Update libsrtp to version 2.0

crypto/kernel/crypto_kernel.c

+/*
+ * crypto_kernel.c
+ *
+ * header for the cryptographic kernel
+ *
+ * David A. McGrew
+ * Cisco Systems, Inc.
+ */
+/*
+ *
+ * Copyright(c) 2001-2006,2013 Cisco Systems, Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *   Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *
+ *   Redistributions in binary form must reproduce the above
+ *   copyright notice, this list of conditions and the following
+ *   disclaimer in the documentation and/or other materials provided
+ *   with the distribution.
+ *
+ *   Neither the name of the Cisco Systems, Inc. nor the names of its
+ *   contributors may be used to endorse or promote products derived
+ *   from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+
+#ifdef HAVE_CONFIG_H
+    #include <config.h>
+#endif
+
+#include "alloc.h"
+
+#include "crypto_kernel.h"
+
+/* the debug module for the crypto_kernel */
+
+srtp_debug_module_t srtp_mod_crypto_kernel = {
+    0,                /* debugging is off by default */
+    "crypto kernel"   /* printable name for module   */
+};
+
+/*
+ * other generic debug modules that can be included in the kernel
+ */
+
+extern srtp_debug_module_t srtp_mod_auth;
+extern srtp_debug_module_t srtp_mod_cipher;
+extern srtp_debug_module_t mod_stat;
+extern srtp_debug_module_t mod_alloc;
+
+/*
+ * cipher types that can be included in the kernel
+ */
+
+extern srtp_cipher_type_t srtp_null_cipher;
+extern srtp_cipher_type_t srtp_aes_icm;
+#ifdef OPENSSL
+extern srtp_cipher_type_t srtp_aes_icm_192;
+extern srtp_cipher_type_t srtp_aes_icm_256;
+extern srtp_cipher_type_t srtp_aes_gcm_128_openssl;
+extern srtp_cipher_type_t srtp_aes_gcm_256_openssl;
+#endif
+
+/* debug modules for cipher types */
+extern srtp_debug_module_t srtp_mod_aes_icm;
+#ifdef OPENSSL
+extern srtp_debug_module_t srtp_mod_aes_gcm;
+#endif
+
+/*
+ * auth func types that can be included in the kernel
+ */
+
+extern srtp_auth_type_t srtp_null_auth;
+extern srtp_auth_type_t srtp_hmac;
+
+/* debug modules for auth types */
+extern srtp_debug_module_t srtp_mod_hmac;
+
+/* crypto_kernel is a global variable, the only one of its datatype */
+
+srtp_crypto_kernel_t crypto_kernel = {
+    srtp_crypto_kernel_state_insecure, /* start off in insecure state */
+    NULL,                              /* no cipher types yet         */
+    NULL,                              /* no auth types yet           */
+    NULL                               /* no debug modules yet        */
+};
+
+#define MAX_RNG_TRIALS 25
+
+srtp_err_status_t srtp_crypto_kernel_init ()
+{
+    srtp_err_status_t status;
+
+    /* check the security state */
+    if (crypto_kernel.state == srtp_crypto_kernel_state_secure) {
+
+        /*
+         * we're already in the secure state, but we've been asked to
+         * re-initialize, so we just re-run the self-tests and then return
+         */
+        return srtp_crypto_kernel_status();
+    }
+
+    /* initialize error reporting system */
+    status = srtp_err_reporting_init("crypto");
+    if (status) {
+        return status;
+    }
+
+    /* load debug modules */
+    status = srtp_crypto_kernel_load_debug_module(&srtp_mod_crypto_kernel);
+    if (status) {
+        return status;
+    }
+    status = srtp_crypto_kernel_load_debug_module(&srtp_mod_auth);
+    if (status) {
+        return status;
