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Add an EVP demo for signatures using EC
Fixes openssl#14115 Reviewed-by: Shane Lontis <shane.lontis@oracle.com> Reviewed-by: Paul Dale <pauli@openssl.org> (Merged from openssl#15429)
1 parent 74613e8 commit 691c9cd

4 files changed

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‎demos/README.txt‎

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@@ -26,3 +26,6 @@ smime:
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pkcs12:
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pkread.c Print out a description of a PKCS12 file.
2828
pkwrite.c Add a password to an existing PKCS12 file.
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signature:
31+
EVP_Signature_demo.c Compute and verify a signature from multiple buffers

‎demos/signature/EVP_Signature_demo.c‎

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@@ -0,0 +1,235 @@
1+
/*-
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* Copyright 2021 The OpenSSL Project Authors. All Rights Reserved.
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*
4+
* Licensed under the Apache License 2.0 (the "License"). You may not use
5+
* this file except in compliance with the License. You can obtain a copy
6+
* in the file LICENSE in the source distribution or at
7+
* https://www.openssl.org/source/license.html
8+
*/
9+
10+
/*
11+
* An example that uses the EVP_MD*, EVP_DigestSign* and EVP_DigestVerify*
12+
* methods to calculate and verify a signature of two static buffers.
13+
*/
14+
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#include <string.h>
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#include <stdio.h>
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#include <openssl/err.h>
18+
#include <openssl/evp.h>
19+
#include <openssl/decoder.h>
20+
#include "EVP_Signature_demo.h"
21+
22+
/*
23+
* This demonstration will calculate and verify a signature of data using
24+
* the soliloquy from Hamlet scene 1 act 3
25+
*/
26+
27+
static const char *hamlet_1 =
28+
"To be, or not to be, that is the question,\n"
29+
"Whether tis nobler in the minde to suffer\n"
30+
"The slings and arrowes of outragious fortune,\n"
31+
"Or to take Armes again in a sea of troubles,\n"
32+
;
33+
static const char *hamlet_2 =
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"And by opposing, end them, to die to sleep;\n"
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"No more, and by a sleep, to say we end\n"
36+
"The heart-ache, and the thousand natural shocks\n"
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"That flesh is heir to? tis a consumation\n"
38+
;
39+
40+
/*
41+
* For demo_sign, load EC private key priv_key from priv_key_der[].
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* For demo_verify, load EC public key pub_key from pub_key_der[].
43+
*/
44+
static EVP_PKEY *get_key(OSSL_LIB_CTX *libctx, const char *propq, int public)
45+
{
46+
OSSL_DECODER_CTX *dctx = NULL;
47+
EVP_PKEY *pkey = NULL;
48+
int selection;
49+
const unsigned char *data;
