busybox/networking/httpd.c
Denys Vlasenko 70683faf38 httpd: don't send Content-Length in error pages header
function                                             old     new   delta
send_headers                                         701     713     +12

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-12-17 20:37:58 +01:00

2903 lines
82 KiB
C

/* vi: set sw=4 ts=4: */
/*
* httpd implementation for busybox
*
* Copyright (C) 2002,2003 Glenn Engel <glenne@engel.org>
* Copyright (C) 2003-2006 Vladimir Oleynik <dzo@simtreas.ru>
*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*
*****************************************************************************
*
* Typical usage:
* For non root user:
* httpd -p 8080 -h $HOME/public_html
* For daemon start from rc script with uid=0:
* httpd -u www
* which is equivalent to (assuming user www has uid 80):
* httpd -p 80 -u 80 -h $PWD -c /etc/httpd.conf -r "Web Server Authentication"
*
* When an url starts with "/cgi-bin/" it is assumed to be a cgi script.
* The server changes directory to the location of the script and executes it
* after setting QUERY_STRING and other environment variables.
*
* If directory URL is given, no index.html is found and CGI support is enabled,
* cgi-bin/index.cgi will be run. Directory to list is ../$QUERY_STRING.
* See httpd_indexcgi.c for an example GCI code.
*
* Doc:
* "CGI Environment Variables": http://hoohoo.ncsa.uiuc.edu/cgi/env.html
*
* The applet can also be invoked as an url arg decoder and html text encoder
* as follows:
* foo=`httpd -d $foo` # decode "Hello%20World" as "Hello World"
* bar=`httpd -e "<Hello World>"` # encode as "&#60Hello&#32World&#62"
* Note that url encoding for arguments is not the same as html encoding for
* presentation. -d decodes an url-encoded argument while -e encodes in html
* for page display.
*
* httpd.conf has the following format:
*
* H:/serverroot # define the server root. It will override -h
* A:172.20. # Allow address from 172.20.0.0/16
* A:10.0.0.0/25 # Allow any address from 10.0.0.0-10.0.0.127
* A:10.0.0.0/255.255.255.128 # Allow any address that previous set
* A:127.0.0.1 # Allow local loopback connections
* D:* # Deny from other IP connections
* E404:/path/e404.html # /path/e404.html is the 404 (not found) error page
* I:index.html # Show index.html when a directory is requested
*
* P:/url:[http://]hostname[:port]/new/path
* # When /urlXXXXXX is requested, reverse proxy
* # it to http://hostname[:port]/new/pathXXXXXX
*
* /cgi-bin:foo:bar # Require user foo, pwd bar on urls starting with /cgi-bin/
* /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/
* /adm:root:* # or user root, pwd from /etc/passwd on urls starting with /adm/
* /wiki:*:* # or any user from /etc/passwd with according pwd on urls starting with /wiki/
* .au:audio/basic # additional mime type for audio.au files
* *.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:
* - Default is to allow all (Allow all (A:*) is a no-op).
* - Deny rules take precedence over allow rules.
* - "Deny all" rule (D:*) is applied last.
*
* Example:
* 1. Allow only specified addresses
* A:172.20 # Allow any address that begins with 172.20.
* A:10.10. # Allow any address that begins with 10.10.
* A:127.0.0.1 # Allow local loopback connections
* D:* # Deny from other IP connections
*
* 2. Only deny specified addresses
* D:1.2.3. # deny from 1.2.3.0 - 1.2.3.255
* D:2.3.4. # deny from 2.3.4.0 - 2.3.4.255
* A:* # (optional line added for clarity)
*
* If a sub directory contains config file, it is parsed and merged with
* any existing settings as if it was appended to the original configuration.
*
* subdir paths are relative to the containing subdir and thus cannot
* affect the parent rules.
*
* Note that since the sub dir is parsed in the forked thread servicing the
* subdir http request, any merge is discarded when the process exits. As a
* result, the subdir settings only have a lifetime of a single request.
*
* Custom error pages can contain an absolute path or be relative to
* 'home_httpd'. Error pages are to be static files (no CGI or script). Error
* page can only be defined in the root configuration file and are not taken
* into account in local (directories) config files.
*
* If -c is not set, an attempt will be made to open the default
* root configuration file. If -c is set and the file is not found, the
* server exits with an error.
*/
//config:config HTTPD
//config: bool "httpd (32 kb)"
//config: default y
//config: help
//config: HTTP server.
//config:
//config:config FEATURE_HTTPD_PORT_DEFAULT
//config: int "Default port"
//config: default 80
//config: range 1 65535
//config: depends on HTTPD
//config:
//config:config FEATURE_HTTPD_RANGES
//config: bool "Support 'Ranges:' header"
//config: default y
//config: depends on HTTPD
//config: help
//config: Makes httpd emit "Accept-Ranges: bytes" header and understand
//config: "Range: bytes=NNN-[MMM]" header. Allows for resuming interrupted
//config: downloads, seeking in multimedia players etc.
//config:
//config:config FEATURE_HTTPD_SETUID
//config: bool "Enable -u <user> option"
//config: default y
//config: depends on HTTPD
//config: help
//config: This option allows the server to run as a specific user
//config: rather than defaulting to the user that starts the server.
//config: Use of this option requires special privileges to change to a
//config: different user.
//config:
//config:config FEATURE_HTTPD_BASIC_AUTH
//config: bool "Enable HTTP authentication"
//config: default y
//config: depends on HTTPD
//config: help
//config: Utilizes password settings from /etc/httpd.conf for basic
//config: authentication on a per url basis.
//config: Example for httpd.conf file:
//config: /adm:toor:PaSsWd
//config:
//config:config FEATURE_HTTPD_AUTH_MD5
//config: bool "Support MD5-encrypted passwords in HTTP authentication"
//config: default y
//config: depends on FEATURE_HTTPD_BASIC_AUTH
//config: help
//config: Enables encrypted passwords, and wildcard user/passwords
//config: in httpd.conf file.
//config: User '*' means 'any system user name is ok',
//config: password of '*' means 'use system password for this user'
//config: Examples:
//config: /adm:toor:$1$P/eKnWXS$aI1aPGxT.dJD5SzqAKWrF0
//config: /adm:root:*
//config: /wiki:*:*
//config:
//config:config FEATURE_HTTPD_CGI
//config: bool "Support Common Gateway Interface (CGI)"
//config: default y
//config: depends on HTTPD
//config: help
//config: This option allows scripts and executables to be invoked
//config: when specific URLs are requested.
//config:
//config:config FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
//config: bool "Support running scripts through an interpreter"
//config: default y
//config: depends on FEATURE_HTTPD_CGI
//config: help
//config: This option enables support for running scripts through an
//config: interpreter. Turn this on if you want PHP scripts to work
//config: properly. You need to supply an additional line in your
//config: httpd.conf file:
//config: *.php:/path/to/your/php
//config:
//config:config FEATURE_HTTPD_SET_REMOTE_PORT_TO_ENV
//config: bool "Set REMOTE_PORT environment variable for CGI"
//config: default y
//config: depends on FEATURE_HTTPD_CGI
//config: help
//config: Use of this option can assist scripts in generating
//config: references that contain a unique port number.
//config:
//config:config FEATURE_HTTPD_ENCODE_URL_STR
//config: bool "Enable -e option (useful for CGIs written as shell scripts)"
//config: default y
//config: depends on HTTPD
//config: help
//config: This option allows html encoding of arbitrary strings for display
//config: by the browser. Output goes to stdout.
//config: For example, httpd -e "<Hello World>" produces
//config: "&#60Hello&#32World&#62".
//config:
//config:config FEATURE_HTTPD_ERROR_PAGES
//config: bool "Support custom error pages"
//config: default y
//config: depends on HTTPD
//config: help
//config: This option allows you to define custom error pages in
//config: the configuration file instead of the default HTTP status
//config: error pages. For instance, if you add the line:
//config: E404:/path/e404.html
//config: in the config file, the server will respond the specified
//config: '/path/e404.html' file instead of the terse '404 NOT FOUND'
//config: message.
//config:
//config:config FEATURE_HTTPD_PROXY
//config: bool "Support reverse proxy"
//config: default y
//config: depends on HTTPD
//config: help
//config: This option allows you to define URLs that will be forwarded
//config: to another HTTP server. To setup add the following line to the
//config: configuration file
//config: P:/url/:http://hostname[:port]/new/path/
//config: Then a request to /url/myfile will be forwarded to
//config: http://hostname[:port]/new/path/myfile.
//config:
//config:config FEATURE_HTTPD_GZIP
//config: bool "Support GZIP content encoding"
//config: default y
//config: depends on HTTPD
//config: help
//config: Makes httpd send files using GZIP content encoding if the
//config: client supports it and a pre-compressed <file>.gz exists.
//config:
//config:config FEATURE_HTTPD_ETAG
//config: bool "Support caching via ETag header"
//config: default y
//config: depends on HTTPD
//config: help
//config: If server responds with ETag then next time client (browser)
//config: resend it via If-None-Match header.
//config: Then httpd will check if file wasn't modified and if not,
//config: return 304 Not Modified status code.
//config: The ETag value is constructed from last modification date
//config: in unix epoch, and size: "hex(last_mod)-hex(file_size)".
//config: It's not completely reliable as hash functions but fair enough.
//config:
//config:config FEATURE_HTTPD_LAST_MODIFIED
//config: bool "Add Last-Modified header to response"
//config: default y
//config: depends on HTTPD
//config: help
//config: The Last-Modified header is used for cache validation.
//config: The client sends last seen mtime to server in If-Modified-Since.
//config: Both headers MUST be an RFC 1123 formatted, which is hard to parse.
//config: Use ETag header instead.
//config:
//config:config FEATURE_HTTPD_DATE
//config: bool "Add Date header to response"
//config: default y
//config: depends on HTTPD
//config: help
//config: RFC2616 says that server MUST add Date header to response.
//config: But it is almost useless and can be omitted.
//config:
//config:config FEATURE_HTTPD_ACL_IP
//config: bool "ACL IP"
//config: default y
//config: depends on HTTPD
//config: help
//config: Support IP deny/allow rules
//applet:IF_HTTPD(APPLET(httpd, BB_DIR_USR_SBIN, BB_SUID_DROP))
//kbuild:lib-$(CONFIG_HTTPD) += httpd.o
//usage:#define httpd_trivial_usage
//usage: "[-ifv[v]]"
//usage: " [-c CONFFILE]"
//usage: " [-p [IP:]PORT]"
//usage: IF_FEATURE_HTTPD_SETUID(" [-u USER[:GRP]]")
//usage: IF_FEATURE_HTTPD_BASIC_AUTH(" [-r REALM]")
//usage: " [-h HOME]\n"
//usage: "or httpd -d/-e" IF_FEATURE_HTTPD_AUTH_MD5("/-m") " STRING"
//usage:#define httpd_full_usage "\n\n"
//usage: "Listen for incoming HTTP requests\n"
//usage: "\n -i Inetd mode"
//usage: "\n -f Run in foreground"
//usage: "\n -v[v] Verbose"
//usage: "\n -p [IP:]PORT Bind to IP:PORT (default *:"STR(CONFIG_FEATURE_HTTPD_PORT_DEFAULT)")"
//usage: IF_FEATURE_HTTPD_SETUID(
//usage: "\n -u USER[:GRP] Set uid/gid after binding to port")
//usage: IF_FEATURE_HTTPD_BASIC_AUTH(
//usage: "\n -r REALM Authentication Realm for Basic Authentication")
//usage: "\n -h HOME Home directory (default .)"
