1 files changed, 167 insertions, 0 deletions
diff --git a/tls-cli.c b/tls-cli.c
new file mode 100644
index 000000000..15ad04435
--- /dev/null
+++ b/tls-cli.c
@@ -0,0 +1,167 @@
+/* This example code is placed in the public domain. */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+#include <gnutls/gnutls.h>
+#include <gnutls/x509.h>
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <arpa/inet.h>
+#include <netinet/in.h>
+#include <unistd.h>
+
+#include <errno.h>
+
+#define CHECK(x) assert((x) >= 0)
+
+#define MAX_BUF 1024
+#define MSG "Hello TLS"
+
+static int tcp_connect(void)
+{
+    const char * PORT = "5556";
+    const char * SERVER = "127.0.0.1";
+    int err, sd;
+    struct sockaddr_in sa;
+
+    /* connects to server
+     */
+    sd = socket(AF_INET, SOCK_STREAM, 0);
+
+    memset(&sa, '\0', sizeof(sa));
+    sa.sin_family = AF_INET;
+    sa.sin_port = htons(atoi(PORT));
+    inet_pton(AF_INET, SERVER, &sa.sin_addr);
+
+    err = connect(sd, (struct sockaddr *)&sa, sizeof(sa));
+    if (err < 0)
+    {
+        fprintf(stderr, "Connect error\n");
+        exit(1);
+    }
+
+    return sd;
+}
+
+static void tcp_close(int sd)
+{
+    shutdown(sd, SHUT_RDWR); /* no more receptions */
+    close(sd);
+}
+
+int main(void)
+{
+    int ret, sd, ii;
+    gnutls_session_t session;
+    char buffer[MAX_BUF + 1], *desc;
+    gnutls_datum_t out;
+    int type;
+    unsigned status;
+    gnutls_certificate_credentials_t xcred;
+
+    if (gnutls_check_version("3.4.6") == NULL)
+    {
+        fprintf(stderr, "GnuTLS 3.4.6 or later is required for this example\n");
+        exit(1);
+    }
+
+    /* for backwards compatibility with gnutls < 3.3.0 */
+    CHECK(gnutls_global_init());
+
+    /* X509 stuff */
+    CHECK(gnutls_certificate_allocate_credentials(&xcred));
+
+    gnutls_certificate_set_x509_key_file(xcred, "client-cert.pem", "client-key.pem", GNUTLS_X509_FMT_PEM);
+
+    CHECK(gnutls_certificate_set_x509_trust_file(xcred, "ca-cert.pem", GNUTLS_X509_FMT_PEM));
+
+    /* Initialize TLS session */
+    CHECK(gnutls_init(&session, GNUTLS_CLIENT));
+
+    /* It is recommended to use the default priorities */
+    CHECK(gnutls_set_default_priority(session));
+
+    /* put the x509 credentials to the current session */
+    CHECK(gnutls_credentials_set(session, GNUTLS_CRD_CERTIFICATE, xcred));
+
+    sd = tcp_connect();
+
+    gnutls_transport_set_int(session, sd);
+    gnutls_handshake_set_timeout(session, GNUTLS_DEFAULT_HANDSHAKE_TIMEOUT);
+
+    /* Perform the TLS handshake */
+    do
+    {
+        ret = gnutls_handshake(session);
+    } while (ret < 0 && gnutls_error_is_fatal(ret) == 0);
+    if (ret < 0)
+    {
+        if (ret == GNUTLS_E_CERTIFICATE_VERIFICATION_ERROR)
+        {
+            /* check certificate verification status */
+            type = gnutls_certificate_type_get(session);
+            status = gnutls_session_get_verify_cert_status(session);
+            CHECK(gnutls_certificate_verification_status_print(status, type, &out, 0));
+            printf("cert verify output: %s\n", out.data);
+            gnutls_free(out.data);
+        }
+        fprintf(stderr, "*** Handshake failed: %s\n", gnutls_strerror(ret));
+        goto end;
+    }
+    else
+    {
+        desc = gnutls_session_get_desc(session);
+        printf("- Session info: %s\n", desc);
+        gnutls_free(desc);
+    }
+
+    /* send data */
+    CHECK(gnutls_record_send(session, MSG, strlen(MSG)));
+
+    ret = gnutls_record_recv(session, buffer, MAX_BUF);
+    if (ret == 0)
+    {
+        printf("- Peer has closed the TLS connection\n");
+        goto end;
+    }
+    else if (ret < 0 && gnutls_error_is_fatal(ret) == 0)
+    {
+        fprintf(stderr, "*** Warning: %s\n", gnutls_strerror(ret));
+    }
+    else if (ret < 0)
+    {
+        fprintf(stderr, "*** Error: %s\n", gnutls_strerror(ret));
+        goto end;
+    }
+
+    if (ret > 0)
+    {
+        printf("- Received %d bytes: ", ret);
+        for (ii = 0; ii < ret; ii++)
+        {
+            fputc(buffer[ii], stdout);
+        }
+        fputs("\n", stdout);
+    }
+
+    CHECK(gnutls_bye(session, GNUTLS_SHUT_RDWR));
+
+end:
+
+    tcp_close(sd);
+
+    gnutls_deinit(session);
+
+    gnutls_certificate_free_credentials(xcred);
+
+    gnutls_global_deinit();
+
+    return 0;
+}