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[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;

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[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

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[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')

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[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);

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[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 \

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[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

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[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; + } + }

1 0

[stegotorus/master] enabled pdf
by zwol＠torproject.org 20 Jul '12

20 Jul '12

commit 518fce5e1e524e2647491ca03dbf6663d0da8cb8 Author: Vinod Yegneswaran <vinod(a)csl.sri.com> Date: Tue Nov 15 07:58:08 2011 +0000 enabled pdf git-svn-id: svn+ssh://spartan.csl.sri.com/svn/private/DEFIANCE@144 a58ff0ac-194c-e011-a152-003048836090 --- src/steg/payloads.c | 3 ++- src/steg/x_http2.c | 2 +- 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/src/steg/payloads.c b/src/steg/payloads.c index 83487c5..2b82451 100644 --- a/src/steg/payloads.c +++ b/src/steg/payloads.c @@ -577,7 +577,8 @@ unsigned int find_client_payload(char* buf, int len, int type) { inbuf = payloads[r]; 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) { + find_uri_type(inbuf, p->length) != HTTP_CONTENT_JAVASCRIPT && + find_uri_type(inbuf, p->length) != HTTP_CONTENT_PDF) { goto next; } if (p->length > len) { diff --git a/src/steg/x_http2.c b/src/steg/x_http2.c index e714305..7377196 100644 --- a/src/steg/x_http2.c +++ b/src/steg/x_http2.c @@ -159,7 +159,7 @@ x_http2_new(rng_t *rng, unsigned int is_clientside) init_JS_payload_pool(HTTP_MSG_BUF_SIZE, TYPE_HTTP_RESPONSE, JS_MIN_AVAIL_SIZE); // init_JS_payload_pool(HTTP_MSG_BUF_SIZE, TYPE_HTTP_RESPONSE, JS_MIN_AVAIL_SIZE, HTTP_CONTENT_HTML); init_HTML_payload_pool(HTTP_MSG_BUF_SIZE, TYPE_HTTP_RESPONSE, HTML_MIN_AVAIL_SIZE); - // init_PDF_payload_pool(HTTP_MSG_BUF_SIZE, TYPE_HTTP_RESPONSE, PDF_MIN_AVAIL_SIZE); + init_PDF_payload_pool(HTTP_MSG_BUF_SIZE, TYPE_HTTP_RESPONSE, PDF_MIN_AVAIL_SIZE); init_SWF_payload_pool(HTTP_MSG_BUF_SIZE, TYPE_HTTP_RESPONSE, 0); }

1 0

[stegotorus/master] improved server response headers and cookies
by zwol＠torproject.org 20 Jul '12

