1 | /* |
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2 | * Author: Tatu Ylonen <ylo@cs.hut.fi> |
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3 | * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland |
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4 | * All rights reserved |
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5 | * This file contains functions for reading and writing identity files, and |
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6 | * for reading the passphrase from the user. |
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7 | * |
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8 | * As far as I am concerned, the code I have written for this software |
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9 | * can be used freely for any purpose. Any derived versions of this |
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10 | * software must be clearly marked as such, and if the derived work is |
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11 | * incompatible with the protocol description in the RFC file, it must be |
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12 | * called by a name other than "ssh" or "Secure Shell". |
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13 | * |
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14 | * |
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15 | * Copyright (c) 2000 Markus Friedl. All rights reserved. |
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16 | * |
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17 | * Redistribution and use in source and binary forms, with or without |
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18 | * modification, are permitted provided that the following conditions |
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19 | * are met: |
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20 | * 1. Redistributions of source code must retain the above copyright |
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21 | * notice, this list of conditions and the following disclaimer. |
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22 | * 2. Redistributions in binary form must reproduce the above copyright |
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23 | * notice, this list of conditions and the following disclaimer in the |
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24 | * documentation and/or other materials provided with the distribution. |
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25 | * |
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26 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
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27 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
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28 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
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29 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
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30 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
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31 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
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32 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
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33 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
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34 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
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35 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
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36 | */ |
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37 | |
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38 | #include "includes.h" |
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39 | RCSID("$OpenBSD: authfile.c,v 1.39 2001/10/07 10:29:52 markus Exp $"); |
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40 | |
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41 | #include <openssl/err.h> |
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42 | #include <openssl/evp.h> |
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43 | #include <openssl/pem.h> |
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44 | |
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45 | #include "cipher.h" |
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46 | #include "xmalloc.h" |
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47 | #include "buffer.h" |
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48 | #include "bufaux.h" |
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49 | #include "key.h" |
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50 | #include "ssh.h" |
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51 | #include "log.h" |
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52 | #include "authfile.h" |
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53 | |
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54 | /* Version identification string for SSH v1 identity files. */ |
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55 | static const char authfile_id_string[] = |
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56 | "SSH PRIVATE KEY FILE FORMAT 1.1\n"; |
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57 | |
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58 | /* |
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59 | * Saves the authentication (private) key in a file, encrypting it with |
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60 | * passphrase. The identification of the file (lowest 64 bits of n) will |
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61 | * precede the key to provide identification of the key without needing a |
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62 | * passphrase. |
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63 | */ |
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64 | |
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65 | static int |
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66 | key_save_private_rsa1(Key *key, const char *filename, const char *passphrase, |
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67 | const char *comment) |
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68 | { |
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69 | Buffer buffer, encrypted; |
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70 | char buf[100], *cp; |
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71 | int fd, i; |
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72 | CipherContext ciphercontext; |
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73 | Cipher *cipher; |
