/*

 * Copyright 2000-2024 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the Apache License 2.0 (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

 */

#include <stdio.h>

#include <string.h>

#include "internal/cryptlib.h"

#include "internal/sizes.h"

#include "crypto/asn1.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_2254 | \

                  ASN1_STRFLGS_ESC_QUOTE | \

                  ASN1_STRFLGS_ESC_CTRL | \

                  ASN1_STRFLGS_ESC_MSB)

/*

 * Three IO functions for sending data to memory, a BIO and a FILE

 * pointer.

 */

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;

}

#ifndef OPENSSL_NO_STDIO

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;

}

#endif

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 short flags, char *do_quotes,

                       char_io *io_ch, void *arg)

{

    unsigned short chflgs;

    unsigned char 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

                  | ASN1_STRFLGS_ESC_2254)) {

        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 short flags, char *quotes, char_io *io_ch,

                  void *arg)

{

    int i, outlen, len, charwidth;

    unsigned short orflags;

    unsigned char *p, *q;

    unsigned long c;

    p = buf;

    q = buf + buflen;

    outlen = 0;

    charwidth = type & BUF_TYPE_WIDTH_MASK;

    switch (charwidth) {

    case 4:

        if (buflen & 3) {

            ERR_raise(ERR_LIB_ASN1, ASN1_R_INVALID_UNIVERSALSTRING_LENGTH);

            return -1;

        }

        break;

    case 2:

        if (buflen & 1) {

            ERR_raise(ERR_LIB_ASN1, ASN1_R_INVALID_BMPSTRING_LENGTH);

            return -1;

        }

        break;

    default:

        break;

    }

    while (p != q) {

        if (p == buf && flags & ASN1_STRFLGS_ESC_2253)

            orflags = CHARTYPE_FIRST_ESC_2253;

        else

            orflags = 0;

        switch (charwidth) {

        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 */

            buflen -= i;

            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], flags | orflags, quotes,

                                  io_ch, arg);

                if (len < 0)

                    return -1;

                outlen += len;

            }

        } else {

            len = do_esc_char(c, 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,

                   const 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);

    if (der_len <= 0)

        return -1;

    if ((der_buf = OPENSSL_malloc(der_len)) == NULL)

        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,                     /* 10-11 */

     0,                         /* 12 V_ASN1_UTF8STRING */

    -1, -1, -1, -1, -1,         /* 13-17 */

     1,                         /* 18 V_ASN1_NUMERICSTRING */

     1,                         /* 19 V_ASN1_PRINTABLESTRING */

     1,                         /* 20 V_ASN1_T61STRING */

    -1,                         /* 21 */

     1,                         /* 22 V_ASN1_IA5STRING */

     1,                         /* 23 V_ASN1_UTCTIME */

     1,                         /* 24 V_ASN1_GENERALIZEDTIME */

    -1,                         /* 25 */

     1,                         /* 26 V_ASN1_ISO64STRING */

    -1,                         /* 27 */

     4,                         /* 28 V_ASN1_UNIVERSALSTRING */

    -1,                         /* 29 */

     2                          /* 30 V_ASN1_BMPSTRING */

};

/*

 * 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,

                       const ASN1_STRING *str)

{

    int outlen, len;

    int type;

    char quotes;

    unsigned short flags;

    quotes = 0;

    /* Keep a copy of escape flags */

    flags = (unsigned short)(lflags & ESC_FLAGS);

    type = str->type;

    outlen = 0;

    if (lflags & ASN1_STRFLGS_SHOW_TYPE) {

        const char *tagname;

        tagname = ASN1_tag2str(type);

        /* We can directly cast here as tagname will never be too large. */

        outlen += (int)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 || len > INT_MAX - outlen)

            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 || len > INT_MAX - 2 - outlen)

        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, const X509_NAME *n,

                      int indent, unsigned long flags)

{

    int i, prev = -1, orflags, cnt;

    int fn_opt, fn_nid;

    ASN1_OBJECT *fn;

    const ASN1_STRING *val;

    const 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 == X509_NAME_ENTRY_set(ent)) {

                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 = X509_NAME_ENTRY_set(ent);

        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, const 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_STDIO

int X509_NAME_print_ex_fp(FILE *fp, const 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, const ASN1_STRING *str, unsigned long flags)

{

    return do_print_ex(send_bio_chars, out, flags, str);

}

#ifndef OPENSSL_NO_STDIO

int ASN1_STRING_print_ex_fp(FILE *fp, const 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, const 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;

    stmp.length = 0;

    stmp.flags = 0;

    ret =

        ASN1_mbstring_copy(&str, in->data, in->length, mbflag,

                           B_ASN1_UTF8STRING);

    if (ret < 0)

        return ret;

    *out = stmp.data;

    return stmp.length;

}