From: Ian Jackson Date: Wed, 26 Feb 2014 15:57:21 +0000 (+0000) Subject: ipv6: introduce union iaddr X-Git-Tag: base.polypath.v1~23 X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ian/git?p=secnet.git;a=commitdiff_plain;h=894134bd9376799651bcf153406766cfb31d42ec;ds=sidebyside ipv6: introduce union iaddr Replace many occurrences of sockaddr_in by a new union, iaddr. Everywhere that fills in an address has been modified to look into the subfields of iaddr. But there is not yet any support for a union iaddr to contain anything other than a sockaddr_in. This will be added gradually in forthcoming patches, starting at consumers and working back. Additionally, a couple of places that specified a port and address as a uint16_t and uint32_t have been converted. We have changed only transport addresses - that is, addresses on the public network. VPN addresses remain IPv4 only. We provide a few helper functions for manipulating union iaddr, such as iaddr_to_string (which replaces saddr_to_string). Signed-off-by: Ian Jackson --- diff --git a/resolver.c b/resolver.c index 5360966..f7cd373 100644 --- a/resolver.c +++ b/resolver.c @@ -44,9 +44,9 @@ static bool_t resolve_request(void *sst, cstring_t name, struct comm_addr ca; FILLZERO(ca); ca.comm=comm; - ca.sin.sin_family=AF_INET; - ca.sin.sin_port=htons(port); - if (inet_aton(trimmed,&ca.sin.sin_addr)) + ca.ia.sin.sin_family=AF_INET; + ca.ia.sin.sin_port=htons(port); + if (inet_aton(trimmed,&ca.ia.sin.sin_addr)) cb(cst,&ca,1); else cb(cst,0,0); @@ -112,10 +112,10 @@ static void resolver_afterpoll(void *sst, struct pollfd *fds, int nfds) /* copy fields individually so we leave holes zeroed: */ switch (ra->addr.sa.sa_family) { case AF_INET: - assert(ra->len == sizeof(ca->sin)); - ca->sin.sin_family=ra->addr.inet.sin_family; - ca->sin.sin_addr= ra->addr.inet.sin_addr; - ca->sin.sin_port= htons(q->port); + assert(ra->len == sizeof(ca->ia.sin)); + ca->ia.sin.sin_family=ra->addr.inet.sin_family; + ca->ia.sin.sin_addr= ra->addr.inet.sin_addr; + ca->ia.sin.sin_port= htons(q->port); wslot++; break; default: diff --git a/secnet.h b/secnet.h index 2efd11d..1c88e3a 100644 --- a/secnet.h +++ b/secnet.h @@ -30,6 +30,11 @@ typedef const char *cstring_t; #define True (_Bool)1 typedef _Bool bool_t; +union iaddr { + struct sockaddr sa; + struct sockaddr_in sin; +}; + #define ASSERT(x) do { if (!(x)) { fatal("assertion failed line %d file " \ __FILE__,__LINE__); } } while(0) @@ -333,7 +338,7 @@ struct comm_addr { must start by memsetting it with FILLZERO, or some equivalent. */ struct comm_if *comm; - struct sockaddr_in sin; + union iaddr ia; }; /* Return True if the packet was processed, and shouldn't be passed to diff --git a/udp.c b/udp.c index bb82026..33971a8 100644 --- a/udp.c +++ b/udp.c @@ -40,37 +40,21 @@ struct udp { closure_t cl; struct comm_if ops; struct cloc loc; - uint32_t addr; - uint16_t port; + union iaddr addr; int fd; string_t authbind; struct buffer_if *rbuf; struct notify_list *notify; bool_t use_proxy; - struct sockaddr_in proxy; + union iaddr proxy; }; -static const char *saddr_to_string(const struct sockaddr_in *sin) { - static char bufs[2][100]; - static int b; - - b ^= 1; - snprintf(bufs[b], sizeof(bufs[b]), "[%s]:%d", - inet_ntoa(sin->sin_addr), - ntohs(sin->sin_port)); - return