Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux...
[cascardo/linux.git] / security / smack / smackfs.c
index 2716d02..c20b154 100644 (file)
@@ -29,6 +29,7 @@
 #include <linux/magic.h>
 #include "smack.h"
 
+#define BEBITS (sizeof(__be32) * 8)
 /*
  * smackfs pseudo filesystem.
  */
@@ -40,7 +41,7 @@ enum smk_inos {
        SMK_DOI         = 5,    /* CIPSO DOI */
        SMK_DIRECT      = 6,    /* CIPSO level indicating direct label */
        SMK_AMBIENT     = 7,    /* internet ambient label */
-       SMK_NETLBLADDR  = 8,    /* single label hosts */
+       SMK_NET4ADDR    = 8,    /* single label hosts */
        SMK_ONLYCAP     = 9,    /* the only "capable" label */
        SMK_LOGGING     = 10,   /* logging */
        SMK_LOAD_SELF   = 11,   /* task specific rules */
@@ -57,6 +58,9 @@ enum smk_inos {
 #ifdef CONFIG_SECURITY_SMACK_BRINGUP
        SMK_UNCONFINED  = 22,   /* define an unconfined label */
 #endif
+#if IS_ENABLED(CONFIG_IPV6)
+       SMK_NET6ADDR    = 23,   /* single label IPv6 hosts */
+#endif /* CONFIG_IPV6 */
 };
 
 /*
@@ -64,7 +68,10 @@ enum smk_inos {
  */
 static DEFINE_MUTEX(smack_cipso_lock);
 static DEFINE_MUTEX(smack_ambient_lock);
-static DEFINE_MUTEX(smk_netlbladdr_lock);
+static DEFINE_MUTEX(smk_net4addr_lock);
+#if IS_ENABLED(CONFIG_IPV6)
+static DEFINE_MUTEX(smk_net6addr_lock);
+#endif /* CONFIG_IPV6 */
 
 /*
  * This is the "ambient" label for network traffic.
@@ -118,7 +125,10 @@ int smack_ptrace_rule = SMACK_PTRACE_DEFAULT;
  * can write to the specified label.
  */
 
-LIST_HEAD(smk_netlbladdr_list);
+LIST_HEAD(smk_net4addr_list);
+#if IS_ENABLED(CONFIG_IPV6)
+LIST_HEAD(smk_net6addr_list);
+#endif /* CONFIG_IPV6 */
 
 /*
  * Rule lists are maintained for each label.
@@ -129,7 +139,7 @@ struct smack_master_list {
        struct smack_rule       *smk_rule;
 };
 
-LIST_HEAD(smack_rule_list);
+static LIST_HEAD(smack_rule_list);
 
 struct smack_parsed_rule {
        struct smack_known      *smk_subject;
@@ -140,11 +150,6 @@ struct smack_parsed_rule {
 
 static int smk_cipso_doi_value = SMACK_CIPSO_DOI_DEFAULT;
 
-struct smack_known smack_cipso_option = {
-       .smk_known      = SMACK_CIPSO_OPTION,
-       .smk_secid      = 0,
-};
-
 /*
  * Values for parsing cipso rules
  * SMK_DIGITLEN: Length of a digit field in a rule.
@@ -1047,92 +1052,90 @@ static const struct file_operations smk_cipso2_ops = {
  * Seq_file read operations for /smack/netlabel
  */
 
-static void *netlbladdr_seq_start(struct seq_file *s, loff_t *pos)
+static void *net4addr_seq_start(struct seq_file *s, loff_t *pos)
 {
-       return smk_seq_start(s, pos, &smk_netlbladdr_list);
+       return smk_seq_start(s, pos, &smk_net4addr_list);
 }
 
-static void *netlbladdr_seq_next(struct seq_file *s, void *v, loff_t *pos)
+static void *net4addr_seq_next(struct seq_file *s, void *v, loff_t *pos)
 {
-       return smk_seq_next(s, v, pos, &smk_netlbladdr_list);
+       return smk_seq_next(s, v, pos, &smk_net4addr_list);
 }
-#define BEBITS (sizeof(__be32) * 8)
 
