X-Git-Url: http://pileus.org/git/?a=blobdiff_plain;f=imap.c;h=65d225381b7c1b926c5d38d1e8312dbaf67c6ee2;hb=0aa3f030cdb0ab4a8e45360e6c1ec599d97e8acd;hp=df787da6208f7c10dbf362c47961cfc544539864;hpb=91edebd962aa90b42cb75b39064dd7e4e27841f1;p=~andy%2Ffetchmail diff --git a/imap.c b/imap.c index df787da6..65d22538 100644 --- a/imap.c +++ b/imap.c @@ -8,114 +8,222 @@ #include "config.h" #include #include +#include #include -#if defined(STDC_HEADERS) #include -#endif +#include +#include #include "fetchmail.h" #include "socket.h" -#ifdef KERBEROS_V4 -#ifdef KERBEROS_V5 -#include -#include -#else -#if defined (__bsdi__) -#include -#define krb_get_err_text(e) (krb_err_txt[e]) -#endif -#if defined(__NetBSD__) || (__FreeBSD__) || defined(__linux__) -#define krb_get_err_text(e) (krb_err_txt[e]) -#endif -#include -#endif -#endif /* KERBEROS_V4 */ -#include "i18n.h" - -#ifdef GSSAPI -#ifdef HAVE_GSSAPI_H -#include -#endif -#ifdef HAVE_GSSAPI_GSSAPI_H -#include -#endif -#ifdef HAVE_GSSAPI_GSSAPI_GENERIC_H -#include -#endif -#ifndef HAVE_GSS_C_NT_HOSTBASED_SERVICE -#define GSS_C_NT_HOSTBASED_SERVICE gss_nt_service_name -#endif -#endif - -#include "md5.h" - -#if OPIE_ENABLE -#include -#endif /* OPIE_ENABLE */ - -#ifndef strstr /* glibc-2.1 declares this as a macro */ -extern char *strstr(); /* needed on sysV68 R3V7.1. */ -#endif /* strstr */ +#include "gettext.h" /* imap_version values */ -#define IMAP2 -1 /* IMAP2 or IMAP2BIS, RFC1176 */ #define IMAP4 0 /* IMAP4 rev 0, RFC1730 */ #define IMAP4rev1 1 /* IMAP4 rev 1, RFC2060 */ -static int imap_phase; -#define PHASE_GETAUTH 0 -#define PHASE_GETRANGE 1 -#define PHASE_GETSIZES 2 -#define PHASE_FETCH 3 -#define PHASE_LOGOUT 4 +/* global variables: please reinitialize them explicitly for proper + * working in daemon mode */ + +/* TODO: session variables to be initialized before server greeting */ +static int preauth = FALSE; -static int count, seen, recent, unseen, deletions, imap_version, preauth; -static int expunged, expunge_period; +/* session variables initialized in capa_probe() or imap_getauth() */ static char capabilities[MSGBUFSIZE+1]; +static int imap_version = IMAP4; +static flag do_idle = FALSE, has_idle = FALSE; +static int expunge_period = 1; + +/* mailbox variables initialized in imap_getrange() */ +static int count = 0, oldcount = 0, recentcount = 0, unseen = 0, deletions = 0; +static unsigned int startcount = 1; +static int expunged = 0; +static unsigned int *unseen_messages; + +/* for "IMAP> EXPUNGE" */ +static int actual_deletions = 0; -int imap_ok(int sock, char *argbuf) +/* for "IMAP> IDLE" */ +static int saved_timeout = 0, idle_timeout = 0; +static time_t idle_start_time = 0; + +static int imap_untagged_response(int sock, const char *buf) +/* interpret untagged status responses */ +{ + /* For each individual check, use a BLANK before the word to avoid + * confusion with the \Recent flag or similar */ + if (stage == STAGE_GETAUTH + && !strncmp(buf, "* CAPABILITY", 12)) + { + strlcpy(capabilities, buf + 12, sizeof(capabilities)); + } + else if (stage == STAGE_GETAUTH + && !strncmp(buf, "* PREAUTH", 9)) + { + preauth = TRUE; + } + else if (stage != STAGE_LOGOUT + && !strncmp(buf, "* BYE", 5)) + { + /* log the unexpected bye from server as we expect the + * connection to be cut-off after this */ + if (outlevel > O_SILENT) + report(stderr, GT_("Received BYE response from IMAP server: %s"), buf + 5); + } + else if (strstr(buf, " EXISTS")) + { + char *t; unsigned long u; + errno = 0; + u = strtoul(buf+2, &t, 10); + /* + * Don't trust the message count passed by the server. + * Without this check, it might be possible to do a + * DNS-spoofing attack that would pass back a ridiculous + * count, and allocate a malloc area that would overlap + * a portion of the stack. + */ + if (errno /* strtoul failed */ + || t == buf+2 /* no valid data */ + || u > (unsigned long)(INT_MAX/sizeof(int)) /* too large */) + { + report(stderr, GT_("bogus message count in \"%s\"!"), buf); + return(PS_PROTOCOL); + } + count = u; /* safe as long as count <= INT_MAX - checked above */ + + if ((recentcount = count - oldcount) < 0) + recentcount = 0; + + /* + * Nasty kluge to handle RFC2177 IDLE. If we know we're idling + * we can't wait for the tag matching the IDLE; we have to tell the + * server the IDLE is finished by shipping back a DONE when we + * see an EXISTS. Only after that will a tagged response be + * shipped. The idling flag also gets cleared on a timeout. + */ + if (stage == STAGE_IDLE) + { + /* If IDLE isn't supported, we were only sending NOOPs anyway. */ + if (has_idle) + { + /* we do our own write and report here to disable tagging */ + SockWrite(sock, "DONE\r\n", 6); + if (outlevel >= O_MONITOR) + report(stdout, "IMAP> DONE\n"); + } + + mytimeout = saved_timeout; + stage = STAGE_GETRANGE; + } + } + /* we now compute recentcount as a difference between + * new and old EXISTS, hence disable RECENT check */ +# if 0 + else if (strstr(buf, " RECENT")) + { + /* fixme: use strto[u]l and error checking */ + recentcount = atoi(buf+2); + } +# endif + else if (strstr(buf, " EXPUNGE")) + { + unsigned long u; char *t; + /* the response "* 10 EXPUNGE" means that the currently + * tenth (i.e. only one) message has been deleted */ + errno = 0; + u = strtoul(buf+2, &t, 10); + if (errno /* conversion error */ || t == buf+2 /* no number found */) { + report(stderr, GT_("bogus EXPUNGE count in \"%s\"!"), buf); + return PS_PROTOCOL; + } + if (u > 0) + { + if (count > 0) + count--; + if (oldcount > 0) + oldcount--; + /* We do expect an EXISTS response immediately + * after this, so this updation of recentcount is + * just a precaution! */ + if ((recentcount = count - oldcount) < 0) + recentcount = 0; + actual_deletions++; + } + } + /* + * The server may decide to make the mailbox read-only, + * which causes fetchmail to go into a endless loop + * fetching the same message over and over again. + * + * However, for check_only, we use EXAMINE which will + * mark the mailbox read-only as per the RFC. + * + * This checks for the condition and aborts if + * the mailbox is read-only. + * + * See RFC 2060 section 6.3.1 (SELECT). + * See RFC 2060 section 6.3.2 (EXAMINE). + */ + else if (stage == STAGE_GETRANGE + && !check_only && strstr(buf, "[READ-ONLY]")) + { + return(PS_LOCKBUSY); + } + else + { + return(PS_UNTAGGED); + } + return(PS_SUCCESS); +} + +static int imap_response(int sock, char *argbuf, struct RecvSplit *rs) /* parse command response */ { - char buf [MSGBUFSIZE+1]; + char buf[MSGBUFSIZE+1]; - seen = 0; do { int ok; char *cp; - if ((ok = gen_recv(sock, buf, sizeof(buf)))) + if (rs) + ok = gen_recv_split(sock, buf, sizeof(buf), rs); + else + ok = gen_recv(sock, buf, sizeof(buf)); + if (ok != PS_SUCCESS) return(ok); /* all tokens in responses are caseblind */ for (cp = buf; *cp; cp++) - if (islower(*cp)) - *cp = toupper(*cp); - - /* interpret untagged status responses */ - if (strstr(buf, "* CAPABILITY")) - strncpy(capabilities, buf + 12, sizeof(capabilities)); - if (strstr(buf, "EXISTS")) - count = atoi(buf+2); - if (strstr(buf, "RECENT")) - recent = atoi(buf+2); - if (strstr(buf, "UNSEEN")) + if (islower((unsigned char)*cp)) + *cp = toupper((unsigned char)*cp); + + /* untagged responses start with "* " */ + if (buf[0] == '*' && buf[1] == ' ') { + ok = imap_untagged_response(sock, buf); + if (ok == PS_UNTAGGED) + { + if (argbuf && stage != STAGE_IDLE && tag[0] != '\0') + { + /* if there is an unmatched response, pass it back to + * the calling function for further analysis. The + * calling function should call imap_response() again + * to read the remaining response */ + strcpy(argbuf, buf); + return(ok); + } + } + else if (ok != PS_SUCCESS) + return(ok); + } + + if (stage == STAGE_IDLE) { - char *cp; - - /* - * Handle both "* 42 UNSEEN" (if tha ever happens) and - * "* OK [UNSEEN 42] 