tor-commits July 2012

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[stegotorus/master] git-svn-id: svn+ssh://spartan.csl.sri.com/svn/private/DEFIANCE@126 a58ff0ac-194c-e011-a152-003048836090
by zwol＠torproject.org 20 Jul '12

20 Jul '12

commit 5e617e61d1165df71237147dc60400c2b5f47ec5 Author: Vinod Yegneswaran <vinod(a)csl.sri.com> Date: Sun Nov 6 02:46:06 2011 +0000 git-svn-id: svn+ssh://spartan.csl.sri.com/svn/private/DEFIANCE@126 a58ff0ac-194c-e011-a152-003048836090 --- src/steg/payloads.c | 59 ++++++++++++++++++++++++++++++++++++++++---------- start-server.csh | 5 +--- 2 files changed, 48 insertions(+), 16 deletions(-) diff --git a/src/steg/payloads.c b/src/steg/payloads.c index 02be31b..c683f77 100644 --- a/src/steg/payloads.c +++ b/src/steg/payloads.c @@ -303,19 +303,7 @@ void gen_rfc_1123_date(char* buf, int buf_size) { -/* sample response header */ -/* - -HTTP/1.1 200 OK -Date: Fri, 21 Oct 2011 19:09:49 GMT -Server: Apache -Content-Length: 1441 -* Content-Encoding: gzip -Content-Type: text/html;charset=UTF-8 -* Keep-Alive: timeout=15, max=93 -Connection: close -*/ int gen_response_header(char* content_type, int gzip, int length, char* buf, int buflen) { @@ -501,6 +489,52 @@ unsigned int find_client_payload(char* buf, int len, int type) { * todo: * Use a more efficient regular expression matching algo */ + + + +int skipJSPattern(char *cp, int len) { + int i,j; + + char keywords [21][10]= {"function", "return", "var", "int", "random", "Math", "while", + "else", "for", "document", "write", "writeln", "true", + "false", "True", "False", "window", "indexOf", "navigator", "case", "if"}; + + if (len < 1) return 0; + + // change the limit to 21 to enable if as a keyword + for (i=0; i < 20; i++) { + char* word = keywords[i]; + + if (len <= (int) strlen(word)) + continue; + + if (word[0] != cp[0]) + continue; + + for (j=1; j < (int) strlen(word); j++) { + if (isxdigit(word[j])) { + if (!isxdigit(cp[j])) + goto next_word; + else + continue; + } + + if (cp[j] != word[j]) + goto next_word; + } + if (!isalnum(cp[j])) + return strlen(word)+1; + + next_word: + continue; + } + + return 0; +} + + +/* + int skipJSPattern (char *cp, int len) { // log_debug("Turning off skipJSPattern for debugging"); @@ -561,6 +595,7 @@ int skipJSPattern (char *cp, int len) { return 0; } +*/ int isalnum_ (char c) { diff --git a/start-server.csh b/start-server.csh index eb421c4..b7d61e6 100644 --- a/start-server.csh +++ b/start-server.csh @@ -2,8 +2,5 @@ setenv EVENT_NOKQUEUE yes # ./obfsproxy --log-min-severity=debug chop server 87.73.82.145:8080 127.0.0.1:8080 127.0.0.1:8081 # ./obfsproxy --log-min-severity=warn chop server 87.73.82.145:8080 127.0.0.1:8080 127.0.0.1:8081 -#./obfsproxy --log-min-severity=error chop server 87.73.82.145:8080 127.0.0.1:8080 127.0.0.1:8081 +./obfsproxy --log-min-severity=error chop server 87.73.82.145:8080 127.0.0.1:8080 127.0.0.1:8081 -# ./obfsproxy --log-min-severity=debug chop server 87.73.82.145:8080 128.18.9.71:8080 128.18.9.71:8081 -# ./obfsproxy --log-min-severity=warn chop server 87.73.82.145:8080 128.18.9.71:8080 128.18.9.71:8081 -./obfsproxy --log-min-severity=error chop server 87.73.82.145:8080 128.18.9.71:8080 128.18.9.71:8081

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[stegotorus/master] added gzip encoding to jsSteg
by zwol＠torproject.org 20 Jul '12

