| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * AppArmor security module |
| * |
| * This file contains AppArmor functions for unpacking policy loaded from |
| * userspace. |
| * |
| * Copyright (C) 1998-2008 Novell/SUSE |
| * Copyright 2009-2010 Canonical Ltd. |
| * |
| * AppArmor uses a serialized binary format for loading policy. To find |
| * policy format documentation see Documentation/admin-guide/LSM/apparmor.rst |
| * All policy is validated before it is used. |
| */ |
| |
| #include <asm/unaligned.h> |
| #include <kunit/visibility.h> |
| #include <linux/ctype.h> |
| #include <linux/errno.h> |
| #include <linux/zstd.h> |
| |
| #include "include/apparmor.h" |
| #include "include/audit.h" |
| #include "include/cred.h" |
| #include "include/crypto.h" |
| #include "include/file.h" |
| #include "include/match.h" |
| #include "include/path.h" |
| #include "include/policy.h" |
| #include "include/policy_unpack.h" |
| #include "include/policy_compat.h" |
| |
| /* audit callback for unpack fields */ |
| static void audit_cb(struct audit_buffer *ab, void *va) |
| { |
| struct common_audit_data *sa = va; |
| |
| if (aad(sa)->iface.ns) { |
| audit_log_format(ab, " ns="); |
| audit_log_untrustedstring(ab, aad(sa)->iface.ns); |
| } |
| if (aad(sa)->name) { |
| audit_log_format(ab, " name="); |
| audit_log_untrustedstring(ab, aad(sa)->name); |
| } |
| if (aad(sa)->iface.pos) |
| audit_log_format(ab, " offset=%ld", aad(sa)->iface.pos); |
| } |
| |
| /** |
| * audit_iface - do audit message for policy unpacking/load/replace/remove |
| * @new: profile if it has been allocated (MAYBE NULL) |
| * @ns_name: name of the ns the profile is to be loaded to (MAY BE NULL) |
| * @name: name of the profile being manipulated (MAYBE NULL) |
| * @info: any extra info about the failure (MAYBE NULL) |
| * @e: buffer position info |
| * @error: error code |
| * |
| * Returns: %0 or error |
| */ |
| static int audit_iface(struct aa_profile *new, const char *ns_name, |
| const char *name, const char *info, struct aa_ext *e, |
| int error) |
| { |
| struct aa_profile *profile = labels_profile(aa_current_raw_label()); |
| DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, AA_CLASS_NONE, NULL); |
| if (e) |
| aad(&sa)->iface.pos = e->pos - e->start; |
| aad(&sa)->iface.ns = ns_name; |
| if (new) |
| aad(&sa)->name = new->base.hname; |
| else |
| aad(&sa)->name = name; |
| aad(&sa)->info = info; |
| aad(&sa)->error = error; |
| |
| return aa_audit(AUDIT_APPARMOR_STATUS, profile, &sa, audit_cb); |
| } |
| |
| void __aa_loaddata_update(struct aa_loaddata *data, long revision) |
| { |
| AA_BUG(!data); |
| AA_BUG(!data->ns); |
| AA_BUG(!mutex_is_locked(&data->ns->lock)); |
| AA_BUG(data->revision > revision); |
| |
| data->revision = revision; |
| if ((data->dents[AAFS_LOADDATA_REVISION])) { |
| d_inode(data->dents[AAFS_LOADDATA_DIR])->i_mtime = |
| current_time(d_inode(data->dents[AAFS_LOADDATA_DIR])); |
| d_inode(data->dents[AAFS_LOADDATA_REVISION])->i_mtime = |
| current_time(d_inode(data->dents[AAFS_LOADDATA_REVISION])); |
| } |
| } |
| |
| bool aa_rawdata_eq(struct aa_loaddata *l, struct aa_loaddata *r) |
| { |
| if (l->size != r->size) |
| return false; |
| if (l->compressed_size != r->compressed_size) |
| return false; |
| if (aa_g_hash_policy && memcmp(l->hash, r->hash, aa_hash_size()) != 0) |
| return false; |
| return memcmp(l->data, r->data, r->compressed_size ?: r->size) == 0; |
| } |
| |
| /* |
| * need to take the ns mutex lock which is NOT safe most places that |
| * put_loaddata is called, so we have to delay freeing it |
| */ |
| static void do_loaddata_free(struct work_struct *work) |
| { |
| struct aa_loaddata *d = container_of(work, struct aa_loaddata, work); |
| struct aa_ns *ns = aa_get_ns(d->ns); |
| |
| if (ns) { |
| mutex_lock_nested(&ns->lock, ns->level); |
| __aa_fs_remove_rawdata(d); |
| mutex_unlock(&ns->lock); |
| aa_put_ns(ns); |
| } |
| |
| kfree_sensitive(d->hash); |
| kfree_sensitive(d->name); |
| kvfree(d->data); |
| kfree_sensitive(d); |
| } |
| |
| void aa_loaddata_kref(struct kref *kref) |
| { |
| struct aa_loaddata *d = container_of(kref, struct aa_loaddata, count); |
| |
| if (d) { |
| INIT_WORK(&d->work, do_loaddata_free); |
| schedule_work(&d->work); |
| } |
| } |
| |
| struct aa_loaddata *aa_loaddata_alloc(size_t size) |
| { |
| struct aa_loaddata *d; |
| |
| d = kzalloc(sizeof(*d), GFP_KERNEL); |
| if (d == NULL) |
| return ERR_PTR(-ENOMEM); |
| d->data = kvzalloc(size, GFP_KERNEL); |
| if (!d->data) { |
| kfree(d); |
| return ERR_PTR(-ENOMEM); |
| } |
| kref_init(&d->count); |
| INIT_LIST_HEAD(&d->list); |
| |
| return d; |
| } |
| |
| /* test if read will be in packed data bounds */ |
| VISIBLE_IF_KUNIT bool aa_inbounds(struct aa_ext *e, size_t size) |
| { |
| return (size <= e->end - e->pos); |
| } |
