reference kex and mac algo constants

Depends on gitlab-org/golang-crypto!5

go.mod

@@ -15,7 +15,7 @@ require (
 	github.com/stretchr/testify v1.7.0
 	gitlab.com/gitlab-org/gitaly/v14 v14.9.0-rc5.0.20220329111719-51da8bc17059
 	gitlab.com/gitlab-org/labkit v1.14.0
-	golang.org/x/crypto v0.0.0-20210921155107-089bfa567519
+	golang.org/x/crypto v0.0.0-20220518034528-6f7dac969898
 	golang.org/x/sync v0.0.0-20210220032951-036812b2e83c
 	google.golang.org/grpc v1.40.0
 	gopkg.in/yaml.v2 v2.4.0
@@ -70,6 +70,7 @@ require (
 	golang.org/x/net v0.0.0-20211112202133-69e39bad7dc2 // indirect
 	golang.org/x/oauth2 v0.0.0-20210805134026-6f1e6394065a // indirect
 	golang.org/x/sys v0.0.0-20220114195835-da31bd327af9 // indirect
+	golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1 // indirect
 	golang.org/x/text v0.3.7 // indirect
 	golang.org/x/time v0.0.0-20210220033141-f8bda1e9f3ba // indirect
 	golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 // indirect
@@ -81,4 +82,4 @@ require (
 	gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c // indirect
 )
 
-replace golang.org/x/crypto => gitlab.com/gitlab-org/golang-crypto v0.0.0-20220518204012-9dd4a7273aac
+replace golang.org/x/crypto => gitlab.com/gitlab-org/golang-crypto v0.0.0-20220523184437-e427c5017c17

go.sum

@@ -890,6 +890,8 @@ gitlab.com/gitlab-org/gitlab-shell v1.9.8-0.20201117050822-3f9890ef73dc/go.mod h
 gitlab.com/gitlab-org/gitlab-shell v1.9.8-0.20210720163109-50da611814d2/go.mod h1:QWDYBwuy24qGMandtCngLRPzFgnGPg6LSNoJWPKmJMc=
 gitlab.com/gitlab-org/golang-crypto v0.0.0-20220518204012-9dd4a7273aac h1:qNUzqBTbEGGjF5Fp0NWz3rNmqamwchxM+QKUZYeOS1c=
 gitlab.com/gitlab-org/golang-crypto v0.0.0-20220518204012-9dd4a7273aac/go.mod h1:IxCIyHEi3zRg3s0A5j5BB6A9Jmi73HwBIUl50j+osU4=
+gitlab.com/gitlab-org/golang-crypto v0.0.0-20220523184437-e427c5017c17 h1:zbnh+Y2TX7D+EFNO56GOW3/WXBLly40QdFxkRChXnFQ=
+gitlab.com/gitlab-org/golang-crypto v0.0.0-20220523184437-e427c5017c17/go.mod h1:IxCIyHEi3zRg3s0A5j5BB6A9Jmi73HwBIUl50j+osU4=
 gitlab.com/gitlab-org/labkit v0.0.0-20190221122536-0c3fc7cdd57c/go.mod h1:rYhLgfrbEcyfinG+R3EvKu6bZSsmwQqcXzLfHWSfUKM=
 gitlab.com/gitlab-org/labkit v0.0.0-20200908084045-45895e129029/go.mod h1:SNfxkfUwVNECgtmluVayv0GWFgEjjBs5AzgsowPQuo0=
 gitlab.com/gitlab-org/labkit v1.0.0/go.mod h1:nohrYTSLDnZix0ebXZrbZJjymRar8HeV2roWL5/jw2U=

internal/sshd/server_config.go

@@ -18,21 +18,21 @@ import (
 
 var (
 	supportedMACs = []string{
-		"hmac-sha2-256-etm@openssh.com",
-		"hmac-sha2-512-etm@openssh.com",
-		"hmac-sha2-256",
-		"hmac-sha2-512",
-		"hmac-sha1",
+		ssh.MacAlgoHmacSHA2256ETM,
+		ssh.MacAlgoHmacSHA2512ETM,
+		ssh.MacAlgoHmacSHA2256,
+		ssh.MacAlgoHmacSHA2512,
+		ssh.MacAlgoHmacSHA1,
 	}
 
 	supportedKeyExchanges = []string{
-		"curve25519-sha256",
-		"curve25519-sha256@libssh.org",
-		"ecdh-sha2-nistp256",
-		"ecdh-sha2-nistp384",
-		"ecdh-sha2-nistp521",
-		"diffie-hellman-group14-sha256",
-		"diffie-hellman-group14-sha1",
+		ssh.KexAlgoCurve25519SHA256,
+		ssh.KexAlgoCurve25519SHA256LibSSH,
+		ssh.KexAlgoECDH256,
+		ssh.KexAlgoECDH384,
+		ssh.KexAlgoECDH521,
+		ssh.KexAlgoDH14SHA256,
+		ssh.KexAlgoDH14SHA1,
 	}
 )
 

internal/sshd/server_config_test.go

@@ -105,8 +105,8 @@ func TestDefaultAlgorithms(t *testing.T) {
 }
 
 func TestCustomAlgorithms(t *testing.T) {
-	customMACs := []string{"hmac-sha2-512-etm@openssh.com"}
-	customKexAlgos := []string{"curve25519-sha256"}
+	customMACs := []string{ssh.MacAlgoHmacSHA2512ETM}
+	customKexAlgos := []string{ssh.KexAlgoCurve25519SHA256}
 	customCiphers := []string{"aes256-gcm@openssh.com"}
 
 	srvCfg := &serverConfig{