net: phy: micrel: Move netif_rx() outside of IRQ-off section.
[linux-2.6-microblaze.git] / security / lsm_audit.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * common LSM auditing functions
4  *
5  * Based on code written for SELinux by :
6  *                      Stephen Smalley, <sds@tycho.nsa.gov>
7  *                      James Morris <jmorris@redhat.com>
8  * Author : Etienne Basset, <etienne.basset@ensta.org>
9  */
10
11 #include <linux/types.h>
12 #include <linux/stddef.h>
13 #include <linux/kernel.h>
14 #include <linux/gfp.h>
15 #include <linux/fs.h>
16 #include <linux/init.h>
17 #include <net/sock.h>
18 #include <linux/un.h>
19 #include <net/af_unix.h>
20 #include <linux/audit.h>
21 #include <linux/ipv6.h>
22 #include <linux/ip.h>
23 #include <net/ip.h>
24 #include <net/ipv6.h>
25 #include <linux/tcp.h>
26 #include <linux/udp.h>
27 #include <linux/dccp.h>
28 #include <linux/sctp.h>
29 #include <linux/lsm_audit.h>
30 #include <linux/security.h>
31
32 /**
33  * ipv4_skb_to_auditdata : fill auditdata from skb
34  * @skb : the skb
35  * @ad : the audit data to fill
36  * @proto : the layer 4 protocol
37  *
38  * return  0 on success
39  */
40 int ipv4_skb_to_auditdata(struct sk_buff *skb,
41                 struct common_audit_data *ad, u8 *proto)
42 {
43         int ret = 0;
44         struct iphdr *ih;
45
46         ih = ip_hdr(skb);
47         if (ih == NULL)
48                 return -EINVAL;
49
50         ad->u.net->v4info.saddr = ih->saddr;
51         ad->u.net->v4info.daddr = ih->daddr;
52
53         if (proto)
54                 *proto = ih->protocol;
55         /* non initial fragment */
56         if (ntohs(ih->frag_off) & IP_OFFSET)
57                 return 0;
58
59         switch (ih->protocol) {
60         case IPPROTO_TCP: {
61                 struct tcphdr *th = tcp_hdr(skb);
62                 if (th == NULL)
63                         break;
64
65                 ad->u.net->sport = th->source;
66                 ad->u.net->dport = th->dest;
67                 break;
68         }
69         case IPPROTO_UDP: {
70                 struct udphdr *uh = udp_hdr(skb);
71                 if (uh == NULL)
72                         break;
73
74                 ad->u.net->sport = uh->source;
75                 ad->u.net->dport = uh->dest;
76                 break;
77         }
78         case IPPROTO_DCCP: {
79                 struct dccp_hdr *dh = dccp_hdr(skb);
80                 if (dh == NULL)
81                         break;
82
83                 ad->u.net->sport = dh->dccph_sport;
84                 ad->u.net->dport = dh->dccph_dport;
85                 break;
86         }
87         case IPPROTO_SCTP: {
88                 struct sctphdr *sh = sctp_hdr(skb);
89                 if (sh == NULL)
90                         break;
91                 ad->u.net->sport = sh->source;
92                 ad->u.net->dport = sh->dest;
93                 break;
94         }
95         default:
96                 ret = -EINVAL;
97         }
98         return ret;
99 }
100 #if IS_ENABLED(CONFIG_IPV6)
101 /**
102  * ipv6_skb_to_auditdata : fill auditdata from skb
103  * @skb : the skb
104  * @ad : the audit data to fill
105  * @proto : the layer 4 protocol
106  *
107  * return  0 on success
108  */
109 int ipv6_skb_to_auditdata(struct sk_buff *skb,
110                 struct common_audit_data *ad, u8 *proto)
111 {
112         int offset, ret = 0;
113         struct ipv6hdr *ip6;
114         u8 nexthdr;
115         __be16 frag_off;
116
117         ip6 = ipv6_hdr(skb);
118         if (ip6 == NULL)
119                 return -EINVAL;
120         ad->u.net->v6info.saddr = ip6->saddr;
121         ad->u.net->v6info.daddr = ip6->daddr;
122         /* IPv6 can have several extension header before the Transport header
123          * skip them */
124         offset = skb_network_offset(skb);
125         offset += sizeof(*ip6);
126         nexthdr = ip6->nexthdr;
127         offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
128         if (offset < 0)
129                 return 0;
130         if (proto)
131                 *proto = nexthdr;
132         switch (nexthdr) {
133         case IPPROTO_TCP: {
134                 struct tcphdr _tcph, *th;
135
136                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
137                 if (th == NULL)
138                         break;
139
140                 ad->u.net->sport = th->source;
141                 ad->u.net->dport = th->dest;
142                 break;
143         }
144         case IPPROTO_UDP: {
145                 struct udphdr _udph, *uh;