+    }
+    status = srtp_crypto_kernel_load_debug_module(&srtp_mod_cipher);
+    if (status) {
+        return status;
+    }
+    status = srtp_crypto_kernel_load_debug_module(&mod_stat);
+    if (status) {
+        return status;
+    }
+    status = srtp_crypto_kernel_load_debug_module(&mod_alloc);
+    if (status) {
+        return status;
+    }
+
+    /* load cipher types */
+    status = srtp_crypto_kernel_load_cipher_type(&srtp_null_cipher, SRTP_NULL_CIPHER);
+    if (status) {
+        return status;
+    }
+    status = srtp_crypto_kernel_load_cipher_type(&srtp_aes_icm, SRTP_AES_ICM);
+    if (status) {
+        return status;
+    }
+    status = srtp_crypto_kernel_load_debug_module(&srtp_mod_aes_icm);
+    if (status) {
+        return status;
+    }
+#ifdef OPENSSL
+    status = srtp_crypto_kernel_load_cipher_type(&srtp_aes_icm_192, SRTP_AES_192_ICM);
+    if (status) {
+        return status;
+    }
+    status = srtp_crypto_kernel_load_cipher_type(&srtp_aes_icm_256, SRTP_AES_256_ICM);
+    if (status) {
+        return status;
+    }
+    status = srtp_crypto_kernel_load_cipher_type(&srtp_aes_gcm_128_openssl, SRTP_AES_128_GCM);
+    if (status) {
+        return status;
+    }
+    status = srtp_crypto_kernel_load_cipher_type(&srtp_aes_gcm_256_openssl, SRTP_AES_256_GCM);
+    if (status) {
+        return status;
+    }
+    status = srtp_crypto_kernel_load_debug_module(&srtp_mod_aes_gcm);
+    if (status) {
+        return status;
+    }
+#endif
+
+    /* load auth func types */
+    status = srtp_crypto_kernel_load_auth_type(&srtp_null_auth, SRTP_NULL_AUTH);
+    if (status) {
+        return status;
+    }
+    status = srtp_crypto_kernel_load_auth_type(&srtp_hmac, SRTP_HMAC_SHA1);
+    if (status) {
+        return status;
+    }
+    status = srtp_crypto_kernel_load_debug_module(&srtp_mod_hmac);
+    if (status) {
+        return status;
+    }
+
+    /* change state to secure */
+    crypto_kernel.state = srtp_crypto_kernel_state_secure;
+
+    return srtp_err_status_ok;
+}
+
+srtp_err_status_t srtp_crypto_kernel_status ()
+{
+    srtp_err_status_t status;
+    srtp_kernel_cipher_type_t  *ctype = crypto_kernel.cipher_type_list;
+    srtp_kernel_auth_type_t    *atype = crypto_kernel.auth_type_list;
+    srtp_kernel_debug_module_t *dm    = crypto_kernel.debug_module_list;
+
+    /* for each cipher type, describe and test */
+    while (ctype != NULL) {
+        printf("cipher: %s\n", ctype->cipher_type->description);
+        printf("  self-test: ");
+        status = srtp_cipher_type_self_test(ctype->cipher_type);
+        if (status) {
+            printf("failed with error code %d\n", status);
+            exit(status);
+        }
+        printf("passed\n");
+        ctype = ctype->next;
+    }
+
+    /* for each auth type, describe and test */
+    while (atype != NULL) {
+        printf("auth func: %s\n", atype->auth_type->description);
+        printf("  self-test: ");
+        status = srtp_auth_type_self_test(atype->auth_type);
+        if (status) {
+            printf("failed with error code %d\n", status);
+            exit(status);
+        }
+        printf("passed\n");
+        atype = atype->next;
+    }
+
+    /* describe each debug module */
+    printf("debug modules loaded:\n");
+    while (dm != NULL) {
+        printf("  %s ", dm->mod->name);
+        if (dm->mod->on) {
