/*

 * Copyright 2000-2016 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

 */

#include "dso_local.h"

#ifdef DSO_DL

# include <dl.h>

/* Part of the hack in "dl_load" ... */

# define DSO_MAX_TRANSLATED_SIZE 256

static int dl_load(DSO *dso);

static int dl_unload(DSO *dso);

static DSO_FUNC_TYPE dl_bind_func(DSO *dso, const char *symname);

static char *dl_name_converter(DSO *dso, const char *filename);

static char *dl_merger(DSO *dso, const char *filespec1,

                       const char *filespec2);

static int dl_pathbyaddr(void *addr, char *path, int sz);

static void *dl_globallookup(const char *name);

static DSO_METHOD dso_meth_dl = {

    "OpenSSL 'dl' shared library method",

    dl_load,

    dl_unload,

    dl_bind_func,

    NULL,                       /* ctrl */

    dl_name_converter,

    dl_merger,

    NULL,                       /* init */

    NULL,                       /* finish */

    dl_pathbyaddr,

    dl_globallookup

};

DSO_METHOD *DSO_METHOD_openssl(void)

{

    return &dso_meth_dl;

}

/*

 * For this DSO_METHOD, our meth_data STACK will contain; (i) the handle

 * (shl_t) returned from shl_load(). NB: I checked on HPUX11 and shl_t is

 * itself a pointer type so the cast is safe.

 */

static int dl_load(DSO *dso)

{

    shl_t ptr = NULL;

    /*

     * We don't do any fancy retries or anything, just take the method's (or

     * DSO's if it has the callback set) best translation of the

     * platform-independent filename and try once with that.

     */

    char *filename = DSO_convert_filename(dso, NULL);

    if (filename == NULL) {

        DSOerr(DSO_F_DL_LOAD, DSO_R_NO_FILENAME);

        goto err;

    }

    ptr = shl_load(filename, BIND_IMMEDIATE |

                   (dso->flags & DSO_FLAG_NO_NAME_TRANSLATION ? 0 :

                    DYNAMIC_PATH), 0L);

    if (ptr == NULL) {

        char errbuf[160];

        DSOerr(DSO_F_DL_LOAD, DSO_R_LOAD_FAILED);

        if (openssl_strerror_r(errno, errbuf, sizeof(errbuf)))

            ERR_add_error_data(4, "filename(", filename, "): ", errbuf);

        goto err;

    }

    if (!sk_push(dso->meth_data, (char *)ptr)) {

        DSOerr(DSO_F_DL_LOAD, DSO_R_STACK_ERROR);

        goto err;

    }

    /*

     * Success, stick the converted filename we've loaded under into the DSO

     * (it also serves as the indicator that we are currently loaded).

     */

    dso->loaded_filename = filename;

    return 1;

 err:

    /* Cleanup! */

    OPENSSL_free(filename);

    if (ptr != NULL)

        shl_unload(ptr);

    return 0;

}

static int dl_unload(DSO *dso)

{

    shl_t ptr;

    if (dso == NULL) {

        DSOerr(DSO_F_DL_UNLOAD, ERR_R_PASSED_NULL_PARAMETER);

        return 0;

    }

    if (sk_num(dso->meth_data) < 1)

        return 1;

    /* Is this statement legal? */

    ptr = (shl_t) sk_pop(dso->meth_data);

    if (ptr == NULL) {

        DSOerr(DSO_F_DL_UNLOAD, DSO_R_NULL_HANDLE);

        /*

         * Should push the value back onto the stack in case of a retry.

         */

        sk_push(dso->meth_data, (char *)ptr);

        return 0;

    }

    shl_unload(ptr);

    return 1;

}

static DSO_FUNC_TYPE dl_bind_func(DSO *dso, const char *symname)

{

    shl_t ptr;

    void *sym;

    if ((dso == NULL) || (symname == NULL)) {

        DSOerr(DSO_F_DL_BIND_FUNC, ERR_R_PASSED_NULL_PARAMETER);

        return NULL;

    }

    if (sk_num(dso->meth_data) < 1) {

        DSOerr(DSO_F_DL_BIND_FUNC, DSO_R_STACK_ERROR);

        return NULL;

    }

    ptr = (shl_t) sk_value(dso->meth_data, sk_num(dso->meth_data) - 1);

    if (ptr == NULL) {

        DSOerr(DSO_F_DL_BIND_FUNC, DSO_R_NULL_HANDLE);

        return NULL;

    }

    if (shl_findsym(&ptr, symname, TYPE_UNDEFINED, &sym) < 0) {

        char errbuf[160];

        DSOerr(DSO_F_DL_BIND_FUNC, DSO_R_SYM_FAILURE);

        if (openssl_strerror_r(errno, errbuf, sizeof(errbuf)))

            ERR_add_error_data(4, "symname(", symname, "): ", errbuf);

        return NULL;

    }

    return (DSO_FUNC_TYPE)sym;

}

static char *dl_merger(DSO *dso, const char *filespec1, const char *filespec2)

{

    char *merged;

    if (!filespec1 && !filespec2) {

        DSOerr(DSO_F_DL_MERGER, ERR_R_PASSED_NULL_PARAMETER);

        return NULL;

    }

    /*

     * If the first file specification is a rooted path, it rules. same goes

     * if the second file specification is missing.

