handshake.
 		// The deadline is then reset after startup() is done.
 		deadline := time.Now().Add(duration)
-		conn, err := d.DialTimeout(ntw, addr, duration)
+		var conn net.Conn
+		if dctx, ok := d.(DialerContext); ok {
+			ctx, cancel := context.WithTimeout(ctx, duration)
+			defer cancel()
+			conn, err = dctx.DialContext(ctx, network, address)
+		} else {
+			conn, err = d.DialTimeout(network, address, duration)
+		}
 		if err != nil {
 			return nil, err
 		}
 		err = conn.SetDeadline(deadline)
 		return conn, err
 	}
-	return d.Dial(ntw, addr)
+	if dctx, ok := d.(DialerContext); ok {
+		return dctx.DialContext(ctx, network, address)
+	}
+	return d.Dial(network, address)
 }
 
 func network(o values) (string, string) {
@@ -576,7 +550,7 @@ func (cn *conn) Commit() (err error) {
 	// would get the same behaviour if you issued a COMMIT in a failed
 	// transaction, so it's also the least surprising thing to do here.
 	if cn.txnStatus == txnStatusInFailedTransaction {
-		if err := cn.Rollback(); err != nil {
+		if err := cn.rollback(); err != nil {
 			return err
 		}
 		return ErrInFailedTransaction
@@ -603,7 +577,10 @@ func (cn *conn) Rollback() (err error) {
 		return driver.ErrBadConn
 	}
 	defer cn.errRecover(&err)
+	return cn.rollback()
+}
 
+func (cn *conn) rollback() (err error) {
 	cn.checkIsInTransaction(true)
 	_, commandTag, err := cn.simpleExec("ROLLBACK")
 	if err != nil {
@@ -704,7 +681,7 @@ func (cn *conn) simpleQuery(q string) (res *rows, err error) {
 			// res might be non-nil here if we received a previous
 			// CommandComplete, but that's fine; just overwrite it
 			res = &rows{cn: cn}
-			res.colNames, res.colFmts, res.colTyps = parsePortalRowDescribe(r)
+			res.rowsHeader = parsePortalRowDescribe(r)
 
 			// To work around a bug in QueryRow in Go 1.2 and earlier, wait
 			// until the first DataRow has been received.
@@ -861,7 +838,7 @@ func (cn *conn) query(query string, args []driver.Value) (_ *rows, err error) {
 		cn.readParseResponse()
 		cn.readBindResponse()
 		rows := &rows{cn: cn}
-		rows.colNames, rows.colFmts, rows.colTyps = cn.readPortalDescribeResponse()
+		rows.rowsHeader = cn.readPortalDescribeResponse()
 		cn.postExecuteWorkaround()
 		return rows, nil
 	}
@@ -869,9 +846,7 @@ func (cn *conn) query(query string, args []driver.Value) (_ *rows, err error) {
 	st.exec(args)
 	return &rows{
 		cn:         cn,
-		colNames: st.colNames,
-		colTyps:  st.colTyps,
-		colFmts:  st.colFmts,
+		rowsHeader: st.rowsHeader,
 	}, nil
 }
 
