diff options
| -rw-r--r-- | security/smack/smack.h | 8 | ||||
| -rw-r--r-- | security/smack/smack_access.c | 43 | ||||
| -rw-r--r-- | security/smack/smack_lsm.c | 52 | ||||
| -rw-r--r-- | security/smack/smackfs.c | 96 |
4 files changed, 182 insertions, 17 deletions
diff --git a/security/smack/smack.h b/security/smack/smack.h index 67ccb7b2b89b..49eada6266ec 100644 --- a/security/smack/smack.h +++ b/security/smack/smack.h @@ -105,6 +105,7 @@ struct task_smack { #define SMK_INODE_INSTANT 0x01 /* inode is instantiated */ #define SMK_INODE_TRANSMUTE 0x02 /* directory is transmuting */ #define SMK_INODE_CHANGED 0x04 /* smack was transmuted */ +#define SMK_INODE_IMPURE 0x08 /* involved in an impure transaction */ /* * A label access rule. @@ -193,6 +194,10 @@ struct smk_port_label { #define MAY_LOCK 0x00002000 /* Locks should be writes, but ... */ #define MAY_BRINGUP 0x00004000 /* Report use of this rule */ +#define SMACK_BRINGUP_ALLOW 1 /* Allow bringup mode */ +#define SMACK_UNCONFINED_SUBJECT 2 /* Allow unconfined label */ +#define SMACK_UNCONFINED_OBJECT 3 /* Allow unconfined label */ + /* * Just to make the common cases easier to deal with */ @@ -254,6 +259,9 @@ extern int smack_cipso_mapped; extern struct smack_known *smack_net_ambient; extern struct smack_known *smack_onlycap; extern struct smack_known *smack_syslog_label; +#ifdef CONFIG_SECURITY_SMACK_BRINGUP +extern struct smack_known *smack_unconfined; +#endif extern struct smack_known smack_cipso_option; extern int smack_ptrace_rule; diff --git a/security/smack/smack_access.c b/security/smack/smack_access.c index 1158430f5bb9..0f410fc56e33 100644 --- a/security/smack/smack_access.c +++ b/security/smack/smack_access.c @@ -130,7 +130,8 @@ int smk_access(struct smack_known *subject, struct smack_known *object, /* * Hardcoded comparisons. - * + */ + /* * A star subject can't access any object. */ if (subject == &smack_known_star) { @@ -189,10 +190,20 @@ int smk_access(struct smack_known *subject, struct smack_known *object, * succeed because of "b" rules. */ if (may & MAY_BRINGUP) - rc = MAY_BRINGUP; + rc = SMACK_BRINGUP_ALLOW; #endif out_audit: + +#ifdef CONFIG_SECURITY_SMACK_BRINGUP + if (rc < 0) { + if (object == smack_unconfined) + rc = SMACK_UNCONFINED_OBJECT; + if (subject == smack_unconfined) + rc = SMACK_UNCONFINED_SUBJECT; + } +#endif + #ifdef CONFIG_AUDIT if (a) smack_log(subject->smk_known, object->smk_known, @@ -338,19 +349,16 @@ static void smack_log_callback(struct audit_buffer *ab, void *a) void smack_log(char *subject_label, char *object_label, int request, int result, struct smk_audit_info *ad) { +#ifdef CONFIG_SECURITY_SMACK_BRINGUP + char request_buffer[SMK_NUM_ACCESS_TYPE + 5]; +#else char request_buffer[SMK_NUM_ACCESS_TYPE + 1]; +#endif struct smack_audit_data *sad; struct common_audit_data *a = &ad->a; -#ifdef CONFIG_SECURITY_SMACK_BRINGUP - /* - * The result may be positive in bringup mode. - */ - if (result > 0) - result = 0; -#endif /* check if we have to log the current event */ - if (result != 0 && (log_policy & SMACK_AUDIT_DENIED) == 0) + if (result < 0 && (log_policy & SMACK_AUDIT_DENIED) == 0) return; if (result == 0 && (log_policy & SMACK_AUDIT_ACCEPT) == 0) return; @@ -364,6 +372,21 @@ void smack_log(char *subject_label, char *object_label, int request, smack_str_from_perm(request_buffer, request); sad->subject = subject_label; sad->object = object_label; +#ifdef CONFIG_SECURITY_SMACK_BRINGUP + /* + * The result may be positive in bringup mode. + * A positive result is an allow, but not for normal reasons. + * Mark it as successful, but don't filter it out even if + * the logging policy says to do so. + */ + if (result == SMACK_UNCONFINED_SUBJECT) + strcat(request_buffer, "(US)"); + else