annotate src/pk/asn1/der/octet/der_decode_octet_string.c @ 380:d5faf4814ddb libtomcrypt-orig libtomcrypt-1.16

Update to LibTomCrypt 1.16
author Matt Johnston <matt@ucc.asn.au>
date Thu, 11 Jan 2007 02:22:00 +0000
parents 59400faa4b44
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
280
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
1 /* LibTomCrypt, modular cryptographic library -- Tom St Denis
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
2 *
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
3 * LibTomCrypt is a library that provides various cryptographic
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
4 * algorithms in a highly modular and flexible manner.
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
5 *
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
6 * The library is free for all purposes without any express
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
7 * guarantee it works.
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
8 *
380
d5faf4814ddb Update to LibTomCrypt 1.16
Matt Johnston <matt@ucc.asn.au>
parents: 280
diff changeset
9 * Tom St Denis, [email protected], http://libtomcrypt.com
280
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
10 */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
11 #include "tomcrypt.h"
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
12
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
13 /**
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
14 @file der_decode_octet_string.c
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
15 ASN.1 DER, encode a OCTET STRING, Tom St Denis
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
16 */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
17
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
18
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
19 #ifdef LTC_DER
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
20
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
21 /**
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
22 Store a OCTET STRING
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
23 @param in The DER encoded OCTET STRING
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
24 @param inlen The size of the DER OCTET STRING
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
25 @param out [out] The array of octets stored (one per char)
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
26 @param outlen [in/out] The number of octets stored
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
27 @return CRYPT_OK if successful
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
28 */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
29 int der_decode_octet_string(const unsigned char *in, unsigned long inlen,
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
30 unsigned char *out, unsigned long *outlen)
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
31 {
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
32 unsigned long x, y, len;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
33
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
34 LTC_ARGCHK(in != NULL);
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
35 LTC_ARGCHK(out != NULL);
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
36 LTC_ARGCHK(outlen != NULL);
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
37
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
38 /* must have header at least */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
39 if (inlen < 2) {
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
40 return CRYPT_INVALID_PACKET;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
41 }
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
42
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
43 /* check for 0x04 */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
44 if ((in[0] & 0x1F) != 0x04) {
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
45 return CRYPT_INVALID_PACKET;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
46 }
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
47 x = 1;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
48
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
49 /* decode the length */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
50 if (in[x] & 0x80) {
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
51 /* valid # of bytes in length are 1,2,3 */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
52 y = in[x] & 0x7F;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
53 if ((y == 0) || (y > 3) || ((x + y) > inlen)) {
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
54 return CRYPT_INVALID_PACKET;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
55 }
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
56
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
57 /* read the length in */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
58 len = 0;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
59 ++x;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
60 while (y--) {
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
61 len = (len << 8) | in[x++];
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
62 }
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
63 } else {
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
64 len = in[x++] & 0x7F;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
65 }
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
66
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
67 /* is it too long? */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
68 if (len > *outlen) {
380
d5faf4814ddb Update to LibTomCrypt 1.16
Matt Johnston <matt@ucc.asn.au>
parents: 280
diff changeset
69 *outlen = len;
280
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
70 return CRYPT_BUFFER_OVERFLOW;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
71 }
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
72
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
73 if (len + x > inlen) {
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
74 return CRYPT_INVALID_PACKET;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
75 }
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
76
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
77 /* read the data */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
78 for (y = 0; y < len; y++) {
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
79 out[y] = in[x++];
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
80 }
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
81
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
82 *outlen = y;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
83
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
84 return CRYPT_OK;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
85 }
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
86
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
87 #endif
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
88
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
89 /* $Source: /cvs/libtom/libtomcrypt/src/pk/asn1/der/octet/der_decode_octet_string.c,v $ */
380
d5faf4814ddb Update to LibTomCrypt 1.16
Matt Johnston <matt@ucc.asn.au>
parents: 280
diff changeset
90 /* $Revision: 1.3 $ */
d5faf4814ddb Update to LibTomCrypt 1.16
Matt Johnston <matt@ucc.asn.au>
parents: 280
diff changeset
91 /* $Date: 2006/06/16 21:53:41 $ */