Consolidate common parts of setup_esp_keys()

There was a fair amount of redundancy between the OpenSSL and GnuTLS
variants. Create a new common function for that instead.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>

diff --git a/esp.c b/esp.c
index 2a4d1b60888f6555b6c5df77d5b83e3c96f0fc3e..1b907435b56f13275685d75b55d8636b4ffed688 100644 (file)
--- a/esp.c
+++ b/esp.c
@@ -347,3 +347,52 @@ void esp_shutdown(struct openconnect_info *vpninfo)
        if (vpninfo->dtls_state != DTLS_DISABLED)
                vpninfo->dtls_state = DTLS_NOSECRET;
 }
+
+int openconnect_setup_esp_keys(struct openconnect_info *vpninfo, int new_keys)
+{
+       struct esp *esp_in;
+       int ret;
+
+       if (vpninfo->dtls_state == DTLS_DISABLED)
+               return -EOPNOTSUPP;
+       if (!vpninfo->dtls_addr)
+               return -EINVAL;
+
+       if (new_keys) {
+               vpninfo->old_esp_maxseq = vpninfo->esp_in[vpninfo->current_esp_in].seq + 32;
+               vpninfo->current_esp_in ^= 1;
+       }
+
+       esp_in = &vpninfo->esp_in[vpninfo->current_esp_in];
+
+       if (new_keys) {
+               if (openconnect_random(&esp_in->spi, sizeof(esp_in->spi)) ||
+                   openconnect_random((void *)&esp_in->enc_key, vpninfo->enc_key_len) ||
+                   openconnect_random((void *)&esp_in->hmac_key, vpninfo->hmac_key_len)) {
+                       vpn_progress(vpninfo, PRG_ERR,
+                                    _("Failed to generate random keys for ESP\n"));
+                       return -EIO;
+               }
+       }
+
+       if (openconnect_random(vpninfo->esp_out.iv, sizeof(vpninfo->esp_out.iv))) {
+               vpn_progress(vpninfo, PRG_ERR,
+                            _("Failed to generate initial IV for ESP\n"));
+               return -EIO;
+       }
+
+       /* This is the minimum; some implementations may increase it */
+       vpninfo->pkt_trailer = 17 + 16 + 20; /* 17 for pad, 16 for IV, 20 for HMAC (of which we send 12) */
+
+       vpninfo->esp_out.seq = vpninfo->esp_out.seq_backlog = 0;
+       esp_in->seq = esp_in->seq_backlog = 0;
+
+       ret = init_esp_ciphers(vpninfo, &vpninfo->esp_out, esp_in);
+       if (ret)
+               return ret;
+
+       if (vpninfo->dtls_state == DTLS_NOSECRET)
+               vpninfo->dtls_state = DTLS_SECRET;
+
+       return 0;
+}

diff --git a/gnutls-esp.c b/gnutls-esp.c
index d8a8d7c07edf0c9fb3a453374f032adb430daac7..08adc11501167b15bddd4548a8af4bca2bb05230 100644 (file)
--- a/gnutls-esp.c
+++ b/gnutls-esp.c
@@ -39,8 +39,8 @@ void destroy_esp_ciphers(struct esp *esp)
        }
 }
 
-static int init_esp_ciphers(struct openconnect_info *vpninfo, struct esp *esp,
-                           gnutls_mac_algorithm_t macalg, gnutls_cipher_algorithm_t encalg)
+static int init_esp_cipher(struct openconnect_info *vpninfo, struct esp *esp,
+                          gnutls_mac_algorithm_t macalg, gnutls_cipher_algorithm_t encalg)
 {
        gnutls_datum_t enc_key;
        int err;
@@ -67,28 +67,20 @@ static int init_esp_ciphers(struct openconnect_info *vpninfo, struct esp *esp,
                             gnutls_strerror(err));
                destroy_esp_ciphers(esp);
        }
-       esp->seq = 0;
-       esp->seq_backlog = 0;
        return 0;
 }
 
