demos/maurice/example1.c

   1 /* NOCW */
   2 /*
   3         Please read the README file for condition of use, before
   4         using this software.
   5
   6         Maurice Gittens  <mgittens@gits.nl>   January 1997
   7 */
   8
   9 #include <unistd.h>
  10 #include <stdio.h>
  11 #include <netinet/in.h>
  12 #include <fcntl.h>
  13 #include <strings.h>
  14 #include <stdlib.h>
  15
  16 #include <openssl/rsa.h>
  17 #include <openssl/evp.h>
  18 #include <openssl/objects.h>
  19 #include <openssl/x509.h>
  20 #include <openssl/err.h>
  21 #include <openssl/pem.h>
  22 #include <openssl/ssl.h>
  23
  24 #include "loadkeys.h"
  25
  26 #define PUBFILE   "cert.pem"
  27 #define PRIVFILE  "privkey.pem"
  28
  29 #define STDIN     0
  30 #define STDOUT    1
  31
  32 void main_encrypt(void);
  33 void main_decrypt(void);
  34
  35 static const char *usage = "Usage: example1 [-d]\n";
  36
  37 int main(int argc, char *argv[])
  38 {
  39
  40         ERR_load_crypto_strings();
  41
  42         if ((argc == 1))
  43         {
  44                 main_encrypt();
  45         }
  46         else if ((argc == 2) && !strcmp(argv[1],"-d"))
  47         {
  48                 main_decrypt();
  49         }
  50         else
  51         {
  52                 printf("%s",usage);
  53                 exit(1);
  54         }
  55
  56         return 0;
  57 }
  58
  59 void main_encrypt(void)
  60 {
  61         unsigned int ebuflen;
  62         EVP_CIPHER_CTX ectx;
  63         unsigned char iv[EVP_MAX_IV_LENGTH];
  64         unsigned char *ekey[1];
  65         int readlen;
  66         int ekeylen, net_ekeylen;
  67         EVP_PKEY *pubKey[1];
  68         char buf[512];
  69         char ebuf[512];
  70
  71         memset(iv, '\0', sizeof(iv));
  72
  73         pubKey[0] = ReadPublicKey(PUBFILE);
  74
  75         if(!pubKey)
  76         {
  77            fprintf(stderr,"Error: can't load public key");
  78            exit(1);
  79         }
  80
  81         ekey[0] = malloc(EVP_PKEY_size(pubKey[0]));
  82         if (!ekey[0])
  83         {
  84            EVP_PKEY_free(pubKey[0]);
  85            perror("malloc");
  86            exit(1);
  87         }
  88
  89         EVP_SealInit(&ectx,
  90                    EVP_des_ede3_cbc(),
  91                    ekey,
  92                    &ekeylen,
  93                    iv,
  94                    pubKey,
  95                    1);
  96
  97         net_ekeylen = htonl(ekeylen);
  98         write(STDOUT, (char*)&net_ekeylen, sizeof(net_ekeylen));
  99         write(STDOUT, ekey[0], ekeylen);
 100         write(STDOUT, iv, sizeof(iv));
 101
 102         while(1)
 103         {
 104                 readlen = read(STDIN, buf, sizeof(buf));
 105
 106                 if (readlen <= 0)
 107                 {
 108                    if (readlen < 0)
 109                         perror("read");
 110
 111                    break;
 112                 }
 113
 114                 EVP_SealUpdate(&ectx, ebuf, &ebuflen, buf, readlen);
 115
 116                 write(STDOUT, ebuf, ebuflen);
 117         }
 118
 119         EVP_SealFinal(&ectx, ebuf, &ebuflen);
 120
 121         write(STDOUT, ebuf, ebuflen);
 122
 123         EVP_PKEY_free(pubKey[0]);
 124         free(ekey[0]);
 125 }
 126
 127 void main_decrypt(void)
 128 {
 129         char buf[520];
 130         char ebuf[512];
 131         unsigned int buflen;
 132         EVP_CIPHER_CTX ectx;
 133         unsigned char iv[EVP_MAX_IV_LENGTH];
 134         unsigned char *encryptKey;
 135         unsigned int ekeylen;
 136         EVP_PKEY *privateKey;
 137
 138         memset(iv, '\0', sizeof(iv));
 139
 140         privateKey = ReadPrivateKey(PRIVFILE);
 141         if (!privateKey)
 142         {
 143                 fprintf(stderr, "Error: can't load private key");
 144                 exit(1);
 145         }
 146
 147         read(STDIN, &ekeylen, sizeof(ekeylen));
 148         ekeylen = ntohl(ekeylen);
 149
 150         if (ekeylen != EVP_PKEY_size(privateKey))
 151         {
 152                 EVP_PKEY_free(privateKey);
 153                 fprintf(stderr, "keylength mismatch");
 154                 exit(1);
 155         }
 156
 157         encryptKey = malloc(sizeof(char) * ekeylen);
 158         if (!encryptKey)
 159         {
 160                 EVP_PKEY_free(privateKey);
 161                 perror("malloc");
 162                 exit(1);
 163         }
 164
 165         read(STDIN, encryptKey, ekeylen);
 166         read(STDIN, iv, sizeof(iv));
 167         EVP_OpenInit(&ectx,
 168                    EVP_des_ede3_cbc(),
 169                    encryptKey,
 170                    ekeylen,
 171                    iv,
 172                    privateKey);
 173
 174         while(1)
 175         {
 176                 int readlen = read(STDIN, ebuf, sizeof(ebuf));
 177
 178                 if (readlen <= 0)
 179                 {
 180                         if (readlen < 0)
 181                                 perror("read");
 182
 183                         break;
 184                 }
 185
 186                 EVP_OpenUpdate(&ectx, buf, &buflen, ebuf, readlen);
 187                 write(STDOUT, buf, buflen);
 188         }
 189
 190         EVP_OpenFinal(&ectx, buf, &buflen);
 191
 192         write(STDOUT, buf, buflen);
 193
 194         EVP_PKEY_free(privateKey);
 195         free(encryptKey);
 196 }
 197
 198