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74 | u_int32_t rand; |
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75 | |
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76 | /* |
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77 | * If the passphrase is empty, use SSH_CIPHER_NONE to ease converting |
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78 | * to another cipher; otherwise use SSH_AUTHFILE_CIPHER. |
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79 | */ |
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80 | if (strcmp(passphrase, "") == 0) |
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81 | cipher = cipher_by_number(SSH_CIPHER_NONE); |
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82 | else |
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83 | cipher = cipher_by_number(SSH_AUTHFILE_CIPHER); |
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84 | if (cipher == NULL) |
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85 | fatal("save_private_key_rsa: bad cipher"); |
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86 | |
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87 | /* This buffer is used to built the secret part of the private key. */ |
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88 | buffer_init(&buffer); |
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89 | |
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90 | /* Put checkbytes for checking passphrase validity. */ |
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91 | rand = arc4random(); |
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92 | buf[0] = rand & 0xff; |
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93 | buf[1] = (rand >> 8) & 0xff; |
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94 | buf[2] = buf[0]; |
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95 | buf[3] = buf[1]; |
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96 | buffer_append(&buffer, buf, 4); |
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97 | |
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98 | /* |
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99 | * Store the private key (n and e will not be stored because they |
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100 | * will be stored in plain text, and storing them also in encrypted |
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101 | * format would just give known plaintext). |
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102 | */ |
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103 | buffer_put_bignum(&buffer, key->rsa->d); |
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104 | buffer_put_bignum(&buffer, key->rsa->iqmp); |
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105 | buffer_put_bignum(&buffer, key->rsa->q); /* reverse from SSL p */ |
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106 | buffer_put_bignum(&buffer, key->rsa->p); /* reverse from SSL q */ |
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107 | |
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108 | /* Pad the part to be encrypted until its size is a multiple of 8. */ |
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109 | while (buffer_len(&buffer) % 8 != 0) |
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110 | buffer_put_char(&buffer, 0); |
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111 | |
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112 | /* This buffer will be used to contain the data in the file. */ |
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113 | buffer_init(&encrypted); |
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114 | |
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115 | /* First store keyfile id string. */ |
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116 | for (i = 0; authfile_id_string[i]; i++) |
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117 | buffer_put_char(&encrypted, authfile_id_string[i]); |
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118 | buffer_put_char(&encrypted, 0); |
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119 | |
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120 | /* Store cipher type. */ |
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121 | buffer_put_char(&encrypted, cipher->number); |
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122 | buffer_put_int(&encrypted, 0); /* For future extension */ |
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123 | |
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124 | /* Store public key. This will be in plain text. */ |
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125 | buffer_put_int(&encrypted, BN_num_bits(key->rsa->n)); |
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126 | buffer_put_bignum(&encrypted, key->rsa->n); |
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127 | buffer_put_bignum(&encrypted, key->rsa->e); |
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128 | buffer_put_cstring(&encrypted, comment); |
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129 | |
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130 | /* Allocate space for the private part of the key in the buffer. */ |
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131 | buffer_append_space(&encrypted, &cp, buffer_len(&buffer)); |
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132 | |
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133 | cipher_set_key_string(&ciphercontext, cipher, passphrase); |
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134 | cipher_encrypt(&ciphercontext, (u_char *) cp, |
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135 | (u_char *) buffer_ptr(&buffer), buffer_len(&buffer)); |
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136 | memset(&ciphercontext, 0, sizeof(ciphercontext)); |
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137 | |
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138 | /* Destroy temporary data. */ |
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139 | memset(buf, 0, sizeof(buf)); |
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140 | buffer_free(&buffer); |
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141 | |
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142 | fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0600); |
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143 | if (fd < 0) { |
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144 | error("open %s failed: %s.", filename, strerror(errno)); |
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145 | return 0; |
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146 | } |
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147 | if (write(fd, buffer_ptr(&encrypted), buffer_len(&encrypted)) != |
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148 | buffer_len(&encrypted)) { |
