add Kerberos auth (denisenkom#35)

* add kerberos auth

* added kerberos auth

* Krb auth (denisenkom#1)

* add windows stub for krb

* add import for msdsn

* fix ci lint issue

Co-authored-by: chandan jain <[email protected]>

* build tag for go 1.13

* Remove krb dep (denisenkom#2)

* remove krb dep for windows

* remove krb dep

* unit test coverage

Co-authored-by: chandan jain <[email protected]>

* add Kerberos and KerberosConfig structs

* make krb cache and keyta mutually excusive

* add krb5 provider

* add krb conn str examples

* update krb con str example

* update krb params info

Co-authored-by: chandan jain <[email protected]>
Co-authored-by: shwetamoharil <[email protected]>

Author: 3 people

README.md

@@ -28,6 +28,7 @@ Other supported formats are listed below.
   * `false` - Data sent between client and server is not encrypted beyond the login packet. (Default)
   * `true` - Data sent between client and server is encrypted.
 * `app name` - The application name (default is go-mssqldb)
+* `authenticator` - Can be used to specify use of a registered authentication provider. (e.g. ntlm, winsspi (on windows) or krb5 (on linux))
 
 ### Connection parameters for ODBC and ADO style connection strings
 
@@ -59,6 +60,32 @@ Other supported formats are listed below.
 * `Workstation ID` - The workstation name (default is the host name)
 * `ApplicationIntent` - Can be given the value `ReadOnly` to initiate a read-only connection to an Availability Group listener. The `database` must be specified when connecting with `Application Intent` set to `ReadOnly`.
 
+### Kerberos Active Directory authentication outside Windows
+The package supports authentication via 3 methods.
+
+* Keytabs - Specify the username, keytab file, the krb5.conf file, and realm.
+
+      authenticator=krb5;server=DatabaseServerName;database=DBName;user id=MyUserName;realm=domain.com;krb5conffile=/etc/krb5.conf;keytabfile=~/MyUserName.keytab
+
+* Credential Cache - Specify the krb5.conf file path and credential cache file path.
+
+      authenticator=krb5;server=DatabaseServerName;database=DBName;krb5conffile=/etc/krb5.conf;krbcache=~/MyUserNameCachedCreds
+
+* Raw credentials - Specity krb5.confg, Username, Password and Realm.
+
+      authenticator=krb5;server=DatabaseServerName;database=DBName;user id=MyUserName;password=foo;realm=comani.com;krb5conffile=/etc/krb5.conf;
+
+### Kerberos Parameters
+
+* `authenticator` - set this to `krb5` to enable kerberos authentication. If this is not present, the default provider would be `ntlm` for unix and `winsspi` for windows.
+* `krb5conffile` (mandatory) - path to kerberos configuration file. 
+* `realm` (required with keytab and raw credentials) - Domain name for kerberos authentication. 
+* `keytabfile` - path to Keytab file.
+* `krbcache` - path to Credential cache.
+* For further information on usage: 
+  * <https://web.mit.edu/kerberos/krb5-1.12/doc/admin/conf_files/krb5_conf.html>
+  * <https://web.mit.edu/kerberos/krb5-1.12/doc/basic/index.html>
+
 ### The connection string can be specified in one of three formats
 
 1. URL: with `sqlserver` scheme. username and password appears before the host. Any instance appears as
@@ -88,11 +115,17 @@ Other supported formats are listed below.
 
     ```
 
+* `sqlserver://username@host/instance?krb5conffile=path/to/file&krbcache=/path/to/cache`
+    * `sqlserver://username@host/instance?krb5conffile=path/to/file&realm=domain.com&keytabfile=/path/to/keytabfile`
+
 2. ADO: `key=value` pairs separated by `;`. Values may not contain `;`, leading and trailing whitespace is ignored.
      Examples:
 
