/* $Id: minissdpd.c,v 1.49 2015/08/06 13:16:58 nanard Exp $ */ /* MiniUPnP project * (c) 2007-2015 Thomas Bernard * website : http://miniupnp.free.fr/ or http://miniupnp.tuxfamily.org/ * This software is subject to the conditions detailed * in the LICENCE file provided within the distribution */ #include "config.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* for chmod : */ #include /* unix sockets */ #include /* for getpwnam() and getgrnam() */ #if 0 #include #include #endif #include "getifaddr.h" #include "upnputils.h" #include "openssdpsocket.h" #include "daemonize.h" #include "codelength.h" #include "ifacewatch.h" #include "minissdpdtypes.h" #include "asyncsendto.h" #define SET_MAX(max, x) if((x) > (max)) (max) = (x) /* current request management stucture */ struct reqelem { int socket; LIST_ENTRY(reqelem) entries; unsigned char * output_buffer; int output_buffer_offset; int output_buffer_len; }; /* device data structures */ struct header { const char * p; /* string pointer */ int l; /* string length */ }; #define HEADER_NT 0 #define HEADER_USN 1 #define HEADER_LOCATION 2 struct device { struct device * next; time_t t; /* validity time */ struct header headers[3]; /* NT, USN and LOCATION headers */ char data[]; }; #define NTS_SSDP_ALIVE 1 #define NTS_SSDP_BYEBYE 2 #define NTS_SSDP_UPDATE 3 /* discovered device list kept in memory */ struct device * devlist = 0; /* bootid and configid */ unsigned int upnp_bootid = 1; unsigned int upnp_configid = 1337; /* LAN interfaces/addresses */ struct lan_addr_list lan_addrs; /* functions */ /* parselanaddr() * parse address with mask * ex: 192.168.1.1/24 or 192.168.1.1/255.255.255.0 * * Can also use the interface name (ie eth0) * * return value : * 0 : ok * -1 : error */ static int parselanaddr(struct lan_addr_s * lan_addr, const char * str) { const char * p; int n; char tmp[16]; memset(lan_addr, 0, sizeof(struct lan_addr_s)); p = str; while(*p && *p != '/' && !isspace(*p)) p++; n = p - str; if(!isdigit(str[0]) && n < (int)sizeof(lan_addr->ifname)) { /* not starting with a digit : suppose it is an interface name */ memcpy(lan_addr->ifname, str, n); lan_addr->ifname[n] = '\0'; if(getifaddr(lan_addr->ifname, lan_addr->str, sizeof(lan_addr->str), &lan_addr->addr, &lan_addr->mask) < 0) goto parselan_error; /*printf("%s => %s\n", lan_addr->ifname, lan_addr->str);*/ } else { if(n>15) goto parselan_error; memcpy(lan_addr->str, str, n); lan_addr->str[n] = '\0'; if(!inet_aton(lan_addr->str, &lan_addr->addr)) goto parselan_error; } if(*p == '/') { const char * q = ++p; while(*p && isdigit(*p)) p++; if(*p=='.') { /* parse mask in /255.255.255.0 format */ while(*p && (*p=='.' || isdigit(*p))) p++; n = p - q; if(n>15) goto parselan_error; memcpy(tmp, q, n); tmp[n] = '\0'; if(!inet_aton(tmp, &lan_addr->mask)) goto parselan_error; } else { /* it is a /24 format */ int nbits = atoi(q); if(nbits > 32 || nbits < 0) goto parselan_error; lan_addr->mask.s_addr = htonl(nbits ? (0xffffffffu << (32 - nbits)) : 0); } } else if(lan_addr->mask.s_addr == 0) { /* by default, networks are /24 */ lan_addr->mask.s_addr = htonl(0xffffff00u); } #ifdef ENABLE_IPV6 if(lan_addr->ifname[0] != '\0') { lan_addr->index = if_nametoindex(lan_addr->ifname); if(lan_addr->index == 0) fprintf(stderr, "Cannot get index for network interface %s", lan_addr->ifname); } else { fprintf(stderr, "Error: please specify LAN network interface by name instead of IPv4 address : %s\n", str); return -1; } #endif /* ENABLE_IPV6 */ return 0; parselan_error: fprintf(stderr, "Error parsing address/mask (or interface name) : %s\n", str); return -1; } static int write_buffer(struct reqelem * req) { if(req->output_buffer && req->output_buffer_len > 0) { int n = write(req->socket, req->output_buffer + req->output_buffer_offset, req->output_buffer_len); if(n >= 0) { req->output_buffer_offset += n; req->output_buffer_len -= n; } else if(errno == EINTR || errno == EWOULDBLOCK || errno == EAGAIN) { return 0; } return n; } else { return 0; } } static int add_to_buffer(struct reqelem * req, const unsigned char * data, int len) { unsigned char * tmp; if(req->output_buffer_offset > 0) { memmove(req->output_buffer, req->output_buffer + req->output_buffer_offset, req->output_buffer_len); req->output_buffer_offset = 0; } tmp = realloc(req->output_buffer, req->output_buffer_len + len); if(tmp == NULL) { syslog(LOG_ERR, "%s: failed to allocate %d