lax_der_privatekey_parsing.c (5210B)
1 /*********************************************************************** 2 * Copyright (c) 2014, 2015 Pieter Wuille * 3 * Distributed under the MIT software license, see the accompanying * 4 * file COPYING or https://www.opensource.org/licenses/mit-license.php.* 5 ***********************************************************************/ 6 7 #include <string.h> 8 9 #include "lax_der_privatekey_parsing.h" 10 11 int ec_privkey_import_der(const haskellsecp256k1_v0_1_0_context* ctx, unsigned char *out32, const unsigned char *privkey, size_t privkeylen) { 12 const unsigned char *end = privkey + privkeylen; 13 int lenb = 0; 14 int len = 0; 15 memset(out32, 0, 32); 16 /* sequence header */ 17 if (end < privkey+1 || *privkey != 0x30) { 18 return 0; 19 } 20 privkey++; 21 /* sequence length constructor */ 22 if (end < privkey+1 || !(*privkey & 0x80)) { 23 return 0; 24 } 25 lenb = *privkey & ~0x80; privkey++; 26 if (lenb < 1 || lenb > 2) { 27 return 0; 28 } 29 if (end < privkey+lenb) { 30 return 0; 31 } 32 /* sequence length */ 33 len = privkey[lenb-1] | (lenb > 1 ? privkey[lenb-2] << 8 : 0); 34 privkey += lenb; 35 if (end < privkey+len) { 36 return 0; 37 } 38 /* sequence element 0: version number (=1) */ 39 if (end < privkey+3 || privkey[0] != 0x02 || privkey[1] != 0x01 || privkey[2] != 0x01) { 40 return 0; 41 } 42 privkey += 3; 43 /* sequence element 1: octet string, up to 32 bytes */ 44 if (end < privkey+2 || privkey[0] != 0x04 || privkey[1] > 0x20 || end < privkey+2+privkey[1]) { 45 return 0; 46 } 47 if (privkey[1]) memcpy(out32 + 32 - privkey[1], privkey + 2, privkey[1]); 48 if (!haskellsecp256k1_v0_1_0_ec_seckey_verify(ctx, out32)) { 49 memset(out32, 0, 32); 50 return 0; 51 } 52 return 1; 53 } 54 55 int ec_privkey_export_der(const haskellsecp256k1_v0_1_0_context *ctx, unsigned char *privkey, size_t *privkeylen, const unsigned char *key32, int compressed) { 56 haskellsecp256k1_v0_1_0_pubkey pubkey; 57 size_t pubkeylen = 0; 58 if (!haskellsecp256k1_v0_1_0_ec_pubkey_create(ctx, &pubkey, key32)) { 59 *privkeylen = 0; 60 return 0; 61 } 62 if (compressed) { 63 static const unsigned char begin[] = { 64 0x30,0x81,0xD3,0x02,0x01,0x01,0x04,0x20 65 }; 66 static const unsigned char middle[] = { 67 0xA0,0x81,0x85,0x30,0x81,0x82,0x02,0x01,0x01,0x30,0x2C,0x06,0x07,0x2A,0x86,0x48, 68 0xCE,0x3D,0x01,0x01,0x02,0x21,0x00,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, 69 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, 70 0xFF,0xFF,0xFE,0xFF,0xFF,0xFC,0x2F,0x30,0x06,0x04,0x01,0x00,0x04,0x01,0x07,0x04, 71 0x21,0x02,0x79,0xBE,0x66,0x7E,0xF9,0xDC,0xBB,0xAC,0x55,0xA0,0x62,0x95,0xCE,0x87, 72 0x0B,0x07,0x02,0x9B,0xFC,0xDB,0x2D,0xCE,0x28,0xD9,0x59,0xF2,0x81,0x5B,0x16,0xF8, 73 0x17,0x98,0x02,0x21,0x00,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, 74 0xFF,0xFF,0xFF,0xFF,0xFE,0xBA,0xAE,0xDC,0xE6,0xAF,0x48,0xA0,0x3B,0xBF,0xD2,0x5E, 75 0x8C,0xD0,0x36,0x41,0x41,0x02,0x01,0x01,0xA1,0x24,0x03,0x22,0x00 76 }; 77 unsigned char *ptr = privkey; 78 memcpy(ptr, begin, sizeof(begin)); ptr += sizeof(begin); 79 memcpy(ptr, key32, 32); ptr += 32; 80 memcpy(ptr, middle, sizeof(middle)); ptr += sizeof(middle); 81 pubkeylen = 33; 82 haskellsecp256k1_v0_1_0_ec_pubkey_serialize(ctx, ptr, &pubkeylen, &pubkey, SECP256K1_EC_COMPRESSED); 83 ptr += pubkeylen; 84 *privkeylen = ptr - privkey; 85 } else { 86 static const unsigned char begin[] = { 87 0x30,0x82,0x01,0x13,0x02,0x01,0x01,0x04,0x20 88 }; 89 static const unsigned char middle[] = { 90 0xA0,0x81,0xA5,0x30,0x81,0xA2,0x02,0x01,0x01,0x30,0x2C,0x06,0x07,0x2A,0x86,0x48, 91 0xCE,0x3D,0x01,0x01,0x02,0x21,0x00,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, 92 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, 93 0xFF,0xFF,0xFE,0xFF,0xFF,0xFC,0x2F,0x30,0x06,0x04,0x01,0x00,0x04,0x01,0x07,0x04, 94 0x41,0x04,0x79,0xBE,0x66,0x7E,0xF9,0xDC,0xBB,0xAC,0x55,0xA0,0x62,0x95,0xCE,0x87, 95 0x0B,0x07,0x02,0x9B,0xFC,0xDB,0x2D,0xCE,0x28,0xD9,0x59,0xF2,0x81,0x5B,0x16,0xF8, 96 0x17,0x98,0x48,0x3A,0xDA,0x77,0x26,0xA3,0xC4,0x65,0x5D,0xA4,0xFB,0xFC,0x0E,0x11, 97 0x08,0xA8,0xFD,0x17,0xB4,0x48,0xA6,0x85,0x54,0x19,0x9C,0x47,0xD0,0x8F,0xFB,0x10, 98 0xD4,0xB8,0x02,0x21,0x00,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, 99 0xFF,0xFF,0xFF,0xFF,0xFE,0xBA,0xAE,0xDC,0xE6,0xAF,0x48,0xA0,0x3B,0xBF,0xD2,0x5E, 100 0x8C,0xD0,0x36,0x41,0x41,0x02,0x01,0x01,0xA1,0x44,0x03,0x42,0x00 101 }; 102 unsigned char *ptr = privkey; 103 memcpy(ptr, begin, sizeof(begin)); ptr += sizeof(begin); 104 memcpy(ptr, key32, 32); ptr += 32; 105 memcpy(ptr, middle, sizeof(middle)); ptr += sizeof(middle); 106 pubkeylen = 65; 107 haskellsecp256k1_v0_1_0_ec_pubkey_serialize(ctx, ptr, &pubkeylen, &pubkey, SECP256K1_EC_UNCOMPRESSED); 108 ptr += pubkeylen; 109 *privkeylen = ptr - privkey; 110 } 111 return 1; 112 }