     * `server=localhost\\SQLExpress;user id=sa;database=master;app name=MyAppName`
     * `server=localhost;user id=sa;database=master;app name=MyAppName`
+    * `server=localhost;user id=sa;database=master;app name=MyAppName;krb5conffile=path/to/file;krbcache=path/to/cache;authenticator=krb5`
+    * `server=localhost;user id=sa;database=master;app name=MyAppName;krb5conffile=path/to/file;realm=domain.com;keytabfile=path/to/keytabfile;authenticator=krb5`
+
 
     ADO strings support synonyms for database, app name, user id, and server
     * server <= addr, address, network address, data source
@@ -112,6 +145,8 @@ Other supported formats are listed below.
     * `odbc:server=localhost;user id=sa;password=foo}bar`   // Literal `}`, password is "foo}bar"
     * `odbc:server=localhost;user id=sa;password={foo{bar}` // Literal `{`, password is "foo{bar"
     * `odbc:server=localhost;user id=sa;password={foo}}bar}` // Escaped `} with`}}`, password is "foo}bar"
+    * `odbc:server=localhost;user id=sa;database=master;app name=MyAppName;krb5conffile=path/to/file;krbcache=path/to/cache;authenticator=krb5`
+    * `odbc:server=localhost;user id=sa;database=master;app name=MyAppName;krb5conffile=path/to/file;realm=domain.com;keytabfile=path/to/keytabfile;authenticator=krb5`
 
 ### Azure Active Directory authentication
 
@@ -322,6 +357,7 @@ db.QueryContext(ctx, `select * from t2 where user_name = @p1;`, mssql.VarChar(na
 * Supports Single-Sign-On on Windows
 * Supports connections to AlwaysOn Availability Group listeners, including re-direction to read-only replicas.
 * Supports query notifications
+* Supports Kerberos Authentication
 
 ## Tests
 

go.mod

@@ -10,6 +10,7 @@ require (
 	github.com/golang-sql/civil v0.0.0-20190719163853-cb61b32ac6fe
 	github.com/golang-sql/sqlexp v0.1.0
 	github.com/google/uuid v1.3.0 // indirect
+	github.com/jcmturner/gokrb5/v8 v8.4.2
 	github.com/pkg/browser v0.0.0-20210911075715-681adbf594b8 // indirect
 	golang.org/x/crypto v0.0.0-20220511200225-c6db032c6c88
 	golang.org/x/sys v0.0.0-20220224120231-95c6836cb0e7 // indirect

