// SPDX-License-Identifier: GPL-2.0-only/* * AppArmor security module * * This file contains basic common functions used in AppArmor * * Copyright (C) 1998-2008 Novell/SUSE * Copyright 2009-2010 Canonical Ltd. */ #include <linux/ctype.h>#include <linux/mm.h>#include <linux/slab.h>#include <linux/string.h>#include <linux/vmalloc.h> #include "include/audit.h"#include "include/apparmor.h"#include "include/lib.h"#include "include/perms.h"#include "include/policy.h" struct aa_perms nullperms;struct aa_perms allperms = { .allow = ALL_PERMS_MASK, .quiet = ALL_PERMS_MASK, .hide = ALL_PERMS_MASK }; struct val_table_ent { const char *str; int value;}; static struct val_table_ent debug_values_table[] = { { "N", DEBUG_NONE }, { "none", DEBUG_NONE }, { "n", DEBUG_NONE }, { "0", DEBUG_NONE }, { "all", DEBUG_ALL }, { "Y", DEBUG_ALL }, { "y", DEBUG_ALL }, { "1", DEBUG_ALL }, { "abs_root", DEBUG_LABEL_ABS_ROOT }, { "label", DEBUG_LABEL }, { "domain", DEBUG_DOMAIN }, { "policy", DEBUG_POLICY }, { "interface", DEBUG_INTERFACE }, { "unpack", DEBUG_UNPACK }, { "tags", DEBUG_TAGS }, { NULL, 0 }}; static struct val_table_ent *val_table_find_ent(struct val_table_ent *table, const char *name, size_t len){ struct val_table_ent *entry; for (entry = table; entry->str != NULL; entry++) { if (strncmp(entry->str, name, len) == 0 && strlen(entry->str) == len) return entry; } return NULL;} int aa_parse_debug_params(const char *str){ struct val_table_ent *ent; const char *next; int val = 0; do { size_t n = strcspn(str, "\r\n,"); next = str + n; ent = val_table_find_ent(debug_values_table, str, next - str); if (ent) val |= ent->value; else AA_DEBUG(DEBUG_INTERFACE, "unknown debug type '%.*s'", (int)(next - str), str); str = next + 1; } while (*next != 0); return val;} /** * val_mask_to_str - convert a perm mask to its short string * @str: character buffer to store string in (at least 10 characters) * @size: size of the @str buffer * @table: NUL-terminated character buffer of permission characters (NOT NULL) * @mask: permission mask to convert */static int val_mask_to_str(char *str, size_t size, const struct val_table_ent *table, u32 mask){ const struct val_table_ent *ent; int total = 0; for (ent = table; ent->str; ent++) { if (ent->value && (ent->value & mask) == ent->value) { int len = scnprintf(str, size, "%s%s", total ? "," : "", ent->str); size -= len; str += len; total += len; mask &= ~ent->value; } } return total;} int aa_print_debug_params(char *buffer){ if (!aa_g_debug) return sprintf(buffer, "N"); return val_mask_to_str(buffer, PAGE_SIZE, debug_values_table, aa_g_debug);} bool aa_resize_str_table(struct aa_str_table *t, int newsize, gfp_t gfp){ struct aa_str_table_ent *n; int i; if (t->size == newsize) return true; n = kzalloc_objs(*n, newsize, gfp); if (!n) return false; for (i = 0; i < min(t->size, newsize); i++) n[i] = t->table[i]; for (; i < t->size; i++) kfree_sensitive(t->table[i].strs); if (newsize > t->size) memset(&n[t->size], 0, (newsize-t->size)*sizeof(*n)); kfree_sensitive(t->table); t->table = n; t->size = newsize; return true;} /** * aa_destroy_str_table - free entries str table * @t: the string table to free (MAYBE NULL) */void aa_destroy_str_table(struct aa_str_table *t){ int i; if (t) { if (!t->table) return; for (i = 0; i < t->size; i++) kfree_sensitive(t->table[i].strs); kfree_sensitive(t->table); t->table = NULL; t->size = 0; }} /** * skipn_spaces - Removes leading whitespace from @str. * @str: The string to be stripped. * @n: length of str to parse, will