+            printf("(on)\n");
+        } else{
+            printf("(off)\n");
+        }
+        dm = dm->next;
+    }
+
+    return srtp_err_status_ok;
+}
+
+srtp_err_status_t srtp_crypto_kernel_list_debug_modules ()
+{
+    srtp_kernel_debug_module_t *dm = crypto_kernel.debug_module_list;
+
+    /* describe each debug module */
+    printf("debug modules loaded:\n");
+    while (dm != NULL) {
+        printf("  %s ", dm->mod->name);
+        if (dm->mod->on) {
+            printf("(on)\n");
+        } else{
+            printf("(off)\n");
+        }
+        dm = dm->next;
+    }
+
+    return srtp_err_status_ok;
+}
+
+srtp_err_status_t srtp_crypto_kernel_shutdown ()
+{
+    /*
+     * free dynamic memory used in crypto_kernel at present
+     */
+
+    /* walk down cipher type list, freeing memory */
+    while (crypto_kernel.cipher_type_list != NULL) {
+        srtp_kernel_cipher_type_t *ctype = crypto_kernel.cipher_type_list;
+        crypto_kernel.cipher_type_list = ctype->next;
+        debug_print(srtp_mod_crypto_kernel,
+                    "freeing memory for cipher %s",
+                    ctype->cipher_type->description);
+        srtp_crypto_free(ctype);
+    }
+
+    /* walk down authetication module list, freeing memory */
+    while (crypto_kernel.auth_type_list != NULL) {
+        srtp_kernel_auth_type_t *atype = crypto_kernel.auth_type_list;
+        crypto_kernel.auth_type_list = atype->next;
+        debug_print(srtp_mod_crypto_kernel,
+                    "freeing memory for authentication %s",
+                    atype->auth_type->description);
+        srtp_crypto_free(atype);
+    }
+
+    /* walk down debug module list, freeing memory */
+    while (crypto_kernel.debug_module_list != NULL) {
+        srtp_kernel_debug_module_t *kdm = crypto_kernel.debug_module_list;
+        crypto_kernel.debug_module_list = kdm->next;
+        debug_print(srtp_mod_crypto_kernel,
+                    "freeing memory for debug module %s",
+                    kdm->mod->name);
+        srtp_crypto_free(kdm);
+    }
+
+    /* return to insecure state */
+    crypto_kernel.state = srtp_crypto_kernel_state_insecure;
+
+    return srtp_err_status_ok;
+}
+
+static inline srtp_err_status_t srtp_crypto_kernel_do_load_cipher_type (const srtp_cipher_type_t *new_ct, srtp_cipher_type_id_t id, int replace)
+{
+    srtp_kernel_cipher_type_t *ctype, *new_ctype;
+    srtp_err_status_t status;
+
+    /* defensive coding */
+    if (new_ct == NULL) {
+        return srtp_err_status_bad_param;
+    }
+
+    if (new_ct->id != id) {
+        return srtp_err_status_bad_param;
+    }
+
+    /* check cipher type by running self-test */
+    status = srtp_cipher_type_self_test(new_ct);
+    if (status) {
+        return status;
+    }
+
+    /* walk down list, checking if this type is in the list already  */
+    ctype = crypto_kernel.cipher_type_list;
+    while (ctype != NULL) {
+        if (id == ctype->id) {
+            if (!replace) {
+                return srtp_err_status_bad_param;
+            }
+            status = srtp_cipher_type_test(new_ct, ctype->cipher_type->test_data);
+            if (status) {
+                return status;
+            }
+            new_ctype = ctype;
+            break;
+        }else if (new_ct == ctype->cipher_type) {
+            return srtp_err_status_bad_param;
+        }
