How to send cookie containing an unicode character in https GET request using poor windows sockets

Question

I'm creating win32 application and I work with one particular site. From previous requests I extracted some cookies and I want to implement them. But the problem is, one of these cookies contains unicode letter (latyn small letter e with dot above; 279 in ASCII table). It is the only cookie which is url-encoded. When decoding, I get char \u0117 and visual studio compiler gives me warning that it is unicode char and treats it as ? mark.

This is url-encoded cookie:

Set-Cookie: logged_user=%7B%22id%22%3A%22625936%22%2C%22email%22%3A%22vytautas.leveris%40gmail.com%22%2C%22display_name%22%3A%22Vytautas+L%5Cu0117veris%22%2C%22full_name%22%3A%22Vytautas+L%5Cu0117veris%22%2C%22photo%22%3A%22https%3A%5C%2F%5C%2Fwww.15min.lt%5C%2Fassets%5C%2Fimages%5C%2Fuser-default-icon.png%22%2C%22photo_small%22%3A%22https%3A%5C%2F%5C%2Fwww.15min.lt%5C%2Fassets%5C%2Fimages%5C%2Fuser-default-icon.png%22%2C%22photo_normal%22%3A%22https%3A%5C%2F%5C%2Fwww.15min.lt%5C%2Fassets%5C%2Fimages%5C%2Fuser-default-icon.png%22%2C%22staff%22%3Afalse%2C%22bookmarks%22%3A2%2C%22nb%22%3A1%7D; path=/

This is url-decoded cookie:

Set-Cookie: logged_user={\"id\":\"625936\",\"email\":\"vytautas.leveris@gmail.com\",\"display_name\":\"Vytautas L\u0117veris\",\"full_name\":\"Vytautas L\u0117veris\",\"photo\":\"https:\/\/www.15min.lt\/assets\/images\/user-default-icon.png\",\"photo_small\":\"https:\/\/www.15min.lt\/assets\/images\/user-default-icon.png\",\"photo_normal\":\"https:\/\/www.15min.lt\/assets\/images\/user-default-icon.png\",\"staff\":false,\"bookmarks\":2,\"nb\":1}; path=/

And finally, all http GET request:

strcpy(request,"GET / HTTP/1.1\r\nHost: www.15min.lt\r\nCookie: PHPSESSID=652e6dd2ac78de5db5392e53b9a0355a; logged_user={\"id\":\"625936\",\"email\":\"vytautas.leveris@gmail.com\",\"display_name\":\"Vytautas L\u0117veris\",\"full_name\":\"Vytautas L\u0117veris\",\"photo\":\"https:\/\/www.15min.lt\/assets\/images\/user-default-icon.png\",\"photo_small\":\"https:\/\/www.15min.lt\/assets\/images\/user-default-icon.png\",\"photo_normal\":\"https:\/\/www.15min.lt\/assets\/images\/user-default-icon.png\",\"staff\":false,\"bookmarks\":2,\"nb\":1}; remember_me=625936; device_token_625936=84c45e719fedc5949ced93ca0df54152\r\nUser-Agent: WindowsSockets2\r\n\r\n");

As I send message through winsock, I use char type.

Do I need to convert everything to wchar_t*? But then what about sending wchar_t* to server? Or perhaps I could change this character representation \u0117 into UTF8 char sequence? Any help and comments would be welcom.

score 0 · Accepted Answer · answered Jul 01 '19 at 21:18

0

I'd recommend to treat the data as opaque sequence of bytes, i.e., convert you custom data to UTF-8 bytes, run base 64 and use it as cookie value. See also: https://stackoverflow.com/a/49205256/696632. Then reverse the operation on the receiver side. You will probably require unsigned char*for the opaque byte data.

answered Jul 01 '19 at 21:18

Michael-O

18,123
6
55
121

But I can't control server side, so how should I inform server that I give to it UTF8 cookie value? – Vytautas Lėveris Jul 01 '19 at 21:32
A cookie value is always implementation defined. If you cannot negotiate for a transport format, you are out of luck. What can the server do? – Michael-O Jul 02 '19 at 09:08
OK. So I want to clarify: if I get url-encoded cookie from server, do I have to send it back decoded or leave as it is (with % symbols)? – Vytautas Lėveris Jul 02 '19 at 14:13
Retain the format the server provides you because this is probably the one the server can decode. – Michael-O Jul 02 '19 at 14:52
But by doing this server closes the connection and I don't get any response. – Vytautas Lėveris Jul 02 '19 at 15:55
@VytautasLėveris This basically means that there is no reliable way to figure this out unless you speak to the server operator/webapp developer. – Michael-O Jul 02 '19 at 16:03

How to send cookie containing an unicode character in https GET request using poor windows sockets

1 Answers1