environment.con commit t1501: demonstrate NULL pointer access with invalid GIT_WORK_TREE (aac3eaa)
   1/*
   2 * We put all the git config variables in this same object
   3 * file, so that programs can link against the config parser
   4 * without having to link against all the rest of git.
   5 *
   6 * In particular, no need to bring in libz etc unless needed,
   7 * even if you might want to know where the git directory etc
   8 * are.
   9 */
  10#include "cache.h"
  11#include "refs.h"
  12#include "fmt-merge-msg.h"
  13#include "commit.h"
  14
  15int trust_executable_bit = 1;
  16int trust_ctime = 1;
  17int check_stat = 1;
  18int has_symlinks = 1;
  19int minimum_abbrev = 4, default_abbrev = -1;
  20int ignore_case;
  21int assume_unchanged;
  22int prefer_symlink_refs;
  23int is_bare_repository_cfg = -1; /* unspecified */
  24int warn_ambiguous_refs = 1;
  25int warn_on_object_refname_ambiguity = 1;
  26int ref_paranoia = -1;
  27int repository_format_precious_objects;
  28const char *git_commit_encoding;
  29const char *git_log_output_encoding;
  30const char *apply_default_whitespace;
  31const char *apply_default_ignorewhitespace;
  32const char *git_attributes_file;
  33const char *git_hooks_path;
  34int zlib_compression_level = Z_BEST_SPEED;
  35int core_compression_level;
  36int pack_compression_level = Z_DEFAULT_COMPRESSION;
  37int fsync_object_files;
  38size_t packed_git_window_size = DEFAULT_PACKED_GIT_WINDOW_SIZE;
  39size_t packed_git_limit = DEFAULT_PACKED_GIT_LIMIT;
  40size_t delta_base_cache_limit = 96 * 1024 * 1024;
  41unsigned long big_file_threshold = 512 * 1024 * 1024;
  42int pager_use_color = 1;
  43const char *editor_program;
  44const char *askpass_program;
  45const char *excludes_file;
  46enum auto_crlf auto_crlf = AUTO_CRLF_FALSE;
  47int check_replace_refs = 1;
  48char *git_replace_ref_base;
  49enum eol core_eol = EOL_UNSET;
  50enum safe_crlf safe_crlf = SAFE_CRLF_WARN;
  51unsigned whitespace_rule_cfg = WS_DEFAULT_RULE;
  52enum branch_track git_branch_track = BRANCH_TRACK_REMOTE;
  53enum rebase_setup_type autorebase = AUTOREBASE_NEVER;
  54enum push_default_type push_default = PUSH_DEFAULT_UNSPECIFIED;
  55#ifndef OBJECT_CREATION_MODE
  56#define OBJECT_CREATION_MODE OBJECT_CREATION_USES_HARDLINKS
  57#endif
  58enum object_creation_mode object_creation_mode = OBJECT_CREATION_MODE;
  59char *notes_ref_name;
  60int grafts_replace_parents = 1;
  61int core_apply_sparse_checkout;
  62int merge_log_config = -1;
  63int precomposed_unicode = -1; /* see probe_utf8_pathname_composition() */
  64unsigned long pack_size_limit_cfg;
  65enum hide_dotfiles_type hide_dotfiles = HIDE_DOTFILES_DOTGITONLY;
  66enum log_refs_config log_all_ref_updates = LOG_REFS_UNSET;
  67
  68#ifndef PROTECT_HFS_DEFAULT
  69#define PROTECT_HFS_DEFAULT 0
  70#endif
  71int protect_hfs = PROTECT_HFS_DEFAULT;
  72
  73#ifndef PROTECT_NTFS_DEFAULT
  74#define PROTECT_NTFS_DEFAULT 0
  75#endif
  76int protect_ntfs = PROTECT_NTFS_DEFAULT;
  77
  78/*
  79 * The character that begins a commented line in user-editable file
  80 * that is subject to stripspace.
  81 */
  82char comment_line_char = '#';
  83int auto_comment_line_char;
  84
  85/* Parallel index stat data preload? */
  86int core_preload_index = 1;
  87
  88/*
  89 * This is a hack for test programs like test-dump-untracked-cache to
  90 * ensure that they do not modify the untracked cache when reading it.
  91 * Do not use it otherwise!
  92 */
  93int ignore_untracked_cache_config;
  94
  95/* This is set by setup_git_dir_gently() and/or git_default_config() */
  96char *git_work_tree_cfg;
  97static char *work_tree;
  98
  99static const char *namespace;
 100static size_t namespace_len;
 101
 102static const char *super_prefix;
 103
 104static const char *git_dir, *git_common_dir;
 105static char *git_object_dir, *git_index_file, *git_graft_file;
 106int git_db_env, git_index_env, git_graft_env, git_common_dir_env;
 107
 108/*
 109 * Repository-local GIT_* environment variables; see cache.h for details.