     */

    if (!filespec2 || filespec1[0] == '/') {

        merged = OPENSSL_strdup(filespec1);

        if (merged == NULL) {

            DSOerr(DSO_F_DL_MERGER, ERR_R_MALLOC_FAILURE);

            return NULL;

        }

    }

    /*

     * If the first file specification is missing, the second one rules.

     */

    else if (!filespec1) {

        merged = OPENSSL_strdup(filespec2);

        if (merged == NULL) {

            DSOerr(DSO_F_DL_MERGER, ERR_R_MALLOC_FAILURE);

            return NULL;

        }

    } else

        /*

         * This part isn't as trivial as it looks.  It assumes that the

         * second file specification really is a directory, and makes no

         * checks whatsoever.  Therefore, the result becomes the

         * concatenation of filespec2 followed by a slash followed by

         * filespec1.

         */

    {

        int spec2len, len;

        spec2len = (filespec2 ? strlen(filespec2) : 0);

        len = spec2len + (filespec1 ? strlen(filespec1) : 0);

        if (spec2len && filespec2[spec2len - 1] == '/') {

            spec2len--;

            len--;

        }

        merged = OPENSSL_malloc(len + 2);

        if (merged == NULL) {

            DSOerr(DSO_F_DL_MERGER, ERR_R_MALLOC_FAILURE);

            return NULL;

        }

        strcpy(merged, filespec2);

        merged[spec2len] = '/';

        strcpy(&merged[spec2len + 1], filespec1);

    }

    return merged;

}

/*

 * This function is identical to the one in dso_dlfcn.c, but as it is highly

 * unlikely that both the "dl" *and* "dlfcn" variants are being compiled at

 * the same time, there's no great duplicating the code. Figuring out an

 * elegant way to share one copy of the code would be more difficult and

 * would not leave the implementations independent.

 */

static char *dl_name_converter(DSO *dso, const char *filename)

{

    char *translated;

    int len, rsize, transform;

    len = strlen(filename);

    rsize = len + 1;

    transform = (strstr(filename, "/") == NULL);

    {

        /* We will convert this to "%s.s?" or "lib%s.s?" */

        rsize += strlen(DSO_EXTENSION); /* The length of ".s?" */

        if ((DSO_flags(dso) & DSO_FLAG_NAME_TRANSLATION_EXT_ONLY) == 0)

            rsize += 3;         /* The length of "lib" */

    }

    translated = OPENSSL_malloc(rsize);

    if (translated == NULL) {

        DSOerr(DSO_F_DL_NAME_CONVERTER, DSO_R_NAME_TRANSLATION_FAILED);

        return NULL;

    }

    if (transform) {

        if ((DSO_flags(dso) & DSO_FLAG_NAME_TRANSLATION_EXT_ONLY) == 0)

            sprintf(translated, "lib%s%s", filename, DSO_EXTENSION);

        else

            sprintf(translated, "%s%s", filename, DSO_EXTENSION);

    } else

        sprintf(translated, "%s", filename);

    return translated;

}

static int dl_pathbyaddr(void *addr, char *path, int sz)

{

    struct shl_descriptor inf;

    int i, len;

    if (addr == NULL) {

        union {

            int (*f) (void *, char *, int);

            void *p;

        } t = {

            dl_pathbyaddr

        };

        addr = t.p;

    }

    for (i = -1; shl_get_r(i, &inf) == 0; i++) {

        if (((size_t)addr >= inf.tstart && (size_t)addr < inf.tend) ||

            ((size_t)addr >= inf.dstart && (size_t)addr < inf.dend)) {

            len = (int)strlen(inf.filename);

            if (sz <= 0)

                return len + 1;

            if (len >= sz)

                len = sz - 1;

            memcpy(path, inf.filename, len);

            path[len++] = 0;

            return len;

        }

    }

    return -1;

}

static void *dl_globallookup(const char *name)

{

    void *ret;

    shl_t h = NULL;

    return shl_findsym(&h, name, TYPE_UNDEFINED, &ret) ? NULL : ret;

}

#endif                          /* DSO_DL */