diff options
Diffstat (limited to 'src/lib/confmgt')
| -rw-r--r-- | src/lib/confmgt/.may_include | 12 | ||||
| -rw-r--r-- | src/lib/confmgt/confmgt.c | 1406 | ||||
| -rw-r--r-- | src/lib/confmgt/confmgt.h | 136 | ||||
| -rw-r--r-- | src/lib/confmgt/include.am | 27 | ||||
| -rw-r--r-- | src/lib/confmgt/lib_confmgt.md | 7 | ||||
| -rw-r--r-- | src/lib/confmgt/structvar.c | 239 | ||||
| -rw-r--r-- | src/lib/confmgt/structvar.h | 54 | ||||
| -rw-r--r-- | src/lib/confmgt/type_defs.c | 849 | ||||
| -rw-r--r-- | src/lib/confmgt/type_defs.h | 17 | ||||
| -rw-r--r-- | src/lib/confmgt/typedvar.c | 236 | ||||
| -rw-r--r-- | src/lib/confmgt/typedvar.h | 38 | ||||
| -rw-r--r-- | src/lib/confmgt/unitparse.c | 260 | ||||
| -rw-r--r-- | src/lib/confmgt/unitparse.h | 35 | ||||
| -rw-r--r-- | src/lib/confmgt/var_type_def_st.h | 167 |
14 files changed, 3483 insertions, 0 deletions
diff --git a/src/lib/confmgt/.may_include b/src/lib/confmgt/.may_include new file mode 100644 index 0000000000..5ff949f103 --- /dev/null +++ b/src/lib/confmgt/.may_include @@ -0,0 +1,12 @@ +orconfig.h +lib/cc/*.h +lib/conf/*.h +lib/confmgt/*.h +lib/container/*.h +lib/encoding/*.h +lib/intmath/*.h +lib/log/*.h +lib/malloc/*.h +lib/string/*.h +lib/testsupport/*.h +ext/*.h diff --git a/src/lib/confmgt/confmgt.c b/src/lib/confmgt/confmgt.c new file mode 100644 index 0000000000..bf2764160e --- /dev/null +++ b/src/lib/confmgt/confmgt.c @@ -0,0 +1,1406 @@ +/* Copyright (c) 2001 Matej Pfajfar. + * Copyright (c) 2001-2004, Roger Dingledine. + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2020, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * \file confmgt.c + * + * \brief Back-end for parsing and generating key-value files, used to + * implement the torrc file format and the state file. + * + * This module is used by config.c to parse and encode torrc + * configuration files, and by statefile.c to parse and encode the + * $DATADIR/state file. + * + * To use this module, its callers provide an instance of + * config_format_t to describe the mappings from a set of configuration + * options to a number of fields in a C structure. With this mapping, + * the functions here can convert back and forth between the C structure + * specified, and a linked list of key-value pairs. + */ + +#define CONFMGT_PRIVATE +#include "orconfig.h" +#include "lib/confmgt/confmgt.h" + +#include "lib/confmgt/structvar.h" +#include "lib/confmgt/unitparse.h" +#include "lib/container/bitarray.h" +#include "lib/container/smartlist.h" +#include "lib/encoding/confline.h" +#include "lib/log/escape.h" +#include "lib/log/log.h" +#include "lib/log/util_bug.h" +#include "lib/string/compat_ctype.h" +#include "lib/string/printf.h" +#include "lib/string/util_string.h" + +#include "ext/siphash.h" + +/** + * A managed_var_t is an internal wrapper around a config_var_t in + * a config_format_t structure. It is used by config_mgr_t to + * keep track of which option goes with which structure. */ +typedef struct managed_var_t { + /** + * A pointer to the config_var_t for this option. + */ + const config_var_t *cvar; + /** + * The index of the object in which this option is stored. It is + * IDX_TOPLEVEL to indicate that the object is the top-level object. + **/ + int object_idx; +} managed_var_t; + +static void config_reset(const config_mgr_t *fmt, void *options, + const managed_var_t *var, int use_defaults); +static void config_mgr_register_fmt(config_mgr_t *mgr, + const config_format_t *fmt, + int object_idx); + +/** Release all storage held in a managed_var_t. */ +static void +managed_var_free_(managed_var_t *mv) +{ + if (!mv) + return; + tor_free(mv); +} +#define managed_var_free(mv) \ + FREE_AND_NULL(managed_var_t, managed_var_free_, (mv)) + +struct config_suite_t { + /** A list of configuration objects managed by a given configuration + * manager. They are stored in the same order as the config_format_t + * objects in the manager's list of subformats. */ + smartlist_t *configs; +}; + +/** + * Allocate a new empty config_suite_t. + **/ +static config_suite_t * +config_suite_new(void) +{ + config_suite_t *suite = tor_malloc_zero(sizeof(config_suite_t)); + suite->configs = smartlist_new(); + return suite; +} + +/** Release all storage held by a config_suite_t. (Does not free + * any configuration objects it holds; the caller must do that first.) */ +static void +config_suite_free_(config_suite_t *suite) +{ + if (!suite) + return; + smartlist_free(suite->configs); + tor_free(suite); +} + +#define config_suite_free(suite) \ + FREE_AND_NULL(config_suite_t, config_suite_free_, (suite)) + +struct config_mgr_t { + /** The 'top-level' configuration format. This one is used for legacy + * options that have not yet been assigned to different sub-modules. + * + * (NOTE: for now, this is the only config_format_t that a config_mgr_t + * contains. A subsequent commit will add more. XXXX) + */ + const config_format_t *toplevel; + /** + * List of second-level configuration format objects that this manager + * also knows about. + */ + smartlist_t *subconfigs; + /** A smartlist of managed_var_t objects for all configuration formats. */ + smartlist_t *all_vars; + /** A smartlist of config_abbrev_t objects for all configuration + * formats. These objects are used to track synonyms and abbreviations for + * different configuration options. */ + smartlist_t *all_abbrevs; + /** A smartlist of config_deprecation_t for all configuration formats. */ + smartlist_t *all_deprecations; + /** True if this manager has been frozen and cannot have any more formats + * added to it. A manager must be frozen before it can be used to construct + * or manipulate objects. */ + bool frozen; + /** A replacement for the magic number of the toplevel object. We override + * that number to make it unique for this particular config_mgr_t, so that + * an object constructed with one mgr can't be used with another, even if + * those managers' contents are equal. + */ + struct_magic_decl_t toplevel_magic; +}; + +#define IDX_TOPLEVEL (-1) + +/** Create a new config_mgr_t to manage a set of configuration objects to be + * wrapped under <b>toplevel_fmt</b>. */ +config_mgr_t * +config_mgr_new(const config_format_t *toplevel_fmt) +{ + config_mgr_t *mgr = tor_malloc_zero(sizeof(config_mgr_t)); + mgr->subconfigs = smartlist_new(); + mgr->all_vars = smartlist_new(); + mgr->all_abbrevs = smartlist_new(); + mgr->all_deprecations = smartlist_new(); + + config_mgr_register_fmt(mgr, toplevel_fmt, IDX_TOPLEVEL); + mgr->toplevel = toplevel_fmt; + + return mgr; +} + +/** Add a config_format_t to a manager, with a specified (unique) index. */ +static void +config_mgr_register_fmt(config_mgr_t *mgr, + const config_format_t *fmt, + int object_idx) +{ + int i; + + tor_assertf(!mgr->frozen, + "Tried to add a format to a configuration manager after " + "it had been frozen."); + + if (object_idx != IDX_TOPLEVEL) { + tor_assertf(! fmt->has_config_suite, + "Tried to register a toplevel format in a non-toplevel position"); + } + if (fmt->config_suite_offset) { + tor_assertf(fmt->has_config_suite, + "config_suite_offset was set, but has_config_suite was not."); + } + + tor_assertf(fmt != mgr->toplevel && + ! smartlist_contains(mgr->subconfigs, fmt), + "Tried to register an already-registered format."); + + /* register variables */ + for (i = 0; fmt->vars[i].member.name; ++i) { + managed_var_t *mv = tor_malloc_zero(sizeof(managed_var_t)); + mv->cvar = &fmt->vars[i]; + mv->object_idx = object_idx; + smartlist_add(mgr->all_vars, mv); + } + + /* register abbrevs */ + if (fmt->abbrevs) { + for (i = 0; fmt->abbrevs[i].abbreviated; ++i) { + smartlist_add(mgr->all_abbrevs, (void*)&fmt->abbrevs[i]); + } + } + + /* register deprecations. */ + if (fmt->deprecations) { + const config_deprecation_t *d; + for (d = fmt->deprecations; d->name; ++d) { + smartlist_add(mgr->all_deprecations, (void*)d); + } + } +} + +/** + * Add a new format to this configuration object. Asserts on failure. + * + * Returns an internal "index" value used to identify this format within + * all of those formats contained in <b>mgr</b>. This index value + * should not generally be used outside of this module. + **/ +int +config_mgr_add_format(config_mgr_t *mgr, + const config_format_t *fmt) +{ + tor_assert(mgr); + int idx = smartlist_len(mgr->subconfigs); + config_mgr_register_fmt(mgr, fmt, idx); + smartlist_add(mgr->subconfigs, (void *)fmt); + return idx; +} + +/** Return a pointer to the config_suite_t * pointer inside a + * configuration object; returns NULL if there is no such member. */ +static inline config_suite_t ** +config_mgr_get_suite_ptr(const config_mgr_t *mgr, void *toplevel) +{ + if (! mgr->toplevel->has_config_suite) + return NULL; + return STRUCT_VAR_P(toplevel, mgr->toplevel->config_suite_offset); +} + +/** + * Return a pointer to the configuration object within <b>toplevel</b> whose + * index is <b>idx</b>. + * + * NOTE: XXXX Eventually, there will be multiple objects supported within the + * toplevel object. For example, the or_options_t will contain pointers + * to configuration objects for other modules. This function gets + * the sub-object for a particular module. + */ +void * +config_mgr_get_obj_mutable(const config_mgr_t *mgr, void *toplevel, int idx) +{ + tor_assert(mgr); + tor_assert(toplevel); + if (idx == IDX_TOPLEVEL) + return toplevel; + + tor_assertf(idx >= 0 && idx < smartlist_len(mgr->subconfigs), + "Index %d is out of range.", idx); + config_suite_t **suite = config_mgr_get_suite_ptr(mgr, toplevel); + tor_assert(suite); + tor_assert(smartlist_len(mgr->subconfigs) == + smartlist_len((*suite)->configs)); + + return smartlist_get((*suite)->configs, idx); +} + +/** As config_mgr_get_obj_mutable(), but return a const pointer. */ +const void * +config_mgr_get_obj(const config_mgr_t *mgr, const void *toplevel, int idx) +{ + return config_mgr_get_obj_mutable(mgr, (void*)toplevel, idx); +} + +/** Sorting helper for smartlist of managed_var_t */ +static int +managed_var_cmp(const void **a, const void **b) +{ + const managed_var_t *mv1 = *(const managed_var_t**)a; + const managed_var_t *mv2 = *(const managed_var_t**)b; + + return strcasecmp(mv1->cvar->member.name, mv2->cvar->member.name); +} + +/** + * Mark a configuration manager as "frozen", so that no more formats can be + * added, and so that it can be used for manipulating configuration objects. + **/ +void +config_mgr_freeze(config_mgr_t *mgr) +{ + static uint64_t mgr_count = 0; + + smartlist_sort(mgr->all_vars, managed_var_cmp); + memcpy(&mgr->toplevel_magic, &mgr->toplevel->magic, + sizeof(struct_magic_decl_t)); + uint64_t magic_input[3] = { mgr->toplevel_magic.magic_val, + (uint64_t) (uintptr_t) mgr, + ++mgr_count }; + mgr->toplevel_magic.magic_val = + (uint32_t)siphash24g(magic_input, sizeof(magic_input)); + mgr->frozen = true; +} + +/** Release all storage held in <b>mgr</b> */ +void +config_mgr_free_(config_mgr_t *mgr) +{ + if (!mgr) + return; + SMARTLIST_FOREACH(mgr->all_vars, managed_var_t *, mv, managed_var_free(mv)); + smartlist_free(mgr->all_vars); + smartlist_free(mgr->all_abbrevs); + smartlist_free(mgr->all_deprecations); + smartlist_free(mgr->subconfigs); + memset(mgr, 0, sizeof(*mgr)); + tor_free(mgr); +} + +/** Return a new smartlist_t containing a config_var_t for every variable that + * <b>mgr</b> knows about. The elements of this smartlist do not need + * to be freed; they have the same lifespan as <b>mgr</b>. */ +smartlist_t * +config_mgr_list_vars(const config_mgr_t *mgr) +{ + smartlist_t *result = smartlist_new(); + tor_assert(mgr); + SMARTLIST_FOREACH(mgr->all_vars, managed_var_t *, mv, + smartlist_add(result, (void*) mv->cvar)); + return result; +} + +/** Return a new smartlist_t containing the names of all deprecated variables. + * The elements of this smartlist do not need to be freed; they have the same + * lifespan as <b>mgr</b>. + */ +smartlist_t * +config_mgr_list_deprecated_vars(const config_mgr_t *mgr) +{ + smartlist_t *result = smartlist_new(); + tor_assert(mgr); + SMARTLIST_FOREACH(mgr->all_deprecations, config_deprecation_t *, d, + smartlist_add(result, (char*)d->name)); + return result; +} + +/** + * Check the magic number on <b>object</b> to make sure it's a valid toplevel + * object, created with <b>mgr</b>. Exit with an assertion if it isn't. + **/ +void +config_check_toplevel_magic(const config_mgr_t *mgr, + const void *object) +{ + struct_check_magic(object, &mgr->toplevel_magic); +} + +/** Assert that the magic fields in <b>options</b> and its subsidiary + * objects are all okay. */ +static void +config_mgr_assert_magic_ok(const config_mgr_t *mgr, + const void *options) +{ + tor_assert(mgr); + tor_assert(options); + tor_assert(mgr->frozen); + struct_check_magic(options, &mgr->toplevel_magic); + + config_suite_t **suitep = config_mgr_get_suite_ptr(mgr, (void*)options); + if (suitep == NULL) { + tor_assert(smartlist_len(mgr->subconfigs) == 