a_strex.c

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/* a_strex.c */
/* Written by Dr Stephen N Henson ([email protected]) for the OpenSSL
 * project 2000.
 */
/* ====================================================================
 * Copyright (c) 2000 The OpenSSL Project.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer. 
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. All advertising materials mentioning features or use of this
 *    software must display the following acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
 *
 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
 *    endorse or promote products derived from this software without
 *    prior written permission. For written permission, please contact
 *    [email protected].
 *
 * 5. Products derived from this software may not be called "OpenSSL"
 *    nor may "OpenSSL" appear in their names without prior written
 *    permission of the OpenSSL Project.
 *
 * 6. Redistributions of any form whatsoever must retain the following
 *    acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
 *
 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 * ====================================================================
 *
 * This product includes cryptographic software written by Eric Young
 * ([email protected]).  This product includes software written by Tim
 * Hudson ([email protected]).
 *
 */

#include <stdio.h>
#include <string.h>
#include "cryptlib.h"
#include <openssl/crypto.h>
#include <openssl/x509.h>
#include <openssl/asn1.h>

#include "charmap.h"

/* ASN1_STRING_print_ex() and X509_NAME_print_ex().
 * Enhanced string and name printing routines handling
 * multibyte characters, RFC2253 and a host of other
 * options.
 */


#define CHARTYPE_BS_ESC     (ASN1_STRFLGS_ESC_2253 | CHARTYPE_FIRST_ESC_2253 | CHARTYPE_LAST_ESC_2253)

#define ESC_FLAGS (ASN1_STRFLGS_ESC_2253 | \
          ASN1_STRFLGS_ESC_QUOTE | \
          ASN1_STRFLGS_ESC_CTRL | \
          ASN1_STRFLGS_ESC_MSB)


/* Three IO functions for sending data to memory, a BIO and
 * and a FILE pointer.
 */
#if 0               /* never used */
static int send_mem_chars(void *arg, const void *buf, int len)
{
    unsigned char **out = arg;
    if(!out) return 1;
    memcpy(*out, buf, len);
    *out += len;
    return 1;
}
#endif

static int send_bio_chars(void *arg, const void *buf, int len)
{
    if(!arg) return 1;
    if(BIO_write(arg, buf, len) != len) return 0;
    return 1;
}

static int send_fp_chars(void *arg, const void *buf, int len)
{
    if(!arg) return 1;
    if(fwrite(buf, 1, len, arg) != (unsigned int)len) return 0;
    return 1;
}

typedef int char_io(void *arg, const void *buf, int len);

/* This function handles display of
 * strings, one character at a time.
 * It is passed an unsigned long for each
 * character because it could come from 2 or even
 * 4 byte forms.
 */

static int do_esc_char(unsigned long c, unsigned char flags, char *do_quotes, char_io *io_ch, void *arg)
{
    unsigned char chflgs, chtmp;
    char tmphex[HEX_SIZE(long)+3];

    if(c > 0xffffffffL)
        return -1;
    if(c > 0xffff) {
        BIO_snprintf(tmphex, sizeof tmphex, "\\W%08lX", c);
        if(!io_ch(arg, tmphex, 10)) return -1;
        return 10;
    }
    if(c > 0xff) {
        BIO_snprintf(tmphex, sizeof tmphex, "\\U%04lX", c);
        if(!io_ch(arg, tmphex, 6)) return -1;
        return 6;
    }
    chtmp = (unsigned char)c;
    if(chtmp > 0x7f) chflgs = flags & ASN1_STRFLGS_ESC_MSB;
    else chflgs = char_type[chtmp] & flags;
    if(chflgs & CHARTYPE_BS_ESC) {
        /* If we don't escape with quotes, signal we need quotes */
        if(chflgs & ASN1_STRFLGS_ESC_QUOTE) {
            if(do_quotes) *do_quotes = 1;
            if(!io_ch(arg, &chtmp, 1)) return -1;
            return 1;
        }
        if(!io_ch(arg, "\\", 1)) return -1;
        if(!io_ch(arg, &chtmp, 1)) return -1;
        return 2;
    }
    if(chflgs & (ASN1_STRFLGS_ESC_CTRL|ASN1_STRFLGS_ESC_MSB)) {
        BIO_snprintf(tmphex, 11, "\\%02X", chtmp);
        if(!io_ch(arg, tmphex, 3)) return -1;
        return 3;
    }
    /* If we get this far and do any escaping at all must escape 
     * the escape character itself: backslash.
     */
    if (chtmp == '\\' && flags & ESC_FLAGS) {
        if(!io_ch(arg, "\\\\", 2)) return -1;
        return 2;
    }
    if(!io_ch(arg, &chtmp, 1)) return -1;
    return 1;
}

