diff options
Diffstat (limited to 'security/smack/smackfs.c')
| -rw-r--r-- | security/smack/smackfs.c | 134 |
1 files changed, 111 insertions, 23 deletions
diff --git a/security/smack/smackfs.c b/security/smack/smackfs.c index 160aa08e3cd5..3198cfe1dcc6 100644 --- a/security/smack/smackfs.c +++ b/security/smack/smackfs.c @@ -52,6 +52,7 @@ enum smk_inos { SMK_CIPSO2 = 17, /* load long label -> CIPSO mapping */ SMK_REVOKE_SUBJ = 18, /* set rules with subject label to '-' */ SMK_CHANGE_RULE = 19, /* change or add rules (long labels) */ + SMK_SYSLOG = 20, /* change syslog label) */ }; /* @@ -59,6 +60,7 @@ enum smk_inos { */ static DEFINE_MUTEX(smack_cipso_lock); static DEFINE_MUTEX(smack_ambient_lock); +static DEFINE_MUTEX(smack_syslog_lock); static DEFINE_MUTEX(smk_netlbladdr_lock); /* @@ -90,7 +92,13 @@ int smack_cipso_mapped = SMACK_CIPSO_MAPPED_DEFAULT; * everyone. It is expected that the hat (^) label * will be used if any label is used. */ -char *smack_onlycap; +struct smack_known *smack_onlycap; + +/* + * If this value is set restrict syslog use to the label specified. + * It can be reset via smackfs/syslog + */ +struct smack_known *smack_syslog_label; /* * Certain IP addresses may be designated as single label hosts. @@ -301,7 +309,8 @@ static int smk_perm_from_str(const char *string) * @import: if non-zero, import labels * @len: label length limit * - * Returns 0 on success, -1 on failure + * Returns 0 on success, -EINVAL on failure and -ENOENT when either subject + * or object is missing. */ static int smk_fill_rule(const char *subject, const char *object, const char *access1, const char *access2, @@ -314,28 +323,28 @@ static int smk_fill_rule(const char *subject, const char *object, if (import) { rule->smk_subject = smk_import_entry(subject, len); if (rule->smk_subject == NULL) - return -1; + return -EINVAL; rule->smk_object = smk_import(object, len); if (rule->smk_object == NULL) - return -1; + return -EINVAL; } else { cp = smk_parse_smack(subject, len); if (cp == NULL) - return -1; + return -EINVAL; skp = smk_find_entry(cp); kfree(cp); if (skp == NULL) - return -1; + return -ENOENT; rule->smk_subject = skp; cp = smk_parse_smack(object, len); if (cp == NULL) - return -1; + return -EINVAL; skp = smk_find_entry(cp); kfree(cp); if (skp == NULL) - return -1; + return -ENOENT; rule->smk_object = skp->smk_known; } @@ -381,6 +390,7 @@ static ssize_t smk_parse_long_rule(char *data, struct smack_parsed_rule *rule, { ssize_t cnt = 0; char *tok[4]; + int rc; int i; /* @@ -405,10 +415,8 @@ static ssize_t smk_parse_long_rule(char *data, struct smack_parsed_rule *rule, while (i < 4) tok[i++] = NULL; - if (smk_fill_rule(tok[0], tok[1], tok[2], tok[3], rule, import, 0)) - return -1; - - return cnt; + rc = smk_fill_rule(tok[0], tok[1], tok[2], tok[3], rule, import, 0); + return rc == 0 ? cnt : rc; } #define SMK_FIXED24_FMT 0 /* Fixed 24byte label format */ @@ -1603,7 +1611,7 @@ static const struct file_operations smk_ambient_ops = { }; /** - * smk_read_onlycap - read() for /smack/onlycap + * smk_read_onlycap - read() for smackfs/onlycap * @filp: file pointer, not actually used * @buf: where to put the result * @cn: maximum to send along @@ -1622,7 +1630,7 @@ static ssize_t smk_read_onlycap(struct file *filp, char __user *buf, return 0; if (smack_onlycap != NULL) - smack = smack_onlycap; + smack = smack_onlycap->smk_known; asize = strlen(smack) + 1; @@ -1633,7 +1641,7 @@ static ssize_t smk_read_onlycap(struct file *filp, char __user *buf, } /** - * smk_write_onlycap - write() for /smack/onlycap + * smk_write_onlycap - write() for smackfs/onlycap * @file: file pointer, not actually used * @buf: where to get the data from * @count: bytes sent @@ -1656,7 +1664,7 @@ static ssize_t smk_write_onlycap(struct file *file, const char __user *buf, * explicitly for clarity. The smk_access() implementation * would use smk_access(smack_onlycap, MAY_WRITE) */ - if (smack_onlycap != NULL && smack_onlycap != skp->smk_known) + if (smack_onlycap != NULL && smack_onlycap != skp) return -EPERM; data = kzalloc(count, GFP_KERNEL); @@ -1676,7 +1684,7 @@ static ssize_t smk_write_onlycap(struct file *file, const char __user *buf, if (copy_from_user(data, buf, count) != 0) rc = -EFAULT; else - smack_onlycap = smk_import(data, count); + smack_onlycap = smk_import_entry(data, count); kfree(data); return rc; @@ -1856,11 +1864,12 @@ static ssize_t smk_user_access(struct file *file, const char __user *buf, res = smk_parse_long_rule(data, &rule, 0, 3); } - if (res < 0) + if (res >= 0) + res = smk_access(rule.smk_subject, rule.smk_object, + rule.smk_access1, NULL); + else if (res != -ENOENT) return -EINVAL; - res = smk_access(rule.smk_subject, rule.smk_object, - rule.smk_access1, NULL); data[0] = res == 0 ? '1' : '0'; data[1] = '\0'; @@ -2143,7 +2152,7 @@ static ssize_t smk_write_change_rule(struct file *file, const char __user *buf, /* * Must have privilege. */ - if (!capable(CAP_MAC_ADMIN)) + if (!smack_privileged(CAP_MAC_ADMIN)) return -EPERM; return smk_write_rules_list(file, buf, count, ppos, NULL, NULL, @@ -2158,12 +2167,89 @@ static const struct file_operations smk_change_rule_ops = { }; /** - * smk_fill_super - fill the /smackfs superblock + * smk_read_syslog - read() for smackfs/syslog + * @filp: file pointer, not actually used + * @buf: where to put the result + * @cn: maximum to send along + * @ppos: where to start + * + * Returns number of bytes read or error code, as appropriate + */ +static ssize_t smk_read_syslog(struct file *filp, char __user *buf, + size_t cn, loff_t *ppos) +{ + struct smack_known *skp; + ssize_t rc = -EINVAL; + int asize; + + if (*ppos != 0) + return 0; + + if (smack_syslog_label == NULL) + skp = &smack_known_star; + else + skp = smack_syslog_label; + + asize = strlen(skp->smk_known) + 1; + + if (cn >= asize) + rc = simple_read_from_buffer(buf, cn, ppos, skp->smk_known, + asize); + + return rc; +} + +/** + * smk_write_syslog - write() for smackfs/syslog + * @file: file pointer, not actually used + * @buf: where to get the data from + * @count: bytes sent + * @ppos: where to start + * + * Returns number of bytes written or error code, as appropriate + */ +static ssize_t smk_write_syslog(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + char *data; + struct smack_known *skp; + int rc = count; + + if (!smack_privileged(CAP_MAC_ADMIN)) + return -EPERM; + + data = kzalloc(count, GFP_KERNEL); + if (data == NULL) + return -ENOMEM; + + if (copy_from_user(data, buf, count) != 0) + rc = -EFAULT; + else { + skp = smk_import_entry(data, count); + if (skp == NULL) + rc = -EINVAL; + else + smack_syslog_label = smk_import_entry(data, count); + } + + kfree(data); + return rc; +} + +static const struct file_operations smk_syslog_ops = { + .read = smk_read_syslog, + .write = smk_write_syslog, + .llseek = default_llseek, +}; + + +/** + * smk_fill_super - fill the smackfs superblock * @sb: the empty superblock * @data: unused * @silent: unused * - * Fill in the well known entries for /smack + * Fill in the well known entries for the smack filesystem * * Returns 0 on success, an error code on failure */ @@ -2208,6 +2294,8 @@ static int smk_fill_super(struct super_block *sb, void *data, int silent) S_IRUGO|S_IWUSR}, [SMK_CHANGE_RULE] = { "change-rule", &smk_change_rule_ops, S_IRUGO|S_IWUSR}, + [SMK_SYSLOG] = { + "syslog", &smk_syslog_ops, S_IRUGO|S_IWUSR}, /* last one */ {""} }; |