fdo-mirrors/NetworkManager
1
0
Fork 0
mirror of https://gitlab.freedesktop.org/NetworkManager/NetworkManager.git synced 2026-02-27 10:30:36 +01:00
Code Issues Projects Releases Packages Wiki Activity Actions

core: add nm_utils_create_dhcp_iaid() util

Browse source 
Split out nm_utils_create_dhcp_iaid(), we will need it later.
This is also a re-implementation of systemd's dhcp_identifier_set_iaid().
This commit is contained in:
Thomas Haller 2018-11-23 13:00:07 +01:00
parent 39a1323181
commit 0ae18f0680
3 changed files with 55 additions and 15 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

62
src/nm-core-utils.c
View file

@ -3290,6 +3290,49 @@ nm_utils_hw_addr_gen_stable_eth (NMUtilsStableType stable_type,
/*****************************************************************************/
#define HASH_KEY ((const guint8[16]) { 0x80, 0x11, 0x8c, 0xc2, 0xfe, 0x4a, 0x03, 0xee, 0x3e, 0xd6, 0x0c, 0x6f, 0x36, 0x39, 0x14, 0x09 })
/**
* nm_utils_create_dhcp_iaid:
* @legacy_unstable_byteorder: legacy behavior is to generate a u32 iaid which
* is endianness dependant. This is to preserve backward compatibility.
* For non-legacy behavior, the returned integer is in stable endianness,
* and corresponds to legacy behavior on little endian systems.
* @interface_id: the seed for hashing when generating the ID. Usually,
* this is the interface name.
* @interface_id_len: length of @interface_id
*
* This corresponds to systemd's dhcp_identifier_set_iaid() for generating
* a IAID for the interface.
*
* Returns: the IAID in host byte order. */
guint32
nm_utils_create_dhcp_iaid (gboolean legacy_unstable_byteorder,
const guint8 *interface_id,
gsize interface_id_len)
{
guint64 u64;
guint32 u32;
u64 = c_siphash_hash (HASH_KEY, interface_id, interface_id_len);
u32 = (u64 & 0xffffffffu) ^ (u64 >> 32);
if (legacy_unstable_byteorder) {
/* legacy systemd code dhcp_identifier_set_iaid() generates the iaid
* dependent on the host endianness. Since this function returns the IAID
* in native-byte order, we need to account for that.
*
* On little endian systems, we want the legacy-behavior is identical to
* the endianness-agnostic behavior. So, we need to swap the bytes on
* big-endian systems.
*
* (https://github.com/systemd/systemd/pull/10614). */
return htole32 (u32);
} else {
/* we return the value as-is, in native byte order. */
return u32;
}
}
/**
* nm_utils_dhcp_client_id_systemd_node_specific_full:
* @legacy_unstable_byteorder: historically, the code would generate a iaid
@ -3315,7 +3358,6 @@ nm_utils_dhcp_client_id_systemd_node_specific_full (gboolean legacy_unstable_byt
const guint8 *machine_id,
gsize machine_id_len)
{
const guint8 HASH_KEY[16] = { 0x80, 0x11, 0x8c, 0xc2, 0xfe, 0x4a, 0x03, 0xee, 0x3e, 0xd6, 0x0c, 0x6f, 0x36, 0x39, 0x14, 0x09 };
const guint16 DUID_TYPE_EN = 2;
const guint32 SYSTEMD_PEN = 43793;
struct _nm_packed {
@ -3344,20 +3386,10 @@ nm_utils_dhcp_client_id_systemd_node_specific_full (gboolean legacy_unstable_byt
client_id->type = 255;
u64 = c_siphash_hash (HASH_KEY, interface_id, interface_id_len);
u32 = (u64 & 0xffffffffu) ^ (u64 >> 32);
if (legacy_unstable_byteorder) {
/* original systemd code dhcp_identifier_set_iaid() generates the iaid
* in native endianness. Do that too, to preserve compatibility
* (https://github.com/systemd/systemd/pull/10614). */
u32 = bswap_32 (u32);
} else {
/* generate fixed byteorder, in a way that on little endian systems
* the values agree. Meaning: legacy behavior is identical to this
* on little endian. */
u32 = be32toh (u32);
}
unaligned_write_ne32 (&client_id->iaid, u32);
u32 = nm_utils_create_dhcp_iaid (legacy_unstable_byteorder,
interface_id,
interface_id_len);
unaligned_write_be32 (&client_id->iaid, u32);
unaligned_write_be16 (&client_id->duid.type, DUID_TYPE_EN);

4
src/nm-core-utils.h
View file

@ -376,6 +376,10 @@ char *nm_utils_hw_addr_gen_stable_eth (NMUtilsStableType stable_type,
/*****************************************************************************/
guint32 nm_utils_create_dhcp_iaid (gboolean legacy_unstable_byteorder,
const guint8 *interface_id,
gsize interface_id_len);
GBytes *nm_utils_dhcp_client_id_systemd_node_specific_full (gboolean legacy_unstable_byteorder,
const guint8 *interface_id,
gsize interface_id_len,

4
src/tests/test-general.c
View file

@ -2029,6 +2029,10 @@ test_nm_utils_dhcp_client_id_systemd_node_specific (gconstpointer test_data)
g_assert_cmpmem (&cid[5], 2, &duid_type_en, sizeof (duid_type_en));
g_assert_cmpmem (&cid[7], 4, &systemd_pen, sizeof (systemd_pen));
g_assert_cmpmem (&cid[11], 8, &d->duid_id, sizeof (d->duid_id));
g_assert_cmpint (iaid, ==, htonl (nm_utils_create_dhcp_iaid (legacy_unstable_byteorder,
(const guint8 *) d->ifname,
strlen (d->ifname))));
}
}