146
147                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
148                 if (uh == NULL)
149                         break;
150
151                 ad->u.net->sport = uh->source;
152                 ad->u.net->dport = uh->dest;
153                 break;
154         }
155         case IPPROTO_DCCP: {
156                 struct dccp_hdr _dccph, *dh;
157
158                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
159                 if (dh == NULL)
160                         break;
161
162                 ad->u.net->sport = dh->dccph_sport;
163                 ad->u.net->dport = dh->dccph_dport;
164                 break;
165         }
166         case IPPROTO_SCTP: {
167                 struct sctphdr _sctph, *sh;
168
169                 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
170                 if (sh == NULL)
171                         break;
172                 ad->u.net->sport = sh->source;
173                 ad->u.net->dport = sh->dest;
174                 break;
175         }
176         default:
177                 ret = -EINVAL;
178         }
179         return ret;
180 }
181 #endif
182
183
184 static inline void print_ipv6_addr(struct audit_buffer *ab,
185                                    const struct in6_addr *addr, __be16 port,
186                                    char *name1, char *name2)
187 {
188         if (!ipv6_addr_any(addr))
189                 audit_log_format(ab, " %s=%pI6c", name1, addr);
190         if (port)
191                 audit_log_format(ab, " %s=%d", name2, ntohs(port));
192 }
193
194 static inline void print_ipv4_addr(struct audit_buffer *ab, __be32 addr,
195                                    __be16 port, char *name1, char *name2)
196 {
197         if (addr)
198                 audit_log_format(ab, " %s=%pI4", name1, &addr);
199         if (port)
200                 audit_log_format(ab, " %s=%d", name2, ntohs(port));
201 }
202
203 /**
204  * dump_common_audit_data - helper to dump common audit data
205  * @a : common audit data
206  *
207  */
208 static void dump_common_audit_data(struct audit_buffer *ab,
209                                    struct common_audit_data *a)
210 {
211         char comm[sizeof(current->comm)];
212
213         /*
214          * To keep stack sizes in check force programers to notice if they
215          * start making this union too large!  See struct lsm_network_audit
216          * as an example of how to deal with large data.
217          */
218         BUILD_BUG_ON(sizeof(a->u) > sizeof(void *)*2);
219
220         audit_log_format(ab, " pid=%d comm=", task_tgid_nr(current));
221         audit_log_untrustedstring(ab, memcpy(comm, current->comm, sizeof(comm)));
222
223         switch (a->type) {
224         case LSM_AUDIT_DATA_NONE:
225                 return;
226         case LSM_AUDIT_DATA_IPC:
227                 audit_log_format(ab, " ipc_key=%d ", a->u.ipc_id);
228                 break;
229         case LSM_AUDIT_DATA_CAP:
230                 audit_log_format(ab, " capability=%d ", a->u.cap);
231                 break;
232         case LSM_AUDIT_DATA_PATH: {
233                 struct inode *inode;
234
235                 audit_log_d_path(ab, " path=", &a->u.path);
236
237                 inode = d_backing_inode(a->u.path.dentry);
238                 if (inode) {
239                         audit_log_format(ab, " dev=");
240                         audit_log_untrustedstring(ab, inode->i_sb->s_id);
241                         audit_log_format(ab, " ino=%lu", inode->i_ino);
242                 }
243                 break;
244         }
245         case LSM_AUDIT_DATA_FILE: {
246                 struct inode *inode;
247
248                 audit_log_d_path(ab, " path=", &a->u.file->f_path);
249
250                 inode = file_inode(a->u.file);
251                 if (inode) {
252                         audit_log_format(ab, " dev=");
253                         audit_log_untrustedstring(ab, inode->i_sb->s_id);
254                         audit_log_format(ab, " ino=%lu", inode->i_ino);
255                 }
256                 break;
257         }
258         case LSM_AUDIT_DATA_IOCTL_OP: {
259                 struct inode *inode;
260
261                 audit_log_d_path(ab, " path=", &a->u.op->path);
262
263                 inode = a->u.op->path.dentry->d_inode;
264                 if (inode) {
265                         audit_log_format(ab, " dev=");
266                         audit_log_untrustedstring(ab, inode->i_sb->s_id);
267                         audit_log_format(ab, " ino=%lu", inode->i_ino);
