/*

 * Copyright 1995-2019 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 "e_os.h"

#include "internal/cryptlib.h"

#include <stdio.h>

#include <time.h>

#include <errno.h>

#include <sys/types.h>

#ifndef OPENSSL_NO_POSIX_IO

# include <sys/stat.h>

#endif

#include <openssl/x509.h>

#include "crypto/x509.h"

#include "x509_local.h"

struct lookup_dir_hashes_st {

    unsigned long hash;

    int suffix;

};

struct lookup_dir_entry_st {

    char *dir;

    int dir_type;

    STACK_OF(BY_DIR_HASH) *hashes;

};

typedef struct lookup_dir_st {

    BUF_MEM *buffer;

    STACK_OF(BY_DIR_ENTRY) *dirs;

    CRYPTO_RWLOCK *lock;

} BY_DIR;

static int dir_ctrl(X509_LOOKUP *ctx, int cmd, const char *argp, long argl,

                    char **ret);

static int new_dir(X509_LOOKUP *lu);

static void free_dir(X509_LOOKUP *lu);

static int add_cert_dir(BY_DIR *ctx, const char *dir, int type);

static int get_cert_by_subject(X509_LOOKUP *xl, X509_LOOKUP_TYPE type,

                               X509_NAME *name, X509_OBJECT *ret);

static X509_LOOKUP_METHOD x509_dir_lookup = {

    "Load certs from files in a directory",

    new_dir,                    /* new_item */

    free_dir,                   /* free */

    NULL,                       /* init */

    NULL,                       /* shutdown */

    dir_ctrl,                   /* ctrl */

    get_cert_by_subject,        /* get_by_subject */

    NULL,                       /* get_by_issuer_serial */

    NULL,                       /* get_by_fingerprint */

    NULL,                       /* get_by_alias */

};

X509_LOOKUP_METHOD *X509_LOOKUP_hash_dir(void)

{

    return &x509_dir_lookup;

}

static int dir_ctrl(X509_LOOKUP *ctx, int cmd, const char *argp, long argl,

                    char **retp)

{

    int ret = 0;

    BY_DIR *ld = (BY_DIR *)ctx->method_data;

    switch (cmd) {

    case X509_L_ADD_DIR:

        if (argl == X509_FILETYPE_DEFAULT) {

            const char *dir = ossl_safe_getenv(X509_get_default_cert_dir_env());

            if (dir)

                ret = add_cert_dir(ld, dir, X509_FILETYPE_PEM);

            else

                ret = add_cert_dir(ld, X509_get_default_cert_dir(),

                                   X509_FILETYPE_PEM);

            if (!ret) {

                X509err(X509_F_DIR_CTRL, X509_R_LOADING_CERT_DIR);

            }

        } else

            ret = add_cert_dir(ld, argp, (int)argl);

        break;

    }

    return ret;

}

static int new_dir(X509_LOOKUP *lu)

{

    BY_DIR *a = OPENSSL_malloc(sizeof(*a));

    if (a == NULL) {

        X509err(X509_F_NEW_DIR, ERR_R_MALLOC_FAILURE);

        return 0;

    }

    if ((a->buffer = BUF_MEM_new()) == NULL) {

        X509err(X509_F_NEW_DIR, ERR_R_MALLOC_FAILURE);

        goto err;

    }

    a->dirs = NULL;

    a->lock = CRYPTO_THREAD_lock_new();

    if (a->lock == NULL) {

        BUF_MEM_free(a->buffer);

        X509err(X509_F_NEW_DIR, ERR_R_MALLOC_FAILURE);

        goto err;

    }

    lu->method_data = a;

    return 1;

 err:

    OPENSSL_free(a);

    return 0;

}

static void by_dir_hash_free(BY_DIR_HASH *hash)

{

    OPENSSL_free(hash);

}

static int by_dir_hash_cmp(const BY_DIR_HASH *const *a,

                           const BY_DIR_HASH *const *b)

{

    if ((*a)->hash > (*b)->hash)

        return 1;

    if ((*a)->hash < (*b)->hash)

        return -1;

    return 0;

}

static void by_dir_entry_free(BY_DIR_ENTRY *ent)

{

    OPENSSL_free(ent->dir);

    sk_BY_DIR_HASH_pop_free(ent->hashes, by_dir_hash_free);

