965 lines
24 KiB
C
965 lines
24 KiB
C
/*
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* Asterisk -- An open source telephony toolkit.
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*
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* Copyright (C) 1999 - 2006, Digium, Inc.
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*
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* Mark Spencer <markster@digium.com>
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*
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* See http://www.asterisk.org for more information about
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* the Asterisk project. Please do not directly contact
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* any of the maintainers of this project for assistance;
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* the project provides a web site, mailing lists and IRC
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* channels for your use.
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*
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* This program is free software, distributed under the terms of
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* the GNU General Public License Version 2. See the LICENSE file
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* at the top of the source tree.
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*/
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/*! \file
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*
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* \brief Provide Cryptographic Signature capability
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*
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* \author Mark Spencer <markster@digium.com>
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*
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* Uses the OpenSSL library, available at
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* http://www.openssl.org/
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*/
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/*** MODULEINFO
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<depend>openssl</depend>
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<support_level>core</support_level>
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***/
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#include "asterisk.h"
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#include <dirent.h> /* for closedir, opendir, readdir, DIR */
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#include <openssl/err.h> /* for ERR_print_errors_fp */
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#include <openssl/ssl.h> /* for NID_sha1, RSA */
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#include <openssl/evp.h> /* for EVP_PKEY, EVP_sha1(), ... */
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#include <openssl/md5.h> /* for MD5_DIGEST_LENGTH */
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#include <openssl/sha.h> /* for SHA_DIGEST_LENGTH */
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#include "asterisk/cli.h" /* for ast_cli, ast_cli_args, ast_cli_entry */
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#include "asterisk/compat.h" /* for strcasecmp */
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#include "asterisk/io.h" /* for ast_hide_password, ast_restore_tty */
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#include "asterisk/linkedlists.h" /* for AST_RWLIST_TRAVERSE, AST_RWLIST_U... */
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#include "asterisk/logger.h" /* for ast_log, LOG_WARNING, LOG_NOTICE */
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#include "asterisk/md5.h" /* for MD5Final, MD5Init, MD5Update, MD5... */
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#include "asterisk/module.h" /* for ast_module_flags::AST_MODFLAG_GLO... */
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#include "asterisk/options.h" /* for ast_opt_init_keys */
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#include "asterisk/paths.h" /* for ast_config_AST_KEY_DIR */
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#include "asterisk/utils.h" /* for ast_copy_string, ast_base64decode */
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#define AST_API_MODULE
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#include "asterisk/crypto.h" /* for AST_KEY_PUBLIC, AST_KEY_PRIVATE */
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/*
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* Asterisk uses RSA keys with SHA-1 message digests for its
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* digital signatures. The choice of RSA is due to its higher
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* throughput on verification, and the choice of SHA-1 based
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* on the recently discovered collisions in MD5's compression
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* algorithm and recommendations of avoiding MD5 in new schemes
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* from various industry experts.
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*
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* We use OpenSSL to provide our crypto routines, although we never
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* actually use full-up SSL
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*
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*/
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#define KEY_NEEDS_PASSCODE (1 << 16)
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/* From RFC-2437, section 9.1.1 the padding size is 1+2*hLen, where
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* the hLen for SHA-1 is 20 bytes (or 160 bits).
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*/
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#define RSA_PKCS1_OAEP_PADDING_SIZE (1 + 2 * SHA_DIGEST_LENGTH)
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struct ast_key {
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/*! Name of entity */
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char name[80];
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/*! File name */
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char fn[256];
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/*! Key type (AST_KEY_PUB or AST_KEY_PRIV, along with flags from above) */
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int ktype;
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/*! RSA key structure (if successfully loaded) */
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EVP_PKEY *pkey;
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/*! Whether we should be deleted */
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int delme;
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/*! FD for input (or -1 if no input allowed, or -2 if we needed input) */
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int infd;
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/*! FD for output */
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int outfd;
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/*! Last MD5 Digest */
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unsigned char digest[MD5_DIGEST_LENGTH];
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AST_RWLIST_ENTRY(ast_key) list;
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};
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static AST_RWLIST_HEAD_STATIC(keys, ast_key);
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static void crypto_load(int ifd, int ofd);
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/*!
