/* * smtp.c -- code for speaking SMTP to a listener port * * Concept due to Harry Hochheiser. Implementation by ESR. Cleanup and * strict RFC821 compliance by Cameron MacPherson. * * Copyright 1997 Eric S. Raymond * For license terms, see the file COPYING in this directory. */ #include "config.h" #include "fetchmail.h" #include #include #include #include #include "socket.h" #include "smtp.h" #include "i18n.h" struct opt { const char *name; int value; }; static struct opt extensions[] = { {"8BITMIME", ESMTP_8BITMIME}, {"SIZE", ESMTP_SIZE}, {"ETRN", ESMTP_ETRN}, {"AUTH ", ESMTP_AUTH}, #ifdef ODMR_ENABLE {"ATRN", ESMTP_ATRN}, #endif /* ODMR_ENABLE */ {(char *)NULL, 0}, }; char smtp_response[MSGBUFSIZE]; int SMTP_helo(int sock, char smtp_mode, const char *host) /* send a "HELO" message to the SMTP listener */ { int ok; SockPrintf(sock,"HELO %s\r\n", host); if (outlevel >= O_MONITOR) report(stdout, "%cMTP> HELO %s\n", smtp_mode, host); ok = SMTP_ok(sock, smtp_mode); return ok; } static void SMTP_auth_error(int sock, const char *msg) { SockPrintf(sock, "*\r\n"); SockRead(sock, smtp_response, sizeof(smtp_response) - 1); if (outlevel >= O_MONITOR) report(stdout, msg); } static void SMTP_auth(int sock, char smtp_mode, char *username, char *password, char *buf) /* ESMTP Authentication support for fetchmail by Wojciech Polak */ { int c; char *p = 0; char b64buf[512]; char tmp[512]; if (!username || !password) return; memset(b64buf, 0, sizeof(b64buf)); memset(tmp, 0, sizeof(tmp)); if (strstr(buf, "CRAM-MD5")) { unsigned char digest[16]; memset(digest, 0, sizeof(digest)); if (outlevel >= O_MONITOR) report(stdout, GT_("ESMTP CRAM-MD5 Authentication...\n")); SockPrintf(sock, "AUTH CRAM-MD5\r\n"); SockRead(sock, smtp_response, sizeof(smtp_response) - 1); strncpy(tmp, smtp_response, sizeof(tmp)); tmp[sizeof(tmp)-1] = '\0'; if (strncmp(tmp, "334 ", 4)) { /* Server rejects AUTH */ SMTP_auth_error(sock, GT_("Server rejected the AUTH command.\n")); return; } p = strchr(tmp, ' '); p++; /* (hmh) from64tobits will not NULL-terminate strings! */ if (from64tobits(b64buf, p, sizeof(b64buf) - 1) <= 0) { SMTP_auth_error(sock, GT_("Bad base64 reply from server.\n")); return; } if (outlevel >= O_DEBUG) report(stdout, GT_("Challenge decoded: %s\n"), b64buf); hmac_md5(password, strlen(password), b64buf, strlen(b64buf), digest, sizeof(digest)); snprintf(tmp, sizeof(tmp), "%s %02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x", username, digest[0], digest[1], digest[2], digest[3], digest[4], digest[5], digest[6], digest[7], digest[8], digest[9], digest[10], digest[11], digest[12], digest[13], digest[14], digest[15]); to64frombits(b64buf, tmp, strlen(tmp)); SockPrintf(sock, "%s\r\n", b64buf); SMTP_ok(sock, smtp_mode); } else if (strstr(buf, "PLAIN")) { int len; if (outlevel >= O_MONITOR) report(stdout, GT_("ESMTP PLAIN Authentication...\n")); snprintf(tmp, sizeof(tmp), "^%s^%s", username, password); len = strlen(tmp); for (c = len - 1; c >= 0; c--) { if (tmp[c] == '^') tmp[c] = '\0'; } to64frombits(b64buf, tmp, len); SockPrintf(sock, "AUTH PLAIN %s\r\n", b64buf); SMTP_ok(sock, smtp_mode); } else if (strstr(buf, "LOGIN")) { if (outlevel >= O_MONITOR) report(stdout, GT_("ESMTP LOGIN Authentication...\n")); SockPrintf(sock, "AUTH LOGIN\r\n"); SockRead(sock, smtp_response, sizeof(smtp_response) - 1); strncpy(tmp, smtp_response, sizeof(tmp)); tmp[sizeof(tmp)-1] = '\0'; if (strncmp(tmp, "334 ", 4)) { /* Server rejects AUTH */ SMTP_auth_error(sock, GT_("Server rejected the AUTH command.\n")); return; } p = strchr(tmp, ' '); p++; if (from64tobits(b64buf, p, sizeof(b64buf) - 1) <= 0) { SMTP_auth_error(sock, GT_("Bad base64 reply from server.\n")); return; } to64frombits(b64buf, us
I maintain an open-source POP and IMAP client called fetchmail.  It is
widely used in the Linux and open-source community, and is probably
the single most popular remote-mail client in that world.  You can
find out more about this project at
<http://fetchmail.berlios.de/>.

In order to be able to do thorough regression testing before each release,
I collect test accounts on as many different kinds of POP3, IMAP, and
ODM