From 3b2e7dc5a285edbbb1bf6aed2d88b889d801613f Mon Sep 17 00:00:00 2001 From: Lukas Nykryn Date: Fri, 8 Dec 2023 12:33:06 +0100 Subject: [PATCH] udev: allow/denylist for reading sysfs attributes when composing a NIC name Users can currently pick specific versions of NIC naming, but that does not guarantee that NIC names won't change after the kernel adds a new sysfs attribute. This patch allows for an allow/deny list of sysfs attributes that could be used when composing the name. These lists can be supplied as an hwdb entry in the form of /etc/udev/hwdb.d/50-net-naming-allowlist.hwdb net:naming:drvirtio_net ID_NET_NAME_ALLOW=0 ID_NET_NAME_ALLOW_ACPI_INDEX=1 ID_NET_NAME_ALLOW_ADDR_ASSIGN_TYPE=1 ID_NET_NAME_ALLOW_ADDRESS=1 ID_NET_NAME_ALLOW_ARI_ENABLED=1 ID_NET_NAME_ALLOW_DEV_PORT=1 ID_NET_NAME_ALLOW_FUNCTION_ID=1 ID_NET_NAME_ALLOW_IFLINK=1 ID_NET_NAME_ALLOW_INDEX=1 ID_NET_NAME_ALLOW_LABEL=1 ID_NET_NAME_ALLOW_PHYS_PORT_NAME=1 ID_NET_NAME_ALLOW_TYPE=1 --- man/systemd.net-naming-scheme.xml | 71 +++++++++++++++++++++++++++ rules.d/75-net-description.rules | 2 + src/shared/netif-naming-scheme.c | 81 +++++++++++++++++++++++++++++++ src/shared/netif-naming-scheme.h | 7 +++ src/udev/udev-builtin-net_id.c | 38 +++++++-------- 5 files changed, 180 insertions(+), 19 deletions(-) diff --git a/man/systemd.net-naming-scheme.xml b/man/systemd.net-naming-scheme.xml index e9c00c935dc..63e7d3cc0bb 100644 --- a/man/systemd.net-naming-scheme.xml +++ b/man/systemd.net-naming-scheme.xml @@ -531,6 +531,47 @@ particular version of systemd). + + Limiting the use of specific sysfs attributes + + When creating names for network cards, some naming schemes use data from sysfs populated + by the kernel. This means that although a specific naming scheme in udev is picked, + the network card's name can still change when a new kernel version adds a new sysfs attribute. + For example if kernel starts setting the phys_port_name, udev will append the + "nphys_port_name" suffix to the device name. + + + + ID_NET_NAME_ALLOW=BOOL + + This evironment value sets a fallback policy for reading a sysfs attribute. + If set to 0 udev will not read any sysfs attribute by default, unless it is + explicitly allowlisted, see below. If set to 1 udev can use any sysfs attribute + unless it is explicitly forbidden. The default value is 1. + + + + + + + ID_NET_NAME_ALLOW_sysfsattr=BOOL + + This evironment value explicitly states if udev shall use the specified + sysfsattr, when composing the device name. + + + + + + + With these options, users can set an allowlist or denylist for sysfs attributes. To create + an allowlist, the user needs to set ID_NET_NAME_ALLOW=0 for the device and then list + the allowed attributes with the + ID_NET_NAME_ALLOW_sysfsattr=1 + options. In case of a denylist, the user needs to provide the list of denied attributes with + the ID_NET_NAME_ALLOW_sysfsattr=0 options. + + Examples @@ -617,6 +658,36 @@ ID_NET_NAME_PATH=enp0s29u1u2 ID_NET_NAME_MAC=enx026d3c00000a ID_NET_NAME_PATH=encf5f0 + + + Set an allowlist for reading sysfs attributes for network card naming + + /etc/udev/hwdb.d/50-net-naming-allowlist.hwdb +net:naming:drvirtio_net:* + ID_NET_NAME_ALLOW=0 + ID_NET_NAME_ALLOW_ACPI_INDEX=1 + ID_NET_NAME_ALLOW_ADDR_ASSIGN_TYPE=1 + ID_NET_NAME_ALLOW_ADDRESS=1 + ID_NET_NAME_ALLOW_ARI_ENABLED=1 + ID_NET_NAME_ALLOW_DEV_PORT=1 + ID_NET_NAME_ALLOW_FUNCTION_ID=1 + ID_NET_NAME_ALLOW_IFLINK=1 + ID_NET_NAME_ALLOW_INDEX=1 + ID_NET_NAME_ALLOW_LABEL=1 + ID_NET_NAME_ALLOW_PHYS_PORT_NAME=1 + ID_NET_NAME_ALLOW_TYPE=1 + + + + Set a denylist so that specified sysfs attribute are ignored + + /etc/udev/hwdb.d/50-net-naming-denylist.hwdb +net:naming:drvirtio_net:* + ID_NET_NAME_ALLOW=1 + ID_NET_NAME_ALLOW_DEV_PORT=0 + ID_NET_NAME_ALLOW_PHYS_PORT_NAME=0 + + diff --git a/rules.d/75-net-description.rules b/rules.d/75-net-description.rules index 7e62f8b26b7..5ba70a65450 100644 --- a/rules.d/75-net-description.rules +++ b/rules.d/75-net-description.rules @@ -3,6 +3,8 @@ ACTION=="remove", GOTO="net_end" SUBSYSTEM!