[NetLabel]: add audit support for configuration changes

This patch adds audit support to NetLabel, including six new audit message
types shown below.

 #define AUDIT_MAC_UNLBL_ACCEPT 1406
 #define AUDIT_MAC_UNLBL_DENY   1407
 #define AUDIT_MAC_CIPSOV4_ADD  1408
 #define AUDIT_MAC_CIPSOV4_DEL  1409
 #define AUDIT_MAC_MAP_ADD      1410
 #define AUDIT_MAC_MAP_DEL      1411

Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

8 files changed, 224 insertions, 34 deletions

diff --git a/net/ipv4/cipso_ipv4.c b/net/ipv4/cipso_ipv4.c
index e6ce0b3ba62a..c4e469ff842d 100644
--- a/net/ipv4/cipso_ipv4.c
+++ b/net/ipv4/cipso_ipv4.c
@@ -474,6 +474,7 @@ doi_add_failure_rlock:
 /**
  * cipso_v4_doi_remove - Remove an existing DOI from the CIPSO protocol engine
  * @doi: the DOI value
+ * @audit_secid: the LSM secid to use in the audit message
  * @callback: the DOI cleanup/free callback
  *
  * Description:
@@ -483,7 +484,9 @@ doi_add_failure_rlock:
  * success and negative values on failure.
  *
  */
-int cipso_v4_doi_remove(u32 doi, void (*callback) (struct rcu_head * head))
+int cipso_v4_doi_remove(u32 doi,
+                        u32 audit_secid,
+                        void (*callback) (struct rcu_head * head))
 {
         struct cipso_v4_doi *doi_def;
         struct cipso_v4_domhsh_entry *dom_iter;
@@ -502,7 +505,8 @@ int cipso_v4_doi_remove(u32 doi, void (*callback) (struct rcu_head * head))
                 spin_unlock(&cipso_v4_doi_list_lock);
                 list_for_each_entry_rcu(dom_iter, &doi_def->dom_list, list)
                         if (dom_iter->valid)
-                                netlbl_domhsh_remove(dom_iter->domain);
+                                netlbl_domhsh_remove(dom_iter->domain,
+                                                     audit_secid);
                 cipso_v4_cache_invalidate();
                 rcu_read_unlock();
 
diff --git a/net/netlabel/netlabel_cipso_v4.c b/net/netlabel/netlabel_cipso_v4.c
index 4125a55f469f..09986ca962a6 100644
--- a/net/netlabel/netlabel_cipso_v4.c
+++ b/net/netlabel/netlabel_cipso_v4.c
@@ -32,6 +32,7 @@
 #include <linux/socket.h>
 #include <linux/string.h>
 #include <linux/skbuff.h>
+#include <linux/audit.h>
 #include <net/sock.h>
 #include <net/netlink.h>
 #include <net/genetlink.h>
@@ -162,8 +163,7 @@ static int netlbl_cipsov4_add_std(struct genl_info *info)
         int nla_a_rem;
         int nla_b_rem;
 
-        if (!info->attrs[NLBL_CIPSOV4_A_DOI] ||
-            !info->attrs[NLBL_CIPSOV4_A_TAGLST] ||
+        if (!info->attrs[NLBL_CIPSOV4_A_TAGLST] ||
             !info->attrs[NLBL_CIPSOV4_A_MLSLVLLST])
                 return -EINVAL;
 
@@ -344,8 +344,7 @@ static int netlbl_cipsov4_add_pass(struct genl_info *info)
         int ret_val;
         struct cipso_v4_doi *doi_def = NULL;
 
-        if (!info->attrs[NLBL_CIPSOV4_A_DOI] ||
-            !info->attrs[NLBL_CIPSOV4_A_TAGLST])
+        if (!info->attrs[NLBL_CIPSOV4_A_TAGLST])
                 return -EINVAL;
 
         doi_def = kmalloc(sizeof(*doi_def), GFP_KERNEL);
@@ -381,21 +380,35 @@ static int netlbl_cipsov4_add(struct sk_buff *skb, struct genl_info *info)
 
