| /* SPDX-License-Identifier: LGPL-2.1-or-later */ |
| |
| #include <linux/if_infiniband.h> |
| #include <net/ethernet.h> |
| #include <net/if_arp.h> |
| |
| #include "dhcp-identifier.h" |
| #include "netif-util.h" |
| #include "siphash24.h" |
| #include "sparse-endian.h" |
| #include "string-table.h" |
| |
| #define HASH_KEY SD_ID128_MAKE(80,11,8c,c2,fe,4a,03,ee,3e,d6,0c,6f,36,39,14,09) |
| #define APPLICATION_ID SD_ID128_MAKE(a5,0a,d1,12,bf,60,45,77,a2,fb,74,1a,b1,95,5b,03) |
| #define USEC_2000 ((usec_t) 946684800000000) /* 2000-01-01 00:00:00 UTC */ |
| |
| static const char * const duid_type_table[_DUID_TYPE_MAX] = { |
| [DUID_TYPE_LLT] = "DUID-LLT", |
| [DUID_TYPE_EN] = "DUID-EN/Vendor", |
| [DUID_TYPE_LL] = "DUID-LL", |
| [DUID_TYPE_UUID] = "UUID", |
| }; |
| |
| DEFINE_STRING_TABLE_LOOKUP_TO_STRING(duid_type, DUIDType); |
| |
| int dhcp_validate_duid_len(DUIDType duid_type, size_t duid_len, bool strict) { |
| struct duid d; |
| |
| assert_cc(sizeof(d.raw) >= MAX_DUID_LEN); |
| if (duid_len > MAX_DUID_LEN) |
| return -EINVAL; |
| |
| if (!strict) |
| /* Strict validation is not requested. We only ensure that the |
| * DUID is not too long. */ |
| return 0; |
| |
| switch (duid_type) { |
| case DUID_TYPE_LLT: |
| if (duid_len <= sizeof(d.llt)) |
| return -EINVAL; |
| break; |
| case DUID_TYPE_EN: |
| if (duid_len != sizeof(d.en)) |
| return -EINVAL; |
| break; |
| case DUID_TYPE_LL: |
| if (duid_len <= sizeof(d.ll)) |
| return -EINVAL; |
| break; |
| case DUID_TYPE_UUID: |
| if (duid_len != sizeof(d.uuid)) |
| return -EINVAL; |
| break; |
| default: |
| /* accept unknown type in order to be forward compatible */ |
| break; |
| } |
| return 0; |
| } |
| |
| static int dhcp_identifier_set_duid_llt( |
| const struct hw_addr_data *hw_addr, |
| uint16_t arp_type, |
| usec_t t, |
| struct duid *ret_duid, |
| size_t *ret_len) { |
| |
| uint16_t time_from_2000y; |
| |
| assert(hw_addr); |
| assert(ret_duid); |
| assert(ret_len); |
| |
| if (hw_addr->length == 0) |
| return -EOPNOTSUPP; |
| |
| if (arp_type == ARPHRD_ETHER) |
| assert_return(hw_addr->length == ETH_ALEN, -EINVAL); |
| else if (arp_type == ARPHRD_INFINIBAND) |
| assert_return(hw_addr->length == INFINIBAND_ALEN, -EINVAL); |
| else |
| return -EOPNOTSUPP; |
| |
| if (t < USEC_2000) |
| time_from_2000y = 0; |
| else |
| time_from_2000y = (uint16_t) (((t - USEC_2000) / USEC_PER_SEC) & 0xffffffff); |
| |
| unaligned_write_be16(&ret_duid->type, DUID_TYPE_LLT); |
| unaligned_write_be16(&ret_duid->llt.htype, arp_type); |
| unaligned_write_be32(&ret_duid->llt.time, time_from_2000y); |
| memcpy(ret_duid->llt.haddr, hw_addr->bytes, hw_addr->length); |
| |
| *ret_len = offsetof(struct duid, llt.haddr) + hw_addr->length; |
| |
| return 0; |
| } |
| |
| static int dhcp_identifier_set_duid_ll( |
| const struct hw_addr_data *hw_addr, |
| uint16_t arp_type, |
| struct duid *ret_duid, |
| size_t *ret_len) { |
| |
| assert(hw_addr); |
| assert(ret_duid); |
| assert(ret_len); |
| |
| if (hw_addr->length == 0) |
| return -EOPNOTSUPP; |
| |
| if (arp_type == ARPHRD_ETHER) |
| assert_return(hw_addr->length == ETH_ALEN, -EINVAL); |
| else if (arp_type == ARPHRD_INFINIBAND) |
| assert_return(hw_addr->length == INFINIBAND_ALEN, -EINVAL); |
| else |
| return -EOPNOTSUPP; |
| |
| unaligned_write_be16(&ret_duid->type, DUID_TYPE_LL); |
| unaligned_write_be16(&ret_duid->ll.htype, arp_type); |
| memcpy(ret_duid->ll.haddr, hw_addr->bytes, hw_addr->length); |
| |
| *ret_len = offsetof(struct duid, ll.haddr) + hw_addr->length; |
| |