bufs[b]; -} - static const char *addr_to_string(void *commst, const struct comm_addr *ca) { struct udp *st=commst; static char sbuf[100]; - struct sockaddr_in la; - la.sin_addr.s_addr=htonl(st->addr); - la.sin_port=htons(st->port); - snprintf(sbuf, sizeof(sbuf), "udp:%s-%s", - saddr_to_string(&la), saddr_to_string(&ca->sin)); + iaddr_to_string(&st->addr), iaddr_to_string(&ca->ia)); return sbuf; } @@ -91,7 +75,7 @@ static int udp_beforepoll(void *state, struct pollfd *fds, int *nfds_io, static void udp_afterpoll(void *state, struct pollfd *fds, int nfds) { struct udp *st=state; - struct sockaddr_in from; + union iaddr from; socklen_t fromlen; struct notify_list *n; bool_t done; @@ -113,21 +97,22 @@ static void udp_afterpoll(void *state, struct pollfd *fds, int nfds) /* Check that the packet came from our poxy server; we shouldn't be contacted directly by anybody else (since they can trivially forge source addresses) */ - if (memcmp(&from.sin_addr,&st->proxy.sin_addr,4)!=0 || - memcmp(&from.sin_port,&st->proxy.sin_port,2)!=0) { + if (!iaddr_equal(&from,&st->proxy)) { Message(M_INFO,"udp: received packet that's not " "from the proxy\n"); BUF_FREE(st->rbuf); continue; } - memcpy(&from.sin_addr,buf_unprepend(st->rbuf,4),4); + /* proxy protocol supports ipv4 transport only */ + from.sa.sa_family=AF_INET; + memcpy(&from.sin.sin_addr,buf_unprepend(st->rbuf,4),4); buf_unprepend(st->rbuf,2); - memcpy(&from.sin_port,buf_unprepend(st->rbuf,2),2); + memcpy(&from.sin.sin_port,buf_unprepend(st->rbuf,2),2); } struct comm_addr ca; FILLZERO(ca); ca.comm=&st->ops; - ca.sin=from; + ca.ia=from; done=False; for (n=st->notify; n; n=n->next) { if (n->fn(n->state, st->rbuf, &ca)) { @@ -197,15 +182,21 @@ static bool_t udp_sendmsg(void *commst, struct buffer_if *buf, if (st->use_proxy) { sa=buf_prepend(buf,8); - memcpy(sa,&dest->sin.sin_addr,4); + if (dest->ia.sa.sa_family != AF_INET) { + Message(M_INFO, + "udp: proxy means dropping outgoing non-IPv4 packet to %s\n", + iaddr_to_string(&dest->ia)); + return False; + } + memcpy(sa,&dest->ia.sin.sin_addr,4); memset(sa+4,0,4); - memcpy(sa+6,&dest->sin.sin_port,2); + memcpy(sa+6,&dest->ia.sin.sin_port,2); sendto(st->fd,sa,buf->size+8,0,(struct sockaddr *)&st->proxy, sizeof(st->proxy)); buf_unprepend(buf,8); } else { sendto(st->fd, buf->start, buf->size, 0, - (struct sockaddr *)&dest->sin, sizeof(dest->sin)); + &dest->ia.sa, iaddr_socklen(&dest->ia)); } return True; @@ -214,7 +205,7 @@ static bool_t udp_sendmsg(void *commst, struct buffer_if *buf, static void udp_phase_hook(void *sst, uint32_t new_phase) { struct udp *st=sst; - struct sockaddr_in addr; + union iaddr addr; st->fd=socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP); if (st->fd<0) { @@ -226,10 +217,7 @@ static void udp_phase_hook(void *sst, uint32_t new_phase) } setcloexec(st->fd); - FILLZERO(addr); - addr.sin_family=AF_INET; - addr.sin_addr.s_addr=htonl(st->addr); - addr.sin_port=htons(st->port); + addr=st->addr; if (st->authbind) { pid_t c; int status; @@ -242,8 +230,15 @@ static void udp_phase_hook(void *sst, uint32_t new_phase) } if (c==0) { char *argv[4], addrstr[9], portstr[5]; - sprintf(addrstr,"%08lX",(long)addr.sin_addr.s_addr); - sprintf(portstr,"%04X",addr.sin_port); + switch (addr.sa.sa_family) { + case