20 Jul '12

commit 2d5331fb2bd8b1197be8c7cb4fc43c7790102902 Author: Steven Cheung <cheung(a)csl.sri.com> Date: Thu Nov 3 00:11:21 2011 +0000 added gzip encoding to jsSteg git-svn-id: svn+ssh://spartan.csl.sri.com/svn/private/DEFIANCE@118 a58ff0ac-194c-e011-a152-003048836090 --- src/steg/jsSteg.c | 551 ++++++++++++++++++++++++--------------------------- src/steg/jsSteg.h | 15 ++- src/steg/payloads.c | 18 +- 3 files changed, 277 insertions(+), 307 deletions(-) diff --git a/src/steg/jsSteg.c b/src/steg/jsSteg.c index 9c67949..a323d44 100644 --- a/src/steg/jsSteg.c +++ b/src/steg/jsSteg.c @@ -32,6 +32,101 @@ int isxString(char *str) { /* + * isGzipContent(char *msg) + * + * If the HTTP header of msg specifies that the content is gzipped, + * this function returns 1; otherwise, it returns 0 + * + * Assumptions: + * msg is null terminated + * + */ +int isGzipContent (char *msg) { + char *ptr = msg, *end; + int gzipFlag = 0; + + if (!strstr(msg, "\r\n\r\n")) + return 0; + + while (1) { + end = strstr(ptr, "\r\n"); + if (end == NULL) { + break; + } + + if (!strncmp(ptr, "Content-Encoding: gzip", 22)) { + gzipFlag = 1; + break; + } + + if (!strncmp(end, "\r\n\r\n", 4)){ + break; + } + ptr = end+2; + } + + return gzipFlag; +} + + +/* + * findContentType(char *msg) + * + * If the HTTP header of msg specifies that the content type: + * case (content type) + * javascript: return HTTP_CONTENT_JAVASCRIPT + * pdf: return HTTP_CONTENT_PDF + * shockwave: return HTTP_CONTENT_SWF + * html: return HTTP_CONTENT_HTML + * otherwise: return 0 + * + * Assumptions: + * msg is null terminated + * + */ +int findContentType (char *msg) { + char *ptr = msg, *end; + + if (!strstr(msg, "\r\n\r\n")) + return 0; + + while (1) { + end = strstr(ptr, "\r\n"); + if (end == NULL) { + break; + } + + if (!strncmp(ptr, "Content-Type:", 13)) { + + if (!strncmp(ptr+14, "text/javascript", 15) || + !strncmp(ptr+14, "application/javascript", 22) || + !strncmp(ptr+14, "application/x-javascript", 24)) { + return HTTP_CONTENT_JAVASCRIPT; + } + if (!strncmp(ptr+14, "text/html", 9)) { + return HTTP_CONTENT_HTML; + } + if (!strncmp(ptr+14, "application/pdf", 15) || + !strncmp(ptr+14, "application/x-pdf", 17)) { + return HTTP_CONTENT_PDF; + } + if (!strncmp(ptr+14, "application/x-shockwave-flash", strlen("application/x-shockwave-flash"))) { + return HTTP_CONTENT_SWF; + } + } + + if (!strncmp(end, "\r\n\r\n", 4)){ + break; + } + ptr = end+2; + } + + return 0; +} + + + +/* * int encode(char *data, char *jTemplate, char *jData, * unsigned int dlen, unsigned int jtlen, unsigned int jdlen) * @@ -618,205 +713,175 @@ x_http2_server_JS_transmit (steg_t* s, struct evbuffer *source, conn_t *conn, un int nv; struct evbuffer *dest = conn_get_outbound(conn); size_t sbuflen = evbuffer_get_length(source); - char outbuf[HTTP_MSG_BUF_SIZE]; + char *hend, *jsTemplate = NULL, *outbuf, *outbuf2; char data[(int) sbuflen*2]; - unsigned int datalen; - char newHdr[MAX_RESP_HDR_SIZE]; - int newHdrLen = 0; - - size_t sofar = 0; - unsigned int cnt = 0; - int r; - - - - // by dynamically configuring the size returned by x_http2_transmit_room(), - // we can ensure that the size of data (source) is less than the max - // data length the JavaScript (jsTemplate) can encode - - - - // do { - int i; - unsigned int jsLen; - int mode; - char *hend; - unsigned int hLen; - unsigned int mjs = 0; - - char *jsTemplate = NULL; - int jsTemplateSize = 0; - - - - - /* int hdrLen; - int content_len; - int fin2; - - char* tmp; - char data2[20000]; - int decCnt; - */ - - datalen = 0; - - - log_debug("sbuflen = %d sofar = %d\n", (int) sbuflen, (int) sofar); - - - if (content_type != HTTP_CONTENT_JAVASCRIPT && - content_type != HTTP_CONTENT_HTML) { - log_warn("SERVER ERROR: Unknown content type (%d)", content_type); - return -1; - } - - // log_debug("SERVER: dumping data with length %d:", (int) sbuflen); - // evbuffer_dump(source, stderr); - // Convert data in 'source' to hexadecimal and write it to data - - nv = evbuffer_peek(source, sbuflen - sofar, NULL, NULL, 0); - iv = xzalloc(sizeof(struct evbuffer_iovec) * nv); - - if (evbuffer_peek(source, sbuflen - sofar, NULL, iv, nv) != nv) { - free(iv); - return -1; - } - - // jsTemplate should be init already, by x_http2_new or the previous invocation - // of this function - - if (content_type == HTTP_CONTENT_JAVASCRIPT) { - mjs = get_max_JS_capacity(); - } else if (content_type == HTTP_CONTENT_HTML) { - mjs = get_max_HTML_capacity(); - } - - if (mjs <= 0) { - log_warn("SERVER ERROR: No JavaScript found in jsTemplate"); - return -1; - } + unsigned int datalen = 0, cnt = 0, mjs = 0; + int r, i, mode, jsLen, hLen, cLen, newHdrLen = 0, outbuf2len; + + int gzipMode = JS_GZIP_RESP; - if (sbuflen > (size_t) mjs) { - log_warn("SERVER ERROR: (server_transmit) jsTemplate cannot accommodate data %d %dn", - (int) sbuflen, (int) mjs); - return -1; - } - - cnt = 0; + log_debug("sbuflen = %d\n", (int) sbuflen); - for (i = 0; i < nv; i++) { - const unsigned char *p = iv[i].iov_base; - const unsigned char *limit = p + iv[i].iov_len; - char c; + if (content_type != HTTP_CONTENT_JAVASCRIPT && + content_type != HTTP_CONTENT_HTML) { + log_warn("SERVER ERROR: Unknown content type (%d)", content_type); + return -1; + } - while (p < limit && cnt < sbuflen-sofar) { - c = *p++; - data[datalen] = "0123456789abcdef"[(c & 0xF0) >> 4]; - data[datalen+1] = "0123456789abcdef"[(c & 0x0F) >> 0]; - datalen += 2; - cnt++; - } - } + // log_debug("SERVER: dumping data with length %d:", (int) sbuflen); + // evbuffer_dump(source, stderr); - log_debug("SERVER encoded data in hex string (len %d):", datalen); - // buf_dump((unsigned char*)data, datalen, stderr); + nv = evbuffer_peek(source, sbuflen, NULL, NULL, 0); + iv = xzalloc(sizeof(struct evbuffer_iovec) * nv); + if (evbuffer_peek(source, sbuflen, NULL, iv, nv) != nv) { free(iv); + return -1; + } + if (content_type == HTTP_CONTENT_JAVASCRIPT) { + mjs = get_max_JS_capacity(); + } else if (content_type == HTTP_CONTENT_HTML) { + mjs = get_max_HTML_capacity(); + } + if (mjs <= 0) { + log_warn("SERVER ERROR: No JavaScript found in jsTemplate"); + return -1; + } - if (get_payload(content_type, datalen, &jsTemplate, &jsTemplateSize) == 1) { - log_debug("SERVER found the next HTTP response template with size %d", jsTemplateSize); - } else { - log_warn("SERVER couldn't find the next HTTP response template; reusing the previous one"); + if (sbuflen > (size_t) mjs) { + log_warn("SERVER ERROR: jsTemplate cannot accommodate data %d %dn", + (int) sbuflen, (int) mjs); + return -1; + } + + // Convert data in 'source' to hexadecimal and write it to data + cnt = 0; + for (i = 0; i < nv; i++) { + const unsigned char *p = iv[i].iov_base; + const unsigned char *limit = p + iv[i].iov_len; + char c; + + while (p < limit && cnt < sbuflen) { + c = *p++; + data[datalen] = "0123456789abcdef"[(c & 0xF0) >> 4]; + data[datalen+1] = "0123456789abcdef"[(c & 0x0F) >> 0]; + datalen += 2; + cnt++; } + } - log_debug("MJS %d %d", datalen, mjs); - + free(iv); + log_debug("SERVER encoded data in hex string (len %d):", datalen); + // buf_dump((unsigned char*)data, datalen, stderr); - if (jsTemplate == NULL) { - fprintf(stderr, "NO suitable payload found %d %d\n", datalen, mjs); - exit(-1); - } - // use encodeHTTPBody to embed data in the JS jsTemplate - // assumption: jsTemplate is null-terminated + if (get_payload(content_type, datalen, &jsTemplate, &jsLen) == 1) { + log_debug("SERVER found the applicable HTTP response template with size %d", jsLen); + } else { + log_warn("SERVER couldn't find the applicable HTTP response template"); + return -1; + } - log_debug("strlen(jsTemplate) = %d", (int)strlen(jsTemplate)); - log_debug("jsTemplateSize = %d", jsTemplateSize); - // unsigned int jsLen = strlen(jsTemplate); - jsLen = jsTemplateSize; + // log_debug("MJS %d %d", datalen, mjs); + if (jsTemplate == NULL) { + log_warn("NO suitable payload found %d %d", datalen, mjs); + return -1; + } + // assumption: jsTemplate is null-terminated + hend = strstr(jsTemplate, "\r\n\r\n"); + if (hend == NULL) { + log_warn("Unable to find end of header in the HTTP template"); + return -1; + } - mode = has_eligible_HTTP_content (jsTemplate, jsLen, HTTP_CONTENT_JAVASCRIPT); - hend = strstr(jsTemplate, "\r\n\r\n"); - if (hend == NULL) { - log_warn("Unable to find end of header in the HTTP template"); - return -1; - } + mode = has_eligible_HTTP_content (jsTemplate, jsLen, HTTP_CONTENT_JAVASCRIPT); - log_debug("SERVER: using HTTP resp template of length = %d\n", jsLen); - // log_debug("HTTP resp tempmlate:"); - // buf_dump((unsigned char*)jsTemplate, jsLen, stderr); + // log_debug("SERVER: using HTTP resp template of length = %d", jsLen); + // log_debug("HTTP resp tempmlate:"); + // buf_dump((unsigned char*)jsTemplate, jsLen, stderr); - hLen = hend+4-jsTemplate; - r = encodeHTTPBody(data, hend+4, outbuf, datalen, jsLen-hLen, HTTP_MSG_BUF_SIZE, mode); + hLen = hend+4-jsTemplate; + cLen = jsLen - hLen; + outbuf = malloc(cLen); + if (outbuf == NULL) { + log_warn("malloc for outbuf fails"); + return -1; + } - if (r < 0 || ((unsigned int) r < datalen)) { - fprintf(stderr, "incomplete data encoding\n"); - exit(-1); - log_debug("SERVER ERROR: Incomplete data encoding"); - return -1; - } + r = encodeHTTPBody(data, hend+4, outbuf, datalen, cLen, cLen, mode); - if (mode == CONTENT_JAVASCRIPT) { // JavaScript in HTTP body - newHdrLen = gen_response_header((char*) "application/x-javascript", 0, jsLen-hLen, newHdr, sizeof(newHdr)); - } else if (mode == CONTENT_HTML_JAVASCRIPT) { // JavaScript(s) embedded in HTML doc - newHdrLen = gen_response_header((char*) "text/html", 0, jsLen-hLen, newHdr, sizeof(newHdr)); - } else { // unknown mode - log_warn("SERVER ERROR: unknown mode for creating the HTTP response header"); - return -1; - } - if (newHdrLen < 0) { - log_warn("SERVER ERROR: gen_response_header fails for jsSteg"); - return -1; - } + if (r < 0 || ((unsigned int) r < datalen)) { + log_warn("SERVER ERROR: Incomplete data encoding"); + return -1; + } - if (evbuffer_add(dest, newHdr, newHdrLen)) { - log_warn("SERVER ERROR: evbuffer_add() fails for newHdr"); + // work in progress + if (gzipMode == 1) { + // conservative estimate: + // sizeof outbuf2 = cLen + 10-byte for gzip header + 8-byte for crc + outbuf2 = malloc(cLen+18); + if (outbuf2 == NULL) { + log_warn("malloc for outbuf2 fails"); return -1; } - // if (evbuffer_add(dest, jsTemplate, hLen)) { - // log_warn("SERVER ERROR: evbuffer_add() fails for jsTemplate"); - // return -1; - // } + outbuf2len = gzDeflate(outbuf, cLen, outbuf2, cLen+18, time(NULL)); - - if (evbuffer_add(dest, outbuf, jsLen-hLen)) { - log_warn("SERVER ERROR: evbuffer_add() fails for outbuf"); + if (outbuf2len <= 0) { + log_warn("gzDeflate for outbuf fails"); + free(outbuf2); return -1; } + free(outbuf); - sofar += datalen/2; - evbuffer_drain(source, datalen/2); - // } while (sbuflen > sofar); - + } else { + outbuf2 = outbuf; + outbuf2len = cLen; + } - // fprintf(stderr, "SERVER TRANSMITTED payload of size %d\n", (int) sbuflen); + // outbuf2 points to the HTTP payload (of length outbuf2len) to be sent + + if (mode == CONTENT_JAVASCRIPT) { // JavaScript in HTTP body + newHdrLen = gen_response_header((char*) "application/x-javascript", gzipMode, + outbuf2len, newHdr, sizeof(newHdr)); + } else if (mode == CONTENT_HTML_JAVASCRIPT) { // JavaScript(s) embedded in HTML doc + newHdrLen = gen_response_header((char*) "text/html", gzipMode, + outbuf2len, newHdr, sizeof(newHdr)); + } else { // unknown mode + log_warn("SERVER ERROR: unknown mode for creating the HTTP response header"); + free(outbuf2); + return -1; + } + if (newHdrLen < 0) { + log_warn("SERVER ERROR: gen_response_header fails for jsSteg"); + free(outbuf2); + return -1; + } - // obtain a usable HTTP response template for the next data, and - // modify jsTemplateCapacity + // newHdr points to the HTTP header (of length newHdrLen) to be sent + if (evbuffer_add(dest, newHdr, newHdrLen)) { + log_warn("SERVER ERROR: evbuffer_add() fails for newHdr"); + free(outbuf2); + return -1; + } - log_debug("SERVER finding the next HTTP response template"); + if (evbuffer_add(dest, outbuf2, outbuf2len)) { + log_warn("SERVER ERROR: evbuffer_add() fails for outbuf2"); + free(outbuf2); + return -1; + } + evbuffer_drain(source, sbuflen); + free(outbuf2); conn_close_after_transmit(conn); // downcast_steg(s)->have_transmitted = 1; return 0; @@ -836,17 +901,14 @@ x_http2_handle_client_JS_receive(steg_t *s, conn_t *conn, struct evbuffer *dest, char buf[10]; char respMsg[HTTP_MSG_BUF_SIZE]; char data[HTTP_MSG_BUF_SIZE]; + char buf2[HTTP_MSG_BUF_SIZE]; - unsigned char *field; - unsigned char *fieldStart; - unsigned char* fieldEnd; - unsigned char *fieldValStart; + unsigned char *field, *fieldStart, *fieldEnd, *fieldValStart; char *httpBody; + int decCnt, fin, i, j, k, gzipMode=0, httpBodyLen, buf2len, contentType = 0; ev_ssize_t r; - int mode, decCnt, fin; struct evbuffer * scratch; - int i,j,k; char c; @@ -897,9 +959,7 @@ x_http2_handle_client_JS_receive(steg_t *s, conn_t *conn, struct evbuffer *dest, if (response_len > evbuffer_get_length(source)) return RECV_INCOMPLETE; - - - + // read the entire HTTP resp if (response_len < HTTP_MSG_BUF_SIZE) { r = evbuffer_copyout(source, respMsg, response_len); @@ -921,21 +981,37 @@ x_http2_handle_client_JS_receive(steg_t *s, conn_t *conn, struct evbuffer *dest, log_debug("CLIENT received HTTP response with length %d\n", response_len); // buf_dump((unsigned char*)respMsg, response_len, stderr); // log_debug("HTTP response header:"); - // buf_dump((unsigned char*)respMsg, hdrLen, stderr); - - httpBody = respMsg + hdrLen; - - log_debug("CLIENT Before has_eligible HTTP content\n"); - // find out if the resp is a JavaScript or JS embedded in HTML doc - mode = has_eligible_HTTP_content (respMsg, response_len, HTTP_CONTENT_JAVASCRIPT); - if (mode != 1 && mode != 2) { - log_debug("CLIENT ERROR: HTTP response not useful for jsSteg (mode %d)", mode); + // buf_dump((unsigned char*)respMsg, hdrLen+80, stderr); + + contentType = findContentType (respMsg); + if (contentType != HTTP_CONTENT_JAVASCRIPT && contentType != HTTP_CONTENT_HTML) { + log_warn("ERROR: Invalid content type (%d)", contentType); return RECV_BAD; } - log_debug("CLIENT Before decodeHTTPBody; mode: %d\n", mode); - - decCnt = decodeHTTPBody(httpBody, data, response_len-hdrLen, HTTP_MSG_BUF_SIZE, &fin, mode); + httpBody = respMsg + hdrLen; + httpBodyLen = response_len - hdrLen; + + gzipMode = isGzipContent(respMsg); + if (gzipMode) { + log_debug("gzip content encoding detected"); + buf2len = gzInflate(httpBody, httpBodyLen, buf2, HTTP_MSG_BUF_SIZE); + if (buf2len <= 0) { + log_warn("gzInflate for httpBody fails"); + return RECV_BAD; + } + buf2[buf2len] = 0; + httpBody = buf2; + httpBodyLen = buf2len; + } + + if (contentType == HTTP_CONTENT_JAVASCRIPT) { + decCnt = decodeHTTPBody(httpBody, data, httpBodyLen, HTTP_MSG_BUF_SIZE, + &fin, CONTENT_JAVASCRIPT); + } else { + decCnt = decodeHTTPBody(httpBody, data, httpBodyLen, HTTP_MSG_BUF_SIZE, + &fin, CONTENT_HTML_JAVASCRIPT); + } data[decCnt] = 0; log_debug("After decodeHTTPBody; decCnt: %d\n", decCnt); @@ -1011,119 +1087,6 @@ x_http2_handle_client_JS_receive(steg_t *s, conn_t *conn, struct evbuffer *dest, } - -//int -//x_http2_handle_server_JS_receive(steg_t *s, conn_t *conn, struct evbuffer *dest, struct evbuffer* source) { -// -// int cnt = 0; -// -// do { -// struct evbuffer_ptr s2 = evbuffer_search(source, "\r\n\r\n", sizeof ("\r\n\r\n") -1 , NULL); -// unsigned char* data; -// unsigned char* limit; -// unsigned char *p; -// int unwrapped_cookie_len; -// struct evbuffer *scratch; -// unsigned char c, h, secondhalf; -// unsigned char buf[evbuffer_get_length(source)]; -// -// -// if (s2.pos == -1) { -// log_debug("Did not find end of request %d", (int) evbuffer_get_length(source)); -// // evbuffer_dump(source, stderr); -// return RECV_INCOMPLETE; -// } -// -// log_debug("SERVER received request header of length %d", (int)s2.pos); -// -// data = evbuffer_pullup(source, s2.pos); -// if (data == NULL) { -// log_debug("SERVER evbuffer_pullup fails"); -// return RECV_BAD; -// } -// -// limit = data + s2.pos; -// -// data = (unsigned char*) strstr((char*) data, "Cookie:"); -// -// if (data == NULL || memcmp(data, "Cookie:", sizeof "Cookie:"-1)) { -// log_debug("Unexpected HTTP verb: %.*s", 5, data); -// return RECV_BAD; -// } -// -// p = data + sizeof "Cookie: "-1; -// unwrapped_cookie_len = unwrap_cookie(p, buf, (int) (limit - p)); -// -// log_debug("SERVER: received cookie of length = %d %d\n", unwrapped_cookie_len, (int) (limit-p)); -// // buf_dump(buf, unwrapped_cookie_len, stderr); -// // fprintf(stderr, "==========================\n"); -// // buf_dump(p, (int) (limit-p), stderr); -// -// -// // log_debug("hello SERVER received %d cnt = %d\n", (int) (limit - p), cnt); -// // buf_dump(p, (int) (limit-p), stderr); -// -// /* We need a scratch buffer here because the contract is that if -// we hit a decode error we *don't* write anything to 'dest'. */ -// scratch = evbuffer_new(); -// -// if (!scratch) return RECV_BAD; -// -// -// if (evbuffer_expand(scratch, unwrapped_cookie_len/2)) { -// log_debug("Evbuffer expand failed \n"); -// evbuffer_free(scratch); -// return RECV_BAD; -// } -// p = buf; -// -// -// secondhalf = 0; -// while ((int) (p - buf) < unwrapped_cookie_len) { -// if (!secondhalf) c = 0; -// if ('0' <= *p && *p <= '9') h = *p - '0'; -// else if ('a' <= *p && *p <= 'f') h = *p - 'a' + 10; -// else if ('A' <= *p && *p <= 'F') h = *p - 'A' + 10; -// else if (*p == '=' && !secondhalf) { -// p++; -// continue; -// } else { -// evbuffer_free(scratch); -// log_debug("Decode error: unexpected URI characterasdfaf %d", *p); -// return RECV_BAD; -// } -// -// c = (c << 4) + h; -// if (secondhalf) { -// evbuffer_add(scratch, &c, 1); -// // log_debug("adding to scratch"); -// cnt++; -// } -// secondhalf = !secondhalf; -// p++; -// } -// -// -// -// if (evbuffer_add_buffer(dest, scratch)) { -// evbuffer_free(scratch); -// log_debug("Failed to transfer buffer"); -// return RECV_BAD; -// } -// evbuffer_drain(source, s2.pos + sizeof("\r\n\r\n") - 1); -// evbuffer_free(scratch); -// } while (evbuffer_get_length(source)); -// -// -// log_debug("SERVER RECEIVED payload %d\n", cnt); -// // downcast_steg(s)->have_received = 1; -// conn_transmit_soon(conn, 100); -// return RECV_GOOD; -//} - - - - /***** int main() { diff --git a/src/steg/jsSteg.h b/src/steg/jsSteg.h index c076460..949aa25 100644 --- a/src/steg/jsSteg.h +++ b/src/steg/jsSteg.h @@ -9,23 +9,32 @@ #include "connections.h" #include "steg.h" #include <event2/buffer.h> +#include "zpack.h" - -/* error codes */ +// error codes #define INVALID_BUF_SIZE -1 #define INVALID_DATA_CHAR -2 +// controlling content gzipping for jsSteg +#define JS_GZIP_RESP 1 + int encodeHTTPBody(char *data, char *jTemplate, char *jData,unsigned int dlen, unsigned int jtlen, unsigned int jdlen, int mode); + int isxString(char *str); + +int isGzipContent (char *msg); + +int findContentType (char *msg); + int decodeHTTPBody (char *jData, char *dataBuf, unsigned int jdlen, unsigned int dataBufSize, int *fin, int mode); int encode(char *data, char *jTemplate, char *jData, unsigned int dlen, unsigned int jtlen, unsigned int jdlen ); -int encode2(char *data, char *jTemplate, char *jData, +int encode2(char *data, char *jTemplate, char *jData, unsigned int dlen, unsigned int jtlen, unsigned int jdlen, int *fin); diff --git a/src/steg/payloads.c b/src/steg/payloads.c index 017c469..02be31b 100644 --- a/src/steg/payloads.c +++ b/src/steg/payloads.c @@ -865,7 +865,7 @@ strInBinary (const char *pattern, unsigned int patternLen, int has_eligible_HTTP_content (char* buf, int len, int type) { char* ptr = buf; char* matchptr; - int tjFlag=0, thFlag=0, ceFlag=0, teFlag=0, http304Flag=0, clZeroFlag=0, pdfFlag=0, swfFlag=0; + int tjFlag=0, thFlag=0, ceFlag=0, teFlag=0, http304Flag=0, clZeroFlag=0, pdfFlag=0, swfFlag=0, gzipFlag=0; char* end, *cp; #ifdef DEBUG @@ -906,7 +906,9 @@ int has_eligible_HTTP_content (char* buf, int len, int type) { swfFlag = 1; } - } else if (!strncmp(ptr, "Content-Encoding:", 17)) { + } else if (!strncmp(ptr, "Content-Encoding: gzip", 22)) { + gzipFlag = 1; + } else if (!strncmp(ptr, "Content-Encoding:", 17)) { // Content-Encoding that is not gzip ceFlag = 1; } else if (!strncmp(ptr, "Transfer-Encoding:", 18)) { teFlag = 1; @@ -923,8 +925,8 @@ int has_eligible_HTTP_content (char* buf, int len, int type) { } #ifdef DEBUG - printf("tjFlag=%d; thFlag=%d; ceFlag=%d; teFlag=%d; http304Flag=%d; clZeroFlag=%d\n", - tjFlag, thFlag, ceFlag, teFlag, http304Flag, clZeroFlag); + printf("tjFlag=%d; thFlag=%d; gzipFlag=%d; ceFlag=%d; teFlag=%d; http304Flag=%d; clZeroFlag=%d\n", + tjFlag, thFlag, gzipFlag, ceFlag, teFlag, http304Flag, clZeroFlag); #endif // if (type == HTTP_CONTENT_JAVASCRIPT) @@ -933,12 +935,9 @@ int has_eligible_HTTP_content (char* buf, int len, int type) { if (http304Flag || clZeroFlag) return 0; // for now, we're not dealing with Transfer-Encoding (e.g., chunked) + // or Content-Encoding that is not gzip // if (teFlag) return 0; - // if (ceFlag) return 0; // for now, we remove "Content-Encoding: gzip" in fixContentLen if (teFlag || ceFlag) return 0; -/***** - if (teFlag) return 0; - *****/ if (tjFlag && ceFlag && end != NULL) { log_debug("(JS) gzip flag detected with hdr len %d", (int)(end-buf+4)); @@ -963,9 +962,8 @@ int has_eligible_HTTP_content (char* buf, int len, int type) { if (http304Flag || clZeroFlag) return 0; // for now, we're not dealing with Transfer-Encoding (e.g., chunked) - // or Content-Encoding (e.g., gzip) + // or Content-Encoding that is not gzip // if (teFlag) return 0; - // if (ceFlag) return 0; if (teFlag || ceFlag) return 0; // check if HTTP body contains "endstream";

