| /* |
| * 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. |
| * |
| * 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 of the |
| * License. |
| * |
| * 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 <linux/ctype.h> |
| #include <linux/errno.h> |
| |
| #include "include/apparmor.h" |
| #include "include/audit.h" |
| #include "include/context.h" |
| #include "include/crypto.h" |
| #include "include/match.h" |
| #include "include/path.h" |
| #include "include/policy.h" |
| #include "include/policy_unpack.h" |
| |
| #define K_ABI_MASK 0x3ff |
| #define FORCE_COMPLAIN_FLAG 0x800 |
| #define VERSION_LT(X, Y) (((X) & K_ABI_MASK) < ((Y) & K_ABI_MASK)) |
| #define VERSION_GT(X, Y) (((X) & K_ABI_MASK) > ((Y) & K_ABI_MASK)) |
| |
| #define v5 5 /* base version */ |
| #define v6 6 /* per entry policydb mediation check */ |
| #define v7 7 /* full network masking */ |
| |
| /* |
| * The AppArmor interface treats data as a type byte followed by the |
| * actual data. The interface has the notion of a a named entry |
| * which has a name (AA_NAME typecode followed by name string) followed by |
| * the entries typecode and data. Named types allow for optional |
| * elements and extensions to be added and tested for without breaking |
| * backwards compatibility. |
| */ |
| |
| enum aa_code { |
| AA_U8, |
| AA_U16, |
| AA_U32, |
| AA_U64, |
| AA_NAME, /* same as string except it is items name */ |
| AA_STRING, |
| AA_BLOB, |
| AA_STRUCT, |
| AA_STRUCTEND, |
| AA_LIST, |
| AA_LISTEND, |
| AA_ARRAY, |
| AA_ARRAYEND, |
| }; |
| |
| /* |
| * aa_ext is the read of the buffer containing the serialized profile. The |
| * data is copied into a kernel buffer in apparmorfs and then handed off to |
| * the unpack routines. |
| */ |
| struct aa_ext { |
| void *start; |
| void *end; |
| void *pos; /* pointer to current position in the buffer */ |
| u32 version; |
| }; |
| |
| /* 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, 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(!data->dents[AAFS_LOADDATA_REVISION]); |
| AA_BUG(!mutex_is_locked(&data->ns->lock)); |
| AA_BUG(data->revision > revision); |
| |
| data->revision = 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 (aa_g_hash_policy && memcmp(l->hash, r->hash, aa_hash_size()) != 0) |
| return false; |
| return memcmp(l->data, r->data, 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); |
| } |
| |
| kzfree(d->hash); |
| kfree(d->name); |
| kvfree(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 = kvzalloc(sizeof(*d) + size, GFP_KERNEL); |
| |
| if (d == NULL) |
| return ERR_PTR(-ENOMEM); |
| kref_init(&d->count); |
| INIT_LIST_HEAD(&d->list); |
| |
| return d; |
| } |
| |
| /* test if read will be in packed data bounds */ |
| static bool inbounds(struct aa_ext *e, size_t size) |
| { |
| return (size <= e->end - e->pos); |
| } |
| |
| /** |
| * aa_u16_chunck - 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. |
| */ |
| static size_t unpack_u16_chunk(struct aa_ext *e, char **chunk) |
| { |
| size_t size = 0; |
| |
| if (!inbounds(e, sizeof(u16))) |
| return 0; |
| size = le16_to_cpu(get_unaligned((__le16 *) e->pos)); |
| e->pos += sizeof(__le16); |
| if (!inbounds(e, size)) |
| return 0; |
| *chunk = e->pos; |
| e->pos += size; |
| return size; |
| } |
| |
| /* unpack control byte */ |
| static bool unpack_X(struct aa_ext *e, enum aa_code code) |
| { |
| if (!inbounds(e, 1)) |
| return 0; |
| if (*(u8 *) e->pos != code) |
| return 0; |
| e->pos++; |
| return 1; |