50+
size_t data_len;
51+
52+
if (public) {
53+
selection = EVP_PKEY_PUBLIC_KEY;
54+
data = pub_key_der;
55+
data_len = sizeof(pub_key_der);
56+
} else {
57+
selection = EVP_PKEY_KEYPAIR;
58+
data = priv_key_der;
59+
data_len = sizeof(priv_key_der);
60+
}
61+
dctx = OSSL_DECODER_CTX_new_for_pkey(&pkey, "DER", NULL, "EC",
62+
selection, libctx, propq);
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(void)OSSL_DECODER_from_data(dctx, &data, &data_len);
64+
OSSL_DECODER_CTX_free(dctx);
65+
if (pkey == NULL)
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fprintf(stderr, "Failed to load %s key.\n", public ? "public" : "private");
67+
return pkey;
68+
}
69+
70+
static int demo_sign(OSSL_LIB_CTX *libctx, const char *sig_name,
71+
size_t *sig_out_len, unsigned char **sig_out_value)
72+
{
73+
int result = 0, public = 0;
74+
size_t sig_len;
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unsigned char *sig_value = NULL;
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const char *propq = NULL;
77+
EVP_MD_CTX *sign_context = NULL;
78+
EVP_PKEY *priv_key = NULL;
79+
80+
/* Get private key */
81+
priv_key = get_key(libctx, propq, public);
82+
if (priv_key == NULL) {
83+
fprintf(stderr, "Get private key failed.\n");
84+
goto cleanup;
85+
}
86+
/*
87+
* Make a message signature context to hold temporary state
88+
* during signature creation
89+
*/
90+
sign_context = EVP_MD_CTX_new();
91+
if (sign_context == NULL) {
92+
fprintf(stderr, "EVP_MD_CTX_new failed.\n");
93+
goto cleanup;
94+
}
95+
/*
96+
* Initialize the sign context to use the fetched
97+
* sign provider.
98+
*/
99+
if (!EVP_DigestSignInit_ex(sign_context, NULL, sig_name,
100+
libctx, NULL, priv_key, NULL)) {
101+
fprintf(stderr, "EVP_DigestSignInit_ex failed.\n");
102+
goto cleanup;
103+
}
104+
/*
105+
* EVP_DigestSignUpdate() can be called several times on the same context
106+
* to include additional data.
107+
*/
108+
if (!EVP_DigestSignUpdate(sign_context, hamlet_1, strlen(hamlet_1))) {
109+
fprintf(stderr, "EVP_DigestSignUpdate(hamlet_1) failed.\n");
110+
goto cleanup;
111+
}
112+
if (!EVP_DigestSignUpdate(sign_context, hamlet_2, strlen(hamlet_2))) {
113+
fprintf(stderr, "EVP_DigestSignUpdate(hamlet_2) failed.\n");
114+
goto cleanup;
115+
}
116+
/* Call EVP_DigestSignFinal to get signature length sig_len */
117+
if (!EVP_DigestSignFinal(sign_context, NULL, &sig_len)) {
118+
fprintf(stderr, "EVP_DigestSignFinal failed.\n");
119+
goto cleanup;
120+
}
121+
if (sig_len <= 0) {
122+
fprintf(stderr, "EVP_DigestSignFinal returned invalid signature length.\n");
123+
goto cleanup;
124+
}
125+
sig_value = OPENSSL_malloc(sig_len);
126+
if (sig_value == NULL) {
127+
fprintf(stderr, "No memory.\n");
128+
goto cleanup;
129+
}
130+
if (!EVP_DigestSignFinal(sign_context, sig_value, &sig_len)) {
131+
fprintf(stderr, "EVP_DigestSignFinal failed.\n");
132+
goto cleanup;
133+
}
134+
*sig_out_len = sig_len;
135+
*sig_out_value = sig_value;
136+
fprintf(stdout, "Generating signature:\n");
137+
BIO_dump_indent_fp(stdout, sig_value, sig_len, 2);