#define BUF_TYPE_WIDTH_MASK 0x7
#define BUF_TYPE_CONVUTF8   0x8

/* This function sends each character in a buffer to
 * do_esc_char(). It interprets the content formats
 * and converts to or from UTF8 as appropriate.
 */

static int do_buf(unsigned char *buf, int buflen,
            int type, unsigned char flags, char *quotes, char_io *io_ch, void *arg)
{
    int i, outlen, len;
    unsigned char orflags, *p, *q;
    unsigned long c;
    p = buf;
    q = buf + buflen;
    outlen = 0;
    while(p != q) {
        if(p == buf && flags & ASN1_STRFLGS_ESC_2253) orflags = CHARTYPE_FIRST_ESC_2253;
        else orflags = 0;
        switch(type & BUF_TYPE_WIDTH_MASK) {
            case 4:
            c = ((unsigned long)*p++) << 24;
            c |= ((unsigned long)*p++) << 16;
            c |= ((unsigned long)*p++) << 8;
            c |= *p++;
            break;

            case 2:
            c = ((unsigned long)*p++) << 8;
            c |= *p++;
            break;

            case 1:
            c = *p++;
            break;
            
            case 0:
            i = UTF8_getc(p, buflen, &c);
            if(i < 0) return -1;    /* Invalid UTF8String */
            p += i;
            break;
            default:
            return -1;  /* invalid width */
        }
        if (p == q && flags & ASN1_STRFLGS_ESC_2253) orflags = CHARTYPE_LAST_ESC_2253;
        if(type & BUF_TYPE_CONVUTF8) {
            unsigned char utfbuf[6];
            int utflen;
            utflen = UTF8_putc(utfbuf, sizeof utfbuf, c);
            for(i = 0; i < utflen; i++) {
                /* We don't need to worry about setting orflags correctly
                 * because if utflen==1 its value will be correct anyway 
                 * otherwise each character will be > 0x7f and so the 
                 * character will never be escaped on first and last.
                 */
                len = do_esc_char(utfbuf[i], (unsigned char)(flags | orflags), quotes, io_ch, arg);
                if(len < 0) return -1;
                outlen += len;
            }
        } else {
            len = do_esc_char(c, (unsigned char)(flags | orflags), quotes, io_ch, arg);
            if(len < 0) return -1;
            outlen += len;
        }
    }
    return outlen;
}

/* This function hex dumps a buffer of characters */

static int do_hex_dump(char_io *io_ch, void *arg, unsigned char *buf, int buflen)
{
    static const char hexdig[] = "0123456789ABCDEF";
    unsigned char *p, *q;
    char hextmp[2];
    if(arg) {
        p = buf;
        q = buf + buflen;
        while(p != q) {
            hextmp[0] = hexdig[*p >> 4];
            hextmp[1] = hexdig[*p & 0xf];
            if(!io_ch(arg, hextmp, 2)) return -1;
            p++;
        }
    }
    return buflen << 1;
}

/* "dump" a string. This is done when the type is unknown,
 * or the flags request it. We can either dump the content
 * octets or the entire DER encoding. This uses the RFC2253
 * #01234 format.
 */

static int do_dump(unsigned long lflags, char_io *io_ch, void *arg, ASN1_STRING *str)
{
    /* Placing the ASN1_STRING in a temp ASN1_TYPE allows
     * the DER encoding to readily obtained
     */
    ASN1_TYPE t;
    unsigned char *der_buf, *p;
    int outlen, der_len;

    if(!io_ch(arg, "#", 1)) return -1;
    /* If we don't dump DER encoding just dump content octets */
    if(!(lflags & ASN1_STRFLGS_DUMP_DER)) {
        outlen = do_hex_dump(io_ch, arg, str->data, str->length);
        if(outlen < 0) return -1;
        return outlen + 1;
    }
    t.type = str->type;
    t.value.ptr = (char *)str;
    der_len = i2d_ASN1_TYPE(&t, NULL);
    der_buf = OPENSSL_malloc(der_len);
    if(!der_buf) return -1;
    p = der_buf;
    i2d_ASN1_TYPE(&t, &p);
    outlen = do_hex_dump(io_ch, arg, der_buf, der_len);
    OPENSSL_free(der_buf);
    if(outlen < 0) return -1;
    return outlen + 1;
}

/* Lookup table to convert tags to character widths,
 * 0 = UTF8 encoded, -1 is used for non string types
 * otherwise it is the number of bytes per character
 */

static const signed char tag2nbyte[] = {
    -1, -1, -1, -1, -1, /* 0-4 */
    -1, -1, -1, -1, -1, /* 5-9 */
    -1, -1, 0, -1,      /* 10-13 */
    -1, -1, -1, -1,     /* 15-17 */
    -1, 1, 1,       /* 18-20 */
    -1, 1, 1, 1,        /* 21-24 */
    -1, 1, -1,      /* 25-27 */
    4, -1, 2        /* 28-30 */
};