 {
         int ret_val = -EINVAL;
-        u32 map_type;
+        u32 type;
+        u32 doi;
+        const char *type_str = "(unknown)";
+        struct audit_buffer *audit_buf;
 
-        if (!info->attrs[NLBL_CIPSOV4_A_MTYPE])
+        if (!info->attrs[NLBL_CIPSOV4_A_DOI] ||
+            !info->attrs[NLBL_CIPSOV4_A_MTYPE])
                 return -EINVAL;
 
-        map_type = nla_get_u32(info->attrs[NLBL_CIPSOV4_A_MTYPE]);
-        switch (map_type) {
+        type = nla_get_u32(info->attrs[NLBL_CIPSOV4_A_MTYPE]);
+        switch (type) {
         case CIPSO_V4_MAP_STD:
+                type_str = "std";
                 ret_val = netlbl_cipsov4_add_std(info);
                 break;
         case CIPSO_V4_MAP_PASS:
+                type_str = "pass";
                 ret_val = netlbl_cipsov4_add_pass(info);
                 break;
         }
 
+        if (ret_val == 0) {
+                doi = nla_get_u32(info->attrs[NLBL_CIPSOV4_A_DOI]);
+                audit_buf = netlbl_audit_start_common(AUDIT_MAC_CIPSOV4_ADD,
+                                                      NETLINK_CB(skb).sid);
+                audit_log_format(audit_buf, " doi=%u type=%s", doi, type_str);
+                audit_log_end(audit_buf);
+        }
+
         return ret_val;
 }
 
@@ -653,11 +666,21 @@ static int netlbl_cipsov4_listall(struct sk_buff *skb,
 static int netlbl_cipsov4_remove(struct sk_buff *skb, struct genl_info *info)
 {
         int ret_val = -EINVAL;
-        u32 doi;
+        u32 doi = 0;
+        struct audit_buffer *audit_buf;
 
         if (info->attrs[NLBL_CIPSOV4_A_DOI]) {
                 doi = nla_get_u32(info->attrs[NLBL_CIPSOV4_A_DOI]);
-                ret_val = cipso_v4_doi_remove(doi, netlbl_cipsov4_doi_free);
+                ret_val = cipso_v4_doi_remove(doi,
+                                              NETLINK_CB(skb).sid,
+                                              netlbl_cipsov4_doi_free);
+        }
+
+        if (ret_val == 0) {
+                audit_buf = netlbl_audit_start_common(AUDIT_MAC_CIPSOV4_DEL,
+                                                      NETLINK_CB(skb).sid);
+                audit_log_format(audit_buf, " doi=%u", doi);
+                audit_log_end(audit_buf);
         }
 
         return ret_val;
diff --git a/net/netlabel/netlabel_domainhash.c b/net/netlabel/netlabel_domainhash.c
index f56d7a8ac7b7..d64e2ae3b129 100644
--- a/net/netlabel/netlabel_domainhash.c
+++ b/net/netlabel/netlabel_domainhash.c
@@ -35,12 +35,14 @@
 #include <linux/skbuff.h>
 #include <linux/spinlock.h>
 #include <linux/string.h>
+#include <linux/audit.h>
 #include <net/netlabel.h>
 #include <net/cipso_ipv4.h>
 #include <asm/bug.h>
 
 #include "netlabel_mgmt.h"
 #include "netlabel_domainhash.h"
+#include "netlabel_user.h"
 
 struct netlbl_domhsh_tbl {
         struct list_head *tbl;
@@ -186,6 +188,7 @@ int netlbl_domhsh_init(u32 size)
 /**
  * netlbl_domhsh_add - Adds a entry to the domain hash table
  * @entry: the entry to add
+ * @audit_secid: the LSM secid to use in the audit message
  *
  * Description:
  * Adds a new entry to the domain hash table and handles any updates to the
@@ -193,10 +196,12 @@ int netlbl_domhsh_init(u32 size)
  * negative on failure.
  *
  */
-int netlbl_domhsh_add(struct netlbl_dom_map *entry)
+int netlbl_domhsh_add(struct netlbl_dom_map *entry, u32 audit_secid)
 {
         int ret_val;
         u32 bkt;
+        struct audit_buffer *audit_buf;
+        char *audit_domain;
 
