curl/docs/libcurl/opts/CURLINFO_CERTINFO.md
Daniel Stenberg 8442c24c9a
CURLINFO: remove 'get' and 'get the' from each short desc
The short descriptions describe the data each info retrieves. The info
itself does not 'get' the data.

This simplifies and shortens the descriptions and make them more
consistent.

Closes #19406
2025-11-08 17:05:55 +01:00

109 lines
2.4 KiB
Markdown

---
c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
SPDX-License-Identifier: curl
Title: CURLINFO_CERTINFO
Section: 3
Source: libcurl
See-also:
- CURLINFO_CAPATH (3)
- curl_easy_getinfo (3)
- curl_easy_setopt (3)
Protocol:
- TLS
TLS-backend:
- OpenSSL
- GnuTLS
- Schannel
- rustls
Added-in: 7.19.1
---
# NAME
CURLINFO_CERTINFO - TLS certificate chain
# SYNOPSIS
~~~c
#include <curl/curl.h>
CURLcode curl_easy_getinfo(CURL *handle, CURLINFO_CERTINFO,
struct curl_certinfo **chainp);
~~~
# DESCRIPTION
Pass a pointer to a *struct curl_certinfo ** and it is set to point to a
struct that holds info about the server's certificate chain, assuming you had
CURLOPT_CERTINFO(3) enabled when the request was made.
~~~c
struct curl_certinfo {
int num_of_certs;
struct curl_slist **certinfo;
};
~~~
The *certinfo* struct member is an array of linked lists of certificate
information. The *num_of_certs* struct member is the number of certificates
which is the number of elements in the array. Each certificate's list has
items with textual information in the format "name:content" such as
"Subject:Foo", "Issuer:Bar", etc. The items in each list varies depending on
the SSL backend and the certificate.
# %PROTOCOLS%
# EXAMPLE
~~~c
int main(void)
{
CURL *curl = curl_easy_init();
if(curl) {
CURLcode res;
curl_easy_setopt(curl, CURLOPT_URL, "https://www.example.com/");
/* connect to any HTTPS site, trusted or not */
curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0L);
curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0L);
curl_easy_setopt(curl, CURLOPT_CERTINFO, 1L);
res = curl_easy_perform(curl);
if(!res) {
int i;
struct curl_certinfo *ci;
res = curl_easy_getinfo(curl, CURLINFO_CERTINFO, &ci);
if(!res) {
printf("%d certs!\n", ci->num_of_certs);
for(i = 0; i < ci->num_of_certs; i++) {
struct curl_slist *slist;
for(slist = ci->certinfo[i]; slist; slist = slist->next)
printf("%s\n", slist->data);
}
}
}
curl_easy_cleanup(curl);
}
}
~~~
See also the *certinfo.c* example.
# HISTORY
GnuTLS support added in 7.42.0. Schannel support added in 7.50.0. mbedTLS
support added in 8.9.0.
# %AVAILABILITY%
# RETURN VALUE
curl_easy_getinfo(3) returns a CURLcode indicating success or error.
CURLE_OK (0) means everything was OK, non-zero means an error occurred, see
libcurl-errors(3).