stop at \0 if encountered before n * * Returns a pointer to the first non-whitespace character in @str. * if all whitespace will return NULL */ const char *skipn_spaces(const char *str, size_t n){ for (; n && isspace(*str); --n) ++str; if (n) return (char *)str; return NULL;} const char *aa_splitn_fqname(const char *fqname, size_t n, const char **ns_name, size_t *ns_len){ const char *end = fqname + n; const char *name = skipn_spaces(fqname, n); *ns_name = NULL; *ns_len = 0; if (!name) return NULL; if (name[0] == ':') { char *split = strnchr(&name[1], end - &name[1], ':'); *ns_name = skipn_spaces(&name[1], end - &name[1]); if (!*ns_name) return NULL; if (split) { *ns_len = split - *ns_name; if (*ns_len == 0) *ns_name = NULL; split++; if (end - split > 1 && strncmp(split, "//", 2) == 0) split += 2; name = skipn_spaces(split, end - split); } else { /* a ns name without a following profile is allowed */ name = NULL; *ns_len = end - *ns_name; } } if (name && *name == 0) name = NULL; return name;} /** * aa_info_message - log a none profile related status message * @str: message to log */void aa_info_message(const char *str){ if (audit_enabled) { DEFINE_AUDIT_DATA(ad, LSM_AUDIT_DATA_NONE, AA_CLASS_NONE, NULL); ad.info = str; aa_audit_msg(AUDIT_APPARMOR_STATUS, &ad, NULL); } printk(KERN_INFO "AppArmor: %s\n", str);} __counted char *aa_str_alloc(int size, gfp_t gfp){ struct counted_str *str; str = kmalloc_flex(*str, name, size, gfp); if (!str) return NULL; kref_init(&str->count); return str->name;} void aa_str_kref(struct kref *kref){ kfree(container_of(kref, struct counted_str, count));} const char aa_file_perm_chrs[] = "xwracd km l ";const char *aa_file_perm_names[] = { "exec", "write", "read", "append", "create", "delete", "open", "rename", "setattr", "getattr", "setcred", "getcred", "chmod", "chown", "chgrp", "lock", "mmap", "mprot", "link", "snapshot", "unknown", "unknown", "unknown", "unknown", "unknown", "unknown", "unknown", "unknown", "stack", "change_onexec", "change_profile", "change_hat",}; /** * aa_perm_mask_to_str - convert a perm mask to its short string * @str: character buffer to store string in (at least 10 characters) * @str_size: size of the @str buffer * @chrs: NUL-terminated character buffer of permission characters * @mask: permission mask to convert */void aa_perm_mask_to_str(char *str, size_t str_size, const char *chrs, u32 mask){ unsigned int i, perm = 1; size_t num_chrs = strlen(chrs); for (i = 0; i < num_chrs; perm <<= 1, i++) { if (mask & perm) { /* Ensure that one byte is left for NUL-termination */ if (WARN_ON_ONCE(str_size <= 1)) break; *str++ = chrs[i]; str_size--; } } *str = '\0';} void aa_audit_perm_names(struct audit_buffer *ab, const char * const *names, u32 mask){ const char *fmt = "%s"; unsigned int i, perm = 1; bool prev = false; for (i = 0; i < 32; perm <<= 1, i++) { if (mask & perm) { audit_log_format(ab, fmt, names[i]); if (!prev) { prev = true; fmt = " %s"; } } }} void aa_audit_perm_mask(struct audit_buffer *ab, u32 mask, const char *chrs, u32 chrsmask, const char * const *names, u32 namesmask){ char str[33]; audit_log_format(ab, "\""); if ((mask & chrsmask) && chrs) { aa_perm_mask_to_str(str, sizeof(str), chrs, mask & chrsmask); mask &= ~chrsmask; audit_log_format(ab, "%s", str); if (mask & namesmask) audit_log_format(ab, " "); } if ((mask & namesmask) && names) aa_audit_perm_names(ab, names, mask & namesmask); audit_log_format(ab, "\"");} /** * aa_apply_modes_to_perms - apply namespace and profile flags to