Rework LuCI build system

 * Rename subdirectories to their repective OpenWrt package names
 * Make each LuCI module its own standalone package
 * Deploy a shared luci.mk which is used by each module Makefile

Signed-off-by: Jo-Philipp Wich <jow@openwrt.org>

1 files changed, 2057 insertions, 0 deletions

diff --git a/libs/luci-lib-nixio/axTLS/ssl/tls1.c b/libs/luci-lib-nixio/axTLS/ssl/tls1.c
new file mode 100755
index 0000000000..658c2c15d4
--- /dev/null
+++ b/libs/luci-lib-nixio/axTLS/ssl/tls1.c
@@ -0,0 +1,2057 @@
+/*
+ * Copyright (c) 2007, Cameron Rich
+ * 
+ * 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 axTLS project 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 OWNER 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.
+ */
+
+/**
+ * Common ssl/tlsv1 code to both the client and server implementations.
+ */
+
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdarg.h>
+#include "ssl.h"
+
+/* The session expiry time */
+#define SSL_EXPIRY_TIME     (CONFIG_SSL_EXPIRY_TIME*3600)
+
+static const uint8_t g_hello_request[] = { HS_HELLO_REQUEST, 0, 0, 0 };
+static const uint8_t g_chg_cipher_spec_pkt[] = { 1 };
+static const char * server_finished = "server finished";
+static const char * client_finished = "client finished";
+
+static int do_handshake(SSL *ssl, uint8_t *buf, int read_len);
+static void set_key_block(SSL *ssl, int is_write);
+static int verify_digest(SSL *ssl, int mode, const uint8_t *buf, int read_len);
+static void *crypt_new(SSL *ssl, uint8_t *key, uint8_t *iv, int is_decrypt);
+static int send_raw_packet(SSL *ssl, uint8_t protocol);
+
+/**
+ * The server will pick the cipher based on the order that the order that the
+ * ciphers are listed. This order is defined at compile time.
+ */
+#ifdef CONFIG_SSL_SKELETON_MODE
+const uint8_t ssl_prot_prefs[NUM_PROTOCOLS] = 
+{ SSL_RC4_128_SHA };
+#else
+static void session_free(SSL_SESSION *ssl_sessions[], int sess_index);
+
+const uint8_t ssl_prot_prefs[NUM_PROTOCOLS] = 
+#ifdef CONFIG_SSL_PROT_LOW                  /* low security, fast speed */
+{ SSL_RC4_128_SHA, SSL_AES128_SHA, SSL_AES256_SHA, SSL_RC4_128_MD5 };
+#elif CONFIG_SSL_PROT_MEDIUM                /* medium security, medium speed */
+{ SSL_AES128_SHA, SSL_AES256_SHA, SSL_RC4_128_SHA, SSL_RC4_128_MD5 };    
+#else /* CONFIG_SSL_PROT_HIGH */            /* high security, low speed */
+{ SSL_AES256_SHA, SSL_AES128_SHA, SSL_RC4_128_SHA, SSL_RC4_128_MD5 };
+#endif
+#endif /* CONFIG_SSL_SKELETON_MODE */
+
+/**
+ * The cipher map containing all the essentials for each cipher.
+ */
+#ifdef CONFIG_SSL_SKELETON_MODE
+static const cipher_info_t cipher_info[NUM_PROTOCOLS] = 
+{
+    {   /* RC4-SHA */
+        SSL_RC4_128_SHA,                /* RC4-SHA */
+        16,                             /* key size */
+        0,                              /* iv size */ 
+        2*(SHA1_SIZE+16),               /* key block size */
+        0,                              /* no padding */
+        SHA1_SIZE,                      /* digest size */
+        hmac_sha1,                      /* hmac algorithm */
+        (crypt_func)RC4_crypt,          /* encrypt */
+        (crypt_func)RC4_crypt           /* decrypt */
+    },
+};
+#else
+static const cipher_info_t cipher_info[NUM_PROTOCOLS] = 
+{
+    {   /* AES128-SHA */
+        SSL_AES128_SHA,                 /* AES128-SHA */
+        16,                             /* key size */
+        16,                             /* iv size */ 
+        2*(SHA1_SIZE+16+16),            /* key block size */
+        16,                             /* block padding size */
+        SHA1_SIZE,                      /* digest size */
+        hmac_sha1,                      /* hmac algorithm */
+        (crypt_func)AES_cbc_encrypt,    /* encrypt */
+        (crypt_func)AES_cbc_decrypt     /* decrypt */
+    },
+    {   /* AES256-SHA */
+        SSL_AES256_SHA,                 /* AES256-SHA */
+        32,                             /* key size */
+        16,                             /* iv size */ 
+        2*(SHA1_SIZE+32+16),            /* key block size */
+        16,                             /* block padding size */
+        SHA1_SIZE,                      /* digest size */
+        hmac_sha1,                      /* hmac algorithm */
+        (crypt_func)AES_cbc_encrypt,    /* encrypt */
+        (crypt_func)AES_cbc_decrypt     /* decrypt */
+    },       
+    {   /* RC4-SHA */
+        SSL_RC4_128_SHA,                /* RC4-SHA */
+        16,                             /* key size */
+        0,                              /* iv size */ 
+        2*(SHA1_SIZE+16),               /* key block size */
+        0,                              /* no padding */
+        SHA1_SIZE,                      /* digest size */
+        hmac_sha1,                      /* hmac algorithm */
+        (crypt_func)RC4_crypt,          /* encrypt */
+        (crypt_func)RC4_crypt           /* decrypt */
+    },
+    /*
+     * This protocol is from SSLv2 days and is unlikely to be used - but was
+     * useful for testing different possible digest algorithms.
+     */
+    {   /* RC4-MD5 */
+        SSL_RC4_128_MD5,                /* RC4-MD5 */
+        16,                             /* key size */
+        0,                              /* iv size */ 
+        2*(MD5_SIZE+16),                /* key block size */
+        0,                              /* no padding */
+        MD5_SIZE,                       /* digest size */
+        hmac_md5,                       /* hmac algorithm */
+        (crypt_func)RC4_crypt,          /* encrypt */
+        (crypt_func)RC4_crypt           /* decrypt */
+    },
+};
+#endif
+
+static void prf(const uint8_t *sec, int sec_len, uint8_t *seed, int seed_len,
+        uint8_t *out, int olen);
+static const cipher_info_t *get_cipher_info(uint8_t cipher);
+static void increment_read_sequence(SSL *ssl);
+static void increment_write_sequence(SSL *ssl);
+static void add_hmac_digest(SSL *ssl, int snd, uint8_t *hmac_header,
+        const uint8_t *buf, int buf_len, uint8_t *hmac_buf);
+
+/* win32 VC6.0 doesn't have variadic macros */
+#if defined(WIN32) && !defined(CONFIG_SSL_FULL_MODE)
+void DISPLAY_BYTES(SSL *ssl, const char *format, 
+        const uint8_t *data, int size, ...) {}
+#endif
+
+/**
+ * Establish a new client/server context.
+ */
+EXP_FUNC SSL_CTX *STDCALL ssl_ctx_new(uint32_t options, int num_sessions)
+{
+    SSL_CTX *ssl_ctx = (SSL_CTX *)calloc(1, sizeof (SSL_CTX));
+    ssl_ctx->options = options;
+
+    if (load_key_certs(ssl_ctx) < 0)
+    {
+        free(ssl_ctx);  /* can't load our key/certificate pair, so die */
+        return NULL;
+    }
+
+#ifndef CONFIG_SSL_SKELETON_MODE
+    ssl_ctx->num_sessions = num_sessions;
+#endif
+
+    SSL_CTX_MUTEX_INIT(ssl_ctx->mutex);
+
+#ifndef CONFIG_SSL_SKELETON_MODE
+    if (num_sessions)
+    {
+        ssl_ctx->ssl_sessions = (SSL_SESSION **)
+                        calloc(1, num_sessions*sizeof(SSL_SESSION *));
+    }
+#endif
+
+    return ssl_ctx;
+}
+
+/*
+ * Remove a client/server context.
+ */
+EXP_FUNC void STDCALL ssl_ctx_free(SSL_CTX *ssl_ctx)
+{
+    SSL *ssl;
+    int i;
+
+    if (ssl_ctx == NULL)
+        return;
+
+    ssl = ssl_ctx->head;
+
+    /* clear out all the ssl entries */
+    while (ssl)
+    {
+        SSL *next = ssl->next;
+        ssl_free(ssl);
+        ssl = next;
+    }
+
+#ifndef CONFIG_SSL_SKELETON_MODE
+    /* clear out all the sessions */
+    for (i = 0; i < ssl_ctx->num_sessions; i++)
+        session_free(ssl_ctx->ssl_sessions, i);
+
+    free(ssl_ctx->ssl_sessions);
+#endif
+
+    i = 0;
+    while (i < CONFIG_SSL_MAX_CERTS && ssl_ctx->certs[i].buf)
+    {
+        free(ssl_ctx->certs[i].buf);
+        ssl_ctx->certs[i++].buf = NULL;
+    }
+
+#ifdef CONFIG_SSL_CERT_VERIFICATION
+    remove_ca_certs(ssl_ctx->ca_cert_ctx);
+#endif
+    ssl_ctx->chain_length = 0;
+    SSL_CTX_MUTEX_DESTROY(ssl_ctx->mutex);
+    RSA_free(ssl_ctx->rsa_ctx);
+    RNG_terminate();
+    free(ssl_ctx);
+}
+
+/*
+ * Free any used resources used by this connection.
