1/* vi: set sw=4 ts=4: */ 2/* 3 * popmaildir: a simple yet powerful POP3 client 4 * Delivers contents of remote mailboxes to local Maildir 5 * 6 * Inspired by original utility by Nikola Vladov 7 * 8 * Copyright (C) 2008 by Vladimir Dronnikov <dronnikov@gmail.com> 9 * 10 * Licensed under GPLv2, see file LICENSE in this source tree. 11 */ 12//config:config POPMAILDIR 13//config: bool "popmaildir (10 kb)" 14//config: default y 15//config: help 16//config: Simple yet powerful POP3 mail popper. Delivers content 17//config: of remote mailboxes to local Maildir. 18//config: 19//config:config FEATURE_POPMAILDIR_DELIVERY 20//config: bool "Allow message filters and custom delivery program" 21//config: default y 22//config: depends on POPMAILDIR 23//config: help 24//config: Allow to use a custom program to filter the content 25//config: of the message before actual delivery (-F "prog [args...]"). 26//config: Allow to use a custom program for message actual delivery 27//config: (-M "prog [args...]"). 28 29//applet:IF_POPMAILDIR(APPLET(popmaildir, BB_DIR_USR_SBIN, BB_SUID_DROP)) 30 31//kbuild:lib-$(CONFIG_POPMAILDIR) += popmaildir.o mail.o 32 33//usage:#define popmaildir_trivial_usage 34//usage: "[OPTIONS] MAILDIR [CONN_HELPER ARGS]" 35//usage:#define popmaildir_full_usage "\n\n" 36//usage: "Fetch content of remote mailbox to local maildir\n" 37/* //usage: "\n -b Binary mode. Ignored" */ 38/* //usage: "\n -d Debug. Ignored" */ 39/* //usage: "\n -m Show used memory. Ignored" */ 40/* //usage: "\n -V Show version. Ignored" */ 41/* //usage: "\n -c Use tcpclient. Ignored" */ 42/* //usage: "\n -a Use APOP protocol. Implied. If server supports APOP -> use it" */ 43//usage: "\n -s Skip authorization" 44//usage: "\n -T Get messages with TOP instead of RETR" 45//usage: "\n -k Keep retrieved messages on the server" 46//usage: "\n -t SEC Network timeout" 47//usage: IF_FEATURE_POPMAILDIR_DELIVERY( 48//usage: "\n -F 'PROG ARGS' Filter program (may be repeated)" 49//usage: "\n -M 'PROG ARGS' Delivery program" 50//usage: ) 51//usage: "\n" 52//usage: "\nFetch from plain POP3 server:" 53//usage: "\npopmaildir -k DIR nc pop3.server.com 110 <user_and_pass.txt" 54//usage: "\nFetch from SSLed POP3 server and delete fetched emails:" 55//usage: "\npopmaildir DIR -- openssl s_client -quiet -connect pop3.server.com:995 <user_and_pass.txt" 56/* //usage: "\n -R BYTES Remove old messages on the server >= BYTES. Ignored" */ 57/* //usage: "\n -Z N1-N2 Remove messages from N1 to N2 (dangerous). Ignored" */ 58/* //usage: "\n -L BYTES Don't retrieve new messages >= BYTES. Ignored" */ 59/* //usage: "\n -H LINES Type first LINES of a message. Ignored" */ 60//usage: 61//usage:#define popmaildir_example_usage 62//usage: "$ popmaildir -k ~/Maildir -- nc pop.drvv.ru 110 [<password_file]\n" 63//usage: "$ popmaildir ~/Maildir -- openssl s_client -quiet -connect pop.gmail.com:995 [<password_file]\n" 64 65#include "libbb.h" 66#include "mail.h" 67 68static void pop3_checkr(const char *fmt, const char *param, char **ret) 69{ 70 char *msg = send_mail_command(fmt, param); 71//FIXME: limit max