| EXPORT_SYMBOL_IF_KUNIT(aa_inbounds); |
| |
| static void *kvmemdup(const void *src, size_t len) |
| { |
| void *p = kvmalloc(len, GFP_KERNEL); |
| |
| if (p) |
| memcpy(p, src, len); |
| return p; |
| } |
| |
| /** |
| * aa_unpack_u16_chunk - test and do bounds checking for a u16 size based chunk |
| * @e: serialized data read head (NOT NULL) |
| * @chunk: start address for chunk of data (NOT NULL) |
| * |
| * Returns: the size of chunk found with the read head at the end of the chunk. |
| */ |
| VISIBLE_IF_KUNIT size_t aa_unpack_u16_chunk(struct aa_ext *e, char **chunk) |
| { |
| size_t size = 0; |
| void *pos = e->pos; |
| |
| if (!aa_inbounds(e, sizeof(u16))) |
| goto fail; |
| size = le16_to_cpu(get_unaligned((__le16 *) e->pos)); |
| e->pos += sizeof(__le16); |
| if (!aa_inbounds(e, size)) |
| goto fail; |
| *chunk = e->pos; |
| e->pos += size; |
| return size; |
| |
| fail: |
| e->pos = pos; |
| return 0; |
| } |
| EXPORT_SYMBOL_IF_KUNIT(aa_unpack_u16_chunk); |
| |
| /* unpack control byte */ |
| VISIBLE_IF_KUNIT bool aa_unpack_X(struct aa_ext *e, enum aa_code code) |
| { |
| if (!aa_inbounds(e, 1)) |
| return false; |
| if (*(u8 *) e->pos != code) |
| return false; |
| e->pos++; |
| return true; |
| } |
| EXPORT_SYMBOL_IF_KUNIT(aa_unpack_X); |
| |
| /** |
| * aa_unpack_nameX - check is the next element is of type X with a name of @name |
| * @e: serialized data extent information (NOT NULL) |
| * @code: type code |
| * @name: name to match to the serialized element. (MAYBE NULL) |
| * |
| * check that the next serialized data element is of type X and has a tag |
| * name @name. If @name is specified then there must be a matching |
| * name element in the stream. If @name is NULL any name element will be |
| * skipped and only the typecode will be tested. |
| * |
| * Returns true on success (both type code and name tests match) and the read |
| * head is advanced past the headers |
| * |
| * Returns: false if either match fails, the read head does not move |
| */ |
| VISIBLE_IF_KUNIT bool aa_unpack_nameX(struct aa_ext *e, enum aa_code code, const char *name) |
| { |
| /* |
| * May need to reset pos if name or type doesn't match |
| */ |
| void *pos = e->pos; |
| /* |
| * Check for presence of a tagname, and if present name size |
| * AA_NAME tag value is a u16. |
| */ |
| if (aa_unpack_X(e, AA_NAME)) { |
| char *tag = NULL; |
| size_t size = aa_unpack_u16_chunk(e, &tag); |
| /* if a name is specified it must match. otherwise skip tag */ |
| if (name && (!size || tag[size-1] != '\0' || strcmp(name, tag))) |
| goto fail; |
| } else if (name) { |
| /* if a name is specified and there is no name tag fail */ |
| goto fail; |
| } |
| |
| /* now check if type code matches */ |
| if (aa_unpack_X(e, code)) |
| return true; |
| |
| fail: |
| e->pos = pos; |
| return false; |
| } |
| EXPORT_SYMBOL_IF_KUNIT(aa_unpack_nameX); |
| |
| static bool unpack_u8(struct aa_ext *e, u8 *data, const char *name) |
| { |
| void *pos = e->pos; |
| |
| if (aa_unpack_nameX(e, AA_U8, name)) { |
| if (!aa_inbounds(e, sizeof(u8))) |
| goto fail; |
| if (data) |
| *data = *((u8 *)e->pos); |
| e->pos += sizeof(u8); |
| return true; |
| } |
| |
| fail: |
| e->pos = pos; |
| return false; |
| } |
| |
| VISIBLE_IF_KUNIT bool aa_unpack_u32(struct aa_ext *e, u32 *data, const char *name) |
| { |
| void *pos = e->pos; |
| |
| if (aa_unpack_nameX(e, AA_U32, name)) { |
| if (!aa_inbounds(e, sizeof(u32))) |
| goto fail; |
| if (data) |
| *data = le32_to_cpu(get_unaligned((__le32 *) e->pos)); |
| e->pos += sizeof(u32); |
| return true; |
| } |
| |
| fail: |
| e->pos = pos; |
| return false; |
| } |
| EXPORT_SYMBOL_IF_KUNIT(aa_unpack_u32); |
| |
| VISIBLE_IF_KUNIT bool aa_unpack_u64(struct aa_ext *e, u64 *data, const char *name) |
| { |
| void *pos = e->pos; |
| |
| if (aa_unpack_nameX(e, AA_U64, name)) { |
| if (!aa_inbounds(e, sizeof(u64))) |
| goto fail; |
| if (data) |
| *data = le64_to_cpu(get_unaligned((__le64 *) e->pos)); |
| e->pos += sizeof(u64); |
| return true; |
| } |
| |
| fail: |
| e->pos = pos; |
| return false; |
| } |
| EXPORT_SYMBOL_IF_KUNIT(aa_unpack_u64); |
| |
| VISIBLE_IF_KUNIT bool aa_unpack_array(struct aa_ext *e, const char *name, u16 *size) |
| { |
| void *pos = e->pos; |
| |
| if (aa_unpack_nameX(e, AA_ARRAY, name)) { |
| if (!aa_inbounds(e, sizeof(u16))) |
| goto fail; |
| *size = le16_to_cpu(get_unaligned((__le16 *) e->pos)); |
| e->pos += sizeof(u16); |
| return true; |
| } |
| |
| fail: |
| e->pos = pos; |
| return false; |
| } |
| EXPORT_SYMBOL_IF_KUNIT(aa_unpack_array); |
| |
| VISIBLE_IF_KUNIT size_t aa_unpack_blob(struct aa_ext *e, char **blob, const char *name) |
| { |
| void *pos = e->pos; |
| |
| if (aa_unpack_nameX(e, AA_BLOB, name)) { |
| u32 size; |
| if (!aa_inbounds(e, sizeof(u32))) |
| goto fail; |
| size = le32_to_cpu(get_unaligned((__le32 *) e->pos)); |
