Add support for ECDSA P-256 with SHA256
This adds a small EC library that is capable of verifying a signature of
SHA256 with ECDSA on the NIST P-256 curve.
Change-Id: I2a16639c92a77e8e4783c47ffbc56676de56eb59
diff --git a/libmincrypt/test/ecdsa_test.c b/libmincrypt/test/ecdsa_test.c
new file mode 100644
index 0000000..b5a7b3a
--- /dev/null
+++ b/libmincrypt/test/ecdsa_test.c
@@ -0,0 +1,278 @@
+/*
+ * Copyright 2013 The Android Open Source Project
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * * Neither the name of Google Inc. nor the names of its contributors may
+ * be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY Google Inc. ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
+ * EVENT SHALL Google Inc. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <stdio.h>
+#include <ctype.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "mincrypt/p256.h"
+#include "mincrypt/p256_ecdsa.h"
+#include "mincrypt/sha256.h"
+
+/**
+ * Messages signed using:
+ *
+-----BEGIN EC PRIVATE KEY-----
+MHcCAQEEIDw6UiziVMbjlfSpOAIpA2tcL+v1OlznZLnpadO8BGi1oAoGCCqGSM49
+AwEHoUQDQgAEZw7VAOjAXYRFuhZWYBgjahdOvkwcAnjGkxQWytZW+iS1hI3ZGE24
+6XmNka9IGxAgj2n/ip+MuZJMFoJ9DRea3g==
+-----END EC PRIVATE KEY-----
+ */
+
+p256_int key_x = {
+ .a = {0xd656fa24u, 0x931416cau, 0x1c0278c6u, 0x174ebe4cu,
+ 0x6018236au, 0x45ba1656u, 0xe8c05d84u, 0x670ed500u}
+};
+p256_int key_y = {
+ .a = {0x0d179adeu, 0x4c16827du, 0x9f8cb992u, 0x8f69ff8au,
+ 0x481b1020u, 0x798d91afu, 0x184db8e9u, 0xb5848dd9u}
+};
+
+char* message_1 =
+ "f4 5d 55 f3 55 51 e9 75 d6 a8 dc 7e a9 f4 88 59"
+ "39 40 cc 75 69 4a 27 8f 27 e5 78 a1 63 d8 39 b3"
+ "40 40 84 18 08 cf 9c 58 c9 b8 72 8b f5 f9 ce 8e"
+ "e8 11 ea 91 71 4f 47 ba b9 2d 0f 6d 5a 26 fc fe"
+ "ea 6c d9 3b 91 0c 0a 2c 96 3e 64 eb 18 23 f1 02"
+ "75 3d 41 f0 33 59 10 ad 3a 97 71 04 f1 aa f6 c3"
+ "74 27 16 a9 75 5d 11 b8 ee d6 90 47 7f 44 5c 5d"
+ "27 20 8b 2e 28 43 30 fa 3d 30 14 23 fa 7f 2d 08"
+ "6e 0a d0 b8 92 b9 db 54 4e 45 6d 3f 0d ab 85 d9"
+ "53 c1 2d 34 0a a8 73 ed a7 27 c8 a6 49 db 7f a6"
+ "37 40 e2 5e 9a f1 53 3b 30 7e 61 32 99 93 11 0e"
+ "95 19 4e 03 93 99 c3 82 4d 24 c5 1f 22 b2 6b de"
+ "10 24 cd 39 59 58 a2 df eb 48 16 a6 e8 ad ed b5"
+ "0b 1f 6b 56 d0 b3 06 0f f0 f1 c4 cb 0d 0e 00 1d"
+ "d5 9d 73 be 12";
+
+char* signature_1 =
+ "30 44 02 20 43 18 fc eb 3b a8 3a a8 a3 cf 41 b7"
+ "81 4a f9 01 e1 8b 6e 95 c1 3a 83 25 9e a5 2e 66"
+ "7c 98 25 d9 02 20 54 f3 7f 5a e9 36 9c a2 f0 51"
+ "e0 6e 78 48 60 a3 f9 8a d5 2c 37 5a 0a 29 c9 f7"
+ "ea 57 7e 88 46 12";
+
+// Same as signature 1, but with leading zeroes.