@@ -992,7 +967,6 @@ func (cn *conn) recv() (t byte, r *readBuf) {
 		if err != nil {
 			panic(err)
 		}
-
 		switch t {
 		case 'E':
 			panic(parseError(r))
@@ -1163,6 +1137,55 @@ func (cn *conn) auth(r *readBuf, o values) {
 		if r.int32() != 0 {
 			errorf("unexpected authentication response: %q", t)
 		}
+	case 10:
+		sc := scram.NewClient(sha256.New, o["user"], o["password"])
+		sc.Step(nil)
+		if sc.Err() != nil {
+			errorf("SCRAM-SHA-256 error: %s", sc.Err().Error())
+		}
+		scOut := sc.Out()
+
+		w := cn.writeBuf('p')
+		w.string("SCRAM-SHA-256")
+		w.int32(len(scOut))
+		w.bytes(scOut)
+		cn.send(w)
+
+		t, r := cn.recv()
+		if t != 'R' {
+			errorf("unexpected password response: %q", t)
+		}
+
+		if r.int32() != 11 {
+			errorf("unexpected authentication response: %q", t)
+		}
+
+		nextStep := r.next(len(*r))
+		sc.Step(nextStep)
+		if sc.Err() != nil {
+			errorf("SCRAM-SHA-256 error: %s", sc.Err().Error())
+		}
+
+		scOut = sc.Out()
+		w = cn.writeBuf('p')
+		w.bytes(scOut)
+		cn.send(w)
+
+		t, r = cn.recv()
+		if t != 'R' {
+			errorf("unexpected password response: %q", t)
+		}
+
+		if r.int32() != 12 {
+			errorf("unexpected authentication response: %q", t)
+		}
+
+		nextStep = r.next(len(*r))
+		sc.Step(nextStep)
+		if sc.Err() != nil {
+			errorf("SCRAM-SHA-256 error: %s", sc.Err().Error())
+		}
+
 	default:
 		errorf("unknown authentication response: %d", code)
 	}
@@ -1182,10 +1205,8 @@ var colFmtDataAllText = []byte{0, 0}
 type stmt struct {
 	cn   *conn
 	name string
-	colNames   []string
-	colFmts    []format
+	rowsHeader
 	colFmtData []byte
-	colTyps    []fieldDesc
 	paramTyps  []oid.Oid
 	closed     bool
 }
@@ -1232,9 +1253,7 @@ func (st *stmt) Query(v []driver.Value) (r driver.Rows, err error) {
 	st.exec(v)
 	return &rows{
 		cn:         st.cn,
-		colNames: st.colNames,
-		colTyps:  st.colTyps,
-		colFmts:  st.colFmts,
+		rowsHeader: st.rowsHeader,
 	}, nil
 }
 
@@ -1344,16 +1363,22 @@ func (cn *conn) parseComplete(commandTag string) (driver.Result, string) {
 	return driver.RowsAffected(n), commandTag
 }
 
-type rows struct {
-	cn       *conn
-	finish   func()
+type rowsHeader struct {
 	colNames []string
 	colTyps  []fieldDesc
 	colFmts  []format
+}
+
+type rows struct {
+	cn     *conn
+	finish func()
+	rowsHeader
 	done   bool
 	rb     readBuf
 	result driver.Result
 	tag    string
+
+	next *rowsHeader
 }
 
 func (rs *rows) Close() error {
@@ -1440,7 +1465,8 @@ func (rs *rows) Next(dest []driver.Value) (err error) {
 			}
 			return
 		case 'T':
-			rs.colNames, rs.colFmts, rs.colTyps = parsePortalRowDescribe(&rs.rb)
+			next := parsePortalRowDescribe(&rs.rb)
+			rs.next = &next
 			return io.EOF
 		default:
 			errorf("unexpected message after execute: %q", t)
@@ -1449,10 +1475,16 @@ func (rs *rows) Next(dest []driver.Value) (err error) {
 }
 
 func (rs *rows) HasNextResultSet() bool {
-	return !rs.done
+	hasNext := rs.next != nil && !rs.done
+	return hasNext
 }
 
 func (rs *rows) NextResultSet() error {
+	if rs.next == nil {
+		return io.EOF
+	}
+	rs.rowsHeader = *rs.next
+	rs.next = nil
 	return nil
 }
 
@@ -1475,6 +1507,39 @@ func QuoteIdentifier(name string) string {
 	return `"` + strings.Replace(name, `"`, `""`, -1) + `"`
 }
 
