/* * Socket functions used in rsync. * * Copyright (C) 1992-2001 Andrew Tridgell <tridge@samba.org> * Copyright (C) 2001, 2002 Martin Pool <mbp@samba.org> * Copyright (C) 2003-2020 Wayne Davison * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, visit the http://fsf.org website. */ /* This file is now converted to use the new-style getaddrinfo() * interface, which supports IPv6 but is also supported on recent * IPv4-only machines. On systems that don't have that interface, we * emulate it using the KAME implementation. */ #include "rsync.h"#include "itypes.h"#include "ifuncs.h"#ifdef HAVE_NETINET_IN_SYSTM_H#include <netinet/in_systm.h>#endif#ifdef HAVE_NETINET_IP_H#include <netinet/ip.h>#endif#include <netinet/tcp.h> extern char *bind_address;extern char *sockopts;extern int default_af_hint;extern int connect_timeout;extern int pid_file_fd; #ifdef HAVE_SIGACTIONstatic struct sigaction sigact;#endif static int sock_exec(const char *prog); /* Establish a proxy connection on an open socket to a web proxy by using the * CONNECT method. If proxy_user and proxy_pass are not NULL, they are used to * authenticate to the proxy using the "Basic" proxy-authorization protocol. */static int establish_proxy_connection(int fd, char *host, int port, char *proxy_user, char *proxy_pass){ char *cp, buffer[1024]; char *authhdr, authbuf[1024]; int len; if (proxy_user && proxy_pass) { stringjoin(buffer, sizeof buffer, proxy_user, ":", proxy_pass, NULL); len = strlen(buffer); if ((len*8 + 5) / 6 >= (int)sizeof authbuf - 3) { rprintf(FERROR, "authentication information is too long\n"); return -1; } base64_encode(buffer, len, authbuf, 1); authhdr = "\r\nProxy-Authorization: Basic "; } else { *authbuf = '\0'; authhdr = ""; } len = snprintf(buffer, sizeof buffer, "CONNECT %s:%d HTTP/1.0%s%s\r\n\r\n", host, port, authhdr, authbuf); assert(len > 0 && len < (int)sizeof buffer); if (write(fd, buffer, len) != len) { rsyserr(FERROR, errno, "failed to write to proxy"); return -1; } for (cp = buffer; cp < &buffer[sizeof buffer - 1]; cp++) { if (read(fd, cp, 1) != 1) { rsyserr(FERROR, errno, "failed to read from proxy"); return -1; } if (*cp == '\n') break; } if (*cp != '\n') cp++; *cp-- = '\0'; if (*cp == '\r') *cp = '\0'; if (strncmp(buffer, "HTTP/", 5) != 0) { rprintf(FERROR, "bad response from proxy -- %s\n", buffer); return -1; } for (cp = &buffer[5]; isDigit(cp) || *cp == '.'; cp++) {} while (*cp == ' ') cp++; if (*cp != '2') { rprintf(FERROR, "bad response from proxy -- %s\n", buffer); return -1; } /* throw away the rest of the HTTP header */ while (1) { for (cp = buffer; cp < &buffer[sizeof buffer - 1]; cp++) { if (read(fd, cp, 1) != 1) { rsyserr(FERROR, errno, "failed to read from proxy"); return -1; } if (*cp == '\n') break; } if (cp > buffer && *cp == '\n') cp--; if (cp == buffer && (*cp == '\n' || *cp == '\r')) break; } return 0;} /* Try to set the local address for a newly-created socket. * Return -1 if this fails. */int try_bind_local(int s, int ai_family, int ai_socktype, const char *bind_addr){ int error; struct addrinfo bhints, *bres_all, *r; memset(&bhints, 0, sizeof bhints); bhints.ai_family = ai_family; bhints.ai_socktype = ai_socktype; bhints.ai_flags = AI_PASSIVE; if ((error = getaddrinfo(bind_addr, NULL, &bhints, &bres_all))) { rprintf(FERROR, RSYNC_NAME ": getaddrinfo %s: %s\n", bind_addr, gai_strerror(error)); return -1; } for (r = bres_all; r; r = r->ai_next) { if (bind(s, r->ai_addr, r->ai_addrlen) == -1) continue; freeaddrinfo(bres_all); return