/*

 * Copyright 1995-2021 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

 */

/* Part of the code in here was originally in conf.c, which is now removed */

#include <stdio.h>

#include <string.h>

#include "internal/cryptlib.h"

#include "internal/o_dir.h"

#include <openssl/lhash.h>

#include <openssl/conf.h>

#include <openssl/conf_api.h>

#include "conf_def.h"

#include <openssl/buffer.h>

#include <openssl/err.h>

#ifndef OPENSSL_NO_POSIX_IO

# include <sys/stat.h>

# ifdef _WIN32

#  define stat    _stat

#  define strcasecmp _stricmp

# endif

#endif

#ifndef S_ISDIR

# define S_ISDIR(a) (((a) & S_IFMT) == S_IFDIR)

#endif

/*

 * The maximum length we can grow a value to after variable expansion. 64k

 * should be more than enough for all reasonable uses.

 */

#define MAX_CONF_VALUE_LENGTH       65536

static int is_keytype(const CONF *conf, char c, unsigned short type);

static char *eat_ws(CONF *conf, char *p);

static void trim_ws(CONF *conf, char *start);

static char *eat_alpha_numeric(CONF *conf, char *p);

static void clear_comments(CONF *conf, char *p);

static int str_copy(CONF *conf, char *section, char **to, char *from);

static char *scan_quote(CONF *conf, char *p);

static char *scan_dquote(CONF *conf, char *p);

#define scan_esc(conf,p)        (((IS_EOF((conf),(p)[1]))?((p)+1):((p)+2)))

#ifndef OPENSSL_NO_POSIX_IO

static BIO *process_include(char *include, OPENSSL_DIR_CTX **dirctx,

                            char **dirpath);

static BIO *get_next_file(const char *path, OPENSSL_DIR_CTX **dirctx);

#endif

static CONF *def_create(CONF_METHOD *meth);

static int def_init_default(CONF *conf);

static int def_init_WIN32(CONF *conf);

static int def_destroy(CONF *conf);

static int def_destroy_data(CONF *conf);

static int def_load(CONF *conf, const char *name, long *eline);

static int def_load_bio(CONF *conf, BIO *bp, long *eline);

static int def_dump(const CONF *conf, BIO *bp);

static int def_is_number(const CONF *conf, char c);

static int def_to_int(const CONF *conf, char c);

static CONF_METHOD default_method = {

    "OpenSSL default",

    def_create,

    def_init_default,

    def_destroy,

    def_destroy_data,

    def_load_bio,

    def_dump,

    def_is_number,

    def_to_int,

    def_load

};

static CONF_METHOD WIN32_method = {

    "WIN32",

    def_create,

    def_init_WIN32,

    def_destroy,

    def_destroy_data,

    def_load_bio,

    def_dump,

    def_is_number,

    def_to_int,

    def_load

};

CONF_METHOD *NCONF_default(void)

{

    return &default_method;

}

CONF_METHOD *NCONF_WIN32(void)

{

    return &WIN32_method;

}

static CONF *def_create(CONF_METHOD *meth)

{

    CONF *ret;

    ret = OPENSSL_malloc(sizeof(*ret));

    if (ret != NULL)

        if (meth->init(ret) == 0) {

            OPENSSL_free(ret);

            ret = NULL;

        }

    return ret;

}

static int def_init_default(CONF *conf)

{

    if (conf == NULL)

        return 0;

    conf->meth = &default_method;

    conf->meth_data = (void *)CONF_type_default;

    conf->data = NULL;

    return 1;

}

static int def_init_WIN32(CONF *conf)

{

    if (conf == NULL)

        return 0;

    conf->meth = &WIN32_method;

    conf->meth_data = (void *)CONF_type_win32;

    conf->data = NULL;

    return 1;

}

static int def_destroy(CONF *conf)

{

    if (def_destroy_data(conf)) {

        OPENSSL_free(conf);

        return 1;

    }

    return 0;

}

static int def_destroy_data(CONF *conf)

{

    if (conf == NULL)

        return 0;

    _CONF_free_data(conf);

    return 1;

}

static int def_load(CONF *conf, const char *name, long *line)

{

    int ret;

    BIO *in = NULL;