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* \brief setting of priv key
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* \param buf
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* \param size
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* \param rwflag
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* \param userdata
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* \return length of string,-1 on failure
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*/
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static int pw_cb(char *buf, int size, int rwflag, void *userdata)
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{
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struct ast_key *key = (struct ast_key *)userdata;
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char prompt[256];
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int tmp;
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int res;
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if (key->infd < 0) {
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/* Note that we were at least called */
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key->infd = -2;
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return -1;
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}
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snprintf(prompt, sizeof(prompt), ">>>> passcode for %s key '%s': ",
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key->ktype == AST_KEY_PRIVATE ? "PRIVATE" : "PUBLIC", key->name);
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if (write(key->outfd, prompt, strlen(prompt)) < 0) {
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ast_log(LOG_WARNING, "write() failed: %s\n", strerror(errno));
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key->infd = -2;
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return -1;
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}
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tmp = ast_hide_password(key->infd);
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memset(buf, 0, size);
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res = read(key->infd, buf, size);
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if (res == -1) {
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ast_log(LOG_WARNING, "read() failed: %s\n", strerror(errno));
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}
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ast_restore_tty(key->infd, tmp);
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if (buf[strlen(buf) -1] == '\n') {
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buf[strlen(buf) - 1] = '\0';
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}
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return strlen(buf);
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}
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/*!
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* \brief return the ast_key structure for name
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* \see ast_key_get
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*/
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struct ast_key * AST_OPTIONAL_API_NAME(ast_key_get)(const char *kname, int ktype)
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{
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struct ast_key *key;
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AST_RWLIST_RDLOCK(&keys);
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AST_RWLIST_TRAVERSE(&keys, key, list) {
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if (!strcmp(kname, key->name) &&
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(ktype == key->ktype)) {
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break;
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}
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}
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AST_RWLIST_UNLOCK(&keys);
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return key;
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}
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/*!
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* \brief load RSA key from file
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* \param dir directory string
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* \param fname name of file
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* \param ifd incoming file descriptor
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* \param ofd outgoing file descriptor
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* \param not2
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* \return key on success.
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* \retval NULL on failure.
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*/
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static struct ast_key *try_load_key(const char *dir, const char *fname, int ifd, int ofd, int *not2)
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{
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int ktype = 0, found = 0;
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char *c = NULL, ffname[256];
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unsigned char digest[MD5_DIGEST_LENGTH];
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unsigned digestlen;
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FILE *f;
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EVP_MD_CTX *ctx = NULL;
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struct ast_key *key;
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static int notice = 0;
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/* Make sure its name is a public or private key */
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if ((c = strstr(fname, ".pub")) && !strcmp(c, ".pub")) {
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ktype = AST_KEY_PUBLIC;
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} else if ((c = strstr(fname, ".key")) && !strcmp(c, ".key")) {
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ktype = AST_KEY_PRIVATE;
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} else {
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return NULL;
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}
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/* Get actual filename */
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snprintf(ffname, sizeof(ffname), "%s/%s", dir, fname);
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/* Open file */
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if (!(f = fopen(ffname, "r"))) {
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ast_log(LOG_WARNING, "Unable to open key file %s: %s\n", ffname, strerror(errno));
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return NULL;
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}
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ctx = EVP_MD_CTX_create();
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if (ctx == NULL) {
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ast_log(LOG_ERROR, "Out of memory\n");
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fclose(f);
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return NULL;
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}
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EVP_DigestInit(ctx, EVP_md5());
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while (!feof(f)) {
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/* Calculate a "whatever" quality md5sum of the key */
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char buf[256] = "";
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if (!fgets(buf, sizeof(buf), f)) {
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continue;
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}
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if (!feof(f)) {
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EVP_DigestUpdate(ctx, (unsigned char *)buf, strlen(buf));
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}
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}
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EVP_DigestFinal(ctx, digest, &digestlen);
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EVP_MD_CTX_destroy(ctx);
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/* Look for an existing key */
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AST_RWLIST_TRAVERSE(&keys, key, list) {
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if (!strcasecmp(key->fn, ffname)) {
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break;
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}
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}
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if (key) {
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/* If the MD5 sum is the same, and it isn't awaiting a passcode
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then this is far enough */
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if (!memcmp(digest, key->digest, sizeof(digest)) &&
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!(key->ktype & KEY_NEEDS_PASSCODE)) {
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fclose(f);
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key->delme = 0;
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return NULL;
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} else {
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/* Preserve keytype */
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ktype = key->ktype;
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/* Recycle the same structure */
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found++;
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}
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}
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/* Make fname just be the normal name now */
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*c = '\0';
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if (!key) {
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if (!(key = ast_calloc(1, sizeof(*key)))) {
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fclose(f);
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return NULL;
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}
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}
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/* First the filename */
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ast_copy_string(key->fn, ffname, sizeof(key->fn));
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/* Then the name */
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ast_copy_string(key->name, fname, sizeof(key->name));
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key->ktype = ktype;
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/* Yes, assume we're going to be deleted */
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key->delme = 1;
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/* Keep the key type */
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memcpy(key->digest, digest, sizeof(key->digest));
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/* Can I/O takes the FD we're given */
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key->infd = ifd;
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key->outfd = ofd;