         switch (entry->type) {
         case NETLBL_NLTYPE_UNLABELED:
@@ -236,6 +241,26 @@ int netlbl_domhsh_add(struct netlbl_dom_map *entry)
                 spin_unlock(&netlbl_domhsh_def_lock);
         } else
                 ret_val = -EINVAL;
+        if (ret_val == 0) {
+                if (entry->domain != NULL)
+                        audit_domain = entry->domain;
+                else
+                        audit_domain = "(default)";
+                audit_buf = netlbl_audit_start_common(AUDIT_MAC_MAP_ADD,
+                                                      audit_secid);
+                audit_log_format(audit_buf, " domain=%s", audit_domain);
+                switch (entry->type) {
+                case NETLBL_NLTYPE_UNLABELED:
+                        audit_log_format(audit_buf, " protocol=unlbl");
+                        break;
+                case NETLBL_NLTYPE_CIPSOV4:
+                        audit_log_format(audit_buf,
+                                         " protocol=cipsov4 doi=%u",
+                                         entry->type_def.cipsov4->doi);
+                        break;
+                }
+                audit_log_end(audit_buf);
+        }
         rcu_read_unlock();
 
         if (ret_val != 0) {
@@ -254,6 +279,7 @@ int netlbl_domhsh_add(struct netlbl_dom_map *entry)
 /**
  * netlbl_domhsh_add_default - Adds the default entry to the domain hash table
  * @entry: the entry to add
+ * @audit_secid: the LSM secid to use in the audit message
  *
  * Description:
  * Adds a new default entry to the domain hash table and handles any updates
@@ -261,14 +287,15 @@ int netlbl_domhsh_add(struct netlbl_dom_map *entry)
  * negative on failure.
  *
  */
-int netlbl_domhsh_add_default(struct netlbl_dom_map *entry)
+int netlbl_domhsh_add_default(struct netlbl_dom_map *entry, u32 audit_secid)
 {
-        return netlbl_domhsh_add(entry);
+        return netlbl_domhsh_add(entry, audit_secid);
 }
 
 /**
  * netlbl_domhsh_remove - Removes an entry from the domain hash table
  * @domain: the domain to remove
+ * @audit_secid: the LSM secid to use in the audit message
  *
  * Description:
  * Removes an entry from the domain hash table and handles any updates to the
@@ -276,10 +303,12 @@ int netlbl_domhsh_add_default(struct netlbl_dom_map *entry)
  * negative on failure.
  *
  */
-int netlbl_domhsh_remove(const char *domain)
+int netlbl_domhsh_remove(const char *domain, u32 audit_secid)
 {
         int ret_val = -ENOENT;
         struct netlbl_dom_map *entry;
+        struct audit_buffer *audit_buf;
+        char *audit_domain;
 
         rcu_read_lock();
         if (domain != NULL)
@@ -316,8 +345,18 @@ int netlbl_domhsh_remove(const char *domain)
                         ret_val = -ENOENT;
                 spin_unlock(&netlbl_domhsh_def_lock);
         }
-        if (ret_val == 0)
+        if (ret_val == 0) {
+                if (entry->domain != NULL)
+                        audit_domain = entry->domain;
+                else
+                        audit_domain = "(default)";
+                audit_buf = netlbl_audit_start_common(AUDIT_MAC_MAP_DEL,
+                                                      audit_secid);
+                audit_log_format(audit_buf, " domain=%s", audit_domain);
+                audit_log_end(audit_buf);
+
                 call_rcu(&entry->rcu, netlbl_domhsh_free_entry);
+        }
 
 remove_return:
         rcu_read_unlock();
@@ -326,6 +365,7 @@ remove_return:
 