#ifdef OPENSSL_SYS_VMS

    in = BIO_new_file(name, "r");

#else

    in = BIO_new_file(name, "rb");

#endif

    if (in == NULL) {

        if (ERR_GET_REASON(ERR_peek_last_error()) == BIO_R_NO_SUCH_FILE)

            CONFerr(CONF_F_DEF_LOAD, CONF_R_NO_SUCH_FILE);

        else

            CONFerr(CONF_F_DEF_LOAD, ERR_R_SYS_LIB);

        return 0;

    }

    ret = def_load_bio(conf, in, line);

    BIO_free(in);

    return ret;

}

static int def_load_bio(CONF *conf, BIO *in, long *line)

{

/* The macro BUFSIZE conflicts with a system macro in VxWorks */

#define CONFBUFSIZE     512

    int bufnum = 0, i, ii;

    BUF_MEM *buff = NULL;

    char *s, *p, *end;

    int again;

    int first_call = 1;

    long eline = 0;

    char btmp[DECIMAL_SIZE(eline) + 1];

    CONF_VALUE *v = NULL, *tv;

    CONF_VALUE *sv = NULL;

    char *section = NULL, *buf;

    char *start, *psection, *pname;

    void *h = (void *)(conf->data);

    STACK_OF(BIO) *biosk = NULL;

#ifndef OPENSSL_NO_POSIX_IO

    char *dirpath = NULL;

    OPENSSL_DIR_CTX *dirctx = NULL;

#endif

    if ((buff = BUF_MEM_new()) == NULL) {

        CONFerr(CONF_F_DEF_LOAD_BIO, ERR_R_BUF_LIB);

        goto err;

    }

    section = OPENSSL_strdup("default");

    if (section == NULL) {

        CONFerr(CONF_F_DEF_LOAD_BIO, ERR_R_MALLOC_FAILURE);

        goto err;

    }

    if (_CONF_new_data(conf) == 0) {

        CONFerr(CONF_F_DEF_LOAD_BIO, ERR_R_MALLOC_FAILURE);

        goto err;

    }

    sv = _CONF_new_section(conf, section);

    if (sv == NULL) {

        CONFerr(CONF_F_DEF_LOAD_BIO, CONF_R_UNABLE_TO_CREATE_NEW_SECTION);

        goto err;

    }

    bufnum = 0;

    again = 0;

    for (;;) {

        if (!BUF_MEM_grow(buff, bufnum + CONFBUFSIZE)) {

            CONFerr(CONF_F_DEF_LOAD_BIO, ERR_R_BUF_LIB);

            goto err;

        }

        p = &(buff->data[bufnum]);

        *p = '\0';

 read_retry:

        BIO_gets(in, p, CONFBUFSIZE - 1);

        p[CONFBUFSIZE - 1] = '\0';

        ii = i = strlen(p);

        if (first_call) {

            /* Other BOMs imply unsupported multibyte encoding,

             * so don't strip them and let the error raise */

            const unsigned char utf8_bom[3] = {0xEF, 0xBB, 0xBF};

            if (i >= 3 && memcmp(p, utf8_bom, 3) == 0) {

                memmove(p, p + 3, i - 3);

                p[i - 3] = 0;

                i -= 3;

                ii -= 3;

            }

            first_call = 0;

        }

        if (i == 0 && !again) {

            /* the currently processed BIO is at EOF */

            BIO *parent;

#ifndef OPENSSL_NO_POSIX_IO

            /* continue processing with the next file from directory */

            if (dirctx != NULL) {

                BIO *next;

                if ((next = get_next_file(dirpath, &dirctx)) != NULL) {

                    BIO_vfree(in);

                    in = next;

                    goto read_retry;

                } else {

                    OPENSSL_free(dirpath);

                    dirpath = NULL;

                }

            }

#endif

            /* no more files in directory, continue with processing parent */

            if ((parent = sk_BIO_pop(biosk)) == NULL) {

                /* everything processed get out of the loop */

                break;

            } else {

                BIO_vfree(in);

                in = parent;

                goto read_retry;

            }

        }

        again = 0;

        while (i > 0) {

            if ((p[i - 1] != '\r') && (p[i - 1] != '\n'))

                break;

            else

                i--;

        }

        /*

         * we removed some trailing stuff so there is a new line on the end.

