/* 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/asn1.h> #include <string.h> #include <limits.h> #include <openssl_grpc/err.h> #include <openssl_grpc/mem.h> #include "../internal.h" ASN1_INTEGER *ASN1_INTEGER_dup(const ASN1_INTEGER *x) { return ASN1_STRING_dup(x); } int ASN1_INTEGER_cmp(const ASN1_INTEGER *x, const ASN1_INTEGER *y) { int neg, ret; /* Compare signs */ neg = x->type & V_ASN1_NEG; if (neg != (y->type & V_ASN1_NEG)) { if (neg) return -1; else return 1; } ret = ASN1_STRING_cmp(x, y); if (neg) return -ret; else return ret; } /* * This converts an ASN1 INTEGER into its content encoding. * The internal representation is an ASN1_STRING whose data is a big endian * representation of the value, ignoring the sign. The sign is determined by * the type: V_ASN1_INTEGER for positive and V_ASN1_NEG_INTEGER for negative. * * Positive integers are no problem: they are almost the same as the DER * encoding, except if the first byte is >= 0x80 we need to add a zero pad. * * Negative integers are a bit trickier... * The DER representation of negative integers is in 2s complement form. * The internal form is converted by complementing each octet and finally * adding one to the result. This can be done less messily with a little trick. * If the internal form has trailing zeroes then they will become FF by the * complement and 0 by the add one (due to carry) so just copy as many trailing * zeros to the destination as there are in the source. The carry will add one * to the last none zero octet: so complement this octet and add one and finally * complement any left over until you get to the start of the string. * * Padding is a little trickier too. If the first bytes is > 0x80 then we pad * with 0xff. However if the first byte is 0x80 and one of the following bytes * is non-zero we pad with 0xff. The reason for this distinction is that 0x80 * followed by optional zeros isn't padded. */ int i2c_ASN1_INTEGER(const ASN1_INTEGER *a, unsigned char **pp) { int pad = 0, ret, i, neg; unsigned char *p, *n, pb = 0; if (a == NULL) return (0); neg = a->type & V_ASN1_NEG; if (a->length == 0) ret = 1; else { ret = a->length; i = a->data[0]; if (ret == 1 && i == 0) neg = 0; if (!neg && (i > 127)) { pad = 1; pb = 0; } else if (neg) { if (i > 128) { pad = 1; pb = 0xFF; } else if (i == 128) { /* * Special case: if any other bytes non zero we pad: * otherwise we don't. */ for (i = 1; i < a->length; i++) if (a->data[i]) { pad = 1; pb = 0xFF; break; } } } ret += pad; } if (pp == NULL) return (ret); p = *pp; if (pad) *(p++) = pb; if (a->length == 0) *(p++) = 0; else if (!neg) OPENSSL_memcpy(p, a->data, (unsigned int)a->length); else { /* Begin at the end of the encoding */ n = a->data + a->length - 1; p += a->length - 1; i = a->length; /* Copy zeros to destination as long as source is zero */ while (!*n && i > 1) { *(p--) = 0; n--; i--; } /* Complement and increment next octet */ *(p--) = ((*(n--)) ^ 0xff) + 1; i--; /* Complement any octets left */ for (; i > 0; i--) *(p--) = *(n--) ^ 0xff; } *pp += ret; return (ret); } /* Convert just ASN1 INTEGER content octets to ASN1_INTEGER structure */ ASN1_INTEGER *c2i_ASN1_INTEGER(ASN1_INTEGER **a, const unsigned char **pp, long len) { ASN1_INTEGER *ret = NULL; const unsigned char *p, *pend; unsigned char *to, *s; int i; /* * This function can handle lengths up to INT_MAX - 1, but the rest of the * legacy ASN.1 code mixes integer types, so avoid exposing it to * ASN1_INTEGERS with larger lengths. */ if (len < 0 || len > INT_MAX / 2) { OPENSSL_PUT_ERROR(ASN1, ASN1_R_TOO_LONG); return NULL; } if ((a == NULL) || ((*a) == NULL)) { if ((ret = ASN1_INTEGER_new()) == NULL) return (NULL); ret->type = V_ASN1_INTEGER; } else ret = (*a); p = *pp; pend = p + len; /* * We must OPENSSL_malloc stuff, even for 0 bytes otherwise it signifies * a missing NULL parameter. */ s = (unsigned char *)OPENSSL_malloc((int)len + 1); if (s == NULL) { i = ERR_R_MALLOC_FAILURE; goto err; } to = s; if (!len) { /* * Strictly speaking this is an illegal INTEGER but we tolerate it. */ ret->type = V_ASN1_INTEGER; } else if (*p & 0x80) { /* a negative number */ ret->type = V_ASN1_NEG_INTEGER; if ((*p == 0xff) && (len != 1)) { p++; len--; } i = len; p += i - 1; to += i - 1; while ((!