 /**
  * netlbl_domhsh_remove_default - Removes the default entry from the table
+ * @audit_secid: the LSM secid to use in the audit message
  *
  * Description:
  * Removes/resets the default entry for the domain hash table and handles any
@@ -333,9 +373,9 @@ remove_return:
  * success, non-zero on failure.
  *
  */
-int netlbl_domhsh_remove_default(void)
+int netlbl_domhsh_remove_default(u32 audit_secid)
 {
-        return netlbl_domhsh_remove(NULL);
+        return netlbl_domhsh_remove(NULL, audit_secid);
 }
 
 /**
diff --git a/net/netlabel/netlabel_domainhash.h b/net/netlabel/netlabel_domainhash.h
index 02af72a7877c..d50f13cacdca 100644
--- a/net/netlabel/netlabel_domainhash.h
+++ b/net/netlabel/netlabel_domainhash.h
@@ -57,9 +57,9 @@ struct netlbl_dom_map {
 int netlbl_domhsh_init(u32 size);
 
 /* Manipulate the domain hash table */
-int netlbl_domhsh_add(struct netlbl_dom_map *entry);
-int netlbl_domhsh_add_default(struct netlbl_dom_map *entry);
-int netlbl_domhsh_remove_default(void);
+int netlbl_domhsh_add(struct netlbl_dom_map *entry, u32 audit_secid);
+int netlbl_domhsh_add_default(struct netlbl_dom_map *entry, u32 audit_secid);
+int netlbl_domhsh_remove_default(u32 audit_secid);
 struct netlbl_dom_map *netlbl_domhsh_getentry(const char *domain);
 int netlbl_domhsh_walk(u32 *skip_bkt,
                      u32 *skip_chain,
diff --git a/net/netlabel/netlabel_mgmt.c b/net/netlabel/netlabel_mgmt.c
index 8626c9f678eb..0ac314f18ad1 100644
--- a/net/netlabel/netlabel_mgmt.c
+++ b/net/netlabel/netlabel_mgmt.c
@@ -108,7 +108,7 @@ static int netlbl_mgmt_add(struct sk_buff *skb, struct genl_info *info)
 
         switch (entry->type) {
         case NETLBL_NLTYPE_UNLABELED:
-                ret_val = netlbl_domhsh_add(entry);
+                ret_val = netlbl_domhsh_add(entry, NETLINK_CB(skb).sid);
                 break;
         case NETLBL_NLTYPE_CIPSOV4:
                 if (!info->attrs[NLBL_MGMT_A_CV4DOI])
@@ -125,7 +125,7 @@ static int netlbl_mgmt_add(struct sk_buff *skb, struct genl_info *info)
                         rcu_read_unlock();
                         goto add_failure;
                 }
-                ret_val = netlbl_domhsh_add(entry);
+                ret_val = netlbl_domhsh_add(entry, NETLINK_CB(skb).sid);
                 rcu_read_unlock();
                 break;
         default:
@@ -161,7 +161,7 @@ static int netlbl_mgmt_remove(struct sk_buff *skb, struct genl_info *info)
                 return -EINVAL;
 
         domain = nla_data(info->attrs[NLBL_MGMT_A_DOMAIN]);
-        return netlbl_domhsh_remove(domain);
+        return netlbl_domhsh_remove(domain, NETLINK_CB(skb).sid);
 }
 
 /**
@@ -277,7 +277,8 @@ static int netlbl_mgmt_adddef(struct sk_buff *skb, struct genl_info *info)
 
         switch (entry->type) {
         case NETLBL_NLTYPE_UNLABELED:
-                ret_val = netlbl_domhsh_add_default(entry);
+                ret_val = netlbl_domhsh_add_default(entry,
+                                                    NETLINK_CB(skb).sid);
                 break;
         case NETLBL_NLTYPE_CIPSOV4:
                 if (!info->attrs[NLBL_MGMT_A_CV4DOI])
@@ -294,7 +295,8 @@ static int netlbl_mgmt_adddef(struct sk_buff *skb, struct genl_info *info)
                         rcu_read_unlock();
                         goto adddef_failure;
                 }
-                ret_val = netlbl_domhsh_add_default(entry);
+                ret_val = netlbl_domhsh_add_default(entry,
+                                                    NETLINK_CB(skb).sid);
                 rcu_read_unlock();
                 break;
         default:
@@ -322,7 +324,7 @@ adddef_failure:
  */
 static int netlbl_mgmt_removedef(struct sk_buff *skb, struct genl_info *info)
 {
-        return netlbl_domhsh_remove_default();
+        return netlbl_domhsh_remove_default(NETLINK_CB(skb).sid);
 }
 
