From 9dbe6f4ce824aad7ffcaf8cd36be45ebe29dde25 Mon Sep 17 00:00:00 2001 From: DannyAAM Date: Thu, 18 Jan 2018 23:49:28 +0800 Subject: [PATCH] add support for link without MAC (like PPPoE/PPPoA) Signed-off-by: DannyAAM --- networking/udhcp/d6_dhcpc.c | 43 +++++++++++++++++++++++++++++++++---------- networking/udhcp/d6_socket.c | 27 +++++++++++++++++++++++++-- 2 files changed, 58 insertions(+), 12 deletions(-) diff --git a/networking/udhcp/d6_dhcpc.c b/networking/udhcp/d6_dhcpc.c index f4562b0d4..5d456fe54 100644 --- a/networking/udhcp/d6_dhcpc.c +++ b/networking/udhcp/d6_dhcpc.c @@ -1131,7 +1131,8 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv) int timeout; /* must be signed */ unsigned already_waited_sec; unsigned opt; - int retval; + int retval, retval2; + int rand_mac = 0; setup_common_bufsiz(); @@ -1205,15 +1206,15 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv) *colon = ':'; /* restore it for NOMMU reexec */ } - if (d6_read_interface(client_config.interface, + retval2 = d6_read_interface(client_config.interface, &client_config.ifindex, &client6_data.ll_ip6, - client_config.client_mac) - ) { + client_config.client_mac); + if (retval2 != 0 && retval2 != 1) { /* no error, or just lack of MAC is fine */ return 1; } - /* Create client ID based on mac, set clientid_mac_ptr */ + /* Create client ID based on mac (or random, if we don't have it), set clientid_mac_ptr */ { struct d6_option *clientid; clientid = xzalloc(2+2+2+2+6); @@ -1222,7 +1223,12 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv) clientid->data[1] = 3; /* DUID-LL */ clientid->data[3] = 1; /* ethernet */ clientid_mac_ptr = clientid->data + 2+2; - memcpy(clientid_mac_ptr, client_config.client_mac, 6); + if (retval2 == 1) { /* no MAC */ + rand_mac = 1; + /* generate random MAC later (after srand) */ + } else { + memcpy(clientid_mac_ptr, client_config.client_mac, 6); + } client_config.clientid = (void*)clientid; } @@ -1258,6 +1264,12 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv) timeout = 0; already_waited_sec = 0; + /* Generate random MAC here (after srand) */ + if (rand_mac) { + *(uint32_t*)clientid_mac_ptr = rand(); + *(uint32_t*)(clientid_mac_ptr+2) = rand(); + } + /* Main event loop. select() waits on signal pipe and possibly * on sockfd. * "continue" statements in code below jump to the top of the loop. @@ -1308,15 +1320,26 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv) * or if the status of the bridge changed). * Refresh ifindex and client_mac: */ - if (d6_read_interface(client_config.interface, + retval2 = d6_read_interface(client_config.interface, &client_config.ifindex, &client6_data.ll_ip6, - client_config.client_mac) - ) { + client_config.client_mac); + if (retval2 != 0 && retval2 != 1) { /* no error, or just lack of MAC is fine */ goto ret0; /* iface is gone? */ } - memcpy(clientid_mac_ptr, client_config.client_mac, 6); + if (retval2 == 1) { /* no MAC */ + if (rand_mac) { + /* keep original random MAC */ + } else { + rand_mac = 1; + *(uint32_t*)clientid_mac_ptr = rand(); + *(uint32_t*)(clientid_mac_ptr+2) = rand(); + } + } else { + rand_mac = 0; + memcpy(clientid_mac_ptr, client_config.client_mac, 6); + } /* We will restart the wait in any case */ already_waited_sec = 0; diff --git a/networking/udhcp/d6_socket.c b/networking/udhcp/d6_socket.c index d00c217d6..3c9712018 100644 --- a/networking/udhcp/d6_socket.c +++ b/networking/udhcp/d6_socket.c @@ -12,8 +12,10 @@ int FAST_FUNC d6_read_interface(const char *interface, int *ifindex, struct in6_addr *nip6, uint8_t *mac) { - int retval = 3; + int retval = 7; struct ifaddrs *ifap, *ifa; + struct ifreq ifr; + int fd; getifaddrs(&ifap); @@ -31,7 +33,8 @@ int FAST_FUNC d6_read_interface(const char *interface, int *ifindex, struct in6_ log2("MAC %02x:%02x:%02x:%02x:%02x:%02x", mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]); log2("ifindex %d", sll->sll_ifindex); *ifindex = sll->sll_ifindex; - retval &= (0xf - (1<<0)); + retval &= (0xf - (1<<0)); /* MAC */ + retval &= (0xf - (1<<2)); /* ifindex */ } #if 0 if (ifa->ifa_addr->sa_family == AF_INET) { @@ -59,13 +62,33 @@ int FAST_FUNC d6_read_interface(const char *interface, int *ifindex, struct in6_ } freeifaddrs(ifap); + + /* failed to get ifindex getifaddrs (interface without MAC like ppp), try to get ifindex with ioctl */ + if (retval & (1<<2)) { + memset(ifr, 0, sizeof(ifr)); + fd = xsocket(AF_INET6, SOCK_RAW, IPPROTO_RAW); + + strncpy_IFNAMSIZ(ifr->ifr_name, interface); + + if (ioctl(fd, SIOCGIFINDEX, &ifr) == 0) { + *ifindex = ifr.ifr_ifindex; + retval &= (0xf - (1<<2)); /* ifindex */ + } + + close(fd); + } + if (retval == 0) return retval; + if (retval == (1<<0)) /* seems not very critical for just lack of MAC */ + return retval; if (retval & (1<<0)) bb_error_msg("can't get %s", "MAC"); if (retval & (1<<1)) bb_error_msg("can't get %s", "link-local IPv6 address"); + if (retval & (1<<2)) + bb_error_msg("can't get %s", "ifindex"); return -1; } -- 2.15.1