#define _IP_VHL
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/domain.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/errno.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <sys/syslog.h>
#include <net/if.h>
#include <net/route.h>
#include <net/multi_layer_pkt_log.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/in_var.h>
#include <netinet/udp.h>
#include <netinet/tcp.h>
#include <netinet/in_tclass.h>
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet/icmp6.h>
#include <netinet6/ipsec.h>
#include <netinet6/ipsec6.h>
#include <netinet6/ah.h>
#include <netinet6/ah6.h>
#include <netinet6/esp.h>
#include <netinet6/esp6.h>
#include <netkey/key.h>
#include <netkey/keydb.h>
#include <net/net_osdep.h>
#include <sys/kdebug.h>
#define DBG_LAYER_BEG NETDBG_CODE(DBG_NETIPSEC, 1)
#define DBG_LAYER_END NETDBG_CODE(DBG_NETIPSEC, 3)
#define DBG_FNC_ESPOUT NETDBG_CODE(DBG_NETIPSEC, (4 << 8))
#define DBG_FNC_ENCRYPT NETDBG_CODE(DBG_NETIPSEC, (5 << 8))
static int esp_output(struct mbuf *, u_char *, struct mbuf *,
int, struct secasvar *sav);
extern int esp_udp_encap_port;
extern u_int64_t natt_now;
extern lck_mtx_t *sadb_mutex;
size_t
esp_hdrsiz(__unused struct ipsecrequest *isr)
{
#if 0
if (isr == NULL) {
panic("esp_hdrsiz: NULL was passed.\n");
}
lck_mtx_lock(sadb_mutex);
{
struct secasvar *sav;
const struct esp_algorithm *algo;
const struct ah_algorithm *aalgo;
size_t ivlen;
size_t authlen;
size_t hdrsiz;
size_t maxpad;
sav = isr->sav;
if (isr->saidx.proto != IPPROTO_ESP) {
panic("unsupported mode passed to esp_hdrsiz");
}
if (sav == NULL) {
goto estimate;
}
if (sav->state != SADB_SASTATE_MATURE
&& sav->state != SADB_SASTATE_DYING) {
goto estimate;
}
algo = esp_algorithm_lookup(sav->alg_enc);
if (!algo) {
goto estimate;
}
ivlen = sav->ivlen;
if (ivlen < 0) {
goto estimate;
}
if (algo->padbound) {
maxpad = algo->padbound;
} else {
maxpad = 4;
}
maxpad += 1;
if (sav->flags & SADB_X_EXT_OLD) {
hdrsiz = sizeof(struct esp) + ivlen + maxpad;
} else {
aalgo = ah_algorithm_lookup(sav->alg_auth);
if (aalgo && sav->replay[0] != NULL && sav->key_auth) {
authlen = (aalgo->sumsiz)(sav);
} else {
authlen = 0;
}
hdrsiz = sizeof(struct newesp) + ivlen + maxpad + authlen;
}
if ((sav->flags & SADB_X_EXT_NATT) != 0) {
hdrsiz += sizeof(struct udphdr) + 4;
}
lck_mtx_unlock(sadb_mutex);
return hdrsiz;
}
estimate:
lck_mtx_unlock(sadb_mutex);
#endif
return sizeof(struct newesp) + esp_max_ivlen() + 17 + AH_MAXSUMSIZE + sizeof(struct udphdr);
}
static int
esp_output(
struct mbuf *m,
u_char *nexthdrp,
struct mbuf *md,
int af,
struct secasvar *sav)
{
struct mbuf *n;
struct mbuf *mprev;
struct esp *esp;
struct esptail *esptail;
const struct esp_algorithm *algo;
struct tcphdr th = {};
u_int32_t spi;
u_int32_t seq;