//usage: "\n -c FILE Configuration file (default {/etc,HOME}/httpd.conf)"
//usage: IF_FEATURE_HTTPD_AUTH_MD5(
//usage: "\n -m STRING MD5 crypt STRING")
//usage: "\n -e STRING HTML encode STRING"
//usage: "\n -d STRING URL decode STRING"
/* TODO: use TCP_CORK, parse_config() */
#include "libbb.h"
#include "common_bufsiz.h"
#if ENABLE_PAM
/* PAM may include <locale.h>. We may need to undefine bbox's stub define: */
# undef setlocale
/* For some obscure reason, PAM is not in pam/xxx, but in security/xxx.
* Apparently they like to confuse people. */
# include <security/pam_appl.h>
# include <security/pam_misc.h>
#endif
#if ENABLE_FEATURE_USE_SENDFILE
# include <sys/sendfile.h>
#endif
/* see sys/netinet6/in6.h */
#if defined(__FreeBSD__)
# define s6_addr32 __u6_addr.__u6_addr32
#endif
#define DEBUG 0
#if DEBUG
# define dbg(...) fprintf(stderr, __VA_ARGS__)
#else
# define dbg(...) ((void)0)
#endif
#define IOBUF_SIZE 8192
#define MAX_HTTP_HEADERS_SIZE (32*1024)
#define HEADER_READ_TIMEOUT 60
#define STR1(s) #s
#define STR(s) STR1(s)
static const char DEFAULT_PATH_HTTPD_CONF[] ALIGN1 = "/etc";
static const char HTTPD_CONF[] ALIGN1 = "httpd.conf";
static const char HTTP_200[] ALIGN1 = "HTTP/1.1 200 OK\r\n";
static const char index_html[] ALIGN1 = "index.html";
typedef struct has_next_ptr {
struct has_next_ptr *next;
} has_next_ptr;
/* Must have "next" as a first member */
typedef struct Htaccess {
struct Htaccess *next;
char *after_colon;
char before_colon[1]; /* really bigger, must be last */
} Htaccess;
#if ENABLE_FEATURE_HTTPD_ACL_IP
/* Must have "next" as a first member */
typedef struct Htaccess_IP {
struct Htaccess_IP *next;
unsigned ip;
unsigned mask;
int allow_deny;
} Htaccess_IP;
#endif
/* Must have "next" as a first member */
typedef struct Htaccess_Proxy {
struct Htaccess_Proxy *next;
char *url_from;
char *host_port;
char *url_to;
} Htaccess_Proxy;
enum {
HTTP_OK = 200,
HTTP_PARTIAL_CONTENT = 206,
HTTP_MOVED_TEMPORARILY = 302,
HTTP_NOT_MODIFIED = 304,
HTTP_BAD_REQUEST = 400, /* malformed syntax */
HTTP_UNAUTHORIZED = 401, /* authentication needed, respond with auth hdr */
HTTP_NOT_FOUND = 404,
HTTP_FORBIDDEN = 403,
HTTP_REQUEST_TIMEOUT = 408,
HTTP_NOT_IMPLEMENTED = 501, /* used for unrecognized requests */
HTTP_INTERNAL_SERVER_ERROR = 500,
HTTP_ENTITY_TOO_LARGE = 413,
HTTP_CONTINUE = 100,
#if 0 /* future use */
HTTP_SWITCHING_PROTOCOLS = 101,
HTTP_CREATED = 201,
HTTP_ACCEPTED = 202,
HTTP_NON_AUTHORITATIVE_INFO = 203,
HTTP_NO_CONTENT = 204,
HTTP_MULTIPLE_CHOICES = 300,
HTTP_MOVED_PERMANENTLY = 301,
HTTP_PAYMENT_REQUIRED = 402,
HTTP_BAD_GATEWAY = 502,
HTTP_SERVICE_UNAVAILABLE = 503, /* overload, maintenance */
#endif
};
static const uint16_t http_response_type[] ALIGN2 = {
HTTP_OK,
#if ENABLE_FEATURE_HTTPD_RANGES
HTTP_PARTIAL_CONTENT,
#endif
HTTP_MOVED_TEMPORARILY,
#if ENABLE_FEATURE_HTTPD_ETAG
HTTP_NOT_MODIFIED,
#endif
HTTP_REQUEST_TIMEOUT,
HTTP_NOT_IMPLEMENTED,
#if ENABLE_FEATURE_HTTPD_BASIC_AUTH
HTTP_UNAUTHORIZED,
#endif
HTTP_NOT_FOUND,
HTTP_BAD_REQUEST,
HTTP_FORBIDDEN,
HTTP_INTERNAL_SERVER_ERROR,
HTTP_ENTITY_TOO_LARGE,
#if 0 /* not implemented */
HTTP_CREATED,
HTTP_ACCEPTED,
HTTP_NO_CONTENT,
HTTP_MULTIPLE_CHOICES,
HTTP_MOVED_PERMANENTLY,
HTTP_BAD_GATEWAY,
HTTP_SERVICE_UNAVAILABLE,
#endif
};
static const struct {
const char *name;
const char *info;
} http_response[ARRAY_SIZE(http_response_type)] = {
{ "OK", NULL },
#if ENABLE_FEATURE_HTTPD_RANGES
{ "Partial Content", NULL },
#endif
{ "Found", NULL },
#if ENABLE_FEATURE_HTTPD_ETAG
{ "Not Modified" },
#endif
{ "Request Timeout", "No request appeared within 60 seconds" },
{ "Not Implemented", "The requested method is not recognized" },
#if ENABLE_FEATURE_HTTPD_BASIC_AUTH
{ "Unauthorized", "" },
#endif
{ "Not Found", "The requested URL was not found" },
{ "Bad Request", "Unsupported method" },
{ "Forbidden", "" },
{ "Internal Server Error", "Internal Server Error" },
{ "Entity Too Large", "Entity Too Large" },
#if 0 /* not implemented */
{ "Created" },
{ "Accepted" },
{ "No Content" },
{ "Multiple Choices" },
{ "Moved Permanently" },
{ "Bad Gateway", "" },
{ "Service Unavailable", "" },
#endif
};
struct globals {
int verbose; /* must be int (used by getopt32) */
smallint flg_deny_all;
#if ENABLE_FEATURE_HTTPD_GZIP
/* client can handle gzip / we are going to send gzip */
smallint content_gzip;
#endif
time_t last_mod;
#if ENABLE_FEATURE_HTTPD_ETAG
char *if_none_match;
#endif
char *rmt_ip_str; /* for $REMOTE_ADDR and $REMOTE_PORT */
const char *bind_addr_or_port;
char *g_query;
const char *opt_c_configFile;
const char *home_httpd;
const char *index_page;
const char *found_mime_type;
const char *found_moved_temporarily;
#if ENABLE_FEATURE_HTTPD_ACL_IP
Htaccess_IP *ip_a_d; /* config allow/deny lines */
#endif
IF_FEATURE_HTTPD_BASIC_AUTH(const char *g_realm;)
IF_FEATURE_HTTPD_BASIC_AUTH(char *remoteuser;)
off_t file_size; /* -1 - unknown */
#if ENABLE_FEATURE_HTTPD_RANGES
off_t range_start;
off_t range_end;
off_t range_len;
#endif
#if ENABLE_FEATURE_HTTPD_BASIC_AUTH
Htaccess *g_auth; /* config user:password lines */
#endif
Htaccess *mime_a; /* config mime types */
#if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
Htaccess *script_i; /* config script interpreters */
#endif
char *iobuf; /* [IOBUF_SIZE] */
#define hdr_buf bb_common_bufsiz1
#define sizeof_hdr_buf COMMON_BUFSIZE
char *hdr_ptr;
int hdr_cnt;
#if ENABLE_FEATURE_HTTPD_ETAG
char etag[sizeof("'%llx-%llx'") + 2 * sizeof(long long)*3];
#endif
#if ENABLE_FEATURE_HTTPD_ERROR_PAGES
const char *http_error_page[ARRAY_SIZE(http_response_type)];
#endif
#if ENABLE_FEATURE_HTTPD_PROXY
Htaccess_Proxy *proxy;
#endif
};
#define G (*ptr_to_globals)
#define verbose (G.verbose )
#define flg_deny_all (G.flg_deny_all )
#if ENABLE_FEATURE_HTTPD_GZIP
# define content_gzip (G.content_gzip )
#else
# define content_gzip 0
#endif
#define bind_addr_or_port (G.bind_addr_or_port)
#define g_query (G.g_query )
#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 )
#define found_moved_temporarily (G.found_moved_temporarily)
#define last_mod (G.last_mod )
#define g_realm (G.g_realm )
#define remoteuser (G.remoteuser )
#define file_size (G.file_size )
#if ENABLE_FEATURE_HTTPD_RANGES
#define range_start (G.range_start )
#define range_end (G.range_end )
#define range_len (G.range_len )
#else
enum {
range_start = -1,
range_end = MAXINT(off_t) - 1,
range_len = MAXINT(off_t),
};
#endif
#define rmt_ip_str (G.rmt_ip_str )
#define g_auth (G.g_auth )
#define mime_a (G.mime_a )
#define script_i (G.script_i )
#define iobuf (G.iobuf )
#define hdr_ptr (G.hdr_ptr )
#define hdr_cnt (G.hdr_cnt )
#define http_error_page (G.http_error_page )
#define proxy (G.proxy )
#define INIT_G() do { \
setup_common_bufsiz(); \
SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
IF_FEATURE_HTTPD_BASIC_AUTH(g_realm = "Web Server Authentication";) \
IF_FEATURE_HTTPD_RANGES(range_start = -1;) \
bind_addr_or_port = STR(CONFIG_FEATURE_HTTPD_PORT_DEFAULT); \
index_page = index_html; \
file_size = -1; \
} while (0)
#define STRNCASECMP(a, str) strncasecmp((a), (str), sizeof(str)-1)
/* Prototypes */
enum {
SEND_HEADERS = (1 << 0),
SEND_BODY = (1 << 1),
};
static void send_file_and_exit(const char *url, int what) NORETURN;
static void free_llist(has_next_ptr **pptr)
{
has_next_ptr *cur = *pptr;
while (cur) {
has_next_ptr *t = cur;
cur = cur->next;
free(t);
}
*pptr = NULL;
}
static ALWAYS_INLINE void free_Htaccess_list(Htaccess **pptr)
{
free_llist((has_next_ptr**)pptr);
}
#if ENABLE_FEATURE_HTTPD_ACL_IP
static ALWAYS_INLINE void free_Htaccess_IP_list(Htaccess_IP **pptr)
{
free_llist((has_next_ptr**)pptr);
}
#endif
#if ENABLE_FEATURE_HTTPD_ACL_IP
/* Returns presumed mask width in bits or < 0 on error.
* Updates strp, stores IP at provided pointer */
static int scan_ip(const char **strp, unsigned *ipp, unsigned char endc)
{
const char *p = *strp;
int auto_mask = 8;
unsigned ip = 0;
int j;
if (*p == '/')
return -auto_mask;
for (j = 0; j < 4; j++) {
unsigned octet;
if ((*p < '0' || *p > '9') && *p != '/' && *p)
return -auto_mask;
octet = 0;
while (*p >= '0' && *p <= '9') {
octet *= 10;
octet += *p - '0';
if (octet > 255)
return -auto_mask;
p++;
}
if (*p == '.')
p++;
if (*p != '/' && *p)
auto_mask += 8;
ip = (ip << 8) | octet;
}
if (*p) {
if (*p != endc)
return -auto_mask;
p++;
if (*p == '\0')
return -auto_mask;
}
*ipp = ip;
*strp = p;
return auto_mask;
}
/* Returns 0 on success. Stores IP and mask at provided pointers */
static int scan_ip_mask(const char *str, unsigned *ipp, unsigned *maskp)
{
int i;
unsigned mask;
char *p;
i = scan_ip(&str, ipp, '/');
if (i < 0)
return i;
if (*str) {
/* there is /xxx after dotted-IP address */
i = bb_strtou(str, &p, 10);
if (*p == '.') {
/* 'xxx' itself is dotted-IP mask, parse it */
/* (return 0 (success) only if it has N.N.N.N form) */
return scan_ip(&str, maskp, '\0') - 32;
}
if (*p)
return -1;
}
if (i > 32)
return -1;
if (sizeof(unsigned) == 4 && i == 32) {
/* mask >>= 32 below may not work */
mask = 0;
} else {
mask = 0xffffffff;
mask >>= i;
}
/* i == 0 -> *maskp = 0x00000000
* i == 1 -> *maskp = 0x80000000
* i == 4 -> *maskp = 0xf0000000
* i == 31 -> *maskp = 0xfffffffe
* i == 32 -> *maskp = 0xffffffff */
*maskp = (uint32_t)(~mask);
return 0;
}
#endif
/*
* Parse configuration file into in-memory linked list.