if (result == SMACK_UNCONFINED_OBJECT) + strcat(request_buffer, "(UO)"); + + if (result > 0) + result = 0; +#endif sad->request = request_buffer; sad->result = result; diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index e2d1a7b073c0..6f3c7d866d04 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -57,6 +57,13 @@ static struct kmem_cache *smack_inode_cache; int smack_enabled; #ifdef CONFIG_SECURITY_SMACK_BRINGUP +static char *smk_bu_mess[] = { + "Bringup Error", /* Unused */ + "Bringup", /* SMACK_BRINGUP_ALLOW */ + "Unconfined Subject", /* SMACK_UNCONFINED_SUBJECT */ + "Unconfined Object", /* SMACK_UNCONFINED_OBJECT */ +}; + static void smk_bu_mode(int mode, char *s) { int i = 0; @@ -87,9 +94,11 @@ static int smk_bu_note(char *note, struct smack_known *sskp, if (rc <= 0) return rc; + if (rc > SMACK_UNCONFINED_OBJECT) + rc = 0; smk_bu_mode(mode, acc); - pr_info("Smack Bringup: (%s %s %s) %s\n", + pr_info("Smack %s: (%s %s %s) %s\n", smk_bu_mess[rc], sskp->smk_known, oskp->smk_known, acc, note); return 0; } @@ -106,9 +115,11 @@ static int smk_bu_current(char *note, struct smack_known *oskp, if (rc <= 0) return rc; + if (rc > SMACK_UNCONFINED_OBJECT) + rc = 0; smk_bu_mode(mode, acc); - pr_info("Smack Bringup: (%s %s %s) %s %s\n", + pr_info("Smack %s: (%s %s %s) %s %s\n", smk_bu_mess[rc], tsp->smk_task->smk_known, oskp->smk_known, acc, current->comm, note); return 0; @@ -126,9 +137,11 @@ static int smk_bu_task(struct task_struct *otp, int mode, int rc) if (rc <= 0) return rc; + if (rc > SMACK_UNCONFINED_OBJECT) + rc = 0; smk_bu_mode(mode, acc); - pr_info("Smack Bringup: (%s %s %s) %s to %s\n", + pr_info("Smack %s: (%s %s %s) %s to %s\n", smk_bu_mess[rc], tsp->smk_task->smk_known, smk_task->smk_known, acc, current->comm, otp->comm); return 0; @@ -141,14 +154,25 @@ static int smk_bu_task(struct task_struct *otp, int mode, int rc) static int smk_bu_inode(struct inode *inode, int mode, int rc) { struct task_smack *tsp = current_security(); + struct inode_smack *isp = inode->i_security; char acc[SMK_NUM_ACCESS_TYPE + 1]; + if (isp->smk_flags & SMK_INODE_IMPURE) + pr_info("Smack Unconfined Corruption: inode=(%s %ld) %s\n", + inode->i_sb->s_id, inode->i_ino, current->comm); + if (rc <= 0) return rc; + if (rc > SMACK_UNCONFINED_OBJECT) + rc = 0; + if (rc == SMACK_UNCONFINED_SUBJECT && + (mode & (MAY_WRITE | MAY_APPEND))) + isp->smk_flags |= SMK_INODE_IMPURE; smk_bu_mode(mode, acc); - pr_info("Smack Bringup: (%s %s %s) inode=(%s %ld) %s\n", - tsp->smk_task->smk_known, smk_of_inode(inode)->smk_known, acc, + + pr_info("Smack %s: (%s %s %s) inode=(%s %ld) %s\n", smk_bu_mess[rc], + tsp->smk_task->smk_known, isp->smk_inode->smk_known, acc, inode->i_sb->s_id, inode->i_ino, current->comm); return 0; } @@ -162,13 +186,20 @@ static int smk_bu_file(struct file *file, int mode, int rc) struct task_smack *tsp = current_security(); struct smack_known *sskp = tsp->smk_task; struct inode *inode = file_inode(file); + struct inode_smack *isp = inode->i_security; char acc[SMK_NUM_ACCESS_TYPE + 1]; + if (isp->smk_flags & SMK_INODE_IMPURE) + pr_info("Smack Unconfined Corruption: inode=(%s %ld) %s\n", + inode->i_sb->s_id, inode->i_ino, current->comm); + if (rc <= 0) return rc; + if (rc > SMACK_UNCONFINED_OBJECT) + rc = 0; smk_bu_mode(mode, acc); - pr_info("Smack Bringup: (%s %s %s) file=(%s %ld %pD) %s\n", + pr_info("Smack %s: (%s %s %s) file=(%s %ld %pD) %s\n", smk_bu_mess[rc], sskp->smk_known, smk_of_inode(inode)->smk_known, acc, inode->i_sb->s_id, inode->i_ino, file, current->comm); @@ -185,13 +216,20 @@ static int smk_bu_credfile(const struct cred *cred, struct file *file, struct task_smack *tsp = cred->security; struct smack_known *sskp = tsp->smk_task; struct inode *inode = file->f_inode; + struct