+char* message_2 =
+ "f4 5d 55 f3 55 51 e9 75 d6 a8 dc 7e a9 f4 88 59"
+ "39 40 cc 75 69 4a 27 8f 27 e5 78 a1 63 d8 39 b3"
+ "40 40 84 18 08 cf 9c 58 c9 b8 72 8b f5 f9 ce 8e"
+ "e8 11 ea 91 71 4f 47 ba b9 2d 0f 6d 5a 26 fc fe"
+ "ea 6c d9 3b 91 0c 0a 2c 96 3e 64 eb 18 23 f1 02"
+ "75 3d 41 f0 33 59 10 ad 3a 97 71 04 f1 aa f6 c3"
+ "74 27 16 a9 75 5d 11 b8 ee d6 90 47 7f 44 5c 5d"
+ "27 20 8b 2e 28 43 30 fa 3d 30 14 23 fa 7f 2d 08"
+ "6e 0a d0 b8 92 b9 db 54 4e 45 6d 3f 0d ab 85 d9"
+ "53 c1 2d 34 0a a8 73 ed a7 27 c8 a6 49 db 7f a6"
+ "37 40 e2 5e 9a f1 53 3b 30 7e 61 32 99 93 11 0e"
+ "95 19 4e 03 93 99 c3 82 4d 24 c5 1f 22 b2 6b de"
+ "10 24 cd 39 59 58 a2 df eb 48 16 a6 e8 ad ed b5"
+ "0b 1f 6b 56 d0 b3 06 0f f0 f1 c4 cb 0d 0e 00 1d"
+ "d5 9d 73 be 12";
+
+char* signature_2 =
+ "30 46 02 21 00 43 18 fc eb 3b a8 3a a8 a3 cf 41 b7"
+ "81 4a f9 01 e1 8b 6e 95 c1 3a 83 25 9e a5 2e 66"
+ "7c 98 25 d9 02 21 00 54 f3 7f 5a e9 36 9c a2 f0 51"
+ "e0 6e 78 48 60 a3 f9 8a d5 2c 37 5a 0a 29 c9 f7"
+ "ea 57 7e 88 46 12";
+
+// Excessive zeroes on the signature
+char* message_3 =
+ "f4 5d 55 f3 55 51 e9 75 d6 a8 dc 7e a9 f4 88 59"
+ "39 40 cc 75 69 4a 27 8f 27 e5 78 a1 63 d8 39 b3"
+ "40 40 84 18 08 cf 9c 58 c9 b8 72 8b f5 f9 ce 8e"
+ "e8 11 ea 91 71 4f 47 ba b9 2d 0f 6d 5a 26 fc fe"
+ "ea 6c d9 3b 91 0c 0a 2c 96 3e 64 eb 18 23 f1 02"
+ "75 3d 41 f0 33 59 10 ad 3a 97 71 04 f1 aa f6 c3"
+ "74 27 16 a9 75 5d 11 b8 ee d6 90 47 7f 44 5c 5d"
+ "27 20 8b 2e 28 43 30 fa 3d 30 14 23 fa 7f 2d 08"
+ "6e 0a d0 b8 92 b9 db 54 4e 45 6d 3f 0d ab 85 d9"
+ "53 c1 2d 34 0a a8 73 ed a7 27 c8 a6 49 db 7f a6"
+ "37 40 e2 5e 9a f1 53 3b 30 7e 61 32 99 93 11 0e"
+ "95 19 4e 03 93 99 c3 82 4d 24 c5 1f 22 b2 6b de"
+ "10 24 cd 39 59 58 a2 df eb 48 16 a6 e8 ad ed b5"
+ "0b 1f 6b 56 d0 b3 06 0f f0 f1 c4 cb 0d 0e 00 1d"
+ "d5 9d 73 be 12";
+
+char* signature_3 =
+ "30 4c 02 24 00 00 00 00 43 18 fc eb 3b a8 3a a8 a3 cf 41 b7"
+ "81 4a f9 01 e1 8b 6e 95 c1 3a 83 25 9e a5 2e 66"
+ "7c 98 25 d9 02 24 00 00 00 00 54 f3 7f 5a e9 36 9c a2 f0 51"
+ "e0 6e 78 48 60 a3 f9 8a d5 2c 37 5a 0a 29 c9 f7"
+ "ea 57 7e 88 46 12";
+
+
+char* good_dsa_signature_1 =
+ "30 0D 02 01 01 02 08 00 A5 55 5A 01 FF A5 01";
+p256_int good_dsa_signature_1_r = {
+ .a = {0x00000001U, 0x00000000U, 0x00000000U, 0x00000000U,
+ 0x00000000U, 0x00000000U, 0x00000000U, 0x00000000U}
+};
+p256_int good_dsa_signature_1_s = {
+ .a = {0x01FFA501U, 0x00A5555AU, 0x00000000U, 0x00000000U,
+ 0x00000000U, 0x00000000U, 0x00000000U, 0x00000000U}
+};
+
+
+char* bad_dsa_signature_1 =
+ "a0 06 02 01 01 02 01 01";
+
+char* bad_dsa_signature_2 =
+ "30 07 02 01 01 02 01 01";
+
+char* bad_dsa_signature_3 =
+ "30 06 82 01 01 02 01 01";
+
+char* bad_dsa_signature_4 =
+ "30 06 02 00 01 02 01 01";
+
+char* bad_dsa_signature_5 =
+ "30 06 02 01 01 82 01 01";
+
+char* bad_dsa_signature_6 =
+ "30 05 02 01 01 02 00";
+
+char* bad_dsa_signature_7 =
+ "30 06 02 01 01 02 00 01";
+