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/* Reset the file back to the beginning */
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rewind(f);
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/* Now load the key with the right method */
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if (ktype == AST_KEY_PUBLIC) {
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PEM_read_PUBKEY(f, &key->pkey, pw_cb, key);
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} else {
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PEM_read_PrivateKey(f, &key->pkey, pw_cb, key);
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}
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fclose(f);
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if (key->pkey) {
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if (EVP_PKEY_size(key->pkey) == (AST_CRYPTO_RSA_KEY_BITS / 8)) {
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/* Key loaded okay */
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key->ktype &= ~KEY_NEEDS_PASSCODE;
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ast_verb(3, "Loaded %s key '%s'\n", key->ktype == AST_KEY_PUBLIC ? "PUBLIC" : "PRIVATE", key->name);
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ast_debug(1, "Key '%s' loaded OK\n", key->name);
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key->delme = 0;
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} else {
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ast_log(LOG_NOTICE, "Key '%s' is not expected size.\n", key->name);
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}
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} else if (key->infd != -2) {
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ast_log(LOG_WARNING, "Key load %s '%s' failed\n", key->ktype == AST_KEY_PUBLIC ? "PUBLIC" : "PRIVATE", key->name);
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if (ofd > -1) {
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ERR_print_errors_fp(stderr);
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} else {
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ERR_print_errors_fp(stderr);
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}
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} else {
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ast_log(LOG_NOTICE, "Key '%s' needs passcode.\n", key->name);
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key->ktype |= KEY_NEEDS_PASSCODE;
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if (!notice) {
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if (!ast_opt_init_keys) {
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ast_log(LOG_NOTICE, "Add the '-i' flag to the asterisk command line if you want to automatically initialize passcodes at launch.\n");
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}
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notice++;
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}
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/* Keep it anyway */
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key->delme = 0;
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/* Print final notice about "keys init" when done */
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*not2 = 1;
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}
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/* If this is a new key add it to the list */
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if (!found) {
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AST_RWLIST_INSERT_TAIL(&keys, key, list);
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}
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return key;
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}
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static int evp_pkey_sign(EVP_PKEY *pkey, const unsigned char *in, unsigned inlen, unsigned char *sig, unsigned *siglen, unsigned padding)
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{
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EVP_PKEY_CTX *ctx = NULL;
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int res = -1;
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size_t _siglen;
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if (*siglen < EVP_PKEY_size(pkey)) {
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return -1;
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}
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if ((ctx = EVP_PKEY_CTX_new(pkey, NULL)) == NULL) {
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return -1;
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}
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do {
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if ((res = EVP_PKEY_sign_init(ctx)) <= 0) {
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break;
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}
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if ((res = EVP_PKEY_CTX_set_rsa_padding(ctx, padding)) <= 0) {
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break;
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}
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if ((res = EVP_PKEY_CTX_set_signature_md(ctx, EVP_sha1())) <= 0) {
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break;
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}
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_siglen = *siglen;
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if ((res = EVP_PKEY_sign(ctx, sig, &_siglen, in, inlen)) <= 0) {
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break;
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}
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*siglen = _siglen;
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} while (0);
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EVP_PKEY_CTX_free(ctx);
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return res;
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}
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/*!
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* \brief signs outgoing message with public key
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* \see ast_sign_bin
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*/
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int AST_OPTIONAL_API_NAME(ast_sign_bin)(struct ast_key *key, const char *msg, int msglen, unsigned char *dsig)
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{
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unsigned char digest[SHA_DIGEST_LENGTH];
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unsigned digestlen, siglen = 128;
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int res;
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EVP_MD_CTX *ctx = NULL;
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if (key->ktype != AST_KEY_PRIVATE) {
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ast_log(LOG_WARNING, "Cannot sign with a public key\n");
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return -1;
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}
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if (siglen < EVP_PKEY_size(key->pkey)) {
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ast_log(LOG_WARNING, "Signature buffer too small\n");
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return -1;
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}
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/* Calculate digest of message */
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ctx = EVP_MD_CTX_create();
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if (ctx == NULL) {
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ast_log(LOG_ERROR, "Out of memory\n");
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return -1;
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}
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EVP_DigestInit(ctx, EVP_sha1());
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EVP_DigestUpdate(ctx, msg, msglen);
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EVP_DigestFinal(ctx, digest, &digestlen);
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EVP_MD_CTX_destroy(ctx);
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/* Verify signature */
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if ((res = evp_pkey_sign(key->pkey, digest, sizeof(digest), dsig, &siglen, RSA_PKCS1_PADDING)) <= 0) {
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ast_log(LOG_WARNING, "RSA Signature (key %s) failed %d\n", key->name, res);
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return -1;
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}
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if (siglen != EVP_PKEY_size(key->pkey)) {
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ast_log(LOG_WARNING, "Unexpected signature length %u, expecting %d\n", siglen, EVP_PKEY_size(key->pkey));
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return -1;
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}
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return 0;
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}
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static int evp_pkey_decrypt(EVP_PKEY *pkey, const unsigned char *in, unsigned inlen, unsigned char *out, unsigned *outlen, unsigned padding)
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{
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EVP_PKEY_CTX *ctx = NULL;
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int res = -1;
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size_t _outlen;
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if (*outlen < EVP_PKEY_size(pkey)) {
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return -1;
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}
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if (inlen != EVP_PKEY_size(pkey)) {
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return -1;
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}
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if ((ctx = EVP_PKEY_CTX_new(pkey, NULL)) == NULL) {
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return -1;
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}
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do {
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if ((res = EVP_PKEY_decrypt_init(ctx)) <= 0) {
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break;
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}
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if ((res = EVP_PKEY_CTX_set_rsa_padding(ctx, padding)) <= 0) {
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break;
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}
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_outlen = *outlen;
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if ((res = EVP_PKEY_decrypt(ctx, out, &_outlen, in, inlen)) <= 0) {
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break;
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}
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res = *outlen = _outlen;
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} while (0);
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EVP_PKEY_CTX_free(ctx);
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return res;
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}
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|
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/*!