+// QuoteLiteral quotes a 'literal' (e.g. a parameter, often used to pass literal
+// to DDL and other statements that do not accept parameters) to be used as part
+// of an SQL statement.  For example:
+//
+//    exp_date := pq.QuoteLiteral("2023-01-05 15:00:00Z")
+//    err := db.Exec(fmt.Sprintf("CREATE ROLE my_user VALID UNTIL %s", exp_date))
+//
+// Any single quotes in name will be escaped. Any backslashes (i.e. "\") will be
+// replaced by two backslashes (i.e. "\\") and the C-style escape identifier
+// that PostgreSQL provides ('E') will be prepended to the string.
+func QuoteLiteral(literal string) string {
+	// This follows the PostgreSQL internal algorithm for handling quoted literals
+	// from libpq, which can be found in the "PQEscapeStringInternal" function,
+	// which is found in the libpq/fe-exec.c source file:
+	// https://git.postgresql.org/gitweb/?p=postgresql.git;a=blob;f=src/interfaces/libpq/fe-exec.c
+	//
+	// substitute any single-quotes (') with two single-quotes ('')
+	literal = strings.Replace(literal, `'`, `''`, -1)
+	// determine if the string has any backslashes (\) in it.
+	// if it does, replace any backslashes (\) with two backslashes (\\)
+	// then, we need to wrap the entire string with a PostgreSQL
+	// C-style escape. Per how "PQEscapeStringInternal" handles this case, we
+	// also add a space before the "E"
+	if strings.Contains(literal, `\`) {
+		literal = strings.Replace(literal, `\`, `\\`, -1)
+		literal = ` E'` + literal + `'`
+	} else {
+		// otherwise, we can just wrap the literal with a pair of single quotes
+		literal = `'` + literal + `'`
+	}
+	return literal
+}
+
 func md5s(s string) string {
 	h := md5.New()
 	h.Write([]byte(s))
@@ -1630,13 +1695,13 @@ func (cn *conn) readStatementDescribeResponse() (paramTyps []oid.Oid, colNames [
 	}
 }
 
-func (cn *conn) readPortalDescribeResponse() (colNames []string, colFmts []format, colTyps []fieldDesc) {
+func (cn *conn) readPortalDescribeResponse() rowsHeader {
 	t, r := cn.recv1()
 	switch t {
 	case 'T':
 		return parsePortalRowDescribe(r)
 	case 'n':
-		return nil, nil, nil
+		return rowsHeader{}
 	case 'E':
 		err := parseError(r)
 		cn.readReadyForQuery()
@@ -1742,11 +1807,11 @@ func parseStatementRowDescribe(r *readBuf) (colNames []string, colTyps []fieldDe
 	return
 }
 
-func parsePortalRowDescribe(r *readBuf) (colNames []string, colFmts []format, colTyps []fieldDesc) {
+func parsePortalRowDescribe(r *readBuf) rowsHeader {
 	n := r.int16()
-	colNames = make([]string, n)
-	colFmts = make([]format, n)
-	colTyps = make([]fieldDesc, n)
+	colNames := make([]string, n)
+	colFmts := make([]format, n)
+	colTyps := make([]fieldDesc, n)
 	for i := range colNames {
 		colNames[i] = r.string()
 		r.next(6)
@@ -1755,7 +1820,11 @@ func parsePortalRowDescribe(r *readBuf) (colNames []string, colFmts []format, co
 		colTyps[i].Mod = r.int32()
 		colFmts[i] = format(r.int16())
 	}
-	return
+	return rowsHeader{
+		colNames: colNames,
+		colFmts:  colFmts,
+		colTyps:  colTyps,
+	}
 }
 
 // parseEnviron tries to mimic some of libpq's environment handling

vendor/github.com/lib/pq/conn_go18.go

-// +build go1.8
-
 package pq
 
 import (
@@ -9,6 +7,7 @@ import (
 	"fmt"
 	"io"
 	"io/ioutil"
+	"time"
 )
 