*
* 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
* SUBDIR_PARSE.
* Error pages are only parsed on the main config file.
*
* path Path where to look for httpd.conf (without filename).
* flag Type of the parse request.
*/
/* 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 int parse_conf(const char *path, int flag)
{
/* internally used extra flag state */
enum { TRY_CURDIR_PARSE = 3 };
FILE *f;
const char *filename;
char buf[160];
/* discard old rules */
#if ENABLE_FEATURE_HTTPD_ACL_IP
free_Htaccess_IP_list(&G.ip_a_d);
#endif
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
#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);
}
while ((f = fopen_for_read(filename)) == NULL) {
if (flag >= SUBDIR_PARSE) { /* SUBDIR or TRY_CURDIR */
/* config file not found, no changes to config */
return -1;
}
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
/* 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;
{ /* remove all whitespace, and # comments */
char *p, *p0;
p0 = buf;
/* skip non-whitespace beginning. Often the whole line
* is non-whitespace. We want this case to work fast,
* without needless copying, therefore we don't merge
* this operation into next while loop. */
while ((ch = *p0) != '\0' && ch != '\n' && ch != '#'
&& ch != ' ' && ch != '\t'
) {
p0++;
}
p = p0;
/* if we enter this loop, we have some whitespace.
* discard it */
while (ch != '\0' && ch != '\n' && ch != '#') {
if (ch != ' ' && ch != '\t') {
*p++ = ch;
}
ch = *++p0;
}
*p = '\0';
strlen_buf = p - buf;
if (strlen_buf == 0)
continue; /* empty line */
}
after_colon = strchr(buf, ':');
/* 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') {
if (index_page != index_html)
free((char*)index_page);
index_page = xstrdup(after_colon);
continue;
}
/* 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 ENABLE_FEATURE_HTTPD_ACL_IP
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 */
ch = 'D';
pip->mask = 0;
}
pip->allow_deny = ch;
if (ch == 'D') {
/* Deny:from_IP - prepend */
pip->next = G.ip_a_d;
G.ip_a_d = pip;
} else {
/* A:from_IP - append (thus all D's precedes A's) */
Htaccess_IP *prev_IP = G.ip_a_d;
if (prev_IP == NULL) {
G.ip_a_d = pip;
} else {
while (prev_IP->next)
prev_IP = prev_IP->next;
prev_IP->next = pip;
}
}
continue;
}
#endif
#if ENABLE_FEATURE_HTTPD_ERROR_PAGES
if (flag == FIRST_PARSE && ch == 'E') {
unsigned i;
int status = atoi(buf + 1); /* error status code */
if (status < HTTP_CONTINUE) {
goto config_error;
}
/* then error page; find matching status */
for (i = 0; i < ARRAY_SIZE(http_response_type); i++) {
if (http_response_type[i] == status) {
/* We chdir to home_httpd, thus no need to
* concat_path_file(home_httpd, after_colon)
* here */
http_error_page[i] = xstrdup(after_colon);
break;
}
}
continue;
}
#endif
#if ENABLE_FEATURE_HTTPD_PROXY
if (flag == FIRST_PARSE && ch == 'P') {
/* P:/url:[http://]hostname[:port]/new/path */
char *url_from, *host_port, *url_to;
Htaccess_Proxy *proxy_entry;
url_from = after_colon;
host_port = strchr(after_colon, ':');
if (host_port == NULL) {
goto config_error;
}
*host_port++ = '\0';
if (is_prefixed_with(host_port, "http://"))
host_port += 7;
if (*host_port == '\0') {
goto config_error;
}
url_to = strchr(host_port, '/');
if (url_to == NULL) {
goto config_error;
}
*url_to = '\0';
proxy_entry = xzalloc(sizeof(*proxy_entry));
proxy_entry->url_from = xstrdup(url_from);
proxy_entry->host_port = xstrdup(host_port);
*url_to = '/';
proxy_entry->url_to = xstrdup(url_to);
proxy_entry->next = proxy;
proxy = proxy_entry;
continue;
}
#endif
/* the rest of directives are non-alphabetic,
* must avoid using "toupper'ed" ch */
ch = buf[0];
if (ch == '.' /* ".ext:mime/type" */
#if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
|| (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;
}
#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 does NOT start with "/" */
cur = xzalloc(sizeof(*cur) /* includes space for NUL */
+ 1 + strlen(path)
+ strlen_buf
);
/* form "/path/file" */
sprintf(cur->before_colon, "/%s%.*s",
path,
(int) (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;
}
authp = &auth->next;
}
*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);
return 0;
}
#if ENABLE_FEATURE_HTTPD_ENCODE_URL_STR
/*
* Given a string, html-encode special characters.
* This is used for the -e command line option to provide an easy way
* for scripts to encode result data without confusing browsers. The
* returned string pointer is memory allocated by malloc().
*
* Returns a pointer to the encoded string (malloced).
*/
static char *encodeString(const char *string)
{
/* take the simple route and encode everything */
/* could possibly scan once to get length. */
int len = strlen(string);
char *out = xmalloc(len * 6 + 1);
char *p = out;
char ch;
while ((ch = *string++) != '\0') {
/* very simple check for what to encode */
if (isalnum(ch))
*p++ = ch;
else
p += sprintf(p, "&#%u;", (unsigned char) ch);
}
*p = '\0';
return out;
}
#endif
#if ENABLE_FEATURE_HTTPD_BASIC_AUTH
/*
* Decode a base64 data stream as per rfc1521.
* Note that the rfc states that non base64 chars are to be ignored.
* Since the decode always results in a shorter size than the input,
* it is OK to pass the input arg as an output arg.
* Parameter: a pointer to a base64 encoded string.
* Decoded data is stored in-place.
*/
static void decodeBase64(char *data)
{
decode_base64(data, NULL)[0] = '\0';
}
#endif
/*
* Create a listen server socket on the designated port.
*/
static int openServer(void)
{
unsigned n = bb_strtou(bind_addr_or_port, NULL, 10);
if (!errno && n && n <= 0xffff)
n = create_and_bind_stream_or_die(NULL, n);
else
n = create_and_bind_stream_or_die(bind_addr_or_port, 80);
xlisten(n, 9);
return n;
}
/*
* Log the connection closure and exit.
*/
static void log_and_exit(void) NORETURN;
static void log_and_exit(void)
{
/* Paranoia. IE said to be buggy. It may send some extra data
* or be confused by us just exiting without SHUT_WR. Oh well. */
shutdown(1, SHUT_WR);
/* Why??
(this also messes up stdin when user runs httpd -i from terminal)
ndelay_on(0);
while (read(STDIN_FILENO, iobuf, IOBUF_SIZE) > 0)
continue;
*/
if (verbose > 2)
bb_simple_error_msg("closed");
_exit(xfunc_error_retval);
}
/*
* Create and send HTTP response headers.
* The arguments are combined and sent as one write operation. Note that
* IE will puke big-time if the headers are not sent in one packet and the
* second packet is delayed for any reason.
* responseNum - the result code to send.
*/
static void send_headers(unsigned responseNum)
{
#if ENABLE_FEATURE_HTTPD_DATE || ENABLE_FEATURE_HTTPD_LAST_MODIFIED
static const char RFC1123FMT[] ALIGN1 = "%a, %d %b %Y %H:%M:%S GMT";
/* Fixed size 29-byte string. Example: Sun, 06 Nov 1994 08:49:37 GMT */
char date_str[40]; /* using a bit larger buffer to paranoia reasons */
struct tm tm;
#endif
const char *responseString = "";
const char *infoString = NULL;
#if ENABLE_FEATURE_HTTPD_ERROR_PAGES
const char *error_page = NULL;
#endif
unsigned len;
unsigned i;
for (i = 0; i < ARRAY_SIZE(http_response_type); i++) {
if (http_response_type[i] == responseNum) {
responseString = http_response[i].name;
infoString = http_response[i].info;
#if ENABLE_FEATURE_HTTPD_ERROR_PAGES
error_page = http_error_page[i];
#endif
break;
}
}
if (verbose)
bb_error_msg("response:%u", responseNum);
/* We use sprintf, not snprintf (it's less code).
* iobuf[] is several kbytes long and all headers we generate
* always fit into those kbytes.
*/
{
#if ENABLE_FEATURE_HTTPD_DATE
time_t timer = time(NULL);
strftime(date_str, sizeof(date_str), RFC1123FMT, gmtime_r(&timer, &tm));
/* ^^^ using gmtime_r() instead of gmtime() to not use static data */
#endif
len = sprintf(iobuf,
"HTTP/1.1 %u %s\r\n"
#if ENABLE_FEATURE_HTTPD_DATE
"Date: %s\r\n"
#endif
"Connection: close\r\n",
responseNum, responseString
#if ENABLE_FEATURE_HTTPD_DATE
, date_str
#endif
);
}
if (responseNum != HTTP_OK || found_mime_type) {
len += sprintf(iobuf + len,
"Content-type: %s\r\n",
/* if it's error message, then it's HTML */
(responseNum != HTTP_OK ? "text/html" : found_mime_type)
);
}
#if ENABLE_FEATURE_HTTPD_BASIC_AUTH
if (responseNum == HTTP_UNAUTHORIZED) {
len += sprintf(iobuf + len,
"WWW-Authenticate: Basic realm=\"%.999s\"\r\n",
g_realm /* %.999s protects from overflowing iobuf[] */
);
}
#endif
if (responseNum == HTTP_MOVED_TEMPORARILY) {
/* Responding to "GET /dir" with
* "HTTP/1.1 302 Found" "Location: /dir/"
* - IOW, asking them to repeat with a slash.
* Here, overflow IS possible, can't use sprintf:
* mkdir test
* python -c 'print("get /test?" + ("x" * 8192))' | busybox httpd -i -h .
*/
len += snprintf(iobuf + len, IOBUF_SIZE-3 - len,
"Location: %s/%s%s\r\n",
found_moved_temporarily,
(g_query ? "?" : ""),
(g_query ? g_query : "")
);
if (len > IOBUF_SIZE-3)
len = IOBUF_SIZE-3;
}
#if ENABLE_FEATURE_HTTPD_ERROR_PAGES
if (error_page && access(error_page, R_OK) == 0) {
iobuf[len++] = '\r';
iobuf[len++] = '\n';
if (DEBUG) {
iobuf[len] = '\0';
fprintf(stderr, "headers: '%s'\n", iobuf);
}
full_write(STDOUT_FILENO, iobuf, len);
dbg("writing error page: '%s'\n", error_page);
return send_file_and_exit(error_page, SEND_BODY);
}
#endif
if (file_size != -1) { /* file */
#if ENABLE_FEATURE_HTTPD_LAST_MODIFIED
strftime(date_str, sizeof(date_str), RFC1123FMT, gmtime_r(&last_mod, &tm));
#endif
#if ENABLE_FEATURE_HTTPD_RANGES
if (responseNum == HTTP_PARTIAL_CONTENT) {
len += sprintf(iobuf + len,
"Content-Range: bytes %"OFF_FMT"u-%"OFF_FMT"u/%"OFF_FMT"u\r\n",
range_start,
range_end,
file_size
);
file_size = range_end - range_start + 1;
}
#endif
//RFC 2616 4.4 Message Length
// The transfer-length of a message is the length of the message-body as
// it appears in the message; that is, after any transfer-codings have
// been applied. When a message-body is included with a message, the
// transfer-length of that body is determined by one of the following
// (in order of precedence):
// 1.Any response message which "MUST NOT" include a message-body (such
// as the 1xx, 204, and 304 responses and any response to a HEAD
// request) is always terminated by the first empty line after the
// header fields, regardless of the entity-header fields present in
// the message.
