On Tue, Apr 21, 2015 at 12:58 PM, Howard Chu hyc@symas.com wrote:

ahochhaus@samegoal.com wrote:

...

Full_Name: Andy Version: 2.4.30 OS: Debian Linux (Jessie) URL: ftp://ftp.openldap.org/incoming/ Submission from: (NULL) (67.188.115.159)

Hello,

When connecting over TLS to an LDAP server with high packet loss, my calls to ldap_sasl_bind_s() block forever some of the time despite have set a 10s limit on all of LDAP_OPT_NETWORK_TIMEOUT, LDAP_OPT_TIMEOUT and LDAP_OPT_TIMELIMIT.

I see the following stack trace on the deadlocked process.

 @     0x7f2ff0c0f8d0 (unknown)
 @     0x7f2ff0c0eac0 __libc_read
 @           0x5cdc68 sb_debug_read
 @           0x5c26f5 tlso_bio_read
 @           0x451b64 BIO_read
 @           0x49bf86 ssl3_read_n
 @           0x49d52b ssl3_get_record
 @           0x49caea ssl3_read_bytes
 @           0x496f61 ssl3_get_message
 @           0x496944 ssl3_get_finished
 @           0x5e4aab ssl3_connect
 @           0x5e164b ssl23_connect
 @           0x5c1b3c tlso_session_connect
 @           0x5b6773 ldap_int_tls_start
 @           0x5b3a77 ldap_int_open_connection
 @           0x5a730e ldap_new_connection
 @           0x5b3365 ldap_open_defconn
 @           0x5a68e3 ldap_send_initial_request
 @           0x5a4c1e ldap_sasl_bind
 @           0x5a4d99 ldap_sasl_bind_s

Inspecting the source, I see that SSL_connect() is called from tlso_session_connect(). Does openldap attempt to pass timeout information to openssl?

Sorry for the vague bug report. The issue is non-deterministic so it is hard to provide too much information. Please let me know what I can do to be more helpful.

I was able to find an old posting (from 2006) reporting a similar issue. I'm uncertain if the root cause is the same or not though.

http://www.openldap.org/lists/openldap-software/200601/msg00440.html

There is no API for setting a timeout in the TLS library.

http://www.openldap.org/lists/openldap-software/200707/msg00346.html

Thanks for the pointer. Feel free to close this issue.

-Andy