From ae581a19fbe896a797450b9d9573fb66f2735227 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 16:37:38 +0200 Subject: Adding upstream version 1.9.13p3. Signed-off-by: Daniel Baumann --- plugins/sudoers/alias.c | 377 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 377 insertions(+) create mode 100644 plugins/sudoers/alias.c (limited to 'plugins/sudoers/alias.c') diff --git a/plugins/sudoers/alias.c b/plugins/sudoers/alias.c new file mode 100644 index 0000000..d435400 --- /dev/null +++ b/plugins/sudoers/alias.c @@ -0,0 +1,377 @@ +/* + * SPDX-License-Identifier: ISC + * + * Copyright (c) 2004-2005, 2007-2019 + * Todd C. Miller + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +/* + * This is an open source non-commercial project. Dear PVS-Studio, please check it. + * PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com + */ + +/* + * This is an open source non-commercial project. Dear PVS-Studio, please check it. + * PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com + */ + +#include + +#include +#include +#include +#include + +#include "sudoers.h" +#include "redblack.h" +#include + +/* + * Comparison function for the red-black tree. + * Aliases are sorted by name with the type used as a tie-breaker. + */ +static int +alias_compare(const void *v1, const void *v2) +{ + const struct alias *a1 = (const struct alias *)v1; + const struct alias *a2 = (const struct alias *)v2; + int res; + debug_decl(alias_compare, SUDOERS_DEBUG_ALIAS); + + if (a1 == NULL) + res = -1; + else if (a2 == NULL) + res = 1; + else if ((res = strcmp(a1->name, a2->name)) == 0) + res = a1->type - a2->type; + debug_return_int(res); +} + +/* + * Search the tree for an alias with the specified name and type. + * Returns a pointer to the alias structure or NULL if not found. + * Caller is responsible for calling alias_put() on the returned + * alias to mark it as unused. + */ +struct alias * +alias_get(struct sudoers_parse_tree *parse_tree, const char *name, int type) +{ + struct alias key; + struct rbnode *node; + struct alias *a = NULL; + debug_decl(alias_get, SUDOERS_DEBUG_ALIAS); + + if (parse_tree->aliases == NULL) + debug_return_ptr(NULL); + + key.name = (char *)name; + key.type = type; + if ((node = rbfind(parse_tree->aliases, &key)) != NULL) { + /* + * Check whether this alias is already in use. + * If so, we've detected a loop. If not, set the flag, + * which the caller should clear with a call to alias_put(). + */ + a = node->data; + if (a->used) { + errno = ELOOP; + debug_return_ptr(NULL); + } + a->used = true; + } else { + errno = ENOENT; + } + debug_return_ptr(a); +} + +/* + * Clear the "used" flag in an alias once the caller is done with it. + */ +void +alias_put(struct alias *a) +{ + debug_decl(alias_put, SUDOERS_DEBUG_ALIAS); + a->used = false; + debug_return; +} + +/* + * Add an alias to the aliases redblack tree. + * Note that "file" must be a reference-counted string. + * Returns true on success and false on failure, setting errno. + */ +bool +alias_add(struct sudoers_parse_tree *parse_tree, char *name, int type, + char *file, int line, int column, struct member *members) +{ + struct alias *a; + debug_decl(alias_add, SUDOERS_DEBUG_ALIAS); + + if (parse_tree->aliases == NULL) { + if ((parse_tree->aliases = alloc_aliases()) == NULL) + debug_return_bool(false); + } + + a = calloc(1, sizeof(*a)); + if (a == NULL) + debug_return_bool(false); + + /* Only set elements used by alias_compare() in case there is a dupe. */ + a->name = name; + a->type = type; + switch (rbinsert(parse_tree->aliases, a, NULL)) { + case 1: + free(a); + errno = EEXIST; + debug_return_bool(false); + case -1: + free(a); + debug_return_bool(false); + } + + /* + * It is now safe to fill in the rest of the alias. We do this last + * since it modifies "file" (adds a ref) and "members" (tailq conversion). + */ + /* a->used = false; */ + a->file = sudo_rcstr_addref(file); + a->line = line; + a->column = column; + HLTQ_TO_TAILQ(&a->members, members, entries); + debug_return_bool(true); +} + +/* + * Closure to adapt 2-arg rbapply() to 3-arg alias_apply(). + */ +struct alias_apply_closure { + struct sudoers_parse_tree *parse_tree; + int (*func)(struct sudoers_parse_tree *, struct alias *, void *); + void *cookie; +}; + +/* Adapt rbapply() to alias_apply() calling convention. */ +static int +alias_apply_func(void *v1, void *v2) +{ + struct alias *a = v1; + struct alias_apply_closure *closure = v2; + + return closure->func(closure->parse_tree, a, closure->cookie); +} + +/* + * Apply a function to each alias entry and pass in a cookie. + */ +void +alias_apply(struct sudoers_parse_tree *parse_tree, + int (*func)(struct sudoers_parse_tree *, struct alias *, void *), + void *cookie) +{ + struct alias_apply_closure closure; + debug_decl(alias_apply, SUDOERS_DEBUG_ALIAS); + + if (parse_tree->aliases != NULL) { + closure.parse_tree = parse_tree; + closure.func = func; + closure.cookie = cookie; + rbapply(parse_tree->aliases, alias_apply_func, &closure, inorder); + } + + debug_return; +} + +/* + * Returns true if there are no aliases in the parse_tree, else false. + */ +bool +no_aliases(struct sudoers_parse_tree *parse_tree) +{ + debug_decl(no_aliases, SUDOERS_DEBUG_ALIAS); + debug_return_bool(parse_tree->aliases == NULL || + rbisempty(parse_tree->aliases)); +} + +/* + * Free memory used by an alias struct and its members. + */ +void +alias_free(void *v) +{ + struct alias *a = (struct alias *)v; + debug_decl(alias_free, SUDOERS_DEBUG_ALIAS); + + if (a != NULL) { + free(a->name); + sudo_rcstr_delref(a->file); + free_members(&a->members); + free(a); + } + + debug_return; +} + +/* + * Find the named alias, remove it from the tree and return it. + */ +struct alias * +alias_remove(struct sudoers_parse_tree *parse_tree, const char *name, int type) +{ + struct rbnode *node; + struct alias key; + debug_decl(alias_remove, SUDOERS_DEBUG_ALIAS); + + if (parse_tree->aliases != NULL) { + key.name = (char *)name; + key.type = type; + if ((node = rbfind(parse_tree->aliases, &key)) != NULL) + debug_return_ptr(rbdelete(parse_tree->aliases, node)); + } + errno = ENOENT; + debug_return_ptr(NULL); +} + +struct rbtree * +alloc_aliases(void) +{ + debug_decl(alloc_aliases, SUDOERS_DEBUG_ALIAS); + + debug_return_ptr(rbcreate(alias_compare)); +} + +void +free_aliases(struct rbtree *aliases) +{ + debug_decl(free_aliases, SUDOERS_DEBUG_ALIAS); + + if (aliases != NULL) + rbdestroy(aliases, alias_free); +} + +const char * +alias_type_to_string(int alias_type) +{ + return alias_type == HOSTALIAS ? "Host_Alias" : + alias_type == CMNDALIAS ? "Cmnd_Alias" : + alias_type == USERALIAS ? "User_Alias" : + alias_type == RUNASALIAS ? "Runas_Alias" : + "Invalid_Alias"; +} + +/* + * Remove the alias of the specified type as well as any other aliases + * referenced by that alias. Stores removed aliases in a freelist. + */ +static bool +alias_remove_recursive(struct sudoers_parse_tree *parse_tree, char *name, + int type, struct rbtree *freelist) +{ + struct member *m; + struct alias *a; + bool ret = true; + debug_decl(alias_remove_recursive, SUDOERS_DEBUG_ALIAS); + + if ((a = alias_remove(parse_tree, name, type)) != NULL) { + TAILQ_FOREACH(m, &a->members, entries) { + if (m->type == ALIAS) { + if (!alias_remove_recursive(parse_tree, m->name, type, freelist)) + ret = false; + } + } + if (rbinsert(freelist, a, NULL) != 0) + ret = false; + } + debug_return_bool(ret); +} + +static int +alias_find_used_members(struct sudoers_parse_tree *parse_tree, + struct member_list *members, int atype, struct rbtree *used_aliases) +{ + struct member *m; + int errors = 0; + debug_decl(alias_find_used_members, SUDOERS_DEBUG_ALIAS); + + if (members != NULL) { + TAILQ_FOREACH(m, members, entries) { + if (m->type != ALIAS) + continue; + if (!alias_remove_recursive(parse_tree, m->name, atype, used_aliases)) + errors++; + } + } + + debug_return_int(errors); +} + +/* + * Move all aliases referenced by userspecs to used_aliases. + */ +bool +alias_find_used(struct sudoers_parse_tree *parse_tree, struct rbtree *used_aliases) +{ + struct privilege *priv; + struct userspec *us; + struct cmndspec *cs; + struct defaults *d; + struct member *m; + int errors = 0; + debug_decl(alias_find_used, SUDOERS_DEBUG_ALIAS); + + /* Move referenced aliases to used_aliases. */ + TAILQ_FOREACH(us, &parse_tree->userspecs, entries) { + errors += alias_find_used_members(parse_tree, &us->users, + USERALIAS, used_aliases); + TAILQ_FOREACH(priv, &us->privileges, entries) { + errors += alias_find_used_members(parse_tree, &priv->hostlist, + HOSTALIAS, used_aliases); + TAILQ_FOREACH(cs, &priv->cmndlist, entries) { + errors += alias_find_used_members(parse_tree, cs->runasuserlist, + RUNASALIAS, used_aliases); + errors += alias_find_used_members(parse_tree, cs->runasgrouplist, + RUNASALIAS, used_aliases); + if ((m = cs->cmnd)->type == ALIAS) { + if (!alias_remove_recursive(parse_tree, m->name, CMNDALIAS, + used_aliases)) + errors++; + } + } + } + } + TAILQ_FOREACH(d, &parse_tree->defaults, entries) { + switch (d->type) { + case DEFAULTS_HOST: + errors += alias_find_used_members(parse_tree, + &d->binding->members, HOSTALIAS, used_aliases); + break; + case DEFAULTS_USER: + errors += alias_find_used_members(parse_tree, + &d->binding->members, USERALIAS, used_aliases); + break; + case DEFAULTS_RUNAS: + errors += alias_find_used_members(parse_tree, + &d->binding->members, RUNASALIAS, used_aliases); + break; + case DEFAULTS_CMND: + errors += alias_find_used_members(parse_tree, + &d->binding->members, CMNDALIAS, used_aliases); + break; + default: + break; + } + } + + debug_return_int(errors ? false : true); +} -- cgit v1.2.3