From 6afaae156a9ab9de79474367d8873407f3b12a71 Mon Sep 17 00:00:00 2001 From: Neale Ranns Date: Wed, 17 Jul 2019 15:07:14 +0000 Subject: [PATCH] ipsec: GCM, Anti-replay and ESN fixess Type: fix Several Fixes: 1 - Anti-replay did not work with GCM becuase it overwrote the sequence number in the ESP header. To fix i added the seq num to the per-packet data so it is preserved 2 - The high sequence number was not byte swapped during ESP encrypt. 3 - openssl engine was the only one to return FAIL_DECRYPT for bad GCM the others return BAD_HMAC. removed the former 4 - improved tracing to show the low and high seq numbers 5 - documented the anti-replay window checks 6 - fixed scapy patch for ESN support for GCM 7 - tests for anti-reply (w/ and w/o ESN) for each crypto algo Change-Id: Id65d96b6d1d4dd821b2ab557e87468fff6d70e5b Signed-off-by: Neale Ranns --- src/plugins/crypto_openssl/main.c | 2 +- src/plugins/dpdk/ipsec/esp_decrypt.c | 6 +- src/vnet/crypto/crypto.h | 3 +- src/vnet/ipsec/ah_decrypt.c | 4 +- src/vnet/ipsec/esp_decrypt.c | 29 +++-- src/vnet/ipsec/esp_encrypt.c | 9 +- src/vnet/ipsec/ipsec_sa.h | 129 ++++++++++++++++---- test/patches/scapy-2.4/ipsec.patch | 52 ++++---- test/template_ipsec.py | 228 ++++++++++++++++++++++++++--------- test/test_ipsec_esp.py | 8 ++ 10 files changed, 345 insertions(+), 125 deletions(-) diff --git a/src/plugins/crypto_openssl/main.c b/src/plugins/crypto_openssl/main.c index fd749d04926..7362d6bd16e 100644 --- a/src/plugins/crypto_openssl/main.c +++ b/src/plugins/crypto_openssl/main.c @@ -169,7 +169,7 @@ openssl_ops_dec_gcm (vlib_main_t * vm, vnet_crypto_op_t * ops[], u32 n_ops, else { n_fail++; - op->status = VNET_CRYPTO_OP_STATUS_FAIL_DECRYPT; + op->status = VNET_CRYPTO_OP_STATUS_FAIL_BAD_HMAC; } } return n_ops - n_fail; diff --git a/src/plugins/dpdk/ipsec/esp_decrypt.c b/src/plugins/dpdk/ipsec/esp_decrypt.c index 4982db7ee6d..a82f63e6e5b 100644 --- a/src/plugins/dpdk/ipsec/esp_decrypt.c +++ b/src/plugins/dpdk/ipsec/esp_decrypt.c @@ -235,7 +235,8 @@ dpdk_esp_decrypt_inline (vlib_main_t * vm, } /* anti-replay check */ - if (ipsec_sa_anti_replay_check (sa0, &esp0->seq)) + if (ipsec_sa_anti_replay_check + (sa0, clib_host_to_net_u32 (esp0->seq))) { clib_warning ("failed anti-replay check"); if (is_ip6) @@ -549,7 +550,8 @@ dpdk_esp_decrypt_post_inline (vlib_main_t * vm, iv_size = cipher_alg->iv_len; - ipsec_sa_anti_replay_advance (sa0, esp0->seq); + ipsec_sa_anti_replay_advance (sa0, + clib_host_to_net_u32 (esp0->seq)); /* if UDP encapsulation is used adjust the address of the IP header */ if (ipsec_sa_is_set_UDP_ENCAP (sa0) diff --git a/src/vnet/crypto/crypto.h b/src/vnet/crypto/crypto.h index 9c15d53a6c1..9326a078f8a 100644 --- a/src/vnet/crypto/crypto.h +++ b/src/vnet/crypto/crypto.h @@ -65,8 +65,7 @@ typedef enum _(PENDING, "pending") \ _(COMPLETED, "completed") \ _(FAIL_NO_HANDLER, "no-handler") \ - _(FAIL_BAD_HMAC, "bad-hmac") \ - _(FAIL_DECRYPT, "decrypt-fail") + _(FAIL_BAD_HMAC, "bad-hmac") typedef enum { diff --git a/src/vnet/ipsec/ah_decrypt.c b/src/vnet/ipsec/ah_decrypt.c index 741fa91b95c..bc6b5c4ec9d 100644 --- a/src/vnet/ipsec/ah_decrypt.c +++ b/src/vnet/ipsec/ah_decrypt.c @@ -203,7 +203,7 @@ ah_decrypt_inline (vlib_main_t * vm, pd->seq = clib_host_to_net_u32 (ah0->seq_no); /* anti-replay check */ - if (ipsec_sa_anti_replay_check (sa0, &ah0->seq_no)) + if (ipsec_sa_anti_replay_check (sa0, pd->seq)) { b[0]->error = node->errors[AH_DECRYPT_ERROR_REPLAY]; next[0] = AH_DECRYPT_NEXT_DROP; @@ -303,7 +303,7 @@ ah_decrypt_inline (vlib_main_t * vm, if (PREDICT_TRUE (sa0->integ_alg != IPSEC_INTEG_ALG_NONE)) { - ipsec_sa_anti_replay_advance (sa0, clib_host_to_net_u32 (pd->seq)); + ipsec_sa_anti_replay_advance (sa0, pd->seq); } u16 ah_hdr_len = sizeof (ah_header_t) + pd->icv_size diff --git a/src/vnet/ipsec/esp_decrypt.c b/src/vnet/ipsec/esp_decrypt.c index 48f08f42e33..c2b9bf4dc0c 100644 --- a/src/vnet/ipsec/esp_decrypt.c +++ b/src/vnet/ipsec/esp_decrypt.c @@ -67,6 +67,8 @@ static char *esp_decrypt_error_strings[] = { typedef struct { u32 seq; + u32 sa_seq; + u32 sa_seq_hi; ipsec_crypto_alg_t crypto_alg; ipsec_integ_alg_t integ_alg; } esp_decrypt_trace_t; @@ -79,9 +81,11 @@ format_esp_decrypt_trace (u8 * s, va_list * args) CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *); esp_decrypt_trace_t *t = va_arg (*args, esp_decrypt_trace_t *); - s = format (s, "esp: crypto %U integrity %U seq %u", - format_ipsec_crypto_alg, t->crypto_alg, - format_ipsec_integ_alg, t->integ_alg, t->seq); + s = + format (s, + "esp: crypto %U integrity %U pkt-seq %d sa-seq %u sa-seq-hi %u", + format_ipsec_crypto_alg, t->crypto_alg, format_ipsec_integ_alg, + t->integ_alg, t->seq, t->sa_seq, t->sa_seq_hi); return s; } @@ -99,12 +103,13 @@ typedef struct u64 sa_data; }; + u32 seq; i16 current_data; i16 current_length; u16 hdr_sz; } esp_decrypt_packet_data_t; -STATIC_ASSERT_SIZEOF (esp_decrypt_packet_data_t, 2 * sizeof (u64)); +STATIC_ASSERT_SIZEOF (esp_decrypt_packet_data_t, 3 * sizeof (u64)); #define ESP_ENCRYPT_PD_F_FD_TRANSPORT (1 << 2) @@ -177,6 +182,7 @@ esp_decrypt_inline (vlib_main_t * vm, pd->current_length = b[0]->current_length; pd->hdr_sz = pd->current_data - vnet_buffer (b[0])->l3_hdr_offset; payload = b[0]->data + pd->current_data; + pd->seq = clib_host_to_net_u32 (((esp_header_t *) payload)->seq); /* we need 4 extra bytes for HMAC calculation when ESN are used */ if (ipsec_sa_is_set_USE_ESN (sa0) && pd->icv_sz && @@ -188,7 +194,7 @@ esp_decrypt_inline (vlib_main_t * vm, } /* anti-reply check */ - if (ipsec_sa_anti_replay_check (sa0, &((esp_header_t *) payload)->seq)) + if (ipsec_sa_anti_replay_check (sa0, pd->seq)) { b[0]->error = node->errors[ESP_DECRYPT_ERROR_REPLAY]; next[0] = ESP_DECRYPT_NEXT_DROP; @@ -221,10 +227,11 @@ esp_decrypt_inline (vlib_main_t * vm, op->len = len; if (ipsec_sa_is_set_USE_ESN (sa0)) { - /* shift ICV for 4 bytes to insert ESN */ + /* shift ICV by 4 bytes to insert ESN */ + u32 seq_hi = clib_host_to_net_u32 (sa0->seq_hi); u8 tmp[ESP_MAX_ICV_SIZE], sz = sizeof (sa0->seq_hi); clib_memcpy_fast (tmp, payload + len, ESP_MAX_ICV_SIZE); - clib_memcpy_fast (payload + len, &sa0->seq_hi, sz); + clib_memcpy_fast (payload + len, &seq_hi, sz); clib_memcpy_fast (payload + len + sz, tmp, ESP_MAX_ICV_SIZE); op->len += sz; op->digest += sz; @@ -368,9 +375,8 @@ esp_decrypt_inline (vlib_main_t * vm, goto trace; sa0 = vec_elt_at_index (im->sad, pd->sa_index); - u8 *payload = b[0]->data + pd->current_data; - ipsec_sa_anti_replay_advance (sa0, ((esp_header_t *) payload)->seq); + ipsec_sa_anti_replay_advance (sa0, pd->seq); esp_footer_t *f = (esp_footer_t *) (b[0]->data + pd->current_data + pd->current_length - sizeof (*f) - @@ -485,13 +491,14 @@ esp_decrypt_inline (vlib_main_t * vm, if (PREDICT_FALSE (b[0]->flags & VLIB_BUFFER_IS_TRACED)) { esp_decrypt_trace_t *tr; - u8 *payload = b[0]->data + pd->current_data; tr = vlib_add_trace (vm, node, b[0], sizeof (*tr)); sa0 = pool_elt_at_index (im->sad, vnet_buffer (b[0])->ipsec.sad_index); tr->crypto_alg = sa0->crypto_alg; tr->integ_alg = sa0->integ_alg; - tr->seq = clib_host_to_net_u32 (((esp_header_t *) payload)->seq); + tr->seq = pd->seq; + tr->sa_seq = sa0->last_seq; + tr->sa_seq_hi = sa0->seq_hi; } /* next */ diff --git a/src/vnet/ipsec/esp_encrypt.c b/src/vnet/ipsec/esp_encrypt.c index 041b268975d..47c079d95d2 100644 --- a/src/vnet/ipsec/esp_encrypt.c +++ b/src/vnet/ipsec/esp_encrypt.c @@ -65,6 +65,7 @@ typedef struct u32 sa_index; u32 spi; u32 seq; + u32 sa_seq_hi; u8 udp_encap; ipsec_crypto_alg_t crypto_alg; ipsec_integ_alg_t integ_alg; @@ -80,8 +81,9 @@ format_esp_encrypt_trace (u8 * s, va_list * args) s = format (s, - "esp: sa-index %d spi %u (0x%08x) seq %u crypto %U integrity %U%s", - t->sa_index, t->spi, t->spi, t->seq, format_ipsec_crypto_alg, + "esp: sa-index %d spi %u (0x%08x) seq %u sa-seq-hi %u crypto %U integrity %U%s", + t->sa_index, t->spi, t->spi, t->seq, t->sa_seq_hi, + format_ipsec_crypto_alg, t->crypto_alg, format_ipsec_integ_alg, t->integ_alg, t->udp_encap ? " udp-encap-enabled" : ""); return s; @@ -521,7 +523,8 @@ esp_encrypt_inline (vlib_main_t * vm, vlib_node_runtime_t * node, sizeof (*tr)); tr->sa_index = sa_index0; tr->spi = sa0->spi; - tr->seq = sa0->seq - 1; + tr->seq = sa0->seq; + tr->sa_seq_hi = sa0->seq_hi; tr->udp_encap = ipsec_sa_is_set_UDP_ENCAP (sa0); tr->crypto_alg = sa0->crypto_alg; tr->integ_alg = sa0->integ_alg; diff --git a/src/vnet/ipsec/ipsec_sa.h b/src/vnet/ipsec/ipsec_sa.h index 811f4cabcf0..86d76b3ac0a 100644 --- a/src/vnet/ipsec/ipsec_sa.h +++ b/src/vnet/ipsec/ipsec_sa.h @@ -19,8 +19,6 @@ #include #include -#define IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE (64) - #define foreach_ipsec_crypto_alg \ _ (0, NONE, "none") \ _ (1, AES_CBC_128, "aes-cbc-128") \ @@ -232,18 +230,34 @@ extern uword unformat_ipsec_integ_alg (unformat_input_t * input, va_list * args); extern uword unformat_ipsec_key (unformat_input_t * input, va_list * args); +/* + * Anti Replay definitions + */ + +#define IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE (64) +#define IPSEC_SA_ANTI_REPLAY_WINDOW_MAX_INDEX (IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE-1) + +/* + * sequence number less than the lower bound are outside of the window + * From RFC4303 Appendix A: + * Bl = Tl - W + 1 + */ +#define IPSEC_SA_ANTI_REPLAY_WINDOW_LOWER_BOUND(_tl) (_tl - IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE + 1) + +/* + * Anti replay check. + * inputs need to be in host byte order. + */ always_inline int -ipsec_sa_anti_replay_check (ipsec_sa_t * sa, u32 * seqp) +ipsec_sa_anti_replay_check (ipsec_sa_t * sa, u32 seq) { - u32 seq, diff, tl, th; + u32 diff, tl, th; + if ((sa->flags & IPSEC_SA_FLAG_USE_ANTI_REPLAY) == 0) return 0; - seq = clib_net_to_host_u32 (*seqp); - - if ((sa->flags & IPSEC_SA_FLAG_USE_ESN) == 0) + if (!ipsec_sa_is_set_USE_ESN (sa)) { - if (PREDICT_TRUE (seq > sa->last_seq)) return 0; @@ -261,50 +275,113 @@ ipsec_sa_anti_replay_check (ipsec_sa_t * sa, u32 * seqp) th = sa->last_seq_hi; diff = tl - seq; - if (PREDICT_TRUE (tl >= (IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE - 1))) + if (PREDICT_TRUE (tl >= (IPSEC_SA_ANTI_REPLAY_WINDOW_MAX_INDEX))) { - if (seq >= (tl - IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE + 1)) + /* + * the last sequence number VPP recieved is more than one + * window size greater than zero. + * Case A from RFC4303 Appendix A. + */ + if (seq < IPSEC_SA_ANTI_REPLAY_WINDOW_LOWER_BOUND (tl)) + { + /* + * the received sequence number is lower than the lower bound + * of the window, this could mean either a replay packet or that + * the high sequence number has wrapped. if it decrypts corrently + * then it's the latter. + */ + sa->seq_hi = th + 1; + return 0; + } + else { + /* + * the recieved sequence number greater than the low + * end of the window. + */ sa->seq_hi = th; if (seq <= tl) + /* + * The recieved seq number is within bounds of the window + * check if it's a duplicate + */ return (sa->replay_window & (1ULL << diff)) ? 1 : 0; else + /* + * The received sequence number is greater than the window + * upper bound. this packet will move the window along, assuming + * it decrypts correctly. + */ return 0; } - else - { - sa->seq_hi = th + 1; - return 0; - } } else { - if (seq >= (tl - IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE + 1)) + /* + * the last sequence number VPP recieved is within one window + * size of zero, i.e. 0 < TL < WINDOW_SIZE, the lower bound is thus a + * large sequence number. + * Note that the check below uses unsiged integer arthimetic, so the + * RHS will be a larger number. + * Case B from RFC4303 Appendix A. + */ + if (seq < IPSEC_SA_ANTI_REPLAY_WINDOW_LOWER_BOUND (tl)) { - sa->seq_hi = th - 1; - return (sa->replay_window & (1ULL << diff)) ? 