rexec.c 5.1 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. #define SA_LEN(_x) __libc_sa_len((_x)->sa_family)
  42. extern int __libc_sa_len(sa_family_t __af) __THROW attribute_hidden;
  43. /* int rexecoptions; - google does not know it */
  44. static char ahostbuf[NI_MAXHOST];
  45. int
  46. rexec_af(char **ahost, int rport, const char *name, const char *pass, const char *cmd, int *fd2p, sa_family_t af)
  47. {
  48. struct sockaddr_storage sa2, from;
  49. struct addrinfo hints, *res0;
  50. const char *orig_name = name;
  51. const char *orig_pass = pass;
  52. u_short port = 0;
  53. int s, timo = 1, s3;
  54. char c;
  55. int gai;
  56. char servbuff[NI_MAXSERV];
  57. if (sizeof(servbuff) < sizeof(int)*3 + 2) {
  58. snprintf(servbuff, sizeof(servbuff), "%d", ntohs(rport));
  59. servbuff[sizeof(servbuff) - 1] = '\0';
  60. } else {
  61. sprintf(servbuff, "%d", ntohs(rport));
  62. }
  63. memset(&hints, '\0', sizeof(hints));
  64. hints.ai_family = af;
  65. hints.ai_socktype = SOCK_STREAM;
  66. hints.ai_flags = AI_CANONNAME;
  67. gai = getaddrinfo(*ahost, servbuff, &hints, &res0);
  68. if (gai) {
  69. /* XXX: set errno? */
  70. return -1;
  71. }
  72. if (res0->ai_canonname) {
  73. strncpy(ahostbuf, res0->ai_canonname, sizeof(ahostbuf));
  74. ahostbuf[sizeof(ahostbuf)-1] = '\0';
  75. *ahost = ahostbuf;
  76. }
  77. else {
  78. *ahost = NULL;
  79. __set_errno(ENOENT);
  80. return -1;
  81. }
  82. ruserpass(res0->ai_canonname, &name, &pass);
  83. retry:
  84. s = socket(res0->ai_family, res0->ai_socktype, 0);
  85. if (s < 0) {
  86. perror("rexec: socket");
  87. return -1;
  88. }
  89. if (connect(s, res0->ai_addr, res0->ai_addrlen) < 0) {
  90. if (errno == ECONNREFUSED && timo <= 16) {
  91. (void) close(s);
  92. sleep(timo);
  93. timo *= 2;
  94. goto retry;
  95. }
  96. perror(res0->ai_canonname);
  97. return -1;
  98. }
  99. if (fd2p == 0) {
  100. (void) write(s, "", 1);
  101. port = 0;
  102. } else {
  103. char num[32];
  104. int s2;
  105. socklen_t sa2len;
  106. s2 = socket(res0->ai_family, res0->ai_socktype, 0);
  107. if (s2 < 0) {
  108. (void) close(s);
  109. return -1;
  110. }
  111. listen(s2, 1);
  112. sa2len = sizeof(sa2);
  113. if (getsockname(s2, (struct sockaddr *)&sa2, &sa2len) < 0) {
  114. perror("getsockname");
  115. (void) close(s2);
  116. goto bad;
  117. } else if (sa2len != SA_LEN((struct sockaddr *)&sa2)) {
  118. __set_errno(EINVAL);
  119. (void) close(s2);
  120. goto bad;
  121. }
  122. port = 0;
  123. if (!getnameinfo((struct sockaddr *)&sa2, sa2len,
  124. NULL, 0, servbuff, sizeof(servbuff),
  125. NI_NUMERICSERV))
  126. port = atoi(servbuff);
  127. (void) sprintf(num, "%u", port);
  128. (void) write(s, num, strlen(num)+1);
  129. {
  130. socklen_t len = sizeof(from);
  131. s3 = TEMP_FAILURE_RETRY(accept(s2,
  132. (struct sockaddr *)&from, &len));
  133. close(s2);
  134. if (s3 < 0) {
  135. perror("accept");
  136. port = 0;
  137. goto bad;
  138. }
  139. }
  140. *fd2p = s3;
  141. }
  142. (void) write(s, name, strlen(name) + 1);
  143. /* should public key encypt the password here */
  144. (void) write(s, pass, strlen(pass) + 1);
  145. (void) write(s, cmd, strlen(cmd) + 1);
  146. /* We don't need the memory allocated for the name and the password
  147. in ruserpass anymore. */
  148. if (name != orig_name)
  149. free((char *) name);
  150. if (pass != orig_pass)
  151. free((char *) pass);
  152. if (read(s, &c, 1) != 1) {
  153. perror(*ahost);
  154. goto bad;
  155. }
  156. if (c != 0) {
  157. while (read(s, &c, 1) == 1) {
  158. (void) write(2, &c, 1);
  159. if (c == '\n')
  160. break;
  161. }
  162. goto bad;
  163. }
  164. freeaddrinfo(res0);
  165. return s;
  166. bad:
  167. if (port)
  168. (void) close(*fd2p);
  169. (void) close(s);
  170. freeaddrinfo(res0);
  171. return -1;
  172. }
  173. libc_hidden_def(rexec_af)
  174. int
  175. rexec(char **ahost, int rport, const char *name, const char *pass,
  176. const char *cmd, int *fd2p)
  177. {
  178. return rexec_af(ahost, rport, name, pass, cmd, fd2p, AF_INET);
  179. }