Make domain name length settable, use reference in DhcpRepr

Cargo.toml

@@ -249,6 +249,10 @@ dns-max-name-size-64 = []
 dns-max-name-size-128 = []
 dns-max-name-size-255 = [] # Default
 
+dhcp-max-domain-name-size-32 = []
+dhcp-max-domain-name-size-64 = [] # Default
+dhcp-max-domain-name-size-128 = []
+
 rpl-relations-buffer-count-1 = []
 rpl-relations-buffer-count-2 = []
 rpl-relations-buffer-count-4 = []

build.rs

@@ -19,6 +19,7 @@ static CONFIGS: &[(&str, usize)] = &[
     ("DNS_MAX_RESULT_COUNT", 1),
     ("DNS_MAX_SERVER_COUNT", 1),
     ("DNS_MAX_NAME_SIZE", 255),
+    ("DHCP_MAX_DOMAIN_NAME_SIZE", 64),
     ("RPL_RELATIONS_BUFFER_COUNT", 16),
     ("RPL_PARENTS_BUFFER_COUNT", 8),
     // END AUTOGENERATED CONFIG FEATURES

gen_config.py

@@ -40,6 +40,7 @@ def feature(name, default, min, max, pow2=None):
 feature("dns_max_result_count", default=1, min=1, max=32, pow2=4)
 feature("dns_max_server_count", default=1, min=1, max=32, pow2=4)
 feature("dns_max_name_size", default=255, min=64, max=255, pow2=True)
+feature("dhcp_max_domain_name_size", default=64, min=32, max=255, pow2=True)
 feature("rpl_relations_buffer_count", default=16, min=1, max=128, pow2=True)
 feature("rpl_parents_buffer_count", default=8, min=2, max=32, pow2=True)
 

src/lib.rs

@@ -136,6 +136,7 @@ pub mod config {
     pub const DNS_MAX_NAME_SIZE: usize = 255;
     pub const DNS_MAX_RESULT_COUNT: usize = 1;
     pub const DNS_MAX_SERVER_COUNT: usize = 1;
+    pub const DHCP_MAX_DOMAIN_NAME_SIZE: usize = 64;
     pub const FRAGMENTATION_BUFFER_SIZE: usize = 1500;
     pub const IFACE_MAX_ADDR_COUNT: usize = 8;
     pub const IFACE_MAX_MULTICAST_GROUP_COUNT: usize = 4;

src/socket/dhcpv4.rs

@@ -1,13 +1,14 @@
+use core::str::FromStr;
 #[cfg(feature = "async")]
 use core::task::Waker;
 
+use crate::config::DHCP_MAX_DOMAIN_NAME_SIZE;
 use crate::iface::Context;
 use crate::time::{Duration, Instant};
 use crate::wire::dhcpv4::field as dhcpv4_field;
 use crate::wire::{
     DhcpMessageType, DhcpPacket, DhcpRepr, IpAddress, IpProtocol, Ipv4Address, Ipv4Cidr, Ipv4Repr,
-    UdpRepr, DHCP_CLIENT_PORT, DHCP_MAX_DNS_SERVER_COUNT, DHCP_MAX_DOMAIN_NAME_LEN,
-    DHCP_SERVER_PORT, UDP_HEADER_LEN,
+    UdpRepr, DHCP_CLIENT_PORT, DHCP_MAX_DNS_SERVER_COUNT, DHCP_SERVER_PORT, UDP_HEADER_LEN,
 };
 use crate::wire::{DhcpOption, HardwareAddress};
 use heapless::{String, Vec};
@@ -41,7 +42,7 @@ pub struct Config<'a> {
     /// DNS servers
     pub dns_servers: Vec<Ipv4Address, DHCP_MAX_DNS_SERVER_COUNT>,
     /// Domain name
-    pub domain_name: Option<String<DHCP_MAX_DOMAIN_NAME_LEN>>,
+    pub domain_name: Option<String<DHCP_MAX_DOMAIN_NAME_SIZE>>,
     /// Received DHCP packet
     pub packet: Option<DhcpPacket<&'a [u8]>>,
 }
@@ -498,7 +499,10 @@ impl<'a> Socket<'a> {
             address: Ipv4Cidr::new(dhcp_repr.your_ip, prefix_len),
             router: dhcp_repr.router,
             dns_servers,
-            domain_name: dhcp_repr.domain_name.clone(),
+            domain_name: dhcp_repr
+                .domain_name
+                .map(String::from_str)
+                .and_then(Result::ok),
             packet: None,
         };
 
@@ -1004,7 +1008,7 @@ mod test {
             router: Some(SERVER_IP),
             subnet_mask: Some(MASK_24),
             dns_servers: Some(Vec::from_slice(DNS_IPS).unwrap()),
-            domain_name: Some(String::from_str(DOMAIN_NAME).unwrap()),
+            domain_name: Some(DOMAIN_NAME),
             lease_duration: Some(1000),
 
             ..DHCP_DEFAULT
@@ -1032,7 +1036,7 @@ mod test {
             router: Some(SERVER_IP),
             subnet_mask: Some(MASK_24),
             dns_servers: Some(Vec::from_slice(DNS_IPS).unwrap()),
-            domain_name: Some(String::from_str(DOMAIN_NAME).unwrap()),
+            domain_name: Some(DOMAIN_NAME),
             lease_duration: Some(1000),
 
             ..DHCP_DEFAULT

src/wire/dhcpv4.rs

@@ -3,7 +3,7 @@
 use bitflags::bitflags;
 use byteorder::{ByteOrder, NetworkEndian};
 use core::iter;
-use heapless::{String, Vec};
+use heapless::Vec;
 
 use super::{Error, Result};
 use crate::wire::arp::Hardware;
@@ -649,7 +649,7 @@ pub struct Repr<'a> {
     /// DNS servers
     pub dns_servers: Option<Vec<Ipv4Address, MAX_DNS_SERVER_COUNT>>,
     /// Domain name
-    pub domain_name: Option<String<MAX_DOMAIN_NAME_LEN>>,
+    pub domain_name: Option<&'a str>,
     /// The maximum size dhcp packet the interface can receive
     pub max_size: Option<u16>,
     /// The DHCP IP lease duration, specified in seconds.
@@ -697,7 +697,7 @@ impl<'a> Repr<'a> {
         }
         if let Some(domain_name) = &self.domain_name {
             len += 2;
-            len += domain_name.len();
+            len += domain_name.as_bytes().len();
         }
         if let Some(list) = self.parameter_request_list {
             len += list.len() + 2;
@@ -811,13 +811,8 @@ impl<'a> Repr<'a> {
                     }
                 }
                 (field::OPT_DOMAIN_NAME, _) => {
-                    let mut name = String::new();
-
-                    if let Ok(n) = core::str::from_utf8(data) {
-                        if data.len() <= MAX_DOMAIN_NAME_LEN {
-                            name.push_str(n).ok();
-                            domain_name = Some(name);
-                        }
+                    if let Ok(name) = core::str::from_utf8(data) {
+                        domain_name = Some(name);
                     }
                 }
                 _ => {}