1 : 0; + /* + * the sequence number is less than the lower bound. + */ + if (seq <= tl) + { + /* + * the packet is within the window upper bound. + * check for duplicates. + */ + sa->seq_hi = th; + return (sa->replay_window & (1ULL << diff)) ? 1 : 0; + } + else + { + /* + * the packet is less the window lower bound or greater than + * the higher bound, depending on how you look at it... + * We're assuming, given that the last sequence number received, + * TL < WINDOW_SIZE, that a largeer seq num is more likely to be + * a packet that moves the window forward, than a packet that has + * wrapped the high sequence again. If it were the latter then + * we've lost close to 2^32 packets. + */ + sa->seq_hi = th; + return 0; + } } else { - sa->seq_hi = th; - if (seq <= tl) - return (sa->replay_window & (1ULL << diff)) ? 1 : 0; - else - return 0; + /* + * the packet seq number is between the lower bound (a large nubmer) + * and MAX_SEQ_NUM. This is in the window since the window upper bound + * tl > 0. + * However, since TL is the other side of 0 to the received + * packet, the SA has moved on to a higher sequence number. + */ + sa->seq_hi = th - 1; + return (sa->replay_window & (1ULL << diff)) ? 1 : 0; } } return 0; } +/* + * Anti replay window advance + * inputs need to be in host byte order. + */ always_inline void -ipsec_sa_anti_replay_advance (ipsec_sa_t * sa, u32 seqp) +ipsec_sa_anti_replay_advance (ipsec_sa_t * sa, u32 seq) { - u32 pos, seq; + u32 pos; if (PREDICT_TRUE (sa->flags & IPSEC_SA_FLAG_USE_ANTI_REPLAY) == 0) return; - seq = clib_host_to_net_u32 (seqp); if (PREDICT_TRUE (sa->flags & IPSEC_SA_FLAG_USE_ESN)) { int wrap = sa->seq_hi - sa->last_seq_hi; diff --git a/test/patches/scapy-2.4/ipsec.patch b/test/patches/scapy-2.4/ipsec.patch index 731fe3ccc25..083b0b94961 100644 --- a/test/patches/scapy-2.4/ipsec.patch +++ b/test/patches/scapy-2.4/ipsec.patch @@ -1,30 +1,30 @@ diff --git a/scapy/layers/ipsec.py b/scapy/layers/ipsec.py -index 69e7ae3b..0c69ba1a 100644 +index 69e7ae3b..3a1724b2 100644 --- a/scapy/layers/ipsec.py +++ b/scapy/layers/ipsec.py -@@ -344,7 +344,8 @@ class CryptAlgo(object): +@@ -344,8 +344,7 @@ class CryptAlgo(object): encryptor = cipher.encryptor() if self.is_aead: - aad = struct.pack('!LL', esp.spi, esp.seq) -+ aad = struct.pack('!LQ' if sa.use_esn else '!LL', -+ esp.spi, esp.seq) - encryptor.authenticate_additional_data(aad) +- encryptor.authenticate_additional_data(aad) ++ encryptor.authenticate_additional_data(sa.build_aead(esp)) data = encryptor.update(data) + encryptor.finalize() data += encryptor.tag[:self.icv_size] -@@ -381,9 +382,9 @@ class CryptAlgo(object): + else: +@@ -380,10 +379,7 @@ class CryptAlgo(object): + if self.is_aead: # Tag value check is done during the finalize method - decryptor.authenticate_additional_data( +- decryptor.authenticate_additional_data( - struct.pack('!LL', esp.spi, esp.seq) -+ struct.pack('!LQ' if sa.use_esn else '!LL', -+ esp.spi, esp.seq) - ) +- ) - ++ decryptor.authenticate_additional_data(sa.build_aead(esp)) try: data = decryptor.update(data) + decryptor.finalize() except InvalidTag as err: -@@ -518,12 +519,16 @@ class AuthAlgo(object): +@@ -518,12 +514,16 @@ class AuthAlgo(object): else: return self.mac(key, self.digestmod(), default_backend()) @@ -42,7 +42,7 @@ index 69e7ae3b..0c69ba1a 100644 @return: the signed packet """ -@@ -534,16 +539,20 @@ class AuthAlgo(object): +@@ -534,16 +534,20 @@ class AuthAlgo(object): if pkt.haslayer(ESP): mac.update(raw(pkt[ESP])) @@ -64,7 +64,7 @@ index 69e7ae3b..0c69ba1a 100644 """ Check that the integrity check value (icv) of a packet is valid. -@@ -574,6 +583,8 @@ class AuthAlgo(object): +@@ -574,6 +578,8 @@ class AuthAlgo(object): clone = zero_mutable_fields(pkt.copy(), sending=False) mac.update(raw(clone)) @@ -73,7 +73,7 @@ index 