size_t inner_payload_len = 0;
u_int8_t inner_protocol = 0;
u_int8_t nxt = 0;
size_t plen;
size_t espoff;
size_t esphlen;
int ivlen;
int afnumber;
size_t extendsiz;
int error = 0;
struct ipsecstat *stat;
struct udphdr *udp = NULL;
int udp_encapsulate = (sav->flags & SADB_X_EXT_NATT && (af == AF_INET || af == AF_INET6) &&
((esp_udp_encap_port & 0xFFFF) != 0 || sav->natt_encapsulated_src_port != 0));
KERNEL_DEBUG(DBG_FNC_ESPOUT | DBG_FUNC_START, sav->ivlen, 0, 0, 0, 0);
switch (af) {
case AF_INET:
afnumber = 4;
stat = &ipsecstat;
break;
case AF_INET6:
afnumber = 6;
stat = &ipsec6stat;
break;
default:
ipseclog((LOG_ERR, "esp_output: unsupported af %d\n", af));
KERNEL_DEBUG(DBG_FNC_ESPOUT | DBG_FUNC_END, 1, 0, 0, 0, 0);
return 0;
}
mbuf_traffic_class_t traffic_class = 0;
if ((sav->flags2 & SADB_X_EXT_SA2_SEQ_PER_TRAFFIC_CLASS) ==
SADB_X_EXT_SA2_SEQ_PER_TRAFFIC_CLASS) {
u_int8_t dscp = 0;
switch (af) {
case AF_INET:
{
struct ip *ip = mtod(m, struct ip *);
dscp = ip->ip_tos >> IPTOS_DSCP_SHIFT;
break;
}
case AF_INET6:
{
struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
dscp = (ntohl(ip6->ip6_flow) & IP6FLOW_DSCP_MASK) >> IP6FLOW_DSCP_SHIFT;
break;
}
default:
panic("esp_output: should not reach here");
}
traffic_class = rfc4594_dscp_to_tc(dscp);
}
if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay[traffic_class] == NULL) {
switch (af) {
case AF_INET:
{
struct ip *ip;
ip = mtod(m, struct ip *);
ipseclog((LOG_DEBUG, "esp4_output: internal error: "
"sav->replay is null: %x->%x, SPI=%u\n",
(u_int32_t)ntohl(ip->ip_src.s_addr),
(u_int32_t)ntohl(ip->ip_dst.s_addr),
(u_int32_t)ntohl(sav->spi)));
IPSEC_STAT_INCREMENT(ipsecstat.out_inval);
break;
}
case AF_INET6:
ipseclog((LOG_DEBUG, "esp6_output: internal error: "
"sav->replay is null: SPI=%u\n",
(u_int32_t)ntohl(sav->spi)));
IPSEC_STAT_INCREMENT(ipsec6stat.out_inval);
break;
default:
panic("esp_output: should not reach here");
}
m_freem(m);
KERNEL_DEBUG(DBG_FNC_ESPOUT | DBG_FUNC_END, 2, 0, 0, 0, 0);
return EINVAL;
}
algo = esp_algorithm_lookup(sav->alg_enc);
if (!algo) {
ipseclog((LOG_ERR, "esp_output: unsupported algorithm: "
"SPI=%u\n", (u_int32_t)ntohl(sav->spi)));
m_freem(m);
KERNEL_DEBUG(DBG_FNC_ESPOUT | DBG_FUNC_END, 3, 0, 0, 0, 0);
return EINVAL;
}
spi = sav->spi;
ivlen = sav->ivlen;
if (ivlen < 0) {
panic("invalid ivlen");
}
{
struct ip *ip = NULL;
struct ip6_hdr *ip6 = NULL;
size_t esplen;
size_t hlen = 0;
if (sav->flags & SADB_X_EXT_OLD) {
esplen = sizeof(struct esp);
} else {
if (sav->flags & SADB_X_EXT_DERIV) {
esplen = sizeof(struct esp);
} else {
esplen = sizeof(struct newesp);
}
}
esphlen = esplen + ivlen;
for (mprev = m; mprev && mprev->m_next != md; mprev = mprev->m_next) {
;
}
if (mprev == NULL || mprev->m_next != md) {
