1 /*- 2 * Copyright (c) 2015-2017 Dag-Erling Smørgrav 3 * 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 * 3. The name of the author may not be used to endorse or promote 14 * products derived from this software without specific prior written 15 * permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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 * $OpenPAM: t_pam_conv.c 938 2017-04-30 21:34:42Z des $ 30 */ 31 32 #ifdef HAVE_CONFIG_H 33 # include "config.h" 34 #endif 35 36 #include <err.h> 37 #include <errno.h> 38 #include <stdint.h> 39 #include <stdio.h> 40 #include <stdlib.h> 41 #include <string.h> 42 43 #include <cryb/test.h> 44 45 #include <security/pam_appl.h> 46 #include <security/openpam.h> 47 48 #include "openpam_impl.h" 49 #include "openpam_asprintf.h" 50 51 #include "t_pam_conv.h" 52 53 /* 54 * Conversation function 55 * 56 * The appdata argument points to a struct t_pam_conv_script which 57 * contains both the expected messages and the desired responses. If 58 * script.responses is NULL, t_pam_conv() will return PAM_CONV_ERR. If an 59 * error occurs (incorrect number of messages, messages don't match script 60 * etc.), script.comment will be set to point to a malloc()ed string 61 * describing the error. Otherwise, t_pam_conv() will return to its 62 * caller a malloc()ed copy of script.responses. 63 */ 64 int 65 t_pam_conv(int nm, const struct pam_message **msgs, 66 struct pam_response **respsp, void *ad) 67 { 68 struct t_pam_conv_script *s = ad; 69 struct pam_response *resps; 70 int i; 71 72 /* check message count */ 73 if (nm != s->nmsg) { 74 asprintf(&s->comment, "expected %d messages, got %d", 75 s->nmsg, nm); 76 return (PAM_CONV_ERR); 77 } 78 if (nm <= 0 || nm > PAM_MAX_NUM_MSG) { 79 /* since the previous test passed, this is intentional! */ 80 s->comment = NULL; 81 return (PAM_CONV_ERR); 82 } 83 84 /* check each message and provide the sed answer */ 85 if ((resps = calloc(nm, sizeof *resps)) == NULL) 86 goto enomem; 87 for (i = 0; i < nm; ++i) { 88 if (msgs[i]->msg_style != s->msgs[i].msg_style) { 89 asprintf(&s->comment, 90 "message %d expected style %d got %d", i, 91 s->msgs[i].msg_style, msgs[i]->msg_style); 92 goto fail; 93 } 94 if (strcmp(msgs[i]->msg, s->msgs[i].msg) != 0) { 95 asprintf(&s->comment, 96 "message %d expected \"%s\" got \"%s\"", i, 97 s->msgs[i].msg, msgs[i]->msg); 98 goto fail; 99 } 100 switch (msgs[i]->msg_style) { 101 case PAM_PROMPT_ECHO_OFF: 102 t_printv("[PAM_PROMPT_ECHO_OFF] %s\n", msgs[i]->msg); 103 break; 104 case PAM_PROMPT_ECHO_ON: 105 t_printv("[PAM_PROMPT_ECHO_ON] %s\n", msgs[i]->msg); 106 break; 107 case PAM_ERROR_MSG: 108 t_printv("[PAM_ERROR_MSG] %s\n", msgs[i]->msg); 109 break; 110 case PAM_TEXT_INFO: 111 t_printv("[PAM_TEXT_INFO] %s\n", msgs[i]->msg); 112 break; 113 default: 114 asprintf(&s->comment, "invalid message style %d", 115 msgs[i]->msg_style); 116 goto fail; 117 } 118 /* copy the response, if there is one */ 119 if (s->resps[i].resp != NULL && 120 (resps[i].resp = strdup(s->resps[i].resp)) == NULL) 121 goto enomem; 122 resps[i].resp_retcode = s->resps[i].resp_retcode; 123 } 124 s->comment = NULL; 125 *respsp = resps; 126 return (PAM_SUCCESS); 127 enomem: 128 asprintf(&s->comment, "%s", strerror(ENOMEM)); 129 fail: 130 for (i = 0; i < nm; ++i) 131 free(resps[i].resp); 132 free(resps); 133 return (PAM_CONV_ERR); 134 } 135