         */

        if (ii && i == ii)

            again = 1;          /* long line */

        else {

            p[i] = '\0';

            eline++;            /* another input line */

        }

        /* we now have a line with trailing \r\n removed */

        /* i is the number of bytes */

        bufnum += i;

        v = NULL;

        /* check for line continuation */

        if (bufnum >= 1) {

            /*

             * If we have bytes and the last char '\\' and second last char

             * is not '\\'

             */

            p = &(buff->data[bufnum - 1]);

            if (IS_ESC(conf, p[0]) && ((bufnum <= 1) || !IS_ESC(conf, p[-1]))) {

                bufnum--;

                again = 1;

            }

        }

        if (again)

            continue;

        bufnum = 0;

        buf = buff->data;

        clear_comments(conf, buf);

        s = eat_ws(conf, buf);

        if (IS_EOF(conf, *s))

            continue;           /* blank line */

        if (*s == '[') {

            char *ss;

            s++;

            start = eat_ws(conf, s);

            ss = start;

 again:

            end = eat_alpha_numeric(conf, ss);

            p = eat_ws(conf, end);

            if (*p != ']') {

                if (*p != '\0' && ss != p) {

                    ss = p;

                    goto again;

                }

                CONFerr(CONF_F_DEF_LOAD_BIO,

                        CONF_R_MISSING_CLOSE_SQUARE_BRACKET);

                goto err;

            }

            *end = '\0';

            if (!str_copy(conf, NULL, &section, start))

                goto err;

            if ((sv = _CONF_get_section(conf, section)) == NULL)

                sv = _CONF_new_section(conf, section);

            if (sv == NULL) {

                CONFerr(CONF_F_DEF_LOAD_BIO,

                        CONF_R_UNABLE_TO_CREATE_NEW_SECTION);

                goto err;

            }

            continue;

        } else {

            pname = s;

            end = eat_alpha_numeric(conf, s);

            if ((end[0] == ':') && (end[1] == ':')) {

                *end = '\0';

                end += 2;

                psection = pname;

                pname = end;

                end = eat_alpha_numeric(conf, end);

            } else {

                psection = section;

            }

            p = eat_ws(conf, end);

            if (strncmp(pname, ".include", 8) == 0

                && (p != pname + 8 || *p == '=')) {

                char *include = NULL;

                BIO *next;

                if (*p == '=') {

                    p++;

                    p = eat_ws(conf, p);

                }

                trim_ws(conf, p);

                if (!str_copy(conf, psection, &include, p))

                    goto err;

                /* get the BIO of the included file */

#ifndef OPENSSL_NO_POSIX_IO

                next = process_include(include, &dirctx, &dirpath);

                if (include != dirpath) {

                    /* dirpath will contain include in case of a directory */

                    OPENSSL_free(include);

                }

#else

                next = BIO_new_file(include, "r");

                OPENSSL_free(include);

#endif

                if (next != NULL) {

                    /* push the currently processing BIO onto stack */

                    if (biosk == NULL) {

                        if ((biosk = sk_BIO_new_null()) == NULL) {

                            CONFerr(CONF_F_DEF_LOAD_BIO, ERR_R_MALLOC_FAILURE);

                            BIO_free(next);

                            goto err;

                        }

                    }

                    if (!sk_BIO_push(biosk, in)) {

                        CONFerr(CONF_F_DEF_LOAD_BIO, ERR_R_MALLOC_FAILURE);

                        BIO_free(next);

                        goto err;

                    }

                    /* continue with reading from the included BIO */

                    in = next;

                }

                continue;

            } else if (*p != '=') {

                CONFerr(CONF_F_DEF_LOAD_BIO, CONF_R_MISSING_EQUAL_SIGN);

                goto err;

            }

            *end = '\0';

            p++;

            start = eat_ws(conf, p);

            trim_ws(conf, start);

            if ((v = OPENSSL_malloc(sizeof(*v))) == NULL) {

                CONFerr(CONF_F_DEF_LOAD_BIO, ERR_R_MALLOC_FAILURE);

                goto err;

            }

            v->name = OPENSSL_strdup(pname);

            v->value = NULL;

            if (v->name == NULL) {

                CONFerr(CONF_F_DEF_LOAD_BIO, ERR_R_MALLOC_FAILURE);

                goto err;