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149 | error("write to key file %s failed: %s", filename, |
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150 | strerror(errno)); |
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151 | buffer_free(&encrypted); |
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152 | close(fd); |
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153 | unlink(filename); |
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154 | return 0; |
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155 | } |
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156 | close(fd); |
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157 | buffer_free(&encrypted); |
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158 | return 1; |
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159 | } |
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160 | |
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161 | /* save SSH v2 key in OpenSSL PEM format */ |
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162 | static int |
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163 | key_save_private_pem(Key *key, const char *filename, const char *_passphrase, |
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164 | const char *comment) |
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165 | { |
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166 | FILE *fp; |
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167 | int fd; |
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168 | int success = 0; |
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169 | int len = strlen(_passphrase); |
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170 | char *passphrase = (len > 0) ? (char *)_passphrase : NULL; |
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171 | EVP_CIPHER *cipher = (len > 0) ? EVP_des_ede3_cbc() : NULL; |
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172 | |
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173 | if (len > 0 && len <= 4) { |
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174 | error("passphrase too short: have %d bytes, need > 4", len); |
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175 | return 0; |
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176 | } |
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177 | fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0600); |
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178 | if (fd < 0) { |
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179 | error("open %s failed: %s.", filename, strerror(errno)); |
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180 | return 0; |
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181 | } |
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182 | fp = fdopen(fd, "w"); |
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183 | if (fp == NULL ) { |
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184 | error("fdopen %s failed: %s.", filename, strerror(errno)); |
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185 | close(fd); |
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186 | return 0; |
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187 | } |
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188 | switch (key->type) { |
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189 | case KEY_DSA: |
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190 | success = PEM_write_DSAPrivateKey(fp, key->dsa, |
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191 | cipher, passphrase, len, NULL, NULL); |
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192 | break; |
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193 | case KEY_RSA: |
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194 | success = PEM_write_RSAPrivateKey(fp, key->rsa, |
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195 | cipher, passphrase, len, NULL, NULL); |
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196 | break; |
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197 | } |
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198 | fclose(fp); |
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199 | return success; |
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200 | } |
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201 | |
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202 | int |
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203 | key_save_private(Key *key, const char *filename, const char *passphrase, |
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204 | const char *comment) |
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205 | { |
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206 | switch (key->type) { |
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207 | case KEY_RSA1: |
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208 | return key_save_private_rsa1(key, filename, passphrase, |
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209 | comment); |
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210 | break; |
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211 | case KEY_DSA: |
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212 | case KEY_RSA: |
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213 | return key_save_private_pem(key, filename, passphrase, |
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214 | comment); |
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215 | break; |
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216 | default: |
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217 | break; |
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218 | } |
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219 | error("key_save_private: cannot save key type %d", key->type); |
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220 | return 0; |
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221 | } |
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222 | |
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223 | /* |
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224 | * Loads the public part of the ssh v1 key file. Returns NULL if an error was |
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225 | * encountered (the file does not exist or is not readable), and the key |
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226 | * otherwise. |
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227 | */ |
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228 | |
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229 | static Key * |
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230 | key_load_public_rsa1(int fd, const char *filename, char **commentp) |
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231 | { |