 /*
  * Print host/label pairs
  */
-static int netlbladdr_seq_show(struct seq_file *s, void *v)
+static int net4addr_seq_show(struct seq_file *s, void *v)
 {
        struct list_head *list = v;
-       struct smk_netlbladdr *skp =
-                       list_entry_rcu(list, struct smk_netlbladdr, list);
-       unsigned char *hp = (char *) &skp->smk_host.sin_addr.s_addr;
-       int maskn;
-       u32 temp_mask = be32_to_cpu(skp->smk_mask.s_addr);
-
-       for (maskn = 0; temp_mask; temp_mask <<= 1, maskn++);
+       struct smk_net4addr *skp =
+                       list_entry_rcu(list, struct smk_net4addr, list);
+       char *kp = SMACK_CIPSO_OPTION;
 
-       seq_printf(s, "%u.%u.%u.%u/%d %s\n",
-               hp[0], hp[1], hp[2], hp[3], maskn, skp->smk_label->smk_known);
+       if (skp->smk_label != NULL)
+               kp = skp->smk_label->smk_known;
+       seq_printf(s, "%pI4/%d %s\n", &skp->smk_host.s_addr,
+                       skp->smk_masks, kp);
 
        return 0;
 }
 
-static const struct seq_operations netlbladdr_seq_ops = {
-       .start = netlbladdr_seq_start,
-       .next  = netlbladdr_seq_next,
-       .show  = netlbladdr_seq_show,
+static const struct seq_operations net4addr_seq_ops = {
+       .start = net4addr_seq_start,
+       .next  = net4addr_seq_next,
+       .show  = net4addr_seq_show,
        .stop  = smk_seq_stop,
 };
 
 /**
- * smk_open_netlbladdr - open() for /smack/netlabel
+ * smk_open_net4addr - open() for /smack/netlabel
  * @inode: inode structure representing file
  * @file: "netlabel" file pointer
  *
- * Connect our netlbladdr_seq_* operations with /smack/netlabel
+ * Connect our net4addr_seq_* operations with /smack/netlabel
  * file_operations
  */
-static int smk_open_netlbladdr(struct inode *inode, struct file *file)
+static int smk_open_net4addr(struct inode *inode, struct file *file)
 {
-       return seq_open(file, &netlbladdr_seq_ops);
+       return seq_open(file, &net4addr_seq_ops);
 }
 
 /**
- * smk_netlbladdr_insert
+ * smk_net4addr_insert
  * @new : netlabel to insert
  *
- * This helper insert netlabel in the smack_netlbladdrs list
+ * This helper insert netlabel in the smack_net4addrs list
  * sorted by netmask length (longest to smallest)
- * locked by &smk_netlbladdr_lock in smk_write_netlbladdr
+ * locked by &smk_net4addr_lock in smk_write_net4addr
  *
  */
-static void smk_netlbladdr_insert(struct smk_netlbladdr *new)
+static void smk_net4addr_insert(struct smk_net4addr *new)
 {
-       struct smk_netlbladdr *m, *m_next;
+       struct smk_net4addr *m;
+       struct smk_net4addr *m_next;
 
-       if (list_empty(&smk_netlbladdr_list)) {
-               list_add_rcu(&new->list, &smk_netlbladdr_list);
+       if (list_empty(&smk_net4addr_list)) {
+               list_add_rcu(&new->list, &smk_net4addr_list);
                return;
        }
 
-       m = list_entry_rcu(smk_netlbladdr_list.next,
-                          struct smk_netlbladdr, list);
+       m = list_entry_rcu(smk_net4addr_list.next,
+                          struct smk_net4addr, list);
 
        /* the comparison '>' is a bit hacky, but works */
-       if (new->smk_mask.s_addr > m->smk_mask.s_addr) {
-               list_add_rcu(&new->list, &smk_netlbladdr_list);
+       if (new->smk_masks > m->smk_masks) {
+               list_add_rcu(&new->list, &smk_net4addr_list);
                return;
        }
 
-       list_for_each_entry_rcu(m, &smk_netlbladdr_list, list) {
-               if (list_is_last(&m->list, &smk_netlbladdr_list)) {
+       list_for_each_entry_rcu(m, &smk_net4addr_list, list) {
+               if (list_is_last(&m->list, &smk_net4addr_list)) {
                        list_add_rcu(&new->list, &m->list);
                        return;
                }
                m_next = list_entry_rcu(m->list.next,
-                                       struct smk_netlbladdr, list);
-               if (new->smk_mask.s_addr > m_next->smk_mask.s_addr) {
+                                       struct smk_net4addr, list);
+               if (new->smk_masks > m_next->smk_masks) {
                        list_add_rcu(&new->list, &m->list);
                        return;
                }
@@ -1141,28 +1144,29 @@ static void smk_netlbladdr_insert(struct smk_netlbladdr *new)
 
