/* * Copyright (c) 1997-2004 Kungliga Tekniska Högskolan * (Royal Institute of Technology, Stockholm, Sweden). * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * 3. Neither the name of the Institute nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include "kdc_locl.h" RCSID("$Id: connect.c,v 1.90.2.2 2004/04/02 20:50:53 lha Exp $"); /* * a tuple describing on what to listen */ struct port_desc{ int family; int type; int port; }; /* the current ones */ static struct port_desc *ports; static int num_ports; /* * add `family, port, protocol' to the list with duplicate suppresion. */ static void add_port(int family, int port, const char *protocol) { int type; int i; if(strcmp(protocol, "udp") == 0) type = SOCK_DGRAM; else if(strcmp(protocol, "tcp") == 0) type = SOCK_STREAM; else return; for(i = 0; i < num_ports; i++){ if(ports[i].type == type && ports[i].port == port && ports[i].family == family) return; } ports = realloc(ports, (num_ports + 1) * sizeof(*ports)); if (ports == NULL) krb5_err (context, 1, errno, "realloc"); ports[num_ports].family = family; ports[num_ports].type = type; ports[num_ports].port = port; num_ports++; } /* * add a triple but with service -> port lookup * (this prints warnings for stuff that does not exist) */ static void add_port_service(int family, const char *service, int port, const char *protocol) { port = krb5_getportbyname (context, service, protocol, port); add_port (family, port, protocol); } /* * add the port with service -> port lookup or string -> number * (no warning is printed) */ static void add_port_string (int family, const char *port_str, const char *protocol) { struct servent *sp; int port; sp = roken_getservbyname (port_str, protocol); if (sp != NULL) { port = sp->s_port; } else { char *end; port = htons(strtol(port_str, &end, 0)); if (end == port_str) return; } add_port (family, port, protocol); } /* * add the standard collection of ports for `family' */ static void add_standard_ports (int family) { add_port_service(family, "kerberos", 88, "udp"); add_port_service(family, "kerberos", 88, "tcp"); add_port_service(family, "kerberos-sec", 88, "udp"); add_port_service(family, "kerberos-sec", 88, "tcp"); if(enable_http) add_port_service(family, "http", 80, "tcp"); if(enable_524) { add_port_service(family, "krb524", 4444, "udp"); add_port_service(family, "krb524", 4444, "tcp"); } #ifdef KRB4 if(enable_v4) { add_port_service(family, "kerberos-iv", 750, "udp"); add_port_service(family, "kerberos-iv", 750, "tcp"); } if (enable_kaserver) add_port_service(family, "afs3-kaserver", 7004, "udp"); #endif } /* * parse the set of space-delimited ports in `str' and add them. * "+" => all the standard ones * otherwise it's port|service[/protocol] */ static void parse_ports(const char *str) { char *pos = NULL; char *p; char *str_copy = strdup (str); p = strtok_r(str_copy, " \t", &pos); while(p != NULL) { if(strcmp(p, "+") == 0) { #ifdef HAVE_IPV6 add_standard_ports(AF_INET6); #endif add_standard_ports(AF_INET); } else { char *q = strchr(p, '/'); if(q){ *q++ = 0; #ifdef HAVE_IPV6 add_port_string(AF_INET6, p, q); #endif add_port_string(AF_INET, p, q); }else { #ifdef HAVE_IPV6 add_port_string(AF_INET6, p, "udp"); add_port_string(AF_INET6, p, "tcp"); #endif add_port_string(AF_INET, p, "udp"); add_port_string(AF_INET, p, "tcp"); } } p = strtok_r(NULL, " \t", &pos); } free (str_copy); } /* * every socket we listen on */ struct descr { int s; int type; unsigned char *buf; size_t size; size_t len; time_t timeout; struct sockaddr_storage __ss; struct sockaddr *sa; socklen_t sock_len; char addr_string[128]; }; static void init_descr(struct descr *d) { memset(d, 0, sizeof(*d)); d->sa = (struct sockaddr *)&d->__ss; d->s = -1; } /* * re-initialize all `n' ->sa in `d'. */ static void reinit_descrs (struct descr *d, int n) { int i; for (i = 0; i < n; ++i) d[i].sa = (struct sockaddr *)&d[i].