network: amend SendOption= to take a c-escaped string

No need to punish users by forcing them to do base64 encodings.

2 files changed, 15 insertions, 12 deletions

diff --git a/man/systemd.network.xml b/man/systemd.network.xml
index 3ef6ff592c..538f4b8e7b 100644
--- a/man/systemd.network.xml
+++ b/man/systemd.network.xml
@@ -1642,10 +1642,14 @@
         <varlistentry>
           <term><varname>SendOption=</varname></term>
           <listitem>
-            <para>Send a raw option with value via DHCPv4 client. Takes a DHCP option and base64 encoded
-            data separated with a colon (option:value). The option ranges [1-254]. This option can be
-            specified multiple times. If an empty string is specified, then all options specified earlier
-            are cleared. Defaults to unset.</para>
+            <para>Send an arbitrary option in the DHCPv4 request. Takes a DHCP option number and an arbitrary
+            data string separated with a colon
+            (<literal><replaceable>option</replaceable>:<replaceable>value</replaceable></literal>). The
+            option number must be an interger in the range 1..254. Special characters in the data string may
+            be escaped using
+            <ulink url="https://en.wikipedia.org/wiki/Escape_sequences_in_C#Table_of_escape_sequences">C-style
+            escapes</ulink>.  This option can be specified multiple times. If an empty string is specified,
+            then all options specified earlier are cleared. Defaults to unset.</para>
           </listitem>
         </varlistentry>
        </variablelist>
diff --git a/src/network/networkd-dhcp4.c b/src/network/networkd-dhcp4.c
index 45091de97d..947853e2c4 100644
--- a/src/network/networkd-dhcp4.c
+++ b/src/network/networkd-dhcp4.c
@@ -6,7 +6,7 @@
 
 #include "alloc-util.h"
 #include "dhcp-client-internal.h"
-#include "hexdecoct.h"
+#include "escape.h"
 #include "hostname-util.h"
 #include "parse-util.h"
 #include "network-internal.h"
@@ -1579,12 +1579,11 @@ int config_parse_dhcp_send_option(
                 void *userdata) {
 
         _cleanup_(sd_dhcp_option_unrefp) sd_dhcp_option *opt = NULL, *old = NULL;
-        _cleanup_free_ char *word = NULL;
-        _cleanup_free_ void *q = NULL;
+        _cleanup_free_ char *word = NULL, *q = NULL;
         Network *network = data;
         const char *p;
         uint8_t u;
-        size_t sz;
+        ssize_t sz;
         int r;
 
         assert(filename);
@@ -1619,10 +1618,10 @@ int config_parse_dhcp_send_option(
                 return 0;
         }
 
-        r = unbase64mem(p, (size_t) -1, &q, &sz);
-        if (r < 0) {
-                log_syntax(unit, LOG_ERR, filename, line, r,
-                           "Failed to decode base64 data, ignoring assignment: %s", p);
+        sz = cunescape(p, 0, &q);
+        if (sz < 0) {
+                log_syntax(unit, LOG_ERR, filename, line, sz,
+                           "Failed to decode option data, ignoring assignment: %s", p);
                 return 0;
         }