Author: kevans Date: Wed Apr 17 17:18:43 2019 New Revision: 346324 URL: https://svnweb.freebsd.org/changeset/base/346324
Log: net: adjust randomized address bits Give devices that need a MAC a 16-bit allocation out of the FreeBSD Foundation OUI range. Change the name ether_fakeaddr to ether_gen_addr now that we're dealing real MAC addresses with a real OUI rather than random locally-administered addresses. Reviewed by: bz, rgrimes Differential Revision: https://reviews.freebsd.org/D19587 Modified: head/sys/net/ethernet.h head/sys/net/ieee_oui.h head/sys/net/if_bridge.c head/sys/net/if_ethersubr.c head/sys/net/if_vxlan.c Modified: head/sys/net/ethernet.h ============================================================================== --- head/sys/net/ethernet.h Wed Apr 17 17:00:16 2019 (r346323) +++ head/sys/net/ethernet.h Wed Apr 17 17:18:43 2019 (r346324) @@ -422,7 +422,7 @@ void ether_vlan_mtap(struct bpf_if *, struct mbuf *, struct mbuf *ether_vlanencap(struct mbuf *, uint16_t); bool ether_8021q_frame(struct mbuf **mp, struct ifnet *ife, struct ifnet *p, uint16_t vid, uint8_t pcp); -void ether_fakeaddr(struct ether_addr *hwaddr); +void ether_gen_addr(struct ifnet *ifp, struct ether_addr *hwaddr); #ifdef _SYS_EVENTHANDLER_H_ /* new ethernet interface attached event */ Modified: head/sys/net/ieee_oui.h ============================================================================== --- head/sys/net/ieee_oui.h Wed Apr 17 17:00:16 2019 (r346323) +++ head/sys/net/ieee_oui.h Wed Apr 17 17:18:43 2019 (r346324) @@ -67,3 +67,14 @@ /* Allocate 20 bits to bhyve */ #define OUI_FREEBSD_BHYVE_LOW OUI_FREEBSD(0x000001) #define OUI_FREEBSD_BHYVE_HIGH OUI_FREEBSD(0x0fffff) + +/* + * Allocate 16 bits for a pool to give to various interfaces that need a + * generated address, but don't quite need to slice off a whole section of + * the OUI (e.g. cloned interfaces, one-off NICs of various vendors). + * + * ether_gen_addr should be used to generate an address from this pool. + */ +#define OUI_FREEBSD_GENERATED_MASK 0x10ffff +#define OUI_FREEBSD_GENERATED_LOW OUI_FREEBSD(0x100000) +#define OUI_FREEBSD_GENERATED_HIGH OUI_FREEBSD(OU_FREEBSD_GENERATED_MASK) Modified: head/sys/net/if_bridge.c ============================================================================== --- head/sys/net/if_bridge.c Wed Apr 17 17:00:16 2019 (r346323) +++ head/sys/net/if_bridge.c Wed Apr 17 17:18:43 2019 (r346324) @@ -671,7 +671,7 @@ bridge_clone_create(struct if_clone *ifc, int unit, ca getcredhostid(curthread->td_ucred, &hostid); do { if (fb || hostid == 0) { - ether_fakeaddr(&sc->sc_defaddr); + ether_gen_addr(ifp, &sc->sc_defaddr); } else { sc->sc_defaddr.octet[0] = 0x2; sc->sc_defaddr.octet[1] = (hostid >> 24) & 0xff; Modified: head/sys/net/if_ethersubr.c ============================================================================== --- head/sys/net/if_ethersubr.c Wed Apr 17 17:00:16 2019 (r346323) +++ head/sys/net/if_ethersubr.c Wed Apr 17 