 // Implement the "QueryerContext" interface
@@ -76,13 +75,32 @@ func (cn *conn) BeginTx(ctx context.Context, opts driver.TxOptions) (driver.Tx,
 	return tx, nil
 }
 
+func (cn *conn) Ping(ctx context.Context) error {
+	if finish := cn.watchCancel(ctx); finish != nil {
+		defer finish()
+	}
+	rows, err := cn.simpleQuery("SELECT 'lib/pq ping test';")
+	if err != nil {
+		return driver.ErrBadConn // https://golang.org/pkg/database/sql/driver/#Pinger
+	}
+	rows.Close()
+	return nil
+}
+
 func (cn *conn) watchCancel(ctx context.Context) func() {
 	if done := ctx.Done(); done != nil {
 		finished := make(chan struct{})
 		go func() {
 			select {
 			case <-done:
-				_ = cn.cancel()
+				// At this point the function level context is canceled,
+				// so it must not be used for the additional network
+				// request to cancel the query.
+				// Create a new context to pass into the dial.
+				ctxCancel, cancel := context.WithTimeout(context.Background(), time.Second*10)
+				defer cancel()
+
+				_ = cn.cancel(ctxCancel)
 				finished <- struct{}{}
 			case <-finished:
 			}
@@ -97,8 +115,8 @@ func (cn *conn) watchCancel(ctx context.Context) func() {
 	return nil
 }
 
-func (cn *conn) cancel() error {
-	c, err := dial(cn.dialer, cn.opts)
+func (cn *conn) cancel(ctx context.Context) error {
+	c, err := dial(ctx, cn.dialer, cn.opts)
 	if err != nil {
 		return err
 	}

vendor/github.com/lib/pq/connector.go

-// +build go1.10
-
 package pq
 
 import (
 	"context"
 	"database/sql/driver"
+	"errors"
+	"fmt"
+	"os"
+	"strings"
 )
 
 // Connector represents a fixed configuration for the pq driver with a given
@@ -14,30 +16,95 @@ import (
 //
 // See https://golang.org/pkg/database/sql/driver/#Connector.
 // See https://golang.org/pkg/database/sql/#OpenDB.
-type connector struct {
-	name string
+type Connector struct {
+	opts   values
+	dialer Dialer
 }
 
 // Connect returns a connection to the database using the fixed configuration
 // of this Connector. Context is not used.
-func (c *connector) Connect(_ context.Context) (driver.Conn, error) {
-	return (&Driver{}).Open(c.name)
+func (c *Connector) Connect(ctx context.Context) (driver.Conn, error) {
+	return c.open(ctx)
 }
 
 // Driver returnst the underlying driver of this Connector.
-func (c *connector) Driver() driver.Driver {
+func (c *Connector) Driver() driver.Driver {
 	return &Driver{}
 }
 