// 2.If a Transfer-Encoding header field (section 14.41) is present and
// has any value other than "identity", then the transfer-length is
// defined by use of the "chunked" transfer-coding (section 3.6),
// unless the message is terminated by closing the connection.
// 3.If a Content-Length header field (section 14.13) is present, its
// decimal value in OCTETs represents both the entity-length and the
// transfer-length. The Content-Length header field MUST NOT be sent
// if these two lengths are different (i.e., if a Transfer-Encoding
// header field is present). If a message is received with both a
// Transfer-Encoding header field and a Content-Length header field,
// the latter MUST be ignored.
// 4.If the message uses the media type "multipart/byteranges" ...
// 5.By the server closing the connection.
//
// (NB: standards do not define "Transfer-Length:" _header_,
// transfer-length above is just a concept).
#if ENABLE_FEATURE_HTTPD_RANGES \
|| ENABLE_FEATURE_HTTPD_LAST_MODIFIED \
|| ENABLE_FEATURE_HTTPD_ETAG
len += sprintf(iobuf + len,
# if ENABLE_FEATURE_HTTPD_RANGES
"Accept-Ranges: bytes\r\n"
# endif
# if ENABLE_FEATURE_HTTPD_LAST_MODIFIED
"Last-Modified: %s\r\n"
# endif
# if ENABLE_FEATURE_HTTPD_ETAG
"ETag: %s\r\n"
# endif
# if ENABLE_FEATURE_HTTPD_LAST_MODIFIED
, date_str
# endif
# if ENABLE_FEATURE_HTTPD_ETAG
, G.etag
# endif
#endif
);
if (!infoString) {
len += sprintf(iobuf + len,
/* Because of 4.4 (5), we can forgo sending of "Content-Length"
* since we close connection afterwards, but it helps clients
* to e.g. estimate download times, show progress bars etc.
* Theoretically we should not send it if page is compressed,
* but de-facto standard is to send it (see comment below).
*/
"Content-Length: %"OFF_FMT"u\r\n",
file_size
);
}
}
/* This should be "Transfer-Encoding", not "Content-Encoding":
* "data is compressed for transfer", not "data is an archive".
* But many clients were not handling "Transfer-Encoding" correctly
* (they were not uncompressing gzipped pages, tried to show
* raw compressed data), and servers worked around it by using
* "Content-Encoding" instead... and this become de-facto standard.
* https://bugzilla.mozilla.org/show_bug.cgi?id=68517
* https://bugs.chromium.org/p/chromium/issues/detail?id=94730
*/
if (content_gzip)
len += sprintf(iobuf + len, "Content-Encoding: gzip\r\n");
iobuf[len++] = '\r';
iobuf[len++] = '\n';
if (infoString) {
len += sprintf(iobuf + len,
"<HTML><HEAD><TITLE>%u %s</TITLE></HEAD>\n"
"<BODY><H1>%u %s</H1>\n"
"%s\n"
"</BODY></HTML>\n",
responseNum, responseString,
responseNum, responseString,
infoString
);
}
if (DEBUG) {
iobuf[len] = '\0';
fprintf(stderr, "headers: '%s'\n", iobuf);
}
if (full_write(STDOUT_FILENO, iobuf, len) != len) {
if (verbose > 1)
bb_simple_perror_msg("error");
log_and_exit();
}
}
static void send_headers_and_exit(int responseNum) NORETURN;
static void send_headers_and_exit(int responseNum)
{
IF_FEATURE_HTTPD_GZIP(content_gzip = 0;)
send_headers(responseNum);
log_and_exit();
}
/*
* Read from the socket until '\n' or EOF.
* '\r' chars are removed.
* '\n' is replaced with NUL.
* Return number of characters read or 0 if nothing is read
* ('\r' and '\n' are not counted).
* Data is returned in iobuf.
*/
static unsigned get_line(void)
{
unsigned count;
char c;
count = 0;
while (1) {
if (hdr_cnt <= 0) {
alarm(HEADER_READ_TIMEOUT);
hdr_cnt = safe_read(STDIN_FILENO, hdr_buf, sizeof_hdr_buf);
if (hdr_cnt <= 0)
goto ret;
hdr_ptr = hdr_buf;
}
hdr_cnt--;
c = *hdr_ptr++;
if (c == '\r')
continue;
if (c == '\n')
break;
iobuf[count] = c;
if (count < (IOBUF_SIZE - 1)) /* check overflow */
count++;
}
ret:
iobuf[count] = '\0';
return count;
}
#if ENABLE_FEATURE_HTTPD_CGI || ENABLE_FEATURE_HTTPD_PROXY
/* gcc 4.2.1 fares better with NOINLINE */
static NOINLINE void cgi_io_loop_and_exit(int fromCgi_rd, int toCgi_wr, int post_len) NORETURN;
static NOINLINE void cgi_io_loop_and_exit(int fromCgi_rd, int toCgi_wr, int post_len)
{
enum { FROM_CGI = 1, TO_CGI = 2 }; /* indexes in pfd[] */
struct pollfd pfd[3];
int out_cnt; /* we buffer a bit of initial CGI output */
int count;
/* iobuf is used for CGI -> network data,
* hdr_buf is for network -> CGI data (POSTDATA) */
/* If CGI dies, we still want to correctly finish reading its output
* and send it to the peer. So please no SIGPIPEs! */
signal(SIGPIPE, SIG_IGN);
// We inconsistently handle a case when more POSTDATA from network
// is coming than we expected. We may give *some part* of that
// extra data to CGI.
//if (hdr_cnt > post_len) {
// /* We got more POSTDATA from network than we expected */
// hdr_cnt = post_len;
//}
post_len -= hdr_cnt;
/* post_len - number of POST bytes not yet read from network */
/* NB: breaking out of this loop jumps to log_and_exit() */
out_cnt = 0;
pfd[FROM_CGI].fd = fromCgi_rd;
pfd[FROM_CGI].events = POLLIN;
pfd[TO_CGI].fd = toCgi_wr;
while (1) {
/* Note: even pfd[0].events == 0 won't prevent
* revents == POLLHUP|POLLERR reports from closed stdin.
* Setting fd to -1 works: */
pfd[0].fd = -1;
pfd[0].events = POLLIN;
pfd[0].revents = 0; /* probably not needed, paranoia */
/* We always poll this fd, thus kernel always sets revents: */
/*pfd[FROM_CGI].events = POLLIN; - moved out of loop */
/*pfd[FROM_CGI].revents = 0; - not needed */
/* gcc-4.8.0 still doesnt fill two shorts with one insn :( */
/* http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47059 */
/* hopefully one day it will... */
pfd[TO_CGI].events = POLLOUT;
pfd[TO_CGI].revents = 0; /* needed! */
if (toCgi_wr && hdr_cnt <= 0) {
if (post_len > 0) {
/* Expect more POST data from network */
pfd[0].fd = 0;
} else {
/* post_len <= 0 && hdr_cnt <= 0:
* no more POST data to CGI,
* let CGI see EOF on CGI's stdin */
if (toCgi_wr != fromCgi_rd)
close(toCgi_wr);
toCgi_wr = 0;
}
}
/* Now wait on the set of sockets */
count = safe_poll(pfd, hdr_cnt > 0 ? TO_CGI+1 : FROM_CGI+1, -1);
if (count <= 0) {
#if 0
if (safe_waitpid(pid, &status, WNOHANG) <= 0) {
/* Weird. CGI didn't exit and no fd's
* are ready, yet poll returned?! */
continue;
}
if (DEBUG && WIFEXITED(status))
bb_error_msg("CGI exited, status=%u", WEXITSTATUS(status));
if (DEBUG && WIFSIGNALED(status))
bb_error_msg("CGI killed, signal=%u", WTERMSIG(status));
#endif
break;
}
if (pfd[TO_CGI].revents) {
/* hdr_cnt > 0 here due to the way poll() called */
/* Have data from peer and can write to CGI */
count = safe_write(toCgi_wr, hdr_ptr, hdr_cnt);
/* Doesn't happen, we dont use nonblocking IO here
*if (count < 0 && errno == EAGAIN) {
* ...
*} else */
if (count > 0) {
hdr_ptr += count;
hdr_cnt -= count;
} else {
/* EOF/broken pipe to CGI, stop piping POST data */
hdr_cnt = post_len = 0;
}
}
if (pfd[0].revents) {
/* post_len > 0 && hdr_cnt == 0 here */
/* We expect data, prev data portion is eaten by CGI
* and there *is* data to read from the peer
* (POSTDATA) */
//count = post_len > (int)sizeof_hdr_buf ? (int)sizeof_hdr_buf : post_len;
//count = safe_read(STDIN_FILENO, hdr_buf, count);
count = safe_read(STDIN_FILENO, hdr_buf, sizeof_hdr_buf);
if (count > 0) {
hdr_cnt = count;
hdr_ptr = hdr_buf;
post_len -= count;
} else {
/* no more POST data can be read */
post_len = 0;
}
}
if (pfd[FROM_CGI].revents) {
/* There is something to read from CGI */
char *rbuf = iobuf;
/* Are we still buffering CGI output? */
if (out_cnt >= 0) {
/* HTTP_200[] has single "\r\n" at the end.
* According to http://hoohoo.ncsa.uiuc.edu/cgi/out.html,
* CGI scripts MUST send their own header terminated by
* empty line, then data. That's why we have only one
* <cr><lf> pair here. We will output "200 OK" line
* if needed, but CGI still has to provide blank line
* between header and body */
/* Must use safe_read, not full_read, because
* CGI may output a few first bytes and then wait
* for POSTDATA without closing stdout.
* With full_read we may wait here forever. */
count = safe_read(fromCgi_rd, rbuf + out_cnt, IOBUF_SIZE - 8);
if (count <= 0) {
/* eof (or error) and there was no "HTTP",
* send "HTTP/1.1 200 OK\r\n", then send received data */
if (out_cnt) {
full_write(STDOUT_FILENO, HTTP_200, sizeof(HTTP_200)-1);
full_write(STDOUT_FILENO, rbuf, out_cnt);
}
break; /* CGI stdout is closed, exiting */
}
out_cnt += count;
count = 0;
/* "Status" header format is: "Status: 302 Redirected\r\n" */
if (out_cnt >= 8 && memcmp(rbuf, "Status: ", 8) == 0) {
/* send "HTTP/1.1 " */
if (full_write(STDOUT_FILENO, HTTP_200, 9) != 9)
break;
/* skip "Status: " (including space, sending "HTTP/1.1 NNN" is wrong) */
rbuf += 8;
count = out_cnt - 8;
out_cnt = -1; /* buffering off */
} else if (out_cnt >= 4) {
/* Did CGI add "HTTP"? */
if (memcmp(rbuf, HTTP_200, 4) != 0) {
/* there is no "HTTP", do it ourself */
if (full_write(STDOUT_FILENO, HTTP_200, sizeof(HTTP_200)-1) != sizeof(HTTP_200)-1)
break;
}
/* Commented out:
if (!strstr(rbuf, "ontent-")) {
full_write(s, "Content-type: text/plain\r\n\r\n", 28);
}
* Counter-example of valid CGI without Content-type:
* echo -en "HTTP/1.1 302 Found\r\n"
* echo -en "Location: http://www.busybox.net\r\n"
* echo -en "\r\n"
*/
count = out_cnt;
out_cnt = -1; /* buffering off */
}
} else {
count = safe_read(fromCgi_rd, rbuf, IOBUF_SIZE);
if (count <= 0)
break; /* eof (or error) */
}
if (full_write(STDOUT_FILENO, rbuf, count) != count)
break;
dbg("cgi read %d bytes: '%.*s'\n", count, count, rbuf);
} /* if (pfd[FROM_CGI].revents) */
} /* while (1) */
log_and_exit();
}
#endif
#if ENABLE_FEATURE_HTTPD_CGI
static void setenv1(const char *name, const char *value)
{
setenv(name, value ? value : "", 1);
}
/*
* Spawn CGI script, forward CGI's stdin/out <=> network
*
* Environment variables are set up and the script is invoked with pipes
* for stdin/stdout. If a POST is being done the script is fed the POST
* data in addition to setting the QUERY_STRING variable (for GETs or POSTs).
