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 static u64 sock_gen_cookie(struct sock *sk) 17 { 18 while (1) { 19 u64 res = atomic64_read(&sk->sk_cookie); 20 21 if (res) 22 return res; 23 res = atomic64_inc_return(&sock_net(sk)->cookie_gen); 24 atomic64_cmpxchg(&sk->sk_cookie, 0, res); 25 } 26 } 27 28 int sock_diag_check_cookie(struct sock *sk, const __u32 *cookie) 29 { 30 u64 res; 31 32 if (cookie[0] == INET_DIAG_NOCOOKIE && cookie[1] == INET_DIAG_NOCOOKIE) 33 return 0; 34 35 res = sock_gen_cookie(sk); 36 if ((u32)res != cookie[0] || (u32)(res >> 32) != cookie[1]) 37 return -ESTALE; 38 39 return 0; 40 } 41 EXPORT_SYMBOL_GPL(sock_diag_check_cookie); 42 43 void sock_diag_save_cookie(struct sock *sk, __u32 *cookie) 44 { 45 u64 res = sock_gen_cookie(sk); 46 47 cookie[0] = (u32)res; 48 cookie[1] = (u32)(res >> 32); 49 } 50 EXPORT_SYMBOL_GPL(sock_diag_save_cookie); 51 52 int sock_diag_put_meminfo(struct sock *sk, struct sk_buff *skb, int attrtype) 53 { 54 u32 mem[SK_MEMINFO_VARS]; 55 56 mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk); 57 mem[SK_MEMINFO_RCVBUF] = sk->sk_rcvbuf; 58 mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk); 59 mem[SK_MEMINFO_SNDBUF] = sk->sk_sndbuf; 60 mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc; 61 mem[SK_MEMINFO_WMEM_QUEUED] = sk->sk_wmem_queued; 62 mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc); 63 mem[SK_MEMINFO_BACKLOG] = sk->sk_backlog.len; 64 65 return nla_put(skb, attrtype, sizeof(mem), &mem); 66 } 67 EXPORT_SYMBOL_GPL(sock_diag_put_meminfo); 68 69 int sock_diag_put_filterinfo(bool may_report_filterinfo, struct sock *sk, 70 struct sk_buff *skb, int attrtype) 71 { 72 struct sock_fprog_kern *fprog; 73 struct sk_filter *filter; 74 struct nlattr *attr; 75 unsigned int flen; 76 int err = 0; 77 78 if (!may_report_filterinfo) { 79 nla_reserve(skb, attrtype, 0); 80 return 0; 81 } 82 83 rcu_read_lock(); 84 filter = rcu_dereference(sk->sk_filter); 85 if (!filter) 86 goto out; 87 88 fprog = filter->prog->orig_prog; 89 flen = bpf_classic_proglen(fprog); 90 91 attr = nla_reserve(skb, attrtype, flen); 92 if (attr == NULL) { 93 err = -EMSGSIZE; 94 goto out; 95 } 96 97 memcpy(nla_data(attr), fprog->filter, flen); 98 out: 99 rcu_read_unlock(); 100 return err; 101 } 102 EXPORT_SYMBOL(sock_diag_put_filterinfo); 103 104 void sock_diag_register_inet_compat(int (*fn)(struct sk_buff *skb, struct nlmsghdr *nlh)) 105 { 106 mutex_lock(&sock_diag_table_mutex); 107 inet_rcv_compat = fn; 108 mutex_unlock(&sock_diag_table_mutex); 109 } 110 EXPORT_SYMBOL_GPL(sock_diag_register_inet_compat); 111 112 void sock_diag_unregister_inet_compat(int (*fn)(struct sk_buff *skb, struct nlmsghdr *nlh)) 113 { 114 mutex_lock(&sock_diag_table_mutex); 115 inet_rcv_compat = NULL; 116 mutex_unlock(&sock_diag_table_mutex); 117 } 118 EXPORT_SYMBOL_GPL(sock_diag_unregister_inet_compat); 119 120 int sock_diag_register(const struct sock_diag_handler *hndl) 121 { 122 int err = 0; 123 124 if (hndl->family >= AF_MAX) 125 return -EINVAL; 126 127 mutex_lock(&sock_diag_table_mutex); 128 if (sock_diag_handlers[hndl->family]) 