perms * @profile: that perms where computed from * @perms: perms to apply mode modifiers to * * TODO: split into profile and ns based flags for when accumulating perms */void aa_apply_modes_to_perms(struct aa_profile *profile, struct aa_perms *perms){ switch (AUDIT_MODE(profile)) { case AUDIT_ALL: perms->audit = ALL_PERMS_MASK; fallthrough; case AUDIT_NOQUIET: perms->quiet = 0; break; case AUDIT_QUIET: perms->audit = 0; fallthrough; case AUDIT_QUIET_DENIED: perms->quiet = ALL_PERMS_MASK; break; } if (KILL_MODE(profile)) perms->kill = ALL_PERMS_MASK; else if (COMPLAIN_MODE(profile)) perms->complain = ALL_PERMS_MASK; else if (USER_MODE(profile)) perms->prompt = ALL_PERMS_MASK;} void aa_profile_match_label(struct aa_profile *profile, struct aa_ruleset *rules, struct aa_label *label, int type, u32 request, struct aa_perms *perms){ /* TODO: doesn't yet handle extended types */ aa_state_t state; state = aa_dfa_next(rules->policy->dfa, rules->policy->start[AA_CLASS_LABEL], type); aa_label_match(profile, rules, label, state, false, request, perms);} /** * aa_check_perms - do audit mode selection based on perms set * @profile: profile being checked * @perms: perms computed for the request * @request: requested perms * @ad: initialized audit structure (MAY BE NULL if not auditing) * @cb: callback fn for type specific fields (MAY BE NULL) * * Returns: 0 if permission else error code * * Note: profile audit modes need to be set before calling by setting the * perm masks appropriately. * * If not auditing then complain mode is not enabled and the * error code will indicate whether there was an explicit deny * with a positive value. */int aa_check_perms(struct aa_profile *profile, struct aa_perms *perms, u32 request, struct apparmor_audit_data *ad, void (*cb)(struct audit_buffer *, void *)){ int type, error; u32 denied = request & (~perms->allow | perms->deny); if (likely(!denied)) { /* mask off perms that are not being force audited */ request &= perms->audit; if (!request || !ad) return 0; type = AUDIT_APPARMOR_AUDIT; error = 0; } else { error = -EACCES; if (denied & perms->kill) type = AUDIT_APPARMOR_KILL; else if (denied == (denied & perms->complain)) type = AUDIT_APPARMOR_ALLOWED; else type = AUDIT_APPARMOR_DENIED; if (denied == (denied & perms->hide)) error = -ENOENT; denied &= ~perms->quiet; if (!ad || !denied) return error; } if (ad) { ad->subj_label = &profile->label; ad->request = request; ad->denied = denied; ad->error = error; aa_audit_msg(type, ad, cb); } if (type == AUDIT_APPARMOR_ALLOWED) error = 0; return error;} /** * aa_policy_init - initialize a policy structure * @policy: policy to initialize (NOT NULL) * @prefix: prefix name if any is required. (MAYBE NULL) * @name: name of the policy, init will make a copy of it (NOT NULL) * @gfp: allocation mode * * Note: this fn creates a copy of strings passed in * * Returns: true if policy init successful */bool aa_policy_init(struct aa_policy *policy, const char *prefix, const char *name, gfp_t gfp){ char *hname; size_t hname_sz; hname_sz = (prefix ? strlen(prefix) + 2 : 0) + strlen(name) + 1; /* freed by policy_free */ hname = aa_str_alloc(hname_sz, gfp); if (!hname) return false; if (prefix) scnprintf(hname, hname_sz, "%s//%s", prefix, name); else strscpy(hname, name, hname_sz); policy->hname = hname; /* base.name is a substring of fqname */ policy->name = basename(policy->hname); INIT_LIST_HEAD(&policy->list); INIT_LIST_HEAD(&policy->profiles); return true;Lines 1–500 of 515. Load more
