| /* |
| * 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 <net/net_namespace.h> |
| #include <net/netlabel.h> |
| #include <net/cipso_ipv4.h> |
| #include <linux/seq_file.h> |
| #include <linux/ctype.h> |
| #include <linux/audit.h> |
| #include "smack.h" |
| |
| /* |
| * 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_NETLBLADDR = 8, /* single label hosts */ |
| SMK_ONLYCAP = 9, /* the only "capable" label */ |
| }; |
| |
| /* |
| * List locks |
| */ |
| static DEFINE_MUTEX(smack_list_lock); |
| static DEFINE_MUTEX(smack_cipso_lock); |
| static DEFINE_MUTEX(smack_ambient_lock); |
| static DEFINE_MUTEX(smk_netlbladdr_lock); |
| |
| /* |
| * This is the "ambient" label for network traffic. |
| * If it isn't somehow marked, use this. |
| * It can be reset via smackfs/ambient |
| */ |
| char *smack_net_ambient = smack_known_floor.smk_known; |
| |
| /* |
| * 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; |
| |
| /* |
| * Unless a process is running with this label even |
| * having CAP_MAC_OVERRIDE isn't enough to grant |
| * privilege to violate MAC policy. If no label is |
| * designated (the NULL case) capabilities apply to |
| * everyone. It is expected that the hat (^) label |
| * will be used if any label is used. |
| */ |
| char *smack_onlycap; |
| |
| /* |
| * 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_netlbladdr_list); |
| LIST_HEAD(smack_rule_list); |
| |
| static int smk_cipso_doi_value = SMACK_CIPSO_DOI_DEFAULT; |
| |
| const char *smack_cipso_option = SMACK_CIPSO_OPTION; |
| |
| |
| #define SEQ_READ_FINISHED 1 |
| |
| /* |
| * 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_ACCESS "rwxa" |
| #define SMK_ACCESSLEN (sizeof(SMK_ACCESS) - 1) |
| #define SMK_LOADLEN (SMK_LABELLEN + SMK_LABELLEN + SMK_ACCESSLEN) |
| |
| /** |
| * smk_netlabel_audit_set - fill a netlbl_audit struct |
| * @nap: structure to fill |
| */ |
| static void smk_netlabel_audit_set(struct netlbl_audit *nap) |
| { |
| nap->loginuid = audit_get_loginuid(current); |
| nap->sessionid = audit_get_sessionid(current); |
| nap->secid = smack_to_secid(current_security()); |
| } |
| |
| /* |
| * Values for parsing single label host rules |
| * "1.2.3.4 X" |
| * "192.168.138.129/32 abcdefghijklmnopqrstuvw" |
| */ |
| #define SMK_NETLBLADDRMIN 9 |
| #define SMK_NETLBLADDRMAX 42 |
| |
| /* |
| * Seq_file read operations for /smack/load |
| */ |
| |
| static void *load_seq_start(struct seq_file *s, loff_t *pos) |
| { |
| if (*pos == SEQ_READ_FINISHED) |
| return NULL; |
| if (list_empty(&smack_rule_list)) |
| return NULL; |
| return smack_rule_list.next; |
| } |
| |
| static void *load_seq_next(struct seq_file *s, void *v, loff_t *pos) |
| { |
| struct list_head *list = v; |
| |
| if (list_is_last(list, &smack_rule_list)) { |
| *pos = SEQ_READ_FINISHED; |
| return NULL; |
| } |
| return list->next; |
| } |
| |
| static int load_seq_show(struct seq_file *s, void *v) |
| { |
| struct list_head *list = v; |
| struct smack_rule *srp = |
| list_entry(list, struct smack_rule, list); |
| |
| seq_printf(s, "%s %s", (char *)srp->smk_subject, |
| (char *)srp->smk_object); |
| |
| 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 == 0) |
| seq_putc(s, '-'); |
| |
| seq_putc(s, '\n'); |
| |
| return 0; |
| } |
| |
| static void load_seq_stop(struct seq_file *s, void *v) |
| { |
| /* No-op */ |
| } |
| |
| static struct seq_operations load_seq_ops = { |
| .start = load_seq_start, |
| .next = load_seq_next, |
