From 55bbd84445c0c63a49cc8832f0c4190edaac12b9 Mon Sep 17 00:00:00 2001 From: Daniel Pouzzner Date: Wed, 14 May 2025 15:38:12 -0500 Subject: [PATCH] wolfssl/wolfcrypt/sp_int.h and wolfcrypt/src/sp_int.c: add WOLFSSL_SP_DYN_STACK macro to orthogonalize gnarly setup logic, and refactor to use it throughout; refactor several more sp_int stack-allocated data buffers as sp_int_digit[]s rather than char[]s. --- wolfcrypt/src/sp_int.c | 44 ++++++++++++-------------------------- wolfssl/wolfcrypt/sp_int.h | 36 ++++++++++++++++++++----------- 2 files changed, 37 insertions(+), 43 deletions(-) diff --git a/wolfcrypt/src/sp_int.c b/wolfcrypt/src/sp_int.c index e3a003cf1..35bc0bfee 100644 --- a/wolfcrypt/src/sp_int.c +++ b/wolfcrypt/src/sp_int.c @@ -31,17 +31,13 @@ This library provides single precision (SP) integer math functions. #if defined(WOLFSSL_SP_MATH) || defined(WOLFSSL_SP_MATH_ALL) -#if (!defined(WOLFSSL_SMALL_STACK) && !defined(SP_ALLOC)) || \ - defined(WOLFSSL_SP_NO_MALLOC) -#if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) && \ - !defined(WOLFSSL_SP_NO_DYN_STACK) -PRAGMA_GCC_DIAG_PUSH +#ifdef WOLFSSL_SP_DYN_STACK /* We are statically declaring a variable smaller than sp_int. * We track available memory in the 'size' field. * Disable warnings of sp_int being partly outside array bounds of variable. */ -PRAGMA_GCC("GCC diagnostic ignored \"-Warray-bounds\"") -#endif + PRAGMA_GCC_DIAG_PUSH + PRAGMA_GCC("GCC diagnostic ignored \"-Warray-bounds\"") #endif #ifdef NO_INLINE @@ -98,7 +94,7 @@ PRAGMA_GCC("GCC diagnostic ignored \"-Warray-bounds\"") * WOLFSSL_SP_INT_NEGATIVE Enables negative values to be used. * WOLFSSL_SP_INT_DIGIT_ALIGN Enable when unaligned access of sp_int_digit * pointer is not allowed. - * WOLFSSL_SP_NO_DYN_STACK Disable use of dynamic stack items. + * WOLFSSL_SP_DYN_STACK Enable use of dynamic stack items. * Dynamic arrays used when not small stack. * WOLFSSL_SP_FAST_MODEXP Allow fast mod_exp with small C code * WOLFSSL_SP_LOW_MEM Use algorithms that use less memory. @@ -127,8 +123,7 @@ PRAGMA_GCC("GCC diagnostic ignored \"-Warray-bounds\"") #define DECL_SP_INT(n, s) \ sp_int* n = NULL #else - #if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) && \ - !defined(WOLFSSL_SP_NO_DYN_STACK) + #ifdef WOLFSSL_SP_DYN_STACK /* Declare a variable on the stack with the required data size. */ #define DECL_SP_INT(n, s) \ sp_int_digit n##d[MP_INT_SIZEOF_DIGITS(s)]; \ @@ -218,8 +213,7 @@ PRAGMA_GCC("GCC diagnostic ignored \"-Warray-bounds\"") /* Declare a variable that will be assigned a value on XMALLOC. */ #define DECL_SP_INT_ARRAY(n, s, c) \ DECL_DYN_SP_INT_ARRAY(n, s, c) -#elif defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) && \ - !defined(WOLFSSL_SP_NO_DYN_STACK) +#elif defined(WOLFSSL_SP_DYN_STACK) /* Declare a variable on the stack with the required data size. */ #define DECL_SP_INT_ARRAY(n, s, c) \ sp_int_digit n##d[MP_INT_SIZEOF_DIGITS(s) * (c)]; \ @@ -264,8 +258,7 @@ while (0) !defined(WOLFSSL_SP_NO_MALLOC) #define