xref: /curl/docs/cmdline-opts/ssl.md (revision 2abfc759)
1---
2c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
3SPDX-License-Identifier: curl
4Long: ssl
5Help: Try enabling TLS
6Protocols: FTP IMAP POP3 SMTP LDAP
7Added: 7.20.0
8Category: tls imap pop3 smtp ldap
9Multi: boolean
10See-also:
11  - ssl-reqd
12  - insecure
13  - ciphers
14Example:
15  - --ssl pop3://example.com/
16---
17
18# `--ssl`
19
20Warning: this is considered an insecure option. Consider using --ssl-reqd
21instead to be sure curl upgrades to a secure connection.
22
23Try to use SSL/TLS for the connection - often referred to as STARTTLS or STLS
24because of the involved commands. Reverts to a non-secure connection if the
25server does not support SSL/TLS. See also --ftp-ssl-control and --ssl-reqd for
26different levels of encryption required.
27
28This option is handled in LDAP (added in 7.81.0). It is fully supported by the
29OpenLDAP backend and ignored by the generic ldap backend.
30
31Please note that a server may close the connection if the negotiation does
32not succeed.
33
34This option was formerly known as --ftp-ssl (added in 7.11.0). That option
35name can still be used but might be removed in a future version.
36