crypto/pkcs12/p12_key.c

   1 /*
   2  * Copyright 1999-2016 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the OpenSSL license (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 #include <stdio.h>
  11 #include "internal/cryptlib.h"
  12 #include <openssl/pkcs12.h>
  13 #include <openssl/bn.h>
  14
  15 /* Uncomment out this line to get debugging info about key generation */
  16 /*
  17  * #define OPENSSL_DEBUG_KEYGEN
  18  */
  19 #ifdef OPENSSL_DEBUG_KEYGEN
  20 # include <openssl/bio.h>
  21 extern BIO *bio_err;
  22 void h__dump(unsigned char *p, int len);
  23 #endif
  24
  25 /* PKCS12 compatible key/IV generation */
  26 #ifndef min
  27 # define min(a,b) ((a) < (b) ? (a) : (b))
  28 #endif
  29
  30 int PKCS12_key_gen_asc(const char *pass, int passlen, unsigned char *salt,
  31                        int saltlen, int id, int iter, int n,
  32                        unsigned char *out, const EVP_MD *md_type)
  33 {
  34     int ret;
  35     unsigned char *unipass;
  36     int uniplen;
  37
  38     if (!pass) {
  39         unipass = NULL;
  40         uniplen = 0;
  41     } else if (!OPENSSL_asc2uni(pass, passlen, &unipass, &uniplen)) {
  42         PKCS12err(PKCS12_F_PKCS12_KEY_GEN_ASC, ERR_R_MALLOC_FAILURE);
  43         return 0;
  44     }
  45     ret = PKCS12_key_gen_uni(unipass, uniplen, salt, saltlen,
  46                              id, iter, n, out, md_type);
  47     if (ret <= 0)
  48         return 0;
  49     OPENSSL_clear_free(unipass, uniplen);
  50     return ret;
  51 }
  52
  53 int PKCS12_key_gen_uni(unsigned char *pass, int passlen, unsigned char *salt,
  54                        int saltlen, int id, int iter, int n,
  55                        unsigned char *out, const EVP_MD *md_type)
  56 {
  57     unsigned char *B = NULL, *D = NULL, *I = NULL, *p = NULL, *Ai = NULL;
  58     int Slen, Plen, Ilen, Ijlen;
  59     int i, j, u, v;
  60     int ret = 0;
  61     BIGNUM *Ij = NULL, *Bpl1 = NULL; /* These hold Ij and B + 1 */
  62     EVP_MD_CTX *ctx = NULL;
  63 #ifdef  OPENSSL_DEBUG_KEYGEN
  64     unsigned char *tmpout = out;
  65     int tmpn = n;
  66 #endif
  67
  68     ctx = EVP_MD_CTX_new();
  69     if (ctx == NULL)
  70         goto err;
  71
  72 #ifdef  OPENSSL_DEBUG_KEYGEN
  73     fprintf(stderr, "KEYGEN DEBUG\n");
  74     fprintf(stderr, "ID %d, ITER %d\n", id, iter);
  75     fprintf(stderr, "Password (length %d):\n", passlen);
  76     h__dump(pass, passlen);
  77     fprintf(stderr, "Salt (length %d):\n", saltlen);
  78     h__dump(salt, saltlen);
  79 #endif
  80     v = EVP_MD_block_size(md_type);
  81     u = EVP_MD_size(md_type);
  82     if (u < 0 || v <= 0)
  83         goto err;
  84     D = OPENSSL_malloc(v);
  85     Ai = OPENSSL_malloc(u);
  86     B = OPENSSL_malloc(v + 1);
  87     Slen = v * ((saltlen + v - 1) / v);
  88     if (passlen)
  89         Plen = v * ((passlen + v - 1) / v);
  90     else
  91         Plen = 0;
  92     Ilen = Slen + Plen;
  93     I = OPENSSL_malloc(Ilen);
  94     Ij = BN_new();
  95     Bpl1 = BN_new();
  96     if (D == NULL || Ai == NULL || B == NULL || I == NULL || Ij == NULL
  97             || Bpl1 == NULL)
  98         goto err;
  99     for (i = 0; i < v; i++)
 100         D[i] = id;
 101     p = I;
 102     for (i = 0; i < Slen; i++)
 103         *p++ = salt[i % saltlen];
 104     for (i = 0; i < Plen; i++)
 105         *p++ = pass[i % passlen];
 106     for (;;) {
 107         if (!EVP_DigestInit_ex(ctx, md_type, NULL)
 108             || !EVP_DigestUpdate(ctx, D, v)
 109             || !EVP_DigestUpdate(ctx, I, Ilen)
 110             || !EVP_DigestFinal_ex(ctx, Ai, NULL))
 111             goto err;
 112         for (j = 1; j < iter; j++) {
 113             if (!EVP_DigestInit_ex(ctx, md_type, NULL)
 114                 || !EVP_DigestUpdate(ctx, Ai, u)
 115                 || !EVP_DigestFinal_ex(ctx, Ai, NULL))
 116                 goto err;
 117         }
 118         memcpy(out, Ai, min(n, u));
 119         if (u >= n) {
 120 #ifdef OPENSSL_DEBUG_KEYGEN
 121             fprintf(stderr, "Output KEY (length %d)\n", tmpn);
 122             h__dump(tmpout, tmpn);
 123 #endif
 124             ret = 1;
 125             goto end;
 126         }
 127         n -= u;
 128         out += u;
 129         for (j = 0; j < v; j++)
 130             B[j] = Ai[j % u];
 131         /* Work out B + 1 first then can use B as tmp space */
 132         if (!BN_bin2bn(B, v, Bpl1))
 133             goto err;
 134         if (!BN_add_word(Bpl1, 1))
 135             goto err;
 136         for (j = 0; j < Ilen; j += v) {
 137             if (!BN_bin2bn(I + j, v, Ij))
 138                 goto err;
 139             if (!BN_add(Ij, Ij, Bpl1))
 140                 goto err;
 141             if (!BN_bn2bin(Ij, B))
 142                 goto err;
 143             Ijlen = BN_num_bytes(Ij);
 144             /* If more than 2^(v*8) - 1 cut off MSB */
 145             if (Ijlen > v) {
 146                 if (!BN_bn2bin(Ij, B))
 147                     goto err;
 148                 memcpy(I + j, B + 1, v);
 149 #ifndef PKCS12_BROKEN_KEYGEN
 150                 /* If less than v bytes pad with zeroes */
 151             } else if (Ijlen < v) {
 152                 memset(I + j, 0, v - Ijlen);
 153                 if (!BN_bn2bin(Ij, I + j + v - Ijlen))
 154                     goto err;
 155 #endif
 156             } else if (!BN_bn2bin(Ij, I + j))
 157                 goto err;
 158         }
 159     }
 160
 161  err:
 162     PKCS12err(PKCS12_F_PKCS12_KEY_GEN_UNI, ERR_R_MALLOC_FAILURE);
 163
 164  end:
 165     OPENSSL_free(Ai);
 166     OPENSSL_free(B);
 167     OPENSSL_free(D);
 168     OPENSSL_free(I);
 169     BN_free(Ij);
 170     BN_free(Bpl1);
 171     EVP_MD_CTX_free(ctx);
 172     return ret;
 173 }
 174
 175 #ifdef OPENSSL_DEBUG_KEYGEN
 176 void h__dump(unsigned char *p, int len)
 177 {
 178     for (; len--; p++)
 179         fprintf(stderr, "%02X", *p);
 180     fprintf(stderr, "\n");
 181 }
 182 #endif