ALLOC_SP_INT_ARRAY(n, s, c, err, h) \ ALLOC_DYN_SP_INT_ARRAY(n, s, c, err, h) -#elif defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) && \ - !defined(WOLFSSL_SP_NO_DYN_STACK) +#elif defined(WOLFSSL_SP_DYN_STACK) /* Data declared on stack that supports multiple sp_ints of the * required size. Use pointers into data to make up array and set sizes. */ @@ -9175,8 +9168,7 @@ static int _sp_mul_nxn(const sp_int* a, const sp_int* b, sp_int* r) unsigned int k; #if defined(WOLFSSL_SMALL_STACK) && !defined(WOLFSSL_SP_NO_MALLOC) sp_int_digit* t = NULL; -#elif defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) && \ - !defined(WOLFSSL_SP_NO_DYN_STACK) +#elif defined(WOLFSSL_SP_DYN_STACK) sp_int_digit t[a->used]; #else sp_int_digit t[SP_INT_DIGITS / 2]; @@ -9252,8 +9244,7 @@ static int _sp_mul(const sp_int* a, const sp_int* b, sp_int* r) sp_size_t k; #if defined(WOLFSSL_SMALL_STACK) && !defined(WOLFSSL_SP_NO_MALLOC) sp_int_digit* t = NULL; -#elif defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) && \ - !defined(WOLFSSL_SP_NO_DYN_STACK) +#elif defined(WOLFSSL_SP_DYN_STACK) sp_int_digit t[a->used + b->used]; #else sp_int_digit t[SP_INT_DIGITS]; @@ -9329,8 +9320,7 @@ static int _sp_mul(const sp_int* a, const sp_int* b, sp_int* r) sp_size_t k; #if defined(WOLFSSL_SMALL_STACK) && !defined(WOLFSSL_SP_NO_MALLOC) sp_int_digit* t = NULL; -#elif defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) && \ - !defined(WOLFSSL_SP_NO_DYN_STACK) +#elif defined(WOLFSSL_SP_DYN_STACK) sp_int_digit t[a->used + b->used]; #else sp_int_digit t[SP_INT_DIGITS]; @@ -14879,8 +14869,7 @@ static int _sp_sqr(const sp_int* a, sp_int* r) sp_size_t k; #if defined(WOLFSSL_SMALL_STACK) && !defined(WOLFSSL_SP_NO_MALLOC) sp_int_digit* t = NULL; -#elif defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) && \ - !defined(WOLFSSL_SP_NO_DYN_STACK) +#elif defined(WOLFSSL_SP_DYN_STACK) sp_int_digit t[((a->used + 1) / 2) * 2 + 1]; #else sp_int_digit t[(SP_INT_DIGITS + 1) / 2]; @@ -14994,8 +14983,7 @@ static int _sp_sqr(const sp_int* a, sp_int* r) sp_size_t k; #if defined(WOLFSSL_SMALL_STACK) && !defined(WOLFSSL_SP_NO_MALLOC) sp_int_digit* t = NULL; -#elif defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) && \ - !defined(WOLFSSL_SP_NO_DYN_STACK) +#elif defined(WOLFSSL_SP_DYN_STACK) sp_int_digit t[a->used * 2]; #else sp_int_digit t[SP_INT_DIGITS]; @@ -19891,12 +19879,8 @@ void sp_memzero_check(sp_int* sp) } #endif /* WOLFSSL_CHECK_MEM_ZERO */ -#if (!defined(WOLFSSL_SMALL_STACK) && !defined(SP_ALLOC)) || \ - defined(WOLFSSL_SP_NO_MALLOC) -#if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) && \ - !defined(WOLFSSL_SP_NO_DYN_STACK) -PRAGMA_GCC_DIAG_POP -#endif +#ifdef WOLFSSL_SP_DYN_STACK + PRAGMA_GCC_DIAG_POP #endif #endif /* WOLFSSL_SP_MATH || WOLFSSL_SP_MATH_ALL */ diff --git a/wolfssl/wolfcrypt/sp_int.h b/wolfssl/wolfcrypt/sp_int.h index e9eacf42e..bd6fc3203 100644 --- a/wolfssl/wolfcrypt/sp_int.h +++ b/wolfssl/wolfcrypt/sp_int.h @@ -788,11 +788,19 @@ typedef struct sp_ecc_ctx { #define