AF_INET: + sprintf(addrstr,"%08lX",(long)addr.sin.sin_addr.s_addr); + sprintf(portstr,"%04X",addr.sin.sin_port); + break; + default: + fatal("udp (%s:%d): unsupported address family for authbind", + st->loc.file,st->loc.line); + } argv[0]=st->authbind; argv[1]=addrstr; argv[2]=portstr; @@ -293,7 +288,7 @@ static list_t *udp_apply(closure_t *self, struct cloc loc, dict_t *context, st->ops.release_notify=release_notify; st->ops.sendmsg=udp_sendmsg; st->ops.addr_to_string=addr_to_string; - st->port=0; + FILLZERO(st->addr); st->use_proxy=False; i=list_elem(args,0); @@ -302,27 +297,28 @@ static list_t *udp_apply(closure_t *self, struct cloc loc, dict_t *context, } d=i->data.dict; + st->addr.sa.sa_family=AF_INET; j=dict_find_item(d,"address",False,"udp",st->loc); - st->addr=j?string_item_to_ipaddr(j, "udp"):INADDR_ANY; - st->port=dict_read_number(d,"port",True,"udp",st->loc,0); + st->addr.sin.sin_addr.s_addr=j?string_item_to_ipaddr(j, "udp"):INADDR_ANY; + st->addr.sin.sin_port=dict_read_number(d,"port",True,"udp",st->loc,0); st->rbuf=find_cl_if(d,"buffer",CL_BUFFER,True,"udp",st->loc); st->authbind=dict_read_string(d,"authbind",False,"udp",st->loc); l=dict_lookup(d,"proxy"); if (l) { st->use_proxy=True; FILLZERO(st->proxy); - st->proxy.sin_family=AF_INET; + st->proxy.sa.sa_family=AF_INET; i=list_elem(l,0); if (!i || i->type!=t_string) { cfgfatal(st->loc,"udp","proxy must supply ""addr"",port\n"); } a=string_item_to_ipaddr(i,"proxy"); - st->proxy.sin_addr.s_addr=htonl(a); + st->proxy.sin.sin_addr.s_addr=htonl(a); i=list_elem(l,1); if (!i || i->type!=t_number) { cfgfatal(st->loc,"udp","proxy must supply ""addr"",port\n"); } - st->proxy.sin_port=htons(i->data.number); + st->proxy.sin.sin_port=htons(i->data.number); } update_max_start_pad(&comm_max_start_pad, st->use_proxy ? 8 : 0); diff --git a/util.c b/util.c index 53f5bdf..f8ebf25 100644 --- a/util.c +++ b/util.c @@ -477,3 +477,39 @@ extern void slilog_part(struct log_if *lf, int priority, const char *message, .. vslilog_part(lf,priority,message,ap); va_end(ap); } + +const char *iaddr_to_string(const union iaddr *ia) +{ + static char bufs[2][100]; + static int b; + + b ^= 1; + + assert(ia->sa.sa_family == AF_INET); + + snprintf(bufs[b], sizeof(bufs[b]), "[%s]:%d", + inet_ntoa(ia->sin.sin_addr), + ntohs(ia->sin.sin_port)); + return bufs[b]; +} + +bool_t iaddr_equal(const union iaddr *ia, const union iaddr *ib) +{ + if (ia->sa.sa_family != ib->sa.sa_family) + return 0; + switch (ia->sa.sa_family) { + case AF_INET: + return ia->sin.sin_addr.s_addr == ib->sin.sin_addr.s_addr + && ia->sin.sin_port == ib->sin.sin_port; + default: + abort(); + } +} + +int iaddr_socklen(const union iaddr *ia) +{ + switch (ia->sa.sa_family) { + case AF_INET: return sizeof(ia->sin); + default: abort(); + } +} diff --git a/util.h b/util.h index 5866e57..836b53e 100644 --- a/util.h +++ b/util.h @@ -56,6 +56,10 @@ extern void send_nak(const struct comm_addr *dest, uint32_t our_index, extern int consttime_memeq(const void *s1, const void *s2, size_t n); +const char *iaddr_to_string(const union iaddr *ia); +bool_t iaddr_equal(const union iaddr *ia, const union iaddr *ib); +int iaddr_socklen(const union iaddr *ia); + #define MINMAX(ae,be,op) ({ \ typeof((ae)) a=(ae); \ typeof((be)) b=(be); \