keypair.c

   1 #include <string.h>
   2 #include <unistd.h>
   3 #include <sys/types.h>
   4 #include <pwd.h>
   5 #include <stdio.h>
   6
   7 #include "rnd.h"
   8 #include "die.h"
   9 #include "str.h"
  10 #include "crypto.h"
  11 #include "curve.h"
  12 #include "ioops.h"
  13 #include "config.h"
  14 #include "keypair.h"
  15
  16 void generate_keypair(void)
  17 {
  18         struct passwd *pw = getpwuid(getuid());
  19         unsigned char publickey[crypto_box_pub_key_size];
  20         unsigned char secretkey[crypto_box_sec_key_size];
  21         char file[128];
  22
  23         xmemset(publickey, 0, sizeof(publickey));
  24         xmemset(secretkey, 0, sizeof(secretkey));
  25
  26         curve25519_selftest();
  27
  28         printf("Reading from %s (this may take a while) ...\n",
  29                HIG_ENTROPY_SOURCE);
  30
  31         gen_key_bytes(secretkey, sizeof(secretkey));
  32         crypto_scalarmult_curve25519_base(publickey, secretkey);
  33
  34         slprintf(file, sizeof(file), "%s/%s", pw->pw_dir, FILE_PUBKEY);
  35         write_blob_or_die(file, publickey, sizeof(publickey));
  36         printf("Public key written to %s!\n", file);
  37
  38         slprintf(file, sizeof(file), "%s/%s", pw->pw_dir, FILE_PRIVKEY);
  39         write_blob_or_die(file, secretkey, sizeof(secretkey));
  40         printf("Secret key written to %s!\n", file);
  41
  42         xmemset(publickey, 0, sizeof(publickey));
  43         xmemset(secretkey, 0, sizeof(secretkey));
  44 }
  45
  46 void verify_keypair(void)
  47 {
  48         int result;
  49         struct passwd *pw = getpwuid(getuid());
  50         unsigned char publickey[crypto_box_pub_key_size];
  51         unsigned char publicres[crypto_box_pub_key_size];
  52         unsigned char secretkey[crypto_box_sec_key_size];
  53         char file[128];
  54
  55         curve25519_selftest();
  56
  57         xmemset(publickey, 0, sizeof(publickey));
  58         xmemset(publicres, 0, sizeof(publicres));
  59         xmemset(secretkey, 0, sizeof(secretkey));
  60
  61         slprintf(file, sizeof(file), "%s/%s", pw->pw_dir, FILE_PUBKEY);
  62         read_blob_or_die(file, publickey, sizeof(publickey));
  63
  64         slprintf(file, sizeof(file), "%s/%s", pw->pw_dir, FILE_PRIVKEY);
  65         read_blob_or_die(file, secretkey, sizeof(secretkey));
  66
  67         crypto_scalarmult_curve25519_base(publicres, secretkey);
  68         result = crypto_verify_32(publicres, publickey);
  69
  70         xmemset(publickey, 0, sizeof(publickey));
  71         xmemset(publicres, 0, sizeof(publicres));
  72         xmemset(secretkey, 0, sizeof(secretkey));
  73
  74         if (result)
  75                 panic("Keypair is corrupt! You need to regenerate!\n");
  76 }