usercertinmem.c: add example showing user cert in memory

Relies on CURLOPT_SSL_CTX_FUNCTION, which is OpenSSL specific

docs/examples/Makefile.inc

@@ -5,7 +5,8 @@ check_PROGRAMS = 10-at-a-time anyauthput cookie_interface debug fileupload \
   persistant post-callback postit2 sepheaders simple simplepost simplessl  \
   sendrecv httpcustomheader certinfo chkspeed ftpgetinfo ftp-wildcard \
   smtp-multi simplesmtp smtp-tls rtsp externalsocket resolve \
-  progressfunc pop3s pop3slist imap url2file sftpget ftpsget
+  progressfunc pop3s pop3slist imap url2file sftpget ftpsget \
+  usercertinmem
 
 # These examples require external dependencies that may not be commonly
 # available on POSIX systems, so don't bother attempting to compile them here.

docs/examples/usercertinmem.c

+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 2013, Daniel Stenberg, <daniel@haxx.se>, et al.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution. The terms
+ * are also available at http://curl.haxx.se/docs/copyright.html.
+ *
+ * You may opt to use, copy, modify, merge, publish, distribute and/or sell
+ * copies of the Software, and permit persons to whom the Software is
+ * furnished to do so, under the terms of the COPYING file.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ***************************************************************************/
+/* Example using an in memory PEM user certificate and RSA key to retrieve an
+ * https page.
+ * Written by Ishan SinghLevett, based on Theo Borm's cacertinmem.c.
+ * Note this example does not use a CA certificate, however one should be used
+ * if you want a properly secure connection
+ */
+
+#include <openssl/ssl.h>
+#include <openssl/x509.h>
+#include <openssl/pem.h>
+#include <curl/curl.h>
+#include <stdio.h>
+
+static size_t writefunction(void *ptr, size_t size, size_t nmemb, void *stream)
+{
+  fwrite(ptr,size,nmemb,stream);
+  return(nmemb*size);
+}
+
+static CURLcode sslctx_function(CURL *curl, void *sslctx, void *parm)
+{
+  X509 *cert = NULL;
+  BIO *bio = NULL;
+  BIO *kbio = NULL;
+  RSA *rsa = NULL;
+  int ret;
+
+  const char *mypem = /* www.cacert.org */
+    "-----BEGIN CERTIFICATE-----\n"\
+    "MIIHPTCCBSWgAwIBAgIBADANBgkqhkiG9w0BAQQFADB5MRAwDgYDVQQKEwdSb290\n"\
+    "IENBMR4wHAYDVQQLExVodHRwOi8vd3d3LmNhY2VydC5vcmcxIjAgBgNVBAMTGUNB\n"\
+    "IENlcnQgU2lnbmluZyBBdXRob3JpdHkxITAfBgkqhkiG9w0BCQEWEnN1cHBvcnRA\n"\
+    "Y2FjZXJ0Lm9yZzAeFw0wMzAzMzAxMjI5NDlaFw0zMzAzMjkxMjI5NDlaMHkxEDAO\n"\
+    "BgNVBAoTB1Jvb3QgQ0ExHjAcBgNVBAsTFWh0dHA6Ly93d3cuY2FjZXJ0Lm9yZzEi\n"\
+    "MCAGA1UEAxMZQ0EgQ2VydCBTaWduaW5nIEF1dGhvcml0eTEhMB8GCSqGSIb3DQEJ\n"\
+    "ARYSc3VwcG9ydEBjYWNlcnQub3JnMIICIjANBgkqhkiG9w0BAQEFAAOCAg8AMIIC\n"\
+    "CgKCAgEAziLA4kZ97DYoB1CW8qAzQIxL8TtmPzHlawI229Z89vGIj053NgVBlfkJ\n"\
+    "8BLPRoZzYLdufujAWGSuzbCtRRcMY/pnCujW0r8+55jE8Ez64AO7NV1sId6eINm6\n"\
+    "zWYyN3L69wj1x81YyY7nDl7qPv4coRQKFWyGhFtkZip6qUtTefWIonvuLwphK42y\n"\
+    "fk1WpRPs6tqSnqxEQR5YYGUFZvjARL3LlPdCfgv3ZWiYUQXw8wWRBB0bF4LsyFe7\n"\
+    "w2t6iPGwcswlWyCR7BYCEo8y6RcYSNDHBS4CMEK4JZwFaz+qOqfrU0j36NK2B5jc\n"\