| } |
| |
| /** |
| * 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 1 on success (both type code and name tests match) and the read |
| * head is advanced past the headers |
| * |
| * Returns: 0 if either match fails, the read head does not move |
| */ |
| static bool 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 (unpack_X(e, AA_NAME)) { |
| char *tag = NULL; |
| size_t size = unpack_u16_chunk(e, &tag); |
| /* if a name is specified it must match. otherwise skip tag */ |
| if (name && (!size || 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 (unpack_X(e, code)) |
| return 1; |
| |
| fail: |
| e->pos = pos; |
| return 0; |
| } |
| |
| static bool unpack_u32(struct aa_ext *e, u32 *data, const char *name) |
| { |
| if (unpack_nameX(e, AA_U32, name)) { |
| if (!inbounds(e, sizeof(u32))) |
| return 0; |
| if (data) |
| *data = le32_to_cpu(get_unaligned((__le32 *) e->pos)); |
| e->pos += sizeof(u32); |
| return 1; |
| } |
| return 0; |
| } |
| |
| static bool unpack_u64(struct aa_ext *e, u64 *data, const char *name) |
| { |
| if (unpack_nameX(e, AA_U64, name)) { |
| if (!inbounds(e, sizeof(u64))) |
| return 0; |
| if (data) |
| *data = le64_to_cpu(get_unaligned((__le64 *) e->pos)); |
| e->pos += sizeof(u64); |
| return 1; |
| } |
| return 0; |
| } |
| |
| static size_t unpack_array(struct aa_ext *e, const char *name) |
| { |
| if (unpack_nameX(e, AA_ARRAY, name)) { |
| int size; |
| if (!inbounds(e, sizeof(u16))) |
| return 0; |
| size = (int)le16_to_cpu(get_unaligned((__le16 *) e->pos)); |
| e->pos += sizeof(u16); |
| return size; |
| } |
| return 0; |
| } |
| |
| static size_t unpack_blob(struct aa_ext *e, char **blob, const char *name) |
| { |
| if (unpack_nameX(e, AA_BLOB, name)) { |
| u32 size; |
| if (!inbounds(e, sizeof(u32))) |
| return 0; |
| size = le32_to_cpu(get_unaligned((__le32 *) e->pos)); |
| e->pos += sizeof(u32); |
| if (inbounds(e, (size_t) size)) { |
| *blob = e->pos; |
| e->pos += size; |
| return size; |
| } |
| } |
| return 0; |
| } |
| |
| static int 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 (unpack_nameX(e, AA_STRING, name)) { |
| size = 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; |
| } |
| |
| static int unpack_strdup(struct aa_ext *e, char **string, const char *name) |
| { |
| const char *tmp; |
| void *pos = e->pos; |
| int res = 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; |
| } |
| |
| #define DFA_VALID_PERM_MASK 0xffffffff |
| #define DFA_VALID_PERM2_MASK 0xffffffff |
| |
| /** |
| * verify_accept - verify the accept tables of a dfa |
| * @dfa: dfa to verify accept tables of (NOT NULL) |
| * @flags: flags governing dfa |
| * |
| * Returns: 1 if valid accept tables else 0 if error |
| */ |
| static bool verify_accept(struct aa_dfa *dfa, int flags) |
| { |
| int i; |
| |
| /* verify accept permissions */ |
| for (i = 0; i < dfa->tables[YYTD_ID_ACCEPT]->td_lolen; i++) { |
| int mode = ACCEPT_TABLE(dfa)[i]; |
| |
| if (mode & ~DFA_VALID_PERM_MASK) |
| return 0; |
| |
| if (ACCEPT_TABLE2(dfa)[i] & ~DFA_VALID_PERM2_MASK) |
| return 0; |
| } |
| return 1; |
| } |
| |
| /** |
| * unpack_dfa - unpack a file rule dfa |
| * @e: serialized data extent information (NOT NULL) |
| * |
| * returns dfa or ERR_PTR or NULL if no dfa |
| */ |
| static struct aa_dfa *unpack_dfa(struct aa_ext *e) |
| { |
| char *blob = NULL; |
| size_t size; |
| struct aa_dfa *dfa = NULL; |
| |
| size = 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; |
| int flags = TO_ACCEPT1_FLAG(YYTD_DATA32) | |