// SPDX-License-Identifier: GPL-2.0-only /* * AppArmor security module * * This file contains basic common functions used in AppArmor * * Copyright (C) 1998-2008 Novell/SUSE * Copyright 2009-2010 Canonical Ltd. */ #include <linux/ctype.h> #include <linux/mm.h> #include <linux/slab.h> #include <linux/string.h> #include <linux/vmalloc.h> #include "include/audit.h" #include "include/apparmor.h" #include "include/lib.h" #include "include/perms.h" #include "include/policy.h" struct aa_perms nullperms; struct aa_perms allperms = { .allow = ALL_PERMS_MASK, .quiet = ALL_PERMS_MASK, .hide = ALL_PERMS_MASK }; struct val_table_ent { const char *str; int value; }; static struct val_table_ent debug_values_table[] = { { "N", DEBUG_NONE }, { "none", DEBUG_NONE }, { "n", DEBUG_NONE }, { "0", DEBUG_NONE }, { "all", DEBUG_ALL }, { "Y", DEBUG_ALL }, { "y", DEBUG_ALL }, { "1", DEBUG_ALL }, { "abs_root", DEBUG_LABEL_ABS_ROOT }, { "label", DEBUG_LABEL }, { "domain", DEBUG_DOMAIN }, { "policy", DEBUG_POLICY }, { "interface", DEBUG_INTERFACE }, { "unpack", DEBUG_UNPACK }, { "tags", DEBUG_TAGS }, { NULL, 0 } }; static struct val_table_ent *val_table_find_ent(struct val_table_ent *table, const char *name, size_t len) { struct val_table_ent *entry; for (entry = table; entry->str != NULL; entry++) { if (strncmp(entry->str, name, len) == 0 && strlen(entry->str) == len) return entry; } return NULL; } int aa_parse_debug_params(const char *str) { struct val_table_ent *ent; const char *next; int val = 0; do { size_t n = strcspn(str, "\r\n,"); next = str + n; ent = val_table_find_ent(debug_values_table, str, next - str); if (ent) val |= ent->value; else AA_DEBUG(DEBUG_INTERFACE, "unknown debug type '%.*s'", (int)(next - str), str); str = next + 1; } while (*next != 0); return val; } /** * val_mask_to_str - convert a perm mask to its short string * @str: character buffer to store string in (at least 10 characters) * @size: size of the @str buffer * @table: NUL-terminated character buffer of permission characters (NOT NULL) * @mask: permission mask to convert */ static int val_mask_to_str(char *str, size_t size, const struct val_table_ent *table, u32 mask) { const struct val_table_ent *ent; int total = 0; for (ent = table; ent->str; ent++) { if (ent->value && (ent->value & mask) == ent->value) { int len = scnprintf(str, size, "%s%s", total ? "," : "", ent->str); size -= len; str += len; total += len; mask &= ~ent->value; } } return total; } int aa_print_debug_params(char *buffer) { if (!aa_g_debug) return sprintf(buffer, "N"); return val_mask_to_str(buffer, PAGE_SIZE, debug_values_table, aa_g_debug); } bool aa_resize_str_table(struct aa_str_table *t, int newsize, gfp_t gfp) { struct aa_str_table_ent *n; int i; if (t->size == newsize) return true; n = kzalloc_objs(*n, newsize, gfp); if (!n) return false; for (i = 0; i < min(t->size, newsize); i++) n[i] = t->table[i]; for (; i < t->size; i++) kfree_sensitive(t->table[i].strs); if (newsize > t->size) memset(&n[t->size], 0, (newsize-t->size)*sizeof(*n)); kfree_sensitive(t->table); t->table = n; t->size = newsize; return true; } /** * aa_destroy_str_table - free entries str table * @t: the string table to free (MAYBE NULL) */ void aa_destroy_str_table(struct aa_str_table *t) { int i; if (t) { if (!t->table) return; for (i = 0; i < t->size; i++) kfree_sensitive(t->table[i].strs); kfree_sensitive(t->table); t->table = NULL; t->size = 0; } } /** * skipn_spaces - Removes leading whitespace from @str. * @str: The string to be stripped. * @n: length of str