Adding upstream version 2.2.1.

Signed-off-by: Daniel Baumann <daniel@debian.org>

staslib/iputil.py

@@ -0,0 +1,169 @@
+# Copyright (c) 2022, Dell Inc. or its subsidiaries.  All rights reserved.
+# SPDX-License-Identifier: Apache-2.0
+# See the LICENSE file for details.
+#
+# This file is part of NVMe STorage Appliance Services (nvme-stas).
+#
+# Authors: Martin Belanger <Martin.Belanger@dell.com>
+
+'''A collection of IP address and network interface utilities'''
+
+import socket
+import logging
+import ipaddress
+from staslib import conf
+
+RTM_NEWADDR = 20
+RTM_GETADDR = 22
+NLM_F_REQUEST = 0x01
+NLM_F_ROOT = 0x100
+NLMSG_DONE = 3
+IFLA_ADDRESS = 1
+NLMSGHDR_SZ = 16
+IFADDRMSG_SZ = 8
+RTATTR_SZ = 4
+
+# Netlink request (Get address command)
+GETADDRCMD = (
+    # BEGIN: struct nlmsghdr
+    b'\0' * 4  # nlmsg_len (placeholder - actual length calculated below)
+    + (RTM_GETADDR).to_bytes(2, byteorder='little', signed=False)  # nlmsg_type
+    + (NLM_F_REQUEST | NLM_F_ROOT).to_bytes(2, byteorder='little', signed=False)  # nlmsg_flags
+    + b'\0' * 2  # nlmsg_seq
+    + b'\0' * 2  # nlmsg_pid
+    # END: struct nlmsghdr
+    + b'\0' * 8  # struct ifaddrmsg
+)
+GETADDRCMD = len(GETADDRCMD).to_bytes(4, byteorder='little') + GETADDRCMD[4:]  # nlmsg_len
+
+
+# ******************************************************************************
+def get_ipaddress_obj(ipaddr):
+    '''@brief Return a IPv4Address or IPv6Address depending on whether @ipaddr
+    is a valid IPv4 or IPv6 address. Return None otherwise.'''
+    try:
+        ip = ipaddress.ip_address(ipaddr)
+    except ValueError:
+        return None
+
+    return ip
+
+
+# ******************************************************************************
+def _data_matches_ip(data_family, data, ip):
+    if data_family == socket.AF_INET:
+        try:
+            other_ip = ipaddress.IPv4Address(data)
+        except ValueError:
+            return False
+        if ip.version == 6:
+            ip = ip.ipv4_mapped
+    elif data_family == socket.AF_INET6:
+        try:
+            other_ip = ipaddress.IPv6Address(data)
+        except ValueError:
+            return False
+        if ip.version == 4:
+            other_ip = other_ip.ipv4_mapped
+    else:
+        return False
+
+    return other_ip == ip
+
+
+# ******************************************************************************
+def iface_of(src_addr):
+    '''@brief Find the interface that has src_addr as one of its assigned IP addresses.
+    @param src_addr: The IP address to match
+    @type src_addr: Instance of ipaddress.IPv4Address or ipaddress.IPv6Address
+    '''
+    with socket.socket(socket.AF_NETLINK, socket.SOCK_RAW) as sock:
+        sock.sendall(GETADDRCMD)
+        nlmsg = sock.recv(8192)
+        nlmsg_idx = 0
+        while True:
+            if nlmsg_idx >= len(nlmsg):
+                nlmsg += sock.recv(8192)
+
+            nlmsg_type = int.from_bytes(nlmsg[nlmsg_idx + 4 : nlmsg_idx + 6], byteorder='little', signed=False)
+            if nlmsg_type == NLMSG_DONE:
+                break
+
+            if nlmsg_type != RTM_NEWADDR:
+                break
+
+            nlmsg_len = int.from_bytes(nlmsg[nlmsg_idx : nlmsg_idx + 4], byteorder='little', signed=False)
+            if nlmsg_len % 4:  # Is msg length not a multiple of 4?
+                break
+
+            ifaddrmsg_indx = nlmsg_idx + NLMSGHDR_SZ
+            ifa_family = nlmsg[ifaddrmsg_indx]
+            ifa_index = int.from_bytes(nlmsg[ifaddrmsg_indx + 4 : ifaddrmsg_indx + 8], byteorder='little', signed=False)
+
+            rtattr_indx = ifaddrmsg_indx + IFADDRMSG_SZ
+            while rtattr_indx < (nlmsg_idx + nlmsg_len):
+                rta_len = int.from_bytes(nlmsg[rtattr_indx : rtattr_indx + 2], byteorder='little', signed=False)
+                rta_type = int.from_bytes(nlmsg[rtattr_indx + 2 : rtattr_indx + 4], byteorder='little', signed=False)
+                if rta_type == IFLA_ADDRESS:
+                    data = nlmsg[rtattr_indx + RTATTR_SZ : rtattr_indx + rta_len]
+                    if _data_matches_ip(ifa_family, data, src_addr):
+                        return socket.if_indextoname(ifa_index)
+
+                rta_len = (rta_len + 3) & ~3  # Round up to multiple of 4
+                rtattr_indx += rta_len  # Move to next rtattr
+
+            nlmsg_idx += nlmsg_len  # Move to next Netlink message
+
+    return ''
+
+
+# ******************************************************************************
+def get_interface(src_addr):
+    '''Get interface for given source address
+    @param src_addr: The source address
+    @type src_addr: str
+    '''
+    if not src_addr:
+        return ''
+
+    src_addr = src_addr.split('%')[0]  # remove scope-id (if any)
+    src_addr = get_ipaddress_obj(src_addr)
+    return '' if src_addr is None else iface_of(src_addr)
+
+
+# ******************************************************************************
+def remove_invalid_addresses(controllers: list):
+    '''@brief Remove controllers with invalid addresses from the list of controllers.
+    @param controllers: List of TIDs
+    '''
+    service_conf = conf.SvcConf()
+    valid_controllers = list()
+    for controller in controllers:
+        if controller.transport in ('tcp', 'rdma'):
+            # Let's make sure that traddr is
+            # syntactically a valid IPv4 or IPv6 address.
+            ip = get_ipaddress_obj(controller.traddr)
+            if ip is None:
+                logging.warning('%s IP address is not valid', controller)
+                continue
+
+            # Let's make sure the address family is enabled.
+            if ip.version not in service_conf.ip_family:
+                logging.debug(
+                    '%s ignored because IPv%s is disabled in %s',
+                    controller,
+                    ip.version,
+                    service_conf.conf_file,
+                )
+                continue
+
+            valid_controllers.append(controller)
+
+        elif controller.transport in ('fc', 'loop'):
+            # At some point, need to validate FC addresses as well...
+            valid_controllers.append(controller)
+
+        else:
+            logging.warning('Invalid transport %s', controller.transport)
+
+    return valid_controllers