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* \brief decrypt a message
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* \see ast_decrypt_bin
|
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*/
|
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int AST_OPTIONAL_API_NAME(ast_decrypt_bin)(unsigned char *dst, const unsigned char *src, int srclen, struct ast_key *key)
|
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{
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int res;
|
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unsigned pos = 0, dstlen, blocksize;
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|
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if (key->ktype != AST_KEY_PRIVATE) {
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ast_log(LOG_WARNING, "Cannot decrypt with a public key\n");
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return -1;
|
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}
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|
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blocksize = EVP_PKEY_size(key->pkey);
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|
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if (srclen % blocksize) {
|
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ast_log(LOG_NOTICE, "Tried to decrypt something not a multiple of %u bytes\n", blocksize);
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return -1;
|
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}
|
|
|
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while (srclen > 0) {
|
|
/* Process chunks 128 bytes at a time */
|
|
dstlen = blocksize;
|
|
if ((res = evp_pkey_decrypt(key->pkey, src, blocksize, dst, &dstlen, RSA_PKCS1_OAEP_PADDING)) <= 0) {
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return -1;
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}
|
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pos += dstlen;
|
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src += blocksize;
|
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srclen -= blocksize;
|
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dst += dstlen;
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}
|
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|
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return pos;
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}
|
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|
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static int evp_pkey_encrypt(EVP_PKEY *pkey, const unsigned char *in, unsigned inlen, unsigned char *out, unsigned *outlen, unsigned padding)
|
|
{
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EVP_PKEY_CTX *ctx = NULL;
|
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int res = -1;
|
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size_t _outlen;
|
|
|
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if (padding != RSA_PKCS1_OAEP_PADDING) {
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ast_log(LOG_WARNING, "Only OAEP padding is supported for now\n");
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return -1;
|
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}
|
|
|
|
if (inlen > EVP_PKEY_size(pkey) - RSA_PKCS1_OAEP_PADDING_SIZE) {
|
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return -1;
|
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}
|
|
|
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if (*outlen < EVP_PKEY_size(pkey)) {
|
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return -1;
|
|
}
|
|
|
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do {
|
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if ((ctx = EVP_PKEY_CTX_new(pkey, NULL)) == NULL) {
|
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break;
|
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}
|
|
|
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if ((res = EVP_PKEY_encrypt_init(ctx)) <= 0) {
|
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break;
|
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}
|
|
if ((res = EVP_PKEY_CTX_set_rsa_padding(ctx, padding)) <= 0) {
|
|
break;
|
|
}
|
|
_outlen = *outlen;
|
|
if ((res = EVP_PKEY_encrypt(ctx, out, &_outlen, in, inlen)) <= 0) {
|
|
break;
|
|
}
|
|
res = *outlen = _outlen;
|
|
} while (0);
|
|
|
|
EVP_PKEY_CTX_free(ctx);
|
|
return res;
|
|
}
|
|
|
|
/*!
