diff options
| -rw-r--r-- | common.h | 6 | ||||
| -rw-r--r-- | libar2.h | 2 | ||||
| -rw-r--r-- | libar2_erase.c | 3 | ||||
| -rw-r--r-- | libar2_hash.c | 5 | ||||
| -rw-r--r-- | libar2_hash_buf_size.3 | 9 | ||||
| -rw-r--r-- | libar2_hash_buf_size.c | 7 | ||||
| -rw-r--r-- | test.c | 67 |
7 files changed, 90 insertions, 9 deletions
@@ -28,6 +28,11 @@ #endif +#if defined(__GNUC__) +# define LIBAR2_WEAKLY_LINKED__ __attribute__((weak)) +#endif + + #ifndef CACHE_LINE_SIZE # define CACHE_LINE_SIZE 256 /* better with larger than actual than smaller than actual */ #endif @@ -48,6 +53,7 @@ # endif #endif + #define ELEMSOF(ARR) (sizeof(ARR) / sizeof(*(ARR))) #define MAX(A, B) ((A) > (B) ? (A) : (B)) @@ -671,7 +671,7 @@ int libar2_hash(void *hash, void *msg, size_t msglen, struct libar2_argon2_param * result is too large */ LIBAR2_PUBLIC__ LIBAR2_NONNULL__(1) -size_t libar2_hash_buf_size(struct libar2_argon2_parameters *params); +size_t libar2_hash_buf_size(const struct libar2_argon2_parameters *params); #if defined(__clang__) # pragma clang diagnostic pop diff --git a/libar2_erase.c b/libar2_erase.c index 6760390..f4fa2d3 100644 --- a/libar2_erase.c +++ b/libar2_erase.c @@ -23,6 +23,9 @@ __attribute__((optnone)) __attribute__((optimize("O0"))) # endif #endif +#ifdef LIBAR2_WEAKLY_LINKED__ +LIBAR2_WEAKLY_LINKED__ +#endif void libar2_erase(volatile void *mem_, size_t size) { diff --git a/libar2_hash.c b/libar2_hash.c index 6ce898c..757dbdf 100644 --- a/libar2_hash.c +++ b/libar2_hash.c @@ -487,7 +487,7 @@ libar2_hash(void *hash, void *msg, size_t msglen, struct libar2_argon2_parameter unsigned char block[1024 + 128], hash0[256]; uint_least32_t blocks, seglen, lanelen; struct block *memory; - size_t i, p, s, nthreads, ts[16], ti, tn; + size_t i, p, s, nthreads, ts[16], ti, tn, bufsize; struct threaded_fill_segments_params *tparams = NULL; uint_least64_t *sbox = NULL; /* This is 8K large (assuming support for uint64_t), so we allocate it dynamically */ @@ -596,6 +596,9 @@ libar2_hash(void *hash, void *msg, size_t msglen, struct libar2_argon2_parameter memxor(&memory[lanelen - 1], &memory[i * lanelen + lanelen - 1], sizeof(*memory)); store_block(block, &memory[lanelen - 1]); argon2_blake2b_exthash(hash, params->hashlen, block, 1024); + bufsize = libar2_hash_buf_size(params); + if (bufsize) /* should never be 0 as that would indicate the user provided a too small buffer */ + libar2_erase(&((char *)hash)[params->hashlen], bufsize - params->hashlen); ERASE_ARRAY(block); if (sbox) diff --git a/libar2_hash_buf_size.3 b/libar2_hash_buf_size.3 index dcb8285..66cd05d 100644 --- a/libar2_hash_buf_size.3 +++ b/libar2_hash_buf_size.3 @@ -6,7 +6,7 @@ libar2_hash_buf_size - Determine require output buffer size .nf #include <libar2.h> -size_t libar2_hash_buf_size(struct libar2_argon2_parameters *\fIparams\fP); +size_t libar2_hash_buf_size(const struct libar2_argon2_parameters *\fIparams\fP); .fi .PP Link with @@ -26,10 +26,11 @@ may not be .PP The return value is .I params->hashlen -if this number is 64 or less, a multiple of 128 -that is around twice as large as +if this number is 64 or less, otherwise the +it will be larger than .I params->hashlen -(can be a bit more). +but no larger than +.IR "(params->hashlen + 63)" . .SH RETURN VALUES The diff --git a/libar2_hash_buf_size.c b/libar2_hash_buf_size.c index 109969f..3010a8a 100644 --- a/libar2_hash_buf_size.c +++ b/libar2_hash_buf_size.c @@ -3,13 +3,14 @@ size_t -libar2_hash_buf_size(struct libar2_argon2_parameters *params) +libar2_hash_buf_size(const struct libar2_argon2_parameters *params) { if (params->hashlen <= 64) return params->hashlen; - if (params->hashlen > SIZE_MAX / 128 * 64 - 31) { + if (params->hashlen > SIZE_MAX - 31 || + ((params->hashlen + 31) | 31) == SIZE_MAX) { errno = EOVERFLOW; return 0; } - return (params->hashlen + 31) / 64 * 128; + return ((params->hashlen + 31) | 31) + 1; } @@ -780,6 +780,68 @@ check_libar2_hash(void) } +#ifdef LIBAR2_WEAKLY_LINKED__ + +void +libar2_erase(volatile void *mem, size_t size) +{ + (void) mem; + (void) size; +} + +static void +check_libar2_hash_buf_size(void) +{ + struct libar2_argon2_parameters params; + char pwd[512], output[2049], *doutput; + unsigned char salt[LIBAR2_MIN_SALTLEN]; + size_t size, size0, size1, i; + volatile char x, *avoid_code_elimination = &x; + + errno = 0; + + memset(¶ms, 0, sizeof(params)); + memset(salt, 0, sizeof(salt)); + params.saltlen = LIBAR2_MIN_SALTLEN; + params.salt = salt; + params.m_cost = LIBAR2_MIN_M_COST; + params.t_cost = LIBAR2_MIN_T_COST; + params.lanes = LIBAR2_MIN_LANES; + params.type = LIBAR2_ARGON2I; + + for (params.hashlen = LIBAR2_MIN_HASHLEN; params.hashlen < sizeof(output) - 513; params.hashlen++) { + memset(output, 0, sizeof(output)); + assert(!libar2_hash(output, pwd, 0, ¶ms, &ctx_st)); + assert(errno == 0); + for (size0 = sizeof(output); size0; size0--) + if (output[size0 - 1] != 0) + break; + + memset(output, 1, sizeof(output)); + assert(!libar2_hash(output, pwd, 0, ¶ms, &ctx_st)); + assert(errno == 0); + for (size1 = sizeof(output); size1; size1--) + if (output[size1 - 1] != 1) + break; + + size = MAX(size0, size1); + if (libar2_hash_buf_size(¶ms) != size || size > params.hashlen + 63) + fprintf(stderr, "At hashlen = %zu (expect %zu)\n", params.hashlen, size); + assert(size <= params.hashlen + 63); + assert_zueq(libar2_hash_buf_size(¶ms), size); + + doutput = malloc(size); + assert(!libar2_hash(doutput, pwd, 0, ¶ms, &ctx_st)); + assert(errno == 0); + for(i = 0; i < params.hashlen; i++) + *avoid_code_elimination ^= doutput[i]; + free(doutput); + } +} + +#endif + + int main(void) { @@ -793,5 +855,10 @@ main(void) check_libar2_encode_params_libar2_decode_params(); check_libar2_validate_params(); check_libar2_hash(); + +#ifdef LIBAR2_WEAKLY_LINKED__ + check_libar2_hash_buf_size(); +#endif + return 0; } |