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| -rw-r--r-- | smtp.c | 514 |
1 files changed, 514 insertions, 0 deletions
@@ -0,0 +1,514 @@ +/* Copyright 1996 Harry Hochheiser + * All rights reserved. + * For license terms, see the file COPYING in this directory. + */ + +/*********************************************************************** + module: smtp.c + project: popforward + programmer: Harry Hochheiser + description: Handling of SMTP connections, and processing of mail + to be forwarded via SMTP connections. + + 7/30/96. Note: since this file is new from scratch, I'll assume + that I'm working on a modern (ANSI) compiler, and I'll use + prototypes. + + + ***********************************************************************/ + +#include <config.h> +#include <sys/types.h> +#include <unistd.h> +#include <string.h> +#include "socket.h" +#include "popforward.h" +#include "smtp.h" + +static int POP3_parseHeaders(int number, int socket,char **from,int *replFlag); +static int SMTP_sendMessageHeaders(int mboxfd,struct optrec *option, + char *from); +static int SendData(int f,char *buf,int check); + + +/********************************************************************* + function: SMTP_helo + description: Send a "HELO" message to the SMTP server. + + arguments: + socket TCP/IP socket for connection to SMTP + return value: Result of SMTP_OK: based on codes in popforward.h. + + *********************************************************************/ + +int SMTP_helo(int socket,char *host) +{ + int ok; + char buf[SMTPBUFSIZE]; + sprintf(buf,"HELO %s\r\n",host); + SockPrintf(socket,"%s",buf); + ok = SMTP_ok(socket,buf); + return ok; +} + + +/********************************************************************* + function: SMTP_from + description: Send a "MAIL FROM:" message to the SMTP server. + + arguments: + socket TCP/IP socket for connection to SMTP + fromuser: user name of originator + fromhost: host name of originator. + + Note: these args are likely to change, as we get fancier about + handling the names. + + return value: Result of SMTP_ok: based on codes in popforward.h. + + *********************************************************************/ +int SMTP_from(int socket,char *fromuser,char *fromhost) +{ + char buf[SMTPBUFSIZE]; /* it's as good as size as any... */ + int ok; + SockPrintf(socket,"MAIL FROM %s@%s\n",fromuser,fromhost); + ok= SMTP_ok(socket,buf); + + return ok; +} + + +/********************************************************************* + function: SMTP_rcpt + description: Send a "RCPT TO:" message to the SMTP server. + + arguments: + socket TCP/IP socket for connection to SMTP + toser: user name of recipient + tohost: host name of recipient + + return value: Result of SMTP_OK: based on codes in popforward.h. + + *********************************************************************/ +int SMTP_rcpt(int socket,char *touser,char *tohost) +{ + char buf[SMTPBUFSIZE]; /* it's as good as size as any... */ + int ok; + + SockPrintf(socket,"RCPT TO: %s@%s\n",touser,tohost); + ok = SMTP_ok(socket,buf); + + return ok; +} + + +/********************************************************************* + function: SMTP_data + description: Send a "DATA" message to the SMTP server. + + arguments: + socket TCP/IP socket for connection to SMTP + + return value: Result of SMTP_OK: based on codes in popforward.h. + + *********************************************************************/ +int SMTP_data(int socket) +{ + SockPrintf(socket,"DATA\n"); +} + + +/********************************************************************* + function: SMTP_rset + description: Send a "DATA" message to the SMTP server. + + arguments: + socket TCP/IP socket for connection to SMTP + + return value: Result of SMTP_OK: based on codes in popforward.h. + + *********************************************************************/ +void SMTP_rset(int socket) +{ + SockPrintf(socket,"RSET\n"); +} + + + +/********************************************************************* + function: SMTP_check + description: Returns the status of the smtp connection + 8/13/96, HSH + arguments: + socket TCP/IP socket for connection to SMTP + + return value: based on codes in popforward.h. + Do the dirty work of seeing what the status is.. + *********************************************************************/ +static int SMTP_check(int socket,char *argbuf) +{ + int ok; + char buf[SMTPBUFSIZE]; + + if (SMTP_Gets(socket, buf, sizeof(buf)) > 0) { + if (argbuf) + strcpy(argbuf,buf); + if (buf[0] == '1' || buf[0] == '2' || buf[0] == '3') + ok = SM_OK; + else + ok = SM_ERROR; + } + else + ok= SM_UNRECOVERABLE; + return (ok); +} + +/********************************************************************* + function: SMTP_ok + description: Returns the statsus of the smtp connection + 7/31/96, HSH + arguments: + socket TCP/IP socket for connection to SMTP + + return value: based on codes in popforward.h. + + NOTE: As of 7/31/96 Initial implementation, we're just returning + a dummy value of SM_OK. Eventually, we should really implement this. + *********************************************************************/ +int SMTP_ok(int socket,char *argbuf) +{ + int ok; + char buf[SMTPBUFSIZE]; + + /* I can tell that the SMTP server connection is ok if I can read a + status message that starts with "1xx" ,"2xx" or "3xx". + Therefore, it can't be ok if there's no data waiting to be read + + Tried to deal with this with a call to SockDataWaiting, but + it failed badly. + + */ + + ok = SMTP_check(socket,argbuf); + if (ok == SM_ERROR) /* if we got an error, */ + { + SMTP_rset(socket); + ok = SMTP_check(socket,argbuf); /* how does it look now ? */ + if (ok == SM_OK) + ok = SM_ERROR; /* It's just a simple error, for*/ + /* the current message */ + else + ok = SM_UNRECOVERABLE; /* if It still says error, we're */ + /* in bad shape */ + } + return ok; +} + +/********************************************************************* + function: SMTP_Gets + description: Gets a line from the SMTP connection + 7/31/96, HSH + arguments: + socket TCP/IP socket for connection to SMTP + + return value: number of bytes read. + + *********************************************************************/ +int SMTP_Gets(int socket,char *buf,int sz) +{ + return read(socket,buf,sz); +} + + +/********************************************************************* + function: POP3_readSMTP + description: Read the message content as described in RFC 1225. + arguments: + number message number. + socket ... to which the server is connected. + mboxfd open file descriptor to which the retrieved message will + be written. + options added 7/30/96, HSH send in the whole options package... + server: originating pop server. 7/30/96, HSH + + This procedure is the SMTP version of the original POP3_readmsg that + is found in the original popforward. 8/2/96, HSH + return value: zero if success else PS_* return code. + calls: SockGets. + globals: reads outlevel. + *********************************************************************/ + +int POP3_readSMTP(int number,int socket,int mboxfd,struct optrec *options, + char *server) +{ + char buf [MSGBUFSIZE]; + char smtpbuf[SMTPBUFSIZE]; + char *bufp; + char fromBuf[MSGBUFSIZE]; + char *summaryHeaders[3]; + int sumLines =0; + int needFrom; + int inheaders; + int lines,sizeticker; + int n; + time_t now; + + char *from = NULL; + int replFlag = 0; + + + /* HSH 8/19/96, Archive file */ + + int archive = 0; + + int msgnum = 0; + + + /* This keeps the retrieved message count for display purposes */ + int ok=0; + + /* set up for status message if outlevel allows it */ + /* Get this into log file as well. */ + + + ok = POP3_parseHeaders(number,socket,&from,&replFlag); + if (ok != 0) + { + if (from) free(from); + return(PS_IOERR); + } + + ok = POP3_sendGet(number,options,socket); + if (ok != 0) + { + if (from) free(from); + return(PS_IOERR); + } + + /* 8/19/96 HSH open the archive file.. */ + + if ((archive =archGetFile(options,&msgnum)) <= 0) + { + if (from) free(from); + return(PS_IOERR); + } + + /* reads the message content from the server */ + inheaders = 1; + lines = 0; + sizeticker = MSGBUFSIZE; + while (1) { + if (SockGets(socket,buf,sizeof(buf)) < 0) + { + if (from) free(from); + return(PS_SOCKET); + } + bufp = buf; + if (buf[0] == '\r' || buf[0] == '\n') + inheaders = 0; + if (*bufp == '.') { + bufp++; + if (*bufp == 0) + break; /* end of message */ + } + strcat(bufp,"\n"); + + /* Check for Unix 'From' header, and add a bogus one if it's not + present -- only if not using an MDA. + XXX -- should probably parse real From: header and use its + address field instead of bogus 'POPmail' string. + */ + + + + if (lines == 0) { + if (strlen(bufp) >= strlen("From ")) + needFrom = strncasecmp(bufp,"From ",strlen("From ")); + else + needFrom = 1; + + if ((ok = SMTP_sendMessageHeaders(mboxfd,options,from)) != SM_OK) + goto smtperr; + + if (needFrom) { + now = time(NULL); + sprintf(fromBuf,"From POPmail %s",ctime(&now)); + if ((ok =SendData(mboxfd,fromBuf,0)) != SM_OK) + goto smtperr; + } + } + + n = write(archive,bufp,strlen(bufp)); + + /* write this line to the file */ + if ((ok =SendData(mboxfd,bufp,0)) != SM_OK) + { + /* Abort the message, so we'll be clear.. */ + SendData(mboxfd,BINMAIL_TERM,0); + goto smtperr; + } + + + sizeticker -= strlen(bufp); + lines++; + } + + if ((ok =SendData(mboxfd,BINMAIL_TERM,0)) !