0); + return; + } + + tor_assert(smartlist_len((*suitep)->configs) == + smartlist_len(mgr->subconfigs)); + SMARTLIST_FOREACH_BEGIN(mgr->subconfigs, const config_format_t *, fmt) { + void *obj = smartlist_get((*suitep)->configs, fmt_sl_idx); + tor_assert(obj); + struct_check_magic(obj, &fmt->magic); + } SMARTLIST_FOREACH_END(fmt); +} + +/** Macro: assert that <b>cfg</b> has the right magic field for + * <b>mgr</b>. */ +#define CONFIG_CHECK(mgr, cfg) STMT_BEGIN \ + config_mgr_assert_magic_ok((mgr), (cfg)); \ + STMT_END + +/** Allocate an empty configuration object of a given format type. */ +void * +config_new(const config_mgr_t *mgr) +{ + tor_assert(mgr->frozen); + void *opts = tor_malloc_zero(mgr->toplevel->size); + struct_set_magic(opts, &mgr->toplevel_magic); + config_suite_t **suitep = config_mgr_get_suite_ptr(mgr, opts); + if (suitep) { + *suitep = config_suite_new(); + SMARTLIST_FOREACH_BEGIN(mgr->subconfigs, const config_format_t *, fmt) { + void *obj = tor_malloc_zero(fmt->size); + struct_set_magic(obj, &fmt->magic); + smartlist_add((*suitep)->configs, obj); + } SMARTLIST_FOREACH_END(fmt); + } + CONFIG_CHECK(mgr, opts); + return opts; +} + +/* + * Functions to parse config options + */ + +/** If <b>option</b> is an official abbreviation for a longer option, + * return the longer option. Otherwise return <b>option</b>. + * If <b>command_line</b> is set, apply all abbreviations. Otherwise, only + * apply abbreviations that work for the config file and the command line. + * If <b>warn_obsolete</b> is set, warn about deprecated names. */ +const char * +config_expand_abbrev(const config_mgr_t *mgr, const char *option, + int command_line, int warn_obsolete) +{ + SMARTLIST_FOREACH_BEGIN(mgr->all_abbrevs, const config_abbrev_t *, abbrev) { + /* Abbreviations are case insensitive. */ + if (!strcasecmp(option, abbrev->abbreviated) && + (command_line || !abbrev->commandline_only)) { + if (warn_obsolete && abbrev->warn) { + log_warn(LD_CONFIG, + "The configuration option '%s' is deprecated; " + "use '%s' instead.", + abbrev->abbreviated, + abbrev->full); + } + /* Keep going through the list in case we want to rewrite it more. + * (We could imagine recursing here, but I don't want to get the + * user into an infinite loop if we craft our list wrong.) */ + option = abbrev->full; + } + } SMARTLIST_FOREACH_END(abbrev); + return option; +} + +/** If <b>key</b> is a deprecated configuration option, return the message + * explaining why it is deprecated (which may be an empty string). Return NULL + * if it is not deprecated. The <b>key</b> field must be fully expanded. */ +const char * +config_find_deprecation(const config_mgr_t *mgr, const char *key) +{ + if (BUG(mgr == NULL) || BUG(key == NULL)) + return NULL; // LCOV_EXCL_LINE + + SMARTLIST_FOREACH_BEGIN(mgr->all_deprecations, const config_deprecation_t *, + d) { + if (!strcasecmp(d->name, key)) { + return d->why_deprecated ? d->why_deprecated : ""; + } + } SMARTLIST_FOREACH_END(d); + return NULL; +} + +/** + * Find the managed_var_t object for a variable whose name is <b>name</b> + * according to <b>mgr</b>. Return that object, or NULL if none exists. + * + * If <b>allow_truncated</b> is true, then accept any variable whose + * name begins with <b>name</b>. + * + * If <b>idx_out</b> is not NULL, set *<b>idx_out</b> to the position of + * that variable within mgr->all_vars, or to -1 if the variable is + * not found. + */ +static const managed_var_t * +config_mgr_find_var(const config_mgr_t *mgr, + const char *key, + bool allow_truncated, int *idx_out) +{ + const size_t keylen = strlen(key); + if (idx_out) + *idx_out = -1; + + if (!keylen) + return NULL; /* if they say "--" on the command line, it's not an option */ + + /* First, check for an exact (case-insensitive) match */ + SMARTLIST_FOREACH_BEGIN(mgr->all_vars, const managed_var_t *, mv) { + if (!strcasecmp(mv->cvar->member.name, key)) { + if (idx_out) + *idx_out = mv_sl_idx; + return mv; + } + } SMARTLIST_FOREACH_END(mv); + + if (!allow_truncated) + return NULL; + + /* If none, check for an abbreviated match */ + SMARTLIST_FOREACH_BEGIN(mgr->all_vars, const managed_var_t *, mv) { + if (!strncasecmp(key, mv->cvar->member.name, keylen)) { + log_warn(LD_CONFIG, "The abbreviation '%s' is deprecated. " + "Please use '%s' instead", + key, mv->cvar->member.name); + if (idx_out) + *idx_out = mv_sl_idx; + return mv; + } + } SMARTLIST_FOREACH_END(mv); + + /* Okay, unrecognized option */ + return NULL; +} + +/** + * If <b>key</b> is a name or an abbreviation configuration option, return + * the corresponding canonical name for it. Warn if the abbreviation is + * non-standard. Return NULL if the option does not exist. + */ +const char * +config_find_option_name(const config_mgr_t *mgr, const char *key) +{ + key = config_expand_abbrev(mgr, key, 0, 0); + const managed_var_t *mv = config_mgr_find_var(mgr, key, true, NULL); + if (mv) + return mv->cvar->member.name; + else + return NULL; +} + +/** Return the number of option entries in <b>fmt</b>. */ +static int +config_count_options(const config_mgr_t *mgr) +{ + return smartlist_len(mgr->all_vars); +} + +/** + * Return true iff at least one bit from <b>flag</b> is set on <b>var</b>, + * either in <b>var</b>'s flags, or on the flags of its type. + **/ +static bool +config_var_has_flag(const config_var_t *var, uint32_t flag) +{ + uint32_t have_flags = var->flags | struct_var_get_flags(&var->member); + + return (have_flags & flag) != 0; +} + +/** + * Return true if assigning a value to <b>var</b> replaces the previous + * value. Return false if assigning a value to <b>var</b> appends + * to the previous value. + **/ +static bool +config_var_is_replaced_on_set(const config_var_t *var) +{ + return ! config_var_has_flag(var, CFLG_NOREPLACE); +} + +/** + * Return true iff <b>var</b> may be assigned by name (e.g., via the + * CLI, the configuration files, or the controller API). + **/ +bool +config_var_is_settable(const config_var_t *var) +{ + return ! config_var_has_flag(var, CFLG_NOSET); +} + +/** + * Return true iff the controller is allowed to fetch the value of + * <b>var</b>. + **/ +static bool +config_var_is_gettable(const config_var_t *var) +{ + /* Arguably, invisible or obsolete options should not be gettable. However, + * they have been gettable for a long time, and making them ungettable could + * have compatibility effects. For now, let's leave them alone. + */ + + // return ! config_var_has_flag(var, CVFLAG_OBSOLETE|CFGLAGS_INVISIBLE); + (void)var; + return true; +} + +/** + * Return true iff we need to check <b>var</b> for changes when we are + * comparing config options for changes. + * + * A false result might mean that the variable is a derived variable, and that + * comparing the variable it derives from compares this one too-- or it might + * mean that there is no data to compare. + **/ +static bool +config_var_should_list_changes(const config_var_t *var) +{ + return ! config_var_has_flag(var, CFLG_NOCMP); +} + +/** + * Return true iff we need to copy the data for <b>var</b> when we are + * copying a config option. + * + * A false option might mean that the variable is a derived variable, and that + * copying the variable it derives from copies it-- or it might mean that + * there is no data to copy. + **/ +static bool +config_var_needs_copy(const config_var_t *var) +{ + return ! config_var_has_flag(var, CFLG_NOCOPY); +} + +/** + * Return true iff variable <b>var</b> should appear on list of variable + * names given to the controller or the CLI. + * + * (Note that this option is imperfectly obeyed. The + * --list-torrc-options command looks at the "settable" flag, whereas + * "GETINFO config/defaults" and "list_deprecated_*()" do not filter + * their results. It would be good for consistency to try to converge + * these behaviors in the future.) + **/ +bool +config_var_is_listable(const config_var_t *var) +{ + return ! config_var_has_flag(var, CFLG_NOLIST); +} + +/** + * Return true iff variable <b>var</b> should be written out when we + * are writing our configuration to disk, to a controller, or via the + * --dump-config command. + * + * This option may be set because a variable is hidden, or because it is + * derived from another variable which will already be written out. + **/ +static bool +config_var_is_dumpable(const config_var_t *var) +{ + return ! config_var_has_flag(var, CFLG_NODUMP); +} + +/* + * Functions to assign config options. + */ + +/** <b>c</b>-\>key is known to be a real key. Update <b>options</b> + * with <b>c</b>-\>value and return 0, or return -1 if bad value. + * + * Called from config_assign_line() and option_reset(). + */ +static int +config_assign_value(const config_mgr_t *mgr, void *options, + config_line_t *c, char **msg) +{ + const managed_var_t *var; + + CONFIG_CHECK(mgr, options); + + var = config_mgr_find_var(mgr, c->key, true, NULL); + tor_assert(var); + tor_assert(!strcmp(c->key, var->cvar->member.name)); + void *object = config_mgr_get_obj_mutable(mgr, options, var->object_idx); + + if (config_var_has_flag(var->cvar, CFLG_WARN_OBSOLETE)) { + log_warn(LD_GENERAL, "Skipping obsolete configuration option \"%s\".", + var->cvar->member.name); + } else if (config_var_has_flag(var->cvar, CFLG_WARN_DISABLED)) { + log_warn(LD_GENERAL, "This copy of Tor was built without support for " + "the option \"%s\". Skipping.", var->cvar->member.name); + } + + return struct_var_kvassign(object, c, msg, &var->cvar->member); +} + +/** Mark every linelist in <b>options</b> "fragile", so that fresh assignments + * to it will replace old ones. */ +static void +config_mark_lists_fragile(const config_mgr_t *mgr, void *options) +{ + tor_assert(mgr); + tor_assert(options); + + SMARTLIST_FOREACH_BEGIN(mgr->all_vars, const managed_var_t *, mv) { + void *object = config_mgr_get_obj_mutable(mgr, options, mv->object_idx); + struct_var_mark_fragile(object, &mv->cvar->member); + } SMARTLIST_FOREACH_END(mv); +} + +/** + * Log a warning that declaring that the option called <b>what</b> + * is deprecated because of the reason in <b>why</b>. + * + * (Both arguments must be non-NULL.) + **/ +void +warn_deprecated_option(const char *what, const char *why) +{ + const char *space = (why && strlen(why)) ? " " : ""; + log_warn(LD_CONFIG, "The %s option is deprecated, and will most likely " + "be removed in a future version of Tor.%s%s (If you think this is " + "a mistake, please let us know!)", + what, space, why); +} + +/** If <b>c</b> is a syntactically valid configuration line, update + * <b>options</b> with its value and return 0. Otherwise return -1 for bad + * key, -2 for bad value. + * + * If <b>clear_first</b> is set, clear the value first. Then if + * <b>use_defaults</b> is set, set the value to the default. + * + * Called from config_assign(). + */ +static int +config_assign_line(const config_mgr_t *mgr, void *options, + config_line_t *c, unsigned flags, + bitarray_t *options_seen, char **msg) +{ + const unsigned use_defaults = flags & CAL_USE_DEFAULTS; + const unsigned clear_first = flags & CAL_CLEAR_FIRST; + const unsigned warn_deprecations = flags & CAL_WARN_DEPRECATIONS; + const managed_var_t *mvar; + + CONFIG_CHECK(mgr, options); + + int var_index = -1; + mvar = config_mgr_find_var(mgr, c->key, true, &var_index); + if (!mvar) { + const config_format_t *fmt = mgr->toplevel; + if (fmt->extra) { + void *lvalue = STRUCT_VAR_P(options, fmt->extra->offset); + log_info(LD_CONFIG, + "Found unrecognized option '%s'; saving it.", c->key); + config_line_append((config_line_t**)lvalue, c->key, c->value); + return 0; + } else { + tor_asprintf(msg, + "Unknown option '%s'. Failing.", c->key); + return -1; + } + } + + const config_var_t *cvar = mvar->cvar; + tor_assert(cvar); + + /* Put keyword into canonical case. */ + if (strcmp(cvar->member.name, c->key)) { + tor_free(c->key); + c->key = tor_strdup(cvar->member.name); + } + + const char *deprecation_msg; + if (warn_deprecations && + (deprecation_msg = config_find_deprecation(mgr, cvar->member.name))) { + warn_deprecated_option(cvar->member.name, deprecation_msg); + } + + if (!strlen(c->value)) { + /* reset or clear it, then return */ + if (!clear_first) { + if (! config_var_is_replaced_on_set(cvar) && + c->command != CONFIG_LINE_CLEAR) { + /* We got an empty linelist from the torrc or command line. + As a special case, call this an error. Warn and ignore. */ + log_warn(LD_CONFIG, + "Linelist option '%s' has no value. Skipping.", c->key); + } else { /* not already cleared */ + config_reset(mgr, options, mvar, use_defaults); + } + } + return 0; + } else if (c->command == CONFIG_LINE_CLEAR && !clear_first) { + // This block is unreachable, since a CLEAR line always has an + // empty value, and so will trigger be handled by the previous + // "if (!strlen(c->value))" block. + + // LCOV_EXCL_START + tor_assert_nonfatal_unreached(); + config_reset(mgr, options, mvar, use_defaults); + // LCOV_EXCL_STOP + } + + if (options_seen && config_var_is_replaced_on_set(cvar)) { + /* We're