            }

            if (!str_copy(conf, psection, &(v->value), start))

                goto err;

            if (strcmp(psection, section) != 0) {

                if ((tv = _CONF_get_section(conf, psection))

                    == NULL)

                    tv = _CONF_new_section(conf, psection);

                if (tv == NULL) {

                    CONFerr(CONF_F_DEF_LOAD_BIO,

                            CONF_R_UNABLE_TO_CREATE_NEW_SECTION);

                    goto err;

                }

            } else

                tv = sv;

            if (_CONF_add_string(conf, tv, v) == 0) {

                CONFerr(CONF_F_DEF_LOAD_BIO, ERR_R_MALLOC_FAILURE);

                goto err;

            }

            v = NULL;

        }

    }

    BUF_MEM_free(buff);

    OPENSSL_free(section);

    /*

     * No need to pop, since we only get here if the stack is empty.

     * If this causes a BIO leak, THE ISSUE IS SOMEWHERE ELSE!

     */

    sk_BIO_free(biosk);

    return 1;

 err:

    BUF_MEM_free(buff);

    OPENSSL_free(section);

    /*

     * Since |in| is the first element of the stack and should NOT be freed

     * here, we cannot use sk_BIO_pop_free().  Instead, we pop and free one

     * BIO at a time, making sure that the last one popped isn't.

     */

    while (sk_BIO_num(biosk) > 0) {

        BIO *popped = sk_BIO_pop(biosk);

        BIO_vfree(in);

        in = popped;

    }

    sk_BIO_free(biosk);

#ifndef OPENSSL_NO_POSIX_IO

    OPENSSL_free(dirpath);

    if (dirctx != NULL)

        OPENSSL_DIR_end(&dirctx);

#endif

    if (line != NULL)

        *line = eline;

    BIO_snprintf(btmp, sizeof(btmp), "%ld", eline);

    ERR_add_error_data(2, "line ", btmp);

    if (h != conf->data) {

        CONF_free(conf->data);

        conf->data = NULL;

    }

    if (v != NULL) {

        OPENSSL_free(v->name);

        OPENSSL_free(v->value);

        OPENSSL_free(v);

    }

    return 0;

}

static void clear_comments(CONF *conf, char *p)

{

    for (;;) {

        if (IS_FCOMMENT(conf, *p)) {

            *p = '\0';

            return;

        }

        if (!IS_WS(conf, *p)) {

            break;

        }

        p++;

    }

    for (;;) {

        if (IS_COMMENT(conf, *p)) {

            *p = '\0';

            return;

        }

        if (IS_DQUOTE(conf, *p)) {

            p = scan_dquote(conf, p);

            continue;

        }

        if (IS_QUOTE(conf, *p)) {

            p = scan_quote(conf, p);

            continue;

        }

        if (IS_ESC(conf, *p)) {

            p = scan_esc(conf, p);

            continue;

        }

        if (IS_EOF(conf, *p))

            return;

        else

            p++;

    }

}

static int str_copy(CONF *conf, char *section, char **pto, char *from)

{

    int q, r, rr = 0, to = 0, len = 0;

    char *s, *e, *rp, *p, *rrp, *np, *cp, v;

    BUF_MEM *buf;

    if ((buf = BUF_MEM_new()) == NULL)

        return 0;

    len = strlen(from) + 1;

    if (!BUF_MEM_grow(buf, len))

        goto err;

    for (;;) {

        if (IS_QUOTE(conf, *from)) {

            q = *from;

            from++;

            while (!IS_EOF(conf, *from) && (*from != q)) {

                if (IS_ESC(conf, *from)) {

                    from++;

                    if (IS_EOF(conf, *from))

                        break;

                }

                buf->data[to++] = *(from++);

            }

            if (*from == q)

                from++;

        } else if (IS_DQUOTE(conf, *from)) {

            q = *from;

            from++;

            while (!IS_EOF(conf, *from)) {

                if (*from == q) {

                    if (*(from + 1) == q) {

                        from++;

                    } else {

                        break;

                    }

                }

                buf->data[to++] = *(from++);

            }

            if (*from == q)

                from++;