1 0

[stegotorus/master] git-svn-id: svn+ssh://spartan.csl.sri.com/svn/private/DEFIANCE@129 a58ff0ac-194c-e011-a152-003048836090
by zwol＠torproject.org 20 Jul '12

20 Jul '12

commit 8afedcde7390e7515f35dd07f84af91015aa0b7e Author: Vinod Yegneswaran <vinod(a)csl.sri.com> Date: Mon Nov 7 20:35:29 2011 +0000 git-svn-id: svn+ssh://spartan.csl.sri.com/svn/private/DEFIANCE@129 a58ff0ac-194c-e011-a152-003048836090 --- src/steg/payloads.c | 152 ++++++++++++--------------------------------------- src/steg/payloads.h | 1 - 2 files changed, 36 insertions(+), 117 deletions(-) diff --git a/src/steg/payloads.c b/src/steg/payloads.c index 0cae234..a3e2f65 100644 --- a/src/steg/payloads.c +++ b/src/steg/payloads.c @@ -546,48 +546,51 @@ unsigned int find_client_payload(char* buf, int len, int type) { -int skipJSPattern(char *cp, int len) { - int i,j; +/* int skipJSPattern(char *cp, int len) { */ +/* int i,j; */ - char keywords [21][10]= {"function", "return", "var", "int", "random", "Math", "while", - "else", "for", "document", "write", "writeln", "true", - "false", "True", "False", "window", "indexOf", "navigator", "case", "if"}; - if (len < 1) return 0; +/* char keywords [21][10]= {"function", "return", "var", "int", "random", "Math", "while", */ +/* "else", "for", "document", "write", "writeln", "true", */ +/* "false", "True", "False", "window", "indexOf", "navigator", "case", "if"}; */ - // change the limit to 21 to enable if as a keyword - for (i=0; i < 20; i++) { - char* word = keywords[i]; - - if (len <= (int) strlen(word)) - continue; - if (word[0] != cp[0]) - continue; +/* return 0; */ +/* if (len < 1) return 0; */ - for (j=1; j < (int) strlen(word); j++) { - if (isxdigit(word[j])) { - if (!isxdigit(cp[j])) - goto next_word; - else - continue; - } +/* // change the limit to 21 to enable if as a keyword */ +/* for (i=0; i < 20; i++) { */ +/* char* word = keywords[i]; */ + +/* if (len <= (int) strlen(word)) */ +/* continue; */ + +/* if (word[0] != cp[0]) */ +/* continue; */ + +/* for (j=1; j < (int) strlen(word); j++) { */ +/* if (isxdigit(word[j])) { */ +/* if (!isxdigit(cp[j])) */ +/* goto next_word; */ +/* else */ +/* continue; */ +/* } */ - if (cp[j] != word[j]) - goto next_word; - } - if (!isalnum(cp[j])) - return strlen(word)+1; +/* if (cp[j] != word[j]) */ +/* goto next_word; */ +/* } */ +/* if (!isalnum(cp[j])) */ +/* return strlen(word)+1; */ - next_word: - continue; - } +/* next_word: */ +/* continue; */ +/* } */ + +/* return 0; */ +/* } */ - return 0; -} -/* int skipJSPattern (char *cp, int len) { @@ -649,7 +652,7 @@ int skipJSPattern (char *cp, int len) { return 0; } -*/ + int isalnum_ (char c) { @@ -753,89 +756,6 @@ int offset2Hex (char *p, int range, int isLastCharHex) { } /* - * capacityJS returns the number of usable hex char - * in the input HTTP message for data encoding - * - * Input: - * buf - pointer to HTTP message - * len - sizeof buf - * mode - - * CONTENT_JAVASCRIPT (case 1); HTTP message body is a JavaScript - * (e.g., Content-Type: {text/javascript, application/x-javascript, - * application/javascript}) - * CONTENT_HTML_JAVASCRIPT (case 2) - * Content-Type: text/html and HTTP message body contains - * <script type="text/javascript"> ... </script> - * - * Output: - * capacityJS returns the number of usable hex char that can be embedded - * in the HTTP message - * - * Note: - * This is a prototype for the simple version (all hex char are usable) - * will refine this to skip JavaScript keywords in the next iteration - * - */ - - - -unsigned int capacityJS (char* buf, int len, int mode) { - char *hEnd, *bp, *jsStart, *jsEnd; - int cnt=0; - - // jump to the beginning of the body of the HTTP message - hEnd = strstr(buf, "\r\n\r\n"); - if (hEnd == NULL) { - // cannot find the separator between HTTP header and HTTP body - return 0; - } - bp = hEnd + 4; - - if (mode == CONTENT_JAVASCRIPT) { - while (bp < (buf+len)) { - if (isxdigit(*bp)) { - cnt++; -#ifdef DEBUG - printf("%c", *bp); -#endif - } - bp++; - } -#ifdef DEBUG - printf("\n"); -#endif - return cnt; - } else if (mode == CONTENT_HTML_JAVASCRIPT) { - while (bp < (buf+len)) { - jsStart = strstr(bp, "<script type=\"text/javascript\">"); - if (jsStart == NULL) break; - bp = jsStart+31; - jsEnd = strstr(bp, "</script>"); - if (jsEnd == NULL) break; - // count the number of usable hex char between jsStart+31 and jsEnd - while (bp < jsEnd) { - if (isxdigit(*bp)) { - cnt++; -#ifdef DEBUG - printf("%c", *bp); -#endif - } - bp++; - } - bp += 9; - } -#ifdef DEBUG - printf("\n"); -#endif - return cnt; - } else { - fprintf(stderr, "Unknown mode (%d) for capacityJS() ... \n", mode); - return 0; - } - -} - -/* * capacityJS3 is the next iteration for capacityJS */ unsigned int capacityJS3 (char* buf, int len, int mode) { diff --git a/src/steg/payloads.h b/src/steg/payloads.h index 56729fe..7d66bbf 100644 --- a/src/steg/payloads.h +++ b/src/steg/payloads.h @@ -143,7 +143,6 @@ int skipJSPattern (char *cp, int len); int isalnum_ (char c); int offset2Alnum_ (char *p, int range); int offset2Hex (char *p, int range, int isLastCharHex); -unsigned int capacityJS (char* buf, int len, int mode); unsigned int capacityJS3 (char* buf, int len, int mode); unsigned int get_max_JS_capacity(void); unsigned int get_max_HTML_capacity(void);

1 0

[stegotorus/master] fixed pdfSteg so that client no longer receives an extra char
by zwol＠torproject.org 20 Jul '12

20 Jul '12

commit 9a9cde1295e9ea0855e6227898542ffdfce71743 Author: Steven Cheung <cheung(a)csl.sri.com> Date: Mon Nov 7 21:05:37 2011 +0000 fixed pdfSteg so that client no longer receives an extra char git-svn-id: svn+ssh://spartan.csl.sri.com/svn/private/DEFIANCE@130 a58ff0ac-194c-e011-a152-003048836090 --- src/steg/pdfSteg.c | 8 +------- 1 files changed, 1 insertions(+), 7 deletions(-) diff --git a/src/steg/pdfSteg.c b/src/steg/pdfSteg.c index 4a91e55..81efdf4 100644 --- a/src/steg/pdfSteg.c +++ b/src/steg/pdfSteg.c @@ -126,7 +126,7 @@ removeDelimiter(char *inbuf, int inbuflen, char *outbuf, int outbuflen, outbuf[cnt++] = delimiter1; ibp++; } else { // end-of-data pattern detected *endFlag = 1; - break; + return cnt; } } } @@ -490,12 +490,6 @@ x_http2_handle_client_PDF_receive(steg_t *s, conn_t *conn, struct evbuffer *dest log_debug("CLIENT unwrapped data of length %d:", outbuflen); - // debugging - // buf_dump((unsigned char *)outbuf, outbuflen, stderr); - // ***** not sure why there is an extra char at the end of outbuf - outbuflen--; - - if (evbuffer_add(dest, outbuf, outbuflen)) { log_warn("CLIENT ERROR: evbuffer_add to dest fails\n"); return RECV_BAD;

1 0

[stegotorus/master] Linda's README for compiling obfsproxy on various platforms
by zwol＠torproject.org 20 Jul '12

20 Jul '12

commit 1640842c048a05206144303f0f6df389ab79d711 Author: Linda Briesemeister <linda.briesemeister(a)sri.com> Date: Fri Nov 11 16:21:40 2011 +0000 Linda's README for compiling obfsproxy on various platforms git-svn-id: svn+ssh://spartan.csl.sri.com/svn/private/DEFIANCE@138 a58ff0ac-194c-e011-a152-003048836090 --- README.Linda | 69 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 69 insertions(+), 0 deletions(-) diff --git a/README.Linda b/README.Linda new file mode 100644 index 0000000..2ecaa3c --- /dev/null +++ b/README.Linda @@ -0,0 +1,69 @@ +compiling obfsproxy on Mac OS X 10.6 +==================================== + +0) prelims + + a) autoconf 2.68 + +cd ~/src/autoconf-2.68 +./configure --prefix=/usr && make +make check # takes a long, long time! +sudo make install + + b) automake 1.11 + +cd ~/src/automake-1.11.1 +./configure --prefix=/usr && make +sudo make install + +1) obfsproxy + +cd ~/src/DEFIANCE/code/obfsproxy +./autogen.sh +./configure +make + + +compiling obfsproxy under Ubuntu 11.10 +====================================== + +in source directory: + +[ in file Makefile.am: add "-Wno-error=format" at the end of WARNINGS variable; remove "-Werror" & save ] + +$> ./autogen.sh +$> ./configure +[…] +configure: error: Package requirements (libcrypto >= 0.9.7) were not met: + +No package 'libcrypto' found +[…] +$> sudo find / -name openssl.pc +/usr/lib/i386-linux-gnu/pkgconfig/openssl.pc +$> echo $PKG_CONFIG_PATH + +$> export PKG_CONFIG_PATH=/usr/lib/i386-linux-gnu/pkgconfig +$> ./configure +$> make + + +compiling obfsproxy under Ubuntu 10.04 (DETERlab) +================================================= + +create local disk space: + +$> sudo /usr/local/etc/emulab/mkextrafs.pl /mnt + +copy source code there to compile: + +$> sudo mkdir /mnt/local/alice +$> sudo chown linda:SAF-DEFIANCE /mnt/local/alice +$> cd /mnt/local/alice +$> tar -xzvf ~/src/obfsproxy-3.2.tar.gz +$> cd obfsproxy-3.2 +$> make clean # without this it will complain about some protocols not found! +$> emacs Makefile.am +[ add "-Wno-error=format" at the end of WARNINGS variable; remove "-Werror" & save & exit ] +$> ./autogen.sh +$> ./configure +$> make

