CMS compressed data examples.

demos/cms/cms_comp.c

+/* Simple S/MIME compress example */
+#include <openssl/pem.h>
+#include <openssl/cms.h>
+#include <openssl/err.h>
+
+int main(int argc, char **argv)
+	{
+	BIO *in = NULL, *out = NULL;
+	CMS_ContentInfo *cms = NULL;
+	int ret = 1;
+
+	/*
+	 * On OpenSSL 0.9.9 only:
+	 * for streaming set CMS_STREAM
+	 */
+	int flags = CMS_STREAM;
+
+	OpenSSL_add_all_algorithms();
+	ERR_load_crypto_strings();
+
+	/* Open content being compressed */
+
+	in = BIO_new_file("comp.txt", "r");
+
+	if (!in)
+		goto err;
+
+	/* compress content */
+	cms = CMS_compress(in, NID_zlib_compression, flags);
+
+	if (!cms)
+		goto err;
+
+	out = BIO_new_file("smcomp.txt", "w");
+	if (!out)
+		goto err;
+
+	/* Write out S/MIME message */
+	if (!SMIME_write_CMS(out, cms, in, flags))
+		goto err;
+
+	ret = 0;
+
+	err:
+
+	if (ret)
+		{
+		fprintf(stderr, "Error Compressing Data\n");
+		ERR_print_errors_fp(stderr);
+		}
+
+	if (cms)
+		CMS_ContentInfo_free(cms);
+	if (in)
+		BIO_free(in);
+	if (out)
+		BIO_free(out);
+
+	return ret;
+
+	}

demos/cms/cms_uncomp.c

+/* Simple S/MIME uncompression example */
+#include <openssl/pem.h>
+#include <openssl/cms.h>
+#include <openssl/err.h>
+
+int main(int argc, char **argv)
+	{
+	BIO *in = NULL, *out = NULL;
+	CMS_ContentInfo *cms = NULL;
+	int ret = 1;
+
+	OpenSSL_add_all_algorithms();
+	ERR_load_crypto_strings();
+
+	/* Open compressed content */
+
+	in = BIO_new_file("smcomp.txt", "r");
+
+	if (!in)
+		goto err;
+
+	/* Sign content */
+	cms = SMIME_read_CMS(in, NULL);
+
+	if (!cms)
+		goto err;
+
+	out = BIO_new_file("smuncomp.txt", "w");
+	if (!out)
+		goto err;
+
+	/* Uncompress S/MIME message */
+	if (!CMS_uncompress(cms, out, NULL, 0))
+		goto err;
+
+	ret = 0;
+
+	err:
+
+	if (ret)
+		{
+		fprintf(stderr, "Error Uncompressing Data\n");
+		ERR_print_errors_fp(stderr);
+		}
+
+	if (cms)
+		CMS_ContentInfo_free(cms);
+
+	if (in)
+		BIO_free(in);
+	if (out)
+		BIO_free(out);
+
+	return ret;
+
+	}

demos/cms/comp.txt

+Content-type: text/plain
+
+Some Text To be Compressed
+Some Text To be Compressed
+Some Text To be Compressed
+Some Text To be Compressed
+Some Text To be Compressed
+Some Text To be Compressed
+Some Text To be Compressed
+Some Text To be Compressed
+Some Text To be Compressed
+Some Text To be Compressed
+Some Text To be Compressed
+Some Text To be Compressed
+Some Text To be Compressed
+Some Text To be Compressed
+Some Text To be Compressed
+Some Text To be Compressed
+Some Text To be Compressed
+Some Text To be Compressed
+Some Text To be Compressed
+Some Text To be Compressed