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232 | Buffer buffer; |
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233 | Key *pub; |
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234 | char *cp; |
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235 | int i; |
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236 | off_t len; |
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237 | |
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238 | len = lseek(fd, (off_t) 0, SEEK_END); |
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239 | lseek(fd, (off_t) 0, SEEK_SET); |
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240 | |
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241 | buffer_init(&buffer); |
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242 | buffer_append_space(&buffer, &cp, len); |
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243 | |
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244 | if (read(fd, cp, (size_t) len) != (size_t) len) { |
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245 | debug("Read from key file %.200s failed: %.100s", filename, |
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246 | strerror(errno)); |
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247 | buffer_free(&buffer); |
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248 | return NULL; |
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249 | } |
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250 | |
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251 | /* Check that it is at least big enough to contain the ID string. */ |
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252 | if (len < sizeof(authfile_id_string)) { |
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253 | debug3("Not a RSA1 key file %.200s.", filename); |
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254 | buffer_free(&buffer); |
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255 | return NULL; |
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256 | } |
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257 | /* |
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258 | * Make sure it begins with the id string. Consume the id string |
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259 | * from the buffer. |
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260 | */ |
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261 | for (i = 0; i < sizeof(authfile_id_string); i++) |
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262 | if (buffer_get_char(&buffer) != authfile_id_string[i]) { |
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263 | debug3("Not a RSA1 key file %.200s.", filename); |
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264 | buffer_free(&buffer); |
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265 | return NULL; |
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266 | } |
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267 | /* Skip cipher type and reserved data. */ |
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268 | (void) buffer_get_char(&buffer); /* cipher type */ |
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269 | (void) buffer_get_int(&buffer); /* reserved */ |
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270 | |
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271 | /* Read the public key from the buffer. */ |
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272 | buffer_get_int(&buffer); |
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273 | pub = key_new(KEY_RSA1); |
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274 | buffer_get_bignum(&buffer, pub->rsa->n); |
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275 | buffer_get_bignum(&buffer, pub->rsa->e); |
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276 | if (commentp) |
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277 | *commentp = buffer_get_string(&buffer, NULL); |
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278 | /* The encrypted private part is not parsed by this function. */ |
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279 | |
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280 | buffer_free(&buffer); |
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281 | return pub; |
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282 | } |
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283 | |
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284 | /* load public key from private-key file, works only for SSH v1 */ |
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285 | Key * |
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286 | key_load_public_type(int type, const char *filename, char **commentp) |
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287 | { |
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288 | Key *pub; |
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289 | int fd; |
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290 | |
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291 | if (type == KEY_RSA1) { |
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292 | fd = open(filename, O_RDONLY); |
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293 | if (fd < 0) |
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294 | return NULL; |
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295 | pub = key_load_public_rsa1(fd, filename, commentp); |
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296 | close(fd); |
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297 | return pub; |
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298 | } |
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299 | return NULL; |
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300 | } |
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301 | |
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302 | /* |
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303 | * Loads the private key from the file. Returns 0 if an error is encountered |
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304 | * (file does not exist or is not readable, or passphrase is bad). This |
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305 | * initializes the private key. |
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306 | * Assumes we are called under uid of the owner of the file. |
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307 | */ |
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308 | |
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309 | static Key * |
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310 | key_load_private_rsa1(int fd, const char *filename, const char *passphrase, |
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311 | char **commentp) |
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312 | { |