42". Note that what this gets us is - * a minimum index, not a count. - */ - unseen = 0; - for (cp = buf; *cp && !isdigit(*cp); cp++) - continue; - unseen = atoi(cp); + /* reduce the timeout: servers may not reset their timeout + * when they send some information asynchronously */ + mytimeout = idle_timeout - (time((time_t *) NULL) - idle_start_time); + if (mytimeout <= 0) + return(PS_IDLETIMEOUT); } - if (strstr(buf, "FLAGS")) - seen = (strstr(buf, "SEEN") != (char *)NULL); - if (strstr(buf, "PREAUTH")) - preauth = TRUE; } while (tag[0] != '\0' && strncmp(buf, tag, strlen(tag))); @@ -130,30 +238,25 @@ int imap_ok(int sock, char *argbuf) char *cp; /* skip the tag */ - for (cp = buf; !isspace(*cp); cp++) + for (cp = buf; !isspace((unsigned char)*cp); cp++) continue; - while (isspace(*cp)) + while (isspace((unsigned char)*cp)) cp++; - if (strncmp(cp, "PREAUTH", 2) == 0) - { - if (argbuf) - strcpy(argbuf, cp); - preauth = TRUE; - return(PS_SUCCESS); - } - else if (strncmp(cp, "OK", 2) == 0) + if (strncasecmp(cp, "OK", 2) == 0) { if (argbuf) strcpy(argbuf, cp); return(PS_SUCCESS); } - else if (strncmp(cp, "BAD", 3) == 0) + else if (strncasecmp(cp, "BAD", 3) == 0) return(PS_ERROR); - else if (strncmp(cp, "NO", 2) == 0) + else if (strncasecmp(cp, "NO", 2) == 0) { - if (imap_phase == PHASE_GETAUTH) + if (stage == STAGE_GETAUTH) return(PS_AUTHFAIL); /* RFC2060, 6.2.2 */ + else if (stage == STAGE_GETSIZES) + return(PS_SUCCESS); /* see comments in imap_getpartialsizes() */ else return(PS_ERROR); } @@ -162,531 +265,19 @@ int imap_ok(int sock, char *argbuf) } } -#if OPIE_ENABLE -static int do_otp(int sock, struct query *ctl) -{ - int i, rval; - char buffer[128]; - char challenge[OPIE_CHALLENGE_MAX+1]; - char response[OPIE_RESPONSE_MAX+1]; - - gen_send(sock, "AUTHENTICATE X-OTP"); - - if (rval = gen_recv(sock, buffer, sizeof(buffer))) - return rval; - - if ((i = from64tobits(challenge, buffer)) < 0) { - report(stderr, _("Could not decode initial BASE64 challenge\n")); - return PS_AUTHFAIL; - }; - - - to64frombits(buffer, ctl->remotename, strlen(ctl->remotename)); - - if (outlevel >= O_MONITOR) - report(stdout, "IMAP> %s\n", buffer); - - /* best not to count on the challenge code handling multiple writes */ - strcat(buffer, "\r\n"); - SockWrite(sock, buffer, strlen(buffer)); - - if (rval = gen_recv(sock, buffer, sizeof(buffer))) - return rval; - - if ((i = from64tobits(challenge, buffer)) < 0) { - report(stderr, _("Could not decode OTP challenge\n")); - return PS_AUTHFAIL; - }; - - rval = opiegenerator(challenge, !strcmp(ctl->password, "opie") ? "" : ctl->password, response); - if ((rval == -2) && !run.poll_interval) { - char secret[OPIE_SECRET_MAX+1]; - fprintf(stderr, _("Secret pass phrase: ")); - if (opiereadpass(secret, sizeof(secret), 0)) - rval = opiegenerator(challenge, secret, response); - memset(secret, 0, sizeof(secret)); - }; - - if (rval) - return(PS_AUTHFAIL); - - to64frombits(buffer, response, strlen(response)); - - if (outlevel >= O_MONITOR) - report(stdout, "IMAP> %s\n", buffer); - strcat(buffer, "\r\n"); - SockWrite(sock, buffer, strlen(buffer)); - - if (rval = gen_recv(sock, buffer, sizeof(buffer))) - return rval; - - if (strstr(buffer, "OK")) - return PS_SUCCESS; - else - return PS_AUTHFAIL; -}; -#endif /* OPIE_ENABLE */ - -#ifdef KERBEROS_V4 -#if SIZEOF_INT == 4 -typedef int int32; -#elif SIZEOF_SHORT == 4 -typedef short int32; -#elif SIZEOF_LONG == 4 -typedef long int32; -#else -#error Cannot deduce a 32-bit-type -#endif - -static int do_rfc1731(int sock, char *truename) -/* authenticate as per RFC1731 -- note 32-bit integer requirement here */ -{ - int result = 0, len; - char buf1[4096], buf2[4096]; - union { - int32 cint; - char cstr[4]; - } challenge1, challenge2; - char srvinst[INST_SZ]; - char *p; - char srvrealm[REALM_SZ]; - KTEXT_ST authenticator; - CREDENTIALS credentials; - char tktuser[MAX_K_NAME_SZ+1+INST_SZ+1+REALM_SZ+1]; - char tktinst[INST_SZ]; - char tktrealm[REALM_SZ]; - des_cblock session; - des_key_schedule schedule; - - gen_send(sock, "AUTHENTICATE KERBEROS_V4"); - - /* The data encoded in the first ready response contains a random - * 32-bit number in network byte order. The client should respond - * with a Kerberos ticket and an authenticator for the principal - * "imap.hostname@realm", where "hostname" is the first component - * of the host name of the server with all letters in lower case - * and where "realm" is the Kerberos realm of the server. The - * encrypted checksum field included within the Kerberos - * authenticator should contain the server provided 32-bit number - * in network byte order. - */ - - if (result = gen_recv(sock, buf1, sizeof buf1)) { - return result; - } - - len = from64tobits(challenge1.cstr, buf1); - if (len < 0) { - report(stderr, _("could not decode initial BASE64 challenge\n")); - return PS_AUTHFAIL; - } - - /* this patch by Dan Root solves an endianess - * problem. */ - { - char tmp[4]; - - *(int *)tmp = ntohl(*(int *) challenge1.cstr); - memcpy(challenge1.cstr, tmp, sizeof(tmp)); - } - - /* Client responds with a Kerberos ticket and an authenticator for - * the principal "imap.hostname@realm" where "hostname" is the - * first component of the host name of the server with all letters - * in lower case and where "realm" is the Kerberos realm of the - * server. The encrypted checksum field included within the - * Kerberos authenticator should contain the server-provided - * 32-bit number in network byte order. - */ - - strncpy(srvinst, truename, (sizeof srvinst)-1); - srvinst[(sizeof srvinst)-1] = '\0'; - for (p = srvinst; *p; p++) { - if (isupper(*p)) { - *p = tolower(*p); - } - } - - strncpy(srvrealm, (char *)krb_realmofhost(srvinst), (sizeof srvrealm)-1); - srvrealm[(sizeof srvrealm)-1] = '\0'; - if (p = strchr(srvinst, '.')) { - *p = '\0'; - } - - result = krb_mk_req(&authenticator, "imap", srvinst, srvrealm, 0); - if (result) { - report(stderr, "krb_mq_req: %s\n", krb_get_err_text(result)); - return PS_AUTHFAIL; - } - - result = krb_get_cred("imap", srvinst, srvrealm, &credentials); - if (result) { - report(stderr, "krb_get_cred: %s\n", krb_get_err_text(result)); - return PS_AUTHFAIL; - } - - memcpy(session, credentials.session, sizeof session); - memset(&credentials, 0, sizeof credentials); - des_key_sched(&session, schedule); - - result = krb_get_tf_fullname(TKT_FILE, tktuser, tktinst, tktrealm); - if (result) { - report(stderr, "krb_get_tf_fullname: %s\n", krb_get_err_text(result)); - return PS_AUTHFAIL; - } - - if (strcmp(tktuser, user) != 0) { - report(stderr, - _("principal %s in ticket does not match -u %s\n"), tktuser, - user); - return PS_AUTHFAIL; - } - - if (tktinst[0]) { - report(stderr, - _("non-null instance (%s) might cause strange behavior\n"), - tktinst); - strcat(tktuser, "."); - strcat(tktuser, tktinst); - } - - if (strcmp(tktrealm, srvrealm) != 0) { - strcat(tktuser, "@"); - strcat(tktuser, tktrealm); - } - - result = krb_mk_req(&authenticator, "imap", srvinst, srvrealm, - challenge1.cint); - if (result) { - report(stderr, "krb_mq_req: %s\n", krb_get_err_text(result)); - return PS_AUTHFAIL; - } - - to64frombits(buf1, authenticator.dat, authenticator.length); - if (outlevel >= O_MONITOR) { - report(stdout, "IMAP> %s\n", buf1); - } - strcat(buf1, "\r\n"); - SockWrite(sock, buf1, strlen(buf1)); - - /* Upon decrypting and verifying the ticket and authenticator, the - * server should verify that the contained checksum field equals - * the original server provided random 32-bit number. Should the - * verification be successful, the server must add one to the - * checksum and construct 8 octets of data, with the first four - * octets containing the incremented checksum in network byte - * order, the fifth octet containing a bit-mask specifying the - * protection mechanisms supported by the server, and the sixth - * through eighth