+        ctype = ctype->next;
+    }
+
+    /* if not found, put new_ct at the head of the list */
+    if (ctype == NULL) {
+        /* allocate memory */
+        new_ctype = (srtp_kernel_cipher_type_t*)srtp_crypto_alloc(sizeof(srtp_kernel_cipher_type_t));
+        if (new_ctype == NULL) {
+            return srtp_err_status_alloc_fail;
+        }
+        new_ctype->next = crypto_kernel.cipher_type_list;
+
+        /* set head of list to new cipher type */
+        crypto_kernel.cipher_type_list = new_ctype;
+    }
+
+    /* set fields */
+    new_ctype->cipher_type = new_ct;
+    new_ctype->id = id;
+
+    return srtp_err_status_ok;
+}
+
+srtp_err_status_t srtp_crypto_kernel_load_cipher_type (const srtp_cipher_type_t *new_ct, srtp_cipher_type_id_t id)
+{
+    return srtp_crypto_kernel_do_load_cipher_type(new_ct, id, 0);
+}
+
+srtp_err_status_t srtp_replace_cipher_type (const srtp_cipher_type_t *new_ct, srtp_cipher_type_id_t id)
+{
+    return srtp_crypto_kernel_do_load_cipher_type(new_ct, id, 1);
+}
+
+srtp_err_status_t srtp_crypto_kernel_do_load_auth_type (const srtp_auth_type_t *new_at, srtp_auth_type_id_t id, int replace)
+{
+    srtp_kernel_auth_type_t *atype, *new_atype;
+    srtp_err_status_t status;
+
+    /* defensive coding */
+    if (new_at == NULL) {
+        return srtp_err_status_bad_param;
+    }
+
+    if (new_at->id != id) {
+        return srtp_err_status_bad_param;
+    }
+
+    /* check auth type by running self-test */
+    status = srtp_auth_type_self_test(new_at);
+    if (status) {
+        return status;
+    }
+
+    /* walk down list, checking if this type is in the list already  */
+    atype = crypto_kernel.auth_type_list;
+    while (atype != NULL) {
+        if (id == atype->id) {
+            if (!replace) {
+                return srtp_err_status_bad_param;
+            }
+            status = srtp_auth_type_test(new_at, atype->auth_type->test_data);
+            if (status) {
+                return status;
+            }
+            new_atype = atype;
+            break;
+        }else if (new_at == atype->auth_type) {
+            return srtp_err_status_bad_param;
+        }
+        atype = atype->next;
+    }
+
+    /* if not found, put new_at at the head of the list */
+    if (atype == NULL) {
+        /* allocate memory */
+        new_atype = (srtp_kernel_auth_type_t*)srtp_crypto_alloc(sizeof(srtp_kernel_auth_type_t));
+        if (new_atype == NULL) {
+            return srtp_err_status_alloc_fail;
+        }
+
+        new_atype->next = crypto_kernel.auth_type_list;
+        /* set head of list to new auth type */
+        crypto_kernel.auth_type_list = new_atype;
+    }
+
+    /* set fields */
+    new_atype->auth_type = new_at;
+    new_atype->id = id;
+
+    return srtp_err_status_ok;
+
+}
+
+srtp_err_status_t srtp_crypto_kernel_load_auth_type (const srtp_auth_type_t *new_at, srtp_auth_type_id_t id)
+{
+    return srtp_crypto_kernel_do_load_auth_type(new_at, id, 0);
+}
+
+srtp_err_status_t srtp_replace_auth_type (const srtp_auth_type_t *new_at, srtp_auth_type_id_t id)
+{
+    return srtp_crypto_kernel_do_load_auth_type(new_at, id, 1);
+}
+
+
+const srtp_cipher_type_t * srtp_crypto_kernel_get_cipher_type (srtp_cipher_type_id_t id)
+{
+    srtp_kernel_cipher_type_t *ctype;
+
+    /* walk down list, looking for id  */
+    ctype = crypto_kernel.cipher_type_list;
+    while (ctype != NULL) {