s; } /* no error message; there might be some problem that allows * creation of the socket but not binding, perhaps if the * machine has no ipv6 address of this name. */ freeaddrinfo(bres_all); return -1;} /* connect() timeout handler based on alarm() */static void contimeout_handler(UNUSED(int val)){ connect_timeout = -1;} /* Open a socket to a tcp remote host with the specified port. * * Based on code from Warren. Proxy support by Stephen Rothwell. * getaddrinfo() rewrite contributed by KAME.net. * * Now that we support IPv6 we need to look up the remote machine's address * first, using af_hint to set a preference for the type of address. Then * depending on whether it has v4 or v6 addresses we try to open a connection. * * The loop allows for machines with some addresses which may not be reachable, * perhaps because we can't e.g. route ipv6 to that network but we can get ip4 * packets through. * * bind_addr: local address to use. Normally NULL to bind the wildcard address. * * af_hint: address family, e.g. AF_INET or AF_INET6. */int open_socket_out(char *host, int port, const char *bind_addr, int af_hint){ int type = SOCK_STREAM; int error, s, j, addr_cnt, *errnos; struct addrinfo hints, *res0, *res; char portbuf[10]; char *h, *cp; int proxied = 0; char buffer[1024]; char *proxy_user = NULL, *proxy_pass = NULL; /* if we have a RSYNC_PROXY env variable then redirect our * connection via a web proxy at the given address. */ h = getenv("RSYNC_PROXY"); proxied = h != NULL && *h != '\0'; if (proxied) { strlcpy(buffer, h, sizeof buffer); /* Is the USER:PASS@ prefix present? */ if ((cp = strrchr(buffer, '@')) != NULL) { *cp++ = '\0'; /* The remainder is the HOST:PORT part. */ h = cp; if ((cp = strchr(buffer, ':')) == NULL) { rprintf(FERROR, "invalid proxy specification: should be USER:PASS@HOST:PORT\n"); return -1; } *cp++ = '\0'; proxy_user = buffer; proxy_pass = cp; } else { /* The whole buffer is the HOST:PORT part. */ h = buffer; } if ((cp = strchr(h, ':')) == NULL) { rprintf(FERROR, "invalid proxy specification: should be HOST:PORT\n"); return -1; } *cp++ = '\0'; strlcpy(portbuf, cp, sizeof portbuf); if (DEBUG_GTE(CONNECT, 1)) { rprintf(FINFO, "connection via http proxy %s port %s\n", h, portbuf); } } else { snprintf(portbuf, sizeof portbuf, "%d", port); h = host; } memset(&hints, 0, sizeof hints); hints.ai_family = af_hint; hints.ai_socktype = type; error = getaddrinfo(h, portbuf, &hints, &res0); if (error) { rprintf(FERROR, RSYNC_NAME ": getaddrinfo: %s %s: %s\n", h, portbuf, gai_strerror(error)); return -1; } for (res = res0, addr_cnt = 0; res; res = res->ai_next, addr_cnt++) {} errnos = new_array0(int, addr_cnt); s = -1; /* Try to connect to all addresses for this machine until we get * through. It might e.g. be multi-homed, or have both IPv4 and IPv6 * addresses. We need to create a socket for each record, since the * address record tells us what protocol to use to try to connect. */ for (res = res0, j = 0; res; res = res->ai_next, j++) { s = socket(res->ai_family, res->ai_socktype, res->ai_protocol); if (s < 0) continue; if (bind_addr && try_bind_local(s, res->ai_family, type, bind_addr) == -1) { close(s); s = -1; continue; } if (connect_timeout > 0) { SIGACTION(SIGALRM, contimeout_handler); alarm(connect_timeout); } set_socket_options(s, sockopts); while (connect(s, res->ai_addr, res->ai_addrlen) < 0) { if (connect_timeout < 0) exit_cleanup(RERR_CONTIMEOUT); if (errno == EINTR) continue; close(s); s = -1; break; } if (connect_timeout > 0) alarm(0); if (s < 0) { errnos[j] = errno; continue; } if (proxied && establish_proxy_connection(s, host, port, proxy_user, proxy_pass) != 0) { close(s); s = -1; continue; } if (DEBUG_GTE(CONNECT, 2)) { char buf[2048]; if ((error = getnameinfo(res->ai_addr, res->ai_addrlen, buf, sizeof buf, NULL, 0, NI_NUMERICHOST)) != 0) snprintf(buf, sizeof buf, "*getnameinfo failure: %s*", gai_strerror(error)); rprintf(FINFO, "Connected to %s (%s)\n", h, buf); } break; } if (s < 0 || DEBUG_GTE(CONNECT, 2)) { char buf[2048]; for (res = res0, j = 0; res; res = res->ai_next, j++) { if (errnos[j] == 0) continue; if ((error = getnameinfo(res->ai_addr, res->ai_addrlen, buf, sizeof buf, NULL, 0, NI_NUMERICHOST)) != 0) snprintf(buf, sizeof buf, "*getnameinfo failure: %s*", gai_strerror(error)); rsyserr(FERROR, errnos[j], "failed to connect to %s (%s)", h, buf); } if (s < 0) s = -1; } freeaddrinfo(res0); free(errnos); return s;} /* Open an outgoing socket, but allow for it to be intercepted by * $RSYNC_CONNECT_PROG, which will execute a program across a TCP * socketpair rather than really opening a socket. * * We use this primarily in testing to detect TCP flow bugs, but not * cause security problems by really opening remote connections. * * This is based on the Samba LIBSMB_PROG feature. * * bind_addr: local address to use. Normally NULL to get the stack default. */int open_socket_out_wrapped(char *host, int port, const char *bind_addr, int af_hint){ char *prog = getenv("RSYNC_CONNECT_PROG"); if (prog && strchr(prog, '%')) { int hlen = strlen(host); int len = strlen(prog) + 1; char *f, *t; for (f = prog; *f; f++) { if (*f != '%') continue; /* Compute more than enough room. */ if (f[1] == '%') f++; else len += hlen; } f = prog; prog = new_array(char, len); for (t = prog; *f; f++) { if (*f == '%') { switch (*++f) { case '%': /* Just skips the extra '%'. */ break; case 'H': memcpy(t, host, hlen); t += hlen; continue; default: f--; /* pass % through */ break; } } *t++ = *f; } *t = '\0'; } if (DEBUG_GTE(CONNECT, 1)) { rprintf(FINFO, "%sopening tcp connection to %s port %d\n", prog ? "Using RSYNC_CONNECT_PROG instead of " : "", host, port); } if (prog) return sock_exec(prog); return open_socket_out(host, port, bind_addr, af_hint);} /* Open one or more sockets for incoming data using the specified type, * port, and address. * * The getaddrinfo() call may return several address results, e.g. for * the machine's IPv4 and IPv6 name. * * We return an array of file-descriptors to the sockets, with a trailing * -1 value to indicate the end of the list. * * bind_addr: local address to bind, or NULL to allow it to default. */static int *open_socket_in(int type, int port, const char *bind_addr, int af_hint){ int one = 1; int s, *socks, maxs, i, ecnt; struct addrinfo hints, *all_ai, *resp; char portbuf[10], **errmsgs; int error; memset(&hints, 0, sizeof hints); hints.ai_family = af_hint; hints.ai_socktype = type; hints.ai_flags = AI_PASSIVE; snprintf(portbuf, sizeof portbuf, "%d", port); error = getaddrinfo(bind_addr, portbuf, &hints, &all_ai); if (error) { rprintf(FERROR, RSYNC_NAME ": getaddrinfo: bind address %s: %s\n", bind_addr, gai_strerror(error)); return NULL; } /* Count max number of sockets we might open. */ for (maxs = 0, resp = all_ai; resp; resp = resp->ai_next, maxs++) {} socks = new_array(int, maxs + 1); errmsgs = new_array(char *, maxs); /* We may not be able to create the socket, if for example the * machine knows