diff options
| -rw-r--r-- | networking/httpd.c | 204 |
1 files changed, 110 insertions, 94 deletions
diff --git a/networking/httpd.c b/networking/httpd.c index c837d67..23d442f 100644 --- a/networking/httpd.c +++ b/networking/httpd.c @@ -110,6 +110,7 @@ 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 { struct has_next_ptr *next; @@ -135,6 +136,7 @@ struct globals { smallint flg_deny_all; unsigned rmt_ip; +// TODO: get rid of rmt_port unsigned rmt_port; /* for set env REMOTE_PORT */ char *rmt_ip_str; /* for set env REMOTE_ADDR */ const char *bind_addr_or_port; @@ -661,6 +663,22 @@ static char *encodeString(const char *string) * * Returns a pointer to the decoded string (same as input). */ +static unsigned hex_to_bin(unsigned char c) +{ + unsigned v = c | 0x20; /* lowercase */ + v = v - '0'; + if (v <= 9) + return v; + v = v + ('0' - 'a'); + if (v <= 5) + return v + 10; + return ~0; +} +/* For testing: +void t(char c) { printf("'%c' %u\n", c, hex_to_bin(c)); } +int main() { t('0'); t('9'); t('A'); t('F'); t('a'); t('f'); +t('0'-1); t('9'+1); t('A'-1); t('F'+1); t('a'-1); t('f'+1); return 0; } +*/ static char *decodeString(char *orig, int option_d) { /* note that decoded string is always shorter than original */ @@ -669,7 +687,7 @@ static char *decodeString(char *orig, int option_d) char c; while ((c = *ptr++) != '\0') { - unsigned value1, value2; + unsigned v; if (option_d && c == '+') { *string++ = ' '; @@ -679,21 +697,23 @@ static char *decodeString(char *orig, int option_d) *string++ = c; continue; } - if (sscanf(ptr, "%1X", &value1) != 1 - || sscanf(ptr+1, "%1X", &value2) != 1 - ) { + v = hex_to_bin(ptr[0]); + if (v > 15) { + bad_hex: if (!option_d) return NULL; *string++ = '%'; continue; } - value1 = value1 * 16 + value2; - if (!option_d && (value1 == '/' || value1 == '\0')) { + v = (v * 16) | hex_to_bin(ptr[1]); + if (v > 255) + goto bad_hex; + if (!option_d && (v == '/' || v == '\0')) { /* caller takes it as indication of invalid * (dangerous wrt exploits) chars */ return orig + 1; } - *string++ = value1; + *string++ = v; ptr += 2; } *string = '\0'; @@ -1188,13 +1208,13 @@ static void send_cgi_and_exit( /* Are we still buffering CGI output? */ if (buf_count >= 0) { - /* According to http://hoohoo.ncsa.uiuc.edu/cgi/out.html, + /* 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 */ - static const char HTTP_200[] ALIGN1 = "HTTP/1.0 200 OK\r\n"; /* Must use safe_read, not full_read, because * CGI may output a few first bytes and then wait @@ -1489,12 +1509,11 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr) { static const char request_GET[] ALIGN1 = "GET"; - char *url; - char *purl; - int count; - int http_major_version; - char *test; struct stat sb; + char *urlcopy; + char *urlp; + char *tptr; + int http_major_version; int ip_allowed; #if ENABLE_FEATURE_HTTPD_CGI const char *prequest; @@ -1535,58 +1554,57 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr) sigaction(SIGALRM, &sa, NULL); alarm(HEADER_READ_TIMEOUT); - if (!get_line()) { - /* EOF or error or empty line */ + if (!get_line()) /* EOF or error or empty line */ send_headers_and_exit(HTTP_BAD_REQUEST); - } /* Determine type of request (GET/POST) */ - purl = strpbrk(iobuf, " \t"); - if (purl == NULL) { + urlp = strpbrk(iobuf, " \t"); + if (urlp == NULL) send_headers_and_exit(HTTP_BAD_REQUEST); - } - *purl = '\0'; + *urlp++ = '\0'; #if ENABLE_FEATURE_HTTPD_CGI prequest = request_GET; if (strcasecmp(iobuf, prequest) != 0) { prequest = "POST"; - if (strcasecmp(iobuf, prequest) != 0) { + if (strcasecmp(iobuf, prequest) != 0) send_headers_and_exit(HTTP_NOT_IMPLEMENTED); - } } #else - if (strcasecmp(iobuf, request_GET) != 0) { + if (strcasecmp(iobuf, request_GET) != 0) send_headers_and_exit(HTTP_NOT_IMPLEMENTED); - } #endif - *purl = ' '; + urlp = skip_whitespace(urlp); + if (urlp[0] != '/') + send_headers_and_exit(HTTP_BAD_REQUEST); - /* Copy URL from after "GET "/"POST " to stack-allocated char[] */ + /* Find end of URL and parse HTTP version, if any */ http_major_version = -1; - count = sscanf(purl, " %[^ ] HTTP/%d.