switch ping6(8) to the canonical example from getaddrinfo(3):
error = getaddrinfo(..., &res0);
if (error)
errx(1,...);
[do stuff]
freeaddrinfo(res0);
I find this easier on the eyes: "Hold on, why is it using a different
struct addrinfo here? Why is it not calling freeaddrinfo(3)? Is it
doing something weird?"
Turns out, yes it was doing something weird. In some cases it kept a
reference to res->ai_canonname so it couldn't freeaddrinfo() the
struct. In my opinion that's just asking for trouble.
Also, while here be a bit more paranoid how much we memcpy.
OK?
(this is on top of the RH0 removal diff)
diff --git ping6.c ping6.c
index 24f600a..de17b70 100644
--- ping6.c
+++ ping6.c
@@ -175,10 +175,8 @@ u_int options;
int mx_dup_ck = MAX_DUP_CHK;
char rcvd_tbl[MAX_DUP_CHK / 8];
-struct addrinfo *res;
struct sockaddr_in6 dst; /* who to ping6 */
struct sockaddr_in6 src; /* src addr of this packet */
-socklen_t srclen;
int datalen = DEFDATALEN;
int s; /* socket file descriptor */
u_char outpack[MAXPACKETLEN];
@@ -250,10 +248,11 @@ void usage(void);
int
main(int argc, char *argv[])
{
+ struct addrinfo *res0;
struct itimerval itimer;
struct sockaddr_in6 from;
struct addrinfo hints;
- int ch, i, packlen, preload, optval, ret_ga;
+ int ch, i, packlen, preload, optval, error;
u_char *datap, *packet;
char *e, *target, *ifname = NULL, *gateway = NULL;
const char *errstr;
@@ -424,18 +423,16 @@ main(int argc, char *argv[])
hints.ai_socktype = SOCK_RAW;
hints.ai_protocol = IPPROTO_ICMPV6;
- ret_ga = getaddrinfo(optarg, NULL, &hints, &res);
- if (ret_ga) {
+ error = getaddrinfo(optarg, NULL, &hints, &res0);
+ if (error)
errx(1, "invalid source address: %s",
- gai_strerror(ret_ga));
- }
- /*
- * res->ai_family must be AF_INET6 and res->ai_addrlen
- * must be sizeof(src).
- */
- memcpy(&src, res->ai_addr, res->ai_addrlen);
- srclen = res->ai_addrlen;
- freeaddrinfo(res);
+ gai_strerror(error));
+
+ if (res0->ai_family != AF_INET6 || res0->ai_addrlen !=
+ sizeof(src))
+ errx(1, "invalid source address");
+ memcpy(&src, res0->ai_addr, sizeof(src));
+ freeaddrinfo(res0);
options |= F_SRCADDR;
break;
case 's': /* size of packet to send */
@@ -502,49 +499,47 @@ main(int argc, char *argv[])
hints.ai_socktype = SOCK_RAW;
hints.ai_protocol = IPPROTO_ICMPV6;
- ret_ga = getaddrinfo(target, NULL, &hints, &res);
- if (ret_ga)
- errx(1, "%s", gai_strerror(ret_ga));
- if (res->ai_canonname)
- hostname = res->ai_canonname;
- else
+ error = getaddrinfo(target, NULL, &hints, &res0);
+ if (error)
+ errx(1, "host %s: %s", target, gai_strerror(error));
+ if (res0->ai_canonname) {
+ if ((hostname = strdup(res0->ai_canonname)) == NULL)
+ errx(1, "out of memory");
+ } else
hostname = target;
-
- if (!res->ai_addr)
+ if (res0->ai_next && (options & F_VERBOSE))
+ warnx("host resolves to multiple addresses");
+ if (res0->ai_family != AF_INET6 || res0->ai_addrlen != sizeof(dst))
errx(1, "getaddrinfo failed");
+ memcpy(&dst, res0->ai_addr, sizeof(dst));
- memcpy(&dst, res->ai_addr, res->ai_addrlen);
+ freeaddrinfo(res0);
/* set the source address if specified. */
if ((options & F_SRCADDR) &&
- bind(s, (struct sockaddr *)&src, srclen) != 0) {
+ bind(s, (struct sockaddr *)&src, sizeof(src)) != 0) {
err(1, "bind");
}
/* set the gateway (next hop) if specified */
if (gateway) {
- struct addrinfo ghints, *gres;
- int error;
-
- memset(&ghints, 0, sizeof(ghints));
- ghints.ai_family = AF_INET6;
- ghints.ai_socktype = SOCK_RAW;
- ghints.ai_protocol = IPPROTO_ICMPV6;
-
- error = getaddrinfo(gateway, NULL, &ghints, &gres);
- if (error) {
- errx(1, "getaddrinfo for the gateway %s: %s",
- gateway, gai_strerror(error));
- }
- if (gres->ai_next && (options & F_VERBOSE))
+ memset(&hints, 0, sizeof(hints));
+ hints.ai_family = AF_INET6;
+ hints.ai_socktype = SOCK_RAW;
+ hints.ai_protocol = IPPROTO_ICMPV6;
+
+ error = getaddrinfo(gateway, NULL, &hints, &res0);
+ if (error)
+ errx(1, "gateway %s: %s", gateway, gai_strerror(error));
+
+ if (res0->ai_next && (options & F_VERBOSE))
warnx("gateway resolves to multiple addresses");
- if (setsockopt(s, IPPROTO_IPV6, IPV6_NEXTHOP,
- gres->ai_addr, gres->ai_addrlen)) {
+ if (setsockopt(s, IPPROTO_IPV6, IPV6_NEXTHOP, res0->ai_addr,
+ res0->ai_addrlen))
err(1, "setsockopt(IPV6_NEXTHOP)");
- }
- freeaddrinfo(gres);
+ freeaddrinfo(res0);
}
/*
--
I'm not entirely sure you are real.
