Update from stable branch.
[openssl.git] / crypto / asn1 / tasn_dec.c
index 2b9c25611ecd6c4fbac1ed2ec62a4d6a796bfe09..359e9c304bfd311166104c49942466212ac612f0 100644 (file)
@@ -1,5 +1,5 @@
 /* tasn_dec.c */
-/* Written by Dr Stephen N Henson (shenson@bigfoot.com) for the OpenSSL
+/* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
  * project 2000.
  */
 /* ====================================================================
@@ -69,7 +69,7 @@ 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);
+                       char inf, int tag, int aclass, int depth);
 
 static int collect_data(BUF_MEM *buf, const unsigned char **p, long plen);
 
@@ -93,12 +93,12 @@ static int asn1_d2i_ex_primitive(ASN1_VALUE **pval,
                                int tag, int aclass, char opt, ASN1_TLC *ctx);
 
 /* Table to convert tags to bit values, used for MSTRING type */
-static unsigned long tag2bit[32] = {
+static const unsigned long tag2bit[32] = {
 0,     0,      0,      B_ASN1_BIT_STRING,      /* tags  0 -  3 */
 B_ASN1_OCTET_STRING,   0,      0,              B_ASN1_UNKNOWN,/* tags  4- 7 */
 B_ASN1_UNKNOWN,        B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN,/* tags  8-11 */
 B_ASN1_UTF8STRING,B_ASN1_UNKNOWN,B_ASN1_UNKNOWN,B_ASN1_UNKNOWN,/* tags 12-15 */
-0,     0,      B_ASN1_NUMERICSTRING,B_ASN1_PRINTABLESTRING,   /* tags 16-19 */
+B_ASN1_SEQUENCE,0,B_ASN1_NUMERICSTRING,B_ASN1_PRINTABLESTRING, /* tags 16-19 */
 B_ASN1_T61STRING,B_ASN1_VIDEOTEXSTRING,B_ASN1_IA5STRING,       /* tags 20-22 */
 B_ASN1_UTCTIME, B_ASN1_GENERALIZEDTIME,                               /* tags 23-24 */ 
 B_ASN1_GRAPHICSTRING,B_ASN1_ISO64STRING,B_ASN1_GENERALSTRING,  /* tags 25-27 */
@@ -114,6 +114,8 @@ unsigned long ASN1_tag2bit(int tag)
 /* Macro to initialize and invalidate the cache */
 
 #define asn1_tlc_clear(c)      if (c) (c)->valid = 0
+/* Version to avoid compiler warning about 'c' always non-NULL */
+#define asn1_tlc_clear_nc(c)   (c)->valid = 0
 
 /* Decode an ASN1 item, this currently behaves just 
  * like a standard 'd2i' function. 'in' points to 
@@ -130,7 +132,7 @@ ASN1_VALUE *ASN1_item_d2i(ASN1_VALUE **pval,
        ASN1_VALUE *ptmpval = NULL;
        if (!pval)
                pval = &ptmpval;
-       asn1_tlc_clear(&c);
+       asn1_tlc_clear_nc(&c);
        if (ASN1_item_ex_d2i(pval, in, len, it, -1, 0, 0, &c) > 0) 
                return *pval;
        return NULL;
@@ -140,7 +142,7 @@ int ASN1_template_d2i(ASN1_VALUE **pval,
                const unsigned char **in, long len, const ASN1_TEMPLATE *tt)
        {
        ASN1_TLC c;
-       asn1_tlc_clear(&c);
+       asn1_tlc_clear_nc(&c);
        return asn1_template_ex_d2i(pval, in, len, tt, 0, &c);
        }
 
@@ -158,7 +160,7 @@ int ASN1_item_ex_d2i(ASN1_VALUE **pval, const unsigned char **in, long len,
        const ASN1_EXTERN_FUNCS *ef;
        const ASN1_AUX *aux = it->funcs;
        ASN1_aux_cb *asn1_cb;
-       const unsigned char *p, *q;
+       const unsigned char *p = NULL, *q;
        unsigned char *wp=NULL; /* BIG FAT WARNING!  BREAKS CONST WHERE USED */
        unsigned char imphack = 0, oclass;
        char seq_eoc, seq_nolen, cst, isopt;
@@ -283,6 +285,12 @@ int ASN1_item_ex_d2i(ASN1_VALUE **pval, const unsigned char **in, long len,
                        {
                        wp = *(unsigned char **)in;
                        imphack = *wp;
+                       if (p == NULL)
+                               {
+                               ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
+                                       ERR_R_NESTED_ASN1_ERROR);
+                               goto err;
+                               }
                        *wp = (unsigned char)((*p & V_ASN1_CONSTRUCTED)
                                                                | it->utype);
                        }
@@ -300,7 +308,7 @@ int ASN1_item_ex_d2i(ASN1_VALUE **pval, const unsigned char **in, long len,
 
 
                case ASN1_ITYPE_CHOICE:
-               if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it))
+               if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it, NULL))
                                goto auxerr;
 
                /* Allocate structure */
@@ -350,7 +358,7 @@ int ASN1_item_ex_d2i(ASN1_VALUE **pval, const unsigned char **in, long len,
 
                asn1_set_choice_selector(pval, i, it);
                *in = p;
-               if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it))
+               if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it, NULL))
                                goto auxerr;
                return 1;
 
@@ -397,7 +405,7 @@ int ASN1_item_ex_d2i(ASN1_VALUE **pval, const unsigned char **in, long len,
                        goto err;
                        }
 
-               if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it))
+               if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it, NULL))
                                goto auxerr;
 
