diff options
| -rw-r--r-- | Makefile | 11 | ||||
| -rw-r--r-- | TARGETS | 1 | ||||
| -rw-r--r-- | base64.c | 90 | ||||
| -rw-r--r-- | base64.h | 7 | ||||
| -rw-r--r-- | qmail-smtpd.8 | 32 | ||||
| -rw-r--r-- | qmail-smtpd.c | 265 |
6 files changed, 390 insertions, 16 deletions
@@ -136,6 +136,10 @@ auto_usera.o: \ compile auto_usera.c ./compile auto_usera.c +base64.o: \ +compile base64.c base64.h stralloc.h substdio.h str.h + ./compile base64.c + binm1: \ binm1.sh conf-qmail cat binm1.sh \ @@ -1536,12 +1540,12 @@ load qmail-smtpd.o rcpthosts.o commands.o timeoutread.o \ timeoutwrite.o ip.o ipme.o ipalloc.o control.o constmap.o received.o \ date822fmt.o now.o qmail.o cdb.a fd.a wait.a datetime.a getln.a \ open.a sig.a case.a env.a stralloc.a alloc.a substdio.a error.a str.a \ -fs.a auto_qmail.o socket.lib +fs.a auto_qmail.o base64.o socket.lib ./load qmail-smtpd rcpthosts.o commands.o timeoutread.o \ timeoutwrite.o ip.o ipme.o ipalloc.o control.o constmap.o \ received.o date822fmt.o now.o qmail.o cdb.a fd.a wait.a \ datetime.a getln.a open.a sig.a case.a env.a stralloc.a \ - alloc.a substdio.a error.a str.a fs.a auto_qmail.o `cat \ + alloc.a substdio.a error.a str.a fs.a auto_qmail.o base64.o `cat \ socket.lib` qmail-smtpd.0: \ @@ -1553,7 +1557,8 @@ compile qmail-smtpd.c sig.h readwrite.h stralloc.h gen_alloc.h \ substdio.h alloc.h auto_qmail.h control.h received.h constmap.h \ error.h ipme.h ip.h ipalloc.h ip.h gen_alloc.h ip.h qmail.h \ substdio.h str.h fmt.h scan.h byte.h case.h env.h now.h datetime.h \ -exit.h rcpthosts.h timeoutread.h timeoutwrite.h commands.h +exit.h rcpthosts.h timeoutread.h timeoutwrite.h commands.h wait.h \ +fd.h base64.h ./compile qmail-smtpd.c qmail-start: \ @@ -250,6 +250,7 @@ qmail-qmqpd qmail-qmtpd.o rcpthosts.o qmail-qmtpd +base64.o qmail-smtpd.o qmail-smtpd sendmail.o diff --git a/base64.c b/base64.c new file mode 100644 index 0000000..fbce145 --- /dev/null +++ b/base64.c @@ -0,0 +1,90 @@ +#include "base64.h" +#include "stralloc.h" +#include "substdio.h" +#include "str.h" + +static char *b64alpha = + "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; +#define B64PAD '=' + +/* returns 0 ok, 1 illegal, -1 problem */ + +int b64decode(in,l,out) +const unsigned char *in; +int l; +stralloc *out; /* not null terminated */ +{ + int i, j; + unsigned char a[4]; + unsigned char b[3]; + char *s; + + if (l == 0) + { + if (!stralloc_copys(out,"")) return -1; + return 0; + } + + if (!stralloc_ready(out,l + 2)) return -1; /* XXX generous */ + s = out->s; + + for (i = 0;i < l;i += 4) { + for (j = 0;j < 4;j++) + if ((i + j) < l && in[i + j] != B64PAD) + { + a[j] = str_chr(b64alpha,in[i + j]); + if (a[j] > 63) return 1; + } + else a[j] = 0; + + b[0] = (a[0] << 2) | (a[1] >> 4); + b[1] = (a[1] << 4) | (a[2] >> 2); + b[2] = (a[2] << 6) | (a[3]); + + *s++ = b[0]; + + if (in[i + 1] == B64PAD) break; + *s++ = b[1]; + + if (in[i + 2] == B64PAD) break; + *s++ = b[2]; + } + out->len = s - out->s; + while (out->len && !out->s[out->len - 1]) --out->len; /* XXX avoid? */ + return 0; +} + +int