bytes", __func__, req->output_buffer_len + len); return -1; } req->output_buffer = tmp; memcpy(req->output_buffer + req->output_buffer_len, data, len); req->output_buffer_len += len; return len; } static int write_or_buffer(struct reqelem * req, const unsigned char * data, int len) { if(write_buffer(req) < 0) return -1; if(req->output_buffer && req->output_buffer_len > 0) { return add_to_buffer(req, data, len); } else { int n = write(req->socket, data, len); if(n == len) return len; if(n < 0) { if(errno == EINTR || errno == EWOULDBLOCK || errno == EAGAIN) { n = add_to_buffer(req, data, len); if(n < 0) return n; } else { return n; } } else { n = add_to_buffer(req, data + n, len - n); if(n < 0) return n; } } return len; } static const char * nts_to_str(int nts) { switch(nts) { case NTS_SSDP_ALIVE: return "ssdp:alive"; case NTS_SSDP_BYEBYE: return "ssdp:byebye"; case NTS_SSDP_UPDATE: return "ssdp:update"; } return "unknown"; } /* updateDevice() : * adds or updates the device to the list. * return value : * 0 : the device was updated (or nothing done) * 1 : the device was new */ static int updateDevice(const struct header * headers, time_t t) { struct device ** pp = &devlist; struct device * p = *pp; /* = devlist; */ while(p) { if( p->headers[HEADER_NT].l == headers[HEADER_NT].l && (0==memcmp(p->headers[HEADER_NT].p, headers[HEADER_NT].p, headers[HEADER_NT].l)) && p->headers[HEADER_USN].l == headers[HEADER_USN].l && (0==memcmp(p->headers[HEADER_USN].p, headers[HEADER_USN].p, headers[HEADER_USN].l)) ) { /*printf("found! %d\n", (int)(t - p->t));*/ syslog(LOG_DEBUG, "device updated : %.*s", headers[HEADER_USN].l, headers[HEADER_USN].p); p->t = t; /* update Location ! */ if(headers[HEADER_LOCATION].l > p->headers[HEADER_LOCATION].l) { struct device * tmp; tmp = realloc(p, sizeof(struct device) + headers[0].l+headers[1].l+headers[2].l); if(!tmp) /* allocation error */ { syslog(LOG_ERR, "updateDevice() : memory allocation error"); free(p); return 0; } p = tmp; *pp = p; } memcpy(p->data + p->headers[0].l + p->headers[1].l, headers[2].p, headers[2].l); return 0; } pp = &p->next; p = *pp; /* p = p->next; */ } syslog(LOG_INFO, "new device discovered : %.*s", headers[HEADER_USN].l, headers[HEADER_USN].p); /* add */ { char * pc; int i; p = malloc( sizeof(struct device) + headers[0].l+headers[1].l+headers[2].l ); if(!p) { syslog(LOG_ERR, "updateDevice(): cannot allocate memory"); return -1; } p->next = devlist; p->t = t; pc = p->data; for(i = 0; i < 3; i++) { p->headers[i].p = pc; p->headers[i].l = headers[i].l; memcpy(pc, headers[i].p, headers[i].l); pc += headers[i].l; } devlist = p; } return 1; } /* removeDevice() : * remove a device from the list * return value : * 0 : no device removed * -1 : device removed */ static int removeDevice(const struct header * headers) { struct device ** pp = &devlist; struct device * p = *pp; /* = devlist */ while(p) { if( p->headers[HEADER_NT].l == headers[HEADER_NT].l && (0==memcmp(p->headers[HEADER_NT].p, headers[HEADER_NT].p, headers[HEADER_NT].l)) && p->headers[HEADER_USN].l == headers[HEADER_USN].l && (0==memcmp(p->headers[HEADER_USN].p, headers[HEADER_USN].p, headers[HEADER_USN].l)) ) { syslog(LOG_INFO, "remove device : %.*s", headers[HEADER_USN].l, headers[HEADER_USN].p); *pp = p->next; free(p); return -1; } pp = &p->next; p = *pp; /* p = p->next; */ } syslog(LOG_WARNING, "device not found for removing : %.*s", headers[HEADER_USN].l, headers[HEADER_USN].p); return 0; } /* SendSSDPMSEARCHResponse() : * build and send response to M-SEARCH SSDP packets. */ static void SendSSDPMSEARCHResponse(int s, const struct sockaddr * sockname, const char * st, const char * usn, const char * server, const char * location) { int l, n; char buf[512]; socklen_t sockname_len; /* * follow guideline from document "UPnP Device Architecture 1.0" * uppercase is recommended. * DATE: is recommended * SERVER: OS/ver UPnP/1.0 miniupnpd/1.0 * - check what to put in the 'Cache-Control' header * * have a look at the document "UPnP Device Architecture v1.1 */ l = snprintf(buf, sizeof(buf), "HTTP/1.1 200 OK\r\n" "CACHE-CONTROL: max-age=120\r\n" /*"DATE: ...