|
|
* \brief encrypt a message
|
|
* \see ast_encrypt_bin
|
|
*/
|
|
int AST_OPTIONAL_API_NAME(ast_encrypt_bin)(unsigned char *dst, const unsigned char *src, int srclen, struct ast_key *key)
|
|
{
|
|
unsigned bytes, pos = 0, dstlen, blocksize;
|
|
int res;
|
|
|
|
if (key->ktype != AST_KEY_PUBLIC) {
|
|
ast_log(LOG_WARNING, "Cannot encrypt with a private key\n");
|
|
return -1;
|
|
}
|
|
|
|
blocksize = EVP_PKEY_size(key->pkey);
|
|
|
|
while (srclen) {
|
|
bytes = srclen;
|
|
if (bytes > blocksize - RSA_PKCS1_OAEP_PADDING_SIZE) {
|
|
bytes = blocksize - RSA_PKCS1_OAEP_PADDING_SIZE;
|
|
}
|
|
/* Process chunks 128-41 bytes at a time */
|
|
dstlen = blocksize;
|
|
if ((res = evp_pkey_encrypt(key->pkey, src, bytes, dst, &dstlen, RSA_PKCS1_OAEP_PADDING)) != blocksize) {
|
|
ast_log(LOG_NOTICE, "How odd, encrypted size is %d\n", res);
|
|
return -1;
|
|
}
|
|
src += bytes;
|
|
srclen -= bytes;
|
|
pos += dstlen;
|
|
dst += dstlen;
|
|
}
|
|
return pos;
|
|
}
|
|
|
|
/*!
|
|
* \brief wrapper for __ast_sign_bin then base64 encode it
|
|
* \see ast_sign
|
|
*/
|
|
int AST_OPTIONAL_API_NAME(ast_sign)(struct ast_key *key, char *msg, char *sig)
|
|
{
|
|
/* assumes 1024 bit RSA key size */
|
|
unsigned char dsig[128];
|
|
int siglen = sizeof(dsig), res;
|
|
|
|
if (!(res = ast_sign_bin(key, msg, strlen(msg), dsig))) {
|
|
/* Success -- encode (256 bytes max as documented) */
|
|
ast_base64encode(sig, dsig, siglen, 256);
|
|
}
|
|
|
|
return res;
|
|
}
|
|
|
|
static int evp_pkey_verify(EVP_PKEY *pkey, const unsigned char *in, unsigned inlen, const unsigned char *sig, unsigned siglen, unsigned padding)
|
|
{
|
|
EVP_PKEY_CTX *ctx = NULL;
|
|
int res = -1;
|
|
|
|
if (siglen < EVP_PKEY_size(pkey)) {
|
|
return -1;
|
|
}
|
|
|
|
if ((ctx = EVP_PKEY_CTX_new(pkey, NULL)) == NULL) {
|
|
return -1;
|
|
}
|
|
|
|
do {
|
|
if ((res = EVP_PKEY_verify_init(ctx)) <= 0) {
|
|
break;
|
|
}
|
|
if ((res = EVP_PKEY_CTX_set_rsa_padding(ctx, padding)) <= 0) {
|
|
break;
|
|
}
|
|
if ((res = EVP_PKEY_CTX_set_signature_md(ctx, EVP_sha1())) <= 0) {
|
|
break;
|
|
}
|
|
if ((res = EVP_PKEY_verify(ctx, sig, siglen, in, inlen)) <= 0) {
|
|
break;
|
|
}
|
|
} while (0);
|
|
|
|
EVP_PKEY_CTX_free(ctx);
|
|
return res;
|
|
}
|
|
|
|
/*!
|
|
* \brief check signature of a message
|
|
* \see ast_check_signature_bin
|
|
*/
|
|
int AST_OPTIONAL_API_NAME(ast_check_signature_bin)(struct ast_key *key, const char *msg, int msglen, const unsigned char *dsig)
|
|
{
|
|
unsigned char digest[SHA_DIGEST_LENGTH];
|
|
unsigned digestlen;
|
|
int res;
|
|
EVP_MD_CTX *ctx = NULL;
|
|
|
|
if (key->ktype != AST_KEY_PUBLIC) {
|
|
/* Okay, so of course you really *can* but for our purposes
|
|
we're going to say you can't */
|
|
ast_log(LOG_WARNING, "Cannot check message signature with a private key\n");
|
|
return -1;
|
|
}
|
|
|
|
/* Calculate digest of message */
|
|
ctx = EVP_MD_CTX_create();
|
|
if (ctx == NULL) {
|
|
ast_log(LOG_ERROR, "Out of memory\n");
|
|
return -1;
|
|
}
|
|
EVP_DigestInit(ctx, EVP_sha1());
|
|
EVP_DigestUpdate(ctx, msg, msglen);
|
|
EVP_DigestFinal(ctx, digest, &digestlen);
|
|
EVP_MD_CTX_destroy(ctx);
|
|
|
|
/* Verify signature */
|
|
if (!(res = evp_pkey_verify(key->pkey, (const unsigned char *)digest, sizeof(digest), (unsigned char *)dsig, 128, RSA_PKCS1_PADDING))) {
|
|
ast_debug(1, "Key failed verification: %s\n", key->name);
|
|
return -1;
|
|
}
|
|
|
|
/* Pass */
|
|
return 0;
|
|
}
|
|
|
|
/*!