| return 0; |
| } |
| |
| int dhcp_identifier_set_duid_en(bool test_mode, struct duid *ret_duid, size_t *ret_len) { |
| sd_id128_t machine_id; |
| uint64_t hash; |
| int r; |
| |
| assert(ret_duid); |
| assert(ret_len); |
| |
| if (!test_mode) { |
| r = sd_id128_get_machine(&machine_id); |
| if (r < 0) |
| return r; |
| } else |
| /* For tests, especially for fuzzers, reproducibility is important. |
| * Hence, use a static and constant machine ID. |
| * See 9216fddc5a8ac2742e6cfa7660f95c20ca4f2193. */ |
| machine_id = SD_ID128_MAKE(01, 02, 03, 04, 05, 06, 07, 08, 09, 0a, 0b, 0c, 0d, 0e, 0f, 10); |
| |
| unaligned_write_be16(&ret_duid->type, DUID_TYPE_EN); |
| unaligned_write_be32(&ret_duid->en.pen, SYSTEMD_PEN); |
| |
| /* a bit of snake-oil perhaps, but no need to expose the machine-id |
| * directly; duid->en.id might not be aligned, so we need to copy */ |
| hash = htole64(siphash24(&machine_id, sizeof(machine_id), HASH_KEY.bytes)); |
| memcpy(ret_duid->en.id, &hash, sizeof(ret_duid->en.id)); |
| |
| *ret_len = offsetof(struct duid, en.id) + sizeof(ret_duid->en.id); |
| |
| if (test_mode) |
| assert_se(memcmp(ret_duid, (const uint8_t[]) { 0x00, 0x02, 0x00, 0x00, 0xab, 0x11, 0x61, 0x77, 0x40, 0xde, 0x13, 0x42, 0xc3, 0xa2 }, *ret_len) == 0); |
| |
| return 0; |
| } |
| |
| static int dhcp_identifier_set_duid_uuid(struct duid *ret_duid, size_t *ret_len) { |
| sd_id128_t machine_id; |
| int r; |
| |
| assert(ret_duid); |
| assert(ret_len); |
| |
| r = sd_id128_get_machine_app_specific(APPLICATION_ID, &machine_id); |
| if (r < 0) |
| return r; |
| |
| unaligned_write_be16(&ret_duid->type, DUID_TYPE_UUID); |
| memcpy(&ret_duid->uuid.uuid, &machine_id, sizeof(machine_id)); |
| |
| *ret_len = offsetof(struct duid, uuid.uuid) + sizeof(machine_id); |
| |
| return 0; |
| } |
| |
| int dhcp_identifier_set_duid( |
| DUIDType duid_type, |
| const struct hw_addr_data *hw_addr, |
| uint16_t arp_type, |
| usec_t llt_time, |
| bool test_mode, |
| struct duid *ret_duid, |
| size_t *ret_len) { |
| |
| switch (duid_type) { |
| case DUID_TYPE_LLT: |
| return dhcp_identifier_set_duid_llt(hw_addr, arp_type, llt_time, ret_duid, ret_len); |
| case DUID_TYPE_EN: |
| return dhcp_identifier_set_duid_en(test_mode, ret_duid, ret_len); |
| case DUID_TYPE_LL: |
| return dhcp_identifier_set_duid_ll(hw_addr, arp_type, ret_duid, ret_len); |
| case DUID_TYPE_UUID: |
| return dhcp_identifier_set_duid_uuid(ret_duid, ret_len); |
| default: |
| return -EINVAL; |
| } |
| } |
| |
| int dhcp_identifier_set_iaid( |
| sd_device *dev, |
| const struct hw_addr_data *hw_addr, |
| bool legacy_unstable_byteorder, |
| void *ret) { |
| |
| const char *name = NULL; |
| uint32_t id32; |
| uint64_t id; |
| |
| assert(hw_addr); |
| assert(ret); |
| |
| if (dev) |
| name = net_get_persistent_name(dev); |
| if (name) |
| id = siphash24(name, strlen(name), HASH_KEY.bytes); |
| else |
| /* fall back to MAC address if no predictable name available */ |
| id = siphash24(hw_addr->bytes, hw_addr->length, HASH_KEY.bytes); |
| |
| id32 = (id & 0xffffffff) ^ (id >> 32); |
| |
| if (legacy_unstable_byteorder) |
| /* for historical reasons (a bug), the bits were swapped and thus |
| * the result was endianness dependent. Preserve that behavior. */ |
| id32 = bswap_32(id32); |
| else |
| /* the fixed behavior returns a stable byte order. Since LE is expected |
| * to be more common, swap the bytes on LE to give the same as legacy |
| * behavior. */ |
| id32 = be32toh(id32); |
| |
| unaligned_write_ne32(ret, id32); |
| return 0; |
| } |