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313 | int i, check1, check2, cipher_type; |
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314 | off_t len; |
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315 | Buffer buffer, decrypted; |
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316 | char *cp; |
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317 | CipherContext ciphercontext; |
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318 | Cipher *cipher; |
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319 | BN_CTX *ctx; |
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320 | BIGNUM *aux; |
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321 | Key *prv = NULL; |
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322 | |
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323 | len = lseek(fd, (off_t) 0, SEEK_END); |
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324 | lseek(fd, (off_t) 0, SEEK_SET); |
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325 | |
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326 | buffer_init(&buffer); |
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327 | buffer_append_space(&buffer, &cp, len); |
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328 | |
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329 | if (read(fd, cp, (size_t) len) != (size_t) len) { |
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330 | debug("Read from key file %.200s failed: %.100s", filename, |
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331 | strerror(errno)); |
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332 | buffer_free(&buffer); |
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333 | close(fd); |
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334 | return NULL; |
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335 | } |
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336 | |
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337 | /* Check that it is at least big enough to contain the ID string. */ |
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338 | if (len < sizeof(authfile_id_string)) { |
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339 | debug3("Not a RSA1 key file %.200s.", filename); |
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340 | buffer_free(&buffer); |
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341 | close(fd); |
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342 | return NULL; |
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343 | } |
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344 | /* |
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345 | * Make sure it begins with the id string. Consume the id string |
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346 | * from the buffer. |
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347 | */ |
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348 | for (i = 0; i < sizeof(authfile_id_string); i++) |
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349 | if (buffer_get_char(&buffer) != authfile_id_string[i]) { |
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350 | debug3("Not a RSA1 key file %.200s.", filename); |
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351 | buffer_free(&buffer); |
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352 | close(fd); |
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353 | return NULL; |
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354 | } |
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355 | |
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356 | /* Read cipher type. */ |
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357 | cipher_type = buffer_get_char(&buffer); |
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358 | (void) buffer_get_int(&buffer); /* Reserved data. */ |
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359 | |
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360 | /* Read the public key from the buffer. */ |
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361 | buffer_get_int(&buffer); |
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362 | prv = key_new_private(KEY_RSA1); |
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363 | |
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364 | buffer_get_bignum(&buffer, prv->rsa->n); |
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365 | buffer_get_bignum(&buffer, prv->rsa->e); |
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366 | if (commentp) |
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367 | *commentp = buffer_get_string(&buffer, NULL); |
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368 | else |
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369 | xfree(buffer_get_string(&buffer, NULL)); |
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370 | |
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371 | /* Check that it is a supported cipher. */ |
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372 | cipher = cipher_by_number(cipher_type); |
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373 | if (cipher == NULL) { |
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374 | debug("Unsupported cipher %d used in key file %.200s.", |
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375 | cipher_type, filename); |
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376 | buffer_free(&buffer); |
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377 | goto fail; |
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378 | } |
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379 | /* Initialize space for decrypted data. */ |
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380 | buffer_init(&decrypted); |
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381 | buffer_append_space(&decrypted, &cp, buffer_len(&buffer)); |
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382 | |
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383 | /* Rest of the buffer is encrypted. Decrypt it using the passphrase. */ |
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384 | cipher_set_key_string(&ciphercontext, cipher, passphrase); |
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385 | cipher_decrypt(&ciphercontext, (u_char *) cp, |
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386 | (u_char *) buffer_ptr(&buffer), buffer_len(&buffer)); |
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387 | memset(&ciphercontext, 0, sizeof(ciphercontext)); |
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388 | buffer_free(&buffer); |
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389 | |
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390 | check1 = buffer_get_char(&decrypted); |
