| Message ID | 1544571034-25925-1-git-send-email-dave.taht@gmail.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
| Series | Allow class-e address assignment via ifconfig ioctl | expand |
From: Dave Taht <dave.taht@gmail.com> Date: Tue, 11 Dec 2018 15:30:34 -0800 > While most distributions long ago switched to the iproute2 suite > of utilities, which allow class-e (240.0.0.0/4) address assignment, > distributions relying on busybox, toybox and other forms of > ifconfig cannot assign class-e addresses without this kernel patch. > > While CIDR has been obsolete for 2 decades, and a survey of all the > open source code in the world shows the IN_whatever macros are also > obsolete... rather than obsolete CIDR from this ioctl entirely, this > patch merely enables class-e assignment, sanely. > > Signed-off-by: Dave Taht <dave.taht@gmail.com> Applied, thanks Dave.
David Miller <davem@davemloft.net> writes: > From: Dave Taht <dave.taht@gmail.com> > Date: Tue, 11 Dec 2018 15:30:34 -0800 > >> While most distributions long ago switched to the iproute2 suite >> of utilities, which allow class-e (240.0.0.0/4) address assignment, >> distributions relying on busybox, toybox and other forms of >> ifconfig cannot assign class-e addresses without this kernel patch. >> >> While CIDR has been obsolete for 2 decades, and a survey of all the >> open source code in the world shows the IN_whatever macros are also >> obsolete... rather than obsolete CIDR from this ioctl entirely, this >> patch merely enables class-e assignment, sanely. >> >> Signed-off-by: Dave Taht <dave.taht@gmail.com> > > Applied, thanks Dave. Thanks, but... Into what tree did you pull it? it's not in net-next as I speak. I reworked it a bit, giving a hat tip to Vince Fuller and his original patch here: https://lkml.org/lkml/2008/1/7/370 http://www.taht.net/classe/0001-linux-kernel-Allow-class-e-address-assignment-via-ifconfig-ioctl.patch and was minutes away from submitting that version when you took this.
From: Dave Taht <dave@taht.net> Date: Sat, 15 Dec 2018 17:22:52 -0800 > Into what tree did you pull it? it's not in net-next as I speak. It's in the 'net' tree.
diff --git a/include/uapi/linux/in.h b/include/uapi/linux/in.h index 48e8a225b985..eba44371231f 100644 --- a/include/uapi/linux/in.h +++ b/include/uapi/linux/in.h @@ -266,10 +266,14 @@ struct sockaddr_in { #define IN_CLASSD(a) ((((long int) (a)) & 0xf0000000) == 0xe0000000) #define IN_MULTICAST(a) IN_CLASSD(a) -#define IN_MULTICAST_NET 0xF0000000 +#define IN_MULTICAST_NET 0xe0000000 -#define IN_EXPERIMENTAL(a) ((((long int) (a)) & 0xf0000000) == 0xf0000000) -#define IN_BADCLASS(a) IN_EXPERIMENTAL((a)) +#define IN_BADCLASS(a) ((((long int) (a) ) == 0xffffffff) +#define IN_EXPERIMENTAL(a) IN_BADCLASS((a)) + +#define IN_CLASSE(a) ((((long int) (a)) & 0xf0000000) == 0xf0000000) +#define IN_CLASSE_NET 0xffffffff +#define IN_CLASSE_NSHIFT 0 /* Address to accept any incoming messages. */ #define INADDR_ANY ((unsigned long int) 0x00000000) diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c index a34602ae27de..608a6f4223fb 100644 --- a/net/ipv4/devinet.c +++ b/net/ipv4/devinet.c @@ -952,17 +952,18 @@ static int inet_abc_len(__be32 addr) { int rc = -1; /* Something else, probably a multicast. */ - if (ipv4_is_zeronet(addr)) + if (ipv4_is_zeronet(addr) || ipv4_is_lbcast(addr)) rc = 0; else { __u32 haddr = ntohl(addr); - if (IN_CLASSA(haddr)) rc = 8; else if (IN_CLASSB(haddr)) rc = 16; else if (IN_CLASSC(haddr)) rc = 24; + else if (IN_CLASSE(haddr)) + rc = 32; } return rc; diff --git a/net/ipv4/ipconfig.c b/net/ipv4/ipconfig.c index 88212615bf4c..2393e5c106bf 100644 --- a/net/ipv4/ipconfig.c +++ b/net/ipv4/ipconfig.c @@ -429,6 +429,8 @@ static int __init ic_defaults(void) ic_netmask = htonl(IN_CLASSB_NET); else if (IN_CLASSC(ntohl(ic_myaddr))) ic_netmask = htonl(IN_CLASSC_NET); + else if (IN_CLASSE(ntohl(ic_myaddr))) + ic_netmask = htonl(IN_CLASSE_NET); else { pr_err("IP-Config: Unable to guess netmask for address %pI4\n", &ic_myaddr);
While most distributions long ago switched to the iproute2 suite of utilities, which allow class-e (240.0.0.0/4) address assignment, distributions relying on busybox, toybox and other forms of ifconfig cannot assign class-e addresses without this kernel patch. While CIDR has been obsolete for 2 decades, and a survey of all the open source code in the world shows the IN_whatever macros are also obsolete... rather than obsolete CIDR from this ioctl entirely, this patch merely enables class-e assignment, sanely. Signed-off-by: Dave Taht <dave.taht@gmail.com> --- include/uapi/linux/in.h | 10 +++++++--- net/ipv4/devinet.c | 5 +++-- net/ipv4/ipconfig.c | 2 ++ 3 files changed, 12 insertions(+), 5 deletions(-)