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kernel/auditfilter.c
36.1 KB
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/* auditfilter.c -- filtering of audit events * * Copyright 2003-2004 Red Hat, Inc. * Copyright 2005 Hewlett-Packard Development Company, L.P. * Copyright 2005 IBM Corporation * * 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; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include <linux/kernel.h> #include <linux/audit.h> #include <linux/kthread.h> |
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#include <linux/mutex.h> #include <linux/fs.h> #include <linux/namei.h> |
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#include <linux/netlink.h> |
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#include <linux/sched.h> |
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#include <linux/slab.h> |
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#include <linux/security.h> |
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#include "audit.h" |
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/* * Locking model: * * audit_filter_mutex: * Synchronizes writes and blocking reads of audit's filterlist * data. Rcu is used to traverse the filterlist and access * contents of structs audit_entry, audit_watch and opaque |
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* LSM rules during filtering. If modified, these structures |
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* must be copied and replace their counterparts in the filterlist. * An audit_parent struct is not accessed during filtering, so may * be written directly provided audit_filter_mutex is held. */ |
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/* Audit filter lists, defined in <linux/audit.h> */ |
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struct list_head audit_filter_list[AUDIT_NR_FILTERS] = { LIST_HEAD_INIT(audit_filter_list[0]), LIST_HEAD_INIT(audit_filter_list[1]), LIST_HEAD_INIT(audit_filter_list[2]), LIST_HEAD_INIT(audit_filter_list[3]), LIST_HEAD_INIT(audit_filter_list[4]), LIST_HEAD_INIT(audit_filter_list[5]), #if AUDIT_NR_FILTERS != 6 #error Fix audit_filter_list initialiser #endif }; |
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static struct list_head audit_rules_list[AUDIT_NR_FILTERS] = { LIST_HEAD_INIT(audit_rules_list[0]), LIST_HEAD_INIT(audit_rules_list[1]), LIST_HEAD_INIT(audit_rules_list[2]), LIST_HEAD_INIT(audit_rules_list[3]), LIST_HEAD_INIT(audit_rules_list[4]), LIST_HEAD_INIT(audit_rules_list[5]), }; |
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DEFINE_MUTEX(audit_filter_mutex); |
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static inline void audit_free_rule(struct audit_entry *e) |
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{ |
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int i; |
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struct audit_krule *erule = &e->rule; |
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/* some rules don't have associated watches */ |
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if (erule->watch) audit_put_watch(erule->watch); if (erule->fields) for (i = 0; i < erule->field_count; i++) { struct audit_field *f = &erule->fields[i]; |
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kfree(f->lsm_str); security_audit_rule_free(f->lsm_rule); |
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} |
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kfree(erule->fields); kfree(erule->filterkey); |
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kfree(e); } |
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void audit_free_rule_rcu(struct rcu_head *head) |
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{ struct audit_entry *e = container_of(head, struct audit_entry, rcu); audit_free_rule(e); } |
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/* Initialize an audit filterlist entry. */ static inline struct audit_entry *audit_init_entry(u32 field_count) { struct audit_entry *entry; struct audit_field *fields; entry = kzalloc(sizeof(*entry), GFP_KERNEL); if (unlikely(!entry)) return NULL; fields = kzalloc(sizeof(*fields) * field_count, GFP_KERNEL); if (unlikely(!fields)) { kfree(entry); return NULL; } entry->rule.fields = fields; return entry; } |
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/* Unpack a filter field's string representation from user-space * buffer. */ |
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char *audit_unpack_string(void **bufp, size_t *remain, size_t len) |
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{ char *str; if (!*bufp || (len == 0) || (len > *remain)) return ERR_PTR(-EINVAL); /* Of the currently implemented string fields, PATH_MAX * defines the longest valid length. */ if (len > PATH_MAX) return ERR_PTR(-ENAMETOOLONG); str = kmalloc(len + 1, GFP_KERNEL); if (unlikely(!str)) return ERR_PTR(-ENOMEM); memcpy(str, *bufp, len); str[len] = 0; *bufp += len; *remain -= len; return str; } |
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/* Translate an inode field to kernel respresentation. */ static inline int audit_to_inode(struct audit_krule *krule, struct audit_field *f) { if (krule->listnr != AUDIT_FILTER_EXIT || |
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krule->watch || krule->inode_f || krule->tree || (f->op != Audit_equal && f->op != Audit_not_equal)) |
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return -EINVAL; krule->inode_f = f; return 0; } |
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static __u32 *classes[AUDIT_SYSCALL_CLASSES]; int __init audit_register_class(int class, unsigned *list) { __u32 *p = kzalloc(AUDIT_BITMASK_SIZE * sizeof(__u32), GFP_KERNEL); if (!p) return -ENOMEM; while (*list != ~0U) { unsigned n = *list++; if (n >= AUDIT_BITMASK_SIZE * 32 - AUDIT_SYSCALL_CLASSES) { kfree(p); return -EINVAL; } p[AUDIT_WORD(n)] |= AUDIT_BIT(n); } if (class >= AUDIT_SYSCALL_CLASSES || classes[class]) { kfree(p); return -EINVAL; } classes[class] = p; return 0; } |
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int audit_match_class(int class, unsigned syscall) { |
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if (unlikely(syscall >= AUDIT_BITMASK_SIZE * 32)) |
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return 0; if (unlikely(class >= AUDIT_SYSCALL_CLASSES || !classes[class])) return 0; return classes[class][AUDIT_WORD(syscall)] & AUDIT_BIT(syscall); } |