|
|
* \brief base64 decode then sent to __ast_check_signature_bin
|
|
* \see ast_check_signature
|
|
*/
|
|
int AST_OPTIONAL_API_NAME(ast_check_signature)(struct ast_key *key, const char *msg, const char *sig)
|
|
{
|
|
unsigned char dsig[128];
|
|
int res;
|
|
|
|
/* Decode signature */
|
|
if ((res = ast_base64decode(dsig, sig, sizeof(dsig))) != sizeof(dsig)) {
|
|
ast_log(LOG_WARNING, "Signature improper length (expect %d, got %d)\n", (int)sizeof(dsig), (int)res);
|
|
return -1;
|
|
}
|
|
|
|
res = ast_check_signature_bin(key, msg, strlen(msg), dsig);
|
|
|
|
return res;
|
|
}
|
|
|
|
int AST_OPTIONAL_API_NAME(ast_crypto_loaded)(void)
|
|
{
|
|
return 1;
|
|
}
|
|
|
|
int AST_OPTIONAL_API_NAME(ast_crypto_reload)(void)
|
|
{
|
|
crypto_load(-1, -1);
|
|
return 1;
|
|
}
|
|
|
|
int AST_OPTIONAL_API_NAME(ast_aes_set_encrypt_key)(const unsigned char *key, ast_aes_encrypt_key *ctx)
|
|
{
|
|
if (key == NULL || ctx == NULL) {
|
|
return -1;
|
|
}
|
|
memcpy(ctx->raw, key, AST_CRYPTO_AES_BLOCKSIZE / 8);
|
|
return 0;
|
|
}
|
|
|
|
int AST_OPTIONAL_API_NAME(ast_aes_set_decrypt_key)(const unsigned char *key, ast_aes_decrypt_key *ctx)
|
|
{
|
|
if (key == NULL || ctx == NULL) {
|
|
return -1;
|
|
}
|
|
memcpy(ctx->raw, key, AST_CRYPTO_AES_BLOCKSIZE / 8);
|
|
return 0;
|
|
}
|
|
|
|
static int evp_cipher_aes_encrypt(const unsigned char *in, unsigned char *out, unsigned inlen, const ast_aes_encrypt_key *key)
|
|
{
|
|
EVP_CIPHER_CTX *ctx = NULL;
|
|
int res, outlen, finallen;
|
|
unsigned char final[AST_CRYPTO_AES_BLOCKSIZE / 8];
|
|
|
|
if ((ctx = EVP_CIPHER_CTX_new()) == NULL) {
|
|
return -1;
|
|
}
|
|
|
|
do {
|
|
if ((res = EVP_CipherInit(ctx, EVP_aes_128_ecb(), key->raw, NULL, 1)) <= 0) {
|
|
break;
|
|
}
|
|
EVP_CIPHER_CTX_set_padding(ctx, 0);
|
|
if ((res = EVP_CipherUpdate(ctx, out, &outlen, in, inlen)) <= 0) {
|
|
break;
|
|
}
|
|
/* for ECB, this is a no-op */
|
|
if ((res = EVP_CipherFinal(ctx, final, &finallen)) <= 0) {
|
|
break;
|
|
}
|
|
|
|
res = outlen;
|
|
} while (0);
|
|
|
|
EVP_CIPHER_CTX_free(ctx);
|
|
|
|
return res;
|
|
}
|
|
|
|
int AST_OPTIONAL_API_NAME(ast_aes_encrypt)(const unsigned char *in, unsigned char *out, const ast_aes_encrypt_key *key)
|
|
{
|
|
int res;
|
|
|
|
if ((res = evp_cipher_aes_encrypt(in, out, AST_CRYPTO_AES_BLOCKSIZE / 8, key)) <= 0) {
|
|
ast_log(LOG_ERROR, "AES encryption failed\n");
|
|
}
|
|
return res;
|
|
}
|
|
|
|
static int evp_cipher_aes_decrypt(const unsigned char *in, unsigned char *out, unsigned inlen, const ast_aes_decrypt_key *key)
|
|
{
|
|
EVP_CIPHER_CTX *ctx = NULL;
|
|
int res, outlen, finallen;
|
|
unsigned char final[AST_CRYPTO_AES_BLOCKSIZE / 8];
|
|
|
|
if ((ctx = EVP_CIPHER_CTX_new()) == NULL) {
|
|
return -1;
|
|
}
|
|
|
|
do {
|
|
if ((res = EVP_CipherInit(ctx, EVP_aes_128_ecb(), key->raw, NULL, 0)) <= 0) {
|
|
break;
|
|
}
|
|
EVP_CIPHER_CTX_set_padding(ctx, 0);
|
|
if ((res = EVP_CipherUpdate(ctx, out, &outlen, in, inlen)) <= 0) {
|
|
break;
|
|
}
|
|
/* for ECB, this is a no-op */
|
|
if ((res = EVP_CipherFinal(ctx, final, &finallen)) <= 0) {
|
|
break;
|
|
}
|
|
|
|
res = outlen;
|
|
} while (0);
|
|
|
|
EVP_CIPHER_CTX_free(ctx);
|
|
|
|
return res;
|
|
}
|
|
|
|
int AST_OPTIONAL_API_NAME(ast_aes_decrypt)(const unsigned char *in, unsigned char *out, const ast_aes_decrypt_key *key)
|
|
{
|
|
int res;
|
|
|
|
if ((res = evp_cipher_aes_decrypt(in, out, AST_CRYPTO_AES_BLOCKSIZE / 8, key)) <= 0) {
|
|
ast_log(LOG_ERROR, "AES decryption failed\n");
|
|
}
|
|
return res;
|
|
}
|
|
|
|
/*!
