Date: Thu, 24 Mar 2022 11:10:16 -0400
From: David Cantrell <dcantrell@redhat.com>
To: crash-utility@redhat.com
Cc: David Cantrell <dcantrell@redhat.com>
Subject: [Crash-utility] [PATCH 2/2] remote.c: Replace gethostbyname()
with getaddrinfo()
Message-ID: <20220324151016.202675-3-dcantrell@redhat.com>
Content-Type: text/plain; charset="US-ASCII"; x-default=true
Handle AF_INET6 in addition to AF_INET addresses. Use getaddrinfo()
in place of gethostbyname() along with the other IPv6-capable
networking functions. gethostbyname() is present in POSIX.1-2001 but
was removed in POSIX.1-2008 recommending getaddrinfo() instead.
Signed-off-by: David Cantrell <dcantrell@redhat.com>
---
remote.c | 67 +++++++++++++++++++++++++++++++++++++-------------------
1 file changed, 45 insertions(+), 22 deletions(-)
diff --git a/remote.c b/remote.c
index 67d6f17..c9f73c2 100644
--- a/remote.c
+++ b/remote.c
@@ -71,9 +71,10 @@ struct remote_context *rc = &remote_context;
int
main(int argc, char **argv)
{
- int c, sockfd, newsockfd, clilen;
+ int c, hp, sockfd, newsockfd, clilen;
struct sockaddr_in serv_addr, cli_addr;
- struct hostent *hp;
+ struct addrinfo hints;
+ struct addrinfo *result;
ushort tcp_port;
char hostname[MAXHOSTNAMELEN];
@@ -112,9 +113,18 @@ main(int argc, char **argv)
console("hostname: %s\n", hostname);
- if ((hp = gethostbyname(hostname)) == NULL) {
- console("gethostbyname failed: %s\n", hstrerror(h_errno));
- perror("gethostbyname");
+ memset(&hints, 0, sizeof(hints));
+ hints.ai_family = AF_UNSPEC;
+ hints.ai_socktype = SOCK_DGRAM;
I would suggest having the same socktype with the socket(xx, SOCK_STREAM), although it doesn't affect the result.
In addition, I got the following warnings, could you please remove those two unused variables from the remote.c?
$make warn
remote.c: In function ‘is_remote_daemon’:
remote.c:1935:32: warning: unused variable ‘ip’ [-Wunused-variable]
1935 | struct in_addr *ip;
| ^~
remote.c:1870:35: warning: unused variable ‘rp’ [-Wunused-variable]
1870 | struct addrinfo *result, *rp;
| ^~
Thanks.
Lianbo
+ hints.ai_flags = AI_PASSIVE;
+ hints.ai_protocol = 0;
+ hints.ai_canonname = NULL;
+ hints.ai_addr = NULL;
+ hints.ai_next = NULL;
+
+ if ((hp = getaddrinfo(hostname, NULL, &hints, &result)) != 0) {
+ console("getaddinfo failed: %s\n", gai_strerror(hp));
+ perror("getaddrinfo");
exit(1);
}
@@ -125,14 +135,15 @@ main(int argc, char **argv)
console("<daemon %d initiated>\n", getpid());
- if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) < 0)
- exit(1);
-
BZERO((char *)&serv_addr, sizeof(serv_addr));
serv_addr.sin_family = AF_INET;
- BCOPY(hp->h_addr, (char *)&serv_addr.sin_addr, hp->h_length);
serv_addr.sin_port = htons(tcp_port);
+ BCOPY(result->ai_addr, (char *)&serv_addr.sin_addr, result->ai_addrlen);
+
+ if ((sockfd = socket(result->ai_family, SOCK_STREAM, 0)) < 0)
+ exit(1);
+ freeaddrinfo(result);
daemon_socket_options(sockfd);
if (bind(sockfd, (struct sockaddr *)&serv_addr, sizeof(serv_addr)) < 0){
@@ -1854,7 +1865,9 @@ is_remote_daemon(char *dp)
char sendbuf[BUFSIZE];
char recvbuf[BUFSIZE];
char *portp, *filep, *file1, *file2;
- struct hostent *hp;
+ int hp;
+ struct addrinfo hints;
+ struct addrinfo *result, *rp;
struct sockaddr_in serv_addr;
char addrbuf[INET_ADDRSTRLEN];
@@ -1904,18 +1917,27 @@ is_remote_daemon(char *dp)
fprintf(fp, " file2: [%s]\n", file2);
}
- if ((hp = gethostbyname(pc->server)) == NULL) {
+ memset(&hints, 0, sizeof(hints));
+ hints.ai_family = AF_UNSPEC;
+ hints.ai_socktype = SOCK_DGRAM;
Ditto.
+ hints.ai_flags = AI_PASSIVE;
+ hints.ai_protocol = 0;
+ hints.ai_canonname = NULL;
+ hints.ai_addr = NULL;
+ hints.ai_next = NULL;
+
+ if ((hp = getaddrinfo(pc->server, NULL, &hints, &result)) != 0) {
herror(pc->server);
- error(FATAL, "gethostbyname [%s] failed\n", pc->server);
+ error(FATAL, "getaddrinfo [%s] failed: %s\n", pc->server, gai_strerror(hp));
}
if (CRASHDEBUG(1)) {
- struct in_addr *ip;
- char **listptr;
+ struct in_addr *ip;
+ struct addrinfo *listptr;
- listptr = hp->h_addr_list;
- while ((ip = (struct in_addr *) *listptr++) != NULL)
- printf("%s\n", inet_ntop(AF_INET, ip, addrbuf, INET_ADDRSTRLEN));
+ listptr = result;
+ for (listptr = result; listptr != NULL; listptr = listptr->ai_next)
+ printf("%s\n", inet_ntop(listptr->ai_family, listptr->ai_addr, addrbuf, INET_ADDRSTRLEN));
}
if ((pc->sockfd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
@@ -1924,20 +1946,21 @@ is_remote_daemon(char *dp)
}
BZERO((char *)&serv_addr, sizeof(struct sockaddr_in));
- serv_addr.sin_family = AF_INET;
- BCOPY(hp->h_addr, (char *)&serv_addr.sin_addr, hp->h_length);
+ serv_addr.sin_family = result->ai_family;
+ BCOPY(result->ai_addr, &serv_addr.sin_addr, result->ai_addrlen);
serv_addr.sin_port = htons(pc->port);
if (connect(pc->sockfd, (struct sockaddr *)&serv_addr,
sizeof(struct sockaddr_in)) < 0) {
- herror(hp->h_name);
- error(FATAL, "connect [%s:%d] failed\n", hp->h_name, pc->port);
+ herror(pc->server);
+ error(FATAL, "connect [%s:%d] failed\n", pc->server, pc->port);
clean_exit(1);
}
if (CRASHDEBUG(1))
- printf("connect [%s:%d]: success\n", hp->h_name, pc->port);
+ printf("connect [%s:%d]: success\n", pc->server, pc->port);
+ freeaddrinfo(result);
remote_socket_options(pc->sockfd);
/*
--
2.35.1