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
This commit is contained in:
Denis Vlasenko 2009-04-22 13:49:16 +00:00
parent 574c316e5a
commit 1cf4a0eb81
3 changed files with 200 additions and 194 deletions

View File

@ -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;

View File

@ -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;
return start;
*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);
}
bb_simplify_abs_path_inplace(s);
return s;
}

View File

@ -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;
/* in "/file:user:pass" lines, we prepend path in subdirs */
if (flag != SUBDIR_PARSE)
path = "";
#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;
}
}
*p = '\0';
/* 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;
/* test for empty or strange line */
{ /* 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;
}
/* empty or strange line? */
if (after_colon == NULL || *after_colon == '\0')
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 */
goto config_error;
ch = (buf[0] & ~0x20); /* toupper if it's a letter */
if (ch == 'I') {
index_page = xstrdup(after_colon);
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))) {
/* 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 (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 ((p == p0) || (*p != '/')) { /* not a trailing slash */
++p; /* so keep last character */
}
*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 (ch == '.' /* ".ext:mime/type" */
#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;
|| (ch == '*' && buf[1] == '.') /* "*.php:/path/php" */
#endif
) {
char *p;
Htaccess *cur;
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;
}
#endif
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 ENABLE_FEATURE_HTTPD_BASIC_AUTH
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);