69e7ae3b..0c69ba1a 100644 computed_icv = mac.finalize()[:self.icv_size] # XXX: Cannot use mac.verify because the ICV can be truncated -@@ -757,7 +768,8 @@ class SecurityAssociation(object): +@@ -757,7 +763,8 @@ class SecurityAssociation(object): SUPPORTED_PROTOS = (IP, IPv6) def __init__(self, proto, spi, seq_num=1, crypt_algo=None, crypt_key=None, @@ -83,7 +83,7 @@ index 69e7ae3b..0c69ba1a 100644 """ @param proto: the IPsec proto to use (ESP or AH) @param spi: the Security Parameters Index of this SA -@@ -771,6 +783,7 @@ class SecurityAssociation(object): +@@ -771,6 +778,7 @@ class SecurityAssociation(object): to encapsulate the encrypted packets. @param nat_t_header: an instance of a UDP header that will be used for NAT-Traversal. @@ -91,7 +91,7 @@ index 69e7ae3b..0c69ba1a 100644 """ if proto not in (ESP, AH, ESP.name, AH.name): -@@ -782,6 +795,7 @@ class SecurityAssociation(object): +@@ -782,6 +790,7 @@ class SecurityAssociation(object): self.spi = spi self.seq_num = seq_num @@ -99,10 +99,16 @@ index 69e7ae3b..0c69ba1a 100644 if crypt_algo: if crypt_algo not in CRYPT_ALGOS: -@@ -827,6 +841,17 @@ class SecurityAssociation(object): +@@ -827,6 +836,23 @@ class SecurityAssociation(object): raise TypeError('packet spi=0x%x does not match the SA spi=0x%x' % (pkt.spi, self.spi)) ++ def build_aead(self, esp): ++ if self.use_esn: ++ return (struct.pack('!LLL', esp.spi, self.seq_num >> 32, esp.seq)) ++ else: ++ return (struct.pack('!LL', esp.spi, esp.seq)) ++ + def build_seq_num(self, num): + # only lower order bits are transmitted + # higher order bits are used in the ICV @@ -117,7 +123,7 @@ index 69e7ae3b..0c69ba1a 100644 def _encrypt_esp(self, pkt, seq_num=None, iv=None): if iv is None: -@@ -835,7 +860,8 @@ class SecurityAssociation(object): +@@ -835,7 +861,8 @@ class SecurityAssociation(object): if len(iv) != self.crypt_algo.iv_size: raise TypeError('iv length must be %s' % self.crypt_algo.iv_size) @@ -127,7 +133,7 @@ index 69e7ae3b..0c69ba1a 100644 if self.tunnel_header: tunnel = self.tunnel_header.copy() -@@ -857,7 +883,7 @@ class SecurityAssociation(object): +@@ -857,7 +884,7 @@ class SecurityAssociation(object): esp = self.crypt_algo.pad(esp) esp = self.crypt_algo.encrypt(self, esp, self.crypt_key) @@ -136,7 +142,7 @@ index 69e7ae3b..0c69ba1a 100644 if self.nat_t_header: nat_t_header = self.nat_t_header.copy() -@@ -884,7 +910,8 @@ class SecurityAssociation(object): +@@ -884,7 +911,8 @@ class SecurityAssociation(object): def _encrypt_ah(self, pkt, seq_num=None): @@ -146,7 +152,7 @@ index 69e7ae3b..0c69ba1a 100644 icv = b"\x00" * self.auth_algo.icv_size) if self.tunnel_header: -@@ -924,7 +951,8 @@ class SecurityAssociation(object): +@@ -924,7 +952,8 @@ class SecurityAssociation(object): else: ip_header.plen = len(ip_header.payload) + len(ah) + len(payload) @@ -156,7 +162,7 @@ index 69e7ae3b..0c69ba1a 100644 # sequence number must always change, unless specified by the user if seq_num is None: -@@ -955,11 +983,12 @@ class SecurityAssociation(object): +@@ -955,11 +984,12 @@ class SecurityAssociation(object): def _decrypt_esp(self, pkt, verify=True): @@ -170,7 +176,7 @@ index 69e7ae3b..0c69ba1a 100644 esp = self.crypt_algo.decrypt(self, encrypted, self.crypt_key, self.crypt_algo.icv_size or -@@ -998,9 +1027,11 @@ class SecurityAssociation(object): +@@ -998,9 +1028,11 @@ class SecurityAssociation(object): def _decrypt_ah(self, pkt, verify=True): diff --git a/test/template_ipsec.py b/test/template_ipsec.py index e40fa561dbd..25cff7f2edf 100644 --- a/test/template_ipsec.py +++ b/test/template_ipsec.py @@ -84,14 +84,18 @@ class IPsecIPv6Params(object): self.nat_header = None +def mk_scapy_crpyt_key(p): + if p.crypt_algo == "AES-GCM": + return p.crypt_key + struct.pack("!I", p.salt) + else: + return p.crypt_key + + def config_tun_params(p, encryption_type, tun_if): ip_class_by_addr_type = {socket.AF_INET: IP, socket.AF_INET6: IPv6} use_esn = bool(p.flags & (VppEnum.vl_api_ipsec_sad_flags_t. IPSEC_API_SAD_FLAG_USE_ESN)) - if p.crypt_algo == "AES-GCM": - crypt_key = p.crypt_key + struct.pack("!I", p.salt) - else: - crypt_key = p.crypt_key + crypt_key = mk_scapy_crpyt_key(p) p.scapy_tun_sa = SecurityAssociation( encryption_type, spi=p.vpp_tun_spi, crypt_algo=p.crypt_algo, @@ -117,10 +121,7 @@ def config_tun_params(p, encryption_type, tun_if): def config_tra_params(p, encryption_type): use_esn = bool(p.flags & (VppEnum.vl_api_ipsec_sad_flags_t. IPSEC_API_SAD_FLAG_USE_ESN)) - if p.crypt_algo == "AES-GCM": - crypt_key = p.crypt_key + struct.pack("!I", p.salt) - else: - crypt_key = p.crypt_key + crypt_key = mk_scapy_crpyt_key(p) p.scapy_tra_sa = SecurityAssociation( encryption_type, spi=p.vpp_tra_spi, @@ -269,32 +270,68 @@ class IpsecTcpTests(IpsecTcp): class IpsecTra4(object): """ verify methods for Transport v4 """ - def verify_tra_anti_replay(self, count=1): + def verify_tra_anti_replay(self): p = self.params[socket.AF_INET] use_esn = p.vpp_tra_sa.use_esn - # fire in a packet with seq number 1 - pkt = (Ether(src=self.tra_if.remote_mac, - dst=self.tra_if.local_mac) / - p.scapy_tra_sa.encrypt(IP(src=self.tra_if.remote_ip4, - dst=self.tra_if.local_ip4) / - ICMP(), - seq_num=1)) - recv_pkts = self.send_and_expect(self.tra_if, [pkt], self.tra_if) + seq_cycle_node_name = ('/err/%s/sequence number cycled' % + self.tra4_encrypt_node_name) + replay_node_name = ('/err/%s/SA replayed packet' % + self.tra4_decrypt_node_name) + if ESP == self.encryption_type and p.crypt_algo == "AES-GCM": + hash_failed_node_name = ('/err/%s/ESP decryption failed' % + self.tra4_decrypt_node_name) + else: + hash_failed_node_name = ('/err/%s/Integrity check failed' % + self.tra4_decrypt_node_name) + replay_count = self.statistics.get_err_counter(replay_node_name) + hash_failed_count = self.statistics.get_err_counter( + hash_failed_node_name) + seq_cycle_count = self.statistics.get_err_counter(seq_cycle_node_name) + + if ESP == self.encryption_type: + undersize_node_name = ('/err/%s/undersized packet' % + self.tra4_decrypt_node_name) + undersize_count = self.statistics.get_err_counter( + undersize_node_name) + + # + # send packets with seq numbers 1->34 + # this means the window size is still in Case B (see RFC4303 + # Appendix A) + # + # for reasons i haven't investigated Scapy won't create a packet with + # seq_num=0 + # + pkts = [(Ether(src=self.tra_if.remote_mac, + dst=self.tra_if.local_mac) / + p.scapy_tra_sa.encrypt(IP(src=self.tra_if.remote_ip4, + dst=self.tra_if.local_ip4) / + ICMP(), + seq_num=seq)) + for seq in range(1, 34)] + recv_pkts = self.send_and_expect(self.tra_if, pkts, self.tra_if) - # now move the window over to 235 + # replayed packets are dropped + self.send_and_assert_no_replies(self.tra_if, pkts) + replay_count += len(pkts) + self.assert_error_counter_equal(replay_node_name, replay_count) + + # + # now move the window over to 257 (more than one byte) and into Case A + # pkt = (Ether(src=self.tra_if.remote_mac, dst=self.tra_if.local_mac) / p.scapy_tra_sa.encrypt(IP(src=self.tra_if.remote_ip4, dst=self.tra_if.local_ip4) / ICMP(), - seq_num=235)) + seq_num=257)) recv_pkts = self.send_and_expect(self.tra_if, [pkt], self.tra_if) # replayed packets are dropped self.send_and_assert_no_replies(self.tra_if, pkt * 3) - self.assert_error_counter_equal( - '/err/%s/SA replayed packet' % self.tra4_decrypt_node_name, 3) + replay_count += 3 + self.assert_error_counter_equal(replay_node_name, replay_count) # the window size is 64 packets # in window are still accepted @@ -303,14 +340,14 @@ class IpsecTra4(object): p.scapy_tra_sa.encrypt(IP(src=self.tra_if.remote_ip4, dst=self.tra_if.local_ip4) / ICMP(), - seq_num=172)) + seq_num=200)) recv_pkts = self.send_and_expect(self.tra_if, [pkt], self.tra_if) # a packet that does not decrypt does not move the window forward bogus_sa = SecurityAssociation(self.encryption_type, p.vpp_tra_spi, crypt_algo=p.crypt_algo, - crypt_key=p.crypt_key[::-1], + crypt_key=mk_scapy_crpyt_key(p)[::-1], auth_algo=p.auth_algo, auth_key=p.auth_key[::-1]) pkt = (Ether(src=self.tra_if.remote_mac, @@ -321,8 +358,9 @@ class IpsecTra4(object): seq_num=350)) self.send_and_assert_no_replies(self.tra_if, pkt * 17) - self.assert_error_counter_equal( - '/err/%s/Integrity check failed' % self.tra4_decrypt_node_name, 17) + hash_failed_count += 17 + self.assert_error_counter_equal(hash_failed_node_name, + hash_failed_count) # a malformed 'runt' packet # created by a mis-constructed SA @@ -337,8 +375,9 @@ class IpsecTra4(object): seq_num=350)) self.send_and_assert_no_replies(self.tra_if, pkt * 17) - self.assert_error_counter_equal( - '/err/%s/undersized packet' % self.tra4_decrypt_node_name, 17) + undersize_count += 17 + self.assert_error_counter_equal(undersize_node_name, + undersize_count) # which we can determine since this packet is still in the window pkt = (Ether(src=self.tra_if.remote_mac, @@ -349,7 +388,11 @@ class IpsecTra4(object): seq_num=234)) self.send_and_expect(self.tra_if, [pkt], self.tra_if) + # # out of window are dropped + # this is Case B. So VPP will consider this to be a high seq num wrap + # and so the decrypt attempt will fail + # pkt = (Ether(src=self.tra_if.remote_mac, dst=self.tra_if.local_mac) / p.scapy_tra_sa.encrypt(IP(src=self.tra_if.remote_ip4, @@ -361,44 +404,59 @@ class IpsecTra4(object): if use_esn: # an out of window error with ESN looks like a high sequence # wrap. but since it isn't then the verify will fail. - self.assert_error_counter_equal( - '/err/%s/Integrity check failed' % - self.tra4_decrypt_node_name, 34) + hash_failed_count += 17 + self.assert_error_counter_equal(hash_failed_node_name, + hash_failed_count) else: - self.assert_error_counter_equal( - '/err/%s/SA replayed packet' % - self.tra4_decrypt_node_name, 20) + replay_count += 17 + self.assert_error_counter_equal(replay_node_name, + replay_count) - # valid packet moves the window over to 236 + # valid packet moves the window over to 258 pkt = (Ether(src=self.tra_if.remote_mac, dst=self.tra_if.local_mac) / p.scapy_tra_sa.encrypt(IP(src=self.tra_if.remote_ip4, dst=self.tra_if.local_ip4) / ICMP(), - seq_num=236)) + seq_num=258)) rx = self.send_and_expect(self.tra_if, [pkt], self.tra_if) decrypted = p.vpp_tra_sa.decrypt(rx[0][IP]) - # move VPP's SA to just before the seq-number wrap + # + # move VPP's SA TX seq-num to just before the seq-number wrap. + # then fire in a packet that VPP should drop on TX because it + # causes the TX seq number to wrap; unless we're using extened sequence + # numbers. + # self.vapi.cli("test ipsec sa %d seq 0xffffffff" % p.scapy_tra_sa_id) + self.logger.info(self.vapi.ppcli("show ipsec sa 0")) + self.logger.info(self.vapi.ppcli("show ipsec sa 1")) - # then fire in a packet that VPP should drop because it causes the - # seq number to wrap unless we're using extended. - pkt = (Ether(src=self.tra_if.remote_mac, - dst=self.tra_if.local_mac) / - p.scapy_tra_sa.encrypt(IP(src=self.tra_if.remote_ip4, - dst=self.tra_if.local_ip4) / - ICMP(), - seq_num=237)) + pkts = [(Ether(src=self.tra_if.remote_mac, + dst=self.tra_if.local_mac) / + p.scapy_tra_sa.encrypt(IP(src=self.tra_if.remote_ip4, + dst=self.tra_if.local_ip4) / + ICMP(), + seq_num=seq)) + for seq in range(259, 280)] if use_esn: - rx = self.send_and_expect(self.tra_if, [pkt], self.tra_if) - # in order to decrpyt the high order number needs to wrap - p.vpp_tra_sa.seq_num = 0x100000000 - decrypted = p.vpp_tra_sa.decrypt(rx[0][IP]) + rxs = self.send_and_expect(self.tra_if, pkts, self.tra_if) - # send packets with high bits set + # + # in order for scapy to decrypt its SA's high order number needs + # to wrap + # + p.vpp_tra_sa.seq_num = 0x100000000 + for rx in rxs: + decrypted = p.vpp_tra_sa.decrypt(rx[0][IP]) + + # + # wrap scapy's