octets containing, in network byte order, the - * maximum cipher-text buffer size the server is able to receive. - * The server must encrypt the 8 octets of data in the session key - * and issue that encrypted data in a second ready response. The - * client should consider the server authenticated if the first - * four octets the un-encrypted data is equal to one plus the - * checksum it previously sent. - */ - - if (result = gen_recv(sock, buf1, sizeof buf1)) - return result; - - /* The client must construct data with the first four octets - * containing the original server-issued checksum in network byte - * order, the fifth octet containing the bit-mask specifying the - * selected protection mechanism, the sixth through eighth octets - * containing in network byte order the maximum cipher-text buffer - * size the client is able to receive, and the following octets - * containing a user name string. The client must then append - * from one to eight octets so that the length of the data is a - * multiple of eight octets. The client must then PCBC encrypt the - * data with the session key and respond to the second ready - * response with the encrypted data. The server decrypts the data - * and verifies the contained checksum. The username field - * identifies the user for whom subsequent IMAP operations are to - * be performed; the server must verify that the principal - * identified in the Kerberos ticket is authorized to connect as - * that user. After these verifications, the authentication - * process is complete. - */ - - len = from64tobits(buf2, buf1); - if (len < 0) { - report(stderr, _("could not decode BASE64 ready response\n")); - return PS_AUTHFAIL; - } - - des_ecb_encrypt((des_cblock *)buf2, (des_cblock *)buf2, schedule, 0); - memcpy(challenge2.cstr, buf2, 4); - if (ntohl(challenge2.cint) != challenge1.cint + 1) { - report(stderr, _("challenge mismatch\n")); - return PS_AUTHFAIL; - } - - memset(authenticator.dat, 0, sizeof authenticator.dat); - - result = htonl(challenge1.cint); - memcpy(authenticator.dat, &result, sizeof result); - - /* The protection mechanisms and their corresponding bit-masks are as - * follows: - * - * 1 No protection mechanism - * 2 Integrity (krb_mk_safe) protection - * 4 Privacy (krb_mk_priv) protection - */ - authenticator.dat[4] = 1; - - len = strlen(tktuser); - strncpy(authenticator.dat+8, tktuser, len); - authenticator.length = len + 8 + 1; - while (authenticator.length & 7) { - authenticator.length++; - } - des_pcbc_encrypt((des_cblock *)authenticator.dat, - (des_cblock *)authenticator.dat, authenticator.length, schedule, - &session, 1); - - to64frombits(buf1, authenticator.dat, authenticator.length); - if (outlevel >= O_MONITOR) { - report(stdout, "IMAP> %s\n", buf1); - } - - strcat(buf1, "\r\n"); - SockWrite(sock, buf1, strlen(buf1)); - - if (result = gen_recv(sock, buf1, sizeof buf1)) - return result; - - if (strstr(buf1, "OK")) { - return PS_SUCCESS; - } - else { - return PS_AUTHFAIL; - } -} -#endif /* KERBEROS_V4 */ - -#ifdef GSSAPI -#define GSSAUTH_P_NONE 1 -#define GSSAUTH_P_INTEGRITY 2 -#define GSSAUTH_P_PRIVACY 4 - -static int do_gssauth(int sock, char *hostname, char *username) -{ - gss_buffer_desc request_buf, send_token; - gss_buffer_t sec_token; - gss_name_t target_name; - gss_ctx_id_t context; - gss_OID mech_name; - gss_qop_t quality; - int cflags; - OM_uint32 maj_stat, min_stat; - char buf1[8192], buf2[8192], server_conf_flags; - unsigned long buf_size; - int result; - - /* first things first: get an imap ticket for host */ - sprintf(buf1, "imap@%s", hostname); - request_buf.value = buf1; - request_buf.length = strlen(buf1) + 1; - maj_stat = gss_import_name(&min_stat, &request_buf, GSS_C_NT_HOSTBASED_SERVICE, - &target_name); - if (maj_stat != GSS_S_COMPLETE) { - report(stderr, _("Couldn't get service name for [%s]\n"), buf1); - return PS_AUTHFAIL; - } - else if (outlevel >= O_DEBUG) { - maj_stat = gss_display_name(&min_stat, target_name, &request_buf, - &mech_name); - report(stderr, _("Using service name [%s]\n"),request_buf.value); - maj_stat = gss_release_buffer(&min_stat, &request_buf); - } - - gen_send(sock, "AUTHENTICATE GSSAPI"); - - /* upon receipt of the GSSAPI authentication request, server returns - * null data ready response. */ - if (result = gen_recv(sock, buf1, sizeof buf1)) { - return result; - } - - /* now start the security context initialisation loop... */ - sec_token = GSS_C_NO_BUFFER; - context = GSS_C_NO_CONTEXT; - if (outlevel >= O_VERBOSE) - report(stdout, _("Sending credentials\n")); - do { - send_token.length = 0; - send_token.value = NULL; - maj_stat = gss_init_sec_context(&min_stat, - GSS_C_NO_CREDENTIAL, - &context, - target_name, - GSS_C_NO_OID, - GSS_C_MUTUAL_FLAG | GSS_C_SEQUENCE_FLAG, - 0, - GSS_C_NO_CHANNEL_BINDINGS, - sec_token, - NULL, - &send_token, - NULL, - NULL); - if (maj_stat!=GSS_S_COMPLETE && maj_stat!=GSS_S_CONTINUE_NEEDED) { - report(stderr, _("Error exchanging credentials\n")); - gss_release_name(&min_stat, &target_name); - /* wake up server and await NO response */ - SockWrite(sock, "\r\n", 2); - if (result = gen_recv(sock, buf1, sizeof buf1)) - return result; - return PS_AUTHFAIL; - } - to64frombits(buf1, send_token.value, send_token.length); - gss_release_buffer(&min_stat, &send_token); - strcat(buf1, "\r\n"); - SockWrite(sock, buf1, strlen(buf1)); - if (outlevel >= O_MONITOR) - report(stdout, "IMAP> %s\n", buf1); - if (maj_stat == GSS_S_CONTINUE_NEEDED) { - if (result = gen_recv(sock, buf1, sizeof buf1)) { - gss_release_name(&min_stat, &target_name); - return result; - } - request_buf.length = from64tobits(buf2, buf1 + 2); - request_buf.value = buf2; - sec_token = &request_buf; - } - } while (maj_stat == GSS_S_CONTINUE_NEEDED); - gss_release_name(&min_stat, &target_name); - - /* get security flags and buffer size */ - if (result = gen_recv(sock, buf1, sizeof buf1)) { - return result; - } - request_buf.length = from64tobits(buf2, buf1 + 2); - request_buf.value = buf2; - - maj_stat = gss_unwrap(&min_stat, context, &request_buf, &send_token, - &cflags, &quality); - if (maj_stat != GSS_S_COMPLETE) { - report(stderr, _("Couldn't unwrap security level data\n")); - gss_release_buffer(&min_stat, &send_token); - return PS_AUTHFAIL; - } - if (outlevel >= O_DEBUG) - report(stdout, _("Credential exchange complete\n")); - /* first octet is security levels supported. We want none, for now */ - server_conf_flags = ((char *)send_token.value)[0]; - if ( !(((char *)send_token.value)[0] & GSSAUTH_P_NONE) ) { - report(stderr, _("Server requires integrity and/or privacy\n")); - gss_release_buffer(&min_stat, &send_token); - return PS_AUTHFAIL; - } - ((char *)send_token.value)[0] = 0; - buf_size = ntohl(*((long *)send_token.value)); - /* we don't care about buffer size if we don't wrap data */ - gss_release_buffer(&min_stat, &send_token); - if (outlevel >= O_DEBUG) { - report(stdout, _("Unwrapped security level flags: %s%s%s\n"), - server_conf_flags & GSSAUTH_P_NONE ? "N" : "-", - server_conf_flags & GSSAUTH_P_INTEGRITY ? "I" : "-", - server_conf_flags & GSSAUTH_P_PRIVACY ? "C" : "-"); - report(stdout, _("Maximum GSS token size is %ld\n"),buf_size); - } - - /* now respond in kind (hack!!!) */ - buf_size = htonl(buf_size); /* do as they do... only matters if we do enc */ - memcpy(buf1, &buf_size, 4); - buf1[0] = GSSAUTH_P_NONE; - strcpy(buf1+4, username); /* server decides if princ is user */ - request_buf.length = 4 + strlen(username) + 1; - request_buf.value = buf1; - maj_stat = gss_wrap(&min_stat, context, 0, GSS_C_QOP_DEFAULT, &request_buf, - &cflags, &send_token); - if (maj_stat != GSS_S_COMPLETE) { - report(stderr, _("Error creating security level request\n")); - return PS_AUTHFAIL; - } - to64frombits(buf1, send_token.value, send_token.length); - if (outlevel >= O_DEBUG) { - report(stdout, _("Requesting authorization