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- /*
- * Asterisk -- An open source telephony toolkit.
- *
- * Copyright (C) 1999 - 2006, Digium, Inc.
- *
- * Mark Spencer <markster@digium.com>
- *
- * See http://www.asterisk.org for more information about
- * the Asterisk project. Please do not directly contact
- * any of the maintainers of this project for assistance;
- * the project provides a web site, mailing lists and IRC
- * channels for your use.
- *
- * This program is free software, distributed under the terms of
- * the GNU General Public License Version 2. See the LICENSE file
- * at the top of the source tree.
- */
- /*! \file
- *
- * \brief Provide Cryptographic Signature capability
- *
- * \author Mark Spencer <markster@digium.com>
- *
- * Uses the OpenSSL library, available at
- * http://www.openssl.org/
- */
- /*** MODULEINFO
- <depend>openssl</depend>
- <support_level>core</support_level>
- ***/
- #include "asterisk.h"
- #include <dirent.h> /* for closedir, opendir, readdir, DIR */
- #include <sys/stat.h> /* for fstat */
- #include <openssl/err.h> /* for ERR_print_errors_fp */
- #include <openssl/ssl.h> /* for NID_sha1, RSA */
- #include <openssl/evp.h> /* for EVP_PKEY, EVP_sha1(), ... */
- #include <openssl/md5.h> /* for MD5_DIGEST_LENGTH */
- #include <openssl/sha.h> /* for SHA_DIGEST_LENGTH */
- #include "asterisk/cli.h" /* for ast_cli, ast_cli_args, ast_cli_entry */
- #include "asterisk/compat.h" /* for strcasecmp */
- #include "asterisk/io.h" /* for ast_hide_password, ast_restore_tty */
- #include "asterisk/linkedlists.h" /* for AST_RWLIST_TRAVERSE, AST_RWLIST_U... */
- #include "asterisk/logger.h" /* for ast_log, LOG_WARNING, LOG_NOTICE */
- #include "asterisk/md5.h" /* for MD5Final, MD5Init, MD5Update, MD5... */
- #include "asterisk/module.h" /* for ast_module_flags::AST_MODFLAG_GLO... */
- #include "asterisk/options.h" /* for ast_opt_init_keys */
- #include "asterisk/paths.h" /* for ast_config_AST_KEY_DIR */
- #include "asterisk/utils.h" /* for ast_copy_string, ast_base64decode */
- #include "asterisk/file.h" /* for ast_file_read_dirs */
- #define AST_API_MODULE
- #include "asterisk/crypto.h" /* for AST_KEY_PUBLIC, AST_KEY_PRIVATE */
- /*
- * Asterisk uses RSA keys with SHA-1 message digests for its
- * digital signatures. The choice of RSA is due to its higher
- * throughput on verification, and the choice of SHA-1 based
- * on the recently discovered collisions in MD5's compression
- * algorithm and recommendations of avoiding MD5 in new schemes
- * from various industry experts.
- *
- * We use OpenSSL to provide our crypto routines, although we never
- * actually use full-up SSL
- *
- */
- #define KEY_NEEDS_PASSCODE (1 << 16)
- /* From RFC-2437, section 9.1.1 the padding size is 1+2*hLen, where
- * the hLen for SHA-1 is 20 bytes (or 160 bits).
- */
- #define RSA_PKCS1_OAEP_PADDING_SIZE (1 + 2 * SHA_DIGEST_LENGTH)
- struct ast_key {
- /*! Name of entity */
- char name[80];
- /*! File name */
- char fn[256];
- /*! Key type (AST_KEY_PUB or AST_KEY_PRIV, along with flags from above) */
- int ktype;
- /*! RSA key structure (if successfully loaded) */
- EVP_PKEY *pkey;
- /*! Whether we should be deleted */
- int delme;
- /*! FD for input (or -1 if no input allowed, or -2 if we needed input) */
- int infd;
- /*! FD for output */
- int outfd;
- /*! Last MD5 Digest */
- unsigned char digest[MD5_DIGEST_LENGTH];
- AST_RWLIST_ENTRY(ast_key) list;
- };
- static AST_RWLIST_HEAD_STATIC(keys, ast_key);
- static void crypto_load(int ifd, int ofd);
- /*!