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#ifdef CONFIG_AUDITSYSCALL |
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static inline int audit_match_class_bits(int class, u32 *mask) { int i; if (classes[class]) { for (i = 0; i < AUDIT_BITMASK_SIZE; i++) if (mask[i] & classes[class][i]) return 0; } return 1; } static int audit_match_signal(struct audit_entry *entry) { struct audit_field *arch = entry->rule.arch_f; if (!arch) { /* When arch is unspecified, we must check both masks on biarch * as syscall number alone is ambiguous. */ return (audit_match_class_bits(AUDIT_CLASS_SIGNAL, entry->rule.mask) && audit_match_class_bits(AUDIT_CLASS_SIGNAL_32, entry->rule.mask)); } switch(audit_classify_arch(arch->val)) { case 0: /* native */ return (audit_match_class_bits(AUDIT_CLASS_SIGNAL, entry->rule.mask)); case 1: /* 32bit on biarch */ return (audit_match_class_bits(AUDIT_CLASS_SIGNAL_32, entry->rule.mask)); default: return 1; } } |
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#endif |
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/* Common user-space to kernel rule translation. */ static inline struct audit_entry *audit_to_entry_common(struct audit_rule *rule) { unsigned listnr; struct audit_entry *entry; |
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int i, err; err = -EINVAL; listnr = rule->flags & ~AUDIT_FILTER_PREPEND; switch(listnr) { default: goto exit_err; |
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#ifdef CONFIG_AUDITSYSCALL case AUDIT_FILTER_ENTRY: |
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if (rule->action == AUDIT_ALWAYS) goto exit_err; |
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case AUDIT_FILTER_EXIT: case AUDIT_FILTER_TASK: #endif |
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case AUDIT_FILTER_USER: case AUDIT_FILTER_TYPE: |
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; } |
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if (unlikely(rule->action == AUDIT_POSSIBLE)) { printk(KERN_ERR "AUDIT_POSSIBLE is deprecated "); goto exit_err; } if (rule->action != AUDIT_NEVER && rule->action != AUDIT_ALWAYS) |
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goto exit_err; if (rule->field_count > AUDIT_MAX_FIELDS) goto exit_err; err = -ENOMEM; |
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entry = audit_init_entry(rule->field_count); if (!entry) |
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goto exit_err; |
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entry->rule.flags = rule->flags & AUDIT_FILTER_PREPEND; entry->rule.listnr = listnr; entry->rule.action = rule->action; entry->rule.field_count = rule->field_count; |
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for (i = 0; i < AUDIT_BITMASK_SIZE; i++) entry->rule.mask[i] = rule->mask[i]; |
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for (i = 0; i < AUDIT_SYSCALL_CLASSES; i++) { int bit = AUDIT_BITMASK_SIZE * 32 - i - 1; __u32 *p = &entry->rule.mask[AUDIT_WORD(bit)]; __u32 *class; if (!(*p & AUDIT_BIT(bit))) continue; *p &= ~AUDIT_BIT(bit); class = classes[i]; if (class) { int j; for (j = 0; j < AUDIT_BITMASK_SIZE; j++) entry->rule.mask[j] |= class[j]; } } |
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return entry; exit_err: return ERR_PTR(err); } |
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static u32 audit_ops[] = { [Audit_equal] = AUDIT_EQUAL, [Audit_not_equal] = AUDIT_NOT_EQUAL, [Audit_bitmask] = AUDIT_BIT_MASK, [Audit_bittest] = AUDIT_BIT_TEST, [Audit_lt] = AUDIT_LESS_THAN, [Audit_gt] = AUDIT_GREATER_THAN, [Audit_le] = AUDIT_LESS_THAN_OR_EQUAL, [Audit_ge] = AUDIT_GREATER_THAN_OR_EQUAL, }; static u32 audit_to_op(u32 op) { u32 n; for (n = Audit_equal; n < Audit_bad && audit_ops[n] != op; n++) ; return n; } |
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/* Translate struct audit_rule to kernel's rule respresentation. * Exists for backward compatibility with userspace. */ static struct audit_entry *audit_rule_to_entry(struct audit_rule *rule) { struct audit_entry *entry; int err = 0; |
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int i; |
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entry = audit_to_entry_common(rule); if (IS_ERR(entry)) goto exit_nofree; for (i = 0; i < rule->field_count; i++) { struct audit_field *f = &entry->rule.fields[i]; |
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u32 n; n = rule->fields[i] & (AUDIT_NEGATE|AUDIT_OPERATORS); /* Support for legacy operators where * AUDIT_NEGATE bit signifies != and otherwise assumes == */ if (n & AUDIT_NEGATE) f->op = Audit_not_equal; else if (!n) f->op = Audit_equal; else f->op = audit_to_op(n); entry->rule.vers_ops = (n & AUDIT_OPERATORS) ? 2 : 1; |
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f->type = rule->fields[i] & ~(AUDIT_NEGATE|AUDIT_OPERATORS); f->val = rule->values[i]; |
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f->uid = INVALID_UID; f->gid = INVALID_GID; |
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err = -EINVAL; |
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if (f->op == Audit_bad) goto exit_free; |
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switch(f->type) { |
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default: |
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goto exit_free; |
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case AUDIT_UID: case AUDIT_EUID: case AUDIT_SUID: case AUDIT_FSUID: |
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case AUDIT_LOGINUID: /* bit ops not implemented for uid comparisons */ if (f->op == Audit_bitmask || f->op == Audit_bittest) goto exit_free; f->uid = make_kuid(current_user_ns(), f->val); if (!uid_valid(f->uid)) goto exit_free; break; |
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case AUDIT_GID: case AUDIT_EGID: case AUDIT_SGID: case AUDIT_FSGID: |
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/* bit ops not implemented for gid comparisons */ if (f->op == Audit_bitmask || f->op == Audit_bittest) goto exit_free; f->gid = make_kgid(current_user_ns(), f->val); if (!gid_valid(f->gid)) goto exit_free; break; case AUDIT_PID: |
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case AUDIT_PERS: |
