diff options
Diffstat (limited to 'security/smack/smackfs.c')
| -rw-r--r-- | security/smack/smackfs.c | 3059 |
1 files changed, 3059 insertions, 0 deletions
diff --git a/security/smack/smackfs.c b/security/smack/smackfs.c new file mode 100644 index 000000000..a9c516362 --- /dev/null +++ b/security/smack/smackfs.c @@ -0,0 +1,3059 @@ +/* + * Copyright (C) 2007 Casey Schaufler <casey@schaufler-ca.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, version 2. + * + * Authors: + * Casey Schaufler <casey@schaufler-ca.com> + * Ahmed S. Darwish <darwish.07@gmail.com> + * + * Special thanks to the authors of selinuxfs. + * + * Karl MacMillan <kmacmillan@tresys.com> + * James Morris <jmorris@redhat.com> + * + */ + +#include <linux/kernel.h> +#include <linux/vmalloc.h> +#include <linux/security.h> +#include <linux/mutex.h> +#include <linux/slab.h> +#include <net/net_namespace.h> +#include <net/cipso_ipv4.h> +#include <linux/seq_file.h> +#include <linux/ctype.h> +#include <linux/audit.h> +#include <linux/magic.h> +#include "smack.h" + +#define BEBITS (sizeof(__be32) * 8) +/* + * smackfs pseudo filesystem. + */ + +enum smk_inos { + SMK_ROOT_INO = 2, + SMK_LOAD = 3, /* load policy */ + SMK_CIPSO = 4, /* load label -> CIPSO mapping */ + SMK_DOI = 5, /* CIPSO DOI */ + SMK_DIRECT = 6, /* CIPSO level indicating direct label */ + SMK_AMBIENT = 7, /* internet ambient label */ + SMK_NET4ADDR = 8, /* single label hosts */ + SMK_ONLYCAP = 9, /* the only "capable" label */ + SMK_LOGGING = 10, /* logging */ + SMK_LOAD_SELF = 11, /* task specific rules */ + SMK_ACCESSES = 12, /* access policy */ + SMK_MAPPED = 13, /* CIPSO level indicating mapped label */ + SMK_LOAD2 = 14, /* load policy with long labels */ + SMK_LOAD_SELF2 = 15, /* load task specific rules with long labels */ + SMK_ACCESS2 = 16, /* make an access check with long labels */ + 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) */ + SMK_PTRACE = 21, /* set ptrace rule */ +#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 */ + SMK_RELABEL_SELF = 24, /* relabel possible without CAP_MAC_ADMIN */ +}; + +/* + * List locks + */ +static DEFINE_MUTEX(smack_master_list_lock); +static DEFINE_MUTEX(smack_cipso_lock); +static DEFINE_MUTEX(smack_ambient_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. + * If it isn't somehow marked, use this. + * It can be reset via smackfs/ambient + */ +struct smack_known *smack_net_ambient; + +/* + * This is the level in a CIPSO header that indicates a + * smack label is contained directly in the category set. + * It can be reset via smackfs/direct + */ +int smack_cipso_direct = SMACK_CIPSO_DIRECT_DEFAULT; + +/* + * This is the level in a CIPSO header that indicates a + * secid is contained directly in the category set. + * It can be reset via smackfs/mapped + */ +int smack_cipso_mapped = SMACK_CIPSO_MAPPED_DEFAULT; + +#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 + */ +struct smack_known *smack_syslog_label; + +/* + * Ptrace current rule + * SMACK_PTRACE_DEFAULT regular smack ptrace rules (/proc based) + * SMACK_PTRACE_EXACT labels must match, but can be overriden with + * CAP_SYS_PTRACE + * SMACK_PTRACE_DRACONIAN lables must match, CAP_SYS_PTRACE has no effect + */ +int smack_ptrace_rule = SMACK_PTRACE_DEFAULT; + +/* + * Certain IP addresses may be designated as single label hosts. + * Packets are sent there unlabeled, but only from tasks that + * can write to the specified label. + */ + +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. + * This master list is just for reading /smack/load and /smack/load2. + */ +struct smack_master_list { + struct list_head list; + struct smack_rule *smk_rule; +}; + +static LIST_HEAD(smack_rule_list); + +struct smack_parsed_rule { + struct smack_known *smk_subject; + struct smack_known *smk_object; + int smk_access1; + int smk_access2; +}; + +static int smk_cipso_doi_value = SMACK_CIPSO_DOI_DEFAULT; + +/* + * Values for parsing cipso rules + * SMK_DIGITLEN: Length of a digit field in a rule. + * SMK_CIPSOMIN: Minimum possible cipso rule length. + * SMK_CIPSOMAX: Maximum possible cipso rule length. + */ +#define SMK_DIGITLEN 4 +#define SMK_CIPSOMIN (SMK_LABELLEN + 2 * SMK_DIGITLEN) +#define SMK_CIPSOMAX (SMK_CIPSOMIN + SMACK_CIPSO_MAXCATNUM * SMK_DIGITLEN) + +/* + * Values for parsing MAC rules + * SMK_ACCESS: Maximum possible combination of access permissions + * SMK_ACCESSLEN: Maximum length for a rule access field + * SMK_LOADLEN: Smack rule length + */ +#define SMK_OACCESS "rwxa" +#define SMK_ACCESS "rwxatl" +#define SMK_OACCESSLEN (sizeof(SMK_OACCESS) - 1) +#define SMK_ACCESSLEN (sizeof(SMK_ACCESS) - 1) +#define SMK_OLOADLEN (SMK_LABELLEN + SMK_LABELLEN + SMK_OACCESSLEN) +#define SMK_LOADLEN (SMK_LABELLEN + SMK_LABELLEN + SMK_ACCESSLEN) + +/* + * Stricly for CIPSO level manipulation. + * Set the category bit number in a smack label sized buffer. + */ +static inline void smack_catset_bit(unsigned int cat, char *catsetp) +{ + if (cat == 0 || cat > (SMK_CIPSOLEN * 8)) + return; + + catsetp[(cat - 1) / 8] |= 0x80 >> ((cat - 1) % 8); +} + +/** + * smk_netlabel_audit_set - fill a netlbl_audit struct + * @nap: structure to fill + */ +static void smk_netlabel_audit_set(struct netlbl_audit *nap) +{ + struct smack_known *skp = smk_of_current(); + + nap->loginuid = audit_get_loginuid(current); + nap->sessionid = audit_get_sessionid(current); + nap->secid = skp->smk_secid; +} + +/* + * Value for parsing single label host rules + * "1.2.3.4 X" + */ +#define SMK_NETLBLADDRMIN 9 + +/** + * smk_set_access - add a rule to the rule list or replace an old rule + * @srp: the rule to add or replace + * @rule_list: the list of rules + * @rule_lock: the rule list lock + * @global: if non-zero, indicates a global rule + * + * Looks through the current subject/object/access list for + * the subject/object pair and replaces the access that was + * there. If the pair isn't found add it with the specified + * access. + * + * Returns 0 if nothing goes wrong or -ENOMEM if it fails + * during the allocation of the new pair to add. + */ +static int smk_set_access(struct smack_parsed_rule *srp, + struct list_head *rule_list, + struct mutex *rule_lock, int global) +{ + struct smack_rule *sp; + struct smack_master_list *smlp; + int found = 0; + int rc = 0; + + mutex_lock(rule_lock); + + /* + * Because the object label is less likely to match + * than the subject label check it first + */ + list_for_each_entry_rcu(sp, rule_list, list) { + if (sp->smk_object == srp->smk_object && + sp->smk_subject == srp->smk_subject) { + found = 1; + sp->smk_access |= srp->smk_access1; + sp->smk_access &= ~srp->smk_access2; + break; + } + } + + if (found == 0) { + sp = kzalloc(sizeof(*sp), GFP_KERNEL); + if (sp == NULL) { + rc = -ENOMEM; + goto out; + } + + sp->smk_subject = srp->smk_subject; + sp->smk_object = srp->smk_object; + sp->smk_access = srp->smk_access1 & ~srp->smk_access2; + + list_add_rcu(&sp->list, rule_list); + /* + * If this is a global as opposed to self and a new rule + * it needs to get added for reporting. + */ + if (global) { + mutex_unlock(rule_lock); + smlp = kzalloc(sizeof(*smlp), GFP_KERNEL); + if (smlp != NULL) { + smlp->smk_rule = sp; + mutex_lock(&smack_master_list_lock); + list_add_rcu(&smlp->list, &smack_rule_list); + mutex_unlock(&smack_master_list_lock); + } else + rc = -ENOMEM; + return rc; + } + } + +out: + mutex_unlock(rule_lock); + return rc; +} + +/** + * smk_perm_from_str - parse smack accesses from a text string + * @string: a text string that contains a Smack accesses code + * + * Returns an integer with respective bits set for specified accesses. + */ +static int smk_perm_from_str(const char *string) +{ + int perm = 0; + const char *cp; + + for (cp = string; ; cp++) + switch (*cp) { + case '-': + break; + case 'r': + case 'R': + perm |= MAY_READ; + break; + case 'w': + case 'W': + perm |= MAY_WRITE; + break; + case 'x': + case 'X': + perm |= MAY_EXEC; + break; + case 'a': + case 'A': + perm |= MAY_APPEND; + break; + case 't': + case 'T': + perm |= MAY_TRANSMUTE; + break; + case 'l': + case 'L': + perm |= MAY_LOCK; + break; + case 'b': + case 'B': + perm |= MAY_BRINGUP; + break; + default: + return perm; + } +} + +/** + * smk_fill_rule - Fill Smack rule from strings + * @subject: subject label string + * @object: object label string + * @access1: access string + * @access2: string with permissions to be removed + * @rule: Smack rule + * @import: if non-zero, import labels + * @len: label length limit + * + * Returns 0 on success, appropriate error code on failure. + */ +static int smk_fill_rule(const char *subject, const char *object, + const char *access1, const char *access2, + struct smack_parsed_rule *rule, int import, + int len) +{ + const char *cp; + struct smack_known *skp; + + if (import) { + rule->smk_subject = smk_import_entry(subject, len); + if (IS_ERR(rule->smk_subject)) + return PTR_ERR(rule->smk_subject); + + rule->smk_object = smk_import_entry(object, len); + if (IS_ERR(rule->smk_object)) + return PTR_ERR(rule->smk_object); + } else { + cp = smk_parse_smack(subject, len); + if (IS_ERR(cp)) + return PTR_ERR(cp); + skp = smk_find_entry(cp); + kfree(cp); + if (skp == NULL) + return -ENOENT; + rule->smk_subject = skp; + + cp = smk_parse_smack(object, len); + if (IS_ERR(cp)) + return PTR_ERR(cp); + skp = smk_find_entry(cp); + kfree(cp); + if (skp == NULL) + return -ENOENT; + rule->smk_object = skp; + } + + rule->smk_access1 = smk_perm_from_str(access1); + if (access2) + rule->smk_access2 = smk_perm_from_str(access2); + else + rule->smk_access2 = ~rule->smk_access1; + + return 0; +} + +/** + * smk_parse_rule - parse Smack rule from load string + * @data: string to be parsed whose size is SMK_LOADLEN + * @rule: Smack rule + * @import: if non-zero, import labels + * + * Returns 0 on success, -1 on errors. + */ +static int smk_parse_rule(const char *data, struct smack_parsed_rule *rule, + int import) +{ + int rc; + + rc = smk_fill_rule(data, data + SMK_LABELLEN, + data + SMK_LABELLEN + SMK_LABELLEN, NULL, rule, + import, SMK_LABELLEN); + return rc; +} + +/** + * smk_parse_long_rule - parse Smack rule from rule string + * @data: string to be parsed, null terminated + * @rule: Will be filled with Smack parsed rule + * @import: if non-zero, import labels + * @tokens: numer of substrings expected in data + * + * Returns number of processed bytes on success, -ERRNO on failure. + */ +static ssize_t smk_parse_long_rule(char *data, struct smack_parsed_rule *rule, + int import, int tokens) +{ + ssize_t cnt = 0; + char *tok[4]; + int rc; + int i; + + /* + * Parsing the rule in-place, filling all white-spaces with '\0' + */ + for (i = 0; i < tokens; ++i) { + while (isspace(data[cnt])) + data[cnt++] = '\0'; + + if (data[cnt] == '\0') + /* Unexpected end of data */ + return -EINVAL; + + tok[i] = data + cnt; + + while (data[cnt] && !isspace(data[cnt])) + ++cnt; + } + while (isspace(data[cnt])) + data[cnt++] = '\0'; + + while (i < 4) + tok[i++] = NULL; + + 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 */ +#define SMK_LONG_FMT 1 /* Variable long label format */ +#define SMK_CHANGE_FMT 2 /* Rule modification format */ +/** + * smk_write_rules_list - write() for any /smack rule file + * @file: file pointer, not actually used + * @buf: where to get the data from + * @count: bytes sent + * @ppos: where to start - must be 0 + * @rule_list: the list of rules to write to + * @rule_lock: lock for the rule list + * @format: /smack/load or /smack/load2 or /smack/change-rule format. + * + * Get one smack access rule from above. + * The format for SMK_LONG_FMT is: + * "subject<whitespace>object<whitespace>access[<whitespace>...]" + * The format for SMK_FIXED24_FMT is exactly: + * "subject object rwxat" + * The format for SMK_CHANGE_FMT is: + * "subject<whitespace>object<whitespace> + * acc_enable<whitespace>acc_disable[<whitespace>...]" + */ +static ssize_t smk_write_rules_list(struct file *file, const char __user *buf, + size_t count, loff_t *ppos, + struct list_head *rule_list, + struct mutex *rule_lock, int format) +{ + struct smack_parsed_rule rule; + char *data; + int rc; + int trunc = 0; + int tokens; + ssize_t cnt = 0; + + /* + * No partial writes. + * Enough data must be present. + */ + if (*ppos != 0) + return -EINVAL; + + if (format == SMK_FIXED24_FMT) { + /* + * Minor hack for backward compatibility + */ + if (count < SMK_OLOADLEN || count > SMK_LOADLEN) + return -EINVAL; + } else { + if (count >= PAGE_SIZE) { + count = PAGE_SIZE - 1; + trunc = 1; + } + } + + data = memdup_user_nul(buf, count); + if (IS_ERR(data)) + return PTR_ERR(data); + + /* + * In case of parsing only part of user buf, + * avoid having partial rule at the data buffer + */ + if (trunc) { + while (count > 0 && (data[count - 1] != '\n')) + --count; + if (count == 0) { + rc = -EINVAL; + goto out; + } + } + + data[count] = '\0'; + tokens = (format == SMK_CHANGE_FMT ? 4 : 3); + while (cnt < count) { + if (format == SMK_FIXED24_FMT) { + rc = smk_parse_rule(data, &rule, 1); + if (rc < 0) + goto out; + cnt = count; + } else { + rc = smk_parse_long_rule(data + cnt, &rule, 1, tokens); + if (rc < 0) + goto out; + if (rc == 0) { + rc = -EINVAL; + goto out; + } + cnt += rc; + } + + if (rule_list == NULL) + rc = smk_set_access(&rule, &rule.smk_subject->smk_rules, + &rule.smk_subject->smk_rules_lock, 1); + else + rc = smk_set_access(&rule, rule_list, rule_lock, 0); + + if (rc) + goto out; + } + + rc = cnt; +out: + kfree(data); + return rc; +} + +/* + * Core logic for smackfs seq list operations. + */ + +static void *smk_seq_start(struct seq_file *s, loff_t *pos, + struct list_head *head) +{ + struct list_head *list; + int i = *pos; + + rcu_read_lock(); + for (list = rcu_dereference(list_next_rcu(head)); + list != head; + list = rcu_dereference(list_next_rcu(list))) { + if (i-- == 0) + return list; + } + + return NULL; +} + +static void *smk_seq_next(struct seq_file *s, void *v, loff_t *pos, + struct list_head *head) +{ + struct list_head *list = v; + + ++*pos; + list = rcu_dereference(list_next_rcu(list)); + + return (list == head) ? NULL : list; +} + +static void smk_seq_stop(struct seq_file *s, void *v) +{ + rcu_read_unlock(); +} + +static void smk_rule_show(struct seq_file *s, struct smack_rule *srp, int max) +{ + /* + * Don't show any rules with label names too long for + * interface file (/smack/load or /smack/load2) + * because you should expect to be able to write + * anything you read back. + */ + if (strlen(srp->smk_subject->smk_known) >= max || + strlen(srp->smk_object->smk_known) >= max) + return; + + if (srp->smk_access == 0) + return; + + seq_printf(s, "%s %s", + srp->smk_subject->smk_known, + srp->smk_object->smk_known); + + seq_putc(s, ' '); + + if (srp->smk_access & MAY_READ) + seq_putc(s, 'r'); + if (srp->smk_access & MAY_WRITE) + seq_putc(s, 'w'); + if (srp->smk_access & MAY_EXEC) + seq_putc(s, 'x'); + if (srp->smk_access & MAY_APPEND) + seq_putc(s, 'a'); + if (srp->smk_access & MAY_TRANSMUTE) + seq_putc(s, 't'); + if (srp->smk_access & MAY_LOCK) + seq_putc(s, 'l'); + if (srp->smk_access & MAY_BRINGUP) + seq_putc(s, 'b'); + + seq_putc(s, '\n'); +} + +/* + * Seq_file read operations for /smack/load + */ + +static void *load2_seq_start(struct seq_file *s, loff_t *pos) +{ + return smk_seq_start(s, pos, &smack_rule_list); +} + +static void *load2_seq_next(struct seq_file *s, void *v, loff_t *pos) +{ + return smk_seq_next(s, v, pos, &smack_rule_list); +} + +static int load_seq_show(struct seq_file *s, void *v) +{ + struct list_head *list = v; + struct smack_master_list *smlp = + list_entry_rcu(list, struct smack_master_list, list); + + smk_rule_show(s, smlp->smk_rule, SMK_LABELLEN); + + return 0; +} + +static const struct seq_operations load_seq_ops = { + .start = load2_seq_start, + .next = load2_seq_next, + .show = load_seq_show, + .stop = smk_seq_stop, +}; + +/** + * smk_open_load - open() for /smack/load + * @inode: inode structure representing file + * @file: "load" file pointer + * + * For reading, use load_seq_* seq_file reading operations. + */ +static int smk_open_load(struct inode *inode, struct file *file) +{ + return seq_open(file, &load_seq_ops); +} + +/** + * smk_write_load - write() for /smack/load + * @file: file pointer, not actually used + * @buf: where to get the data from + * @count: bytes sent + * @ppos: where to start - must be 0 + * + */ +static ssize_t smk_write_load(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + /* + * Must have privilege. + * No partial writes. + * Enough data must be present. + */ + if (!smack_privileged(CAP_MAC_ADMIN)) + return -EPERM; + + return smk_write_rules_list(file, buf, count, ppos, NULL, NULL, + SMK_FIXED24_FMT); +} + +static const struct file_operations smk_load_ops = { + .open = smk_open_load, + .read = seq_read, + .llseek = seq_lseek, + .write = smk_write_load, + .release = seq_release, +}; + +/** + * smk_cipso_doi - initialize the CIPSO domain + */ +static void smk_cipso_doi(void) +{ + int rc; + struct cipso_v4_doi *doip; + struct netlbl_audit nai; + + smk_netlabel_audit_set(&nai); + + rc = netlbl_cfg_map_del(NULL, PF_INET, NULL, NULL, &nai); + if (rc != 0) + printk(KERN_WARNING "%s:%d remove rc = %d\n", + __func__, __LINE__, rc); + + doip = kmalloc(sizeof(struct cipso_v4_doi), GFP_KERNEL | __GFP_NOFAIL); + doip->map.std = NULL; + doip->doi = smk_cipso_doi_value; + doip->type = CIPSO_V4_MAP_PASS; + doip->tags[0] = CIPSO_V4_TAG_RBITMAP; + for (rc = 1; rc < CIPSO_V4_TAG_MAXCNT; rc++) + doip->tags[rc] = CIPSO_V4_TAG_INVALID; + + rc = netlbl_cfg_cipsov4_add(doip, &nai); + if (rc != 0) { + printk(KERN_WARNING "%s:%d cipso add rc = %d\n", + __func__, __LINE__, rc); + kfree(doip); + return; + } + rc = netlbl_cfg_cipsov4_map_add(doip->doi, NULL, NULL, NULL, &nai); + if (rc != 0) { + printk(KERN_WARNING "%s:%d map add rc = %d\n", + __func__, __LINE__, rc); + netlbl_cfg_cipsov4_del(doip->doi, &nai); + return; + } +} + +/** + * smk_unlbl_ambient - initialize the unlabeled domain + * @oldambient: previous domain string + */ +static void smk_unlbl_ambient(char *oldambient) +{ + int rc; + struct netlbl_audit nai; + + smk_netlabel_audit_set(&nai); + + if (oldambient != NULL) { + rc = netlbl_cfg_map_del(oldambient, PF_INET, NULL, NULL, &nai); + if (rc != 0) + printk(KERN_WARNING "%s:%d remove rc = %d\n", + __func__, __LINE__, rc); + } + if (smack_net_ambient == NULL) + smack_net_ambient = &smack_known_floor; + + rc = netlbl_cfg_unlbl_map_add(smack_net_ambient->smk_known, PF_INET, + NULL, NULL, &nai); + if (rc != 0) + printk(KERN_WARNING "%s:%d add rc = %d\n", + __func__, __LINE__, rc); +} + +/* + * Seq_file read operations for /smack/cipso + */ + +static void *cipso_seq_start(struct seq_file *s, loff_t *pos) +{ + return smk_seq_start(s, pos, &smack_known_list); +} + +static void *cipso_seq_next(struct seq_file *s, void *v, loff_t *pos) +{ + return smk_seq_next(s, v, pos, &smack_known_list); +} + +/* + * Print cipso labels in format: + * label level[/cat[,cat]] + */ +static int cipso_seq_show(struct seq_file *s, void *v) +{ + struct list_head *list = v; + struct smack_known *skp = + list_entry_rcu(list, struct smack_known, list); + struct netlbl_lsm_catmap *cmp = skp->smk_netlabel.attr.mls.cat; + char sep = '/'; + int i; + + /* + * Don't show a label that could not have been set using + * /smack/cipso. This is in support of the notion that + * anything read from /smack/cipso ought to be writeable + * to /smack/cipso. + * + * /smack/cipso2 should be used instead. + */ + if (strlen(skp->smk_known) >= SMK_LABELLEN) + return 0; + + seq_printf(s, "%s %3d", skp->smk_known, skp->smk_netlabel.attr.mls.lvl); + + for (i = netlbl_catmap_walk(cmp, 0); i >= 0; + i = netlbl_catmap_walk(cmp, i + 1)) { + seq_printf(s, "%c%d", sep, i); + sep = ','; + } + + seq_putc(s, '\n'); + + return 0; +} + +static const struct seq_operations cipso_seq_ops = { + .start = cipso_seq_start, + .next = cipso_seq_next, + .show = cipso_seq_show, + .stop = smk_seq_stop, +}; + +/** + * smk_open_cipso - open() for /smack/cipso + * @inode: inode structure representing file + * @file: "cipso" file pointer + * + * Connect our cipso_seq_* operations with /smack/cipso + * file_operations + */ +static int smk_open_cipso(struct inode *inode, struct file *file) +{ + return seq_open(file, &cipso_seq_ops); +} + +/** + * smk_set_cipso - do the work for write() for cipso and cipso2 + * @file: file pointer, not actually used + * @buf: where to get the data from + * @count: bytes sent + * @ppos: where to start + * @format: /smack/cipso or /smack/cipso2 + * + * Accepts only one cipso rule per write call. + * Returns number of bytes written or error code, as appropriate + */ +static ssize_t smk_set_cipso(struct file *file, const char __user *buf, + size_t count, loff_t *ppos, int format) +{ + struct netlbl_lsm_catmap *old_cat; + struct smack_known *skp; + struct netlbl_lsm_secattr ncats; + char mapcatset[SMK_CIPSOLEN]; + int maplevel; + unsigned int cat; + int catlen; + ssize_t rc = -EINVAL; + char *data = NULL; + char *rule; + int ret; + int i; + + /* + * Must have privilege. + * No partial writes. + * Enough data must be present. + */ + if (!smack_privileged(CAP_MAC_ADMIN)) + return -EPERM; + if (*ppos != 0) + return -EINVAL; + if (format == SMK_FIXED24_FMT && + (count < SMK_CIPSOMIN || count > SMK_CIPSOMAX)) + return -EINVAL; + if (count > PAGE_SIZE) + return -EINVAL; + + data = memdup_user_nul(buf, count); + if (IS_ERR(data)) + return PTR_ERR(data); + + rule = data; + /* + * Only allow one writer at a time. Writes should be + * quite rare and small in any case. + */ + mutex_lock(&smack_cipso_lock); + + skp = smk_import_entry(rule, 0); + if (IS_ERR(skp)) { + rc = PTR_ERR(skp); + goto out; + } + + if (format == SMK_FIXED24_FMT) + rule += SMK_LABELLEN; + else + rule += strlen(skp->smk_known) + 1; + + if (rule > data + count) { + rc = -EOVERFLOW; + goto out; + } + + ret = sscanf(rule, "%d", &maplevel); + if (ret != 1 || maplevel < 0 || maplevel > SMACK_CIPSO_MAXLEVEL) + goto out; + + rule += SMK_DIGITLEN; + if (rule > data + count) { + rc = -EOVERFLOW; + goto out; + } + + ret = sscanf(rule, "%d", &catlen); + if (ret != 1 || catlen > SMACK_CIPSO_MAXCATNUM) + goto out; + + if (format == SMK_FIXED24_FMT && + count != (SMK_CIPSOMIN + catlen * SMK_DIGITLEN)) + goto out; + + memset(mapcatset, 0, sizeof(mapcatset)); + + for (i = 0; i < catlen; i++) { + rule += SMK_DIGITLEN; + if (rule > data + count) { + rc = -EOVERFLOW; + goto out; + } + ret = sscanf(rule, "%u", &cat); + if (ret != 1 || cat > SMACK_CIPSO_MAXCATNUM) + goto out; + + smack_catset_bit(cat, mapcatset); + } + + rc = smk_netlbl_mls(maplevel, mapcatset, &ncats, SMK_CIPSOLEN); + if (rc >= 0) { + old_cat = skp->smk_netlabel.attr.mls.cat; + skp->smk_netlabel.attr.mls.cat = ncats.attr.mls.cat; + skp->smk_netlabel.attr.mls.lvl = ncats.attr.mls.lvl; + synchronize_rcu(); + netlbl_catmap_free(old_cat); + rc = count; + } + +out: + mutex_unlock(&smack_cipso_lock); + kfree(data); + return rc; +} + +/** + * smk_write_cipso - write() for /smack/cipso + * @file: file pointer, not actually used + * @buf: where to get the data from + * @count: bytes sent + * @ppos: where to start + * + * Accepts only one cipso rule per write call. + * Returns number of bytes written or error code, as appropriate + */ +static ssize_t smk_write_cipso(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + return smk_set_cipso(file, buf, count, ppos, SMK_FIXED24_FMT); +} + +static const struct file_operations smk_cipso_ops = { + .open = smk_open_cipso, + .read = seq_read, + .llseek = seq_lseek, + .write = smk_write_cipso, + .release = seq_release, +}; + +/* + * Seq_file read operations for /smack/cipso2 + */ + +/* + * Print cipso labels in format: + * label level[/cat[,cat]] + */ +static int cipso2_seq_show(struct seq_file *s, void *v) +{ + struct list_head *list = v; + struct smack_known *skp = + list_entry_rcu(list, struct smack_known, list); + struct netlbl_lsm_catmap *cmp = skp->smk_netlabel.attr.mls.cat; + char sep = '/'; + int i; + + seq_printf(s, "%s %3d", skp->smk_known, skp->smk_netlabel.attr.mls.lvl); + + for (i = netlbl_catmap_walk(cmp, 0); i >= 0; + i = netlbl_catmap_walk(cmp, i + 1)) { + seq_printf(s, "%c%d", sep, i); + sep = ','; + } + + seq_putc(s, '\n'); + + return 0; +} + +static const struct seq_operations cipso2_seq_ops = { + .start = cipso_seq_start, + .next = cipso_seq_next, + .show = cipso2_seq_show, + .stop = smk_seq_stop, +}; + +/** + * smk_open_cipso2 - open() for /smack/cipso2 + * @inode: inode structure representing file + * @file: "cipso2" file pointer + * + * Connect our cipso_seq_* operations with /smack/cipso2 + * file_operations + */ +static int smk_open_cipso2(struct inode *inode, struct file *file) +{ + return seq_open(file, &cipso2_seq_ops); +} + +/** + * smk_write_cipso2 - write() for /smack/cipso2 + * @file: file pointer, not actually used + * @buf: where to get the data from + * @count: bytes sent + * @ppos: where to start + * + * Accepts only one cipso rule per write call. + * Returns number of bytes written or error code, as appropriate + */ +static ssize_t smk_write_cipso2(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + return smk_set_cipso(file, buf, count, ppos, SMK_LONG_FMT); +} + +static const struct file_operations smk_cipso2_ops = { + .open = smk_open_cipso2, + .read = seq_read, + .llseek = seq_lseek, + .write = smk_write_cipso2, + .release = seq_release, +}; + +/* + * Seq_file read operations for /smack/netlabel + */ + +static void *net4addr_seq_start(struct seq_file *s, loff_t *pos) +{ + return smk_seq_start(s, pos, &smk_net4addr_list); +} + +static void *net4addr_seq_next(struct seq_file *s, void *v, loff_t *pos) +{ + return smk_seq_next(s, v, pos, &smk_net4addr_list); +} + +/* + * Print host/label pairs + */ +static int net4addr_seq_show(struct seq_file *s, void *v) +{ + struct list_head *list = v; + struct smk_net4addr *skp = + list_entry_rcu(list, struct smk_net4addr, list); + char *kp = SMACK_CIPSO_OPTION; + + 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 net4addr_seq_ops = { + .start = net4addr_seq_start, + .next = net4addr_seq_next, + .show = net4addr_seq_show, + .stop = smk_seq_stop, +}; + +/** + * smk_open_net4addr - open() for /smack/netlabel + * @inode: inode structure representing file + * @file: "netlabel" file pointer + * + * Connect our net4addr_seq_* operations with /smack/netlabel + * file_operations + */ +static int smk_open_net4addr(struct inode *inode, struct file *file) +{ + return seq_open(file, &net4addr_seq_ops); +} + +/** + * smk_net4addr_insert + * @new : netlabel to insert + * + * This helper insert netlabel in the smack_net4addrs list + * sorted by netmask length (longest to smallest) + * locked by &smk_net4addr_lock in smk_write_net4addr + * + */ +static void smk_net4addr_insert(struct smk_net4addr *new) +{ + struct smk_net4addr *m; + struct smk_net4addr *m_next; + + if (list_empty(&smk_net4addr_list)) { + list_add_rcu(&new->list, &smk_net4addr_list); + return; + } + + m = list_entry_rcu(smk_net4addr_list.next, + struct smk_net4addr, list); + + /* the comparison '>' is a bit hacky, but works */ + if (new->smk_masks > m->smk_masks) { + list_add_rcu(&new->list, &smk_net4addr_list); + return; + } + + 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_net4addr, list); + if (new->smk_masks > m_next->smk_masks) { + list_add_rcu(&new->list, &m->list); + return; + } + } +} + + +/** + * 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 net4addr per write call. + * Returns number of bytes written or error code, as appropriate + */ +static ssize_t smk_write_net4addr(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct smk_net4addr *snp; + struct sockaddr_in newname; + char *smack; + 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; + u32 temp_mask; + + /* + * Must have privilege. + * No partial writes. + * Enough data must be present. + * "<addr/mask, as a.b.c.d/e><space><label>" + * "<addr, as a.b.c.d><space><label>" + */ + if (!smack_privileged(CAP_MAC_ADMIN)) + return -EPERM; + if (*ppos != 0) + return -EINVAL; + if (count < SMK_NETLBLADDRMIN || count > PAGE_SIZE - 1) + return -EINVAL; + + data = memdup_user_nul(buf, count); + if (IS_ERR(data)) + return PTR_ERR(data); + + smack = kzalloc(count + 1, GFP_KERNEL); + if (smack == NULL) { + rc = -ENOMEM; + goto free_data_out; + } + + rc = sscanf(data, "%hhd.%hhd.%hhd.%hhd/%u %s", + &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); + if (rc != 5) { + rc = -EINVAL; + goto free_out; + } + m = BEBITS; + masks = 32; + } + if (masks > BEBITS) { + rc = -EINVAL; + goto free_out; + } + + /* + * If smack begins with '-', it is an option, don't import it + */ + if (smack[0] != '-') { + skp = smk_import_entry(smack, 0); + if (IS_ERR(skp)) { + rc = PTR_ERR(skp); + goto free_out; + } + } else { + /* + * Only the -CIPSO option is supported for IPv4 + */ + if (strcmp(smack, SMACK_CIPSO_OPTION) != 0) { + rc = -EINVAL; + goto free_out; + } + } + + for (m = masks, temp_mask = 0; m > 0; m--) { + temp_mask |= mask_bits; + mask_bits >>= 1; + } + mask.s_addr = cpu_to_be32(temp_mask); + + newname.sin_addr.s_addr &= mask.s_addr; + /* + * Only allow one writer at a time. Writes should be + * quite rare and small in any case. + */ + 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_net4addr_list, list) { + if (snp->smk_host.s_addr == nsa && snp->smk_masks == masks) { + found = 1; + break; + } + } + smk_netlabel_audit_set(&audit_info); + + if (found == 0) { + snp = kzalloc(sizeof(*snp), GFP_KERNEL); + if (snp == NULL) + rc = -ENOMEM; + else { + rc = 0; + snp->smk_host.s_addr = newname.sin_addr.s_addr; + snp->smk_mask.s_addr = mask.s_addr; + snp->smk_label = skp; + snp->smk_masks = masks; + smk_net4addr_insert(snp); + } + } else { + /* + * 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, &snp->smk_mask, + PF_INET, &audit_info); + else + rc = 0; + snp->smk_label = skp; + } + + /* + * Now tell netlabel about the single label nature of + * this host so that incoming packets get labeled. + * but only if we didn't get the special CIPSO option + */ + if (rc == 0 && skp != NULL) + rc = netlbl_cfg_unlbl_static_add(&init_net, NULL, + &snp->smk_host, &snp->smk_mask, PF_INET, + snp->smk_label->smk_secid, &audit_info); + + if (rc == 0) + rc = count; + + mutex_unlock(&smk_net4addr_lock); + +free_out: + kfree(smack); +free_data_out: + kfree(data); + + return rc; +} + +static const struct file_operations smk_net4addr_ops = { + .open = smk_open_net4addr, + .read = seq_read, + .llseek = seq_lseek, + .