| e->pos += sizeof(u32); |
| if (aa_inbounds(e, (size_t) size)) { |
| *blob = e->pos; |
| e->pos += size; |
| return size; |
| } |
| } |
| |
| fail: |
| e->pos = pos; |
| return 0; |
| } |
| EXPORT_SYMBOL_IF_KUNIT(aa_unpack_blob); |
| |
| VISIBLE_IF_KUNIT int aa_unpack_str(struct aa_ext *e, const char **string, const char *name) |
| { |
| char *src_str; |
| size_t size = 0; |
| void *pos = e->pos; |
| *string = NULL; |
| if (aa_unpack_nameX(e, AA_STRING, name)) { |
| size = aa_unpack_u16_chunk(e, &src_str); |
| if (size) { |
| /* strings are null terminated, length is size - 1 */ |
| if (src_str[size - 1] != 0) |
| goto fail; |
| *string = src_str; |
| |
| return size; |
| } |
| } |
| |
| fail: |
| e->pos = pos; |
| return 0; |
| } |
| EXPORT_SYMBOL_IF_KUNIT(aa_unpack_str); |
| |
| VISIBLE_IF_KUNIT int aa_unpack_strdup(struct aa_ext *e, char **string, const char *name) |
| { |
| const char *tmp; |
| void *pos = e->pos; |
| int res = aa_unpack_str(e, &tmp, name); |
| *string = NULL; |
| |
| if (!res) |
| return 0; |
| |
| *string = kmemdup(tmp, res, GFP_KERNEL); |
| if (!*string) { |
| e->pos = pos; |
| return 0; |
| } |
| |
| return res; |
| } |
| EXPORT_SYMBOL_IF_KUNIT(aa_unpack_strdup); |
| |
| |
| /** |
| * unpack_dfa - unpack a file rule dfa |
| * @e: serialized data extent information (NOT NULL) |
| * @flags: dfa flags to check |
| * |
| * returns dfa or ERR_PTR or NULL if no dfa |
| */ |
| static struct aa_dfa *unpack_dfa(struct aa_ext *e, int flags) |
| { |
| char *blob = NULL; |
| size_t size; |
| struct aa_dfa *dfa = NULL; |
| |
| size = aa_unpack_blob(e, &blob, "aadfa"); |
| if (size) { |
| /* |
| * The dfa is aligned with in the blob to 8 bytes |
| * from the beginning of the stream. |
| * alignment adjust needed by dfa unpack |
| */ |
| size_t sz = blob - (char *) e->start - |
| ((e->pos - e->start) & 7); |
| size_t pad = ALIGN(sz, 8) - sz; |
| if (aa_g_paranoid_load) |
| flags |= DFA_FLAG_VERIFY_STATES; |
| dfa = aa_dfa_unpack(blob + pad, size - pad, flags); |
| |
| if (IS_ERR(dfa)) |
| return dfa; |
| |
| } |
| |
| return dfa; |
| } |
| |
| /** |
| * unpack_trans_table - unpack a profile transition table |
| * @e: serialized data extent information (NOT NULL) |
| * @table: str table to unpack to (NOT NULL) |
| * |
| * Returns: true if table successfully unpacked or not present |
| */ |
| static bool unpack_trans_table(struct aa_ext *e, struct aa_str_table *strs) |
| { |
| void *saved_pos = e->pos; |
| char **table = NULL; |
| |
| /* exec table is optional */ |
| if (aa_unpack_nameX(e, AA_STRUCT, "xtable")) { |
| u16 size; |
| int i; |
| |
| if (!aa_unpack_array(e, NULL, &size)) |
| /* |
| * Note: index into trans table array is a max |
| * of 2^24, but unpack array can only unpack |
| * an array of 2^16 in size atm so no need |
| * for size check here |
| */ |
| goto fail; |
| table = kcalloc(size, sizeof(char *), GFP_KERNEL); |
| if (!table) |
| goto fail; |
| |
| for (i = 0; i < size; i++) { |
| char *str; |
| int c, j, pos, size2 = aa_unpack_strdup(e, &str, NULL); |
| /* aa_unpack_strdup verifies that the last character is |
| * null termination byte. |
| */ |
| if (!size2) |
| goto fail; |
| table[i] = str; |
| /* verify that name doesn't start with space */ |
| if (isspace(*str)) |
| goto fail; |
| |
| /* count internal # of internal \0 */ |
| for (c = j = 0; j < size2 - 1; j++) { |
| if (!str[j]) { |
| pos = j; |
| c++; |
| } |
| } |
| if (*str == ':') { |
| /* first character after : must be valid */ |
| if (!str[1]) |
| goto fail; |
| /* beginning with : requires an embedded \0, |
| * verify that exactly 1 internal \0 exists |
| * trailing \0 already verified by aa_unpack_strdup |
| * |
| * convert \0 back to : for label_parse |
| */ |
| if (c == 1) |
| str[pos] = ':'; |
| else if (c > 1) |
| goto fail; |
| } else if (c) |
| /* fail - all other cases with embedded \0 */ |
| goto fail; |
| } |
| if (!aa_unpack_nameX(e, AA_ARRAYEND, NULL)) |
| goto fail; |
| if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) |
| goto fail; |
| |
| strs->table = table; |
| strs->size = size; |
| } |
| return true; |
| |
| fail: |
| kfree_sensitive(table); |
| e->pos = saved_pos; |
| return false; |
| } |
| |
| static bool unpack_xattrs(struct aa_ext *e, struct aa_profile *profile) |
| { |
| void *pos = e->pos; |
| |
| if (aa_unpack_nameX(e, AA_STRUCT, "xattrs")) { |
| u16 size; |
| int i; |
| |
| if (!aa_unpack_array(e, NULL, &size)) |
| goto fail; |
| profile->attach.xattr_count = size; |
| profile->attach.xattrs = kcalloc(size, sizeof(char *), GFP_KERNEL); |
| if (!profile->attach.xattrs) |
| goto fail; |
| for (i = 0; i < size; i++) { |
| if (!aa_unpack_strdup(e, &profile->attach.xattrs[i], NULL)) |
| goto fail; |
| } |
| if (!aa_unpack_nameX(e, AA_ARRAYEND, NULL)) |
| goto fail; |
| if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) |