go.sum

@@ -25,6 +25,24 @@ github.com/golang-sql/sqlexp v0.1.0/go.mod h1:J4ad9Vo8ZCWQ2GMrC4UCQy1JpCbwU9m3EO
 github.com/google/uuid v1.1.1/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/google/uuid v1.3.0 h1:t6JiXgmwXMjEs8VusXIJk2BXHsn+wx8BZdTaoZ5fu7I=
 github.com/google/uuid v1.3.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/gorilla/securecookie v1.1.1 h1:miw7JPhV+b/lAHSXz4qd/nN9jRiAFV5FwjeKyCS8BvQ=
+github.com/gorilla/securecookie v1.1.1/go.mod h1:ra0sb63/xPlUeL+yeDciTfxMRAA+MP+HVt/4epWDjd4=
+github.com/gorilla/sessions v1.2.1 h1:DHd3rPN5lE3Ts3D8rKkQ8x/0kqfeNmBAaiSi+o7FsgI=
+github.com/gorilla/sessions v1.2.1/go.mod h1:dk2InVEVJ0sfLlnXv9EAgkf6ecYs/i80K/zI+bUmuGM=
+github.com/hashicorp/go-uuid v1.0.2 h1:cfejS+Tpcp13yd5nYHWDI6qVCny6wyX2Mt5SGur2IGE=
+github.com/hashicorp/go-uuid v1.0.2/go.mod h1:6SBZvOh/SIDV7/2o3Jml5SYk/TvGqwFJ/bN7x4byOro=
+github.com/jcmturner/aescts/v2 v2.0.0 h1:9YKLH6ey7H4eDBXW8khjYslgyqG2xZikXP0EQFKrle8=
+github.com/jcmturner/aescts/v2 v2.0.0/go.mod h1:AiaICIRyfYg35RUkr8yESTqvSy7csK90qZ5xfvvsoNs=
+github.com/jcmturner/dnsutils/v2 v2.0.0 h1:lltnkeZGL0wILNvrNiVCR6Ro5PGU/SeBvVO/8c/iPbo=
+github.com/jcmturner/dnsutils/v2 v2.0.0/go.mod h1:b0TnjGOvI/n42bZa+hmXL+kFJZsFT7G4t3HTlQ184QM=
+github.com/jcmturner/gofork v1.0.0 h1:J7uCkflzTEhUZ64xqKnkDxq3kzc96ajM1Gli5ktUem8=
+github.com/jcmturner/gofork v1.0.0/go.mod h1:MK8+TM0La+2rjBD4jE12Kj1pCCxK7d2LK/UM3ncEo0o=
+github.com/jcmturner/goidentity/v6 v6.0.1 h1:VKnZd2oEIMorCTsFBnJWbExfNN7yZr3EhJAxwOkZg6o=
+github.com/jcmturner/goidentity/v6 v6.0.1/go.mod h1:X1YW3bgtvwAXju7V3LCIMpY0Gbxyjn/mY9zx4tFonSg=
+github.com/jcmturner/gokrb5/v8 v8.4.2 h1:6ZIM6b/JJN0X8UM43ZOM6Z4SJzla+a/u7scXFJzodkA=
+github.com/jcmturner/gokrb5/v8 v8.4.2/go.mod h1:sb+Xq/fTY5yktf/VxLsE3wlfPqQjp0aWNYyvBVK62bc=
+github.com/jcmturner/rpc/v2 v2.0.3 h1:7FXXj8Ti1IaVFpSAziCZWNzbNuZmnvw/i6CqLNdWfZY=
+github.com/jcmturner/rpc/v2 v2.0.3/go.mod h1:VUJYCIDm3PVOEHw8sgt091/20OJjskO/YJki3ELg/Hc=
 github.com/kylelemons/godebug v1.1.0 h1:RPNrshWIDI6G2gRW9EHilWtl7Z6Sb1BR0xunSBf0SNc=
 github.com/kylelemons/godebug v1.1.0/go.mod h1:9/0rRGxNHcop5bhtWyNeEfOS8JIWk580+fNqagV/RAw=
 github.com/modocache/gover v0.0.0-20171022184752-b58185e213c5/go.mod h1:caMODM3PzxT8aQXRPkAt8xlV/e7d7w8GM5g0fa5F0D8=
@@ -35,13 +53,17 @@ github.com/pkg/browser v0.0.0-20210911075715-681adbf594b8/go.mod h1:HKlIX3XHQyzL
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+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=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
+golang.org/x/crypto v0.0.0-20201112155050-0c6587e931a9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/crypto v0.0.0-20220511200225-c6db032c6c88 h1:Tgea0cVUD0ivh5ADBX4WwuI12DUd2to3nCYe2eayMIw=
 golang.org/x/crypto v0.0.0-20220511200225-c6db032c6c88/go.mod h1:IxCIyHEi3zRg3s0A5j5BB6A9Jmi73HwBIUl50j+osU4=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/net v0.0.0-20200114155413-6afb5195e5aa/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20201010224723-4f7140c49acb/go.mod h1:sp8m0HH+o8qH0wwXwYZr8TS3Oi6o0r6Gce1SSxlDquU=
 golang.org/x/net v0.0.0-20211112202133-69e39bad7dc2/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
 golang.org/x/net v0.0.0-20220425223048-2871e0cb64e4 h1:HVyaeDAYux4pnY+D/SiwmLOR36ewZ4iGQIIrtnuCjFA=
@@ -68,6 +90,7 @@ golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGm
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v2 v2.2.1/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
+gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.2.8/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.4.0 h1:D8xgwECY7CYvx+Y2n4sBz93Jn9JRvxdiyyo8CTfuKaY=
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