Mercurial > dropbear

comparison libtomcrypt/src/pk/asn1/der/bit/der_encode_bit_string.c @ 398:59c7938af2bd

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
merge of '1250b8af44b62d8f4fe0f8d9fc7e7a1cc34e7e1c' and '7f8670ac3bb975f40967f3979d09d2199b7e90c8'
author Matt Johnston <matt@ucc.asn.au>
date Sat, 03 Feb 2007 08:20:30 +0000
parents 0cbe8f6dbf9e
children f849a5ca2efc
comparison
equal deleted inserted replaced
396:e7c1a77d2921 398:59c7938af2bd
4 * algorithms in a highly modular and flexible manner. 4 * algorithms in a highly modular and flexible manner.
5 * 5 *
6 * The library is free for all purposes without any express 6 * The library is free for all purposes without any express
7 * guarantee it works. 7 * guarantee it works.
8 * 8 *
9 * Tom St Denis, [email protected], http://libtomcrypt.org 9 * Tom St Denis, [email protected], http://libtomcrypt.com
10 */ 10 */
11 #include "tomcrypt.h" 11 #include "tomcrypt.h"
12 12
13 /** 13 /**
14 @file der_encode_bit_string.c 14 @file der_encode_bit_string.c
27 @return CRYPT_OK if successful 27 @return CRYPT_OK if successful
28 */ 28 */
29 int der_encode_bit_string(const unsigned char *in, unsigned long inlen, 29 int der_encode_bit_string(const unsigned char *in, unsigned long inlen,
30 unsigned char *out, unsigned long *outlen) 30 unsigned char *out, unsigned long *outlen)
31 { 31 {
32 unsigned long len, x, y, buf; 32 unsigned long len, x, y;
33 unsigned char buf;
33 int err; 34 int err;
34 35
35 LTC_ARGCHK(in != NULL); 36 LTC_ARGCHK(in != NULL);
36 LTC_ARGCHK(out != NULL); 37 LTC_ARGCHK(out != NULL);
37 LTC_ARGCHK(outlen != NULL); 38 LTC_ARGCHK(outlen != NULL);
40 if ((err = der_length_bit_string(inlen, &len)) != CRYPT_OK) { 41 if ((err = der_length_bit_string(inlen, &len)) != CRYPT_OK) {
41 return err; 42 return err;
42 } 43 }
43 44
44 if (len > *outlen) { 45 if (len > *outlen) {
46 *outlen = len;
45 return CRYPT_BUFFER_OVERFLOW; 47 return CRYPT_BUFFER_OVERFLOW;
46 } 48 }
47 49
48 /* store header (include bit padding count in length) */ 50 /* store header (include bit padding count in length) */
49 x = 0; 51 x = 0;
50 y = (inlen >> 3) + ((inlen&7) ? 1 : 0) + 1; 52 y = (inlen >> 3) + ((inlen&7) ? 1 : 0) + 1;
51 53
52 out[x++] = 0x03; 54 out[x++] = 0x03;
53 if (y < 128) { 55 if (y < 128) {
54 out[x++] = y; 56 out[x++] = (unsigned char)y;
55 } else if (y < 256) { 57 } else if (y < 256) {
56 out[x++] = 0x81; 58 out[x++] = 0x81;
57 out[x++] = y; 59 out[x++] = (unsigned char)y;
58 } else if (y < 65536) { 60 } else if (y < 65536) {
59 out[x++] = 0x82; 61 out[x++] = 0x82;
60 out[x++] = (y>>8)&255; 62 out[x++] = (unsigned char)((y>>8)&255);
61 out[x++] = y&255; 63 out[x++] = (unsigned char)(y&255);
62 } 64 }
63 65
64 /* store number of zero padding bits */ 66 /* store number of zero padding bits */
65 out[x++] = (8 - inlen) & 7; 67 out[x++] = (unsigned char)((8 - inlen) & 7);
66 68
67 /* store the bits in big endian format */ 69 /* store the bits in big endian format */
68 for (y = buf = 0; y < inlen; y++) { 70 for (y = buf = 0; y < inlen; y++) {
69 buf |= (in[y] ? 1 : 0) << (7 - (y & 7)); 71 buf |= (in[y] ? 1 : 0) << (7 - (y & 7));
70 if ((y & 7) == 7) { 72 if ((y & 7) == 7) {
81 } 83 }
82 84
83 #endif 85 #endif
84 86
85 /* $Source: /cvs/libtom/libtomcrypt/src/pk/asn1/der/bit/der_encode_bit_string.c,v $ */ 87 /* $Source: /cvs/libtom/libtomcrypt/src/pk/asn1/der/bit/der_encode_bit_string.c,v $ */
86 /* $Revision: 1.1 $ */ 88 /* $Revision: 1.4 $ */
87 /* $Date: 2005/05/16 15:08:11 $ */ 89 /* $Date: 2006/12/04 21:34:03 $ */