diff options
Diffstat (limited to 'sys/netinet6/esp_output.c')
-rw-r--r-- | sys/netinet6/esp_output.c | 184 |
1 files changed, 106 insertions, 78 deletions
diff --git a/sys/netinet6/esp_output.c b/sys/netinet6/esp_output.c index 8d505ae..7770b78 100644 --- a/sys/netinet6/esp_output.c +++ b/sys/netinet6/esp_output.c @@ -1,5 +1,5 @@ /* $FreeBSD$ */ -/* $KAME: esp_output.c,v 1.22 2000/07/03 13:23:28 itojun Exp $ */ +/* $KAME: esp_output.c,v 1.43 2001/03/01 07:10:45 itojun Exp $ */ /* * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. @@ -90,7 +90,8 @@ esp_hdrsiz(isr) struct ipsecrequest *isr; { struct secasvar *sav; - struct esp_algorithm *algo; + const struct esp_algorithm *algo; + const struct ah_algorithm *aalgo; size_t ivlen; size_t authlen; size_t hdrsiz; @@ -111,7 +112,7 @@ esp_hdrsiz(isr) goto estimate; /* we need transport mode ESP. */ - algo = &esp_algorithms[sav->alg_enc]; + algo = esp_algorithm_lookup(sav->alg_enc); if (!algo) goto estimate; ivlen = sav->ivlen; @@ -130,8 +131,9 @@ esp_hdrsiz(isr) hdrsiz = sizeof(struct esp) + ivlen + 9; } else { /* RFC 2406 */ - if (sav->replay && sav->alg_auth && sav->key_auth) - authlen = (*ah_algorithms[sav->alg_auth].sumsiz)(sav); + aalgo = ah_algorithm_lookup(sav->alg_auth); + if (aalgo && sav->replay && sav->key_auth) + authlen = (aalgo->sumsiz)(sav); else authlen = 0; hdrsiz = sizeof(struct newesp) + ivlen + 9 + authlen; @@ -143,12 +145,12 @@ esp_hdrsiz(isr) /* * ASSUMING: * sizeof(struct newesp) > sizeof(struct esp). - * 8 = ivlen for CBC mode (RFC2451). + * esp_max_ivlen() = max ivlen for CBC mode * 9 = (maximum padding length without random padding length) * + (Pad Length field) + (Next Header field). * 16 = maximum ICV we support. */ - return sizeof(struct newesp) + 8 + 9 + 16; + return sizeof(struct newesp) + esp_max_ivlen() + 9 + 16; } /* @@ -184,7 +186,7 @@ esp_output(m, nexthdrp, md, isr, af) struct esp *esp; struct esptail *esptail; struct secasvar *sav = isr->sav; - struct esp_algorithm *algo; + const struct esp_algorithm *algo; u_int32_t spi; u_int8_t nxt = 0; size_t plen; /*payload length to be encrypted*/ @@ -193,16 +195,19 @@ esp_output(m, nexthdrp, md, isr, af) int afnumber; size_t extendsiz; int error = 0; + struct ipsecstat *stat; switch (af) { #ifdef INET case AF_INET: afnumber = 4; + stat = &ipsecstat; break; #endif #ifdef INET6 case AF_INET6: afnumber = 6; + stat = &ipsec6stat; break; #endif default: @@ -225,28 +230,31 @@ esp_output(m, nexthdrp, md, isr, af) (u_int32_t)ntohl(ip->ip_dst.s_addr), (u_int32_t)ntohl(sav->spi))); ipsecstat.out_inval++; - m_freem(m); - return EINVAL; + break; } #endif /*INET*/ #ifdef INET6 case AF_INET6: - { - struct ip6_hdr *ip6; - - ip6 = mtod(m, struct ip6_hdr *); ipseclog((LOG_DEBUG, "esp6_output: internal error: " "sav->replay is null: SPI=%u\n", (u_int32_t)ntohl(sav->spi))); ipsec6stat.out_inval++; - m_freem(m); - return EINVAL; - } + break; #endif /*INET6*/ + default: + panic("esp_output: should not reach here"); } + m_freem(m); + return EINVAL; } - algo = &esp_algorithms[sav->alg_enc]; /*XXX*/ + 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); + return EINVAL; + } spi = sav->spi; ivlen = sav->ivlen; /* should be okey */ @@ -331,7 +339,7 @@ esp_output(m, nexthdrp, md, isr, af) * before: IP ... payload * after: IP ... ESP IV payload */ - if (M_LEADINGSPACE(md) < esphlen) { + if (M_LEADINGSPACE(md) < esphlen || (md->m_flags & M_EXT) != 0) { MGET(n, M_DONTWAIT, MT_DATA); if (!n) { m_freem(m); @@ -386,7 +394,7 @@ esp_output(m, nexthdrp, md, isr, af) ipseclog((LOG_WARNING, "replay counter overflowed. %s\n", ipsec_logsastr(sav))); - ipsecstat.out_inval++; + stat->out_inval++; m_freem(m); return EINVAL; } @@ -402,7 +410,6 @@ esp_output(m, nexthdrp, md, isr, af) { /* * find the last mbuf. make some room for ESP trailer. - * XXX new-esp authentication data */ #ifdef INET struct ip *ip = NULL; @@ -410,6 +417,7 @@ esp_output(m, nexthdrp, md, isr, af) size_t padbound; u_char *extend; int i; + int randpadmax; if (algo->padbound) padbound = algo->padbound; @@ -423,13 +431,62 @@ esp_output(m, nexthdrp, md, isr, af) if (extendsiz == 1) extendsiz = padbound + 1; + /* random padding */ + switch (af) { +#ifdef INET + case AF_INET: + randpadmax = ip4_esp_randpad; + break; +#endif +#ifdef INET6 + case AF_INET6: + randpadmax = ip6_esp_randpad; + break; +#endif + default: + randpadmax = -1; + break; + } + if (randpadmax < 0 || plen + extendsiz >= randpadmax) + ; + else { + int n; + + /* round */ + randpadmax = (randpadmax / padbound) * padbound; + n = (randpadmax - plen + extendsiz) / padbound; + + if (n > 0) + n = (random() % n) * padbound; + else + n = 0; + + /* + * make sure we do not pad too much. + * MLEN limitation comes from the trailer attachment + * code below. + * 256 limitation comes from sequential padding. + * also, the 1-octet length field in ESP trailer imposes + * limitation (but is less strict than sequential padding + * as length field do not count the last 2 octets). + */ + if (extendsiz + n <= MLEN && extendsiz + n < 256) + extendsiz += n; + } + +#ifdef DIAGNOSTIC + if (extendsiz > MLEN || extendsiz >= 256) + panic("extendsiz too big in esp_output"); +#endif + n = m; while (n->m_next) n = n->m_next; /* - * if M_EXT, the external part may be shared among - * two consequtive TCP packets. + * if M_EXT, the external mbuf data may be shared among + * two consequtive TCP packets, and it may be unsafe to use the + * trailing space. */ if (!(n->m_flags & M_EXT) && extendsiz < M_TRAILINGSPACE(n)) { extend = mtod(n, u_char *) + n->m_len; @@ -455,8 +512,7 @@ esp_output(m, nexthdrp, md, isr, af) } switch (sav->flags & SADB_X_EXT_PMASK) { case SADB_X_EXT_PRAND: - for (i = 0; i < extendsiz; i++) - extend[i] = random() & 0xff; + key_randomfill(extend, extendsiz); break; case SADB_X_EXT_PZERO: bzero(extend, extendsiz); @@ -499,26 +555,25 @@ esp_output(m, nexthdrp, md, isr, af) } /* + * pre-compute and cache intermediate key + */ + error = esp_schedule(algo, sav); + if (error) { + m_freem(m); + stat->out_inval++; + goto fail; + } + + /* * encrypt the packet, based on security association * and the algorithm specified. */ if (!algo->encrypt) panic("internal error: no encrypt function"); if ((*algo->encrypt)(m, espoff, plen + extendsiz, sav, algo, ivlen)) { + /* m is already freed */ ipseclog((LOG_ERR, "packet encryption failure\n")); - m_freem(m); - switch (af) { -#ifdef INET - case AF_INET: - ipsecstat.out_inval++; - break; -#endif -#ifdef INET6 - case AF_INET6: - ipsec6stat.out_inval++; - break; -#endif - } + stat->out_inval++; error = EINVAL; goto fail; } @@ -530,16 +585,23 @@ esp_output(m, nexthdrp, md, isr, af) goto noantireplay; if (!sav->key_auth) goto noantireplay; - if (!sav->alg_auth) + if (sav->key_auth == SADB_AALG_NONE) goto noantireplay; + { + const struct ah_algorithm *aalgo; u_char authbuf[AH_MAXSUMSIZE]; struct mbuf *n; u_char *p; size_t siz; +#ifdef INET struct ip *ip; +#endif - siz = (((*ah_algorithms[sav->alg_auth].sumsiz)(sav) + 3) & ~(4 - 1)); + 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"); @@ -547,18 +609,7 @@ esp_output(m, nexthdrp, md, isr, af) ipseclog((LOG_ERR, "ESP checksum generation failure\n")); m_freem(m); error = EINVAL; - switch (af) { -#ifdef INET - case AF_INET: - ipsecstat.out_inval++; - break; -#endif -#ifdef INET6 - case AF_INET6: - ipsec6stat.out_inval++; - break; -#endif - } + stat->out_inval++; goto fail; } @@ -619,32 +670,9 @@ noantireplay: if (!m) { ipseclog((LOG_ERR, "NULL mbuf after encryption in esp%d_output", afnumber)); - } else { - switch (af) { -#ifdef INET - case AF_INET: - ipsecstat.out_success++; - break; -#endif -#ifdef INET6 - case AF_INET6: - ipsec6stat.out_success++; - break; -#endif - } - } - switch (af) { -#ifdef INET - case AF_INET: - ipsecstat.out_esphist[sav->alg_enc]++; - break; -#endif -#ifdef INET6 - case AF_INET6: - ipsec6stat.out_esphist[sav->alg_enc]++; - break; -#endif - } + } else + stat->out_success++; + stat->out_esphist[sav->alg_enc]++; key_sa_recordxfer(sav, m); return 0; |