=SM_OK) + goto smtperr; + + + /* finish up display output */ + + if (from) free(from); + if (archive != 0) close(archive); + return(0); + +smtperr: + if (archive != 0) close(archive); + SMTP_rset(mboxfd); + if (from) free(from); + return(ok); +} + +/****************************************************************** + function: POP3_parseHeaders + description: Read the headers of the mail message, in order to grab the + "From" and "reply to" fields, to be used for proper + mail processing. + arguments: + number message number + socket TCP socket for POP connection + from character pointer to hold value of message "FROM" field + replFlag indicates whether or not we've seen a reply flag. + + ret. value: non-zero on success, else zero. + globals: SockGets POP3_OK. + calls: reads outlevel. + *****************************************************************/ +int POP3_parseHeaders(number,socket,from,replFlag) +int number; +int socket; +char **from; +int *replFlag; +{ + + int ok; + char buf[MSGBUFSIZE]; + char *bufp; + int len; + + ok = POP3_sendTOP(number,0,socket); + if (ok != 0) + return(ok); + + ok = -1; /* we're not ok until we find "FROM: " */ + /* read lines in until we're done.. */ + while (1) + { + + if (SockGets(socket,buf,sizeof(buf)) < 0) + { + return(PS_SOCKET); + } + bufp = buf; + + if (*bufp == '.') { + bufp++; + if (*bufp == 0) + break; /* end of message */ + } + + len = strlen(buf); + if (len < strlen(HEADER_FROM)) /* since From header is shorter than reply-to, it */ + continue; /* can't be either type. */ + + /* if it starts with "FROM: ", grab from */ + if (strncasecmp(buf,HEADER_FROM,strlen(HEADER_FROM)) == 0) + { + bufp = buf + strlen(HEADER_FROM); + *from = strdup(bufp); + ok =0; + } + if (strncasecmp(buf,HEADER_REPLY,strlen(HEADER_REPLY)) == 0) + *replFlag = 1; + } + + return(ok); +} + + +/****************************************************************** + function: SMTP_sendMessageHeaders + description: Send the headers for the smtp message along to the mailbox.. + arguments: + number message number + socket TCP socket for POP connection + from character pointer to hold value of message "FROM" field + replFlag indicates whether or not we've seen a reply flag. + + ret. value: non-zero on success, else zero. + globals: SockGets POP3_OK. + calls: reads outlevel. + *****************************************************************/ +int SMTP_sendMessageHeaders(int mboxfd,struct optrec *options,char *from) +{ + char smtpbuf[SMTPBUFSIZE]; + char fromBuf[MSGBUFSIZE]; + + int ok; + + /* 7/30/96, HSH add stuff to print out the SMTP commands. */ + ok = SMTP_ok(mboxfd,smtpbuf); + if (ok != SM_OK) + { + return ok; + } + /* mail is from whoever the headers said it was from */ + sprintf(fromBuf,"MAIL FROM: %s\r\n",from); + if ((ok = SendData(mboxfd,fromBuf,1)) != SM_OK) + return ok; + +/* Now here, add something for the receipt field. 7/30/96, + HSH */ + sprintf(fromBuf,"RCPT TO: %s@%s\r\n",options->forwarduser, + options->forwardhost); + if ((ok=SendData(mboxfd,fromBuf,1)) != SM_OK) + return ok; + + sprintf(fromBuf,"DATA\r\n"); + ok =SendData(mboxfd,fromBuf,1); + return ok; + +} + +/****************************************************************** + function: SendData + description: Write to socket or file, as appropriate for destination + arguments: + f socket or file descriptor + buf buffer to write + dest options destination. + check 1 if we should check for SMTP_ok, 0 if not... + ignored if DEST is not TO_SMTP + 7/30/96 HSH added + + ret. value: 0 if ok, otherwise, non-zero.. + globals: none. + calls: SockWrite + *****************************************************************/ + +static int SendData(int f,char *buf,int check) +{ + int res; + char smtpbuf[SMTPBUFSIZE]; + int len = strlen(buf); + + res = SockWrite(f,buf,len); + if (check != 0) + { + res = SMTP_ok(f,smtpbuf); + } + return res; +} + + |