CODEWITHSUNDEEP
c#downloadauthorizationwebclient
Starfleet Security
Starfleet Security

Reputation: 1843

WebClient DownloadFile with Authorization not working

I have tried just about everything I can think of to get this to work, including several things I've found online. All I'm trying to do is download a file (which has a direct link) from a website that I have to log in to.

I tried doing the following, with the "UploadValues":

WebClient myWebClient = new WebClient();
NameValueCollection myNameValueCollection = new NameValueCollection();
myNameValueCollection.Add("username", this.UserName);
myNameValueCollection.Add("password", this.Password);
byte[] responseArray = myWebClient.UploadValues(felony, myNameValueCollection);
myWebClient.DownloadFile(felony, localfelony);

and I've also tried putting the login info in the headers as well. I've also tried just setting the credentials, as you can see from the commented code:

WebClient client = new WebClient();
//client.UseDefaultCredentials = false;
//client.Credentials = new NetworkCredential(this.UserName, this.Password);
client.Headers.Add(HttpRequestHeader.Authorization, "Basic " + Convert.ToBase64String(Encoding.ASCII.GetBytes(this.UserName + ":" + this.Password)));
client.Headers.Add(HttpRequestHeader.UserAgent, "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/51.0.2704.103 Safari/537.36");
//client.Headers.Add(HttpRequestHeader.Cookie, this.webBrowser.Document.Cookie);
client.DownloadFile(felony, localfelony);

No matter what I try, the only thing I can get it to download is a file that ends up being the login page, as if it didn't accept the login info I passed.

I've looked at the headers and such, and I don't see anything out of the ordinary that would explain why this isn't working. Any ideas?

Upvotes: 1

Views: 3664

Answers (3)

Starfleet Security
Starfleet Security

Reputation: 1843

I could swear I had tried this before, but I guess maybe I had it just a little different or something. So it worked like this:

WebClient client = new WebClient();
client.UseDefaultCredentials = false;
client.Credentials = new NetworkCredential(this.UserName, this.Password);
client.Headers.Add(HttpRequestHeader.Cookie, "_gat=1; b46467afcb0b4bf5a47b2c6b22e3d284=mt84peq7u4r0bst72ejs5lb7p6; https://docs.stlucieclerk.com/=1,1; _ga=GA1.2.12049534.1467911267");
client.DownloadFile(webaddress, localname);

It was the cookie in the header that made it work. I thought I'd done that before, but maybe I did something involving a cookie that was different.

Upvotes: 1

Douglas Dwyer
Douglas Dwyer

Reputation: 612

Try temporarily changing the certificate validation:

System.Net.Security.RemoteCertificateValidationCallback r = System.Net.ServicePointManager.ServerCertificateValidationCallback; System.Net.ServicePointManager.ServerCertificateValidationCallback = delegate(object s, System.Security.Cryptography.X509Certificates.X509Certificate certificate, System.Security.Cryptography.X509Certificates.X509Chain chain, System.Net.Security.SslPolicyErrors sslPolicyErrors) { return true; }; //Do downloading here... System.Net.ServicePointManager.ServerCertificateValidationCallback = r;

This would mean, however, that the webclient would accept any certificate, so see this post for more info.

Upvotes: 0

Jatin Nath Prusty
Jatin Nath Prusty

Reputation: 572

This seems to be a authentication/authorization issue.

There could be many reasons causing this like: 1) may be the authentication/authorization mechanism uses some kind of hash. 2) may be you are using the wrong kind of authentication mechanism ("Basic" as I can see). 3) may be you are getting authenticated but not authorized.

The best way to find the root cause is: Use Fiddler. Login using the UI page and try to download the file. While doing that capture the fiddler session. An there try to do the same with whatever code you have. Again capture the fiddler session. Compare the fiddler to find the difference.

Hope this helps.

Upvotes: 0

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