as %s\n"), username); - report(stdout, "IMAP> %s\n",buf1); - } - strcat(buf1, "\r\n"); - SockWrite(sock, buf1, strlen(buf1)); - - /* we should be done. Get status and finish up */ - if (result = gen_recv(sock, buf1, sizeof buf1)) - return result; - if (strstr(buf1, "OK")) { - /* flush security context */ - if (outlevel >= O_DEBUG) - report(stdout, _("Releasing GSS credentials\n")); - maj_stat = gss_delete_sec_context(&min_stat, &context, &send_token); - if (maj_stat != GSS_S_COMPLETE) { - report(stderr, _("Error releasing credentials\n")); - return PS_AUTHFAIL; - } - /* send_token may contain a notification to the server to flush - * credentials. RFC 1731 doesn't specify what to do, and since this - * support is only for authentication, we'll assume the server - * knows enough to flush its own credentials */ - gss_release_buffer(&min_stat, &send_token); - return PS_SUCCESS; - } - - return PS_AUTHFAIL; -} -#endif /* GSSAPI */ - -static void hmac_md5 (unsigned char *password, size_t pass_len, - unsigned char *challenge, size_t chal_len, - unsigned char *response, size_t resp_len) +static int imap_ok(int sock, char *argbuf) +/* parse command response */ { - int i; - unsigned char ipad[64]; - unsigned char opad[64]; - unsigned char hash_passwd[16]; - - MD5_CTX ctx; - - if (resp_len != 16) - return; - - if (pass_len > sizeof (ipad)) - { - MD5Init (&ctx); - MD5Update (&ctx, password, pass_len); - MD5Final (hash_passwd, &ctx); - password = hash_passwd; pass_len = sizeof (hash_passwd); - } - - memset (ipad, 0, sizeof (ipad)); - memset (opad, 0, sizeof (opad)); - memcpy (ipad, password, pass_len); - memcpy (opad, password, pass_len); - - for (i=0; i<64; i++) { - ipad[i] ^= 0x36; - opad[i] ^= 0x5c; - } - - MD5Init (&ctx); - MD5Update (&ctx, ipad, sizeof (ipad)); - MD5Update (&ctx, challenge, chal_len); - MD5Final (response, &ctx); + int ok; - MD5Init (&ctx); - MD5Update (&ctx, opad, sizeof (opad)); - MD5Update (&ctx, response, resp_len); - MD5Final (response, &ctx); + while ((ok = imap_response(sock, argbuf, NULL)) == PS_UNTAGGED) + ; /* wait for the tagged response */ + return(ok); } -#if NTLM_ENABLE +#ifdef NTLM_ENABLE #include "ntlm.h" -static tSmbNtlmAuthRequest request; -static tSmbNtlmAuthChallenge challenge; -static tSmbNtlmAuthResponse response; - /* * NTLM support by Grant Edwards. * @@ -700,151 +291,25 @@ static tSmbNtlmAuthResponse response; static int do_imap_ntlm(int sock, struct query *ctl) { - char msgbuf[2048]; - int result,len; - + int result; + gen_send(sock, "AUTHENTICATE NTLM"); - if ((result = gen_recv(sock, msgbuf, sizeof msgbuf))) + if ((result = ntlm_helper(sock, ctl, "IMAP"))) return result; - - if (msgbuf[0] != '+') - return PS_AUTHFAIL; - - buildSmbNtlmAuthRequest(&request,ctl->remotename,NULL); - - if (outlevel >= O_DEBUG) - dumpSmbNtlmAuthRequest(stdout, &request); - - memset(msgbuf,0,sizeof msgbuf); - to64frombits (msgbuf, (unsigned char*)&request, SmbLength(&request)); - - if (outlevel >= O_MONITOR) - report(stdout, "IMAP> %s\n", msgbuf); - - strcat(msgbuf,"\r\n"); - SockWrite (sock, msgbuf, strlen (msgbuf)); - - if ((gen_recv(sock, msgbuf, sizeof msgbuf))) - return result; - - len = from64tobits ((unsigned char*)&challenge, msgbuf); - - if (outlevel >= O_DEBUG) - dumpSmbNtlmAuthChallenge(stdout, &challenge); - - buildSmbNtlmAuthResponse(&challenge, &response,ctl->remotename,ctl->password); - - if (outlevel >= O_DEBUG) - dumpSmbNtlmAuthResponse(stdout, &response); - - memset(msgbuf,0,sizeof msgbuf); - to64frombits (msgbuf, (unsigned char*)&response, SmbLength(&response)); - - if (outlevel >= O_MONITOR) - report(stdout, "IMAP> %s\n", msgbuf); - - strcat(msgbuf,"\r\n"); - - SockWrite (sock, msgbuf, strlen (msgbuf)); - - if ((result = gen_recv (sock, msgbuf, sizeof msgbuf))) - return result; - - if (strstr (msgbuf, "OK")) + + result = imap_ok (sock, NULL); + if (result == PS_SUCCESS) return PS_SUCCESS; else return PS_AUTHFAIL; } #endif /* NTLM */ -static int do_cram_md5 (int sock, struct query *ctl) -/* authenticate as per RFC2195 */ -{ - int result; - int len; - unsigned char buf1[1024]; - unsigned char msg_id[768]; - unsigned char response[16]; - unsigned char reply[1024]; - - gen_send (sock, "AUTHENTICATE CRAM-MD5"); - - /* From RFC2195: - * The data encoded in the first ready response contains an - * presumptively arbitrary string of random digits, a timestamp, and the - * fully-qualified primary host name of the server. The syntax of the - * unencoded form must correspond to that of an RFC 822 'msg-id' - * [RFC822] as described in [POP3]. - */ - - if ((result = gen_recv (sock, buf1, sizeof (buf1)))) { - return result; - } - - len = from64tobits (msg_id, buf1); - if (len < 0) { - report (stderr, _("could not decode BASE64 challenge\n")); - return PS_AUTHFAIL; - } else if (len < sizeof (msg_id)) { - msg_id[len] = 0; - } else { - msg_id[sizeof (msg_id)-1] = 0; - } - if (outlevel >= O_DEBUG) { - report (stdout, "decoded as %s\n", msg_id); - } - - /* The client makes note of the data and then responds with a string - * consisting of the user name, a space, and a 'digest'. The latter is - * computed by applying the keyed MD5 algorithm from [KEYED-MD5] where - * the key is a shared secret and the digested text is the timestamp - * (including angle-brackets). - */ - - hmac_md5 (ctl->password, strlen (ctl->password), - msg_id, strlen (msg_id), - response, sizeof (response)); - -#ifdef HAVE_SNPRINTF - snprintf (reply, sizeof (reply), -#else - sprintf(reply, -#endif - "%s %02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x", - ctl->remotename, - response[0], response[1], response[2], response[3], - response[4], response[5], response[6], response[7], - response[8], response[9], response[10], response[11], - response[12], response[13], response[14], response[15]); - - if (outlevel >= O_DEBUG) { - report (stdout, "replying with %s\n", reply); - } - - to64frombits (buf1, reply, strlen (reply)); - if (outlevel >= O_MONITOR) { - report (stdout, "IMAP> %s\n", buf1); - } - - /* PMDF5.2 IMAP has a bug that requires this to be a single write */ - strcat (buf1, "\r\n"); - SockWrite (sock, buf1, strlen (buf1)); - - if ((result = gen_recv (sock, buf1, sizeof (buf1)))) - return result; - - if (strstr (buf1, "OK")) { - return PS_SUCCESS; - } else { - return PS_AUTHFAIL; - } -} - -int imap_canonicalize(char *result, char *raw, int maxlen) +static void imap_canonicalize(char *result, char *raw, size_t maxlen) /* encode an IMAP password as per RFC1730's quoting conventions */ { - int i, j; + size_t i, j; j = 0; for (i = 0; i < strlen(raw) && i < maxlen; i++) @@ -854,166 +319,317 @@ int imap_canonicalize(char *result, char *raw, int maxlen) result[j++] = raw[i]; } result[j] = '\0'; - - return(i); } -int imap_getauth(int sock, struct query *ctl, char *greeting) -/* apply for connection authorization */ +static int capa_probe(int sock, struct query *ctl) +/* set capability variables from a CAPA probe */ { - int ok = 0; - - imap_phase = PHASE_GETAUTH; + int ok; /* probe to see if we're running IMAP4 and can use RFC822.PEEK */ capabilities[0] = '\0'; if ((ok = gen_transact(sock, "CAPABILITY")) == PS_SUCCESS) { - /* UW-IMAP server 10.173 notifies in all caps */ + char *cp; + + /* capability checks are supposed to be caseblind */ + for (cp = capabilities; *cp; cp++) + *cp = toupper((unsigned char)*cp); + + /* UW-IMAP server 10.173 notifies in all caps, but RFC2060 says we + should expect a response in mixed-case */ if (strstr(capabilities, "IMAP4REV1")) { imap_version = IMAP4rev1; if (outlevel >= O_DEBUG) - report(stdout, _("Protocol identified as IMAP4 rev 1\n")); + report(stdout, GT_("Protocol identified as IMAP4 rev 1\n")); } else { imap_version = IMAP4; if (outlevel >= O_DEBUG) - report(stdout, _("Protocol identified as IMAP4 rev 0\n")); + report(stdout, GT_("Protocol identified as IMAP4 rev 0\n")); } } - else if (ok == PS_ERROR) + else + return ok; + + /* + * Handle idling. We depend on coming through here on startup + * and after each timeout (including timeouts during idles). + */ + do_idle = ctl->idle; + if (ctl->idle) { - imap_version = IMAP2; - if (outlevel >= O_DEBUG) - report(stdout, _("Protocol identified as IMAP2 or IMAP2BIS\n")); + if (strstr(capabilities, "IDLE")) + has_idle = TRUE; + else + has_idle = FALSE; + if (outlevel >= O_VERBOSE) + report(stdout, GT_("will idle after poll\n")); + } + + peek_capable = TRUE; + + return PS_SUCCESS; +} + +static int do_authcert (int sock, const char *command, const char *name) +/* do authentication "external" (authentication provided by client cert) */ +{ + char buf[256]; + + if (name && name[0]) + { + size_t len = strlen(name); + if ((len / 3) + ((len % 3) ? 