="net", GOTO="net_end" +IMPORT{builtin}="hwdb 'net:naming:dr$env{ID_NET_DRIVER}:'" + IMPORT{builtin}="net_id" SUBSYSTEMS=="usb", IMPORT{builtin}="usb_id", IMPORT{builtin}="hwdb --subsystem=usb" diff --git a/src/shared/netif-naming-scheme.c b/src/shared/netif-naming-scheme.c index fbaf5c5a608..38c24760f0a 100644 --- a/src/shared/netif-naming-scheme.c +++ b/src/shared/netif-naming-scheme.c @@ -1,6 +1,9 @@ /* SPDX-License-Identifier: LGPL-2.1-or-later */ +#include "sd-device.h" + #include "alloc-util.h" +#include "device-private.h" #include "netif-naming-scheme.h" #include "proc-cmdline.h" #include "string-util.h" @@ -101,3 +104,81 @@ static const char* const alternative_names_policy_table[_NAMEPOLICY_MAX] = { }; DEFINE_STRING_TABLE_LOOKUP(alternative_names_policy, NamePolicy); + +static int naming_sysattr_allowed_by_default(sd_device *dev) { + int r; + + assert(dev); + + r = device_get_property_bool(dev, "ID_NET_NAME_ALLOW"); + if (r == -ENOENT) + return true; + + return r; +} + +static int naming_sysattr_allowed(sd_device *dev, const char *sysattr) { + char *sysattr_property; + int r; + + assert(dev); + assert(sysattr); + + sysattr_property = strjoina("ID_NET_NAME_ALLOW_", sysattr); + ascii_strupper(sysattr_property); + + r = device_get_property_bool(dev, sysattr_property); + if (r == -ENOENT) + /* If ID_NET_NAME_ALLOW is not set or set to 1 default is to allow */ + return naming_sysattr_allowed_by_default(dev); + + return r; +} + +int device_get_sysattr_int_filtered(sd_device *device, const char *sysattr, int *ret_value) { + int r; + + r = naming_sysattr_allowed(device, sysattr); + if (r < 0) + return r; + if (r == 0) + return -ENOENT; + + return device_get_sysattr_int(device, sysattr, ret_value); +} + +int device_get_sysattr_unsigned_filtered(sd_device *device, const char *sysattr, unsigned *ret_value) { + int r; + + r = naming_sysattr_allowed(device, sysattr); + if (r < 0) + return r; + if (r == 0) + return -ENOENT; + + return device_get_sysattr_unsigned(device, sysattr, ret_value); +} + +int device_get_sysattr_bool_filtered(sd_device *device, const char *sysattr) { + int r; + + r = naming_sysattr_allowed(device, sysattr); + if (r < 0) + return r; + if (r == 0) + return -ENOENT; + + return device_get_sysattr_bool(device, sysattr); +} + +int device_get_sysattr_value_filtered(sd_device *device, const char *sysattr, const char **ret_value) { + int r; + + r = naming_sysattr_allowed(device, sysattr); + if (r < 0) + return r; + if (r == 0) + return -ENOENT; + + return sd_device_get_sysattr_value(device, sysattr, ret_value); +} diff --git a/src/shared/netif-naming-scheme.h b/src/shared/netif-naming-scheme.h index 3f7be088305..62afdc514a9 100644 --- a/src/shared/netif-naming-scheme.h +++ b/src/shared/netif-naming-scheme.h @@ -3,6 +3,8 @@ #include +#include "sd-device.h" + #include "macro.h" /* So here's the deal: net_id is supposed to be an exercise in providing stable names for network devices. However, we @@ -95,3 +97,8 @@ NamePolicy name_policy_from_string(const char *p) _pure_; const char *alternative_names_policy_to_string(NamePolicy