xref: /linux/net/netlabel/netlabel_user.c (revision 32f50cdee666333168b5203c7864bede159f789e)
1 /*
2  * NetLabel NETLINK Interface
3  *
4  * This file defines the NETLINK interface for the NetLabel system.  The
5  * NetLabel system manages static and dynamic label mappings for network
6  * protocols such as CIPSO and RIPSO.
7  *
8  * Author: Paul Moore <paul.moore@hp.com>
9  *
10  */
11 
12 /*
13  * (c) Copyright Hewlett-Packard Development Company, L.P., 2006
14  *
15  * This program is free software;  you can redistribute it and/or modify
16  * it under the terms of the GNU General Public License as published by
17  * the Free Software Foundation; either version 2 of the License, or
18  * (at your option) any later version.
19  *
20  * This program is distributed in the hope that it will be useful,
21  * but WITHOUT ANY WARRANTY;  without even the implied warranty of
22  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
23  * the GNU General Public License for more details.
24  *
25  * You should have received a copy of the GNU General Public License
26  * along with this program;  if not, write to the Free Software
27  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
28  *
29  */
30 
31 #include <linux/init.h>
32 #include <linux/types.h>
33 #include <linux/list.h>
34 #include <linux/socket.h>
35 #include <linux/audit.h>
36 #include <linux/tty.h>
37 #include <linux/security.h>
38 #include <net/sock.h>
39 #include <net/netlink.h>
40 #include <net/genetlink.h>
41 #include <net/netlabel.h>
42 #include <asm/bug.h>
43 
44 #include "netlabel_mgmt.h"
45 #include "netlabel_unlabeled.h"
46 #include "netlabel_cipso_v4.h"
47 #include "netlabel_user.h"
48 
49 /*
50  * NetLabel NETLINK Setup Functions
51  */
52 
53 /**
54  * netlbl_netlink_init - Initialize the NETLINK communication channel
55  *
56  * Description:
57  * Call out to the NetLabel components so they can register their families and
58  * commands with the Generic NETLINK mechanism.  Returns zero on success and
59  * non-zero on failure.
60  *
61  */
62 int netlbl_netlink_init(void)
63 {
64 	int ret_val;
65 
66 	ret_val = netlbl_mgmt_genl_init();
67 	if (ret_val != 0)
68 		return ret_val;
69 
70 	ret_val = netlbl_cipsov4_genl_init();
71 	if (ret_val != 0)
72 		return ret_val;
73 
74 	ret_val = netlbl_unlabel_genl_init();
75 	if (ret_val != 0)
76 		return ret_val;
77 
78 	return 0;
79 }
80 
81 /*
82  * NetLabel Audit Functions
83  */
84 
85 /**
86  * netlbl_audit_start_common - Start an audit message
87  * @type: audit message type
88  * @secid: LSM context ID
89  *
90  * Description:
91  * Start an audit message using the type specified in @type and fill the audit
92  * message with some fields common to all NetLabel audit messages.  Returns
93  * a pointer to the audit buffer on success, NULL on failure.
94  *
95  */
96 struct audit_buffer *netlbl_audit_start_common(int type, u32 secid)
97 {
98 	struct audit_context *audit_ctx = current->audit_context;
99 	struct audit_buffer *audit_buf;
100 	uid_t audit_loginuid;
101 	const char *audit_tty;
102 	char audit_comm[sizeof(current->comm)];
103 	struct vm_area_struct *vma;
104 	char *secctx;
105 	u32 secctx_len;
106 
107 	audit_buf = audit_log_start(audit_ctx, GFP_ATOMIC, type);
108 	if (audit_buf == NULL)
109 		return NULL;
110 
111 	audit_loginuid = audit_get_loginuid(audit_ctx);
112 	if (current->signal &&
113 	    current->signal->tty &&
114 	    current->signal->tty->name)
115 		audit_tty = current->signal->tty->name;
116 	else
117 		audit_tty = "(none)";
118 	get_task_comm(audit_comm, current);
119 
120 	audit_log_format(audit_buf,
121 			 "netlabel: auid=%u uid=%u tty=%s pid=%d",
122 			 audit_loginuid,
123 			 current->uid,
124 			 audit_tty,
125 			 current->pid);
126 	audit_log_format(audit_buf, " comm=");
127 	audit_log_untrustedstring(audit_buf, audit_comm);
128 	if (current->mm) {
129 		down_read(&current->mm->mmap_sem);
130 		vma = current->mm->mmap;
131 		while (vma) {
132 			if ((vma->vm_flags & VM_EXECUTABLE) &&
133 			    vma->vm_file) {
134 				audit_log_d_path(audit_buf,
135 						 " exe=",
136 						 vma->vm_file->f_dentry,
137 						 vma->vm_file->f_vfsmnt);
138 				break;
139 			}
140 			vma = vma->vm_next;
141 		}
142 		up_read(&current->mm->mmap_sem);
143 	}
144 
145 	if (secid != 0 &&
146 	    security_secid_to_secctx(secid, &secctx, &secctx_len) == 0)
147 		audit_log_format(audit_buf, " subj=%s", secctx);
148 
149 	return audit_buf;
150 }
151 
152 /**
153  * netlbl_audit_nomsg - Send an audit message without additional text
154  * @type: audit message type
155  * @secid: LSM context ID
156  *
157  * Description:
158  * Send an audit message with only the common NetLabel audit fields.
159  *
160  */
161 void netlbl_audit_nomsg(int type, u32 secid)
162 {
163 	struct audit_buffer *audit_buf;
164 
165 	audit_buf = netlbl_audit_start_common(type, secid);
166 	audit_log_end(audit_buf);
167 }
168