| .show = load_seq_show, |
| .stop = load_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_set_access - add a rule to the rule list |
| * @srp: the new rule to add |
| * |
| * 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_rule *srp) |
| { |
| struct smack_rule *sp; |
| int ret = 0; |
| int found; |
| mutex_lock(&smack_list_lock); |
| |
| found = 0; |
| list_for_each_entry_rcu(sp, &smack_rule_list, list) { |
| if (sp->smk_subject == srp->smk_subject && |
| sp->smk_object == srp->smk_object) { |
| found = 1; |
| sp->smk_access = srp->smk_access; |
| break; |
| } |
| } |
| if (found == 0) |
| list_add_rcu(&srp->list, &smack_rule_list); |
| |
| mutex_unlock(&smack_list_lock); |
| |
| return ret; |
| } |
| |
| /** |
| * 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 |
| * |
| * Get one smack access rule from above. |
| * The format is exactly: |
| * char subject[SMK_LABELLEN] |
| * char object[SMK_LABELLEN] |
| * char access[SMK_ACCESSLEN] |
| * |
| * writes must be SMK_LABELLEN+SMK_LABELLEN+SMK_ACCESSLEN bytes. |
| */ |
| static ssize_t smk_write_load(struct file *file, const char __user *buf, |
| size_t count, loff_t *ppos) |
| { |
| struct smack_rule *rule; |
| char *data; |
| int rc = -EINVAL; |
| |
| /* |
| * Must have privilege. |
| * No partial writes. |
| * Enough data must be present. |
| */ |
| if (!capable(CAP_MAC_ADMIN)) |
| return -EPERM; |
| |
| if (*ppos != 0 || count != SMK_LOADLEN) |
| return -EINVAL; |
| |
| data = kzalloc(count, GFP_KERNEL); |
| if (data == NULL) |
| return -ENOMEM; |
| |
| if (copy_from_user(data, buf, count) != 0) { |
| rc = -EFAULT; |
| goto out; |
| } |
| |
| rule = kzalloc(sizeof(*rule), GFP_KERNEL); |
| if (rule == NULL) { |
| rc = -ENOMEM; |
| goto out; |
| } |
| |
| rule->smk_subject = smk_import(data, 0); |
| if (rule->smk_subject == NULL) |
| goto out_free_rule; |
| |
| rule->smk_object = smk_import(data + SMK_LABELLEN, 0); |
| if (rule->smk_object == NULL) |
| goto out_free_rule; |
| |
| rule->smk_access = 0; |
| |
| switch (data[SMK_LABELLEN + SMK_LABELLEN]) { |
| case '-': |
| break; |
| case 'r': |
| case 'R': |
| rule->smk_access |= MAY_READ; |
| break; |
| default: |
| goto out_free_rule; |
| } |
| |
| switch (data[SMK_LABELLEN + SMK_LABELLEN + 1]) { |
| case '-': |
| break; |
| case 'w': |
| case 'W': |
| rule->smk_access |= MAY_WRITE; |
| break; |
| default: |
| goto out_free_rule; |
| } |
| |
| switch (data[SMK_LABELLEN + SMK_LABELLEN + 2]) { |
| case '-': |
| break; |
| case 'x': |
| case 'X': |
| rule->smk_access |= MAY_EXEC; |
| break; |
| default: |
| goto out_free_rule; |
| } |
| |
| switch (data[SMK_LABELLEN + SMK_LABELLEN + 3]) { |
| case '-': |
| break; |
| case 'a': |
| case 'A': |
| rule->smk_access |= MAY_APPEND; |
| break; |
| default: |
| goto out_free_rule; |
| } |
| |
| rc = smk_set_access(rule); |
| |
| if (!rc) |
| rc = count; |
| goto out; |
| |
| out_free_rule: |
| kfree(rule); |
| out: |
| kfree(data); |
| return rc; |
| } |
| |
| 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); |
| if (doip == NULL) |
| panic("smack: Failed to initialize cipso DOI.\n"); |
| 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); |
| kfree(doip); |
| 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); |
| } |
| |
| rc = netlbl_cfg_unlbl_map_add(smack_net_ambient, 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) |
| { |
| if (*pos == SEQ_READ_FINISHED) |
| return NULL; |
| if (list_empty(&smack_known_list)) |
| return NULL; |
| |