20 Jul '12

commit d891d6ace21857caf8577c9a6dd0388a2c177907 Author: Vinod Yegneswaran <vinod(a)csl.sri.com> Date: Tue Nov 15 07:43:50 2011 +0000 improved server response headers and cookies git-svn-id: svn+ssh://spartan.csl.sri.com/svn/private/DEFIANCE@143 a58ff0ac-194c-e011-a152-003048836090 --- src/steg/cookies.c | 8 +++++- src/steg/jsSteg.c | 2 + src/steg/payloads.c | 57 ++++++++++++++++++++++++++++++++++++++++++++++++-- src/steg/payloads.h | 1 + 4 files changed, 63 insertions(+), 5 deletions(-) diff --git a/src/steg/cookies.c b/src/steg/cookies.c index e8d43b9..c773386 100644 --- a/src/steg/cookies.c +++ b/src/steg/cookies.c @@ -48,7 +48,8 @@ int gen_one_cookie(unsigned char* outbuf, int cookielen, unsigned char* data, in while (sofar < namelen) { c = rand() % (127 - 33) + 33; - if (c == '=' || c == ';' || c == '`' || c == '\'' || c == '%') + if (c == '=' || c == ';' || c == '`' || c == '\'' || c == '%' || c == '+' || c == '{' || c == '}' || + c == '<' || c == '>' || c == '?' || c == '#') continue; if ((c >= '0' && c <= '9') || (c >= 'a' && c <= 'f') || (c >= 'A' && c <= 'F') || (rand () % 4 != 0)) { @@ -65,9 +66,12 @@ int gen_one_cookie(unsigned char* outbuf, int cookielen, unsigned char* data, in while (sofar < cookielen) { c = rand() % (127 - 33) + 33; - if (c == '=' || c == ';' || c == '`' || c == '\'' || c == '%') + if (c == '=' || c == ';' || c == '`' || c == '\'' || c == '%' || c == '+' || c == '{' || c == '}' || + c == '<' || c == '>' || c == '?' || c == '#') continue; + + if ((c >= '0' && c <= '9') || (c >= 'a' && c <= 'f') || (c >= 'A' && c <= 'F') || (rand() % 4 != 0)) { if (data_consumed < datalen) outbuf[sofar++] = data[data_consumed++]; diff --git a/src/steg/jsSteg.c b/src/steg/jsSteg.c index 60b2d9a..1486255 100644 --- a/src/steg/jsSteg.c +++ b/src/steg/jsSteg.c @@ -998,6 +998,8 @@ x_http2_handle_client_JS_receive(steg_t *s, conn_t *conn, struct evbuffer *dest, buf2len = gzInflate(httpBody, httpBodyLen, buf2, HTTP_MSG_BUF_SIZE); if (buf2len <= 0) { log_warn("gzInflate for httpBody fails"); + fprintf(stderr, "gzInflate for httpBody fails"); + exit(-1); return RECV_BAD; } buf2[buf2len] = 0; diff --git a/src/steg/payloads.c b/src/steg/payloads.c index 76bb213..83487c5 100644 --- a/src/steg/payloads.c +++ b/src/steg/payloads.c @@ -303,6 +303,13 @@ void gen_rfc_1123_date(char* buf, int buf_size) { +void gen_rfc_1123_expiry_date(char* buf, int buf_size) { + time_t t = time(NULL) + rand() % 10000; + struct tm *my_tm = gmtime(&t); + strftime(buf, buf_size, "Expires: %a, %d %b %Y %H:%M:%S GMT\r\n", my_tm); +} + + @@ -310,7 +317,7 @@ int gen_response_header(char* content_type, int gzip, int length, char* buf, int char* ptr; // conservative assumption here.... - if (buflen < 256) { + if (buflen < 400) { fprintf(stderr, "gen_response_header: buflen too small\n"); return -1; } @@ -320,13 +327,57 @@ int gen_response_header(char* content_type, int gzip, int length, char* buf, int gen_rfc_1123_date(ptr, buflen - (ptr - buf)); ptr = ptr + strlen(ptr); + sprintf(ptr, "Server: Apache\r\n"); + ptr = ptr + strlen(ptr); + + switch(rand() % 9) { + case 1: + sprintf(ptr, "Vary: Cookie\r\n"); + ptr = ptr + strlen(ptr); + break; + + case 2: + sprintf(ptr, "Vary: Accept-Encoding, User-Agent\r\n"); + ptr = ptr + strlen(ptr); + break; + + case 3: + sprintf(ptr, "Vary: *\r\n"); + ptr = ptr + strlen(ptr); + break; + + } + + + switch(rand() % 4) { + case 2: + gen_rfc_1123_expiry_date(ptr, buflen - (ptr - buf)); + ptr = ptr + strlen(ptr); + } + + + + if (gzip) - sprintf(ptr, "Server: Apache\r\nContent-Length: %d\r\nContent-Encoding: gzip\r\nContent-Type: %s\r\nConnection: close\r\n\r\n", length, content_type); + sprintf(ptr, "Content-Length: %d\r\nContent-Encoding: gzip\r\nContent-Type: %s\r\n", length, content_type); else - sprintf(ptr, "Server: Apache\r\nContent-Length: %d\r\nContent-Type: %s\r\nConnection: close\r\n\r\n", length, content_type); + sprintf(ptr, "Content-Length: %d\r\nContent-Type: %s\r\n", length, content_type); ptr += strlen(ptr); + switch(rand() % 4) { + case 2: + case 3: + case 4: + sprintf(ptr, "Connection: Keep-Alive\r\n\r\n"); + break; + default: + sprintf(ptr, "Connection: close\r\n\r\n"); + break; + } + + ptr += strlen(ptr); + return ptr - buf; } diff --git a/src/steg/payloads.h b/src/steg/payloads.h index 7629b14..ace7dad 100644 --- a/src/steg/payloads.h +++ b/src/steg/payloads.h @@ -138,6 +138,7 @@ int get_payload (int contentType, int cap, char** buf, int* size); int has_eligible_HTTP_content (char* buf, int len, int type); int fixContentLen (char* payload, int payloadLen, char *buf, int bufLen); void gen_rfc_1123_date(char* buf, int buf_size); +void gen_rfc_1123_expiry_date(char* buf, int buf_size); int parse_client_headers(char* inbuf, char* outbuf, int len); int skipJSPattern (char *cp, int len); int isalnum_ (char c);