ipseclog((LOG_DEBUG, "esp%d_output: md is not in chain\n",
afnumber));
m_freem(m);
KERNEL_DEBUG(DBG_FNC_ESPOUT | DBG_FUNC_END, 4, 0, 0, 0, 0);
return EINVAL;
}
plen = 0;
for (n = md; n; n = n->m_next) {
plen += n->m_len;
}
switch (af) {
case AF_INET:
ip = mtod(m, struct ip *);
#ifdef _IP_VHL
hlen = IP_VHL_HL(ip->ip_vhl) << 2;
#else
hlen = ip->ip_hl << 2;
#endif
break;
case AF_INET6:
ip6 = mtod(m, struct ip6_hdr *);
hlen = sizeof(*ip6);
break;
}
struct secashead *sah = sav->sah;
if (net_mpklog_enabled &&
sah != NULL && sah->ipsec_if != NULL) {
ifnet_t ifp = sah->ipsec_if;
if ((ifp->if_xflags & IFXF_MPK_LOG) == IFXF_MPK_LOG) {
size_t iphlen = 0;
if (sav->sah->saidx.mode == IPSEC_MODE_TUNNEL) {
struct ip *inner_ip = mtod(md, struct ip *);
if (IP_VHL_V(inner_ip->ip_vhl) == IPVERSION) {
#ifdef _IP_VHL
iphlen = IP_VHL_HL(inner_ip->ip_vhl) << 2;
#else
iphlen = inner_ip->ip_hl << 2;
#endif
inner_protocol = inner_ip->ip_p;
} else if (IP_VHL_V(inner_ip->ip_vhl) == IPV6_VERSION) {
struct ip6_hdr *inner_ip6 = mtod(md, struct ip6_hdr *);
iphlen = sizeof(struct ip6_hdr);
inner_protocol = inner_ip6->ip6_nxt;
}
if (inner_protocol == IPPROTO_TCP) {
if ((int)(iphlen + sizeof(th)) <=
(m->m_pkthdr.len - m->m_len)) {
m_copydata(md, (int)iphlen, sizeof(th), (u_int8_t *)&th);
}
inner_payload_len = m->m_pkthdr.len - m->m_len - iphlen - (th.th_off << 2);
}
} else {
iphlen = hlen;
if (af == AF_INET) {
inner_protocol = ip->ip_p;
} else if (af == AF_INET6) {
inner_protocol = ip6->ip6_nxt;
}
if (inner_protocol == IPPROTO_TCP) {
if ((int)(iphlen + sizeof(th)) <=
m->m_pkthdr.len) {
m_copydata(m, (int)iphlen, sizeof(th), (u_int8_t *)&th);
}
inner_payload_len = m->m_pkthdr.len - iphlen - (th.th_off << 2);
}
}
}
}
mprev->m_next = NULL;
if ((md = ipsec_copypkt(md)) == NULL) {
m_freem(m);
error = ENOBUFS;
goto fail;
}
mprev->m_next = md;
if ((sav->flags & SADB_X_EXT_NATT_MULTIPLEUSERS) != 0) {
if (ip->ip_p != IPPROTO_UDP) {
IPSEC_STAT_INCREMENT(ipsecstat.out_inval);
m_freem(m);
error = EINVAL;
goto fail;
}
udp = mtod(md, struct udphdr *);
if (sav->natt_encapsulated_src_port == 0) {
if (key_natt_get_translated_port(sav) == 0) {
m_freem(m);
error = EINVAL;
goto fail;
}
}
if (sav->remote_ike_port == htons(udp->uh_dport)) {
udp->uh_dport = sav->natt_encapsulated_src_port;
udp->uh_sum = 0;
} else {
IPSEC_STAT_INCREMENT(ipsecstat.out_inval);
m_freem(m);
error = EINVAL;
goto fail;
}
}
espoff = m->m_pkthdr.len - plen;
if (udp_encapsulate) {
esphlen += sizeof(struct udphdr);
espoff += sizeof(struct udphdr);
}
if (M_LEADINGSPACE(md) < esphlen || (md->m_flags & M_EXT) != 0) {
MGET(n, M_DONTWAIT, MT_DATA);
if (!n) {
m_freem(m);
error = ENOBUFS;
goto fail;
}
VERIFY(esphlen <= INT32_MAX);
n->m_len = (int)esphlen;
mprev->m_next = n;
n->m_next = md;
m->m_pkthdr.len += esphlen;
