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authorMatt Johnston <matt@ucc.asn.au>2006-03-08 13:23:58 +0000
committerMatt Johnston <matt@ucc.asn.au>2006-03-08 13:23:58 +0000
commit6ae3a09ef33b62811a7f60a1f97dcb89907c1ac1 (patch)
tree37e84722c5b30bbfc86947bee260473d4604b616 /libtomcrypt/src/pk/asn1/der/bit
parent33defd1f9b6c4889fe5b075e6abb0b24c00f3a59 (diff)
parent8608a8e64c1aeda096867f43f89e29e1aee207ae (diff)
propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 20dccfc09627970a312d77fb41dc2970b62689c3)
to branch 'au.asn.ucc.matt.dropbear' (head fdf4a7a3b97ae5046139915de7e40399cceb2c01) --HG-- extra : convert_revision : dc4809882e1b9f2dcd3f8bbe38c74a0a52c39ce4
Diffstat (limited to 'libtomcrypt/src/pk/asn1/der/bit')
-rw-r--r--libtomcrypt/src/pk/asn1/der/bit/der_decode_bit_string.c101
-rw-r--r--libtomcrypt/src/pk/asn1/der/bit/der_encode_bit_string.c87
-rw-r--r--libtomcrypt/src/pk/asn1/der/bit/der_length_bit_string.c54
3 files changed, 242 insertions, 0 deletions
diff --git a/libtomcrypt/src/pk/asn1/der/bit/der_decode_bit_string.c b/libtomcrypt/src/pk/asn1/der/bit/der_decode_bit_string.c
new file mode 100644
index 0000000..da5b989
--- /dev/null
+++ b/libtomcrypt/src/pk/asn1/der/bit/der_decode_bit_string.c
@@ -0,0 +1,101 @@
+/* LibTomCrypt, modular cryptographic library -- Tom St Denis
+ *
+ * LibTomCrypt is a library that provides various cryptographic
+ * algorithms in a highly modular and flexible manner.
+ *
+ * The library is free for all purposes without any express
+ * guarantee it works.
+ *
+ * Tom St Denis, tomstdenis@gmail.com, http://libtomcrypt.org
+ */
+#include "tomcrypt.h"
+
+/**
+ @file der_decode_bit_string.c
+ ASN.1 DER, encode a BIT STRING, Tom St Denis
+*/
+
+
+#ifdef LTC_DER
+
+/**
+ Store a BIT STRING
+ @param in The DER encoded BIT STRING
+ @param inlen The size of the DER BIT STRING
+ @param out [out] The array of bits stored (one per char)
+ @param outlen [in/out] The number of bits stored
+ @return CRYPT_OK if successful
+*/
+int der_decode_bit_string(const unsigned char *in, unsigned long inlen,
+ unsigned char *out, unsigned long *outlen)
+{
+ unsigned long dlen, blen, x, y;
+
+ LTC_ARGCHK(in != NULL);
+ LTC_ARGCHK(out != NULL);
+ LTC_ARGCHK(outlen != NULL);
+
+ /* packet must be at least 4 bytes */
+ if (inlen < 4) {
+ return CRYPT_INVALID_ARG;
+ }
+
+ /* check for 0x03 */
+ if ((in[0]&0x1F) != 0x03) {
+ return CRYPT_INVALID_PACKET;
+ }
+
+ /* offset in the data */
+ x = 1;
+
+ /* get the length of the data */
+ if (in[x] & 0x80) {
+ /* long format get number of length bytes */
+ y = in[x++] & 127;
+
+ /* invalid if 0 or > 2 */
+ if (y == 0 || y > 2) {
+ return CRYPT_INVALID_PACKET;
+ }
+
+ /* read the data len */
+ dlen = 0;
+ while (y--) {
+ dlen = (dlen << 8) | (unsigned long)in[x++];
+ }
+ } else {
+ /* short format */
+ dlen = in[x++] & 127;
+ }
+
+ /* is the data len too long or too short? */
+ if ((dlen == 0) || (dlen + x > inlen)) {
+ return CRYPT_INVALID_PACKET;
+ }
+
+ /* get padding count */
+ blen = ((dlen - 1) << 3) - (in[x++] & 7);
+
+ /* too many bits? */
+ if (blen > *outlen) {
+ return CRYPT_BUFFER_OVERFLOW;
+ }
+
+ /* decode/store the bits */
+ for (y = 0; y < blen; y++) {
+ out[y] = (in[x] & (1 << (7 - (y & 7)))) ? 1 : 0;
+ if ((y & 7) == 7) {
+ ++x;
+ }
+ }
+
+ /* we done */
+ *outlen = blen;
+ return CRYPT_OK;
+}
+
+#endif
+
+/* $Source: /cvs/libtom/libtomcrypt/src/pk/asn1/der/bit/der_decode_bit_string.c,v $ */
+/* $Revision: 1.1 $ */
+/* $Date: 2005/05/16 15:08:11 $ */
diff --git a/libtomcrypt/src/pk/asn1/der/bit/der_encode_bit_string.c b/libtomcrypt/src/pk/asn1/der/bit/der_encode_bit_string.c
new file mode 100644
index 0000000..569c15b
--- /dev/null
+++ b/libtomcrypt/src/pk/asn1/der/bit/der_encode_bit_string.c
@@ -0,0 +1,87 @@
+/* LibTomCrypt, modular cryptographic library -- Tom St Denis
+ *
+ * LibTomCrypt is a library that provides various cryptographic
+ * algorithms in a highly modular and flexible manner.