1 0

[stegotorus/master] fixed bug in http2_server_receive.
by zwol＠torproject.org 20 Jul '12

20 Jul '12

commit c47a57efb1859b12c83d1d59215021cbb73e2f04 Author: Vinod Yegneswaran <vinod(a)csl.sri.com> Date: Fri Nov 11 19:34:57 2011 +0000 fixed bug in http2_server_receive. git-svn-id: svn+ssh://spartan.csl.sri.com/svn/private/DEFIANCE@139 a58ff0ac-194c-e011-a152-003048836090 --- src/steg/x_http2.c | 7 ++----- 1 files changed, 2 insertions(+), 5 deletions(-) diff --git a/src/steg/x_http2.c b/src/steg/x_http2.c index a1bc100..e714305 100644 --- a/src/steg/x_http2.c +++ b/src/steg/x_http2.c @@ -723,7 +723,6 @@ x_http2_server_receive(steg_t *s, conn_t *conn, struct evbuffer *dest, struct ev do { struct evbuffer_ptr s2 = evbuffer_search(source, "\r\n\r\n", sizeof ("\r\n\r\n") -1 , NULL); - unsigned char* limit; unsigned char *p; unsigned char c, h, secondhalf; char outbuf[MAX_COOKIE_SIZE]; @@ -749,12 +748,10 @@ x_http2_server_receive(steg_t *s, conn_t *conn, struct evbuffer *dest, struct ev data[s2.pos+3] = 0; - limit = data + s2.pos; - type = find_uri_type((char *)data, s2.pos+4); if (strstr((char*) data, "Cookie") != NULL) { - p = (unsigned char*) strstr((char*) data, "Cookie:") + + sizeof "Cookie: "-1; + p = (unsigned char*) strstr((char*) data, "Cookie:") + sizeof "Cookie: "-1; cookie_mode = 1; } else @@ -765,7 +762,7 @@ x_http2_server_receive(steg_t *s, conn_t *conn, struct evbuffer *dest, struct ev c = 0; - while (strncmp((char*) p, "\r\n", 4) != 0 && (cookie_mode != 0 || p[0] != '.')) { + while (strncmp((char*) p, "\r\n", 2) != 0 && (cookie_mode != 0 || p[0] != '.')) { if (!secondhalf) c = 0; if ('0' <= *p && *p <= '9')

1 0

[stegotorus/master] git-svn-id: svn+ssh://spartan.csl.sri.com/svn/private/DEFIANCE@137 a58ff0ac-194c-e011-a152-003048836090
by zwol＠torproject.org 20 Jul '12

20 Jul '12

commit bc7435272a84dec0a3c865acf95fffb57e661c7b Author: Vinod Yegneswaran <vinod(a)csl.sri.com> Date: Fri Nov 11 05:20:14 2011 +0000 git-svn-id: svn+ssh://spartan.csl.sri.com/svn/private/DEFIANCE@137 a58ff0ac-194c-e011-a152-003048836090 --- src/steg/payloads.c | 241 ++++++++++++++++++++++++++++---------------------- src/steg/payloads.h | 2 +- src/steg/x_http.c | 2 +- src/steg/x_http2.c | 30 ++++--- 4 files changed, 153 insertions(+), 122 deletions(-) diff --git a/src/steg/payloads.c b/src/steg/payloads.c index a3e2f65..76bb213 100644 --- a/src/steg/payloads.c +++ b/src/steg/payloads.c @@ -387,28 +387,46 @@ int parse_client_headers(char* inbuf, char* outbuf, int len) { int -find_uri_type(char* buf) { +find_uri_type(char* buf_orig, int buflen) { char* uri; - int uri_len; char* ext; - if (strncmp(buf, "GET", 3) != 0 && strncmp(buf, "POST", 4) != 0) - return -1; + char* buf = malloc(buflen+1); + char* uri_end; + + + memcpy(buf, buf_orig, buflen); + buf[buflen] = 0; - buf = strchr(buf, ' ') + 1; - uri_len = strchr(buf, ' ') - buf; - if (uri_len < 0) { - fprintf(stderr, "buf = %sabc\n", buf); - exit (-1); + if (strncmp(buf, "GET", 3) != 0 + && strncmp(buf, "POST", 4) != 0) { + fprintf(stderr, "HERE %s\n", buf); + return -1; + } + + + + uri = strchr(buf, ' ') + 1; + if (uri == NULL) { + fprintf(stderr, "Invalid URL\n"); + return -1; } - uri = malloc(uri_len + 1); + uri_end = strchr(uri, ' '); + + if (uri_end == NULL) { + fprintf(stderr, "unterminated uri\n"); + return -1; + } + + uri_end[0] = 0; + + + - strncpy(uri, buf, uri_len); - uri[uri_len] = 0; ext = strrchr(uri, '/'); @@ -435,6 +453,9 @@ find_uri_type(char* buf) { if (!strncmp(ext, ".swf", 4) || !strncmp(ext, ".SWF", 4)) return HTTP_CONTENT_SWF; + + + free(buf); return -1; } @@ -503,9 +524,9 @@ unsigned int find_client_payload(char* buf, int len, int type) { pentry_header* p = &payload_hdrs[r]; if (p->ptype == type) { inbuf = payloads[r]; - if (find_uri_type(inbuf) != HTTP_CONTENT_SWF && - find_uri_type(inbuf) != HTTP_CONTENT_HTML && - find_uri_type(inbuf) != HTTP_CONTENT_JAVASCRIPT) { + if (find_uri_type(inbuf, p->length) != HTTP_CONTENT_SWF && + find_uri_type(inbuf, p->length) != HTTP_CONTENT_HTML && + find_uri_type(inbuf, p->length) != HTTP_CONTENT_JAVASCRIPT) { goto next; } if (p->length > len) { @@ -546,112 +567,111 @@ unsigned int find_client_payload(char* buf, int len, int type) { -/* int skipJSPattern(char *cp, int len) { */ -/* int i,j; */ +int skipJSPattern(char *cp, int len) { + int i,j; -/* char keywords [21][10]= {"function", "return", "var", "int", "random", "Math", "while", */ -/* "else", "for", "document", "write", "writeln", "true", */ -/* "false", "True", "False", "window", "indexOf", "navigator", "case", "if"}; */ + char keywords [21][10]= {"function", "return", "var", "int", "random", "Math", "while", + "else", "for", "document", "write", "writeln", "true", + "false", "True", "False", "window", "indexOf", "navigator", "case", "if"}; -/* return 0; */ -/* if (len < 1) return 0; */ + if (len < 1) return 0; -/* // change the limit to 21 to enable if as a keyword */ -/* for (i=0; i < 20; i++) { */ -/* char* word = keywords[i]; */ + // change the limit to 21 to enable if as a keyword + for (i=0; i < 20; i++) { + char* word = keywords[i]; -/* if (len <= (int) strlen(word)) */ -/* continue; */ - -/* if (word[0] != cp[0]) */ -/* continue; */ - -/* for (j=1; j < (int) strlen(word); j++) { */ -/* if (isxdigit(word[j])) { */ -/* if (!isxdigit(cp[j])) */ -/* goto next_word; */ -/* else */ -/* continue; */ -/* } */ + if (len <= (int) strlen(word)) + continue; + + if (word[0] != cp[0]) + continue; + + for (j=1; j < (int) strlen(word); j++) { + if (isxdigit(word[j])) { + if (!isxdigit(cp[j])) + goto next_word; + else + continue; + } -/* if (cp[j] != word[j]) */ -/* goto next_word; */ -/* } */ -/* if (!isalnum(cp[j])) */ -/* return strlen(word)+1; */ + if (cp[j] != word[j]) + goto next_word; + } + if (!isalnum(cp[j])) + return strlen(word)+1; -/* next_word: */ -/* continue; */ -/* } */ + next_word: + continue; + } -/* return 0; */ -/* } */ + return 0; +} -int skipJSPattern (char *cp, int len) { +/* int skipJSPattern (char *cp, int len) { */ - // log_debug("Turning off skipJSPattern for debugging"); - // return 0; +/* // log_debug("Turning off skipJSPattern for debugging"); */ +/* // return 0; */ - if (len < 1) return 0; +/* if (len < 1) return 0; */ - if (len > 8) { - // "function " and "function(" - if (cp[0] == 'f' && - !strncmp(cp+1, "un", 2) && - isxdigit(cp[3]) && - !strncmp(cp+4, "tion", 4) && - (cp[8] == ' ' || cp[8] == '(')) - return 9; - } +/* if (len > 8) { */ +/* // "function " and "function(" */ +/* if (cp[0] == 'f' && */ +/* !strncmp(cp+1, "un", 2) && */ +/* isxdigit(cp[3]) && */ +/* !strncmp(cp+4, "tion", 4) && */ +/* (cp[8] == ' ' || cp[8] == '(')) */ +/* return 9; */ +/* } */ - if (len > 6) { - // "return " - if (cp[0] == 'r' && - isxdigit(cp[1]) && - !strncmp(cp+2, "turn ", 5)) - return 7; - // "switch " - if (cp[0] == 's' && - !strncmp(cp+1, "wit", 3) && - isxdigit(cp[4]) && - !strncmp(cp+5, "h ", 2)) - return 7; - } +/* if (len > 6) { */ +/* // "return " */ +/* if (cp[0] == 'r' && */ +/* isxdigit(cp[1]) && */ +/* !strncmp(cp+2, "turn ", 5)) */ +/* return 7; */ +/* // "switch " */ +/* if (cp[0] == 's' && */ +/* !strncmp(cp+1, "wit", 3) && */ +/* isxdigit(cp[4]) && */ +/* !strncmp(cp+5, "h ", 2)) */ +/* return 7; */ +/* } */ - if (len > 5) { - // "while " and "while(" - if (cp[0] == 'w' && - !strncmp(cp+1, "hil", 3) && - isxdigit(cp[4]) && - (cp[5] == ' ' || cp[5] == '(')) - return 6; - } +/* if (len > 5) { */ +/* // "while " and "while(" */ +/* if (cp[0] == 'w' && */ +/* !strncmp(cp+1, "hil", 3) && */ +/* isxdigit(cp[4]) && */ +/* (cp[5] == ' ' || cp[5] == '(')) */ +/* return 6; */ +/* } */ - if (len > 4) { - // "else " and "else{" - if (cp[0] == 'e' && - !strncmp(cp, "ls", 2) && - isxdigit(cp[3]) && - (cp[4] == ' ' || cp[4] == '{')) - return 5; - } +/* if (len > 4) { */ +/* // "else " and "else{" */ +/* if (cp[0] == 'e' && */ +/* !strncmp(cp, "ls", 2) && */ +/* isxdigit(cp[3]) && */ +/* (cp[4] == ' ' || cp[4] == '{')) */ +/* return 5; */ +/* } */ - if (len > 3) { - // "var " - if (cp[0] == 'v' && - isxdigit(cp[1]) && - cp[2] == 'r' && - cp[3] == ' ') - return 4; - } +/* if (len > 3) { */ +/* // "var " */ +/* if (cp[0] == 'v' && */ +/* isxdigit(cp[1]) && */ +/* cp[2] == 'r' && */ +/* cp[3] == ' ') */ +/* return 4; */ +/* } */ - return 0; -} +/* return 0; */ +/* } */ @@ -781,9 +801,10 @@ unsigned int capacityJS3 (char* buf, int len, int mode) { } else { bp = bp+j+1; } -// #ifdef DEBUG -// printf("got |%c|\n", *(bp-1)); -// #endif + + if (len < buf + len - bp) { + fprintf(stderr, "HERE\n"); + } j = offset2Hex(bp, (buf+len)-bp, 1); } // while return cnt; @@ -804,12 +825,20 @@ unsigned int capacityJS3 (char* buf, int len, int mode) { } else { bp = bp+j+1; } -#ifdef DEBUG -printf("got |%c|\n", *(bp-1)); -#endif + + if (len < jsEnd - buf || len < jsEnd - bp) { + fprintf(stderr, "HERE2\n"); + } + + j = offset2Hex(bp, jsEnd-bp, 1); } // while (j != -1) + if (buf + len < bp + 9) { + fprintf(stderr, "HERE3\n"); + } + + bp += 9; } // while (bp < (buf+len)) return cnt; diff --git a/src/steg/payloads.h b/src/steg/payloads.h index 7d66bbf..7629b14 100644 --- a/src/steg/payloads.h +++ b/src/steg/payloads.h @@ -153,7 +153,7 @@ char * strInBinary (const char *pattern, unsigned int patternLen, const char *bl unsigned int capacityPDF (char* buf, int len); unsigned int get_max_PDF_capacity(void); int find_content_length (char *hdr, int hlen); -int find_uri_type(char* buf); +int find_uri_type(char* buf, int size); int gen_response_header(char* content_type, int gzip, int length, char* buf, int buflen); diff --git a/src/steg/x_http.c b/src/steg/x_http.c index eb08401..c26fe1f 100644 --- a/src/steg/x_http.c +++ b/src/steg/x_http.c @@ -71,7 +71,7 @@ x_http_detect(conn_t *conn) { struct evbuffer *buf = conn_get_inbound(conn); unsigned char *data; - return 0; + return 0; /* Look for the text of http_response_1. */ if (evbuffer_get_length(buf) >= sizeof http_response_1 - 1) { diff --git a/src/steg/x_http2.c b/src/steg/x_http2.c index 3695c27..a1bc100 100644 --- a/src/steg/x_http2.c +++ b/src/steg/x_http2.c @@ -51,8 +51,8 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. -#define MIN_COOKIE_SIZE 128 -#define MAX_COOKIE_SIZE 2048 +#define MIN_COOKIE_SIZE 24 +#define MAX_COOKIE_SIZE 1024 int @@ -187,7 +187,7 @@ x_http2_detect(conn_t *conn) struct evbuffer *buf = conn_get_inbound(conn); unsigned char *data; - // return 0; + //return 0; /***** Here is a list of HTTP response codes extracted from the server-portals.out trace @@ -490,7 +490,7 @@ x_http2_client_cookie_transmit (steg_t *s, struct evbuffer *source, conn_t *conn conn_cease_transmission(conn); - downcast_steg(s)->type = find_uri_type(buf); + downcast_steg(s)->type = find_uri_type(buf, sizeof(buf)); downcast_steg(s)->have_transmitted = 1; return 0; } @@ -528,6 +528,10 @@ int gen_uri_field(char* uri, unsigned int uri_sz, char* data, int datalen) { if (r == 0 && datalen > 0) uri[so_far++] = '/'; + if (r == 2 && datalen > 0) + uri[so_far++] = '_'; + + if (so_far > uri_sz - 6) { fprintf(stderr, "too small\n"); return 0; @@ -636,7 +640,7 @@ x_http2_client_uri_transmit (steg_t *s, struct evbuffer *source, conn_t *conn) { evbuffer_drain(source, slen); conn_cease_transmission(conn); - downcast_steg(s)->type = find_uri_type(outbuf); + downcast_steg(s)->type = find_uri_type(outbuf, sizeof(outbuf)); downcast_steg(s)->have_transmitted = 1; return 0; @@ -675,7 +679,7 @@ x_http2_transmit(steg_t *s, struct evbuffer *source, conn_t *conn) the only plausible places to put it are the URL and cookies. This presently uses the URL. And it can't be binary. */ - if (evbuffer_get_length(source) < 128) + if (evbuffer_get_length(source) < 72) return x_http2_client_uri_transmit(s, source, conn); //@@ return x_http2_client_cookie_transmit(s, source, conn); //@@ } @@ -736,21 +740,21 @@ x_http2_server_receive(steg_t *s, conn_t *conn, struct evbuffer *dest, struct ev log_debug("SERVER received request header of length %d", (int)s2.pos); data = evbuffer_pullup(source, s2.pos+4); + if (data == NULL) { log_debug("SERVER evbuffer_pullup fails"); return RECV_BAD; } - limit = data + s2.pos; - type = find_uri_type((char *)data); + data[s2.pos+3] = 0; - data[s2.pos+4] = 0; - // fprintf(stderr, "data = %s\n", data); + limit = data + s2.pos; + + type = find_uri_type((char *)data, s2.pos+4); if (strstr((char*) data, "Cookie") != NULL) { - data = (unsigned char*) strstr((char*) data, "Cookie:"); - p = data + sizeof "Cookie: "-1; + p = (unsigned char*) strstr((char*) data, "Cookie:") + + sizeof "Cookie: "-1; cookie_mode = 1; } else @@ -784,8 +788,6 @@ x_http2_server_receive(steg_t *s, conn_t *conn, struct evbuffer *dest, struct ev outbuf[sofar] = 0; - // fprintf(stderr, "recvd = %d\n", sofar); - if (secondhalf) { fprintf(stderr, "incorrect cookie or uri recovery \n"); exit(-1);

