CURLOPT_CAINFO.3 3.8 KB

1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071727374757677787980818283848586878889909192
  1. .\" **************************************************************************
  2. .\" * _ _ ____ _
  3. .\" * Project ___| | | | _ \| |
  4. .\" * / __| | | | |_) | |
  5. .\" * | (__| |_| | _ <| |___
  6. .\" * \___|\___/|_| \_\_____|
  7. .\" *
  8. .\" * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
  9. .\" *
  10. .\" * This software is licensed as described in the file COPYING, which
  11. .\" * you should have received as part of this distribution. The terms
  12. .\" * are also available at https://curl.se/docs/copyright.html.
  13. .\" *
  14. .\" * You may opt to use, copy, modify, merge, publish, distribute and/or sell
  15. .\" * copies of the Software, and permit persons to whom the Software is
  16. .\" * furnished to do so, under the terms of the COPYING file.
  17. .\" *
  18. .\" * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  19. .\" * KIND, either express or implied.
  20. .\" *
  21. .\" * SPDX-License-Identifier: curl
  22. .\" *
  23. .\" **************************************************************************
  24. .\"
  25. .TH CURLOPT_CAINFO 3 "January 02, 2023" "libcurl 7.88.1" "curl_easy_setopt options"
  26. .SH NAME
  27. CURLOPT_CAINFO \- path to Certificate Authority (CA) bundle
  28. .SH SYNOPSIS
  29. .nf
  30. #include <curl/curl.h>
  31. CURLcode curl_easy_setopt(CURL *handle, CURLOPT_CAINFO, char *path);
  32. .fi
  33. .SH DESCRIPTION
  34. Pass a char * to a null-terminated string naming a file holding one or more
  35. certificates to verify the peer with.
  36. If \fICURLOPT_SSL_VERIFYPEER(3)\fP is zero and you avoid verifying the
  37. server's certificate, \fICURLOPT_CAINFO(3)\fP need not even indicate an
  38. accessible file.
  39. This option is by default set to the system path where libcurl's CA
  40. certificate bundle is assumed to be stored, as established at build time.
  41. If curl is built against the NSS SSL library, the NSS PEM PKCS#11 module
  42. (libnsspem.so) needs to be available for this option to work properly.
  43. Starting with curl 7.55.0, if both \fICURLOPT_CAINFO(3)\fP and
  44. \fICURLOPT_CAPATH(3)\fP are unset, NSS-linked libcurl tries to load
  45. libnssckbi.so, which contains a more comprehensive set of trust information
  46. than supported by nss-pem, because libnssckbi.so also includes information
  47. about distrusted certificates.
  48. (iOS and macOS) When curl uses Secure Transport this option is supported. If
  49. the option is not set, then curl will use the certificates in the system and
  50. user Keychain to verify the peer.
  51. (Schannel) This option is supported for Schannel in Windows 7 or later but we
  52. recommend not using it until Windows 8 since it works better starting then.
  53. If the option is not set, then curl will use the certificates in the Windows'
  54. store of root certificates (the default for Schannel).
  55. The application does not have to keep the string around after setting this
  56. option.
  57. The default value for this can be figured out with \fICURLINFO_CAINFO(3)\fP.
  58. .SH DEFAULT
  59. Built-in system specific. When curl is built with Secure Transport or
  60. Schannel, this option is not set by default.
  61. .SH PROTOCOLS
  62. All TLS based protocols: HTTPS, FTPS, IMAPS, POP3S, SMTPS etc.
  63. .SH EXAMPLE
  64. .nf
  65. CURL *curl = curl_easy_init();
  66. if(curl) {
  67. curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
  68. curl_easy_setopt(curl, CURLOPT_CAINFO, "/etc/certs/cabundle.pem");
  69. ret = curl_easy_perform(curl);
  70. curl_easy_cleanup(curl);
  71. }
  72. .fi
  73. .SH AVAILABILITY
  74. For the SSL engines that do not support certificate files the
  75. \fICURLOPT_CAINFO(3)\fP option is ignored. Schannel support added in libcurl
  76. 7.60.
  77. .SH RETURN VALUE
  78. Returns CURLE_OK if the option is supported, CURLE_UNKNOWN_OPTION if not, or
  79. CURLE_OUT_OF_MEMORY if there was insufficient heap space.
  80. .SH "SEE ALSO"
  81. .BR CURLOPT_CAINFO_BLOB "(3), " CURLOPT_CAPATH "(3), "
  82. .BR CURLOPT_SSL_VERIFYPEER "(3), " CURLOPT_SSL_VERIFYHOST "(3), "
  83. .BR CURLINFO_CAINFO "(3), " CURLOPT_CA_CACHE_TIMEOUT "(3), "