-int setup_esp_keys(struct openconnect_info *vpninfo, int new_keys)
+int init_esp_ciphers(struct openconnect_info *vpninfo, struct esp *esp_out, struct esp *esp_in)
 {
-       struct esp *esp_in;
        gnutls_mac_algorithm_t macalg;
        gnutls_cipher_algorithm_t encalg;
        int ret;
 
-       if (vpninfo->dtls_state == DTLS_DISABLED)
-               return -EOPNOTSUPP;
-       if (!vpninfo->dtls_addr)
-               return -EINVAL;
-
        switch (vpninfo->esp_enc) {
-       case 0x02:
+       case ENC_AES_128_CBC:
                encalg = GNUTLS_CIPHER_AES_128_CBC;
                break;
-       case 0x05:
+       case ENC_AES_256_CBC:
                encalg = GNUTLS_CIPHER_AES_256_CBC;
                break;
        default:
@@ -96,56 +88,28 @@ int setup_esp_keys(struct openconnect_info *vpninfo, int new_keys)
        }
 
        switch (vpninfo->esp_hmac) {
-       case 0x01:
+       case HMAC_MD5:
                macalg = GNUTLS_MAC_MD5;
                break;
-       case 0x02:
+       case HMAC_SHA1:
                macalg = GNUTLS_MAC_SHA1;
                break;
        default:
                return -EINVAL;
        }
 
-       if (new_keys) {
-               vpninfo->old_esp_maxseq = vpninfo->esp_in[vpninfo->current_esp_in].seq + 32;
-               vpninfo->current_esp_in ^= 1;
-       }
-
-       esp_in = &vpninfo->esp_in[vpninfo->current_esp_in];
-
-       if (new_keys) {
-               if ((ret = gnutls_rnd(GNUTLS_RND_NONCE, &esp_in->spi, sizeof(esp_in->spi))) ||
-                   (ret = gnutls_rnd(GNUTLS_RND_RANDOM, &esp_in->enc_key, vpninfo->enc_key_len)) ||
-                   (ret = gnutls_rnd(GNUTLS_RND_RANDOM, &esp_in->hmac_key, vpninfo->hmac_key_len)) ) {
-                       vpn_progress(vpninfo, PRG_ERR,
-                                    _("Failed to generate random keys for ESP: %s\n"),
-                                    gnutls_strerror(ret));
-                       return -EIO;
-               }
-       }
-
-       ret = init_esp_ciphers(vpninfo, &vpninfo->esp_out, macalg, encalg);
+       ret = init_esp_cipher(vpninfo, esp_out, macalg, encalg);
        if (ret)
                return ret;
 
-       if (gnutls_rnd(GNUTLS_RND_NONCE, vpninfo->esp_out.iv, sizeof(vpninfo->esp_out.iv))) {
-               vpn_progress(vpninfo, PRG_ERR, _("Failed to generate ESP IV\n"));
-               destroy_esp_ciphers(&vpninfo->esp_out);
-               return -EIO;
-       }
-       gnutls_cipher_set_iv(vpninfo->esp_out.cipher, vpninfo->esp_out.iv,
-                            sizeof(vpninfo->esp_out.iv));
-
+       gnutls_cipher_set_iv(esp_out->cipher, esp_out->iv, sizeof(esp_out->iv));
 
-       ret = init_esp_ciphers(vpninfo, esp_in, macalg, encalg);
+       ret = init_esp_cipher(vpninfo, esp_in, macalg, encalg);
        if (ret) {
-               destroy_esp_ciphers(&vpninfo->esp_out);
+               destroy_esp_ciphers(esp_out);
                return ret;
        }
 