if (udp_encapsulate) {
udp = mtod(n, struct udphdr *);
esp = (struct esp *)(void *)((caddr_t)udp + sizeof(struct udphdr));
} else {
esp = mtod(n, struct esp *);
}
} else {
md->m_len += esphlen;
md->m_data -= esphlen;
m->m_pkthdr.len += esphlen;
esp = mtod(md, struct esp *);
if (udp_encapsulate) {
udp = mtod(md, struct udphdr *);
esp = (struct esp *)(void *)((caddr_t)udp + sizeof(struct udphdr));
} else {
esp = mtod(md, struct esp *);
}
}
switch (af) {
case AF_INET:
if (esphlen < (IP_MAXPACKET - ntohs(ip->ip_len))) {
ip->ip_len = htons(ntohs(ip->ip_len) + (u_short)esphlen);
} else {
ipseclog((LOG_ERR,
"IPv4 ESP output: size exceeds limit\n"));
IPSEC_STAT_INCREMENT(ipsecstat.out_inval);
m_freem(m);
error = EMSGSIZE;
goto fail;
}
break;
case AF_INET6:
break;
}
}
esp->esp_spi = spi;
if ((sav->flags & SADB_X_EXT_OLD) == 0) {
struct newesp *nesp;
nesp = (struct newesp *)esp;
if (sav->replay[traffic_class]->count == sav->replay[traffic_class]->lastseq) {
if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) {
ipseclog((LOG_WARNING,
"replay counter overflowed. %s\n",
ipsec_logsastr(sav)));
IPSEC_STAT_INCREMENT(stat->out_inval);
m_freem(m);
KERNEL_DEBUG(DBG_FNC_ESPOUT | DBG_FUNC_END, 5, 0, 0, 0, 0);
return EINVAL;
}
}
lck_mtx_lock(sadb_mutex);
sav->replay[traffic_class]->count++;
lck_mtx_unlock(sadb_mutex);
nesp->esp_seq = htonl(sav->replay[traffic_class]->count);
seq = sav->replay[traffic_class]->count;
}
{
struct ip *ip = NULL;
size_t padbound;
u_char *extend;
int i;
int randpadmax;
if (algo->padbound) {
padbound = algo->padbound;
} else {
padbound = 4;
}
if (padbound < 4) {
padbound = 4;
}
extendsiz = padbound - (plen % padbound);
if (extendsiz == 1) {
extendsiz = padbound + 1;
}
switch (af) {
case AF_INET:
randpadmax = ip4_esp_randpad;
break;
case AF_INET6:
randpadmax = ip6_esp_randpad;
break;
default:
randpadmax = -1;
break;
}
if (randpadmax < 0 || plen + extendsiz >= randpadmax) {
;
} else {
size_t pad;
randpadmax = (int)((randpadmax / padbound) * padbound);
pad = (randpadmax - plen + extendsiz) / padbound;
if (pad > 0) {
pad = (random() % pad) * padbound;
} else {
pad = 0;
}
if (extendsiz + pad <= MLEN && extendsiz + pad < 256) {
extendsiz += pad;
}
}
n = m;
while (n->m_next) {
n = n->m_next;
}
if (!(n->m_flags & M_EXT) && extendsiz < M_TRAILINGSPACE(n)) {
extend = mtod(n, u_char *) + n->m_len;
n->m_len += (int)extendsiz;
m->m_pkthdr.len += extendsiz;
} else {
struct mbuf *nn;
MGET(nn, M_DONTWAIT, MT_DATA);
if (!nn) {
ipseclog((LOG_DEBUG, "esp%d_output: can't alloc mbuf",
afnumber));
m_freem(m);
error = ENOBUFS;
goto fail;
}
extend = mtod(nn, u_char *);
VERIFY(extendsiz <= INT_MAX);
nn->m_len = (int)extendsiz;
nn->m_next = NULL;
n->m_next = nn;
n = nn;
m->m_pkthdr.len += extendsiz;
}