| TO_ACCEPT2_FLAG(YYTD_DATA32) | DFA_FLAG_VERIFY_STATES; |
| dfa = aa_dfa_unpack(blob + pad, size - pad, flags); |
| |
| if (IS_ERR(dfa)) |
| return dfa; |
| |
| if (!verify_accept(dfa, flags)) |
| goto fail; |
| } |
| |
| return dfa; |
| |
| fail: |
| aa_put_dfa(dfa); |
| return ERR_PTR(-EPROTO); |
| } |
| |
| /** |
| * unpack_trans_table - unpack a profile transition table |
| * @e: serialized data extent information (NOT NULL) |
| * @profile: profile to add the accept table to (NOT NULL) |
| * |
| * Returns: 1 if table successfully unpacked |
| */ |
| static bool unpack_trans_table(struct aa_ext *e, struct aa_profile *profile) |
| { |
| void *saved_pos = e->pos; |
| |
| /* exec table is optional */ |
| if (unpack_nameX(e, AA_STRUCT, "xtable")) { |
| int i, size; |
| |
| size = unpack_array(e, NULL); |
| /* currently 4 exec bits and entries 0-3 are reserved iupcx */ |
| if (size > 16 - 4) |
| goto fail; |
| profile->file.trans.table = kzalloc(sizeof(char *) * size, |
| GFP_KERNEL); |
| if (!profile->file.trans.table) |
| goto fail; |
| |
| profile->file.trans.size = size; |
| for (i = 0; i < size; i++) { |
| char *str; |
| int c, j, pos, size2 = unpack_strdup(e, &str, NULL); |
| /* unpack_strdup verifies that the last character is |
| * null termination byte. |
| */ |
| if (!size2) |
| goto fail; |
| profile->file.trans.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 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 (!unpack_nameX(e, AA_ARRAYEND, NULL)) |
| goto fail; |
| if (!unpack_nameX(e, AA_STRUCTEND, NULL)) |
| goto fail; |
| } |
| return 1; |
| |
| fail: |
| aa_free_domain_entries(&profile->file.trans); |
| e->pos = saved_pos; |
| return 0; |
| } |
| |
| static bool unpack_rlimits(struct aa_ext *e, struct aa_profile *profile) |
| { |
| void *pos = e->pos; |
| |
| /* rlimits are optional */ |
| if (unpack_nameX(e, AA_STRUCT, "rlimits")) { |
| int i, size; |
| u32 tmp = 0; |
| if (!unpack_u32(e, &tmp, NULL)) |
| goto fail; |
| profile->rlimits.mask = tmp; |
| |
| size = unpack_array(e, NULL); |
| if (size > RLIM_NLIMITS) |
| goto fail; |
| for (i = 0; i < size; i++) { |
| u64 tmp2 = 0; |
| int a = aa_map_resource(i); |
| if (!unpack_u64(e, &tmp2, NULL)) |
| goto fail; |
| profile->rlimits.limits[a].rlim_max = tmp2; |
| } |
| if (!unpack_nameX(e, AA_ARRAYEND, NULL)) |
| goto fail; |
| if (!unpack_nameX(e, AA_STRUCTEND, NULL)) |
| goto fail; |
| } |
| return 1; |
| |
| fail: |
| e->pos = pos; |
| return 0; |
| } |
| |
| static void *kvmemdup(const void *src, size_t len) |
| { |
| void *p = kvmalloc(len, GFP_KERNEL); |
| |
| if (p) |
| memcpy(p, src, len); |
| return p; |
| } |
| |
| 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) |
| * |
| * 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_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 i, error = -EPROTO; |
| kernel_cap_t tmpcap; |
| u32 tmp; |
| |
| *ns_name = NULL; |
| |
| /* check that we have the right struct being passed */ |
| if (!unpack_nameX(e, AA_STRUCT, "profile")) |
| goto fail; |
| if (!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"; |
| goto fail; |
| } |
| name = tmpname; |
| } |
| |
| profile = aa_alloc_profile(name, NULL, GFP_KERNEL); |
| if (!profile) |
| return ERR_PTR(-ENOMEM); |
| |
| /* profile renaming is optional */ |
| (void) unpack_str(e, &profile->rename, "rename"); |
| |
| /* attachment string is optional */ |
| (void) unpack_str(e, &profile->attach, "attach"); |
| |
| /* xmatch is optional and may be NULL */ |