+unsigned char* parsehex(char* str, int* len) {
+ // result can't be longer than input
+ unsigned char* result = malloc(strlen(str));
+
+ unsigned char* p = result;
+ *len = 0;
+
+ while (*str) {
+ int b;
+
+ while (isspace(*str)) str++;
+
+ switch (*str) {
+ case '0': case '1': case '2': case '3': case '4':
+ case '5': case '6': case '7': case '8': case '9':
+ b = (*str - '0') << 4; break;
+ case 'a': case 'b': case 'c': case 'd': case 'e': case 'f':
+ b = (*str - 'a' + 10) << 4; break;
+ case 'A': case 'B': case 'C': case 'D': case 'E': case 'F':
+ b = (*str - 'A' + 10) << 4; break;
+ case '\0':
+ return result;
+ default:
+ return NULL;
+ }
+ str++;
+
+ while (isspace(*str)) str++;
+
+ switch (*str) {
+ case '0': case '1': case '2': case '3': case '4':
+ case '5': case '6': case '7': case '8': case '9':
+ b |= *str - '0'; break;
+ case 'a': case 'b': case 'c': case 'd': case 'e': case 'f':
+ b |= *str - 'a' + 10; break;
+ case 'A': case 'B': case 'C': case 'D': case 'E': case 'F':
+ b |= *str - 'A' + 10; break;
+ default:
+ return NULL;
+ }
+ str++;
+
+ *p++ = b;
+ ++*len;
+ }
+
+ return result;
+}
+
+int main(int arg, char** argv) {
+
+ unsigned char hash_buf[SHA256_DIGEST_SIZE];
+
+ unsigned char* message;
+ int mlen;
+ unsigned char* signature;
+ int slen;
+
+ p256_int hash;
+ p256_int r;
+ p256_int s;
+
+ int success = 1;
+
+#define CHECK_DSA_SIG(sig, good) do {\
+ message = parsehex(sig, &mlen); \
+ int result = dsa_sig_unpack(message, mlen, &r, &s); \
+ printf(#sig ": %s\n", result ? "good" : "bad"); \
+ success = success && !(good ^ result); \
+ free(message); \
+ } while(0)
+#define CHECK_GOOD_DSA_SIG(n) do {\
+ CHECK_DSA_SIG(good_dsa_signature_##n, 1); \
+ int result = !memcmp(P256_DIGITS(&good_dsa_signature_##n##_r), P256_DIGITS(&r), \
+ P256_NBYTES); \
+ success = success && result; \
+ printf(" R value %s\n", result ? "good" : "bad"); \
+ result = !memcmp(P256_DIGITS(&good_dsa_signature_##n##_s), P256_DIGITS(&s), \
+ P256_NBYTES); \
+ success = success && result; \
+ printf(" S value %s\n", result ? "good" : "bad"); \
+ } while (0)
+#define CHECK_BAD_DSA_SIG(n) \
+ CHECK_DSA_SIG(bad_dsa_signature_##n, 0)
+
+ CHECK_GOOD_DSA_SIG(1);
+
+ CHECK_BAD_DSA_SIG(1);
+ CHECK_BAD_DSA_SIG(2);
+ CHECK_BAD_DSA_SIG(3);
+ CHECK_BAD_DSA_SIG(4);
+ CHECK_BAD_DSA_SIG(5);
+ CHECK_BAD_DSA_SIG(6);
+ CHECK_BAD_DSA_SIG(7);
+
+
+#define TEST_MESSAGE(n) do {\
+ message = parsehex(message_##n, &mlen); \
+ SHA256_hash(message, mlen, hash_buf); \
+ p256_from_bin(hash_buf, &hash); \
+ signature = parsehex(signature_##n, &slen); \
+ int result = dsa_sig_unpack(signature, slen, &r, &s); \
+ if (result) { result = p256_ecdsa_verify(&key_x, &key_y, &hash, &r, &s); } \
+ printf("message %d: %s\n", n, result ? "verified" : "not verified"); \
+ success = success && result; \
+ free(signature); \
+ } while(0)
+
+ TEST_MESSAGE(1);
+ TEST_MESSAGE(2);
+ TEST_MESSAGE(3);
+
+ printf("\n%s\n\n", success ? "PASS" : "FAIL");
+
+ return !success;
+}