1 /* 2 * Copyright 2008-2023 The OpenSSL Project Authors. All Rights Reserved. 3 * 4 * Licensed under the Apache License 2.0 (the "License"). You may not use 5 * this file except in compliance with the License. You can obtain a copy 6 * in the file LICENSE in the source distribution or at 7 * https://www.openssl.org/source/license.html 8 */ 9 10 /* S/MIME signing example: 2 signers */ 11 #include <openssl/pem.h> 12 #include <openssl/cms.h> 13 #include <openssl/err.h> 14 15 int main(int argc, char **argv) 16 { 17 BIO *in = NULL, *out = NULL, *tbio = NULL; 18 X509 *scert = NULL, *scert2 = NULL; 19 EVP_PKEY *skey = NULL, *skey2 = NULL; 20 CMS_ContentInfo *cms = NULL; 21 int ret = EXIT_FAILURE; 22 23 OpenSSL_add_all_algorithms(); 24 ERR_load_crypto_strings(); 25 26 tbio = BIO_new_file("signer.pem", "r"); 27 28 if (!tbio) 29 goto err; 30 31 scert = PEM_read_bio_X509(tbio, NULL, 0, NULL); 32 33 if (BIO_reset(tbio) < 0) 34 goto err; 35 36 skey = PEM_read_bio_PrivateKey(tbio, NULL, 0, NULL); 37 38 BIO_free(tbio); 39 40 tbio = BIO_new_file("signer2.pem", "r"); 41 42 if (!tbio) 43 goto err; 44 45 scert2 = PEM_read_bio_X509(tbio, NULL, 0, NULL); 46 47 if (BIO_reset(tbio) < 0) 48 goto err; 49 50 skey2 = PEM_read_bio_PrivateKey(tbio, NULL, 0, NULL); 51 52 if (!scert2 || !skey2) 53 goto err; 54 55 in = BIO_new_file("sign.txt", "r"); 56 57 if (!in) 58 goto err; 59 60 cms = CMS_sign(NULL, NULL, NULL, in, CMS_STREAM | CMS_PARTIAL); 61 62 if (!cms) 63 goto err; 64 65 /* Add each signer in turn */ 66 67 if (!CMS_add1_signer(cms, scert, skey, NULL, 0)) 68 goto err; 69 70 if (!CMS_add1_signer(cms, scert2, skey2, NULL, 0)) 71 goto err; 72 73 out = BIO_new_file("smout.txt", "w"); 74 if (!out) 75 goto err; 76 77 /* NB: content included and finalized by SMIME_write_CMS */ 78 79 if (!SMIME_write_CMS(out, cms, in, CMS_STREAM)) 80 goto err; 81 82 printf("Signing Successful\n"); 83 84 ret = EXIT_SUCCESS; 85 err: 86 if (ret != EXIT_SUCCESS) { 87 fprintf(stderr, "Error Signing Data\n"); 88 ERR_print_errors_fp(stderr); 89 } 90 91 CMS_ContentInfo_free(cms); 92 X509_free(scert); 93 EVP_PKEY_free(skey); 94 X509_free(scert2); 95 EVP_PKEY_free(skey2); 96 BIO_free(in); 97 BIO_free(out); 98 BIO_free(tbio); 99 return ret; 100 } 101