to parse, will stop at \0 if encountered before n * * Returns a pointer to the first non-whitespace character in @str. * if all whitespace will return NULL */ const char *skipn_spaces(const char *str, size_t n) { for (; n && isspace(*str); --n) ++str; if (n) return (char *)str; return NULL; } const char *aa_splitn_fqname(const char *fqname, size_t n, const char **ns_name, size_t *ns_len) { const char *end = fqname + n; const char *name = skipn_spaces(fqname, n); *ns_name = NULL; *ns_len = 0; if (!name) return NULL; if (name[0] == ':') { char *split = strnchr(&name[1], end - &name[1], ':'); *ns_name = skipn_spaces(&name[1], end - &name[1]); if (!*ns_name) return NULL; if (split) { *ns_len = split - *ns_name; if (*ns_len == 0) *ns_name = NULL; split++; if (end - split > 1 && strncmp(split, "//", 2) == 0) split += 2; name = skipn_spaces(split, end - split); } else { /* a ns name without a following profile is allowed */ name = NULL; *ns_len = end - *ns_name; } } if (name && *name == 0) name = NULL; return name; } /** * aa_info_message - log a none profile related status message * @str: message to log */ void aa_info_message(const char *str) { if (audit_enabled) { DEFINE_AUDIT_DATA(ad, LSM_AUDIT_DATA_NONE, AA_CLASS_NONE, NULL); ad.info = str; aa_audit_msg(AUDIT_APPARMOR_STATUS, &ad, NULL); } printk(KERN_INFO "AppArmor: %s\n", str); } __counted char *aa_str_alloc(int size, gfp_t gfp) { struct counted_str *str; str = kmalloc_flex(*str, name, size, gfp); if (!str) return NULL; kref_init(&str->count); return str->name; } void aa_str_kref(struct kref *kref) { kfree(container_of(kref, struct counted_str, count)); } const char aa_file_perm_chrs[] = "xwracd km l "; const char *aa_file_perm_names[] = { "exec", "write", "read", "append", "create", "delete", "open", "rename", "setattr", "getattr", "setcred", "getcred", "chmod", "chown", "chgrp", "lock", "mmap", "mprot", "link", "snapshot", "unknown", "unknown", "unknown", "unknown", "unknown", "unknown", "unknown", "unknown", "stack", "change_onexec", "change_profile", "change_hat", }; /** * aa_perm_mask_to_str - convert a perm mask to its short string * @str: character buffer to store string in (at least 10 characters) * @str_size: size of the @str buffer * @chrs: NUL-terminated character buffer of permission characters * @mask: permission mask to convert */ void aa_perm_mask_to_str(char *str, size_t str_size, const char *chrs, u32 mask) { unsigned int i, perm = 1; size_t num_chrs = strlen(chrs); for (i = 0; i < num_chrs; perm <<= 1, i++) { if (mask & perm) { /* Ensure that one byte is left for NUL-termination */ if (WARN_ON_ONCE(str_size <= 1)) break; *str++ = chrs[i]; str_size--; } } *str = '\0'; } void aa_audit_perm_names(struct audit_buffer *ab, const char * const *names, u32 mask) { const char *fmt = "%s"; unsigned int i, perm = 1; bool prev = false; for (i = 0; i < 32; perm <<= 1, i++) { if (mask & perm) { audit_log_format(ab, fmt, names[i]); if (!prev) { prev = true; fmt = " %s"; } } } } void aa_audit_perm_mask(struct audit_buffer *ab, u32 mask, const char *chrs, u32 chrsmask, const char * const *names, u32 namesmask) { char str[33]; audit_log_format(ab, "\""); if ((mask & chrsmask) && chrs) { aa_perm_mask_to_str(str, sizeof(str), chrs, mask & chrsmask); mask &= ~chrsmask; audit_log_format(ab, "%s", str); if (mask & namesmask) audit_log_format(ab, " "); } if ((mask & namesmask) && names) aa_audit_perm_names(ab, names, mask & namesmask); audit_log_format(ab, "\""); } /** * aa_apply_modes_to_perms - apply