switch (sav->flags & SADB_X_EXT_PMASK) {
case SADB_X_EXT_PRAND:
key_randomfill(extend, extendsiz);
break;
case SADB_X_EXT_PZERO:
bzero(extend, extendsiz);
break;
case SADB_X_EXT_PSEQ:
for (i = 0; i < extendsiz; i++) {
extend[i] = (i + 1) & 0xff;
}
break;
}
nxt = *nexthdrp;
if (udp_encapsulate) {
*nexthdrp = IPPROTO_UDP;
if (sav->natt_encapsulated_src_port != 0) {
udp->uh_sport = (u_short)sav->natt_encapsulated_src_port;
} else {
udp->uh_sport = htons((u_short)esp_udp_encap_port);
}
udp->uh_dport = htons(sav->remote_ike_port);
udp->uh_sum = 0;
sav->natt_last_activity = natt_now;
} else {
*nexthdrp = IPPROTO_ESP;
}
esptail = (struct esptail *)
(mtod(n, u_int8_t *) + n->m_len - sizeof(struct esptail));
esptail->esp_nxt = nxt;
VERIFY((extendsiz - 2) <= UINT8_MAX);
esptail->esp_padlen = (u_int8_t)(extendsiz - 2);
switch (af) {
case AF_INET:
ip = mtod(m, struct ip *);
if (extendsiz < (IP_MAXPACKET - ntohs(ip->ip_len))) {
ip->ip_len = htons(ntohs(ip->ip_len) + (u_short)extendsiz);
} else {
ipseclog((LOG_ERR,
"IPv4 ESP output: size exceeds limit\n"));
IPSEC_STAT_INCREMENT(ipsecstat.out_inval);
m_freem(m);
error = EMSGSIZE;
goto fail;
}
break;
case AF_INET6:
break;
}
}
error = esp_schedule(algo, sav);
if (error) {
m_freem(m);
IPSEC_STAT_INCREMENT(stat->out_inval);
goto fail;
}
if (!algo->encrypt) {
panic("internal error: no encrypt function");
}
KERNEL_DEBUG(DBG_FNC_ENCRYPT | DBG_FUNC_START, 0, 0, 0, 0, 0);
if ((*algo->encrypt)(m, espoff, plen + extendsiz, sav, algo, ivlen)) {
ipseclog((LOG_ERR, "packet encryption failure\n"));
IPSEC_STAT_INCREMENT(stat->out_inval);
error = EINVAL;
KERNEL_DEBUG(DBG_FNC_ENCRYPT | DBG_FUNC_END, 1, error, 0, 0, 0);
goto fail;
}
KERNEL_DEBUG(DBG_FNC_ENCRYPT | DBG_FUNC_END, 2, 0, 0, 0, 0);
size_t siz = 0;
u_char authbuf[AH_MAXSUMSIZE] __attribute__((aligned(4)));
if (algo->finalizeencrypt) {
siz = algo->icvlen;
if ((*algo->finalizeencrypt)(sav, authbuf, siz)) {
ipseclog((LOG_ERR, "packet encryption ICV failure\n"));
IPSEC_STAT_INCREMENT(stat->out_inval);
error = EINVAL;
KERNEL_DEBUG(DBG_FNC_ENCRYPT | DBG_FUNC_END, 1, error, 0, 0, 0);
goto fail;
}
goto fill_icv;
}
if (!sav->replay[traffic_class]) {
goto noantireplay;
}
if (!sav->key_auth) {
goto noantireplay;
}
if (sav->key_auth == SADB_AALG_NONE) {
goto noantireplay;
}
{
const struct ah_algorithm *aalgo;
aalgo = ah_algorithm_lookup(sav->alg_auth);
if (!aalgo) {
goto noantireplay;
}
siz = ((aalgo->sumsiz)(sav) + 3) & ~(4 - 1);
if (AH_MAXSUMSIZE < siz) {
panic("assertion failed for AH_MAXSUMSIZE");
}
if (esp_auth(m, espoff, m->m_pkthdr.len - espoff, sav, authbuf)) {
ipseclog((LOG_ERR, "ESP checksum generation failure\n"));
m_freem(m);
error = EINVAL;
IPSEC_STAT_INCREMENT(stat->out_inval);
goto fail;
}
}
fill_icv:
{
struct ip *ip;
u_char *p;