129 err = -EBUSY; 130 else 131 sock_diag_handlers[hndl->family] = hndl; 132 mutex_unlock(&sock_diag_table_mutex); 133 134 return err; 135 } 136 EXPORT_SYMBOL_GPL(sock_diag_register); 137 138 void sock_diag_unregister(const struct sock_diag_handler *hnld) 139 { 140 int family = hnld->family; 141 142 if (family >= AF_MAX) 143 return; 144 145 mutex_lock(&sock_diag_table_mutex); 146 BUG_ON(sock_diag_handlers[family] != hnld); 147 sock_diag_handlers[family] = NULL; 148 mutex_unlock(&sock_diag_table_mutex); 149 } 150 EXPORT_SYMBOL_GPL(sock_diag_unregister); 151 152 static int __sock_diag_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh) 153 { 154 int err; 155 struct sock_diag_req *req = nlmsg_data(nlh); 156 const struct sock_diag_handler *hndl; 157 158 if (nlmsg_len(nlh) < sizeof(*req)) 159 return -EINVAL; 160 161 if (req->sdiag_family >= AF_MAX) 162 return -EINVAL; 163 164 if (sock_diag_handlers[req->sdiag_family] == NULL) 165 request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK, 166 NETLINK_SOCK_DIAG, req->sdiag_family); 167 168 mutex_lock(&sock_diag_table_mutex); 169 hndl = sock_diag_handlers[req->sdiag_family]; 170 if (hndl == NULL) 171 err = -ENOENT; 172 else 173 err = hndl->dump(skb, nlh); 174 mutex_unlock(&sock_diag_table_mutex); 175 176 return err; 177 } 178 179 static int sock_diag_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh) 180 { 181 int ret; 182 183 switch (nlh->nlmsg_type) { 184 case TCPDIAG_GETSOCK: 185 case DCCPDIAG_GETSOCK: 186 if (inet_rcv_compat == NULL) 187 request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK, 188 NETLINK_SOCK_DIAG, AF_INET); 189 190 mutex_lock(&sock_diag_table_mutex); 191 if (inet_rcv_compat != NULL) 192 ret = inet_rcv_compat(skb, nlh); 193 else 194 ret = -EOPNOTSUPP; 195 mutex_unlock(&sock_diag_table_mutex); 196 197 return ret; 198 case SOCK_DIAG_BY_FAMILY: 199 return __sock_diag_rcv_msg(skb, nlh); 200 default: 201 return -EINVAL; 202 } 203 } 204 205 static DEFINE_MUTEX(sock_diag_mutex); 206 207 static void sock_diag_rcv(struct sk_buff *skb) 208 { 209 mutex_lock(&sock_diag_mutex); 210 netlink_rcv_skb(skb, &sock_diag_rcv_msg); 211 mutex_unlock(&sock_diag_mutex); 212 } 213 214 static int __net_init diag_net_init(struct net *net) 215 { 216 struct netlink_kernel_cfg cfg = { 217 .input = sock_diag_rcv, 218 }; 219 220 net->diag_nlsk = netlink_kernel_create(net, NETLINK_SOCK_DIAG, &cfg); 221 return net->diag_nlsk == NULL ? -ENOMEM : 0; 222 } 223 224 static void __net_exit diag_net_exit(struct net *net) 225 { 226 netlink_kernel_release(net->diag_nlsk); 227 net->diag_nlsk = NULL; 228 } 229 230 static struct pernet_operations diag_net_ops = { 231 .init = diag_net_init, 232 .exit = diag_net_exit, 233 }; 234 235 static int __init sock_diag_init(void) 236 { 237 return register_pernet_subsys(&diag_net_ops); 238 } 239 240 static void __exit sock_diag_exit(void) 241 { 242 unregister_pernet_subsys(&diag_net_ops); 243 } 244 245 module_init(sock_diag_init); 246 module_exit(sock_diag_exit); 247 MODULE_LICENSE("GPL"); 248 MODULE_ALIAS_NET_PF_PROTO(PF_NETLINK, NETLINK_SOCK_DIAG); 249