1 0

[stegotorus/master] forgot to commit Makefile change
by zwol＠torproject.org 20 Jul '12

20 Jul '12

commit 067e85e76d81b81cc712465e13b332c91c3e3aed Author: Jeffrey Wang <jeffreyw(a)stanford.edu> Date: Sun Dec 4 08:26:50 2011 +0000 forgot to commit Makefile change git-svn-id: svn+ssh://spartan.csl.sri.com/svn/private/DEFIANCE@170 a58ff0ac-194c-e011-a152-003048836090 --- Makefile.am | 1 + 1 files changed, 1 insertions(+), 0 deletions(-) diff --git a/Makefile.am b/Makefile.am index ebe3fdd..f3ed040 100644 --- a/Makefile.am +++ b/Makefile.am @@ -21,6 +21,7 @@ PROTOCOLS = \ STEGANOGRAPHERS = \ src/steg/cookies.cc \ src/steg/crc32.cc \ + src/steg/embed.cc \ src/steg/http.cc \ src/steg/jsSteg.cc \ src/steg/payloads.cc \

1 0

[stegotorus/master] Linda's start script for obfsproxy server and client
by zwol＠torproject.org 20 Jul '12

20 Jul '12

commit f76325a6ba1a1b5b91323942ebd1759180b2257d Author: Linda Briesemeister <linda.briesemeister(a)sri.com> Date: Thu Nov 17 22:24:48 2011 +0000 Linda's start script for obfsproxy server and client git-svn-id: svn+ssh://spartan.csl.sri.com/svn/private/DEFIANCE@147 a58ff0ac-194c-e011-a152-003048836090 --- start-obfsproxy.sh | 120 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 120 insertions(+), 0 deletions(-) diff --git a/start-obfsproxy.sh b/start-obfsproxy.sh new file mode 100755 index 0000000..06439fe --- /dev/null +++ b/start-obfsproxy.sh @@ -0,0 +1,120 @@ +#!/bin/bash + +ODIR=~/src/DEFIANCE/stegotorus + +################################################################################ +# helper functions: + +usage () { +if [ $# -gt 0 ]; then + echo " *** ERROR: $1" +fi +cat << EOF + +usage: $0 <OPTIONS> [server|client] [install-dir] + +Start obfsproxy server or client with given options. If the optional install-dir +is given, override the value set in the script. + +OPTIONS: + -h Show this message + -i <addr> IP address (default: 127.0.0.1) + -p <n> port number (default: 8080) + -l <severity> Log severity: warn, error, debug (default: debug) + -b <host> Host name (or IP address) of Tor Bridge + with port number attached via ':' or omitted + (default: 87.73.82.145:8080) + -n <n> Multiply the number of IP addresses on the client +EOF +} + +################################################################################ +# parse command line: + +# default values: +IP=127.0.0.1 +PORT=8080 +N=1 +LOG=debug +BRIDGE_IP=87.73.82.145 +BRIDGE_PORT=8080 +while getopts "hi:p:l:b:n:" OPTION +do + case $OPTION in + h|\?) + usage; exit 1 + ;; + i) + IP=$OPTARG + ;; + p) + PORT=$OPTARG + ;; + n) + N=$OPTARG + ;; + l) + LOG=`echo $OPTARG | tr '[A-Z]' '[a-z]'` # make lower case + ;; + b) + arr=(${OPTARG//:/ }) + BRIDGE_IP=${arr[0]} + if [ ${#arr[@]} -gt 1 ]; then + BRIDGE_PORT=${arr[1]} + fi + ;; + esac + shift $((OPTIND-1)); OPTIND=1 +done + +# test if $LOG is valid +case $LOG in + debug|warn|error) + ;; + *) + usage "Unknown log level given: $LOG"; exit 1 + ;; +esac + +# now $@ has remaining arguments: +if [ $# -lt 1 ]; then + usage "need 'server' or 'client' as argument"; exit 1 +fi +TYPE=`echo $1 | tr '[A-Z]' '[a-z]'` # turn argument into lower case +case $TYPE in + server|client) + ;; + *) + usage "argument $1 not recognized"; exit 1 + ;; +esac + +# check optional install location given as an argument +if [ $# -gt 1 ]; then + if [[ ! -d $2 ]]; then + usage "argument $2 is not a directory"; exit 1 + fi + if [[ ! -x $2/obfsproxy ]]; then + usage "directory $2 does not contain executable of 'obfsproxy'"; exit 1 + fi + ODIR=$2 +fi + +################################################################################ +# start obfsproxy + +echo "Using obfsproxy in \"$ODIR\"" +cd $ODIR +export EVENT_NOKQUEUE=yes +case $TYPE in + server) + ./obfsproxy --log-min-severity=$LOG chop server $BRIDGE_IP:$BRIDGE_PORT $IP:$PORT + ;; + client) + IPS="" + for (( c=1; c<=$N; c++)) ; do + IPS="${IPS}${IP}:${PORT} x_http2 " ; + done + ./obfsproxy --log-min-severity=$LOG chop socks 127.0.0.1:1080 $IPS + ;; +esac