 
 /**
- * smk_write_netlbladdr - write() for /smack/netlabel
+ * smk_write_net4addr - write() for /smack/netlabel
  * @file: file pointer, not actually used
  * @buf: where to get the data from
  * @count: bytes sent
  * @ppos: where to start
  *
- * Accepts only one netlbladdr per write call.
+ * Accepts only one net4addr per write call.
  * Returns number of bytes written or error code, as appropriate
  */
-static ssize_t smk_write_netlbladdr(struct file *file, const char __user *buf,
+static ssize_t smk_write_net4addr(struct file *file, const char __user *buf,
                                size_t count, loff_t *ppos)
 {
-       struct smk_netlbladdr *snp;
+       struct smk_net4addr *snp;
        struct sockaddr_in newname;
        char *smack;
-       struct smack_known *skp;
+       struct smack_known *skp = NULL;
        char *data;
        char *host = (char *)&newname.sin_addr.s_addr;
        int rc;
        struct netlbl_audit audit_info;
        struct in_addr mask;
        unsigned int m;
+       unsigned int masks;
        int found;
        u32 mask_bits = (1<<31);
        __be32 nsa;
@@ -1200,7 +1204,7 @@ static ssize_t smk_write_netlbladdr(struct file *file, const char __user *buf,
        data[count] = '\0';
 
        rc = sscanf(data, "%hhd.%hhd.%hhd.%hhd/%u %s",
-               &host[0], &host[1], &host[2], &host[3], &m, smack);
+               &host[0], &host[1], &host[2], &host[3], &masks, smack);
        if (rc != 6) {
                rc = sscanf(data, "%hhd.%hhd.%hhd.%hhd %s",
                        &host[0], &host[1], &host[2], &host[3], smack);
@@ -1209,8 +1213,9 @@ static ssize_t smk_write_netlbladdr(struct file *file, const char __user *buf,
                        goto free_out;
                }
                m = BEBITS;
+               masks = 32;
        }
-       if (m > BEBITS) {
+       if (masks > BEBITS) {
                rc = -EINVAL;
                goto free_out;
        }
@@ -1225,16 +1230,16 @@ static ssize_t smk_write_netlbladdr(struct file *file, const char __user *buf,
                        goto free_out;
                }
        } else {
-               /* check known options */
-               if (strcmp(smack, smack_cipso_option.smk_known) == 0)
-                       skp = &smack_cipso_option;
-               else {
+               /*
+                * Only the -CIPSO option is supported for IPv4
+                */
+               if (strcmp(smack, SMACK_CIPSO_OPTION) != 0) {
                        rc = -EINVAL;
                        goto free_out;
                }
        }
 
-       for (temp_mask = 0; m > 0; m--) {
+       for (m = masks, temp_mask = 0; m > 0; m--) {
                temp_mask |= mask_bits;
                mask_bits >>= 1;
        }
@@ -1245,14 +1250,13 @@ static ssize_t smk_write_netlbladdr(struct file *file, const char __user *buf,
         * Only allow one writer at a time. Writes should be
         * quite rare and small in any case.
         */
-       mutex_lock(&smk_netlbladdr_lock);
+       mutex_lock(&smk_net4addr_lock);
 