| goto fail; |
| } |
| |
| return true; |
| |
| fail: |
| e->pos = pos; |
| return false; |
| } |
| |
| static bool unpack_secmark(struct aa_ext *e, struct aa_ruleset *rules) |
| { |
| void *pos = e->pos; |
| u16 size; |
| int i; |
| |
| if (aa_unpack_nameX(e, AA_STRUCT, "secmark")) { |
| if (!aa_unpack_array(e, NULL, &size)) |
| goto fail; |
| |
| rules->secmark = kcalloc(size, sizeof(struct aa_secmark), |
| GFP_KERNEL); |
| if (!rules->secmark) |
| goto fail; |
| |
| rules->secmark_count = size; |
| |
| for (i = 0; i < size; i++) { |
| if (!unpack_u8(e, &rules->secmark[i].audit, NULL)) |
| goto fail; |
| if (!unpack_u8(e, &rules->secmark[i].deny, NULL)) |
| goto fail; |
| if (!aa_unpack_strdup(e, &rules->secmark[i].label, NULL)) |
| goto fail; |
| } |
| if (!aa_unpack_nameX(e, AA_ARRAYEND, NULL)) |
| goto fail; |
| if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) |
| goto fail; |
| } |
| |
| return true; |
| |
| fail: |
| if (rules->secmark) { |
| for (i = 0; i < size; i++) |
| kfree(rules->secmark[i].label); |
| kfree(rules->secmark); |
| rules->secmark_count = 0; |
| rules->secmark = NULL; |
| } |
| |
| e->pos = pos; |
| return false; |
| } |
| |
| static bool unpack_rlimits(struct aa_ext *e, struct aa_ruleset *rules) |
| { |
| void *pos = e->pos; |
| |
| /* rlimits are optional */ |
| if (aa_unpack_nameX(e, AA_STRUCT, "rlimits")) { |
| u16 size; |
| int i; |
| u32 tmp = 0; |
| if (!aa_unpack_u32(e, &tmp, NULL)) |
| goto fail; |
| rules->rlimits.mask = tmp; |
| |
| if (!aa_unpack_array(e, NULL, &size) || |
| size > RLIM_NLIMITS) |
| goto fail; |
| for (i = 0; i < size; i++) { |
| u64 tmp2 = 0; |
| int a = aa_map_resource(i); |
| if (!aa_unpack_u64(e, &tmp2, NULL)) |
| goto fail; |
| rules->rlimits.limits[a].rlim_max = tmp2; |
| } |
| if (!aa_unpack_nameX(e, AA_ARRAYEND, NULL)) |
| goto fail; |
| if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) |
| goto fail; |
| } |
| return true; |
| |
| fail: |
| e->pos = pos; |
| return false; |
| } |
| |
| static bool unpack_perm(struct aa_ext *e, u32 version, struct aa_perms *perm) |
| { |
| if (version != 1) |
| return false; |
| |
| return aa_unpack_u32(e, &perm->allow, NULL) && |
| aa_unpack_u32(e, &perm->allow, NULL) && |
| aa_unpack_u32(e, &perm->deny, NULL) && |
| aa_unpack_u32(e, &perm->subtree, NULL) && |
| aa_unpack_u32(e, &perm->cond, NULL) && |
| aa_unpack_u32(e, &perm->kill, NULL) && |
| aa_unpack_u32(e, &perm->complain, NULL) && |
| aa_unpack_u32(e, &perm->prompt, NULL) && |
| aa_unpack_u32(e, &perm->audit, NULL) && |
| aa_unpack_u32(e, &perm->quiet, NULL) && |
| aa_unpack_u32(e, &perm->hide, NULL) && |
| aa_unpack_u32(e, &perm->xindex, NULL) && |
| aa_unpack_u32(e, &perm->tag, NULL) && |
| aa_unpack_u32(e, &perm->label, NULL); |
| } |
| |
| static ssize_t unpack_perms_table(struct aa_ext *e, struct aa_perms **perms) |
| { |
| void *pos = e->pos; |
| u16 size = 0; |
| |
| AA_BUG(!perms); |
| /* |
| * policy perms are optional, in which case perms are embedded |
| * in the dfa accept table |
| */ |
| if (aa_unpack_nameX(e, AA_STRUCT, "perms")) { |
| int i; |
| u32 version; |
| |
| if (!aa_unpack_u32(e, &version, "version")) |
| goto fail_reset; |
| if (!aa_unpack_array(e, NULL, &size)) |
| goto fail_reset; |
| *perms = kcalloc(size, sizeof(struct aa_perms), GFP_KERNEL); |
| if (!*perms) |
| goto fail_reset; |
| for (i = 0; i < size; i++) { |
| if (!unpack_perm(e, version, &(*perms)[i])) |
| goto fail; |
| } |
| if (!aa_unpack_nameX(e, AA_ARRAYEND, NULL)) |
| goto fail; |
| if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) |
| goto fail; |
| } else |
| *perms = NULL; |
| |
| return size; |
| |
| fail: |
| kfree(*perms); |
| fail_reset: |
| e->pos = pos; |
| return -EPROTO; |
| } |
| |
| static int unpack_pdb(struct aa_ext *e, struct aa_policydb *policy, |
| bool required_dfa, bool required_trans, |
| const char **info) |
| { |
| void *pos = e->pos; |
| int i, flags, error = -EPROTO; |
| ssize_t size; |
| |
| size = unpack_perms_table(e, &policy->perms); |
| if (size < 0) { |
| error = size; |
| policy->perms = NULL; |
| *info = "failed to unpack - perms"; |
| goto fail; |
| } |
| policy->size = size; |
| |
| if (policy->perms) { |
| /* perms table present accept is index */ |
| flags = TO_ACCEPT1_FLAG(YYTD_DATA32); |
| } else { |
| /* packed perms in accept1 and accept2 */ |
| flags = TO_ACCEPT1_FLAG(YYTD_DATA32) | |
| TO_ACCEPT2_FLAG(YYTD_DATA32); |
| } |
| |
| policy->dfa = unpack_dfa(e, flags); |
| if (IS_ERR(policy->dfa)) { |
| error = PTR_ERR(policy->dfa); |
| policy->dfa = NULL; |
| *info = "failed to unpack - dfa"; |
| goto fail; |
| } else if (!policy->dfa) { |
| if (required_dfa) { |
| *info = "missing required dfa"; |
| goto fail; |
| } |
| goto out; |
| } |
| |
| /* |
| * only unpack the following if a dfa is present |
| * |