TX high sequence number. VPP is in case B, so it + # will consider this a high seq wrap also. + # The low seq num we set it to will place VPP's RX window in Case A + # p.scapy_tra_sa.seq_num = 0x100000005 pkt = (Ether(src=self.tra_if.remote_mac, dst=self.tra_if.local_mac) / @@ -407,13 +465,72 @@ class IpsecTra4(object): ICMP(), seq_num=0x100000005)) rx = self.send_and_expect(self.tra_if, [pkt], self.tra_if) - # in order to decrpyt the high order number needs to wrap decrypted = p.vpp_tra_sa.decrypt(rx[0][IP]) + + # + # A packet that has seq num between (2^32-64) and 5 is within + # the window + # + p.scapy_tra_sa.seq_num = 0xfffffffd + pkt = (Ether(src=self.tra_if.remote_mac, + dst=self.tra_if.local_mac) / + p.scapy_tra_sa.encrypt(IP(src=self.tra_if.remote_ip4, + dst=self.tra_if.local_ip4) / + ICMP(), + seq_num=0xfffffffd)) + rx = self.send_and_expect(self.tra_if, [pkt], self.tra_if) + decrypted = p.vpp_tra_sa.decrypt(rx[0][IP]) + + # + # While in case A we cannot wrap the high sequence number again + # becuase VPP will consider this packet to be one that moves the + # window forward + # + pkt = (Ether(src=self.tra_if.remote_mac, + dst=self.tra_if.local_mac) / + p.scapy_tra_sa.encrypt(IP(src=self.tra_if.remote_ip4, + dst=self.tra_if.local_ip4) / + ICMP(), + seq_num=0x200000999)) + self.send_and_assert_no_replies(self.tra_if, [pkt], self.tra_if) + + hash_failed_count += 1 + self.assert_error_counter_equal(hash_failed_node_name, + hash_failed_count) + + # + # but if we move the wondow forward to case B, then we can wrap + # again + # + p.scapy_tra_sa.seq_num = 0x100000555 + pkt = (Ether(src=self.tra_if.remote_mac, + dst=self.tra_if.local_mac) / + p.scapy_tra_sa.encrypt(IP(src=self.tra_if.remote_ip4, + dst=self.tra_if.local_ip4) / + ICMP(), + seq_num=0x100000555)) + rx = self.send_and_expect(self.tra_if, [pkt], self.tra_if) + decrypted = p.vpp_tra_sa.decrypt(rx[0][IP]) + + p.scapy_tra_sa.seq_num = 0x200000444 + pkt = (Ether(src=self.tra_if.remote_mac, + dst=self.tra_if.local_mac) / + p.scapy_tra_sa.encrypt(IP(src=self.tra_if.remote_ip4, + dst=self.tra_if.local_ip4) / + ICMP(), + seq_num=0x200000444)) + rx = self.send_and_expect(self.tra_if, [pkt], self.tra_if) + decrypted = p.vpp_tra_sa.decrypt(rx[0][IP]) + else: - self.send_and_assert_no_replies(self.tra_if, [pkt]) - self.assert_error_counter_equal( - '/err/%s/sequence number cycled' % - self.tra4_encrypt_node_name, 1) + # + # without ESN TX sequence numbers can't wrap and packets are + # dropped from here on out. + # + self.send_and_assert_no_replies(self.tra_if, pkts) + seq_cycle_count += len(pkts) + self.assert_error_counter_equal(seq_cycle_node_name, + seq_cycle_count) # move the security-associations seq number on to the last we used self.vapi.cli("test ipsec sa %d seq 0x15f" % p.scapy_tra_sa_id) @@ -423,6 +540,7 @@ class IpsecTra4(object): def verify_tra_basic4(self, count=1): """ ipsec v4 transport basic test """ self.vapi.cli("clear errors") + self.vapi.cli("clear ipsec sa") try: p = self.params[socket.AF_INET] send_pkts = self.gen_encrypt_pkts(p.scapy_tra_sa, self.tra_if, @@ -461,7 +579,7 @@ class IpsecTra4Tests(IpsecTra4): """ UT test methods for Transport v4 """ def test_tra_anti_replay(self): """ ipsec v4 transport anti-reply test """ - self.verify_tra_anti_replay(count=1) + self.verify_tra_anti_replay() def test_tra_basic(self, count=1): """ ipsec v4 transport basic test """ diff --git a/test/test_ipsec_esp.py b/test/test_ipsec_esp.py index 4da88911016..f5bbc54bd62 100644 --- a/test/test_ipsec_esp.py +++ b/test/test_ipsec_esp.py @@ -486,6 +486,14 @@ class TestIpsecEspAll(ConfigIpsecESP, # self.unconfig_network() + # + # reconfigure the network and SA to run the + # anti replay tests + # + self.config_network(self.params.values()) + self.verify_tra_anti_replay() + self.unconfig_network() + if __name__ == '__main__': unittest.main(testRunner=VppTestRunner) -- 2.16.6