diff options
| -rw-r--r-- | mailutils/sendmail.c | 67 |
1 files changed, 56 insertions, 11 deletions
diff --git a/mailutils/sendmail.c b/mailutils/sendmail.c index b5aa1d1..824109d 100644 --- a/mailutils/sendmail.c +++ b/mailutils/sendmail.c @@ -15,7 +15,8 @@ //usage: "Read email from stdin and send it\n" //usage: "\nStandard options:" //usage: "\n -t Read additional recipients from message body" -//usage: "\n -f SENDER Sender (required)" +//usage: "\n -f SENDER For use in MAIL FROM:<sender>. Can be empty string" +//usage: "\n Default: -auUSER, or username of current UID" //usage: "\n -o OPTIONS Various options. -oi implied, others are ignored" //usage: "\n -i -oi synonym. implied and ignored" //usage: "\n" @@ -40,6 +41,52 @@ //usage: "\nUse makemime to create emails with attachments" //usage: ) +/* Currently we don't sanitize or escape user-supplied SENDER and RECIPIENT_EMAILs. + * We may need to do so. For one, '.' in usernames seems to require escaping! + * + * From http://cr.yp.to/smtp/address.html: + * + * SMTP offers three ways to encode a character inside an address: + * + * "safe": the character, if it is not <>()[].,;:@, backslash, + * double-quote, space, or an ASCII control character; + * "quoted": the character, if it is not \012, \015, backslash, + * or double-quote; or + * "slashed": backslash followed by the character. + * + * An encoded box part is either (1) a sequence of one or more slashed + * or safe characters or (2) a double quote, a sequence of zero or more + * slashed or quoted characters, and a double quote. It represents + * the concatenation of the characters encoded inside it. + * + * For example, the encoded box parts + * angels + * \a\n\g\e\l\s + * "\a\n\g\e\l\s" + * "angels" + * "ang\els" + * all represent the 6-byte string "angels", and the encoded box parts + * a\,comma + * \a\,\c\o\m\m\a + * "a,comma" + * all represent the 7-byte string "a,comma". + * + * An encoded address contains + * the byte <; + * optionally, a route followed by a colon; + * an encoded box part, the byte @, and a domain; and + * the byte >. + * + * It represents an Internet mail address, given by concatenating + * the string represented by the encoded box part, the byte @, + * and the domain. For example, the encoded addresses + * <God@heaven.af.mil> + * <\God@heaven.af.mil> + * <"God"@heaven.af.mil> + * <@gateway.af.mil,@uucp.local:"\G\o\d"@heaven.af.mil> + * all represent the Internet mail address "God@heaven.af.mil". + */ + #include "libbb.h" #include "mail.h" @@ -163,7 +210,7 @@ int sendmail_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; int sendmail_main(int argc UNUSED_PARAM, char **argv) { char *opt_connect = opt_connect; - char *opt_from; + char *opt_from = NULL; char *s; llist_t *list = NULL; char *host = sane_address(safe_gethostname()); @@ -199,8 +246,8 @@ int sendmail_main(int argc UNUSED_PARAM, char **argv) G.fp0 = xfdopen_for_read(3); // parse options - // -v is a counter, -f is required. -H and -S are mutually exclusive, -a is a list - opt_complementary = "vv:f:w+:H--S:S--H:a::"; + // -v is a counter, -H and -S are mutually exclusive, -a is a list + opt_complementary = "vv:w+:H--S:S--H:a::"; // N.B. since -H and -S are mutually exclusive they do not interfere in opt_connect // -a is for ssmtp (http://downloads.openwrt.org/people/nico/man/man8/ssmtp.8.html) compatibility, // it is still under development. @@ -304,13 +351,11 @@ int sendmail_main(int argc UNUSED_PARAM, char **argv) // Since reading from console may defeat usability, the solution is either to read from a predefined // file descriptor (e.g. 4), or again from a secured file. - // got no sender address? -> use system username as a resort - // N.B. we marked -f as required option! - //if (!G.user) { - // // N.B. IMHO getenv("USER") can be way easily spoofed! - // G.user = xuid2uname(getuid()); - // opt_from = xasprintf("%s@%s", G.user, domain); - //} + // got no sender address? use auth name, then UID username as a last resort + if (!opt_from) { + opt_from = G.user ? G.user : xuid2uname(getuid()); + } + smtp_checkp("MAIL FROM:<%s>", opt_from, 250); // process message |