From f88a10d65620d97b6d0a7e352a3493c1b7e7409b Mon Sep 17 00:00:00 2001 From: Thomas Graf Date: Sat, 18 Jun 2005 22:50:12 -0700 Subject: [NETLINK]: New message building macros NLMSG_PUT_ANSWER(skb, nlcb, type, length) Start a new netlink message as answer to a request, returns the message header. NLMSG_END(skb, nlh) End a netlink message, fixes total message length, returns skb->len. NLMSG_CANCEL(skb, nlh) Cancel the building process and trim whole message from skb again, returns -1. Signed-off-by: Thomas Graf Signed-off-by: David S. Miller --- include/linux/netlink.h | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-) (limited to 'include/linux/netlink.h') diff --git a/include/linux/netlink.h b/include/linux/netlink.h index b2738ac8bc99..8d1cb419a930 100644 --- a/include/linux/netlink.h +++ b/include/linux/netlink.h @@ -171,8 +171,21 @@ __nlmsg_put(struct sk_buff *skb, u32 pid, u32 seq, int type, int len) } #define NLMSG_PUT(skb, pid, seq, type, len) \ -({ if (skb_tailroom(skb) < (int)NLMSG_SPACE(len)) goto nlmsg_failure; \ - __nlmsg_put(skb, pid, seq, type, len); }) +({ if (skb_tailroom(skb) < (int)NLMSG_SPACE(len)) \ + goto nlmsg_failure; \ + __nlmsg_put(skb, pid, seq, type, len); }) + +#define NLMSG_PUT_ANSWER(skb, cb, type, len) \ + NLMSG_PUT(skb, NETLINK_CB((cb)->skb).pid, \ + (cb)->nlh->nlmsg_seq, type, len) + +#define NLMSG_END(skb, nlh) \ +({ (nlh)->nlmsg_len = (skb)->tail - (unsigned char *) (nlh); \ + (skb)->len; }) + +#define NLMSG_CANCEL(skb, nlh) \ +({ skb_trim(skb, (unsigned char *) (nlh) - (skb)->data); \ + -1; }) extern int netlink_dump_start(struct sock *ssk, struct sk_buff *skb, struct nlmsghdr *nlh, -- cgit v1.2.3 From 1797754ea7ee5e0d859b0a32506ff999f8d5fb71 Mon Sep 17 00:00:00 2001 From: Thomas Graf Date: Sat, 18 Jun 2005 22:53:48 -0700 Subject: [NETLINK]: Introduce NLMSG_NEW macro to better handle netlink flags Introduces a new macro NLMSG_NEW which extends NLMSG_PUT but takes a flags argument. NLMSG_PUT stays there for compatibility but now calls NLMSG_NEW with flags == 0. NLMSG_PUT_ANSWER is renamed to NLMSG_NEW_ANSWER which now also takes a flags argument. Also converts the users of NLMSG_PUT_ANSWER to use NLMSG_NEW_ANSWER and fixes the two direct users of __nlmsg_put to either provide the flags or use NLMSG_NEW(_ANSWER). Signed-off-by: Thomas Graf Signed-off-by: David S. Miller --- include/linux/netlink.h | 17 ++++++++++------- net/core/neighbour.c | 8 ++++---- net/netlink/af_netlink.c | 8 +++++--- 3 files changed, 19 insertions(+), 14 deletions(-) (limited to 'include/linux/netlink.h') diff --git a/include/linux/netlink.h b/include/linux/netlink.h index 8d1cb419a930..e38407a23d04 100644 --- a/include/linux/netlink.h +++ b/include/linux/netlink.h @@ -156,7 +156,7 @@ struct netlink_notify }; static __inline__ struct nlmsghdr * -__nlmsg_put(struct sk_buff *skb, u32 pid, u32 seq, int type, int len) +__nlmsg_put(struct sk_buff *skb, u32 pid, u32 seq, int type, int len, int flags) { struct nlmsghdr *nlh; int size = NLMSG_LENGTH(len); @@ -164,20 +164,23 @@ __nlmsg_put(struct sk_buff *skb, u32 pid, u32 seq, int type, int len) nlh = (struct nlmsghdr*)skb_put(skb, NLMSG_ALIGN(size)); nlh->nlmsg_type = type; nlh->nlmsg_len = size; - nlh->nlmsg_flags = 0; + nlh->nlmsg_flags = flags; nlh->nlmsg_pid = pid; nlh->nlmsg_seq = seq; return nlh; } -#define NLMSG_PUT(skb, pid, seq, type, len) \ +#define NLMSG_NEW(skb, pid, seq, type, len, flags) \ ({ if (skb_tailroom(skb) < (int)NLMSG_SPACE(len)) \ goto nlmsg_failure; \ - __nlmsg_put(skb, pid, seq, type, len); }) + __nlmsg_put(skb, pid, seq, type, len, flags); }) + +#define NLMSG_PUT(skb, pid, seq, type, len) \ + NLMSG_NEW(skb, pid, seq, type, len, 0) -#define NLMSG_PUT_ANSWER(skb, cb, type, len) \ - NLMSG_PUT(skb, NETLINK_CB((cb)->skb).pid, \ - (cb)->nlh->nlmsg_seq, type, len) +#define NLMSG_NEW_ANSWER(skb, cb, type, len, flags) \ + NLMSG_NEW(skb, NETLINK_CB((cb)->skb).pid, \ + (cb)->nlh->nlmsg_seq, type, len, flags) #define NLMSG_END(skb, nlh) \ ({ (nlh)->nlmsg_len = (skb)->tail - (unsigned char *) (nlh); \ diff --git a/net/core/neighbour.c b/net/core/neighbour.c index 2296a145fb78..0fb742e228cc 100644 --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -1590,8 +1590,8 @@ static int neightbl_fill_info(struct neigh_table *tbl, struct sk_buff *skb, struct nlmsghdr *nlh; struct ndtmsg *ndtmsg; - nlh = NLMSG_PUT_ANSWER(skb, cb, RTM_NEWNEIGHTBL, sizeof(struct ndtmsg)); - nlh->nlmsg_flags |= NLM_F_MULTI; + nlh = NLMSG_NEW_ANSWER(skb, cb, RTM_NEWNEIGHTBL, sizeof(struct ndtmsg), + NLM_F_MULTI); ndtmsg = NLMSG_DATA(nlh); @@ -1675,8 +1675,8 @@ static int neightbl_fill_param_info(struct neigh_table *tbl, struct ndtmsg *ndtmsg; struct nlmsghdr *nlh; - nlh = NLMSG_PUT_ANSWER(skb, cb, RTM_NEWNEIGHTBL, sizeof(struct ndtmsg)); - nlh->nlmsg_flags |= NLM_F_MULTI; + nlh = NLMSG_NEW_ANSWER(skb, cb, RTM_NEWNEIGHTBL, sizeof(struct ndtmsg), + NLM_F_MULTI); ndtmsg = NLMSG_DATA(nlh); diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c index e41ce458c2a9..70bcd4744d93 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -1095,8 +1095,7 @@ static int netlink_dump(struct sock *sk) return 0; } - nlh = __nlmsg_put(skb, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq, NLMSG_DONE, sizeof(int)); - nlh->nlmsg_flags |= NLM_F_MULTI; + nlh = NLMSG_NEW_ANSWER(skb, cb, NLMSG_DONE, sizeof(len), NLM_F_MULTI); memcpy(NLMSG_DATA(nlh), &len, sizeof(len)); skb_queue_tail(&sk->sk_receive_queue, skb); sk->sk_data_ready(sk, skb->len); @@ -1107,6 +1106,9 @@ static int netlink_dump(struct sock *sk) netlink_destroy_callback(cb); return 0; + +nlmsg_failure: + return -ENOBUFS; } int netlink_dump_start(struct sock *ssk, struct sk_buff *skb, @@ -1178,7 +1180,7 @@ void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err) } rep = __nlmsg_put(skb, NETLINK_CB(in_skb).pid, nlh->nlmsg_seq, - NLMSG_ERROR, sizeof(struct nlmsgerr)); + NLMSG_ERROR, sizeof(struct nlmsgerr), 0); errmsg = NLMSG_DATA(rep); errmsg->error = err; memcpy(&errmsg->msg, nlh, err ? nlh->nlmsg_len : sizeof(struct nlmsghdr)); -- cgit v1.2.3 From 246955fe4c38bd706ae30e37c64892c94213775d Mon Sep 17 00:00:00 2001 From: Robert Olsson Date: Mon, 20 Jun 2005 13:36:39 -0700 Subject: [NETLINK]: fib_lookup() via netlink Below is a more generic patch to do fib_lookup via netlink. For others we should say that we discussed this as a way to verify route selection. It's also possible there are others uses for this. In short the fist half of struct fib_result_nl is filled in by caller and netlink call fills in the other half and returns it. In case anyone is interested there is a corresponding user app to compare the full routing table this was used to test implementation of the LC-trie. Signed-off-by: David S. Miller --- include/linux/netlink.h | 1 + include/net/ip_fib.h | 14 +++++++++++++ net/ipv4/fib_frontend.c | 55 +++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 70 insertions(+) (limited to 'include/linux/netlink.h') diff --git a/include/linux/netlink.h b/include/linux/netlink.h index e38407a23d04..561d4dc75836 100644 --- a/include/linux/netlink.h +++ b/include/linux/netlink.h @@ -14,6 +14,7 @@ #define NETLINK_SELINUX 7 /* SELinux event notifications */ #define NETLINK_ARPD 8 #define NETLINK_AUDIT 9 /* auditing */ +#define NETLINK_FIB_LOOKUP 10 #define NETLINK_ROUTE6 11 /* af_inet6 route comm channel */ #define NETLINK_IP6_FW 13 #define NETLINK_DNRTMSG 14 /* DECnet routing messages */ diff --git a/include/net/ip_fib.h b/include/net/ip_fib.h index e5a5f6b62f88..a4208a336ac0 100644 --- a/include/net/ip_fib.h +++ b/include/net/ip_fib.h @@ -109,6 +109,20 @@ struct fib_result { #endif }; +struct fib_result_nl { + u32 fl_addr; /* To be looked up*/ + u32 fl_fwmark; + unsigned char fl_tos; + unsigned char fl_scope; + unsigned char tb_id_in; + + unsigned char tb_id; /* Results */ + unsigned char prefixlen; + unsigned char nh_sel; + unsigned char type; + unsigned char scope; + int err; +}; #ifdef CONFIG_IP_ROUTE_MULTIPATH diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c index 563e7d612706..cd8e45ab9580 100644 --- a/net/ipv4/fib_frontend.c +++ b/net/ipv4/fib_frontend.c @@ -516,6 +516,60 @@ static void fib_del_ifaddr(struct in_ifaddr *ifa) #undef BRD1_OK } +static void nl_fib_lookup(struct fib_result_nl *frn, struct fib_table *tb ) +{ + + struct fib_result res; + struct flowi fl = { .nl_u = { .ip4_u = { .daddr = frn->fl_addr, + .fwmark = frn->fl_fwmark, + .tos = frn->fl_tos, + .scope = frn->fl_scope } } }; + if (tb) { + local_bh_disable(); + + frn->tb_id = tb->tb_id; + frn->err = tb->tb_lookup(tb, &fl, &res); + + if (!frn->err) { + frn->prefixlen = res.prefixlen; + frn->nh_sel = res.nh_sel; + frn->type = res.type; + frn->scope = res.scope; + } + local_bh_enable(); + } +} + +static void nl_fib_input(struct sock *sk, int len) +{ + struct sk_buff *skb = NULL; + struct nlmsghdr *nlh = NULL; + struct fib_result_nl *frn; + int err; + u32 pid; + struct fib_table *tb; + + skb = skb_recv_datagram(sk, 0, 0, &err); + nlh = (struct nlmsghdr *)skb->data; + + frn = (struct fib_result_nl *) NLMSG_DATA(nlh); + tb = fib_get_table(frn->tb_id_in); + + nl_fib_lookup(frn, tb); + + pid = nlh->nlmsg_pid; /*pid of sending process */ + NETLINK_CB(skb).groups = 0; /* not in mcast group */ + NETLINK_CB(skb).pid = 0; /* from kernel */ + NETLINK_CB(skb).dst_pid = pid; + NETLINK_CB(skb).dst_groups = 0; /* unicast */ + netlink_unicast(sk, skb, pid, MSG_DONTWAIT); +} + +static void nl_fib_lookup_init(void) +{ + netlink_kernel_create(NETLINK_FIB_LOOKUP, nl_fib_input); +} + static void fib_disable_ip(struct net_device *dev, int force) { if (fib_sync_down(0, dev, force)) @@ -604,6 +658,7 @@ void __init ip_fib_init(void) register_netdevice_notifier(&fib_netdev_notifier); register_inetaddr_notifier(&fib_inetaddr_notifier); + nl_fib_lookup_init(); } EXPORT_SYMBOL(inet_addr_type); -- cgit v1.2.3 From 18b504e25fd617bee8830d2cdcaff7fb7b5931bb Mon Sep 17 00:00:00 2001 From: Alexey Kuznetsov Date: Tue, 21 Jun 2005 12:38:48 -0700 Subject: [NETLINK]: netlink_callback structure needs 5 args not 4 net/ipv4/tcp_diag.c uses up to ->args[4] Signed-off-by: David S. Miller --- include/linux/netlink.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/netlink.h') diff --git a/include/linux/netlink.h b/include/linux/netlink.h index 561d4dc75836..3029cad63a01 100644 --- a/include/linux/netlink.h +++ b/include/linux/netlink.h @@ -147,7 +147,7 @@ struct netlink_callback int (*dump)(struct sk_buff * skb, struct netlink_callback *cb); int (*done)(struct netlink_callback *cb); int family; - long args[4]; + long args[5]; }; struct netlink_notify -- cgit v1.2.3