tracking which options we've seen, and this option is not + * supposed to occur more than once. */ + tor_assert(var_index >= 0); + if (bitarray_is_set(options_seen, var_index)) { + log_warn(LD_CONFIG, "Option '%s' used more than once; all but the last " + "value will be ignored.", cvar->member.name); + } + bitarray_set(options_seen, var_index); + } + + if (config_assign_value(mgr, options, c, msg) < 0) + return -2; + return 0; +} + +/** Restore the option named <b>key</b> in options to its default value. + * Called from config_assign(). */ +STATIC void +config_reset_line(const config_mgr_t *mgr, void *options, + const char *key, int use_defaults) +{ + const managed_var_t *var; + + CONFIG_CHECK(mgr, options); + + var = config_mgr_find_var(mgr, key, true, NULL); + if (!var) + return; /* give error on next pass. */ + + config_reset(mgr, options, var, use_defaults); +} + +/** Return true iff value needs to be quoted and escaped to be used in + * a configuration file. */ +static int +config_value_needs_escape(const char *value) +{ + if (*value == '\"') + return 1; + while (*value) { + switch (*value) + { + case '\r': + case '\n': + case '#': + /* Note: quotes and backspaces need special handling when we are using + * quotes, not otherwise, so they don't trigger escaping on their + * own. */ + return 1; + default: + if (!TOR_ISPRINT(*value)) + return 1; + } + ++value; + } + return 0; +} + +/** Return newly allocated line or lines corresponding to <b>key</b> in the + * configuration <b>options</b>. If <b>escape_val</b> is true and a + * value needs to be quoted before it's put in a config file, quote and + * escape that value. Return NULL if no such key exists. */ +config_line_t * +config_get_assigned_option(const config_mgr_t *mgr, const void *options, + const char *key, int escape_val) +{ + const managed_var_t *var; + config_line_t *result; + + tor_assert(options && key); + + CONFIG_CHECK(mgr, options); + + var = config_mgr_find_var(mgr, key, true, NULL); + if (!var) { + log_warn(LD_CONFIG, "Unknown option '%s'. Failing.", key); + return NULL; + } + if (! config_var_is_gettable(var->cvar)) { + log_warn(LD_CONFIG, "Option '%s' is obsolete or unfetchable. Failing.", + key); + return NULL; + } + const void *object = config_mgr_get_obj(mgr, options, var->object_idx); + + result = struct_var_kvencode(object, &var->cvar->member); + + if (escape_val) { + config_line_t *line; + for (line = result; line; line = line->next) { + if (line->value && config_value_needs_escape(line->value)) { + char *newval = esc_for_log(line->value); + tor_free(line->value); + line->value = newval; + } + } + } + + return result; +} +/** Iterate through the linked list of requested options <b>list</b>. + * For each item, convert as appropriate and assign to <b>options</b>. + * If an item is unrecognized, set *msg and return -1 immediately, + * else return 0 for success. + * + * If <b>clear_first</b>, interpret config options as replacing (not + * extending) their previous values. If <b>clear_first</b> is set, + * then <b>use_defaults</b> to decide if you set to defaults after + * clearing, or make the value 0 or NULL. + * + * Here are the use cases: + * 1. A non-empty AllowInvalid line in your torrc. Appends to current + * if linelist, replaces current if csv. + * 2. An empty AllowInvalid line in your torrc. Should clear it. + * 3. "RESETCONF AllowInvalid" sets it to default. + * 4. "SETCONF AllowInvalid" makes it NULL. + * 5. "SETCONF AllowInvalid=foo" clears it and sets it to "foo". + * + * Use_defaults Clear_first + * 0 0 "append" + * 1 0 undefined, don't use + * 0 1 "set to null first" + * 1 1 "set to defaults first" + * Return 0 on success, -1 on bad key, -2 on bad value. + * + * As an additional special case, if a LINELIST config option has + * no value and clear_first is 0, then warn and ignore it. + */ + +/* +There are three call cases for config_assign() currently. + +Case one: Torrc entry +options_init_from_torrc() calls config_assign(0, 0) + calls config_assign_line(0, 0). + if value is empty, calls config_reset(0) and returns. + calls config_assign_value(), appends. + +Case two: setconf +options_trial_assign() calls config_assign(0, 1) + calls config_reset_line(0) + calls config_reset(0) + calls option_clear(). + calls config_assign_line(0, 1). + if value is empty, returns. + calls config_assign_value(), appends. + +Case three: resetconf +options_trial_assign() calls config_assign(1, 1) + calls config_reset_line(1) + calls config_reset(1) + calls option_clear(). + calls config_assign_value(default) + calls config_assign_line(1, 1). + returns. +*/ +int +config_assign(const config_mgr_t *mgr, void *options, config_line_t *list, + unsigned config_assign_flags, char **msg) +{ + config_line_t *p; + bitarray_t *options_seen; + const int n_options = config_count_options(mgr); + const unsigned clear_first = config_assign_flags & CAL_CLEAR_FIRST; + const unsigned use_defaults = config_assign_flags & CAL_USE_DEFAULTS; + + CONFIG_CHECK(mgr, options); + + /* pass 1: normalize keys */ + for (p = list; p; p = p->next) { + const char *full = config_expand_abbrev(mgr, p->key, 0, 1); + if (strcmp(full,p->key)) { + tor_free(p->key); + p->key = tor_strdup(full); + } + } + + /* pass 2: if we're reading from a resetting source, clear all + * mentioned config options, and maybe set to their defaults. */ + if (clear_first) { + for (p = list; p; p = p->next) + config_reset_line(mgr, options, p->key, use_defaults); + } + + options_seen = bitarray_init_zero(n_options); + /* pass 3: assign. */ + while (list) { + int r; + if ((r=config_assign_line(mgr, options, list, config_assign_flags, + options_seen, msg))) { + bitarray_free(options_seen); + return r; + } + list = list->next; + } + bitarray_free(options_seen); + + /** Now we're done assigning a group of options to the configuration. + * Subsequent group assignments should _replace_ linelists, not extend + * them. */ + config_mark_lists_fragile(mgr, options); + + return 0; +} + +/** Reset config option <b>var</b> to 0, 0.0, NULL, or the equivalent. + * Called from config_reset() and config_free(). */ +static void +config_clear(const config_mgr_t *mgr, void *options, const managed_var_t *var) +{ + void *object = config_mgr_get_obj_mutable(mgr, options, var->object_idx); + struct_var_free(object, &var->cvar->member); +} + +/** Clear the option indexed by <b>var</b> in <b>options</b>. Then if + * <b>use_defaults</b>, set it to its default value. + * Called by config_init() and option_reset_line() and option_assign_line(). */ +static void +config_reset(const config_mgr_t *mgr, void *options, + const managed_var_t *var, int use_defaults) +{ + config_line_t *c; + char *msg = NULL; + CONFIG_CHECK(mgr, options); + config_clear(mgr, options, var); /* clear it first */ + + if (!use_defaults) + return; /* all done */ + + if (var->cvar->initvalue) { + c = tor_malloc_zero(sizeof(config_line_t)); + c->key = tor_strdup(var->cvar->member.name); + c->value = tor_strdup(var->cvar->initvalue); + if (config_assign_value(mgr, options, c, &msg) < 0) { + // LCOV_EXCL_START + log_warn(LD_BUG, "Failed to assign default: %s", msg); + tor_free(msg); /* if this happens it's a bug */ + // LCOV_EXCL_STOP + } + config_free_lines(c); + } +} + +/** Release storage held by <b>options</b>. */ +void +config_free_(const config_mgr_t *mgr, void *options) +{ + if (!options) + return; + + tor_assert(mgr); + + if (mgr->toplevel->clear_fn) { + mgr->toplevel->clear_fn(mgr, options); + } + config_suite_t **suitep = config_mgr_get_suite_ptr(mgr, options); + if (suitep) { + tor_assert(smartlist_len((*suitep)->configs) == + smartlist_len(mgr->subconfigs)); + SMARTLIST_FOREACH_BEGIN(mgr->subconfigs, const config_format_t *, fmt) { + void *obj = smartlist_get((*suitep)->configs, fmt_sl_idx); + if (fmt->clear_fn) { + fmt->clear_fn(mgr, obj); + } + } SMARTLIST_FOREACH_END(fmt); + } + + SMARTLIST_FOREACH_BEGIN(mgr->all_vars, const managed_var_t *, mv) { + config_clear(mgr, options, mv); + } SMARTLIST_FOREACH_END(mv); + + if (mgr->toplevel->extra) { + config_line_t **linep = STRUCT_VAR_P(options, + mgr->toplevel->extra->offset); + config_free_lines(*linep); + *linep = NULL; + } + + if (suitep) { + SMARTLIST_FOREACH((*suitep)->configs, void *, obj, tor_free(obj)); + config_suite_free(*suitep); + } + + tor_free(options); +} + +/** Return true iff the option <b>name</b> has the same value in <b>o1</b> + * and <b>o2</b>. Must not be called for LINELIST_S or OBSOLETE options. + */ +int +config_is_same(const config_mgr_t *mgr, + const void *o1, const void *o2, + const char *name) +{ + CONFIG_CHECK(mgr, o1); + CONFIG_CHECK(mgr, o2); + + const managed_var_t *var = config_mgr_find_var(mgr, name, true, NULL); + if (!var) { + return true; + } + const void *obj1 = config_mgr_get_obj(mgr, o1, var->object_idx); + const void *obj2 = config_mgr_get_obj(mgr, o2, var->object_idx); + + return struct_var_eq(obj1, obj2, &var->cvar->member); +} + +/** + * Return a list of the options which have changed between <b>options1</b> and + * <b>options2</b>. If an option has reverted to its default value, it has a + * value entry of NULL. + * + * <b>options1</b> and <b>options2</b> must be top-level configuration objects + * of the type managed by <b>mgr</b>. + **/ +config_line_t * +config_get_changes(const config_mgr_t *mgr, + const void *options1, const void *options2) +{ + config_line_t *result = NULL; + config_line_t **next = &result; + SMARTLIST_FOREACH_BEGIN(mgr->all_vars, managed_var_t *, mv) { + if (! config_var_should_list_changes(mv->cvar)) { + /* something else will check this var, or it doesn't need checking */ + continue; + } + const void *obj1 = config_mgr_get_obj(mgr, options1, mv->object_idx); + const void *obj2 = config_mgr_get_obj(mgr, options2, mv->object_idx); + + if (struct_var_eq(obj1, obj2, &mv->cvar->member)) { + continue; + } + + const char *varname = mv->cvar->member.name; + config_line_t *line = + config_get_assigned_option(mgr, options2, varname, 1); + + if (line) { + *next = line; + } else { + *next = tor_malloc_zero(sizeof(config_line_t)); + (*next)->key = tor_strdup(varname); + } + while (*next) + next = &(*next)->next; + } SMARTLIST_FOREACH_END(mv); + + return result; +} + +/** Copy storage held by <b>old</b> into a new or_options_t and return it. */ +void * +config_dup(const config_mgr_t *mgr, const void *old) +{ + void *newopts; + + newopts = config_new(mgr); + SMARTLIST_FOREACH_BEGIN(mgr->all_vars, managed_var_t *, mv) { + if (! config_var_needs_copy(mv->cvar)) { + // Something else will copy this option, or it doesn't need copying. + continue; + } + const void *oldobj = config_mgr_get_obj(mgr, old, mv->object_idx); + void *newobj = config_mgr_get_obj_mutable(mgr, newopts, mv->object_idx); + if (struct_var_copy(newobj, oldobj, &mv->cvar->member) < 0) { + // LCOV_EXCL_START + log_err(LD_BUG, "Unable to copy value for %s.", + mv->cvar->member.name); + tor_assert_unreached(); + // LCOV_EXCL_STOP + } + } SMARTLIST_FOREACH_END(mv); + + return newopts; +} +/** Set all vars in the configuration object <b>options</b> to their default + * values. */ +void +config_init(const config_mgr_t *mgr, void *options) +{ + CONFIG_CHECK(mgr, options); + + SMARTLIST_FOREACH_BEGIN(mgr->all_vars, const managed_var_t *, mv) { + if (!mv->cvar->initvalue) + continue; /* defaults to NULL or 0 */ + config_reset(mgr, options, mv, 1); + } SMARTLIST_FOREACH_END(mv); +} + +/** + * Helper for config_validate_single: see whether any immutable option + * has changed between old_options and new_options. + * + * On success return 0; on failure set *msg_out to a newly allocated + * string explaining what is wrong, and return -1. + */ +static int +config_check_immutable_flags(const config_format_t *fmt, + const void *old_options, + const void *new_options, + char **msg_out) +{ + tor_assert(fmt); + tor_assert(new_options); + if (BUG(! old_options)) + return 0; + + unsigned i; + for (i = 0; fmt->vars[i].member.name; ++i) { + const config_var_t *v = &fmt->vars[i]; + if (! config_var_has_flag(v, CFLG_IMMUTABLE)) + continue; + + if (! struct_var_eq(old_options, new_options, &v->member)) { + tor_asprintf(msg_out, + "While Tor is running, changing %s is not allowed", + v->member.name); + return -1; + } + } + + return 0; +} + +/** + * Normalize and validate a single object `options` within a configuration + * suite, according to its format. `options` may be modified as appropriate + * in order to set ancillary data. If `old_options` is provided, make sure + * that the transition from `old_options` to `options` is permitted. + * + * On success return VSTAT_OK; on failure set *msg_out to a newly allocated + * string explaining what is wrong, and return a different validation_status_t + * to describe which step failed. + **/ +static validation_status_t +config_validate_single(const config_format_t *fmt, + const void *old_options, void *options, + char **msg_out) +{ + tor_assert(fmt); + tor_assert(options); + + if (fmt->pre_normalize_fn) { + if (fmt->pre_normalize_fn(options, msg_out) < 0) { + return VSTAT_PRE_NORMALIZE_ERR; + } + } + + if (fmt->legacy_validate_fn) { + if (fmt->legacy_validate_fn(old_options, options, msg_out) < 0) { + return VSTAT_LEGACY_ERR; + } + } + + if (fmt->validate_fn) { + if (fmt->validate_fn(options, msg_out) < 0) { + return VSTAT_VALIDATE_ERR; + } + } + + if (old_options) { + if (config_check_immutable_flags(fmt, old_options, options, msg_out) < 0) { + return VSTAT_TRANSITION_ERR; + } + + if (fmt->check_transition_fn) { + if (fmt->check_transition_fn(old_options, options, msg_out) < 0) { + return VSTAT_TRANSITION_ERR; + } + } + } + + if (fmt->post_normalize_fn) { + if (fmt->post_normalize_fn(options, msg_out) < 0) { + return VSTAT_POST_NORMALIZE_ERR; + } + } + + return VSTAT_OK; +} + +/** + * Normalize and validate all the options in configuration object `options` + * and its sub-objects. `options` may be modified as appropriate in order to + * set ancillary data. If `old_options` is provided, make sure that the + * transition from `old_options` to `options` is permitted. + * + * On success return VSTAT_OK; on failure set *msg_out to a newly allocated + * string explaining what is wrong, and return a different validation_status_t + * to describe which step failed. + **/ +validation_status_t +config_validate(const config_mgr_t *mgr, + const void *old_options, void *options, + char **msg_out) +{ + validation_status_t rv; + CONFIG_CHECK(mgr, options); + if (old_options) { + CONFIG_CHECK(mgr, old_options); + } + + config_suite_t **suitep_new = config_mgr_get_suite_ptr(mgr, options); + config_suite_t **suitep_old = NULL; + if (old_options) + suitep_old = config_mgr_get_suite_ptr(mgr, (void*) old_options); + + /* Validate the sub-objects */ + if (suitep_new) { + SMARTLIST_FOREACH_BEGIN(mgr->subconfigs, const config_format_t *, fmt) { + void *obj = smartlist_get((*suitep_new)->configs, fmt_sl_idx); + const void *obj_old=NULL; + if (suitep_old) + obj_old = smartlist_get((*suitep_old)->configs, fmt_sl_idx); + + rv = config_validate_single(fmt, obj_old, obj, msg_out); + if (rv < 0) + return rv; + } SMARTLIST_FOREACH_END(fmt); + } + + /* Validate the top-level object. */ + rv = config_validate_single(mgr->toplevel, old_options, options, msg_out); + if (rv < 0) + return rv; + + return VSTAT_OK; +} + +/** Allocate and return a new string holding the written-out values of the vars + * in 'options'. If 'minimal', do not write out any default-valued vars. + * Else, if comment_defaults, write default values as comments. + */ +char * +config_dump(const config_mgr_t *mgr, const void *default_options, + const void *options, int minimal, + int comment_defaults) +{ + const config_format_t *fmt = mgr->toplevel; + smartlist_t *elements; + const void *defaults = default_options; + void *defaults_tmp = NULL; + config_line_t *line, *assigned; + char *result; + char *msg = NULL; + + if (defaults == NULL) { + defaults = defaults_tmp = config_new(mgr); + config_init(mgr, defaults_tmp); + } + + /* XXX use a 1 here so we don't add a new log line while dumping */ + if (default_options == NULL) { + if (config_validate(mgr, NULL, defaults_tmp, &msg) < 0) { + // LCOV_EXCL_START + log_err(LD_BUG, "Failed to validate default config: %s", msg); + tor_free(msg); + tor_assert(0); + // LCOV_EXCL_STOP + } + } + + elements = smartlist_new(); + SMARTLIST_FOREACH_BEGIN(mgr->all_vars, managed_var_t *, mv) { + int comment_option = 0; + /* Don't save 'hidden' control variables. */ + if (! config_var_is_dumpable(mv->cvar)) + continue; + const char *name = mv->cvar->member.name; + if (minimal && config_is_same(mgr, options, defaults, name)) + continue; + else if (comment_defaults && + config_is_same(mgr, options, defaults, name)) + comment_option = 1; + + line = assigned = + config_get_assigned_option(mgr, options, name, 1); + + for (; line; line = line->next) { + if (!strcmpstart(line->key, "__")) { + /* This check detects "hidden" variables inside LINELIST_V structures. + */ + continue; + } + int value_exists = line->value && *(line->value); + smartlist_add_asprintf(elements, "%s%s%s%s\n", + comment_option ? "# " : "", + line->key, value_exists ? " " : "", line->value); + } + config_free_lines(assigned); + } SMARTLIST_FOREACH_END(mv); + + if (fmt->extra) { + line = *(config_line_t**)STRUCT_VAR_P(options, fmt->extra->offset); + for (; line; line = line->next) { + int value_exists = line->value && *(line->value); + smartlist_add_asprintf(elements, "%s%s%s\n", + line->key, value_exists ? " " : "", line->value); + } + } + + result = smartlist_join_strings(elements, "", 0, NULL); + SMARTLIST_FOREACH(elements, char *, cp, tor_free(cp)); + smartlist_free(elements); + config_free(mgr, defaults_tmp); + return result; +} + +/** + * Return true if every member of <b>options</b> is in-range and well-formed. + * Return false otherwise. Log errors at level <b>severity</b>. + */ +bool +config_check_ok(const config_mgr_t *mgr, const void *options, int severity) +{ + bool all_ok = true; + + SMARTLIST_FOREACH_BEGIN(mgr->all_vars, const managed_var_t *, mv) { + if (!struct_var_ok(options, &mv->cvar->member)) { + log_fn(severity, LD_BUG, "Invalid value for %s", + mv->cvar->member.name); + all_ok = false; + } + } SMARTLIST_FOREACH_END(mv); + + return all_ok; +} diff --git a/src/lib/confmgt/confmgt.h b/src/lib/confmgt/confmgt.h new file mode 100644 index 0000000000..5065c13b60 --- /dev/null +++ b/src/lib/confmgt/confmgt.h @@ -0,0 +1,136 @@ +/* Copyright (c) 2001 Matej Pfajfar. + * Copyright (c) 2001-2004, Roger Dingledine. + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2020, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * \file confmgt.h + * + * \brief Header for confmgt.c. + */ + +#ifndef TOR_CONFMGT_H +#define TOR_CONFMGT_H + +#include "lib/conf/conftypes.h" +#include "lib/conf/confmacros.h" +#include "lib/testsupport/testsupport.h" + +/** + * A collection of config_format_t objects to describe several objects + * that are all configured with the same configuration file. + * + * (NOTE: for now, this only handles a single config_format_t.) + **/ +typedef struct config_mgr_t config_mgr_t; + +config_mgr_t *config_mgr_new(const config_format_t *toplevel_fmt); +void config_mgr_free_(config_mgr_t *mgr); +int config_mgr_add_format(config_mgr_t *mgr, + const config_format_t *fmt); +void config_mgr_freeze(config_mgr_t *mgr); +#define config_mgr_free(mgr) \ + FREE_AND_NULL(config_mgr_t, config_mgr_free_, (mgr)) +struct smartlist_t *config_mgr_list_vars(const config_mgr_t *mgr); +struct smartlist_t *config_mgr_list_deprecated_vars(const config_mgr_t *mgr); + +/** A collection of managed configuration objects. */ +typedef struct config_suite_t config_suite_t; + +/** + * Flag for config_assign: if set, then "resetting" an option changes it to + * its default value, as specified in the config_var_t. Otherwise, + * "resetting" an option changes it to a type-dependent null value -- + * typically 0 or NULL. + * + * (An option is "reset" when it is set to an empty value, or as described in + * CAL_CLEAR_FIRST). + **/ +#define CAL_USE_DEFAULTS (1u<<0) +/** + * Flag for config_assign: if set, then we reset every provided config + * option before we set it. + * + * For example, if this flag is not set, then passing a multi-line option to + * config_assign will cause any previous value to be extended. But if this + * flag is set, then a multi-line option will replace any previous value. + **/ +#define CAL_CLEAR_FIRST (1u<<1) +/** + * Flag for config_assign: if set, we warn about deprecated options. + **/ +#define CAL_WARN_DEPRECATIONS (1u<<2) + +void *config_new(const config_mgr_t *fmt); +void config_free_(const config_mgr_t *fmt, void *options); +#define config_free(mgr, options) do { \ + config_free_((mgr), (options)); \ + (options) = NULL; \ + } while (0) + +struct config_line_t *config_get_assigned_option(const config_mgr_t *mgr, + const void *options, const char *key, + int escape_val); +int config_is_same(const config_mgr_t *fmt, + const void *o1, const void *o2, + const char *name); +struct config_line_t *config_get_changes(const config_mgr_t *mgr, + const void *options1, const void *options2); +void config_init(const config_mgr_t *mgr, void *options); + +/** An enumeration to report which validation step failed. */ +typedef enum { + VSTAT_PRE_NORMALIZE_ERR = -5, + VSTAT_VALIDATE_ERR = -4, + VSTAT_LEGACY_ERR = -3, + VSTAT_TRANSITION_ERR = -2, + VSTAT_POST_NORMALIZE_ERR = -1, + VSTAT_OK = 0, +} validation_status_t; + +validation_status_t config_validate(const config_mgr_t *mgr, + const void *old_options, void *options, + char **msg_out); +void *config_dup(const config_mgr_t *mgr, const void *old); +char *config_dump(const config_mgr_t *mgr, const void *default_options, + const void *options, int minimal, + int comment_defaults); +void config_check_toplevel_magic(const config_mgr_t *mgr, + const void *object); +bool config_check_ok(const config_mgr_t *mgr, const void *options, + int severity); +int config_assign(const config_mgr_t *mgr, void *options, + struct config_line_t *list, + unsigned flags, char **msg); +const char *config_find_deprecation(const config_mgr_t *mgr, + const char *key); +const char *config_find_option_name(const config_mgr_t *mgr, + const char *key); +const char *config_expand_abbrev(const config_mgr_t *mgr, + const char *option, + int command_line, int warn_obsolete); +void warn_deprecated_option(const char *what, const char *why); + +bool config_var_is_settable(const config_var_t *var); +bool config_var_is_listable(const config_var_t *var); + +/* Helper macros to compare an option across two configuration objects */ +#define CFG_EQ_BOOL(a,b,opt) ((a)->opt == (b)->opt) +#define CFG_EQ_INT(a,b,opt) ((a)->opt == (b)->opt) +#define CFG_EQ_STRING(a,b,opt) (!strcmp_opt((a)->opt, (b)->opt)) +#define CFG_EQ_SMARTLIST(a,b,opt) smartlist_strings_eq((a)->opt, (b)->opt) +#define CFG_EQ_LINELIST(a,b,opt) config_lines_eq((a)->opt, (b)->opt) +#define CFG_EQ_ROUTERSET(a,b,opt) routerset_equal((a)->opt, (b)->opt) + +void *config_mgr_get_obj_mutable(const config_mgr_t *mgr, + void *toplevel, int idx); +const void *config_mgr_get_obj(const config_mgr_t *mgr, + const void *toplevel, int idx); + +#ifdef CONFMGT_PRIVATE +STATIC void config_reset_line(const config_mgr_t *mgr, void *options, + const char *key, int use_defaults); +#endif /* defined(CONFMGT_PRIVATE) */ + +#endif /* !defined(TOR_CONFMGT_H) */ diff --git a/src/lib/confmgt/include.am b/src/lib/confmgt/include.am new file mode 100644 index 0000000000..d3a7a7cd69 --- /dev/null +++ b/src/lib/confmgt/include.am @@ -0,0 +1,27 @@ +noinst_LIBRARIES += src/lib/libtor-confmgt.a + +if UNITTESTS_ENABLED +noinst_LIBRARIES += src/lib/libtor-confmgt-testing.a +endif + +# ADD_C_FILE: INSERT SOURCES HERE. +src_lib_libtor_confmgt_a_SOURCES = \ + src/lib/confmgt/confmgt.c \ + src/lib/confmgt/structvar.c \ + src/lib/confmgt/type_defs.c \ + src/lib/confmgt/typedvar.c \ + src/lib/confmgt/unitparse.c + +src_lib_libtor_confmgt_testing_a_SOURCES = \ + $(src_lib_libtor_confmgt_a_SOURCES) +src_lib_libtor_confmgt_testing_a_CPPFLAGS = $(AM_CPPFLAGS) $(TEST_CPPFLAGS) +src_lib_libtor_confmgt_testing_a_CFLAGS = $(AM_CFLAGS) $(TEST_CFLAGS) + +# ADD_C_FILE: INSERT HEADERS HERE. +noinst_HEADERS += \ + src/lib/confmgt/confmgt.h \ + src/lib/confmgt/structvar.h \ + src/lib/confmgt/type_defs.h \ + src/lib/confmgt/typedvar.h \ + src/lib/confmgt/unitparse.h \ + src/lib/confmgt/var_type_def_st.h diff --git a/src/lib/confmgt/lib_confmgt.md b/src/lib/confmgt/lib_confmgt.md new file mode 100644 index 0000000000..861e720f64 --- /dev/null +++ b/src/lib/confmgt/lib_confmgt.md @@ -0,0 +1,7 @@ +@dir /lib/confmgt +@brief lib/confmgt: Parse, encode, manipulate configuration files. + +This logic is used in common by our state files (statefile.c) and +configuration files (config.c) to manage a set of named, typed fields, +reading and writing them to disk and to the controller. + diff --git a/src/lib/confmgt/structvar.c b/src/lib/confmgt/structvar.c new file mode 100644 index 0000000000..55deb4759c --- /dev/null +++ b/src/lib/confmgt/structvar.c @@ -0,0 +1,239 @@ +/* Copyright (c) 2001 Matej Pfajfar. + * Copyright (c) 2001-2004, Roger Dingledine. + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2020, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * @file structvar.c + * @brief Functions to manipulate named and typed elements of + * a structure. + * + * These functions represent a low-level API for accessing a member of a + * structure. They use typedvar.c to work, and they are used in turn by the + * configuration system to examine and set fields in configuration objects + * used by individual modules. + * + * Almost no code should call these directly. + **/ + +#include "orconfig.h" +#include "lib/confmgt/structvar.h" +#include "lib/cc/compat_compiler.h" +#include "lib/conf/conftypes.h" +#include "lib/confmgt/type_defs.h" +#include "lib/confmgt/typedvar.h" +#include "lib/log/util_bug.h" + +#include "lib/confmgt/var_type_def_st.h" + +#include <stddef.h> + +/** + * Return true iff all fields on <b>decl</b> are NULL or 0, indicating that + * there is no object or no magic number to check. + **/ +static inline bool +magic_is_null(const struct_magic_decl_t *decl) +{ + return decl->typename == NULL && + decl->magic_offset == 0 && + decl->magic_val == 0; +} + +/** + * Set the 'magic number' on <b>object</b> to correspond to decl. + **/ +void +struct_set_magic(void *object, const struct_magic_decl_t *decl) +{ + tor_assert(decl); + if (magic_is_null(decl)) + return; + + tor_assert(object); + uint32_t *ptr = STRUCT_VAR_P(object, decl->magic_offset); + *ptr = decl->magic_val; +} + +/** + * Assert that the 'magic number' on <b>object</b> to corresponds to decl. + **/ +void +struct_check_magic(const void *object, const struct_magic_decl_t *decl) +{ + tor_assert(decl); + if (magic_is_null(decl)) + return; + + tor_assert(object); + + const uint32_t *ptr = STRUCT_VAR_P(object, decl->magic_offset); + tor_assertf(*ptr == decl->magic_val, + "Bad magic number on purported %s object. " + "Expected %"PRIu32"x but got %"PRIu32"x.", + decl->typename, decl->magic_val, *ptr); +} + +/** + * Return a mutable pointer to the member of <b>object</b> described + * by <b>member</b>. + **/ +void * +struct_get_mptr(void *object, const struct_member_t *member) +{ + tor_assert(object); + return STRUCT_VAR_P(object, member->offset); +} + +/** + * Return a const pointer to the member of <b>object</b> described + * by <b>member</b>. + **/ +const void * +struct_get_ptr(const void *object, const struct_member_t *member) +{ + tor_assert(object); + return STRUCT_VAR_P(object, member->offset); +} + +/** + * Helper: given a struct_member_t, look up the type definition for its + * variable. + */ +static const var_type_def_t * +get_type_def(const struct_member_t *member) +{ + if (member->type_def) + return member->type_def; + + return lookup_type_def(member->type); +} + +/** + * (As typed_var_free, but free and clear the member of <b>object</b> defined + * by <b>member</b>.) + **/ +void +struct_var_free(void *object, const struct_member_t *member) +{ + void *p = struct_get_mptr(object, member); + const var_type_def_t *def = get_type_def(member); + + typed_var_free(p, def); +} + +/** + * (As typed_var_copy, but copy from <b>src</b> to <b>dest</b> the member + * defined by <b>member</b>.) + **/ +int +struct_var_copy(void *dest, const void *src, const struct_member_t *member) +{ + void *p_dest = struct_get_mptr(dest, member); + const void *p_src = struct_get_ptr(src, member); + const var_type_def_t *def = get_type_def(member); + + return typed_var_copy(p_dest, p_src, def); +} + +/** + * (As typed_var_eq, but compare the members of <b>a</b> and <b>b</b> + * defined by <b>member</b>.) + **/ +bool +struct_var_eq(const void *a, const void *b, const struct_member_t *member) +{ + const void *p_a = struct_get_ptr(a, member); + const void *p_b = struct_get_ptr(b, member); + const var_type_def_t *def = get_type_def(member); + + return typed_var_eq(p_a, p_b, def); +} + +/** + * (As typed_var_ok, but validate the member of <b>object</b> defined by + * <b>member</b>.) + **/ +bool +struct_var_ok(const void *object, const struct_member_t *member) +{ + const void *p = struct_get_ptr(object, member); + const var_type_def_t *def = get_type_def(member); + + return typed_var_ok(p, def); +} + +/** + * (As typed_var_kvassign, but assign a value to the member of <b>object</b> + * defined by <b>member</b>.) + **/ +int +struct_var_kvassign(void *object, const struct config_line_t *line, + char **errmsg, + const struct_member_t *member) +{ + void *p = struct_get_mptr(object, member); + const var_type_def_t *def = get_type_def(member); + + return typed_var_kvassign(p, line, errmsg, def); +} + +/** + * (As typed_var_kvencode, but encode the value of the member of <b>object</b> + * defined by <b>member</b>.) + **/ +struct config_line_t * +struct_var_kvencode(const void *object, const struct_member_t *member) +{ + const void *p = struct_get_ptr(object, member); + const var_type_def_t *def = get_type_def(member); + + return typed_var_kvencode(member->name, p, def); +} + +/** + * Mark the field in <b>object</b> determined by <b>member</b> -- a variable + * that ordinarily would be extended by assignment -- as "fragile", so that it + * will get replaced by the next assignment instead. + */ +void +struct_var_mark_fragile(void *object, const struct_member_t *member) +{ + void *p = struct_get_mptr(object, member); + const var_type_def_t *def = get_type_def(member); + return typed_var_mark_fragile(p, def); +} + +/** + * Return the official name of this struct member. + **/ +const char * +struct_var_get_name(const struct_member_t *member) +{ + return member->name; +} + +/** + * Return the type name for this struct member. + * + * Do not use the output of this function to inspect a type within Tor. It is + * suitable for debugging, informing the controller or user of a variable's + * type, etc. + **/ +const char * +struct_var_get_typename(const struct_member_t *member) +{ + const var_type_def_t *def = get_type_def(member); + + return def ? def->name : NULL; +} + +/** Return all of the flags set for this struct member. */ +uint32_t +struct_var_get_flags(const struct_member_t *member) +{ + const var_type_def_t *def = get_type_def(member); + + return def ? def->flags : 0; +} diff --git a/src/lib/confmgt/structvar.h b/src/lib/confmgt/structvar.h new file mode 100644 index 0000000000..91334fa8c5 --- /dev/null +++ b/src/lib/confmgt/structvar.h @@ -0,0 +1,54 @@ +/* Copyright (c) 2001 Matej Pfajfar. + * Copyright (c) 2001-2004, Roger Dingledine. + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2020, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * @file structvar.h + * @brief Header for lib/confmgt/structvar.c + **/ + +#ifndef TOR_LIB_CONFMGT_STRUCTVAR_H +#define TOR_LIB_CONFMGT_STRUCTVAR_H + +struct struct_magic_decl_t; +struct struct_member_t; +struct config_line_t; + +#include <stdbool.h> +#include "lib/cc/torint.h" + +void struct_set_magic(void *object, + const struct struct_magic_decl_t *decl); +void struct_check_magic(const void *object, + const struct struct_magic_decl_t *decl); + +void *struct_get_mptr(void *object, + const struct struct_member_t *member); +const void *struct_get_ptr(const void *object, + const struct struct_member_t *member); + +void struct_var_free(void *object, + const struct struct_member_t *member); +int struct_var_copy(void *dest, const void *src, + const struct struct_member_t *member); +bool struct_var_eq(const void *a, const void *b, + const struct struct_member_t *member); +bool struct_var_ok(const void *object, + const struct struct_member_t *member); +void struct_var_mark_fragile(void *object, + const struct struct_member_t *member); + +const char *struct_var_get_name(const struct struct_member_t *member); +const char *struct_var_get_typename(const struct struct_member_t *member); +uint32_t struct_var_get_flags(const struct struct_member_t *member); + +int struct_var_kvassign(void *object, const struct config_line_t *line, + char **errmsg, + const struct struct_member_t *member); +struct config_line_t *struct_var_kvencode( + const void *object, + const struct struct_member_t *member); + +#endif /* !defined(TOR_LIB_CONFMGT_STRUCTVAR_H) */ diff --git a/src/lib/confmgt/type_defs.c b/src/lib/confmgt/type_defs.c new file mode 100644 index 0000000000..d9e5e1e4c2 --- /dev/null +++ b/src/lib/confmgt/type_defs.c @@ -0,0 +1,849 @@ +/* Copyright (c) 2001 Matej Pfajfar. + * Copyright (c) 2001-2004, Roger Dingledine. + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2020, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * @file type_defs.c + * @brief Definitions for various low-level configuration types. + * + * This module creates a number of var_type_def_t objects, to be used by + * typedvar.c in manipulating variables. + * + * The types here are common types that can be implemented with Tor's + * low-level functionality. To define new types, see var_type_def_st.h. + **/ + +#include "orconfig.h" +#include "lib/conf/conftypes.h" +#include "lib/conf/confdecl.h" +#include "lib/confmgt/typedvar.h" +#include "lib/confmgt/type_defs.h" +#include "lib/confmgt/unitparse.h" + +#include "lib/cc/compat_compiler.h" +#include "lib/container/smartlist.h" +#include "lib/encoding/confline.h" +#include "lib/encoding/time_fmt.h" +#include "lib/log/escape.h" +#include "lib/log/log.h" +#include "lib/log/util_bug.h" +#include "lib/malloc/malloc.h" +#include "lib/string/parse_int.h" +#include "lib/string/printf.h" + +#include "lib/confmgt/var_type_def_st.h" + +#include <stddef.h> +#include <string.h> +#include <errno.h> + +////// +// CONFIG_TYPE_STRING +// CONFIG_TYPE_FILENAME +// +// These two types are the same for now, but they have different names. +// +// Warning: For this type, the default value (NULL) and "" are considered +// different values. That is generally risky, and best avoided for other +// types in the future. +////// + +static int +string_parse(void *target, const char *value, char **errmsg, + const void *params) +{ + (void)params; + (void)errmsg; + char **p = (char**)target; + *p = tor_strdup(value); + return 0; +} + +static char * +string_encode(const void *value, const void *params) +{ + (void)params; + const char **p = (const char**)value; + return *p ? tor_strdup(*p) : NULL; +} + +static void +string_clear(void *value, const void *params) +{ + (void)params; + char **p = (char**)value; + tor_free(*p); // sets *p to NULL. +} + +static const var_type_fns_t string_fns = { + .parse = string_parse, + .encode = string_encode, + .clear = string_clear, +}; + +///// +// CONFIG_TYPE_INT +// CONFIG_TYPE_POSINT +// +// These types are implemented as int, possibly with a restricted range. +///// + +/** + * Parameters for parsing an integer type. + **/ +typedef struct int_type_params_t { + int minval; /**< Lowest allowed value */ + int maxval; /**< Highest allowed value */ +} int_parse_params_t; + +static const int_parse_params_t INT_PARSE_UNRESTRICTED = { + .minval = INT_MIN, + .maxval = INT_MAX, +}; + +static const int_parse_params_t INT_PARSE_POSINT = { + .minval = 0, + .maxval = INT_MAX, +}; + +static int +int_parse(void *target, const char *value, char **errmsg, const void *params) +{ + const int_parse_params_t *pp; + if (params) { + pp = params; + } else { + pp = &INT_PARSE_UNRESTRICTED; + } + int *p = target; + int ok=0; + *p = (int)tor_parse_long(value, 10, pp->minval, pp->maxval, &ok, NULL); + if (!ok) { + tor_asprintf(errmsg, "Integer %s is malformed or out of bounds. " + "Allowed values are between %d and %d.", + value, pp->minval, pp->maxval); + return -1; + } + return 0; +} + +static char * +int_encode(const void *value, const void *params) +{ + (void)params; + int v = *(int*)value; + char *result; + tor_asprintf(&result, "%d", v); + return result; +} + +static void +int_clear(void *value, const void *params) +{ + (void)params; + *(int*)value = 0; +} + +static bool +int_ok(const void *value, const void *params) +{ + const int_parse_params_t *pp = params; + if (pp) { + int v = *(int*)value; + return pp->minval <= v && v <= pp->maxval; + } else { + return true; + } +} + +static const var_type_fns_t int_fns = { + .parse = int_parse, + .encode = int_encode, + .clear = int_clear, + .ok = int_ok, +}; + +///// +// CONFIG_TYPE_UINT64 +// +// This type is an unrestricted u64. +///// + +static int +uint64_parse(void *target, const char *value, char **errmsg, + const void *params) +{ + (void)params; + (void)errmsg; + uint64_t *p = target; + int ok=0; + *p = tor_parse_uint64(value, 10, 0, UINT64_MAX, &ok, NULL); + if (!ok) { + tor_asprintf(errmsg, "Integer %s is malformed or out of bounds.", + value); + return -1; + } + return 0; +} + +static char * +uint64_encode(const void *value, const void *params) +{ + (void)params; + uint64_t v = *(uint64_t*)value; + char *result; + tor_asprintf(&result, "%"PRIu64, v); + return result; +} + +static void +uint64_clear(void *value, const void *params) +{ + (void)params; + *(uint64_t*)value = 0; +} + +static const var_type_fns_t uint64_fns = { + .parse = uint64_parse, + .encode = uint64_encode, + .clear = uint64_clear, +}; + +///// +// CONFIG_TYPE_INTERVAL +// CONFIG_TYPE_MSEC_INTERVAL +// CONFIG_TYPE_MEMUNIT +// +// These types are implemented using the config_parse_units() function. +// The intervals are stored as ints, whereas memory units are stored as +// uint64_ts. +///// + +static int +units_parse_u64(void *target, const char *value, char **errmsg, + const void *params) +{ + const unit_table_t *table = params; + tor_assert(table); + uint64_t *v = (uint64_t*)target; + int ok=1; + char *msg = NULL; + *v = config_parse_units(value, table, &ok, &msg); + if (!ok) { + tor_asprintf(errmsg, "Provided value is malformed