b64encode(in,out) +stralloc *in; +stralloc *out; /* not null terminated */ +{ + unsigned char a, b, c; + int i; + char *s; + + if (in->len == 0) + { + if (!stralloc_copys(out,"")) return -1; + return 0; + } + + if (!stralloc_ready(out,in->len / 3 * 4 + 4)) return -1; + s = out->s; + + for (i = 0;i < in->len;i += 3) { + a = in->s[i]; + b = i + 1 < in->len ? in->s[i + 1] : 0; + c = i + 2 < in->len ? in->s[i + 2] : 0; + + *s++ = b64alpha[a >> 2]; + *s++ = b64alpha[((a & 3 ) << 4) | (b >> 4)]; + + if (i + 1 >= in->len) *s++ = B64PAD; + else *s++ = b64alpha[((b & 15) << 2) | (c >> 6)]; + + if (i + 2 >= in->len) *s++ = B64PAD; + else *s++ = b64alpha[c & 63]; + } + out->len = s - out->s; + return 0; +} diff --git a/base64.h b/base64.h new file mode 100644 index 0000000..a9164c0 --- /dev/null +++ b/base64.h @@ -0,0 +1,7 @@ +#ifndef BASE64_H +#define BASE64_H + +extern int b64decode(); +extern int b64encode(); + +#endif diff --git a/qmail-smtpd.8 b/qmail-smtpd.8 index c4640b8..3e6cce2 100644 --- a/qmail-smtpd.8 +++ b/qmail-smtpd.8 @@ -3,6 +3,11 @@ qmail-smtpd \- receive mail via SMTP .SH SYNOPSIS .B qmail-smtpd +[ +.I hostname +.I checkprogram +.I subprogram +] .SH DESCRIPTION .B qmail-smtpd receives mail messages via the Simple Mail Transfer Protocol (SMTP) @@ -23,7 +28,29 @@ or header fields. .B qmail-smtpd -supports ESMTP, including the 8BITMIME and PIPELINING options. +supports ESMTP, including the 8BITMIME, PIPELINING, and AUTH options. + +.B qmail-smtpd +can accept LOGIN, PLAIN, and CRAM-MD5 AUTH types. It invokes +.IR checkprogram , +which reads on file descriptor 3 the username, a 0 byte, the password +or challenge derived from +.IR hostname , +another 0 byte, a CRAM-MD5 response (if applicable to the AUTH type), +and a final 0 byte. +.I checkprogram +invokes +.I subprogram +upon successful authentication, which should in turn return 0 to +.BR qmail-smtpd , +effectively setting the environment variables RELAYCLIENT and TCPREMOTEINFO +(any supplied value replaced with the authenticated username). +.B qmail-smtpd +will reject the authentication attempt if it receives a nonzero return +value from +.I checkprogram +or +.IR subprogram . .SH TRANSPARENCY .B qmail-smtpd converts the SMTP newline convention into the UNIX newline convention @@ -177,3 +204,6 @@ qmail-inject(8), qmail-newmrh(8), qmail-queue(8), qmail-remote(8) +.SH "HISTORY" +The patch enabling the ESMTP AUTH option is not part of the standard +qmail-1.03 distribution. diff --git a/qmail-smtpd.c b/qmail-smtpd.c index 54df00c..7390eb4 100644 --- a/qmail-smtpd.c +++ b/qmail-smtpd.c @@ -23,7 +23,10 @@ #include "timeoutread.h" #include "timeoutwrite.h" #include "commands.h" +#include "wait.h" +#include "fd.h" +#define AUTHCRAM #define MAXHOPS 100 unsigned int databytes = 0; int timeout = 1200; @@ -59,6 +62,15 @@ void err_noop(arg) char *arg; { out("250 ok\r\n"); } void err_vrfy(arg) char *arg; { out("252 send some mail, i'll try my best\r\n"); } void err_qqt() { out("451 qqt failure (#4.3.0)\r\n"); } +int err_child() { out("454 oops, problem with child and