/* vi: set sw=4 ts=4: */ /* * reformime: parse MIME-encoded message * * Copyright (C) 2008 by Vladimir Dronnikov <dronnikov@gmail.com> * * Licensed under GPLv2, see file LICENSE in this source tree. */ //config:config REFORMIME //config: bool "reformime (7.5 kb)" //config: default y //config: help //config: Parse MIME-formatted messages. //config: //config:config FEATURE_REFORMIME_COMPAT //config: bool "Accept and ignore options other than -x and -X" //config: default y //config: depends on REFORMIME //config: help //config: Accept (for compatibility only) and ignore options //config: other than -x and -X. //applet:IF_REFORMIME(APPLET(reformime, BB_DIR_BIN, BB_SUID_DROP)) //kbuild:lib-$(CONFIG_REFORMIME) += reformime.o mail.o #include "libbb.h" #include "mail.h" #if 0 # define dbg_error_msg(...) bb_error_msg(__VA_ARGS__) #else # define dbg_error_msg(...) ((void)0) #endif static const char *find_token(const char *const string_array[], const char *key, const char *defvalue) { const char *r = NULL; int i; for (i = 0; string_array[i] != NULL; i++) { if (strcasecmp(string_array[i], key) == 0) { r = (char *)string_array[i+1]; break; } } return (r) ? r : defvalue; } static const char *xfind_token(const char *const string_array[], const char *key) { const char *r = find_token(string_array, key, NULL); if (r) return r; bb_error_msg_and_die("not found: '%s'", key); } enum { OPT_x = 1 << 0, OPT_X = 1 << 1, #if ENABLE_FEATURE_REFORMIME_COMPAT OPT_d = 1 << 2, OPT_e = 1 << 3, OPT_i = 1 << 4, OPT_s = 1 << 5, OPT_r = 1 << 6, OPT_c = 1 << 7, OPT_m = 1 << 8, OPT_h = 1 << 9, OPT_o = 1 << 10, OPT_O = 1 << 11, #endif }; static int parse(const char *boundary, char **argv) { int boundary_len = strlen(boundary); char uniq[sizeof("%%llu.%u") + sizeof(int)*3]; dbg_error_msg("BOUNDARY[%s]", boundary); // prepare unique string pattern sprintf(uniq, "%%llu.%u", (unsigned)getpid()); dbg_error_msg("UNIQ[%s]", uniq); while (1) { char *header; const char *tokens[32]; /* 32 is enough */ const char *type; /* Read the header (everything up to two \n) */ { unsigned header_idx = 0; int last_ch = 0; header = NULL; while (1) { int ch = fgetc(stdin); if (ch == '\r') /* Support both line endings */ continue; if (ch == EOF) break; if (ch == '\n' && last_ch == ch) break; if (!(header_idx & 0xff)) header = xrealloc(header, header_idx + 0x101); header[header_idx++] = last_ch = ch; } if (!header) { dbg_error_msg("EOF"); break; } header[header_idx] = '\0'; dbg_error_msg("H:'%s'", p); } /* Split to tokens */ { char *s, *p; unsigned ntokens; const char *delims = ";=\" \t\n"; /* Skip to last Content-Type: */ s = p = header; while ((p = strchr(p, '\n')) != NULL) { p++; if (strncasecmp(p, "Content-Type:", sizeof("Content-Type:")-1) == 0) s = p; } dbg_error_msg("L:'%s'", p); ntokens = 0; s = strtok(s, delims); while (s) { tokens[ntokens] = s; if (ntokens < ARRAY_SIZE(tokens) - 1) ntokens++; dbg_error_msg("L[%d]='%s'", ntokens, s); s = strtok(NULL, delims); } tokens[ntokens] = NULL; dbg_error_msg("EMPTYLINE, ntokens:%d", ntokens); if (ntokens == 0) break; } /* Is it multipart? */ type = find_token(tokens, "Content-Type:", "text/plain"); dbg_error_msg("TYPE:'%s'", type); if (0 == strncasecmp(type, "multipart/", 10)) { /* Yes, recurse */ if (strcasecmp(type + 10, "mixed") != 0) bb_error_msg_and_die("no support of content type '%s'", type); parse(xfind_token(tokens, "boundary"), argv); } else { /* No, process one non-multipart section */ char *end; pid_t pid = pid; FILE *fp; const char *charset = find_token(tokens, "charset", CONFIG_FEATURE_MIME_CHARSET); const char *encoding = find_token(tokens, "Content-Transfer-Encoding:", "7bit"); /* Compose target filename */ char *filename = (char *)find_token(tokens, "filename", NULL); if (!filename) filename = xasprintf(uniq, monotonic_us()); else filename = bb_get_last_path_component_strip(xstrdup(filename)); if (opts & OPT_X) { int fd[2]; /* start external helper */ xpipe(fd); pid = vfork(); if (0 == pid) { /* child reads from fd[0] */ close(fd[1]); xmove_fd(fd[0], STDIN_FILENO); xsetenv("CONTENT_TYPE", type); xsetenv("CHARSET", charset); xsetenv("ENCODING", encoding); xsetenv("FILENAME", filename); BB_EXECVP_or_die(argv); } /* parent will write to fd[1] */ close(fd[0]); fp = xfdopen_for_write(fd[1]); signal(SIGPIPE, SIG_IGN); } else { /* write to file */ char *fname = xasprintf("%s%s", *argv, filename); fp = xfopen_for_write(fname); free(fname); } free(filename); /* write to fp */ end = NULL; if (0 == strcasecmp(encoding, "base64")) { read_base64(stdin, fp, '-'); } else if (0 != strcasecmp(encoding, "7bit") && 0 != strcasecmp(encoding, "8bit") ) { /* quoted-printable, binary, user-defined are unsupported so far */ bb_error_msg_and_die("encoding '%s' not supported", encoding); } else { /* plain 7bit or 8bit */ while ((end = xmalloc_fgets(stdin)) != NULL) { if ('-' == end[0] && '-' == end[1] && strncmp(end + 2, boundary, boundary_len) == 0 ) { break; } fputs(end, fp); } } fclose(fp); /* Wait for child */ if (opts & OPT_X) { int rc; signal(SIGPIPE, SIG_DFL); rc = (wait4pid(pid) & 0xff); if (rc != 0) return rc + 20; } /* Multipart ended? */ if (end && '-' == end[2 + boundary_len] && '-' == end[2 + boundary_len + 1]) { dbg_error_msg("FINISHED MPART:'%s'", end); break; } dbg_error_msg("FINISHED:'%s'", end); free(end); } /* end of "handle one non-multipart block" */ free(header); } /* while (1) */ dbg_error_msg("ENDPARSE[%s]", boundary); return EXIT_SUCCESS; } //usage:#define reformime_trivial_usage //usage: "[OPTIONS]" //usage:#define reformime_full_usage "\n\n" //usage: "Parse MIME-encoded message on stdin\n" //usage: "\n -x PREFIX Extract content of MIME sections to files" //usage: "\n -X PROG ARGS Filter content of MIME sections through PROG" //usage: "\n Must be the last option" //usage: "\n" //usage: "\nOther options are silently ignored" /* Usage: reformime [options] -d - parse a delivery status notification. -e - extract contents of MIME section. -x - extract MIME section to a file. -X - pipe MIME section to a program. -i - show MIME info. -s n.n.n.n - specify MIME section. -r - rewrite message, filling in missing MIME headers. -r7 - also convert 8bit/raw encoding to quoted-printable, if possible. -r8 - also convert quoted-printable encoding to 8bit, if possible. -c charset - default charset for rewriting, -o, and -O. -m [file] [file]... - create a MIME message digest. -h "header" - decode RFC 2047-encoded header. -o "header" - encode unstructured header using RFC 2047. -O "header" - encode address list header using RFC 2047. */ int reformime_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; int reformime_main(int argc UNUSED_PARAM, char **argv) { const char *opt_prefix = ""; INIT_G(); // parse options // N.B. only -x and -X are supported so far opts = getopt32(argv, "^" "x:X" IF_FEATURE_REFORMIME_COMPAT("deis:r:c:m:*h:o:O:") "\0" "x--X:X--x", &opt_prefix IF_FEATURE_REFORMIME_COMPAT(, NULL, NULL, &G.opt_charset, NULL, NULL, NULL, NULL) ); argv += optind; return parse("", (opts & OPT_X) ? argv : (char **)&opt_prefix); }