33 static ossl_inline unsigned int constant_time_msb(unsigned int a);
35 static ossl_inline uint32_t constant_time_msb_32(uint32_t a);
37 static ossl_inline uint64_t constant_time_msb_64(uint64_t a);
40 static ossl_inline unsigned int constant_time_lt(unsigned int a,
43 static ossl_inline unsigned char constant_time_lt_8(unsigned int a,
46 static ossl_inline uint64_t constant_time_lt_64(uint64_t a, uint64_t b);
49 static ossl_inline unsigned int constant_time_ge(unsigned int a,
52 static ossl_inline unsigned char constant_time_ge_8(unsigned int a,
56 static ossl_inline unsigned int constant_time_is_zero(unsigned int a);
58 static ossl_inline unsigned char constant_time_is_zero_8(unsigned int a);
60 static ossl_inline uint32_t constant_time_is_zero_32(uint32_t a);
63 static ossl_inline unsigned int constant_time_eq(unsigned int a,
66 static ossl_inline unsigned char constant_time_eq_8(unsigned int a,
69 static ossl_inline unsigned int constant_time_eq_int(int a, int b);
71 static ossl_inline unsigned char constant_time_eq_int_8(int a, int b);
81                                                      unsigned int a,
85                                                         unsigned char a,
89 static ossl_inline uint32_t constant_time_select_32(uint32_t mask, uint32_t a,
93 static ossl_inline uint64_t constant_time_select_64(uint64_t mask, uint64_t a,
96 static ossl_inline int constant_time_select_int(unsigned int mask, int a,
100 static ossl_inline unsigned int constant_time_msb(unsigned int a)  in constant_time_msb()  argument
102     return 0 - (a >> (sizeof(a) * 8 - 1));  in constant_time_msb()
106 static ossl_inline uint32_t constant_time_msb_32(uint32_t a)  in constant_time_msb_32()  argument
108     return 0 - (a >> 31);  in constant_time_msb_32()
111 static ossl_inline uint64_t constant_time_msb_64(uint64_t a)  in constant_time_msb_64()  argument
113     return 0 - (a >> 63);  in constant_time_msb_64()
116 static ossl_inline size_t constant_time_msb_s(size_t a)  in constant_time_msb_s()  argument
118     return 0 - (a >> (sizeof(a) * 8 - 1));  in constant_time_msb_s()
121 static ossl_inline unsigned int constant_time_lt(unsigned int a,  in constant_time_lt()  argument
124     return constant_time_msb(a ^ ((a ^ b) | ((a - b) ^ b)));  in constant_time_lt()
127 static ossl_inline size_t constant_time_lt_s(size_t a, size_t b)  in constant_time_lt_s()  argument
129     return constant_time_msb_s(a ^ ((a ^ b) | ((a - b) ^ b)));  in constant_time_lt_s()
132 static ossl_inline unsigned char constant_time_lt_8(unsigned int a,  in constant_time_lt_8()  argument
135     return (unsigned char)constant_time_lt(a, b);  in constant_time_lt_8()
138 static ossl_inline uint64_t constant_time_lt_64(uint64_t a, uint64_t b)  in constant_time_lt_64()  argument
140     return constant_time_msb_64(a ^ ((a ^ b) | ((a - b) ^ b)));  in constant_time_lt_64()
144 static ossl_inline BN_ULONG constant_time_msb_bn(BN_ULONG a)  in constant_time_msb_bn()  argument
146     return 0 - (a >> (sizeof(a) * 8 - 1));  in constant_time_msb_bn()
149 static ossl_inline BN_ULONG constant_time_lt_bn(BN_ULONG a, BN_ULONG b)  in constant_time_lt_bn()  argument
151     return constant_time_msb_bn(a ^ ((a ^ b) | ((a - b) ^ b)));  in constant_time_lt_bn()
154 static ossl_inline BN_ULONG constant_time_is_zero_bn(BN_ULONG a)  in constant_time_is_zero_bn()  argument
156     return constant_time_msb_bn(~a & (a - 1));  in constant_time_is_zero_bn()
159 static ossl_inline BN_ULONG constant_time_eq_bn(BN_ULONG a,  in constant_time_eq_bn()  argument
162     return constant_time_is_zero_bn(a ^ b);  in constant_time_eq_bn()
166 static ossl_inline unsigned int constant_time_ge(unsigned int a,  in constant_time_ge()  argument
169     return ~constant_time_lt(a, b);  in constant_time_ge()
172 static ossl_inline size_t constant_time_ge_s(size_t a, size_t b)  in constant_time_ge_s()  argument
174     return ~constant_time_lt_s(a, b);  in constant_time_ge_s()
177 static ossl_inline unsigned char constant_time_ge_8(unsigned int a,  in constant_time_ge_8()  argument
180     return (unsigned char)constant_time_ge(a, b);  in constant_time_ge_8()
183 static ossl_inline unsigned char constant_time_ge_8_s(size_t a, size_t b)  in constant_time_ge_8_s()  argument
185     return (unsigned char)constant_time_ge_s(a, b);  in constant_time_ge_8_s()
188 static ossl_inline unsigned int constant_time_is_zero(unsigned int a)  in constant_time_is_zero()  argument
190     return constant_time_msb(~a & (a - 1));  in constant_time_is_zero()
193 static ossl_inline size_t constant_time_is_zero_s(size_t a)  in constant_time_is_zero_s()  argument
195     return constant_time_msb_s(~a & (a - 1));  in constant_time_is_zero_s()