17:18:43 2019 (r346324) @@ -42,11 +42,13 @@ #include <sys/systm.h> #include <sys/bus.h> #include <sys/eventhandler.h> +#include <sys/jail.h> #include <sys/kernel.h> #include <sys/lock.h> #include <sys/malloc.h> #include <sys/module.h> #include <sys/mbuf.h> +#include <sys/proc.h> #include <sys/priv.h> #include <sys/random.h> #include <sys/socket.h> @@ -54,6 +56,7 @@ #include <sys/sysctl.h> #include <sys/uuid.h> +#include <net/ieee_oui.h> #include <net/if.h> #include <net/if_var.h> #include <net/if_arp.h> @@ -85,6 +88,8 @@ #endif #include <security/mac/mac_framework.h> +#include <crypto/sha1.h> + #ifdef CTASSERT CTASSERT(sizeof (struct ether_header) == ETHER_ADDR_LEN * 2 + 2); CTASSERT(sizeof (struct ether_addr) == ETHER_ADDR_LEN); @@ -1401,19 +1406,37 @@ ether_8021q_frame(struct mbuf **mp, struct ifnet *ife, return (true); } +/* + * Allocate an address from the FreeBSD Foundation OUI. This uses a + * cryptographic hash function on the containing jail's UUID and the interface + * name to attempt to provide a unique but stable address. Pseudo-interfaces + * which require a MAC address should use this function to allocate + * non-locally-administered addresses. + */ void -ether_fakeaddr(struct ether_addr *hwaddr) +ether_gen_addr(struct ifnet *ifp, struct ether_addr *hwaddr) { +#define ETHER_GEN_ADDR_BUFSIZ HOSTUUIDLEN + IFNAMSIZ + 2 + SHA1_CTX ctx; + char buf[ETHER_GEN_ADDR_BUFSIZ]; + char uuid[HOSTUUIDLEN + 1]; + uint64_t addr; + int i, sz; + char digest[SHA1_RESULTLEN]; - /* - * Generate a convenient locally administered address, - * 'bsd' + random 24 low-order bits. 'b' is 0x62, which has the locally - * assigned bit set, and the broadcast/multicast bit clear. - */ - arc4rand(hwaddr->octet, ETHER_ADDR_LEN, 1); - hwaddr->octet[0] = 'b'; - hwaddr->octet[1] = 's'; - hwaddr->octet[2] = 'd'; + getcredhostuuid(curthread->td_ucred, uuid, sizeof(uuid)); + sz = snprintf(buf, ETHER_GEN_ADDR_BUFSIZ, "%s-%s", uuid, ifp->if_xname); + SHA1Init(&ctx); + SHA1Update(&ctx, buf, sz); + SHA1Final(digest, &ctx); + + addr = ((digest[0] << 16) | (digest[1] << 8) | digest[2]) & + OUI_FREEBSD_GENERATED_MASK; + addr = OUI_FREEBSD(addr); + for (i = 0; i < ETHER_ADDR_LEN; ++i) { + hwaddr->octet[i] = addr >> ((ETHER_ADDR_LEN - i - 1) * 8) & + 0xFF; + } } DECLARE_MODULE(ether, ether_mod, SI_SUB_INIT_IF, SI_ORDER_ANY); Modified: head/sys/net/if_vxlan.c ============================================================================== --- head/sys/net/if_vxlan.c Wed Apr 17 17:00:16 2019 (r346323) +++ head/sys/net/if_vxlan.c Wed Apr 17 17:18:43 2019 (r346324) @@ -2754,7 +2754,7 @@ vxlan_clone_create(struct if_clone *ifc, int unit, cad ifmedia_add(&sc->vxl_media, IFM_ETHER | IFM_AUTO, 0, NULL); ifmedia_set(&sc->vxl_media, IFM_ETHER | IFM_AUTO); - ether_fakeaddr(&sc->vxl_hwaddr); + ether_gen_addr(ifp, &sc->vxl_hwaddr); ether_ifattach(ifp, sc->vxl_hwaddr.octet); ifp->if_baudrate = 0; _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