or out of bounds: %s", + msg); + tor_free(msg); + return -1; + } + if (BUG(msg)) { + tor_free(msg); + } + return 0; +} + +static int +units_parse_int(void *target, const char *value, char **errmsg, + const void *params) +{ + const unit_table_t *table = params; + tor_assert(table); + int *v = (int*)target; + int ok=1; + char *msg = NULL; + uint64_t u64 = config_parse_units(value, table, &ok, &msg); + if (!ok) { + tor_asprintf(errmsg, "Provided value is malformed or out of bounds: %s", + msg); + tor_free(msg); + return -1; + } + if (BUG(msg)) { + tor_free(msg); + } + if (u64 > INT_MAX) { + tor_asprintf(errmsg, "Provided value %s is too large", value); + return -1; + } + *v = (int) u64; + return 0; +} + +static bool +units_ok_int(const void *value, const void *params) +{ + (void)params; + int v = *(int*)value; + return v >= 0; +} + +static const var_type_fns_t memunit_fns = { + .parse = units_parse_u64, + .encode = uint64_encode, // doesn't use params + .clear = uint64_clear, // doesn't use params +}; + +static const var_type_fns_t interval_fns = { + .parse = units_parse_int, + .encode = int_encode, // doesn't use params + .clear = int_clear, // doesn't use params, + .ok = units_ok_int // can't use int_ok, since that expects int params. +}; + +///// +// CONFIG_TYPE_DOUBLE +// +// This is a nice simple double. +///// + +static int +double_parse(void *target, const char *value, char **errmsg, + const void *params) +{ + (void)params; + (void)errmsg; + double *v = (double*)target; + char *endptr=NULL; + errno = 0; + *v = strtod(value, &endptr); + if (endptr == value || *endptr != '\0') { + // Either there are no converted characters, or there were some characters + // that didn't get converted. + tor_asprintf(errmsg, "Could not convert %s to a number.", escaped(value)); + return -1; + } + if (errno == ERANGE) { + // strtod will set errno to ERANGE on underflow or overflow. + bool underflow = -.00001 < *v && *v < .00001; + tor_asprintf(errmsg, + "%s is too %s to express as a floating-point number.", + escaped(value), underflow ? "small" : "large"); + return -1; + } + return 0; +} + +static char * +double_encode(const void *value, const void *params) +{ + (void)params; + double v = *(double*)value; + char *result; + tor_asprintf(&result, "%f", v); + return result; +} + +static void +double_clear(void *value, const void *params) +{ + (void)params; + double *v = (double *)value; + *v = 0.0; +} + +static const var_type_fns_t double_fns = { + .parse = double_parse, + .encode = double_encode, + .clear = double_clear, +}; + +///// +// CONFIG_TYPE_BOOL +// CONFIG_TYPE_AUTOBOOL +// +// These types are implemented as a case-insensitive string-to-integer +// mapping. +///// + +typedef struct enumeration_table_t { + const char *name; + int value; +} enumeration_table_t; + +typedef struct enumeration_params_t { + const char *allowed_val_string; + const enumeration_table_t *table; +} enumeration_params_t; + +static int +enum_parse(void *target, const char *value, char **errmsg, + const void *params_) +{ + const enumeration_params_t *params = params_; + const enumeration_table_t *table = params->table; + int *p = (int *)target; + for (; table->name; ++table) { + if (!strcasecmp(value, table->name)) { + *p = table->value; + return 0; + } + } + tor_asprintf(errmsg, "Unrecognized value %s. %s", + value, params->allowed_val_string); + return -1; +} + +static char * +enum_encode(const void *value, const void *params_) +{ + int v = *(const int*)value; + const enumeration_params_t *params = params_; + const enumeration_table_t *table = params->table; + for (; table->name; ++table) { + if (v == table->value) + return tor_strdup(table->name); + } + return NULL; // error. +} + +static void +enum_clear(void *value, const void *params_) +{ + int *p = (int*)value; + const enumeration_params_t *params = params_; + const enumeration_table_t *table = params->table; + tor_assert(table->name); + *p = table->value; +} + +static bool +enum_ok(const void *value, const void *params_) +{ + int v = *(const int*)value; + const enumeration_params_t *params = params_; + const enumeration_table_t *table = params->table; + for (; table->name; ++table) { + if (v == table->value) + return true; + } + return false; +} + +static const enumeration_table_t enum_table_bool[] = { + { "0", 0 }, + { "1", 1 }, + { NULL, 0 }, +}; + +static const enumeration_params_t enum_params_bool = { + "Allowed values are 0 and 1.", + enum_table_bool +}; + +static const enumeration_table_t enum_table_autobool[] = { + { "0", 0 }, + { "1", 1 }, + { "auto", -1 }, + { NULL, 0 }, +}; + +static const enumeration_params_t enum_params_autobool = { + "Allowed values are 0, 1, and auto.", + enum_table_autobool +}; + +static const var_type_fns_t enum_fns = { + .parse = enum_parse, + .encode = enum_encode, + .clear = enum_clear, + .ok = enum_ok, +}; + +///// +// CONFIG_TYPE_ISOTIME +// +// This is a time_t, encoded in ISO8601 format. +///// + +static int +time_parse(void *target, const char *value, char **errmsg, + const void *params) +{ + (void) params; + time_t *p = target; + if (parse_iso_time(value, p) < 0) { + tor_asprintf(errmsg, "Invalid time %s", escaped(value)); + return -1; + } + return 0; +} + +static char * +time_encode(const void *value, const void *params) +{ + (void)params; + time_t v = *(const time_t *)value; + char *result = tor_malloc(ISO_TIME_LEN+1); + format_iso_time(result, v); + return result; +} + +static void +time_clear(void *value, const void *params) +{ + (void)params; + time_t *t = value; + *t = 0; +} + +static const var_type_fns_t time_fns = { + .parse = time_parse, + .encode = time_encode, + .clear = time_clear, +}; + +///// +// CONFIG_TYPE_CSV +// +// This type is a comma-separated list of strings, stored in a smartlist_t. +// An empty list may be encoded either as an empty smartlist, or as NULL. +///// + +static int +csv_parse(void *target, const char *value, char **errmsg, + const void *params) +{ + (void)params; + (void)errmsg; + smartlist_t **sl = (smartlist_t**)target; + *sl = smartlist_new(); + smartlist_split_string(*sl, value, ",", + SPLIT_SKIP_SPACE|SPLIT_IGNORE_BLANK, 0); + return 0; +} + +static char * +csv_encode(const void *value, const void *params) +{ + (void)params; + const smartlist_t *sl = *(const smartlist_t **)value; + if (! sl) + return tor_strdup(""); + + return smartlist_join_strings(*(smartlist_t**)value, ",", 0, NULL); +} + +static void +csv_clear(void *value, const void *params) +{ + (void)params; + smartlist_t **sl = (smartlist_t**)value; + if (!*sl) + return; + SMARTLIST_FOREACH(*sl, char *, cp, tor_free(cp)); + smartlist_free(*sl); // clears pointer. +} + +static const var_type_fns_t csv_fns = { + .parse = csv_parse, + .encode = csv_encode, + .clear = csv_clear, +}; + +///// +// CONFIG_TYPE_CSV_INTERVAL +// +// This type used to be a list of time intervals, used to determine a download +// schedule. Now, only the first interval counts: everything after the first +// comma is discarded. +///// + +static int +legacy_csv_interval_parse(void *target, const char *value, char **errmsg, + const void *params) +{ + (void)params; + /* We used to have entire smartlists here. But now that all of our + * download schedules use exponential backoff, only the first part + * matters. */ + const char *comma = strchr(value, ','); + const char *val = value; + char *tmp = NULL; + if (comma) { + tmp = tor_strndup(val, comma - val); + val = tmp; + } + + int rv = units_parse_int(target, val, errmsg, &time_units); + tor_free(tmp); + return rv; +} + +static const var_type_fns_t legacy_csv_interval_fns = { + .parse = legacy_csv_interval_parse, + .encode = int_encode, + .clear = int_clear, +}; + +///// +// CONFIG_TYPE_LINELIST +// CONFIG_TYPE_LINELIST_S +// CONFIG_TYPE_LINELIST_V +// +// A linelist is a raw config_line_t list. Order is preserved. +// +// The LINELIST type is used for homogeneous lists, where all the lines +// have the same key. +// +// The LINELIST_S and LINELIST_V types are used for the case where multiple +// lines of different keys are kept in a single list, to preserve their +// relative order. The unified list is stored as a "virtual" variable whose +// type is LINELIST_V; the individual sublists are treated as variables of +// type LINELIST_S. +// +// A linelist may be fragile or non-fragile. Assigning a line to a fragile +// linelist replaces the list with the line. If the line has the "APPEND" +// command set on it, or if the list is non-fragile, the line is appended. +// Either way, the new list is non-fragile. +///// + +static int +linelist_kv_parse(void *target, const struct config_line_t *line, + char **errmsg, const void *params) +{ + (void)params; + (void)errmsg; + config_line_t **lines = target; + + if (*lines && (*lines)->fragile) { + if (line->command == CONFIG_LINE_APPEND) { + (*lines)->fragile = 0; + } else { + config_free_lines(*lines); // sets it to NULL + } + } + + config_line_append(lines, line->key, line->value); + return 0; +} + +static int +linelist_kv_virt_noparse(void *target, const struct config_line_t *line, + char **errmsg, const void *params) +{ + (void)target; + (void)line; + (void)params; + *errmsg = tor_strdup("Cannot assign directly to virtual option."); + return -1; +} + +static struct config_line_t * +linelist_kv_encode(const char *key, const void *value, + const void *params) +{ + (void)key; + (void)params; + config_line_t *lines = *(config_line_t **)value; + return config_lines_dup(lines); +} + +static struct config_line_t * +linelist_s_kv_encode(const char *key, const void *value, + const void *params) +{ + (void)params; + config_line_t *lines = *(config_line_t **)value; + return config_lines_dup_and_filter(lines, key); +} + +static void +linelist_clear(void *target, const void *params) +{ + (void)params; + config_line_t **lines = target; + config_free_lines(*lines); // sets it to NULL +} + +static bool +linelist_eq(const void *a, const void *b, const void *params) +{ + (void)params; + const config_line_t *lines_a = *(const config_line_t **)a; + const config_line_t *lines_b = *(const config_line_t **)b; + return config_lines_eq(lines_a, lines_b); +} + +static int +linelist_copy(void *target, const void *value, const void *params) +{ + (void)params; + config_line_t **ptr = (config_line_t **)target; + const config_line_t *val = *(const config_line_t **)value; + config_free_lines(*ptr); + *ptr = config_lines_dup(val); + return 0; +} + +static void +linelist_mark_fragile(void *target, const void *params) +{ + (void)params; + config_line_t **ptr = (config_line_t **)target; + if (*ptr) + (*ptr)->fragile = 1; +} + +static const var_type_fns_t linelist_fns = { + .kv_parse = linelist_kv_parse, + .kv_encode = linelist_kv_encode, + .clear = linelist_clear, + .eq = linelist_eq, + .copy = linelist_copy, + .mark_fragile = linelist_mark_fragile, +}; + +static const var_type_fns_t linelist_v_fns = { + .kv_parse = linelist_kv_virt_noparse, + .kv_encode = linelist_kv_encode, + .clear = linelist_clear, + .eq = linelist_eq, + .copy = linelist_copy, + .mark_fragile = linelist_mark_fragile, +}; + +static const var_type_fns_t linelist_s_fns = { + .kv_parse = linelist_kv_parse, + .kv_encode = linelist_s_kv_encode, + .clear = linelist_clear, + .eq = linelist_eq, + .copy = linelist_copy, +}; + +///// +// CONFIG_TYPE_ROUTERSET +// +// XXXX to this module. +///// + +///// +// CONFIG_TYPE_IGNORE +// +// Used to indicate an option that cannot be stored or encoded. +///// + +static int +ignore_parse(void *target, const char *value, char **errmsg, + const void *params) +{ + (void)target; + (void)value; + (void)errmsg; + (void)params; + return 0; +} + +static char * +ignore_encode(const void *value, const void *params) +{ + (void)value; + (void)params; + return NULL; +} + +static const var_type_fns_t ignore_fns = { + .parse = ignore_parse, + .encode = ignore_encode, +}; + +const var_type_def_t STRING_type_defn = { + .name="String", .fns=&string_fns }; +const var_type_def_t FILENAME_type_defn = { + .name="Filename", .fns=&string_fns }; +const var_type_def_t INT_type_defn = { + .name="SignedInteger", .fns=&int_fns, + .params=&INT_PARSE_UNRESTRICTED }; +const var_type_def_t POSINT_type_defn = { + .name="Integer", .fns=&int_fns, + .params=&INT_PARSE_POSINT }; +const var_type_def_t UINT64_type_defn = { + .name="Integer", .fns=&uint64_fns, }; +const var_type_def_t MEMUNIT_type_defn = { + .name="DataSize", .fns=&memunit_fns, + .params=&memory_units }; +const var_type_def_t INTERVAL_type_defn = { + .name="TimeInterval", .fns=&interval_fns, + .params=&time_units }; +const var_type_def_t MSEC_INTERVAL_type_defn = { + .name="TimeMsecInterval", + .fns=&interval_fns, + .params=&time_msec_units }; +const var_type_def_t DOUBLE_type_defn = { + .name="Float", .fns=&double_fns, }; +const var_type_def_t BOOL_type_defn = { + .name="Boolean", .fns=&enum_fns, + .params=&enum_params_bool }; +const var_type_def_t AUTOBOOL_type_defn = { + .name="Boolean+Auto", .fns=&enum_fns, + .params=&enum_params_autobool }; +const var_type_def_t ISOTIME_type_defn = { + .name="Time", .fns=&time_fns, }; +const var_type_def_t CSV_type_defn = { + .name="CommaList", .fns=&csv_fns, }; +const var_type_def_t CSV_INTERVAL_type_defn = { + .name="TimeInterval", + .fns=&legacy_csv_interval_fns, }; +const var_type_def_t LINELIST_type_defn = { + .name="LineList", .fns=&linelist_fns, + .flags=CFLG_NOREPLACE }; +/* + * A "linelist_s" is a derived view of a linelist_v: inspecting + * it gets part of a linelist_v, and setting it adds to the linelist_v. + */ +const var_type_def_t LINELIST_S_type_defn = { + .name="Dependent", .fns=&linelist_s_fns, + .flags=CFLG_NOREPLACE| + /* The operations we disable here are + * handled by the linelist_v. */ + CFLG_NOCOPY|CFLG_NOCMP|CFLG_NODUMP }; +const var_type_def_t LINELIST_V_type_defn = { + .name="Virtual", .fns=&linelist_v_fns, + .flags=CFLG_NOREPLACE|CFLG_NOSET }; +const var_type_def_t IGNORE_type_defn = { + .name="Ignored", .fns=&ignore_fns, + .flags=CFLG_NOCOPY|CFLG_NOCMP|CFLG_NODUMP|CFLG_NOSET, +}; +const var_type_def_t OBSOLETE_type_defn = { + .name="Obsolete", .fns=&ignore_fns, + .flags=CFLG_GROUP_OBSOLETE, +}; + +/** + * Table mapping conf_type_t values to var_type_def_t objects. + **/ +static const var_type_def_t *type_definitions_table[] = { + [CONFIG_TYPE_STRING] = &STRING_type_defn, + [CONFIG_TYPE_FILENAME] = &FILENAME_type_defn, + [CONFIG_TYPE_INT] = &INT_type_defn, + [CONFIG_TYPE_POSINT] = &POSINT_type_defn, + [CONFIG_TYPE_UINT64] = &UINT64_type_defn, + [CONFIG_TYPE_MEMUNIT] = &MEMUNIT_type_defn, + [CONFIG_TYPE_INTERVAL] = &INTERVAL_type_defn, + [CONFIG_TYPE_MSEC_INTERVAL] = &MSEC_INTERVAL_type_defn, + [CONFIG_TYPE_DOUBLE] = &DOUBLE_type_defn, + [CONFIG_TYPE_BOOL] = &BOOL_type_defn, + [CONFIG_TYPE_AUTOBOOL] = &AUTOBOOL_type_defn, + [CONFIG_TYPE_ISOTIME] = &ISOTIME_type_defn, + [CONFIG_TYPE_CSV] = &CSV_type_defn, + [CONFIG_TYPE_CSV_INTERVAL] = &CSV_INTERVAL_type_defn, + [CONFIG_TYPE_LINELIST] = &LINELIST_type_defn, + [CONFIG_TYPE_LINELIST_S] = &LINELIST_S_type_defn, + [CONFIG_TYPE_LINELIST_V] = &LINELIST_V_type_defn, + [CONFIG_TYPE_IGNORE] = &IGNORE_type_defn, + [CONFIG_TYPE_OBSOLETE] = &OBSOLETE_type_defn, +}; + +/** + * Return a pointer to the var_type_def_t object for the given + * config_type_t value, or NULL if no such type definition exists. + **/ +const var_type_def_t * +lookup_type_def(config_type_t type) +{ + int t = type; + tor_assert(t >= 0); + if (t >= (int)ARRAY_LENGTH(type_definitions_table)) + return NULL; + return type_definitions_table[t]; +} diff --git a/src/lib/confmgt/type_defs.h b/src/lib/confmgt/type_defs.h new file mode 100644 index 0000000000..fec002b1d3 --- /dev/null +++ b/src/lib/confmgt/type_defs.h @@ -0,0 +1,17 @@ +/* Copyright (c) 2001 Matej Pfajfar. + * Copyright (c) 2001-2004, Roger Dingledine. + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2020, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * @file type_defs.h + * @brief Header for lib/confmgt/type_defs.c + **/ + +#ifndef TOR_LIB_CONFMGT_TYPE_DEFS_H +#define TOR_LIB_CONFMGT_TYPE_DEFS_H + +const struct var_type_def_t *lookup_type_def(config_type_t type); + +#endif /* !defined(TOR_LIB_CONFMGT_TYPE_DEFS_H) */ diff --git a/src/lib/confmgt/typedvar.c b/src/lib/confmgt/typedvar.c new file mode 100644 index 0000000000..1955302cdc --- /dev/null +++ b/src/lib/confmgt/typedvar.c @@ -0,0 +1,236 @@ +/* Copyright (c) 2001 Matej Pfajfar. + * Copyright (c) 2001-2004, Roger Dingledine. + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2020, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * @file typedvar.c + * @brief Functions for accessing a pointer as an object of a given type. + * + * These functions represent a low-level API for accessing a typed variable. + * They are used in the configuration system to examine and set fields in + * configuration objects used by individual modules. + * + * Almost no code should call these directly. + **/ + +#include "orconfig.h" +#include "lib/conf/conftypes.h" +#include "lib/confmgt/type_defs.h" +#include "lib/confmgt/typedvar.h" +#include "lib/encoding/confline.h" +#include "lib/log/escape.h" +#include "lib/log/log.h" +#include "lib/log/util_bug.h" +#include "lib/malloc/malloc.h" +#include "lib/string/printf.h" +#include "lib/string/util_string.h" + +#include "lib/confmgt/var_type_def_st.h" + +#include <stddef.h> +#include <string.h> + +/** + * Try to parse a string in <b>value</b> that encodes an object of the type + * defined by <b>def</b>. + * + * On success, adjust the lvalue pointed to by <b>target</b> to hold that + * value, and return 0. On failure, set *<b>errmsg</b> to a newly allocated + * string holding an error message, and return -1. + **/ +int +typed_var_assign(void *target, const char *value, char **errmsg, + const var_type_def_t *def) +{ + if (BUG(!def)) + return -1; // LCOV_EXCL_LINE + // clear old value if needed. + typed_var_free(target, def); + + tor_assert(def->fns->parse); + return def->fns->parse(target, value, errmsg, def->params); +} + +/** + * Try to parse a single line from the head of<b>line</b> that encodes an + * object of the type defined in <b>def</b>. On success and failure, behave as + * typed_var_assign(). + * + * All types for which keys are significant should use this function. + * + * Note that although multiple lines may be provided in <b>line</b>, + * only the first one is handled by this function. + **/ +int +typed_var_kvassign(void *target, const config_line_t *line, + char **errmsg, const var_type_def_t *def) +{ + if (BUG(!def)) + return -1; // LCOV_EXCL_LINE + + if (def->fns->kv_parse) { + // We do _not_ free the old value here, since linelist options + // sometimes have append semantics. + return def->fns->kv_parse(target, line, errmsg, def->params); + } + + int rv = typed_var_assign(target, line->value, errmsg, def); + if (rv < 0 && *errmsg != NULL) { + /* typed_var_assign() didn't know the line's keyword, but we do. + * Let's add it to the error message. */ + char *oldmsg = *errmsg; + tor_asprintf(errmsg, "Could not parse %s: %s", line->key, oldmsg); + tor_free(oldmsg); + } + return rv; +} + +/** + * Release storage held by a variable in <b>target</b> of type defined by + * <b>def</b>, and set <b>target</b> to a reasonable default. + **/ +void +typed_var_free(void *target, const var_type_def_t *def) +{ + if (BUG(!def)) + return; // LCOV_EXCL_LINE + if (def->fns->clear) { + def->fns->clear(target, def->params); + } +} + +/** + * Encode a value of type <b>def</b> pointed to by <b>value</b>, and return + * its result in a newly allocated string. The string may need to be escaped. + * + * Returns NULL if this option has a NULL value, or on internal error. + **/ +char * +typed_var_encode(const void *value, const var_type_def_t *def) +{ + if (BUG(!def)) + return NULL; // LCOV_EXCL_LINE + tor_assert(def->fns->encode); + return def->fns->encode(value, def->params); +} + +/** + * As typed_var_encode(), but returns a newly allocated config_line_t + * object. The provided <b>key</b> is used as the key of the lines, unless + * the type is one (line a linelist) that encodes its own keys. + * + * This function may return a list of multiple lines. + * + * Returns NULL if there are no lines to encode, or on internal error. + */ +config_line_t * +typed_var_kvencode(const char *key, const void *value, + const var_type_def_t *def) +{ + if (BUG(!def)) + return NULL; // LCOV_EXCL_LINE + if (def->fns->kv_encode) { + return def->fns->kv_encode(key, value, def->params); + } + char *encoded_value = typed_var_encode(value, def); + if (!encoded_value) + return NULL; + + config_line_t *result = tor_malloc_zero(sizeof(config_line_t)); + result->key = tor_strdup(key); + result->value = encoded_value; + return result; +} + +/** + * Set <b>dest</b> to contain the same value as <b>src</b>. Both types + * must be as defined by <b>def</b>. + * + * Return 0 on success, and -1 on failure. + **/ +int +typed_var_copy(void *dest, const void *src, const var_type_def_t *def) +{ + if (BUG(!def)) + return -1; // LCOV_EXCL_LINE + if (def->fns->copy) { + // If we have been provided a copy fuction, use it. + return def->fns->copy(dest, src, def); + } + + // Otherwise, encode 'src' and parse the result into 'def'. + char *enc = typed_var_encode(src, def); + if (!enc) { + typed_var_free(dest, def); + return 0; + } + char *err = NULL; + int rv = typed_var_assign(dest, enc, &err, def); + if (BUG(rv < 0)) { + // LCOV_EXCL_START + log_warn(LD_BUG, "Encoded value %s was not parseable as a %s: %s", + escaped(enc), def->name, err?err:""); + // LCOV_EXCL_STOP + } + tor_free(err); + tor_free(enc); + return rv; +} + +/** + * Return true if <b>a</b> and <b>b</b> are semantically equivalent. + * Both types must be as defined by <b>def</b>. + **/ +bool +typed_var_eq(const void *a, const void *b, const var_type_def_t *def) +{ + if (BUG(!def)) + return false; // LCOV_EXCL_LINE + + if (def->fns->eq) { + // Use a provided eq function if we got one. + return def->fns->eq(a, b, def->params); + } + + // Otherwise, encode the values and compare them. + char *enc_a = typed_var_encode(a, def); + char *enc_b = typed_var_encode(b, def); + bool eq = !strcmp_opt(enc_a,enc_b); + tor_free(enc_a); + tor_free(enc_b); + return eq; +} + +/** + * Check whether <b>value</b> encodes a valid value according to the + * type definition in <b>def</b>. + */ +bool +typed_var_ok(const void *value, const var_type_def_t *def) +{ + if (BUG(!def)) + return false; // LCOV_EXCL_LINE + + if (def->fns->ok) + return def->fns->ok(value, def->params); + + return true; +} + +/** + * Mark <b>value</b> -- a variable that ordinarily would be extended by + * assignment -- as "fragile", so that it will get replaced by the next + * assignment instead. + **/ +void +typed_var_mark_fragile(void *value, const var_type_def_t *def) +{ + if (BUG(!def)) { + return; // LCOV_EXCL_LINE + } + + if (def->fns->mark_fragile) + def->fns->mark_fragile(value, def->params); +} diff --git a/src/lib/confmgt/typedvar.h b/src/lib/confmgt/typedvar.h new file mode 100644 index 0000000000..cc90ed10a3 --- /dev/null +++ b/src/lib/confmgt/typedvar.h @@ -0,0 +1,38 @@ +/* Copyright (c) 2001 Matej Pfajfar. + * Copyright (c) 2001-2004, Roger Dingledine. + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2020, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * @file typedvar.h + * @brief Header for lib/confmgt/typedvar.c + **/ + +#ifndef TOR_LIB_CONFMGT_TYPEDVAR_H +#define TOR_LIB_CONFMGT_TYPEDVAR_H + +#include <stdbool.h> + +enum config_type_t; +struct config_line_t; + +typedef struct var_type_fns_t var_type_fns_t; +typedef struct var_type_def_t var_type_def_t; + +int typed_var_assign(void *target, const char *value, char **errmsg, + const var_type_def_t *def); +void typed_var_free(void *target, const var_type_def_t *def); +char *typed_var_encode(const void *value, const var_type_def_t *def); +int typed_var_copy(void *dest, const void *src, const var_type_def_t *def); +bool typed_var_eq(const void *a, const void *b, const var_type_def_t *def); +bool typed_var_ok(const void *value, const var_type_def_t *def); + +int typed_var_kvassign(void *target, const struct config_line_t *line, + char **errmsg, const var_type_def_t *def); +struct config_line_t *typed_var_kvencode(const char *key, const void *value, + const var_type_def_t *def); + +void typed_var_mark_fragile(void *value, const var_type_def_t *def); + +#endif /* !defined(TOR_LIB_CONFMGT_TYPEDVAR_H) */ diff --git a/src/lib/confmgt/unitparse.c b/src/lib/confmgt/unitparse.c new file mode 100644 index 0000000000..99716e8d9d --- /dev/null +++ b/src/lib/confmgt/unitparse.c @@ -0,0 +1,260 @@ +/* Copyright (c) 2001 Matej Pfajfar. + * Copyright (c) 2001-2004, Roger Dingledine. + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2020, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * @file unitparse.c + * @brief Functions for parsing values with units from a configuration file. + **/ + +#include "orconfig.h" +#include "lib/confmgt/unitparse.h" +#include "lib/log/log.h" +#include "lib/log/util_bug.h" +#include "lib/malloc/malloc.h" +#include "lib/string/parse_int.h" +#include "lib/string/printf.h" +#include "lib/string/util_string.h" +#include "lib/intmath/muldiv.h" + +#include <string.h> + +/** Table to map the names of memory units to the number of bytes they + * contain. */ +// clang-format off +const struct unit_table_t memory_units[] = { + { "", 1 }, + { "b", 1<< 0 }, + { "byte", 1<< 0 }, + { "bytes", 1<< 0 }, + { "kb", 1<<10 }, + { "kbyte", 1<<10 }, + { "kbytes", 1<<10 }, + { "kilobyte", 1<<10 }, + { "kilobytes", 1<<10 }, + { "kilobits", 1<<7 }, + { "kilobit", 1<<7 }, + { "kbits", 1<<7 }, + { "kbit", 1<<7 }, + { "m", 1<<20 }, + { "mb", 1<<20 }, + { "mbyte", 1<<20 }, + { "mbytes", 1<<20 }, + { "megabyte", 1<<20 }, + { "megabytes", 1<<20 }, + { "megabits", 1<<17 }, + { "megabit", 1<<17 }, + { "mbits", 1<<17 }, + { "mbit", 1<<17 }, + { "gb", 