138+
fprintf(stdout, "\n");
139+
result = 1;
140+
141+
cleanup:
142+
/* OpenSSL free functions will ignore NULL arguments */
143+
if (!result)
144+
OPENSSL_free(sig_value);
145+
EVP_PKEY_free(priv_key);
146+
EVP_MD_CTX_free(sign_context);
147+
return result;
148+
}
149+
150+
static int demo_verify(OSSL_LIB_CTX *libctx, const char *sig_name,
151+
size_t sig_len, unsigned char *sig_value)
152+
{
153+
int result = 0, public = 1;
154+
const char *propq = NULL;
155+
EVP_MD_CTX *verify_context = NULL;
156+
EVP_PKEY *pub_key = NULL;
157+
158+
/*
159+
* Make a verify signature context to hold temporary state
160+
* during signature verification
161+
*/
162+
verify_context = EVP_MD_CTX_new();
163+
if (verify_context == NULL) {
164+
fprintf(stderr, "EVP_MD_CTX_new failed.\n");
165+
goto cleanup;
166+
}
167+
/* Get public key */
168+
pub_key = get_key(libctx, propq, public);
169+
if (pub_key == NULL) {
170+
fprintf(stderr, "Get public key failed.\n");
171+
goto cleanup;
172+
}
173+
/* Verify */
174+
if (!EVP_DigestVerifyInit_ex(verify_context, NULL, sig_name,
175+
libctx, NULL, pub_key, NULL)) {
176+
fprintf(stderr, "EVP_DigestVerifyInit failed.\n");
177+
goto cleanup;
178+
}
179+
/*
180+
* EVP_DigestVerifyUpdate() can be called several times on the same context
181+
* to include additional data.
182+
*/
183+
if (!EVP_DigestVerifyUpdate(verify_context, hamlet_1, strlen(hamlet_1))) {
184+
fprintf(stderr, "EVP_DigestVerifyUpdate(hamlet_1) failed.\n");
185+
goto cleanup;
186+
}
187+
if (!EVP_DigestVerifyUpdate(verify_context, hamlet_2, strlen(hamlet_2))) {
188+
fprintf(stderr, "EVP_DigestVerifyUpdate(hamlet_2) failed.\n");
189+
goto cleanup;
190+
}
191+
if (!EVP_DigestVerifyFinal(verify_context, sig_value, sig_len)) {
192+
fprintf(stderr, "EVP_DigestVerifyFinal failed.\n");
193+
goto cleanup;
194+
}
195+
fprintf(stdout, "Signature verified.\n");
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result = 1;
197+
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cleanup:
199+
/* OpenSSL free functions will ignore NULL arguments */
200+
EVP_PKEY_free(pub_key);
201+
EVP_MD_CTX_free(verify_context);
202+
return result;
203+
}
204+
205+
int main(void)
206+
{
207+
OSSL_LIB_CTX *libctx = NULL;
208+
const char *sig_name = "SHA3-512";
209+
size_t sig_len = 0;
210+
unsigned char *sig_value = NULL;
211+
int result = 0;
212+
213+
libctx = OSSL_LIB_CTX_new();
214+
if (libctx == NULL) {
215+
fprintf(stderr, "OSSL_LIB_CTX_new() returned NULL\n");
216+
goto cleanup;
217+
}
218+
if (!demo_sign(libctx, sig_name, &sig_len, &sig_value)) {
219+
fprintf(stderr, "demo_sign failed.\n");
220+
goto cleanup;
221+
}
222+
if (!demo_verify(libctx, sig_name, sig_len, sig_value)) {
223+
fprintf(stderr, "demo_verify failed.\n");
224+
goto cleanup;
225+
}
226+
result = 1;
227+
228+
cleanup:
229+
if (result != 1)
230+
ERR_print_errors_fp(stderr);
231+
/* OpenSSL free functions will ignore NULL arguments */
232+
OSSL_LIB_CTX_free(libctx);
233+
OPENSSL_free(sig_value);
234+
return result == 0;
235+
}