268                 }
269
270                 audit_log_format(ab, " ioctlcmd=0x%hx", a->u.op->cmd);
271                 break;
272         }
273         case LSM_AUDIT_DATA_DENTRY: {
274                 struct inode *inode;
275
276                 audit_log_format(ab, " name=");
277                 spin_lock(&a->u.dentry->d_lock);
278                 audit_log_untrustedstring(ab, a->u.dentry->d_name.name);
279                 spin_unlock(&a->u.dentry->d_lock);
280
281                 inode = d_backing_inode(a->u.dentry);
282                 if (inode) {
283                         audit_log_format(ab, " dev=");
284                         audit_log_untrustedstring(ab, inode->i_sb->s_id);
285                         audit_log_format(ab, " ino=%lu", inode->i_ino);
286                 }
287                 break;
288         }
289         case LSM_AUDIT_DATA_INODE: {
290                 struct dentry *dentry;
291                 struct inode *inode;
292
293                 rcu_read_lock();
294                 inode = a->u.inode;
295                 dentry = d_find_alias_rcu(inode);
296                 if (dentry) {
297                         audit_log_format(ab, " name=");
298                         spin_lock(&dentry->d_lock);
299                         audit_log_untrustedstring(ab, dentry->d_name.name);
300                         spin_unlock(&dentry->d_lock);
301                 }
302                 audit_log_format(ab, " dev=");
303                 audit_log_untrustedstring(ab, inode->i_sb->s_id);
304                 audit_log_format(ab, " ino=%lu", inode->i_ino);
305                 rcu_read_unlock();
306                 break;
307         }
308         case LSM_AUDIT_DATA_TASK: {
309                 struct task_struct *tsk = a->u.tsk;
310                 if (tsk) {
311                         pid_t pid = task_tgid_nr(tsk);
312                         if (pid) {
313                                 char comm[sizeof(tsk->comm)];
314                                 audit_log_format(ab, " opid=%d ocomm=", pid);
315                                 audit_log_untrustedstring(ab,
316                                     memcpy(comm, tsk->comm, sizeof(comm)));
317                         }
318                 }
319                 break;
320         }
321         case LSM_AUDIT_DATA_NET:
322                 if (a->u.net->sk) {
323                         const struct sock *sk = a->u.net->sk;
324                         struct unix_sock *u;
325                         struct unix_address *addr;
326                         int len = 0;
327                         char *p = NULL;
328
329                         switch (sk->sk_family) {
330                         case AF_INET: {
331                                 struct inet_sock *inet = inet_sk(sk);
332
333                                 print_ipv4_addr(ab, inet->inet_rcv_saddr,
334                                                 inet->inet_sport,
335                                                 "laddr", "lport");
336                                 print_ipv4_addr(ab, inet->inet_daddr,
337                                                 inet->inet_dport,
338                                                 "faddr", "fport");
339                                 break;
340                         }
341 #if IS_ENABLED(CONFIG_IPV6)
342                         case AF_INET6: {
343                                 struct inet_sock *inet = inet_sk(sk);
344
345                                 print_ipv6_addr(ab, &sk->sk_v6_rcv_saddr,
346                                                 inet->inet_sport,
347                                                 "laddr", "lport");
348                                 print_ipv6_addr(ab, &sk->sk_v6_daddr,
349                                                 inet->inet_dport,
350                                                 "faddr", "fport");
351                                 break;
352                         }
353 #endif
354                         case AF_UNIX:
355                                 u = unix_sk(sk);
356                                 addr = smp_load_acquire(&u->addr);
357                                 if (!addr)
358                                         break;
359                                 if (u->path.dentry) {
360                                         audit_log_d_path(ab, " path=", &u->path);
361                                         break;
362                                 }
363                                 len = addr->len-sizeof(short);
364                                 p = &addr->name->sun_path[0];