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case AUDIT_MSGTYPE: |
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case AUDIT_PPID: |
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case AUDIT_DEVMAJOR: case AUDIT_DEVMINOR: case AUDIT_EXIT: case AUDIT_SUCCESS: |
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/* bit ops are only useful on syscall args */ |
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if (f->op == Audit_bitmask || f->op == Audit_bittest) |
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goto exit_free; |
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break; |
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case AUDIT_ARG0: case AUDIT_ARG1: case AUDIT_ARG2: case AUDIT_ARG3: break; |
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/* arch is only allowed to be = or != */ case AUDIT_ARCH: |
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if (f->op != Audit_not_equal && f->op != Audit_equal) |
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goto exit_free; |
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entry->rule.arch_f = f; |
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break; |
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case AUDIT_PERM: if (f->val & ~15) goto exit_free; break; |
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case AUDIT_FILETYPE: |
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if (f->val & ~S_IFMT) |
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goto exit_free; break; |
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case AUDIT_INODE: err = audit_to_inode(&entry->rule, f); if (err) goto exit_free; break; |
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} |
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} |
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if (entry->rule.inode_f && entry->rule.inode_f->op == Audit_not_equal) entry->rule.inode_f = NULL; |
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exit_nofree: return entry; exit_free: audit_free_rule(entry); return ERR_PTR(err); |
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} |
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/* Translate struct audit_rule_data to kernel's rule respresentation. */ static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data, size_t datasz) |
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{ |
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int err = 0; struct audit_entry *entry; void *bufp; |
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size_t remain = datasz - sizeof(struct audit_rule_data); |
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int i; |
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char *str; |
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entry = audit_to_entry_common((struct audit_rule *)data); if (IS_ERR(entry)) goto exit_nofree; |
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bufp = data->buf; entry->rule.vers_ops = 2; for (i = 0; i < data->field_count; i++) { struct audit_field *f = &entry->rule.fields[i]; err = -EINVAL; |
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f->op = audit_to_op(data->fieldflags[i]); if (f->op == Audit_bad) |
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goto exit_free; |
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f->type = data->fields[i]; |
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f->val = data->values[i]; |
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f->uid = INVALID_UID; f->gid = INVALID_GID; |
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f->lsm_str = NULL; f->lsm_rule = NULL; |
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switch(f->type) { |
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case AUDIT_UID: case AUDIT_EUID: case AUDIT_SUID: case AUDIT_FSUID: |
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case AUDIT_LOGINUID: case AUDIT_OBJ_UID: /* bit ops not implemented for uid comparisons */ if (f->op == Audit_bitmask || f->op == Audit_bittest) goto exit_free; f->uid = make_kuid(current_user_ns(), f->val); if (!uid_valid(f->uid)) goto exit_free; break; |
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case AUDIT_GID: case AUDIT_EGID: case AUDIT_SGID: case AUDIT_FSGID: |
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case AUDIT_OBJ_GID: /* bit ops not implemented for gid comparisons */ if (f->op == Audit_bitmask || f->op == Audit_bittest) goto exit_free; f->gid = make_kgid(current_user_ns(), f->val); if (!gid_valid(f->gid)) goto exit_free; break; case AUDIT_PID: |
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case AUDIT_PERS: |
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case AUDIT_MSGTYPE: case AUDIT_PPID: case AUDIT_DEVMAJOR: case AUDIT_DEVMINOR: case AUDIT_EXIT: case AUDIT_SUCCESS: case AUDIT_ARG0: case AUDIT_ARG1: case AUDIT_ARG2: case AUDIT_ARG3: break; |
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case AUDIT_ARCH: entry->rule.arch_f = f; break; |
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case AUDIT_SUBJ_USER: case AUDIT_SUBJ_ROLE: case AUDIT_SUBJ_TYPE: case AUDIT_SUBJ_SEN: case AUDIT_SUBJ_CLR: |
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case AUDIT_OBJ_USER: case AUDIT_OBJ_ROLE: case AUDIT_OBJ_TYPE: case AUDIT_OBJ_LEV_LOW: case AUDIT_OBJ_LEV_HIGH: |
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str = audit_unpack_string(&bufp, &remain, f->val); if (IS_ERR(str)) goto exit_free; entry->rule.buflen += f->val; |
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err = security_audit_rule_init(f->type, f->op, str, |
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(void **)&f->lsm_rule); |
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/* Keep currently invalid fields around in case they * become valid after a policy reload. */ if (err == -EINVAL) { |
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printk(KERN_WARNING "audit rule for LSM " |
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"\'%s\' is invalid ", str); err = 0; } if (err) { kfree(str); goto exit_free; } else |
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f->lsm_str = str; |
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break; |
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case AUDIT_WATCH: str = audit_unpack_string(&bufp, &remain, f->val); if (IS_ERR(str)) goto exit_free; entry->rule.buflen += f->val; err = audit_to_watch(&entry->rule, str, f->val, f->op); if (err) { kfree(str); goto exit_free; } break; |