        nsa = newname.sin_addr.s_addr;
        /* try to find if the prefix is already in the list */
        found = 0;
-       list_for_each_entry_rcu(snp, &smk_netlbladdr_list, list) {
-               if (snp->smk_host.sin_addr.s_addr == nsa &&
-                   snp->smk_mask.s_addr == mask.s_addr) {
+       list_for_each_entry_rcu(snp, &smk_net4addr_list, list) {
+               if (snp->smk_host.s_addr == nsa && snp->smk_masks == masks) {
                        found = 1;
                        break;
                }
@@ -1265,17 +1269,20 @@ static ssize_t smk_write_netlbladdr(struct file *file, const char __user *buf,
                        rc = -ENOMEM;
                else {
                        rc = 0;
-                       snp->smk_host.sin_addr.s_addr = newname.sin_addr.s_addr;
+                       snp->smk_host.s_addr = newname.sin_addr.s_addr;
                        snp->smk_mask.s_addr = mask.s_addr;
                        snp->smk_label = skp;
-                       smk_netlbladdr_insert(snp);
+                       snp->smk_masks = masks;
+                       smk_net4addr_insert(snp);
                }
        } else {
-               /* we delete the unlabeled entry, only if the previous label
-                * wasn't the special CIPSO option */
-               if (snp->smk_label != &smack_cipso_option)
+               /*
+                * Delete the unlabeled entry, only if the previous label
+                * wasn't the special CIPSO option
+                */
+               if (snp->smk_label != NULL)
                        rc = netlbl_cfg_unlbl_static_del(&init_net, NULL,
-                                       &snp->smk_host.sin_addr, &snp->smk_mask,
+                                       &snp->smk_host, &snp->smk_mask,
                                        PF_INET, &audit_info);
                else
                        rc = 0;
@@ -1287,15 +1294,15 @@ static ssize_t smk_write_netlbladdr(struct file *file, const char __user *buf,
         * this host so that incoming packets get labeled.
         * but only if we didn't get the special CIPSO option
         */
-       if (rc == 0 && skp != &smack_cipso_option)
+       if (rc == 0 && skp != NULL)
                rc = netlbl_cfg_unlbl_static_add(&init_net, NULL,
-                       &snp->smk_host.sin_addr, &snp->smk_mask, PF_INET,
+                       &snp->smk_host, &snp->smk_mask, PF_INET,
                        snp->smk_label->smk_secid, &audit_info);
 
        if (rc == 0)
                rc = count;
 
-       mutex_unlock(&smk_netlbladdr_lock);
+       mutex_unlock(&smk_net4addr_lock);
 
 free_out:
        kfree(smack);
@@ -1305,14 +1312,279 @@ free_data_out:
        return rc;
 }
 
-static const struct file_operations smk_netlbladdr_ops = {
-       .open           = smk_open_netlbladdr,
+static const struct file_operations smk_net4addr_ops = {
+       .open           = smk_open_net4addr,
        .read           = seq_read,
        .llseek         = seq_lseek,
-       .write          = smk_write_netlbladdr,
+       .write          = smk_write_net4addr,
        .release        = seq_release,
 };
 