*
* Parameters:
* const char *url The requested URL (with leading /).
* const char *orig_uri The original URI before rewriting (if any)
* int post_len Length of the POST body.
*/
static void send_cgi_and_exit(
const char *url,
const char *orig_uri,
const char *request,
int post_len) NORETURN;
static void send_cgi_and_exit(
const char *url,
const char *orig_uri,
const char *request,
int post_len)
{
struct fd_pair fromCgi; /* CGI -> httpd pipe */
struct fd_pair toCgi; /* httpd -> CGI pipe */
char *script, *last_slash;
int pid;
/* Make a copy. NB: caller guarantees:
* url[0] == '/', url[1] != '/' */
url = xstrdup(url);
/*
* We are mucking with environment _first_ and then vfork/exec,
* this allows us to use vfork safely. Parent doesn't care about
* these environment changes anyway.
*/
/* Check for [dirs/]script.cgi/PATH_INFO */
last_slash = script = (char*)url;
while ((script = strchr(script + 1, '/')) != NULL) {
int dir;
*script = '\0';
dir = is_directory(url + 1, /*followlinks:*/ 1);
*script = '/';
if (!dir) {
/* not directory, found script.cgi/PATH_INFO */
break;
}
/* is directory, find next '/' */
last_slash = script;
}
setenv1("PATH_INFO", script); /* set to /PATH_INFO or "" */
setenv1("REQUEST_METHOD", request);
if (g_query) {
putenv(xasprintf("%s=%s?%s", "REQUEST_URI", orig_uri, g_query));
} else {
setenv1("REQUEST_URI", orig_uri);
}
if (script != NULL)
*script = '\0'; /* cut off /PATH_INFO */
/* SCRIPT_FILENAME is required by PHP in CGI mode */
if (home_httpd[0] == '/') {
char *fullpath = concat_path_file(home_httpd, url);
setenv1("SCRIPT_FILENAME", fullpath);
}
/* set SCRIPT_NAME as full path: /cgi-bin/dirs/script.cgi */
setenv1("SCRIPT_NAME", url);
/* http://hoohoo.ncsa.uiuc.edu/cgi/env.html:
* QUERY_STRING: The information which follows the ? in the URL
* which referenced this script. This is the query information.
* It should not be decoded in any fashion. This variable
* should always be set when there is query information,
* regardless of command line decoding. */
/* (Older versions of bbox seem to do some decoding) */
setenv1("QUERY_STRING", g_query);
putenv((char*)"SERVER_SOFTWARE=busybox httpd/"BB_VER);
putenv((char*)"SERVER_PROTOCOL=HTTP/1.1");
putenv((char*)"GATEWAY_INTERFACE=CGI/1.1");
/* Having _separate_ variables for IP and port defeats
* the purpose of having socket abstraction. Which "port"
* are you using on Unix domain socket?
* IOW - REMOTE_PEER="1.2.3.4:56" makes much more sense.
* Oh well... */
{
char *p = rmt_ip_str ? rmt_ip_str : (char*)"";
char *cp = strrchr(p, ':');
if (ENABLE_FEATURE_IPV6 && cp && strchr(cp, ']'))
cp = NULL;
if (cp) *cp = '\0'; /* delete :PORT */
setenv1("REMOTE_ADDR", p);
if (cp) {
*cp = ':';
#if ENABLE_FEATURE_HTTPD_SET_REMOTE_PORT_TO_ENV
setenv1("REMOTE_PORT", cp + 1);
#endif
}
}
if (post_len)
putenv(xasprintf("CONTENT_LENGTH=%u", post_len));
#if ENABLE_FEATURE_HTTPD_BASIC_AUTH
if (remoteuser) {
setenv1("REMOTE_USER", remoteuser);
putenv((char*)"AUTH_TYPE=Basic");
}
#endif
/* setenv1("SERVER_NAME", safe_gethostname()); - don't do this,
* just run "env SERVER_NAME=xyz httpd ..." instead */
xpiped_pair(fromCgi);
xpiped_pair(toCgi);
pid = vfork();
if (pid < 0) {
/* TODO: log perror? */
log_and_exit();
}
if (pid == 0) {
/* Child process */
char *argv[3];
xfunc_error_retval = 242;
/* NB: close _first_, then move fds! */
close(toCgi.wr);
close(fromCgi.rd);
xmove_fd(toCgi.rd, 0); /* replace stdin with the pipe */
xmove_fd(fromCgi.wr, 1); /* replace stdout with the pipe */
/* User seeing stderr output can be a security problem.
* If CGI really wants that, it can always do dup itself. */
/* dup2(1, 2); */
/* Chdiring to script's dir */
script = last_slash;
if (script != url) { /* paranoia */
*script = '\0';
if (chdir(url + 1) != 0) {
bb_perror_msg("can't change directory to '%s'", url + 1);
goto error_execing_cgi;
}
// not needed: *script = '/';
}
script++;
/* set argv[0] to name without path */
argv[0] = script;
argv[1] = NULL;
#if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
{
char *suffix = strrchr(script, '.');
if (suffix) {
Htaccess *cur;
for (cur = script_i; cur; cur = cur->next) {
if (strcmp(cur->before_colon + 1, suffix) == 0) {
/* found interpreter name */
argv[0] = cur->after_colon;
argv[1] = script;
argv[2] = NULL;
break;
}
}
}
}
#endif
/* restore default signal dispositions for CGI process */
bb_signals(0
| (1 << SIGCHLD)
| (1 << SIGPIPE)
| (1 << SIGHUP)
, SIG_DFL);
/* _NOT_ execvp. We do not search PATH. argv[0] is a filename
* without any dir components and will only match a file
* in the current directory */
execv(argv[0], argv);
if (verbose)
bb_perror_msg("can't execute '%s'", argv[0]);
error_execing_cgi:
/* send to stdout
* (we are CGI here, our stdout is pumped to the net) */
send_headers_and_exit(HTTP_NOT_FOUND);
} /* end child */
/* Parent process */
/* Restore variables possibly changed by child */
xfunc_error_retval = 0;
/* Pump data */
close(fromCgi.wr);
close(toCgi.rd);
cgi_io_loop_and_exit(fromCgi.rd, toCgi.wr, post_len);
}
#endif /* FEATURE_HTTPD_CGI */
/*
* Send a file response to a HTTP request, and exit
*
* Parameters:
* const char *url The requested URL (with leading /).
* what What to send (headers/body/both).
*/
static NOINLINE void send_file_and_exit(const char *url, int what)
{
char *suffix;
int fd;
ssize_t count;
if (content_gzip) {
/* does <url>.gz exist? Then use it instead */
char *gzurl = xasprintf("%s.gz", url);
fd = open(gzurl, O_RDONLY);
free(gzurl);
if (fd != -1) {
struct stat sb;
fstat(fd, &sb);
file_size = sb.st_size;
last_mod = sb.st_mtime;
} else {
IF_FEATURE_HTTPD_GZIP(content_gzip = 0;)
fd = open(url, O_RDONLY);
}
} else {
fd = open(url, O_RDONLY);
/* file_size and last_mod are already populated */
}
if (fd < 0) {
dbg("can't open '%s'\n", url);
/* Error pages are sent by using send_file_and_exit(SEND_BODY).
* IOW: it is unsafe to call send_headers_and_exit
* if what is SEND_BODY! Can recurse! */
if (what != SEND_BODY)
send_headers_and_exit(HTTP_NOT_FOUND);
log_and_exit();
}
#if ENABLE_FEATURE_HTTPD_ETAG
/* ETag is "hex(last_mod)-hex(file_size)" e.g. "5e132e20-417" */
sprintf(G.etag, "\"%llx-%llx\"", (unsigned long long)last_mod, (unsigned long long)file_size);
if (G.if_none_match) {
dbg("If-None-Match:'%s' file's ETag:'%s'\n", G.if_none_match, G.etag);
/* Weak ETag comparision.
* If-None-Match may have many ETags but they are quoted so we can use simple substring search */
if (strstr(G.if_none_match, G.etag))
send_headers_and_exit(HTTP_NOT_MODIFIED);
}
#endif
/* If you want to know about EPIPE below
* (happens if you abort downloads from local httpd): */
signal(SIGPIPE, SIG_IGN);
/* If not found, default is to not send "Content-type:" */
/*found_mime_type = NULL; - already is */
suffix = strrchr(url, '.');
if (suffix) {
static const char suffixTable[] ALIGN1 =
/* Shorter suffix must be first:
* ".html.htm" will fail for ".htm"
*/
".txt.h.c.cc.cpp\0" "text/plain\0"
/* .htm line must be after .h line */
".htm.html\0" "text/html\0"
".jpg.jpeg\0" "image/jpeg\0"
".gif\0" "image/gif\0"
".png\0" "image/png\0"
".svg\0" "image/svg+xml\0"
/* .css line must be after .c line */
".css\0" "text/css\0"
".js\0" "application/javascript\0"
".wav\0" "audio/wav\0"
".avi\0" "video/x-msvideo\0"
".qt.mov\0" "video/quicktime\0"
".mpe.mpeg\0" "video/mpeg\0"
".mid.midi\0" "audio/midi\0"
".mp3\0" "audio/mpeg\0"
#if 0 /* unpopular */
".au\0" "audio/basic\0"
".pac\0" "application/x-ns-proxy-autoconfig\0"
".vrml.wrl\0" "model/vrml\0"
#endif
/* compiler adds another "\0" here */
;
Htaccess *cur;
/* Examine built-in table */
const char *table = suffixTable;
const char *table_next;
for (; *table; table = table_next) {
const char *try_suffix;
const char *mime_type;
mime_type = table + strlen(table) + 1;
table_next = mime_type + strlen(mime_type) + 1;
try_suffix = strstr(table, suffix);
if (!try_suffix)
continue;
try_suffix += strlen(suffix);
if (*try_suffix == '\0' || *try_suffix == '.') {
found_mime_type = mime_type;
break;
}
/* Example: strstr(table, ".av") != NULL, but it
* does not match ".avi" after all and we end up here.
* The table is arranged so that in this case we know
* that it can't match anything in the following lines,
* and we stop the search: */
break;
}
/* ...then user's table */
for (cur = mime_a; cur; cur = cur->next) {
if (strcmp(cur->before_colon, suffix) == 0) {
found_mime_type = cur->after_colon;
break;
}
}
}
dbg("sending file '%s' content-type:%s\n", url, found_mime_type);
#if ENABLE_FEATURE_HTTPD_RANGES
if (what == SEND_BODY /* err pages and ranges don't mix */
|| content_gzip /* we are sending compressed page: can't do ranges */ ///why?