/* This is the main function, print out an
 * ASN1_STRING taking note of various escape
 * and display options. Returns number of
 * characters written or -1 if an error
 * occurred.
 */

static int do_print_ex(char_io *io_ch, void *arg, unsigned long lflags, ASN1_STRING *str)
{
    int outlen, len;
    int type;
    char quotes;
    unsigned char flags;
    quotes = 0;
    /* Keep a copy of escape flags */
    flags = (unsigned char)(lflags & ESC_FLAGS);

    type = str->type;

    outlen = 0;


    if(lflags & ASN1_STRFLGS_SHOW_TYPE) {
        const char *tagname;
        tagname = ASN1_tag2str(type);
        outlen += strlen(tagname);
        if(!io_ch(arg, tagname, outlen) || !io_ch(arg, ":", 1)) return -1; 
        outlen++;
    }

    /* Decide what to do with type, either dump content or display it */

    /* Dump everything */
    if(lflags & ASN1_STRFLGS_DUMP_ALL) type = -1;
    /* Ignore the string type */
    else if(lflags & ASN1_STRFLGS_IGNORE_TYPE) type = 1;
    else {
        /* Else determine width based on type */
        if((type > 0) && (type < 31)) type = tag2nbyte[type];
        else type = -1;
        if((type == -1) && !(lflags & ASN1_STRFLGS_DUMP_UNKNOWN)) type = 1;
    }

    if(type == -1) {
        len = do_dump(lflags, io_ch, arg, str);
        if(len < 0) return -1;
        outlen += len;
        return outlen;
    }

    if(lflags & ASN1_STRFLGS_UTF8_CONVERT) {
        /* Note: if string is UTF8 and we want
         * to convert to UTF8 then we just interpret
         * it as 1 byte per character to avoid converting
         * twice.
         */
        if(!type) type = 1;
        else type |= BUF_TYPE_CONVUTF8;
    }

    len = do_buf(str->data, str->length, type, flags, &quotes, io_ch, NULL);
    if(len < 0) return -1;
    outlen += len;
    if(quotes) outlen += 2;
    if(!arg) return outlen;
    if(quotes && !io_ch(arg, "\"", 1)) return -1;
    if(do_buf(str->data, str->length, type, flags, NULL, io_ch, arg) < 0)
        return -1;
    if(quotes && !io_ch(arg, "\"", 1)) return -1;
    return outlen;
}

/* Used for line indenting: print 'indent' spaces */

static int do_indent(char_io *io_ch, void *arg, int indent)
{
    int i;
    for(i = 0; i < indent; i++)
            if(!io_ch(arg, " ", 1)) return 0;
    return 1;
}

#define FN_WIDTH_LN 25
#define FN_WIDTH_SN 10

static int do_name_ex(char_io *io_ch, void *arg, X509_NAME *n,
                int indent, unsigned long flags)
{
    int i, prev = -1, orflags, cnt;
    int fn_opt, fn_nid;
    ASN1_OBJECT *fn;
    ASN1_STRING *val;
    X509_NAME_ENTRY *ent;
    char objtmp[80];
    const char *objbuf;
    int outlen, len;
    char *sep_dn, *sep_mv, *sep_eq;
    int sep_dn_len, sep_mv_len, sep_eq_len;
    if(indent < 0) indent = 0;
    outlen = indent;
    if(!do_indent(io_ch, arg, indent)) return -1;
    switch (flags & XN_FLAG_SEP_MASK)
    {
        case XN_FLAG_SEP_MULTILINE:
        sep_dn = "\n";
        sep_dn_len = 1;
        sep_mv = " + ";
        sep_mv_len = 3;
        break;

        case XN_FLAG_SEP_COMMA_PLUS:
        sep_dn = ",";
        sep_dn_len = 1;
        sep_mv = "+";
        sep_mv_len = 1;
        indent = 0;
        break;

        case XN_FLAG_SEP_CPLUS_SPC:
        sep_dn = ", ";
        sep_dn_len = 2;
        sep_mv = " + ";
        sep_mv_len = 3;
        indent = 0;
        break;

        case XN_FLAG_SEP_SPLUS_SPC:
        sep_dn = "; ";
        sep_dn_len = 2;
        sep_mv = " + ";
        sep_mv_len = 3;
        indent = 0;
        break;

        default:
        return -1;
    }

    if(flags & XN_FLAG_SPC_EQ) {
        sep_eq = " = ";
        sep_eq_len = 3;
    } else {
        sep_eq = "=";
        sep_eq_len = 1;
    }

    fn_opt = flags & XN_FLAG_FN_MASK;