- * \brief setting of priv key
- * \param buf
- * \param size
- * \param rwflag
- * \param userdata
- * \return length of string,-1 on failure
- */
- static int pw_cb(char *buf, int size, int rwflag, void *userdata)
- {
- struct ast_key *key = (struct ast_key *)userdata;
- char prompt[256];
- int tmp;
- int res;
- if (key->infd < 0) {
- /* Note that we were at least called */
- key->infd = -2;
- return -1;
- }
- snprintf(prompt, sizeof(prompt), ">>>> passcode for %s key '%s': ",
- key->ktype == AST_KEY_PRIVATE ? "PRIVATE" : "PUBLIC", key->name);
- if (write(key->outfd, prompt, strlen(prompt)) < 0) {
- ast_log(LOG_WARNING, "write() failed: %s\n", strerror(errno));
- key->infd = -2;
- return -1;
- }
- tmp = ast_hide_password(key->infd);
- memset(buf, 0, size);
- res = read(key->infd, buf, size);
- if (res == -1) {
- ast_log(LOG_WARNING, "read() failed: %s\n", strerror(errno));
- }
- ast_restore_tty(key->infd, tmp);
- if (buf[strlen(buf) -1] == '\n') {
- buf[strlen(buf) - 1] = '\0';
- }
- return strlen(buf);
- }
- /*!
- * \brief return the ast_key structure for name
- * \see ast_key_get
- */
- struct ast_key * AST_OPTIONAL_API_NAME(ast_key_get)(const char *kname, int ktype)
- {
- struct ast_key *key;
- AST_RWLIST_RDLOCK(&keys);
- AST_RWLIST_TRAVERSE(&keys, key, list) {
- if (!strcmp(kname, key->name) &&
- (ktype == key->ktype)) {
- break;
- }
- }
- AST_RWLIST_UNLOCK(&keys);
- return key;
- }
- /*!
- * \brief load RSA key from file
- * \param dir directory string
- * \param fname name of file
- * \param ifd incoming file descriptor
- * \param ofd outgoing file descriptor
- * \param not2
- * \return key on success.
- * \retval NULL on failure.
- */
- static struct ast_key *try_load_key(const char *dir, const char *fname, int ifd, int ofd, int *not2)
- {
- int n, ktype = 0, found = 0;
- const char *c = NULL;
- char ffname[256];
- unsigned char digest[MD5_DIGEST_LENGTH];
- unsigned digestlen;
- FILE *f;
- EVP_MD_CTX *ctx = NULL;
- struct ast_key *key;
- static int notice = 0;
- struct stat st;
- size_t fnamelen = strlen(fname);
- /* Make sure its name is a public or private key */
- if (fnamelen > 4 && !strcmp((c = &fname[fnamelen - 4]), ".pub")) {
- ktype = AST_KEY_PUBLIC;
- } else if (fnamelen > 4 && !strcmp((c = &fname[fnamelen - 4]), ".key")) {
- ktype = AST_KEY_PRIVATE;
- } else {
- return NULL;
- }
- /* Get actual filename */
- n = snprintf(ffname, sizeof(ffname), "%s/%s", dir, fname);
- if (n >= sizeof(ffname)) {
- ast_log(LOG_WARNING,
- "Key filenames can be up to %zu bytes long, but the filename for the"
- " key we are currently trying to load (%s/%s) is %d bytes long.",
- sizeof(ffname) - 1, dir, fname, n);
- return NULL;
- }
- /* Open file */
- if (!(f = fopen(ffname, "r"))) {
- ast_log(LOG_WARNING, "Unable to open key file %s: %s\n", ffname, strerror(errno));
- return NULL;
- }
- n = fstat(fileno(f), &st);
- if (n != 0) {
- ast_log(LOG_ERROR, "Unable to stat key file: %s: %s\n", ffname, strerror(errno));
- fclose(f);
- return NULL;
- }
- if (!S_ISREG(st.st_mode)) {
- ast_log(LOG_ERROR, "Key file is not a regular file: %s\n", ffname);
- fclose(f);
- return NULL;
- }
- /* FILE_MODE_BITS is a bitwise OR of all possible file mode bits encoded in
- * the `st_mode` member of `struct stat`. For POSIX compatible systems this
- * will be 07777. */
- #define FILE_MODE_BITS (S_ISUID|S_ISGID|S_ISVTX|S_IRWXU|S_IRWXG|S_IRWXO)
- /* only user read or read/write modes allowed */
- if (ktype == AST_KEY_PRIVATE &&
- ((st.st_mode & FILE_MODE_BITS) & ~(S_IRUSR | S_IWUSR)) != 0) {
- ast_log(LOG_ERROR, "Private key file has bad permissions: %s: %#4o\n", ffname, st.st_mode & FILE_MODE_BITS);