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391 | check2 = buffer_get_char(&decrypted); |
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392 | if (check1 != buffer_get_char(&decrypted) || |
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393 | check2 != buffer_get_char(&decrypted)) { |
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394 | if (strcmp(passphrase, "") != 0) |
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395 | debug("Bad passphrase supplied for key file %.200s.", |
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396 | filename); |
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397 | /* Bad passphrase. */ |
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398 | buffer_free(&decrypted); |
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399 | goto fail; |
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400 | } |
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401 | /* Read the rest of the private key. */ |
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402 | buffer_get_bignum(&decrypted, prv->rsa->d); |
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403 | buffer_get_bignum(&decrypted, prv->rsa->iqmp); /* u */ |
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404 | /* in SSL and SSH v1 p and q are exchanged */ |
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405 | buffer_get_bignum(&decrypted, prv->rsa->q); /* p */ |
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406 | buffer_get_bignum(&decrypted, prv->rsa->p); /* q */ |
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407 | |
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408 | /* calculate p-1 and q-1 */ |
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409 | ctx = BN_CTX_new(); |
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410 | aux = BN_new(); |
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411 | |
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412 | BN_sub(aux, prv->rsa->q, BN_value_one()); |
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413 | BN_mod(prv->rsa->dmq1, prv->rsa->d, aux, ctx); |
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414 | |
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415 | BN_sub(aux, prv->rsa->p, BN_value_one()); |
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416 | BN_mod(prv->rsa->dmp1, prv->rsa->d, aux, ctx); |
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417 | |
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418 | BN_clear_free(aux); |
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419 | BN_CTX_free(ctx); |
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420 | |
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421 | buffer_free(&decrypted); |
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422 | close(fd); |
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423 | return prv; |
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424 | |
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425 | fail: |
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426 | if (commentp) |
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427 | xfree(*commentp); |
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428 | close(fd); |
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429 | key_free(prv); |
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430 | return NULL; |
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431 | } |
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432 | |
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433 | static Key * |
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434 | key_load_private_pem(int fd, int type, const char *passphrase, |
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435 | char **commentp) |
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436 | { |
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437 | FILE *fp; |
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438 | EVP_PKEY *pk = NULL; |
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439 | Key *prv = NULL; |
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440 | char *name = "<no key>"; |
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441 | |
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442 | fp = fdopen(fd, "r"); |
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443 | if (fp == NULL) { |
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444 | error("fdopen failed: %s", strerror(errno)); |
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445 | close(fd); |
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446 | return NULL; |
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447 | } |
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448 | pk = PEM_read_PrivateKey(fp, NULL, NULL, (char *)passphrase); |
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449 | if (pk == NULL) { |
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450 | debug("PEM_read_PrivateKey failed"); |
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451 | (void)ERR_get_error(); |
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452 | } else if (pk->type == EVP_PKEY_RSA && |
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453 | (type == KEY_UNSPEC||type==KEY_RSA)) { |
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454 | prv = key_new(KEY_UNSPEC); |
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455 | prv->rsa = EVP_PKEY_get1_RSA(pk); |
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456 | prv->type = KEY_RSA; |
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457 | name = "rsa w/o comment"; |
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458 | #ifdef DEBUG_PK |
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459 | RSA_print_fp(stderr, prv->rsa, 8); |
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460 | #endif |
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461 | } else if (pk->type == EVP_PKEY_DSA && |
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462 | (type == KEY_UNSPEC||type==KEY_DSA)) { |
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463 | prv = key_new(KEY_UNSPEC); |
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464 | prv->dsa = EVP_PKEY_get1_DSA(pk); |
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465 | prv->type = KEY_DSA; |
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466 | name = "dsa w/o comment"; |
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467 | #ifdef DEBUG_PK |
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468 | DSA_print_fp(stderr, prv->dsa, 8); |
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469 | #endif |
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470 | } else { |
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471 | error("PEM_read_PrivateKey: mismatch or " |
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472 | "unknown EVP_PKEY save_type %d", pk->save_type); |
