/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) * All rights reserved. * * This package is an SSL implementation written * by Eric Young (eay@cryptsoft.com). * The implementation was written so as to conform with Netscapes SSL. * * This library is free for commercial and non-commercial use as long as * the following conditions are aheared to. The following conditions * apply to all code found in this distribution, be it the RC4, RSA, * lhash, DES, etc., code; not just the SSL code. The SSL documentation * included with this distribution is covered by the same copyright terms * except that the holder is Tim Hudson (tjh@cryptsoft.com). * * Copyright remains Eric Young's, and as such any Copyright notices in * the code are not to be removed. * If this package is used in a product, Eric Young should be given attribution * as the author of the parts of the library used. * This can be in the form of a textual message at program startup or * in documentation (online or textual) provided with the package. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * "This product includes cryptographic software written by * Eric Young (eay@cryptsoft.com)" * The word 'cryptographic' can be left out if the rouines from the library * being used are not cryptographic related :-). * 4. If you include any Windows specific code (or a derivative thereof) from * the apps directory (application code) you must include an acknowledgement: * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" * * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * The licence and distribution terms for any publically available version or * derivative of this code cannot be changed. i.e. this code cannot simply be * copied and put under another distribution licence * [including the GNU Public Licence.] */ #include <openssl_grpc/bn.h> #include <assert.h> #include <ctype.h> #include <limits.h> #include <stdio.h> #include <openssl_grpc/bio.h> #include <openssl_grpc/bytestring.h> #include <openssl_grpc/err.h> #include <openssl_grpc/mem.h> #include "../fipsmodule/bn/internal.h" int BN_bn2cbb_padded(CBB *out, size_t len, const BIGNUM *in) { uint8_t *ptr; return CBB_add_space(out, &ptr, len) && BN_bn2bin_padded(ptr, len, in); } static const char hextable[] = "0123456789abcdef"; char *BN_bn2hex(const BIGNUM *bn) { int width = bn_minimal_width(bn); char *buf = OPENSSL_malloc(1 /* leading '-' */ + 1 /* zero is non-empty */ + width * BN_BYTES * 2 + 1 /* trailing NUL */); if (buf == NULL) { OPENSSL_PUT_ERROR(BN, ERR_R_MALLOC_FAILURE); return NULL; } char *p = buf; if (bn->neg) { *(p++) = '-'; } if (BN_is_zero(bn)) { *(p++) = '0'; } int z = 0; for (int i = width - 1; i >= 0; i--) { for (int j = BN_BITS2 - 8; j >= 0; j -= 8) { // strip leading zeros int v = ((int)(bn->d[i] >> (long)j)) & 0xff; if (z || v != 0) { *(p++) = hextable[v >> 4]; *(p++) = hextable[v & 0x0f]; z = 1; } } } *p = '\0'; return buf; } // decode_hex decodes |in_len| bytes of hex data from |in| and updates |bn|. static int decode_hex(BIGNUM *bn, const char *in, int in_len) { if (in_len > INT_MAX/4) { OPENSSL_PUT_ERROR(BN, BN_R_BIGNUM_TOO_LONG); return 0; } // |in_len| is the number of hex digits. if (!bn_expand(bn, in_len * 4)) { return 0; } int i = 0; while (in_len > 0) { // Decode one |BN_ULONG| at a time. int todo = BN_BYTES * 2; if (todo > in_len) { todo = in_len; } BN_ULONG word = 0; int j; for (j = todo; j > 0; j--) { char c = in[in_len - j]; BN_ULONG hex; if (c >= '0' && c <= '9') { hex = c - '0'; } else if (c >= 'a' && c <= 'f') { hex = c - 'a' + 10; } else if (c >= 'A' && c <= 'F') { hex = c - 'A' + 10; } else { hex = 0; // This shouldn't happen. The caller checks |isxdigit|. assert(0); } word = (word << 4) | hex; } bn->d[i++] = word; in_len -= todo; } assert(i <= bn->dmax); bn->width = i; return 1; } // decode_dec decodes |in_len| bytes of decimal data from |in| and updates |bn|. static int decode_dec(BIGNUM *bn, const char *in, int in_len) { int i, j; BN_ULONG l = 0; // Decode |BN_DEC_NUM| digits at a time. j = BN_DEC_NUM - (in_len % BN_DEC_NUM); if (j == BN_DEC_NUM) { j = 0; } l = 0; for (i = 0; i < in_len; i++) { l *= 10; l += in[i] - '0'; if (++j == BN_DEC_NUM) { if (!BN_mul_word(bn, BN_DEC_CONV) || !BN_add_word(bn, l)) { return 0; } l = 0; j = 0; } } return 1; } typedef int (*decode_func) (BIGNUM *bn, const char *in, int in_len); typedef int (*char_test_func) (int c); static int bn_x2bn(BIGNUM **outp, const char *in, decode_func decode, char_test_func want_char) { BIGNUM *ret = NULL; int neg = 0, i; int