|
|
* \brief refresh RSA keys from file
|
|
* \param ifd file descriptor
|
|
* \param ofd file descriptor
|
|
*/
|
|
static void crypto_load(int ifd, int ofd)
|
|
{
|
|
struct ast_key *key;
|
|
DIR *dir = NULL;
|
|
struct dirent *ent;
|
|
int note = 0;
|
|
|
|
AST_RWLIST_WRLOCK(&keys);
|
|
|
|
/* Mark all keys for deletion */
|
|
AST_RWLIST_TRAVERSE(&keys, key, list) {
|
|
key->delme = 1;
|
|
}
|
|
|
|
/* Load new keys */
|
|
if ((dir = opendir(ast_config_AST_KEY_DIR))) {
|
|
while ((ent = readdir(dir))) {
|
|
if (!strcmp(ent->d_name, ".") || !strcmp(ent->d_name, "..")) {
|
|
continue;
|
|
}
|
|
if (ent->d_type == DT_DIR) {
|
|
continue;
|
|
}
|
|
if (ent->d_type != DT_REG) {
|
|
ast_log(LOG_WARNING, "Non-regular file '%s' in keys directory\n", ent->d_name);
|
|
continue;
|
|
}
|
|
try_load_key(ast_config_AST_KEY_DIR, ent->d_name, ifd, ofd, ¬e);
|
|
}
|
|
closedir(dir);
|
|
} else {
|
|
ast_log(LOG_WARNING, "Unable to open key directory '%s'\n", ast_config_AST_KEY_DIR);
|
|
}
|
|
|
|
if (note) {
|
|
ast_log(LOG_NOTICE, "Please run the command 'keys init' to enter the passcodes for the keys\n");
|
|
}
|
|
|
|
/* Delete any keys that are no longer present */
|
|
AST_RWLIST_TRAVERSE_SAFE_BEGIN(&keys, key, list) {
|
|
if (key->delme) {
|
|
ast_debug(1, "Deleting key %s type %d\n", key->name, key->ktype);
|
|
AST_RWLIST_REMOVE_CURRENT(list);
|
|
if (key->pkey) {
|
|
EVP_PKEY_free(key->pkey);
|
|
}
|
|
ast_free(key);
|
|
}
|
|
}
|
|
AST_RWLIST_TRAVERSE_SAFE_END;
|
|
|
|
AST_RWLIST_UNLOCK(&keys);
|
|
}
|
|
|
|
static void md52sum(char *sum, unsigned char *md5)
|
|
{
|
|
int x;
|
|
for (x = 0; x < MD5_DIGEST_LENGTH; x++) {
|
|
sum += sprintf(sum, "%02hhx", *(md5++));
|
|
}
|
|
}
|
|
|
|
/*!