365                                 audit_log_format(ab, " path=");
366                                 if (*p)
367                                         audit_log_untrustedstring(ab, p);
368                                 else
369                                         audit_log_n_hex(ab, p, len);
370                                 break;
371                         }
372                 }
373
374                 switch (a->u.net->family) {
375                 case AF_INET:
376                         print_ipv4_addr(ab, a->u.net->v4info.saddr,
377                                         a->u.net->sport,
378                                         "saddr", "src");
379                         print_ipv4_addr(ab, a->u.net->v4info.daddr,
380                                         a->u.net->dport,
381                                         "daddr", "dest");
382                         break;
383                 case AF_INET6:
384                         print_ipv6_addr(ab, &a->u.net->v6info.saddr,
385                                         a->u.net->sport,
386                                         "saddr", "src");
387                         print_ipv6_addr(ab, &a->u.net->v6info.daddr,
388                                         a->u.net->dport,
389                                         "daddr", "dest");
390                         break;
391                 }
392                 if (a->u.net->netif > 0) {
393                         struct net_device *dev;
394
395                         /* NOTE: we always use init's namespace */
396                         dev = dev_get_by_index(&init_net, a->u.net->netif);
397                         if (dev) {
398                                 audit_log_format(ab, " netif=%s", dev->name);
399                                 dev_put(dev);
400                         }
401                 }
402                 break;
403 #ifdef CONFIG_KEYS
404         case LSM_AUDIT_DATA_KEY:
405                 audit_log_format(ab, " key_serial=%u", a->u.key_struct.key);
406                 if (a->u.key_struct.key_desc) {
407                         audit_log_format(ab, " key_desc=");
408                         audit_log_untrustedstring(ab, a->u.key_struct.key_desc);
409                 }
410                 break;
411 #endif
412         case LSM_AUDIT_DATA_KMOD:
413                 audit_log_format(ab, " kmod=");
414                 audit_log_untrustedstring(ab, a->u.kmod_name);
415                 break;
416         case LSM_AUDIT_DATA_IBPKEY: {
417                 struct in6_addr sbn_pfx;
418
419                 memset(&sbn_pfx.s6_addr, 0,
420                        sizeof(sbn_pfx.s6_addr));
421                 memcpy(&sbn_pfx.s6_addr, &a->u.ibpkey->subnet_prefix,
422                        sizeof(a->u.ibpkey->subnet_prefix));
423                 audit_log_format(ab, " pkey=0x%x subnet_prefix=%pI6c",
424                                  a->u.ibpkey->pkey, &sbn_pfx);
425                 break;
426         }
427         case LSM_AUDIT_DATA_IBENDPORT:
428                 audit_log_format(ab, " device=%s port_num=%u",
429                                  a->u.ibendport->dev_name,
430                                  a->u.ibendport->port);
431                 break;
432         case LSM_AUDIT_DATA_LOCKDOWN:
433                 audit_log_format(ab, " lockdown_reason=\"%s\"",
434                                  lockdown_reasons[a->u.reason]);
435                 break;
436         } /* switch (a->type) */
437 }
438
439 /**
440  * common_lsm_audit - generic LSM auditing function
441  * @a:  auxiliary audit data
442  * @pre_audit: lsm-specific pre-audit callback
443  * @post_audit: lsm-specific post-audit callback
444  *
445  * setup the audit buffer for common security information
446  * uses callback to print LSM specific information
447  */
448 void common_lsm_audit(struct common_audit_data *a,
449         void (*pre_audit)(struct audit_buffer *, void *),
450         void (*post_audit)(struct audit_buffer *, void *))
451 {
452         struct audit_buffer *ab;
453
454         if (a == NULL)
455                 return;
456         /* we use GFP_ATOMIC so we won't sleep */
457         ab = audit_log_start(audit_context(), GFP_ATOMIC | __GFP_NOWARN,
458                              AUDIT_AVC);
459
460         if (ab == NULL)
461                 return;
462
463         if (pre_audit)
464                 pre_audit(ab, a);
465
466         dump_common_audit_data(ab, a);
467
468         if (post_audit)
469                 post_audit(ab, a);
470
471         audit_log_end(ab);
472 }