| profile->xmatch = unpack_dfa(e); |
| if (IS_ERR(profile->xmatch)) { |
| error = PTR_ERR(profile->xmatch); |
| profile->xmatch = NULL; |
| info = "bad xmatch"; |
| goto fail; |
| } |
| /* xmatch_len is not optional if xmatch is set */ |
| if (profile->xmatch) { |
| if (!unpack_u32(e, &tmp, NULL)) { |
| info = "missing xmatch len"; |
| goto fail; |
| } |
| profile->xmatch_len = tmp; |
| } |
| |
| /* disconnected attachment string is optional */ |
| (void) unpack_str(e, &profile->disconnected, "disconnected"); |
| |
| /* per profile debug flags (complain, audit) */ |
| if (!unpack_nameX(e, AA_STRUCT, "flags")) { |
| info = "profile missing flags"; |
| goto fail; |
| } |
| info = "failed to unpack profile flags"; |
| if (!unpack_u32(e, &tmp, NULL)) |
| goto fail; |
| if (tmp & PACKED_FLAG_HAT) |
| profile->label.flags |= FLAG_HAT; |
| if (!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_KILL) |
| profile->mode = APPARMOR_KILL; |
| else if (tmp == PACKED_MODE_UNCONFINED) |
| profile->mode = APPARMOR_UNCONFINED; |
| if (!unpack_u32(e, &tmp, NULL)) |
| goto fail; |
| if (tmp) |
| profile->audit = AUDIT_ALL; |
| |
| if (!unpack_nameX(e, AA_STRUCTEND, NULL)) |
| goto fail; |
| |
| /* path_flags is optional */ |
| if (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 (!unpack_u32(e, &(profile->caps.allow.cap[0]), NULL)) |
| goto fail; |
| if (!unpack_u32(e, &(profile->caps.audit.cap[0]), NULL)) |
| goto fail; |
| if (!unpack_u32(e, &(profile->caps.quiet.cap[0]), NULL)) |
| goto fail; |
| if (!unpack_u32(e, &tmpcap.cap[0], NULL)) |
| goto fail; |
| |
| info = "failed to unpack upper profile capabilities"; |
| if (unpack_nameX(e, AA_STRUCT, "caps64")) { |
| /* optional upper half of 64 bit caps */ |
| if (!unpack_u32(e, &(profile->caps.allow.cap[1]), NULL)) |
| goto fail; |
| if (!unpack_u32(e, &(profile->caps.audit.cap[1]), NULL)) |
| goto fail; |
| if (!unpack_u32(e, &(profile->caps.quiet.cap[1]), NULL)) |
| goto fail; |
| if (!unpack_u32(e, &(tmpcap.cap[1]), NULL)) |
| goto fail; |
| if (!unpack_nameX(e, AA_STRUCTEND, NULL)) |
| goto fail; |
| } |
| |
| info = "failed to unpack extended profile capabilities"; |
| if (unpack_nameX(e, AA_STRUCT, "capsx")) { |
| /* optional extended caps mediation mask */ |
| if (!unpack_u32(e, &(profile->caps.extended.cap[0]), NULL)) |
| goto fail; |
| if (!unpack_u32(e, &(profile->caps.extended.cap[1]), NULL)) |
| goto fail; |
| if (!unpack_nameX(e, AA_STRUCTEND, NULL)) |
| goto fail; |
| } |
| |
| if (!unpack_rlimits(e, profile)) { |
| info = "failed to unpack profile rlimits"; |
| goto fail; |
| } |
| |
| if (unpack_nameX(e, AA_STRUCT, "policydb")) { |
| /* generic policy dfa - optional and may be NULL */ |
| info = "failed to unpack policydb"; |
| profile->policy.dfa = unpack_dfa(e); |
| if (IS_ERR(profile->policy.dfa)) { |
| error = PTR_ERR(profile->policy.dfa); |
| profile->policy.dfa = NULL; |
| goto fail; |
| } else if (!profile->policy.dfa) { |
| error = -EPROTO; |
| goto fail; |
| } |
| if (!unpack_u32(e, &profile->policy.start[0], "start")) |
| /* default start state */ |
| profile->policy.start[0] = DFA_START; |
| /* setup class index */ |
| for (i = AA_CLASS_FILE; i <= AA_CLASS_LAST; i++) { |
| profile->policy.start[i] = |
| aa_dfa_next(profile->policy.dfa, |
| profile->policy.start[0], |
| i); |
| } |
| if (!unpack_nameX(e, AA_STRUCTEND, NULL)) |
| goto fail; |
| } else |
| profile->policy.dfa = aa_get_dfa(nulldfa); |
| |
| /* get file rules */ |
