Strange SSL connection failure: ssl->need_bytes=4621 > 3939 #1375
Description
tl;dr
What does ssl->need_bytes=4621 > 3939 mean? I'm told it's generated from https://github.com/igrr/axtls-8266/blob/514b6685c5a84232caeed72dc5720c652bbe9f73/ssl/tls1.c#L1286 (thanks @Links2004) but I'm not sure how to take this investigation further.
Can you reproduce it?
I'm using Arduino 1.6.7 on OS X 10.11.2 and the 2.1.0-rc1 libs.
To reproduce my issue, use this sketch with the Debug Level set to HTTPClient:
#include <ESP8266WiFi.h>
#include <ESP8266HTTPClient.h>
void setup() {
Serial.begin(115200);
Serial.print("Connecting to wifi");
WiFi.begin("youknow", "whattodo");
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
Serial.println("\r\nWiFi connected.");
Serial.println("access point:");
Serial.println(WiFi.SSID());
Serial.println("ip address:");
Serial.println(WiFi.localIP());
}
void loop() {
// wait for WiFi connection
if(WiFi.status() == WL_CONNECTED) {
HTTPClient http;
//http.begin("https://api.twilio.com/", "79 E7 4F C0 02 71 C8 11 4A 30 7C 14 DA 09 AE 66 AB BB 50 1B");
http.begin("https://api.github.com/", "CF 05 98 89 CA FF 8E D8 5E 5C E0 C2 E4 F7 E6 C3 C7 50 DD 5C");
int result = http.POST("somedata=yo");
// error: ssl->need_bytes=4621 > 3939
Serial.println("status code: " + String(result));
if(result > 0) {
Serial.println("body:");
Serial.println(http.getString());
} else{
Serial.print("FAILED. error:"); Serial.println(http.errorToString(result).c_str());
Serial.println("body:");
Serial.println(http.getString());
}
http.end();
}
delay(10000);
}
You'll notice that using https://api.github.com/ everything works ok. Sure the request returns a 404 but the point is that the certificate SHA1 fingerprint matches and a SSL connection is made.
[HTTP-Client][begin] url: https://api.github.com/
[HTTP-Client][begin] host: api.github.com port: 443 url: / https: 1 httpsFingerprint: CF 05 98 89 CA FF 8E D8 5E 5C E0 C2 E4 F7 E6 C3 C7 50 DD 5C
[HTTP-Client] connect https...
please start sntp first !
[HTTP-Client] connected to api.github.com:443
[HTTP-Client] https certificate matches
[HTTP-Client][handleHeaderResponse] RX: 'HTTP/1.1 404 Not Found'
However with Twilio I get this strange ssl->need_bytes=4621 > 3939 in the debug output and the connection fails. I know the fingerprint is correct so I don't know what is different. On further investigation the only difference between the two certs I can see is the key length: Twilio is 4096 and github is 2048.
Can someone please help me out with this?
[HTTP-Client][begin] url: https://api.twilio.com/
[HTTP-Client][begin] host: api.twilio.com port: 443 url: / https: 1 httpsFingerprint: 79 E7 4F C0 02 71 C8 11 4A 30 7C 14 DA 09 AE 66 AB BB 50 1B
[HTTP-Client] connect https...
please start sntp first !
ssl->need_bytes=4621 > 3939
[HTTP-Client] failed connect to api.twilio.com:443
[HTTP-Client][returnError] error(-1): connection refused
status code: -1
FAILED. error:connection refused
body:
[HTTP-Client][returnError] error(-4): not connected
[HTTP-Client][end] tcp is closed
Bear in mind regarding the please start sntp first !, I get this failure wether I include configTime(3 * 3600, 0, "pool.ntp.org", "time.nist.gov"); or not.