Commit e1cc0671 authored by Dr. Stephen Henson's avatar Dr. Stephen Henson
Browse files

Use more efficient way to locate end of an ASN1 structure.

parent c1a8a5de

crypto/asn1/asn1.h

+1 −0
Original line number Diff line number Diff line
@@ -1035,6 +1035,7 @@ void ERR_load_ASN1_strings(void); 
#define ASN1_F_ASN1_DUP					 111

#define ASN1_F_ASN1_ENUMERATED_SET			 112

#define ASN1_F_ASN1_ENUMERATED_TO_BN			 113

#define ASN1_F_ASN1_FIND_END				 190

#define ASN1_F_ASN1_GENERALIZEDTIME_SET			 185

#define ASN1_F_ASN1_GENERATE_V3				 178

#define ASN1_F_ASN1_GET_OBJECT				 114

crypto/asn1/asn1_err.c

+1 −0
Original line number Diff line number Diff line
@@ -88,6 +88,7 @@ static ERR_STRING_DATA ASN1_str_functs[]= 
{ERR_FUNC(ASN1_F_ASN1_DUP),	"ASN1_dup"},

{ERR_FUNC(ASN1_F_ASN1_ENUMERATED_SET),	"ASN1_ENUMERATED_set"},

{ERR_FUNC(ASN1_F_ASN1_ENUMERATED_TO_BN),	"ASN1_ENUMERATED_to_BN"},

{ERR_FUNC(ASN1_F_ASN1_FIND_END),	"ASN1_FIND_END"},

{ERR_FUNC(ASN1_F_ASN1_GENERALIZEDTIME_SET),	"ASN1_GENERALIZEDTIME_set"},

{ERR_FUNC(ASN1_F_ASN1_GENERATE_V3),	"ASN1_generate_v3"},

{ERR_FUNC(ASN1_F_ASN1_GET_OBJECT),	"ASN1_get_object"},

crypto/asn1/tasn_dec.c

+59 −4
Original line number Diff line number Diff line
@@ -66,6 +66,7 @@ 
#include <openssl/err.h>



static int asn1_check_eoc(const unsigned char **in, long len);

static int asn1_find_end(const unsigned char **in, long len, char inf);



static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len,

				char inf, int tag, int aclass);
@@ -848,7 +849,7 @@ static int asn1_d2i_ex_primitive(ASN1_VALUE **pval, 
		/* If indefinite length constructed find the real end */

		if (inf)

			{

			if (!asn1_collect(NULL, &p, plen, inf, -1, -1))

			if (!asn1_find_end(&p, plen, inf))

				 goto err;

			len = p - cont;

			}
@@ -1053,12 +1054,66 @@ int asn1_ex_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len, 
	return ret;

	}





/* This function finds the end of an ASN1 structure when passed its maximum

 * length, whether it is indefinite length and a pointer to the content.

 * This is more efficient than calling asn1_collect because it does not

 * recurse on each indefinite length header.

 */



static int asn1_find_end(const unsigned char **in, long len, char inf)

	{

	int expected_eoc;

	long plen;

	const unsigned char *p = *in, *q;

	/* If not indefinite length constructed just add length */

	if (inf == 0)

		{

		*in += len;

		return 1;

		}

	expected_eoc = 1;

	/* Indefinite length constructed form. Find the end when enough EOCs

	 * are found. If more indefinite length constructed headers

	 * are encountered increment the expected eoc count otherwise just

	 * skip to the end of the data.

	 */

	while (len > 0)

		{

		if(asn1_check_eoc(&p, len))

			{

			expected_eoc--;

			if (expected_eoc == 0)

				break;

			len -= 2;

			continue;

			}

		q = p;

		/* Just read in a header: only care about the length */

		if(!asn1_check_tlen(&plen, NULL, NULL, &inf, NULL, &p, len,

				-1, 0, 0, NULL))

			{

			ASN1err(ASN1_F_ASN1_FIND_END, ERR_R_NESTED_ASN1_ERROR);

			return 0;

			}

		if (inf)

			expected_eoc++;

		else

			p += plen;

		len -= p - q;

		}

	if (expected_eoc)

		{

		ASN1err(ASN1_F_ASN1_FIND_END, ASN1_R_MISSING_EOC);

		return 0;

		}

	*in = p;

	return 1;

	}

/* This function collects the asn1 data from a constructred string

 * type into a buffer. The values of 'in' and 'len' should refer

 * to the contents of the constructed type and 'inf' should be set

 * if it is indefinite length. If 'buf' is NULL then we just want

 * to find the end of the current structure: useful for indefinite

 * length constructed stuff.

 * if it is indefinite length.

 */



static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len,