+ */
+EXP_FUNC void STDCALL ssl_free(SSL *ssl)
+{
+    SSL_CTX *ssl_ctx;
+
+    if (ssl == NULL)        /* just ignore null pointers */
+        return;
+
+    /* spec says we must notify when we are dying */
+    send_alert(ssl, SSL_ALERT_CLOSE_NOTIFY);
+
+    ssl_ctx = ssl->ssl_ctx;
+
+    SSL_CTX_LOCK(ssl_ctx->mutex);
+
+    /* adjust the server SSL list */
+    if (ssl->prev)
+        ssl->prev->next = ssl->next;
+    else
+        ssl_ctx->head = ssl->next;
+
+    if (ssl->next)
+        ssl->next->prev = ssl->prev;
+    else
+        ssl_ctx->tail = ssl->prev;
+
+    SSL_CTX_UNLOCK(ssl_ctx->mutex);
+
+    /* may already be free - but be sure */
+    free(ssl->encrypt_ctx);
+    free(ssl->decrypt_ctx);
+    disposable_free(ssl);
+#ifdef CONFIG_SSL_CERT_VERIFICATION
+    x509_free(ssl->x509_ctx);
+#endif
+
+    free(ssl);
+}
+
+/*
+ * Read the SSL connection and send any alerts for various errors.
+ */
+EXP_FUNC int STDCALL ssl_read(SSL *ssl, uint8_t **in_data)
+{
+    int ret = basic_read(ssl, in_data);
+
+    /* check for return code so we can send an alert */
+    if (ret < SSL_OK)
+    {
+        if (ret != SSL_ERROR_CONN_LOST)
+        {
+            send_alert(ssl, ret);
+#ifndef CONFIG_SSL_SKELETON_MODE
+            /* something nasty happened, so get rid of this session */
+            kill_ssl_session(ssl->ssl_ctx->ssl_sessions, ssl);
+#endif
+        }
+    }
+
+    return ret;
+}
+
+/*
+ * Write application data to the client
+ */
+EXP_FUNC int STDCALL ssl_write(SSL *ssl, const uint8_t *out_data, int out_len)
+{
+    int n = out_len, nw, i, tot = 0;
+
+    /* maximum size of a TLS packet is around 16kB, so fragment */
+    do 
+    {
+        nw = n;
+
+        if (nw > RT_MAX_PLAIN_LENGTH)    /* fragment if necessary */
+            nw = RT_MAX_PLAIN_LENGTH;
+
+        if ((i = send_packet(ssl, PT_APP_PROTOCOL_DATA, 
+                                            &out_data[tot], nw)) <= 0)
+        {
+            out_len = i;    /* an error */
+            break;
+        }
+
+        tot += i;
+        n -= i;
+    } while (n > 0);
+
+    return out_len;
+}
+
+/**
+ * Add a certificate to the certificate chain.
+ */
+int add_cert(SSL_CTX *ssl_ctx, const uint8_t *buf, int len)
+{
+    int ret = SSL_ERROR_NO_CERT_DEFINED, i = 0;
+    SSL_CERT *ssl_cert;
+    X509_CTX *cert = NULL;
+    int offset;
+
+    while (ssl_ctx->certs[i].buf && i < CONFIG_SSL_MAX_CERTS) 
+        i++;
+
+    if (i == CONFIG_SSL_MAX_CERTS) /* too many certs */
+    {
+#ifdef CONFIG_SSL_FULL_MODE
+        printf("Error: maximum number of certs added - change of "
+                "compile-time configuration required\n");
+#endif
+        goto error;
+    }
+
+    if ((ret = x509_new(buf, &offset, &cert)))
+        goto error;
+
+#if defined (CONFIG_SSL_FULL_MODE)
+    if (ssl_ctx->options & SSL_DISPLAY_CERTS)
+        x509_print(cert, NULL);
+#endif
+
+    ssl_cert = &ssl_ctx->certs[i];
+    ssl_cert->size = len;
+    ssl_cert->buf = (uint8_t *)malloc(len);
+    memcpy(ssl_cert->buf, buf, len);
+    ssl_ctx->chain_length++;
+    len -= offset;
+    ret = SSL_OK;           /* ok so far */
+
+    /* recurse? */
+    if (len > 0)
+    {
+        ret = add_cert(ssl_ctx, &buf[offset], len);
+    }
+
+error:
+    x509_free(cert);        /* don't need anymore */
+    return ret;
+}
+
+#ifdef CONFIG_SSL_CERT_VERIFICATION
+/**
+ * Add a certificate authority.
+ */
+int add_cert_auth(SSL_CTX *ssl_ctx, const uint8_t *buf, int len)
+{
+    int ret = SSL_ERROR_NO_CERT_DEFINED;
+    int i = 0;
+    int offset;
+    CA_CERT_CTX *ca_cert_ctx;
+
+    if (ssl_ctx->ca_cert_ctx == NULL)
+        ssl_ctx->ca_cert_ctx = (CA_CERT_CTX *)calloc(1, sizeof(CA_CERT_CTX));
+
+    ca_cert_ctx = ssl_ctx->ca_cert_ctx;
+
+    while (i < CONFIG_X509_MAX_CA_CERTS && ca_cert_ctx->cert[i]) 
+        i++;
+
+    if (i > CONFIG_X509_MAX_CA_CERTS)
+    {
+#ifdef CONFIG_SSL_FULL_MODE
+        printf("Error: maximum number of CA certs added - change of "
+                "compile-time configuration required\n");
+#endif
+        goto error;
+    }
+
+    if ((ret = x509_new(buf, &offset, &ca_cert_ctx->cert[i])))
+        goto error;
+
+    len -= offset;
+    ret = SSL_OK;           /* ok so far */
+
+    /* recurse? */
+    if (len > 0)
+        ret = add_cert_auth(ssl_ctx, &buf[offset], len);
+
+error:
+    return ret;
+}
+
+/*
+ * Retrieve an X.509 distinguished name component
+ */
+EXP_FUNC const char * STDCALL ssl_get_cert_dn(const SSL *ssl, int component)
+{
+    if (ssl->x509_ctx == NULL)
+        return NULL;
+
+    switch (component)
+    {
+        case SSL_X509_CERT_COMMON_NAME:
+            return ssl->x509_ctx->cert_dn[X509_COMMON_NAME];
+
+        case SSL_X509_CERT_ORGANIZATION:
+            return ssl->x509_ctx->cert_dn[X509_ORGANIZATION];
+
+        case SSL_X509_CERT_ORGANIZATIONAL_NAME:       
+            return ssl->x509_ctx->cert_dn[X509_ORGANIZATIONAL_UNIT];
+
+        case SSL_X509_CA_CERT_COMMON_NAME:
+            return ssl->x509_ctx->ca_cert_dn[X509_COMMON_NAME];
+
+        case SSL_X509_CA_CERT_ORGANIZATION:
+            return ssl->x509_ctx->ca_cert_dn[X509_ORGANIZATION];
+
+        case SSL_X509_CA_CERT_ORGANIZATIONAL_NAME:       
+            return ssl->x509_ctx->ca_cert_dn[X509_ORGANIZATIONAL_UNIT];
+
+        default:
+            return NULL;
+    }
+}
+
+#endif
+
+/*
+ * Find an ssl object based on the client's file descriptor.
+ */
+EXP_FUNC SSL * STDCALL ssl_find(SSL_CTX *ssl_ctx, int client_fd)
+{
+    SSL *ssl;
+
+    SSL_CTX_LOCK(ssl_ctx->mutex);
+    ssl = ssl_ctx->head;
+
+    /* search through all the ssl entries */
+    while (ssl)
+    {
+        if (ssl->client_fd == client_fd)
+        {
+            SSL_CTX_UNLOCK(ssl_ctx->mutex);
+            return ssl;
+        }
+
+        ssl = ssl->next;
+    }
+
+    SSL_CTX_UNLOCK(ssl_ctx->mutex);
+    return NULL;
+}
+
+/*
+ * Force the client to perform its handshake again.