 /**
diff --git a/net/netlabel/netlabel_unlabeled.c b/net/netlabel/netlabel_unlabeled.c
index 440f5c4e1e2d..ab36675fee8c 100644
--- a/net/netlabel/netlabel_unlabeled.c
+++ b/net/netlabel/netlabel_unlabeled.c
@@ -64,6 +64,27 @@ static struct nla_policy netlbl_unlabel_genl_policy[NLBL_UNLABEL_A_MAX + 1] = {
 };
 
 /*
+ * Helper Functions
+ */
+
+/**
+ * netlbl_unlabel_acceptflg_set - Set the unlabeled accept flag
+ * @value: desired value
+ * @audit_secid: the LSM secid to use in the audit message
+ *
+ * Description:
+ * Set the value of the unlabeled accept flag to @value.
+ *
+ */
+static void netlbl_unlabel_acceptflg_set(u8 value, u32 audit_secid)
+{
+        atomic_set(&netlabel_unlabel_accept_flg, value);
+        netlbl_audit_nomsg((value ?
+                            AUDIT_MAC_UNLBL_ACCEPT : AUDIT_MAC_UNLBL_DENY),
+                           audit_secid);
+}
+
+/*
  * NetLabel Command Handlers
  */
 
@@ -79,18 +100,18 @@ static struct nla_policy netlbl_unlabel_genl_policy[NLBL_UNLABEL_A_MAX + 1] = {
  */
 static int netlbl_unlabel_accept(struct sk_buff *skb, struct genl_info *info)
 {
-        int ret_val = -EINVAL;
         u8 value;
 
         if (info->attrs[NLBL_UNLABEL_A_ACPTFLG]) {
                 value = nla_get_u8(info->attrs[NLBL_UNLABEL_A_ACPTFLG]);
                 if (value == 1 || value == 0) {
-                        atomic_set(&netlabel_unlabel_accept_flg, value);
-                        ret_val = 0;
+                        netlbl_unlabel_acceptflg_set(value,
+                                                     NETLINK_CB(skb).sid);
+                        return 0;
                 }
         }
 
-        return ret_val;
+        return -EINVAL;
 }
 
 /**
@@ -229,16 +250,19 @@ int netlbl_unlabel_defconf(void)
 {
         int ret_val;
         struct netlbl_dom_map *entry;
+        u32 secid;
+
+        security_task_getsecid(current, &secid);
 
         entry = kzalloc(sizeof(*entry), GFP_KERNEL);
         if (entry == NULL)
                 return -ENOMEM;
         entry->type = NETLBL_NLTYPE_UNLABELED;
-        ret_val = netlbl_domhsh_add_default(entry);
+        ret_val = netlbl_domhsh_add_default(entry, secid);
         if (ret_val != 0)
                 return ret_val;
 
-        atomic_set(&netlabel_unlabel_accept_flg, 1);
+        netlbl_unlabel_acceptflg_set(1, secid);
 
         return 0;
 }
diff --git a/net/netlabel/netlabel_user.c b/net/netlabel/netlabel_user.c
index eeb7d768d2bb..c2343af584cb 100644
--- a/net/netlabel/netlabel_user.c
+++ b/net/netlabel/netlabel_user.c
@@ -32,6 +32,9 @@
 #include <linux/types.h>
 #include <linux/list.h>
 #include <linux/socket.h>
+#include <linux/audit.h>
+#include <linux/tty.h>
+#include <linux/security.h>
 #include <net/sock.h>
 #include <net/netlink.h>
 #include <net/genetlink.h>
@@ -74,3 +77,91 @@ int netlbl_netlink_init(void)
 