        } else if (IS_ESC(conf, *from)) {

            from++;

            v = *(from++);

            if (IS_EOF(conf, v))

                break;

            else if (v == 'r')

                v = '\r';

            else if (v == 'n')

                v = '\n';

            else if (v == 'b')

                v = '\b';

            else if (v == 't')

                v = '\t';

            buf->data[to++] = v;

        } else if (IS_EOF(conf, *from))

            break;

        else if (*from == '$') {

            size_t newsize;

            /* try to expand it */

            rrp = NULL;

            s = &(from[1]);

            if (*s == '{')

                q = '}';

            else if (*s == '(')

                q = ')';

            else

                q = 0;

            if (q)

                s++;

            cp = section;

            e = np = s;

            while (IS_ALNUM(conf, *e))

                e++;

            if ((e[0] == ':') && (e[1] == ':')) {

                cp = np;

                rrp = e;

                rr = *e;

                *rrp = '\0';

                e += 2;

                np = e;

                while (IS_ALNUM(conf, *e))

                    e++;

            }

            r = *e;

            *e = '\0';

            rp = e;

            if (q) {

                if (r != q) {

                    CONFerr(CONF_F_STR_COPY, CONF_R_NO_CLOSE_BRACE);

                    goto err;

                }

                e++;

            }

            /*-

             * So at this point we have

             * np which is the start of the name string which is

             *   '\0' terminated.

             * cp which is the start of the section string which is

             *   '\0' terminated.

             * e is the 'next point after'.

             * r and rr are the chars replaced by the '\0'

             * rp and rrp is where 'r' and 'rr' came from.

             */

            p = _CONF_get_string(conf, cp, np);

            if (rrp != NULL)

                *rrp = rr;

            *rp = r;

            if (p == NULL) {

                CONFerr(CONF_F_STR_COPY, CONF_R_VARIABLE_HAS_NO_VALUE);

                goto err;

            }

            newsize = strlen(p) + buf->length - (e - from);

            if (newsize > MAX_CONF_VALUE_LENGTH) {

                CONFerr(CONF_F_STR_COPY, CONF_R_VARIABLE_EXPANSION_TOO_LONG);

                goto err;

            }

            if (!BUF_MEM_grow_clean(buf, newsize)) {

                CONFerr(CONF_F_STR_COPY, ERR_R_MALLOC_FAILURE);

                goto err;

            }

            while (*p)

                buf->data[to++] = *(p++);

            /*

             * Since we change the pointer 'from', we also have to change the

             * perceived length of the string it points at.  /RL

             */

            len -= e - from;

            from = e;

            /*

             * In case there were no braces or parenthesis around the

             * variable reference, we have to put back the character that was

             * replaced with a '\0'.  /RL

             */

            *rp = r;

        } else

            buf->data[to++] = *(from++);

    }

    buf->data[to] = '\0';

    OPENSSL_free(*pto);

    *pto = buf->data;

    OPENSSL_free(buf);

    return 1;

 err:

    BUF_MEM_free(buf);

    return 0;

}

#ifndef OPENSSL_NO_POSIX_IO

/*

 * Check whether included path is a directory.

 * Returns next BIO to process and in case of a directory

 * also an opened directory context and the include path.

 */

static BIO *process_include(char *include, OPENSSL_DIR_CTX **dirctx,

                            char **dirpath)

{

    struct stat st = { 0 };

    BIO *next;

    if (stat(include, &st) < 0) {

        SYSerr(SYS_F_STAT, errno);

        ERR_add_error_data(1, include);

        /* missing include file is not fatal error */

        return NULL;

    }

    if (S_ISDIR(st.st_mode)) {

        if (*dirctx != NULL) {

            CONFerr(CONF_F_PROCESS_INCLUDE,

                    CONF_R_RECURSIVE_DIRECTORY_INCLUDE);

            ERR_add_error_data(1, include);

            return NULL;

        }

        /* a directory, load its contents */

        if ((next = get_next_file(include, dirctx)) != NULL)

            *dirpath = include;

        return next;

    }

    next = BIO_new_file(include, "r");

    return next;

}

/*

 * Get next file from the directory path.

 * Returns BIO of the next file to read and updates dirctx.