| profile->file.dfa = unpack_dfa(e); |
| if (IS_ERR(profile->file.dfa)) { |
| error = PTR_ERR(profile->file.dfa); |
| profile->file.dfa = NULL; |
| info = "failed to unpack profile file rules"; |
| goto fail; |
| } else if (profile->file.dfa) { |
| if (!unpack_u32(e, &profile->file.start, "dfa_start")) |
| /* default start state */ |
| profile->file.start = DFA_START; |
| } else if (profile->policy.dfa && |
| profile->policy.start[AA_CLASS_FILE]) { |
| profile->file.dfa = aa_get_dfa(profile->policy.dfa); |
| profile->file.start = profile->policy.start[AA_CLASS_FILE]; |
| } else |
| profile->file.dfa = aa_get_dfa(nulldfa); |
| |
| if (!unpack_trans_table(e, profile)) { |
| info = "failed to unpack profile transition table"; |
| goto fail; |
| } |
| |
| if (unpack_nameX(e, AA_STRUCT, "data")) { |
| info = "out of memory"; |
| profile->data = kzalloc(sizeof(*profile->data), GFP_KERNEL); |
| if (!profile->data) |
| 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 (unpack_strdup(e, &key, NULL)) { |
| data = kzalloc(sizeof(*data), GFP_KERNEL); |
| if (!data) { |
| kzfree(key); |
| goto fail; |
| } |
| |
| data->key = key; |
| data->size = unpack_blob(e, &data->data, NULL); |
| data->data = kvmemdup(data->data, data->size); |
| if (data->size && !data->data) { |
| kzfree(data->key); |
| kzfree(data); |
| goto fail; |
| } |
| |
| rhashtable_insert_fast(profile->data, &data->head, |
| profile->data->p); |
| } |
| |
| if (!unpack_nameX(e, AA_STRUCTEND, NULL)) { |
| info = "failed to unpack end of key, value data table"; |
| goto fail; |
| } |
| } |
| |
| if (!unpack_nameX(e, AA_STRUCTEND, NULL)) { |
| info = "failed to unpack end of profile"; |
| goto fail; |
| } |
| |
| return profile; |
| |
| fail: |
| 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_head - 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 (!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, v7)) { |
| audit_iface(NULL, NULL, NULL, "unsupported interface version", |
| e, error); |
| return error; |
| } |
| |
| /* read the namespace if present */ |
| if (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 = name; |
| } |
| |
| 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 0; |
| return 1; |
| } |
| |
| /* 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(dfa_user_xindex(dfa, i), table_size)) |
| return 0; |
| if (!verify_xindex(dfa_other_xindex(dfa, i), table_size)) |
| return 0; |
| } |
| return 1; |
| } |
| |
| /** |
| * verify_profile - Do post unpack analysis to verify profile consistency |
| * @profile: profile to verify (NOT NULL) |
| * |
| * Returns: 0 if passes verification else error |
| */ |
| static int verify_profile(struct aa_profile *profile) |
| { |
| if (profile->file.dfa && |
| !verify_dfa_xindex(profile->file.dfa, |
| profile->file.trans.size)) { |
| audit_iface(profile, NULL, NULL, "Invalid named transition", |
| 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); |
| kzfree(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; |
| } |
| |
| /** |
| * 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; |
| int error; |
| struct aa_ext e = { |
| .start = udata->data, |
| .end = udata->data + udata->size, |
| .pos = udata->data, |
| }; |
| |
| *ns = NULL; |
| while (e.pos < e.end) { |
| char *ns_name = NULL; |
| 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; |
| 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; |
| } |
| } |
| return 0; |
| |
| fail_profile: |
| 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; |
| } |