 110 */
 111const char * const local_repo_env[] = {
 112        ALTERNATE_DB_ENVIRONMENT,
 113        CONFIG_ENVIRONMENT,
 114        CONFIG_DATA_ENVIRONMENT,
 115        DB_ENVIRONMENT,
 116        GIT_DIR_ENVIRONMENT,
 117        GIT_WORK_TREE_ENVIRONMENT,
 118        GIT_IMPLICIT_WORK_TREE_ENVIRONMENT,
 119        GRAFT_ENVIRONMENT,
 120        INDEX_ENVIRONMENT,
 121        NO_REPLACE_OBJECTS_ENVIRONMENT,
 122        GIT_REPLACE_REF_BASE_ENVIRONMENT,
 123        GIT_PREFIX_ENVIRONMENT,
 124        GIT_SUPER_PREFIX_ENVIRONMENT,
 125        GIT_SHALLOW_FILE_ENVIRONMENT,
 126        GIT_COMMON_DIR_ENVIRONMENT,
 127        NULL
 128};
 129
 130static char *expand_namespace(const char *raw_namespace)
 131{
 132        struct strbuf buf = STRBUF_INIT;
 133        struct strbuf **components, **c;
 134
 135        if (!raw_namespace || !*raw_namespace)
 136                return xstrdup("");
 137
 138        strbuf_addstr(&buf, raw_namespace);
 139        components = strbuf_split(&buf, '/');
 140        strbuf_reset(&buf);
 141        for (c = components; *c; c++)
 142                if (strcmp((*c)->buf, "/") != 0)
 143                        strbuf_addf(&buf, "refs/namespaces/%s", (*c)->buf);
 144        strbuf_list_free(components);
 145        if (check_refname_format(buf.buf, 0))
 146                die("bad git namespace path \"%s\"", raw_namespace);
 147        strbuf_addch(&buf, '/');
 148        return strbuf_detach(&buf, NULL);
 149}
 150
 151static char *git_path_from_env(const char *envvar, const char *git_dir,
 152                               const char *path, int *fromenv)
 153{
 154        const char *value = getenv(envvar);
 155        if (!value)
 156                return xstrfmt("%s/%s", git_dir, path);
 157        if (fromenv)
 158                *fromenv = 1;
 159        return xstrdup(value);
 160}
 161
 162static void setup_git_env(void)
 163{
 164        struct strbuf sb = STRBUF_INIT;
 165        const char *gitfile;
 166        const char *shallow_file;
 167        const char *replace_ref_base;
 168
 169        git_dir = getenv(GIT_DIR_ENVIRONMENT);
 170        if (!git_dir)
 171                git_dir = DEFAULT_GIT_DIR_ENVIRONMENT;
 172        gitfile = read_gitfile(git_dir);
 173        git_dir = xstrdup(gitfile ? gitfile : git_dir);
 174        if (get_common_dir(&sb, git_dir))
 175                git_common_dir_env = 1;
 176        git_common_dir = strbuf_detach(&sb, NULL);
 177        git_object_dir = git_path_from_env(DB_ENVIRONMENT, git_common_dir,
 178                                           "objects", &git_db_env);
 179        git_index_file = git_path_from_env(INDEX_ENVIRONMENT, git_dir,
 180                                           "index", &git_index_env);
 181        git_graft_file = git_path_from_env(GRAFT_ENVIRONMENT, git_common_dir,
 182                                           "info/grafts", &git_graft_env);
 183        if (getenv(NO_REPLACE_OBJECTS_ENVIRONMENT))
 184                check_replace_refs = 0;
 185        replace_ref_base = getenv(GIT_REPLACE_REF_BASE_ENVIRONMENT);
 186        git_replace_ref_base = xstrdup(replace_ref_base ? replace_ref_base
 187                                                          : "refs/replace/");
 188        namespace = expand_namespace(getenv(GIT_NAMESPACE_ENVIRONMENT));
 189        namespace_len = strlen(namespace);
 190        shallow_file = getenv(GIT_SHALLOW_FILE_ENVIRONMENT);
 191        if (shallow_file)
 192                set_alternate_shallow_file(shallow_file, 0);
 193}
 194
 195int is_bare_repository(void)
 196{
 197        /* if core.bare is not 'false', let's see if there is a work tree */
 198        return is_bare_repository_cfg && !get_git_work_tree();
 199}
 200
 201int have_git_dir(void)
 202{
 203        return startup_info->have_repository
 204                || git_dir
 205                || getenv(GIT_DIR_ENVIRONMENT);
 206}
 207
 208const char *get_git_dir(void)
 209{
 210        if (!git_dir)
 211                setup_git_env();
 212        return git_dir;
 213}
 214
 215const char *get_git_common_dir(void)
 216{
 217        return git_common_dir;
 218}
 219
 220const char *get_git_namespace(void)
 221{
 222        if (!namespace)
 223                setup_git_env();
 224        return namespace;
 225}
 226
 227const char *strip_namespace(const char *namespaced_ref)
 228{
 229        if (!starts_with(namespaced_ref, get_git_namespace()))
 230                return NULL;
 231        return namespaced_ref + namespace_len;
 232}
 233
 234const char *get_super_prefix(void)
 235{
 236        static int initialized;
 237        if (!initialized) {
 238                super_prefix = getenv(GIT_SUPER_PREFIX_ENVIRONMENT);
 239                initialized = 1;
 240        }
 241        return super_prefix;
 242}
 243
 244static int git_work_tree_initialized;
 245
 246/*
 247 * Note.  This works only before you used a work tree.  This was added
 248 * primarily to support git-clone to work in a new repository it just
 249 * created, and is not meant to flip between different work trees.