+ *
+ * The library is free for all purposes without any express
+ * guarantee it works.
+ *
+ * Tom St Denis, tomstdenis@gmail.com, http://libtomcrypt.org
+ */
+#include "tomcrypt.h"
+
+/**
+ @file der_encode_bit_string.c
+ ASN.1 DER, encode a BIT STRING, Tom St Denis
+*/
+
+
+#ifdef LTC_DER
+
+/**
+ Store a BIT STRING
+ @param in The array of bits to store (one per char)
+ @param inlen The number of bits tostore
+ @param out [out] The destination for the DER encoded BIT STRING
+ @param outlen [in/out] The max size and resulting size of the DER BIT STRING
+ @return CRYPT_OK if successful
+*/
+int der_encode_bit_string(const unsigned char *in, unsigned long inlen,
+ unsigned char *out, unsigned long *outlen)
+{
+ unsigned long len, x, y, buf;
+ int err;
+
+ LTC_ARGCHK(in != NULL);
+ LTC_ARGCHK(out != NULL);
+ LTC_ARGCHK(outlen != NULL);
+
+ /* avoid overflows */
+ if ((err = der_length_bit_string(inlen, &len)) != CRYPT_OK) {
+ return err;
+ }
+
+ if (len > *outlen) {
+ return CRYPT_BUFFER_OVERFLOW;
+ }
+
+ /* store header (include bit padding count in length) */
+ x = 0;
+ y = (inlen >> 3) + ((inlen&7) ? 1 : 0) + 1;
+
+ out[x++] = 0x03;
+ if (y < 128) {
+ out[x++] = y;
+ } else if (y < 256) {
+ out[x++] = 0x81;
+ out[x++] = y;
+ } else if (y < 65536) {
+ out[x++] = 0x82;
+ out[x++] = (y>>8)&255;
+ out[x++] = y&255;
+ }
+
+ /* store number of zero padding bits */
+ out[x++] = (8 - inlen) & 7;
+
+ /* store the bits in big endian format */
+ for (y = buf = 0; y < inlen; y++) {
+ buf |= (in[y] ? 1 : 0) << (7 - (y & 7));
+ if ((y & 7) == 7) {
+ out[x++] = buf;
+ buf = 0;
+ }
+ }
+ /* store last byte */
+ if (inlen & 7) {
+ out[x++] = buf;
+ }
+ *outlen = x;
+ return CRYPT_OK;
+}
+
+#endif
+
+/* $Source: /cvs/libtom/libtomcrypt/src/pk/asn1/der/bit/der_encode_bit_string.c,v $ */
+/* $Revision: 1.1 $ */
+/* $Date: 2005/05/16 15:08:11 $ */
diff --git a/libtomcrypt/src/pk/asn1/der/bit/der_length_bit_string.c b/libtomcrypt/src/pk/asn1/der/bit/der_length_bit_string.c
new file mode 100644
index 0000000..dd6ea6d
--- /dev/null
+++ b/libtomcrypt/src/pk/asn1/der/bit/der_length_bit_string.c
@@ -0,0 +1,54 @@
+/* LibTomCrypt, modular cryptographic library -- Tom St Denis
+ *
+ * LibTomCrypt is a library that provides various cryptographic
+ * algorithms in a highly modular and flexible manner.
+ *
+ * The library is free for all purposes without any express
+ * guarantee it works.
+ *
+ * Tom St Denis, tomstdenis@gmail.com, http://libtomcrypt.org
+ */
+#include "tomcrypt.h"
+
+/**
+ @file der_length_bit_string.c
+ ASN.1 DER, get length of BIT STRING, Tom St Denis
+*/
+
+#ifdef LTC_DER
+/**
+ Gets length of DER encoding of BIT STRING
+ @param nbits The number of bits in the string to encode
+ @param outlen [out] The length of the DER encoding for the given string
+ @return CRYPT_OK if successful
+*/
+int der_length_bit_string(unsigned long nbits, unsigned long *outlen)
+{
+ unsigned long nbytes;
+ LTC_ARGCHK(outlen != NULL);
+
+ /* get the number of the bytes */
+ nbytes = (nbits >> 3) + ((nbits & 7) ? 1 : 0) + 1;
+
+ if (nbytes < 128) {
+ /* 03 LL PP DD DD DD ... */
+ *outlen = 2 + nbytes;
+ } else if (nbytes < 256) {
+ /* 03 81 LL PP DD DD DD ... */
+ *outlen = 3 + nbytes;
+ } else if (nbytes < 65536) {
+ /* 03 82 LL LL PP DD DD DD ... */
+ *outlen = 4 + nbytes;
+ } else {
+ return CRYPT_INVALID_ARG;
+ }
+
+ return CRYPT_OK;
+}
+
+#endif
+
+
+/* $Source: /cvs/libtom/libtomcrypt/src/pk/asn1/der/bit/der_length_bit_string.c,v $ */
+/* $Revision: 1.1 $ */
+/* $Date: 2005/05/16 15:08:11 $ */