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lrstewartlrstewart
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refactor: move stuffer hex methods out of testlib (#4653)
1 parent 138e3ec commit 4b15a4b

14 files changed

+801
-321
lines changed

‎error/s2n_errno.c

+1
Original file line numberDiff line numberDiff line change
@@ -312,6 +312,7 @@ static const char *no_such_error = "Internal s2n error";
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ERR_ENTRY(S2N_ERR_MISSING_CLIENT_CERT, "Server requires client certificate") \
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ERR_ENTRY(S2N_ERR_INVALID_SERIALIZED_CONNECTION, "Serialized connection is invalid"); \
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ERR_ENTRY(S2N_ERR_TOO_MANY_CAS, "Too many certificate authorities in trust store"); \
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ERR_ENTRY(S2N_ERR_BAD_HEX, "Could not parse malformed hex string"); \
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/* clang-format on */
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#define ERR_STR_CASE(ERR, str) \

‎error/s2n_errno.h

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Original file line numberDiff line numberDiff line change
@@ -237,6 +237,7 @@ typedef enum {
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S2N_ERR_LIBCRYPTO_VERSION_NUMBER_MISMATCH,
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S2N_ERR_LIBCRYPTO_VERSION_NAME_MISMATCH,
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S2N_ERR_OSSL_PROVIDER,
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S2N_ERR_BAD_HEX,
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S2N_ERR_TEST_ASSERTION,
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S2N_ERR_T_INTERNAL_END,
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‎stuffer/s2n_stuffer.h

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@@ -154,6 +154,23 @@ int S2N_RESULT_MUST_USE s2n_stuffer_write_vector_size(struct s2n_stuffer_reserva
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/* Copy one stuffer to another */
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int s2n_stuffer_copy(struct s2n_stuffer *from, struct s2n_stuffer *to, uint32_t len);
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/* Convert between hex strings and raw bytes.
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*
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* When reading hex, the characters can be uppercase or lowercase.
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* When writing hex, lowercase characters are used.
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*
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* Examples:
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* "1234567890ABCdef" == [ 0x12, 0x34, 0x56, 0x78, 0x90, 0xab, 0xcd, 0xef ]
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* "FF" == 255 or [ 0xff ]
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* "0001" == 1 or [ 0x00, 0x01 ]
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*/
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S2N_RESULT s2n_stuffer_read_hex(struct s2n_stuffer *bytes_out, const struct s2n_blob *hex_in);
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S2N_RESULT s2n_stuffer_write_hex(struct s2n_stuffer *hex_out, const struct s2n_blob *bytes_in);
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S2N_RESULT s2n_stuffer_read_uint8_hex(struct s2n_stuffer *stuffer, uint8_t *u);
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S2N_RESULT s2n_stuffer_write_uint8_hex(struct s2n_stuffer *stuffer, uint8_t u);
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S2N_RESULT s2n_stuffer_read_uint16_hex(struct s2n_stuffer *stuffer, uint16_t *u);
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S2N_RESULT s2n_stuffer_write_uint16_hex(struct s2n_stuffer *stuffer, uint16_t u);
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/* Read and write base64 */
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int s2n_stuffer_read_base64(struct s2n_stuffer *stuffer, struct s2n_stuffer *out);
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int s2n_stuffer_write_base64(struct s2n_stuffer *stuffer, struct s2n_stuffer *in);

