From: Denis Vlasenko Date: Wed, 22 Apr 2009 13:49:16 +0000 (-0000) Subject: httpd: simplify insane conf file parser X-Git-Tag: 1_15_0~291 X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=1cf4a0eb81ed85d222d3310c39ac89c84c13ca17;p=oweals%2Fbusybox.git httpd: simplify insane conf file parser function old new delta bb_simplify_abs_path_inplace - 98 +98 parse_expr 824 832 +8 passwd_main 1025 1027 +2 evalvar 1374 1376 +2 parse_command 1463 1460 -3 bb_simplify_path 137 55 -82 parse_conf 1572 1422 -150 ------------------------------------------------------------------------------ (add/remove: 3/2 grow/shrink: 3/3 up/down: 126/-251) Total: -125 bytes --- diff --git a/include/libbb.h b/include/libbb.h index 4de3e7915..3a94a0070 100644 --- a/include/libbb.h +++ b/include/libbb.h @@ -1093,6 +1093,8 @@ const char *get_signame(int number) FAST_FUNC; void print_signames(void) FAST_FUNC; char *bb_simplify_path(const char *path) FAST_FUNC; +/* Returns ptr to NUL */ +char *bb_simplify_abs_path_inplace(char *path) FAST_FUNC; #define FAIL_DELAY 3 extern void bb_do_delay(int seconds) FAST_FUNC; diff --git a/libbb/simplify_path.c b/libbb/simplify_path.c index 367f1f04d..f80e3e8a5 100644 --- a/libbb/simplify_path.c +++ b/libbb/simplify_path.c @@ -6,22 +6,13 @@ * * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. */ - #include "libbb.h" -char* FAST_FUNC bb_simplify_path(const char *path) +char* FAST_FUNC bb_simplify_abs_path_inplace(char *start) { - char *s, *start, *p; + char *s, *p; - if (path[0] == '/') - start = xstrdup(path); - else { - s = xrealloc_getcwd_or_warn(NULL); - start = concat_path_file(s, path); - free(s); - } p = s = start; - do { if (*p == '/') { if (*s == '/') { /* skip duplicate (or initial) slash */ @@ -47,7 +38,22 @@ char* FAST_FUNC bb_simplify_path(const char *path) if ((p == start) || (*p != '/')) { /* not a trailing slash */ ++p; /* so keep last character */ } - *p = 0; + *p = '\0'; + return p; +} + +char* FAST_FUNC bb_simplify_path(const char *path) +{ + char *s, *p; + + if (path[0] == '/') + s = xstrdup(path); + else { + p = xrealloc_getcwd_or_warn(NULL); + s = concat_path_file(p, path); + free(p); + } - return start; + bb_simplify_abs_path_inplace(s); + return s; } diff --git a/networking/httpd.c b/networking/httpd.c index 803a98b46..243d76f94 100644 --- a/networking/httpd.c +++ b/networking/httpd.c @@ -54,7 +54,7 @@ * /adm:admin:setup # Require user admin, pwd setup on urls starting with /adm/ * /adm:toor:PaSsWd # or user toor, pwd PaSsWd on urls starting with /adm/ * .au:audio/basic # additional mime type for audio.au files - * *.php:/path/php # running cgi.php scripts through an interpreter + * *.php:/path/php # run xxx.php through an interpreter * * A/D may be as a/d or allow/deny - only first char matters. * Deny/Allow IP logic: @@ -115,8 +115,8 @@ #define HEADER_READ_TIMEOUT 60 -static const char default_path_httpd_conf[] ALIGN1 = "/etc"; -static const char httpd_conf[] ALIGN1 = "httpd.conf"; +static const char DEFAULT_PATH_HTTPD_CONF[] ALIGN1 = "/etc"; +static const char HTTPD_CONF[] ALIGN1 = "httpd.conf"; static const char HTTP_200[] ALIGN1 = "HTTP/1.0 200 OK\r\n"; typedef struct has_next_ptr { @@ -242,7 +242,7 @@ struct globals { const char *bind_addr_or_port; const char *g_query; - const char *configFile; + const char *opt_c_configFile; const char *home_httpd; const char *index_page; @@ -289,7 +289,7 @@ struct globals { #define rmt_ip (G.rmt_ip ) #define bind_addr_or_port (G.bind_addr_or_port) #define g_query (G.g_query ) -#define configFile (G.configFile ) +#define opt_c_configFile (G.opt_c_configFile ) #define home_httpd (G.home_httpd ) #define index_page (G.index_page ) #define found_mime_type (G.found_mime_type ) @@ -452,14 +452,6 @@ static int scan_ip_mask(const char *str, unsigned *ipp, unsigned *maskp) /* * Parse configuration file into in-memory linked list. * - * The first non-white character is examined to determine if the config line - * is one of the following: - * .ext:mime/type # new mime type not compiled into httpd - * [adAD]:from # ip address allow/deny, * for wildcard - * /path:user:pass # username/password - * Ennn:error.html # error page for status nnn - * P:/url:[http://]hostname[:port]/new/path # reverse proxy - * * Any previous IP rules are discarded. * If the flag argument is not SUBDIR_PARSE then all /path and mime rules * are also discarded. That is, previous settings are retained if flag is @@ -469,99 +461,136 @@ static int scan_ip_mask(const char *str, unsigned *ipp, unsigned *maskp) * path Path where to look for httpd.conf (without filename). * flag Type of the parse request. */ -/* flag */ -#define FIRST_PARSE 0 -#define SUBDIR_PARSE 1 -#define SIGNALED_PARSE 2 -#define FIND_FROM_HTTPD_ROOT 3 +/* flag param: */ +enum { + FIRST_PARSE = 0, /* path will be "/etc" */ + SIGNALED_PARSE = 1, /* path will be "/etc" */ + SUBDIR_PARSE = 2, /* path will be derived from URL */ +}; static void parse_conf(const char *path, int flag) { + /* internally used extra flag state */ + enum { TRY_CURDIR_PARSE = 3 }; + FILE *f; -#if ENABLE_FEATURE_HTTPD_BASIC_AUTH - Htaccess *prev; -#endif - Htaccess *cur; - const char *filename = configFile; + const char *filename; char buf[160]; - char *p, *p0; - char *after_colon; - Htaccess_IP *pip; /* discard old rules */ free_Htaccess_IP_list(&ip_a_d); flg_deny_all = 0; /* retain previous auth and mime config only for subdir parse */ if (flag != SUBDIR_PARSE) { + free_Htaccess_list(&mime_a); #if ENABLE_FEATURE_HTTPD_BASIC_AUTH free_Htaccess_list(&g_auth); #endif - free_Htaccess_list(&mime_a); #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR free_Htaccess_list(&script_i); #endif } + filename = opt_c_configFile; if (flag == SUBDIR_PARSE || filename == NULL) { - filename = alloca(strlen(path) + sizeof(httpd_conf) + 2); - sprintf((char *)filename, "%s/%s", path, httpd_conf); + filename = alloca(strlen(path) + sizeof(HTTPD_CONF) + 2); + sprintf((char *)filename, "%s/%s", path, HTTPD_CONF); } while ((f = fopen_for_read(filename)) == NULL) { - if (flag == SUBDIR_PARSE || flag == FIND_FROM_HTTPD_ROOT) { + if (flag >= SUBDIR_PARSE) { /* SUBDIR or TRY_CURDIR */ /* config file not found, no changes to config */ return; } - if (configFile && flag == FIRST_PARSE) /* if -c option given */ - bb_simple_perror_msg_and_die(filename); - flag = FIND_FROM_HTTPD_ROOT; - filename = httpd_conf; + if (flag == FIRST_PARSE) { + /* -c CONFFILE given, but CONFFILE doesn't exist? */ + if (opt_c_configFile) + bb_simple_perror_msg_and_die(opt_c_configFile); + /* else: no -c, thus we looked at /etc/httpd.conf, + * and it's not there. try ./httpd.conf: */ + } + flag = TRY_CURDIR_PARSE; + filename = HTTPD_CONF; } #if ENABLE_FEATURE_HTTPD_BASIC_AUTH - prev = g_auth; -#endif - /* This could stand some work */ - while ((p0 = fgets(buf, sizeof(buf), f)) != NULL) { - after_colon = NULL; - for (p = p0; *p0 != '\0' && *p0 != '#'; p0++) { - if (!isspace(*p0)) { - *p++ = *p0; - if (*p0 == ':' && after_colon == NULL) - after_colon = p; + /* in "/file:user:pass" lines, we prepend path in subdirs */ + if (flag != SUBDIR_PARSE) + path = ""; +#endif + /* The lines can be: + * + * I:default_index_file + * H:http_home + * [AD]:IP[/mask] # allow/deny, * for wildcard + * Ennn:error.html # error page for status nnn + * P:/url:[http://]hostname[:port]/new/path # reverse proxy + * .ext:mime/type # mime type + * *.php:/path/php # run xxx.php through an interpreter + * /file:user:pass # username and password + */ + while (fgets(buf, sizeof(buf), f) != NULL) { + unsigned strlen_buf; + unsigned char ch; + char *after_colon = NULL; + + { /* remove all whitespace, and # comments */ + char *p, *p0; + + p = p0 = buf; + while ((ch = *p0++) != '\0' && ch != '#') { + if (!isspace(ch)) { + *p++ = ch; + if (ch == ':' && after_colon == NULL) + after_colon = p; + } } + *p = '\0'; + strlen_buf = p - buf; } - *p = '\0'; - /* test for empty or strange line */ + /* empty or strange line? */ if (after_colon == NULL || *after_colon == '\0') + goto config_error; + + ch = (buf[0] & ~0x20); /* toupper if it's a letter */ + + if (ch == 'I') { + index_page = xstrdup(after_colon); continue; - p0 = buf; - if (*p0 == 'd' || *p0 == 'a') - *p0 -= 0x20; /* a/d -> A/D */ - if (*after_colon == '*') { - if (*p0 == 'D') { - /* memorize "deny all" */ - flg_deny_all = 1; - } - /* skip assumed "A:*", it is a default anyway */ + } + + /* do not allow jumping around using H in subdir's configs */ + if (flag == FIRST_PARSE && ch == 'H') { + home_httpd = xstrdup(after_colon); + xchdir(home_httpd); continue; } - if (*p0 == 'A' || *p0 == 'D') { - /* storing current config IP line */ - pip = xzalloc(sizeof(Htaccess_IP)); - if (scan_ip_mask(after_colon, &(pip->ip), &(pip->mask))) { + if (ch == 'A' || ch == 'D') { + Htaccess_IP *pip; + + if (*after_colon == '*') { + if (ch == 'D') { + /* memorize "deny all" */ + flg_deny_all = 1; + } + /* skip assumed "A:*", it is a default anyway */ + continue; + } + /* store "allow/deny IP/mask" line */ + pip = xzalloc(sizeof(*pip)); + if (scan_ip_mask(after_colon, &pip->ip, &pip->mask)) { /* IP{/mask} syntax error detected, protect all */ - *p0 = 'D'; + ch = 'D'; pip->mask = 0; } - pip->allow_deny = *p0; - if (*p0 == 'D') { + pip->allow_deny = ch; + if (ch == 'D') { /* Deny:from_IP - prepend */ pip->next = ip_a_d; ip_a_d = pip; } else { - /* A:from_IP - append (thus D precedes A) */ + /* A:from_IP - append (thus all D's precedes A's) */ Htaccess_IP *prev_IP = ip_a_d; if (prev_IP == NULL) { ip_a_d = pip; @@ -575,12 +604,12 @@ static void parse_conf(const char *path, int flag) } #if ENABLE_FEATURE_HTTPD_ERROR_PAGES - if (flag == FIRST_PARSE && *p0 == 'E') { + if (flag == FIRST_PARSE && ch == 'E') { unsigned i; - int status = atoi(++p0); /* error status code */ + int status = atoi(buf + 1); /* error status code */ + if (status < HTTP_CONTINUE) { - bb_error_msg("config error '%s' in '%s'", buf, filename); - continue; + goto config_error; } /* then error page; find matching status */ for (i = 0; i < ARRAY_SIZE(http_response_type); i++) { @@ -597,7 +626,7 @@ static void parse_conf(const char *path, int flag) #endif #if ENABLE_FEATURE_HTTPD_PROXY - if (flag == FIRST_PARSE && *p0 == 'P') { + if (flag == FIRST_PARSE && ch == 'P') { /* P:/url:[http://]hostname[:port]/new/path */ char *url_from, *host_port, *url_to; Htaccess_Proxy *proxy_entry; @@ -605,23 +634,20 @@ static void parse_conf(const char *path, int flag) url_from = after_colon; host_port = strchr(after_colon, ':'); if (host_port == NULL) { - bb_error_msg("config error '%s' in '%s'", buf, filename); - continue; + goto config_error; } *host_port++ = '\0'; if (strncmp(host_port, "http://", 7) == 0) host_port += 7; if (*host_port == '\0') { - bb_error_msg("config error '%s' in '%s'", buf, filename); - continue; + goto config_error; } url_to = strchr(host_port, '/'); if (url_to == NULL) { - bb_error_msg("config error '%s' in '%s'", buf, filename); - continue; + goto config_error; } *url_to = '\0'; - proxy_entry = xzalloc(sizeof(Htaccess_Proxy)); + proxy_entry = xzalloc(sizeof(*proxy_entry)); proxy_entry->url_from = xstrdup(url_from); proxy_entry->host_port = xstrdup(host_port); *url_to = '/'; @@ -631,115 +657,87 @@ static void parse_conf(const char *path, int flag) continue; } #endif + /* the rest of directives are non-alphabetic, + * must avoid using "toupper'ed" ch */ + ch = buf[0]; -#if ENABLE_FEATURE_HTTPD_BASIC_AUTH - if (*p0 == '/') { - /* make full path from httpd root / current_path / config_line_path */ - const char *tp = (flag == SUBDIR_PARSE ? path : ""); - p0 = xmalloc(strlen(tp) + (after_colon - buf) + 2 + strlen(after_colon)); - after_colon[-1] = '\0'; - sprintf(p0, "/%s%s", tp, buf); - - /* looks like bb_simplify_path... */ - tp = p = p0; - do { - if (*p == '/') { - if (*tp == '/') { /* skip duplicate (or initial) slash */ - continue; - } - if (*tp == '.') { - if (tp[1] == '/' || tp[1] == '\0') { /* remove extra '.' */ - continue; - } - if ((tp[1] == '.') && (tp[2] == '/' || tp[2] == '\0')) { - ++tp; - if (p > p0) { - while (*--p != '/') /* omit previous dir */ - continue; - } - continue; - } - } - } - *++p = *tp; - } while (*++tp); + if (ch == '.' /* ".ext:mime/type" */ +#if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR + || (ch == '*' && buf[1] == '.') /* "*.php:/path/php" */ +#endif + ) { + char *p; + Htaccess *cur; - if ((p == p0) || (*p != '/')) { /* not a trailing slash */ - ++p; /* so keep last character */ + cur = xzalloc(sizeof(*cur) /* includes space for NUL */ + strlen_buf); + strcpy(cur->before_colon, buf); + p = cur->before_colon + (after_colon - buf); + p[-1] = '\0'; + cur->after_colon = p; + if (ch == '.') { + /* .mime line: prepend to mime_a list */ + cur->next = mime_a; + mime_a = cur; + } +#if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR + else { + /* script interpreter line: prepend to script_i list */ + cur->next = script_i; + script_i = cur; } - *p = ':'; - strcpy(p + 1, after_colon); - } #endif - if (*p0 == 'I') { - index_page = xstrdup(after_colon); - continue; - } - - /* Do not allow jumping around using H in subdir's configs */ - if (flag == FIRST_PARSE && *p0 == 'H') { - home_httpd = xstrdup(after_colon); - xchdir(home_httpd); continue; } - /* storing current config line */ - cur = xzalloc(sizeof(Htaccess) + strlen(p0)); - strcpy(cur->before_colon, p0); #if ENABLE_FEATURE_HTTPD_BASIC_AUTH - if (*p0 == '/') /* was malloced - see above */ - free(p0); -#endif - cur->after_colon = strchr(cur->before_colon, ':'); - *cur->after_colon++ = '\0'; - if (cur->before_colon[0] == '.') { - /* .mime line: prepend to mime_a list */ - cur->next = mime_a; - mime_a = cur; - continue; - } -#if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR - if (cur->before_colon[0] == '*' && cur->before_colon[1] == '.') { - /* script interpreter line: prepend to script_i list */ - cur->next = script_i; - script_i = cur; - continue; - } -#endif -#if ENABLE_FEATURE_HTTPD_BASIC_AUTH -//TODO: we do not test for leading "/"?? -//also, do we leak cur if BASIC_AUTH is off? - if (prev == NULL) { - /* first line */ - g_auth = prev = cur; - } else { - /* sort path, if current length eq or bigger then move up */ - Htaccess *prev_hti = g_auth; - size_t l = strlen(cur->before_colon); - Htaccess *hti; - - for (hti = prev_hti; hti; hti = hti->next) { - if (l >= strlen(hti->before_colon)) { - /* insert before hti */ - cur->next = hti; - if (prev_hti != hti) { - prev_hti->next = cur; - } else { - /* insert as top */ - g_auth = cur; + if (ch == '/') { /* "/file:user:pass" */ + char *p; + Htaccess *cur; + unsigned file_len; + + /* note: path is "" unless we are in SUBDIR parse, + * otherwise it always starts with "/" */ + cur = xzalloc(sizeof(*cur) /* includes space for NUL */ + + strlen(path) + + strlen_buf + ); + /* form "/path/file" */ + sprintf(cur->before_colon, "%s%.*s", + path, + after_colon - buf - 1, /* includes "/", but not ":" */ + buf); + /* canonicalize it */ + p = bb_simplify_abs_path_inplace(cur->before_colon); + file_len = p - cur->before_colon; + /* add "user:pass" after NUL */ + strcpy(++p, after_colon); + cur->after_colon = p; + + /* insert cur into g_auth */ + /* g_auth is sorted by decreased filename length */ + { + Htaccess *auth, **authp; + + authp = &g_auth; + while ((auth = *authp) != NULL) { + if (file_len >= strlen(auth->before_colon)) { + /* insert cur before auth */ + cur->next = auth; + break; } - break; + authp = &auth->next; } - if (prev_hti != hti) - prev_hti = prev_hti->next; - } - if (!hti) { /* not inserted, add to bottom */ - prev->next = cur; - prev = cur; + *authp = cur; } + continue; } #endif /* BASIC_AUTH */ + + /* the line is not recognized */ + config_error: + bb_error_msg("config error '%s' in '%s'", buf, filename); } /* while (fgets) */ + fclose(f); } @@ -2031,8 +2029,8 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr) /* We are done reading headers, disable peer timeout */ alarm(0); - if (strcmp(bb_basename(urlcopy), httpd_conf) == 0 || !ip_allowed) { - /* protect listing [/path]/httpd_conf or IP deny */ + if (strcmp(bb_basename(urlcopy), HTTPD_CONF) == 0 || !ip_allowed) { + /* protect listing [/path]/httpd.conf or IP deny */ send_headers_and_exit(HTTP_FORBIDDEN); } @@ -2245,7 +2243,7 @@ static void mini_httpd_inetd(void) static void sighup_handler(int sig UNUSED_PARAM) { - parse_conf(default_path_httpd_conf, SIGNALED_PARSE); + parse_conf(DEFAULT_PATH_HTTPD_CONF, SIGNALED_PARSE); } enum { @@ -2304,7 +2302,7 @@ int httpd_main(int argc UNUSED_PARAM, char **argv) IF_FEATURE_HTTPD_AUTH_MD5("m:") IF_FEATURE_HTTPD_SETUID("u:") "p:ifv", - &configFile, &url_for_decode, &home_httpd + &opt_c_configFile, &url_for_decode, &home_httpd IF_FEATURE_HTTPD_ENCODE_URL_STR(, &url_for_encode) IF_FEATURE_HTTPD_BASIC_AUTH(, &g_realm) IF_FEATURE_HTTPD_AUTH_MD5(, &pass) @@ -2375,7 +2373,7 @@ int httpd_main(int argc UNUSED_PARAM, char **argv) } #endif - parse_conf(default_path_httpd_conf, FIRST_PARSE); + parse_conf(DEFAULT_PATH_HTTPD_CONF, FIRST_PARSE); if (!(opt & OPT_INETD)) signal(SIGHUP, sighup_handler);