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 || count > PAGE_SIZE - 1) + return -EINVAL; + + data = memdup_user_nul(buf, count); + if (IS_ERR(data)) + return PTR_ERR(data); + + smack = kzalloc(count + 1, GFP_KERNEL); + if (smack == NULL) { + rc = -ENOMEM; + goto free_data_out; + } + + 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 (IS_ERR(skp)) { + rc = PTR_ERR(skp); + 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 + * @buf: where to put the result + * @count: maximum to send along + * @ppos: where to start + * + * Returns number of bytes read or error code, as appropriate + */ +static ssize_t smk_read_doi(struct file *filp, char __user *buf, + size_t count, loff_t *ppos) +{ + char temp[80]; + ssize_t rc; + + if (*ppos != 0) + return 0; + + sprintf(temp, "%d", smk_cipso_doi_value); + rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp)); + + return rc; +} + +/** + * smk_write_doi - write() for /smack/doi + * @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_doi(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + char temp[80]; + int i; + + if (!smack_privileged(CAP_MAC_ADMIN)) + return -EPERM; + + if (count >= sizeof(temp) || count == 0) + return -EINVAL; + + if (copy_from_user(temp, buf, count) != 0) + return -EFAULT; + + temp[count] = '\0'; + + if (sscanf(temp, "%d", &i) != 1) + return -EINVAL; + + smk_cipso_doi_value = i; + + smk_cipso_doi(); + + return count; +} + +static const struct file_operations smk_doi_ops = { + .read = smk_read_doi, + .write = smk_write_doi, + .llseek = default_llseek, +}; + +/** + * smk_read_direct - read() for /smack/direct + * @filp: file pointer, not actually used + * @buf: where to put the result + * @count: maximum to send along + * @ppos: where to start + * + * Returns number of bytes read or error code, as appropriate + */ +static ssize_t smk_read_direct(struct file *filp, char __user *buf, + size_t count, loff_t *ppos) +{ + char temp[80]; + ssize_t rc; + + if (*ppos != 0) + return 0; + + sprintf(temp, "%d", smack_cipso_direct); + rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp)); + + return rc; +} + +/** + * smk_write_direct - write() for /smack/direct + * @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_direct(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct smack_known *skp; + char temp[80]; + int i; + + if (!smack_privileged(CAP_MAC_ADMIN)) + return -EPERM; + + if (count >= sizeof(temp) || count == 0) + return -EINVAL; + + if (copy_from_user(temp, buf, count) != 0) + return -EFAULT; + + temp[count] = '\0'; + + if (sscanf(temp, "%d", &i) != 1) + return -EINVAL; + + /* + * Don't do anything if the value hasn't actually changed. + * If it is changing reset the level on entries that were + * set up to be direct when they were created. + */ + if (smack_cipso_direct != i) { + mutex_lock(&smack_known_lock); + list_for_each_entry_rcu(skp, &smack_known_list, list) + if (skp->smk_netlabel.attr.mls.lvl == + smack_cipso_direct) + skp->smk_netlabel.attr.mls.lvl = i; + smack_cipso_direct = i; + mutex_unlock(&smack_known_lock); + } + + return count; +} + +static const struct file_operations smk_direct_ops = { + .read = smk_read_direct, + .write = smk_write_direct, + .llseek = default_llseek, +}; + +/** + * smk_read_mapped - read() for /smack/mapped + * @filp: file pointer, not actually used + * @buf: where to put the result + * @count: maximum to send along + * @ppos: where to start + * + * Returns number of bytes read or error code, as appropriate + */ +static ssize_t smk_read_mapped(struct file *filp, char __user *buf, + size_t count, loff_t *ppos) +{ + char temp[80]; + ssize_t rc; + + if (*ppos != 0) + return 0; + + sprintf(temp, "%d", smack_cipso_mapped); + rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp)); + + return rc; +} + +/** + * smk_write_mapped - write() for /smack/mapped + * @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_mapped(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct smack_known *skp; + char temp[80]; + int i; + + if (!smack_privileged(CAP_MAC_ADMIN)) + return -EPERM; + + if (count >= sizeof(temp) || count == 0) + return -EINVAL; + + if (copy_from_user(temp, buf, count) != 0) + return -EFAULT; + + temp[count] = '\0'; + + if (sscanf(temp, "%d", &i) != 1) + return -EINVAL; + + /* + * Don't do anything if the value hasn't actually changed. + * If it is changing reset the level on entries that were + * set up to be mapped when they were created. + */ + if (smack_cipso_mapped != i) { + mutex_lock(&smack_known_lock); + list_for_each_entry_rcu(skp, &smack_known_list, list) + if (skp->smk_netlabel.attr.mls.lvl == + smack_cipso_mapped) + skp->smk_netlabel.attr.mls.lvl = i; + smack_cipso_mapped = i; + mutex_unlock(&smack_known_lock); + } + + return count; +} + +static const struct file_operations smk_mapped_ops = { + .read = smk_read_mapped, + .write = smk_write_mapped, + .llseek = default_llseek, +}; + +/** + * smk_read_ambient - read() for /smack/ambient + * @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_ambient(struct file *filp, char __user *buf, + size_t cn, loff_t *ppos) +{ + ssize_t rc; + int asize; + + if (*ppos != 0) + return 0; + /* + * Being careful to avoid a problem in the case where + * smack_net_ambient gets changed in midstream. + */ + mutex_lock(&smack_ambient_lock); + + asize = strlen(smack_net_ambient->smk_known) + 1; + + if (cn >= asize) + rc = simple_read_from_buffer(buf, cn, ppos, + smack_net_ambient->smk_known, + asize); + else + rc = -EINVAL; + + mutex_unlock(&smack_ambient_lock); + + return rc; +} + +/** + * smk_write_ambient - write() for /smack/ambient + * @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_ambient(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct smack_known *skp; + char *oldambient; + char *data; + int rc = count; + + if (!smack_privileged(CAP_MAC_ADMIN)) + return -EPERM; + + /* Enough data must be present */ + if (count == 0 || count > PAGE_SIZE) + return -EINVAL; + + data = memdup_user_nul(buf, count); + if (IS_ERR(data)) + return PTR_ERR(data); + + skp = smk_import_entry(data, count); + if (IS_ERR(skp)) { + rc = PTR_ERR(skp); + goto out; + } + + mutex_lock(&smack_ambient_lock); + + oldambient = smack_net_ambient->smk_known; + smack_net_ambient = skp; + smk_unlbl_ambient(oldambient); + + mutex_unlock(&smack_ambient_lock); + +out: + kfree(data); + return rc; +} + +static const struct file_operations smk_ambient_ops = { + .read = smk_read_ambient, + .write = smk_write_ambient, + .llseek = default_llseek, +}; + +/* + * Seq_file operations for /smack/onlycap + */ +static void *onlycap_seq_start(struct seq_file *s, loff_t *pos) +{ + return smk_seq_start(s, pos, &smack_onlycap_list); +} + +static void *onlycap_seq_next(struct seq_file *s, void *v, loff_t *pos) +{ + return smk_seq_next(s, v, pos, &smack_onlycap_list); +} + +static int onlycap_seq_show(struct seq_file *s, void *v) +{ + struct list_head *list = v; + struct smack_known_list_elem *sklep = + list_entry_rcu(list, struct smack_known_list_elem, list); + + seq_puts(s, sklep->smk_label->smk_known); + seq_putc(s, ' '); + + return 0; +} + +static const struct seq_operations onlycap_seq_ops = { + .start = onlycap_seq_start, + .next = onlycap_seq_next, + .show = onlycap_seq_show, + .stop = smk_seq_stop, +}; + +static int smk_open_onlycap(struct inode *inode, struct file *file) +{ + return seq_open(file, &onlycap_seq_ops); +} + +/** + * smk_list_swap_rcu - swap public list with a private one in RCU-safe way + * The caller must hold appropriate mutex to prevent concurrent modifications + * to the public list. + * Private list is assumed to be not accessible to other threads yet. + * + * @public: public list + * @private: private list + */ +static void smk_list_swap_rcu(struct list_head *public, + struct list_head *private) +{ + struct list_head *first, *last; + + if (list_empty(public)) { + list_splice_init_rcu(private, public, synchronize_rcu); + } else { + /* Remember public list before replacing it */ + first = public->next; + last = public->prev; + + /* Publish private list in place of public in RCU-safe way */ + private->prev->next = public; + private->next->prev = public; + rcu_assign_pointer(public->next, private->next); + public->prev = private->prev; + + synchronize_rcu(); + + /* When all readers are done with the old public list, + * attach it in place of private */ + private->next = first; + private->prev = last; + first->prev = private; + last->next = private; + } +} + +/** + * smk_parse_label_list - parse list of Smack labels, separated by spaces + * + * @data: the string to parse + * @private: destination list + * + * Returns zero on success or error code, as appropriate + */ +static int smk_parse_label_list(char *data, struct list_head *list) +{ + char *tok; + struct smack_known *skp; + struct smack_known_list_elem *sklep; + + while ((tok = strsep(&data, " ")) != NULL) { + if (!