- fclose(f);
- return NULL;
- }
- ctx = EVP_MD_CTX_create();
- if (ctx == NULL) {
- ast_log(LOG_ERROR, "Out of memory\n");
- fclose(f);
- return NULL;
- }
- EVP_DigestInit(ctx, EVP_md5());
- while (!feof(f)) {
- /* Calculate a "whatever" quality md5sum of the key */
- char buf[256] = "";
- if (!fgets(buf, sizeof(buf), f)) {
- continue;
- }
- if (!feof(f)) {
- EVP_DigestUpdate(ctx, (unsigned char *)buf, strlen(buf));
- }
- }
- EVP_DigestFinal(ctx, digest, &digestlen);
- EVP_MD_CTX_destroy(ctx);
- /* Look for an existing key */
- AST_RWLIST_TRAVERSE(&keys, key, list) {
- if (!strcasecmp(key->fn, ffname)) {
- break;
- }
- }
- if (key) {
- /* If the MD5 sum is the same, and it isn't awaiting a passcode
- then this is far enough */
- if (!memcmp(digest, key->digest, sizeof(digest)) &&
- !(key->ktype & KEY_NEEDS_PASSCODE)) {
- fclose(f);
- key->delme = 0;
- return NULL;
- } else {
- /* Preserve keytype */
- ktype = key->ktype;
- /* Recycle the same structure */
- found++;
- }
- }
- if (!key) {
- if (!(key = ast_calloc(1, sizeof(*key)))) {
- fclose(f);
- return NULL;
- }
- }
- /* First the filename */
- ast_copy_string(key->fn, ffname, sizeof(key->fn));
- /* Then the name minus the suffix */
- snprintf(key->name, sizeof(key->name), "%.*s", (int)(c - fname), fname);
- key->ktype = ktype;
- /* Yes, assume we're going to be deleted */
- key->delme = 1;
- /* Keep the key type */
- memcpy(key->digest, digest, sizeof(key->digest));
- /* Can I/O takes the FD we're given */
- key->infd = ifd;
- key->outfd = ofd;
- /* Reset the file back to the beginning */
- rewind(f);
- /* Now load the key with the right method */
- if (ktype == AST_KEY_PUBLIC) {
- PEM_read_PUBKEY(f, &key->pkey, pw_cb, key);
- } else {
- PEM_read_PrivateKey(f, &key->pkey, pw_cb, key);
- }
- fclose(f);
- if (key->pkey) {
- if (EVP_PKEY_size(key->pkey) == (AST_CRYPTO_RSA_KEY_BITS / 8)) {
- /* Key loaded okay */
- key->ktype &= ~KEY_NEEDS_PASSCODE;
- ast_verb(3, "Loaded %s key '%s'\n", key->ktype == AST_KEY_PUBLIC ? "PUBLIC" : "PRIVATE", key->name);
- ast_debug(1, "Key '%s' loaded OK\n", key->name);
- key->delme = 0;
- } else {
- ast_log(LOG_NOTICE, "Key '%s' is not expected size.\n", key->name);
- }
- } else if (key->infd != -2) {
- ast_log(LOG_WARNING, "Key load %s '%s' failed\n", key->ktype == AST_KEY_PUBLIC ? "PUBLIC" : "PRIVATE", key->name);
- if (ofd > -1) {
- ERR_print_errors_fp(stderr);
- } else {
- ERR_print_errors_fp(stderr);
- }
- } else {
- ast_log(LOG_NOTICE, "Key '%s' needs passcode.\n", key->name);
- key->ktype |= KEY_NEEDS_PASSCODE;
- if (!notice) {
- if (!ast_opt_init_keys) {
- ast_log(LOG_NOTICE, "Add the '-i' flag to the asterisk command line if you want to automatically initialize passcodes at launch.\n");
- }
- notice++;
- }
- /* Keep it anyway */
- key->delme = 0;
- /* Print final notice about "keys init" when done */
- *not2 = 1;
- }
- /* If this is a new key add it to the list */
- if (!found) {
- AST_RWLIST_INSERT_TAIL(&keys, key, list);
- }
- return key;
- }
- static int evp_pkey_sign(EVP_PKEY *pkey, const unsigned char *in, unsigned inlen, unsigned char *sig, unsigned *siglen, unsigned padding)
- {
- EVP_PKEY_CTX *ctx = NULL;
- int res = -1;
- size_t _siglen;
- if (*siglen < EVP_PKEY_size(pkey)) {
- return -1;
- }
- if ((ctx = EVP_PKEY_CTX_new(pkey, NULL)) == NULL) {
- return -1;
- }
- do {
- if ((res = EVP_PKEY_sign_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;
- }
- _siglen = *siglen;
- if ((res = EVP_PKEY_sign(ctx, sig, &_siglen, in, inlen)) <= 0) {
- break;
- }
- *siglen = _siglen;
- } while (0);
- EVP_PKEY_CTX_free(ctx);
- return res;
- }
- /*!
