Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Can't read data from the server #57

Open
realyukii opened this issue Oct 15, 2024 · 6 comments
Open

Can't read data from the server #57

realyukii opened this issue Oct 15, 2024 · 6 comments
Assignees
@kareem-wolfssl @lealem47

Comments

@realyukii
Copy link

I've read in the docs that recv_into will return zero if there's no more received data, but the following recv_into always immediately return 0 at the first call, I wondering is the way I code fundamentally wrong?

import wolfssl
import socket

sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM, 0)
secure_sock = wolfssl.wrap_socket(sock)
secure_sock.connect(("dns.google", 443))
secure_sock.write(b"GET / HTTP/1.1\r\nHost: dns.google\r\n\r\n")

response = b""
while secure_sock.recv_into(response, 1024) != 0:
    print("never executed")

print(response)

secure_sock.close()
@kareem-wolfssl kareem-wolfssl self-assigned this Oct 15, 2024
@lealem47
Copy link
Contributor

Hi @RealYukiSan,

To get this working, you'll have to make response into a mutable buffer. For eg:

response = bytearray(1024)  # A mutable buffer for the recv_into method
data = b""  # To accumulate the received data

while True:
    num_bytes = secure_sock.recv_into(response, 1024)
    if num_bytes == 0:
        break  # Stop if no more data is received
    data += response[:num_bytes]  # Accumulate the data read into 'data'

@lealem47 lealem47 mentioned this issue Oct 15, 2024
Open
@realyukii
Copy link
Author

Thanks @lealem47 for the help, I tried to print num_bytes, it seems work but the num_bytes never reach 0?

$ python test.py 
1024
354
1024
80
5

@lealem47
Copy link
Contributor

That means it never stops receiving data. Could be that the google server is sending you keep-alives

@realyukii
Copy link
Author

I don't see keep-alive header in the response:

$ python test.py 
bytearray(b'HTTP/1.1 200 OK\r\nContent-Security-Policy: object-src \'none\';base-uri \'self\';script-src \'nonce-m_z8CZg3UI2hfHXAVIjMYw\' \'strict-dynamic\' \'report-sample\'
 \'unsafe-eval\' \'unsafe-inline\' https: http:;report-uri https://csp.withgoogle.com/csp/honest_dns/1_0;frame-ancestors \'none\'\r\nStrict-Transport-Security: max-age=315360
00; includeSubDomains; preload\r\nX-Content-Type-Options: nosniff\r\nContent-Type: text/html; charset=UTF-8\r\nContent-Security-Policy-Report-Only: script-src \'none\'; form-
action \'none\'; frame-src \'none\'; report-uri https://csp.withgoogle.com/csp/scaffolding/ntdsgswbsc:55:0\r\nCross-Origin-Opener-Policy-Report-Only: same-origin; report-to=c
oop_reporting\r\nReport-To: {"group":"coop_reporting","max_age":2592000,"endpoints":[{"url":"https://csp.withgoogle.com/csp/report-to/scaffolding/ntdsgswbsc:55:0"}],}\r\nDate
: Tue, 15 Oct 2024 23:15:33 GMT\r\nServer: scaffolding on HTTPServer2\r\nCache-Control: private\r\nX-XSS-Protection: 0\r\nX-Frame-Options: SAMEORIGIN\r\nAlt-Svc: h3=":443"; m
a=2592000,h3-29=":443"; ma=2592000\r\nAcce')
bytearray(b'pt-Ranges: none\r\nVary: Accept-Encoding\r\nTransfer-Encoding: chunked\r\n\r\n565\r\n<!DOCTYPE html>\n<html lang="en"> <head> <title>Google Public DNS</title>  <m
eta charset="UTF-8"> <link href="/static/93dd5954/favicon.png" rel="shortcut icon" type="image/png"> <link href="/static/e6eca759/matter.min.css" rel="stylesheet"> <link href
="/static/b8536c37/shared.cssent-Type-Options: nosniff\r\nContent-Type: text/html; charset=UTF-8\r\nContent-Security-Policy-Report-Only: script-src \'none\'; form-action \'no
ne\'; frame-src \'none\'; report-uri https://csp.withgoogle.com/csp/scaffolding/ntdsgswbsc:55:0\r\nCross-Origin-Opener-Policy-Report-Only: same-origin; report-to=coop_reporti
ng\r\nReport-To: {"group":"coop_reporting","max_age":2592000,"endpoints":[{"url":"https://csp.withgoogle.com/csp/report-to/scaffolding/ntdsgswbsc:55:0"}],}\r\nDate: Tue, 15 O
ct 2024 23:15:33 GMT\r\nServer: scaffolding on HTTPServer2\r\nCache-Control: private\r\nX-XSS-Protection: 0\r\nX-Frame-Options: SAMEORIGIN\r\nAlt-Svc: h3=":443"; ma=2592000,h
3-29=":443"; ma=2592000\r\nAcce')
bytearray(b'" rel="stylesheet"> <meta name="viewport" content="width=device-width, initial-scale=1">  <link href="/static/d05cd6ba/root.css" rel="stylesheet"> </head> <body> 
<span class="filler top"></span>   <div class="logo" title="Google Public DNS"> <div class="logo-text"><span>Public DNS</span></div> </div>  <form action="/query" method="GET
">  <div class="row"> <label class="matter-textfield-outlined"> <input type="text" name="name" placeholder="&nbsp;"> <span>DNS Name</span> <p class="help"> Enter a domain (li
ke example.com) or IP address (like 8.8.8.8 or 2001:4860:4860::8844) here. </p> </label> <button class="matter-button-contained matter-primary" type="submit">Resolve</button>
 </div> </form>  <span class="filler bottom"></span> <footer class="row"> <a href="https://developers.google.com/speed/public-dns">Help</a> <a href="/cache">Cache Flush</a> <
span class="filler"></span> <a href="https://developers.google.com/speed/public-dns/docs/using"> Get Started with Google Public DNS </a> </footer>   <script nonce="m_')
bytearray(b'z8CZg3UI2hfHXAVIjMYw">document.forms[0].name.focus();</script> </body> </html>\r\ncale=1">  <link href="/static/d05cd6ba/root.css" rel="stylesheet"> </head> <body
> <span class="filler top"></span>   <div class="logo" title="Google Public DNS"> <div class="logo-text"><span>Public DNS</span></div> </div>  <form action="/query" method="G
ET">  <div class="row"> <label class="matter-textfield-outlined"> <input type="text" name="name" placeholder="&nbsp;"> <span>DNS Name</span> <p class="help"> Enter a domain (
like example.com) or IP address (like 8.8.8.8 or 2001:4860:4860::8844) here. </p> </label> <button class="matter-button-contained matter-primary" type="submit">Resolve</butto
n> </div> </form>  <span class="filler bottom"></span> <footer class="row"> <a href="https://developers.google.com/speed/public-dns">Help</a> <a href="/cache">Cache Flush</a>
 <span class="filler"></span> <a href="https://developers.google.com/speed/public-dns/docs/using"> Get Started with Google Public DNS </a> </footer>   <script nonce="m_')
bytearray(b'0\r\n\r\n3UI2hfHXAVIjMYw">document.forms[0].name.focus();</script> </body> </html>\r\ncale=1">  <link href="/static/d05cd6ba/root.css" rel="stylesheet"> </head> <
body> <span class="filler top"></span>   <div class="logo" title="Google Public DNS"> <div class="logo-text"><span>Public DNS</span></div> </div>  <form action="/query" metho
d="GET">  <div class="row"> <label class="matter-textfield-outlined"> <input type="text" name="name" placeholder="&nbsp;"> <span>DNS Name</span> <p class="help"> Enter a doma
in (like example.com) or IP address (like 8.8.8.8 or 2001:4860:4860::8844) here. </p> </label> <button class="matter-button-contained matter-primary" type="submit">Resolve</b
utton> </div> </form>  <span class="filler bottom"></span> <footer class="row"> <a href="https://developers.google.com/speed/public-dns">Help</a> <a href="/cache">Cache Flush
</a> <span class="filler"></span> <a href="https://developers.google.com/speed/public-dns/docs/using"> Get Started with Google Public DNS </a> </footer>   <script nonce="m_')

it seems to me like the response isn't finished yet, but it stuck after the last 5 bytes

@lealem47
Copy link
Contributor

Can you share your code that's printing numBytes

@realyukii
Copy link
Author 

import wolfssl
import socket

sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM, 0)
secure_sock = wolfssl.wrap_socket(sock)
secure_sock.connect(("dns.google", 443))
secure_sock.write(b"GET / HTTP/1.1\r\nHost: dns.google\r\n\r\n")

response = bytearray(1024)  # A mutable buffer for the recv_into method
data = b""  # To accumulate the received data

while True:
    num_bytes = secure_sock.recv_into(response, 1024)
    print(num_bytes)
    if num_bytes == 0:
        break  # Stop if no more data is received
    data += response[:num_bytes]  # Accumulate the data read into 'data'

secure_sock.close()

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Assignees

@kareem-wolfssl kareem-wolfssl

@lealem47 lealem47

Labels
None yet
Projects
None yet
Milestone
No milestone
Development

No branches or pull requests
3 participants
@kareem-wolfssl @lealem47 @realyukii