Hello.

 

Anybody has working setup with Oracle (SQLPlus)?

 

Mine ends up with „Connection reset by peer“.

 

 

Server

 

pid = /var/run/stunnel-oracle.pid

cert = /etc/stunnel/stunnel.pem

debug = 7

output = /var/log/stunnel/stunnel.log

client = no

[oracle]

accept = 1.2.3.4:11521

connect = 127.0.0.1:1521

 

stunnel -version

Initializing inetd mode configuration

stunnel 5.71 on x86_64-redhat-linux-gnu platform

Compiled/running with OpenSSL 1.1.1k  FIPS 25 Mar 2021

Threading:PTHREAD Sockets:POLL,IPv6,SYSTEMD TLS:ENGINE,FIPS,OCSP,PSK,SNI

Global options:

fips                   = no

RNDbytes               = 1024

RNDfile                = /dev/urandom

RNDoverwrite           = yes

Service-level options:

ciphers                = PROFILE=SYSTEM (with "fips = yes")

ciphers                = PROFILE=SYSTEM (with "fips = no")

ciphersuites           = TLS_AES_256_GCM_SHA384:TLS_AES_128_GCM_SHA256:TLS_CHACHA20_POLY1305_SHA256 (with TLSv1.3)

curves                 = P-256:P-521:P-384 (with "fips = yes")

curves                 = X25519:P-256:X448:P-521:P-384 (with "fips = no")

debug                  = daemon.notice

logId                  = sequential

options                = NO_SSLv2

options                = NO_SSLv3

securityLevel          = 2

sessionCacheSize       = 1000

sessionCacheTimeout    = 300 seconds

stack                  = 65536 bytes

TIMEOUTbusy            = 300 seconds

TIMEOUTclose           = 60 seconds

TIMEOUTconnect         = 10 seconds

TIMEOUTidle            = 43200 seconds

TIMEOUTocsp            = 5 seconds

verify                 = none

 

 

Client

 

debug = 7

output = stunnel.log

client = yes

[oracle]

accept = 127.0.0.1:50102

connect = 1.2.3.4:11521

verifyChain = no

 

stunnel 5.77 on x64-pc-mingw32-gnu platform

Compiled/running with OpenSSL 3.5.5 27 Jan 2026

Threading:WIN32 Sockets:SELECT,IPv6 TLS:ENGINE,FIPS,OCSP,PSK,SNI

Global options:

fips                   = no

RNDbytes               = 1024

RNDoverwrite           = yes

taskbar                = yes

Service-level options:

ciphers                = FIPS:!DH:!kDHEPSK (with "fips = yes")

ciphers                = HIGH:!aNULL:!SSLv2:!DH:!kDHEPSK (with "fips = no")

ciphersuites           = TLS_AES_256_GCM_SHA384:TLS_AES_128_GCM_SHA256:TLS_CHACHA20_POLY1305_SHA256 (with TLSv1.3)

curves                 = P-256:P-521:P-384 (with "fips = yes")

curves                 = X25519MLKEM768:X25519:P-256:X448:P-521:P-384 (with "fips = no")

debug                  = notice

logId                  = sequential

options                = NO_SSLv2

options                = NO_SSLv3

securityLevel          = 2

sessionCacheSize       = 1000

sessionCacheTimeout    = 300 seconds

stack                  = 131072 bytes

TIMEOUTbusy            = 300 seconds

TIMEOUTclose           = 60 seconds

TIMEOUTconnect         = 10 seconds

TIMEOUTidle            = 43200 seconds

TIMEOUTocsp            = 5 seconds

verify                 = none

 

Debug logs from server (client logs are similar)

 

2026.03.26 12:54:18 LOG7[main]: Found 1 ready file descriptor(s)

2026.03.26 12:54:18 LOG7[main]: FD=4 events=0x2001 revents=0x0

2026.03.26 12:54:18 LOG7[main]: FD=9 events=0x2001 revents=0x1

2026.03.26 12:54:18 LOG7[main]: Service [oracle] accepted (FD=3) from 4.5.6.7:54017

2026.03.26 12:54:18 LOG7[3]: Service [oracle] started

2026.03.26 12:54:18 LOG7[3]: Setting local socket options (FD=3)

2026.03.26 12:54:18 LOG7[3]: Option TCP_NODELAY set on local socket

2026.03.26 12:54:18 LOG5[3]: Service [oracle] accepted connection from 4.5.6.7:54017

2026.03.26 12:54:18 LOG6[3]: Peer certificate not required

2026.03.26 12:54:18 LOG7[3]: TLS state (accept): before SSL initialization

2026.03.26 12:54:18 LOG7[3]: TLS state (accept): before SSL initialization

2026.03.26 12:54:18 LOG7[3]: Initializing application specific data for session authenticated

2026.03.26 12:54:18 LOG7[3]: Decrypt session ticket callback

2026.03.26 12:54:18 LOG6[3]: Decrypted ticket for an authenticated session: yes

2026.03.26 12:54:18 LOG7[3]: SNI: no virtual services defined

2026.03.26 12:54:18 LOG7[3]: TLS state (accept): SSLv3/TLS read client hello

2026.03.26 12:54:18 LOG7[3]: Deallocating application specific data for session connect address

2026.03.26 12:54:18 LOG7[3]: TLS state (accept): SSLv3/TLS write server hello

2026.03.26 12:54:18 LOG7[3]: TLS state (accept): SSLv3/TLS write change cipher spec

