Parse DER tag mbedtls_x509_string_to_names

Signed-off-by: Agathiyan Bragadeesh <agathiyan.bragadeesh2@arm.com>
This commit is contained in:
Agathiyan Bragadeesh 2023-07-27 14:34:11 +01:00
parent ddc720d209
commit 6cbfae591a

View file

@ -30,6 +30,10 @@
#include "mbedtls/platform.h" #include "mbedtls/platform.h"
#if defined(MBEDTLS_ASN1_PARSE_C)
#include "mbedtls/asn1.h"
#endif
/* Structure linking OIDs for X.509 DN AttributeTypes to their /* Structure linking OIDs for X.509 DN AttributeTypes to their
* string representations and default string encodings used by Mbed TLS. */ * string representations and default string encodings used by Mbed TLS. */
typedef struct { typedef struct {
@ -171,12 +175,12 @@ static int hexpair_to_int(char c1, char c2)
} }
} }
static int parse_attribute_value_string(const char *s, int len, char *data, int *data_len) static int parse_attribute_value_string(const char *s, int len, unsigned char *data, size_t *data_len)
{ {
const char *c = s; const char *c = s;
const char *end = c + len; const char *end = c + len;
int hexpair = 0; int hexpair = 0;
char *d = data; unsigned char *d = data;
int n; int n;
while (c < end) { while (c < end) {
if (*c == '\\') { if (*c == '\\') {
@ -205,26 +209,42 @@ static int parse_attribute_value_string(const char *s, int len, char *data, int
return 0; return 0;
} }
static int parse_attribute_value_ber_encoded(const char *s, int len, char *data, int *data_len) static int parse_attribute_value_ber_encoded(const char *s, int len, unsigned char *data, size_t *data_len, int *tag)
{ {
const char *c = s; const char *c = s;
const char *end = c + len; const char *end = c + len;
char *d = data; unsigned char asn1_der_buf[256];
int tag, n; unsigned char *asn1_der_end;
if ((len < 5) || (*c != '#') || unsigned char *p;
((tag = unsigned char *d;
hexpair_to_int(*(c+1), *(c+2))) == -1) || ((*data_len = hexpair_to_int(*(c+3), *(c+4))) == -1)) { int n;
return MBEDTLS_ERR_X509_INVALID_NAME; /* Converting from hexstring to raw binary so we can use asn1parse.c*/
} if ((len < 5) || (*c != '#')) {
c += 5; return MBEDTLS_ERR_X509_INVALID_NAME;
}
while (c < end) { c++;
if((*tag = hexpair_to_int(*c, *(c+1))) == -1) {
return MBEDTLS_ERR_X509_INVALID_NAME;
}
c += 2;
p = asn1_der_buf;
for (p = asn1_der_buf; c < end; c += 2) {
if ((c + 1 >= end) || (n = hexpair_to_int(*c, *(c+1))) == -1) { if ((c + 1 >= end) || (n = hexpair_to_int(*c, *(c+1))) == -1) {
return MBEDTLS_ERR_X509_INVALID_NAME; return MBEDTLS_ERR_X509_INVALID_NAME;
} }
*(d++) = n; *(p++) = n;
c += 2;
} }
asn1_der_end = p;
p = asn1_der_buf;
if(mbedtls_asn1_get_len(&p, asn1_der_end, data_len) != 0) {
return MBEDTLS_ERR_X509_INVALID_NAME;
}
for (d = data; p < asn1_der_end; p++) {
*(d++) = *p;
}
return 0; return 0;
} }
@ -237,9 +257,10 @@ int mbedtls_x509_string_to_names(mbedtls_asn1_named_data **head, const char *nam
const char *oid = NULL; const char *oid = NULL;
const x509_attr_descriptor_t *attr_descr = NULL; const x509_attr_descriptor_t *attr_descr = NULL;
int in_tag = 1; int in_tag = 1;
int tag;
int numericoid = 0; int numericoid = 0;
char data[MBEDTLS_X509_MAX_DN_NAME_SIZE]; unsigned char data[MBEDTLS_X509_MAX_DN_NAME_SIZE];
int data_len = 0; size_t data_len = 0;
/* Clear existing chain if present */ /* Clear existing chain if present */
mbedtls_asn1_free_named_data_list(head); mbedtls_asn1_free_named_data_list(head);
@ -264,13 +285,14 @@ int mbedtls_x509_string_to_names(mbedtls_asn1_named_data **head, const char *nam
if (!in_tag && ((*c == ',' && *(c-1) != '\\') || c == end)) { if (!in_tag && ((*c == ',' && *(c-1) != '\\') || c == end)) {
if (!numericoid) { if (!numericoid) {
if ((parse_ret = parse_attribute_value_string(s, c - s, data, &data_len)) != 0) { if ((parse_ret = parse_attribute_value_string(s, c - s, data, &data_len)) != 0) {
return MBEDTLS_ERR_X509_INVALID_NAME; return parse_ret;
} }
tag = attr_descr->default_tag;
} }
if (numericoid) { if (numericoid) {
if ((parse_ret = if ((parse_ret =
parse_attribute_value_ber_encoded(s, c - s, data, &data_len)) != 0) { parse_attribute_value_ber_encoded(s, c - s, data, &data_len, &tag)) != 0) {
return MBEDTLS_ERR_X509_INVALID_NAME; return parse_ret;
} }
} }
mbedtls_asn1_named_data *cur = mbedtls_asn1_named_data *cur =
@ -282,7 +304,7 @@ int mbedtls_x509_string_to_names(mbedtls_asn1_named_data **head, const char *nam
} }
// set tagType // set tagType
cur->val.tag = attr_descr->default_tag; cur->val.tag = tag;
while (c < end && *(c + 1) == ' ') { while (c < end && *(c + 1) == ' ') {
c++; c++;