1/* Simple S/MIME encrypt example */ 2#include <openssl/pem.h> 3#include <openssl/pkcs7.h> 4#include <openssl/err.h> 5 6int main(int argc, char **argv) 7 { 8 BIO *in = NULL, *out = NULL, *tbio = NULL; 9 X509 *rcert = NULL; 10 STACK_OF(X509) *recips = NULL; 11 PKCS7 *p7 = NULL; 12 int ret = 1; 13 14 /* 15 * On OpenSSL 0.9.9 only: 16 * for streaming set PKCS7_STREAM 17 */ 18 int flags = PKCS7_STREAM; 19 20 OpenSSL_add_all_algorithms(); 21 ERR_load_crypto_strings(); 22 23 /* Read in recipient certificate */ 24 tbio = BIO_new_file("signer.pem", "r"); 25 26 if (!tbio) 27 goto err; 28 29 rcert = PEM_read_bio_X509(tbio, NULL, 0, NULL); 30 31 if (!rcert) 32 goto err; 33 34 /* Create recipient STACK and add recipient cert to it */ 35 recips = sk_X509_new_null(); 36 37 if (!recips || !sk_X509_push(recips, rcert)) 38 goto err; 39 40 /* sk_X509_pop_free will free up recipient STACK and its contents 41 * so set rcert to NULL so it isn't freed up twice. 42 */ 43 rcert = NULL; 44 45 /* Open content being encrypted */ 46 47 in = BIO_new_file("encr.txt", "r"); 48 49 if (!in) 50 goto err; 51 52 /* encrypt content */ 53 p7 = PKCS7_encrypt(recips, in, EVP_des_ede3_cbc(), flags); 54 55 if (!p7) 56 goto err; 57 58 out = BIO_new_file("smencr.txt", "w"); 59 if (!out) 60 goto err; 61 62 /* Write out S/MIME message */ 63 if (!SMIME_write_PKCS7(out, p7, in, flags)) 64 goto err; 65 66 ret = 0; 67 68 err: 69 70 if (ret) 71 { 72 fprintf(stderr, "Error Encrypting Data\n"); 73 ERR_print_errors_fp(stderr); 74 } 75 76 if (p7) 77 PKCS7_free(p7); 78 if (rcert) 79 X509_free(rcert); 80 if (recips) 81 sk_X509_pop_free(recips, X509_free); 82 83 if (in) 84 BIO_free(in); 85 if (out) 86 BIO_free(out); 87 if (tbio) 88 BIO_free(tbio); 89 90 return ret; 91 92 } 93