| * sadly start was given different names for file and policydb |
| * but since it is optional we can try both |
| */ |
| if (!aa_unpack_u32(e, &policy->start[0], "start")) |
| /* default start state */ |
| policy->start[0] = DFA_START; |
| if (!aa_unpack_u32(e, &policy->start[AA_CLASS_FILE], "dfa_start")) { |
| /* default start state for xmatch and file dfa */ |
| policy->start[AA_CLASS_FILE] = DFA_START; |
| } /* setup class index */ |
| for (i = AA_CLASS_FILE + 1; i <= AA_CLASS_LAST; i++) { |
| policy->start[i] = aa_dfa_next(policy->dfa, policy->start[0], |
| i); |
| } |
| if (!unpack_trans_table(e, &policy->trans) && required_trans) { |
| *info = "failed to unpack profile transition table"; |
| goto fail; |
| } |
| |
| /* TODO: move compat mapping here, requires dfa merging first */ |
| /* TODO: move verify here, it has to be done after compat mappings */ |
| out: |
| return 0; |
| |
| fail: |
| e->pos = pos; |
| return error; |
| } |
| |
| static u32 strhash(const void *data, u32 len, u32 seed) |
| { |
| const char * const *key = data; |
| |
| return jhash(*key, strlen(*key), seed); |
| } |
| |
| static int datacmp(struct rhashtable_compare_arg *arg, const void *obj) |
| { |
| const struct aa_data *data = obj; |
| const char * const *key = arg->key; |
| |
| return strcmp(data->key, *key); |
| } |
| |
| /** |
| * unpack_profile - unpack a serialized profile |
| * @e: serialized data extent information (NOT NULL) |
| * @ns_name: pointer of newly allocated copy of %NULL in case of error |
| * |
| * NOTE: unpack profile sets audit struct if there is a failure |
| */ |
| static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name) |
| { |
| struct aa_ruleset *rules; |
| struct aa_profile *profile = NULL; |
| const char *tmpname, *tmpns = NULL, *name = NULL; |
| const char *info = "failed to unpack profile"; |
| size_t ns_len; |
| struct rhashtable_params params = { 0 }; |
| char *key = NULL; |
| struct aa_data *data; |
| int error = -EPROTO; |
| kernel_cap_t tmpcap; |
| u32 tmp; |
| |
| *ns_name = NULL; |
| |
| /* check that we have the right struct being passed */ |
| if (!aa_unpack_nameX(e, AA_STRUCT, "profile")) |
| goto fail; |
| if (!aa_unpack_str(e, &name, NULL)) |
| goto fail; |
| if (*name == '\0') |
| goto fail; |
| |
| tmpname = aa_splitn_fqname(name, strlen(name), &tmpns, &ns_len); |
| if (tmpns) { |
| *ns_name = kstrndup(tmpns, ns_len, GFP_KERNEL); |
| if (!*ns_name) { |
| info = "out of memory"; |
| error = -ENOMEM; |
| goto fail; |
| } |
| name = tmpname; |
| } |
| |
| profile = aa_alloc_profile(name, NULL, GFP_KERNEL); |
| if (!profile) { |
| info = "out of memory"; |
| error = -ENOMEM; |
| goto fail; |
| } |
| rules = list_first_entry(&profile->rules, typeof(*rules), list); |
| |
| /* profile renaming is optional */ |
| (void) aa_unpack_str(e, &profile->rename, "rename"); |
| |
| /* attachment string is optional */ |
| (void) aa_unpack_str(e, &profile->attach.xmatch_str, "attach"); |
| |
| /* xmatch is optional and may be NULL */ |
| error = unpack_pdb(e, &profile->attach.xmatch, false, false, &info); |
| if (error) { |
| info = "bad xmatch"; |
| goto fail; |
| } |
| |
| /* neither xmatch_len not xmatch_perms are optional if xmatch is set */ |
| if (profile->attach.xmatch.dfa) { |
| if (!aa_unpack_u32(e, &tmp, NULL)) { |
| info = "missing xmatch len"; |
| goto fail; |
| } |
| profile->attach.xmatch_len = tmp; |
| profile->attach.xmatch.start[AA_CLASS_XMATCH] = DFA_START; |
| error = aa_compat_map_xmatch(&profile->attach.xmatch); |
| if (error) { |
| info = "failed to convert xmatch permission table"; |
| goto fail; |
| } |
| } |
| |
| /* disconnected attachment string is optional */ |
| (void) aa_unpack_str(e, &profile->disconnected, "disconnected"); |
| |
| /* per profile debug flags (complain, audit) */ |
| if (!aa_unpack_nameX(e, AA_STRUCT, "flags")) { |
| info = "profile missing flags"; |
| goto fail; |
| } |
| info = "failed to unpack profile flags"; |
| if (!aa_unpack_u32(e, &tmp, NULL)) |
| goto fail; |
| if (tmp & PACKED_FLAG_HAT) |
| profile->label.flags |= FLAG_HAT; |
| if (tmp & PACKED_FLAG_DEBUG1) |
| profile->label.flags |= FLAG_DEBUG1; |
| if (tmp & PACKED_FLAG_DEBUG2) |
| profile->label.flags |= FLAG_DEBUG2; |
| if (!aa_unpack_u32(e, &tmp, NULL)) |
| goto fail; |
| if (tmp == PACKED_MODE_COMPLAIN || (e->version & FORCE_COMPLAIN_FLAG)) { |
| profile->mode = APPARMOR_COMPLAIN; |
| } else if (tmp == PACKED_MODE_ENFORCE) { |
| profile->mode = APPARMOR_ENFORCE; |
| } else if (tmp == PACKED_MODE_KILL) { |
| profile->mode = APPARMOR_KILL; |
| } else if (tmp == PACKED_MODE_UNCONFINED) { |
| profile->mode = APPARMOR_UNCONFINED; |
| profile->label.flags |= FLAG_UNCONFINED; |
| } else if (tmp == PACKED_MODE_USER) { |
| profile->mode = APPARMOR_USER; |
| } else { |
| goto fail; |
| } |
| if (!aa_unpack_u32(e, &tmp, NULL)) |