num; if (in == NULL || *in == 0) { return 0; } if (*in == '-') { neg = 1; in++; } for (i = 0; want_char((unsigned char)in[i]) && i + neg < INT_MAX; i++) {} num = i + neg; if (outp == NULL) { return num; } // in is the start of the hex digits, and it is 'i' long if (*outp == NULL) { ret = BN_new(); if (ret == NULL) { return 0; } } else { ret = *outp; BN_zero(ret); } if (!decode(ret, in, i)) { goto err; } bn_set_minimal_width(ret); if (!BN_is_zero(ret)) { ret->neg = neg; } *outp = ret; return num; err: if (*outp == NULL) { BN_free(ret); } return 0; } int BN_hex2bn(BIGNUM **outp, const char *in) { return bn_x2bn(outp, in, decode_hex, isxdigit); } char *BN_bn2dec(const BIGNUM *a) { // It is easier to print strings little-endian, so we assemble it in reverse // and fix at the end. BIGNUM *copy = NULL; CBB cbb; if (!CBB_init(&cbb, 16) || !CBB_add_u8(&cbb, 0 /* trailing NUL */)) { goto cbb_err; } if (BN_is_zero(a)) { if (!CBB_add_u8(&cbb, '0')) { goto cbb_err; } } else { copy = BN_dup(a); if (copy == NULL) { goto err; } while (!BN_is_zero(copy)) { BN_ULONG word = BN_div_word(copy, BN_DEC_CONV); if (word == (BN_ULONG)-1) { goto err; } const int add_leading_zeros = !BN_is_zero(copy); for (int i = 0; i < BN_DEC_NUM && (add_leading_zeros || word != 0); i++) { if (!CBB_add_u8(&cbb, '0' + word % 10)) { goto cbb_err; } word /= 10; } assert(word == 0); } } if (BN_is_negative(a) && !CBB_add_u8(&cbb, '-')) { goto cbb_err; } uint8_t *data; size_t len; if (!CBB_finish(&cbb, &data, &len)) { goto cbb_err; } // Reverse the buffer. for (size_t i = 0; i < len/2; i++) { uint8_t tmp = data[i]; data[i] = data[len - 1 - i]; data[len - 1 - i] = tmp; } BN_free(copy); return (char *)data; cbb_err: OPENSSL_PUT_ERROR(BN, ERR_R_MALLOC_FAILURE); err: BN_free(copy); CBB_cleanup(&cbb); return NULL; } int BN_dec2bn(BIGNUM **outp, const char *in) { return bn_x2bn(outp, in, decode_dec, isdigit); } int BN_asc2bn(BIGNUM **outp, const char *in) { const char *const orig_in = in; if (*in == '-') { in++; } if (in[0] == '0' && (in[1] == 'X' || in[1] == 'x')) { if (!BN_hex2bn(outp, in+2)) { return 0; } } else { if (!BN_dec2bn(outp, in)) { return 0; } } if (*orig_in == '-' && !BN_is_zero(*outp)) { (*outp)->neg = 1; } return 1; } int BN_print(BIO *bp, const BIGNUM *a) { int i, j, v, z = 0; int ret = 0; if (a->neg && BIO_write(bp, "-", 1) != 1) { goto end; } if (BN_is_zero(a) && BIO_write(bp, "0", 1) != 1) { goto end; } for (i = bn_minimal_width(a) - 1; i >= 0; i--) { for (j = BN_BITS2 - 4; j >= 0; j -= 4) { // strip leading zeros v = ((int)(a->d[i] >> (long)j)) & 0x0f; if (z || v != 0) { if (BIO_write(bp, &hextable[v], 1) != 1) { goto end; } z = 1; } } } ret = 1; end: return ret; } int BN_print_fp(FILE *fp, const BIGNUM *a) { BIO *b = BIO_new_fp(fp, BIO_NOCLOSE); if (b == NULL) { return 0; } int ret = BN_print(b, a); BIO_free(b); return ret; } size_t BN_bn2mpi(const BIGNUM *in, uint8_t *out) { const size_t bits = BN_num_bits(in); const size_t bytes = (bits + 7) / 8; // If the number of bits is a multiple of 8, i.e. if the MSB is set, // prefix with a zero byte. int extend = 0; if (bytes != 0 && (bits & 0x07) == 0) { extend = 1; } const size_t len = bytes + extend; if (len < bytes || 4 + len < len || (len & 0xffffffff) != len) { // If we cannot represent the number then we emit zero as the interface // doesn't allow an error to be signalled. if (out) { OPENSSL_memset(out, 0, 4); } return 4; } if (out == NULL) { return 4 + len; } out[0] = len >> 24; out[1] = len >> 16; out[2] = len >> 8; out[3] = len; if (extend) { out[4] = 0; } BN_bn2bin(in, out + 4 + extend); if (in->neg && len > 0) { out[4] |= 0x80; } return len + 4; } BIGNUM *BN_mpi2bn(const uint8_t *in, size_t len, BIGNUM *out) { if (len < 4) { OPENSSL_PUT_ERROR(BN, BN_R_BAD_ENCODING); return NULL; } const size_t in_len = ((size_t)in[0] << 24) | ((size_t)in[1] << 16) | ((size_t)in[2] << 8) | ((size_t)in[3]); if (in_len != len - 4) { OPENSSL_PUT_ERROR(BN, BN_R_BAD_ENCODING); return NULL; } int out_is_alloced = 0; if (out == NULL) { out = BN_new(); if (out == NULL) { OPENSSL_PUT_ERROR(BN, ERR_R_MALLOC_FAILURE); return NULL; } out_is_alloced = 1; } if (in_len == 0) { BN_zero(out); return out; } in += 4; if (BN_bin2bn(in, in_len, out) == NULL) { if (out_is_alloced) { BN_free(out); } return NULL; } out->neg = ((*in) & 0x80) != 0; if (out->neg) { BN_clear_bit(out, BN_num_bits(out) - 1); } return out; } int BN_bn2binpad(const BIGNUM *in, uint8_t *out, int len) { if (len < 0 || !BN_bn2bin_padded(out, (size_t)len, in)) { return -1; } return len; }