) {
range_start = -1;
}
range_len = MAXINT(off_t);
if (range_start >= 0) {
if (!range_end || range_end > file_size - 1) {
range_end = file_size - 1;
}
if (range_end < range_start
|| lseek(fd, range_start, SEEK_SET) != range_start
) {
lseek(fd, 0, SEEK_SET);
range_start = -1;
} else {
range_len = range_end - range_start + 1;
send_headers(HTTP_PARTIAL_CONTENT);
what = SEND_BODY;
}
}
#endif
if (what & SEND_HEADERS)
send_headers(HTTP_OK);
#if ENABLE_FEATURE_USE_SENDFILE
{
off_t offset;
if (range_start < 0)
range_start = 0;
offset = range_start;
while (1) {
/* sz is rounded down to 64k */
ssize_t sz = MAXINT(ssize_t) - 0xffff;
IF_FEATURE_HTTPD_RANGES(if (sz > range_len) sz = range_len;)
count = sendfile(STDOUT_FILENO, fd, &offset, sz);
if (count < 0) {
if (offset == range_start) /* was it the very 1st sendfile? */
break; /* fall back to read/write loop */
goto fin;
}
IF_FEATURE_HTTPD_RANGES(range_len -= count;)
if (count == 0 || range_len == 0)
log_and_exit();
}
}
#endif
while ((count = safe_read(fd, iobuf, IOBUF_SIZE)) > 0) {
ssize_t n;
IF_FEATURE_HTTPD_RANGES(if (count > range_len) count = range_len;)
n = full_write(STDOUT_FILENO, iobuf, count);
if (count != n)
break;
IF_FEATURE_HTTPD_RANGES(range_len -= count;)
if (range_len == 0)
break;
}
if (count < 0) {
IF_FEATURE_USE_SENDFILE(fin:)
if (verbose > 1)
bb_simple_perror_msg("error");
}
log_and_exit();
}
#if ENABLE_FEATURE_HTTPD_ACL_IP
static void if_ip_denied_send_HTTP_FORBIDDEN_and_exit(unsigned remote_ip)
{
Htaccess_IP *cur;
for (cur = G.ip_a_d; cur; cur = cur->next) {
dbg("checkPermIP: '%s' ? '%u.%u.%u.%u/%u.%u.%u.%u'\n",
rmt_ip_str,
(unsigned char)(cur->ip >> 24),
(unsigned char)(cur->ip >> 16),
(unsigned char)(cur->ip >> 8),
(unsigned char)(cur->ip),
(unsigned char)(cur->mask >> 24),
(unsigned char)(cur->mask >> 16),
(unsigned char)(cur->mask >> 8),
(unsigned char)(cur->mask)
);
if ((remote_ip & cur->mask) == cur->ip) {
if (cur->allow_deny == 'A')
return;
send_headers_and_exit(HTTP_FORBIDDEN);
}
}
if (flg_deny_all) /* depends on whether we saw "D:*" */
send_headers_and_exit(HTTP_FORBIDDEN);
}
#else
# define if_ip_denied_send_HTTP_FORBIDDEN_and_exit(arg) ((void)0)
#endif
#if ENABLE_FEATURE_HTTPD_BASIC_AUTH
# if ENABLE_PAM
struct pam_userinfo {
const char *name;
const char *pw;
};
static int pam_talker(int num_msg,
const struct pam_message **msg,
struct pam_response **resp,
void *appdata_ptr)
{
int i;
struct pam_userinfo *userinfo = (struct pam_userinfo *) appdata_ptr;
struct pam_response *response;
if (!resp || !msg || !userinfo)
return PAM_CONV_ERR;
/* allocate memory to store response */
response = xzalloc(num_msg * sizeof(*response));
/* copy values */
for (i = 0; i < num_msg; i++) {
const char *s;
switch (msg[i]->msg_style) {
case PAM_PROMPT_ECHO_ON:
s = userinfo->name;
break;
case PAM_PROMPT_ECHO_OFF:
s = userinfo->pw;
break;
case PAM_ERROR_MSG:
case PAM_TEXT_INFO:
s = "";
break;
default:
free(response);
return PAM_CONV_ERR;
}
response[i].resp = xstrdup(s);
if (PAM_SUCCESS != 0)
response[i].resp_retcode = PAM_SUCCESS;
}
*resp = response;
return PAM_SUCCESS;
}
# endif
/*
* Config file entries are of the form "/<path>:<user>:<passwd>".
* If config file has no prefix match for path, access is allowed.
*
* path The file path
* user_and_passwd "user:passwd" to validate
*
* Returns 1 if user_and_passwd is OK.
*/
static int check_user_passwd(const char *path, char *user_and_passwd)
{
Htaccess *cur;
const char *prev = NULL;
for (cur = g_auth; cur; cur = cur->next) {
const char *dir_prefix;
size_t len;
int r;
dir_prefix = cur->before_colon;
/* WHY? */
/* If already saw a match, don't accept other different matches */
if (prev && strcmp(prev, dir_prefix) != 0)
continue;
dbg("checkPerm: '%s' ? '%s'\n", dir_prefix, user_and_passwd);
/* If it's not a prefix match, continue searching */
len = strlen(dir_prefix);
if (len != 1 /* dir_prefix "/" matches all, don't need to check */
&& (strncmp(dir_prefix, path, len) != 0
|| (path[len] != '/' && path[len] != '\0')
)
) {
continue;
}
/* Path match found */
prev = dir_prefix;
if (ENABLE_FEATURE_HTTPD_AUTH_MD5) {
char *colon_after_user;
const char *passwd;
# if ENABLE_FEATURE_SHADOWPASSWDS && !ENABLE_PAM
char sp_buf[256];
# endif
colon_after_user = strchr(user_and_passwd, ':');
if (!colon_after_user)
goto bad_input;
/* compare "user:" */
if (cur->after_colon[0] != '*'
&& strncmp(cur->after_colon, user_and_passwd,
colon_after_user - user_and_passwd + 1) != 0
) {
continue;
}
/* this cfg entry is '*' or matches username from peer */
passwd = strchr(cur->after_colon, ':');
if (!passwd)
goto bad_input;
passwd++;
if (passwd[0] == '*') {
# if ENABLE_PAM
struct pam_userinfo userinfo;
struct pam_conv conv_info = { &pam_talker, (void *) &userinfo };
pam_handle_t *pamh;
*colon_after_user = '\0';
userinfo.name = user_and_passwd;
userinfo.pw = colon_after_user + 1;
r = pam_start("httpd", user_and_passwd, &conv_info, &pamh) != PAM_SUCCESS;
if (r == 0) {
r = pam_authenticate(pamh, PAM_DISALLOW_NULL_AUTHTOK) != PAM_SUCCESS
|| pam_acct_mgmt(pamh, PAM_DISALLOW_NULL_AUTHTOK) != PAM_SUCCESS
;
pam_end(pamh, PAM_SUCCESS);
}
*colon_after_user = ':';
goto end_check_passwd;
# else
# if ENABLE_FEATURE_SHADOWPASSWDS
/* Using _r function to avoid pulling in static buffers */
struct spwd spw;
# endif
struct passwd *pw;
*colon_after_user = '\0';
pw = getpwnam(user_and_passwd);
*colon_after_user = ':';
if (!pw || !pw->pw_passwd)
continue;
passwd = pw->pw_passwd;
# if ENABLE_FEATURE_SHADOWPASSWDS
if ((passwd[0] == 'x' || passwd[0] == '*') && !passwd[1]) {
/* getspnam_r may return 0 yet set result to NULL.
* At least glibc 2.4 does this. Be extra paranoid here. */
struct spwd *result = NULL;
r = getspnam_r(pw->pw_name, &spw, sp_buf, sizeof(sp_buf), &result);
if (r == 0 && result)
passwd = result->sp_pwdp;
}
# endif
/* In this case, passwd is ALWAYS encrypted:
* it came from /etc/passwd or /etc/shadow!
*/
goto check_encrypted;
# endif /* ENABLE_PAM */
}
/* Else: passwd is from httpd.conf, it is either plaintext or encrypted */
if (passwd[0] == '$' && isdigit(passwd[1])) {
char *encrypted;
# if !ENABLE_PAM
check_encrypted:
# endif
/* encrypt pwd from peer and check match with local one */
encrypted = pw_encrypt(
/* pwd (from peer): */ colon_after_user + 1,
/* salt: */ passwd,
/* cleanup: */ 0
);
r = strcmp(encrypted, passwd);
free(encrypted);
} else {
/* local passwd is from httpd.conf and it's plaintext */
r = strcmp(colon_after_user + 1, passwd);
}
goto end_check_passwd;
}
bad_input:
/* Comparing plaintext "user:pass" in one go */
r = strcmp(cur->after_colon, user_and_passwd);
end_check_passwd:
if (r == 0) {
remoteuser = xstrndup(user_and_passwd,
strchrnul(user_and_passwd, ':') - user_and_passwd
);
return 1; /* Ok */
}
} /* for */
/* 0(bad) if prev is set: matches were found but passwd was wrong */
return (prev == NULL);
}
#endif /* FEATURE_HTTPD_BASIC_AUTH */
#if ENABLE_FEATURE_HTTPD_PROXY
static Htaccess_Proxy *find_proxy_entry(const char *url)
{
Htaccess_Proxy *p;
for (p = proxy; p; p = p->next) {
if (is_prefixed_with(url, p->url_from))
return p;
}
return NULL;
}
#endif
/*
* Handle timeouts
*/
static void send_REQUEST_TIMEOUT_and_exit(int sig) NORETURN;
static void send_REQUEST_TIMEOUT_and_exit(int sig UNUSED_PARAM)
{
send_headers_and_exit(HTTP_REQUEST_TIMEOUT);
}
/*
* Handle an incoming http request and exit.
*/
static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr) NORETURN;
static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
{
struct stat sb;
char *urlcopy;
char *urlp;
char *tptr;
#if ENABLE_FEATURE_HTTPD_ACL_IP
unsigned remote_ip;
#endif
#if ENABLE_FEATURE_HTTPD_CGI
unsigned total_headers_len;
#endif
const char *prequest;
static const char request_GET[] ALIGN1 = "GET";
static const char request_HEAD[] ALIGN1 = "HEAD";
#if ENABLE_FEATURE_HTTPD_CGI
static const char request_POST[] ALIGN1 = "POST";
unsigned long POST_length;
enum CGI_type {
CGI_NONE = 0,
CGI_NORMAL,
CGI_INDEX,
CGI_INTERPRETER,
} cgi_type = CGI_NONE;
#endif
#if ENABLE_FEATURE_HTTPD_PROXY
Htaccess_Proxy *proxy_entry;
#endif
#if ENABLE_FEATURE_HTTPD_BASIC_AUTH
smallint authorized = -1;
#endif
char *HTTP_slash;
/* Allocation of iobuf is postponed until now
* (IOW, server process doesn't need to waste 8k) */
iobuf = xmalloc(IOBUF_SIZE);
if (ENABLE_FEATURE_HTTPD_CGI || DEBUG || verbose) {
/* NB: can be NULL (user runs httpd -i by hand?) */
rmt_ip_str = xmalloc_sockaddr2dotted(&fromAddr->u.sa);
}
if (verbose) {
/* this trick makes -v logging much simpler */
if (rmt_ip_str)
applet_name = rmt_ip_str;
if (verbose > 2)
bb_simple_error_msg("connected");
}
#if ENABLE_FEATURE_HTTPD_ACL_IP
remote_ip = 0;
if (fromAddr->u.sa.sa_family == AF_INET) {
remote_ip = ntohl(fromAddr->u.sin.sin_addr.s_addr);
}
# if ENABLE_FEATURE_IPV6
if (fromAddr->u.sa.sa_family == AF_INET6
&& fromAddr->u.sin6.sin6_addr.s6_addr32[0] == 0
&& fromAddr->u.sin6.sin6_addr.s6_addr32[1] == 0
&& ntohl(fromAddr->u.sin6.sin6_addr.s6_addr32[2]) == 0xffff)
remote_ip = ntohl(fromAddr->u.sin6.sin6_addr.s6_addr32[3]);
# endif
if_ip_denied_send_HTTP_FORBIDDEN_and_exit(remote_ip);
#endif
/* Install timeout handler. get_line() needs it. */
signal(SIGALRM, send_REQUEST_TIMEOUT_and_exit);
if (!get_line()) { /* EOF or error or empty line */
/* Observed Firefox to "speculatively" open
* extra connections to a new site on first access,
* they are closed in ~5 seconds with nothing
* being sent at all.