-       if (vpninfo->dtls_state == DTLS_NOSECRET)
-               vpninfo->dtls_state = DTLS_SECRET;
-       vpninfo->pkt_trailer = 16 + 20; /* 16 for pad, 20 for HMAC (of which we use 16) */
        return 0;
 }
 

diff --git a/gpst.c b/gpst.c
index 80af5f09350892162c218b1785c759a329eaa37b..96efa11be326765267d081768bd13d351ec50b94 100644 (file)
--- a/gpst.c
+++ b/gpst.c
@@ -550,7 +550,7 @@ static int gpst_parse_config_xml(struct openconnect_info *vpninfo, xmlNode *xml_
                                        else if (!xmlnode_get_val(member, "ipsec-mode", &s) && strcmp(s, "esp-tunnel"))
                                                vpn_progress(vpninfo, PRG_ERR, _("GlobalProtect config sent ipsec-mode=%s (expected esp-tunnel)\n"), s);
                                }
-                               if (setup_esp_keys(vpninfo, 0))
+                               if (openconnect_setup_esp_keys(vpninfo, 0))
                                        vpn_progress(vpninfo, PRG_ERR, "Failed to setup ESP keys.\n");
                                else
                                        /* prevent race condition between esp_mainloop() and gpst_mainloop() timers */

diff --git a/oncp.c b/oncp.c
index 4c389f5a749d75794e892ca880dfb801c0d53325..24b1e56cef010dd79529a5c91ca7d0abe2e043df 100644 (file)
--- a/oncp.c
+++ b/oncp.c
@@ -752,7 +752,7 @@ int oncp_connect(struct openconnect_info *vpninfo)
        put_len16(reqbuf, kmp);
 
 #ifdef HAVE_ESP
-       if (!setup_esp_keys(vpninfo, 1)) {
+       if (!openconnect_setup_esp_keys(vpninfo, 1)) {
                struct esp *esp = &vpninfo->esp_in[vpninfo->current_esp_in];
                /* Since we'll want to do this in the oncp_mainloop too, where it's easier
                 * *not* to have an oc_text_buf and build it up manually, and since it's
@@ -806,7 +806,7 @@ static int oncp_receive_espkeys(struct openconnect_info *vpninfo, int len)
        int ret;
 
        ret = parse_conf_pkt(vpninfo, vpninfo->cstp_pkt->oncp.kmp, len + 20, 301);
-       if (!ret && !setup_esp_keys(vpninfo, 1)) {
+       if (!ret && !openconnect_setup_esp_keys(vpninfo, 1)) {
                struct esp *esp = &vpninfo->esp_in[vpninfo->current_esp_in];
                unsigned char *p = vpninfo->cstp_pkt->oncp.kmp;
 

diff --git a/openconnect-internal.h b/openconnect-internal.h
index 6304084b7462ef8ee2cbe4c8fd215e8304a6a260..b7ac3ba92313a71e50851bd8be8e4d37dea45874 100644 (file)
--- a/openconnect-internal.h
+++ b/openconnect-internal.h
@@ -930,10 +930,11 @@ int esp_mainloop(struct openconnect_info *vpninfo, int *timeout, int readable);
 void esp_close(struct openconnect_info *vpninfo);
 void esp_shutdown(struct openconnect_info *vpninfo);
 int print_esp_keys(struct openconnect_info *vpninfo, const char *name, struct esp *esp);
+int openconnect_setup_esp_keys(struct openconnect_info *vpninfo, int new_keys);
 
 /* {gnutls,openssl}-esp.c */
-int setup_esp_keys(struct openconnect_info *vpninfo, int new_keys);
 void destroy_esp_ciphers(struct esp *esp);
+int init_esp_ciphers(struct openconnect_info *vpninfo, struct esp *out, struct esp *in);
 int decrypt_esp_packet(struct openconnect_info *vpninfo, struct esp *esp, struct pkt *pkt);
 int encrypt_esp_packet(struct openconnect_info *vpninfo, struct pkt *pkt);
 

diff --git a/openssl-esp.c b/openssl-esp.c
index 9f6531c2dcb50bf5da824b07f613efaba077de1a..364bb283161bbcf967667be07451f392157ef84b 100644 (file)
--- a/openssl-esp.c
+++ b/openssl-esp.c
@@ -57,7 +57,7 @@ void destroy_esp_ciphers(struct esp *esp)
        }
 }
 
