CURLOPT_REDIR_PROTOCOLS_STR - Man Page

protocols allowed to redirect to

Synopsis

#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_REDIR_PROTOCOLS_STR,
                          char *spec);

Description

Pass a pointer to a string that holds a comma-separated list of case insensitive protocol names (URL schemes). That list limits what protocols libcurl may use in a transfer that it follows to in a redirect when CURLOPT_FOLLOWLOCATION(3) is enabled. This option allows applications to limit specific transfers to only be allowed to use a subset of protocols in redirections.

Protocols denied by CURLOPT_PROTOCOLS_STR(3) are not overridden by this option.

By default libcurl will allow HTTP, HTTPS, FTP and FTPS on redirects (since 7.65.2).  Older versions of libcurl allowed all protocols on redirect except several disabled for security reasons: Since 7.19.4 FILE and SCP are disabled, and since 7.40.0 SMB and SMBS are also disabled.

These are the available protocols:

DICT, FILE, FTP, FTPS, GOPHER, GOPHERS, HTTP, HTTPS, IMAP, IMAPS, LDAP, LDAPS, POP3, POP3S, RTMP, RTMPE, RTMPS, RTMPT, RTMPTE, RTMPTS, RTSP, SCP, SFTP, SMB, SMBS, SMTP, SMTPS, TELNET, TFTP

You can set "ALL" as a short-cut to enable all protocols. Note that by setting all, you may enable protocols that were not supported the day you write this but are introduced in a future libcurl version.

If trying to set a non-existing protocol or if no matching protocol at all is set, it returns error.

Default

HTTP, HTTPS, FTP and FTPS (Added in 7.65.2).

Older versions defaulted to all protocols except FILE, SCP and since 7.40.0 SMB and SMBS.

Protocols

All

Example

curl = curl_easy_init();
if(curl) {
  /* pass in the URL from an external source */
  curl_easy_setopt(curl, CURLOPT_URL, argv[1]);

  /* only allow redirects to HTTP and HTTPS URLs */
  curl_easy_setopt(curl, CURLOPT_REDIR_PROTOCOLS_STR, "http,https");

  /* Perform the request */
  curl_easy_perform(curl);
}

Availability

Added in 7.85.0.

Return Value

Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.

See Also

CURLOPT_PROTOCOLS_STR(3),

Referenced By

curl_easy_setopt(3), CURLOPT_PROTOCOLS_STR(3), CURLOPT_REDIR_PROTOCOLS(3).

June 13, 2022 libcurl 7.85.0 curl_easy_setopt options