-var _ driver.Connector = &connector{}
-
 // NewConnector returns a connector for the pq driver in a fixed configuration
-// with the given name. The returned connector can be used to create any number
+// with the given dsn. The returned connector can be used to create any number
 // of equivalent Conn's. The returned connector is intended to be used with
 // database/sql.OpenDB.
 //
 // See https://golang.org/pkg/database/sql/driver/#Connector.
 // See https://golang.org/pkg/database/sql/#OpenDB.
-func NewConnector(name string) (driver.Connector, error) {
-	return &connector{name: name}, nil
+func NewConnector(dsn string) (*Connector, error) {
+	var err error
+	o := make(values)
+
+	// A number of defaults are applied here, in this order:
+	//
+	// * Very low precedence defaults applied in every situation
+	// * Environment variables
+	// * Explicitly passed connection information
+	o["host"] = "localhost"
+	o["port"] = "5432"
+	// N.B.: Extra float digits should be set to 3, but that breaks
+	// Postgres 8.4 and older, where the max is 2.
+	o["extra_float_digits"] = "2"
+	for k, v := range parseEnviron(os.Environ()) {
+		o[k] = v
+	}
+
+	if strings.HasPrefix(dsn, "postgres://") || strings.HasPrefix(dsn, "postgresql://") {
+		dsn, err = ParseURL(dsn)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	if err := parseOpts(dsn, o); err != nil {
+		return nil, err
+	}
+
+	// Use the "fallback" application name if necessary
+	if fallback, ok := o["fallback_application_name"]; ok {
+		if _, ok := o["application_name"]; !ok {
+			o["application_name"] = fallback
+		}
+	}
+
+	// We can't work with any client_encoding other than UTF-8 currently.
+	// However, we have historically allowed the user to set it to UTF-8
+	// explicitly, and there's no reason to break such programs, so allow that.
+	// Note that the "options" setting could also set client_encoding, but
+	// parsing its value is not worth it.  Instead, we always explicitly send
+	// client_encoding as a separate run-time parameter, which should override
+	// anything set in options.
+	if enc, ok := o["client_encoding"]; ok && !isUTF8(enc) {
+		return nil, errors.New("client_encoding must be absent or 'UTF8'")
+	}
+	o["client_encoding"] = "UTF8"
+	// DateStyle needs a similar treatment.
+	if datestyle, ok := o["datestyle"]; ok {
+		if datestyle != "ISO, MDY" {
+			return nil, fmt.Errorf("setting datestyle must be absent or %v; got %v", "ISO, MDY", datestyle)
+		}
+	} else {
+		o["datestyle"] = "ISO, MDY"
+	}
+
+	// If a user is not provided by any other means, the last
+	// resort is to use the current operating system provided user
+	// name.
+	if _, ok := o["user"]; !ok {
+		u, err := userCurrent()
+		if err != nil {
+			return nil, err
+		}
+		o["user"] = u
+	}
+
+	return &Connector{opts: o, dialer: defaultDialer{}}, nil
 }

vendor/github.com/lib/pq/doc.go

@@ -239,7 +239,7 @@ for more information).  Note that the channel name will be truncated to 63
 bytes by the PostgreSQL server.
 
 You can find a complete, working example of Listener usage at
-http://godoc.org/github.com/lib/pq/example/listen.
+https://godoc.org/github.com/lib/pq/example/listen.
 
 */
 package pq

vendor/github.com/lib/pq/encode.go

@@ -117,11 +117,10 @@ func textDecode(parameterStatus *parameterStatus, s []byte, typ oid.Oid) interfa
 		}
 		return i
 	case oid.T_float4, oid.T_float8:
-		bits := 64
-		if typ == oid.T_float4 {
-			bits = 32
-		}
-		f, err := strconv.ParseFloat(string(s), bits)
+		// We always use 64 bit parsing, regardless of whether the input text is for
+		// a float4 or float8, because clients expect float64s for all float datatypes
+		// and returning a 32-bit parsed float64 produces lossy results.
+		f, err := strconv.ParseFloat(string(s), 64)
 		if err != nil {
 			errorf("%s", err)
 		}

vendor/github.com/lib/pq/error.go

@@ -478,13 +478,13 @@ func errRecoverNoErrBadConn(err *error) {
 	}
 }
 
-func (c *conn) errRecover(err *error) {
+func (cn *conn) errRecover(err *error) {
 	e := recover()
 	switch v := e.(type) {
 	case nil:
 		// Do nothing
 	case runtime.Error:
-		c.bad = true
+		cn.bad = true
 		panic(v)
 	case *Error:
 		if v.Fatal() {
@@ -493,7 +493,7 @@ func (c *conn) errRecover(err *error) {
 			*err = v
 		}
 	case *net.OpError:
-		c.bad = true
+		cn.bad = true
 		*err = v
 	case error:
 		if v == io.EOF || v.(error).Error() == "remote error: handshake failure" {
@@ -503,13 +503,13 @@ func (c *conn) errRecover(err *error) {
 		}
 
 	default:
-		c.bad = true
+		cn.bad = true
 		panic(fmt.Sprintf("unknown error: %#v", e))
 	}
 