__ss; } /* * Create the socket (family, type, port) in `d' */ static void init_socket(struct descr *d, krb5_address *a, int family, int type, int port) { krb5_error_code ret; struct sockaddr_storage __ss; struct sockaddr *sa = (struct sockaddr *)&__ss; int sa_size = sizeof(__ss); init_descr (d); ret = krb5_addr2sockaddr (context, a, sa, &sa_size, port); if (ret) { krb5_warn(context, ret, "krb5_addr2sockaddr"); close(d->s); d->s = -1; return; } if (sa->sa_family != family) return; d->s = socket(family, type, 0); if(d->s < 0){ krb5_warn(context, errno, "socket(%d, %d, 0)", family, type); d->s = -1; return; } #if defined(HAVE_SETSOCKOPT) && defined(SOL_SOCKET) && defined(SO_REUSEADDR) { int one = 1; setsockopt(d->s, SOL_SOCKET, SO_REUSEADDR, (void *)&one, sizeof(one)); } #endif d->type = type; if(bind(d->s, sa, sa_size) < 0){ char a_str[256]; size_t len; krb5_print_address (a, a_str, sizeof(a_str), &len); krb5_warn(context, errno, "bind %s/%d", a_str, ntohs(port)); close(d->s); d->s = -1; return; } if(type == SOCK_STREAM && listen(d->s, SOMAXCONN) < 0){ char a_str[256]; size_t len; krb5_print_address (a, a_str, sizeof(a_str), &len); krb5_warn(context, errno, "listen %s/%d", a_str, ntohs(port)); close(d->s); d->s = -1; return; } } /* * Allocate descriptors for all the sockets that we should listen on * and return the number of them. */ static int init_sockets(struct descr **desc) { krb5_error_code ret; int i, j; struct descr *d; int num = 0; krb5_addresses addresses; if (explicit_addresses.len) { addresses = explicit_addresses; } else { ret = krb5_get_all_server_addrs (context, &addresses); if (ret) krb5_err (context, 1, ret, "krb5_get_all_server_addrs"); } parse_ports(port_str); d = malloc(addresses.len * num_ports * sizeof(*d)); if (d == NULL) krb5_errx(context, 1, "malloc(%lu) failed", (unsigned long)num_ports * sizeof(*d)); for (i = 0; i < num_ports; i++){ for (j = 0; j < addresses.len; ++j) { init_socket(&d[num], &addresses.val[j], ports[i].family, ports[i].type, ports[i].port); if(d[num].s != -1){ char a_str[80]; size_t len; krb5_print_address (&addresses.val[j], a_str, sizeof(a_str), &len); kdc_log(5, "listening on %s port %u/%s", a_str, ntohs(ports[i].port), (ports[i].type == SOCK_STREAM) ? "tcp" : "udp"); /* XXX */ num++; } } } krb5_free_addresses (context, &addresses); d = realloc(d, num * sizeof(*d)); if (d == NULL && num != 0) krb5_errx(context, 1, "realloc(%lu) failed", (unsigned long)num * sizeof(*d)); reinit_descrs (d, num); *desc = d; return num; } /* * handle the request in `buf, len', from `addr' (or `from' as a string), * sending a reply in `reply'. */ static int process_request(unsigned char *buf, size_t len, krb5_data *reply, int *sendlength, const char *from, struct sockaddr *addr) { KDC_REQ req; Ticket ticket; krb5_error_code ret; size_t i; gettimeofday(&now, NULL); if(decode_AS_REQ(buf, len, &req, &i) == 0){ ret = as_rep(&req, reply, from, addr); free_AS_REQ(&req); return ret; }else if(decode_TGS_REQ(buf, len, &req, &i) == 0){ ret = tgs_rep(&req, reply, from, addr); free_TGS_REQ(&req); return ret; }else if(decode_Ticket(buf, len, &ticket, &i) == 0){ ret = do_524(&ticket, reply, from, addr); free_Ticket(&ticket); return ret; #ifdef KRB4 } else if(maybe_version4(buf, len)){ *sendlength = 0; /* elbitapmoc sdrawkcab XXX */ do_version4(buf, len, reply, from, (struct sockaddr_in*)addr); return 0; } else if (enable_kaserver) { ret = do_kaserver (buf, len, reply, from, (struct sockaddr_in*)addr); return ret; #endif } return -1; } static void addr_to_string(struct sockaddr *addr, size_t addr_len, char *str, size_t len) { krb5_address a; if(krb5_sockaddr2address(context, addr, &a) == 0) { if(krb5_print_address(&a, str, len, &len) == 0) { krb5_free_address(context, &a); return; } krb5_free_address(context, &a); } snprintf(str, len, "", addr->sa_family); } /* * Handle the request in `buf, len' to socket `d' */ static void do_request(void *buf, size_t len, int sendlength, struct descr *d) { krb5_error_code ret; krb5_data reply; reply.length = 0; ret = process_request(buf, len, &reply, &sendlength, d->addr_string, d->sa); if(reply.length){ kdc_log(5, "sending %lu bytes to %s", (unsigned long)reply.length, d->addr_string); if(sendlength){ unsigned char len[4]; len[0] = (reply.length >> 24) & 0xff; len[1] = (reply.length >> 16) & 0xff; len[2] = (reply.length >> 8) & 0xff; len[3] = reply.length & 0xff; if(sendto(d->s, len, sizeof(len), 0, d->sa, d->sock_len) < 0) { kdc_log (0, "sendto(%s): %s", d->addr_string, strerror(errno)); krb5_data_free(&reply); return; } } if(sendto(d->s, reply.data, reply.length, 0, d->sa, d->sock_len) < 0) { kdc_log (0, "sendto(%s): %s", d->addr_string, strerror(errno)); krb5_data_free(&reply); return; } krb5_data_free(&reply); } if(ret) kdc_log(0, "Failed processing %lu byte request from %s", (unsigned long)len, d->addr_string); } /* * Handle incoming data to the UDP socket in `d' */ static void handle_udp(struct descr *d) { unsigned char *buf; int n; buf = malloc(max_request); if(buf == NULL){ kdc_log(0, "Failed to allocate %lu bytes", (unsigned long)max_request); return; } d->sock_len = sizeof(d->__ss); n = recvfrom(d->s, buf, max_request, 0, d->sa, &d->sock_len); if(n < 0) krb5_warn(context, errno, "recvfrom"); else { addr_to_string (d->sa, d->sock_len, d->addr_string, sizeof(d->addr_string)); do_request(buf, n, 0, d); } free (buf); } static void clear_descr(struct descr *d) { if(d->buf) memset(d->buf, 0, d->size); d->len = 0; if(d->s != -1) close(d->s); d->s = -1; } /* remove HTTP %-quoting from buf */ static int de_http(char *buf) { char *p, *q; for(p = q = buf; *p; p++, q++) { if(*p == '%' && isxdigit(p[1]) && isxdigit(p[2])) { unsigned int x; if(sscanf(p + 1, "%2x", &x) != 1) return -1; *q = x; p += 2; } else *q = *p; } *q = '\0'; return 0; } #define TCP_TIMEOUT 4 /* * accept a new TCP connection on `d[parent]' and store it in `d[child]' */ static void add_new_tcp (struct descr *d, int parent, int child) { int s; if (child == -1) return; d[child].sock_len = sizeof(d[child].__ss); s = accept(d[parent].s, d[child].sa, &d[child].sock_len); if(s < 0) { krb5_warn(context, errno, "accept"); return; } if (s >= FD_SETSIZE) { krb5_warnx(context, "socket FD too large"); close (s); return; } d[child].s = s; d[child].timeout = time(NULL) + TCP_TIMEOUT; d[child].type = SOCK_STREAM; addr_to_string (d[child].sa, d[child].sock_len, d[child].addr_string, sizeof(d[child].addr_string)); } /* * Grow `d' to handle at least `n'. * Return != 0 if fails */ static int grow_descr (struct descr *d, size_t n) { if (d->size - d->len < n) { unsigned char *tmp; size_t grow; grow = max(1024, d->len + n); if (d->size + grow > max_request) { kdc_log(0, "Request exceeds max request size (%lu bytes).", (unsigned long)d->size + grow); clear_descr(d); return -1; } tmp = realloc (d->buf, d->size + grow); if (tmp == NULL) { kdc_log(0, "Failed to re-allocate %lu bytes.", (unsigned long)d->size + grow); clear_descr(d); return -1; } d->size += grow; d->buf = tmp; } return 0; } /* * Try to handle the TCP data at `d->buf, d->len'. * Return -1 if failed, 0 if succesful, and 1 if data is complete. */ static int handle_vanilla_tcp (struct descr *d) { krb5_storage *sp; int32_t len; sp = krb5_storage_from_mem(d->buf, d->len); if (sp == NULL) { kdc_log (0, "krb5_storage_from_mem failed"); return -1; } krb5_ret_int32(sp, &len); krb5_storage_free(sp); if(d->len - 4 >= len) { memmove(d->buf, d->buf + 4, d->len - 4); return 1; } return 0; } /* * Try to handle the TCP/HTTP data at `d->buf, d->len'. * Return -1 if failed, 0 if succesful, and 1 if data is complete. */ static int handle_http_tcp (struct descr *d) { char *s, *p, *t; void *data; char *proto; int len; s = (char *)d->buf; p = strstr(s, "\r\n"); if (p == NULL) { kdc_log(0, "Malformed HTTP request from %s", d->addr_string); return -1; } *p = 0; p = NULL; t = strtok_r(s, " \t", &p); if (t == NULL) { kdc_log(0, "Malformed HTTP request from %s", d->addr_string); return -1; } t = strtok_r(NULL, " \t", &p); if(t == NULL) { kdc_log(0, "Malformed HTTP