+ */
+EXP_FUNC int STDCALL ssl_renegotiate(SSL *ssl)
+{
+    int ret = SSL_OK;
+
+    disposable_new(ssl);
+#ifdef CONFIG_SSL_ENABLE_CLIENT
+    if (IS_SET_SSL_FLAG(SSL_IS_CLIENT))
+    {
+        ret = do_client_connect(ssl);
+    }
+    else
+#endif
+    {
+        send_packet(ssl, PT_HANDSHAKE_PROTOCOL, 
+                g_hello_request, sizeof(g_hello_request));
+        SET_SSL_FLAG(SSL_NEED_RECORD);
+    }
+
+    return ret;
+}
+
+/**
+ * @brief Get what we need for key info.
+ * @param cipher    [in]    The cipher information we are after
+ * @param key_size  [out]   The key size for the cipher
+ * @param iv_size   [out]   The iv size for the cipher
+ * @return  The amount of key information we need.
+ */
+static const cipher_info_t *get_cipher_info(uint8_t cipher)
+{
+    int i;
+
+    for (i = 0; i < NUM_PROTOCOLS; i++)
+    {
+        if (cipher_info[i].cipher == cipher)
+        {
+            return &cipher_info[i];
+        }
+    }
+
+    return NULL;  /* error */
+}
+
+/*
+ * Get a new ssl context for a new connection.
+ */
+SSL *ssl_new(SSL_CTX *ssl_ctx, int client_fd)
+{
+    SSL *ssl = (SSL *)calloc(1, sizeof(SSL));
+    ssl->ssl_ctx = ssl_ctx;
+    ssl->need_bytes = SSL_RECORD_SIZE;      /* need a record */
+    ssl->client_fd = client_fd;
+    ssl->flag = SSL_NEED_RECORD;
+    ssl->bm_data = ssl->bm_all_data+BM_RECORD_OFFSET; /* space at the start */
+    ssl->hs_status = SSL_NOT_OK;            /* not connected */
+#ifdef CONFIG_ENABLE_VERIFICATION
+    ssl->ca_cert_ctx = ssl_ctx->ca_cert_ctx;
+#endif
+    disposable_new(ssl);
+
+    /* a bit hacky but saves a few bytes of memory */
+    ssl->flag |= ssl_ctx->options;
+    SSL_CTX_LOCK(ssl_ctx->mutex);
+
+    if (ssl_ctx->head == NULL)
+    {
+        ssl_ctx->head = ssl;
+        ssl_ctx->tail = ssl;
+    }
+    else
+    {
+        ssl->prev = ssl_ctx->tail;
+        ssl_ctx->tail->next = ssl;
+        ssl_ctx->tail = ssl;
+    }
+
+    SSL_CTX_UNLOCK(ssl_ctx->mutex);
+    return ssl;
+}
+
+/*
+ * Add a private key to a context.
+ */
+int add_private_key(SSL_CTX *ssl_ctx, SSLObjLoader *ssl_obj)
+{
+    int ret = SSL_OK;
+
+    /* get the private key details */
+    if (asn1_get_private_key(ssl_obj->buf, ssl_obj->len, &ssl_ctx->rsa_ctx))
+    {
+        ret = SSL_ERROR_INVALID_KEY;
+        goto error;
+    }
+
+error:
+    return ret;
+}
+
+/** 
+ * Increment the read sequence number (as a 64 bit endian indepenent #)
+ */     
+static void increment_read_sequence(SSL *ssl)
+{
+    int i;
+
+    for (i = 7; i >= 0; i--) 
+    {       
+        if (++ssl->read_sequence[i])
+            break;
+    }
+}
+            
+/**
+ * Increment the read sequence number (as a 64 bit endian indepenent #)
+ */      
+static void increment_write_sequence(SSL *ssl)
+{        
+    int i;                  
+         
+    for (i = 7; i >= 0; i--)
+    {                       
+        if (++ssl->write_sequence[i])
+            break;
+    }                       
+}
+
+/**
+ * Work out the HMAC digest in a packet.
+ */
+static void add_hmac_digest(SSL *ssl, int mode, uint8_t *hmac_header,
+        const uint8_t *buf, int buf_len, uint8_t *hmac_buf)
+{
+    int hmac_len = buf_len + 8 + SSL_RECORD_SIZE;
+    uint8_t *t_buf = (uint8_t *)alloca(hmac_len+10);
+
+    memcpy(t_buf, (mode == SSL_SERVER_WRITE || mode == SSL_CLIENT_WRITE) ? 
+                    ssl->write_sequence : ssl->read_sequence, 8);
+    memcpy(&t_buf[8], hmac_header, SSL_RECORD_SIZE);
+    memcpy(&t_buf[8+SSL_RECORD_SIZE], buf, buf_len);
+
+    ssl->cipher_info->hmac(t_buf, hmac_len, 
+            (mode == SSL_SERVER_WRITE || mode == SSL_CLIENT_READ) ? 
+                ssl->server_mac : ssl->client_mac, 
+            ssl->cipher_info->digest_size, hmac_buf);
+
+#if 0
+    print_blob("record", ssl->hmac_tx, SSL_RECORD_SIZE);
+    print_blob("buf", buf, buf_len);
+    if (mode == SSL_SERVER_WRITE || mode == SSL_CLIENT_WRITE)
+    {
+        print_blob("write seq", ssl->write_sequence, 8);
+    }
+    else
+    {
+        print_blob("read seq", ssl->read_sequence, 8);
+    }
+
+    if (mode == SSL_SERVER_WRITE || mode == SSL_CLIENT_READ)
+    {
+        print_blob("server mac", 
+                ssl->server_mac, ssl->cipher_info->digest_size);
+    }
+    else
+    {
+        print_blob("client mac", 
+                ssl->client_mac, ssl->cipher_info->digest_size);
+    }
+    print_blob("hmac", hmac_buf, SHA1_SIZE);
+#endif
+}
+
+/**
+ * Verify that the digest of a packet is correct.
+ */
+static int verify_digest(SSL *ssl, int mode, const uint8_t *buf, int read_len)
+{   
+    uint8_t hmac_buf[SHA1_SIZE];
+    int hmac_offset;
+   
+    if (ssl->cipher_info->padding_size)
+    {
+        hmac_offset = read_len-buf[read_len-1]-ssl->cipher_info->digest_size-1;
+    }
+    else
+    {
+        hmac_offset = read_len - ssl->cipher_info->digest_size;
+    }
+
+    /* sanity check the offset */
+    if (hmac_offset < 0)
+    {
+        return SSL_ERROR_INVALID_HMAC;
+    }
+
+    ssl->hmac_header[3] = hmac_offset >> 8;      /* insert size */
+    ssl->hmac_header[4] = hmac_offset & 0xff;
+    add_hmac_digest(ssl, mode, ssl->hmac_header, buf, hmac_offset, hmac_buf);
+
+    if (memcmp(hmac_buf, &buf[hmac_offset], ssl->cipher_info->digest_size))
+    {
+        return SSL_ERROR_INVALID_HMAC;
+    }
+
+    return hmac_offset;
+}
+
+/**
+ * Add a packet to the end of our sent and received packets, so that we may use
+ * it to calculate the hash at the end.
+ */
+void add_packet(SSL *ssl, const uint8_t *pkt, int len)
+{
+    MD5_Update(&ssl->dc->md5_ctx, pkt, len);
+    SHA1_Update(&ssl->dc->sha1_ctx, pkt, len);
+}
+
+/**
+ * Work out the MD5 PRF.
+ */
+static void p_hash_md5(const uint8_t *sec, int sec_len, 
+        uint8_t *seed, int seed_len, uint8_t *out, int olen)
+{
+    uint8_t a1[128];
+
+    /* A(1) */
+    hmac_md5(seed, seed_len, sec, sec_len, a1);
+    memcpy(&a1[MD5_SIZE], seed, seed_len);
+    hmac_md5(a1, MD5_SIZE+seed_len, sec, sec_len, out);
+
+    while (olen > MD5_SIZE)
+    {
+        uint8_t a2[MD5_SIZE];
+        out += MD5_SIZE;
+        olen -= MD5_SIZE;
+
+        /* A(N) */
+        hmac_md5(a1, MD5_SIZE, sec, sec_len, a2);
+        memcpy(a1, a2, MD5_SIZE);
+
+        /* work out the actual hash */
+        hmac_md5(a1, MD5_SIZE+seed_len, sec, sec_len, out);
+    }
+}
+
+/**
+ * Work out the SHA1 PRF.
+ */
+static void p_hash_sha1(const uint8_t *sec, int sec_len, 
+        uint8_t *seed, int seed_len, uint8_t *out, int olen)
+{
+    uint8_t a1[128];
+
+    /* A(1) */
+    hmac_sha1(seed, seed_len, sec, sec_len, a1);
+    memcpy(&a1[SHA1_SIZE], seed, seed_len);
+    hmac_sha1(a1, SHA1_SIZE+seed_len, sec, sec_len, out);
+
+    while (olen > SHA1_SIZE)
+    {
+        uint8_t a2[SHA1_SIZE];
+        out += SHA1_SIZE;
+        olen -= SHA1_SIZE;
+
+        /* A(N) */
+        hmac_sha1(a1, SHA1_SIZE, sec, sec_len, a2);
+        memcpy(a1, a2, SHA1_SIZE);
+
+        /* work out the actual hash */
+        hmac_sha1(a1, SHA1_SIZE+seed_len, sec, sec_len, out);
+    }
+}
+
+/**
+ * Work out the PRF.
