/*
* Copyright 2016 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
#ifdef OPENSSL_NO_CT
# error "CT is disabled"
#endif
#include <limits.h>
#include <string.h>
#include <openssl/asn1.h>
#include <openssl/buffer.h>
#include <openssl/ct.h>
#include <openssl/err.h>
#include "ct_local.h"
int o2i_SCT_signature(SCT *sct, const unsigned char **in, size_t len)
{
size_t siglen;
size_t len_remaining = len;
const unsigned char *p;
if (sct->version != SCT_VERSION_V1) {
CTerr(CT_F_O2I_SCT_SIGNATURE, CT_R_UNSUPPORTED_VERSION);
return -1;
}
/*
* digitally-signed struct header: (1 byte) Hash algorithm (1 byte)
* Signature algorithm (2 bytes + ?) Signature
*
* This explicitly rejects empty signatures: they're invalid for
* all supported algorithms.
*/
if (len <= 4) {
CTerr(CT_F_O2I_SCT_SIGNATURE, CT_R_SCT_INVALID_SIGNATURE);
return -1;
}
p = *in;
/* Get hash and signature algorithm */
sct->hash_alg = *p++;
sct->sig_alg = *p++;
if (SCT_get_signature_nid(sct) == NID_undef) {
CTerr(CT_F_O2I_SCT_SIGNATURE, CT_R_SCT_INVALID_SIGNATURE);
return -1;
}
/* Retrieve signature and check it is consistent with the buffer length */
n2s(p, siglen);
len_remaining -= (p - *in);
if (siglen > len_remaining) {
CTerr(CT_F_O2I_SCT_SIGNATURE, CT_R_SCT_INVALID_SIGNATURE);
return -1;
}
if (SCT_set1_signature(sct, p, siglen) != 1)
return -1;
len_remaining -= siglen;
*in = p + siglen;
return len - len_remaining;
}
SCT *o2i_SCT(SCT **psct, const unsigned char **in, size_t len)
{
SCT *sct = NULL;
const unsigned char *p;
if (len == 0 || len > MAX_SCT_SIZE) {
CTerr(CT_F_O2I_SCT, CT_R_SCT_INVALID);
goto err;
}
if ((sct = SCT_new()) == NULL)
goto err;
p = *in;
sct->version = *p;
if (sct->version == SCT_VERSION_V1) {
int sig_len;
size_t len2;
/*-
* Fixed-length header:
* struct {
* Version sct_version; (1 byte)
* log_id id; (32 bytes)
* uint64 timestamp; (8 bytes)
* CtExtensions extensions; (2 bytes + ?)
* }
*/
if (len < 43) {
CTerr(CT_F_O2I_SCT, CT_R_SCT_INVALID);
goto err;
}
len -= 43;
p++;
sct->log_id = BUF_memdup(p, CT_V1_HASHLEN);
if (sct->log_id == NULL)
goto err;
sct->log_id_len = CT_V1_HASHLEN;
p += CT_V1_HASHLEN;
n2l8(p, sct->timestamp);
n2s(p, len2);
if (len < len2) {
CTerr(CT_F_O2I_SCT, CT_R_SCT_INVALID);
goto err;
}
if (len2 > 0) {
sct->ext = BUF_memdup(p, len2);
if (sct->ext == NULL)
goto err;
}
sct->ext_len = len2;
p += len2;
len -= len2;
sig_len = o2i_SCT_signature(sct, &p, len);
if (sig_len <= 0) {
CTerr(CT_F_O2I_SCT, CT_R_SCT_INVALID);
goto err;
}
len -= sig_len;
*in = p + len;
} else {
/* If not V1 just cache encoding */
sct->sct = BUF_memdup(p, len);
if (sct->sct == NULL)
goto err;
sct->sct_len = len;
*in = p + len;
}
if (psct != NULL) {
SCT_free(*psct);
*psct = sct;
}
return sct;
err:
SCT_free(sct);
return NULL;
}
int i2o_SCT_signature(const SCT *sct, unsigned char **out)
{
size_t len;
unsigned char *p = NULL, *pstart = NULL;
if (!SCT_signature_is_complete(sct)) {
CTerr(CT_F_I2O_SCT_SIGNATURE, CT_R_SCT_INVALID_SIGNATURE);
goto err;
}
if (sct->version != SCT_VERSION_V1) {
CTerr(CT_F_I2O_SCT_SIGNATURE, CT_R_UNSUPPORTED_VERSION);
goto err;
}
/*
* (1 byte) Hash algorithm
* (1 byte) Signature algorithm
* (2 bytes + ?) Signature
*/
len = 4 + sct->sig_len;
if (out != NULL) {
if (*out != NULL) {
p = *out;
*out += len;
} else {
pstart = p = OPENSSL_malloc(len);
if (p == NULL) {
CTerr(CT_F_I2O_SCT_SIGNATURE, ERR_R_MALLOC_FAILURE);
goto err;
}
*out = p;
}
*p++ = sct->hash_alg;
*p++ = sct->sig_alg;
s2n(sct->sig_len, p);
memcpy(p, sct->sig, sct->sig_len);
}
return len;
err:
OPENSSL_free(pstart);
return -1;
}
int i2o_SCT(const SCT *sct, unsigned char **out)
{
size_t len;
