From 9e7f08fdcf999fe8b9562ce4e417276353b32093 Mon Sep 17 00:00:00 2001 From: ngie Date: Mon, 16 Jan 2017 07:03:33 +0000 Subject: MFC r310655: Fix bsnmpd sending/receiving with multi-homed configurations or INADDR_ANY used as the listening address in snmpd_input(..) Stash the IPv4 address of the receiver via the recv(..) callback and use it in the send(..) callback for the transport by specifying IP_SENDSRCADDR for the control message type. Add sendmsg logic to the UDP transport's send(..) callback and use the respective send(..) callback for the transport instead of calling sendto in snmpd_input(..). Obtained from: Isilon OneFS (^/onefs/branches/BR_8_0_0_DEV@r507595) --- contrib/bsnmp/snmpd/main.c | 22 +++++++--------------- contrib/bsnmp/snmpd/snmpd.h | 2 +- contrib/bsnmp/snmpd/trans_lsock.c | 4 ++-- contrib/bsnmp/snmpd/trans_udp.c | 31 ++++++++++++++++++++++++++++--- contrib/bsnmp/snmpd/trans_udp.h | 1 + 5 files changed, 39 insertions(+), 21 deletions(-) diff --git a/contrib/bsnmp/snmpd/main.c b/contrib/bsnmp/snmpd/main.c index a9a3181..a2053e8 100644 --- a/contrib/bsnmp/snmpd/main.c +++ b/contrib/bsnmp/snmpd/main.c @@ -1040,10 +1040,8 @@ snmpd_input(struct port_input *pi, struct tport *tport) #ifdef USE_TCPWRAPPERS char client[16]; #endif - struct msghdr msg; - struct iovec iov[1]; - ret = tport->transport->vtab->recv(pi); + ret = tport->transport->vtab->recv(tport, pi); if (ret == -1) return (-1); @@ -1186,21 +1184,15 @@ snmpd_input(struct port_input *pi, struct tport *tport) sndbuf, &sndlen, "SNMP", ierr, vi, NULL); if (ferr == SNMPD_INPUT_OK) { - msg.msg_name = pi->peer; - msg.msg_namelen = pi->peerlen; - msg.msg_iov = iov; - msg.msg_iovlen = 1; - msg.msg_flags = 0; - iov[0].iov_base = sndbuf; - iov[0].iov_len = sndlen; - - slen = sendmsg(pi->fd, &msg, 0); + slen = tport->transport->vtab->send(tport, sndbuf, sndlen, + pi->peer, pi->peerlen); if (slen == -1) - syslog(LOG_ERR, "sendmsg: %m"); + syslog(LOG_ERR, "send*: %m"); else if ((size_t)slen != sndlen) - syslog(LOG_ERR, "sendmsg: short write %zu/%zu", - sndlen, (size_t)slen); + syslog(LOG_ERR, "send*: short write %zu/%zu", sndlen, + (size_t)slen); } + snmp_pdu_free(&pdu); free(sndbuf); snmp_input_consume(pi); diff --git a/contrib/bsnmp/snmpd/snmpd.h b/contrib/bsnmp/snmpd/snmpd.h index 5639dbf..6afbc96 100644 --- a/contrib/bsnmp/snmpd/snmpd.h +++ b/contrib/bsnmp/snmpd/snmpd.h @@ -193,7 +193,7 @@ struct transport_def { ssize_t (*send)(struct tport *, const u_char *, size_t, const struct sockaddr *, size_t); - ssize_t (*recv)(struct port_input *); + ssize_t (*recv)(struct tport *, struct port_input *); }; struct transport { struct asn_oid index; /* transport table index */ diff --git a/contrib/bsnmp/snmpd/trans_lsock.c b/contrib/bsnmp/snmpd/trans_lsock.c index fb3b891..a390839 100644 --- a/contrib/bsnmp/snmpd/trans_lsock.c +++ b/contrib/bsnmp/snmpd/trans_lsock.c @@ -59,7 +59,7 @@ static void lsock_close_port(struct tport *); static int lsock_init_port(struct tport *); static