commit 47fb64a72ab5c8503c2a35d970921c215238cdb5 Author: Vinod Yegneswaran vinod@csl.sri.com Date: Tue Nov 1 06:17:28 2011 +0000

enabled jskeyword skip

git-svn-id: svn+ssh://spartan.csl.sri.com/svn/private/DEFIANCE@112 a58ff0ac-194c-e011-a152-003048836090 --- src/steg/payloads.c | 58 ++++++++++++++++++++++++-------------------------- 1 files changed, 28 insertions(+), 30 deletions(-)

diff --git a/src/steg/payloads.c b/src/steg/payloads.c index 2782aa6..8d0b8fe 100644 --- a/src/steg/payloads.c +++ b/src/steg/payloads.c @@ -454,11 +454,9 @@ 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 && + if (find_uri_type(inbuf) != HTTP_CONTENT_SWF && find_uri_type(inbuf) != HTTP_CONTENT_JAVASCRIPT) - goto next; - if (p->length > len) { fprintf(stderr, "BUFFER TOO SMALL... \n"); goto next; @@ -497,7 +495,7 @@ unsigned int find_client_payload(char* buf, int len, int type) { int skipJSPattern (char *cp, int len) {

// log_debug("Turning off skipJSPattern for debugging"); - return 0; + // return 0;

if (len < 1) return 0;

@@ -575,6 +573,8 @@ int offset2Alnum_ (char *p, int range) { } }

+ + /* * offset2Hex returns the offset to the next usable hex char. * usable here refer to char that our steg module can use to encode @@ -608,15 +608,13 @@ int offset2Hex (char *p, int range, int isLastCharHex) { if (isLastCharHex) { if (isxdigit(*cp)) return 0; // base case else { - cp++; - i = offset2Alnum_(cp, p+range-cp); - while (i == 0) { - if (isxdigit(*cp)) return (cp-p); + while (cp < (p+range) && isalnum_(*cp)) { cp++; - i = offset2Alnum_(cp, p+range-cp); + if (isxdigit(*cp)) return (cp-p); } - if (i == -1) return -1; - // if (i > 0), fallthru and handle case 2 + if (cp >= (p+range)) return -1; + // non-alnum_ found + // fallthru and handle case 2 } }

@@ -626,29 +624,29 @@ int offset2Hex (char *p, int range, int isLastCharHex) {

i = offset2Alnum_(cp, p+range-cp); if (i == -1) return -1; - // isFirstWordChar = 1;

while (cp < (p+range) && i != -1) { - - if (i == 0) { - j = skipJSPattern(cp, p+range-cp); - if (j > 0) { - // cp points a word that should not be used (e.g., JS keyword) - cp = cp+j; isFirstWordChar = 1; - } else { // j == 0 - if (isFirstWordChar) { + + if (i == 0) { + if (isFirstWordChar) { + j = skipJSPattern(cp, p+range-cp); + if (j > 0) { + cp = cp+j; + } else { cp++; isFirstWordChar = 0; // skip the 1st char of a word - } - else { // we are in the middle of a word; no need to invoke skipJSPattern - if (isxdigit(*cp)) return (cp-p); - else cp++; } - } - } else { // i > 0 - cp += i; isFirstWordChar = 1; - } - i = offset2Alnum_(cp, p+range-cp); - + } else { // we are in the middle of a word; no need to invoke skipJSPattern + if (isxdigit(*cp)) return (cp-p); + if (! isalnum_(*cp)) { + isFirstWordChar = 1; + } + cp++; + } + } else { + cp += i; isFirstWordChar = 1; + } + i = offset2Alnum_(cp, p+range-cp); + } // while

// cannot find next usable hex char