‎stuffer/s2n_stuffer_hex.c

+161
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,161 @@
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/*
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* Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
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*
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* Licensed under the Apache License, Version 2.0 (the "License").
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* You may not use this file except in compliance with the License.
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* A copy of the License is located at
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*
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* http://aws.amazon.com/apache2.0
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*
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* or in the "license" file accompanying this file. This file is distributed
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* on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
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* express or implied. See the License for the specific language governing
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* permissions and limitations under the License.
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*/
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#include "error/s2n_errno.h"
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#include "stuffer/s2n_stuffer.h"
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#include "utils/s2n_safety.h"
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static const uint8_t value_to_hex[16] = {
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'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'
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};
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static const uint8_t hex_to_value[] = {
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/* clang-format off */
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['0'] = 0, ['1'] = 1, ['2'] = 2, ['3'] = 3, ['4'] = 4,
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['5'] = 5, ['6'] = 6, ['7'] = 7, ['8'] = 8, ['9'] = 9,
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['a'] = 10, ['b'] = 11, ['c'] = 12, ['d'] = 13, ['e'] = 14, ['f'] = 15,
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['A'] = 10, ['B'] = 11, ['C'] = 12, ['D'] = 13, ['E'] = 14, ['F'] = 15,
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/* clang-format on */
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};
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static S2N_RESULT s2n_stuffer_hex_digit_from_char(uint8_t c, uint8_t *i)
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{
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RESULT_ENSURE(c < s2n_array_len(hex_to_value), S2N_ERR_BAD_HEX);
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/* Invalid characters map to 0 in hex_to_value, but so does '0'. */
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if (hex_to_value[c] == 0) {
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RESULT_ENSURE(c == '0', S2N_ERR_BAD_HEX);
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}
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*i = hex_to_value[c];
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return S2N_RESULT_OK;
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}
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S2N_RESULT s2n_stuffer_read_hex(struct s2n_stuffer *bytes_out, const struct s2n_blob *hex_in)
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{
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RESULT_PRECONDITION(s2n_stuffer_validate(bytes_out));
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RESULT_PRECONDITION(s2n_blob_validate(hex_in));
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size_t hex_size = hex_in->size;
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size_t bytes_size = hex_in->size / 2;
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RESULT_ENSURE(hex_size % 2 == 0, S2N_ERR_BAD_HEX);
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if (hex_size == 0) {
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return S2N_RESULT_OK;
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}
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RESULT_GUARD_POSIX(s2n_stuffer_reserve_space(bytes_out, bytes_size));
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uint8_t *out = bytes_out->blob.data + bytes_out->write_cursor;
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uint8_t *in = hex_in->data;
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for (size_t i = 0; i < bytes_size; i++) {
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uint8_t hex_high = 0, hex_low = 0;
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RESULT_GUARD(s2n_stuffer_hex_digit_from_char(in[(i * 2)], &hex_high));
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RESULT_GUARD(s2n_stuffer_hex_digit_from_char(in[(i * 2) + 1], &hex_low));
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out[i] = (hex_high * 16) + hex_low;
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}
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RESULT_GUARD_POSIX(s2n_stuffer_skip_write(bytes_out, bytes_size));
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return S2N_RESULT_OK;
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}
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S2N_RESULT s2n_stuffer_write_hex(struct s2n_stuffer *hex_out, const struct s2n_blob *bytes_in)
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{
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RESULT_PRECONDITION(s2n_stuffer_validate(hex_out));
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RESULT_PRECONDITION(s2n_blob_validate(bytes_in));
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size_t bytes_size = bytes_in->size;
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size_t hex_size = bytes_size * 2;
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RESULT_GUARD_POSIX(s2n_stuffer_reserve_space(hex_out, hex_size));
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uint8_t *out = hex_out->blob.data + hex_out->write_cursor;
81+
uint8_t *in = bytes_in->data;
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for (size_t i = 0; i < bytes_size; i++) {
84+
out[(i * 2)] = value_to_hex[(in[i] >> 4)];
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out[(i * 2) + 1] = value_to_hex[(in[i] & 0x0f)];
86+
}
87+
88+
RESULT_GUARD_POSIX(s2n_stuffer_skip_write(hex_out, hex_size));
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return S2N_RESULT_OK;
90+
}
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static S2N_RESULT s2n_stuffer_hex_read_n_bytes(struct s2n_stuffer *stuffer, uint8_t n, uint64_t *u)
93+
{
94+
RESULT_ENSURE_LTE(n, sizeof(uint64_t));
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RESULT_ENSURE_REF(u);
96+
97+
uint8_t hex_data[16] = { 0 };
98+
struct s2n_blob b = { 0 };
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RESULT_GUARD_POSIX(s2n_blob_init(&b, hex_data, n * 2));
100+
101+
RESULT_ENSURE_REF(stuffer);
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RESULT_ENSURE(s2n_stuffer_read(stuffer, &b) == S2N_SUCCESS, S2N_ERR_BAD_HEX);
103+
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/* Start with u = 0 */
105+
*u = 0;
106+
for (size_t i = 0; i < b.size; i++) {
107+
*u <<= 4;
108+
uint8_t hex = 0;
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RESULT_GUARD(s2n_stuffer_hex_digit_from_char(b.data[i], &hex));
110+
*u += hex;
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}
112+
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return S2N_RESULT_OK;
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}
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S2N_RESULT s2n_stuffer_read_uint16_hex(struct s2n_stuffer *stuffer, uint16_t *u)
117+
{
118+
RESULT_ENSURE_REF(u);
119+
uint64_t u64 = 0;
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RESULT_GUARD(s2n_stuffer_hex_read_n_bytes(stuffer, sizeof(uint16_t), &u64));
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RESULT_ENSURE_LTE(u64, UINT16_MAX);
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*u = u64;
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return S2N_RESULT_OK;
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}
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S2N_RESULT s2n_stuffer_read_uint8_hex(struct s2n_stuffer *stuffer, uint8_t *u)
127+
{
128+
RESULT_ENSURE_REF(u);
129+
uint64_t u64 = 0;
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RESULT_GUARD(s2n_stuffer_hex_read_n_bytes(stuffer, sizeof(uint8_t), &u64));
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RESULT_ENSURE_LTE(u64, UINT8_MAX);
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*u = u64;
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return S2N_RESULT_OK;
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}
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static S2N_RESULT s2n_stuffer_hex_write_n_bytes(struct s2n_stuffer *stuffer, uint8_t n, uint64_t u)
137+
{
138+
RESULT_ENSURE_LTE(n, sizeof(uint64_t));
139+
140+
uint8_t hex_data[16] = { 0 };
141+
struct s2n_blob b = { 0 };
142+
RESULT_GUARD_POSIX(s2n_blob_init(&b, hex_data, n * 2));
143+
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for (size_t i = b.size; i > 0; i--) {
145+
b.data[i - 1] = value_to_hex[u & 0x0f];
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u >>= 4;
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}
148+
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RESULT_GUARD_POSIX(s2n_stuffer_write(stuffer, &b));
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return S2N_RESULT_OK;
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}
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S2N_RESULT s2n_stuffer_write_uint16_hex(struct s2n_stuffer *stuffer, uint16_t u)
154+
{
155+
return s2n_stuffer_hex_write_n_bytes(stuffer, sizeof(uint16_t), u);
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}
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S2N_RESULT s2n_stuffer_write_uint8_hex(struct s2n_stuffer *stuffer, uint8_t u)
159+
{
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return s2n_stuffer_hex_write_n_bytes(stuffer, sizeof(uint8_t), u);
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}

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