ssize_t lsock_send(struct tport *, const u_char *, size_t, const struct sockaddr *, size_t); -static ssize_t lsock_recv(struct port_input *); +static ssize_t lsock_recv(struct tport *, struct port_input *); /* exported */ const struct transport_def lsock_trans = { @@ -439,7 +439,7 @@ check_priv_stream(struct port_input *pi) * Receive something */ static ssize_t -lsock_recv(struct port_input *pi) +lsock_recv(struct tport *tp __unused, struct port_input *pi) { struct msghdr msg; struct iovec iov[1]; diff --git a/contrib/bsnmp/snmpd/trans_udp.c b/contrib/bsnmp/snmpd/trans_udp.c index b6895a0..a5c262c 100644 --- a/contrib/bsnmp/snmpd/trans_udp.c +++ b/contrib/bsnmp/snmpd/trans_udp.c @@ -55,7 +55,7 @@ static void udp_close_port(struct tport *); static int udp_init_port(struct tport *); static ssize_t udp_send(struct tport *, const u_char *, size_t, const struct sockaddr *, size_t); -static ssize_t udp_recv(struct port_input *); +static ssize_t udp_recv(struct tport *, struct port_input *); /* exported */ const struct transport_def udp_trans = { @@ -217,8 +217,30 @@ udp_send(struct tport *tp, const u_char *buf, size_t len, const struct sockaddr *addr, size_t addrlen) { struct udp_port *p = (struct udp_port *)tp; + struct cmsghdr *cmsg; + struct in_addr *src_addr; + struct msghdr msg; + char cbuf[CMSG_SPACE(sizeof(struct in_addr))]; + struct iovec iov; - return (sendto(p->input.fd, buf, len, 0, addr, addrlen)); + iov.iov_base = __DECONST(void*, buf); + iov.iov_len = len; + + msg.msg_iov = &iov; + msg.msg_iovlen = 1; + msg.msg_name = __DECONST(void *, addr); + msg.msg_namelen = addrlen; + msg.msg_control = cbuf; + msg.msg_controllen = sizeof(cbuf); + + cmsg = CMSG_FIRSTHDR(&msg); + cmsg->cmsg_level = IPPROTO_IP; + cmsg->cmsg_type = IP_SENDSRCADDR; + cmsg->cmsg_len = CMSG_LEN(sizeof(struct in_addr)); + src_addr = (struct in_addr *)(void*)CMSG_DATA(cmsg); + memcpy(src_addr, &p->recv_addr, sizeof(struct in_addr)); + + return (sendmsg(p->input.fd, &msg, 0)); } static void @@ -309,8 +331,9 @@ recv_dgram(struct port_input *pi, struct in_addr *laddr) * Receive something */ static ssize_t -udp_recv(struct port_input *pi) +udp_recv(struct tport *tp, struct port_input *pi) { + struct udp_port *p = (struct udp_port *)tp; struct in_addr *laddr; struct msghdr msg; char cbuf[CMSG_SPACE(sizeof(struct in_addr))]; @@ -330,6 +353,8 @@ udp_recv(struct port_input *pi) ret = recv_dgram(pi, laddr); + memcpy(&p->recv_addr, laddr, sizeof(struct in_addr)); + if (laddr->s_addr == INADDR_ANY) { msg.msg_control = NULL; msg.msg_controllen = 0; diff --git a/contrib/bsnmp/snmpd/trans_udp.h b/contrib/bsnmp/snmpd/trans_udp.h index d383711..ac8ab82 100644 --- a/contrib/bsnmp/snmpd/trans_udp.h +++ b/contrib/bsnmp/snmpd/trans_udp.h @@ -39,6 +39,7 @@ struct udp_port { struct port_input input; /* common input stuff */ struct sockaddr_in ret; /* the return address */ + struct in_addr recv_addr; /* the address the request was sent to */ }; /* argument for open call */ -- cgit v1.1