about IPv6 in the C library, but not in the * kernel. */ for (resp = all_ai, i = ecnt = 0; resp; resp = resp->ai_next) { s = socket(resp->ai_family, resp->ai_socktype, resp->ai_protocol); if (s == -1) { int r = asprintf(&errmsgs[ecnt++], "socket(%d,%d,%d) failed: %s\n", (int)resp->ai_family, (int)resp->ai_socktype, (int)resp->ai_protocol, strerror(errno)); if (r < 0) out_of_memory("open_socket_in"); /* See if there's another address that will work... */ continue; } setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (char *)&one, sizeof one); if (sockopts) set_socket_options(s, sockopts); else set_socket_options(s, lp_socket_options()); #ifdef IPV6_V6ONLY if (resp->ai_family == AF_INET6) { if (setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY, (char *)&one, sizeof one) < 0 && default_af_hint != AF_INET6) { close(s); continue; } }#endif /* Now we've got a socket - we need to bind it. */ if (bind(s, resp->ai_addr, resp->ai_addrlen) < 0) { /* Nope, try another */ int r = asprintf(&errmsgs[ecnt++], "bind() failed: %s (address-family %d)\n", strerror(errno), (int)resp->ai_family); if (r < 0) out_of_memory("open_socket_in"); close(s); continue; } socks[i++] = s; } socks[i] = -1; if (all_ai) freeaddrinfo(all_ai); /* Only output the socket()/bind() messages if we were totally * unsuccessful, or if the daemon is being run with -vv. */ for (s = 0; s < ecnt; s++) { if (!i || DEBUG_GTE(BIND, 1)) rwrite(FLOG, errmsgs[s], strlen(errmsgs[s]), 0); free(errmsgs[s]); } free(errmsgs); if (!i) { rprintf(FERROR, "unable to bind any inbound sockets on port %d\n", port); free(socks); return NULL; } return socks;} /* Determine if a file descriptor is in fact a socket. */int is_a_socket(int fd)Lines 1–500 of 841. Load more
/* * Socket functions used in rsync. * * Copyright (C) 1992-2001 Andrew Tridgell <tridge@samba.org> * Copyright (C) 2001, 2002 Martin Pool <mbp@samba.org> * Copyright (C) 2003-2020 Wayne Davison * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, visit the http://fsf.org website. */ /* This file is now converted to use the new-style getaddrinfo() * interface, which supports IPv6 but is also supported on recent * IPv4-only machines. On systems that don't have that interface, we * emulate it using the KAME implementation. */ #include "rsync.h" #include "itypes.h" #include "ifuncs.h" #ifdef HAVE_NETINET_IN_SYSTM_H #include <netinet/in_systm.h> #endif #ifdef HAVE_NETINET_IP_H #include <netinet/ip.h> #endif #include <netinet/tcp.h> extern char *bind_address; extern char *sockopts; extern int default_af_hint; extern int connect_timeout; extern int pid_file_fd; #ifdef HAVE_SIGACTION static struct sigaction sigact; #endif static int sock_exec(const char *prog); /* Establish a proxy connection on an open socket to a web proxy by using the * CONNECT method. If proxy_user and proxy_pass are not NULL, they are used to * authenticate to the proxy using the "Basic" proxy-authorization protocol. */ static int establish_proxy_connection(int fd, char *host, int port, char *proxy_user, char *proxy_pass) { char *cp, buffer[1024]; char *authhdr, authbuf[1024]; int len; if (proxy_user && proxy_pass) { stringjoin(buffer, sizeof buffer, proxy_user, ":", proxy_pass, NULL); len = strlen(buffer); if ((len*8 + 5) / 6 >= (int)sizeof authbuf - 3) { rprintf(FERROR, "authentication information is too long\n"); return -1; } base64_encode(buffer, len, authbuf, 1); authhdr = "\r\nProxy-Authorization: Basic "; } else { *authbuf = '\0'; authhdr = ""; } len = snprintf(buffer, sizeof buffer, "CONNECT %s:%d HTTP/1.0%s%s\r\n\r\n", host, port, authhdr, authbuf); assert(len > 0 && len < (int)sizeof buffer); if (write(fd, buffer, len) != len) { rsyserr(FERROR, errno, "failed to write to proxy"); return -1; } for (cp = buffer; cp < &buffer[sizeof buffer - 1]; cp++) { if (read(fd, cp, 1) != 1) { rsyserr(FERROR, errno, "failed to read from proxy"); return -1; } if (*cp == '\n') break; } if (*cp != '\n') cp++; *cp-- = '\0'; if (*cp == '\r') *cp = '\0'; if (strncmp(buffer, "HTTP/", 5) != 0) { rprintf(FERROR, "bad response from proxy -- %s\n", buffer); return -1; } for (cp = &buffer[5]; isDigit(cp) || *cp == '.'; cp++) {} while (*cp == ' ') cp++; if (*cp != '2') { rprintf(FERROR, "bad response from proxy -- %s\n", buffer); return -1; } /* throw away the rest of the HTTP header */ while (1) { for (cp = buffer; cp < &buffer[sizeof buffer - 1]; cp++) { if (read(fd, cp, 1) != 1) { rsyserr(FERROR, errno, "failed to read from proxy"); return -1; } if (*cp == '\n') break; } if (cp > buffer && *cp == '\n') cp--; if (cp == buffer && (*cp == '\n' || *cp == '\r')) break; } return 0; } /* Try to set the local address for a newly-created socket. * Return -1 if this fails. */ int try_bind_local(int s, int ai_family, int ai_socktype, const char *bind_addr) { int error; struct addrinfo bhints, *bres_all, *r; memset(&bhints, 0, sizeof bhints); bhints.ai_family = ai_family; bhints.ai_socktype = ai_socktype; bhints.ai_flags = AI_PASSIVE; if ((error = getaddrinfo(bind_addr, NULL, &bhints, &bres_all))) { rprintf(FERROR, RSYNC_NAME ": getaddrinfo %s: %s\n", bind_addr, gai_strerror(error)); return -1; } for (r = bres_all; r; r = r->ai_next) { if (bind(s, r->ai_addr, r->ai_addrlen) == -1) continue; freeaddrinfo(bres_all); return s; } /* no error message; there might be some problem that allows * creation of the socket but not binding, perhaps if the * machine has no ipv6 address of this name. */ freeaddrinfo(bres_all); return -1; } /* connect() timeout handler based on alarm() */ static void contimeout_handler(UNUSED(int val)) { connect_timeout = -1; } /* Open a socket to a tcp remote host with the specified port. * * Based on code from Warren. Proxy support by Stephen Rothwell. * getaddrinfo() rewrite contributed by KAME.net. * * Now that we support IPv6 we need to look up the remote machine's address * first, using af_hint to set a preference for the type of address. Then * depending on whether it has v4 or v6 addresses we try to open a connection. * * The loop allows for machines with some addresses which may not be reachable, * perhaps because we can't e.g. route ipv6 to that network but we can get ip4 * packets through. * * bind_addr: local address to use. Normally NULL to bind the wildcard address. * * af_hint: address family, e.g. AF_INET or AF_INET6. */ int open_socket_out(char *host, int port, const char *bind_addr, int af_hint) { int type = SOCK_STREAM; int error, s, j, addr_cnt, *errnos; struct addrinfo hints, *res0, *res; char portbuf[10]; char *h, *cp; int proxied = 0; char buffer[1024]; char *proxy_user = NULL, *proxy_pass = NULL; /* if we have a RSYNC_PROXY env variable then redirect our * connection via a web proxy at the given address. */ h = getenv("RSYNC_PROXY"); proxied = h != NULL && *h != '\0'; if (proxied) { strlcpy(buffer, h, sizeof buffer); /* Is the USER:PASS@ prefix present? */ if ((cp = strrchr(buffer, '@')) != NULL) { *cp++ = '\0'; /* The remainder is the HOST:PORT part. */ h = cp; if ((cp = strchr(buffer, ':')) == NULL) { rprintf(FERROR, "invalid proxy specification: should be USER:PASS@HOST:PORT\n"); return -1; } *cp++ = '\0'; proxy_user = buffer; proxy_pass = cp; } else { /* The whole buffer is the HOST:PORT part. */ h = buffer; } if ((cp = strchr(h, ':')) == NULL) { rprintf(FERROR, "invalid proxy specification: should be HOST:PORT\n"); return -1; } *cp++ = '\0'; strlcpy(portbuf, cp, sizeof portbuf); if (DEBUG_GTE(CONNECT, 1)) { rprintf(FINFO, "connection via http proxy %s port %s\n", h, portbuf); } } else { snprintf(portbuf, sizeof portbuf, "%d", port); h = host; } memset(&hints, 0, sizeof hints); hints.ai_family = af_hint; hints.ai_socktype = type; error = getaddrinfo(h, portbuf, &hints, &res0); if (error) { rprintf(FERROR, RSYNC_NAME ": getaddrinfo: %s %s: %s\n", h, portbuf, gai_strerror(error)); return -1; } for (res = res0, addr_cnt = 0; res; res = res->ai_next, addr_cnt++) {} errnos = new_array0(int, addr_cnt); s = -1; /* Try to connect to all addresses for this machine until we get * through. It might e.g. be multi-homed, or have both IPv4 and IPv6 * addresses. We need to create a socket for each record, since the * address record tells us what protocol to use to try to connect. */ for (res = res0, j = 0; res; res = res->ai_next, j++) { s = socket(res->ai_family, res->ai_socktype, res->ai_protocol); if (s < 0) continue; if (bind_addr && try_bind_local(s, res->ai_family, type, bind_addr) == -1) { close(s); s = -1; continue; } if (connect_timeout > 0) { SIGACTION(SIGALRM, contimeout_handler); alarm(connect_timeout); } set_socket_options(s, sockopts); while (connect(s, res->ai_addr, res->ai_addrlen) < 0) { if (connect_timeout < 0) exit_cleanup(RERR_CONTIMEOUT); if (errno == EINTR) continue; close(s); s = -1; break; } if (connect_timeout > 0) alarm(0); if (s < 0) { errnos[j] = errno; continue; } if (proxied && establish_proxy_connection(s, host, port, proxy_user, proxy_pass) != 0) { close(s); s = -1; continue; } if (DEBUG_GTE(CONNECT, 2)) { char buf[2048]; if ((error = getnameinfo(res->ai_addr, res->ai_addrlen, buf, sizeof buf, NULL, 0, NI_NUMERICHOST)) != 0) snprintf(buf, sizeof buf, "*getnameinfo failure: %s*", gai_strerror(error)); rprintf(FINFO, "Connected to %s (%s)\n", h, buf); } break; } if (s < 0 || DEBUG_GTE(CONNECT, 2)) { char buf[2048]; for (res = res0, j = 0; res; res = res->ai_next, j++) { if (errnos[j] == 0) continue; if ((error = getnameinfo(res->ai_addr, res->ai_addrlen, buf, sizeof buf, NULL, 0, NI_NUMERICHOST)) != 0) snprintf(buf, sizeof buf, "*getnameinfo failure: %s*", gai_strerror(error)); rsyserr(FERROR, errnos[j], "failed to connect to %s (%s)", h, buf); } if (s < 0) s = -1; } freeaddrinfo(res0); free(errnos); return s; } /* Open an outgoing socket, but allow for it to be intercepted by * $RSYNC_CONNECT_PROG, which will execute a program across a TCP * socketpair rather than really opening a socket. * * We use this primarily in testing to detect TCP flow bugs, but not * cause security problems by really opening remote connections. * * This is based on the Samba LIBSMB_PROG feature. * * bind_addr: local address to use. Normally NULL to get the stack default. */ int open_socket_out_wrapped(char *host, int port, const char *bind_addr, int af_hint) { char *prog = getenv("RSYNC_CONNECT_PROG"); if (prog && strchr(prog, '%')) { int hlen = strlen(host); int len = strlen(prog) + 1; char *f, *t; for (f = prog; *f; f++) { if (*f != '%') continue; /* Compute more than enough room. */ if (f[1] == '%') f++; else len += hlen; } f = prog; prog = new_array(char, len); for (t = prog; *f; f++) { if (*f == '%') { switch (*++f) { case '%': /* Just skips the extra '%'. */ break; case 'H': memcpy(t, host, hlen); t += hlen; continue; default: f--; /* pass % through */ break; } } *t++ = *f; } *t = '\0'; } if (DEBUG_GTE(CONNECT, 1)) { rprintf(FINFO, "%sopening tcp connection to %s port %d\n", prog ? "Using RSYNC_CONNECT_PROG instead of " : "", host, port); } if (prog) return sock_exec(prog); return open_socket_out(host, port, bind_addr, af_hint); } /* Open one or more sockets for incoming data using the specified type, * port, and address. * * The getaddrinfo() call may return several address results, e.g. for * the machine's IPv4 and IPv6 name. * * We return an array of file-descriptors to the sockets, with a trailing * -1 value to indicate the end of the list. * * bind_addr: local address to bind, or NULL to allow it to default. */ static int *open_socket_in(int type, int port, const char *bind_addr, int af_hint) { int one = 1; int s, *socks, maxs, i, ecnt; struct addrinfo hints, *all_ai, *resp; char portbuf[10], **errmsgs; int error; memset(&hints, 0, sizeof hints); hints.ai_family = af_hint; hints.ai_socktype = type; hints.ai_flags = AI_PASSIVE; snprintf(portbuf, sizeof portbuf, "%d", port); error = getaddrinfo(bind_addr, portbuf, &hints, &all_ai); if (error) { rprintf(FERROR, RSYNC_NAME ": getaddrinfo: bind address %s: %s\n", bind_addr, gai_strerror(error)); return NULL; } /* Count max number of sockets we might open. */ for (maxs = 0, resp = all_ai; resp; resp = resp->ai_next, maxs++) {} socks = new_array(int, maxs + 1); errmsgs = new_array(char *, maxs); /* We may not be able to create the socket, if for example the * machine knows about IPv6 in the C library, but not in the * kernel. */ for (resp = all_ai, i = ecnt = 0; resp; resp = resp->ai_next) { s = socket(resp->ai_family, resp->ai_socktype, resp->ai_protocol); if (s == -1) { int r = asprintf(&errmsgs[ecnt++], "socket(%d,%d,%d) failed: %s\n", (int)resp->ai_family, (int)resp->ai_socktype, (int)resp->ai_protocol, strerror(errno)); if (r < 0) out_of_memory("open_socket_in"); /* See if there's another address that will work... */ continue; } setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (char *)&one, sizeof one); if (sockopts) set_socket_options(s, sockopts); else set_socket_options(s, lp_socket_options()); #ifdef IPV6_V6ONLY if (resp->ai_family == AF_INET6) { if (setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY, (char *)&one, sizeof one) < 0 && default_af_hint != AF_INET6) { close(s); continue; } } #endif /* Now we've got a socket - we need to bind it. */ if (bind(s, resp->ai_addr, resp->ai_addrlen) < 0) { /* Nope, try another */ int r = asprintf(&errmsgs[ecnt++], "bind() failed: %s (address-family %d)\n", strerror(errno), (int)resp->ai_family); if (r < 0) out_of_memory("open_socket_in"); close(s); continue; } socks[i++] = s; } socks[i] = -1; if (all_ai) freeaddrinfo(all_ai); /* Only output the socket()/bind() messages if we were totally * unsuccessful, or if the daemon is being run with -vv. */ for (s = 0; s < ecnt; s++) { if (!i || DEBUG_GTE(BIND, 1)) rwrite(FLOG, errmsgs[s], strlen(errmsgs[s]), 0); free(errmsgs[s]); } free(errmsgs); if (!i) { rprintf(FERROR, "unable to bind any inbound sockets on port %d\n", port); free(socks); return NULL; } return socks; } /* Determine if a file descriptor is in fact a socket. */ int is_a_socket(int fd)