+ */
+static void prf(const uint8_t *sec, int sec_len, uint8_t *seed, int seed_len,
+        uint8_t *out, int olen)
+{
+    int len, i;
+    const uint8_t *S1, *S2;
+    uint8_t xbuf[256]; /* needs to be > the amount of key data */
+    uint8_t ybuf[256]; /* needs to be > the amount of key data */
+
+    len = sec_len/2;
+    S1 = sec;
+    S2 = &sec[len];
+    len += (sec_len & 1); /* add for odd, make longer */
+
+    p_hash_md5(S1, len, seed, seed_len, xbuf, olen);
+    p_hash_sha1(S2, len, seed, seed_len, ybuf, olen);
+
+    for (i = 0; i < olen; i++)
+        out[i] = xbuf[i] ^ ybuf[i];
+}
+
+/**
+ * Generate a master secret based on the client/server random data and the
+ * premaster secret.
+ */
+void generate_master_secret(SSL *ssl, const uint8_t *premaster_secret)
+{
+    uint8_t buf[128];   /* needs to be > 13+32+32 in size */
+    strcpy((char *)buf, "master secret");
+    memcpy(&buf[13], ssl->dc->client_random, SSL_RANDOM_SIZE);
+    memcpy(&buf[45], ssl->dc->server_random, SSL_RANDOM_SIZE);
+    prf(premaster_secret, SSL_SECRET_SIZE, buf, 77, ssl->dc->master_secret,
+            SSL_SECRET_SIZE);
+}
+
+/**
+ * Generate a 'random' blob of data used for the generation of keys.
+ */
+static void generate_key_block(uint8_t *client_random, uint8_t *server_random,
+        uint8_t *master_secret, uint8_t *key_block, int key_block_size)
+{
+    uint8_t buf[128];
+    strcpy((char *)buf, "key expansion");
+    memcpy(&buf[13], server_random, SSL_RANDOM_SIZE);
+    memcpy(&buf[45], client_random, SSL_RANDOM_SIZE);
+    prf(master_secret, SSL_SECRET_SIZE, buf, 77, key_block, key_block_size);
+}
+
+/** 
+ * Calculate the digest used in the finished message. This function also
+ * doubles up as a certificate verify function.
+ */
+void finished_digest(SSL *ssl, const char *label, uint8_t *digest)
+{
+    uint8_t mac_buf[128]; 
+    uint8_t *q = mac_buf;
+    MD5_CTX md5_ctx = ssl->dc->md5_ctx;
+    SHA1_CTX sha1_ctx = ssl->dc->sha1_ctx;
+
+    if (label)
+    {
+        strcpy((char *)q, label);
+        q += strlen(label);
+    }
+
+    MD5_Final(q, &md5_ctx);
+    q += MD5_SIZE;
+    
+    SHA1_Final(q, &sha1_ctx);
+    q += SHA1_SIZE;
+
+    if (label)
+    {
+        prf(ssl->dc->master_secret, SSL_SECRET_SIZE, mac_buf, (int)(q-mac_buf),
+            digest, SSL_FINISHED_HASH_SIZE);
+    }
+    else    /* for use in a certificate verify */
+    {
+        memcpy(digest, mac_buf, MD5_SIZE + SHA1_SIZE);
+    }
+
+#if 0
+    printf("label: %s\n", label);
+    print_blob("master secret", ssl->dc->master_secret, 48);
+    print_blob("mac_buf", mac_buf, q-mac_buf);
+    print_blob("finished digest", digest, SSL_FINISHED_HASH_SIZE);
+#endif
+}   
+    
+/**
+ * Retrieve (and initialise) the context of a cipher.
+ */
+static void *crypt_new(SSL *ssl, uint8_t *key, uint8_t *iv, int is_decrypt)
+{
+    switch (ssl->cipher)
+    {
+#ifndef CONFIG_SSL_SKELETON_MODE
+        case SSL_AES128_SHA:
+            {
+                AES_CTX *aes_ctx = (AES_CTX *)malloc(sizeof(AES_CTX));
+                AES_set_key(aes_ctx, key, iv, AES_MODE_128);
+
+                if (is_decrypt)
+                {
+                    AES_convert_key(aes_ctx);
+                }
+
+                return (void *)aes_ctx;
+            }
+
+        case SSL_AES256_SHA:
+            {
+                AES_CTX *aes_ctx = (AES_CTX *)malloc(sizeof(AES_CTX));
+                AES_set_key(aes_ctx, key, iv, AES_MODE_256);
+
+                if (is_decrypt)
+                {
+                    AES_convert_key(aes_ctx);
+                }
+
+                return (void *)aes_ctx;
+            }
+            break;
+
+        case SSL_RC4_128_MD5:
+#endif
+        case SSL_RC4_128_SHA:
+            {
+                RC4_CTX *rc4_ctx = (RC4_CTX *)malloc(sizeof(RC4_CTX));
+                RC4_setup(rc4_ctx, key, 16);
+                return (void *)rc4_ctx;
+            }
+            break;
+    }
+
+    return NULL;    /* its all gone wrong */
+}
+
+/**
+ * Send a packet over the socket.
+ */
+static int send_raw_packet(SSL *ssl, uint8_t protocol)
+{
+    uint8_t *rec_buf = ssl->bm_all_data;
+    int pkt_size = SSL_RECORD_SIZE+ssl->bm_index;
+    int sent = 0;
+    int ret = SSL_OK;
+
+    rec_buf[0] = protocol;
+    rec_buf[1] = 0x03;      /* version = 3.1 (TLS) */
+    rec_buf[2] = 0x01;
+    rec_buf[3] = ssl->bm_index >> 8;
+    rec_buf[4] = ssl->bm_index & 0xff;
+
+    DISPLAY_BYTES(ssl, "sending %d bytes", ssl->bm_all_data, 
+                             pkt_size, pkt_size);
+
+    while (sent < pkt_size)
+    {
+        if ((ret = SOCKET_WRITE(ssl->client_fd, 
+                        &ssl->bm_all_data[sent], pkt_size)) < 0)
+        {
+            ret = SSL_ERROR_CONN_LOST;
+            break;
+        }
+
+        sent += ret;
+
+        /* keep going until the write buffer has some space */
+        if (sent != pkt_size)
+        {
+            fd_set wfds;
+            FD_ZERO(&wfds);
+            FD_SET(ssl->client_fd, &wfds);
+
+            if (select(ssl->client_fd + 1, NULL, &wfds, NULL, NULL) < 0)
+            {
+                ret = SSL_ERROR_CONN_LOST;
+                break;
+            }
+        }
+    }
+
+    SET_SSL_FLAG(SSL_NEED_RECORD);  /* reset for next time */
+    ssl->bm_index = 0;
+
+    if (protocol != PT_APP_PROTOCOL_DATA)  
+    {
+        /* always return SSL_OK during handshake */   
+        ret = SSL_OK;
+    }
+
+    return ret;
+}
+
+/**
+ * Send an encrypted packet with padding bytes if necessary.
+ */
+int send_packet(SSL *ssl, uint8_t protocol, const uint8_t *in, int length)
+{
+    int msg_length = length;
+    int ret, pad_bytes = 0;
+    ssl->bm_index = msg_length;
+
+    /* if our state is bad, don't bother */
+    if (ssl->hs_status == SSL_ERROR_DEAD)
+        return SSL_ERROR_CONN_LOST;
+
+    if (in) /* has the buffer already been initialised? */
+    {
+        memcpy(ssl->bm_data, in, length);
+    }
+
+    if (IS_SET_SSL_FLAG(SSL_TX_ENCRYPTED))
+    {
+        int mode = IS_SET_SSL_FLAG(SSL_IS_CLIENT) ? 