*p) && i) { *(to--) = 0; i--; p--; } /* * Special case: if all zeros then the number will be of the form FF * followed by n zero bytes: this corresponds to 1 followed by n zero * bytes. We've already written n zeros so we just append an extra * one and set the first byte to a 1. This is treated separately * because it is the only case where the number of bytes is larger * than len. */ if (!i) { *s = 1; s[len] = 0; len++; } else { *(to--) = (*(p--) ^ 0xff) + 1; i--; for (; i > 0; i--) *(to--) = *(p--) ^ 0xff; } } else { ret->type = V_ASN1_INTEGER; if ((*p == 0) && (len != 1)) { p++; len--; } OPENSSL_memcpy(s, p, (int)len); } if (ret->data != NULL) OPENSSL_free(ret->data); ret->data = s; ret->length = (int)len; if (a != NULL) (*a) = ret; *pp = pend; return (ret); err: OPENSSL_PUT_ERROR(ASN1, i); if ((ret != NULL) && ((a == NULL) || (*a != ret))) ASN1_INTEGER_free(ret); return (NULL); } int ASN1_INTEGER_set(ASN1_INTEGER *a, long v) { if (v >= 0) { return ASN1_INTEGER_set_uint64(a, (uint64_t) v); } if (!ASN1_INTEGER_set_uint64(a, 0 - (uint64_t) v)) { return 0; } a->type = V_ASN1_NEG_INTEGER; return 1; } int ASN1_INTEGER_set_uint64(ASN1_INTEGER *out, uint64_t v) { uint8_t *const newdata = OPENSSL_malloc(sizeof(uint64_t)); if (newdata == NULL) { OPENSSL_PUT_ERROR(ASN1, ERR_R_MALLOC_FAILURE); return 0; } OPENSSL_free(out->data); out->data = newdata; v = CRYPTO_bswap8(v); memcpy(out->data, &v, sizeof(v)); out->type = V_ASN1_INTEGER; size_t leading_zeros; for (leading_zeros = 0; leading_zeros < sizeof(uint64_t) - 1; leading_zeros++) { if (out->data[leading_zeros] != 0) { break; } } out->length = sizeof(uint64_t) - leading_zeros; OPENSSL_memmove(out->data, out->data + leading_zeros, out->length); return 1; } long ASN1_INTEGER_get(const ASN1_INTEGER *a) { int neg = 0, i; if (a == NULL) return (0L); i = a->type; if (i == V_ASN1_NEG_INTEGER) neg = 1; else if (i != V_ASN1_INTEGER) return -1; OPENSSL_STATIC_ASSERT(sizeof(uint64_t) >= sizeof(long), "long larger than uint64_t"); if (a->length > (int)sizeof(uint64_t)) { /* hmm... a bit ugly, return all ones */ return -1; } uint64_t r64 = 0; if (a->data != NULL) { for (i = 0; i < a->length; i++) { r64 <<= 8; r64 |= (unsigned char)a->data[i]; } if (r64 > LONG_MAX) { return -1; } } long r = (long) r64; if (neg) r = -r; return r; } ASN1_INTEGER *BN_to_ASN1_INTEGER(const BIGNUM *bn, ASN1_INTEGER *ai) { ASN1_INTEGER *ret; int len, j; if (ai == NULL) ret = ASN1_INTEGER_new(); else ret = ai; if (ret == NULL) { OPENSSL_PUT_ERROR(ASN1, ASN1_R_NESTED_ASN1_ERROR); goto err; } if (BN_is_negative(bn) && !BN_is_zero(bn)) ret->type = V_ASN1_NEG_INTEGER; else ret->type = V_ASN1_INTEGER; j = BN_num_bits(bn); len = ((j == 0) ? 0 : ((j / 8) + 1)); if (ret->length < len + 4) { unsigned char *new_data = OPENSSL_realloc(ret->data, len + 4); if (!new_data) { OPENSSL_PUT_ERROR(ASN1, ERR_R_MALLOC_FAILURE); goto err; } ret->data = new_data; } ret->length = BN_bn2bin(bn, ret->data); /* Correct zero case */ if (!ret->length) { ret->data[0] = 0; ret->length = 1; } return (ret); err: if (ret != ai) ASN1_INTEGER_free(ret); return (NULL); } BIGNUM *ASN1_INTEGER_to_BN(const ASN1_INTEGER *ai, BIGNUM *bn) { BIGNUM *ret; if ((ret = BN_bin2bn(ai->data, ai->length, bn)) == NULL) OPENSSL_PUT_ERROR(ASN1, ASN1_R_BN_LIB); else if (ai->type == V_ASN1_NEG_INTEGER) BN_set_negative(ret, 1); return (ret); }