| return smack_known_list.next; |
| } |
| |
| static void *cipso_seq_next(struct seq_file *s, void *v, loff_t *pos) |
| { |
| struct list_head *list = v; |
| |
| /* |
| * labels with no associated cipso value wont be printed |
| * in cipso_seq_show |
| */ |
| if (list_is_last(list, &smack_known_list)) { |
| *pos = SEQ_READ_FINISHED; |
| return NULL; |
| } |
| |
| return list->next; |
| } |
| |
| /* |
| * 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(list, struct smack_known, list); |
| struct smack_cipso *scp = skp->smk_cipso; |
| char *cbp; |
| char sep = '/'; |
| int cat = 1; |
| int i; |
| unsigned char m; |
| |
| if (scp == NULL) |
| return 0; |
| |
| seq_printf(s, "%s %3d", (char *)&skp->smk_known, scp->smk_level); |
| |
| cbp = scp->smk_catset; |
| for (i = 0; i < SMK_LABELLEN; i++) |
| for (m = 0x80; m != 0; m >>= 1) { |
| if (m & cbp[i]) { |
| seq_printf(s, "%c%d", sep, cat); |
| sep = ','; |
| } |
| cat++; |
| } |
| |
| seq_putc(s, '\n'); |
| |
| return 0; |
| } |
| |
| static void cipso_seq_stop(struct seq_file *s, void *v) |
| { |
| /* No-op */ |
| } |
| |
| static struct seq_operations cipso_seq_ops = { |
| .start = cipso_seq_start, |
| .stop = cipso_seq_stop, |
| .next = cipso_seq_next, |
| .show = cipso_seq_show, |
| }; |
| |
| /** |
| * 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_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) |
| { |
| struct smack_known *skp; |
| struct smack_cipso *scp = NULL; |
| char mapcatset[SMK_LABELLEN]; |
| int maplevel; |
| 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 (!capable(CAP_MAC_ADMIN)) |
| return -EPERM; |
| if (*ppos != 0) |
| return -EINVAL; |
| if (count < SMK_CIPSOMIN || count > SMK_CIPSOMAX) |
| return -EINVAL; |
| |
| data = kzalloc(count + 1, GFP_KERNEL); |
| if (data == NULL) |
| return -ENOMEM; |
| |
| if (copy_from_user(data, buf, count) != 0) { |
| rc = -EFAULT; |
| goto unlockedout; |
| } |
| |
| /* labels cannot begin with a '-' */ |
| if (data[0] == '-') { |
| rc = -EINVAL; |
| goto unlockedout; |
| } |
| data[count] = '\0'; |
| 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 (skp == NULL) |
| goto out; |
| |
| rule += SMK_LABELLEN; |
| ret = sscanf(rule, "%d", &maplevel); |
| if (ret != 1 || maplevel > SMACK_CIPSO_MAXLEVEL) |
| goto out; |
| |
| rule += SMK_DIGITLEN; |
| ret = sscanf(rule, "%d", &catlen); |
| if (ret != 1 || catlen > SMACK_CIPSO_MAXCATNUM) |
| goto out; |
| |
| if (count != (SMK_CIPSOMIN + catlen * SMK_DIGITLEN)) |
| goto out; |
| |
| memset(mapcatset, 0, sizeof(mapcatset)); |
| |
| for (i = 0; i < catlen; i++) { |
| rule += SMK_DIGITLEN; |
| ret = sscanf(rule, "%d", &cat); |
| if (ret != 1 || cat > SMACK_CIPSO_MAXCATVAL) |
| goto out; |
| |
| smack_catset_bit(cat, mapcatset); |
| } |
| |
| if (skp->smk_cipso == NULL) { |
| scp = kzalloc(sizeof(struct smack_cipso), GFP_KERNEL); |
| if (scp == NULL) { |
| rc = -ENOMEM; |
| goto out; |
| } |
| } |
| |
| spin_lock_bh(&skp->smk_cipsolock); |
| |
| if (scp == NULL) |
| scp = skp->smk_cipso; |
| else |
| skp->smk_cipso = scp; |
| |
| scp->smk_level = maplevel; |
| memcpy(scp->smk_catset, mapcatset, sizeof(mapcatset)); |
| |
| spin_unlock_bh(&skp->smk_cipsolock); |
| |
| rc = count; |
| out: |
| mutex_unlock(&smack_cipso_lock); |
| unlockedout: |
| kfree(data); |
| return rc; |
| } |
| |
| 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/netlabel |
| */ |
| |
| static void *netlbladdr_seq_start(struct seq_file *s, loff_t *pos) |
| { |