+    "G8Y0f3/JHIJ6BVgrCFvzOKKrF11myZjXnhCLotLddJr3cQxyYN/Nb5gznZY0dj4k\n"\
+    "epKwDpUeb+agRThHqtdB7Uq3EvbXG4OKDy7YCbZZ16oE/9KTfWgu3YtLq1i6L43q\n"\
+    "laegw1SJpfvbi1EinbLDvhG+LJGGi5Z4rSDTii8aP8bQUWWHIbEZAWV/RRyH9XzQ\n"\
+    "QUxPKZgh/TMfdQwEUfoZd9vUFBzugcMd9Zi3aQaRIt0AUMyBMawSB3s42mhb5ivU\n"\
+    "fslfrejrckzzAeVLIL+aplfKkQABi6F1ITe1Yw1nPkZPcCBnzsXWWdsC4PDSy826\n"\
+    "YreQQejdIOQpvGQpQsgi3Hia/0PsmBsJUUtaWsJx8cTLc6nloQsCAwEAAaOCAc4w\n"\
+    "ggHKMB0GA1UdDgQWBBQWtTIb1Mfz4OaO873SsDrusjkY0TCBowYDVR0jBIGbMIGY\n"\
+    "gBQWtTIb1Mfz4OaO873SsDrusjkY0aF9pHsweTEQMA4GA1UEChMHUm9vdCBDQTEe\n"\
+    "MBwGA1UECxMVaHR0cDovL3d3dy5jYWNlcnQub3JnMSIwIAYDVQQDExlDQSBDZXJ0\n"\
+    "IFNpZ25pbmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcNAQkBFhJzdXBwb3J0QGNhY2Vy\n"\
+    "dC5vcmeCAQAwDwYDVR0TAQH/BAUwAwEB/zAyBgNVHR8EKzApMCegJaAjhiFodHRw\n"\
+    "czovL3d3dy5jYWNlcnQub3JnL3Jldm9rZS5jcmwwMAYJYIZIAYb4QgEEBCMWIWh0\n"\
+    "dHBzOi8vd3d3LmNhY2VydC5vcmcvcmV2b2tlLmNybDA0BglghkgBhvhCAQgEJxYl\n"\
+    "aHR0cDovL3d3dy5jYWNlcnQub3JnL2luZGV4LnBocD9pZD0xMDBWBglghkgBhvhC\n"\
+    "AQ0ESRZHVG8gZ2V0IHlvdXIgb3duIGNlcnRpZmljYXRlIGZvciBGUkVFIGhlYWQg\n"\
+    "b3ZlciB0byBodHRwOi8vd3d3LmNhY2VydC5vcmcwDQYJKoZIhvcNAQEEBQADggIB\n"\
+    "ACjH7pyCArpcgBLKNQodgW+JapnM8mgPf6fhjViVPr3yBsOQWqy1YPaZQwGjiHCc\n"\
+    "nWKdpIevZ1gNMDY75q1I08t0AoZxPuIrA2jxNGJARjtT6ij0rPtmlVOKTV39O9lg\n"\
+    "18p5aTuxZZKmxoGCXJzN600BiqXfEVWqFcofN8CCmHBh22p8lqOOLlQ+TyGpkO/c\n"\
+    "gr/c6EWtTZBzCDyUZbAEmXZ/4rzCahWqlwQ3JNgelE5tDlG+1sSPypZt90Pf6DBl\n"\
+    "Jzt7u0NDY8RD97LsaMzhGY4i+5jhe1o+ATc7iwiwovOVThrLm82asduycPAtStvY\n"\
+    "sONvRUgzEv/+PDIqVPfE94rwiCPCR/5kenHA0R6mY7AHfqQv0wGP3J8rtsYIqQ+T\n"\
+    "SCX8Ev2fQtzzxD72V7DX3WnRBnc0CkvSyqD/HMaMyRa+xMwyN2hzXwj7UfdJUzYF\n"\
+    "CpUCTPJ5GhD22Dp1nPMd8aINcGeGG7MW9S/lpOt5hvk9C8JzC6WZrG/8Z7jlLwum\n"\
+    "GCSNe9FINSkYQKyTYOGWhlC0elnYjyELn8+CkcY7v2vcB5G5l1YjqrZslMZIBjzk\n"\
+    "zk6q5PYvCdxTby78dOs6Y5nCpqyJvKeyRKANihDjbPIky/qbn3BHLt4Ui9SyIAmW\n"\
+    "omTxJBzcoTWcFbLUvFUufQb1nA5V9FrWk9p2rSVzTMVD\n"\
+    "-----END CERTIFICATE-----\n";
+
+/*replace the XXX with the actual RSA key*/
+  const char *mykey =
+    "-----BEGIN RSA PRIVATE KEY-----\n"\
+    "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX\n"\
+    "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX\n"\
+    "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX\n"\
+    "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX\n"\
+    "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX\n"\
+    "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX\n"\
+    "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX\n"\
+    "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX\n"\
+    "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX\n"\
+    "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX\n"\
+    "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX\n"\
+    "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX\n"\
+    "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX\n"\
+    "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX\n"\