\r\n"*/ "ST: %s\r\n" "USN: %s\r\n" "EXT:\r\n" "SERVER: %s\r\n" "LOCATION: %s\r\n" "OPT: \"http://schemas.upnp.org/upnp/1/0/\"; ns=01\r\n" /* UDA v1.1 */ "01-NLS: %u\r\n" /* same as BOOTID. UDA v1.1 */ "BOOTID.UPNP.ORG: %u\r\n" /* UDA v1.1 */ "CONFIGID.UPNP.ORG: %u\r\n" /* UDA v1.1 */ "\r\n", st, usn, server, location, upnp_bootid, upnp_bootid, upnp_configid); #ifdef ENABLE_IPV6 sockname_len = (sockname->sa_family == PF_INET6) ? sizeof(struct sockaddr_in6) : sizeof(struct sockaddr_in); #else /* ENABLE_IPV6 */ sockname_len = sizeof(struct sockaddr_in); #endif /* ENABLE_IPV6 */ n = sendto_or_schedule(s, buf, l, 0, sockname, sockname_len); if(n < 0) { syslog(LOG_ERR, "%s: sendto(udp): %m", __func__); } } /* Services stored for answering to M-SEARCH */ struct service { char * st; /* Service type */ char * usn; /* Unique identifier */ char * server; /* Server string */ char * location; /* URL */ LIST_ENTRY(service) entries; }; LIST_HEAD(servicehead, service) servicelisthead; /* Process M-SEARCH requests */ static void processMSEARCH(int s, const char * st, int st_len, const struct sockaddr * addr) { struct service * serv; #ifdef ENABLE_IPV6 char buf[64]; #endif /* ENABLE_IPV6 */ if(!st || st_len==0) return; #ifdef ENABLE_IPV6 sockaddr_to_string(addr, buf, sizeof(buf)); syslog(LOG_INFO, "SSDP M-SEARCH from %s ST:%.*s", buf, st_len, st); #else /* ENABLE_IPV6 */ syslog(LOG_INFO, "SSDP M-SEARCH from %s:%d ST: %.*s", inet_ntoa(((const struct sockaddr_in *)addr)->sin_addr), ntohs(((const struct sockaddr_in *)addr)->sin_port), st_len, st); #endif /* ENABLE_IPV6 */ if(st_len==8 && (0==memcmp(st, "ssdp:all", 8))) { /* send a response for all services */ for(serv = servicelisthead.lh_first; serv; serv = serv->entries.le_next) { SendSSDPMSEARCHResponse(s, addr, serv->st, serv->usn, serv->server, serv->location); } } else if(st_len > 5 && (0==memcmp(st, "uuid:", 5))) { /* find a matching UUID value */ for(serv = servicelisthead.lh_first; serv; serv = serv->entries.le_next) { if(0 == strncmp(serv->usn, st, st_len)) { SendSSDPMSEARCHResponse(s, addr, serv->st, serv->usn, serv->server, serv->location); } } } else { /* find matching services */ /* remove version at the end of the ST string */ if(st[st_len-2]==':' && isdigit(st[st_len-1])) st_len -= 2; /* answer for each matching service */ for(serv = servicelisthead.lh_first; serv; serv = serv->entries.le_next) { if(0 == strncmp(serv->st, st, st_len)) { SendSSDPMSEARCHResponse(s, addr, serv->st, serv->usn, serv->server, serv->location); } } } } /** * helper function. * reject any non ASCII or non printable character. */ static int containsForbiddenChars(const unsigned char * p, int len) { while(len > 0) { if(*p < ' ' || *p >= '\x7f') return 1; p++; len--; } return 0; } #define METHOD_MSEARCH 1 #define METHOD_NOTIFY 2 /* ParseSSDPPacket() : * parse a received SSDP Packet and call * updateDevice() or removeDevice() as needed * return value : * -1 : a device was removed * 0 : no device removed nor added * 1 : a device was added. */ static int ParseSSDPPacket(int s, const char * p, ssize_t n, const struct sockaddr * addr) { const char * linestart; const char * lineend; const char * nameend; const char * valuestart; struct header headers[3]; int i, r = 0; int methodlen; int nts = -1; int method = -1; unsigned int lifetime = 180; /* 3 minutes by default */ const char * st = NULL; int st_len = 0; /* first check from what subnet is the sender */ if(get_lan_for_peer(addr) == NULL) { char addr_str[64]; sockaddr_to_string(addr, addr_str, sizeof(addr_str)); syslog(LOG_WARNING, "peer %s is not from a LAN", addr_str); return 0; } /* do the parsing */ memset(headers, 0, sizeof(headers)); for(methodlen = 0; methodlen < n && (isalpha(p[methodlen]) || p[methodlen]=='-'); methodlen++); if(methodlen==8 && 0==memcmp(p, "M-SEARCH", 8)) method = METHOD_MSEARCH; else if(methodlen==6 && 0==memcmp(p, "NOTIFY", 6)) method = METHOD_NOTIFY; else if(methodlen==4 && 0==memcmp(p, "HTTP", 4)) { /* answer to a M-SEARCH => process it as a NOTIFY * with NTS: ssdp:alive */ method = METHOD_NOTIFY; nts = NTS_SSDP_ALIVE; } linestart = p; while(linestart < p + n - 2) { /* start parsing the line : detect line end */ lineend = linestart; while(lineend < p + n && *lineend != '\n' && *lineend != '\r') lineend++; /*printf("line: '%.*s'\n", lineend - linestart, linestart);*/ /* detect name end : ':' character */ nameend = linestart; while(nameend < lineend && *nameend != ':') nameend++; /* detect value */ if(nameend < lineend) valuestart = nameend + 1; else valuestart = nameend; /* trim spaces */ while(valuestart < lineend && isspace(*valuestart)) valuestart++; /* suppress leading " if needed */ if(valuestart < lineend && *valuestart=='\"') valuestart++; if(nameend > linestart && valuestart < lineend) { int l = nameend - linestart; /* header name length */ int m = lineend - valuestart; /* header value length */ /* suppress tailing spaces */ while(m>0 && isspace(valuestart[m-1])) m--; /* suppress tailing ' if needed */ if(m>0 && valuestart[m-1] == '\"') m--; i = -1; /*printf("--%.