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