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case AUDIT_DIR: str = audit_unpack_string(&bufp, &remain, f->val); if (IS_ERR(str)) goto exit_free; entry->rule.buflen += f->val; err = audit_make_tree(&entry->rule, str, f->op); kfree(str); if (err) goto exit_free; break; |
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case AUDIT_INODE: err = audit_to_inode(&entry->rule, f); if (err) goto exit_free; break; |
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case AUDIT_FILTERKEY: |
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if (entry->rule.filterkey || f->val > AUDIT_MAX_KEY_LEN) goto exit_free; str = audit_unpack_string(&bufp, &remain, f->val); if (IS_ERR(str)) goto exit_free; entry->rule.buflen += f->val; entry->rule.filterkey = str; break; |
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case AUDIT_PERM: if (f->val & ~15) goto exit_free; break; |
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case AUDIT_FILETYPE: |
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if (f->val & ~S_IFMT) |
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goto exit_free; break; |
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case AUDIT_FIELD_COMPARE: if (f->val > AUDIT_MAX_FIELD_COMPARE) goto exit_free; break; |
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default: goto exit_free; |
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} } |
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if (entry->rule.inode_f && entry->rule.inode_f->op == Audit_not_equal) entry->rule.inode_f = NULL; |
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exit_nofree: return entry; exit_free: audit_free_rule(entry); return ERR_PTR(err); } /* Pack a filter field's string representation into data block. */ |
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static inline size_t audit_pack_string(void **bufp, const char *str) |
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{ size_t len = strlen(str); memcpy(*bufp, str, len); *bufp += len; return len; } /* Translate kernel rule respresentation to struct audit_rule. * Exists for backward compatibility with userspace. */ static struct audit_rule *audit_krule_to_rule(struct audit_krule *krule) { struct audit_rule *rule; int i; |
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|
600 |
rule = kzalloc(sizeof(*rule), GFP_KERNEL); |
93315ed6d
|
601 |
if (unlikely(!rule)) |
0a3b483e8
|
602 |
return NULL; |
93315ed6d
|
603 604 605 606 607 608 609 610 611 |
rule->flags = krule->flags | krule->listnr; rule->action = krule->action; rule->field_count = krule->field_count; for (i = 0; i < rule->field_count; i++) { rule->values[i] = krule->fields[i].val; rule->fields[i] = krule->fields[i].type; if (krule->vers_ops == 1) { |
5af75d8d5
|
612 |
if (krule->fields[i].op == Audit_not_equal) |
93315ed6d
|
613 614 |
rule->fields[i] |= AUDIT_NEGATE; } else { |
5af75d8d5
|
615 |
rule->fields[i] |= audit_ops[krule->fields[i].op]; |
93315ed6d
|
616 617 618 619 620 621 |
} } for (i = 0; i < AUDIT_BITMASK_SIZE; i++) rule->mask[i] = krule->mask[i]; return rule; } |
fe7752bab
|
622 |
|
93315ed6d
|
623 624 625 626 627 628 629 630 631 |
/* Translate kernel rule respresentation to struct audit_rule_data. */ static struct audit_rule_data *audit_krule_to_data(struct audit_krule *krule) { struct audit_rule_data *data; void *bufp; int i; data = kmalloc(sizeof(*data) + krule->buflen, GFP_KERNEL); if (unlikely(!data)) |
0a3b483e8
|
632 |
return NULL; |
93315ed6d
|
633 634 635 636 637 638 639 640 641 642 |
memset(data, 0, sizeof(*data)); data->flags = krule->flags | krule->listnr; data->action = krule->action; data->field_count = krule->field_count; bufp = data->buf; for (i = 0; i < data->field_count; i++) { struct audit_field *f = &krule->fields[i]; data->fields[i] = f->type; |
5af75d8d5
|
643 |
data->fieldflags[i] = audit_ops[f->op]; |
93315ed6d
|
644 |
switch(f->type) { |
3a6b9f85c
|
645 646 647 648 649 |
case AUDIT_SUBJ_USER: case AUDIT_SUBJ_ROLE: case AUDIT_SUBJ_TYPE: case AUDIT_SUBJ_SEN: case AUDIT_SUBJ_CLR: |
6e5a2d1d3
|
650 651 652 653 654 |
case AUDIT_OBJ_USER: case AUDIT_OBJ_ROLE: case AUDIT_OBJ_TYPE: case AUDIT_OBJ_LEV_LOW: case AUDIT_OBJ_LEV_HIGH: |
3dc7e3153
|
655 |
data->buflen += data->values[i] = |
04305e4af
|
656 |
audit_pack_string(&bufp, f->lsm_str); |
3dc7e3153
|
657 |
break; |
f368c07d7
|
658 659 |
case AUDIT_WATCH: data->buflen += data->values[i] = |
cfcad62c7
|
660 661 |
audit_pack_string(&bufp, audit_watch_path(krule->watch)); |
f368c07d7
|
662 |
break; |
74c3cbe33
|
663 664 665 666 667 |
case AUDIT_DIR: data->buflen += data->values[i] = audit_pack_string(&bufp, audit_tree_path(krule->tree)); break; |
5adc8a6ad
|
668 669 670 671 |
case AUDIT_FILTERKEY: data->buflen += data->values[i] = audit_pack_string(&bufp, krule->filterkey); break; |
93315ed6d
|
672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 |
default: data->values[i] = f->val; } } for (i = 0; i < AUDIT_BITMASK_SIZE; i++) data->mask[i] = krule->mask[i]; return data; } /* Compare two rules in kernel format. Considered success if rules * don't match. */ static int audit_compare_rule(struct audit_krule *a, struct audit_krule *b) { int i; if (a->flags != b->flags || a->listnr != b->listnr || a->action != b->action || a->field_count != b->field_count) |
fe7752bab
|
691 692 693 |
return 1; for (i = 0; i < a->field_count; i++) { |
93315ed6d
|
694 695 |
if (a->fields[i].type != b->fields[i].type || a->fields[i].op != b->fields[i].op) |
fe7752bab
|
696 |
return 1; |
93315ed6d
|
697 698 |
switch(a->fields[i].type) { |
3a6b9f85c
|
699 700 701 702 703 |
case AUDIT_SUBJ_USER: case AUDIT_SUBJ_ROLE: case AUDIT_SUBJ_TYPE: case AUDIT_SUBJ_SEN: case AUDIT_SUBJ_CLR: |
6e5a2d1d3
|
704 705 706 707 708 |
case AUDIT_OBJ_USER: case AUDIT_OBJ_ROLE: case AUDIT_OBJ_TYPE: case AUDIT_OBJ_LEV_LOW: case AUDIT_OBJ_LEV_HIGH: |
04305e4af
|
709 |
if (strcmp(a->fields[i].lsm_str, b->fields[i].lsm_str)) |
3dc7e3153
|
710 711 |
return 1; break; |
f368c07d7
|
712 |
case AUDIT_WATCH: |
cfcad62c7
|
713 714 |
if (strcmp(audit_watch_path(a->watch), audit_watch_path(b->watch))) |
f368c07d7
|
715 716 |
return 1; break; |
74c3cbe33
|
717 718 719 720 721 |
case AUDIT_DIR: if (strcmp(audit_tree_path(a->tree), audit_tree_path(b->tree))) return 1; break; |