* (Presumably it's a method to decrease latency?)
*/
if (verbose > 2)
bb_simple_error_msg("eof on read, closing");
/* Don't bother generating error page in this case,
* just close the socket.
*/
//send_headers_and_exit(HTTP_BAD_REQUEST);
_exit(xfunc_error_retval);
}
dbg("Request:'%s'\n", iobuf);
/* Find URL */
// rfc2616: method and URI is separated by exactly one space
//urlp = strpbrk(iobuf, " \t"); - no, tab isn't allowed
urlp = strchr(iobuf, ' ');
if (urlp == NULL)
send_headers_and_exit(HTTP_BAD_REQUEST);
*urlp++ = '\0';
//urlp = skip_whitespace(urlp); - should not be necessary
if (urlp[0] != '/')
send_headers_and_exit(HTTP_BAD_REQUEST);
/* Find end of URL */
HTTP_slash = strchr(urlp, ' ');
/* Is it " HTTP/"? */
if (!HTTP_slash || strncmp(HTTP_slash + 1, HTTP_200, 5) != 0)
send_headers_and_exit(HTTP_BAD_REQUEST);
*HTTP_slash++ = '\0';
#if ENABLE_FEATURE_HTTPD_PROXY
proxy_entry = find_proxy_entry(urlp);
if (proxy_entry) {
int proxy_fd;
len_and_sockaddr *lsa;
if (verbose > 1)
bb_error_msg("proxy:%s", urlp);
lsa = host2sockaddr(proxy_entry->host_port, 80);
if (!lsa)
send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
proxy_fd = socket(lsa->u.sa.sa_family, SOCK_STREAM, 0);
if (proxy_fd < 0)
send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
if (connect(proxy_fd, &lsa->u.sa, lsa->len) < 0)
send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
/* Disable peer header reading timeout */
alarm(0);
/* Config directive was of the form:
* P:/url:[http://]hostname[:port]/new/path
* When /urlSFX is requested, reverse proxy it
* to http://hostname[:port]/new/pathSFX
*/
fdprintf(proxy_fd, "%s %s%s %s\r\n",
iobuf, /* "GET" / "POST" / etc */
proxy_entry->url_to, /* "/new/path" */
urlp + strlen(proxy_entry->url_from), /* "SFX" */
HTTP_slash /* "HTTP/xyz" */
);
cgi_io_loop_and_exit(proxy_fd, proxy_fd, /*max POST length:*/ INT_MAX);
}
#endif
/* Determine type of request (GET/POST/...) */
prequest = request_GET;
if (strcasecmp(iobuf, prequest) == 0)
goto found;
prequest = request_HEAD;
if (strcasecmp(iobuf, prequest) == 0)
goto found;
#if !ENABLE_FEATURE_HTTPD_CGI
send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
#else
prequest = request_POST;
if (strcasecmp(iobuf, prequest) == 0)
goto found;
/* For CGI, allow DELETE, PUT, OPTIONS, etc too */
prequest = alloca(16);
safe_strncpy((char*)prequest, iobuf, 16);
#endif
found:
/* Copy URL to stack-allocated char[] */
urlcopy = alloca((HTTP_slash - urlp) + 2 + strlen(index_page));
strcpy(urlcopy, urlp);
/* NB: urlcopy ptr is never changed after this */
/* Extract url args if present */
g_query = strchr(urlcopy, '?');
if (g_query)
*g_query++ = '\0';
/* Decode URL escape sequences */
tptr = percent_decode_in_place(urlcopy, /*strict:*/ 1);
if (tptr == NULL)
send_headers_and_exit(HTTP_BAD_REQUEST);
if (tptr == urlcopy + 1) {
/* '/' or NUL is encoded */
send_headers_and_exit(HTTP_NOT_FOUND);
}
/* Canonicalize path */
/* Algorithm stolen from libbb bb_simplify_path(),
* but don't strdup, retain trailing slash, protect root */
urlp = tptr = urlcopy;
while (1) {
if (*urlp == '/') {
/* skip duplicate (or initial) slash */
if (*tptr == '/') {
goto next_char;
}
if (*tptr == '.') {
if (tptr[1] == '.' && (tptr[2] == '/' || tptr[2] == '\0')) {
/* "..": be careful */
/* protect root */
if (urlp == urlcopy)
send_headers_and_exit(HTTP_BAD_REQUEST);
/* omit previous dir */
while (*--urlp != '/')
continue;
/* skip to "./" or ".<NUL>" */
tptr++;
}
if (tptr[1] == '/' || tptr[1] == '\0') {
/* skip extra "/./" */
goto next_char;
}
}
}
*++urlp = *tptr;
if (*tptr == '\0')
break;
next_char:
tptr++;
}
/* Log it */
if (verbose > 1)
bb_error_msg("url:%s", urlcopy);
tptr = urlcopy;
while ((tptr = strchr(tptr + 1, '/')) != NULL) {
/* have path1/path2 */
*tptr = '\0';
/* may have subdir config */
if (parse_conf(urlcopy + 1, SUBDIR_PARSE) == 0)
if_ip_denied_send_HTTP_FORBIDDEN_and_exit(remote_ip);
*tptr = '/';
}
tptr = urlcopy + 1; /* skip first '/' */
#if ENABLE_FEATURE_HTTPD_CGI
if (is_prefixed_with(tptr, "cgi-bin/")) {
if (tptr[8] == '\0') {
/* protect listing "cgi-bin/" */
send_headers_and_exit(HTTP_FORBIDDEN);
}
cgi_type = CGI_NORMAL;
}
#endif
if (urlp[-1] == '/') {
/* When index_page string is appended to <dir>/ URL, it overwrites
* the query string. If we fall back to call /cgi-bin/index.cgi,
* query string would be lost and not available to the CGI.
* Work around it by making a deep copy.
*/
if (ENABLE_FEATURE_HTTPD_CGI)
g_query = xstrdup(g_query); /* ok for NULL too */
strcpy(urlp, index_page);
}
if (stat(tptr, &sb) == 0) {
/* If URL is a directory with no slash, set up
* "HTTP/1.1 302 Found" "Location: /dir/" reply */
if (urlp[-1] != '/' && S_ISDIR(sb.st_mode)) {
found_moved_temporarily = urlcopy;
} else {
#if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
char *suffix = strrchr(tptr, '.');
if (suffix) {
Htaccess *cur;
for (cur = script_i; cur; cur = cur->next) {
if (strcmp(cur->before_colon + 1, suffix) == 0) {
cgi_type = CGI_INTERPRETER;
break;
}
}
}
#endif
file_size = sb.st_size;
last_mod = sb.st_mtime;
}
}
#if ENABLE_FEATURE_HTTPD_CGI
else if (urlp[-1] == '/') {
/* It's a dir URL and there is no index.html */
/* Is there cgi-bin/index.cgi? */
if (access("/cgi-bin/index.cgi"+1, X_OK) != 0)
send_headers_and_exit(HTTP_NOT_FOUND); /* no */
cgi_type = CGI_INDEX;
}
#endif
#if ENABLE_FEATURE_HTTPD_BASIC_AUTH || ENABLE_FEATURE_HTTPD_CGI
/* check_user_passwd() would be confused by added .../index.html, truncate it */
urlp[0] = '\0';
#endif
#if ENABLE_FEATURE_HTTPD_CGI
total_headers_len = 0;
POST_length = 0;
#endif
/* Read until blank line */
while (1) {
unsigned iobuf_len = get_line();
if (!iobuf_len)
break; /* EOF or error or empty line */
#if ENABLE_FEATURE_HTTPD_CGI
/* Prevent unlimited growth of HTTP_xyz envvars */
total_headers_len += iobuf_len;
if (total_headers_len >= MAX_HTTP_HEADERS_SIZE)
send_headers_and_exit(HTTP_ENTITY_TOO_LARGE);
#endif
dbg("header:'%s'\n", iobuf);
#if ENABLE_FEATURE_HTTPD_CGI
/* Only POST needs to know POST_length */
if (prequest == request_POST && STRNCASECMP(iobuf, "Content-Length:") == 0) {
tptr = skip_whitespace(iobuf + sizeof("Content-Length:") - 1);
if (!tptr[0])
send_headers_and_exit(HTTP_BAD_REQUEST);
/* not using strtoul: it ignores leading minus! */
POST_length = bb_strtou(tptr, NULL, 10);
/* length is "ulong", but we need to pass it to int later */
if (errno || POST_length > INT_MAX)
send_headers_and_exit(HTTP_BAD_REQUEST);
continue;
}
#endif
#if ENABLE_FEATURE_HTTPD_BASIC_AUTH
if (STRNCASECMP(iobuf, "Authorization:") == 0) {
/* We only allow Basic credentials.
* It shows up as "Authorization: Basic <user>:<passwd>" where
* "<user>:<passwd>" is base64 encoded.
*/
tptr = skip_whitespace(iobuf + sizeof("Authorization:")-1);
if (STRNCASECMP(tptr, "Basic") == 0) {
tptr += sizeof("Basic")-1;
/* decodeBase64() skips whitespace itself */
decodeBase64(tptr);
authorized = check_user_passwd(urlcopy, tptr);
continue;
}
}
#endif
#if ENABLE_FEATURE_HTTPD_RANGES
if (STRNCASECMP(iobuf, "Range:") == 0) {
/* We know only bytes=NNN-[MMM] */
char *s = skip_whitespace(iobuf + sizeof("Range:")-1);
s = is_prefixed_with(s, "bytes=");
if (s) {
range_start = BB_STRTOOFF(s, &s, 10);
if (s[0] != '-' || range_start < 0) {
range_start = -1;
} else if (s[1]) {
range_end = BB_STRTOOFF(s+1, NULL, 10);
if (errno || range_end < range_start)
range_start = -1;
}
}
continue;
}
#endif
#if ENABLE_FEATURE_HTTPD_GZIP
if (STRNCASECMP(iobuf, "Accept-Encoding:") == 0) {
/* Note: we do not support "gzip;q=0"
* method of _disabling_ gzip
* delivery. No one uses that, though */
const char *s = strstr(iobuf, "gzip");
if (s) {
// want more thorough checks?