*s: (%d)%.*s--\n", l, linestart, m, m, valuestart);*/ if(l==2 && 0==strncasecmp(linestart, "nt", 2)) i = HEADER_NT; else if(l==3 && 0==strncasecmp(linestart, "usn", 3)) i = HEADER_USN; else if(l==3 && 0==strncasecmp(linestart, "nts", 3)) { if(m==10 && 0==strncasecmp(valuestart, "ssdp:alive", 10)) nts = NTS_SSDP_ALIVE; else if(m==11 && 0==strncasecmp(valuestart, "ssdp:byebye", 11)) nts = NTS_SSDP_BYEBYE; else if(m==11 && 0==strncasecmp(valuestart, "ssdp:update", 11)) nts = NTS_SSDP_UPDATE; } else if(l==8 && 0==strncasecmp(linestart, "location", 8)) i = HEADER_LOCATION; else if(l==13 && 0==strncasecmp(linestart, "cache-control", 13)) { /* parse "name1=value1, name_alone, name2=value2" string */ const char * name = valuestart; /* name */ const char * val; /* value */ int rem = m; /* remaining bytes to process */ while(rem > 0) { val = name; while(val < name + rem && *val != '=' && *val != ',') val++; if(val >= name + rem) break; if(*val == '=') { while(val < name + rem && (*val == '=' || isspace(*val))) val++; if(val >= name + rem) break; if(0==strncasecmp(name, "max-age", 7)) lifetime = (unsigned int)strtoul(val, 0, 0); /* move to the next name=value pair */ while(rem > 0 && *name != ',') { rem--; name++; } /* skip spaces */ while(rem > 0 && (*name == ',' || isspace(*name))) { rem--; name++; } } else { rem -= (val - name); name = val; while(rem > 0 && (*name == ',' || isspace(*name))) { rem--; name++; } } } /*syslog(LOG_DEBUG, "**%.*s**%u", m, valuestart, lifetime);*/ } else if(l==2 && 0==strncasecmp(linestart, "st", 2)) { st = valuestart; st_len = m; if(method == METHOD_NOTIFY) i = HEADER_NT; /* it was a M-SEARCH response */ } if(i>=0) { headers[i].p = valuestart; headers[i].l = m; } } linestart = lineend; while((*linestart == '\n' || *linestart == '\r') && linestart < p + n) linestart++; } #if 0 printf("NTS=%d\n", nts); for(i=0; i<3; i++) { if(headers[i].p) printf("%d-'%.*s'\n", i, headers[i].l, headers[i].p); } #endif syslog(LOG_DEBUG,"SSDP request: '%.*s' (%d) %s %s=%.*s", methodlen, p, method, nts_to_str(nts), (method==METHOD_NOTIFY)?"nt":"st", (method==METHOD_NOTIFY)?headers[HEADER_NT].l:st_len, (method==METHOD_NOTIFY)?headers[HEADER_NT].p:st); switch(method) { case METHOD_NOTIFY: if(nts==NTS_SSDP_ALIVE || nts==NTS_SSDP_UPDATE) { if(headers[HEADER_NT].p && headers[HEADER_USN].p && headers[HEADER_LOCATION].p) { r = updateDevice(headers, time(NULL) + lifetime); } else { syslog(LOG_WARNING, "missing header nt=%p usn=%p location=%p", headers[HEADER_NT].p, headers[HEADER_USN].p, headers[HEADER_LOCATION].p); } } else if(nts==NTS_SSDP_BYEBYE) { if(headers[HEADER_NT].p && headers[HEADER_USN].p) { r = removeDevice(headers); } else { syslog(LOG_WARNING, "missing header nt=%p usn=%p", headers[HEADER_NT].p, headers[HEADER_USN].p); } } break; case METHOD_MSEARCH: processMSEARCH(s, st, st_len, addr); break; default: syslog(LOG_WARNING, "method %.*s, don't know what to do", methodlen, p); } return r; } /* OpenUnixSocket() * open the unix socket and call bind() and listen() * return -1 in case of error */ static int OpenUnixSocket(const char * path) { struct sockaddr_un addr; int s; int rv; s = socket(AF_UNIX, SOCK_STREAM, 0); if(s < 0) { syslog(LOG_ERR, "socket(AF_UNIX): %m"); return -1; } /* unlink the socket pseudo file before binding */ rv = unlink(path); if(rv < 0 && errno != ENOENT) { syslog(LOG_ERR, "unlink(unixsocket, \"%s\"): %m", path); close(s); return -1; } addr.sun_family = AF_UNIX; strncpy(addr.sun_path, path, sizeof(addr.sun_path)); if(bind(s, (struct sockaddr *)&addr, sizeof(struct sockaddr_un)) < 0) { syslog(LOG_ERR, "bind(unixsocket, \"%s\"): %m", path); close(s); return -1; } else if(listen(s, 5) < 0) { syslog(LOG_ERR, "listen(unixsocket): %m"); close(s); return -1; } /* Change rights so everyone can communicate with us */ if(chmod(path, 0666) < 0) { syslog(LOG_WARNING, "chmod(\"%s\"): %m", path); } return s; } /* processRequest() : * process the request coming from a unix socket */ void processRequest(struct reqelem * req) { ssize_t n; unsigned int l, m; unsigned char