 250 */
 251void set_git_work_tree(const char *new_work_tree)
 252{
 253        if (git_work_tree_initialized) {
 254                new_work_tree = real_path(new_work_tree);
 255                if (strcmp(new_work_tree, work_tree))
 256                        die("internal error: work tree has already been set\n"
 257                            "Current worktree: %s\nNew worktree: %s",
 258                            work_tree, new_work_tree);
 259                return;
 260        }
 261        git_work_tree_initialized = 1;
 262        work_tree = real_pathdup(new_work_tree);
 263}
 264
 265const char *get_git_work_tree(void)
 266{
 267        return work_tree;
 268}
 269
 270char *get_object_directory(void)
 271{
 272        if (!git_object_dir)
 273                setup_git_env();
 274        return git_object_dir;
 275}
 276
 277int odb_mkstemp(char *template, size_t limit, const char *pattern)
 278{
 279        int fd;
 280        /*
 281         * we let the umask do its job, don't try to be more
 282         * restrictive except to remove write permission.
 283         */
 284        int mode = 0444;
 285        snprintf(template, limit, "%s/%s",
 286                 get_object_directory(), pattern);
 287        fd = git_mkstemp_mode(template, mode);
 288        if (0 <= fd)
 289                return fd;
 290
 291        /* slow path */
 292        /* some mkstemp implementations erase template on failure */
 293        snprintf(template, limit, "%s/%s",
 294                 get_object_directory(), pattern);
 295        safe_create_leading_directories(template);
 296        return xmkstemp_mode(template, mode);
 297}
 298
 299int odb_pack_keep(char *name, size_t namesz, const unsigned char *sha1)
 300{
 301        int fd;
 302
 303        snprintf(name, namesz, "%s/pack/pack-%s.keep",
 304                 get_object_directory(), sha1_to_hex(sha1));
 305        fd = open(name, O_RDWR|O_CREAT|O_EXCL, 0600);
 306        if (0 <= fd)
 307                return fd;
 308
 309        /* slow path */
 310        safe_create_leading_directories(name);
 311        return open(name, O_RDWR|O_CREAT|O_EXCL, 0600);
 312}
 313
 314char *get_index_file(void)
 315{
 316        if (!git_index_file)
 317                setup_git_env();
 318        return git_index_file;
 319}
 320
 321char *get_graft_file(void)
 322{
 323        if (!git_graft_file)
 324                setup_git_env();
 325        return git_graft_file;
 326}
 327
 328int set_git_dir(const char *path)
 329{
 330        if (setenv(GIT_DIR_ENVIRONMENT, path, 1))
 331                return error("Could not set GIT_DIR to '%s'", path);
 332        setup_git_env();
 333        return 0;
 334}
 335
 336const char *get_log_output_encoding(void)
 337{
 338        return git_log_output_encoding ? git_log_output_encoding
 339                : get_commit_output_encoding();
 340}
 341
 342const char *get_commit_output_encoding(void)
 343{
 344        return git_commit_encoding ? git_commit_encoding : "UTF-8";
 345}
 346
 347static int the_shared_repository = PERM_UMASK;
 348static int need_shared_repository_from_config = 1;
 349
 350void set_shared_repository(int value)
 351{
 352        the_shared_repository = value;
 353        need_shared_repository_from_config = 0;
 354}
 355
 356int get_shared_repository(void)
 357{
 358        if (need_shared_repository_from_config) {
 359                const char *var = "core.sharedrepository";
 360                const char *value;
 361                if (!git_config_get_value(var, &value))
 362                        the_shared_repository = git_config_perm(var, value);
 363                need_shared_repository_from_config = 0;
 364        }
 365        return the_shared_repository;
 366}
 367
 368void reset_shared_repository(void)
 369{
 370        need_shared_repository_from_config = 1;
 371}