1 0

[stegotorus/master] Merge branch 'master' into stegotorus
by zwol＠torproject.org 20 Jul '12

20 Jul '12

commit 250e0f9ceaae483ae78e934529682c528d2ac7c0 Merge: 15ccb15 200c1ea Author: Zack Weinberg <zackw(a)cmu.edu> Date: Thu Dec 1 23:29:48 2011 +0000 Merge branch 'master' into stegotorus .gitignore | 6 +- LICENSE | 39 +- Makefile.am | 99 ++-- README | 8 +- autogen.sh | 2 - configure.ac | 55 +- doc/TODO | 30 +- doc/protocol-spec.txt | 104 --- doc/tor-obfs-howto.txt | 101 --- doc/tor-st-howto.txt | 101 +++ m4/pkg.m4 | 10 +- src/connections.c | 392 ----------- src/connections.cc | 400 ++++++++++++ src/connections.h | 103 +++- src/container.c | 1438 ----------------------------------------- src/container.h | 683 ------------------- src/crypt.c | 216 ------ src/crypt.cc | 269 ++++++++ src/crypt.h | 152 +++-- src/genmodtable.sh | 12 +- src/ht.h | 471 -------------- src/main.c | 399 ------------ src/main.cc | 398 ++++++++++++ src/network.c | 827 ----------------------- src/network.cc | 826 +++++++++++++++++++++++ src/protocol.c | 58 -- src/protocol.cc | 41 ++ src/protocol.h | 314 ++++------ src/protocol/chop.cc | 1308 +++++++++++++++++++++++++++++++++++++ src/protocol/x_null.cc | 243 +++++++ src/protocols/chop.c | 1379 --------------------------------------- src/protocols/dummy.c | 256 -------- src/protocols/obfs2.c | 659 ------------------- src/protocols/obfs2.h | 81 --- src/protocols/x_dsteg.c | 572 ---------------- src/protocols/x_rr.c | 1072 ------------------------------ src/rng.cc | 88 +++ src/rng.h | 19 +- src/sha256.c | 290 --------- src/sha256.h | 16 - src/socks.c | 614 ------------------ src/socks.cc | 612 ++++++++++++++++++ src/socks.h | 4 +- src/steg.c | 67 -- src/steg.cc | 44 ++ src/steg.h | 151 +++--- src/steg/x_http.c | 371 ----------- src/steg/x_http.cc | 360 ++++++++++ src/test/genunitgrps.sh | 2 +- src/test/itestlib.py | 165 +++++ src/test/obfstestlib.py | 165 ----- src/test/test_socks.py | 10 +- src/test/test_tl.py | 36 +- src/test/tinytest.c | 383 ----------- src/test/tinytest.cc | 383 +++++++++++ src/test/tltester.c | 662 ------------------- src/test/tltester.cc | 659 +++++++++++++++++++ src/test/unittest.c | 209 ------ src/test/unittest.cc | 119 ++++ src/test/unittest.h | 4 - src/test/unittest_config.c | 131 ---- src/test/unittest_config.cc | 86 +++ src/test/unittest_container.c | 768 ---------------------- src/test/unittest_crypt.c | 180 ----- src/test/unittest_crypt.cc | 407 ++++++++++++ src/test/unittest_obfs2.c | 268 -------- src/test/unittest_socks.c | 597 ----------------- src/test/unittest_socks.cc | 597 +++++++++++++++++ src/test/unittest_transfer.c | 146 ----- src/test/unittest_transfer.cc | 113 ++++ src/util.c | 709 -------------------- src/util.cc | 706 ++++++++++++++++++++ src/util.h | 170 +++-- 73 files changed, 8524 insertions(+), 14911 deletions(-) diff --cc Makefile.am index e8b68f5,de3c9b2..ebf44d9 --- a/Makefile.am +++ b/Makefile.am @@@ -2,72 -2,55 +2,63 @@@ # Copyright 2011 Nick Mathewson, George Kadianakis, Zack Weinberg # See LICENSE for other credits and copying information - ACLOCAL_AMFLAGS = -I m4 - WARNINGS = -std=gnu99 -pedantic -Wall -Wextra -Wformat=2 -Wwrite-strings \ - -Wstrict-prototypes -Wmissing-prototypes -Wdeclaration-after-statement \ - -Wno-unused-parameter -Wno-overlength-strings -Wno-long-long -Werror - AM_CPPFLAGS = -I. -I$(srcdir)/src -D_FORTIFY_SOURCE=2 - AM_CFLAGS = $(WARNINGS) @libevent_CFLAGS@ @libcrypto_CFLAGS@ - LDADD = libobfsproxy.a @libevent_LIBS@ @libcrypto_LIBS@ @ws32_LIBS@ + ACLOCAL_AMFLAGS = -I m4 --install - bin_PROGRAMS = obfsproxy - noinst_LIBRARIES = libobfsproxy.a - noinst_PROGRAMS = unittests tltester + WARNINGS = -Werror -Wall -Wextra -Wformat=2 + + AM_CXXFLAGS = -std=c++98 $(WARNINGS) + AM_CPPFLAGS = -I. -I$(srcdir)/src -D_FORTIFY_SOURCE=2 $(lib_CPPFLAGS) + LDADD = libstegotorus.a + + noinst_LIBRARIES = libstegotorus.a + noinst_PROGRAMS = unittests tltester + bin_PROGRAMS = stegotorus PROTOCOLS = \ - src/protocols/dummy.c \ - src/protocols/chop.c \ - src/protocols/obfs2.c \ - src/protocols/x_dsteg.c \ - src/protocols/x_rr.c + src/protocol/chop.cc \ + src/protocol/x_null.cc STEGANOGRAPHERS = \ - src/steg/x_http.c \ - src/steg/x_http.cc ++ src/steg/x_http.cc \ + src/steg/x_http2.c \ + src/steg/payloads.c \ + src/steg/cookies.c \ + src/steg/jsSteg.c \ + src/steg/swfSteg.c \ + src/steg/zpack.c \ + src/steg/crc32.c \ + src/steg/pdfSteg.c - libobfsproxy_a_SOURCES = \ - src/connections.c \ - src/container.c \ - src/crypt.c \ - src/network.c \ - src/protocol.c \ - src/socks.c \ - src/steg.c \ - src/util.c \ + libstegotorus_a_SOURCES = \ + src/connections.cc \ + src/crypt.cc \ + src/network.cc \ + src/protocol.cc \ + src/rng.cc \ + src/socks.cc \ + src/steg.cc \ + src/util.cc \ $(PROTOCOLS) $(STEGANOGRAPHERS) - nodist_libobfsproxy_a_SOURCES = protolist.c steglist.c - - if NEED_SHA256 - libobfsproxy_a_SOURCES += src/sha256.c - endif + nodist_libstegotorus_a_SOURCES = protolist.cc steglist.cc - obfsproxy_SOURCES = \ - src/main.c + stegotorus_SOURCES = \ + src/main.cc UTGROUPS = \ - src/test/unittest_container.c \ - src/test/unittest_crypt.c \ - src/test/unittest_socks.c \ - src/test/unittest_obfs2.c \ - src/test/unittest_config.c \ - src/test/unittest_transfer.c + src/test/unittest_crypt.cc \ + src/test/unittest_socks.cc \ + src/test/unittest_config.cc \ + src/test/unittest_transfer.cc unittests_SOURCES = \ - src/test/tinytest.c \ - src/test/unittest.c \ + src/test/tinytest.cc \ + src/test/unittest.cc \ $(UTGROUPS) - nodist_unittests_SOURCES = unitgrplist.c + nodist_unittests_SOURCES = unitgrplist.cc - tltester_SOURCES = src/test/tltester.c + tltester_SOURCES = src/test/tltester.cc noinst_HEADERS = \ src/connections.h \ diff --cc src/steg/x_http.cc index 0000000,9ee6eb5..e1d9780 mode 000000,100644..100644 --- a/src/steg/x_http.cc +++ b/src/steg/x_http.cc @@@ -1,0 -1,359 +1,360 @@@ + /* Copyright 2011 Zack Weinberg + See LICENSE for other credits and copying information + */ + + #include "util.h" + #include "connections.h" + #include "steg.h" + #include "crypt.h" + + #include <event2/buffer.h> + + /* This is an example steganography module. Don't use it to disguise real + traffic! It packages client->server traffic as HTTP GET requests and + server->client traffic as HTTP responses, but makes no actual attempt + to obscure the data proper. */ + + namespace { + struct x_http : steg_t + { + bool have_transmitted : 1; + bool have_received : 1; + STEG_DECLARE_METHODS(x_http); + }; + } + + STEG_DEFINE_MODULE(x_http, + 1024, /* client-server max data rate - made up */ + 10240, /* server-client max data rate - ditto */ + 1, /* max concurrent connections per IP */ + 1); /* max concurrent IPs */ + + /* Canned HTTP query and response headers. */ + static const char http_query_1[] = + "GET /"; + static const char http_query_2[] = + " HTTP/1.1\r\n" + "Host: "; + static const char http_query_3[] = + "\r\n" + "Connection: close\r\n\r\n"; + + static const char http_response_1[] = + "HTTP/1.1 200 OK\r\n" + "Expires: Thu, 01 Jan 1970 00:00:00 GMT\r\n" + "Cache-Control: no-store\r\n" + "Connection: close\r\n" + "Content-Type: application/octet-stream\r\n" + "Content-Length: "; + + + x_http::x_http() + : have_transmitted(false), have_received(false) + {} + + x_http::~x_http() + {} + + bool + x_http::detect(conn_t *conn) + { + struct evbuffer *buf = conn_get_inbound(conn); + uint8_t *data; ++ return 0; + + /* Look for the text of http_response_1. */ + if (evbuffer_get_length(buf) >= sizeof http_response_1 - 1) { + data = evbuffer_pullup(buf, sizeof http_response_1 - 1); + if (!memcmp(data, http_response_1, sizeof http_response_1 - 1)) + return true; + } + + /* The client always transmits "GET /" followed by at least four + characters that are either lowercase hex digits or equals + signs, so we need nine bytes of incoming data. */ + if (evbuffer_get_length(buf) >= 9) { + data = evbuffer_pullup(buf, 9); + if (!memcmp(data, "GET /", 