|
|
* \brief show the list of RSA keys
|
|
* \param e CLI command
|
|
* \param cmd
|
|
* \param a list of CLI arguments
|
|
* \retval CLI_SUCCESS
|
|
*/
|
|
static char *handle_cli_keys_show(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
|
|
{
|
|
#define FORMAT "%-18s %-8s %-16s %-33s\n"
|
|
|
|
struct ast_key *key;
|
|
char sum[MD5_DIGEST_LENGTH * 2 + 1];
|
|
int count_keys = 0;
|
|
|
|
switch (cmd) {
|
|
case CLI_INIT:
|
|
e->command = "keys show";
|
|
e->usage =
|
|
"Usage: keys show\n"
|
|
" Displays information about RSA keys known by Asterisk\n";
|
|
return NULL;
|
|
case CLI_GENERATE:
|
|
return NULL;
|
|
}
|
|
|
|
ast_cli(a->fd, FORMAT, "Key Name", "Type", "Status", "Sum");
|
|
ast_cli(a->fd, FORMAT, "------------------", "--------", "----------------", "--------------------------------");
|
|
|
|
AST_RWLIST_RDLOCK(&keys);
|
|
AST_RWLIST_TRAVERSE(&keys, key, list) {
|
|
md52sum(sum, key->digest);
|
|
ast_cli(a->fd, FORMAT, key->name,
|
|
(key->ktype & 0xf) == AST_KEY_PUBLIC ? "PUBLIC" : "PRIVATE",
|
|
key->ktype & KEY_NEEDS_PASSCODE ? "[Needs Passcode]" : "[Loaded]", sum);
|
|
count_keys++;
|
|
}
|
|
AST_RWLIST_UNLOCK(&keys);
|
|
|
|
ast_cli(a->fd, "\n%d known RSA keys.\n", count_keys);
|
|
|
|
return CLI_SUCCESS;
|
|
|
|
#undef FORMAT
|
|
}
|
|
|
|
/*!
|
|
* \brief initialize all RSA keys
|
|
* \param e CLI command
|
|
* \param cmd
|
|
* \param a list of CLI arguments
|
|
* \retval CLI_SUCCESS
|
|
*/
|
|
static char *handle_cli_keys_init(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
|
|
{
|
|
struct ast_key *key;
|
|
int ign;
|
|
char *kn, tmp[256] = "";
|
|
|
|
switch (cmd) {
|
|
case CLI_INIT:
|
|
e->command = "keys init";
|
|
e->usage =
|
|
"Usage: keys init\n"
|
|
" Initializes private keys (by reading in pass code from\n"
|
|
" the user)\n";
|
|
return NULL;
|
|
case CLI_GENERATE:
|
|
return NULL;
|
|
}
|
|
|
|
if (a->argc != 2) {
|
|
return CLI_SHOWUSAGE;
|
|
}
|
|
|
|
AST_RWLIST_WRLOCK(&keys);
|
|
AST_RWLIST_TRAVERSE_SAFE_BEGIN(&keys, key, list) {
|
|
/* Reload keys that need pass codes now */
|
|
if (key->ktype & KEY_NEEDS_PASSCODE) {
|
|
kn = key->fn + strlen(ast_config_AST_KEY_DIR) + 1;
|
|
ast_copy_string(tmp, kn, sizeof(tmp));
|
|
try_load_key(ast_config_AST_KEY_DIR, tmp, a->fd, a->fd, &ign);
|
|
}
|
|
}
|
|
AST_RWLIST_TRAVERSE_SAFE_END
|
|
AST_RWLIST_UNLOCK(&keys);
|
|
|
|
return CLI_SUCCESS;
|
|
}
|
|
|
|
static struct ast_cli_entry cli_crypto[] = {
|
|
AST_CLI_DEFINE(handle_cli_keys_show, "Displays RSA key information"),
|
|
AST_CLI_DEFINE(handle_cli_keys_init, "Initialize RSA key passcodes")
|
|
};
|
|
|
|
/*! \brief initialise the res_crypto module */
|
|
static int crypto_init(void)
|
|
{
|
|
ast_cli_register_multiple(cli_crypto, ARRAY_LEN(cli_crypto));
|
|
return 0;
|
|
}
|
|
|
|
static int reload(void)
|
|
{
|
|
crypto_load(-1, -1);
|
|
return 0;
|
|
}
|
|
|
|
static int load_module(void)
|
|
{
|
|
crypto_init();
|
|
if (ast_opt_init_keys) {
|
|
crypto_load(STDIN_FILENO, STDOUT_FILENO);
|
|
} else {
|
|
crypto_load(-1, -1);
|
|
}
|
|
|
|
return AST_MODULE_LOAD_SUCCESS;
|
|
}
|
|
|
|
static int unload_module(void)
|
|
{
|
|
ast_cli_unregister_multiple(cli_crypto, ARRAY_LEN(cli_crypto));
|
|
|
|
return 0;
|
|
}
|
|
|
|
AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_GLOBAL_SYMBOLS | AST_MODFLAG_LOAD_ORDER, "Cryptographic Digital Signatures",
|
|
.support_level = AST_MODULE_SUPPORT_CORE,
|
|
.load = load_module,
|
|
.unload = unload_module,
|
|
.reload = reload,
|
|
.load_pri = AST_MODPRI_CHANNEL_DEPEND, /*!< Since we don't have a config file, we could move up to REALTIME_DEPEND, if necessary */
|
|
);
|