4 : 0) < sizeof(buf)) + to64frombits (buf, name, strlen(name)); + else + return PS_AUTHFAIL; /* buffer too small. */ } else - return(ok); + buf[0]=0; + return gen_transact(sock, "%s EXTERNAL %s",command,buf); +} + +static int imap_getauth(int sock, struct query *ctl, char *greeting) +/* apply for connection authorization */ +{ + int ok = 0; + (void)greeting; + + /* + * Assumption: expunges are cheap, so we want to do them + * after every message unless user said otherwise. + */ + if (NUM_SPECIFIED(ctl->expunge)) + expunge_period = NUM_VALUE_OUT(ctl->expunge); + else + expunge_period = 1; + + if ((ok = capa_probe(sock, ctl))) + return ok; + + /* + * If either (a) we saw a PREAUTH token in the greeting, or + * (b) the user specified ssh preauthentication, then we're done. + */ + if (preauth || ctl->server.authenticate == A_SSH) + { + preauth = FALSE; /* reset for the next session */ + return(PS_SUCCESS); + } + +#ifdef SSL_ENABLE + if (maybe_tls(ctl)) { + char *commonname; + + commonname = ctl->server.pollname; + if (ctl->server.via) + commonname = ctl->server.via; + if (ctl->sslcommonname) + commonname = ctl->sslcommonname; - peek_capable = (imap_version >= IMAP4); + if (strstr(capabilities, "STARTTLS") + || must_tls(ctl)) /* if TLS is mandatory, ignore capabilities */ + { + /* Use "tls1" rather than ctl->sslproto because tls1 is the only + * protocol that will work with STARTTLS. Don't need to worry + * whether TLS is mandatory or opportunistic unless SSLOpen() fails + * (see below). */ + if (gen_transact(sock, "STARTTLS") == PS_SUCCESS + && (set_timeout(mytimeout), SSLOpen(sock, ctl->sslcert, ctl->sslkey, "tls1", ctl->sslcertck, + ctl->sslcertfile, ctl->sslcertpath, ctl->sslfingerprint, commonname, + ctl->server.pollname, &ctl->remotename)) != -1) + { + /* + * RFC 2595 says this: + * + * "Once TLS has been started, the client MUST discard cached + * information about server capabilities and SHOULD re-issue the + * CAPABILITY command. This is necessary to protect against + * man-in-the-middle attacks which alter the capabilities list prior + * to STARTTLS. The server MAY advertise different capabilities + * after STARTTLS." + * + * Now that we're confident in our TLS connection we can + * guarantee a secure capability re-probe. + */ + if ((ok = capa_probe(sock, ctl))) + return ok; + if (outlevel >= O_VERBOSE) + { + report(stdout, GT_("%s: upgrade to TLS succeeded.\n"), commonname); + } + } else if (must_tls(ctl)) { + /* Config required TLS but we couldn't guarantee it, so we must + * stop. */ + set_timeout(0); + report(stderr, GT_("%s: upgrade to TLS failed.\n"), commonname); + return PS_SOCKET; + } else { + set_timeout(0); + if (outlevel >= O_VERBOSE) { + report(stdout, GT_("%s: opportunistic upgrade to TLS failed, trying to continue\n"), commonname); + } + /* We don't know whether the connection is in a working state, so + * test by issuing a NOOP. */ + if (gen_transact(sock, "NOOP") != PS_SUCCESS) { + /* Not usable. Empty sslproto to force an unencrypted + * connection on the next attempt, and repoll. */ + ctl->sslproto = xstrdup(""); + return PS_REPOLL; + } + /* Usable. Proceed with authenticating insecurely. */ + } + } + } +#endif /* SSL_ENABLE */ - /* - * Assumption: expunges are cheap, so we want to do them - * after every message unless user said otherwise. + /* + * Time to authenticate the user. + * Try the protocol variants that don't require passwords first. */ - if (NUM_SPECIFIED(ctl->expunge)) - expunge_period = NUM_VALUE_OUT(ctl->expunge); - else - expunge_period = 1; - - if (preauth) - return(PS_SUCCESS); + ok = PS_AUTHFAIL; -#if OPIE_ENABLE - if ((ctl->server.protocol == P_IMAP) && strstr(capabilities, "AUTH=X-OTP")) + /* Yahoo hack - we'll just try ID if it was offered by the server, + * and IGNORE errors. */ { - if (outlevel >= O_DEBUG) - report(stdout, _("OTP authentication is supported\n")); - if (do_otp(sock, ctl) == PS_SUCCESS) - return(PS_SUCCESS); - }; -#endif /* OPIE_ENABLE */ + char *tmp = strstr(capabilities, " ID"); + if (tmp && !isalnum((unsigned char)tmp[3]) && strstr(ctl->server.via ? ctl->server.via : ctl->server.pollname, "yahoo.com")) { + (void)gen_transact(sock, "ID (\"guid\" \"1\")"); + } + } -#ifdef GSSAPI - if (strstr(capabilities, "AUTH=GSSAPI")) + if ((ctl->server.authenticate == A_ANY + || ctl->server.authenticate == A_EXTERNAL) + && strstr(capabilities, "AUTH=EXTERNAL")) { - if (ctl->server.protocol == P_IMAP_GSS) + ok = do_authcert(sock, "AUTHENTICATE", ctl->remotename); + if (ok) { - if (outlevel >= O_DEBUG) - report(stdout, _("GSS authentication is supported\n")); - return do_gssauth(sock, ctl->server.truename, ctl->remotename); - } + /* SASL cancellation of authentication */ + gen_send(sock, "*"); + if (ctl->server.authenticate != A_ANY) + return ok; + } else { + return ok; + } } - else if (ctl->server.protocol == P_IMAP_GSS) + +#ifdef GSSAPI + if (((ctl->server.authenticate == A_ANY && check_gss_creds("imap", ctl->server.truename) == PS_SUCCESS) + || ctl->server.authenticate == A_GSSAPI) + && strstr(capabilities, "AUTH=GSSAPI")) { - report(stderr, - _("Required GSS capability not supported by server\n")); - return(PS_AUTHFAIL); + if ((ok = do_gssauth(sock, "AUTHENTICATE", "imap", + ctl->server.truename, ctl->remotename))) + { + if (ctl->server.authenticate != A_ANY) + return ok; + } else { + return ok; + } } #endif /* GSSAPI */ -#ifdef KERBEROS_V4 - if (strstr(capabilities, "AUTH=KERBEROS_V4")) - { - if (outlevel >= O_DEBUG) - report(stdout, _("KERBEROS_V4 authentication is supported\n")); + /* + * No such luck. OK, now try the variants that mask your password + * in a challenge-response. + */ - if (ctl->server.protocol == P_IMAP_K4) + if ((ctl->server.authenticate == A_ANY && strstr(capabilities, "AUTH=CRAM-MD5")) + || ctl->server.authenticate == A_CRAM_MD5) + { + if ((ok = do_cram_md5 (sock, "AUTHENTICATE", ctl, NULL))) { - if ((ok = do_rfc1731(sock, ctl->server.truename))) - { - if (outlevel >= O_MONITOR) - report(stdout, "IMAP> *\n"); - SockWrite(sock, "*\r\n", 3); - } - - return(ok); + if(ctl->server.authenticate != A_ANY) + return ok; } - /* else fall through to ordinary AUTH=LOGIN case */ - } - else if (ctl->server.protocol == P_IMAP_K4) - { - report(stderr, - _("Required KERBEROS_V4 capability not supported by server\n")); - return(PS_AUTHFAIL); + else + return ok; } -#endif /* KERBEROS_V4 */ - if (strstr(capabilities, "AUTH=CRAM-MD5")) - { - if (outlevel >= O_DEBUG) - report (stdout, _("CRAM-MD5 authentication is supported\n")); - if (ctl->server.protocol != P_IMAP_LOGIN) - { - if ((ok = do_cram_md5 (sock, ctl))) - { - if (outlevel >= O_MONITOR) - report (stdout, "IMAP> *\n"); - SockWrite (sock, "*\r\n", 3); - } - return ok; - } +#ifdef OPIE_ENABLE + if ((ctl->server.authenticate == A_ANY + || ctl->server.authenticate == A_OTP) + && strstr(capabilities, "AUTH=X-OTP")) { + if ((ok = do_otp(sock, "AUTHENTICATE", ctl))) + { + /* SASL cancellation of authentication */ + gen_send(sock, "*"); + if(ctl->server.authenticate != A_ANY) + return