| if (*pos == SEQ_READ_FINISHED) |
| return NULL; |
| if (list_empty(&smk_netlbladdr_list)) |
| return NULL; |
| return smk_netlbladdr_list.next; |
| } |
| |
| static void *netlbladdr_seq_next(struct seq_file *s, void *v, loff_t *pos) |
| { |
| struct list_head *list = v; |
| |
| if (list_is_last(list, &smk_netlbladdr_list)) { |
| *pos = SEQ_READ_FINISHED; |
| return NULL; |
| } |
| |
| return list->next; |
| } |
| #define BEBITS (sizeof(__be32) * 8) |
| |
| /* |
| * Print host/label pairs |
| */ |
| static int netlbladdr_seq_show(struct seq_file *s, void *v) |
| { |
| struct list_head *list = v; |
| struct smk_netlbladdr *skp = |
| list_entry(list, struct smk_netlbladdr, list); |
| unsigned char *hp = (char *) &skp->smk_host.sin_addr.s_addr; |
| int maskn; |
| u32 temp_mask = be32_to_cpu(skp->smk_mask.s_addr); |
| |
| for (maskn = 0; temp_mask; temp_mask <<= 1, maskn++); |
| |
| seq_printf(s, "%u.%u.%u.%u/%d %s\n", |
| hp[0], hp[1], hp[2], hp[3], maskn, skp->smk_label); |
| |
| return 0; |
| } |
| |
| static void netlbladdr_seq_stop(struct seq_file *s, void *v) |
| { |
| /* No-op */ |
| } |
| |
| static struct seq_operations netlbladdr_seq_ops = { |
| .start = netlbladdr_seq_start, |
| .stop = netlbladdr_seq_stop, |
| .next = netlbladdr_seq_next, |
| .show = netlbladdr_seq_show, |
| }; |
| |
| /** |
| * smk_open_netlbladdr - open() for /smack/netlabel |
| * @inode: inode structure representing file |
| * @file: "netlabel" file pointer |
| * |
| * Connect our netlbladdr_seq_* operations with /smack/netlabel |
| * file_operations |
| */ |
| static int smk_open_netlbladdr(struct inode *inode, struct file *file) |
| { |
| return seq_open(file, &netlbladdr_seq_ops); |
| } |
| |
| /** |
| * smk_netlbladdr_insert |
| * @new : netlabel to insert |
| * |
| * This helper insert netlabel in the smack_netlbladdrs list |
| * sorted by netmask length (longest to smallest) |
| * locked by &smk_netlbladdr_lock in smk_write_netlbladdr |
| * |
| */ |
| static void smk_netlbladdr_insert(struct smk_netlbladdr *new) |
| { |
| struct smk_netlbladdr *m, *m_next; |
| |
| if (list_empty(&smk_netlbladdr_list)) { |
| list_add_rcu(&new->list, &smk_netlbladdr_list); |
| return; |
| } |
| |
| m = list_entry_rcu(smk_netlbladdr_list.next, |
| struct smk_netlbladdr, list); |
| |
| /* the comparison '>' is a bit hacky, but works */ |
| if (new->smk_mask.s_addr > m->smk_mask.s_addr) { |
| list_add_rcu(&new->list, &smk_netlbladdr_list); |
| return; |
| } |
| |
| list_for_each_entry_rcu(m, &smk_netlbladdr_list, list) { |
| if (list_is_last(&m->list, &smk_netlbladdr_list)) { |
| list_add_rcu(&new->list, &m->list); |
| return; |
| } |
| m_next = list_entry_rcu(m->list.next, |
| struct smk_netlbladdr, list); |
| if (new->smk_mask.s_addr > m_next->smk_mask.s_addr) { |
| list_add_rcu(&new->list, &m->list); |
| return; |
| } |
| } |
| } |
| |
| |
| /** |
| * smk_write_netlbladdr - write() for /smack/netlabel |
| * @file: file pointer, not actually used |
| * @buf: where to get the data from |
| * @count: bytes sent |
| * @ppos: where to start |
| * |
| * Accepts only one netlbladdr per write call. |
| * Returns number of bytes written or error code, as appropriate |
| */ |
| static ssize_t smk_write_netlbladdr(struct file *file, const char __user *buf, |
| size_t count, loff_t *ppos) |
| { |
| struct smk_netlbladdr *skp; |
| struct sockaddr_in newname; |
| char smack[SMK_LABELLEN]; |
| char *sp; |
| char data[SMK_NETLBLADDRMAX]; |
| char *host = (char *)&newname.sin_addr.s_addr; |