5adc8a6ad
|
722 723 724 725 726 |
case AUDIT_FILTERKEY: /* both filterkeys exist based on above type compare */ if (strcmp(a->filterkey, b->filterkey)) return 1; break; |
ca57ec0f0
|
727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 |
case AUDIT_UID: case AUDIT_EUID: case AUDIT_SUID: case AUDIT_FSUID: case AUDIT_LOGINUID: case AUDIT_OBJ_UID: if (!uid_eq(a->fields[i].uid, b->fields[i].uid)) return 1; break; case AUDIT_GID: case AUDIT_EGID: case AUDIT_SGID: case AUDIT_FSGID: case AUDIT_OBJ_GID: if (!gid_eq(a->fields[i].gid, b->fields[i].gid)) return 1; break; |
93315ed6d
|
744 745 746 747 |
default: if (a->fields[i].val != b->fields[i].val) return 1; } |
fe7752bab
|
748 749 750 751 752 753 754 755 |
} for (i = 0; i < AUDIT_BITMASK_SIZE; i++) if (a->mask[i] != b->mask[i]) return 1; return 0; } |
04305e4af
|
756 |
/* Duplicate LSM field information. The lsm_rule is opaque, so must be |
3dc7e3153
|
757 |
* re-initialized. */ |
d7a96f3a1
|
758 |
static inline int audit_dupe_lsm_field(struct audit_field *df, |
3dc7e3153
|
759 760 761 |
struct audit_field *sf) { int ret = 0; |
04305e4af
|
762 |
char *lsm_str; |
3dc7e3153
|
763 |
|
04305e4af
|
764 765 766 |
/* our own copy of lsm_str */ lsm_str = kstrdup(sf->lsm_str, GFP_KERNEL); if (unlikely(!lsm_str)) |
3e1fbd12c
|
767 |
return -ENOMEM; |
04305e4af
|
768 |
df->lsm_str = lsm_str; |
3dc7e3153
|
769 |
|
04305e4af
|
770 771 772 |
/* our own (refreshed) copy of lsm_rule */ ret = security_audit_rule_init(df->type, df->op, df->lsm_str, (void **)&df->lsm_rule); |
3dc7e3153
|
773 774 775 |
/* Keep currently invalid fields around in case they * become valid after a policy reload. */ if (ret == -EINVAL) { |
d7a96f3a1
|
776 |
printk(KERN_WARNING "audit rule for LSM \'%s\' is " |
04305e4af
|
777 778 |
"invalid ", df->lsm_str); |
3dc7e3153
|
779 780 781 782 783 784 785 |
ret = 0; } return ret; } /* Duplicate an audit rule. This will be a deep copy with the exception |
d7a96f3a1
|
786 |
* of the watch - that pointer is carried over. The LSM specific fields |
3dc7e3153
|
787 |
* will be updated in the copy. The point is to be able to replace the old |
f368c07d7
|
788 789 790 |
* rule with the new rule in the filterlist, then free the old rule. * The rlist element is undefined; list manipulations are handled apart from * the initial copy. */ |
ae7b8f410
|
791 |
struct audit_entry *audit_dupe_rule(struct audit_krule *old) |
3dc7e3153
|
792 793 794 795 |
{ u32 fcount = old->field_count; struct audit_entry *entry; struct audit_krule *new; |
5adc8a6ad
|
796 |
char *fk; |
3dc7e3153
|
797 798 799 800 801 802 803 804 805 806 807 808 809 |
int i, err = 0; entry = audit_init_entry(fcount); if (unlikely(!entry)) return ERR_PTR(-ENOMEM); new = &entry->rule; new->vers_ops = old->vers_ops; new->flags = old->flags; new->listnr = old->listnr; new->action = old->action; for (i = 0; i < AUDIT_BITMASK_SIZE; i++) new->mask[i] = old->mask[i]; |
0590b9335
|
810 |
new->prio = old->prio; |
3dc7e3153
|
811 |
new->buflen = old->buflen; |
f368c07d7
|
812 |
new->inode_f = old->inode_f; |
3dc7e3153
|
813 |
new->field_count = old->field_count; |
ae7b8f410
|
814 |
|
74c3cbe33
|
815 816 817 818 819 820 821 822 |
/* * note that we are OK with not refcounting here; audit_match_tree() * never dereferences tree and we can't get false positives there * since we'd have to have rule gone from the list *and* removed * before the chunks found by lookup had been allocated, i.e. before * the beginning of list scan. */ new->tree = old->tree; |
3dc7e3153
|
823 |
memcpy(new->fields, old->fields, sizeof(struct audit_field) * fcount); |
04305e4af
|
824 |
/* deep copy this information, updating the lsm_rule fields, because |
3dc7e3153
|
825 826 827 |
* the originals will all be freed when the old rule is freed. */ for (i = 0; i < fcount; i++) { switch (new->fields[i].type) { |
3a6b9f85c
|
828 829 830 831 832 |
case AUDIT_SUBJ_USER: case AUDIT_SUBJ_ROLE: case AUDIT_SUBJ_TYPE: case AUDIT_SUBJ_SEN: case AUDIT_SUBJ_CLR: |
6e5a2d1d3
|
833 834 835 836 837 |
case AUDIT_OBJ_USER: case AUDIT_OBJ_ROLE: case AUDIT_OBJ_TYPE: case AUDIT_OBJ_LEV_LOW: case AUDIT_OBJ_LEV_HIGH: |
d7a96f3a1
|
838 |
err = audit_dupe_lsm_field(&new->fields[i], |
3dc7e3153
|
839 |
&old->fields[i]); |
5adc8a6ad
|
840 841 842 843 844 845 846 |
break; case AUDIT_FILTERKEY: fk = kstrdup(old->filterkey, GFP_KERNEL); if (unlikely(!fk)) err = -ENOMEM; else new->filterkey = fk; |
3dc7e3153
|
847 848 849 850 851 852 |
} if (err) { audit_free_rule(entry); return ERR_PTR(err); } } |
ae7b8f410
|
853 854 855 |
if (old->watch) { audit_get_watch(old->watch); new->watch = old->watch; |
f368c07d7
|
856 |
} |
3dc7e3153
|
857 858 |
return entry; } |
f368c07d7
|
859 860 861 |
/* Find an existing audit rule. * Caller must hold audit_filter_mutex to prevent stale rule data. */ static struct audit_entry *audit_find_rule(struct audit_entry *entry, |
36c4f1b18
|
862 |
struct list_head **p) |
f368c07d7
|
863 864 |
{ struct audit_entry *e, *found = NULL; |
36c4f1b18
|
865 |
struct list_head *list; |
f368c07d7
|
866 |
int h; |
36c4f1b18
|
867 868 869 870 |
if (entry->rule.inode_f) { h = audit_hash_ino(entry->rule.inode_f->val); *p = list = &audit_inode_hash[h]; } else if (entry->rule.watch) { |
f368c07d7
|
871 872 873 874 875 876 877 878 879 880 |
/* we don't know the inode number, so must walk entire hash */ for (h = 0; h < AUDIT_INODE_BUCKETS; h++) { list = &audit_inode_hash[h]; list_for_each_entry(e, list, list) if (!audit_compare_rule(&entry->rule, &e->rule)) { found = e; goto out; } } goto out; |
36c4f1b18
|
881 882 |
} else { *p = list = &audit_filter_list[entry->rule.listnr]; |
f368c07d7
|
883 884 885 886 887 888 889 890 891 892 893 |
} list_for_each_entry(e, list, list) if (!audit_compare_rule(&entry->rule, &e->rule)) { found = e; goto out; } out: return found; } |
0590b9335
|
894 895 |
static u64 prio_low = ~0ULL/2; static u64 prio_high = ~0ULL/2 - 1; |
f368c07d7
|
896 |
/* Add rule to given filterlist if not a duplicate. */ |
36c4f1b18
|
897 |
static inline int audit_add_rule(struct audit_entry *entry) |
fe7752bab
|
898 |
{ |
93315ed6d
|
899 |
struct audit_entry *e; |
f368c07d7
|
900 |
struct audit_watch *watch = entry->rule.watch; |
74c3cbe33
|
901 |
struct audit_tree *tree = entry->rule.tree; |
36c4f1b18
|
902 |
struct list_head *list; |
ae7b8f410
|
903 |
int err; |
471a5c7c8
|
904 905 906 907 908 909 910 911 |