 */

static BIO *get_next_file(const char *path, OPENSSL_DIR_CTX **dirctx)

{

    const char *filename;

    size_t pathlen;

    pathlen = strlen(path);

    while ((filename = OPENSSL_DIR_read(dirctx, path)) != NULL) {

        size_t namelen;

        namelen = strlen(filename);

        if ((namelen > 5 && strcasecmp(filename + namelen - 5, ".conf") == 0)

            || (namelen > 4 && strcasecmp(filename + namelen - 4, ".cnf") == 0)) {

            size_t newlen;

            char *newpath;

            BIO *bio;

            newlen = pathlen + namelen + 2;

            newpath = OPENSSL_zalloc(newlen);

            if (newpath == NULL) {

                CONFerr(CONF_F_GET_NEXT_FILE, ERR_R_MALLOC_FAILURE);

                break;

            }

#ifdef OPENSSL_SYS_VMS

            /*

             * If the given path isn't clear VMS syntax,

             * we treat it as on Unix.

             */

            if (path[pathlen - 1] == ']'

                || path[pathlen - 1] == '>'

                || path[pathlen - 1] == ':') {

                /* Clear VMS directory syntax, just copy as is */

                OPENSSL_strlcpy(newpath, path, newlen);

            }

#endif

            if (newpath[0] == '\0') {

                OPENSSL_strlcpy(newpath, path, newlen);

                OPENSSL_strlcat(newpath, "/", newlen);

            }

            OPENSSL_strlcat(newpath, filename, newlen);

            bio = BIO_new_file(newpath, "r");

            OPENSSL_free(newpath);

            /* Errors when opening files are non-fatal. */

            if (bio != NULL)

                return bio;

        }

    }

    OPENSSL_DIR_end(dirctx);

    *dirctx = NULL;

    return NULL;

}

#endif

static int is_keytype(const CONF *conf, char c, unsigned short type)

{

    const unsigned short * keytypes = (const unsigned short *) conf->meth_data;

    unsigned char key = (unsigned char)c;

#ifdef CHARSET_EBCDIC

# if CHAR_BIT > 8

    if (key > 255) {

        /* key is out of range for os_toascii table */

        return 0;

    }

# endif

    /* convert key from ebcdic to ascii */

    key = os_toascii[key];

#endif

    if (key > 127) {

        /* key is not a seven bit ascii character */

        return 0;

    }

    return (keytypes[key] & type) ? 1 : 0;

}

static char *eat_ws(CONF *conf, char *p)

{

    while (IS_WS(conf, *p) && (!IS_EOF(conf, *p)))

        p++;

    return p;

}

static void trim_ws(CONF *conf, char *start)

{

    char *p = start;

    while (!IS_EOF(conf, *p))

        p++;

    p--;

    while ((p >= start) && IS_WS(conf, *p))

        p--;

    p++;

    *p = '\0';

}

static char *eat_alpha_numeric(CONF *conf, char *p)

{

    for (;;) {

        if (IS_ESC(conf, *p)) {

            p = scan_esc(conf, p);

            continue;

        }

        if (!IS_ALNUM_PUNCT(conf, *p))

            return p;

        p++;

    }

}

static char *scan_quote(CONF *conf, char *p)

{

    int q = *p;

    p++;

    while (!(IS_EOF(conf, *p)) && (*p != q)) {

        if (IS_ESC(conf, *p)) {

            p++;

            if (IS_EOF(conf, *p))

                return p;

        }

        p++;

    }

    if (*p == q)

        p++;

    return p;

}

static char *scan_dquote(CONF *conf, char *p)

{

    int q = *p;

    p++;

    while (!(IS_EOF(conf, *p))) {

        if (*p == q) {

            if (*(p + 1) == q) {

                p++;

            } else {

                break;

            }

        }

        p++;

    }

    if (*p == q)

        p++;

    return p;

}

static void dump_value_doall_arg(const CONF_VALUE *a, BIO *out)

{

    if (a->name)

        BIO_printf(out, "[%s] %s=%s\n", a->section, a->name, a->value);

    else

        BIO_printf(out, "[[%s]]\n", a->section);

}

IMPLEMENT_LHASH_DOALL_ARG_CONST(CONF_VALUE, BIO);