p) _const_; NamePolicy alternative_names_policy_from_string(const char *p) _pure_; + +int device_get_sysattr_int_filtered(sd_device *device, const char *sysattr, int *ret_value); +int device_get_sysattr_unsigned_filtered(sd_device *device, const char *sysattr, unsigned *ret_value); +int device_get_sysattr_bool_filtered(sd_device *device, const char *sysattr); +int device_get_sysattr_value_filtered(sd_device *device, const char *sysattr, const char **ret_value); diff --git a/src/udev/udev-builtin-net_id.c b/src/udev/udev-builtin-net_id.c index 91b40088f49..841e4615fcb 100644 --- a/src/udev/udev-builtin-net_id.c +++ b/src/udev/udev-builtin-net_id.c @@ -188,7 +188,7 @@ static int get_dev_port(sd_device *dev, bool fallback_to_dev_id, unsigned *ret) /* Get kernel provided port index for the case when multiple ports on a single PCI function. */ - r = device_get_sysattr_unsigned(dev, "dev_port", &v); + r = device_get_sysattr_unsigned_filtered(dev, "dev_port", &v); if (r < 0) return r; if (r > 0) { @@ -204,7 +204,7 @@ static int get_dev_port(sd_device *dev, bool fallback_to_dev_id, unsigned *ret) if (fallback_to_dev_id) { unsigned iftype; - r = device_get_sysattr_unsigned(dev, "type", &iftype); + r = device_get_sysattr_unsigned_filtered(dev, "type", &iftype); if (r < 0) return r; @@ -212,7 +212,7 @@ static int get_dev_port(sd_device *dev, bool fallback_to_dev_id, unsigned *ret) } if (fallback_to_dev_id) - return device_get_sysattr_unsigned(dev, "dev_id", ret); + return device_get_sysattr_unsigned_filtered(dev, "dev_id", ret); /* Otherwise, return the original index 0. */ *ret = 0; @@ -229,7 +229,7 @@ static int get_port_specifier(sd_device *dev, bool fallback_to_dev_id, char **re assert(ret); /* First, try to use the kernel provided front panel port name for multiple port PCI device. */ - r = sd_device_get_sysattr_value(dev, "phys_port_name", &phys_port_name); + r = device_get_sysattr_value_filtered(dev, "phys_port_name", &phys_port_name); if (r >= 0 && !isempty(phys_port_name)) { if (naming_scheme_has(NAMING_SR_IOV_R)) { int vf_id = -1; @@ -292,10 +292,10 @@ static int pci_get_onboard_index(sd_device *dev, unsigned *ret) { assert(ret); /* ACPI _DSM — device specific method for naming a PCI or PCI Express device */ - r = device_get_sysattr_unsigned(dev, "acpi_index", &idx); + r = device_get_sysattr_unsigned_filtered(dev, "acpi_index", &idx); if (r < 0) /* SMBIOS type 41 — Onboard Devices Extended Information */ - r = device_get_sysattr_unsigned(dev, "index", &idx); + r = device_get_sysattr_unsigned_filtered(dev, "index", &idx); if (r < 0) return log_device_debug_errno(dev, r, "Could not obtain onboard index: %m"); @@ -347,7 +347,7 @@ static int names_pci_onboard_label(sd_device *dev, sd_device *pci_dev, const cha assert(prefix); /* retrieve on-board label from firmware */ - r = sd_device_get_sysattr_value(pci_dev, "label", &label); + r = device_get_sysattr_value_filtered(pci_dev, "label", &label); if (r < 0) return log_device_debug_errno(pci_dev, r, "Failed to get PCI onboard label: %m"); @@ -392,7 +392,7 @@ static int is_pci_multifunction(sd_device *dev) { static bool is_pci_ari_enabled(sd_device *dev) { assert(dev); - return device_get_sysattr_bool(dev, "ari_enabled") > 0; + return device_get_sysattr_bool_filtered(dev, "ari_enabled") > 0; } static bool is_pci_bridge(sd_device *dev) { @@ -400,7 +400,7 @@ static bool is_pci_bridge(sd_device *dev) { assert(dev); - if (sd_device_get_sysattr_value(dev, "modalias", &v) < 0) + if (device_get_sysattr_value_filtered(dev, "modalias", &v) < 0) return