unsigned char *p = NULL, *pstart = NULL;
if (!SCT_is_complete(sct)) {
CTerr(CT_F_I2O_SCT, CT_R_SCT_NOT_SET);
goto err;
}
/*
* Fixed-length header: struct { (1 byte) Version sct_version; (32 bytes)
* log_id id; (8 bytes) uint64 timestamp; (2 bytes + ?) CtExtensions
* extensions; (1 byte) Hash algorithm (1 byte) Signature algorithm (2
* bytes + ?) Signature
*/
if (sct->version == SCT_VERSION_V1)
len = 43 + sct->ext_len + 4 + sct->sig_len;
else
len = sct->sct_len;
if (out == NULL)
return len;
if (*out != NULL) {
p = *out;
*out += len;
} else {
pstart = p = OPENSSL_malloc(len);
if (p == NULL) {
CTerr(CT_F_I2O_SCT, ERR_R_MALLOC_FAILURE);
goto err;
}
*out = p;
}
if (sct->version == SCT_VERSION_V1) {
*p++ = sct->version;
memcpy(p, sct->log_id, CT_V1_HASHLEN);
p += CT_V1_HASHLEN;
l2n8(sct->timestamp, p);
s2n(sct->ext_len, p);
if (sct->ext_len > 0) {
memcpy(p, sct->ext, sct->ext_len);
p += sct->ext_len;
}
if (i2o_SCT_signature(sct, &p) <= 0)
goto err;
} else {
memcpy(p, sct->sct, len);
}
return len;
err:
OPENSSL_free(pstart);
return -1;
}
STACK_OF(SCT) *o2i_SCT_LIST(STACK_OF(SCT) **a, const unsigned char **pp,
size_t len)
{
STACK_OF(SCT) *sk = NULL;
size_t list_len, sct_len;
if (len < 2 || len > MAX_SCT_LIST_SIZE) {
CTerr(CT_F_O2I_SCT_LIST, CT_R_SCT_LIST_INVALID);
return NULL;
}
n2s(*pp, list_len);
if (list_len != len - 2) {
CTerr(CT_F_O2I_SCT_LIST, CT_R_SCT_LIST_INVALID);
return NULL;
}
if (a == NULL || *a == NULL) {
sk = sk_SCT_new_null();
if (sk == NULL)
return NULL;
} else {
SCT *sct;
/* Use the given stack, but empty it first. */
sk = *a;
while ((sct = sk_SCT_pop(sk)) != NULL)
SCT_free(sct);
}
while (list_len > 0) {
SCT *sct;
if (list_len < 2) {
CTerr(CT_F_O2I_SCT_LIST, CT_R_SCT_LIST_INVALID);
goto err;
}
n2s(*pp, sct_len);
list_len -= 2;
if (sct_len == 0 || sct_len > list_len) {
CTerr(CT_F_O2I_SCT_LIST, CT_R_SCT_LIST_INVALID);
goto err;
}
list_len -= sct_len;
if ((sct = o2i_SCT(NULL, pp, sct_len)) == NULL)
goto err;
if (!sk_SCT_push(sk, sct)) {
SCT_free(sct);
goto err;
}
}
if (a != NULL && *a == NULL)
*a = sk;
return sk;
err:
if (a == NULL || *a == NULL)
SCT_LIST_free(sk);
return NULL;
}
int i2o_SCT_LIST(const STACK_OF(SCT) *a, unsigned char **pp)
{
int len, sct_len, i, is_pp_new = 0;
size_t len2;
unsigned char *p = NULL, *p2;
if (pp != NULL) {
if (*pp == NULL) {
if ((len = i2o_SCT_LIST(a, NULL)) == -1) {
CTerr(CT_F_I2O_SCT_LIST, CT_R_SCT_LIST_INVALID);
return -1;
}
if ((*pp = OPENSSL_malloc(len)) == NULL) {
CTerr(CT_F_I2O_SCT_LIST, ERR_R_MALLOC_FAILURE);
return -1;
}
is_pp_new = 1;
}
p = *pp + 2;
}
len2 = 2;
for (i = 0; i < sk_SCT_num(a); i++) {
if (pp != NULL) {
p2 = p;
p += 2;
if ((sct_len = i2o_SCT(sk_SCT_value(a, i), &p)) == -1)
goto err;
s2n(sct_len, p2);
} else {
if ((sct_len = i2o_SCT(sk_SCT_value(a, i), NULL)) == -1)
goto err;
}
len2 += 2 + sct_len;
}
if (len2 > MAX_SCT_LIST_SIZE)
goto err;
if (pp != NULL) {
p = *pp;
s2n(len2 - 2, p);
if (!is_pp_new)
*pp += len2;
}
return len2;
err:
if (is_pp_new) {
OPENSSL_free(*pp);
*pp = NULL;
}
return -1;
}
STACK_OF(SCT) *d2i_SCT_LIST(STACK_OF(SCT) **a, const unsigned char **pp,
long len)
{
ASN1_OCTET_STRING *oct = NULL;
STACK_OF(SCT) *sk = NULL;
const unsigned char *p;
p = *pp;
if (d2i_ASN1_OCTET_STRING(&oct, &p, len) == NULL)
return NULL;
p = oct->data;
if ((sk = o2i_SCT_LIST(a, &p, oct->length)) != NULL)
*pp += len;
ASN1_OCTET_STRING_free(oct);
return sk;
}
int i2d_SCT_LIST(const STACK_OF(SCT) *a, unsigned char **out)
{
ASN1_OCTET_STRING oct;
int len;
oct.data = NULL;
if ((oct.length = i2o_SCT_LIST(a, &oct.data)) == -1)
return -1;
len = i2d_ASN1_OCTET_STRING(&oct, out);
OPENSSL_free(oct.data);
return len;
}