+                            SSL_CLIENT_WRITE : SSL_SERVER_WRITE;
+        uint8_t hmac_header[SSL_RECORD_SIZE];
+
+        hmac_header[0] = protocol;
+        hmac_header[1] = 0x03;
+        hmac_header[2] = 0x01;
+        hmac_header[3] = length >> 8; 
+        hmac_header[4] = length & 0xff;
+
+        if (protocol == PT_HANDSHAKE_PROTOCOL)
+        {
+            DISPLAY_STATE(ssl, 1, ssl->bm_data[0], 0);
+
+            if (ssl->bm_data[0] != HS_HELLO_REQUEST)
+            {
+                add_packet(ssl, ssl->bm_data, ssl->bm_index);
+            }
+        }
+
+        /* add the packet digest */
+        msg_length += ssl->cipher_info->digest_size;
+        ssl->bm_index = msg_length;
+        add_hmac_digest(ssl, mode, hmac_header, ssl->bm_data, length, 
+                                                &ssl->bm_data[length]);
+
+        /* add padding? */
+        if (ssl->cipher_info->padding_size)
+        {
+            int last_blk_size = msg_length%ssl->cipher_info->padding_size;
+            pad_bytes = ssl->cipher_info->padding_size - last_blk_size;
+
+            /* ensure we always have at least 1 padding byte */
+            if (pad_bytes == 0)
+                pad_bytes += ssl->cipher_info->padding_size;
+
+            memset(&ssl->bm_data[msg_length], pad_bytes-1, pad_bytes);
+            msg_length += pad_bytes;
+            ssl->bm_index = msg_length;
+        }
+
+        DISPLAY_BYTES(ssl, "unencrypted write", ssl->bm_data, msg_length);
+        increment_write_sequence(ssl);
+
+        /* now encrypt the packet */
+        ssl->cipher_info->encrypt(ssl->encrypt_ctx, ssl->bm_data, 
+                                            ssl->bm_data, msg_length);
+    }
+    else if (protocol == PT_HANDSHAKE_PROTOCOL)
+    {
+        DISPLAY_STATE(ssl, 1, ssl->bm_data[0], 0);
+
+        if (ssl->bm_data[0] != HS_HELLO_REQUEST)
+        {
+            add_packet(ssl, ssl->bm_data, ssl->bm_index);
+        }
+    }
+
+    if ((ret = send_raw_packet(ssl, protocol)) <= 0)
+        return ret;
+
+    return length;  /* just return what we wanted to send */
+}
+
+/**
+ * Work out the cipher keys we are going to use for this session based on the
+ * master secret.
+ */
+static void set_key_block(SSL *ssl, int is_write)
+{
+    const cipher_info_t *ciph_info = get_cipher_info(ssl->cipher);
+    uint8_t *q;
+    uint8_t client_key[32], server_key[32]; /* big enough for AES256 */
+    uint8_t client_iv[16], server_iv[16];   /* big enough for AES128/256 */
+    int is_client = IS_SET_SSL_FLAG(SSL_IS_CLIENT);
+
+    /* only do once in a handshake */
+    if (ssl->dc->key_block == NULL)
+    {
+        ssl->dc->key_block = (uint8_t *)malloc(ciph_info->key_block_size);
+
+#if 0
+        print_blob("client", ssl->dc->client_random, 32);
+        print_blob("server", ssl->dc->server_random, 32);
+        print_blob("master", ssl->dc->master_secret, SSL_SECRET_SIZE);
+#endif
+        generate_key_block(ssl->dc->client_random, ssl->dc->server_random,
+            ssl->dc->master_secret, ssl->dc->key_block, 
+            ciph_info->key_block_size);
+#if 0
+        print_blob("keyblock", ssl->key_block, ciph_info->key_block_size);
+#endif
+    }
+
+    q = ssl->dc->key_block;
+
+    if ((is_client && is_write) || (!is_client && !is_write))
+    {
+        memcpy(ssl->client_mac, q, ciph_info->digest_size);
+    }
+
+    q += ciph_info->digest_size;
+
+    if ((!is_client && is_write) || (is_client && !is_write))
+    {
+        memcpy(ssl->server_mac, q, ciph_info->digest_size);
+    }
+
+    q += ciph_info->digest_size;
+    memcpy(client_key, q, ciph_info->key_size);
+    q += ciph_info->key_size;
+    memcpy(server_key, q, ciph_info->key_size);
+    q += ciph_info->key_size;
+
+#ifndef CONFIG_SSL_SKELETON_MODE 
+    if (ciph_info->iv_size)    /* RC4 has no IV, AES does */
+    {
+        memcpy(client_iv, q, ciph_info->iv_size);
+        q += ciph_info->iv_size;
+        memcpy(server_iv, q, ciph_info->iv_size);
+        q += ciph_info->iv_size;
+    }
+#endif
+
+    free(is_write ? ssl->encrypt_ctx : ssl->decrypt_ctx);
+
+    /* now initialise the ciphers */
+    if (is_client)
+    {
+        finished_digest(ssl, server_finished, ssl->dc->final_finish_mac);
+
+        if (is_write)
+            ssl->encrypt_ctx = crypt_new(ssl, client_key, client_iv, 0);
+        else
+            ssl->decrypt_ctx = crypt_new(ssl, server_key, server_iv, 1);
+    }
+    else
+    {
+        finished_digest(ssl, client_finished, ssl->dc->final_finish_mac);
+
+        if (is_write)
+            ssl->encrypt_ctx = crypt_new(ssl, server_key, server_iv, 0);
+        else
+            ssl->decrypt_ctx = crypt_new(ssl, client_key, client_iv, 1);
+    }
+
+    ssl->cipher_info = ciph_info;
+}
+
+/**
+ * Read the SSL connection.
+ */
+int basic_read(SSL *ssl, uint8_t **in_data)
+{
+    int ret = SSL_OK;
+    int read_len, is_client = IS_SET_SSL_FLAG(SSL_IS_CLIENT);
+    uint8_t *buf = ssl->bm_data;
+
+    read_len = SOCKET_READ(ssl->client_fd, &buf[ssl->bm_read_index], 
+                            ssl->need_bytes-ssl->got_bytes);
+
+    /* connection has gone, so die */
+    if (read_len <= 0)
+    {
+        ret = SSL_ERROR_CONN_LOST;
+        ssl->hs_status = SSL_ERROR_DEAD;  /* make sure it stays dead */
+        goto error;
+    }
+
+    DISPLAY_BYTES(ssl, "received %d bytes", 
+            &ssl->bm_data[ssl->bm_read_index], read_len, read_len);
+
+    ssl->got_bytes += read_len;
+    ssl->bm_read_index += read_len;
+
+    /* haven't quite got what we want, so try again later */
+    if (ssl->got_bytes < ssl->need_bytes)
+        return SSL_OK;
+
+    read_len = ssl->got_bytes;
+    ssl->got_bytes = 0;
+
+    if (IS_SET_SSL_FLAG(SSL_NEED_RECORD))
+    {
+        /* check for sslv2 "client hello" */
+        if (buf[0] & 0x80 && buf[2] == 1 && buf[3] == 0x03)
+        {
+#ifdef CONFIG_SSL_ENABLE_V23_HANDSHAKE
+            DISPLAY_BYTES(ssl, "ssl2 record", buf, 5);
+            add_packet(ssl, &buf[2], 3);
+            ret = process_sslv23_client_hello(ssl); 
+#else
+            printf("Error: no SSLv23 handshaking allowed\n"); TTY_FLUSH();
+            ret = SSL_ERROR_NOT_SUPPORTED;
+#endif
+            goto error; /* not an error - just get out of here */
+        }
+
+        ssl->need_bytes = (buf[3] << 8) + buf[4];
+
+        /* do we violate the spec with the message size?  */
+        if (ssl->need_bytes > RT_MAX_PLAIN_LENGTH+RT_EXTRA-BM_RECORD_OFFSET)
+        {
+            ret = SSL_ERROR_INVALID_PROT_MSG;              
+            goto error;
+        }
+
+        CLR_SSL_FLAG(SSL_NEED_RECORD);
+        memcpy(ssl->hmac_header, buf, 3);       /* store for hmac */
+        ssl->record_type = buf[0];
+        goto error;                         /* no error, we're done */
+    }
+
+    /* for next time - just do it now in case of an error */
+    SET_SSL_FLAG(SSL_NEED_RECORD);
+    ssl->need_bytes = SSL_RECORD_SIZE;
+
+    /* decrypt if we need to */
+    if (IS_SET_SSL_FLAG(SSL_RX_ENCRYPTED))
+    {
+        ssl->cipher_info->decrypt(ssl->decrypt_ctx, buf, buf, read_len);
+        read_len = verify_digest(ssl, 
+                is_client ? SSL_CLIENT_READ : SSL_SERVER_READ, buf, read_len);
+
+        /* does the hmac work? */
+        if (read_len < 0)
+        {
+            ret = read_len;
+            goto error;
+        }
+
+        DISPLAY_BYTES(ssl, "decrypted", buf, read_len);
+        increment_read_sequence(ssl);
+    }
+
+    /* The main part of the SSL packet */
+    switch (ssl->record_type)
+    {
+        case PT_HANDSHAKE_PROTOCOL:
+            ssl->dc->bm_proc_index = 0;
+            ret = do_handshake(ssl, buf, read_len);
+            break;
+
+        case PT_CHANGE_CIPHER_SPEC:
+            if (ssl->next_state != HS_FINISHED)
+            {
+                ret = SSL_ERROR_INVALID_HANDSHAKE;
+                goto error;
+            }
+
+            /* all encrypted from now on */
+            SET_SSL_FLAG(SSL_RX_ENCRYPTED);
+            set_key_block(ssl, 0);
+            memset(ssl->read_sequence, 0, 8);
+            break;
+
+        case PT_APP_PROTOCOL_DATA:
+            if (in_data)
+            {
+                *in_data = ssl->bm_data;   /* point to the work buffer */
+                (*in_data)[read_len] = 0;  /* null terminate just in case */
+            }
+
+            ret = read_len;
+            break;
+
+        case PT_ALERT_PROTOCOL:
+            /* return the alert # with alert bit set */
+            ret = -buf[1]; 
+            DISPLAY_ALERT(ssl, buf[1]);
+            break;
+
+        default:
+            ret = SSL_ERROR_INVALID_PROT_MSG;
+            break;
+    }
+
+error:
+    ssl->bm_read_index = 0;          /* reset to go again */
+
+    if (ret < SSL_OK && in_data)/* if all wrong, then clear this buffer ptr */
+        *in_data = NULL;
+
+    return ret;
+}
+
+/**
+ * Do some basic checking of data and then perform the appropriate handshaking.