2026.03.26 12:54:18 LOG7[3]: TLS state (accept): TLSv1.3 early data

2026.03.26 12:54:18 LOG7[3]: TLS state (accept): TLSv1.3 early data

2026.03.26 12:54:18 LOG7[3]: Initializing application specific data for session authenticated

2026.03.26 12:54:18 LOG7[3]: Decrypt session ticket callback

2026.03.26 12:54:18 LOG6[3]: Decrypted ticket for an authenticated session: yes

2026.03.26 12:54:18 LOG7[3]: SNI: no virtual services defined

2026.03.26 12:54:18 LOG7[3]: TLS state (accept): SSLv3/TLS read client hello

2026.03.26 12:54:18 LOG7[3]: TLS state (accept): SSLv3/TLS write server hello

2026.03.26 12:54:18 LOG7[3]: TLS state (accept): TLSv1.3 write encrypted extensions

2026.03.26 12:54:18 LOG7[3]: TLS state (accept): SSLv3/TLS write finished

2026.03.26 12:54:18 LOG7[3]: TLS state (accept): TLSv1.3 early data

2026.03.26 12:54:18 LOG7[3]: TLS state (accept): TLSv1.3 early data

2026.03.26 12:54:18 LOG7[3]: TLS state (accept): SSLv3/TLS read finished

2026.03.26 12:54:18 LOG7[3]:      4 server accept(s) requested

2026.03.26 12:54:18 LOG7[3]:      4 server accept(s) succeeded

2026.03.26 12:54:18 LOG7[3]:      0 server renegotiation(s) requested

2026.03.26 12:54:18 LOG7[3]:      2 session reuse(s)

2026.03.26 12:54:18 LOG7[3]:      3 internal session cache item(s)

2026.03.26 12:54:18 LOG7[3]:      0 internal session cache fill-up(s)

2026.03.26 12:54:18 LOG7[3]:      0 internal session cache miss(es)

2026.03.26 12:54:18 LOG7[3]:      0 external session cache hit(s)

2026.03.26 12:54:18 LOG7[3]:      0 expired session(s) retrieved

2026.03.26 12:54:18 LOG7[3]: Initializing application specific data for session authenticated

2026.03.26 12:54:18 LOG7[3]: Deallocating application specific data for session connect address

2026.03.26 12:54:18 LOG7[3]: Generate session ticket callback

2026.03.26 12:54:18 LOG7[3]: Initializing application specific data for session authenticated

2026.03.26 12:54:18 LOG7[3]: Deallocating application specific data for session connect address

2026.03.26 12:54:18 LOG7[3]: New session callback

2026.03.26 12:54:18 LOG6[3]: No peer certificate received

2026.03.26 12:54:18 LOG6[3]: Session id: 483B0F9A7D229A299E5FE0AF18B9BC00D26CFB781A363ABC612E6C8481EE8D11

2026.03.26 12:54:18 LOG7[3]: TLS state (accept): SSLv3/TLS write session ticket

2026.03.26 12:54:18 LOG6[3]: TLS accepted: previous session reused

2026.03.26 12:54:18 LOG6[3]: TLSv1.3 ciphersuite: TLS_AES_256_GCM_SHA384 (256-bit encryption)

2026.03.26 12:54:18 LOG6[3]: Peer temporary key: X25519, 253 bits

2026.03.26 12:54:18 LOG7[3]: Compression: null, expansion: null

2026.03.26 12:54:18 LOG6[3]: Session id: 483B0F9A7D229A299E5FE0AF18B9BC00D26CFB781A363ABC612E6C8481EE8D11

2026.03.26 12:54:18 LOG6[3]: s_connect: connecting 127.0.0.1:1521

2026.03.26 12:54:18 LOG7[3]: s_connect: s_poll_wait 127.0.0.1:1521: waiting 10 seconds

2026.03.26 12:54:18 LOG7[3]: FD=6 events=0x2001 revents=0x0

2026.03.26 12:54:18 LOG7[3]: FD=11 events=0x2005 revents=0x1

2026.03.26 12:54:18 LOG5[3]: s_connect: connected 127.0.0.1:1521

2026.03.26 12:54:18 LOG6[3]: persistence: 127.0.0.1:1521 cached

2026.03.26 12:54:18 LOG5[3]: Service [oracle] connected remote server from 127.0.0.1:43694

2026.03.26 12:54:18 LOG7[3]: Setting remote socket options (FD=11)

2026.03.26 12:54:18 LOG7[3]: Option TCP_NODELAY set on remote socket

2026.03.26 12:54:18 LOG7[3]: Remote descriptor (FD=11) initialized

2026.03.26 12:54:18 LOG6[3]: TLS fd: Connection reset by peer (104)

2026.03.26 12:54:18 LOG6[3]: transfer: SSL_read: Socket is closed

2026.03.26 12:54:18 LOG6[3]: TLS socket closed (SSL_read)

2026.03.26 12:54:18 LOG7[3]: Sent socket write shutdown

2026.03.26 12:54:18 LOG5[3]: Connection closed: 190 byte(s) sent to TLS, 663 byte(s) sent to socket

2026.03.26 12:54:18 LOG7[3]: Deallocating application specific data for session connect address

2026.03.26 12:54:18 LOG7[3]: Remote descriptor (FD=11) closed

2026.03.26 12:54:18 LOG7[3]: Local descriptor (FD=3) closed

2026.03.26 12:54:18 LOG7[3]: Service [oracle] finished (0 left)