| int rc; |
| struct netlbl_audit audit_info; |
| struct in_addr mask; |
| unsigned int m; |
| 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 (!capable(CAP_MAC_ADMIN)) |
| return -EPERM; |
| if (*ppos != 0) |
| return -EINVAL; |
| if (count < SMK_NETLBLADDRMIN || count > SMK_NETLBLADDRMAX) |
| return -EINVAL; |
| if (copy_from_user(data, buf, count) != 0) |
| return -EFAULT; |
| |
| data[count] = '\0'; |
| |
| rc = sscanf(data, "%hhd.%hhd.%hhd.%hhd/%d %s", |
| &host[0], &host[1], &host[2], &host[3], &m, smack); |
| if (rc != 6) { |
| rc = sscanf(data, "%hhd.%hhd.%hhd.%hhd %s", |
| &host[0], &host[1], &host[2], &host[3], smack); |
| if (rc != 5) |
| return -EINVAL; |
| m = BEBITS; |
| } |
| if (m > BEBITS) |
| return -EINVAL; |
| |
| /* if smack begins with '-', its an option, don't import it */ |
| if (smack[0] != '-') { |
| sp = smk_import(smack, 0); |
| if (sp == NULL) |
| return -EINVAL; |
| } else { |
| /* check known options */ |
| if (strcmp(smack, smack_cipso_option) == 0) |
| sp = (char *)smack_cipso_option; |
| else |
| return -EINVAL; |
| } |
| |
| for (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_netlbladdr_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(skp, &smk_netlbladdr_list, list) { |
| if (skp->smk_host.sin_addr.s_addr == nsa && |
| skp->smk_mask.s_addr == mask.s_addr) { |
| found = 1; |
| break; |
| } |
| } |
| smk_netlabel_audit_set(&audit_info); |
| |
| if (found == 0) { |
| skp = kzalloc(sizeof(*skp), GFP_KERNEL); |
| if (skp == NULL) |
| rc = -ENOMEM; |
| else { |
| rc = 0; |
| skp->smk_host.sin_addr.s_addr = newname.sin_addr.s_addr; |
| skp->smk_mask.s_addr = mask.s_addr; |
| skp->smk_label = sp; |
| smk_netlbladdr_insert(skp); |
| } |
| } else { |
| /* we delete the unlabeled entry, only if the previous label |
| * wasnt the special CIPSO option */ |
| if (skp->smk_label != smack_cipso_option) |
| rc = netlbl_cfg_unlbl_static_del(&init_net, NULL, |
| &skp->smk_host.sin_addr, &skp->smk_mask, |
| PF_INET, &audit_info); |
| else |
| rc = 0; |
| skp->smk_label = sp; |
| } |
| |
| /* |
| * 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 && sp != smack_cipso_option) |
| rc = netlbl_cfg_unlbl_static_add(&init_net, NULL, |
| &skp->smk_host.sin_addr, &skp->smk_mask, PF_INET, |
| smack_to_secid(skp->smk_label), &audit_info); |
| |
| if (rc == 0) |
| rc = count; |
| |
| mutex_unlock(&smk_netlbladdr_lock); |
| |
| return rc; |
| } |
| |
| static const struct file_operations smk_netlbladdr_ops = { |
| .open = smk_open_netlbladdr, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .write = smk_write_netlbladdr, |
| .release = seq_release, |
| }; |
| |
| /** |
| * 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 (!capable(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, |
| }; |
| |
| /** |
| * 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) |
| { |
| char temp[80]; |
| int i; |
| |
| if (!capable(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; |
| |
| smack_cipso_direct = i; |
| |
| return count; |
| } |
| |
| static const struct file_operations smk_direct_ops = { |
| .read = smk_read_direct, |
| .write = smk_write_direct, |
| }; |
| |
| /** |
| * 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) + 1; |
| |
| if (cn >= asize) |
| rc = simple_read_from_buffer(buf, cn, ppos, |
| smack_net_ambient, 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) |
| { |
| char in[SMK_LABELLEN]; |
| char *oldambient; |
| char *smack; |