n = m;
while (n->m_next) {
n = n->m_next;
}
if (!(n->m_flags & M_EXT) && siz < M_TRAILINGSPACE(n)) {
n->m_len += siz;
m->m_pkthdr.len += siz;
p = mtod(n, u_char *) + n->m_len - siz;
} else {
struct mbuf *nn;
MGET(nn, M_DONTWAIT, MT_DATA);
if (!nn) {
ipseclog((LOG_DEBUG, "can't alloc mbuf in esp%d_output",
afnumber));
m_freem(m);
error = ENOBUFS;
goto fail;
}
nn->m_len = (int)siz;
nn->m_next = NULL;
n->m_next = nn;
n = nn;
m->m_pkthdr.len += siz;
p = mtod(nn, u_char *);
}
bcopy(authbuf, p, siz);
switch (af) {
case AF_INET:
ip = mtod(m, struct ip *);
if (siz < (IP_MAXPACKET - ntohs(ip->ip_len))) {
ip->ip_len = htons(ntohs(ip->ip_len) + (u_short)siz);
} else {
ipseclog((LOG_ERR,
"IPv4 ESP output: size exceeds limit\n"));
IPSEC_STAT_INCREMENT(ipsecstat.out_inval);
m_freem(m);
error = EMSGSIZE;
goto fail;
}
break;
case AF_INET6:
break;
}
}
if (udp_encapsulate) {
struct ip *ip;
struct ip6_hdr *ip6;
switch (af) {
case AF_INET:
ip = mtod(m, struct ip *);
udp->uh_ulen = htons((u_int16_t)(ntohs(ip->ip_len) - (IP_VHL_HL(ip->ip_vhl) << 2)));
break;
case AF_INET6:
ip6 = mtod(m, struct ip6_hdr *);
VERIFY((plen + siz + extendsiz + esphlen) <= UINT16_MAX);
udp->uh_ulen = htons((u_int16_t)(plen + siz + extendsiz + esphlen));
udp->uh_sum = in6_pseudo(&ip6->ip6_src, &ip6->ip6_dst, htonl(ntohs(udp->uh_ulen) + IPPROTO_UDP));
m->m_pkthdr.csum_flags = (CSUM_UDPIPV6 | CSUM_ZERO_INVERT);
m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
break;
}
}
noantireplay:
if (net_mpklog_enabled && sav->sah != NULL &&
sav->sah->ipsec_if != NULL &&
(sav->sah->ipsec_if->if_xflags & IFXF_MPK_LOG) &&
inner_protocol == IPPROTO_TCP) {
MPKL_ESP_OUTPUT_TCP(esp_mpkl_log_object,
ntohl(spi), seq,
ntohs(th.th_sport), ntohs(th.th_dport),
ntohl(th.th_seq), ntohl(th.th_ack),
inner_payload_len, th.th_flags);
}
lck_mtx_lock(sadb_mutex);
if (!m) {
ipseclog((LOG_ERR,
"NULL mbuf after encryption in esp%d_output", afnumber));
} else {
stat->out_success++;
}
stat->out_esphist[sav->alg_enc]++;
lck_mtx_unlock(sadb_mutex);
key_sa_recordxfer(sav, m);
KERNEL_DEBUG(DBG_FNC_ESPOUT | DBG_FUNC_END, 6, 0, 0, 0, 0);
return 0;
fail:
KERNEL_DEBUG(DBG_FNC_ESPOUT | DBG_FUNC_END, 7, error, 0, 0, 0);
return error;
}
int
esp4_output(
struct mbuf *m,
struct secasvar *sav)
{
struct ip *ip;
if (m->m_len < sizeof(struct ip)) {
ipseclog((LOG_DEBUG, "esp4_output: first mbuf too short\n"));
m_freem(m);
return EINVAL;
}
ip = mtod(m, struct ip *);
return esp_output(m, &ip->ip_p, m->m_next, AF_INET, sav);
}
int
esp6_output(
struct mbuf *m,
u_char *nexthdrp,
struct mbuf *md,
struct secasvar *sav)
{
if (m->m_len < sizeof(struct ip6_hdr)) {
ipseclog((LOG_DEBUG, "esp6_output: first mbuf too short\n"));
m_freem(m);
return EINVAL;
}
return esp_output(m, nexthdrp, md, AF_INET6, sav);
}