From aa4d426b4d3527d7e166df1a05058c9a4a0f6683 Mon Sep 17 00:00:00 2001 From: Wojtek Kosior Date: Fri, 30 Apr 2021 00:33:56 +0200 Subject: initial/final commit --- openssl-1.1.0h/crypto/bn/README.pod | 247 ++++++++++++++++++++++++++++++++++++ 1 file changed, 247 insertions(+) create mode 100644 openssl-1.1.0h/crypto/bn/README.pod (limited to 'openssl-1.1.0h/crypto/bn/README.pod') diff --git a/openssl-1.1.0h/crypto/bn/README.pod b/openssl-1.1.0h/crypto/bn/README.pod new file mode 100644 index 0000000..109ab0d --- /dev/null +++ b/openssl-1.1.0h/crypto/bn/README.pod @@ -0,0 +1,247 @@ +=pod + +=head1 NAME + +bn_mul_words, bn_mul_add_words, bn_sqr_words, bn_div_words, +bn_add_words, bn_sub_words, bn_mul_comba4, bn_mul_comba8, +bn_sqr_comba4, bn_sqr_comba8, bn_cmp_words, bn_mul_normal, +bn_mul_low_normal, bn_mul_recursive, bn_mul_part_recursive, +bn_mul_low_recursive, bn_mul_high, bn_sqr_normal, bn_sqr_recursive, +bn_expand, bn_wexpand, bn_expand2, bn_fix_top, bn_check_top, +bn_print, bn_dump, bn_set_max, bn_set_high, bn_set_low - BIGNUM +library internal functions + +=head1 SYNOPSIS + + #include + + BN_ULONG bn_mul_words(BN_ULONG *rp, BN_ULONG *ap, int num, BN_ULONG w); + BN_ULONG bn_mul_add_words(BN_ULONG *rp, BN_ULONG *ap, int num, + BN_ULONG w); + void bn_sqr_words(BN_ULONG *rp, BN_ULONG *ap, int num); + BN_ULONG bn_div_words(BN_ULONG h, BN_ULONG l, BN_ULONG d); + BN_ULONG bn_add_words(BN_ULONG *rp, BN_ULONG *ap, BN_ULONG *bp, + int num); + BN_ULONG bn_sub_words(BN_ULONG *rp, BN_ULONG *ap, BN_ULONG *bp, + int num); + + void bn_mul_comba4(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b); + void bn_mul_comba8(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b); + void bn_sqr_comba4(BN_ULONG *r, BN_ULONG *a); + void bn_sqr_comba8(BN_ULONG *r, BN_ULONG *a); + + int bn_cmp_words(BN_ULONG *a, BN_ULONG *b, int n); + + void bn_mul_normal(BN_ULONG *r, BN_ULONG *a, int na, BN_ULONG *b, + int nb); + void bn_mul_low_normal(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n); + void bn_mul_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n2, + int dna, int dnb, BN_ULONG *tmp); + void bn_mul_part_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, + int n, int tna, int tnb, BN_ULONG *tmp); + void bn_mul_low_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, + int n2, BN_ULONG *tmp); + void bn_mul_high(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, BN_ULONG *l, + int n2, BN_ULONG *tmp); + + void bn_sqr_normal(BN_ULONG *r, BN_ULONG *a, int n, BN_ULONG *tmp); + void bn_sqr_recursive(BN_ULONG *r, BN_ULONG *a, int n2, BN_ULONG *tmp); + + void mul(BN_ULONG r, BN_ULONG a, BN_ULONG w, BN_ULONG c); + void mul_add(BN_ULONG r, BN_ULONG a, BN_ULONG w, BN_ULONG c); + void sqr(BN_ULONG r0, BN_ULONG r1, BN_ULONG a); + + BIGNUM *bn_expand(BIGNUM *a, int bits); + BIGNUM *bn_wexpand(BIGNUM *a, int n); + BIGNUM *bn_expand2(BIGNUM *a, int n); + void bn_fix_top(BIGNUM *a); + + void bn_check_top(BIGNUM *a); + void bn_print(BIGNUM *a); + void bn_dump(BN_ULONG *d, int n); + void bn_set_max(BIGNUM *a); + void bn_set_high(BIGNUM *r, BIGNUM *a, int n); + void bn_set_low(BIGNUM *r, BIGNUM *a, int n); + +=head1 DESCRIPTION + +This page documents the internal functions used by the OpenSSL +B implementation. They are described here to facilitate +debugging and extending the library. They are I to be used by +applications. + +=head2 The BIGNUM structure + + typedef struct bignum_st BIGNUM; + + struct bignum_st + { + BN_ULONG *d; /* Pointer to an array of 'BN_BITS2' bit chunks. */ + int top; /* Index of last used d +1. */ + /* The next are internal book keeping for bn_expand. */ + int dmax; /* Size of the d array. */ + int neg; /* one if the number is negative */ + int flags; + }; + + +The integer value is stored in B, a malloc()ed array of words (B), +least significant word first. A B can be either 16, 32 or 64 bits +in size, depending on the 'number of bits' (B) specified in +C. + +B is the size of the B array that has been allocated. B +is the number of words being used, so for a value of 4, bn.d[0]=4 and +bn.top=1. B is 1 if the number is negative. When a B is +B<0>, the B field can be B and B == B<0>. + +B is a bit field of flags which are defined in C. The +flags begin with B. The macros BN_set_flags(b, n) and +BN_get_flags(b, n) exist to enable or fetch flag(s) B from B +structure B. + +Various routines in this library require the use of temporary +B variables during their execution. Since dynamic memory +allocation to create Bs is rather expensive when used in +conjunction with repeated subroutine calls, the B structure is +used. This structure contains B Bs, see +L. + +=head2 Low-level arithmetic operations + +These