Rename ident authentication over local connections to peer

This removes an overloading of two authentication options where
one is very secure (peer) and one is often insecure (ident). Peer
is also the name used in libpq from 9.1 to specify the same type
of authentication.

Also make initdb select peer for local connections when ident is
chosen, and ident for TCP connections when peer is chosen.

ident keyword in pg_hba.conf is still accepted and maps to peer
authentication.

1 files changed, 47 insertions, 65 deletions

diff --git a/src/backend/libpq/auth.c b/src/backend/libpq/auth.c
index af43c2a7cbc..5f56020cc76 100644
--- a/src/backend/libpq/auth.c
+++ b/src/backend/libpq/auth.c
@@ -60,7 +60,10 @@ static int	recv_and_check_password_packet(Port *port);
 /* Standard TCP port number for Ident service.	Assigned by IANA */
 #define IDENT_PORT 113
 
-static int	authident(hbaPort *port);
+static int	ident_inet(hbaPort *port);
+#ifdef HAVE_UNIX_SOCKETS
+static int	auth_peer(hbaPort *port);
+#endif
 
 
 /*----------------------------------------------------------------
@@ -269,6 +272,9 @@ auth_failed(Port *port, int status)
 		case uaIdent:
 			errstr = gettext_noop("Ident authentication failed for user \"%s\"");
 			break;
+		case uaPeer:
+			errstr = gettext_noop("Peer authentication failed for user \"%s\"");
+			break;
 		case uaPassword:
 		case uaMD5:
 			errstr = gettext_noop("password authentication failed for user \"%s\"");
@@ -506,11 +512,12 @@ ClientAuthentication(Port *port)
 #endif
 			break;
 
-		case uaIdent:
+		case uaPeer:
+#ifdef HAVE_UNIX_SOCKETS
 
 			/*
-			 * If we are doing ident on unix-domain sockets, use SCM_CREDS
-			 * only if it is defined and SO_PEERCRED isn't.
+			 * If we are doing peer on unix-domain sockets, use SCM_CREDS only
+			 * if it is defined and SO_PEERCRED isn't.
 			 */
 #if !defined(HAVE_GETPEEREID) && !defined(SO_PEERCRED) && \
 	(defined(HAVE_STRUCT_CMSGCRED) || defined(HAVE_STRUCT_FCRED) || \
@@ -535,7 +542,14 @@ ClientAuthentication(Port *port)
 				sendAuthRequest(port, AUTH_REQ_SCM_CREDS);
 			}
 #endif
-			status = authident(port);
+			status = auth_peer(port);
+#else /* HAVE_UNIX_SOCKETS */
+			Assert(false);
+#endif
+			break;
+
+		case uaIdent:
+			status = ident_inet(port);
 			break;
 
 		case uaMD5:
@@ -1599,11 +1613,12 @@ interpret_ident_response(const char *ident_response,
  *
  *	But iff we're unable to get the information from ident, return false.
  */
-static bool
-ident_inet(const SockAddr remote_addr,
-		   const SockAddr local_addr,
-		   char *ident_user)
+static int
+ident_inet(hbaPort *port)
 {
+	const SockAddr remote_addr = port->raddr;
+	const SockAddr local_addr = port->laddr;
+	char		ident_user[IDENT_USERNAME_MAX + 1];
 	pgsocket	sock_fd,		/* File descriptor for socket on which we talk
 								 * to Ident */
 				rc;				/* Return code from a locally called function */
@@ -1646,7 +1661,7 @@ ident_inet(const SockAddr remote_addr,
 	{
 		if (ident_serv)
 			pg_freeaddrinfo_all(hints.ai_family, ident_serv);
-		return false;			/* we don't expect this to happen */
+		return STATUS_ERROR;	/* we don't expect this to happen */
 	}
 
 	hints.ai_flags = AI_NUMERICHOST;
@@ -1662,7 +1677,7 @@ ident_inet(const SockAddr remote_addr,
 	{
 		if (la)
 			pg_freeaddrinfo_all(hints.ai_family, la);
-		return false;			/* we don't expect this to happen */
+		return STATUS_ERROR;	/* we don't expect this to happen */
 	}
 
 	sock_fd = socket(ident_serv->ai_family, ident_serv->ai_socktype,
@@ -1751,7 +1766,11 @@ ident_inet_done:
 		closesocket(sock_fd);
 	pg_freeaddrinfo_all(remote_addr.addr.ss_family, ident_serv);
 	pg_freeaddrinfo_all(local_addr.addr.ss_family, la);
-	return ident_return;
+
+	if (ident_return)
+		/* Success! Check the usermap */
+		return check_usermap(port->hba->usermap, port->user_name, ident_user, false);
+	return STATUS_ERROR;
 }
 
