c++ - OpenSSL EVP_DigestSignFinal segfault -

-

i'm trying sign message using openssl c api. following code segfaults because of exc_bad_access during either of calls evp_digestsignfinal. i'm using openssl 1.0.1g. tried switching newer digestsign* functions older sign* functions, , still segfaults.

private_key set evp_pkey_set1_rsa rsa key loaded pem file. first call evp_digestsignfinal fills s_len maximum possible length of signature signing algorithm, signature not being big enough shouldn't issue, , second call writes signature buffer , fills s_len length of signature.

i appreciate this.

vector<unsigned char> rsa_sha512_sign(         const vector<unsigned char>& document,          shared_ptr<evp_pkey> private_key) {     evp_md_ctx* md;     if (!(md = evp_md_ctx_create())) {         throw runtime_error("error initializing env_md_ctx.");     }      if (evp_digestsigninit(md, null, evp_sha512(), null, private_key.get())              != 1) {         throw runtime_error("error in evp_digestsigninit.");     }      if (evp_digestsignupdate(md, document.data(), document.size()) != 1) {         throw runtime_error("error computing hash on document.");     }     size_t s_len;     if (evp_digestsignfinal(md, null, &s_len) != 1) { // segfault here         throw runtime_error("error determining maximum signature size.");     }      vector<unsigned char> signature(s_len);     if (evp_digestsignfinal(md, signature.data(), &s_len) != 1) { // or here (or both)         throw runtime_error("error signing document.");     }     signature.resize(s_len);     evp_md_ctx_destroy(md);     return move(signature); }

the problem how initializing private_key. probably, mixing malloc() delete, , corrupting heap in process. need provide shared_ptr proper deleter pointer feed if pointer not created new.

    shared_ptr<rsa> r(rsa_new(), rsa_free);     shared_ptr<evp_pkey> p(evp_pkey_new(), evp_pkey_free);     shared_ptr<bignum> bn(bn_new(), bn_free);     vector<unsigned char> doc(0, 100);      bn_set_word(bn.get(), rsa_f4);     rsa_generate_key_ex(r.get(), 2048, bn.get(), 0);     evp_pkey_set1_rsa(p.get(), r.get());     rsa_sha512_sign(doc, p);

Comments

Post a Comment

Popular posts from this blog

c++ - OpenCV Error: Assertion failed <scn == 3 ::scn == 4> in unknown function, -

-
i read alot other solution still confused should mine... #include <opencv2/objdetect/objdetect.hpp> #include <opencv2/highgui/highgui.hpp> #include <opencv2/imgproc/imgproc.hpp> #include <iostream> #include <stdio.h> using namespace std; using namespace cv; int main(int argc, const char** argv) { //create cascade classifier object used face detection cascadeclassifier face_cascade; //use haarcascade_frontalface_alt.xml library face_cascade.load("haarcascade_frontalface_alt.xml"); //setup video capture device , link first capture device videocapture capturedevice; capturedevice.open(0); //setup image files used in capture process mat captureframe; mat grayscaleframe; //create window present results namedwindow("outputcapture", 1); //create loop capture , find faces while (true) { //capture new image frame capturedevice >> captureframe; ...
Read more

php - render data via PDO::FETCH_FUNC vs loop -

-
i've been using 2 methods render data. the first one: function name($id,$name){ return '<div id="'.$id.'">'.$name.'</div>'; } echo implode($pdo->query("select id,name user")->fetchall(pdo::fetch_func,'name')); the second one: $users = $pdo->query("select id,name user")->fetchall(pdo::fetch_obj); foreach($users $user){ echo name($user->id,$user->name); } i don't understand how pdo::fetch_func works. tried figure out. however, not well-documented. could please explain fetch mode? , also, 1 performs better? thank you. both methods wrong , have learn how use templates , how separate business logic presentation logic. $users = $pdo->query("select id,name user")->fetchall(pdo::fetch_obj); tpl::assign('users', $users); is code business logic part. then in template <?php foreach $users $row): ?> <div id="<?=$...
Read more

The canvas has been tainted by cross-origin data in chrome only -

-
uncaught securityerror: failed execute 'getimagedata' on 'canvasrenderingcontext2d': canvas has been tainted cross-origin data i getting above error in chrome. code(following) works fine in mozilla. have not corss domain issue. why above error in chrome? var wheel_canvas, wheel_context, can_w, can_h, wheel_grd; var large_radius = 160; var small_radius = 120; var wheel_canvas = document.getelementbyid('wheel_canvas'); var wheel_context = wheel_canvas.getcontext('2d'); var can_w = $(wheel_canvas).width(); var can_h = $(wheel_canvas).height(); var centerx = can_w / 2, centery = can_h / 2; var wheel_grd = null; test('#ff0000'); function test(hex) { $('#clrpicker').css({'left': 210, 'top': 210 }); inverted = hexbw(hex); $('#color_val_show').val(hex); current_color_hex_val_selected = hex; $('#color_val_show').css({'color':inverted,'background':hex}); fillgradient...
Read more