| goto fail; |
| if (tmp) |
| profile->audit = AUDIT_ALL; |
| |
| if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) |
| goto fail; |
| |
| /* path_flags is optional */ |
| if (aa_unpack_u32(e, &profile->path_flags, "path_flags")) |
| profile->path_flags |= profile->label.flags & |
| PATH_MEDIATE_DELETED; |
| else |
| /* set a default value if path_flags field is not present */ |
| profile->path_flags = PATH_MEDIATE_DELETED; |
| |
| info = "failed to unpack profile capabilities"; |
| if (!aa_unpack_u32(e, &(rules->caps.allow.cap[0]), NULL)) |
| goto fail; |
| if (!aa_unpack_u32(e, &(rules->caps.audit.cap[0]), NULL)) |
| goto fail; |
| if (!aa_unpack_u32(e, &(rules->caps.quiet.cap[0]), NULL)) |
| goto fail; |
| if (!aa_unpack_u32(e, &tmpcap.cap[0], NULL)) |
| goto fail; |
| |
| info = "failed to unpack upper profile capabilities"; |
| if (aa_unpack_nameX(e, AA_STRUCT, "caps64")) { |
| /* optional upper half of 64 bit caps */ |
| if (!aa_unpack_u32(e, &(rules->caps.allow.cap[1]), NULL)) |
| goto fail; |
| if (!aa_unpack_u32(e, &(rules->caps.audit.cap[1]), NULL)) |
| goto fail; |
| if (!aa_unpack_u32(e, &(rules->caps.quiet.cap[1]), NULL)) |
| goto fail; |
| if (!aa_unpack_u32(e, &(tmpcap.cap[1]), NULL)) |
| goto fail; |
| if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) |
| goto fail; |
| } |
| |
| info = "failed to unpack extended profile capabilities"; |
| if (aa_unpack_nameX(e, AA_STRUCT, "capsx")) { |
| /* optional extended caps mediation mask */ |
| if (!aa_unpack_u32(e, &(rules->caps.extended.cap[0]), NULL)) |
| goto fail; |
| if (!aa_unpack_u32(e, &(rules->caps.extended.cap[1]), NULL)) |
| goto fail; |
| if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) |
| goto fail; |
| } |
| |
| if (!unpack_xattrs(e, profile)) { |
| info = "failed to unpack profile xattrs"; |
| goto fail; |
| } |
| |
| if (!unpack_rlimits(e, rules)) { |
| info = "failed to unpack profile rlimits"; |
| goto fail; |
| } |
| |
| if (!unpack_secmark(e, rules)) { |
| info = "failed to unpack profile secmark rules"; |
| goto fail; |
| } |
| |
| if (aa_unpack_nameX(e, AA_STRUCT, "policydb")) { |
| /* generic policy dfa - optional and may be NULL */ |
| info = "failed to unpack policydb"; |
| error = unpack_pdb(e, &rules->policy, true, false, |
| &info); |
| if (error) |
| goto fail; |
| /* Fixup: drop when we get rid of start array */ |
| if (aa_dfa_next(rules->policy.dfa, rules->policy.start[0], |
| AA_CLASS_FILE)) |
| rules->policy.start[AA_CLASS_FILE] = |
| aa_dfa_next(rules->policy.dfa, |
| rules->policy.start[0], |
| AA_CLASS_FILE); |
| if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) |
| goto fail; |
| error = aa_compat_map_policy(&rules->policy, e->version); |
| if (error) { |
| info = "failed to remap policydb permission table"; |
| goto fail; |
| } |
| } else |
| rules->policy.dfa = aa_get_dfa(nulldfa); |
| |
| /* get file rules */ |
| error = unpack_pdb(e, &rules->file, false, true, &info); |
| if (error) { |
| goto fail; |
| } else if (rules->file.dfa) { |
| error = aa_compat_map_file(&rules->file); |
| if (error) { |
| info = "failed to remap file permission table"; |
| goto fail; |
| } |
| } else if (rules->policy.dfa && |
| rules->policy.start[AA_CLASS_FILE]) { |
| rules->file.dfa = aa_get_dfa(rules->policy.dfa); |
| rules->file.start[AA_CLASS_FILE] = rules->policy.start[AA_CLASS_FILE]; |
| } else |
| rules->file.dfa = aa_get_dfa(nulldfa); |
| |
| error = -EPROTO; |
| if (aa_unpack_nameX(e, AA_STRUCT, "data")) { |
| info = "out of memory"; |
| profile->data = kzalloc(sizeof(*profile->data), GFP_KERNEL); |
| if (!profile->data) { |
| error = -ENOMEM; |
| goto fail; |
| } |
| params.nelem_hint = 3; |
| params.key_len = sizeof(void *); |
| params.key_offset = offsetof(struct aa_data, key); |
| params.head_offset = offsetof(struct aa_data, head); |
| params.hashfn = strhash; |
| params.obj_cmpfn = datacmp; |
| |
| if (rhashtable_init(profile->data, ¶ms)) { |
| info = "failed to init key, value hash table"; |
| goto fail; |
| } |
| |
| while (aa_unpack_strdup(e, &key, NULL)) { |
| data = kzalloc(sizeof(*data), GFP_KERNEL); |
| if (!data) { |
| kfree_sensitive(key); |
| error = -ENOMEM; |
| goto fail; |
| } |
| |
| data->key = key; |
| data->size = aa_unpack_blob(e, &data->data, NULL); |
| data->data = kvmemdup(data->data, data->size); |
| if (data->size && !data->data) { |
| kfree_sensitive(data->key); |
| kfree_sensitive(data); |
| error = -ENOMEM; |
| goto fail; |
| } |
| |
| rhashtable_insert_fast(profile->data, &data->head, |
| profile->data->p); |
| } |
| |
| if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) { |
| info = "failed to unpack end of key, value data table"; |
| goto fail; |
| } |
| } |
| |
| if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) { |
| info = "failed to unpack end of profile"; |
| goto fail; |