‎demos/signature/EVP_Signature_demo.h‎

Lines changed: 76 additions & 0 deletions
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1+
/*-
2+
* Copyright 2021 The OpenSSL Project Authors. All Rights Reserved.
3+
*
4+
* Licensed under the Apache License 2.0 (the "License"). You may not use
5+
* this file except in compliance with the License. You can obtain a copy
6+
* in the file LICENSE in the source distribution or at
7+
* https://www.openssl.org/source/license.html
8+
*/
9+
10+
/* Signers private EC key */
11+
static const unsigned char priv_key_der[] = {
12+
0x30, 0x82, 0x01, 0x68, 0x02, 0x01, 0x01, 0x04, 0x20, 0x51, 0x77, 0xae,
13+
0xf4, 0x18, 0xf4, 0x6b, 0xc4, 0xe5, 0xbb, 0xe9, 0xe6, 0x9e, 0x6d, 0xb0,
14+
0xea, 0x12, 0xf9, 0xf3, 0xdb, 0x9d, 0x56, 0x59, 0xf7, 0x5a, 0x17, 0xd7,
15+
0xd1, 0xe4, 0xd7, 0x47, 0x28, 0xa0, 0x81, 0xfa, 0x30, 0x81, 0xf7, 0x02,
16+
0x01, 0x01, 0x30, 0x2c, 0x06, 0x07, 0x2a, 0x86, 0x48, 0xce, 0x3d, 0x01,
17+
0x01, 0x02, 0x21, 0x00, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x01,
18+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
19+
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
20+
0x30, 0x5b, 0x04, 0x20, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x01,
21+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
22+
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfc,
23+
0x04, 0x20, 0x5a, 0xc6, 0x35, 0xd8, 0xaa, 0x3a, 0x93, 0xe7, 0xb3, 0xeb,
24+
0xbd, 0x55, 0x76, 0x98, 0x86, 0xbc, 0x65, 0x1d, 0x06, 0xb0, 0xcc, 0x53,
25+
0xb0, 0xf6, 0x3b, 0xce, 0x3c, 0x3e, 0x27, 0xd2, 0x60, 0x4b, 0x03, 0x15,
26+
0x00, 0xc4, 0x9d, 0x36, 0x08, 0x86, 0xe7, 0x04, 0x93, 0x6a, 0x66, 0x78,
27+
0xe1, 0x13, 0x9d, 0x26, 0xb7, 0x81, 0x9f, 0x7e, 0x90, 0x04, 0x41, 0x04,
28+
0x6b, 0x17, 0xd1, 0xf2, 0xe1, 0x2c, 0x42, 0x47, 0xf8, 0xbc, 0xe6, 0xe5,
29+
0x63, 0xa4, 0x40, 0xf2, 0x77, 0x03, 0x7d, 0x81, 0x2d, 0xeb, 0x33, 0xa0,
30+
0xf4, 0xa1, 0x39, 0x45, 0xd8, 0x98, 0xc2, 0x96, 0x4f, 0xe3, 0x42, 0xe2,
31+
0xfe, 0x1a, 0x7f, 0x9b, 0x8e, 0xe7, 0xeb, 0x4a, 0x7c, 0x0f, 0x9e, 0x16,
32+
0x2b, 0xce, 0x33, 0x57, 0x6b, 0x31, 0x5e, 0xce, 0xcb, 0xb6, 0x40, 0x68,
33+
0x37, 0xbf, 0x51, 0xf5, 0x02, 0x21, 0x00, 0xff, 0xff, 0xff, 0xff, 0x00,
34+
0x00, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xbc,
35+
0xe6, 0xfa, 0xad, 0xa7, 0x17, 0x9e, 0x84, 0xf3, 0xb9, 0xca, 0xc2, 0xfc,
36+
0x63, 0x25, 0x51, 0x02, 0x01, 0x01, 0xa1, 0x44, 0x03, 0x42, 0x00, 0x04,
37+
0x4f, 0xe7, 0x7b, 0xb6, 0xbb, 0x54, 0x42, 0x39, 0xed, 0x5d, 0xe5, 0x40,
38+
0xc8, 0xd8, 0x71, 0xca, 0x6d, 0x83, 0x71, 0xd1, 0x88, 0x2a, 0x65, 0x00,
39+
0x6c, 0xc6, 0x2f, 0x01, 0x31, 0x49, 0xbe, 0x76, 0x7a, 0x67, 0x6a, 0x28,
40+
0x33, 0xc7, 0x5b, 0xb9, 0x24, 0x45, 0x24, 0x6e, 0xf0, 0x6d, 0x2f, 0x34,
41+
0x06, 0x53, 0x73, 0x6a, 0xff, 0x90, 0x90, 0xc1, 0x6d, 0x9b, 0x94, 0x0d,