#ifdef CONFIG_AUDITSYSCALL int dont_count = 0; /* If either of these, don't count towards total */ if (entry->rule.listnr == AUDIT_FILTER_USER || entry->rule.listnr == AUDIT_FILTER_TYPE) dont_count = 1; #endif |
f368c07d7
|
912 |
|
f368c07d7
|
913 |
mutex_lock(&audit_filter_mutex); |
36c4f1b18
|
914 |
e = audit_find_rule(entry, &list); |
f368c07d7
|
915 |
if (e) { |
35fe4d0b1
|
916 |
mutex_unlock(&audit_filter_mutex); |
f368c07d7
|
917 |
err = -EEXIST; |
74c3cbe33
|
918 919 920 |
/* normally audit_add_tree_rule() will free it on failure */ if (tree) audit_put_tree(tree); |
f368c07d7
|
921 922 |
goto error; } |
fe7752bab
|
923 |
|
f368c07d7
|
924 925 |
if (watch) { /* audit_filter_mutex is dropped and re-taken during this call */ |
ae7b8f410
|
926 |
err = audit_add_watch(&entry->rule, &list); |
f368c07d7
|
927 928 929 930 |
if (err) { mutex_unlock(&audit_filter_mutex); goto error; } |
fe7752bab
|
931 |
} |
74c3cbe33
|
932 933 934 935 936 937 938 |
if (tree) { err = audit_add_tree_rule(&entry->rule); if (err) { mutex_unlock(&audit_filter_mutex); goto error; } } |
fe7752bab
|
939 |
|
0590b9335
|
940 941 942 943 944 945 946 |
entry->rule.prio = ~0ULL; if (entry->rule.listnr == AUDIT_FILTER_EXIT) { if (entry->rule.flags & AUDIT_FILTER_PREPEND) entry->rule.prio = ++prio_high; else entry->rule.prio = --prio_low; } |
fe7752bab
|
947 |
if (entry->rule.flags & AUDIT_FILTER_PREPEND) { |
e45aa212e
|
948 949 |
list_add(&entry->rule.list, &audit_rules_list[entry->rule.listnr]); |
fe7752bab
|
950 |
list_add_rcu(&entry->list, list); |
6a2bceec0
|
951 |
entry->rule.flags &= ~AUDIT_FILTER_PREPEND; |
fe7752bab
|
952 |
} else { |
e45aa212e
|
953 954 |
list_add_tail(&entry->rule.list, &audit_rules_list[entry->rule.listnr]); |
fe7752bab
|
955 956 |
list_add_tail_rcu(&entry->list, list); } |
471a5c7c8
|
957 958 959 |
#ifdef CONFIG_AUDITSYSCALL if (!dont_count) audit_n_rules++; |
e54dc2431
|
960 961 962 |
if (!audit_match_signal(entry)) audit_signals++; |
471a5c7c8
|
963 |
#endif |
f368c07d7
|
964 |
mutex_unlock(&audit_filter_mutex); |
fe7752bab
|
965 |
|
f368c07d7
|
966 967 968 |
return 0; error: |
f368c07d7
|
969 970 971 |
if (watch) audit_put_watch(watch); /* tmp watch, matches initial get */ return err; |
fe7752bab
|
972 |
} |
f368c07d7
|
973 |
/* Remove an existing rule from filterlist. */ |
36c4f1b18
|
974 |
static inline int audit_del_rule(struct audit_entry *entry) |
fe7752bab
|
975 976 |
{ struct audit_entry *e; |
cfcad62c7
|
977 |
struct audit_watch *watch = entry->rule.watch; |
74c3cbe33
|
978 |
struct audit_tree *tree = entry->rule.tree; |
36c4f1b18
|
979 |
struct list_head *list; |
36c4f1b18
|
980 |
int ret = 0; |
471a5c7c8
|
981 982 983 984 985 986 987 988 |
#ifdef CONFIG_AUDITSYSCALL int dont_count = 0; /* If either of these, don't count towards total */ if (entry->rule.listnr == AUDIT_FILTER_USER || entry->rule.listnr == AUDIT_FILTER_TYPE) dont_count = 1; #endif |
f368c07d7
|
989 |
|
f368c07d7
|
990 |
mutex_lock(&audit_filter_mutex); |
36c4f1b18
|
991 |
e = audit_find_rule(entry, &list); |
f368c07d7
|
992 993 994 995 996 |
if (!e) { mutex_unlock(&audit_filter_mutex); ret = -ENOENT; goto out; } |
cfcad62c7
|
997 |
if (e->rule.watch) |
a05fb6cc5
|
998 |
audit_remove_watch_rule(&e->rule); |
f368c07d7
|
999 |
|
74c3cbe33
|
1000 1001 |
if (e->rule.tree) audit_remove_tree_rule(&e->rule); |
f368c07d7
|
1002 |
list_del_rcu(&e->list); |
e45aa212e
|
1003 |
list_del(&e->rule.list); |
f368c07d7
|
1004 |
call_rcu(&e->rcu, audit_free_rule_rcu); |
471a5c7c8
|
1005 1006 1007 |
#ifdef CONFIG_AUDITSYSCALL if (!dont_count) audit_n_rules--; |
e54dc2431
|
1008 1009 1010 |
if (!audit_match_signal(entry)) audit_signals--; |
471a5c7c8
|
1011 |
#endif |
f368c07d7
|
1012 |
mutex_unlock(&audit_filter_mutex); |
f368c07d7
|
1013 |
out: |
cfcad62c7
|
1014 1015 |
if (watch) audit_put_watch(watch); /* match initial get */ |
74c3cbe33
|
1016 1017 |
if (tree) audit_put_tree(tree); /* that's the temporary one */ |
f368c07d7
|
1018 1019 |
return ret; |
fe7752bab
|
1020 |
} |
93315ed6d
|
1021 1022 |
/* List rules using struct audit_rule. Exists for backward * compatibility with userspace. */ |
9044e6bca
|
1023 |
static void audit_list(int pid, int seq, struct sk_buff_head *q) |
fe7752bab
|
1024 |
{ |
9044e6bca
|
1025 |
struct sk_buff *skb; |
e45aa212e
|
1026 |
struct audit_krule *r; |
fe7752bab
|
1027 |
int i; |
f368c07d7
|
1028 1029 |
/* This is a blocking read, so use audit_filter_mutex instead of rcu * iterator to sync with list writers. */ |
fe7752bab
|
1030 |
for (i=0; i<AUDIT_NR_FILTERS; i++) { |
e45aa212e
|
1031 |
list_for_each_entry(r, &audit_rules_list[i], list) { |
f368c07d7
|
1032 |
struct audit_rule *rule; |
e45aa212e
|
1033 |
rule = audit_krule_to_rule(r); |
f368c07d7
|
1034 1035 1036 1037 1038 1039 1040 1041 1042 |
if (unlikely(!rule)) break; skb = audit_make_reply(pid, seq, AUDIT_LIST, 0, 1, rule, sizeof(*rule)); if (skb) skb_queue_tail(q, skb); kfree(rule); } } |
9044e6bca
|
1043 1044 1045 |
skb = audit_make_reply(pid, seq, AUDIT_LIST, 1, 1, NULL, 0); if (skb) skb_queue_tail(q, skb); |
fe7752bab
|
1046 |
} |
93315ed6d
|
1047 |
/* List rules using struct audit_rule_data. */ |
9044e6bca
|
1048 |
static void audit_list_rules(int pid, int seq, struct sk_buff_head *q) |
93315ed6d
|
1049 |
{ |
9044e6bca
|
1050 |
struct sk_buff *skb; |
e45aa212e
|
1051 |
struct audit_krule *r; |
93315ed6d
|
1052 |
int i; |
f368c07d7
|
1053 1054 |
/* This is a blocking read, so use audit_filter_mutex instead of rcu * iterator to sync with list writers. */ |
93315ed6d
|
1055 |
for (i=0; i<AUDIT_NR_FILTERS; i++) { |
e45aa212e
|
1056 |
list_for_each_entry(r, &audit_rules_list[i], list) { |
f368c07d7
|
1057 |
struct audit_rule_data *data; |
e45aa212e
|
1058 |
data = audit_krule_to_data(r); |
f368c07d7
|
1059 1060 1061 1062 |
if (unlikely(!data)) break; skb = audit_make_reply(pid, seq, AUDIT_LIST_RULES, 0, 1, data, sizeof(*data) + data->buflen); |
9044e6bca
|
1063 1064 |
if (skb) skb_queue_tail(q, skb); |
93315ed6d
|
1065 1066 1067 |
kfree(data); } } |
9044e6bca
|
1068 1069 1070 |
skb = audit_make_reply(pid, seq, AUDIT_LIST_RULES, 1, 1, NULL, 0); if (skb) skb_queue_tail(q, skb); |
93315ed6d
|
1071 |
} |
5adc8a6ad
|
1072 |
/* Log rule additions and removals */ |
e1760bd5f
|
1073 |
static void audit_log_rule_change(kuid_t loginuid, u32 sessionid, u32 sid, |
2532386f4
|
1074 1075 |
char *action, struct audit_krule *rule, int res) |
