1 #include <linux/mutex.h> 2 #include <linux/socket.h> 3 #include <linux/skbuff.h> 4 #include <net/netlink.h> 5 #include <net/net_namespace.h> 6 #include <linux/module.h> 7 #include <net/sock.h> 8 9 #include <linux/inet_diag.h> 10 #include <linux/sock_diag.h> 11 12 static const struct sock_diag_handler *sock_diag_handlers[AF_MAX]; 13 static int (*inet_rcv_compat)(struct sk_buff *skb, struct nlmsghdr *nlh); 14 static DEFINE_MUTEX(sock_diag_table_mutex); 15 16 int sock_diag_check_cookie(void *sk, __u32 *cookie) 17 { 18 if ((cookie[0] != INET_DIAG_NOCOOKIE || 19 cookie[1] != INET_DIAG_NOCOOKIE) && 20 ((u32)(unsigned long)sk != cookie[0] || 21 (u32)((((unsigned long)sk) >> 31) >> 1) != cookie[1])) 22 return -ESTALE; 23 else 24 return 0; 25 } 26 EXPORT_SYMBOL_GPL(sock_diag_check_cookie); 27 28 void sock_diag_save_cookie(void *sk, __u32 *cookie) 29 { 30 cookie[0] = (u32)(unsigned long)sk; 31 cookie[1] = (u32)(((unsigned long)sk >> 31) >> 1); 32 } 33 EXPORT_SYMBOL_GPL(sock_diag_save_cookie); 34 35 int sock_diag_put_meminfo(struct sock *sk, struct sk_buff *skb, int attrtype) 36 { 37 u32 mem[SK_MEMINFO_VARS]; 38 39 mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk); 40 mem[SK_MEMINFO_RCVBUF] = sk->sk_rcvbuf; 41 mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk); 42 mem[SK_MEMINFO_SNDBUF] = sk->sk_sndbuf; 43 mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc; 44 mem[SK_MEMINFO_WMEM_QUEUED] = sk->sk_wmem_queued; 45 mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc); 46 mem[SK_MEMINFO_BACKLOG] = sk->sk_backlog.len; 47 48 return nla_put(skb, attrtype, sizeof(mem), &mem); 49 } 50 EXPORT_SYMBOL_GPL(sock_diag_put_meminfo); 51 52 void sock_diag_register_inet_compat(int (*fn)(struct sk_buff *skb, struct nlmsghdr *nlh)) 53 { 54 mutex_lock(&sock_diag_table_mutex); 55 inet_rcv_compat = fn; 56 mutex_unlock(&sock_diag_table_mutex); 57 } 58 EXPORT_SYMBOL_GPL(sock_diag_register_inet_compat); 59 60 void sock_diag_unregister_inet_compat(int (*fn)(struct sk_buff *skb, struct nlmsghdr *nlh)) 61 { 62 mutex_lock(&sock_diag_table_mutex); 63 inet_rcv_compat = NULL; 64 mutex_unlock(&sock_diag_table_mutex); 65 } 66 EXPORT_SYMBOL_GPL(sock_diag_unregister_inet_compat); 67 68 int sock_diag_register(const struct sock_diag_handler *hndl) 69 { 70 int err = 0; 71 72 if (hndl->family >= AF_MAX) 73 return -EINVAL; 74 75 mutex_lock(&sock_diag_table_mutex); 76 if (sock_diag_handlers[hndl->family]) 77 err = -EBUSY; 78 else 79 sock_diag_handlers[hndl->family] = hndl; 80 mutex_unlock(&sock_diag_table_mutex); 81 82 return err; 83 } 84 EXPORT_SYMBOL_GPL(sock_diag_register); 85 86 void sock_diag_unregister(const struct sock_diag_handler *hnld) 87 { 88 int family = hnld->family; 89 90 if (family >= AF_MAX) 91 return; 92 93 mutex_lock(&sock_diag_table_mutex); 94 BUG_ON(sock_diag_handlers[family] != hnld); 95 sock_diag_handlers[family] = NULL; 96 mutex_unlock(&sock_diag_table_mutex); 97 } 98 EXPORT_SYMBOL_GPL(sock_diag_unregister); 99 100 static const inline struct sock_diag_handler *sock_diag_lock_handler(int family) 101 { 102 if (sock_diag_handlers[family] == NULL) 103 request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK, 104 NETLINK_SOCK_DIAG, family); 105 106 mutex_lock(&sock_diag_table_mutex); 107 return sock_diag_handlers[family]; 108 } 109 110 static inline void sock_diag_unlock_handler(const struct sock_diag_handler *h) 111 { 112 mutex_unlock(&sock_diag_table_mutex); 113 } 114 115 static int __sock_diag_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh) 116 { 117 int err; 118 struct sock_diag_req *req = nlmsg_data(nlh); 119 const struct sock_diag_handler *hndl; 120 121 if (nlmsg_len(nlh) < sizeof(*req)) 122 return -EINVAL; 123 124 hndl = sock_diag_lock_handler(req->sdiag_family); 125 if (hndl == NULL) 126 err = -ENOENT; 127 else 128 err = hndl->dump(skb, nlh); 129 sock_diag_unlock_handler(hndl); 130 131 return err; 132 } 133 134 static int sock_diag_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh) 135 { 136 int ret; 137 138 switch (nlh->nlmsg_type) { 139 case TCPDIAG_GETSOCK: 140 case DCCPDIAG_GETSOCK: 141 if (inet_rcv_compat == NULL) 142 request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK, 143 NETLINK_SOCK_DIAG, AF_INET); 144 145 mutex_lock(&sock_diag_table_mutex); 146 if (inet_rcv_compat != NULL) 147 ret = inet_rcv_compat(skb, nlh); 148 else 149 ret = -EOPNOTSUPP; 150 mutex_unlock(&sock_diag_table_mutex); 151 152 return ret; 153 case SOCK_DIAG_BY_FAMILY: 154 return __sock_diag_rcv_msg(skb, nlh); 155 default: 156 return -EINVAL; 157 } 158 } 159 160 static DEFINE_MUTEX(sock_diag_mutex); 161 162 static void sock_diag_rcv(struct sk_buff *skb) 163 { 164 mutex_lock(&sock_diag_mutex); 165 netlink_rcv_skb(skb, &sock_diag_rcv_msg); 166 mutex_unlock(&sock_diag_mutex); 167 } 168 169 static int __net_init diag_net_init(struct net *net) 170 { 171 struct netlink_kernel_cfg cfg = { 172 .input = sock_diag_rcv, 173 }; 174 175 net->diag_nlsk = netlink_kernel_create(net, NETLINK_SOCK_DIAG, 176 THIS_MODULE, &cfg); 177 return net->diag_nlsk == NULL ? -ENOMEM : 0; 178 } 179 180 static void __net_exit diag_net_exit(struct net *net) 181 { 182 netlink_kernel_release(net->diag_nlsk); 183 net->diag_nlsk = NULL; 184 } 185 186 static struct pernet_operations diag_net_ops = { 187 .init = diag_net_init, 188 .exit = diag_net_exit, 189 }; 190 191 static int __init sock_diag_init(void) 192 { 193 return register_pernet_subsys(&diag_net_ops); 194 } 195 196 static void __exit sock_diag_exit(void) 197 { 198 unregister_pernet_subsys(&diag_net_ops); 199 } 200 201 module_init(sock_diag_init); 202 module_exit(sock_diag_exit); 203 MODULE_LICENSE("GPL"); 204 MODULE_ALIAS_NET_PF_PROTO(PF_NETLINK, NETLINK_SOCK_DIAG); 205