//if (s[-1] == ' '
// || s[-1] == ','
// || s[-1] == ':'
//) {
content_gzip = 1;
//}
}
continue;
}
#endif
#if ENABLE_FEATURE_HTTPD_ETAG
if (STRNCASECMP(iobuf, "If-None-Match:") == 0) {
free(G.if_none_match);
G.if_none_match = xstrdup(skip_whitespace(iobuf + sizeof("If-None-Match:") - 1));
continue;
}
#endif
#if ENABLE_FEATURE_HTTPD_CGI
if (cgi_type != CGI_NONE) {
bool ct = (STRNCASECMP(iobuf, "Content-Type:") == 0);
char *cp;
char *colon = strchr(iobuf, ':');
if (!colon)
continue;
cp = iobuf;
while (cp < colon) {
/* a-z => A-Z, not-alnum => _ */
char c = (*cp & ~0x20); /* toupper for A-Za-z, undef for others */
if ((unsigned)(c - 'A') <= ('Z' - 'A')) {
*cp++ = c;
continue;
}
if (!isdigit(*cp))
*cp = '_';
cp++;
}
/* "Content-Type:" gets no HTTP_ prefix, all others do */
cp = xasprintf(ct ? "HTTP_%.*s=%s" + 5 : "HTTP_%.*s=%s",
(int)(colon - iobuf), iobuf,
skip_whitespace(colon + 1)
);
putenv(cp);
}
#endif
} /* while extra header reading */
/* We are done reading headers, disable peer timeout */
alarm(0);
if (strcmp(bb_basename(urlcopy), HTTPD_CONF) == 0) {
/* protect listing [/path]/httpd.conf or IP deny */
send_headers_and_exit(HTTP_FORBIDDEN);
}
#if ENABLE_FEATURE_HTTPD_BASIC_AUTH
/* Case: no "Authorization:" was seen, but page might require passwd.
* Check that with dummy user:pass */
if (authorized < 0)
authorized = check_user_passwd(urlcopy, (char *) "");
if (!authorized)
send_headers_and_exit(HTTP_UNAUTHORIZED);
#endif
if (found_moved_temporarily)
send_headers_and_exit(HTTP_MOVED_TEMPORARILY);
#if ENABLE_FEATURE_HTTPD_CGI
if (cgi_type != CGI_NONE) {
send_cgi_and_exit(
(cgi_type == CGI_INDEX) ? "/cgi-bin/index.cgi"
/*CGI_NORMAL or CGI_INTERPRETER*/ : urlcopy,
urlcopy, prequest, POST_length
);
}
#endif
#if ENABLE_FEATURE_HTTPD_CGI
if (prequest != request_GET && prequest != request_HEAD) {
/* POST / DELETE / PUT / OPTIONS for files do not make sense */
send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
}
#else
/* !CGI: it can be only GET or HEAD */
#endif
#if ENABLE_FEATURE_HTTPD_BASIC_AUTH
/* Restore truncated .../index.html */
if (urlp[-1] == '/')
urlp[0] = index_page[0];
#endif
send_file_and_exit(urlcopy + 1,
(prequest != request_HEAD ? (SEND_HEADERS + SEND_BODY) : SEND_HEADERS)
);
}
/*
* The main http server function.
* Given a socket, listen for new connections and farm out
* the processing as a [v]forked process.
* Never returns.
*/
#if BB_MMU
static void mini_httpd(int server_socket) NORETURN;
static void mini_httpd(int server_socket)
{
/* NB: it's best to not use xfuncs in this loop before fork().
* Otherwise server may die on transient errors (temporary
* out-of-memory condition, etc), which is Bad(tm).
* Try to do any dangerous calls after fork.
*/
while (1) {
int n;
len_and_sockaddr fromAddr;
/* Wait for connections... */
fromAddr.len = LSA_SIZEOF_SA;
n = accept(server_socket, &fromAddr.u.sa, &fromAddr.len);
if (n < 0)
continue;
//TODO: we can reject connects from denied IPs right away;
//also, we might want to do one MSG_DONTWAIT'ed recv() here
//to detect immediate EOF,
//to avoid forking a whole new process for attackers
//who open and close lots of connections.
//(OTOH, the real mitigtion for this sort of thing is
//to ratelimit connects in iptables)
/* set the KEEPALIVE option to cull dead connections */
setsockopt_keepalive(n);
if (fork() == 0) {
/* child */
/* Do not reload config on HUP */
signal(SIGHUP, SIG_IGN);
close(server_socket);
xmove_fd(n, 0);
xdup2(0, 1);
handle_incoming_and_exit(&fromAddr);
}
/* parent, or fork failed */
close(n);
} /* while (1) */
/* never reached */
}
#else
static void mini_httpd_nommu(int server_socket, int argc, char **argv) NORETURN;
static void mini_httpd_nommu(int server_socket, int argc, char **argv)
{
char *argv_copy[argc + 2];
argv_copy[0] = argv[0];
argv_copy[1] = (char*)"-i";
memcpy(&argv_copy[2], &argv[1], argc * sizeof(argv[0]));
/* NB: it's best to not use xfuncs in this loop before vfork().
* Otherwise server may die on transient errors (temporary
* out-of-memory condition, etc), which is Bad(tm).
* Try to do any dangerous calls after fork.
*/
while (1) {
int n;
/* Wait for connections... */
n = accept(server_socket, NULL, NULL);
if (n < 0)
continue;
/* set the KEEPALIVE option to cull dead connections */
setsockopt_keepalive(n);
if (vfork() == 0) {
/* child */
/* Do not reload config on HUP */
signal(SIGHUP, SIG_IGN);
close(server_socket);
xmove_fd(n, 0);
xdup2(0, 1);
/* Run a copy of ourself in inetd mode */
re_exec(argv_copy);
}
argv_copy[0][0] &= 0x7f;
/* parent, or vfork failed */
close(n);
} /* while (1) */
/* never reached */
}
#endif
/*
* Process a HTTP connection on stdin/out.
* Never returns.
*/
static void mini_httpd_inetd(void) NORETURN;
static void mini_httpd_inetd(void)
{
len_and_sockaddr fromAddr;
memset(&fromAddr, 0, sizeof(fromAddr));
fromAddr.len = LSA_SIZEOF_SA;
/* NB: can fail if user runs it by hand and types in http cmds */
getpeername(0, &fromAddr.u.sa, &fromAddr.len);
handle_incoming_and_exit(&fromAddr);
}
static void sighup_handler(int sig UNUSED_PARAM)
{
int sv = errno;
parse_conf(DEFAULT_PATH_HTTPD_CONF, SIGNALED_PARSE);
errno = sv;
}
enum {
c_opt_config_file = 0,
d_opt_decode_url,
h_opt_home_httpd,
IF_FEATURE_HTTPD_ENCODE_URL_STR(e_opt_encode_url,)
IF_FEATURE_HTTPD_BASIC_AUTH( r_opt_realm ,)
IF_FEATURE_HTTPD_AUTH_MD5( m_opt_md5 ,)
IF_FEATURE_HTTPD_SETUID( u_opt_setuid ,)
p_opt_port ,
p_opt_inetd ,
p_opt_foreground,
p_opt_verbose ,
OPT_CONFIG_FILE = 1 << c_opt_config_file,
OPT_DECODE_URL = 1 << d_opt_decode_url,
OPT_HOME_HTTPD = 1 << h_opt_home_httpd,
OPT_ENCODE_URL = IF_FEATURE_HTTPD_ENCODE_URL_STR((1 << e_opt_encode_url)) + 0,
OPT_REALM = IF_FEATURE_HTTPD_BASIC_AUTH( (1 << r_opt_realm )) + 0,
OPT_MD5 = IF_FEATURE_HTTPD_AUTH_MD5( (1 << m_opt_md5 )) + 0,
OPT_SETUID = IF_FEATURE_HTTPD_SETUID( (1 << u_opt_setuid )) + 0,
OPT_PORT = 1 << p_opt_port,
OPT_INETD = 1 << p_opt_inetd,
OPT_FOREGROUND = 1 << p_opt_foreground,
OPT_VERBOSE = 1 << p_opt_verbose,
};
int httpd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int httpd_main(int argc UNUSED_PARAM, char **argv)
{
int server_socket = server_socket; /* for gcc */
unsigned opt;
char *url_for_decode;
IF_FEATURE_HTTPD_ENCODE_URL_STR(const char *url_for_encode;)
IF_FEATURE_HTTPD_SETUID(const char *s_ugid = NULL;)
IF_FEATURE_HTTPD_SETUID(struct bb_uidgid_t ugid;)
IF_FEATURE_HTTPD_AUTH_MD5(const char *pass;)
INIT_G();
#if ENABLE_LOCALE_SUPPORT
/* Undo busybox.c: we want to speak English in http (dates etc) */
setlocale(LC_TIME, "C");
#endif
home_httpd = xrealloc_getcwd_or_warn(NULL);
/* We do not "absolutize" path given by -h (home) opt.
* If user gives relative path in -h,
* $SCRIPT_FILENAME will not be set. */
opt = getopt32(argv, "^"
"c:d:h:"
IF_FEATURE_HTTPD_ENCODE_URL_STR("e:")
IF_FEATURE_HTTPD_BASIC_AUTH("r:")
IF_FEATURE_HTTPD_AUTH_MD5("m:")
IF_FEATURE_HTTPD_SETUID("u:")
"p:ifv"
"\0"
/* -v counts, -i implies -f */
"vv:if",
&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)
IF_FEATURE_HTTPD_SETUID(, &s_ugid)
, &bind_addr_or_port
, &verbose
);
if (opt & OPT_DECODE_URL) {
fputs_stdout(percent_decode_in_place(url_for_decode, /*strict:*/ 0));
return 0;
}
#if ENABLE_FEATURE_HTTPD_ENCODE_URL_STR
if (opt & OPT_ENCODE_URL) {
fputs_stdout(encodeString(url_for_encode));
return 0;
}
#endif
#if ENABLE_FEATURE_HTTPD_AUTH_MD5
if (opt & OPT_MD5) {
char salt[sizeof("$1$XXXXXXXX")];
salt[0] = '$';
salt[1] = '1';
salt[2] = '$';
crypt_make_salt(salt + 3, 4);
puts(pw_encrypt(pass, salt, /*cleanup:*/ 0));
return 0;
}
#endif
#if ENABLE_FEATURE_HTTPD_SETUID
if (opt & OPT_SETUID) {
xget_uidgid(&ugid, s_ugid);
}
#endif
#if !BB_MMU
if (!(opt & OPT_FOREGROUND)) {
bb_daemonize_or_rexec(0, argv); /* don't change current directory */
re_execed = 0; /* for the following chdir to work */
}
#endif
/* Chdir to home (unless we were re_exec()ed for NOMMU case
* in mini_httpd_nommu(): we are already in the home dir then).
*/
if (!re_execed)
xchdir(home_httpd);
if (!(opt & OPT_INETD)) {
signal(SIGCHLD, SIG_IGN);
server_socket = openServer();
#if ENABLE_FEATURE_HTTPD_SETUID
/* drop privileges */
if (opt & OPT_SETUID) {
if (ugid.gid != (gid_t)-1) {
if (setgroups(1, &ugid.gid) == -1)
bb_simple_perror_msg_and_die("setgroups");
xsetgid(ugid.gid);
}
xsetuid(ugid.uid);
}
#endif
}
#if 0
/* User can do it himself: 'env - PATH="$PATH" httpd'
* We don't do it because we don't want to screw users
* which want to do
* 'env - VAR1=val1 VAR2=val2 httpd'
* and have VAR1 and VAR2 values visible in their CGIs.
* Besides, it is also smaller. */
{
char *p = getenv("PATH");
/* env strings themself are not freed, no need to xstrdup(p): */
clearenv();
if (p)
putenv(p - 5);
// if (!(opt & OPT_INETD))
// setenv_long("SERVER_PORT", ???);
}
#endif
parse_conf(DEFAULT_PATH_HTTPD_CONF, FIRST_PARSE);
if (!(opt & OPT_INETD))
signal(SIGHUP, sighup_handler);
xfunc_error_retval = 0;
if (opt & OPT_INETD)
mini_httpd_inetd(); /* never returns */
#if BB_MMU
if (!(opt & OPT_FOREGROUND))
bb_daemonize(0); /* don't change current directory */
mini_httpd(server_socket); /* never returns */
#else
mini_httpd_nommu(server_socket, argc, argv); /* never returns */
#endif
/* return 0; */
}