42+
0x0e, 0x1f, 0x95, 0x65,
43+
};
44+
45+
/* The matching public key used for verifying */
46+
static const unsigned char pub_key_der[] = {
47+
0x30, 0x82, 0x01, 0x4b, 0x30, 0x82, 0x01, 0x03, 0x06, 0x07, 0x2a, 0x86,
48+
0x48, 0xce, 0x3d, 0x02, 0x01, 0x30, 0x81, 0xf7, 0x02, 0x01, 0x01, 0x30,
49+
0x2c, 0x06, 0x07, 0x2a, 0x86, 0x48, 0xce, 0x3d, 0x01, 0x01, 0x02, 0x21,
50+
0x00, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00,
51+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff,
52+
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x30, 0x5b, 0x04,
53+
0x20, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00,
54+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff,
55+
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfc, 0x04, 0x20, 0x5a,
56+
0xc6, 0x35, 0xd8, 0xaa, 0x3a, 0x93, 0xe7, 0xb3, 0xeb, 0xbd, 0x55, 0x76,
57+
0x98, 0x86, 0xbc, 0x65, 0x1d, 0x06, 0xb0, 0xcc, 0x53, 0xb0, 0xf6, 0x3b,
58+
0xce, 0x3c, 0x3e, 0x27, 0xd2, 0x60, 0x4b, 0x03, 0x15, 0x00, 0xc4, 0x9d,
59+
0x36, 0x08, 0x86, 0xe7, 0x04, 0x93, 0x6a, 0x66, 0x78, 0xe1, 0x13, 0x9d,
60+
0x26, 0xb7, 0x81, 0x9f, 0x7e, 0x90, 0x04, 0x41, 0x04, 0x6b, 0x17, 0xd1,
61+
0xf2, 0xe1, 0x2c, 0x42, 0x47, 0xf8, 0xbc, 0xe6, 0xe5, 0x63, 0xa4, 0x40,
62+
0xf2, 0x77, 0x03, 0x7d, 0x81, 0x2d, 0xeb, 0x33, 0xa0, 0xf4, 0xa1, 0x39,
63+
0x45, 0xd8, 0x98, 0xc2, 0x96, 0x4f, 0xe3, 0x42, 0xe2, 0xfe, 0x1a, 0x7f,
64+
0x9b, 0x8e, 0xe7, 0xeb, 0x4a, 0x7c, 0x0f, 0x9e, 0x16, 0x2b, 0xce, 0x33,
65+
0x57, 0x6b, 0x31, 0x5e, 0xce, 0xcb, 0xb6, 0x40, 0x68, 0x37, 0xbf, 0x51,
66+
0xf5, 0x02, 0x21, 0x00, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00,
67+
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xbc, 0xe6, 0xfa, 0xad,
68+
0xa7, 0x17, 0x9e, 0x84, 0xf3, 0xb9, 0xca, 0xc2, 0xfc, 0x63, 0x25, 0x51,
69+
0x02, 0x01, 0x01, 0x03, 0x42, 0x00, 0x04, 0x4f, 0xe7, 0x7b, 0xb6, 0xbb,
70+
0x54, 0x42, 0x39, 0xed, 0x5d, 0xe5, 0x40, 0xc8, 0xd8, 0x71, 0xca, 0x6d,
71+
0x83, 0x71, 0xd1, 0x88, 0x2a, 0x65, 0x00, 0x6c, 0xc6, 0x2f, 0x01, 0x31,
72+
0x49, 0xbe, 0x76, 0x7a, 0x67, 0x6a, 0x28, 0x33, 0xc7, 0x5b, 0xb9, 0x24,
73+
0x45, 0x24, 0x6e, 0xf0, 0x6d, 0x2f, 0x34, 0x06, 0x53, 0x73, 0x6a, 0xff,
74+
0x90, 0x90, 0xc1, 0x6d, 0x9b, 0x94, 0x0d, 0x0e, 0x1f, 0x95, 0x65,
75+
};
76+

‎demos/signature/Makefile‎

Lines changed: 20 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,20 @@
1+
#
2+
# To run the demos when linked with a shared library (default):
3+
#
4+
# LD_LIBRARY_PATH=../.. ./EVP_Signature_demo
5+
6+
CFLAGS = -I../../include -g
7+
LDFLAGS = -L../..
8+
LDLIBS = -lcrypto
9+
10+
all: EVP_Signature_demo
11+
12+
%.o: %.c
13+
$(CC) $(CFLAGS) -c $<
14+
15+
EVP_Signature_demo: EVP_Signature_demo.o
16+
17+
test: ;
18+
19+
clean:
20+
$(RM) *.o EVP_Signature_demo

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