+#if IS_ENABLED(CONFIG_IPV6)
+/*
+ * Seq_file read operations for /smack/netlabel6
+ */
+
+static void *net6addr_seq_start(struct seq_file *s, loff_t *pos)
+{
+       return smk_seq_start(s, pos, &smk_net6addr_list);
+}
+
+static void *net6addr_seq_next(struct seq_file *s, void *v, loff_t *pos)
+{
+       return smk_seq_next(s, v, pos, &smk_net6addr_list);
+}
+
+/*
+ * Print host/label pairs
+ */
+static int net6addr_seq_show(struct seq_file *s, void *v)
+{
+       struct list_head *list = v;
+       struct smk_net6addr *skp =
+                        list_entry(list, struct smk_net6addr, list);
+
+       if (skp->smk_label != NULL)
+               seq_printf(s, "%pI6/%d %s\n", &skp->smk_host, skp->smk_masks,
+                               skp->smk_label->smk_known);
+
+       return 0;
+}
+
+static const struct seq_operations net6addr_seq_ops = {
+       .start = net6addr_seq_start,
+       .next  = net6addr_seq_next,
+       .show  = net6addr_seq_show,
+       .stop  = smk_seq_stop,
+};
+
+/**
+ * smk_open_net6addr - open() for /smack/netlabel
+ * @inode: inode structure representing file
+ * @file: "netlabel" file pointer
+ *
+ * Connect our net6addr_seq_* operations with /smack/netlabel
+ * file_operations
+ */
+static int smk_open_net6addr(struct inode *inode, struct file *file)
+{
+       return seq_open(file, &net6addr_seq_ops);
+}
+
+/**
+ * smk_net6addr_insert
+ * @new : entry to insert
+ *
+ * This inserts an entry in the smack_net6addrs list
+ * sorted by netmask length (longest to smallest)
+ * locked by &smk_net6addr_lock in smk_write_net6addr
+ *
+ */
+static void smk_net6addr_insert(struct smk_net6addr *new)
+{
+       struct smk_net6addr *m_next;
+       struct smk_net6addr *m;
+
+       if (list_empty(&smk_net6addr_list)) {
+               list_add_rcu(&new->list, &smk_net6addr_list);
+               return;
+       }
+
+       m = list_entry_rcu(smk_net6addr_list.next,
+                          struct smk_net6addr, list);
+
+       if (new->smk_masks > m->smk_masks) {
+               list_add_rcu(&new->list, &smk_net6addr_list);
+               return;
+       }
+
+       list_for_each_entry_rcu(m, &smk_net6addr_list, list) {
+               if (list_is_last(&m->list, &smk_net6addr_list)) {
+                       list_add_rcu(&new->list, &m->list);
+                       return;
+               }
+               m_next = list_entry_rcu(m->list.next,
+                                       struct smk_net6addr, list);
+               if (new->smk_masks > m_next->smk_masks) {
+                       list_add_rcu(&new->list, &m->list);
+                       return;
+               }
+       }
+}
+
+
+/**
+ * smk_write_net6addr - write() for /smack/netlabel
+ * @file: file pointer, not actually used
+ * @buf: where to get the data from
+ * @count: bytes sent
+ * @ppos: where to start
+ *
+ * Accepts only one net6addr per write call.
+ * Returns number of bytes written or error code, as appropriate
+ */
+static ssize_t smk_write_net6addr(struct file *file, const char __user *buf,
+                               size_t count, loff_t *ppos)
+{
+       struct smk_net6addr *snp;
+       struct in6_addr newname;
+       struct in6_addr fullmask;
+       struct smack_known *skp = NULL;
+       char *smack;
+       char *data;
+       int rc = 0;
+       int found = 0;
+       int i;
+       unsigned int scanned[8];
+       unsigned int m;
+       unsigned int mask = 128;
+
+       /*
+        * Must have privilege.
+        * No partial writes.
+        * Enough data must be present.
+        * "<addr/mask, as a:b:c:d:e:f:g:h/e><space><label>"
+        * "<addr, as a:b:c:d:e:f:g:h><space><label>"
+        */
+       if (!smack_privileged(CAP_MAC_ADMIN))
+               return -EPERM;
+       if (*ppos != 0)
+               return -EINVAL;
+       if (count < SMK_NETLBLADDRMIN)
+               return -EINVAL;
+
+       data = kzalloc(count + 1, GFP_KERNEL);
+       if (data == NULL)
+               return -ENOMEM;
+
+       if (copy_from_user(data, buf, count) != 0) {
+               rc = -EFAULT;
+               goto free_data_out;
+       }
+
+       smack = kzalloc(count + 1, GFP_KERNEL);
+       if (smack == NULL) {
+               rc = -ENOMEM;
+               goto free_data_out;
+       }
+
+       data[count] = '\0';
+
+       i = sscanf(data, "%x:%x:%x:%x:%x:%x:%x:%x/%u %s",
+                       &scanned[0], &scanned[1], &scanned[2], &scanned[3],
+                       &scanned[4], &scanned[5], &scanned[6], &scanned[7],
+                       &mask, smack);
+       if (i != 10) {
+               i = sscanf(data, "%x:%x:%x:%x:%x:%x:%x:%x %s",
+                               &scanned[0], &scanned[1], &scanned[2],
+                               &scanned[3], &scanned[4], &scanned[5],
+                               &scanned[6], &scanned[7], smack);
+               if (i != 9) {
+                       rc = -EINVAL;
+                       goto free_out;
+               }
+       }
+       if (mask > 128) {
+               rc = -EINVAL;
+               goto free_out;
+       }
+       for (i = 0; i < 8; i++) {
+               if (scanned[i] > 0xffff) {
+                       rc = -EINVAL;
+                       goto free_out;
+               }
+               newname.s6_addr16[i] = htons(scanned[i]);
+       }
+
+       /*
+        * If smack begins with '-', it is an option, don't import it
+        */
+       if (smack[0] != '-') {
+               skp = smk_import_entry(smack, 0);
+               if (skp == NULL) {
+                       rc = -EINVAL;
+                       goto free_out;
+               }
+       } else {
+               /*
+                * Only -DELETE is supported for IPv6
+                */
+               if (strcmp(smack, SMACK_DELETE_OPTION) != 0) {
+                       rc = -EINVAL;
+                       goto free_out;
+               }
+       }
+
+       for (i = 0, m = mask; i < 8; i++) {
+               if (m >= 16) {
+                       fullmask.s6_addr16[i] = 0xffff;
+                       m -= 16;
+               } else if (m > 0) {
+                       fullmask.s6_addr16[i] = (1 << m) - 1;
+                       m = 0;
+               } else
+                       fullmask.s6_addr16[i] = 0;
+               newname.s6_addr16[i] &= fullmask.s6_addr16[i];
+       }
+
+       /*
+        * Only allow one writer at a time. Writes should be
+        * quite rare and small in any case.
+        */
+       mutex_lock(&smk_net6addr_lock);
+       /*
+        * Try to find the prefix in the list
+        */
+       list_for_each_entry_rcu(snp, &smk_net6addr_list, list) {
+               if (mask != snp->smk_masks)
+                       continue;
+               for (found = 1, i = 0; i < 8; i++) {
+                       if (newname.s6_addr16[i] !=
+                           snp->smk_host.s6_addr16[i]) {
+                               found = 0;
+                               break;
+                       }
+               }
+               if (found == 1)
+                       break;
+       }
+       if (found == 0) {
+               snp = kzalloc(sizeof(*snp), GFP_KERNEL);
+               if (snp == NULL)
+                       rc = -ENOMEM;
+               else {
+                       snp->smk_host = newname;
+                       snp->smk_mask = fullmask;
+                       snp->smk_masks = mask;
+                       snp->smk_label = skp;
+                       smk_net6addr_insert(snp);
+               }
+       } else {
+               snp->smk_label = skp;
+       }
+
+       if (rc == 0)
+               rc = count;
+
+       mutex_unlock(&smk_net6addr_lock);
+
+free_out:
+       kfree(smack);
+free_data_out:
+       kfree(data);
+
+       return rc;
+}
+
+static const struct file_operations smk_net6addr_ops = {
+       .open           = smk_open_net6addr,
+       .read           = seq_read,
+       .llseek         = seq_lseek,
+       .write          = smk_write_net6addr,
+       .release        = seq_release,
+};
+#endif /* CONFIG_IPV6 */
+
 /**
  * smk_read_doi - read() for /smack/doi
  * @filp: file pointer, not actually used
@@ -2320,11 +2592,7 @@ static const struct file_operations smk_revoke_subj_ops = {
  */
 static int smk_init_sysfs(void)
 {
-       int err;
-       err = sysfs_create_mount_point(fs_kobj, "smackfs");
-       if (err)
-               return err;
-       return 0;
+       return sysfs_create_mount_point(fs_kobj, "smackfs");
 }
 