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[stegotorus/master] initial commit for 'embed' steg module, needs chopper changes to work
by zwol＠torproject.org 20 Jul '12

20 Jul '12

commit a43ae4dc1ce5475d6a1265af3fc318b4921bf36b Author: Jeffrey Wang <jeffreyw(a)stanford.edu> Date: Sun Dec 4 08:24:11 2011 +0000 initial commit for 'embed' steg module, needs chopper changes to work git-svn-id: svn+ssh://spartan.csl.sri.com/svn/private/DEFIANCE@169 a58ff0ac-194c-e011-a152-003048836090 --- src/steg/embed.cc | 234 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 234 insertions(+), 0 deletions(-) diff --git a/src/steg/embed.cc b/src/steg/embed.cc new file mode 100644 index 0000000..1e3c34c --- /dev/null +++ b/src/steg/embed.cc @@ -0,0 +1,234 @@ +#include "util.h" +#include "connections.h" +#include "steg.h" + +#include <event2/buffer.h> +#include <event2/event.h> +#include <stdio.h> +#include <unistd.h> +#include <time.h> + +typedef struct trace_t { + int num_pkt; // number of packets in trace + short *pkt_sizes; // packet sizes (positive = client->server) + int *pkt_times; // packet inter-arrival times +} trace_t; + +namespace { + struct embed : steg_t { + int cur_idx; // current trace index + trace_t *cur; // current trace + int cur_pkt; // current packet in the trace + struct timeval last_pkt; // time at which last packet was sent/received + + STEG_DECLARE_METHODS(embed); + }; +} + +static int embed_init = 0; // whether traces are initialized +static int embed_num_traces; // number of traces +static trace_t *embed_traces; // global array of all traces + +STEG_DEFINE_MODULE(embed, 1024, 1024, 1, 1); + +int millis_since(struct timeval *last) { + struct timeval cur; + int diff = 0; + gettimeofday(&cur, NULL); + + diff += (cur.tv_sec - last->tv_sec) * 1000; + diff += (cur.tv_usec - last->tv_usec) / 1000; + return diff; +} + +void init_embed_traces() { + // read in traces to use for connections + FILE *trace_file = fopen("traces/embed.txt", "r"); + fscanf(trace_file, "%d", &embed_num_traces); + embed_traces = (trace_t *)xmalloc(sizeof(trace_t) * embed_num_traces); + for (int i = 0; i < embed_num_traces; i++) { + int num_pkt; + fscanf(trace_file, "%d", &num_pkt); + embed_traces[i].num_pkt = num_pkt; + embed_traces[i].pkt_sizes = (short *)xmalloc(sizeof(short) * num_pkt); + embed_traces[i].pkt_times = (int *)xmalloc(sizeof(int) * num_pkt); + for (int j = 0; j < embed_traces[i].num_pkt; j++) { + fscanf(trace_file, "%hd %d", + &embed_traces[i].pkt_sizes[j], + &embed_traces[i].pkt_times[j]); + } + } + log_debug("read %d traces to use", embed_num_traces); + + srand(time(NULL)); + embed_init = 1; +} + +int get_random_trace() { + return rand() % embed_num_traces; +} + +bool advance_packet(embed *state) { + state->cur_pkt++; + return state->cur_pkt == state->cur->num_pkt; +} + +short get_pkt_size(embed *state) { + return abs(state->cur->pkt_sizes[state->cur_pkt]); +} + +bool is_outgoing(embed *state) { + return (state->cur->pkt_sizes[state->cur_pkt] < 0) ^ (state->is_clientside); +} + +int get_pkt_time(embed *state) { + return state->cur->pkt_times[state->cur_pkt]; +} + +bool is_finished(embed *state) { + if (state->cur_idx == -1) return true; + return state->cur_pkt >= state->cur->num_pkt; +} + +embed::embed() { + if (!embed_init) init_embed_traces(); + cur_idx = -1; + gettimeofday(&last_pkt, NULL); +} + +embed::~embed() { } + +bool embed::detect(conn_t * /* conn */) { + return 1; +} + +size_t embed::transmit_room(conn_t * /* conn */) { + if (cur_idx == -1 && is_clientside) { + cur_idx = get_random_trace(); + cur = &embed_traces[cur_idx]; + cur_pkt = 0; + } + + int time_diff = millis_since(&last_pkt); + size_t room; + + if (is_finished(this) || !is_outgoing(this)) return 0; + if (get_pkt_time(this) > time_diff+10) return 0; + + // 24 bytes for chop header, 2 bytes for data length + // 4 bytes for the index of a new trace + room = get_pkt_size(this) - 26; + if (cur_pkt == 0) { + room -= 4; + } + return room; +} + +int embed::transmit(struct evbuffer *source, conn_t *conn) { + struct evbuffer *dest = conn_get_outbound(conn); + short src_len = evbuffer_get_length(source); + short pkt_size = get_pkt_size(this); + short used = src_len + 2; + + // starting a new trace, send the index + if (cur_pkt == 0) { + if (evbuffer_add(dest, &cur_idx, 4) == -1) return -1; + used += 4; + log_debug("sending trace %d", cur_idx); + } + + log_debug("sending packet %d of trace %d", cur_pkt, cur_idx); + + // add the data length and data to the dest buffer + if (evbuffer_add(dest, &src_len, 2) == -1) return -1; + if (evbuffer_add_buffer(dest, source) == -1) return -1; + log_debug("sending data with length %d", src_len); + + // if there is more space in the packet, pad it + if (pkt_size > used) { + size_t padding = pkt_size - used; + unsigned char zero[padding]; + memset(zero, 0, padding); + evbuffer_add(dest, zero, padding); + } + + // check if this trace is finished and whether we need to send again + if (advance_packet(this)) { + log_debug("send finished trace"); + conn_close_after_transmit(conn); + } else if (is_outgoing(this)) { + log_debug("sending again in %d ms", get_pkt_time(this)); + conn_transmit_soon(conn, get_pkt_time(this)); + } + + // update last time + gettimeofday(&last_pkt, NULL); + return 0; +} + +int embed::receive(conn_t *conn, struct evbuffer *dest) { + struct evbuffer *source = conn_get_inbound(conn); + short src_len = evbuffer_get_length(source); + short pkt_size = 0; + + log_debug("receiving buffer of length %d", src_len); + + // if we are receiving the first packet of the trace, read the index + if (cur_idx == -1) { + if (evbuffer_remove(source, &cur_idx, 4) != 4) return -1; + cur = &embed_traces[cur_idx]; + cur_pkt = 0; + pkt_size += 4; + + log_debug("detected trace %d", cur_idx); + } + + // keep reading data and padding from the source, advancing the packet + // in the trace when we have read enough bytes + while (1) { + // the next full packet is not in the source buffer yet + int exp_pkt_size = get_pkt_size(this); + if (src_len < exp_pkt_size) break; + + // read data + short data_len; + if (evbuffer_remove(source, &data_len, 2) != 2) return -1; + if (data_len > 0) { + if (evbuffer_remove_buffer(source, dest, data_len) != data_len) { + return -1; + } + } + pkt_size += data_len + 2; + + // read padding + if (exp_pkt_size > pkt_size) { + size_t padding = exp_pkt_size - pkt_size; + if (evbuffer_drain(source, padding) == -1) return -1; + } + + src_len -= exp_pkt_size; + pkt_size = 0; + + log_debug("received packet %d of trace %d", + cur_pkt, cur_idx); + + // advance packet; if done with trace, sender should close connection + if (advance_packet(this)) { + conn_cease_transmission(conn); + conn_expect_close(conn); + log_debug("received last packet in trace"); + return 0; + } + } + + if (is_outgoing(this)) { + log_debug("preparing to send in %d ms", get_pkt_time(this)); + conn_transmit_soon(conn, get_pkt_time(this)); + } + + log_debug("remaining source length: %d", src_len); + + // update last time + gettimeofday(&last_pkt, NULL); + return 0; +}

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