I can't auth (#4.3.0)\r\n"); return -1; } +int err_fork() { out("454 oops, child won't start and I can't auth (#4.3.0)\r\n"); return -1; } +int err_pipe() { out("454 oops, unable to open pipe and I can't auth (#4.3.0)\r\n"); return -1; } +int err_write() { out("454 oops, unable to write pipe and I can't auth (#4.3.0)\r\n"); return -1; } +void err_authd() { out("503 you're already authenticated (#5.5.0)\r\n"); } +void err_authmail() { out("503 no auth during mail transaction (#5.5.0)\r\n"); } +int err_noauth() { out("504 auth type unimplemented (#5.5.1)\r\n"); return -1; } +int err_authabrt() { out("501 auth exchange cancelled (#5.0.0)\r\n"); return -1; } +int err_input() { out("501 malformed auth input (#5.5.4)\r\n"); return -1; } stralloc greeting = {0}; @@ -86,8 +98,8 @@ stralloc helohost = {0}; char *fakehelo; /* pointer into helohost, or 0 */ void dohelo(arg) char *arg; { - if (!stralloc_copys(&helohost,arg)) die_nomem(); - if (!stralloc_0(&helohost)) die_nomem(); + if (!stralloc_copys(&helohost,arg)) die_nomem(); + if (!stralloc_0(&helohost)) die_nomem(); fakehelo = case_diffs(remotehost,helohost.s) ? helohost.s : 0; } @@ -101,7 +113,7 @@ void setup() { char *x; unsigned long u; - + if (control_init() == -1) die_control(); if (control_rldef(&greeting,"control/smtpgreeting",1,(char *) 0) != 1) die_control(); @@ -116,12 +128,12 @@ void setup() if (bmfok == -1) die_control(); if (bmfok) if (!constmap_init(&mapbmf,bmf.s,bmf.len,0)) die_nomem(); - + if (control_readint(&databytes,"control/databytes") == -1) die_control(); x = env_get("DATABYTES"); if (x) { scan_ulong(x,&u); databytes = u; } if (!(databytes + 1)) --databytes; - + remoteip = env_get("TCPREMOTEIP"); if (!remoteip) remoteip = "unknown"; local = env_get("TCPLOCALHOST"); @@ -146,7 +158,7 @@ char *arg; struct ip_address ip; int flagesc; int flagquoted; - + terminator = '>'; i = str_chr(arg,'<'); if (arg[i]) @@ -229,7 +241,15 @@ void smtp_helo(arg) char *arg; } void smtp_ehlo(arg) char *arg; { - smtp_greet("250-"); out("\r\n250-PIPELINING\r\n250 8BITMIME\r\n"); + smtp_greet("250-"); +#ifdef AUTHCRAM + out("\r\n250-AUTH LOGIN CRAM-MD5 PLAIN"); + out("\r\n250-AUTH=LOGIN CRAM-MD5 PLAIN"); +#else + out("\r\n250-AUTH LOGIN PLAIN"); + out("\r\n250-AUTH=LOGIN PLAIN"); +#endif + out("\r\n250-PIPELINING\r\n250 8BITMIME\r\n"); seenmail = 0; dohelo(arg); } void smtp_rset(arg) char *arg; @@ -300,7 +320,7 @@ int *hops; int flagmaybex; /* 1 if this line might match RECEIVED, if fih */ int flagmaybey; /* 1 if this line might match \r\n, if fih */ int flagmaybez; /* 1 if this line might match DELIVERED, if fih */ - + state = 1; *hops = 0; flaginheader = 1; @@ -369,7 +389,7 @@ void smtp_data(arg) char *arg; { int hops; unsigned long qp; char *qqx; - + if (!seenmail) { err_wantmail(); return; } if (!rcptto.len) { err_wantrcpt(); return; } seenmail = 0; @@ -377,14 +397,14 @@ void smtp_data(arg) char *arg; { if (qmail_open(&qqt) == -1) { err_qqt(); return; } qp = qmail_qp(&qqt); out("354 go ahead\r\n"); - + received(&qqt,"SMTP",local,remoteip,remotehost,remoteinfo,fakehelo); blast(&hops); hops = (hops >= MAXHOPS); if (hops) qmail_fail(&qqt); qmail_from(&qqt,mailfrom.s); qmail_put(&qqt,rcptto.s,rcptto.len); - + qqx = qmail_close(&qqt); if (!