libpq-remove-scm-auth.patch

diff --git a/src/include/libpq/pqcomm.h b/src/include/libpq/pqcomm.h
index 5268d442ab..84388b8025 100644
--- a/src/include/libpq/pqcomm.h
+++ b/src/include/libpq/pqcomm.h
@@ -116,7 +116,8 @@ extern PGDLLIMPORT bool Db_user_namespace;
 #define AUTH_REQ_PASSWORD	3	/* Password */
 #define AUTH_REQ_CRYPT		4	/* crypt password. Not supported any more. */
 #define AUTH_REQ_MD5		5	/* md5 password */
-#define AUTH_REQ_SCM_CREDS	6	/* transfer SCM credentials */
+#define AUTH_REQ_SCM_CREDS	6	/* transfer SCM credentials.  Not supported
+								 * any more */
 #define AUTH_REQ_GSS		7	/* GSSAPI without wrap() */
 #define AUTH_REQ_GSS_CONT	8	/* Continue GSS exchanges */
 #define AUTH_REQ_SSPI		9	/* SSPI negotiate without wrap() */
diff --git a/src/interfaces/libpq/fe-auth.c b/src/interfaces/libpq/fe-auth.c
index a3b80dc550..f6c2a5f94b 100644
--- a/src/interfaces/libpq/fe-auth.c
+++ b/src/interfaces/libpq/fe-auth.c
@@ -688,68 +688,6 @@ pg_SASL_continue(PGconn *conn, int payloadlen, bool final)
 	return STATUS_OK;
 }
 
-/*
- * Respond to AUTH_REQ_SCM_CREDS challenge.
- *
- * Note: this is dead code as of Postgres 9.1, because current backends will
- * never send this challenge.  But we must keep it as long as libpq needs to
- * interoperate with pre-9.1 servers.  It is believed to be needed only on
- * Debian/kFreeBSD (ie, FreeBSD kernel with Linux userland, so that the
- * getpeereid() function isn't provided by libc).
- */
-static int
-pg_local_sendauth(PGconn *conn)
-{
-#ifdef HAVE_STRUCT_CMSGCRED
-	char		buf;
-	struct iovec iov;
-	struct msghdr msg;
-	struct cmsghdr *cmsg;
-	union
-	{
-		struct cmsghdr hdr;
-		unsigned char buf[CMSG_SPACE(sizeof(struct cmsgcred))];
-	}			cmsgbuf;
-
-	/*
-	 * The backend doesn't care what we send here, but it wants exactly one
-	 * character to force recvmsg() to block and wait for us.
-	 */
-	buf = '\0';
-	iov.iov_base = &buf;
-	iov.iov_len = 1;
-
-	memset(&msg, 0, sizeof(msg));
-	msg.msg_iov = &iov;
-	msg.msg_iovlen = 1;
-
-	/* We must set up a message that will be filled in by kernel */
-	memset(&cmsgbuf, 0, sizeof(cmsgbuf));
-	msg.msg_control = &cmsgbuf.buf;
-	msg.msg_controllen = sizeof(cmsgbuf.buf);
-	cmsg = CMSG_FIRSTHDR(&msg);
-	cmsg->cmsg_len = CMSG_LEN(sizeof(struct cmsgcred));
-	cmsg->cmsg_level = SOL_SOCKET;
-	cmsg->cmsg_type = SCM_CREDS;
-
-	if (sendmsg(conn->sock, &msg, 0) == -1)
-	{
-		char		sebuf[PG_STRERROR_R_BUFLEN];
-
-		appendPQExpBuffer(&conn->errorMessage,
-						  "pg_local_sendauth: sendmsg: %s\n",
-						  strerror_r(errno, sebuf, sizeof(sebuf)));
-		return STATUS_ERROR;
-	}
-
-	conn->client_finished_auth = true;
-	return STATUS_OK;
-#else
-	libpq_append_conn_error(conn, "SCM_CRED authentication method not supported");
-	return STATUS_ERROR;
-#endif
-}
-
 static int
 pg_password_sendauth(PGconn *conn, const char *password, AuthRequest areq)
 {
@@ -830,8 +768,6 @@ auth_method_description(AuthRequest areq)
 			return libpq_gettext("server requested GSSAPI authentication");
 		case AUTH_REQ_SSPI:
 			return libpq_gettext("server requested SSPI authentication");
-		case AUTH_REQ_SCM_CREDS:
-			return libpq_gettext("server requested UNIX socket credentials");
 		case AUTH_REQ_SASL:
 		case AUTH_REQ_SASL_CONT:
 		case AUTH_REQ_SASL_FIN:
@@ -922,7 +858,6 @@ check_expected_areq(AuthRequest areq, PGconn *conn)
 			case AUTH_REQ_GSS:
 			case AUTH_REQ_GSS_CONT:
 			case AUTH_REQ_SSPI:
-			case AUTH_REQ_SCM_CREDS:
 			case AUTH_REQ_SASL:
 			case AUTH_REQ_SASL_CONT:
 			case AUTH_REQ_SASL_FIN:
@@ -1184,9 +1119,8 @@ pg_fe_sendauth(AuthRequest areq, int payloadlen, PGconn *conn)
 			break;
 