ok; + } else { + return ok; + } } - else if (ctl->server.protocol == P_IMAP_CRAM_MD5) +#else + if (ctl->server.authenticate == A_OTP) { - report(stderr, - _("Required CRAM-MD5 capability not supported by server\n")); - return(PS_AUTHFAIL); + report(stderr, + GT_("Required OTP capability not compiled into fetchmail\n")); } +#endif /* OPIE_ENABLE */ #ifdef NTLM_ENABLE - if (strstr (capabilities, "AUTH=NTLM")) + if ((ctl->server.authenticate == A_ANY + || ctl->server.authenticate == A_NTLM) + && strstr (capabilities, "AUTH=NTLM")) { + if ((ok = do_imap_ntlm(sock, ctl))) + { + if(ctl->server.authenticate != A_ANY) + return ok; + } + else + return(ok); + } +#else + if (ctl->server.authenticate == A_NTLM) { - if (outlevel >= O_DEBUG) - report (stdout, _("NTLM authentication is supported\n")); - return do_imap_ntlm (sock, ctl); + report(stderr, + GT_("Required NTLM capability not compiled into fetchmail\n")); } #endif /* NTLM_ENABLE */ -#ifdef __UNUSED__ /* The Cyrus IMAP4rev1 server chokes on this */ - /* this handles either AUTH=LOGIN or AUTH-LOGIN */ - if ((imap_version >= IMAP4rev1) && (!strstr(capabilities, "LOGIN"))) { - report(stderr, - _("Required LOGIN capability not supported by server\n")); - return PS_AUTHFAIL; - }; -#endif /* __UNUSED__ */ - + /* + * We're stuck with sending the password en clair. + * The reason for this odd-looking logic is that some + * servers return LOGINDISABLED even though login + * actually works. So arrange things in such a way that + * setting auth passwd makes it ignore this capability. + */ + if((ctl->server.authenticate==A_ANY&&!strstr(capabilities,"LOGINDISABLED")) + || ctl->server.authenticate == A_PASSWORD) { /* these sizes guarantee no buffer overflow */ - char remotename[NAMELEN*2+1], password[PASSWORDLEN*2+1]; + char *remotename, *password; + size_t rnl, pwl; + rnl = 2 * strlen(ctl->remotename) + 1; + pwl = 2 * strlen(ctl->password) + 1; + remotename = (char *)xmalloc(rnl); + password = (char *)xmalloc(pwl); - imap_canonicalize(remotename, ctl->remotename, NAMELEN); - imap_canonicalize(password, ctl->password, PASSWORDLEN); + imap_canonicalize(remotename, ctl->remotename, rnl); + imap_canonicalize(password, ctl->password, pwl); + + snprintf(shroud, sizeof (shroud), "\"%s\"", password); ok = gen_transact(sock, "LOGIN \"%s\" \"%s\"", remotename, password); + memset(shroud, 0x55, sizeof(shroud)); + shroud[0] = '\0'; + memset(password, 0x55, strlen(password)); + free(password); + free(remotename); + if (ok) + { + if(ctl->server.authenticate != A_ANY) + return ok; + } + else + return(ok); } - if (ok) - return(ok); - - return(PS_SUCCESS); + return(ok); } static int internal_expunge(int sock) @@ -1021,9 +637,27 @@ static int internal_expunge(int sock) { int ok; + actual_deletions = 0; + if ((ok = gen_transact(sock, "EXPUNGE"))) return(ok); + /* if there is a mismatch between the number of mails which should + * have been expunged and the number of mails actually expunged, + * another email client may be deleting mails. Quit here, + * otherwise fetchmail gets out-of-sync with the imap server, + * reports the wrong size to the SMTP server on MAIL FROM: and + * triggers a "message ... was not the expected length" error on + * every subsequent mail */ + if (deletions > 0 && deletions != actual_deletions) + { + report(stderr, + GT_("mail expunge mismatch (%d actual != %d expected)\n"), + actual_deletions, deletions); + deletions = 0; + return(PS_ERROR); + } + expunged += deletions; deletions = 0; @@ -1034,6 +668,175 @@ static int internal_expunge(int sock) return(PS_SUCCESS); } +static int imap_idle(int sock) +/* start an RFC2177 IDLE, or fake one if unsupported */ +{ + int ok; + + saved_timeout = mytimeout; + + if (has_idle) { + /* special timeout to terminate the IDLE and re-issue it + * at least every 28 minutes: + * (the server may have an inactivity timeout) */ + mytimeout = idle_timeout = 1680; /* 28 min */ + time(&idle_start_time); + stage = STAGE_IDLE; + /* enter IDLE mode */ + ok = gen_transact(sock, "IDLE"); + + if (ok == PS_IDLETIMEOUT) { + /* send "DONE" continuation */ + SockWrite(sock, "DONE\r\n", 6); + if (outlevel >= O_MONITOR) + report(stdout, "IMAP> DONE\n"); + /* reset stage and timeout here: we are not idling any more */ + mytimeout = saved_timeout; + stage = STAGE_GETRANGE; + /* get OK IDLE message */ + ok = imap_ok(sock, NULL); + } + } else { /* no idle support, fake it */ + /* Note: stage and timeout have not been changed here as NOOP + * does not idle */ + ok = gen_transact(sock, "NOOP"); + + /* no error, but no new mail either */ + if (ok == PS_SUCCESS && recentcount == 0) + { + /* There are some servers who do send new mail + * notification out of the blue. This is in compliance + * with RFC 2060 section 5.3. Wait for that with a low + * timeout */ + mytimeout = idle_timeout = 28; + time(&idle_start_time); + stage = STAGE_IDLE; + /* We are waiting for notification; no tag needed */ + tag[0] = '\0'; + /* wait (briefly) for an unsolicited status update */ + ok = imap_ok(sock, NULL); + if (ok == PS_IDLETIMEOUT) { + /* no notification came; ok */ + ok = PS_SUCCESS; + } + } + } + + /* restore normal timeout value */ + set_timeout(0); + mytimeout = saved_timeout; + stage = STAGE_GETRANGE; + + return(ok); +} + +static int imap_search(int sock, struct query *ctl, int count) +/* search for unseen messages */ +{ + int ok; + char buf[MSGBUFSIZE+1], *cp; + + /* Don't count deleted messages. Enabled only for IMAP4 servers or + * higher and only when keeping mails. This flag will have an + * effect only when user has marked some unread mails for deletion + * using another e-mail client. */ + flag skipdeleted = ctl->keep; + const char *undeleted; + + /* structure to keep the end portion of the incomplete response */ + struct RecvSplit rs; + + /* startcount is higher than count so that if there are no + * unseen messages, imap_getsizes() will not need to do + * anything! */ + startcount = count + 1; + + for (;;) + { + undeleted = (skipdeleted ? " UNDELETED" : ""); + gen_send(sock, "SEARCH UNSEEN%s", undeleted); + gen_recv_split_init("* SEARCH", &rs); + while ((ok = imap_response(sock, buf, &rs)) == PS_UNTAGGED) + { + if ((cp = strstr(buf, "* SEARCH"))) + { + char *ep; + + cp += 8; /* skip "* SEARCH" */ + while (*cp && unseen < count) + { + /* skip whitespace */ + while (*cp && isspace((unsigned char)*cp)) + cp++; + if (*cp) + { + unsigned long um; + + errno = 0; + um = strtoul(cp,&ep,10); + if (errno == 0 && ep > cp + && um <= INT_MAX && um <= (unsigned)count) + { + unseen_messages[unseen++] = um; + if (outlevel >= O_DEBUG) + report(stdout, GT_("%lu is unseen\n"), um); + if (startcount > um) + startcount = um; + } + cp = ep; + } + } + } + } + if (ok != PS_ERROR) /* success or non-protocol error */ + return(ok); + + /* there is a protocol error. try a different search command. */ + if (skipdeleted) + { + /* retry with "SEARCH UNSEEN" */ + skipdeleted = FALSE; + continue; + } + /* try with "FETCH 1:n FLAGS" */ + break; + } + + if (count == 1) + gen_send(sock, "FETCH %d FLAGS", count); + else + gen_send(sock, "FETCH %d:%d FLAGS", 1, count); + while ((ok = imap_response(sock, buf, NULL)) == PS_UNTAGGED) + { + unsigned int num; + int consumed; + + /* expected response format: + * IMAP< * 1 FETCH (FLAGS (\Seen)) + * IMAP< * 2 FETCH (FLAGS (\Seen \Deleted)) + * IMAP< * 3 FETCH (FLAGS ()) + * IMAP< * 4 FETCH (FLAGS (\Recent)) + * IMAP< * 5 FETCH (UID 10 FLAGS (\Recent)) + */ + if (unseen < count + && sscanf(buf, "* %u %n", &num, &consumed) == 1 + && 0 == strncasecmp(buf+consumed, "FETCH", 5) + && isspace((unsigned char)buf[consumed+5]) + && num >= 1 && num <= (unsigned)count + && strstr(buf, "FLAGS ") + && !strstr(buf, "\\SEEN") + && !strstr(buf, "\\DELETED")) + { + unseen_messages[unseen++] = num; + if (outlevel >= O_DEBUG) + report(stdout, GT_("%u is unseen\n"), num); + if (startcount > num) + startcount = num; + } + } + return(ok); +} + static int imap_getrange(int sock, struct query *ctl, const char *folder, @@ -1042,121 +845,256 @@ static int imap_getrange(int sock, { int ok; - imap_phase = PHASE_GETRANGE; - /* find out how many messages are waiting */ - *bytes = recent = unseen = -1; + *bytes = -1; if (pass > 1) { - /* - * We have to have an expunge here, otherwise the re-poll will - * infinite-loop picking up un-expunged messages -- unless the - * expunge period is one and we've been nuking each message - * just after deletion. - */ - ok = 0; - if (deletions && expunge_period != 1) - internal_expunge(sock); - count = -1; - if (ok || gen_transact(sock, "NOOP")) + /* deleted mails have already been expunged by + * end_mailbox_poll(). + * + * recentcount is already set here by the last imap command which + * returned EXISTS on detecting new mail. if recentcount is 0, wait + * for new mail. + * + * this is a while loop because imap_idle() might return on other + * mailbox changes also */ + while (recentcount == 0 && do_idle) { + smtp_close(ctl, 1); + ok = imap_idle(sock); + if (ok) + { + report(stderr, GT_("re-poll failed\n")); + return(ok); + } + } + /* if recentcount is 0, return no mail */ + if (recentcount == 0) + count = 0; + if (outlevel >= O_DEBUG) + report(stdout, ngettext("%d message waiting after re-poll\n", + "%d messages waiting after re-poll\n", + count), count); + } + else + { + oldcount = count = 0; + ok = gen_transact(sock, + check_only ? "EXAMINE \"%s\"" : "SELECT \"%s\"", + folder ? folder : "INBOX"); + /* imap_ok returns PS_LOCKBUSY for READ-ONLY folders, + * which we can safely use in fetchall keep only */ + if (ok == PS_LOCKBUSY && ctl->fetchall && ctl-> keep) + ok = 0; + + if (ok != 0) { - report(stderr, _("re-poll failed\n")); + report(stderr, GT_("mailbox selection failed\n")); return(ok); } - else if (count == -1) /* no EXISTS response to NOOP */ + else if (outlevel >= O_DEBUG) + report(stdout, ngettext("%d message waiting after first poll\n", + "%d messages waiting after first poll\n", + count), count); + + /* + * We should have an expunge here to + * a) avoid fetching deleted mails during 'fetchall' + * b) getting a wrong count of mails during 'no fetchall' + */ + if (!check_only && !ctl->keep && count > 0) + { + ok = internal_expunge(sock); + if (ok) + { + report(stderr, GT_("expunge failed\n")); + return(ok); + } + if (outlevel >= O_DEBUG) + report(stdout, ngettext("%d message waiting after expunge\n", + "%d messages waiting after expunge\n", + count), count); + } + + if (count == 0 && do_idle) { - count = recent = 0; - unseen = -1; + /* no messages? then we may need to idle until we get some */ + while (count == 0) { + ok = imap_idle(sock); + if (ok) + { + report(stderr, GT_("re-poll failed\n")); + return(ok); + } + } + if (outlevel >= O_DEBUG) + report(stdout, ngettext("%d message waiting after re-poll\n", + "%d messages waiting after re-poll\n", + count), count); } } - else + + *countp = oldcount = count; + recentcount = 0; + startcount = 1; + + /* OK, now get a count of unseen messages and their indices */ + if (!ctl->fetchall && count > 0) { - if (!check_only) - ok = gen_transact(sock, "SELECT %s", folder ? folder : "INBOX"); - else - ok = gen_transact(sock, "EXAMINE %s", folder ? folder : "INBOX"); + if (unseen_messages) + free(unseen_messages); + unseen_messages = (unsigned int *)xmalloc(count * sizeof(unsigned int)); + memset(unseen_messages, 0, count * sizeof(unsigned int)); + unseen = 0; + + ok = imap_search(sock, ctl, count); if (ok != 0) { - report(stderr, _("mailbox selection failed\n")); + report(stderr, GT_("search for unseen messages failed\n")); return(ok); } - } - - *countp = count; - /* - * Note: because IMAP has an is_old method, this number is used - * only for the "X messages (Y unseen)" notification. Accordingly - * it doesn't matter much that it can be wrong (e.g. if we see an - * UNSEEN response but not all messages above the first UNSEEN one - * are likewise). - */ - if (unseen >= 0) /* optional, but better if we see it */ - *newp = count - unseen + 1; - else if (recent >= 0) /* mandatory */ - *newp = recent; - else - *newp = -1; /* should never happen, RECENT is mandatory */ + if (outlevel >= O_DEBUG && unseen > 0) + report(stdout, GT_("%u is first unseen\n"), startcount); + } else + unseen = -1; + *newp = unseen; expunged = 0; + deletions = 0; return(PS_SUCCESS); } -static int imap_getsizes(int sock, int count, int *sizes) -/* capture the sizes of all messages */ +static int imap_getpartialsizes(int sock, int first, int last, int *sizes) +/* capture the sizes of messages #first-#last */ { char buf [MSGBUFSIZE+1]; - - imap_phase = PHASE_GETSIZES; + int ok; /* * Some servers (as in, PMDF5.1-9.1 under OpenVMS 6.1) * won't accept 1:1 as valid set syntax. Some implementors * should be taken out and shot for excessive anality. + * + * Microsoft Exchange (brain-dead piece of crap that it is) + * sometimes gets its knickers in a knot about bodiless messages. + * You may see responses like this: + * + * fetchmail: IMAP> A0004 FETCH 1:9 RFC822.SIZE + * fetchmail: IMAP< * 2 FETCH (RFC822.SIZE 1187) + * fetchmail: IMAP< * 3 FETCH (RFC822.SIZE 3954) + * fetchmail: IMAP< * 4 FETCH (RFC822.SIZE 1944) + * fetchmail: IMAP< * 5 FETCH (RFC822.SIZE 2933) + * fetchmail: IMAP< * 6 FETCH (RFC822.SIZE 1854) + * fetchmail: IMAP< * 7 FETCH (RFC822.SIZE 34054) + * fetchmail: IMAP< * 8 FETCH (RFC822.SIZE 5561) + * fetchmail: IMAP< * 9 FETCH (RFC822.SIZE 1101) + * fetchmail: IMAP< A0004 NO The requested item could not be found. + * + * This means message 1 has only headers. For kicks and grins + * you can telnet in and look: + * A003 FETCH 1 FULL + * A003 NO The requested item could not be found. + * A004 fetch 1 rfc822.header + * A004 NO The requested item could not be found. + * A006 FETCH 1 BODY + * * 1 FETCH (BODY ("TEXT" "PLAIN" ("CHARSET" "US-ASCII") NIL NIL "7BIT" 35 3)) + * A006 OK FETCH completed. + * + * To get around this, we treat the final NO as success and count + * on the fact that the sizes array has been preinitialized with a + * known-bad size value. */ - if (count == 1) - gen_send(sock, "FETCH 1 RFC822.SIZE", count); - else - gen_send(sock, "FETCH 1:%d RFC822.SIZE", count); - for (;;) - { - int num, size, ok; - if ((ok = gen_recv(sock, buf, sizeof(buf)))) - return(ok); - if (strstr(buf, "OK")) - break; - else if (sscanf(buf, "* %d FETCH (RFC822.SIZE %d)", &num, &size) == 2) - sizes[num - 1] = size; + /* expunges change the fetch numbers */ + first -= expunged; + last -= expunged; + + if (last == first) + gen_send(sock, "FETCH %d RFC822.SIZE", last); + else if (last > first) + gen_send(sock, "FETCH %d:%d RFC822.SIZE", first, last); + else /* no unseen messages! */ + return(PS_SUCCESS); + while ((ok = imap_response(sock, buf, NULL)) == PS_UNTAGGED) + { + unsigned int size; + int num; + int consumed; + char *ptr; + + /* expected response formats: + * IMAP> A0005 FETCH 1 RFC822.SIZE + * IMAP< * 1 FETCH (RFC822.SIZE 1187) + * IMAP< * 1 FETCH (UID 16 RFC822.SIZE 1447) + */ + if (sscanf(buf, "* %d %n", &num, &consumed) == 1 + && 0 == strncasecmp(buf + consumed, "FETCH", 5) + && isspace((unsigned char)buf[consumed + 5]) + && (ptr = strstr(buf, "RFC822.SIZE ")) + && sscanf(ptr, "RFC822.SIZE %u", &size) == 1) + { + if (num >= first && num <= last) + sizes[num - first] = size; + else + report(stderr, + GT_("Warning: ignoring bogus data for message sizes returned by the server.