+        if (id == ctype->id) {
+            return ctype->cipher_type;
+        }
+        ctype = ctype->next;
+    }
+
+    /* haven't found the right one, indicate failure by returning NULL */
+    return NULL;
+}
+
+
+srtp_err_status_t srtp_crypto_kernel_alloc_cipher (srtp_cipher_type_id_t id, srtp_cipher_pointer_t *cp, int key_len, int tag_len)
+{
+    const srtp_cipher_type_t *ct;
+
+    /*
+     * if the crypto_kernel is not yet initialized, we refuse to allocate
+     * any ciphers - this is a bit extra-paranoid
+     */
+    if (crypto_kernel.state != srtp_crypto_kernel_state_secure) {
+        return srtp_err_status_init_fail;
+    }
+
+    ct = srtp_crypto_kernel_get_cipher_type(id);
+    if (!ct) {
+        return srtp_err_status_fail;
+    }
+
+    return ((ct)->alloc(cp, key_len, tag_len));
+}
+
+
+
+const srtp_auth_type_t * srtp_crypto_kernel_get_auth_type (srtp_auth_type_id_t id)
+{
+    srtp_kernel_auth_type_t *atype;
+
+    /* walk down list, looking for id  */
+    atype = crypto_kernel.auth_type_list;
+    while (atype != NULL) {
+        if (id == atype->id) {
+            return atype->auth_type;
+        }
+        atype = atype->next;
+    }
+
+    /* haven't found the right one, indicate failure by returning NULL */
+    return NULL;
+}
+
+srtp_err_status_t srtp_crypto_kernel_alloc_auth (srtp_auth_type_id_t id, srtp_auth_pointer_t *ap, int key_len, int tag_len)
+{
+    const srtp_auth_type_t *at;
+
+    /*
+     * if the crypto_kernel is not yet initialized, we refuse to allocate
+     * any auth functions - this is a bit extra-paranoid
+     */
+    if (crypto_kernel.state != srtp_crypto_kernel_state_secure) {
+        return srtp_err_status_init_fail;
+    }
+
+    at = srtp_crypto_kernel_get_auth_type(id);
+    if (!at) {
+        return srtp_err_status_fail;
+    }
+
+    return ((at)->alloc(ap, key_len, tag_len));
+}
+
+srtp_err_status_t srtp_crypto_kernel_load_debug_module (srtp_debug_module_t *new_dm)
+{
+    srtp_kernel_debug_module_t *kdm, *new;
+
+    /* defensive coding */
+    if (new_dm == NULL) {
+        return srtp_err_status_bad_param;
+    }
+
+    /* walk down list, checking if this type is in the list already  */
+    kdm = crypto_kernel.debug_module_list;
+    while (kdm != NULL) {
+        if (strncmp(new_dm->name, kdm->mod->name, 64) == 0) {
+            return srtp_err_status_bad_param;
+        }
+        kdm = kdm->next;
+    }
+
+    /* put new_dm at the head of the list */
+    /* allocate memory */
+    new = (srtp_kernel_debug_module_t*)srtp_crypto_alloc(sizeof(srtp_kernel_debug_module_t));
+    if (new == NULL) {
+        return srtp_err_status_alloc_fail;
+    }
+
+    /* set fields */
+    new->mod = new_dm;
+    new->next = crypto_kernel.debug_module_list;
+
+    /* set head of list to new cipher type */
+    crypto_kernel.debug_module_list = new;
+
+    return srtp_err_status_ok;
+}
+
+srtp_err_status_t srtp_crypto_kernel_set_debug_module (char *name, int on)
+{
+    srtp_kernel_debug_module_t *kdm;
+
+    /* walk down list, checking if this type is in the list already  */
+    kdm = crypto_kernel.debug_module_list;
+    while (kdm != NULL) {
+        if (strncmp(name, kdm->mod->name, 64) == 0) {
+            kdm->mod->on = on;
+            return srtp_err_status_ok;
+        }
+        kdm = kdm->next;
+    }
+
+    return srtp_err_status_fail;
+}