*qqx) { acceptmessage(qp); return; } if (hops) { out("554 too many hops, this message is looping (#5.4.6)\r\n"); return; } @@ -394,10 +414,226 @@ void smtp_data(arg) char *arg; { out("\r\n"); } + +char unique[FMT_ULONG + FMT_ULONG + 3]; +static stralloc authin = {0}; +static stralloc user = {0}; +static stralloc pass = {0}; +static stralloc resp = {0}; +static stralloc slop = {0}; +char *hostname; +char **childargs; +substdio ssup; +char upbuf[128]; +int authd = 0; + +int authgetl(void) { + int i; + + if (!stralloc_copys(&authin, "")) die_nomem(); + + for (;;) { + if (!stralloc_readyplus(&authin,1)) die_nomem(); /* XXX */ + i = substdio_get(&ssin,authin.s + authin.len,1); + if (i != 1) die_read(); + if (authin.s[authin.len] == '\n') break; + ++authin.len; + } + + if (authin.len > 0) if (authin.s[authin.len - 1] == '\r') --authin.len; + authin.s[authin.len] = 0; + + if (*authin.s == '*' && *(authin.s + 1) == 0) { return err_authabrt(); } + if (authin.len == 0) { return err_input(); } + return authin.len; +} + +int authenticate(void) +{ + int child; + int wstat; + int pi[2]; + + if (!stralloc_0(&user)) die_nomem(); + if (!stralloc_0(&pass)) die_nomem(); + if (!stralloc_0(&resp)) die_nomem(); + + if (fd_copy(2,1) == -1) return err_pipe(); + close(3); + if (pipe(pi) == -1) return err_pipe(); + if (pi[0] != 3) return err_pipe(); + switch(child = fork()) { + case -1: + return err_fork(); + case 0: + close(pi[1]); + sig_pipedefault(); + execvp(*childargs, childargs); + _exit(1); + } + close(pi[0]); + + substdio_fdbuf(&ssup,write,pi[1],upbuf,sizeof upbuf); + if (substdio_put(&ssup,user.s,user.len) == -1) return err_write(); + if (substdio_put(&ssup,pass.s,pass.len) == -1) return err_write(); + if (substdio_put(&ssup,resp.s,resp.len) == -1) return err_write(); + if (substdio_flush(&ssup) == -1) return err_write(); + + close(pi[1]); + byte_zero(pass.s,pass.len); + byte_zero(upbuf,sizeof upbuf); + if (wait_pid(&wstat,child) == -1) return err_child(); + if (wait_crashed(wstat)) return err_child(); + if (wait_exitcode(wstat)) { sleep(5); return 1; } /* no */ + return 0; /* yes */ +} + +int auth_login(arg) char *arg; +{ + int r; + + if (*arg) { + if (r = b64decode(arg,str_len(arg),&user) == 1) return err_input(); + } + else { + out("334 VXNlcm5hbWU6\r\n"); flush(); /* Username: */ + if (authgetl() < 0) return -1; + if (r = b64decode(authin.s,authin.len,&user) == 1) return err_input(); + } + if (r == -1) die_nomem(); + + out("334 UGFzc3dvcmQ6\r\n"); flush(); /* Password: */ + + if (authgetl() < 0) return -1; + if (r = b64decode(authin.s,authin.len,&pass) == 1) return err_input(); + if (r == -1) die_nomem(); + + if (!user.len || !pass.len) return err_input(); + return authenticate(); +} + +int auth_plain(arg) char *arg; +{ + int r, id = 0; + + if (*arg) { + if (r = b64decode(arg,str_len(arg),&slop) == 1) return err_input(); + } + else { + out("334 \r\n"); flush(); + if (authgetl() < 0) return -1; + if (r = b64decode(authin.s,authin.len,&slop) == 1) return err_input(); + } + if (r == -1 || !stralloc_0(&slop)) die_nomem(); + while (slop.s[id]) id++; /* ignore authorize-id */ + + if (slop.len > id + 1) + if (!stralloc_copys(&user,slop.s + id + 1)) die_nomem(); + if (slop.len > id + user.len + 2) + if (!stralloc_copys(&pass,slop.s + id + user.len + 2)) die_nomem(); + + if (!user.len || !pass.len) return err_input(); + return authenticate(); +} + +#ifdef AUTHCRAM +int auth_cram() +{ + int i, r; + char *s; + + s = unique; + s += fmt_uint(s,getpid()); + *s++ = '.'; + s += fmt_ulong(s,(unsigned long) now()); + *s++ = '@'; + *s++ = 0; + + if (!stralloc_copys(&pass,"<")) die_nomem(); + if (!stralloc_cats(&pass,unique)) die_nomem(); + if (!stralloc_cats(&pass,hostname)) die_nomem(); + if (!stralloc_cats(&pass,">")) die_nomem(); + if (b64encode(&pass,&slop) < 0) die_nomem(); + if (!stralloc_0(&slop)) die_nomem(); + + out("334 "); + out(slop.s); + out("\r\n"); + flush(); + + if (authgetl() < 0) return -1; + if (r = b64decode(authin.s,authin.len,&slop) == 1) return err_input(); + if (r == -1 || !stralloc_0(&slop)) die_nomem(); + + i = str_chr(slop.s,' '); + s = slop.s + i; + while (*s == ' ') ++s; + slop.s[i] = 0; + if (!stralloc_copys(&user,slop.s)) die_nomem(); + if (!stralloc_copys(&resp,s)) die_nomem(); + + if (!user.len || !resp.len) return err_input(); + return authenticate(); +} +#endif + +struct authcmd { + char *text; + int (*fun)(); +} authcmds[] = { + { "login", auth_login } +, { "plain", auth_plain } +#ifdef AUTHCRAM +, { "cram-md5", auth_cram } +#endif +, { 0, err_noauth } +}; + +void smtp_auth(arg) +char *arg; +{ + int i; + char *cmd = arg; + + if (!hostname || !*childargs) + { + out("503 auth not available (#5.3.3)\r\n"); + return; + } + if (authd) { err_authd(); return; } + if (seenmail) { err_authmail(); return; } + + if (!stralloc_copys(&user,"")) die_nomem(); + if (!stralloc_copys(&pass,"")) die_nomem(); + if (!stralloc_copys(&resp,"")) die_nomem(); + + i = str_chr(cmd,' '); + arg = cmd + i; + while (*arg == ' ') ++arg; + cmd[i] = 0; + + for (i = 0;authcmds[i].text;++i) + if (case_equals(authcmds[i].text,cmd)) break; + + switch (authcmds[i].fun(arg)) { + case 0: + authd = 1; + relayclient = ""; + remoteinfo = user.s; + if (!env_unset("TCPREMOTEINFO")) die_read(); + if (!env_put2("TCPREMOTEINFO",remoteinfo)) die_nomem(); + out("235 ok, go ahead (#2.0.0)\r\n"); + break; + case 1: + out("535 authorization failed (#5.7.0)\r\n"); + } +} + struct commands smtpcommands[] = { { "rcpt", smtp_rcpt, 0 } , { "mail", smtp_mail, 0 } , { "data", smtp_data, flush } +, { "auth", smtp_auth, flush } , { "quit", smtp_quit, flush } , { "helo", smtp_helo, flush } , { "ehlo", smtp_ehlo, flush } @@ -408,8 +644,13 @@ struct commands smtpcommands[] = { , { 0, err_unimpl, flush } } ; -void main() +void main(argc,argv) +int argc; +char **argv; { + hostname = argv[1]; + childargs = argv + 2; + sig_pipeignore(); if (chdir(auto_qmail) == -1) die_control(); setup(); |