+    "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX\n"\
+    "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX\n"\
+    "-----END RSA PRIVATE KEY-----\n";
+
+  (void)curl; /* avoid warnings */
+  (void)parm; /* avoid warnings */
+
+  /* get a BIO */
+  bio = BIO_new_mem_buf((char *)mypem, -1);
+
+  if (bio == NULL) {
+    printf("BIO_new_mem_buf failed\n");
+  }
+
+  /* use it to read the PEM formatted certificate from memory into an X509
+   * structure that SSL can use
+   */
+  cert = PEM_read_bio_X509(bio, NULL, 0, NULL);
+  if (cert == NULL) {
+    printf("PEM_read_bio_X509 failed...\n");
+  }
+
+  /*tell SSL to use the X509 certificate*/
+  ret = SSL_CTX_use_certificate((SSL_CTX*)sslctx, cert);
+  if (ret != 1) {
+    printf("Use certificate failed\n");
+  }
+
+  /*create a bio for the RSA key*/
+  kbio = BIO_new_mem_buf((char *)mykey, -1);
+  if (kbio == NULL) {
+    printf("BIO_new_mem_buf failed\n");
+  }
+
+  /*read the key bio into an RSA object*/
+  rsa = PEM_read_bio_RSAPrivateKey(kbio, NULL, 0, NULL);
+  if (rsa == NULL) {
+    printf("Failed to create key bio\n");
+  }
+
+  /*tell SSL to use the RSA key from memory*/
+  ret = SSL_CTX_use_RSAPrivateKey((SSL_CTX*)sslctx, rsa);
+  if (ret != 1) {
+    printf("Use Key failed\n");
+  }
+
+
+  /* all set to go */
+  return CURLE_OK ;
+}
+
+int main(void)
+{
+  CURL *ch;
+  CURLcode rv;
+
+  rv = curl_global_init(CURL_GLOBAL_ALL);
+  ch = curl_easy_init();
+  rv = curl_easy_setopt(ch,CURLOPT_VERBOSE, 0L);
+  rv = curl_easy_setopt(ch,CURLOPT_HEADER, 0L);
+  rv = curl_easy_setopt(ch,CURLOPT_NOPROGRESS, 1L);
+  rv = curl_easy_setopt(ch,CURLOPT_NOSIGNAL, 1L);
+  rv = curl_easy_setopt(ch,CURLOPT_WRITEFUNCTION, *writefunction);
+  rv = curl_easy_setopt(ch,CURLOPT_WRITEDATA, stdout);
+  rv = curl_easy_setopt(ch,CURLOPT_HEADERFUNCTION, *writefunction);
+  rv = curl_easy_setopt(ch,CURLOPT_WRITEHEADER, stderr);
+  rv = curl_easy_setopt(ch,CURLOPT_SSLCERTTYPE,"PEM");
+
+  /* both VERIFYPEER and VERIFYHOST are set to 0 in this case because there is
+     no CA certificate*/
+
+  rv = curl_easy_setopt(ch,CURLOPT_SSL_VERIFYPEER, 0L);
+  rv = curl_easy_setopt(ch,CURLOPT_SSL_VERIFYHOST, 0L);
+  rv = curl_easy_setopt(ch, CURLOPT_URL, "https://www.example.com/");
+  rv = curl_easy_setopt(ch, CURLOPT_SSLKEYTYPE, "PEM");
+
+  /* first try: retrieve page without user certificate and key -> will fail
+   */
+  rv = curl_easy_perform(ch);
+  if (rv==CURLE_OK) {
+    printf("*** transfer succeeded ***\n");
+  }
+  else {
+    printf("*** transfer failed ***\n");
+  }
+
+  /* second try: retrieve page using user certificate and key -> will succeed
+   * load the certificate and key by installing a function doing the necessary
+   * "modifications" to the SSL CONTEXT just before link init
+   */
+  rv = curl_easy_setopt(ch,CURLOPT_SSL_CTX_FUNCTION, *sslctx_function);
+  rv = curl_easy_perform(ch);
+  if (rv==CURLE_OK) {
+    printf("*** transfer succeeded ***\n");
+  }
+  else {
+    printf("*** transfer failed ***\n");
+  }
+
+  curl_easy_cleanup(ch);
+  curl_global_cleanup();
+  return rv;
+}