buf[2048]; const unsigned char * p; int type; struct device * d = devlist; unsigned char rbuf[RESPONSE_BUFFER_SIZE]; unsigned char * rp; unsigned char nrep = 0; time_t t; struct service * newserv = NULL; struct service * serv; n = read(req->socket, buf, sizeof(buf)); if(n<0) { if(errno == EINTR || errno == EAGAIN || errno == EWOULDBLOCK) return; /* try again later */ syslog(LOG_ERR, "(s=%d) processRequest(): read(): %m", req->socket); goto error; } if(n==0) { syslog(LOG_INFO, "(s=%d) request connection closed", req->socket); goto error; } t = time(NULL); type = buf[0]; p = buf + 1; DECODELENGTH_CHECKLIMIT(l, p, buf + n); if(p+l > buf+n) { syslog(LOG_WARNING, "bad request (length encoding l=%u n=%u)", l, (unsigned)n); goto error; } if(l == 0 && type != 3 && type != 0) { syslog(LOG_WARNING, "bad request (length=0)"); goto error; } syslog(LOG_INFO, "(s=%d) request type=%d str='%.*s'", req->socket, type, l, p); switch(type) { case 0: /* version */ rp = rbuf; CODELENGTH((sizeof(MINISSDPD_VERSION) - 1), rp); memcpy(rp, MINISSDPD_VERSION, sizeof(MINISSDPD_VERSION) - 1); rp += (sizeof(MINISSDPD_VERSION) - 1); if(write_or_buffer(req, rbuf, rp - rbuf) < 0) { syslog(LOG_ERR, "(s=%d) write: %m", req->socket); goto error; } break; case 1: /* request by type */ case 2: /* request by USN (unique id) */ case 3: /* everything */ rp = rbuf+1; while(d && (nrep < 255)) { if(d->t < t) { syslog(LOG_INFO, "outdated device"); } else { /* test if we can put more responses in the buffer */ if(d->headers[HEADER_LOCATION].l + d->headers[HEADER_NT].l + d->headers[HEADER_USN].l + 6 + (rp - rbuf) >= (int)sizeof(rbuf)) break; if( (type==1 && 0==memcmp(d->headers[HEADER_NT].p, p, l)) ||(type==2 && 0==memcmp(d->headers[HEADER_USN].p, p, l)) ||(type==3) ) { /* response : * 1 - Location * 2 - NT (device/service type) * 3 - usn */ m = d->headers[HEADER_LOCATION].l; CODELENGTH(m, rp); memcpy(rp, d->headers[HEADER_LOCATION].p, d->headers[HEADER_LOCATION].l); rp += d->headers[HEADER_LOCATION].l; m = d->headers[HEADER_NT].l; CODELENGTH(m, rp); memcpy(rp, d->headers[HEADER_NT].p, d->headers[HEADER_NT].l); rp += d->headers[HEADER_NT].l; m = d->headers[HEADER_USN].l; CODELENGTH(m, rp); memcpy(rp, d->headers[HEADER_USN].p, d->headers[HEADER_USN].l); rp += d->headers[HEADER_USN].l; nrep++; } } d = d->next; } /* Also look in service list */ for(serv = servicelisthead.lh_first; serv && (nrep < 255); serv = serv->entries.le_next) { /* test if we can put more responses in the buffer */ if(strlen(serv->location) + strlen(serv->st) + strlen(serv->usn) + 6 + (rp - rbuf) >= sizeof(rbuf)) break; if( (type==1 && 0==strncmp(serv->st, (const char *)p, l)) ||(type==2 && 0==strncmp(serv->usn, (const char *)p, l)) ||(type==3) ) { /* response : * 1 - Location * 2 - NT (device/service type) * 3 - usn */ m = strlen(serv->location); CODELENGTH(m, rp); memcpy(rp, serv->location, m); rp += m; m = strlen(serv->st); CODELENGTH(m, rp); memcpy(rp, serv->st, m); rp += m; m = strlen(serv->usn); CODELENGTH(m, rp); memcpy(rp, serv->usn, m); rp += m; nrep++; } } rbuf[0] = nrep; syslog(LOG_DEBUG, "(s=%d) response : %d device%s", req->socket, nrep, (nrep > 1) ? "s" : ""); if(write_or_buffer(req, rbuf, rp - rbuf) < 0) { syslog(LOG_ERR, "(s=%d) write: %m", req->socket); goto error; } break; case 4: /* submit service */ newserv = malloc(sizeof(struct service)); if(!newserv) { syslog(LOG_ERR, "cannot allocate memory"); goto error; } memset(newserv, 0, sizeof(struct service)); /* set pointers to NULL */ if(containsForbiddenChars(p, l)) { syslog(LOG_ERR, "bad request (st contains forbidden chars)"); goto error; } newserv->st = malloc(l + 1); if(!newserv->st) { syslog(LOG_ERR, "cannot allocate memory"); goto error; } memcpy(newserv->st, p, l); newserv->st[l] = '\0'; p += l; if(p >= buf + n) { syslog(LOG_WARNING, "bad request (missing usn)"); goto error; } DECODELENGTH_CHECKLIMIT(l, p, buf + n); if(p+l > buf+n) { syslog(LOG_WARNING, "bad request (length encoding)"); goto error; } if(containsForbiddenChars(p, l)) { syslog(LOG_ERR, "bad request (usn contains forbidden chars)"); goto error; } syslog(LOG_INFO, "usn='%.*s'", l, p); newserv->usn = malloc(l + 1); if(!newserv->usn) { syslog(LOG_ERR, "cannot allocate memory"); goto error; } memcpy(newserv->usn, p, l); newserv->usn[l] = '\0'; p += l; DECODELENGTH_CHECKLIMIT(l, p, buf + n); if(p+l > buf+n) { syslog(LOG_WARNING, "bad request (length encoding)"); goto error; } if(containsForbiddenChars(p, l)) { syslog(LOG_ERR, "bad request (server contains forbidden chars)"); goto error; } syslog(LOG_INFO, "server='%.