- * \brief signs outgoing message with public key
- * \see ast_sign_bin
- */
- int AST_OPTIONAL_API_NAME(ast_sign_bin)(struct ast_key *key, const char *msg, int msglen, unsigned char *dsig)
- {
- unsigned char digest[SHA_DIGEST_LENGTH];
- unsigned digestlen, siglen = 128;
- int res;
- EVP_MD_CTX *ctx = NULL;
- if (key->ktype != AST_KEY_PRIVATE) {
- ast_log(LOG_WARNING, "Cannot sign with a public key\n");
- return -1;
- }
- if (siglen < EVP_PKEY_size(key->pkey)) {
- ast_log(LOG_WARNING, "Signature buffer too small\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_sign(key->pkey, digest, sizeof(digest), dsig, &siglen, RSA_PKCS1_PADDING)) <= 0) {
- ast_log(LOG_WARNING, "RSA Signature (key %s) failed %d\n", key->name, res);
- return -1;
- }
- if (siglen != EVP_PKEY_size(key->pkey)) {
- ast_log(LOG_WARNING, "Unexpected signature length %u, expecting %d\n", siglen, EVP_PKEY_size(key->pkey));
- return -1;
- }
- return 0;
- }
- static int evp_pkey_decrypt(EVP_PKEY *pkey, const unsigned char *in, unsigned inlen, unsigned char *out, unsigned *outlen, unsigned padding)
- {
- EVP_PKEY_CTX *ctx = NULL;
- int res = -1;
- size_t _outlen;
- if (*outlen < EVP_PKEY_size(pkey)) {
- return -1;
- }
- if (inlen != EVP_PKEY_size(pkey)) {
- return -1;
- }
- if ((ctx = EVP_PKEY_CTX_new(pkey, NULL)) == NULL) {
- return -1;
- }
- do {
- if ((res = EVP_PKEY_decrypt_init(ctx)) <= 0) {
- break;
- }
- if ((res = EVP_PKEY_CTX_set_rsa_padding(ctx, padding)) <= 0) {
- break;
- }
- _outlen = *outlen;
- if ((res = EVP_PKEY_decrypt(ctx, out, &_outlen, in, inlen)) <= 0) {
- break;
- }
- res = *outlen = _outlen;
- } while (0);
- EVP_PKEY_CTX_free(ctx);
- return res;
- }
- /*!
- * \brief decrypt a message
- * \see ast_decrypt_bin
- */
- int AST_OPTIONAL_API_NAME(ast_decrypt_bin)(unsigned char *dst, const unsigned char *src, int srclen, struct ast_key *key)
- {
- int res;
- unsigned pos = 0, dstlen, blocksize;
- if (key->ktype != AST_KEY_PRIVATE) {
- ast_log(LOG_WARNING, "Cannot decrypt with a public key\n");
- return -1;
- }
- blocksize = EVP_PKEY_size(key->pkey);
- if (srclen % blocksize) {
- ast_log(LOG_NOTICE, "Tried to decrypt something not a multiple of %u bytes\n", blocksize);
- return -1;
- }
- 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) {
- return -1;
- }
- pos += dstlen;
- src += blocksize;
- srclen -= blocksize;
- dst += dstlen;
- }
- return pos;
- }
- static int evp_pkey_encrypt(EVP_PKEY *pkey, const unsigned char *in, unsigned inlen, unsigned char *out, unsigned *outlen, unsigned padding)
- {
- EVP_PKEY_CTX *ctx = NULL;
- int res = -1;
- size_t _outlen;
- if (padding != RSA_PKCS1_OAEP_PADDING) {
- ast_log(LOG_WARNING, "Only OAEP padding is supported for now\n");
- return -1;
- }
- if (inlen > EVP_PKEY_size(pkey) - RSA_PKCS1_OAEP_PADDING_SIZE) {
- return -1;
- }
- if (*outlen < EVP_PKEY_size(pkey)) {
- return -1;
- }
- do {
- if ((ctx = EVP_PKEY_CTX_new(pkey, NULL)) == NULL) {
- break;
- }
- if ((res = EVP_PKEY_encrypt_init(ctx)) <= 0) {
- break;
- }
- 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;
- }
- struct crypto_load_on_file {
- int ifd;
- int ofd;
- int note;
- };
- static int crypto_load_cb(const char *directory, const char *file, void *obj)
- {
- struct crypto_load_on_file *on_file = obj;
- try_load_key(directory, file, on_file->ifd, on_file->ofd, &on_file->note);
- return 0;
- }
- /*!
- * \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;
- struct crypto_load_on_file on_file = { ifd, ofd, 0 };
- AST_RWLIST_WRLOCK(&keys);
- /* Mark all keys for deletion */
- AST_RWLIST_TRAVERSE(&keys, key, list) {
- key->delme = 1;
- }
- if (ast_file_read_dirs(ast_config_AST_KEY_DIR, crypto_load_cb, &on_file, 1) == -1) {
- ast_log(LOG_WARNING, "Unable to open key directory '%s'\n", ast_config_AST_KEY_DIR);
- }
- if (on_file.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 */
- );
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