len!!! 72 char *answer = xmalloc_fgetline(stdin); 73 if (answer && '+' == answer[0]) { 74 free(msg); 75 if (G.timeout) 76 alarm(0); 77 if (ret) { 78 // skip "+OK " 79 memmove(answer, answer + 4, strlen(answer) - 4); 80 *ret = answer; 81 } else 82 free(answer); 83 return; 84 } 85 bb_error_msg_and_die("%s failed, reply was: %s", msg, answer); 86} 87 88static void pop3_check(const char *fmt, const char *param) 89{ 90 pop3_checkr(fmt, param, NULL); 91} 92 93int popmaildir_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; 94int popmaildir_main(int argc UNUSED_PARAM, char **argv) 95{ 96 unsigned opts; 97 char *buf; 98 unsigned nmsg; 99 char *hostname; 100 pid_t pid; 101 const char *retr; 102#if ENABLE_FEATURE_POPMAILDIR_DELIVERY 103 const char *delivery; 104#endif 105 unsigned opt_nlines = 0; 106 107 enum { 108 OPT_b = 1 << 0, // -b binary mode. Ignored 109 OPT_d = 1 << 1, // -d,-dd,-ddd debug. Ignored 110 OPT_m = 1 << 2, // -m show used memory. Ignored 111 OPT_V = 1 << 3, // -V version. Ignored 112 OPT_c = 1 << 4, // -c use tcpclient. Ignored 113 OPT_a = 1 << 5, // -a use APOP protocol 114 OPT_s = 1 << 6, // -s skip authorization 115 OPT_T = 1 << 7, // -T get messages with TOP instead with RETR 116 OPT_k = 1 << 8, // -k keep retrieved messages on the server 117 OPT_t = 1 << 9, // -t90 set timeout to 90 sec 118 OPT_R = 1 << 10, // -R20000 remove old messages on the server >= 20000 bytes (requires -k). Ignored 119 OPT_Z = 1 << 11, // -Z11-23 remove messages from 11 to 23 (dangerous). Ignored 120 OPT_L = 1 << 12, // -L50000 not retrieve new messages >= 50000 bytes. Ignored 121 OPT_H = 1 << 13, // -H30 type first 30 lines of a message; (-L12000 -H30). Ignored 122 OPT_M = 1 << 14, // -M\"program arg1 arg2 ...\"; deliver by program. Treated like -F 123 OPT_F = 1 << 15, // -F\"program arg1 arg2 ...\"; filter by program. Treated like -M 124 }; 125 126 // init global variables 127 INIT_G(); 128 129 // parse options 130 opts = getopt32(argv, "^" 131 "bdmVcasTkt:+" "R:+Z:L:+H:+" IF_FEATURE_POPMAILDIR_DELIVERY("M:F:") 132 "\0" "-1:dd", 133 &G.timeout, NULL, NULL, NULL, &opt_nlines 134 IF_FEATURE_POPMAILDIR_DELIVERY(, &delivery, &delivery) // we treat -M and -F the same 135 ); 136 //argc -= optind; 137 argv += optind; 138 139 // get auth info 140 if (!(opts & OPT_s)) 141 get_cred_or_die(STDIN_FILENO); 142 143 // goto maildir 144 xchdir(*argv++); 145 146 // launch connect helper, if any 147 if (*argv) 148 launch_helper((const char **)argv); 149 150 // get server greeting 151 pop3_checkr(NULL, NULL, &buf); 152 153 // authenticate (if no -s given) 154 if (!(opts & OPT_s)) { 155 // server supports APOP and we want it? 156 if ('<' == buf[0] && (opts & OPT_a)) { 157 union { // save a bit of stack 158 md5_ctx_t ctx; 159 char hex[16 * 2 + 1]; 160 } md5; 161 uint32_t res[MD5_OUTSIZE / 4]; 162 163 char *s = strchr(buf, '>'); 164 if (s) 165 s[1] = '\0'; 166 // get md5 sum of "<stamp>password" string 167 md5_begin(&md5.ctx); 168 md5_hash(&md5.ctx, buf, strlen(buf)); 169 md5_hash(&md5.ctx, G.pass, strlen(G.pass)); 170 md5_end(&md5.ctx, res); 171 *bin2hex(md5.hex, (char*)res, 16) = '\0'; 172 // APOP 173 s = xasprintf("%s %s", G.user, md5.hex); 174 pop3_check("APOP %s", s); 175 free(s); 176 free(buf); 177 // server ignores APOP -> use simple text authentication 178 } else { 179 // USER 180 pop3_check("USER %s", G.user); 181 // PASS 182 pop3_check("PASS %s", G.pass); 183 } 184 } 185 186 // get mailbox statistics 187 pop3_checkr("STAT", NULL, &buf); 188 189 // prepare message filename suffix 190 hostname = safe_gethostname(); 191 pid = getpid(); 192 193 // get messages counter 194 // NOTE: we don't use xatou(buf) since buf is "nmsg nbytes" 195 // we only need nmsg and atoi is just exactly what we need 196 // if atoi fails to convert buf into number it returns 0 197 // in this case the following loop simply will not be executed 198 nmsg = atoi(buf); 199 free(buf); 200 201 // loop through messages 202 retr = (opts & OPT_T) ? xasprintf("TOP %%u %u", opt_nlines) : "RETR %u"; 203 for (; nmsg; nmsg--) { 204 205 char *filename; 206 char *target; 207 char *answer; 208 FILE *fp; 209#if ENABLE_FEATURE_POPMAILDIR_DELIVERY 210 int rc; 211#endif 212 // generate unique filename 213 filename = xasprintf("tmp/%llu.%u.%s", 214 monotonic_us(), (unsigned)pid, hostname); 215 216 // retrieve message in ./tmp/ unless filter is specified 217 pop3_check(retr, (const char *)(ptrdiff_t)nmsg); 218 219#if ENABLE_FEATURE_POPMAILDIR_DELIVERY 220 // delivery helper ordered? -> setup pipe 221 if (opts & (OPT_F|OPT_M)) { 222 // helper will have $FILENAME set to filename 223 xsetenv("FILENAME", filename); 224 fp = popen(delivery, "w"); 225 unsetenv("FILENAME"); 226 if (!fp) { 227 bb_simple_perror_msg("delivery helper"); 228 break; 229 } 230 } else 231#endif 232 // create and open file filename 233 fp = xfopen_for_write(filename); 234 235 // copy stdin to fp (either filename or delivery helper) 236 while ((answer = xmalloc_fgets_str(stdin, "\r\n")) != NULL) { 237 char *s = answer; 238 if ('.' == answer[0]) { 239 if ('.' == answer[1]) 240 s++; 241 else if ('\r' == answer[1] && '\n' == answer[2] && '\0' == answer[3]) 242 break; 243 } 244 //*strchrnul(s, '\r') = '\n'; 245 fputs(s, fp); 246 free(answer); 247 } 248 249#if ENABLE_FEATURE_POPMAILDIR_DELIVERY 250 // analyse delivery status 251 if (opts & (OPT_F|OPT_M)) { 252 rc = pclose(fp); 253 if (99 == rc) // 99 means bail out 254 break; 255// if (rc) // !0 means skip to the next message 256 goto skip; 257// // 0 means continue 258 } else { 259 // close filename 260 fclose(fp); 261 } 262#endif 263 264 // delete message from server 265 if (!(opts & OPT_k)) 266 pop3_check("DELE %u", (const char*)(ptrdiff_t)nmsg); 267 268 // atomically move message to ./new/ 269 target = xstrdup(filename); 270 memcpy(target, "new", 3); 271 // ... or just stop receiving on failure 272 if (rename_or_warn(filename, target)) 273 break; 274 free(target); 275 276#if ENABLE_FEATURE_POPMAILDIR_DELIVERY 277 skip: 278#endif 279 free(filename); 280 } 281 282 // Bye 283 pop3_check("QUIT", NULL); 284 285 if (ENABLE_FEATURE_CLEAN_UP) { 286 free(G.user); 287 free(G.pass); 288 } 289 290 return EXIT_SUCCESS; 291} 292