    OPENSSL_free(ent);

}

static void free_dir(X509_LOOKUP *lu)

{

    BY_DIR *a = (BY_DIR *)lu->method_data;

    sk_BY_DIR_ENTRY_pop_free(a->dirs, by_dir_entry_free);

    BUF_MEM_free(a->buffer);

    CRYPTO_THREAD_lock_free(a->lock);

    OPENSSL_free(a);

}

static int add_cert_dir(BY_DIR *ctx, const char *dir, int type)

{

    int j;

    size_t len;

    const char *s, *ss, *p;

    if (dir == NULL || !*dir) {

        X509err(X509_F_ADD_CERT_DIR, X509_R_INVALID_DIRECTORY);

        return 0;

    }

    s = dir;

    p = s;

    do {

        if ((*p == LIST_SEPARATOR_CHAR) || (*p == '\0')) {

            BY_DIR_ENTRY *ent;

            ss = s;

            s = p + 1;

            len = p - ss;

            if (len == 0)

                continue;

            for (j = 0; j < sk_BY_DIR_ENTRY_num(ctx->dirs); j++) {

                ent = sk_BY_DIR_ENTRY_value(ctx->dirs, j);

                if (strlen(ent->dir) == len && strncmp(ent->dir, ss, len) == 0)

                    break;

            }

            if (j < sk_BY_DIR_ENTRY_num(ctx->dirs))

                continue;

            if (ctx->dirs == NULL) {

                ctx->dirs = sk_BY_DIR_ENTRY_new_null();

                if (!ctx->dirs) {

                    X509err(X509_F_ADD_CERT_DIR, ERR_R_MALLOC_FAILURE);

                    return 0;

                }

            }

            ent = OPENSSL_malloc(sizeof(*ent));

            if (ent == NULL) {

                X509err(X509_F_ADD_CERT_DIR, ERR_R_MALLOC_FAILURE);

                return 0;

            }

            ent->dir_type = type;

            ent->hashes = sk_BY_DIR_HASH_new(by_dir_hash_cmp);

            ent->dir = OPENSSL_strndup(ss, len);

            if (ent->dir == NULL || ent->hashes == NULL) {

                by_dir_entry_free(ent);

                return 0;

            }

            if (!sk_BY_DIR_ENTRY_push(ctx->dirs, ent)) {

                by_dir_entry_free(ent);

                X509err(X509_F_ADD_CERT_DIR, ERR_R_MALLOC_FAILURE);

                return 0;

            }

        }

    } while (*p++ != '\0');

    return 1;

}

static int get_cert_by_subject(X509_LOOKUP *xl, X509_LOOKUP_TYPE type,

                               X509_NAME *name, X509_OBJECT *ret)

{

    BY_DIR *ctx;

    union {

        X509 st_x509;

        X509_CRL crl;

    } data;

    int ok = 0;

    int i, j, k;

    unsigned long h;

    BUF_MEM *b = NULL;

    X509_OBJECT stmp, *tmp;

    const char *postfix = "";

    if (name == NULL)

        return 0;

    stmp.type = type;

    if (type == X509_LU_X509) {

        data.st_x509.cert_info.subject = name;

        stmp.data.x509 = &data.st_x509;

        postfix = "";

    } else if (type == X509_LU_CRL) {

        data.crl.crl.issuer = name;

        stmp.data.crl = &data.crl;

        postfix = "r";

    } else {

        X509err(X509_F_GET_CERT_BY_SUBJECT, X509_R_WRONG_LOOKUP_TYPE);

        goto finish;

    }

    if ((b = BUF_MEM_new()) == NULL) {

        X509err(X509_F_GET_CERT_BY_SUBJECT, ERR_R_BUF_LIB);

        goto finish;

    }

    ctx = (BY_DIR *)xl->method_data;

    h = X509_NAME_hash(name);

    for (i = 0; i < sk_BY_DIR_ENTRY_num(ctx->dirs); i++) {

        BY_DIR_ENTRY *ent;

        int idx;

        BY_DIR_HASH htmp, *hent;

        ent = sk_BY_DIR_ENTRY_value(ctx->dirs, i);

        j = strlen(ent->dir) + 1 + 8 + 6 + 1 + 1;

        if (!BUF_MEM_grow(b, j)) {

            X509err(X509_F_GET_CERT_BY_SUBJECT, ERR_R_MALLOC_FAILURE);

            goto finish;