 	// Any time we return ErrBadConn, we need to remember it since *Tx doesn't
 	// mark the connection bad in database/sql.
 	if *err == driver.ErrBadConn {
-		c.bad = true
+		cn.bad = true
 	}
 }

vendor/github.com/lib/pq/scram/scram.go

+// Copyright (c) 2014 - Gustavo Niemeyer <gustavo@niemeyer.net>
+//
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this
+//    list of conditions and the following disclaimer.
+// 2. Redistributions in binary form must reproduce the above copyright notice,
+//    this list of conditions and the following disclaimer in the documentation
+//    and/or other materials provided with the distribution.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+// ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Package scram implements a SCRAM-{SHA-1,etc} client per RFC5802.
+//
+// http://tools.ietf.org/html/rfc5802
+//
+package scram
+
+import (
+	"bytes"
+	"crypto/hmac"
+	"crypto/rand"
+	"encoding/base64"
+	"fmt"
+	"hash"
+	"strconv"
+	"strings"
+)
+
+// Client implements a SCRAM-* client (SCRAM-SHA-1, SCRAM-SHA-256, etc).
+//
+// A Client may be used within a SASL conversation with logic resembling:
+//
+//    var in []byte
+//    var client = scram.NewClient(sha1.New, user, pass)
+//    for client.Step(in) {
+//            out := client.Out()
+//            // send out to server
+//            in := serverOut
+//    }
+//    if client.Err() != nil {
+//            // auth failed
+//    }
+//
+type Client struct {
+	newHash func() hash.Hash
+
+	user string
+	pass string
+	step int
+	out  bytes.Buffer
+	err  error
+
+	clientNonce []byte
+	serverNonce []byte
+	saltedPass  []byte
+	authMsg     bytes.Buffer
+}
+
+// NewClient returns a new SCRAM-* client with the provided hash algorithm.
+//
+// For SCRAM-SHA-256, for example, use:
+//
+//    client := scram.NewClient(sha256.New, user, pass)
+//
+func NewClient(newHash func() hash.Hash, user, pass string) *Client {
+	c := &Client{
+		newHash: newHash,
+		user:    user,
+		pass:    pass,
+	}
+	c.out.Grow(256)
+	c.authMsg.Grow(256)
+	return c
+}
+
+// Out returns the data to be sent to the server in the current step.
+func (c *Client) Out() []byte {
+	if c.out.Len() == 0 {
+		return nil
+	}
+	return c.out.Bytes()
+}
+
+// Err returns the error that ocurred, or nil if there were no errors.
+func (c *Client) Err() error {
+	return c.err
+}
+
+// SetNonce sets the client nonce to the provided value.
+// If not set, the nonce is generated automatically out of crypto/rand on the first step.
+func (c *Client) SetNonce(nonce []byte) {
+	c.clientNonce = nonce
+}
+
+var escaper = strings.NewReplacer("=", "=3D", ",", "=2C")
+
+// Step processes the incoming data from the server and makes the
+// next round of data for the server available via Client.Out.
+// Step returns false if there are no errors and more data is
+// still expected.
+func (c *Client) Step(in []byte) bool {
+	c.out.Reset()
+	if c.step > 2 || c.err != nil {
+		return false
+	}
+	c.step++
+	switch c.step {
+	case 1:
+		c.err = c.step1(in)
+	case 2:
+		c.err = c.step2(in)
+	case 3:
+		c.err = c.step3(in)
+	}
+	return c.step > 2 || c.err != nil
+}
+
+func (c *Client) step1(in []byte) error {
+	if len(c.clientNonce) == 0 {
+		const nonceLen = 16
+		buf := make([]byte, nonceLen+b64.EncodedLen(nonceLen))
+		if _, err := rand.Read(buf[:nonceLen]); err != nil {
+			return fmt.Errorf("cannot read random SCRAM-SHA-256 nonce from operating system: %v", err)
+		}
+		c.clientNonce = buf[nonceLen:]
+		b64.Encode(c.clientNonce, buf[:nonceLen])
+	}
+	c.authMsg.WriteString("n=")
+	escaper.WriteString(&c.authMsg, c.user)
+	c.authMsg.WriteString(",r=")