         return 0;
 }
+
+/*
+ * NetLabel Audit Functions
+ */
+
+/**
+ * netlbl_audit_start_common - Start an audit message
+ * @type: audit message type
+ * @secid: LSM context ID
+ *
+ * Description:
+ * Start an audit message using the type specified in @type and fill the audit
+ * message with some fields common to all NetLabel audit messages.  Returns
+ * a pointer to the audit buffer on success, NULL on failure.
+ *
+ */
+struct audit_buffer *netlbl_audit_start_common(int type, u32 secid)
+{
+        struct audit_context *audit_ctx = current->audit_context;
+        struct audit_buffer *audit_buf;
+        uid_t audit_loginuid;
+        const char *audit_tty;
+        char audit_comm[sizeof(current->comm)];
+        struct vm_area_struct *vma;
+        char *secctx;
+        u32 secctx_len;
+
+        audit_buf = audit_log_start(audit_ctx, GFP_ATOMIC, type);
+        if (audit_buf == NULL)
+                return NULL;
+
+        audit_loginuid = audit_get_loginuid(audit_ctx);
+        if (current->signal &&
+            current->signal->tty &&
+            current->signal->tty->name)
+                audit_tty = current->signal->tty->name;
+        else
+                audit_tty = "(none)";
+        get_task_comm(audit_comm, current);
+
+        audit_log_format(audit_buf,
+                         "netlabel: auid=%u uid=%u tty=%s pid=%d",
+                         audit_loginuid,
+                         current->uid,
+                         audit_tty,
+                         current->pid);
+        audit_log_format(audit_buf, " comm=");
+        audit_log_untrustedstring(audit_buf, audit_comm);
+        if (current->mm) {
+                down_read(&current->mm->mmap_sem);
+                vma = current->mm->mmap;
+                while (vma) {
+                        if ((vma->vm_flags & VM_EXECUTABLE) &&
+                            vma->vm_file) {
+                                audit_log_d_path(audit_buf,
+                                                 " exe=",
+                                                 vma->vm_file->f_dentry,
+                                                 vma->vm_file->f_vfsmnt);
+                                break;
+                        }
+                        vma = vma->vm_next;
+                }
+                up_read(&current->mm->mmap_sem);
+        }
+
+        if (secid != 0 &&
+            security_secid_to_secctx(secid, &secctx, &secctx_len) == 0)
+                audit_log_format(audit_buf, " subj=%s", secctx);
+
+        return audit_buf;
+}
+
+/**
+ * netlbl_audit_nomsg - Send an audit message without additional text
+ * @type: audit message type
+ * @secid: LSM context ID
+ *
+ * Description:
+ * Send an audit message with only the common NetLabel audit fields.
+ *
+ */
+void netlbl_audit_nomsg(int type, u32 secid)
+{
+        struct audit_buffer *audit_buf;
+
+        audit_buf = netlbl_audit_start_common(type, secid);
+        audit_log_end(audit_buf);
+}
diff --git a/net/netlabel/netlabel_user.h b/net/netlabel/netlabel_user.h
index 3f9386b917df..ab840acfc964 100644
--- a/net/netlabel/netlabel_user.h
+++ b/net/netlabel/netlabel_user.h
@@ -34,6 +34,7 @@
 #include <linux/types.h>
 #include <linux/skbuff.h>
 #include <linux/capability.h>
+#include <linux/audit.h>
 #include <net/netlink.h>
 #include <net/genetlink.h>
 #include <net/netlabel.h>
@@ -75,4 +76,9 @@ static inline void *netlbl_netlink_hdr_put(struct sk_buff *skb,
 
 int netlbl_netlink_init(void);
 
+/* NetLabel Audit Functions */
+
+struct audit_buffer *netlbl_audit_start_common(int type, u32 secid);
+void netlbl_audit_nomsg(int type, u32 secid);
+
 #endif