        }

        if (type == X509_LU_CRL && ent->hashes) {

            htmp.hash = h;

            CRYPTO_THREAD_read_lock(ctx->lock);

            idx = sk_BY_DIR_HASH_find(ent->hashes, &htmp);

            if (idx >= 0) {

                hent = sk_BY_DIR_HASH_value(ent->hashes, idx);

                k = hent->suffix;

            } else {

                hent = NULL;

                k = 0;

            }

            CRYPTO_THREAD_unlock(ctx->lock);

        } else {

            k = 0;

            hent = NULL;

        }

        for (;;) {

            char c = '/';

#ifdef OPENSSL_SYS_VMS

            c = ent->dir[strlen(ent->dir) - 1];

            if (c != ':' && c != '>' && c != ']') {

                /*

                 * If no separator is present, we assume the directory

                 * specifier is a logical name, and add a colon.  We really

                 * should use better VMS routines for merging things like

                 * this, but this will do for now... -- Richard Levitte

                 */

                c = ':';

            } else {

                c = '\0';

            }

#endif

            if (c == '\0') {

                /*

                 * This is special.  When c == '\0', no directory separator

                 * should be added.

                 */

                BIO_snprintf(b->data, b->max,

                             "%s%08lx.%s%d", ent->dir, h, postfix, k);

            } else {

                BIO_snprintf(b->data, b->max,

                             "%s%c%08lx.%s%d", ent->dir, c, h, postfix, k);

            }

#ifndef OPENSSL_NO_POSIX_IO

# ifdef _WIN32

#  define stat _stat

# endif

            {

                struct stat st;

                if (stat(b->data, &st) < 0)

                    break;

            }

#endif

            /* found one. */

            if (type == X509_LU_X509) {

                if ((X509_load_cert_file(xl, b->data, ent->dir_type)) == 0)

                    break;

            } else if (type == X509_LU_CRL) {

                if ((X509_load_crl_file(xl, b->data, ent->dir_type)) == 0)

                    break;

            }

            /* else case will caught higher up */

            k++;

        }

        /*

         * we have added it to the cache so now pull it out again

         */

        X509_STORE_lock(xl->store_ctx);

        j = sk_X509_OBJECT_find(xl->store_ctx->objs, &stmp);

        tmp = sk_X509_OBJECT_value(xl->store_ctx->objs, j);

        X509_STORE_unlock(xl->store_ctx);

        /* If a CRL, update the last file suffix added for this */

        if (type == X509_LU_CRL) {

            CRYPTO_THREAD_write_lock(ctx->lock);

            /*

             * Look for entry again in case another thread added an entry

             * first.

             */

            if (hent == NULL) {

                htmp.hash = h;

                idx = sk_BY_DIR_HASH_find(ent->hashes, &htmp);

                hent = sk_BY_DIR_HASH_value(ent->hashes, idx);

            }

            if (hent == NULL) {

                hent = OPENSSL_malloc(sizeof(*hent));

                if (hent == NULL) {

                    CRYPTO_THREAD_unlock(ctx->lock);

                    X509err(X509_F_GET_CERT_BY_SUBJECT, ERR_R_MALLOC_FAILURE);

                    ok = 0;

                    goto finish;

                }

                hent->hash = h;

                hent->suffix = k;

                if (!sk_BY_DIR_HASH_push(ent->hashes, hent)) {

                    CRYPTO_THREAD_unlock(ctx->lock);

                    OPENSSL_free(hent);

                    X509err(X509_F_GET_CERT_BY_SUBJECT, ERR_R_MALLOC_FAILURE);

                    ok = 0;

                    goto finish;

                }

            } else if (hent->suffix < k) {

                hent->suffix = k;

            }

            CRYPTO_THREAD_unlock(ctx->lock);

        }

        if (tmp != NULL) {

            ok = 1;

            ret->type = tmp->type;

            memcpy(&ret->data, &tmp->data, sizeof(ret->data));

            /*

             * Clear any errors that might have been raised processing empty

             * or malformed files.

             */

            ERR_clear_error();

            goto finish;

        }

    }

 finish:

    BUF_MEM_free(b);

    return ok;

}