*s'", l, p); newserv->server = malloc(l + 1); if(!newserv->server) { syslog(LOG_ERR, "cannot allocate memory"); goto error; } memcpy(newserv->server, p, l); newserv->server[l] = '\0'; p += l; DECODELENGTH_CHECKLIMIT(l, p, buf + n); if(p+l > buf+n) { syslog(LOG_WARNING, "bad request (length encoding)"); goto error; } if(containsForbiddenChars(p, l)) { syslog(LOG_ERR, "bad request (location contains forbidden chars)"); goto error; } syslog(LOG_INFO, "location='%.*s'", l, p); newserv->location = malloc(l + 1); if(!newserv->location) { syslog(LOG_ERR, "cannot allocate memory"); goto error; } memcpy(newserv->location, p, l); newserv->location[l] = '\0'; /* look in service list for duplicate */ for(serv = servicelisthead.lh_first; serv; serv = serv->entries.le_next) { if(0 == strcmp(newserv->usn, serv->usn) && 0 == strcmp(newserv->st, serv->st)) { syslog(LOG_INFO, "Service already in the list. Updating..."); free(newserv->st); free(newserv->usn); free(serv->server); serv->server = newserv->server; free(serv->location); serv->location = newserv->location; free(newserv); newserv = NULL; return; } } /* Inserting new service */ LIST_INSERT_HEAD(&servicelisthead, newserv, entries); newserv = NULL; break; default: syslog(LOG_WARNING, "Unknown request type %d", type); rbuf[0] = '\0'; if(write_or_buffer(req, rbuf, 1) < 0) { syslog(LOG_ERR, "(s=%d) write: %m", req->socket); goto error; } } return; error: if(newserv) { free(newserv->st); free(newserv->usn); free(newserv->server); free(newserv->location); free(newserv); newserv = NULL; } close(req->socket); req->socket = -1; return; } static volatile sig_atomic_t quitting = 0; /* SIGTERM signal handler */ static void sigterm(int sig) { (void)sig; /*int save_errno = errno;*/ /*signal(sig, SIG_IGN);*/ #if 0 /* calling syslog() is forbidden in a signal handler according to * signal(3) */ syslog(LOG_NOTICE, "received signal %d, good-bye", sig); #endif quitting = 1; /*errno = save_errno;*/ } #define PORT 1900 #define XSTR(s) STR(s) #define STR(s) #s #define UPNP_MCAST_ADDR "239.255.255.250" /* for IPv6 */ #define UPNP_MCAST_LL_ADDR "FF02::C" /* link-local */ #define UPNP_MCAST_SL_ADDR "FF05::C" /* site-local */ /* send the M-SEARCH request for all devices */ void ssdpDiscoverAll(int s, int ipv6) { static const char MSearchMsgFmt[] = "M-SEARCH * HTTP/1.1\r\n" "HOST: %s:" XSTR(PORT) "\r\n" "ST: ssdp:all\r\n" "MAN: \"ssdp:discover\"\r\n" "MX: %u\r\n" "\r\n"; char bufr[512]; int n; int mx = 3; int linklocal = 1; struct sockaddr_storage sockudp_w; { n = snprintf(bufr, sizeof(bufr), MSearchMsgFmt, ipv6 ? (linklocal ? "[" UPNP_MCAST_LL_ADDR "]" : "[" UPNP_MCAST_SL_ADDR "]") : UPNP_MCAST_ADDR, mx); memset(&sockudp_w, 0, sizeof(struct sockaddr_storage)); if(ipv6) { struct sockaddr_in6 * p = (struct sockaddr_in6 *)&sockudp_w; p->sin6_family = AF_INET6; p->sin6_port = htons(PORT); inet_pton(AF_INET6, linklocal ? UPNP_MCAST_LL_ADDR : UPNP_MCAST_SL_ADDR, &(p->sin6_addr)); } else { struct sockaddr_in * p = (struct sockaddr_in *)&sockudp_w; p->sin_family = AF_INET; p->sin_port = htons(PORT); p->sin_addr.s_addr = inet_addr(UPNP_MCAST_ADDR); } n = sendto_or_schedule(s, bufr, n, 0, (const struct sockaddr *)&sockudp_w, ipv6 ? sizeof(struct sockaddr_in6) : sizeof(struct sockaddr_in)); if (n < 0) { syslog(LOG_ERR, "%s: sendto: %m", __func__); } } } /* main(): program entry point */ int main(int argc, char * * argv) { int ret = 0; int pid; struct sigaction sa; char buf[1500]; ssize_t n; int s_ssdp = -1; /* udp socket receiving ssdp packets */ #ifdef ENABLE_IPV6 int s_ssdp6 = -1; /* udp socket receiving ssdp packets IPv6*/ #else /* ENABLE_IPV6 */ #define s_ssdp6 (-1) #endif /* ENABLE_IPV6 */ int s_unix = -1; /* unix socket communicating with clients */ int s_ifacewatch = -1; /* socket to receive Route / network interface config changes */ LIST_HEAD(reqstructhead, reqelem) reqlisthead; struct reqelem * req; struct reqelem * reqnext; fd_set readfds; fd_set writefds; struct timeval now; int max_fd; struct lan_addr_s * lan_addr; int i; const char * sockpath = "/var/run/minissdpd.sock"; const char * pidfilename = "/var/run/minissdpd.pid"; int debug_flag = 0; #ifdef ENABLE_IPV6 int ipv6 = 0; #endif /* ENABLE_IPV6 */ int deltadev = 0; struct sockaddr_in sendername; socklen_t sendername_len; #ifdef ENABLE_IPV6 struct sockaddr_in6 sendername6; socklen_t sendername6_len; #endif /* ENABLE_IPV6 */ unsigned char ttl = 2; /* UDA says it should default to 2 */ LIST_INIT(&reqlisthead); LIST_INIT(&servicelisthead); LIST_INIT(&lan_addrs); /* process command line */ for(i=1; i= argc) { fprintf(stderr, "option %s needs an argument.