kernel: deprecate Internet Class A/B/C

Hide historical Class A/B/C macros unless IN_HISTORICAL_NETS is defined;
define it for user level.  Define IN_MULTICAST separately from IN_CLASSD,
and use it in pf instead of IN_CLASSD.  Stop using class for setting
default masks when not specified; instead, define new default mask
(24 bits).  Warn when an Internet address is set without a mask.

MFC after:	1 month
Reviewed by:	cy
Differential Revision: https://reviews.freebsd.org/D32708
This commit is contained in:
Mike Karels 2021-10-26 22:01:09 -05:00 committed by Sebastian Huber
parent 73784208e3
commit a9a87c1921
1 changed files with 17 additions and 5 deletions

View File

@ -342,10 +342,15 @@ __END_DECLS
#define IPPORT_MAX 65535
/*
* Definitions of bits in internet address integers.
* On subnets, the decomposition of addresses to host and net parts
* is done according to subnet mask, not the masks here.
* Historical definitions of bits in internet address integers
* (pre-CIDR). Class A/B/C are long obsolete, and now deprecated.
* Hide these definitions from the kernel unless IN_HISTORICAL_NETS
* is defined. Provide the historical definitions to user level for now.
*/
#ifndef _KERNEL
#define IN_HISTORICAL_NETS
#endif
#ifdef IN_HISTORICAL_NETS
#define IN_CLASSA(i) (((in_addr_t)(i) & 0x80000000) == 0)
#define IN_CLASSA_NET 0xff000000
#define IN_CLASSA_NSHIFT 24
@ -362,12 +367,17 @@ __END_DECLS
#define IN_CLASSC_NET 0xffffff00
#define IN_CLASSC_NSHIFT 8
#define IN_CLASSC_HOST 0x000000ff
#endif /* IN_HISTORICAL_NETS */
#define IN_CLASSD(i) (((in_addr_t)(i) & 0xf0000000) == 0xe0000000)
#define IN_NETMASK_DEFAULT 0xffffff00 /* mask when forced to guess */
#define IN_MULTICAST(i) (((in_addr_t)(i) & 0xf0000000) == 0xe0000000)
#ifdef IN_HISTORICAL_NETS
#define IN_CLASSD(i) IN_MULTICAST(i)
#define IN_CLASSD_NET 0xf0000000 /* These ones aren't really */
#define IN_CLASSD_NSHIFT 28 /* net and host fields, but */
#define IN_CLASSD_HOST 0x0fffffff /* routing needn't know. */
#define IN_MULTICAST(i) IN_CLASSD(i)
#endif /* IN_HISTORICAL_NETS */
#define IN_EXPERIMENTAL(i) (((in_addr_t)(i) & 0xf0000000) == 0xf0000000)
#define IN_BADCLASS(i) (((in_addr_t)(i) & 0xf0000000) == 0xf0000000)
@ -398,7 +408,9 @@ __END_DECLS
#define INADDR_ALLMDNS_GROUP ((in_addr_t)0xe00000fb) /* 224.0.0.251 */
#define INADDR_MAX_LOCAL_GROUP ((in_addr_t)0xe00000ff) /* 224.0.0.255 */
#ifdef IN_HISTORICAL_NETS
#define IN_LOOPBACKNET 127 /* official! */
#endif /* IN_HISTORICAL_NETS */
#define IN_RFC3021_MASK ((in_addr_t)0xfffffffe)