 		case AUTH_REQ_SCM_CREDS:
-			if (pg_local_sendauth(conn) != STATUS_OK)
-				return STATUS_ERROR;
-			break;
+			libpq_append_conn_error(conn, "SCM_CRED authentication method not supported");
+			return STATUS_ERROR;
 
 		default:
 			libpq_append_conn_error(conn, "authentication method %u not supported", areq);
diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
index dd4b98e099..0c197589ab 100644
--- a/src/interfaces/libpq/fe-connect.c
+++ b/src/interfaces/libpq/fe-connect.c
@@ -1333,10 +1333,6 @@ connectOptions2(PGconn *conn)
 				bits |= (1 << AUTH_REQ_SASL_CONT);
 				bits |= (1 << AUTH_REQ_SASL_FIN);
 			}
-			else if (strcmp(method, "creds") == 0)
-			{
-				bits = (1 << AUTH_REQ_SCM_CREDS);
-			}
 			else if (strcmp(method, "none") == 0)
 			{
 				/*
diff --git a/doc/src/sgml/libpq.sgml b/doc/src/sgml/libpq.sgml
index 3706d349ab..9ee5532c07 100644
--- a/doc/src/sgml/libpq.sgml
+++ b/doc/src/sgml/libpq.sgml
@@ -1300,16 +1300,6 @@ postgresql://%2Fvar%2Flib%2Fpostgresql/dbname
           </listitem>
          </varlistentry>
 
-         <varlistentry>
-          <term><literal>creds</literal></term>
-          <listitem>
-           <para>
-            The server must request SCM credential authentication (deprecated
-            as of <productname>PostgreSQL</productname> 9.1).
-           </para>
-          </listitem>
-         </varlistentry>
-
          <varlistentry>
           <term><literal>none</literal></term>
           <listitem>
diff --git a/doc/src/sgml/protocol.sgml b/doc/src/sgml/protocol.sgml
index 73b7f4432f..8b5e7b1ad7 100644
--- a/doc/src/sgml/protocol.sgml
+++ b/doc/src/sgml/protocol.sgml
@@ -315,24 +315,6 @@
       </listitem>
      </varlistentry>
 
-     <varlistentry>
-      <term>AuthenticationSCMCredential</term>
-      <listitem>
-       <para>
-        This response is only possible for local Unix-domain connections
-        on platforms that support SCM credential messages.  The frontend
-        must issue an SCM credential message and then send a single data
-        byte.  (The contents of the data byte are uninteresting; it's
-        only used to ensure that the server waits long enough to receive
-        the credential message.)  If the credential is acceptable,
-        the server responds with an
-        AuthenticationOk, otherwise it responds with an ErrorResponse.
-        (This message type is only issued by pre-9.1 servers.  It may
-        eventually be removed from the protocol specification.)
-       </para>
-      </listitem>
-     </varlistentry>
-
      <varlistentry>
       <term>AuthenticationGSS</term>
       <listitem>
@@ -3449,40 +3431,6 @@ psql "dbname=postgres replication=database" -c "IDENTIFY_SYSTEM;"
     </listitem>
    </varlistentry>
 
-   <varlistentry id="protocol-message-formats-AuthenticationSCMCredential">
-    <term>AuthenticationSCMCredential (B)</term>
-    <listitem>
-     <variablelist>
-      <varlistentry>
-       <term>Byte1('R')</term>
-       <listitem>
-        <para>
-         Identifies the message as an authentication request.
-        </para>
-       </listitem>
-      </varlistentry>
-
-      <varlistentry>
-       <term>Int32(8)</term>
-       <listitem>
-        <para>
-         Length of message contents in bytes, including self.
-        </para>
-       </listitem>
-      </varlistentry>
-
-      <varlistentry>
-       <term>Int32(6)</term>
-       <listitem>
-        <para>
-         Specifies that an SCM credentials message is required.
-        </para>
-       </listitem>
-      </varlistentry>
-     </variablelist>
-    </listitem>
-   </varlistentry>
-
    <varlistentry id="protocol-message-formats-AuthenticationGSS">
     <term>AuthenticationGSS (B)</term>
     <listitem>