dhcp/SOURCES/0016-Turn-on-creating-sendi...

127 lines
3.4 KiB
Diff

From 2f6b827e89305adcff45288c632785ac054adb8e Mon Sep 17 00:00:00 2001
From: Pavel Zhukov <pzhukov@redhat.com>
Date: Thu, 21 Feb 2019 10:36:30 +0100
Subject: [PATCH 16/26] Turn on creating/sending of DUID
Cc: pzhukov@redhat.com
as client identifier with DHCPv4 clients (#560361c#40, rfc4361)
---
client/dhclient.c | 74 ++++++++++++++++++++++++++++++++++++++++++++++++++++---
1 file changed, 70 insertions(+), 4 deletions(-)
diff --git a/client/dhclient.c b/client/dhclient.c
index 8e57da9..ccc98e4 100644
--- a/client/dhclient.c
+++ b/client/dhclient.c
@@ -4021,6 +4021,59 @@ write_options(struct client_state *client, struct option_state *options,
}
}
+int unhexchar(char c) {
+
+ if (c >= '0' && c <= '9')
+ return c - '0';
+
+ if (c >= 'a' && c <= 'f')
+ return c - 'a' + 10;
+
+ if (c >= 'A' && c <= 'F')
+ return c - 'A' + 10;
+
+ return -1;
+}
+
+isc_result_t
+read_uuid(u_int8_t* uuid) {
+ const char *id_fname = "/etc/machine-id";
+ char id[32];
+ size_t nread;
+ FILE * file = fopen( id_fname , "r");
+ if (!file) {
+ log_debug("Cannot open %s", id_fname);
+ return ISC_R_IOERROR;
+ }
+ nread = fread(id, 1, sizeof id, file);
+ fclose(file);
+
+ if (nread < 32) {
+ log_debug("Not enough data in %s", id_fname);
+ return ISC_R_IOERROR;
+ }
+ int j;
+ for (j = 0; j < 16; j++) {
+ int a, b;
+
+ a = unhexchar(id[j*2]);
+ b = unhexchar(id[j*2+1]);
+
+ if (a < 0 || b < 0) {
+ log_debug("Wrong data in %s", id_fname);
+ return ISC_R_IOERROR;
+ }
+ uuid[j] = a << 4 | b;
+ }
+
+ /* Set UUID version to 4 --- truly random generation */
+ uuid[6] = (uuid[6] & 0x0F) | 0x40;
+ /* Set the UUID variant to DCE */
+ uuid[8] = (uuid[8] & 0x3F) | 0x80;
+
+ return ISC_R_SUCCESS;
+}
+
/*
* The "best" default DUID, since we cannot predict any information
* about the system (such as whether or not the hardware addresses are
@@ -4041,6 +4094,7 @@ form_duid(struct data_string *duid, const char *file, int line)
struct interface_info *ip;
int len;
char *str;
+ u_int8_t uuid[16];
/* For now, just use the first interface on the list. */
ip = interfaces;
@@ -4061,9 +4115,16 @@ form_duid(struct data_string *duid, const char *file, int line)
(ip->hw_address.hlen > sizeof(ip->hw_address.hbuf)))
log_fatal("Impossible hardware address length at %s:%d.", MDL);
- if (duid_type == 0)
- duid_type = stateless ? DUID_LL : DUID_LLT;
-
+ if (duid_type == 0) {
+ if (read_uuid(uuid) == ISC_R_SUCCESS)
+ duid_type = DUID_UUID;
+ else
+ duid_type = stateless ? DUID_LL : DUID_LLT;
+ }
+
+ if (duid_type == DUID_UUID)
+ len = 2 + sizeof (uuid);
+ else {
/*
* 2 bytes for the 'duid type' field.
* 2 bytes for the 'htype' field.
@@ -4074,13 +4135,18 @@ form_duid(struct data_string *duid, const char *file, int line)
len = 4 + (ip->hw_address.hlen - 1);
if (duid_type == DUID_LLT)
len += 4;
+ }
if (!buffer_allocate(&duid->buffer, len, MDL))
log_fatal("no memory for default DUID!");
duid->data = duid->buffer->data;
duid->len = len;
+ if (duid_type == DUID_UUID) {
+ putUShort(duid->buffer->data, DUID_UUID);
+ memcpy(duid->buffer->data + 2, uuid, sizeof(uuid));
+ }
/* Basic Link Local Address type of DUID. */
- if (duid_type == DUID_LLT) {
+ else if (duid_type == DUID_LLT) {
putUShort(duid->buffer->data, DUID_LLT);
putUShort(duid->buffer->data + 2, ip->hw_address.hbuf[0]);
putULong(duid->buffer->data + 4, cur_time - DUID_TIME_EPOCH);
--
2.14.5