*tok) + continue; + + skp = smk_import_entry(tok, 0); + if (IS_ERR(skp)) + return PTR_ERR(skp); + + sklep = kzalloc(sizeof(*sklep), GFP_KERNEL); + if (sklep == NULL) + return -ENOMEM; + + sklep->smk_label = skp; + list_add(&sklep->list, list); + } + + return 0; +} + +/** + * smk_destroy_label_list - destroy a list of smack_known_list_elem + * @head: header pointer of the list to destroy + */ +void smk_destroy_label_list(struct list_head *list) +{ + struct smack_known_list_elem *sklep; + struct smack_known_list_elem *sklep2; + + list_for_each_entry_safe(sklep, sklep2, list, list) + kfree(sklep); + + INIT_LIST_HEAD(list); +} + +/** + * smk_write_onlycap - write() for smackfs/onlycap + * @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_onlycap(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + char *data; + LIST_HEAD(list_tmp); + int rc; + + if (!smack_privileged(CAP_MAC_ADMIN)) + return -EPERM; + + if (count > PAGE_SIZE) + return -EINVAL; + + data = memdup_user_nul(buf, count); + if (IS_ERR(data)) + return PTR_ERR(data); + + rc = smk_parse_label_list(data, &list_tmp); + kfree(data); + + /* + * Clear the smack_onlycap on invalid label errors. This means + * that we can pass a null string to unset the onlycap value. + * + * Importing will also reject a label beginning with '-', + * so "-usecapabilities" will also work. + * + * But do so only on invalid label, not on system errors. + * The invalid label must be first to count as clearing attempt. + */ + if (!rc || (rc == -EINVAL && list_empty(&list_tmp))) { + mutex_lock(&smack_onlycap_lock); + smk_list_swap_rcu(&smack_onlycap_list, &list_tmp); + mutex_unlock(&smack_onlycap_lock); + rc = count; + } + + smk_destroy_label_list(&list_tmp); + + return rc; +} + +static const struct file_operations smk_onlycap_ops = { + .open = smk_open_onlycap, + .read = seq_read, + .write = smk_write_onlycap, + .llseek = seq_lseek, + .release = seq_release, +}; + +#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; + struct smack_known *skp; + int rc = count; + + if (!smack_privileged(CAP_MAC_ADMIN)) + return -EPERM; + + if (count > PAGE_SIZE) + return -EINVAL; + + data = memdup_user_nul(buf, count); + if (IS_ERR(data)) + return PTR_ERR(data); + + /* + * Clear the smack_unconfined on invalid label errors. This means + * that we can pass a null string to unset the unconfined value. + * + * Importing will also reject a label beginning with '-', + * so "-confine" will also work. + * + * But do so only on invalid label, not on system errors. + */ + skp = smk_import_entry(data, count); + if (PTR_ERR(skp) == -EINVAL) + skp = NULL; + else if (IS_ERR(skp)) { + rc = PTR_ERR(skp); + goto freeout; + } + + smack_unconfined = skp; + +freeout: + 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 + * @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_logging(struct file *filp, char __user *buf, + size_t count, loff_t *ppos) +{ + char temp[32]; + ssize_t rc; + + if (*ppos != 0) + return 0; + + sprintf(temp, "%d\n", log_policy); + rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp)); + return rc; +} + +/** + * smk_write_logging - write() for /smack/logging + * @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_logging(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + char temp[32]; + int i; + + if (!smack_privileged(CAP_MAC_ADMIN)) + return -EPERM; + + if (count >= sizeof(temp) || count == 0) + return -EINVAL; + + if (copy_from_user(temp, buf, count) != 0) + return -EFAULT; + + temp[count] = '\0'; + + if (sscanf(temp, "%d", &i) != 1) + return -EINVAL; + if (i < 0 || i > 3) + return -EINVAL; + log_policy = i; + return count; +} + + + +static const struct file_operations smk_logging_ops = { + .read = smk_read_logging, + .write = smk_write_logging, + .llseek = default_llseek, +}; + +/* + * Seq_file read operations for /smack/load-self + */ + +static void *load_self_seq_start(struct seq_file *s, loff_t *pos) +{ + struct task_smack *tsp = current_security(); + + return smk_seq_start(s, pos, &tsp->smk_rules); +} + +static void *load_self_seq_next(struct seq_file *s, void *v, loff_t *pos) +{ + struct task_smack *tsp = current_security(); + + return smk_seq_next(s, v, pos, &tsp->smk_rules); +} + +static int load_self_seq_show(struct seq_file *s, void *v) +{ + struct list_head *list = v; + struct smack_rule *srp = + list_entry_rcu(list, struct smack_rule, list); + + smk_rule_show(s, srp, SMK_LABELLEN); + + return 0; +} + +static const struct seq_operations load_self_seq_ops = { + .start = load_self_seq_start, + .next = load_self_seq_next, + .show = load_self_seq_show, + .stop = smk_seq_stop, +}; + + +/** + * smk_open_load_self - open() for /smack/load-self2 + * @inode: inode structure representing file + * @file: "load" file pointer + * + * For reading, use load_seq_* seq_file reading operations. + */ +static int smk_open_load_self(struct inode *inode, struct file *file) +{ + return seq_open(file, &load_self_seq_ops); +} + +/** + * smk_write_load_self - write() for /smack/load-self + * @file: file pointer, not actually used + * @buf: where to get the data from + * @count: bytes sent + * @ppos: where to start - must be 0 + * + */ +static ssize_t smk_write_load_self(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct task_smack *tsp = current_security(); + + return smk_write_rules_list(file, buf, count, ppos, &tsp->smk_rules, + &tsp->smk_rules_lock, SMK_FIXED24_FMT); +} + +static const struct file_operations smk_load_self_ops = { + .open = smk_open_load_self, + .read = seq_read, + .llseek = seq_lseek, + .write = smk_write_load_self, + .release = seq_release, +}; + +/** + * smk_user_access - handle access check transaction + * @file: file pointer + * @buf: data from user space + * @count: bytes sent + * @ppos: where to start - must be 0 + */ +static ssize_t smk_user_access(struct file *file, const char __user *buf, + size_t count, loff_t *ppos, int format) +{ + struct smack_parsed_rule rule; + char *data; + int res; + + data = simple_transaction_get(file, buf, count); + if (IS_ERR(data)) + return PTR_ERR(data); + + if (format == SMK_FIXED24_FMT) { + if (count < SMK_LOADLEN) + return -EINVAL; + res = smk_parse_rule(data, &rule, 0); + } else { + /* + * simple_transaction_get() returns null-terminated data + */ + res = smk_parse_long_rule(data, &rule, 0, 3); + } + + if (res >= 0) + res = smk_access(rule.smk_subject, rule.smk_object, + rule.smk_access1, NULL); + else if (res != -ENOENT) + return res; + + /* + * smk_access() can return a value > 0 in the "bringup" case. + */ + data[0] = res >= 0 ? '1' : '0'; + data[1] = '\0'; + + simple_transaction_set(file, 2); + + if (format == SMK_FIXED24_FMT) + return SMK_LOADLEN; + return count; +} + +/** + * smk_write_access - handle access check transaction + * @file: file pointer + * @buf: data from user space + * @count: bytes sent + * @ppos: where to start - must be 0 + */ +static ssize_t smk_write_access(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + return smk_user_access(file, buf, count, ppos, SMK_FIXED24_FMT); +} + +static const struct file_operations smk_access_ops = { + .write = smk_write_access, + .read = simple_transaction_read, + .release = simple_transaction_release, + .llseek = generic_file_llseek, +}; + + +/* + * Seq_file read operations for /smack/load2 + */ + +static int load2_seq_show(struct seq_file *s, void *v) +{ + struct list_head *list = v; + struct smack_master_list *smlp = + list_entry_rcu(list, struct smack_master_list, list); + + smk_rule_show(s, smlp->smk_rule, SMK_LONGLABEL); + + return 0; +} + +static const struct seq_operations load2_seq_ops = { + .start = load2_seq_start, + .next = load2_seq_next, + .show = load2_seq_show, + .stop = smk_seq_stop, +}; + +/** + * smk_open_load2 - open() for /smack/load2 + * @inode: inode structure representing file + * @file: "load2" file pointer + * + * For reading, use load2_seq_* seq_file reading operations. + */ +static int smk_open_load2(struct inode *inode, struct file *file) +{ + return seq_open(file, &load2_seq_ops); +} + +/** + * smk_write_load2 - write() for /smack/load2 + * @file: file pointer, not actually used + * @buf: where to get the data from + * @count: bytes sent + * @ppos: where to start - must be 0 + * + */ +static ssize_t smk_write_load2(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + /* + * Must have privilege. + */ + if (!smack_privileged(CAP_MAC_ADMIN)) + return -EPERM; + + return smk_write_rules_list(file, buf, count, ppos, NULL, NULL, + SMK_LONG_FMT); +} + +static const struct file_operations smk_load2_ops = { + .open = smk_open_load2, + .read = seq_read, + .llseek = seq_lseek, + .write = smk_write_load2, + .release = seq_release, +}; + +/* + * Seq_file read operations for /smack/load-self2 + */ + +static void *load_self2_seq_start(struct seq_file *s, loff_t *pos) +{ + struct task_smack *tsp = current_security(); + + return smk_seq_start(s, pos, &tsp->smk_rules); +} + +static void *load_self2_seq_next(struct seq_file *s, void *v, loff_t *pos) +{ + struct task_smack *tsp = current_security(); + + return smk_seq_next(s, v, pos, &tsp->smk_rules); +} + +static int load_self2_seq_show(struct seq_file *s, void *v) +{ + struct list_head *list = v; + struct smack_rule *srp = + list_entry_rcu(list, struct smack_rule, list); + + smk_rule_show(s, srp, SMK_LONGLABEL); + + return 0; +} + +static const struct seq_operations load_self2_seq_ops = { + .start = load_self2_seq_start, + .next = load_self2_seq_next, + .show = load_self2_seq_show, + .stop = smk_seq_stop, +}; + +/** + * smk_open_load_self2 - open() for /smack/load-self2 + * @inode: inode structure representing file + * @file: "load" file pointer + * + * For reading, use load_seq_* seq_file reading operations. + */ +static int smk_open_load_self2(struct inode *inode, struct file *file) +{ + return seq_open(file, &load_self2_seq_ops); +} + +/** + * smk_write_load_self2 - write() for /smack/load-self2 + * @file: file pointer, not actually used + * @buf: where to get the data from + * @count: bytes sent + * @ppos: where to start - must be 0 + * + */ +static ssize_t smk_write_load_self2(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct task_smack *tsp = current_security(); + + return smk_write_rules_list(file, buf, count, ppos, &tsp->smk_rules, + &tsp->smk_rules_lock, SMK_LONG_FMT); +} + +static const struct file_operations smk_load_self2_ops = { + .open = smk_open_load_self2, + .read = seq_read, + .llseek = seq_lseek, + .write = smk_write_load_self2, + .release = seq_release, +}; + +/** + * smk_write_access2 - handle access check transaction + * @file: file pointer + * @buf: data from user space + * @count: bytes sent + * @ppos: where to start - must be 0 + */ +static ssize_t smk_write_access2(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + return smk_user_access(file, buf, count, ppos, SMK_LONG_FMT); +} + +static const struct file_operations smk_access2_ops = { + .write = smk_write_access2, + .read = simple_transaction_read, + .release = simple_transaction_release, + .llseek = generic_file_llseek, +}; + +/** + * smk_write_revoke_subj - write() for /smack/revoke-subject + * @file: file pointer + * @buf: data from user space + * @count: bytes sent + * @ppos: where to start - must be 0 + */ +static ssize_t smk_write_revoke_subj(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + char *data; + const char *cp; + struct smack_known *skp; + struct smack_rule *sp; + struct list_head *rule_list; + struct mutex *rule_lock; + int rc = count; + + if (*ppos != 0) + return -EINVAL; + + if (!smack_privileged(CAP_MAC_ADMIN)) + return -EPERM; + + if (count == 0 || count > SMK_LONGLABEL) + return -EINVAL; + + data = memdup_user(buf, count); + if (IS_ERR(data)) + return PTR_ERR(data); + + cp = smk_parse_smack(data, count); + if (IS_ERR(cp)) { + rc = PTR_ERR(cp); + goto out_data; + } + + skp = smk_find_entry(cp); + if (skp == NULL) + goto out_cp; + + rule_list = &skp->smk_rules; + rule_lock = &skp->smk_rules_lock; + + mutex_lock(rule_lock); + + list_for_each_entry_rcu(sp, rule_list, list) + sp->smk_access = 0; + + mutex_unlock(rule_lock); + +out_cp: + kfree(cp); +out_data: + kfree(data); + + return rc; +} + +static const struct file_operations smk_revoke_subj_ops = { + .write = smk_write_revoke_subj, + .read = simple_transaction_read, + .release = simple_transaction_release, + .llseek = generic_file_llseek, +}; + +/** + * smk_init_sysfs - initialize /sys/fs/smackfs + * + */ +static int smk_init_sysfs(void) +{ + return sysfs_create_mount_point(fs_kobj, "smackfs"); +} + +/** + * smk_write_change_rule - write() for /smack/change-rule + * @file: file pointer + * @buf: data from user space + * @count: bytes sent + * @ppos: where to start - must be 0 + */ +static ssize_t smk_write_change_rule(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + /* + * Must have privilege. + */ + if (!smack_privileged(CAP_MAC_ADMIN)) + return -EPERM; + + return smk_write_rules_list(file, buf, count, ppos, NULL, NULL, + SMK_CHANGE_FMT); +} + +static const struct file_operations smk_change_rule_ops = { + .write = smk_write_change_rule, + .read = simple_transaction_read, + .release = simple_transaction_release, + .llseek = generic_file_llseek, +}; + +/** + * 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; + + /* Enough data must be present */ + if (count == 0 || count > PAGE_SIZE) + return -EINVAL; + + data = memdup_user_nul(buf, count); + if (IS_ERR(data)) + return PTR_ERR(data); + + skp = smk_import_entry(data, count); + if (IS_ERR(skp)) + rc = PTR_ERR(skp); + else + smack_syslog_label = skp; + + kfree(data); + return rc; +} + +static const struct file_operations smk_syslog_ops = { + .read = smk_read_syslog, + .write = smk_write_syslog, + .llseek = default_llseek, +}; + +/* + * Seq_file read operations for /smack/relabel-self + */ + +static void *relabel_self_seq_start(struct seq_file *s, loff_t *pos) +{ + struct task_smack *tsp = current_security(); + + return smk_seq_start(s, pos, &tsp->smk_relabel); +} + +static void *relabel_self_seq_next(struct seq_file *s, void *v, loff_t *pos) +{ + struct task_smack *tsp = current_security(); + + return smk_seq_next(s, v, pos, &tsp->smk_relabel); +} + +static int relabel_self_seq_show(struct seq_file *s, void *v) +{ + struct