    cnt = X509_NAME_entry_count(n); 
    for(i = 0; i < cnt; i++) {
        if(flags & XN_FLAG_DN_REV)
                ent = X509_NAME_get_entry(n, cnt - i - 1);
        else ent = X509_NAME_get_entry(n, i);
        if(prev != -1) {
            if(prev == ent->set) {
                if(!io_ch(arg, sep_mv, sep_mv_len)) return -1;
                outlen += sep_mv_len;
            } else {
                if(!io_ch(arg, sep_dn, sep_dn_len)) return -1;
                outlen += sep_dn_len;
                if(!do_indent(io_ch, arg, indent)) return -1;
                outlen += indent;
            }
        }
        prev = ent->set;
        fn = X509_NAME_ENTRY_get_object(ent);
        val = X509_NAME_ENTRY_get_data(ent);
        fn_nid = OBJ_obj2nid(fn);
        if(fn_opt != XN_FLAG_FN_NONE) {
            int objlen, fld_len;
            if((fn_opt == XN_FLAG_FN_OID) || (fn_nid==NID_undef) ) {
                OBJ_obj2txt(objtmp, sizeof objtmp, fn, 1);
                fld_len = 0; /* XXX: what should this be? */
                objbuf = objtmp;
            } else {
                if(fn_opt == XN_FLAG_FN_SN) {
                    fld_len = FN_WIDTH_SN;
                    objbuf = OBJ_nid2sn(fn_nid);
                } else if(fn_opt == XN_FLAG_FN_LN) {
                    fld_len = FN_WIDTH_LN;
                    objbuf = OBJ_nid2ln(fn_nid);
                } else {
                    fld_len = 0; /* XXX: what should this be? */
                    objbuf = "";
                }
            }
            objlen = strlen(objbuf);
            if(!io_ch(arg, objbuf, objlen)) return -1;
            if ((objlen < fld_len) && (flags & XN_FLAG_FN_ALIGN)) {
                if (!do_indent(io_ch, arg, fld_len - objlen)) return -1;
                outlen += fld_len - objlen;
            }
            if(!io_ch(arg, sep_eq, sep_eq_len)) return -1;
            outlen += objlen + sep_eq_len;
        }
        /* If the field name is unknown then fix up the DER dump
         * flag. We might want to limit this further so it will
         * DER dump on anything other than a few 'standard' fields.
         */
        if((fn_nid == NID_undef) && (flags & XN_FLAG_DUMP_UNKNOWN_FIELDS)) 
                    orflags = ASN1_STRFLGS_DUMP_ALL;
        else orflags = 0;
     
        len = do_print_ex(io_ch, arg, flags | orflags, val);
        if(len < 0) return -1;
        outlen += len;
    }
    return outlen;
}

/* Wrappers round the main functions */

int X509_NAME_print_ex(BIO *out, X509_NAME *nm, int indent, unsigned long flags)
{
    if(flags == XN_FLAG_COMPAT)
        return X509_NAME_print(out, nm, indent);
    return do_name_ex(send_bio_chars, out, nm, indent, flags);
}

#ifndef OPENSSL_NO_FP_API
int X509_NAME_print_ex_fp(FILE *fp, X509_NAME *nm, int indent, unsigned long flags)
{
    if(flags == XN_FLAG_COMPAT)
        {
        BIO *btmp;
        int ret;
        btmp = BIO_new_fp(fp, BIO_NOCLOSE);
        if(!btmp) return -1;
        ret = X509_NAME_print(btmp, nm, indent);
        BIO_free(btmp);
        return ret;
        }
    return do_name_ex(send_fp_chars, fp, nm, indent, flags);
}
#endif

int ASN1_STRING_print_ex(BIO *out, ASN1_STRING *str, unsigned long flags)
{
    return do_print_ex(send_bio_chars, out, flags, str);
}

#ifndef OPENSSL_NO_FP_API
int ASN1_STRING_print_ex_fp(FILE *fp, ASN1_STRING *str, unsigned long flags)
{
    return do_print_ex(send_fp_chars, fp, flags, str);
}
#endif

/* Utility function: convert any string type to UTF8, returns number of bytes
 * in output string or a negative error code
 */

int ASN1_STRING_to_UTF8(unsigned char **out, ASN1_STRING *in)
{
    ASN1_STRING stmp, *str = &stmp;
    int mbflag, type, ret;
    if(!in) return -1;
    type = in->type;
    if((type < 0) || (type > 30)) return -1;
    mbflag = tag2nbyte[type];
    if(mbflag == -1) return -1;
    mbflag |= MBSTRING_FLAG;
    stmp.data = NULL;
    ret = ASN1_mbstring_copy(&str, in->data, in->length, mbflag, B_ASN1_UTF8STRING);
    if(ret < 0) return ret;
    *out = stmp.data;
    return stmp.length;
}