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 int sock_diag_put_filterinfo(struct user_namespace *user_ns, struct sock *sk, 53 struct sk_buff *skb, int attrtype) 54 { 55 struct nlattr *attr; 56 struct sk_filter *filter; 57 unsigned int len; 58 int err = 0; 59 60 if (!ns_capable(user_ns, CAP_NET_ADMIN)) { 61 nla_reserve(skb, attrtype, 0); 62 return 0; 63 } 64 65 rcu_read_lock(); 66 67 filter = rcu_dereference(sk->sk_filter); 68 len = filter ? filter->len * sizeof(struct sock_filter) : 0; 69 70 attr = nla_reserve(skb, attrtype, len); 71 if (attr == NULL) { 72 err = -EMSGSIZE; 73 goto out; 74 } 75 76 if (filter) { 77 struct sock_filter *fb = (struct sock_filter *)nla_data(attr); 78 int i; 79 80 for (i = 0; i < filter->len; i++, fb++) 81 sk_decode_filter(&filter->insns[i], fb); 82 } 83 84 out: 85 rcu_read_unlock(); 86 return err; 87 } 88 EXPORT_SYMBOL(sock_diag_put_filterinfo); 89 90 void sock_diag_register_inet_compat(int (*fn)(struct sk_buff *skb, struct nlmsghdr *nlh)) 91 { 92 mutex_lock(&sock_diag_table_mutex); 93 inet_rcv_compat = fn; 94 mutex_unlock(&sock_diag_table_mutex); 95 } 96 EXPORT_SYMBOL_GPL(sock_diag_register_inet_compat); 97 98 void sock_diag_unregister_inet_compat(int (*fn)(struct sk_buff *skb, struct nlmsghdr *nlh)) 99 { 100 mutex_lock(&sock_diag_table_mutex); 101 inet_rcv_compat = NULL; 102 mutex_unlock(&sock_diag_table_mutex); 103 } 104 EXPORT_SYMBOL_GPL(sock_diag_unregister_inet_compat); 105 106 int sock_diag_register(const struct sock_diag_handler *hndl) 107 { 108 int err = 0; 109 110 if (hndl->family >= AF_MAX) 111 return -EINVAL; 112 113 mutex_lock(&sock_diag_table_mutex); 114 if (sock_diag_handlers[hndl->family]) 115 err = -EBUSY; 116 else 117 sock_diag_handlers[hndl->family] = hndl; 118 mutex_unlock(&sock_diag_table_mutex); 119 120 return err; 121 } 122 EXPORT_SYMBOL_GPL(sock_diag_register); 123 124 void sock_diag_unregister(const struct sock_diag_handler *hnld) 125 { 126 int family = hnld->family; 127 128 if (family >= AF_MAX) 129 return; 130 131 mutex_lock(&sock_diag_table_mutex); 132 BUG_ON(sock_diag_handlers[family] != hnld); 133 sock_diag_handlers[family] = NULL; 134 mutex_unlock(&sock_diag_table_mutex); 135 } 136 EXPORT_SYMBOL_GPL(sock_diag_unregister); 137 138 static int __sock_diag_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh) 139 { 140 int err; 141 struct sock_diag_req *req = nlmsg_data(nlh); 142 const struct sock_diag_handler *hndl; 143 144 if (nlmsg_len(nlh) < sizeof(*req)) 145 return -EINVAL; 146 147 if (req->sdiag_family >= AF_MAX) 148 return -EINVAL; 149 150 if (sock_diag_handlers[req->sdiag_family] == NULL) 151 request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK, 152 NETLINK_SOCK_DIAG, req->sdiag_family); 153 154 mutex_lock(&sock_diag_table_mutex); 155 hndl = sock_diag_handlers[req->sdiag_family]; 156 if (hndl == NULL) 157 err = -ENOENT; 158 else 159 err = hndl->dump(skb, nlh); 160 mutex_unlock(&sock_diag_table_mutex); 161 162 return err; 163 } 164 165 static int sock_diag_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh) 166 { 167 int ret; 168 169 switch (nlh->nlmsg_type) { 170 case TCPDIAG_GETSOCK: 171 case DCCPDIAG_GETSOCK: 172 if (inet_rcv_compat == NULL) 173 request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK, 174 NETLINK_SOCK_DIAG, AF_INET); 175 176 mutex_lock(&sock_diag_table_mutex); 177 if (inet_rcv_compat != NULL) 178 ret = inet_rcv_compat(skb, nlh); 179 else 180 ret = -EOPNOTSUPP; 181 mutex_unlock(&sock_diag_table_mutex); 182 183 return ret; 184 case SOCK_DIAG_BY_FAMILY: 185 return __sock_diag_rcv_msg(skb, nlh); 186 default: 187 return -EINVAL; 188 } 189 } 190 191 static DEFINE_MUTEX(sock_diag_mutex); 192 193 static void sock_diag_rcv(struct sk_buff *skb) 194 { 195 mutex_lock(&sock_diag_mutex); 196 netlink_rcv_skb(skb, &sock_diag_rcv_msg); 197 mutex_unlock(&sock_diag_mutex); 198 } 199 200 static int __net_init diag_net_init(struct net *net) 201 { 202 struct netlink_kernel_cfg cfg = { 203 .input = sock_diag_rcv, 204 }; 205 206 net->diag_nlsk = netlink_kernel_create(net, NETLINK_SOCK_DIAG, &cfg); 207 return net->diag_nlsk == NULL ? -ENOMEM : 0; 208 } 209 210 static void __net_exit diag_net_exit(struct net *net) 211 { 212 netlink_kernel_release(net->diag_nlsk); 213 net->diag_nlsk = NULL; 214 } 215 216 static struct pernet_operations diag_net_ops = { 217 .init = diag_net_init, 218 .exit = diag_net_exit, 219 }; 220 221 static int __init sock_diag_init(void) 222 { 223 return register_pernet_subsys(&diag_net_ops); 224 } 225 226 static void __exit sock_diag_exit(void) 227 { 228 unregister_pernet_subsys(&diag_net_ops); 229 } 230 231 module_init(sock_diag_init); 232 module_exit(sock_diag_exit); 233 MODULE_LICENSE("GPL"); 234 MODULE_ALIAS_NET_PF_PROTO(PF_NETLINK, NETLINK_SOCK_DIAG); 235