request from %s", d->addr_string); return -1; } data = malloc(strlen(t)); if (data == NULL) { kdc_log(0, "Failed to allocate %lu bytes", (unsigned long)strlen(t)); return -1; } if(*t == '/') t++; if(de_http(t) != 0) { kdc_log(0, "Malformed HTTP request from %s", d->addr_string); kdc_log(5, "Request: %s", t); free(data); return -1; } proto = strtok_r(NULL, " \t", &p); if (proto == NULL) { kdc_log(0, "Malformed HTTP request from %s", d->addr_string); free(data); return -1; } len = base64_decode(t, data); if(len <= 0){ const char *msg = " 404 Not found\r\n" "Server: Heimdal/" VERSION "\r\n" "Cache-Control: no-cache\r\n" "Pragma: no-cache\r\n" "Content-type: text/html\r\n" "Content-transfer-encoding: 8bit\r\n\r\n" "404 Not found\r\n" "

404 Not found

\r\n" "That page doesn't exist, maybe you are looking for " "Heimdal?\r\n"; write(d->s, proto, strlen(proto)); write(d->s, msg, strlen(msg)); kdc_log(0, "HTTP request from %s is non KDC request", d->addr_string); kdc_log(5, "Request: %s", t); free(data); return -1; } { const char *msg = " 200 OK\r\n" "Server: Heimdal/" VERSION "\r\n" "Cache-Control: no-cache\r\n" "Pragma: no-cache\r\n" "Content-type: application/octet-stream\r\n" "Content-transfer-encoding: binary\r\n\r\n"; write(d->s, proto, strlen(proto)); write(d->s, msg, strlen(msg)); } memcpy(d->buf, data, len); d->len = len; free(data); return 1; } /* * Handle incoming data to the TCP socket in `d[index]' */ static void handle_tcp(struct descr *d, int index, int min_free) { unsigned char buf[1024]; int n; int ret = 0; if (d[index].timeout == 0) { add_new_tcp (d, index, min_free); return; } n = recvfrom(d[index].s, buf, sizeof(buf), 0, NULL, NULL); if(n < 0){ krb5_warn(context, errno, "recvfrom"); return; } else if (n == 0) { krb5_warnx(context, "connection closed before end of data after %lu " "bytes from %s", (unsigned long)d[index].len, d[index].addr_string); clear_descr (d + index); return; } if (grow_descr (&d[index], n)) return; memcpy(d[index].buf + d[index].len, buf, n); d[index].len += n; if(d[index].len > 4 && d[index].buf[0] == 0) { ret = handle_vanilla_tcp (&d[index]); } else if(enable_http && d[index].len >= 4 && strncmp((char *)d[index].buf, "GET ", 4) == 0 && strncmp((char *)d[index].buf + d[index].len - 4, "\r\n\r\n", 4) == 0) { ret = handle_http_tcp (&d[index]); if (ret < 0) clear_descr (d + index); } else if (d[index].len > 4) { kdc_log (0, "TCP data of strange type from %s", d[index].addr_string); return; } if (ret < 0) return; else if (ret == 1) { do_request(d[index].buf, d[index].len, 1, &d[index]); clear_descr(d + index); } } void loop(void) { struct descr *d; int ndescr; ndescr = init_sockets(&d); if(ndescr <= 0) krb5_errx(context, 1, "No sockets!"); while(exit_flag == 0){ struct timeval tmout; fd_set fds; int min_free = -1; int max_fd = 0; int i; FD_ZERO(&fds); for(i = 0; i < ndescr; i++) { if(d[i].s >= 0){ if(d[i].type == SOCK_STREAM && d[i].timeout && d[i].timeout < time(NULL)) { kdc_log(1, "TCP-connection from %s expired after %lu bytes", d[i].addr_string, (unsigned long)d[i].len); clear_descr(&d[i]); continue; } if(max_fd < d[i].s) max_fd = d[i].s; if (max_fd >= FD_SETSIZE) krb5_errx(context, 1, "fd too large"); FD_SET(d[i].s, &fds); } else if(min_free < 0 || i < min_free) min_free = i; } if(min_free == -1){ struct descr *tmp; tmp = realloc(d, (ndescr + 4) * sizeof(*d)); if(tmp == NULL) krb5_warnx(context, "No memory"); else { d = tmp; reinit_descrs (d, ndescr); memset(d + ndescr, 0, 4 * sizeof(*d)); for(i = ndescr; i < ndescr + 4; i++) init_descr (&d[i]); min_free = ndescr; ndescr += 4; } } tmout.tv_sec = TCP_TIMEOUT; tmout.tv_usec = 0; switch(select(max_fd + 1, &fds, 0, 0, &tmout)){ case 0: break; case -1: if (errno != EINTR) krb5_warn(context, errno, "select"); break; default: for(i = 0; i < ndescr; i++) if(d[i].s >= 0 && FD_ISSET(d[i].s, &fds)) { if(d[i].type == SOCK_DGRAM) handle_udp(&d[i]); else if(d[i].type == SOCK_STREAM) handle_tcp(d, i, min_free); } } } free (d); }