                /* Get each field entry */
@@ -499,7 +507,7 @@ int ASN1_item_ex_d2i(ASN1_VALUE **pval, const unsigned char **in, long len,
                if (!asn1_enc_save(pval, *in, p - *in, it))
                        goto auxerr;
                *in = p;
-               if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it))
+               if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it, NULL))
                                goto auxerr;
                return 1;
 
@@ -660,11 +668,12 @@ static int asn1_template_noexp_d2i(ASN1_VALUE **val,
                else
                        {
                        /* We've got a valid STACK: free up any items present */
-                       STACK *sktmp = (STACK *)*val;
+                       STACK_OF(ASN1_VALUE) *sktmp
+                           = (STACK_OF(ASN1_VALUE) *)*val;
                        ASN1_VALUE *vtmp;
-                       while(sk_num(sktmp) > 0)
+                       while(sk_ASN1_VALUE_num(sktmp) > 0)
                                {
-                               vtmp = (ASN1_VALUE *)sk_pop(sktmp);
+                               vtmp = sk_ASN1_VALUE_pop(sktmp);
                                ASN1_item_ex_free(&vtmp,
                                                ASN1_ITEM_ptr(tt->item));
                                }
@@ -705,7 +714,8 @@ static int asn1_template_noexp_d2i(ASN1_VALUE **val,
                                goto err;
                                }
                        len -= p - q;
-                       if (!sk_push((STACK *)*val, (char *)skfield))
+                       if (!sk_ASN1_VALUE_push((STACK_OF(ASN1_VALUE) *)*val,
+                                               skfield))
                                {
                                ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
                                                ERR_R_MALLOC_FAILURE);
@@ -826,6 +836,7 @@ static int asn1_d2i_ex_primitive(ASN1_VALUE **pval,
                }
        else if (ret == -1)
                return -1;
+        ret = 0;
        /* SEQUENCE, SET and "OTHER" are left in encoded form */
        if ((utype == V_ASN1_SEQUENCE)
                || (utype == V_ASN1_SET) || (utype == V_ASN1_OTHER))
@@ -871,8 +882,11 @@ static int asn1_d2i_ex_primitive(ASN1_VALUE **pval,
                 * internally irrespective of the type. So instead just check
                 * for UNIVERSAL class and ignore the tag.
                 */
-               if (!asn1_collect(&buf, &p, plen, inf, -1, V_ASN1_UNIVERSAL))
+               if (!asn1_collect(&buf, &p, plen, inf, -1, V_ASN1_UNIVERSAL, 0))
+                       {
+                       free_cont = 1;
                        goto err;
+                       }
                len = buf.length;
                /* Append a final null to string */
                if (!BUF_MEM_grow_clean(&buf, len + 1))
@@ -924,6 +938,8 @@ int asn1_ex_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len,
                if (!*pval)
                        {
                        typ = ASN1_TYPE_new();
+                       if (typ == NULL)
+                               goto err;
                        *pval = (ASN1_VALUE *)typ;
                        }
                else
@@ -932,7 +948,7 @@ int asn1_ex_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len,
                if (utype != typ->type)
                        ASN1_TYPE_set(typ, utype, NULL);
                opval = pval;
-               pval = (ASN1_VALUE **)&typ->value.ptr;
+               pval = &typ->value.asn1_value;
                }
        switch(utype)
                {
@@ -1000,6 +1016,18 @@ int asn1_ex_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len,
                case V_ASN1_SET:
                case V_ASN1_SEQUENCE:
                default:
+               if (utype == V_ASN1_BMPSTRING && (len & 1))
+                       {
+                       ASN1err(ASN1_F_ASN1_EX_C2I,
+                                       ASN1_R_BMPSTRING_IS_WRONG_LENGTH);
+                       goto err;
+                       }
+               if (utype == V_ASN1_UNIVERSALSTRING && (len & 3))
+                       {
+                       ASN1err(ASN1_F_ASN1_EX_C2I,
+                                       ASN1_R_UNIVERSALSTRING_IS_WRONG_LENGTH);
+                       goto err;
+                       }
                /* All based on ASN1_STRING and handled the same */
                if (!*pval)
                        {
@@ -1116,8 +1144,18 @@ static int asn1_find_end(const unsigned char **in, long len, char inf)
  * if it is indefinite length.
  */
 
+#ifndef ASN1_MAX_STRING_NEST
+/* This determines how many levels of recursion are permitted in ASN1
+ * string types. If it is not limited stack overflows can occur. If set
+ * to zero no recursion is allowed at all. Although zero should be adequate
+ * examples exist that require a value of 1. So 5 should be more than enough.
+ */
+#define ASN1_MAX_STRING_NEST 5
+#endif
+
+
 static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len,
-                               char inf, int tag, int aclass)
+                       char inf, int tag, int aclass, int depth)
        {
        const unsigned char *p, *q;
        long plen;
@@ -1159,15 +1197,17 @@ static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len,
                /* If indefinite length constructed update max length */
                if (cst)
                        {
-#ifdef OPENSSL_ALLOW_NESTED_ASN1_STRINGS
-                       if (!asn1_collect(buf, &p, plen, ininf, tag, aclass))
+                       if (depth >= ASN1_MAX_STRING_NEST)
+                               {
+                               ASN1err(ASN1_F_ASN1_COLLECT,
+                                       ASN1_R_NESTED_ASN1_STRING);
+                               return 0;
+                               }
+                       if (!asn1_collect(buf, &p, plen, ininf, tag, aclass,
+                                               depth + 1))
                                return 0;
-#else
-                       ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_NESTED_ASN1_STRING);
-                       return 0;
-#endif
                        }
-               else if (!collect_data(buf, &p, plen))
+               else if (plen && !collect_data(buf, &p, plen))
                        return 0;
                len -= p - q;
                }