list_head *list = v; + struct smack_known_list_elem *sklep = + list_entry(list, struct smack_known_list_elem, list); + + seq_puts(s, sklep->smk_label->smk_known); + seq_putc(s, ' '); + + return 0; +} + +static const struct seq_operations relabel_self_seq_ops = { + .start = relabel_self_seq_start, + .next = relabel_self_seq_next, + .show = relabel_self_seq_show, + .stop = smk_seq_stop, +}; + +/** + * smk_open_relabel_self - open() for /smack/relabel-self + * @inode: inode structure representing file + * @file: "relabel-self" file pointer + * + * Connect our relabel_self_seq_* operations with /smack/relabel-self + * file_operations + */ +static int smk_open_relabel_self(struct inode *inode, struct file *file) +{ + return seq_open(file, &relabel_self_seq_ops); +} + +/** + * smk_write_relabel_self - write() for /smack/relabel-self + * @file: file pointer, not actually used + * @buf: where to get the data from + * @count: bytes sent + * @ppos: where to start - must be 0 + * + */ +static ssize_t smk_write_relabel_self(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + char *data; + int rc; + LIST_HEAD(list_tmp); + + /* + * Must have privilege. + */ + if (!smack_privileged(CAP_MAC_ADMIN)) + return -EPERM; + + /* + * No partial write. + * Enough data must be present. + */ + if (*ppos != 0) + return -EINVAL; + if (count == 0 || count > PAGE_SIZE) + return -EINVAL; + + data = memdup_user_nul(buf, count); + if (IS_ERR(data)) + return PTR_ERR(data); + + rc = smk_parse_label_list(data, &list_tmp); + kfree(data); + + if (!rc || (rc == -EINVAL && list_empty(&list_tmp))) { + struct cred *new; + struct task_smack *tsp; + + new = prepare_creds(); + if (!new) { + rc = -ENOMEM; + goto out; + } + tsp = new->security; + smk_destroy_label_list(&tsp->smk_relabel); + list_splice(&list_tmp, &tsp->smk_relabel); + commit_creds(new); + return count; + } +out: + smk_destroy_label_list(&list_tmp); + return rc; +} + +static const struct file_operations smk_relabel_self_ops = { + .open = smk_open_relabel_self, + .read = seq_read, + .llseek = seq_lseek, + .write = smk_write_relabel_self, + .release = seq_release, +}; + +/** + * smk_read_ptrace - read() for /smack/ptrace + * @filp: file pointer, not actually used + * @buf: where to put the result + * @count: maximum to send along + * @ppos: where to start + * + * Returns number of bytes read or error code, as appropriate + */ +static ssize_t smk_read_ptrace(struct file *filp, char __user *buf, + size_t count, loff_t *ppos) +{ + char temp[32]; + ssize_t rc; + + if (*ppos != 0) + return 0; + + sprintf(temp, "%d\n", smack_ptrace_rule); + rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp)); + return rc; +} + +/** + * smk_write_ptrace - write() for /smack/ptrace + * @file: file pointer + * @buf: data from user space + * @count: bytes sent + * @ppos: where to start - must be 0 + */ +static ssize_t smk_write_ptrace(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + char temp[32]; + int i; + + if (!smack_privileged(CAP_MAC_ADMIN)) + return -EPERM; + + if (*ppos != 0 || count >= sizeof(temp) || count == 0) + return -EINVAL; + + if (copy_from_user(temp, buf, count) != 0) + return -EFAULT; + + temp[count] = '\0'; + + if (sscanf(temp, "%d", &i) != 1) + return -EINVAL; + if (i < SMACK_PTRACE_DEFAULT || i > SMACK_PTRACE_MAX) + return -EINVAL; + smack_ptrace_rule = i; + + return count; +} + +static const struct file_operations smk_ptrace_ops = { + .write = smk_write_ptrace, + .read = smk_read_ptrace, + .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 the smack filesystem + * + * Returns 0 on success, an error code on failure + */ +static int smk_fill_super(struct super_block *sb, void *data, int silent) +{ + int rc; + struct inode *root_inode; + + static const struct tree_descr smack_files[] = { + [SMK_LOAD] = { + "load", &smk_load_ops, S_IRUGO|S_IWUSR}, + [SMK_CIPSO] = { + "cipso", &smk_cipso_ops, S_IRUGO|S_IWUSR}, + [SMK_DOI] = { + "doi", &smk_doi_ops, S_IRUGO|S_IWUSR}, + [SMK_DIRECT] = { + "direct", &smk_direct_ops, S_IRUGO|S_IWUSR}, + [SMK_AMBIENT] = { + "ambient", &smk_ambient_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] = { + "logging", &smk_logging_ops, S_IRUGO|S_IWUSR}, + [SMK_LOAD_SELF] = { + "load-self", &smk_load_self_ops, S_IRUGO|S_IWUGO}, + [SMK_ACCESSES] = { + "access", &smk_access_ops, S_IRUGO|S_IWUGO}, + [SMK_MAPPED] = { + "mapped", &smk_mapped_ops, S_IRUGO|S_IWUSR}, + [SMK_LOAD2] = { + "load2", &smk_load2_ops, S_IRUGO|S_IWUSR}, + [SMK_LOAD_SELF2] = { + "load-self2", &smk_load_self2_ops, S_IRUGO|S_IWUGO}, + [SMK_ACCESS2] = { + "access2", &smk_access2_ops, S_IRUGO|S_IWUGO}, + [SMK_CIPSO2] = { + "cipso2", &smk_cipso2_ops, S_IRUGO|S_IWUSR}, + [SMK_REVOKE_SUBJ] = { + "revoke-subject", &smk_revoke_subj_ops, + 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}, + [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 +#if IS_ENABLED(CONFIG_IPV6) + [SMK_NET6ADDR] = { + "ipv6host", &smk_net6addr_ops, S_IRUGO|S_IWUSR}, +#endif /* CONFIG_IPV6 */ + [SMK_RELABEL_SELF] = { + "relabel-self", &smk_relabel_self_ops, + S_IRUGO|S_IWUGO}, + /* last one */ + {""} + }; + + rc = simple_fill_super(sb, SMACK_MAGIC, smack_files); + if (rc != 0) { + printk(KERN_ERR "%s failed %d while creating inodes\n", + __func__, rc); + return rc; + } + + root_inode = d_inode(sb->s_root); + + return 0; +} + +/** + * smk_mount - get the smackfs superblock + * @fs_type: passed along without comment + * @flags: passed along without comment + * @dev_name: passed along without comment + * @data: passed along without comment + * + * Just passes everything along. + * + * Returns what the lower level code does. + */ +static struct dentry *smk_mount(struct file_system_type *fs_type, + int flags, const char *dev_name, void *data) +{ + return mount_single(fs_type, flags, data, smk_fill_super); +} + +static struct file_system_type smk_fs_type = { + .name = "smackfs", + .mount = smk_mount, + .kill_sb = kill_litter_super, +}; + +static struct vfsmount *smackfs_mount; + +static int __init smk_preset_netlabel(struct smack_known *skp) +{ + skp->smk_netlabel.domain = skp->smk_known; + skp->smk_netlabel.flags = + NETLBL_SECATTR_DOMAIN | NETLBL_SECATTR_MLS_LVL; + return smk_netlbl_mls(smack_cipso_direct, skp->smk_known, + &skp->smk_netlabel, strlen(skp->smk_known)); +} + +/** + * init_smk_fs - get the smackfs superblock + * + * register the smackfs + * + * Do not register smackfs if Smack wasn't enabled + * on boot. We can not put this method normally under the + * smack_init() code path since the security subsystem get + * initialized before the vfs caches. + * + * Returns true if we were not chosen on boot or if + * we were chosen and filesystem registration succeeded. + */ +static int __init init_smk_fs(void) +{ + int err; + int rc; + + if (smack_enabled == 0) + return 0; + + err = smk_init_sysfs(); + if (err) + printk(KERN_ERR "smackfs: sysfs mountpoint problem.\n"); + + err = register_filesystem(&smk_fs_type); + if (!err) { + smackfs_mount = kern_mount(&smk_fs_type); + if (IS_ERR(smackfs_mount)) { + printk(KERN_ERR "smackfs: could not mount!\n"); + err = PTR_ERR(smackfs_mount); + smackfs_mount = NULL; + } + } + + smk_cipso_doi(); + smk_unlbl_ambient(NULL); + + rc = smk_preset_netlabel(&smack_known_floor); + if (err == 0 && rc < 0) + err = rc; + rc = smk_preset_netlabel(&smack_known_hat); + if (err == 0 && rc < 0) + err = rc; + rc = smk_preset_netlabel(&smack_known_huh); + if (err == 0 && rc < 0) + err = rc; + rc = smk_preset_netlabel(&smack_known_star); + if (err == 0 && rc < 0) + err = rc; + rc = smk_preset_netlabel(&smack_known_web); + if (err == 0 && rc < 0) + err = rc; + + return err; +} + +__initcall(init_smk_fs); |