inode_smack *isp = inode->i_security; char acc[SMK_NUM_ACCESS_TYPE + 1]; + if (isp->smk_flags & SMK_INODE_IMPURE) + pr_info("Smack Unconfined Corruption: inode=(%s %ld) %s\n", + inode->i_sb->s_id, inode->i_ino, current->comm); + if (rc <= 0) return rc; + if (rc > SMACK_UNCONFINED_OBJECT) + rc = 0; smk_bu_mode(mode, acc); - pr_info("Smack Bringup: (%s %s %s) file=(%s %ld %pD) %s\n", + pr_info("Smack %s: (%s %s %s) file=(%s %ld %pD) %s\n", smk_bu_mess[rc], sskp->smk_known, smk_of_inode(inode)->smk_known, acc, inode->i_sb->s_id, inode->i_ino, file, current->comm); diff --git a/security/smack/smackfs.c b/security/smack/smackfs.c index bce4e8f1b267..deb3d3bfbbf3 100644 --- a/security/smack/smackfs.c +++ b/security/smack/smackfs.c @@ -54,6 +54,9 @@ enum smk_inos { SMK_CHANGE_RULE = 19, /* change or add rules (long labels) */ SMK_SYSLOG = 20, /* change syslog label) */ SMK_PTRACE = 21, /* set ptrace rule */ +#ifdef CONFIG_SECURITY_SMACK_BRINGUP + SMK_UNCONFINED = 22, /* define an unconfined label */ +#endif }; /* @@ -95,6 +98,16 @@ int smack_cipso_mapped = SMACK_CIPSO_MAPPED_DEFAULT; */ struct smack_known *smack_onlycap; +#ifdef CONFIG_SECURITY_SMACK_BRINGUP +/* + * Allow one label to be unconfined. This is for + * debugging and application bring-up purposes only. + * It is bad and wrong, but everyone seems to expect + * to have it. + */ +struct smack_known *smack_unconfined; +#endif + /* * If this value is set restrict syslog use to the label specified. * It can be reset via smackfs/syslog @@ -1717,6 +1730,85 @@ static const struct file_operations smk_onlycap_ops = { .llseek = default_llseek, }; +#ifdef CONFIG_SECURITY_SMACK_BRINGUP +/** + * smk_read_unconfined - read() for smackfs/unconfined + * @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_unconfined(struct file *filp, char __user *buf, + size_t cn, loff_t *ppos) +{ + char *smack = ""; + ssize_t rc = -EINVAL; + int asize; + + if (*ppos != 0) + return 0; + + if (smack_unconfined != NULL) + smack = smack_unconfined->smk_known; + + asize = strlen(smack) + 1; + + if (cn >= asize) + rc = simple_read_from_buffer(buf, cn, ppos, smack, asize); + + return rc; +} + +/** + * smk_write_unconfined - write() for smackfs/unconfined + * @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_unconfined(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + char *data; + int rc = count; + + if (!smack_privileged(CAP_MAC_ADMIN)) + return -EPERM; + + data = kzalloc(count + 1, GFP_KERNEL); + if (data == NULL) + return -ENOMEM; + + /* + * Should the null string be passed in unset the unconfined value. + * This seems like something to be careful with as usually + * smk_import only expects to return NULL for errors. It + * is usually the case that a nullstring or "\n" would be + * bad to pass to smk_import but in fact this is useful here. + * + * smk_import will also reject a label beginning with '-', + * so "-confine" will also work. + */ + if (copy_from_user(data, buf, count) != 0) + rc = -EFAULT; + else + smack_unconfined = smk_import_entry(data, count); + + kfree(data); + return rc; +} + +static const struct file_operations smk_unconfined_ops = { + .read = smk_read_unconfined, + .write = smk_write_unconfined, + .llseek = default_llseek, +}; +#endif /* CONFIG_SECURITY_SMACK_BRINGUP */ + /** * smk_read_logging - read() for /smack/logging * @filp: file pointer, not actually used @@ -2384,6 +2476,10 @@ static int smk_fill_super(struct super_block *sb, void *data, int silent) "syslog", &smk_syslog_ops, S_IRUGO|S_IWUSR}, [SMK_PTRACE] = { "ptrace", &smk_ptrace_ops, S_IRUGO|S_IWUSR}, +#ifdef CONFIG_SECURITY_SMACK_BRINGUP + [SMK_UNCONFINED] = { + "unconfined", &smk_unconfined_ops, S_IRUGO|S_IWUSR}, +#endif /* last one */ {""} }; |