1<<30 }, + { "gbyte", 1<<30 }, + { "gbytes", 1<<30 }, + { "gigabyte", 1<<30 }, + { "gigabytes", 1<<30 }, + { "gigabits", 1<<27 }, + { "gigabit", 1<<27 }, + { "gbits", 1<<27 }, + { "gbit", 1<<27 }, + { "tb", UINT64_C(1)<<40 }, + { "tbyte", UINT64_C(1)<<40 }, + { "tbytes", UINT64_C(1)<<40 }, + { "terabyte", UINT64_C(1)<<40 }, + { "terabytes", UINT64_C(1)<<40 }, + { "terabits", UINT64_C(1)<<37 }, + { "terabit", UINT64_C(1)<<37 }, + { "tbits", UINT64_C(1)<<37 }, + { "tbit", UINT64_C(1)<<37 }, + { NULL, 0 }, +}; +// clang-format on + +/** Table to map the names of time units to the number of seconds they + * contain. */ +// clang-format off +const struct unit_table_t time_units[] = { + { "", 1 }, + { "second", 1 }, + { "seconds", 1 }, + { "minute", 60 }, + { "minutes", 60 }, + { "hour", 60*60 }, + { "hours", 60*60 }, + { "day", 24*60*60 }, + { "days", 24*60*60 }, + { "week", 7*24*60*60 }, + { "weeks", 7*24*60*60 }, + { "month", 2629728, }, /* about 30.437 days */ + { "months", 2629728, }, + { NULL, 0 }, +}; +// clang-format on + +/** Table to map the names of time units to the number of milliseconds + * they contain. */ +// clang-format off +const struct unit_table_t time_msec_units[] = { + { "", 1 }, + { "msec", 1 }, + { "millisecond", 1 }, + { "milliseconds", 1 }, + { "second", 1000 }, + { "seconds", 1000 }, + { "minute", 60*1000 }, + { "minutes", 60*1000 }, + { "hour", 60*60*1000 }, + { "hours", 60*60*1000 }, + { "day", 24*60*60*1000 }, + { "days", 24*60*60*1000 }, + { "week", 7*24*60*60*1000 }, + { "weeks", 7*24*60*60*1000 }, + { NULL, 0 }, +}; +// clang-format on + +/** Parse a string <b>val</b> containing a number, zero or more + * spaces, and an optional unit string. If the unit appears in the + * table <b>u</b>, then multiply the number by the unit multiplier. + * On success, set *<b>ok</b> to 1 and return this product. + * Otherwise, set *<b>ok</b> to 0. + * + * If an error (like overflow or a negative value is detected), put an error + * message in *<b>errmsg_out</b> if that pointer is non-NULL, and otherwise + * log a warning. + */ +uint64_t +config_parse_units(const char *val, const unit_table_t *u, int *ok, + char **errmsg_out) +{ + uint64_t v = 0; + double d = 0; + int use_float = 0; + char *cp; + char *errmsg = NULL; + + tor_assert(ok); + + v = tor_parse_uint64(val, 10, 0, UINT64_MAX, ok, &cp); + if (!*ok || (cp && *cp == '.')) { + d = tor_parse_double(val, 0, (double)UINT64_MAX, ok, &cp); + if (!*ok) { + tor_asprintf(&errmsg, "Unable to parse %s as a number", val); + goto done; + } + use_float = 1; + } + + if (BUG(!cp)) { + // cp should always be non-NULL if the parse operation succeeds. + + // LCOV_EXCL_START + *ok = 1; + v = use_float ? ((uint64_t)d) : v; + goto done; + // LCOV_EXCL_STOP + } + + cp = (char*) eat_whitespace(cp); + + for ( ;u->unit;++u) { + if (!strcasecmp(u->unit, cp)) { + if (use_float) { + d = u->multiplier * d; + + if (d < 0) { + tor_asprintf(&errmsg, "Got a negative value while parsing %s %s", + val, u->unit); + *ok = 0; + goto done; + } + + // Some compilers may warn about casting a double to an unsigned type + // because they don't know if d is >= 0 + if (d >= 0 && (d > (double)INT64_MAX || (uint64_t)d > INT64_MAX)) { + tor_asprintf(&errmsg, "Overflow while parsing %s %s", + val, u->unit); + *ok = 0; + goto done; + } + + v = (uint64_t) d; + } else { + v = tor_mul_u64_nowrap(v, u->multiplier); + + if (v > INT64_MAX) { + tor_asprintf(&errmsg, "Overflow while parsing %s %s", + val, u->unit); + *ok = 0; + goto done; + } + } + + *ok = 1; + goto done; + } + } + tor_asprintf(&errmsg, "Unknown unit in %s", val); + *ok = 0; + done: + + if (errmsg) { + tor_assert_nonfatal(!*ok); + if (errmsg_out) { + *errmsg_out = errmsg; + } else { + log_warn(LD_CONFIG, "%s", errmsg); + tor_free(errmsg); + } + } + + if (*ok) + return v; + else + return 0; +} + +/** Parse a string in the format "number unit", where unit is a unit of + * information (byte, KB, M, etc). On success, set *<b>ok</b> to true + * and return the number of bytes specified. Otherwise, set + * *<b>ok</b> to false and return 0. */ +uint64_t +config_parse_memunit(const char *s, int *ok) +{ + uint64_t u = config_parse_units(s, memory_units, ok, NULL); + return u; +} + +/** Parse a string in the format "number unit", where unit is a unit of + * time in milliseconds. On success, set *<b>ok</b> to true and return + * the number of milliseconds in the provided interval. Otherwise, set + * *<b>ok</b> to 0 and return -1. */ +int +config_parse_msec_interval(const char *s, int *ok) +{ + uint64_t r; + r = config_parse_units(s, time_msec_units, ok, NULL); + if (r > INT_MAX) { + log_warn(LD_CONFIG, "Msec interval '%s' is too long", s); + *ok = 0; + return -1; + } + return (int)r; +} + +/** Parse a string in the format "number unit", where unit is a unit of time. + * On success, set *<b>ok</b> to true and return the number of seconds in + * the provided interval. Otherwise, set *<b>ok</b> to 0 and return -1. + */ +int +config_parse_interval(const char *s, int *ok) +{ + uint64_t r; + r = config_parse_units(s, time_units, ok, NULL); + if (r > INT_MAX) { + log_warn(LD_CONFIG, "Interval '%s' is too long", s); + *ok = 0; + return -1; + } + return (int)r; +} diff --git a/src/lib/confmgt/unitparse.h b/src/lib/confmgt/unitparse.h new file mode 100644 index 0000000000..047e11b424 --- /dev/null +++ b/src/lib/confmgt/unitparse.h @@ -0,0 +1,35 @@ +/* Copyright (c) 2001 Matej Pfajfar. + * Copyright (c) 2001-2004, Roger Dingledine. + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2020, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * @file unitparse.h + * @brief Header for lib/confmgt/unitparse.c + **/ + +#ifndef TOR_LIB_CONFMGT_UNITPARSE_H +#define TOR_LIB_CONFMGT_UNITPARSE_H + +#include <lib/cc/torint.h> + +/** Mapping from a unit name to a multiplier for converting that unit into a + * base unit. Used by config_parse_unit. */ +typedef struct unit_table_t { + const char *unit; /**< The name of the unit */ + uint64_t multiplier; /**< How many of the base unit appear in this unit */ +} unit_table_t; + +extern const unit_table_t memory_units[]; +extern const unit_table_t time_units[]; +extern const struct unit_table_t time_msec_units[]; + +uint64_t config_parse_units(const char *val, const unit_table_t *u, int *ok, + char **errmsg_out); + +uint64_t config_parse_memunit(const char *s, int *ok); +int config_parse_msec_interval(const char *s, int *ok); +int config_parse_interval(const char *s, int *ok); + +#endif /* !defined(TOR_LIB_CONFMGT_UNITPARSE_H) */ diff --git a/src/lib/confmgt/var_type_def_st.h b/src/lib/confmgt/var_type_def_st.h new file mode 100644 index 0000000000..2519b86aa0 --- /dev/null +++ b/src/lib/confmgt/var_type_def_st.h @@ -0,0 +1,167 @@ +/* Copyright (c) 2001 Matej Pfajfar. + * Copyright (c) 2001-2004, Roger Dingledine. + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2020, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * @file var_type_def_st.h + * @brief Structure declarations for typedvar type definitions. + * + * This structure is used for defining new variable types. If you are not + * defining a new variable type for use by the configuration management + * system, you don't need this structure. + * + * For defining new variables, see the types in conftypes.h. + * + * For data-driven access to configuration variables, see the other members of + * lib/confmgt/. + * + * STATUS NOTE: It is not yet possible to actually define new variables + * outside of config.c, and many of the types that will eventually be used + * to do so are not yet moved. This will change as more of #29211 is + * completed. + **/ + +#ifndef TOR_LIB_CONFMGT_VAR_TYPE_DEF_ST_H +#define TOR_LIB_CONFMGT_VAR_TYPE_DEF_ST_H + +#include <stdbool.h> + +struct config_line_t; + +/** + * A structure full of functions pointers to implement a variable type. + * + * Every type MUST implement parse or kv_parse and encode or kv_encode; + * the other functions pointers MAY be NULL. + * + * All functions here take a <b>params</b> argument, whose value + * is determined by the type definition. Two types may have the + * same functions, but differ only in parameters. + * + * Implementation considerations: If "" encodes a valid value for a type, try + * to make sure that it encodes the same thing as the default value for the + * type (that is, the value that is set by config_clear() or memset(0)). If + * this is not the case, you need to make extra certain that your parse/encode + * implementations preserve the NULL/"" distinction. + **/ +struct var_type_fns_t { + /** + * Try to parse a string in <b>value</b> that encodes an object of this + * type. On success, adjust the lvalue pointed to by <b>target</b> to hold + * that value, and return 0. On failure, set *<b>errmsg</b> to a newly + * allocated string holding an error message, and return -1. + **/ + int (*parse)(void *target, const char *value, char **errmsg, + const void *params); + /** + * Try to parse a single line from the head of<b>line</b> that encodes + * an object of this type. On success and failure, behave as in the parse() + * function. + * + * If this function is absent, it is implemented in terms of parse(). + * + * All types for which keys are significant should use this method. For + * example, a "linelist" type records the actual keys that are given + * for each line, and so should use this method. + * + * Note that although multiple lines may be provided in <b>line</b>, + * only the first one should be handled by this function. + **/ + int (*kv_parse)(void *target, const struct config_line_t *line, + char **errmsg, const void *params); + /** + * Encode a value pointed to by <b>value</b> and return its result + * in a newly allocated string. The string may need to be escaped. + * + * If this function is absent, it is implemented in terms of kv_encode(). + * + * Returns NULL if this option has a NULL value, or on internal error. + * + * Requirement: all strings generated by encode() should produce a + * semantically equivalent value when given to parse(). + **/ + char *(*encode)(const void *value, const void *params); + /** + * As encode(), but returns a newly allocated config_line_t object. The + * provided <b>key</b> is used as the key of the lines, unless the type is + * one that encodes its own keys. + * + * Unlike kv_parse(), this function will return a list of multiple lines, + * if <b>value</b> is such that it must be encoded by multiple lines. + * + * Returns NULL if there are no lines to encode, or on internal error. + * + * If this function is absent, it is implemented in terms of encode(). + **/ + struct config_line_t *(*kv_encode)(const char *key, const void *value, + const void *params); + /** + * Free all storage held in <b>arg</b>, and set <b>arg</b> to a default + * value -- usually zero or NULL. + * + * If this function is absent, the default implementation does nothing. + **/ + void (*clear)(void *arg, const void *params); + /** + * Return true if <b>a</b> and <b>b</b> hold the same value, and false + * otherwise. + * + * If this function is absent, it is implemented by encoding both a and + * b and comparing their encoded strings for equality. + **/ + bool (*eq)(const void *a, const void *b, const void *params); + /** + * Try to copy the value from <b>value</b> into <b>target</b>. + * On success return 0; on failure return -1. + * + * If this function is absent, it is implemented by encoding the value + * into a string, and then parsing it into the target. + **/ + int (*copy)(void *target, const void *value, const void *params); + /** + * Check whether <b>value</b> holds a valid value according to the + * rules of this type; return true if it does and false if it doesn't. + * + * The default implementation for this function assumes that all + * values are valid. + **/ + bool (*ok)(const void *value, const void *params); + /** + * Mark a value of this variable as "fragile", so that future attempts to + * assign to this variable will replace rather than extending it. + * + * The default implementation for this function does nothing. + * + * Only meaningful for types with is_cumulative set. + **/ + void (*mark_fragile)(void *value, const void *params); +}; + +/** + * A structure describing a type that can be manipulated with the typedvar_* + * functions. + **/ +struct var_type_def_t { + /** + * The name of this type. Should not include spaces. Used for + * debugging, log messages, and the controller API. */ + const char *name; + /** + * A function table for this type. + */ + const struct var_type_fns_t *fns; + /** + * A pointer to a value that should be passed as the 'params' argument when + * calling the functions in this type's function table. + */ + const void *params; + /** + * A bitwise OR of one or more VTFLAG_* values, describing properties + * for all values of this type. + **/ + uint32_t flags; +}; + +#endif /* !defined(TOR_LIB_CONFMGT_VAR_TYPE_DEF_ST_H) */ |