 /**
@@ -2519,8 +2787,8 @@ static int smk_fill_super(struct super_block *sb, void *data, int silent)
                        "direct", &smk_direct_ops, S_IRUGO|S_IWUSR},
                [SMK_AMBIENT] = {
                        "ambient", &smk_ambient_ops, S_IRUGO|S_IWUSR},
-               [SMK_NETLBLADDR] = {
-                       "netlabel", &smk_netlbladdr_ops, S_IRUGO|S_IWUSR},
+               [SMK_NET4ADDR] = {
+                       "netlabel", &smk_net4addr_ops, S_IRUGO|S_IWUSR},
                [SMK_ONLYCAP] = {
                        "onlycap", &smk_onlycap_ops, S_IRUGO|S_IWUSR},
                [SMK_LOGGING] = {
@@ -2552,6 +2820,10 @@ static int smk_fill_super(struct super_block *sb, void *data, int silent)
                [SMK_UNCONFINED] = {
                        "unconfined", &smk_unconfined_ops, S_IRUGO|S_IWUSR},
 #endif
+#if IS_ENABLED(CONFIG_IPV6)
+               [SMK_NET6ADDR] = {
+                       "ipv6host", &smk_net6addr_ops, S_IRUGO|S_IWUSR},
+#endif /* CONFIG_IPV6 */
                /* last one */
                        {""}
        };