From: Andy Polyakov Date: Fri, 20 Jul 2018 11:15:48 +0000 (+0200) Subject: crypto/cryptlib.c: make OPENSS_cpuid_setup safe to use as constructor. X-Git-Tag: OpenSSL_1_1_0i~21 X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=811162832e875576c13139493d949b3157a1c8cf;p=oweals%2Fopenssl.git crypto/cryptlib.c: make OPENSS_cpuid_setup safe to use as constructor. Reviewed-by: Rich Salz (Merged from https://github.com/openssl/openssl/pull/6799) (cherry picked from commit b86d57bb0b23253c720db38ab18ca97cb888f701) Resolved conflicts: crypto/cryptlib.c --- diff --git a/crypto/cryptlib.c b/crypto/cryptlib.c index bf73244394..3b878cd0c2 100644 --- a/crypto/cryptlib.c +++ b/crypto/cryptlib.c @@ -23,29 +23,97 @@ extern unsigned int OPENSSL_ia32cap_P[4]; # if defined(OPENSSL_CPUID_OBJ) && !defined(OPENSSL_NO_ASM) && !defined(I386_ONLY) -#include + +/* + * Purpose of these minimalistic and character-type-agnostic subroutines + * is to break dependency on MSVCRT (on Windows) and locale. This makes + * OPENSSL_cpuid_setup safe to use as "constructor". "Character-type- + * agnostic" means that they work with either wide or 8-bit characters, + * exploiting the fact that first 127 characters can be simply casted + * between the sets, while the rest would be simply rejected by ossl_is* + * subroutines. + */ +# ifdef _WIN32 +typedef WCHAR variant_char; + +static variant_char *ossl_getenv(const char *name) +{ + /* + * Since we pull only one environment variable, it's simpler to + * to just ignore |name| and use equivalent wide-char L-literal. + * As well as to ignore excessively long values... + */ + static WCHAR value[48]; + DWORD len = GetEnvironmentVariableW(L"OPENSSL_ia32cap", value, 48); + + return (len > 0 && len < 48) ? value : NULL; +} +# else +typedef char variant_char; +# define ossl_getenv getenv +# endif + +static int todigit(variant_char c) +{ + if (c >= '0' && c <= '9') + return c - '0'; + else if (c >= 'A' && c <= 'F') + return c - 'A' + 10; + else if (c >= 'a' && c <= 'f') + return c - 'a' + 10; + + /* return largest base value to make caller terminate the loop */ + return 16; +} + +static uint64_t ossl_strtouint64(const variant_char *str) +{ + uint64_t ret = 0; + unsigned int digit, base = 10; + + if (*str == '0') { + base = 8, str++; + if (*str == 'x' || *str == 'X') + base = 16, str++; + } + + while((digit = todigit(*str++)) < base) + ret = ret * base + digit; + + return ret; +} + +static variant_char *ossl_strchr(const variant_char *str, char srch) +{ variant_char c; + + while((c = *str)) { + if (c == srch) + return (variant_char *)str; + str++; + } + + return NULL; +} + # define OPENSSL_CPUID_SETUP typedef uint64_t IA32CAP; + void OPENSSL_cpuid_setup(void) { static int trigger = 0; IA32CAP OPENSSL_ia32_cpuid(unsigned int *); IA32CAP vec; - char *env; + const variant_char *env; if (trigger) return; trigger = 1; - if ((env = getenv("OPENSSL_ia32cap"))) { + if ((env = ossl_getenv("OPENSSL_ia32cap")) != NULL) { int off = (env[0] == '~') ? 1 : 0; -# if defined(_WIN32) - if (!sscanf(env + off, "%I64i", &vec)) - vec = strtoul(env + off, NULL, 0); -# else - if (!sscanf(env + off, "%lli", (long long *)&vec)) - vec = strtoul(env + off, NULL, 0); -# endif + + vec = ossl_strtouint64(env + off); + if (off) { IA32CAP mask = vec; vec = OPENSSL_ia32_cpuid(OPENSSL_ia32cap_P) & ~mask; @@ -64,15 +132,17 @@ void OPENSSL_cpuid_setup(void) vec = OPENSSL_ia32_cpuid(OPENSSL_ia32cap_P); } - if ((env = strchr(env, ':'))) { - unsigned int vecx; + if ((env = ossl_strchr(env, ':')) != NULL) { + IA32CAP vecx; + env++; off = (env[0] == '~') ? 1 : 0; - vecx = strtoul(env + off, NULL, 0); - if (off) - OPENSSL_ia32cap_P[2] &= ~vecx; - else - OPENSSL_ia32cap_P[2] = vecx; + vecx = ossl_strtouint64(env + off); + if (off) { + OPENSSL_ia32cap_P[2] &= ~(unsigned int)vecx; + } else { + OPENSSL_ia32cap_P[2] = (unsigned int)vecx; + } } else { OPENSSL_ia32cap_P[2] = 0; }