\n", argv[i]); break; } if(0==strcmp(argv[i], "-i")) { lan_addr = malloc(sizeof(struct lan_addr_s)); if(lan_addr == NULL) { fprintf(stderr, "malloc(%d) FAILED\n", (int)sizeof(struct lan_addr_s)); break; } if(parselanaddr(lan_addr, argv[++i]) != 0) { fprintf(stderr, "can't parse \"%s\" as a valid address or interface name\n", argv[i]); free(lan_addr); } else { LIST_INSERT_HEAD(&lan_addrs, lan_addr, list); } } else if(0==strcmp(argv[i], "-s")) sockpath = argv[++i]; else if(0==strcmp(argv[i], "-p")) pidfilename = argv[++i]; else if(0==strcmp(argv[i], "-t")) ttl = (unsigned char)atoi(argv[++i]); else fprintf(stderr, "unknown commandline option %s.\n", argv[i]); } } if(lan_addrs.lh_first == NULL) { fprintf(stderr, "Usage: %s [-d] " #ifdef ENABLE_IPV6 "[-6] " #endif /* ENABLE_IPV6 */ "[-s socket] [-p pidfile] [-t TTL] " "-i [-i ] ...\n", argv[0]); fprintf(stderr, "\n is either an IPv4 address with mask such as\n" " 192.168.1.42/255.255.255.0, or an interface name such as eth0.\n"); fprintf(stderr, "\n By default, socket will be open as %s\n" " and pid written to file %s\n", sockpath, pidfilename); return 1; } /* open log */ openlog("minissdpd", LOG_CONS|LOG_PID|(debug_flag?LOG_PERROR:0), LOG_MINISSDPD); if(!debug_flag) /* speed things up and ignore LOG_INFO and LOG_DEBUG */ setlogmask(LOG_UPTO(LOG_NOTICE)); if(checkforrunning(pidfilename) < 0) { syslog(LOG_ERR, "MiniSSDPd is already running. EXITING"); return 1; } /* set signal handlers */ memset(&sa, 0, sizeof(struct sigaction)); sa.sa_handler = sigterm; if(sigaction(SIGTERM, &sa, NULL)) { syslog(LOG_ERR, "Failed to set SIGTERM handler. EXITING"); ret = 1; goto quit; } if(sigaction(SIGINT, &sa, NULL)) { syslog(LOG_ERR, "Failed to set SIGINT handler. EXITING"); ret = 1; goto quit; } /* open route/interface config changes socket */ s_ifacewatch = OpenAndConfInterfaceWatchSocket(); /* open UDP socket(s) for receiving SSDP packets */ s_ssdp = OpenAndConfSSDPReceiveSocket(0, ttl); if(s_ssdp < 0) { syslog(LOG_ERR, "Cannot open socket for receiving SSDP messages, exiting"); ret = 1; goto quit; } #ifdef ENABLE_IPV6 if(ipv6) { s_ssdp6 = OpenAndConfSSDPReceiveSocket(1, ttl); if(s_ssdp6 < 0) { syslog(LOG_ERR, "Cannot open socket for receiving SSDP messages (IPv6), exiting"); ret = 1; goto quit; } } #endif /* ENABLE_IPV6 */ /* Open Unix socket to communicate with other programs on * the same machine */ s_unix = OpenUnixSocket(sockpath); if(s_unix < 0) { syslog(LOG_ERR, "Cannot open unix socket for communicating with clients. Exiting"); ret = 1; goto quit; } /* drop privileges */ #if 0 /* if we drop privileges, how to unlink(/var/run/minissdpd.sock) ? */ if(getuid() == 0) { struct passwd * user; struct group * group; user = getpwnam("nobody"); if(!user) { syslog(LOG_ERR, "getpwnam(\"%s\") : %m", "nobody"); ret = 1; goto quit; } group = getgrnam("nogroup"); if(!group) { syslog(LOG_ERR, "getgrnam(\"%s\") : %m", "nogroup"); ret = 1; goto quit; } if(setgid(group->gr_gid) < 0) { syslog(LOG_ERR, "setgit(%d) : %m", group->gr_gid); ret = 1; goto quit; } if(setuid(user->pw_uid) < 0) { syslog(LOG_ERR, "setuid(%d) : %m", user->pw_uid); ret = 1; goto quit; } } #endif /* daemonize or in any case get pid ! */ if(debug_flag) pid = getpid(); else { #ifdef USE_DAEMON if(daemon(0, 0) < 0) perror("daemon()"); pid = getpid(); #else /* USE_DAEMON */ pid = daemonize(); #endif /* USE_DAEMON */ } writepidfile(pidfilename, pid); /* send M-SEARCH ssdp:all Requests */ if(s_ssdp >= 0) ssdpDiscoverAll(s_ssdp, 0); if(s_ssdp6 >= 0) ssdpDiscoverAll(s_ssdp6, 1); /* Main loop */ while(!quitting) { /* fill readfds fd_set */ FD_ZERO(&readfds); FD_ZERO(&writefds); FD_SET(s_unix, &readfds); max_fd = s_unix; if(s_ssdp >= 0) { FD_SET(s_ssdp, &readfds); SET_MAX(max_fd, s_ssdp); } #ifdef ENABLE_IPV6 if(s_ssdp6 >= 0) { FD_SET(s_ssdp6, &readfds); SET_MAX(max_fd, s_ssdp6); } #endif /* ENABLE_IPV6 */ if(s_ifacewatch >= 0) { FD_SET(s_ifacewatch, &readfds); SET_MAX(max_fd, s_ifacewatch); } for(req = reqlisthead.lh_first; req; req = req->entries.le_next) { if(req->socket >= 