%*d", iobuf, &http_major_version); - if (count < 1 || iobuf[0] != '/') { - /* Garbled request/URL */ - send_headers_and_exit(HTTP_BAD_REQUEST); - } - url = alloca(strlen(iobuf) + sizeof("/index.html")); - if (url == NULL) { - send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR); - } - strcpy(url, iobuf); + tptr = strchrnul(urlp, ' '); + /* Is it " HTTP/"? */ + if (tptr[0] && strncmp(tptr + 1, HTTP_200, 5) == 0) + http_major_version = (tptr[6] - '0'); + *tptr = '\0'; + + /* Copy URL from after "GET "/"POST " to stack-allocated char[] */ + urlcopy = alloca((tptr - urlp) + sizeof("/index.html")); + /*if (urlcopy == NULL) + * send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);*/ + strcpy(urlcopy, urlp); + /* NB: urlcopy ptr is never changed after this */ /* Extract url args if present */ - test = strchr(url, '?'); + tptr = strchr(urlcopy, '?'); g_query = NULL; - if (test) { - *test++ = '\0'; - g_query = test; + if (tptr) { + *tptr++ = '\0'; + g_query = tptr; } /* Decode URL escape sequences */ - test = decodeString(url, 0); - if (test == NULL) + tptr = decodeString(urlcopy, 0); + if (tptr == NULL) send_headers_and_exit(HTTP_BAD_REQUEST); - if (test == url + 1) { + if (tptr == urlcopy + 1) { /* '/' or NUL is encoded */ send_headers_and_exit(HTTP_NOT_FOUND); } @@ -1594,60 +1612,58 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr) /* Canonicalize path */ /* Algorithm stolen from libbb bb_simplify_path(), * but don't strdup and reducing trailing slash and protect out root */ - purl = test = url; + urlp = tptr = urlcopy; do { - if (*purl == '/') { + if (*urlp == '/') { /* skip duplicate (or initial) slash */ - if (*test == '/') { + if (*tptr == '/') { continue; } - if (*test == '.') { + if (*tptr == '.') { /* skip extra '.' */ - if (test[1] == '/' || !test[1]) { + if (tptr[1] == '/' || !tptr[1]) { continue; } /* '..': be careful */ - if (test[1] == '.' && (test[2] == '/' || !test[2])) { - ++test; - if (purl == url) { - /* protect root */ + if (tptr[1] == '.' && (tptr[2] == '/' || !tptr[2])) { + ++tptr; + if (urlp == urlcopy) /* protect root */ send_headers_and_exit(HTTP_BAD_REQUEST); - } - while (*--purl != '/') /* omit previous dir */; + while (*--urlp != '/') /* omit previous dir */; continue; } } } - *++purl = *test; - } while (*++test); - *++purl = '\0'; /* so keep last character */ - test = purl; /* end ptr */ + *++urlp = *tptr; + } while (*++tptr); + *++urlp = '\0'; /* so keep last character */ + tptr = urlp; /* end ptr */ /* If URL is a directory, add '/' */ - if (test[-1] != '/') { - if (is_directory(url + 1, 1, &sb)) { - found_moved_temporarily = url; + if (tptr[-1] != '/') { + if (is_directory(urlcopy + 1, 1, &sb)) { + found_moved_temporarily = urlcopy; } } /* Log it */ if (verbose > 1) - bb_error_msg("url:%s", url); + bb_error_msg("url:%s", urlcopy); - test = url; + tptr = urlcopy; ip_allowed = checkPermIP(); - while (ip_allowed && (test = strchr(test + 1, '/')) != NULL) { + while (ip_allowed && (tptr = strchr(tptr + 1, '/')) != NULL) { /* have path1/path2 */ - *test = '\0'; - if (is_directory(url + 1, 1, &sb)) { + *tptr = '\0'; + if (is_directory(urlcopy + 1, 1, &sb)) { /* may be having subdir config */ - parse_conf(url + 1, SUBDIR_PARSE); + parse_conf(urlcopy + 1, SUBDIR_PARSE); ip_allowed = checkPermIP(); } - *test = '/'; + *tptr = '/'; } if (http_major_version >= 0) { - /* Request was with "... HTTP/n.m", and n >= 0 */ + /* Request was with "... HTTP/nXXX", and n >= 0 */ /* Read until blank line for HTTP version specified, else parse immediate */ while (1) { @@ -1662,16 +1678,16 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr) if ((STRNCASECMP(iobuf, "Content-length:") == 0)) { /* extra read only for POST */ if (prequest != request_GET) { - test = iobuf + sizeof("Content-length:") - 1; - if (!test[0]) + tptr = iobuf + sizeof("Content-length:") - 1; + if (!tptr[0]) send_headers_and_exit(HTTP_BAD_REQUEST); errno = 0; /* not using strtoul: it ignores leading minus! */ - length = strtol(test, &test, 10); + length = strtol(tptr, &tptr, 10); /* length is "ulong", but we need to pass it to int later */ /* so we check for negative or too large values in one go: */ /* (long -> ulong conv caused negatives to be seen as > INT_MAX) */ - if (test[0] || errno || length > INT_MAX) + if (tptr[0] || errno || length > INT_MAX) send_headers_and_exit(HTTP_BAD_REQUEST); } } else if (STRNCASECMP(iobuf, "Cookie:") == 0) { @@ -1690,13 +1706,13 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr) * It shows up as "Authorization: Basic <userid:password>" where * the userid:password is base64 encoded. */ - test = skip_whitespace(iobuf + sizeof("Authorization:")-1); - if (STRNCASECMP(test, "Basic") != 0) + tptr = skip_whitespace(iobuf + sizeof("Authorization:")-1); + if (STRNCASECMP(tptr, "Basic") != 0) continue; - test += sizeof("Basic")-1; + tptr += sizeof("Basic")-1; /* decodeBase64() skips whitespace itself */ - decodeBase64(test); - credentials = checkPerm(url, test); + decodeBase64(tptr); + credentials = checkPerm(urlcopy, tptr); } #endif /* FEATURE_HTTPD_BASIC_AUTH */ } /* while extra header reading */ @@ -1705,13 +1721,13 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr) /* We read headers, disable peer timeout */ alarm(0); - if (strcmp(bb_basename(url), httpd_conf) == 0 || ip_allowed == 0) { + if (strcmp(bb_basename(urlcopy), httpd_conf) == 0 || ip_allowed == 0) { /* protect listing [/path]/httpd_conf or IP deny */ send_headers_and_exit(HTTP_FORBIDDEN); } #if ENABLE_FEATURE_HTTPD_BASIC_AUTH - if (credentials <= 0 && checkPerm(url, ":") == 0) { + if (credentials <= 0 && checkPerm(urlcopy, ":") == 0) { send_headers_and_exit(HTTP_UNAUTHORIZED); } #endif @@ -1720,24 +1736,24 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr) send_headers_and_exit(HTTP_MOVED_TEMPORARILY); } - test = url + 1; /* skip first '/' */ + tptr = urlcopy + 1; /* skip first '/' */ #if ENABLE_FEATURE_HTTPD_CGI - if (strncmp(test, "cgi-bin/", 8) == 0) { - if (test[8] == '\0') { + if (strncmp(tptr, "cgi-bin/", 8) == 0) { + if (tptr[8] == '\0') { /* protect listing "cgi-bin/" */ send_headers_and_exit(HTTP_FORBIDDEN); } - send_cgi_and_exit(url, prequest, length, cookie, content_type); + send_cgi_and_exit(urlcopy, prequest, length, cookie, content_type); } #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR { - char *suffix = strrchr(test, '.'); + char *suffix = strrchr(tptr, '.'); if (suffix) { Htaccess *cur; for (cur = script_i; cur; cur = cur->next) { if (strcmp(cur->before_colon + 1, suffix) == 0) { - send_cgi_and_exit(url, prequest, length, cookie, content_type); + send_cgi_and_exit(urlcopy, prequest, length, cookie, content_type); } } } @@ -1748,20 +1764,20 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr) } #endif /* FEATURE_HTTPD_CGI */ - if (purl[-1] == '/') - strcpy(purl, "index.html"); - if (stat(test, &sb) == 0) { + if (urlp[-1] == '/') + strcpy(urlp, "index.html"); + if (stat(tptr, &sb) == 0) { /* It's a dir URL and there is index.html */ ContentLength = sb.st_size; last_mod = sb.st_mtime; } #if ENABLE_FEATURE_HTTPD_CGI - else if (purl[-1] == '/') { + else if (urlp[-1] == '/') { /* It's a dir URL and there is no index.html * Try cgi-bin/index.cgi */ if (access("/cgi-bin/index.cgi"+1, X_OK) == 0) { - purl[0] = '\0'; - g_query = url; + urlp[0] = '\0'; + g_query = urlcopy; send_cgi_and_exit("/cgi-bin/index.cgi", prequest, length, cookie, content_type); } } @@ -1771,7 +1787,7 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr) * } */ - send_file_and_exit(test); + send_file_and_exit(tptr); #if 0 /* Is this needed? Why? */ if (DEBUG) |