198 static ossl_inline unsigned char constant_time_is_zero_8(unsigned int a)  in constant_time_is_zero_8()  argument
200     return (unsigned char)constant_time_is_zero(a);  in constant_time_is_zero_8()
203 static ossl_inline uint32_t constant_time_is_zero_32(uint32_t a)  in constant_time_is_zero_32()  argument
205     return constant_time_msb_32(~a & (a - 1));  in constant_time_is_zero_32()
208 static ossl_inline uint64_t constant_time_is_zero_64(uint64_t a)  in constant_time_is_zero_64()  argument
210     return constant_time_msb_64(~a & (a - 1));  in constant_time_is_zero_64()
213 static ossl_inline unsigned int constant_time_eq(unsigned int a,  in constant_time_eq()  argument
216     return constant_time_is_zero(a ^ b);  in constant_time_eq()
219 static ossl_inline size_t constant_time_eq_s(size_t a, size_t b)  in constant_time_eq_s()  argument
221     return constant_time_is_zero_s(a ^ b);  in constant_time_eq_s()
224 static ossl_inline unsigned char constant_time_eq_8(unsigned int a,  in constant_time_eq_8()  argument
227     return (unsigned char)constant_time_eq(a, b);  in constant_time_eq_8()
230 static ossl_inline unsigned char constant_time_eq_8_s(size_t a, size_t b)  in constant_time_eq_8_s()  argument
232     return (unsigned char)constant_time_eq_s(a, b);  in constant_time_eq_8_s()
235 static ossl_inline unsigned int constant_time_eq_int(int a, int b)  in constant_time_eq_int()  argument
237     return constant_time_eq((unsigned)(a), (unsigned)(b));  in constant_time_eq_int()
240 static ossl_inline unsigned char constant_time_eq_int_8(int a, int b)  in constant_time_eq_int_8()  argument
242     return constant_time_eq_8((unsigned)(a), (unsigned)(b));  in constant_time_eq_int_8()
252 static ossl_inline unsigned int value_barrier(unsigned int a)  in value_barrier()  argument
256     __asm__("" : "=r"(r) : "0"(a));  in value_barrier()
258     volatile unsigned int r = a;  in value_barrier()
264 static ossl_inline uint32_t value_barrier_32(uint32_t a)  in value_barrier_32()  argument
268     __asm__("" : "=r"(r) : "0"(a));  in value_barrier_32()
270     volatile uint32_t r = a;  in value_barrier_32()
276 static ossl_inline uint64_t value_barrier_64(uint64_t a)  in value_barrier_64()  argument
280     __asm__("" : "=r"(r) : "0"(a));  in value_barrier_64()
282     volatile uint64_t r = a;  in value_barrier_64()
288 static ossl_inline size_t value_barrier_s(size_t a)  in value_barrier_s()  argument
292     __asm__("" : "=r"(r) : "0"(a));  in value_barrier_s()
294     volatile size_t r = a;  in value_barrier_s()
300                                                      unsigned int a,  in constant_time_select()  argument
303     return (value_barrier(mask) & a) | (value_barrier(~mask) & b);  in constant_time_select()
307                                                  size_t a,  in constant_time_select_s()  argument
310     return (value_barrier_s(mask) & a) | (value_barrier_s(~mask) & b);  in constant_time_select_s()
314                                                         unsigned char a,  in constant_time_select_8()  argument
317     return (unsigned char)constant_time_select(mask, a, b);  in constant_time_select_8()
320 static ossl_inline int constant_time_select_int(unsigned int mask, int a,  in constant_time_select_int()  argument
323     return (int)constant_time_select(mask, (unsigned)(a), (unsigned)(b));  in constant_time_select_int()
326 static ossl_inline int constant_time_select_int_s(size_t mask, int a, int b)  in constant_time_select_int_s()  argument
328     return (int)constant_time_select((unsigned)mask, (unsigned)(a),  in constant_time_select_int_s()
332 static ossl_inline uint32_t constant_time_select_32(uint32_t mask, uint32_t a,  in constant_time_select_32()  argument
335     return (value_barrier_32(mask) & a) | (value_barrier_32(~mask) & b);  in constant_time_select_32()
338 static ossl_inline uint64_t constant_time_select_64(uint64_t mask, uint64_t a,  in constant_time_select_64()  argument
341     return (value_barrier_64(mask) & a) | (value_barrier_64(~mask) & b);  in constant_time_select_64()
354 static ossl_inline void constant_time_cond_swap_32(uint32_t mask, uint32_t *a,  in constant_time_cond_swap_32()  argument
357     uint32_t xor = *a ^ *b;  in constant_time_cond_swap_32()
360     *a ^= xor;  in constant_time_cond_swap_32()
374 static ossl_inline void constant_time_cond_swap_64(uint64_t mask, uint64_t *a,  in constant_time_cond_swap_64()  argument
377     uint64_t xor = *a ^ *b;  in constant_time_cond_swap_64()
380     *a ^= xor;  in constant_time_cond_swap_64()
397                                                      unsigned char *a,  in constant_time_cond_swap_buff()  argument
405         tmp = a[i] ^ b[i];  in constant_time_cond_swap_buff()
407         a[i] ^= tmp;  in constant_time_cond_swap_buff()