5adc8a6ad
|
1076 1077 |
{ struct audit_buffer *ab; |
1a6b9f231
|
1078 1079 |
if (!audit_enabled) return; |
5adc8a6ad
|
1080 1081 1082 |
ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE); if (!ab) return; |
e1760bd5f
|
1083 1084 |
audit_log_format(ab, "auid=%u ses=%u", from_kuid(&init_user_ns, loginuid), sessionid); |
5adc8a6ad
|
1085 1086 1087 |
if (sid) { char *ctx = NULL; u32 len; |
2a862b32f
|
1088 |
if (security_secid_to_secctx(sid, &ctx, &len)) |
5adc8a6ad
|
1089 |
audit_log_format(ab, " ssid=%u", sid); |
2a862b32f
|
1090 |
else { |
5adc8a6ad
|
1091 |
audit_log_format(ab, " subj=%s", ctx); |
2a862b32f
|
1092 1093 |
security_release_secctx(ctx, len); } |
5adc8a6ad
|
1094 |
} |
9d9609851
|
1095 1096 1097 |
audit_log_format(ab, " op="); audit_log_string(ab, action); audit_log_key(ab, rule->filterkey); |
5adc8a6ad
|
1098 1099 1100 |
audit_log_format(ab, " list=%d res=%d", rule->listnr, res); audit_log_end(ab); } |
fe7752bab
|
1101 1102 1103 1104 1105 1106 1107 |
/** * audit_receive_filter - apply all rules to the specified message type * @type: audit message type * @pid: target pid for netlink audit messages * @uid: target uid for netlink audit messages * @seq: netlink audit message sequence (serial) number * @data: payload data |
93315ed6d
|
1108 |
* @datasz: size of payload data |
fe7752bab
|
1109 |
* @loginuid: loginuid of sender |
9f0aecdd1
|
1110 |
* @sessionid: sessionid for netlink audit message |
ce29b682e
|
1111 |
* @sid: SE Linux Security ID of sender |
fe7752bab
|
1112 |
*/ |
017143fec
|
1113 |
int audit_receive_filter(int type, int pid, int seq, void *data, |
e1760bd5f
|
1114 |
size_t datasz, kuid_t loginuid, u32 sessionid, u32 sid) |
fe7752bab
|
1115 1116 |
{ struct task_struct *tsk; |
9044e6bca
|
1117 |
struct audit_netlink_list *dest; |
93315ed6d
|
1118 1119 |
int err = 0; struct audit_entry *entry; |
fe7752bab
|
1120 1121 1122 |
switch (type) { case AUDIT_LIST: |
93315ed6d
|
1123 |
case AUDIT_LIST_RULES: |
fe7752bab
|
1124 1125 1126 1127 1128 |
/* We can't just spew out the rules here because we might fill * the available socket buffer space and deadlock waiting for * auditctl to read from it... which isn't ever going to * happen if we're actually running in the context of auditctl * trying to _send_ the stuff */ |
9ce34218a
|
1129 |
|
9044e6bca
|
1130 |
dest = kmalloc(sizeof(struct audit_netlink_list), GFP_KERNEL); |
fe7752bab
|
1131 1132 |
if (!dest) return -ENOMEM; |
9044e6bca
|
1133 1134 |
dest->pid = pid; skb_queue_head_init(&dest->q); |
fe7752bab
|
1135 |
|
f368c07d7
|
1136 |
mutex_lock(&audit_filter_mutex); |
93315ed6d
|
1137 |
if (type == AUDIT_LIST) |
9044e6bca
|
1138 |
audit_list(pid, seq, &dest->q); |
93315ed6d
|
1139 |
else |
9044e6bca
|
1140 |
audit_list_rules(pid, seq, &dest->q); |
f368c07d7
|
1141 |
mutex_unlock(&audit_filter_mutex); |
9044e6bca
|
1142 1143 |
tsk = kthread_run(audit_send_list, dest, "audit_send_list"); |
fe7752bab
|
1144 |
if (IS_ERR(tsk)) { |
9044e6bca
|
1145 |
skb_queue_purge(&dest->q); |
fe7752bab
|
1146 1147 1148 1149 1150 |
kfree(dest); err = PTR_ERR(tsk); } break; case AUDIT_ADD: |
93315ed6d
|
1151 1152 1153 1154 1155 1156 1157 |
case AUDIT_ADD_RULE: if (type == AUDIT_ADD) entry = audit_rule_to_entry(data); else entry = audit_data_to_entry(data, datasz); if (IS_ERR(entry)) return PTR_ERR(entry); |
36c4f1b18
|
1158 |
err = audit_add_rule(entry); |
9d9609851
|
1159 |
audit_log_rule_change(loginuid, sessionid, sid, "add rule", |
2532386f4
|
1160 |
&entry->rule, !err); |
5d3301088
|
1161 1162 |
if (err) |
93315ed6d
|
1163 |
audit_free_rule(entry); |
fe7752bab
|
1164 1165 |
break; case AUDIT_DEL: |
93315ed6d
|
1166 1167 1168 1169 1170 1171 1172 |
case AUDIT_DEL_RULE: if (type == AUDIT_DEL) entry = audit_rule_to_entry(data); else entry = audit_data_to_entry(data, datasz); if (IS_ERR(entry)) return PTR_ERR(entry); |
36c4f1b18
|
1173 |
err = audit_del_rule(entry); |
9d9609851
|
1174 |
audit_log_rule_change(loginuid, sessionid, sid, "remove rule", |
2532386f4
|
1175 |
&entry->rule, !err); |
5d3301088
|
1176 |
|
93315ed6d
|
1177 |
audit_free_rule(entry); |
fe7752bab
|
1178 1179 1180 1181 1182 1183 1184 |
break; default: return -EINVAL; } return err; } |
5af75d8d5
|
1185 |
int audit_comparator(u32 left, u32 op, u32 right) |
fe7752bab
|
1186 1187 |
{ switch (op) { |
5af75d8d5
|
1188 |
case Audit_equal: |
fe7752bab
|
1189 |
return (left == right); |
5af75d8d5
|
1190 |
case Audit_not_equal: |
fe7752bab
|
1191 |
return (left != right); |
5af75d8d5
|
1192 |
case Audit_lt: |
fe7752bab
|
1193 |
return (left < right); |
5af75d8d5
|
1194 |
case Audit_le: |
fe7752bab
|
1195 |
return (left <= right); |
5af75d8d5
|
1196 |
case Audit_gt: |
fe7752bab
|
1197 |
return (left > right); |
5af75d8d5
|
1198 |
case Audit_ge: |
fe7752bab
|
1199 |
return (left >= right); |
5af75d8d5
|
1200 |
case Audit_bitmask: |
74f2345b6
|
1201 |
return (left & right); |
5af75d8d5
|
1202 |
case Audit_bittest: |
74f2345b6
|
1203 |
return ((left & right) == right); |
5af75d8d5
|
1204 1205 1206 |
default: BUG(); return 0; |
fe7752bab
|
1207 1208 |
} } |
ca57ec0f0
|
1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 |
int audit_uid_comparator(kuid_t left, u32 op, kuid_t right) { switch (op) { case Audit_equal: return uid_eq(left, right); case Audit_not_equal: return !uid_eq(left, right); case Audit_lt: return uid_lt(left, right); case Audit_le: return uid_lte(left, right); case Audit_gt: return uid_gt(left, right); case Audit_ge: return uid_gte(left, right); case Audit_bitmask: case Audit_bittest: default: BUG(); return 0; } } int audit_gid_comparator(kgid_t left, u32 op, kgid_t right) { switch (op) { case Audit_equal: return gid_eq(left, right); case Audit_not_equal: return !gid_eq(left, right); case Audit_lt: return gid_lt(left, right); case Audit_le: return gid_lte(left, right); case Audit_gt: return gid_gt(left, right); case Audit_ge: return gid_gte(left, right); case Audit_bitmask: case Audit_bittest: default: BUG(); return 0; } } |
bfcec7087
|
1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 |
/** * parent_len - find the length of the parent portion of a pathname * @path: pathname of which to determine length */ int parent_len(const char *path) { int plen; const char *p; plen = strlen(path); if (plen == 0) return plen; /* disregard trailing slashes */ p = path + plen - 1; while ((*p == '/') && (p > path)) p--; /* walk backward until we find the next slash or hit beginning */ while ((*p != '/') && (p > path)) p--; /* did we find a slash? Then increment to include it in path */ if (*p == '/') p++; return p - path; } |