| |
| if (!capable(CAP_MAC_ADMIN)) |
| return -EPERM; |
| |
| if (count >= SMK_LABELLEN) |
| return -EINVAL; |
| |
| if (copy_from_user(in, buf, count) != 0) |
| return -EFAULT; |
| |
| smack = smk_import(in, count); |
| if (smack == NULL) |
| return -EINVAL; |
| |
| mutex_lock(&smack_ambient_lock); |
| |
| oldambient = smack_net_ambient; |
| smack_net_ambient = smack; |
| smk_unlbl_ambient(oldambient); |
| |
| mutex_unlock(&smack_ambient_lock); |
| |
| return count; |
| } |
| |
| static const struct file_operations smk_ambient_ops = { |
| .read = smk_read_ambient, |
| .write = smk_write_ambient, |
| }; |
| |
| /** |
| * smk_read_onlycap - read() for /smack/onlycap |
| * @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_onlycap(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_onlycap != NULL) |
| smack = smack_onlycap; |
| |
| asize = strlen(smack) + 1; |
| |
| if (cn >= asize) |
| rc = simple_read_from_buffer(buf, cn, ppos, smack, asize); |
| |
| return rc; |
| } |
| |
| /** |
| * smk_write_onlycap - write() for /smack/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 in[SMK_LABELLEN]; |
| char *sp = current->cred->security; |
| |
| if (!capable(CAP_MAC_ADMIN)) |
| return -EPERM; |
| |
| /* |
| * This can be done using smk_access() but is done |
| * explicitly for clarity. The smk_access() implementation |
| * would use smk_access(smack_onlycap, MAY_WRITE) |
| */ |
| if (smack_onlycap != NULL && smack_onlycap != sp) |
| return -EPERM; |
| |
| if (count >= SMK_LABELLEN) |
| return -EINVAL; |
| |
| if (copy_from_user(in, buf, count) != 0) |
| return -EFAULT; |
| |
| /* |
| * Should the null string be passed in unset the onlycap 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. |
| */ |
| smack_onlycap = smk_import(in, count); |
| |
| return count; |
| } |
| |
| static const struct file_operations smk_onlycap_ops = { |
| .read = smk_read_onlycap, |
| .write = smk_write_onlycap, |
| }; |
| |
| /** |
| * smk_fill_super - fill the /smackfs superblock |
| * @sb: the empty superblock |
| * @data: unused |
| * @silent: unused |
| * |
| * Fill in the well known entries for /smack |
| * |
| * 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 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_NETLBLADDR] = |
| {"netlabel", &smk_netlbladdr_ops, S_IRUGO|S_IWUSR}, |
| [SMK_ONLYCAP] = |
| {"onlycap", &smk_onlycap_ops, S_IRUGO|S_IWUSR}, |
| /* 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 = sb->s_root->d_inode; |
| root_inode->i_security = new_inode_smack(smack_known_floor.smk_known); |
| |
| return 0; |
| } |
| |
| /** |
| * smk_get_sb - 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 |
| * @mnt: passed along without comment |
| * |
| * Just passes everything along. |
| * |
| * Returns what the lower level code does. |
| */ |
| static int smk_get_sb(struct file_system_type *fs_type, |
| int flags, const char *dev_name, void *data, |
| struct vfsmount *mnt) |
| { |
| return get_sb_single(fs_type, flags, data, smk_fill_super, mnt); |
| } |
| |
| static struct file_system_type smk_fs_type = { |
| .name = "smackfs", |
| .get_sb = smk_get_sb, |
| .kill_sb = kill_litter_super, |
| }; |
| |
| static struct vfsmount *smackfs_mount; |
| |
| /** |
| * 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; |
| |
| if (!security_module_enable(&smack_ops)) |
| return 0; |
| |
| 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); |
| |
| return err; |
| } |
| |
| __initcall(init_smk_fs); |