 /*
@@ -1763,9 +1782,12 @@ ident_inet_done:
  */
 #ifdef HAVE_UNIX_SOCKETS
 
-static bool
-ident_unix(int sock, char *ident_user)
+static int
+auth_peer(hbaPort *port)
 {
+	int			sock = port->sock;
+	char		ident_user[IDENT_USERNAME_MAX + 1];
+
 #if defined(HAVE_GETPEEREID)
 	/* OpenBSD style:  */
 	uid_t		uid;
@@ -1779,7 +1801,7 @@ ident_unix(int sock, char *ident_user)
 		ereport(LOG,
 				(errcode_for_socket_access(),
 				 errmsg("could not get peer credentials: %m")));
-		return false;
+		return STATUS_ERROR;
 	}
 
 	pass = getpwuid(uid);
@@ -1789,12 +1811,11 @@ ident_unix(int sock, char *ident_user)
 		ereport(LOG,
 				(errmsg("local user with ID %d does not exist",
 						(int) uid)));
-		return false;
+		return STATUS_ERROR;
 	}
 
 	strlcpy(ident_user, pass->pw_name, IDENT_USERNAME_MAX + 1);
 
-	return true;
 #elif defined(SO_PEERCRED)
 	/* Linux style: use getsockopt(SO_PEERCRED) */
 	struct ucred peercred;
@@ -1809,7 +1830,7 @@ ident_unix(int sock, char *ident_user)
 		ereport(LOG,
 				(errcode_for_socket_access(),
 				 errmsg("could not get peer credentials: %m")));
-		return false;
+		return STATUS_ERROR;
 	}
 
 	pass = getpwuid(peercred.uid);
@@ -1819,12 +1840,11 @@ ident_unix(int sock, char *ident_user)
 		ereport(LOG,
 				(errmsg("local user with ID %d does not exist",
 						(int) peercred.uid)));
-		return false;
+		return STATUS_ERROR;
 	}
 
 	strlcpy(ident_user, pass->pw_name, IDENT_USERNAME_MAX + 1);
 
-	return true;
 #elif defined(HAVE_GETPEERUCRED)
 	/* Solaris > 10 */
 	uid_t		uid;
@@ -1837,7 +1857,7 @@ ident_unix(int sock, char *ident_user)
 		ereport(LOG,
 				(errcode_for_socket_access(),
 				 errmsg("could not get peer credentials: %m")));
-		return false;
+		return STATUS_ERROR;
 	}
 
 	if ((uid = ucred_geteuid(ucred)) == -1)
@@ -1845,7 +1865,7 @@ ident_unix(int sock, char *ident_user)
 		ereport(LOG,
 				(errcode_for_socket_access(),
 		   errmsg("could not get effective UID from peer credentials: %m")));
-		return false;
+		return STATUS_ERROR;
 	}
 
 	ucred_free(ucred);
@@ -1856,12 +1876,11 @@ ident_unix(int sock, char *ident_user)
 		ereport(LOG,
 				(errmsg("local user with ID %d does not exist",
 						(int) uid)));
-		return false;
+		return STATUS_ERROR;
 	}
 
 	strlcpy(ident_user, pass->pw_name, IDENT_USERNAME_MAX + 1);
 
-	return true;
 #elif defined(HAVE_STRUCT_CMSGCRED) || defined(HAVE_STRUCT_FCRED) || (defined(HAVE_STRUCT_SOCKCRED) && defined(LOCAL_CREDS))
 	struct msghdr msg;
 
@@ -1913,7 +1932,7 @@ ident_unix(int sock, char *ident_user)
 		ereport(LOG,
 				(errcode_for_socket_access(),
 				 errmsg("could not get peer credentials: %m")));
-		return false;
+		return STATUS_ERROR;
 	}
 
 	cred = (Cred *) CMSG_DATA(cmsg);
@@ -1925,59 +1944,22 @@ ident_unix(int sock, char *ident_user)
 		ereport(LOG,
 				(errmsg("local user with ID %d does not exist",
 						(int) cred->cruid)));
-		return false;
+		return STATUS_ERROR;
 	}
 
 	strlcpy(ident_user, pw->pw_name, IDENT_USERNAME_MAX + 1);
 
-	return true;
 #else
 	ereport(LOG,
 			(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 			 errmsg("Ident authentication is not supported on local connections on this platform")));
 
-	return false;
-#endif
-}
-#endif   /* HAVE_UNIX_SOCKETS */
-
-
-/*
- *	Determine the username of the initiator of the connection described
- *	by "port".	Then look in the usermap file under the usermap
- *	port->hba->usermap and see if that user is equivalent to Postgres user
- *	port->user.
- *
- *	Return STATUS_OK if yes, STATUS_ERROR if no match (or couldn't get info).
- */
-static int
-authident(hbaPort *port)
-{
-	char		ident_user[IDENT_USERNAME_MAX + 1];
-
-	switch (port->raddr.addr.ss_family)
-	{
-		case AF_INET:
-#ifdef	HAVE_IPV6
-		case AF_INET6:
+	return STATUS_ERROR;
 #endif
-			if (!ident_inet(port->raddr, port->laddr, ident_user))
-				return STATUS_ERROR;
-			break;
-
-#ifdef HAVE_UNIX_SOCKETS
-		case AF_UNIX:
-			if (!ident_unix(port->sock, ident_user))
-				return STATUS_ERROR;
-			break;
-#endif
-
-		default:
-			return STATUS_ERROR;
-	}
 
 	return check_usermap(port->hba->usermap, port->user_name, ident_user, false);
 }
+#endif   /* HAVE_UNIX_SOCKETS */
 
 
 /*----------------------------------------------------------------