functions are implemented in C and for several platforms in +assembly language: + +bn_mul_words(B, B, B, B) operates on the B word +arrays B and B. It computes B * B, places the result +in B, and returns the high word (carry). + +bn_mul_add_words(B, B, B, B) operates on the B +word arrays B and B. It computes B * B + B, places +the result in B, and returns the high word (carry). + +bn_sqr_words(B, B, B) operates on the B word array +B and the 2*B word array B. It computes B * B +word-wise, and places the low and high bytes of the result in B. + +bn_div_words(B, B, B) divides the two word number (B, B) +by B and returns the result. + +bn_add_words(B, B, B, B) operates on the B word +arrays B, B and B. It computes B + B, places the +result in B, and returns the high word (carry). + +bn_sub_words(B, B, B, B) operates on the B word +arrays B, B and B. It computes B - B, places the +result in B, and returns the carry (1 if B E B, 0 +otherwise). + +bn_mul_comba4(B, B, B) operates on the 4 word arrays B and +B and the 8 word array B. It computes B*B and places the +result in B. + +bn_mul_comba8(B, B, B) operates on the 8 word arrays B and +B and the 16 word array B. It computes B*B and places the +result in B. + +bn_sqr_comba4(B, B, B) operates on the 4 word arrays B and +B and the 8 word array B. + +bn_sqr_comba8(B, B, B) operates on the 8 word arrays B and +B and the 16 word array B. + +The following functions are implemented in C: + +bn_cmp_words(B, B, B) operates on the B word arrays B +and B. It returns 1, 0 and -1 if B is greater than, equal and +less than B. + +bn_mul_normal(B, B, B, B, B) operates on the B +word array B, the B word array B and the B+B word +array B. It computes B*B and places the result in B. + +bn_mul_low_normal(B, B, B, B) operates on the B word +arrays B, B and B. It computes the B low words of +B*B and places the result in B. + +bn_mul_recursive(B, B, B, B, B, B, B) operates +on the word arrays B and B of length B+B and B+B +(B and B are currently allowed to be 0 or negative) and the 2*B +word arrays B and B. B must be a power of 2. It computes +B*B and places the result in B. + +bn_mul_part_recursive(B, B, B, B, B, B, B) +operates on the word arrays B and B of length B+B and +B+B and the 4*B word arrays B and B. + +bn_mul_low_recursive(B, B, B, B, B) operates on the +B word arrays B and B and the B/2 word arrays B +and B. + +bn_mul_high(B, B, B, B, B, B) operates on the +B word arrays B, B, B and B (?) and the 3*B word +array B. + +BN_mul() calls bn_mul_normal(), or an optimized implementation if the +factors have the same size: bn_mul_comba8() is used if they are 8 +words long, bn_mul_recursive() if they are larger than +B and the size is an exact multiple of the word +size, and bn_mul_part_recursive() for others that are larger than +B. + +bn_sqr_normal(B, B, B, B) operates on the B word array +B and the 2*B word arrays B and B. + +The implementations use the following macros which, depending on the +architecture, may use "long long" C operations or inline assembler. +They are defined in C. + +mul(B, B, B, B) computes B*B+B and places the +low word of the result in B and the high word in B. + +mul_add(B, B, B, B) computes B*B+B+B and +places the low word of the result in B and the high word in B. + +sqr(B, B, B) computes B*B and places the low word +of the result in B and the high word in B. + +=head2 Size changes + +bn_expand() ensures that B has enough space for a B bit +number. bn_wexpand() ensures that B has enough space for an +B word number. If the number has to be expanded, both macros +call bn_expand2(), which allocates a new B array and copies the +data. They return B on error, B otherwise. + +The bn_fix_top() macro reduces Btop> to point to the most +significant non-zero word plus one when B has shrunk. + +=head2 Debugging + +bn_check_top() verifies that C<((a)-Etop E= 0 && (a)-Etop +E= (a)-Edmax)>. A violation will cause the program to abort. + +bn_print() prints B to stderr. bn_dump() prints B words at B +(in reverse order, i.e. most significant word first) to stderr. + +bn_set_max() makes B a static number with a B of its current size. +This is used by bn_set_low() and bn_set_high() to make B a read-only +B that contains the B low or high words of B. + +If B is not defined, bn_check_top(), bn_print(), bn_dump() +and bn_set_max() are defined as empty macros. + +=head1 SEE ALSO + +L + +=head1 COPYRIGHT + +Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved. + +Licensed under the OpenSSL license (the "License"). You may not use +this file except in compliance with the License. You can obtain a copy +in the file LICENSE in the source distribution or at +L. + +=cut -- cgit v1.2.3