5) && + (ascii_isxdigit(data[5]) || data[5] == '=') && + (ascii_isxdigit(data[6]) || data[6] == '=') && + (ascii_isxdigit(data[7]) || data[7] == '=') && + (ascii_isxdigit(data[8]) || data[8] == '=')) + return true; + } + + /* Didn't find either the client or the server pattern. */ + return false; + } + + size_t + x_http::transmit_room(conn_t *) + { + if (this->have_transmitted) + /* can't send any more on this connection */ + return 0; + + if (this->is_clientside) + /* per http://www.boutell.com/newfaq/misc/urllength.html, + IE<9 can handle no more than 2048 characters in the path + component of a URL; we're not talking to IE, but this limit + means longer paths look fishy; we hex-encode the path, so + we have to cut the number in half. */ + return 1024; + else { + if (!this->have_received) + return 0; + /* no practical limit applies */ + return SIZE_MAX; + } + } + + int + x_http::transmit(struct evbuffer *source, conn_t *conn) + { + struct evbuffer *dest = conn_get_outbound(conn); + + if (this->is_clientside) { + /* On the client side, we have to embed the data in a GET query somehow; + the only plausible places to put it are the URL and cookies. This + presently uses the URL. And it can't be binary. */ + struct evbuffer *scratch; + struct evbuffer_iovec *iv; + int i, nv; + + /* Convert all the data in 'source' to hexadecimal and write it to + 'scratch'. Data is padded to a multiple of four characters with + equals signs. */ + size_t slen = evbuffer_get_length(source); + size_t dlen = slen * 2; + + dlen = dlen + 3 - (dlen-1)%4; + if (dlen == 0) dlen = 4; + + scratch = evbuffer_new(); + if (!scratch) return -1; + if (evbuffer_expand(scratch, dlen)) { + evbuffer_free(scratch); + return -1; + } + + nv = evbuffer_peek(source, slen, NULL, NULL, 0); + iv = (struct evbuffer_iovec *)xzalloc(sizeof(struct evbuffer_iovec) * nv); + if (evbuffer_peek(source, slen, NULL, iv, nv) != nv) { + evbuffer_free(scratch); + free(iv); + return -1; + } + + for (i = 0; i < nv; i++) { + const uint8_t *p = (const uint8_t *)iv[i].iov_base; + const uint8_t *limit = p + iv[i].iov_len; + char hex[2], c; + while (p < limit) { + c = *p++; + hex[0] = "0123456789abcdef"[(c & 0xF0) >> 4]; + hex[1] = "0123456789abcdef"[(c & 0x0F) >> 0]; + evbuffer_add(scratch, hex, 2); + } + } + free(iv); + while (evbuffer_get_length(scratch) == 0 || + evbuffer_get_length(scratch) % 4 != 0) + evbuffer_add(scratch, "=", 1); + + if (evbuffer_add(dest, http_query_1, sizeof http_query_1-1) || + evbuffer_add_buffer(dest, scratch) || + evbuffer_add(dest, http_query_2, sizeof http_query_2-1) || + evbuffer_add(dest, conn->peername, strlen(conn->peername)) || + evbuffer_add(dest, http_query_3, sizeof http_query_3-1)) { + evbuffer_free(scratch); + return -1; + } + + evbuffer_free(scratch); + evbuffer_drain(source, slen); + conn_cease_transmission(conn); + this->have_transmitted = true; + return 0; + + } else { + /* On the server side, we just fake up some HTTP response headers + and then splat the data we were given. Binary is OK. */ + if (evbuffer_add(dest, http_response_1, sizeof http_response_1-1)) + return -1; + if (evbuffer_add_printf(dest, "%lu\r\n\r\n", + (unsigned long)evbuffer_get_length(source)) == -1) + return -1; + if (evbuffer_add_buffer(dest, source)) + return -1; + + conn_close_after_transmit(conn); + this->have_transmitted = true; + return 0; + } + } + + int + x_http::receive(conn_t *conn, struct evbuffer *dest) + { + struct evbuffer *source = conn_get_inbound(conn); + if (this->is_clientside) { + /* Linearize the buffer out past the longest possible + Content-Length header and subsequent blank line. 2**64 fits in + 20 characters, and then we have two CRLFs; minus one for the + NUL in sizeof http_response_1. Note that this does _not_ + guarantee that that much data is available. */ + + size_t hlen = evbuffer_get_length(source); + uint8_t *data, *p, *limit; + uint64_t clen; + + log_debug("x_http: %lu byte response stream available%s", + (unsigned long)hlen, + hlen >= sizeof http_response_1 - 1 ? "" : " (incomplete)"); + + if (this->have_received) { + log_warn("x_http: protocol error: multiple responses"); + return -1; + } + + if (hlen < sizeof http_response_1 - 1) + return 0; /* incomplete */ + + if (hlen > sizeof http_response_1 + 23) + hlen = sizeof http_response_1 + 23; + + data = evbuffer_pullup(source, hlen); + /* Validate response headers. */ + if (memcmp(data, http_response_1, sizeof http_response_1 - 1)) + return -1; + + /* There should be an unsigned number immediately after the text of + http_response_1, followed by the four characters \r\n\r\n. + We may not have the complete number yet. */ + p = data + sizeof http_response_1 - 1; + limit = data + hlen; + clen = 0; + while (p < limit && '0' <= *p && *p <= '9') { + clen = clen*10 + *p - '0'; + p++; + } + if (p+4 > limit) + return 0; /* incomplete */ + if (p[0] != '\r' || p[1] != '\n' || p[2] != '\r' || p[3] != '\n') + return -1; + + p += 4; + hlen = p - data; + /* Now we know how much data we're expecting after the blank line. */ + if (evbuffer_get_length(source) < hlen + clen) + return 0; /* incomplete */ + + /* we are go */ + if (evbuffer_drain(source, hlen)) + return -1; + + if ((uint64_t)evbuffer_remove_buffer(source, dest, clen) != clen) + return -1; + + log_debug("x_http: decoded %lu byte response", + (unsigned long)(hlen + clen)); + + if (evbuffer_get_length(source) > 0) { + log_warn("x_http: protocol error: extra response data"); + return -1; + } + + this->have_received = 1; + conn_expect_close(conn); + return 0; + } else { + /* We need a scratch buffer here because the contract is that if + we hit a decode error we *don't* write anything to 'dest'. */ + struct evbuffer *scratch; + struct evbuffer_ptr s2, s3; + uint8_t *data, *p, *limit; + uint8_t c, h, secondhalf; + + log_debug("x_http: %lu byte query stream available", + (unsigned long)evbuffer_get_length(source)); + + if (this->have_received) { + log_warn("x_http: protocol error: multiple queries"); + return -1; + } + + /* Search for the second and third invariant bits of the query headers + we expect. We completely ignore the contents of the Host header. */ + s2 = evbuffer_search(source, http_query_2, + sizeof http_query_2 - 1, NULL); + if (s2.pos == -1) { + log_debug("x_http: did not find second piece of HTTP query"); + return 0; + } + s3 = evbuffer_search(source, http_query_3, + sizeof http_query_3 - 1, &s2); + if (s3.pos == -1) { + log_debug("x_http: did not find third piece of HTTP query"); + return 0; + } + log_assert(s3.pos + sizeof http_query_3 - 1 + <= evbuffer_get_length(source)); + + data = evbuffer_pullup(source, s2.pos); + if (memcmp(data, "GET /", sizeof "GET /"-1)) { + log_debug("x_http: unexpected HTTP verb: %.*s", 5, data); + return -1; + } + + p = data + sizeof "GET /"-1; + limit = data + s2.pos; + + scratch = evbuffer_new(); + if (!scratch) return -1; + if (evbuffer_expand(scratch, (limit - p)/2)) { + evbuffer_free(scratch); + return -1; + } + + secondhalf = 0; + while (p < limit) { + if (!secondhalf) c = 0; + if ('0' <= *p && *p <= '9') h = *p - '0'; + else if ('a' <= *p && *p <= 'f') h = *p - 'a' + 10; + else if ('A' <= *p && *p <= 'F') h = *p - 'A' + 10; + else if (*p == '=' && !secondhalf) { + p++; + continue; + } else { + evbuffer_free(scratch); + log_debug("x_http: decode error: unexpected URI character %c", *p); + return -1; + } + + c = (c << 4) + h; + if (secondhalf) + evbuffer_add(scratch, &c, 1); + secondhalf = !secondhalf; + p++; + } + + if (evbuffer_add_buffer(dest, scratch)) { + evbuffer_free(scratch); + log_debug("x_http: failed to transfer buffer"); + return -1; + } + evbuffer_drain(source, s3.pos + sizeof http_query_3 - 1); + evbuffer_free(scratch); + log_debug("x_http: decoded %lu byte query", + (unsigned long)(s3.pos + sizeof http_query_3 - 1)); + + if (evbuffer_get_length(source) > 0) { + log_warn("x_http: protocol error: extra query data"); + return -1; + } + + this->have_received = 1; + conn_transmit_soon(conn, 2); + return 0; + } + }

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tor-commits July 2012