| } |
| |
| return profile; |
| |
| fail: |
| if (error == 0) |
| /* default error covers most cases */ |
| error = -EPROTO; |
| if (*ns_name) { |
| kfree(*ns_name); |
| *ns_name = NULL; |
| } |
| if (profile) |
| name = NULL; |
| else if (!name) |
| name = "unknown"; |
| audit_iface(profile, NULL, name, info, e, error); |
| aa_free_profile(profile); |
| |
| return ERR_PTR(error); |
| } |
| |
| /** |
| * verify_header - unpack serialized stream header |
| * @e: serialized data read head (NOT NULL) |
| * @required: whether the header is required or optional |
| * @ns: Returns - namespace if one is specified else NULL (NOT NULL) |
| * |
| * Returns: error or 0 if header is good |
| */ |
| static int verify_header(struct aa_ext *e, int required, const char **ns) |
| { |
| int error = -EPROTONOSUPPORT; |
| const char *name = NULL; |
| *ns = NULL; |
| |
| /* get the interface version */ |
| if (!aa_unpack_u32(e, &e->version, "version")) { |
| if (required) { |
| audit_iface(NULL, NULL, NULL, "invalid profile format", |
| e, error); |
| return error; |
| } |
| } |
| |
| /* Check that the interface version is currently supported. |
| * if not specified use previous version |
| * Mask off everything that is not kernel abi version |
| */ |
| if (VERSION_LT(e->version, v5) || VERSION_GT(e->version, v9)) { |
| audit_iface(NULL, NULL, NULL, "unsupported interface version", |
| e, error); |
| return error; |
| } |
| |
| /* read the namespace if present */ |
| if (aa_unpack_str(e, &name, "namespace")) { |
| if (*name == '\0') { |
| audit_iface(NULL, NULL, NULL, "invalid namespace name", |
| e, error); |
| return error; |
| } |
| if (*ns && strcmp(*ns, name)) { |
| audit_iface(NULL, NULL, NULL, "invalid ns change", e, |
| error); |
| } else if (!*ns) { |
| *ns = kstrdup(name, GFP_KERNEL); |
| if (!*ns) |
| return -ENOMEM; |
| } |
| } |
| |
| return 0; |
| } |
| |
| static bool verify_xindex(int xindex, int table_size) |
| { |
| int index, xtype; |
| xtype = xindex & AA_X_TYPE_MASK; |
| index = xindex & AA_X_INDEX_MASK; |
| if (xtype == AA_X_TABLE && index >= table_size) |
| return false; |
| return true; |
| } |
| |
| /* verify dfa xindexes are in range of transition tables */ |
| static bool verify_dfa_xindex(struct aa_dfa *dfa, int table_size) |
| { |
| int i; |
| for (i = 0; i < dfa->tables[YYTD_ID_ACCEPT]->td_lolen; i++) { |
| if (!verify_xindex(ACCEPT_TABLE(dfa)[i], table_size)) |
| return false; |
| } |
| return true; |
| } |
| |
| static bool verify_perm(struct aa_perms *perm) |
| { |
| /* TODO: allow option to just force the perms into a valid state */ |
| if (perm->allow & perm->deny) |
| return false; |
| if (perm->subtree & ~perm->allow) |
| return false; |
| if (perm->cond & (perm->allow | perm->deny)) |
| return false; |
| if (perm->kill & perm->allow) |
| return false; |
| if (perm->complain & (perm->allow | perm->deny)) |
| return false; |
| if (perm->prompt & (perm->allow | perm->deny)) |
| return false; |
| if (perm->complain & perm->prompt) |
| return false; |
| if (perm->hide & perm->allow) |
| return false; |
| |
| return true; |
| } |
| |
| static bool verify_perms(struct aa_policydb *pdb) |
| { |
| int i; |
| |
| for (i = 0; i < pdb->size; i++) { |
| if (!verify_perm(&pdb->perms[i])) |
| return false; |
| /* verify indexes into str table */ |
| if (pdb->perms[i].xindex >= pdb->trans.size) |
| return false; |
| if (pdb->perms[i].tag >= pdb->trans.size) |
| return false; |
| if (pdb->perms[i].label >= pdb->trans.size) |
| return false; |
| } |
| |
| return true; |
| } |
| |
| /** |
| * verify_profile - Do post unpack analysis to verify profile consistency |
| * @profile: profile to verify (NOT NULL) |
| * |
| * Returns: 0 if passes verification else error |
| * |
| * This verification is post any unpack mapping or changes |
| */ |
| static int verify_profile(struct aa_profile *profile) |
| { |
| struct aa_ruleset *rules = list_first_entry(&profile->rules, |
| typeof(*rules), list); |
| if (!rules) |
| return 0; |
| |
| if ((rules->file.dfa && !verify_dfa_xindex(rules->file.dfa, |
| rules->file.trans.size)) || |
| (rules->policy.dfa && |
| !verify_dfa_xindex(rules->policy.dfa, rules->policy.trans.size))) { |
| audit_iface(profile, NULL, NULL, |
| "Unpack: Invalid named transition", NULL, -EPROTO); |
| return -EPROTO; |
| } |
| |
| if (!verify_perms(&rules->file)) { |
| audit_iface(profile, NULL, NULL, |
| "Unpack: Invalid perm index", NULL, -EPROTO); |
| return -EPROTO; |
| } |
| if (!verify_perms(&rules->policy)) { |
| audit_iface(profile, NULL, NULL, |
| "Unpack: Invalid perm index", NULL, -EPROTO); |
| return -EPROTO; |
| } |
| if (!verify_perms(&profile->attach.xmatch)) { |
| audit_iface(profile, NULL, NULL, |
| "Unpack: Invalid perm index", NULL, -EPROTO); |
| return -EPROTO; |
| } |
| |
| return 0; |
| } |
| |