+ */
+static int do_handshake(SSL *ssl, uint8_t *buf, int read_len)
+{
+    int hs_len = (buf[2]<<8) + buf[3];
+    uint8_t handshake_type = buf[0];
+    int ret = SSL_OK;
+    int is_client = IS_SET_SSL_FLAG(SSL_IS_CLIENT);
+
+    /* some integrity checking on the handshake */
+    PARANOIA_CHECK(read_len-SSL_HS_HDR_SIZE, hs_len);
+
+    if (handshake_type != ssl->next_state)
+    {
+        /* handle a special case on the client */
+        if (!is_client || handshake_type != HS_CERT_REQ ||
+                        ssl->next_state != HS_SERVER_HELLO_DONE)
+        {
+            ret = SSL_ERROR_INVALID_HANDSHAKE;
+            goto error;
+        }
+    }
+
+    hs_len += SSL_HS_HDR_SIZE;  /* adjust for when adding packets */
+    ssl->bm_index = hs_len;     /* store the size and check later */
+    DISPLAY_STATE(ssl, 0, handshake_type, 0);
+
+    if (handshake_type != HS_CERT_VERIFY && handshake_type != HS_HELLO_REQUEST)
+        add_packet(ssl, buf, hs_len); 
+
+#if defined(CONFIG_SSL_ENABLE_CLIENT)
+    ret = is_client ? 
+        do_clnt_handshake(ssl, handshake_type, buf, hs_len) :
+        do_svr_handshake(ssl, handshake_type, buf, hs_len);
+#else
+    ret = do_svr_handshake(ssl, handshake_type, buf, hs_len);
+#endif
+
+    /* just use recursion to get the rest */
+    if (hs_len < read_len && ret == SSL_OK)
+        ret = do_handshake(ssl, &buf[hs_len], read_len-hs_len);
+
+error:
+    return ret;
+}
+
+/**
+ * Sends the change cipher spec message. We have just read a finished message
+ * from the client.
+ */
+int send_change_cipher_spec(SSL *ssl)
+{
+    int ret = send_packet(ssl, PT_CHANGE_CIPHER_SPEC, 
+            g_chg_cipher_spec_pkt, sizeof(g_chg_cipher_spec_pkt));
+    SET_SSL_FLAG(SSL_TX_ENCRYPTED);
+    set_key_block(ssl, 1);
+    memset(ssl->write_sequence, 0, 8);
+    return ret;
+}
+
+/**
+ * Send a "finished" message
+ */
+int send_finished(SSL *ssl)
+{
+    uint8_t *buf = ssl->bm_data;
+
+    buf[0] = HS_FINISHED;
+    buf[1] = 0;
+    buf[2] = 0;
+    buf[3] = SSL_FINISHED_HASH_SIZE;
+
+    /* now add the finished digest mac (12 bytes) */
+    finished_digest(ssl, 
+        IS_SET_SSL_FLAG(SSL_IS_CLIENT) ?
+                    client_finished : server_finished, &buf[4]);
+
+#ifndef CONFIG_SSL_SKELETON_MODE
+    /* store in the session cache */
+    if (!IS_SET_SSL_FLAG(SSL_SESSION_RESUME) && ssl->ssl_ctx->num_sessions)
+    {
+        memcpy(ssl->session->master_secret,
+                ssl->dc->master_secret, SSL_SECRET_SIZE);
+    }
+#endif
+
+    return send_packet(ssl, PT_HANDSHAKE_PROTOCOL,
+                                NULL, SSL_FINISHED_HASH_SIZE+4);
+}
+
+/**
+ * Send an alert message.
+ * Return 1 if the alert was an "error".
+ */
+int send_alert(SSL *ssl, int error_code)
+{
+    int alert_num = 0;
+    int is_warning = 0;
+    uint8_t buf[2];
+
+    /* Don't bother we're already dead */
+    if (ssl->hs_status == SSL_ERROR_DEAD)
+    {
+        return SSL_ERROR_CONN_LOST;
+    }
+
+#ifdef CONFIG_SSL_FULL_MODE
+    if (IS_SET_SSL_FLAG(SSL_DISPLAY_STATES))
+        ssl_display_error(error_code);
+#endif
+
+    switch (error_code)
+    {
+        case SSL_ALERT_CLOSE_NOTIFY:
+            is_warning = 1;
+            alert_num = SSL_ALERT_CLOSE_NOTIFY;
+            break;
+
+        case SSL_ERROR_CONN_LOST:       /* don't send alert just yet */
+            is_warning = 1;
+            break;
+
+        case SSL_ERROR_INVALID_HANDSHAKE:
+        case SSL_ERROR_INVALID_PROT_MSG:
+            alert_num = SSL_ALERT_HANDSHAKE_FAILURE;
+            break;
+
+        case SSL_ERROR_INVALID_HMAC:
+        case SSL_ERROR_FINISHED_INVALID:
+            alert_num = SSL_ALERT_BAD_RECORD_MAC;
+            break;
+
+        case SSL_ERROR_INVALID_VERSION:
+            alert_num = SSL_ALERT_INVALID_VERSION;
+            break;
+
+        case SSL_ERROR_INVALID_SESSION:
+        case SSL_ERROR_NO_CIPHER:
+        case SSL_ERROR_INVALID_KEY:
+            alert_num = SSL_ALERT_ILLEGAL_PARAMETER;
+            break;
+
+        case SSL_ERROR_BAD_CERTIFICATE:
+            alert_num = SSL_ALERT_BAD_CERTIFICATE;
+            break;
+
+        default:
+            /* a catch-all for any badly verified certificates */
+            alert_num = (error_code <= SSL_X509_OFFSET) ?  
+                SSL_ALERT_BAD_CERTIFICATE : SSL_ALERT_UNEXPECTED_MESSAGE;
+            break;
+    }
+
+    buf[0] = is_warning ? 1 : 2;
+    buf[1] = alert_num;
+    send_packet(ssl, PT_ALERT_PROTOCOL, buf, sizeof(buf));
+    DISPLAY_ALERT(ssl, alert_num);
+    return is_warning ? 0 : 1;
+}
+
+/**
+ * Process a client finished message.
+ */
+int process_finished(SSL *ssl, int hs_len)
+{
+    uint8_t *buf = ssl->bm_data;
+    int ret = SSL_OK;
+    int is_client = IS_SET_SSL_FLAG(SSL_IS_CLIENT);
+    int resume = IS_SET_SSL_FLAG(SSL_SESSION_RESUME);
+
+    PARANOIA_CHECK(ssl->bm_index, SSL_FINISHED_HASH_SIZE+4);
+
+    /* check that we all work before we continue */
+    if (memcmp(ssl->dc->final_finish_mac, &buf[4], SSL_FINISHED_HASH_SIZE))
+        return SSL_ERROR_FINISHED_INVALID;
+
+    if ((!is_client && !resume) || (is_client && resume))
+    {
+        if ((ret = send_change_cipher_spec(ssl)) == SSL_OK)
+            ret = send_finished(ssl);
+    }
+
+    /* if we ever renegotiate */
+    ssl->next_state = is_client ? HS_HELLO_REQUEST : HS_CLIENT_HELLO;  
+    ssl->hs_status = ret;  /* set the final handshake status */
+
+error:
+    return ret;
+}
+
+/**
+ * Send a certificate.
+ */
+int send_certificate(SSL *ssl)
+{
+    int i = 0;
+    uint8_t *buf = ssl->bm_data;
+    int offset = 7;
+    int chain_length;
+
+    buf[0] = HS_CERTIFICATE;
+    buf[1] = 0;
+    buf[4] = 0;
+
+    while (i < ssl->ssl_ctx->chain_length)
+    {
+        SSL_CERT *cert = &ssl->ssl_ctx->certs[i];
+        buf[offset++] = 0;        
+        buf[offset++] = cert->size >> 8;        /* cert 1 length */
+        buf[offset++] = cert->size & 0xff;
+        memcpy(&buf[offset], cert->buf, cert->size);
+        offset += cert->size;
+        i++;
+    }
+
+    chain_length = offset - 7;
+    buf[5] = chain_length >> 8;        /* cert chain length */
+    buf[6] = chain_length & 0xff;
+    chain_length += 3;
+    buf[2] = chain_length >> 8;        /* handshake length */
+    buf[3] = chain_length & 0xff;
+    ssl->bm_index = offset;
+    return send_packet(ssl, PT_HANDSHAKE_PROTOCOL, NULL, offset);
+}
+
+/**
+ * Create a blob of memory that we'll get rid of once the handshake is
+ * complete.