-static int init_esp_ciphers(struct openconnect_info *vpninfo, struct esp *esp,
+static int init_esp_cipher(struct openconnect_info *vpninfo, struct esp *esp,
                            const EVP_MD *macalg, const EVP_CIPHER *encalg, int decrypt)
 {
        int ret;
@@ -78,8 +78,7 @@ static int init_esp_ciphers(struct openconnect_info *vpninfo, struct esp *esp,
        if (decrypt)
                ret = EVP_DecryptInit_ex(esp->cipher, encalg, NULL, esp->enc_key, NULL);
        else {
-               ret = RAND_bytes((void *)&esp->iv, sizeof(esp->iv)) &&
-                       EVP_EncryptInit_ex(esp->cipher, encalg, NULL, esp->enc_key, esp->iv);
+               ret = EVP_EncryptInit_ex(esp->cipher, encalg, NULL, esp->enc_key, esp->iv);
        }
 
        if (!ret) {
@@ -103,28 +102,21 @@ static int init_esp_ciphers(struct openconnect_info *vpninfo, struct esp *esp,
                openconnect_report_ssl_errors(vpninfo);
                destroy_esp_ciphers(esp);
        }
-       esp->seq = 0;
-       esp->seq_backlog = 0;
+
        return 0;
 }
 
-int setup_esp_keys(struct openconnect_info *vpninfo, int new_keys)
+int init_esp_ciphers(struct openconnect_info *vpninfo, struct esp *esp_out, struct esp *esp_in)
 {
-       struct esp *esp_in;
        const EVP_CIPHER *encalg;
        const EVP_MD *macalg;
        int ret;
 
-       if (vpninfo->dtls_state == DTLS_DISABLED)
-               return -EOPNOTSUPP;
-       if (!vpninfo->dtls_addr)
-               return -EINVAL;
-
        switch (vpninfo->esp_enc) {
-       case 0x02:
+       case ENC_AES_128_CBC:
                encalg = EVP_aes_128_cbc();
                break;
-       case 0x05:
+       case ENC_AES_256_CBC:
                encalg = EVP_aes_256_cbc();
                break;
        default:
@@ -132,47 +124,26 @@ int setup_esp_keys(struct openconnect_info *vpninfo, int new_keys)
        }
 
        switch (vpninfo->esp_hmac) {
-       case 0x01:
+       case HMAC_MD5:
                macalg = EVP_md5();
                break;
-       case 0x02:
+       case HMAC_SHA1:
                macalg = EVP_sha1();
                break;
        default:
                return -EINVAL;
        }
 
-       if (new_keys) {
-               vpninfo->old_esp_maxseq = vpninfo->esp_in[vpninfo->current_esp_in].seq + 32;
-               vpninfo->current_esp_in ^= 1;
-       }
-
-       esp_in = &vpninfo->esp_in[vpninfo->current_esp_in];
-
-       if (new_keys) {
-               if (!RAND_bytes((void *)&esp_in->spi, sizeof(esp_in->spi)) ||
-                   !RAND_bytes((void *)&esp_in->enc_key, vpninfo->enc_key_len) ||
-                   !RAND_bytes((void *)&esp_in->hmac_key, vpninfo->hmac_key_len) ) {
-                       vpn_progress(vpninfo, PRG_ERR,
-                                    _("Failed to generate random keys for ESP:\n"));
-                       openconnect_report_ssl_errors(vpninfo);
-                       return -EIO;
-               }
-       }
-
-       ret = init_esp_ciphers(vpninfo, &vpninfo->esp_out, macalg, encalg, 0);
+       ret = init_esp_cipher(vpninfo, &vpninfo->esp_out, macalg, encalg, 0);
        if (ret)
                return ret;
 
-       ret = init_esp_ciphers(vpninfo, esp_in, macalg, encalg, 1);
+       ret = init_esp_cipher(vpninfo, esp_in, macalg, encalg, 1);
        if (ret) {
                destroy_esp_ciphers(&vpninfo->esp_out);
                return ret;
        }
 
-       if (vpninfo->dtls_state == DTLS_NOSECRET)
-               vpninfo->dtls_state = DTLS_SECRET;
-       vpninfo->pkt_trailer = 16 + 20; /* 16 for pad, 20 for HMAC (of which we use 16) */
        return 0;
 }