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473 | } |
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474 | fclose(fp); |
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475 | if (pk != NULL) |
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476 | EVP_PKEY_free(pk); |
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477 | if (prv != NULL && commentp) |
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478 | *commentp = xstrdup(name); |
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479 | debug("read PEM private key done: type %s", |
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480 | prv ? key_type(prv) : "<unknown>"); |
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481 | return prv; |
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482 | } |
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483 | |
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484 | static int |
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485 | key_perm_ok(int fd, const char *filename) |
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486 | { |
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487 | struct stat st; |
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488 | |
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489 | if (fstat(fd, &st) < 0) |
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490 | return 0; |
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491 | /* |
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492 | * if a key owned by the user is accessed, then we check the |
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493 | * permissions of the file. if the key owned by a different user, |
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494 | * then we don't care. |
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495 | */ |
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496 | #ifdef HAVE_CYGWIN |
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497 | if (check_ntsec(filename)) |
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498 | #endif |
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499 | if ((st.st_uid == getuid()) && (st.st_mode & 077) != 0) { |
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500 | error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"); |
---|
501 | error("@ WARNING: UNPROTECTED PRIVATE KEY FILE! @"); |
---|
502 | error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"); |
---|
503 | error("Permissions 0%3.3o for '%s' are too open.", |
---|
504 | st.st_mode & 0777, filename); |
---|
505 | error("It is recommended that your private key files are NOT accessible by others."); |
---|
506 | error("This private key will be ignored."); |
---|
507 | return 0; |
---|
508 | } |
---|
509 | return 1; |
---|
510 | } |
---|
511 | |
---|
512 | Key * |
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513 | key_load_private_type(int type, const char *filename, const char *passphrase, |
---|
514 | char **commentp) |
---|
515 | { |
---|
516 | int fd; |
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517 | |
---|
518 | fd = open(filename, O_RDONLY); |
---|
519 | if (fd < 0) |
---|
520 | return NULL; |
---|
521 | if (!key_perm_ok(fd, filename)) { |
---|
522 | error("bad permissions: ignore key: %s", filename); |
---|
523 | close(fd); |
---|
524 | return NULL; |
---|
525 | } |
---|
526 | switch (type) { |
---|
527 | case KEY_RSA1: |
---|
528 | return key_load_private_rsa1(fd, filename, passphrase, |
---|
529 | commentp); |
---|
530 | /* closes fd */ |
---|
531 | break; |
---|
532 | case KEY_DSA: |
---|
533 | case KEY_RSA: |
---|
534 | case KEY_UNSPEC: |
---|
535 | return key_load_private_pem(fd, type, passphrase, commentp); |
---|
536 | /* closes fd */ |
---|
537 | break; |
---|
538 | default: |
---|
539 | close(fd); |
---|
540 | break; |
---|
541 | } |
---|
542 | return NULL; |
---|
543 | } |
---|
544 | |
---|
545 | Key * |
---|
546 | key_load_private(const char *filename, const char *passphrase, |
---|
547 | char **commentp) |
---|
548 | { |
---|
549 | Key *pub, *prv; |
---|
550 | int fd; |
---|
551 | |
---|
552 | fd = open(filename, O_RDONLY); |
---|
553 | if (fd < 0) |
---|
554 | return NULL; |
---|
555 | if (!key_perm_ok(fd, filename)) { |
---|
556 | error("bad permissions: ignore key: %s", filename); |
---|
557 | close(fd); |
---|
558 | return NULL; |
---|
559 | } |
---|
560 | pub = key_load_public_rsa1(fd, filename, commentp); |
---|
561 | lseek(fd, (off_t) 0, SEEK_SET); /* rewind */ |
---|
562 | if (pub == NULL) { |
---|
563 | /* closes fd */ |
---|
564 | prv = key_load_private_pem(fd, KEY_UNSPEC, passphrase, NULL); |
---|
565 | /* use the filename as a comment for PEM */ |
---|
566 | if (commentp && prv) |
---|
567 | *commentp = xstrdup(filename); |
---|
568 | } else { |
---|
569 | /* it's a SSH v1 key if the public key part is readable */ |
---|
570 | key_free(pub); |
---|
571 | /* closes fd */ |
---|
572 | prv = key_load_private_rsa1(fd, filename, passphrase, NULL); |
---|
573 | } |
---|
574 | return prv; |
---|
575 | } |
---|
576 | |
---|
577 | static int |
---|
578 | key_try_load_public(Key *k, const char *filename, char **commentp) |
---|
579 | { |
---|
580 | FILE *f; |
---|
581 | char line[4096]; |
---|
582 | char *cp; |
---|
583 | |
---|
584 | f = fopen(filename, "r"); |
---|
585 | if (f != NULL) { |
---|
586 | while (fgets(line, sizeof(line), f)) { |
---|
587 | line[sizeof(line)-1] = '\0'; |
---|
588 | cp = line; |
---|
589 | switch(*cp){ |
---|
590 | case '#': |
---|
591 | case '\n': |
---|
592 | case '\0': |
---|
593 | continue; |
---|
594 | } |
---|
595 | /* Skip leading whitespace. */ |
---|
596 | for (; *cp && (*cp == ' ' || *cp == '\t'); cp++) |
---|
597 | ; |
---|
598 | if (*cp) { |
---|
599 | if (key_read(k, &cp) == 1) { |
---|
600 | if (commentp) |
---|
601 | *commentp=xstrdup(filename); |
---|
602 | fclose(f); |
---|
603 | return 1; |
---|
604 | } |
---|
605 | } |
---|
606 | } |
---|
607 | fclose(f); |
---|
608 | } |
---|
609 | return 0; |
---|
610 | } |
---|
611 | |
---|
612 | /* load public key from ssh v1 private or any pubkey file */ |
---|
613 | Key * |
---|
614 | key_load_public(const char *filename, char **commentp) |
---|
615 | { |
---|
616 | Key *pub; |
---|
617 | char file[MAXPATHLEN]; |
---|
618 | |
---|
619 | pub = key_load_public_type(KEY_RSA1, filename, commentp); |
---|
620 | if (pub != NULL) |
---|
621 | return pub; |
---|
622 | pub = key_new(KEY_UNSPEC); |
---|
623 | if (key_try_load_public(pub, filename, commentp) == 1) |
---|
624 | return pub; |
---|
625 | if ((strlcpy(file, filename, sizeof file) < sizeof(file)) && |
---|
626 | (strlcat(file, ".pub", sizeof file) < sizeof(file)) && |
---|
627 | (key_try_load_public(pub, file, commentp) == 1)) |
---|
628 | return pub; |
---|
629 | key_free(pub); |
---|
630 | return NULL; |
---|
631 | } |
---|