+ */
+void disposable_new(SSL *ssl)
+{
+    if (ssl->dc == NULL)
+    {
+        ssl->dc = (DISPOSABLE_CTX *)calloc(1, sizeof(DISPOSABLE_CTX));
+        MD5_Init(&ssl->dc->md5_ctx);
+        SHA1_Init(&ssl->dc->sha1_ctx);
+    }
+}
+
+/**
+ * Remove the temporary blob of memory.
+ */
+void disposable_free(SSL *ssl)
+{
+    if (ssl->dc)
+    {
+	    free(ssl->dc->key_block);
+        memset(ssl->dc, 0, sizeof(DISPOSABLE_CTX));
+        free(ssl->dc);
+        ssl->dc = NULL;
+    }
+
+}
+
+#ifndef CONFIG_SSL_SKELETON_MODE     /* no session resumption in this mode */
+/**
+ * Find if an existing session has the same session id. If so, use the
+ * master secret from this session for session resumption.
+ */
+SSL_SESSION *ssl_session_update(int max_sessions, SSL_SESSION *ssl_sessions[], 
+        SSL *ssl, const uint8_t *session_id)
+{
+    time_t tm = time(NULL);
+    time_t oldest_sess_time = tm;
+    SSL_SESSION *oldest_sess = NULL;
+    int i;
+
+    /* no sessions? Then bail */
+    if (max_sessions == 0)
+        return NULL;
+
+    SSL_CTX_LOCK(ssl->ssl_ctx->mutex);
+    if (session_id)
+    {
+        for (i = 0; i < max_sessions; i++)
+        {
+            if (ssl_sessions[i])
+            {
+                /* kill off any expired sessions */
+                if (tm > ssl_sessions[i]->conn_time + SSL_EXPIRY_TIME)
+                {
+                    session_free(ssl_sessions, i);
+                    continue;
+                }
+
+                /* if the session id matches, it must still be less than 
+                   the expiry time */
+                if (memcmp(ssl_sessions[i]->session_id, session_id,
+                                                SSL_SESSION_ID_SIZE) == 0)
+                {
+                    ssl->session_index = i;
+                    memcpy(ssl->dc->master_secret, 
+                            ssl_sessions[i]->master_secret, SSL_SECRET_SIZE);
+                    SET_SSL_FLAG(SSL_SESSION_RESUME);
+                    SSL_CTX_UNLOCK(ssl->ssl_ctx->mutex);
+                    return ssl_sessions[i];  /* a session was found */
+                }
+            }
+        }
+    }
+
+    /* If we've got here, no matching session was found - so create one */
+    for (i = 0; i < max_sessions; i++)
+    {
+        if (ssl_sessions[i] == NULL)
+        {
+            /* perfect, this will do */
+            ssl_sessions[i] = (SSL_SESSION *)calloc(1, sizeof(SSL_SESSION));
+            ssl_sessions[i]->conn_time = tm;
+            ssl->session_index = i;
+            SSL_CTX_UNLOCK(ssl->ssl_ctx->mutex);
+            return ssl_sessions[i]; /* return the session object */
+        }
+        else if (ssl_sessions[i]->conn_time <= oldest_sess_time)
+        {
+            /* find the oldest session */
+            oldest_sess_time = ssl_sessions[i]->conn_time;
+            oldest_sess = ssl_sessions[i];
+            ssl->session_index = i;
+        }
+    }
+
+    /* ok, we've used up all of our sessions. So blow the oldest session away */
+    oldest_sess->conn_time = tm;
+    memset(oldest_sess->session_id, 0, sizeof(SSL_SESSION_ID_SIZE));
+    memset(oldest_sess->master_secret, 0, sizeof(SSL_SECRET_SIZE));
+    SSL_CTX_UNLOCK(ssl->ssl_ctx->mutex);
+    return oldest_sess;
+}
+
+/**
+ * Free an existing session.
+ */
+static void session_free(SSL_SESSION *ssl_sessions[], int sess_index)
+{
+    if (ssl_sessions[sess_index])
+    {
+        free(ssl_sessions[sess_index]);
+        ssl_sessions[sess_index] = NULL;
+    }
+}
+
+/**
+ * This ssl object doesn't want this session anymore.
+ */
+void kill_ssl_session(SSL_SESSION **ssl_sessions, SSL *ssl)
+{
+    SSL_CTX_LOCK(ssl->ssl_ctx->mutex);
+
+    if (ssl->ssl_ctx->num_sessions)
+    {
+        session_free(ssl_sessions, ssl->session_index);
+        ssl->session = NULL;
+    }
+
+    SSL_CTX_UNLOCK(ssl->ssl_ctx->mutex);
+}
+#endif /* CONFIG_SSL_SKELETON_MODE */
+
+/*
+ * Get the session id for a handshake. This will be a 32 byte sequence.
+ */
+EXP_FUNC const uint8_t * STDCALL ssl_get_session_id(const SSL *ssl)
+{
+    return ssl->session_id;
+}
+
+/*
+ * Get the session id size for a handshake. 
+ */
+EXP_FUNC uint8_t STDCALL ssl_get_session_id_size(const SSL *ssl)
+{
+    return ssl->sess_id_size;
+}
+
+/*
+ * Return the cipher id (in the SSL form).
+ */
+EXP_FUNC uint8_t STDCALL ssl_get_cipher_id(const SSL *ssl)
+{
+    return ssl->cipher;
+}
+
+/*
+ * Return the status of the handshake.
+ */
+EXP_FUNC int STDCALL ssl_handshake_status(const SSL *ssl)
+{
+    return ssl->hs_status;
+}
+
+/*
+ * Retrieve various parameters about the SSL engine.
+ */
+EXP_FUNC int STDCALL ssl_get_config(int offset)
+{
+    switch (offset)
+    {
+        /* return the appropriate build mode */
+        case SSL_BUILD_MODE:
+#if defined(CONFIG_SSL_FULL_MODE)
+            return SSL_BUILD_FULL_MODE;
+#elif defined(CONFIG_SSL_ENABLE_CLIENT)
+            return SSL_BUILD_ENABLE_CLIENT;
+#elif defined(CONFIG_ENABLE_VERIFICATION)
+            return SSL_BUILD_ENABLE_VERIFICATION;
+#elif defined(CONFIG_SSL_SERVER_ONLY )
+            return SSL_BUILD_SERVER_ONLY;
+#else 
+            return SSL_BUILD_SKELETON_MODE;
+#endif
+
+        case SSL_MAX_CERT_CFG_OFFSET:
+            return CONFIG_SSL_MAX_CERTS;
+
+#ifdef CONFIG_SSL_CERT_VERIFICATION
+        case SSL_MAX_CA_CERT_CFG_OFFSET:
+            return CONFIG_X509_MAX_CA_CERTS;
+#endif
+#ifdef CONFIG_SSL_HAS_PEM
+        case SSL_HAS_PEM:
+            return 1;
+#endif
+        default:
+            return 0;
+    }
+}
+
+#ifdef CONFIG_SSL_CERT_VERIFICATION
+/**
+ * Authenticate a received certificate.
+ */
+EXP_FUNC int STDCALL ssl_verify_cert(const SSL *ssl)
+{
+    int ret;
+    SSL_CTX_LOCK(ssl->ssl_ctx->mutex);
+    ret = x509_verify(ssl->ssl_ctx->ca_cert_ctx, ssl->x509_ctx);
+    SSL_CTX_UNLOCK(ssl->ssl_ctx->mutex);
+
+    if (ret)        /* modify into an SSL error type */
+    {
+        ret = SSL_X509_ERROR(ret);
+    }
+
+    return ret;
+}
+
+/**
+ * Process a certificate message.
+ */
+int process_certificate(SSL *ssl, X509_CTX **x509_ctx)
+{
+    int ret = SSL_OK;
+    uint8_t *buf = &ssl->bm_data[ssl->dc->bm_proc_index];
+    int pkt_size = ssl->bm_index;
+    int cert_size, offset = 5;
+    int total_cert_size = (buf[offset]<<8) + buf[offset+1];
+    int is_client = IS_SET_SSL_FLAG(SSL_IS_CLIENT);
+    X509_CTX **chain = x509_ctx;
+    offset += 2;
+
+    PARANOIA_CHECK(total_cert_size, offset);
+
+    while (offset < total_cert_size)
+    {
+        offset++;       /* skip empty char */
+        cert_size = (buf[offset]<<8) + buf[offset+1];
+        offset += 2;
+        
+        if (x509_new(&buf[offset], NULL, chain))
+        {
+            ret = SSL_ERROR_BAD_CERTIFICATE;
+            goto error;
+        }
+
+        /* DISPLAY_CERT(ssl, *chain); */
+        chain = &((*chain)->next);
+        offset += cert_size;
+    }
+
+    PARANOIA_CHECK(pkt_size, offset);
+
+    /* if we are client we can do the verify now or later */
+    if (is_client && !IS_SET_SSL_FLAG(SSL_SERVER_VERIFY_LATER))
+    {
+        ret = ssl_verify_cert(ssl);
+    }
+
+    ssl->next_state = is_client ? HS_SERVER_HELLO_DONE : HS_CLIENT_KEY_XCHG;
+    ssl->dc->bm_proc_index += offset;
+error:
+    return ret;
+}
+
+#endif /* CONFIG_SSL_CERT_VERIFICATION */
+
+/**
+ * Debugging routine to display SSL handshaking stuff.
