CURLOPT_HSTSREADFUNCTION(3)

1CURLOPT_HSTSREADFUNCTION(3)         libcurl        CURLOPT_HSTSREADFUNCTION(3)
2
3
4

NAME

6       CURLOPT_HSTSREADFUNCTION - read callback for HSTS hosts
7

SYNOPSIS

9       #include <curl/curl.h>
10
11       struct curl_hstsentry {
12         char *name;
13         size_t namelen;
14         unsigned int includeSubDomains:1;
15         char expire[18]; /* YYYYMMDD HH:MM:SS [null-terminated] */
16       };
17
18       CURLSTScode hstsread(CURL *easy, struct curl_hstsentry *sts, void *clientp);
19
20       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_HSTSREADFUNCTION, hstsread);
21

DESCRIPTION

23       Pass a pointer to your callback function, as the prototype shows above.
24
25       This  callback function gets called by libcurl repeatedly when it popu‐
26       lates the in-memory HSTS cache.
27
28       Set the clientp argument with the CURLOPT_HSTSREADDATA(3) option or  it
29       will be NULL.
30
31       When  this  callback  is invoked, the sts pointer points to a populated
32       struct: Copy the host name to name (no longer than namelen bytes). Make
33       it  null-terminated. Set includeSubDomains to TRUE or FALSE. Set expire
34       to a date stamp or a zero length string for *forever* (wrong date stamp
35       format might cause the name to not get accepted)
36
37       The  callback should return CURLSTS_OK if it returns a name and is pre‐
38       pared to be called again (for another host) or CURLSTS_DONE if  it  has
39       no  entry  to  return. It can also return CURLSTS_FAIL to signal error.
40       Returning CURLSTS_FAIL will stop the transfer from being performed  and
41       make CURLE_ABORTED_BY_CALLBACK get returned.
42
43       This  option does not enable HSTS, you need to use CURLOPT_HSTS_CTRL(3)
44       to do that.
45

DEFAULT

47       NULL - no callback.
48

PROTOCOLS

50       This feature is only used for HTTP(S) transfer.
51

EXAMPLE

53       {
54         /* set HSTS read callback */
55         curl_easy_setopt(curl, CURLOPT_HSTSREADFUNCTION, hstsread);
56
57         /* pass in suitable argument to the callback */
58         curl_easy_setopt(curl, CURLOPT_HSTSREADDATA, &hstspreload[0]);
59
60         result = curl_easy_perform(curl);
61       }
62

AVAILABILITY

64       Added in 7.74.0
65

RETURN VALUE

67       This will return CURLE_OK.
68