| void aa_load_ent_free(struct aa_load_ent *ent) |
| { |
| if (ent) { |
| aa_put_profile(ent->rename); |
| aa_put_profile(ent->old); |
| aa_put_profile(ent->new); |
| kfree(ent->ns_name); |
| kfree_sensitive(ent); |
| } |
| } |
| |
| struct aa_load_ent *aa_load_ent_alloc(void) |
| { |
| struct aa_load_ent *ent = kzalloc(sizeof(*ent), GFP_KERNEL); |
| if (ent) |
| INIT_LIST_HEAD(&ent->list); |
| return ent; |
| } |
| |
| static int compress_zstd(const char *src, size_t slen, char **dst, size_t *dlen) |
| { |
| #ifdef CONFIG_SECURITY_APPARMOR_EXPORT_BINARY |
| const zstd_parameters params = |
| zstd_get_params(aa_g_rawdata_compression_level, slen); |
| const size_t wksp_len = zstd_cctx_workspace_bound(¶ms.cParams); |
| void *wksp = NULL; |
| zstd_cctx *ctx = NULL; |
| size_t out_len = zstd_compress_bound(slen); |
| void *out = NULL; |
| int ret = 0; |
| |
| out = kvzalloc(out_len, GFP_KERNEL); |
| if (!out) { |
| ret = -ENOMEM; |
| goto cleanup; |
| } |
| |
| wksp = kvzalloc(wksp_len, GFP_KERNEL); |
| if (!wksp) { |
| ret = -ENOMEM; |
| goto cleanup; |
| } |
| |
| ctx = zstd_init_cctx(wksp, wksp_len); |
| if (!ctx) { |
| ret = -EINVAL; |
| goto cleanup; |
| } |
| |
| out_len = zstd_compress_cctx(ctx, out, out_len, src, slen, ¶ms); |
| if (zstd_is_error(out_len) || out_len >= slen) { |
| ret = -EINVAL; |
| goto cleanup; |
| } |
| |
| if (is_vmalloc_addr(out)) { |
| *dst = kvzalloc(out_len, GFP_KERNEL); |
| if (*dst) { |
| memcpy(*dst, out, out_len); |
| kvfree(out); |
| out = NULL; |
| } |
| } else { |
| /* |
| * If the staging buffer was kmalloc'd, then using krealloc is |
| * probably going to be faster. The destination buffer will |
| * always be smaller, so it's just shrunk, avoiding a memcpy |
| */ |
| *dst = krealloc(out, out_len, GFP_KERNEL); |
| } |
| |
| if (!*dst) { |
| ret = -ENOMEM; |
| goto cleanup; |
| } |
| |
| *dlen = out_len; |
| |
| cleanup: |
| if (ret) { |
| kvfree(out); |
| *dst = NULL; |
| } |
| |
| kvfree(wksp); |
| return ret; |
| #else |
| *dlen = slen; |
| return 0; |
| #endif |
| } |
| |
| static int compress_loaddata(struct aa_loaddata *data) |
| { |
| AA_BUG(data->compressed_size > 0); |
| |
| /* |
| * Shortcut the no compression case, else we increase the amount of |
| * storage required by a small amount |
| */ |
| if (aa_g_rawdata_compression_level != 0) { |
| void *udata = data->data; |
| int error = compress_zstd(udata, data->size, &data->data, |
| &data->compressed_size); |
| if (error) { |
| data->compressed_size = data->size; |
| return error; |
| } |
| if (udata != data->data) |
| kvfree(udata); |
| } else |
| data->compressed_size = data->size; |
| |
| return 0; |
| } |
| |
| /** |
| * aa_unpack - unpack packed binary profile(s) data loaded from user space |
| * @udata: user data copied to kmem (NOT NULL) |
| * @lh: list to place unpacked profiles in a aa_repl_ws |
| * @ns: Returns namespace profile is in if specified else NULL (NOT NULL) |
| * |
| * Unpack user data and return refcounted allocated profile(s) stored in |
| * @lh in order of discovery, with the list chain stored in base.list |
| * or error |
| * |
| * Returns: profile(s) on @lh else error pointer if fails to unpack |
| */ |
| int aa_unpack(struct aa_loaddata *udata, struct list_head *lh, |
| const char **ns) |
| { |
| struct aa_load_ent *tmp, *ent; |
| struct aa_profile *profile = NULL; |
| char *ns_name = NULL; |
| int error; |
| struct aa_ext e = { |
| .start = udata->data, |
| .end = udata->data + udata->size, |
| .pos = udata->data, |
| }; |
| |
| *ns = NULL; |
| while (e.pos < e.end) { |
| void *start; |
| error = verify_header(&e, e.pos == e.start, ns); |
| if (error) |
| goto fail; |
| |
| start = e.pos; |
| profile = unpack_profile(&e, &ns_name); |
| if (IS_ERR(profile)) { |
| error = PTR_ERR(profile); |
| goto fail; |
| } |
| |
| error = verify_profile(profile); |
| if (error) |
| goto fail_profile; |
| |
| if (aa_g_hash_policy) |
| error = aa_calc_profile_hash(profile, e.version, start, |
| e.pos - start); |
| if (error) |
| goto fail_profile; |
| |
| ent = aa_load_ent_alloc(); |
| if (!ent) { |
| error = -ENOMEM; |
| goto fail_profile; |
| } |
| |
| ent->new = profile; |
| ent->ns_name = ns_name; |
| ns_name = NULL; |
| list_add_tail(&ent->list, lh); |
| } |
| udata->abi = e.version & K_ABI_MASK; |
| if (aa_g_hash_policy) { |
| udata->hash = aa_calc_hash(udata->data, udata->size); |
| if (IS_ERR(udata->hash)) { |
| error = PTR_ERR(udata->hash); |
| udata->hash = NULL; |
| goto fail; |
| } |
| } |
| |
| if (aa_g_export_binary) { |
| error = compress_loaddata(udata); |
| if (error) |
| goto fail; |
| } |
| return 0; |
| |
| fail_profile: |
| kfree(ns_name); |
| aa_put_profile(profile); |
| |
| fail: |
| list_for_each_entry_safe(ent, tmp, lh, list) { |
| list_del_init(&ent->list); |
| aa_load_ent_free(ent); |
| } |
| |
| return error; |
| } |