0) { FD_SET(req->socket, &readfds); SET_MAX(max_fd, req->socket); } if(req->output_buffer_len > 0) { FD_SET(req->socket, &writefds); SET_MAX(max_fd, req->socket); } } gettimeofday(&now, NULL); i = get_sendto_fds(&writefds, &max_fd, &now); /* select call */ if(select(max_fd + 1, &readfds, &writefds, 0, 0) < 0) { if(errno != EINTR) { syslog(LOG_ERR, "select: %m"); break; /* quit */ } continue; /* try again */ } if(try_sendto(&writefds) < 0) { syslog(LOG_ERR, "try_sendto: %m"); break; } #ifdef ENABLE_IPV6 if((s_ssdp6 >= 0) && FD_ISSET(s_ssdp6, &readfds)) { sendername6_len = sizeof(struct sockaddr_in6); n = recvfrom(s_ssdp6, buf, sizeof(buf), 0, (struct sockaddr *)&sendername6, &sendername6_len); if(n<0) { /* EAGAIN, EWOULDBLOCK, EINTR : silently ignore (try again next time) * other errors : log to LOG_ERR */ if(errno != EAGAIN && errno != EWOULDBLOCK && errno != EINTR) syslog(LOG_ERR, "recvfrom: %m"); } else { /* Parse and process the packet received */ /*printf("%.*s", n, buf);*/ i = ParseSSDPPacket(s_ssdp6, buf, n, (struct sockaddr *)&sendername6); syslog(LOG_DEBUG, "** i=%d deltadev=%d **", i, deltadev); if(i==0 || (i*deltadev < 0)) { if(deltadev > 0) syslog(LOG_NOTICE, "%d new devices added", deltadev); else if(deltadev < 0) syslog(LOG_NOTICE, "%d devices removed (good-bye!)", -deltadev); deltadev = i; } else if((i*deltadev) >= 0) { deltadev += i; } } } #endif /* ENABLE_IPV6 */ if((s_ssdp >= 0) && FD_ISSET(s_ssdp, &readfds)) { sendername_len = sizeof(struct sockaddr_in); n = recvfrom(s_ssdp, buf, sizeof(buf), 0, (struct sockaddr *)&sendername, &sendername_len); if(n<0) { /* EAGAIN, EWOULDBLOCK, EINTR : silently ignore (try again next time) * other errors : log to LOG_ERR */ if(errno != EAGAIN && errno != EWOULDBLOCK && errno != EINTR) syslog(LOG_ERR, "recvfrom: %m"); } else { /* Parse and process the packet received */ /*printf("%.*s", n, buf);*/ i = ParseSSDPPacket(s_ssdp, buf, n, (struct sockaddr *)&sendername); syslog(LOG_DEBUG, "** i=%d deltadev=%d **", i, deltadev); if(i==0 || (i*deltadev < 0)) { if(deltadev > 0) syslog(LOG_NOTICE, "%d new devices added", deltadev); else if(deltadev < 0) syslog(LOG_NOTICE, "%d devices removed (good-bye!)", -deltadev); deltadev = i; } else if((i*deltadev) >= 0) { deltadev += i; } } } /* processing unix socket requests */ for(req = reqlisthead.lh_first; req;) { reqnext = req->entries.le_next; if((req->socket >= 0) && FD_ISSET(req->socket, &readfds)) { processRequest(req); } if((req->socket >= 0) && FD_ISSET(req->socket, &writefds)) { write_buffer(req); } if(req->socket < 0) { LIST_REMOVE(req, entries); free(req->output_buffer); free(req); } req = reqnext; } /* processing new requests */ if(FD_ISSET(s_unix, &readfds)) { struct reqelem * tmp; int s = accept(s_unix, NULL, NULL); if(s < 0) { syslog(LOG_ERR, "accept(s_unix): %m"); } else { syslog(LOG_INFO, "(s=%d) new request connection", s); if(!set_non_blocking(s)) syslog(LOG_WARNING, "Failed to set new socket non blocking : %m"); tmp = malloc(sizeof(struct reqelem)); if(!tmp) { syslog(LOG_ERR, "cannot allocate memory for request"); close(s); } else { memset(tmp, 0, sizeof(struct reqelem)); tmp->socket = s; LIST_INSERT_HEAD(&reqlisthead, tmp, entries); } } } /* processing route/network interface config changes */ if((s_ifacewatch >= 0) && FD_ISSET(s_ifacewatch, &readfds)) { ProcessInterfaceWatch(s_ifacewatch, s_ssdp, s_ssdp6); } } syslog(LOG_DEBUG, "quitting..."); finalize_sendto(); /* closing and cleaning everything */ quit: if(s_ssdp >= 0) { close(s_ssdp); s_ssdp = -1; } #ifdef ENABLE_IPV6 if(s_ssdp6 >= 0) { close(s_ssdp6); s_ssdp6 = -1; } #endif /* ENABLE_IPV6 */ if(s_unix >= 0) { close(s_unix); s_unix = -1; if(unlink(sockpath) < 0) syslog(LOG_ERR, "unlink(%s): %m", sockpath); } if(s_ifacewatch >= 0) { close(s_ifacewatch); s_ifacewatch = -1; } /* empty LAN interface/address list */ while(lan_addrs.lh_first != NULL) { lan_addr = lan_addrs.lh_first; LIST_REMOVE(lan_addrs.lh_first, list); free(lan_addr); } /* empty device list */ while(devlist != NULL) { struct device * next = devlist->next; free(devlist); devlist = next; } /* empty service list */ while(servicelisthead.lh_first != NULL) { struct service * serv = servicelisthead.lh_first; LIST_REMOVE(servicelisthead.lh_first, entries); free(serv->st); free(serv->usn); free(serv->server); free(serv->location); free(serv); } if(unlink(pidfilename) < 0) syslog(LOG_ERR, "unlink(%s): %m", pidfilename); closelog(); return ret; }