namespace and profile flags to perms * @profile: that perms where computed from * @perms: perms to apply mode modifiers to * * TODO: split into profile and ns based flags for when accumulating perms */ void aa_apply_modes_to_perms(struct aa_profile *profile, struct aa_perms *perms) { switch (AUDIT_MODE(profile)) { case AUDIT_ALL: perms->audit = ALL_PERMS_MASK; fallthrough; case AUDIT_NOQUIET: perms->quiet = 0; break; case AUDIT_QUIET: perms->audit = 0; fallthrough; case AUDIT_QUIET_DENIED: perms->quiet = ALL_PERMS_MASK; break; } if (KILL_MODE(profile)) perms->kill = ALL_PERMS_MASK; else if (COMPLAIN_MODE(profile)) perms->complain = ALL_PERMS_MASK; else if (USER_MODE(profile)) perms->prompt = ALL_PERMS_MASK; } void aa_profile_match_label(struct aa_profile *profile, struct aa_ruleset *rules, struct aa_label *label, int type, u32 request, struct aa_perms *perms) { /* TODO: doesn't yet handle extended types */ aa_state_t state; state = aa_dfa_next(rules->policy->dfa, rules->policy->start[AA_CLASS_LABEL], type); aa_label_match(profile, rules, label, state, false, request, perms); } /** * aa_check_perms - do audit mode selection based on perms set * @profile: profile being checked * @perms: perms computed for the request * @request: requested perms * @ad: initialized audit structure (MAY BE NULL if not auditing) * @cb: callback fn for type specific fields (MAY BE NULL) * * Returns: 0 if permission else error code * * Note: profile audit modes need to be set before calling by setting the * perm masks appropriately. * * If not auditing then complain mode is not enabled and the * error code will indicate whether there was an explicit deny * with a positive value. */ int aa_check_perms(struct aa_profile *profile, struct aa_perms *perms, u32 request, struct apparmor_audit_data *ad, void (*cb)(struct audit_buffer *, void *)) { int type, error; u32 denied = request & (~perms->allow | perms->deny); if (likely(!denied)) { /* mask off perms that are not being force audited */ request &= perms->audit; if (!request || !ad) return 0; type = AUDIT_APPARMOR_AUDIT; error = 0; } else { error = -EACCES; if (denied & perms->kill) type = AUDIT_APPARMOR_KILL; else if (denied == (denied & perms->complain)) type = AUDIT_APPARMOR_ALLOWED; else type = AUDIT_APPARMOR_DENIED; if (denied == (denied & perms->hide)) error = -ENOENT; denied &= ~perms->quiet; if (!ad || !denied) return error; } if (ad) { ad->subj_label = &profile->label; ad->request = request; ad->denied = denied; ad->error = error; aa_audit_msg(type, ad, cb); } if (type == AUDIT_APPARMOR_ALLOWED) error = 0; return error; } /** * aa_policy_init - initialize a policy structure * @policy: policy to initialize (NOT NULL) * @prefix: prefix name if any is required. (MAYBE NULL) * @name: name of the policy, init will make a copy of it (NOT NULL) * @gfp: allocation mode * * Note: this fn creates a copy of strings passed in * * Returns: true if policy init successful */ bool aa_policy_init(struct aa_policy *policy, const char *prefix, const char *name, gfp_t gfp) { char *hname; size_t hname_sz; hname_sz = (prefix ? strlen(prefix) + 2 : 0) + strlen(name) + 1; /* freed by policy_free */ hname = aa_str_alloc(hname_sz, gfp); if (!hname) return false; if (prefix) scnprintf(hname, hname_sz, "%s//%s", prefix, name); else strscpy(hname, name, hname_sz); policy->hname = hname; /* base.name is a substring of fqname */ policy->name = basename(policy->hname); INIT_LIST_HEAD(&policy->list); INIT_LIST_HEAD(&policy->profiles); return true;