+	c.authMsg.Write(c.clientNonce)
+
+	c.out.WriteString("n,,")
+	c.out.Write(c.authMsg.Bytes())
+	return nil
+}
+
+var b64 = base64.StdEncoding
+
+func (c *Client) step2(in []byte) error {
+	c.authMsg.WriteByte(',')
+	c.authMsg.Write(in)
+
+	fields := bytes.Split(in, []byte(","))
+	if len(fields) != 3 {
+		return fmt.Errorf("expected 3 fields in first SCRAM-SHA-256 server message, got %d: %q", len(fields), in)
+	}
+	if !bytes.HasPrefix(fields[0], []byte("r=")) || len(fields[0]) < 2 {
+		return fmt.Errorf("server sent an invalid SCRAM-SHA-256 nonce: %q", fields[0])
+	}
+	if !bytes.HasPrefix(fields[1], []byte("s=")) || len(fields[1]) < 6 {
+		return fmt.Errorf("server sent an invalid SCRAM-SHA-256 salt: %q", fields[1])
+	}
+	if !bytes.HasPrefix(fields[2], []byte("i=")) || len(fields[2]) < 6 {
+		return fmt.Errorf("server sent an invalid SCRAM-SHA-256 iteration count: %q", fields[2])
+	}
+
+	c.serverNonce = fields[0][2:]
+	if !bytes.HasPrefix(c.serverNonce, c.clientNonce) {
+		return fmt.Errorf("server SCRAM-SHA-256 nonce is not prefixed by client nonce: got %q, want %q+\"...\"", c.serverNonce, c.clientNonce)
+	}
+
+	salt := make([]byte, b64.DecodedLen(len(fields[1][2:])))
+	n, err := b64.Decode(salt, fields[1][2:])
+	if err != nil {
+		return fmt.Errorf("cannot decode SCRAM-SHA-256 salt sent by server: %q", fields[1])
+	}
+	salt = salt[:n]
+	iterCount, err := strconv.Atoi(string(fields[2][2:]))
+	if err != nil {
+		return fmt.Errorf("server sent an invalid SCRAM-SHA-256 iteration count: %q", fields[2])
+	}
+	c.saltPassword(salt, iterCount)
+
+	c.authMsg.WriteString(",c=biws,r=")
+	c.authMsg.Write(c.serverNonce)
+
+	c.out.WriteString("c=biws,r=")
+	c.out.Write(c.serverNonce)
+	c.out.WriteString(",p=")
+	c.out.Write(c.clientProof())
+	return nil
+}
+
+func (c *Client) step3(in []byte) error {
+	var isv, ise bool
+	var fields = bytes.Split(in, []byte(","))
+	if len(fields) == 1 {
+		isv = bytes.HasPrefix(fields[0], []byte("v="))
+		ise = bytes.HasPrefix(fields[0], []byte("e="))
+	}
+	if ise {
+		return fmt.Errorf("SCRAM-SHA-256 authentication error: %s", fields[0][2:])
+	} else if !isv {
+		return fmt.Errorf("unsupported SCRAM-SHA-256 final message from server: %q", in)
+	}
+	if !bytes.Equal(c.serverSignature(), fields[0][2:]) {
+		return fmt.Errorf("cannot authenticate SCRAM-SHA-256 server signature: %q", fields[0][2:])
+	}
+	return nil
+}
+
+func (c *Client) saltPassword(salt []byte, iterCount int) {
+	mac := hmac.New(c.newHash, []byte(c.pass))
+	mac.Write(salt)
+	mac.Write([]byte{0, 0, 0, 1})
+	ui := mac.Sum(nil)
+	hi := make([]byte, len(ui))
+	copy(hi, ui)
+	for i := 1; i < iterCount; i++ {
+		mac.Reset()
+		mac.Write(ui)
+		mac.Sum(ui[:0])
+		for j, b := range ui {
+			hi[j] ^= b
+		}
+	}
+	c.saltedPass = hi
+}
+
+func (c *Client) clientProof() []byte {
+	mac := hmac.New(c.newHash, c.saltedPass)
+	mac.Write([]byte("Client Key"))
+	clientKey := mac.Sum(nil)
+	hash := c.newHash()
+	hash.Write(clientKey)
+	storedKey := hash.Sum(nil)
+	mac = hmac.New(c.newHash, storedKey)
+	mac.Write(c.authMsg.Bytes())
+	clientProof := mac.Sum(nil)
+	for i, b := range clientKey {
+		clientProof[i] ^= b
+	}
+	clientProof64 := make([]byte, b64.EncodedLen(len(clientProof)))
+	b64.Encode(clientProof64, clientProof)
+	return clientProof64
+}
+
+func (c *Client) serverSignature() []byte {
+	mac := hmac.New(c.newHash, c.saltedPass)
+	mac.Write([]byte("Server Key"))
+	serverKey := mac.Sum(nil)
+
+	mac = hmac.New(c.newHash, serverKey)
+	mac.Write(c.authMsg.Bytes())
+	serverSignature := mac.Sum(nil)
+
+	encoded := make([]byte, b64.EncodedLen(len(serverSignature)))
+	b64.Encode(encoded, serverSignature)
+	return encoded
+}