MP_INT_NEXT(t, cnt) \ (sp_int*)(((byte*)(t)) + MP_INT_SIZEOF(cnt)) +#define MP_INT_SIZEOF_DIGITS(cnt) (MP_INT_SIZEOF(cnt) / sizeof(sp_int_digit)) /* Calculate the number of words required to support a number of bits. */ #define MP_BITS_CNT(bits) \ ((unsigned int)(((((bits) + SP_WORD_SIZE - 1) / SP_WORD_SIZE) * 2 + 1))) +#if !defined(WOLFSSL_SP_NO_DYN_STACK) && defined(__STDC_VERSION__) && \ + (__STDC_VERSION__ >= 199901L) && \ + (defined(WOLFSSL_SP_NO_MALLOC) || \ + !(defined(WOLFSSL_SMALL_STACK) || defined(SP_ALLOC))) + #define WOLFSSL_SP_DYN_STACK +#endif + #ifdef WOLFSSL_SMALL_STACK /* * Dynamic memory allocation of mp_int. @@ -823,26 +831,25 @@ while (0) /* * Static allocation of mp_int. */ -#if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) && \ - !defined(WOLFSSL_SP_NO_DYN_STACK) +#ifdef WOLFSSL_SP_DYN_STACK /* Declare a dynamically allocated mp_int. */ -#define DECL_MP_INT_SIZE_DYN(name, bits, max) \ - unsigned char name##d[MP_INT_SIZEOF(MP_BITS_CNT(bits))]; \ +#define DECL_MP_INT_SIZE_DYN(name, bits, max) \ + sp_int_digit name##d[MP_INT_SIZEOF_DIGITS(MP_BITS_CNT(bits))]; \ sp_int* (name) = (sp_int*)name##d #elif defined(__cplusplus) /* C++ doesn't tolerate parentheses around "name" (-Wparentheses) */ -#define DECL_MP_INT_SIZE_DYN(name, bits, max) \ - unsigned char name##d[MP_INT_SIZEOF(MP_BITS_CNT(max))]; \ +#define DECL_MP_INT_SIZE_DYN(name, bits, max) \ + sp_int_digit name##d[MP_INT_SIZEOF_DIGITS(MP_BITS_CNT(max))]; \ sp_int* name = (sp_int*)name##d #else /* Declare a dynamically allocated mp_int. */ -#define DECL_MP_INT_SIZE_DYN(name, bits, max) \ - unsigned char name##d[MP_INT_SIZEOF(MP_BITS_CNT(max))]; \ +#define DECL_MP_INT_SIZE_DYN(name, bits, max) \ + sp_int_digit name##d[MP_INT_SIZEOF_DIGITS(MP_BITS_CNT(max))]; \ sp_int* (name) = (sp_int*)name##d #endif /* Declare a statically allocated mp_int. */ -#define DECL_MP_INT_SIZE(name, bits) \ - unsigned char name##d[MP_INT_SIZEOF(MP_BITS_CNT(bits))]; \ +#define DECL_MP_INT_SIZE(name, bits) \ + sp_int_digit name##d[MP_INT_SIZEOF_DIGITS(MP_BITS_CNT(bits))]; \ sp_int* (name) = (sp_int*)name##d /* Zero out mp_int of minimal size. */ #define NEW_MP_INT_SIZE(name, bits, heap, type) \ @@ -910,7 +917,7 @@ typedef struct sp_int { struct WC_BIGINT raw; #endif /** Data of number. */ - sp_int_digit dp[SP_INT_DIGITS]; + XALIGNED(SP_WORD_SIZE / 8) sp_int_digit dp[SP_INT_DIGITS]; } sp_int; typedef struct sp_int_minimal { @@ -927,11 +934,14 @@ typedef struct sp_int_minimal { struct WC_BIGINT raw; #endif /** First digit of number. */ - sp_int_digit dp[1]; + XALIGNED(SP_WORD_SIZE / 8) sp_int_digit dp[1]; } sp_int_minimal; +/* MP_INT_SIZEOF_DIGITS() requires that sizeof(sp_int) is a multiple of + * sizeof(sp_int_digit). + */ +wc_static_assert(sizeof(struct sp_int) % sizeof(sp_int_digit) == 0); wc_static_assert(sizeof(struct sp_int_minimal) % sizeof(sp_int_digit) == 0); -#define MP_INT_SIZEOF_DIGITS(cnt) (MP_INT_SIZEOF(cnt) / sizeof(sp_int_digit)) /* Multi-precision integer type is SP integer type. */ typedef sp_int mp_int;