+ */
+#ifdef CONFIG_SSL_FULL_MODE
+/**
+ * Debugging routine to display SSL states.
+ */
+void DISPLAY_STATE(SSL *ssl, int is_send, uint8_t state, int not_ok)
+{
+    const char *str;
+
+    if (!IS_SET_SSL_FLAG(SSL_DISPLAY_STATES))
+        return;
+
+    printf(not_ok ? "Error - invalid State:\t" : "State:\t");
+    printf(is_send ? "sending " : "receiving ");
+
+    switch (state)
+    {
+        case HS_HELLO_REQUEST:
+            str = "Hello Request (0)";
+            break;
+
+        case HS_CLIENT_HELLO:
+            str = "Client Hello (1)";
+            break;
+
+        case HS_SERVER_HELLO:
+            str = "Server Hello (2)";
+            break;
+
+        case HS_CERTIFICATE:
+            str = "Certificate (11)";
+            break;
+
+        case HS_SERVER_KEY_XCHG:
+            str = "Certificate Request (12)";
+            break;
+
+        case HS_CERT_REQ:
+            str = "Certificate Request (13)";
+            break;
+
+        case HS_SERVER_HELLO_DONE:
+            str = "Server Hello Done (14)";
+            break;
+
+        case HS_CERT_VERIFY:
+            str = "Certificate Verify (15)";
+            break;
+
+        case HS_CLIENT_KEY_XCHG:
+            str = "Client Key Exchange (16)";
+            break;
+
+        case HS_FINISHED:
+            str = "Finished (16)";
+            break;
+
+        default:
+            str = "Error (Unknown)";
+            
+            break;
+    }
+
+    printf("%s\n", str);
+    TTY_FLUSH();
+}
+
+/**
+ * Debugging routine to display X509 certificates.
+ */
+void DISPLAY_CERT(SSL *ssl, const X509_CTX *x509_ctx)
+{
+    if (!IS_SET_SSL_FLAG(SSL_DISPLAY_CERTS))
+        return;
+
+    x509_print(x509_ctx, ssl->ssl_ctx->ca_cert_ctx);
+    TTY_FLUSH();
+}
+
+/**
+ * Debugging routine to display RSA objects
+ */
+void DISPLAY_RSA(SSL *ssl, const RSA_CTX *rsa_ctx)
+{
+    if (!IS_SET_SSL_FLAG(SSL_DISPLAY_RSA))
+        return;
+
+    RSA_print(rsa_ctx);
+    TTY_FLUSH();
+}
+
+/**
+ * Debugging routine to display SSL handshaking bytes.
+ */
+void DISPLAY_BYTES(SSL *ssl, const char *format, 
+        const uint8_t *data, int size, ...)
+{
+    va_list(ap);
+
+    if (!IS_SET_SSL_FLAG(SSL_DISPLAY_BYTES))
+        return;
+
+    va_start(ap, size);
+    print_blob(format, data, size, va_arg(ap, char *));
+    va_end(ap);
+    TTY_FLUSH();
+}
+
+/**
+ * Debugging routine to display SSL handshaking errors.
+ */
+EXP_FUNC void STDCALL ssl_display_error(int error_code)
+{
+    if (error_code == SSL_OK)
+        return;
+
+    printf("Error: ");
+
+    /* X509 error? */
+    if (error_code < SSL_X509_OFFSET)
+    {
+        printf("%s\n", x509_display_error(error_code - SSL_X509_OFFSET));
+        return;
+    }
+
+    /* SSL alert error code */
+    if (error_code > SSL_ERROR_CONN_LOST)
+    {
+        printf("SSL error %d\n", -error_code);
+        return;
+    }
+
+    switch (error_code)
+    {
+        case SSL_ERROR_DEAD:
+            printf("connection dead");
+            break;
+
+        case SSL_ERROR_INVALID_HANDSHAKE:
+            printf("invalid handshake");
+            break;
+
+        case SSL_ERROR_INVALID_PROT_MSG:
+            printf("invalid protocol message");
+            break;
+
+        case SSL_ERROR_INVALID_HMAC:
+            printf("invalid mac");
+            break;
+
+        case SSL_ERROR_INVALID_VERSION:
+            printf("invalid version");
+            break;
+
+        case SSL_ERROR_INVALID_SESSION:
+            printf("invalid session");
+            break;
+
+        case SSL_ERROR_NO_CIPHER:
+            printf("no cipher");
+            break;
+
+        case SSL_ERROR_CONN_LOST:
+            printf("connection lost");
+            break;
+
+        case SSL_ERROR_BAD_CERTIFICATE:
+            printf("bad certificate");
+            break;
+
+        case SSL_ERROR_INVALID_KEY:
+            printf("invalid key");
+            break;
+
+        case SSL_ERROR_FINISHED_INVALID:
+            printf("finished invalid");
+            break;
+
+        case SSL_ERROR_NO_CERT_DEFINED:
+            printf("no certificate defined");
+            break;
+
+        case SSL_ERROR_NOT_SUPPORTED:
+            printf("Option not supported");
+            break;
+
+        default:
+            printf("undefined as yet - %d", error_code);
+            break;
+    }
+
+    printf("\n");
+    TTY_FLUSH();
+}
+
+/**
+ * Debugging routine to display alerts.
+ */
+void DISPLAY_ALERT(SSL *ssl, int alert)
+{
+    if (!IS_SET_SSL_FLAG(SSL_DISPLAY_STATES))
+        return;
+
+    printf("Alert: ");
+
+    switch (alert)
+    {
+        case SSL_ALERT_CLOSE_NOTIFY:
+            printf("close notify");
+            break;
+
+        case SSL_ALERT_INVALID_VERSION:
+            printf("invalid version");
+            break;
+
+        case SSL_ALERT_BAD_CERTIFICATE:
+            printf("bad certificate");
+            break;
+
+        case SSL_ALERT_UNEXPECTED_MESSAGE:
+            printf("unexpected message");
+            break;
+
+        case SSL_ALERT_BAD_RECORD_MAC:
+            printf("bad record mac");
+            break;
+
+        case SSL_ALERT_HANDSHAKE_FAILURE:
+            printf("handshake failure");
+            break;
+
+        case SSL_ALERT_ILLEGAL_PARAMETER:
+            printf("illegal parameter");
+            break;
+
+        case SSL_ALERT_DECODE_ERROR:
+            printf("decode error");
+            break;
+
+        case SSL_ALERT_DECRYPT_ERROR:
+            printf("decrypt error");
+            break;
+
+        default:
+            printf("alert - (unknown %d)", alert);
+            break;
+    }
+
+    printf("\n");
+    TTY_FLUSH();
+}
+
+#endif /* CONFIG_SSL_FULL_MODE */
+
+/**
+ * Return the version of this library.
+ */
+EXP_FUNC const char  * STDCALL ssl_version()
+{
+    static const char * axtls_version = AXTLS_VERSION;
+    return axtls_version;
+}
+
+/**
+ * Enable the various language bindings to work regardless of the
+ * configuration - they just return an error statement and a bad return code.
+ */
+#if !defined(CONFIG_SSL_FULL_MODE)
+EXP_FUNC void STDCALL ssl_display_error(int error_code) {}
+#endif
+
+#ifdef CONFIG_BINDINGS
+#if !defined(CONFIG_SSL_ENABLE_CLIENT)
+EXP_FUNC SSL * STDCALL ssl_client_new(SSL_CTX *ssl_ctx, int client_fd, const
+        uint8_t *session_id, uint8_t sess_id_size)
+{
+    printf(unsupported_str);
+    return NULL;
+}
+#endif
+
+#if !defined(CONFIG_SSL_CERT_VERIFICATION)
+EXP_FUNC int STDCALL ssl_verify_cert(const SSL *ssl)
+{
+    printf(unsupported_str);
+    return -1;
+}
+
+EXP_FUNC const char * STDCALL ssl_get_cert_dn(const SSL *ssl, int component)
+{
+    printf(unsupported_str);
+    return NULL;
+}
+
+#endif  /* CONFIG_SSL_CERT_VERIFICATION */
+
+#endif /* CONFIG_BINDINGS */
+