x_bignum.c 5.4 KB

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  1. /* x_bignum.c */
  2. /*
  3. * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL project
  4. * 2000.
  5. */
  6. /* ====================================================================
  7. * Copyright (c) 2000 The OpenSSL Project. All rights reserved.
  8. *
  9. * Redistribution and use in source and binary forms, with or without
  10. * modification, are permitted provided that the following conditions
  11. * are met:
  12. *
  13. * 1. Redistributions of source code must retain the above copyright
  14. * notice, this list of conditions and the following disclaimer.
  15. *
  16. * 2. Redistributions in binary form must reproduce the above copyright
  17. * notice, this list of conditions and the following disclaimer in
  18. * the documentation and/or other materials provided with the
  19. * distribution.
  20. *
  21. * 3. All advertising materials mentioning features or use of this
  22. * software must display the following acknowledgment:
  23. * "This product includes software developed by the OpenSSL Project
  24. * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
  25. *
  26. * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  27. * endorse or promote products derived from this software without
  28. * prior written permission. For written permission, please contact
  29. * licensing@OpenSSL.org.
  30. *
  31. * 5. Products derived from this software may not be called "OpenSSL"
  32. * nor may "OpenSSL" appear in their names without prior written
  33. * permission of the OpenSSL Project.
  34. *
  35. * 6. Redistributions of any form whatsoever must retain the following
  36. * acknowledgment:
  37. * "This product includes software developed by the OpenSSL Project
  38. * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
  39. *
  40. * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  41. * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  42. * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  43. * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
  44. * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  45. * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  46. * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  47. * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  48. * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  49. * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  50. * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  51. * OF THE POSSIBILITY OF SUCH DAMAGE.
  52. * ====================================================================
  53. *
  54. * This product includes cryptographic software written by Eric Young
  55. * (eay@cryptsoft.com). This product includes software written by Tim
  56. * Hudson (tjh@cryptsoft.com).
  57. *
  58. */
  59. #include <stdio.h>
  60. #include "cryptlib.h"
  61. #include <openssl/asn1t.h>
  62. #include <openssl/bn.h>
  63. /*
  64. * Custom primitive type for BIGNUM handling. This reads in an ASN1_INTEGER
  65. * as a BIGNUM directly. Currently it ignores the sign which isn't a problem
  66. * since all BIGNUMs used are non negative and anything that looks negative
  67. * is normally due to an encoding error.
  68. */
  69. #define BN_SENSITIVE 1
  70. static int bn_new(ASN1_VALUE **pval, const ASN1_ITEM *it);
  71. static void bn_free(ASN1_VALUE **pval, const ASN1_ITEM *it);
  72. static int bn_i2c(ASN1_VALUE **pval, unsigned char *cont, int *putype,
  73. const ASN1_ITEM *it);
  74. static int bn_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len,
  75. int utype, char *free_cont, const ASN1_ITEM *it);
  76. static int bn_print(BIO *out, ASN1_VALUE **pval, const ASN1_ITEM *it,
  77. int indent, const ASN1_PCTX *pctx);
  78. static ASN1_PRIMITIVE_FUNCS bignum_pf = {
  79. NULL, 0,
  80. bn_new,
  81. bn_free,
  82. 0,
  83. bn_c2i,
  84. bn_i2c,
  85. bn_print
  86. };
  87. ASN1_ITEM_start(BIGNUM)
  88. ASN1_ITYPE_PRIMITIVE, V_ASN1_INTEGER, NULL, 0, &bignum_pf, 0, "BIGNUM"
  89. ASN1_ITEM_end(BIGNUM)
  90. ASN1_ITEM_start(CBIGNUM)
  91. ASN1_ITYPE_PRIMITIVE, V_ASN1_INTEGER, NULL, 0, &bignum_pf, BN_SENSITIVE, "BIGNUM"
  92. ASN1_ITEM_end(CBIGNUM)
  93. static int bn_new(ASN1_VALUE **pval, const ASN1_ITEM *it)
  94. {
  95. *pval = (ASN1_VALUE *)BN_new();
  96. if (*pval)
  97. return 1;
  98. else
  99. return 0;
  100. }
  101. static void bn_free(ASN1_VALUE **pval, const ASN1_ITEM *it)
  102. {
  103. if (!*pval)
  104. return;
  105. if (it->size & BN_SENSITIVE)
  106. BN_clear_free((BIGNUM *)*pval);
  107. else
  108. BN_free((BIGNUM *)*pval);
  109. *pval = NULL;
  110. }
  111. static int bn_i2c(ASN1_VALUE **pval, unsigned char *cont, int *putype,
  112. const ASN1_ITEM *it)
  113. {
  114. BIGNUM *bn;
  115. int pad;
  116. if (!*pval)
  117. return -1;
  118. bn = (BIGNUM *)*pval;
  119. /* If MSB set in an octet we need a padding byte */
  120. if (BN_num_bits(bn) & 0x7)
  121. pad = 0;
  122. else
  123. pad = 1;
  124. if (cont) {
  125. if (pad)
  126. *cont++ = 0;
  127. BN_bn2bin(bn, cont);
  128. }
  129. return pad + BN_num_bytes(bn);
  130. }
  131. static int bn_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len,
  132. int utype, char *free_cont, const ASN1_ITEM *it)
  133. {
  134. BIGNUM *bn;
  135. if (*pval == NULL && !bn_new(pval, it))
  136. return 0;
  137. bn = (BIGNUM *)*pval;
  138. if (!BN_bin2bn(cont, len, bn)) {
  139. bn_free(pval, it);
  140. return 0;
  141. }
  142. return 1;
  143. }
  144. static int bn_print(BIO *out, ASN1_VALUE **pval, const ASN1_ITEM *it,
  145. int indent, const ASN1_PCTX *pctx)
  146. {
  147. if (!BN_print(out, *(BIGNUM **)pval))
  148. return 0;
  149. if (BIO_puts(out, "\n") <= 0)
  150. return 0;
  151. return 1;
  152. }