rexec.c 5.6 KB

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  1. /*
  2. * Copyright (c) 1980, 1993
  3. * The Regents of the University of California. All rights reserved.
  4. *
  5. * Redistribution and use in source and binary forms, with or without
  6. * modification, are permitted provided that the following conditions
  7. * are met:
  8. * 1. Redistributions of source code must retain the above copyright
  9. * notice, this list of conditions and the following disclaimer.
  10. * 2. Redistributions in binary form must reproduce the above copyright
  11. * notice, this list of conditions and the following disclaimer in the
  12. * documentation and/or other materials provided with the distribution.
  13. * 4. Neither the name of the University nor the names of its contributors
  14. * may be used to endorse or promote products derived from this software
  15. * without specific prior written permission.
  16. *
  17. * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18. * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19. * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20. * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21. * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22. * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23. * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24. * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25. * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26. * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27. * SUCH DAMAGE.
  28. */
  29. #define __FORCE_GLIBC
  30. #include <features.h>
  31. #include <sys/types.h>
  32. #include <sys/socket.h>
  33. #include <netinet/in.h>
  34. #include <alloca.h>
  35. #include <stdio.h>
  36. #include <netdb.h>
  37. #include <errno.h>
  38. #include <stdlib.h>
  39. #include <string.h>
  40. #include <unistd.h>
  41. libc_hidden_proto(memset)
  42. libc_hidden_proto(strlen)
  43. libc_hidden_proto(strncpy)
  44. libc_hidden_proto(read)
  45. libc_hidden_proto(write)
  46. libc_hidden_proto(close)
  47. libc_hidden_proto(socket)
  48. libc_hidden_proto(perror)
  49. libc_hidden_proto(sprintf)
  50. libc_hidden_proto(snprintf)
  51. libc_hidden_proto(getsockname)
  52. libc_hidden_proto(getnameinfo)
  53. libc_hidden_proto(getaddrinfo)
  54. libc_hidden_proto(freeaddrinfo)
  55. libc_hidden_proto(sleep)
  56. libc_hidden_proto(atoi)
  57. libc_hidden_proto(connect)
  58. libc_hidden_proto(accept)
  59. libc_hidden_proto(listen)
  60. #define SA_LEN(_x) __libc_sa_len((_x)->sa_family)
  61. extern int __libc_sa_len (sa_family_t __af) __THROW attribute_hidden;
  62. int rexecoptions;
  63. char ahostbuf[NI_MAXHOST] attribute_hidden;
  64. extern int ruserpass(const char *host, const char **aname, const char **apass) attribute_hidden;
  65. libc_hidden_proto(ruserpass)
  66. libc_hidden_proto(rexec_af)
  67. int
  68. rexec_af(char **ahost, int rport, const char *name, const char *pass, const char *cmd, int *fd2p, sa_family_t af)
  69. {
  70. struct sockaddr_storage sa2, from;
  71. struct addrinfo hints, *res0;
  72. const char *orig_name = name;
  73. const char *orig_pass = pass;
  74. u_short port = 0;
  75. int s, timo = 1, s3;
  76. char c;
  77. int gai;
  78. char servbuff[NI_MAXSERV];
  79. snprintf(servbuff, sizeof(servbuff), "%d", ntohs(rport));
  80. servbuff[sizeof(servbuff) - 1] = '\0';
  81. memset(&hints, 0, sizeof(hints));
  82. hints.ai_family = af;
  83. hints.ai_socktype = SOCK_STREAM;
  84. hints.ai_flags = AI_CANONNAME;
  85. gai = getaddrinfo(*ahost, servbuff, &hints, &res0);
  86. if (gai){
  87. /* XXX: set errno? */
  88. return -1;
  89. }
  90. if (res0->ai_canonname){
  91. strncpy(ahostbuf, res0->ai_canonname, sizeof(ahostbuf));
  92. ahostbuf[sizeof(ahostbuf)-1] = '\0';
  93. *ahost = ahostbuf;
  94. }
  95. else{
  96. *ahost = NULL;
  97. }
  98. ruserpass(res0->ai_canonname, &name, &pass);
  99. retry:
  100. s = socket(res0->ai_family, res0->ai_socktype, 0);
  101. if (s < 0) {
  102. perror("rexec: socket");
  103. return (-1);
  104. }
  105. if (connect(s, res0->ai_addr, res0->ai_addrlen) < 0) {
  106. if (errno == ECONNREFUSED && timo <= 16) {
  107. (void) close(s);
  108. sleep(timo);
  109. timo *= 2;
  110. goto retry;
  111. }
  112. perror(res0->ai_canonname);
  113. return (-1);
  114. }
  115. if (fd2p == 0) {
  116. (void) write(s, "", 1);
  117. port = 0;
  118. } else {
  119. char num[32];
  120. int s2, sa2len;
  121. s2 = socket(res0->ai_family, res0->ai_socktype, 0);
  122. if (s2 < 0) {
  123. (void) close(s);
  124. return (-1);
  125. }
  126. listen(s2, 1);
  127. sa2len = sizeof (sa2);
  128. if (getsockname(s2, (struct sockaddr *)&sa2, &sa2len) < 0) {
  129. perror("getsockname");
  130. (void) close(s2);
  131. goto bad;
  132. } else if (sa2len != SA_LEN((struct sockaddr *)&sa2)) {
  133. __set_errno(EINVAL);
  134. (void) close(s2);
  135. goto bad;
  136. }
  137. port = 0;
  138. if (!getnameinfo((struct sockaddr *)&sa2, sa2len,
  139. NULL, 0, servbuff, sizeof(servbuff),
  140. NI_NUMERICSERV))
  141. port = atoi(servbuff);
  142. (void) sprintf(num, "%u", port);
  143. (void) write(s, num, strlen(num)+1);
  144. { socklen_t len = sizeof (from);
  145. s3 = accept(s2, (struct sockaddr *)&from, &len);
  146. close(s2);
  147. if (s3 < 0) {
  148. perror("accept");
  149. port = 0;
  150. goto bad;
  151. }
  152. }
  153. *fd2p = s3;
  154. }
  155. (void) write(s, name, strlen(name) + 1);
  156. /* should public key encypt the password here */
  157. (void) write(s, pass, strlen(pass) + 1);
  158. (void) write(s, cmd, strlen(cmd) + 1);
  159. /* We don't need the memory allocated for the name and the password
  160. in ruserpass anymore. */
  161. if (name != orig_name)
  162. free ((char *) name);
  163. if (pass != orig_pass)
  164. free ((char *) pass);
  165. if (read(s, &c, 1) != 1) {
  166. perror(*ahost);
  167. goto bad;
  168. }
  169. if (c != 0) {
  170. while (read(s, &c, 1) == 1) {
  171. (void) write(2, &c, 1);
  172. if (c == '\n')
  173. break;
  174. }
  175. goto bad;
  176. }
  177. freeaddrinfo(res0);
  178. return (s);
  179. bad:
  180. if (port)
  181. (void) close(*fd2p);
  182. (void) close(s);
  183. freeaddrinfo(res0);
  184. return (-1);
  185. }
  186. libc_hidden_def(rexec_af)
  187. int
  188. rexec(ahost, rport, name, pass, cmd, fd2p)
  189. char **ahost;
  190. int rport;
  191. const char *name, *pass, *cmd;
  192. int *fd2p;
  193. {
  194. return rexec_af(ahost, rport, name, pass, cmd, fd2p, AF_INET);
  195. }