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