e3d6b07b8
|
1283 1284 1285 1286 1287 1288 1289 1290 1291 |
/** * audit_compare_dname_path - compare given dentry name with last component in * given path. Return of 0 indicates a match. * @dname: dentry name that we're comparing * @path: full pathname that we're comparing * @parentlen: length of the parent if known. Passing in AUDIT_NAME_FULL * here indicates that we must compute this value. */ int audit_compare_dname_path(const char *dname, const char *path, int parentlen) |
f368c07d7
|
1292 |
{ |
e3d6b07b8
|
1293 |
int dlen, pathlen; |
f368c07d7
|
1294 |
const char *p; |
f368c07d7
|
1295 |
dlen = strlen(dname); |
29e9a3467
|
1296 1297 |
pathlen = strlen(path); if (pathlen < dlen) |
f368c07d7
|
1298 |
return 1; |
e3d6b07b8
|
1299 |
parentlen = parentlen == AUDIT_NAME_FULL ? parent_len(path) : parentlen; |
29e9a3467
|
1300 |
if (pathlen - parentlen != dlen) |
f368c07d7
|
1301 |
return 1; |
29e9a3467
|
1302 1303 |
p = path + parentlen; |
fe7752bab
|
1304 |
|
f368c07d7
|
1305 1306 |
return strncmp(p, dname, dlen); } |
fe7752bab
|
1307 |
|
02276bda4
|
1308 |
static int audit_filter_user_rules(struct audit_krule *rule, |
fe7752bab
|
1309 1310 1311 1312 1313 |
enum audit_state *state) { int i; for (i = 0; i < rule->field_count; i++) { |
93315ed6d
|
1314 |
struct audit_field *f = &rule->fields[i]; |
fe7752bab
|
1315 |
int result = 0; |
c53fa1ed9
|
1316 |
u32 sid; |
fe7752bab
|
1317 |
|
93315ed6d
|
1318 |
switch (f->type) { |
fe7752bab
|
1319 |
case AUDIT_PID: |
02276bda4
|
1320 |
result = audit_comparator(task_pid_vnr(current), f->op, f->val); |
fe7752bab
|
1321 1322 |
break; case AUDIT_UID: |
ca57ec0f0
|
1323 |
result = audit_uid_comparator(current_uid(), f->op, f->uid); |
fe7752bab
|
1324 1325 |
break; case AUDIT_GID: |
ca57ec0f0
|
1326 |
result = audit_gid_comparator(current_gid(), f->op, f->gid); |
fe7752bab
|
1327 1328 |
break; case AUDIT_LOGINUID: |
ca57ec0f0
|
1329 1330 |
result = audit_uid_comparator(audit_get_loginuid(current), f->op, f->uid); |
fe7752bab
|
1331 |
break; |
d29be158a
|
1332 1333 1334 1335 1336 |
case AUDIT_SUBJ_USER: case AUDIT_SUBJ_ROLE: case AUDIT_SUBJ_TYPE: case AUDIT_SUBJ_SEN: case AUDIT_SUBJ_CLR: |
c53fa1ed9
|
1337 1338 1339 |
if (f->lsm_rule) { security_task_getsecid(current, &sid); result = security_audit_rule_match(sid, |
d29be158a
|
1340 1341 1342 1343 |
f->type, f->op, f->lsm_rule, NULL); |
c53fa1ed9
|
1344 |
} |
d29be158a
|
1345 |
break; |
fe7752bab
|
1346 1347 1348 1349 1350 1351 1352 |
} if (!result) return 0; } switch (rule->action) { case AUDIT_NEVER: *state = AUDIT_DISABLED; break; |
fe7752bab
|
1353 1354 1355 1356 |
case AUDIT_ALWAYS: *state = AUDIT_RECORD_CONTEXT; break; } return 1; } |
02276bda4
|
1357 |
int audit_filter_user(void) |
fe7752bab
|
1358 |
{ |
11f57cedc
|
1359 |
enum audit_state state = AUDIT_DISABLED; |
fe7752bab
|
1360 |
struct audit_entry *e; |
fe7752bab
|
1361 1362 1363 1364 |
int ret = 1; rcu_read_lock(); list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_USER], list) { |
02276bda4
|
1365 |
if (audit_filter_user_rules(&e->rule, &state)) { |
fe7752bab
|
1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 |
if (state == AUDIT_DISABLED) ret = 0; break; } } rcu_read_unlock(); return ret; /* Audit by default */ } int audit_filter_type(int type) { struct audit_entry *e; int result = 0; |
9ce34218a
|
1380 |
|
fe7752bab
|
1381 1382 1383 1384 1385 1386 |
rcu_read_lock(); if (list_empty(&audit_filter_list[AUDIT_FILTER_TYPE])) goto unlock_and_return; list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TYPE], list) { |
fe7752bab
|
1387 |
int i; |
93315ed6d
|
1388 1389 1390 1391 |
for (i = 0; i < e->rule.field_count; i++) { struct audit_field *f = &e->rule.fields[i]; if (f->type == AUDIT_MSGTYPE) { result = audit_comparator(type, f->op, f->val); |
fe7752bab
|
1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 |
if (!result) break; } } if (result) goto unlock_and_return; } unlock_and_return: rcu_read_unlock(); return result; } |
3dc7e3153
|
1403 |
|
e45aa212e
|
1404 |
static int update_lsm_rule(struct audit_krule *r) |
1a9d0797b
|
1405 |
{ |
e45aa212e
|
1406 |
struct audit_entry *entry = container_of(r, struct audit_entry, rule); |
1a9d0797b
|
1407 |
struct audit_entry *nentry; |
1a9d0797b
|
1408 |
int err = 0; |
e45aa212e
|
1409 |
if (!security_audit_rule_known(r)) |
1a9d0797b
|
1410 |
return 0; |
ae7b8f410
|
1411 |
nentry = audit_dupe_rule(r); |
1a9d0797b
|
1412 1413 1414 1415 1416 |
if (IS_ERR(nentry)) { /* save the first error encountered for the * return value */ err = PTR_ERR(nentry); audit_panic("error updating LSM filters"); |
ae7b8f410
|
1417 |
if (r->watch) |
e45aa212e
|
1418 |
list_del(&r->rlist); |
1a9d0797b
|
1419 |
list_del_rcu(&entry->list); |
e45aa212e
|
1420 |
list_del(&r->list); |
1a9d0797b
|
1421 |
} else { |
ae7b8f410
|
1422 |
if (r->watch || r->tree) |
e45aa212e
|
1423 |
list_replace_init(&r->rlist, &nentry->rule.rlist); |
1a9d0797b
|
1424 |
list_replace_rcu(&entry->list, &nentry->list); |
e45aa212e
|
1425 |
list_replace(&r->list, &nentry->rule.list); |
1a9d0797b
|
1426 1427 1428 1429 1430 |
} call_rcu(&entry->rcu, audit_free_rule_rcu); return err; } |
04305e4af
|
1431 |
/* This function will re-initialize the lsm_rule field of all applicable rules. |
d7a96f3a1
|
1432 |
* It will traverse the filter lists serarching for rules that contain LSM |
3dc7e3153
|
1433 |
* specific filter fields. When such a rule is found, it is copied, the |
d7a96f3a1
|
1434 |
* LSM field is re-initialized, and the old rule is replaced with the |
3dc7e3153
|
1435 |
* updated rule. */ |
d7a96f3a1
|
1436 |
int audit_update_lsm_rules(void) |
3dc7e3153
|
1437 |
{ |
e45aa212e
|
1438 |
struct audit_krule *r, *n; |
3dc7e3153
|
1439 |
int i, err = 0; |
f368c07d7
|
1440 1441 |
/* audit_filter_mutex synchronizes the writers */ mutex_lock(&audit_filter_mutex); |
3dc7e3153
|
1442 1443 |
for (i = 0; i < AUDIT_NR_FILTERS; i++) { |
e45aa212e
|
1444 1445 |
list_for_each_entry_safe(r, n, &audit_rules_list[i], list) { int res = update_lsm_rule(r); |
1a9d0797b
|
1446 1447 |
if (!err) err = res; |
3dc7e3153
|
1448 1449 |
} } |
f368c07d7
|
1450 |
mutex_unlock(&audit_filter_mutex); |
3dc7e3153
|
1451 1452 1453 |
return err; } |