false; if (!startswith(v, "pci:")) @@ -442,7 +442,7 @@ static int parse_hotplug_slot_from_function_id(sd_device *dev, int slots_dirfd, return 0; } - if (sd_device_get_sysattr_value(dev, "function_id", &attr) < 0) { + if (device_get_sysattr_value_filtered(dev, "function_id", &attr) < 0) { *ret = 0; return 0; } @@ -505,7 +505,7 @@ static int pci_get_hotplug_slot_from_address( if (!path) return log_oom_debug(); - if (sd_device_get_sysattr_value(pci, path, &address) < 0) + if (device_get_sysattr_value_filtered(pci, path, &address) < 0) continue; /* match slot address with device by stripping the function */ @@ -845,7 +845,7 @@ static int names_devicetree(sd_device *dev, const char *prefix, bool test) { if (!alias_index) continue; - if (sd_device_get_sysattr_value(aliases_dev, alias, &alias_path) < 0) + if (device_get_sysattr_value_filtered(aliases_dev, alias, &alias_path) < 0) continue; if (!path_equal(ofnode_path, alias_path)) @@ -864,7 +864,7 @@ static int names_devicetree(sd_device *dev, const char *prefix, bool test) { } /* ...but make sure we don't have an alias conflict */ - if (i == 0 && sd_device_get_sysattr_value(aliases_dev, conflict, NULL) >= 0) + if (i == 0 && device_get_sysattr_value_filtered(aliases_dev, conflict, NULL) >= 0) return log_device_debug_errno(dev, SYNTHETIC_ERRNO(EEXIST), "Ethernet alias conflict: ethernet and ethernet0 both exist"); @@ -1133,7 +1133,7 @@ static int names_mac(sd_device *dev, const char *prefix, bool test) { assert(dev); assert(prefix); - r = device_get_sysattr_unsigned(dev, "type", &iftype); + r = device_get_sysattr_unsigned_filtered(dev, "type", &iftype); if (r < 0) return log_device_debug_errno(dev, r, "Failed to read 'type' attribute: %m"); @@ -1145,7 +1145,7 @@ static int names_mac(sd_device *dev, const char *prefix, bool test) { "Not generating MAC name for infiniband device."); /* check for NET_ADDR_PERM, skip random MAC addresses */ - r = device_get_sysattr_unsigned(dev, "addr_assign_type", &assign_type); + r = device_get_sysattr_unsigned_filtered(dev, "addr_assign_type", &assign_type); if (r < 0) return log_device_debug_errno(dev, r, "Failed to read/parse addr_assign_type: %m"); @@ -1153,7 +1153,7 @@ static int names_mac(sd_device *dev, const char *prefix, bool test) { return log_device_debug_errno(dev, SYNTHETIC_ERRNO(EINVAL), "addr_assign_type=%u, MAC address is not permanent.", assign_type); - r = sd_device_get_sysattr_value(dev, "address", &s); + r = device_get_sysattr_value_filtered(dev, "address", &s); if (r < 0) return log_device_debug_errno(dev, r, "Failed to read 'address' attribute: %m"); @@ -1203,7 +1203,7 @@ static int names_netdevsim(sd_device *dev, const char *prefix, bool test) { if (r < 0) return log_device_debug_errno(netdevsimdev, r, "Failed to parse device sysnum: %m"); - r = sd_device_get_sysattr_value(dev, "phys_port_name", &phys_port_name); + r = device_get_sysattr_value_filtered(dev, "phys_port_name", &phys_port_name); if (r < 0) return log_device_debug_errno(dev, r, "Failed to get 'phys_port_name' attribute: %m"); if (isempty(phys_port_name)) @@ -1265,7 +1265,7 @@ static int get_ifname_prefix(sd_device *dev, const char **ret) { assert(dev); assert(ret); - r = device_get_sysattr_unsigned(dev, "type", &iftype); + r = device_get_sysattr_unsigned_filtered(dev, "type", &iftype); if (r < 0) return r; @@ -1311,7 +1311,7 @@ static int device_is_stacked(sd_device *dev) { if (r < 0) return r; - r = device_get_sysattr_int(dev, "iflink", &iflink); + r = device_get_sysattr_int_filtered(dev, "iflink", &iflink); if (r < 0) return r;