vendor/github.com/lib/pq/ssl.go

@@ -58,7 +58,13 @@ func ssl(o values) (func(net.Conn) (net.Conn, error), error) {
 	if err != nil {
 		return nil, err
 	}
-	sslRenegotiation(&tlsConf)
+
+	// Accept renegotiation requests initiated by the backend.
+	//
+	// Renegotiation was deprecated then removed from PostgreSQL 9.5, but
+	// the default configuration of older versions has it enabled. Redshift
+	// also initiates renegotiations and cannot be reconfigured.
+	tlsConf.Renegotiation = tls.RenegotiateFreelyAsClient
 
 	return func(conn net.Conn) (net.Conn, error) {
 		client := tls.Client(conn, &tlsConf)

vendor/github.com/lib/pq/ssl_go1.7.go

-// +build go1.7
-
-package pq
-
-import "crypto/tls"
-
-// Accept renegotiation requests initiated by the backend.
-//
-// Renegotiation was deprecated then removed from PostgreSQL 9.5, but
-// the default configuration of older versions has it enabled. Redshift
-// also initiates renegotiations and cannot be reconfigured.
-func sslRenegotiation(conf *tls.Config) {
-	conf.Renegotiation = tls.RenegotiateFreelyAsClient
-}

vendor/github.com/lib/pq/ssl_renegotiation.go

-// +build !go1.7
-
-package pq
-
-import "crypto/tls"
-
-// Renegotiation is not supported by crypto/tls until Go 1.7.
-func sslRenegotiation(*tls.Config) {}

vendor/modules.txt

@@ -139,9 +139,10 @@ github.com/klauspost/compress/gzip
 github.com/klauspost/compress/flate
 # github.com/klauspost/cpuid v1.2.0
 github.com/klauspost/cpuid
-# github.com/lib/pq v1.0.0
+# github.com/lib/pq v1.2.0
 github.com/lib/pq
 github.com/lib/pq/oid
+github.com/lib/pq/scram
 # github.com/mattn/go-colorable v0.1.1
 github.com/mattn/go-colorable
 # github.com/mattn/go-isatty v0.0.7