\n")); + } } + return(ok); +} - imap_phase = PHASE_FETCH; - - return(PS_SUCCESS); +static int imap_getsizes(int sock, int count, int *sizes) +/* capture the sizes of all messages */ +{ + return imap_getpartialsizes(sock, 1, count, sizes); } static int imap_is_old(int sock, struct query *ctl, int number) /* is the given message old? */ { - int ok; + flag seen = TRUE; + int i; - /* expunges change the fetch numbers */ - number -= expunged; + (void)sock; + (void)ctl; + /* + * Expunges change the fetch numbers, but unseen_messages contains + * indices from before any expungees were done. So neither the + * argument nor the values in message_sequence need to be decremented. + */ - if ((ok = gen_transact(sock, "FETCH %d FLAGS", number)) != 0) - return(PS_ERROR); + seen = TRUE; + for (i = 0; i < unseen; i++) + if (unseen_messages[i] == (unsigned)number) + { + seen = FALSE; + break; + } return(seen); } +#if 0 +static char *skip_token(char *ptr) +{ + while(isspace((unsigned char)*ptr)) ptr++; + while(!isspace((unsigned char)*ptr) && !iscntrl((unsigned char)*ptr)) ptr++; + while(isspace((unsigned char)*ptr)) ptr++; + return(ptr); +} +#endif + static int imap_fetch_headers(int sock, struct query *ctl,int number,int *lenp) /* request headers of nth message */ { char buf [MSGBUFSIZE+1]; int num; + int ok; + char *ptr; + (void)ctl; /* expunges change the fetch numbers */ number -= expunged; @@ -1167,18 +1105,50 @@ static int imap_fetch_headers(int sock, struct query *ctl,int number,int *lenp) gen_send(sock, "FETCH %d RFC822.HEADER", number); /* looking for FETCH response */ - do { - int ok; + if ((ok = imap_response(sock, buf, NULL)) == PS_UNTAGGED) + { + int consumed; + /* expected response formats: + * IMAP> A0006 FETCH 1 RFC822.HEADER + * IMAP< * 1 FETCH (RFC822.HEADER {1360} + * IMAP< * 1 FETCH (UID 16 RFC822.HEADER {1360} + * IMAP< * 1 FETCH (UID 16 RFC822.SIZE 4029 RFC822.HEADER {1360} + */ + if (sscanf(buf, "* %d %n", &num, &consumed) == 1 + && 0 == strncasecmp(buf + consumed, "FETCH", 5) + && isspace((unsigned char)buf[5+consumed]) + && num == number + && (ptr = strstr(buf, "RFC822.HEADER")) + && sscanf(ptr, "RFC822.HEADER {%d}%n", lenp, &consumed) == 1 + && ptr[consumed-1] == '}') + { + return(PS_SUCCESS); + } - if ((ok = gen_recv(sock, buf, sizeof(buf)))) - return(ok); - } while - (sscanf(buf+2, "%d FETCH (%*s {%d}", &num, lenp) != 2); + /* wait for a tagged response */ + imap_ok (sock, 0); - if (num != number) + /* try to recover for some responses */ + if (!strncmp(buf, "* NO", 4) || + !strncmp(buf, "* BAD", 5) || + strstr(buf, "FETCH ()")) + { + return(PS_TRANSIENT); + } + + /* a response which does not match any of the above */ + if (outlevel > O_SILENT) + report(stderr, GT_("Incorrect FETCH response: %s.\n"), buf); return(PS_ERROR); - else - return(PS_SUCCESS); + } + else if (ok == PS_SUCCESS) + { + /* an unexpected tagged response */ + if (outlevel > O_SILENT) + report(stderr, GT_("Incorrect FETCH response: %s.\n"), buf); + return(PS_TRANSIENT); + } + return(ok); } static int imap_fetch_body(int sock, struct query *ctl, int number, int *lenp) @@ -1187,6 +1157,7 @@ static int imap_fetch_body(int sock, struct query *ctl, int number, int *lenp) char buf [MSGBUFSIZE+1], *cp; int num; + (void)ctl; /* expunges change the fetch numbers */ number -= expunged; @@ -1196,29 +1167,27 @@ static int imap_fetch_body(int sock, struct query *ctl, int number, int *lenp) * craps out during the message, it will still be marked `unseen' on * the server. * - * However...*don't* do this if we're using keep to suppress deletion! - * In that case, marking the seen flag is the only way to prevent the - * message from being re-fetched on subsequent runs (and according - * to RFC2060 p.43 this fetch should set Seen as a side effect). + * According to RFC2060, and Mark Crispin the IMAP maintainer, + * FETCH %d BODY[TEXT] and RFC822.TEXT are "functionally + * equivalent". However, we know of at least one server that + * treats them differently in the presence of MIME attachments; + * the latter form downloads the attachment, the former does not. + * The server is InterChange. + * + * When I tried working around this by disabling use of the 4rev1 form, + * I found that doing this breaks operation with M$ Exchange. + * Annoyingly enough, Exchange's refusal to cope is technically legal + * under RFC2062. */ switch (imap_version) { case IMAP4rev1: /* RFC 2060 */ - if (!ctl->keep) - gen_send(sock, "FETCH %d BODY.PEEK[TEXT]", number); - else - gen_send(sock, "FETCH %d BODY[TEXT]", number); + default: + gen_send(sock, "FETCH %d BODY.PEEK[TEXT]", number); break; case IMAP4: /* RFC 1730 */ - if (!ctl->keep) - gen_send(sock, "FETCH %d RFC822.TEXT.PEEK", number); - else - gen_send(sock, "FETCH %d RFC822.TEXT", number); - break; - - default: /* RFC 1176 */ - gen_send(sock, "FETCH %d RFC822.TEXT", number); + gen_send(sock, "FETCH %d RFC822.TEXT.PEEK", number); break; } @@ -1234,84 +1203,80 @@ static int imap_fetch_body(int sock, struct query *ctl, int number, int *lenp) if (num != number) return(PS_ERROR); + /* Understand "NIL" as length => no body present + * (MS Exchange, BerliOS Bug #11980) */ + if (strstr(buf+10, "NIL)")) { + *lenp = 0; + return PS_SUCCESS; + } + + /* Understand the empty string. Seen on Yahoo. */ + /* XXX FIXME: we should be able to handle strings here. */ + if (strstr(buf+10, "\"\")")) { + *lenp = 0; + return PS_SUCCESS; + } + /* * Try to extract a length from the FETCH response. RFC2060 requires * it to be present, but at least one IMAP server (Novell GroupWise) - * botches this. + * botches this. The overflow check is needed because of a broken + * server called dbmail that returns huge garbage lengths. */ - if ((cp = strchr(buf, '{'))) - *lenp = atoi(cp + 1); - else + if ((cp = strchr(buf, '{'))) { + long l; char *t; + errno = 0; + ++ cp; + l = strtol(cp, &t, 10); + if (errno || t == cp || (t && !strchr(t, '}')) /* parse error */ + || l < 0 || l > INT_MAX /* range check */) { + *lenp = -1; + } else { + *lenp = l; + } + } else { *lenp = -1; /* missing length part in FETCH reponse */ + } - return(PS_SUCCESS); + return PS_SUCCESS; } -static int imap_trail(int sock, struct query *ctl, int number) +static int imap_trail(int sock, struct query *ctl, const char *tag) /* discard tail of FETCH response after reading message text */ { /* expunges change the fetch numbers */ /* number -= expunged; */ - for (;;) - { - char buf[MSGBUFSIZE+1]; - int ok; - - if ((ok = gen_recv(sock, buf, sizeof(buf)))) - return(ok); - - /* UW IMAP returns "OK FETCH", Cyrus returns "OK Completed" */ - if (strstr(buf, "OK")) - break; - -#ifdef __UNUSED__ - /* - * Any IMAP server that fails to set Seen on a BODY[TEXT] - * fetch violates RFC2060 p.43 (top). This becomes an issue - * when keep is on, because seen messages aren't deleted and - * get refetched on each poll. As a workaround, if keep is on - * we can set the Seen flag explicitly. - * - * This code isn't used yet because we don't know of any IMAP - * servers broken in this way. - */ - if (ctl->keep) - if ((ok = gen_transact(sock, - imap_version == IMAP4 - ? "STORE %d +FLAGS.SILENT (\\Seen)" - : "STORE %d +FLAGS (\\Seen)", - number))) - return(ok); -#endif /* __UNUSED__ */ - } + (void)ctl; + (void)tag; - return(PS_SUCCESS); + return imap_ok(sock, NULL); } static int imap_delete(int sock, struct query *ctl, int number) /* set delete flag for given message */ { int ok; + /* Select which flags to set on message deletion: */ + const char delflags_seen[] = "\\Seen \\Deleted"; + static const char *delflags; + /* Which environment variable to look for: */ + /* DEFAULT since many fetchmail versions <= 6.3.X */ + delflags = delflags_seen; + + (void)ctl; /* expunges change the fetch numbers */ number -= expunged; /* - * Use SILENT if possible as a minor throughput optimization. - * Note: this has been dropped from IMAP4rev1. - * * We set Seen because there are some IMAP servers (notably HP * OpenMail) that do message-receipt DSNs, but only when the seen * bit is set. This is the appropriate time -- we get here right * after the local SMTP response that says delivery was * successful. */ - if ((ok = gen_transact(sock, - imap_version == IMAP4 - ? "STORE %d +FLAGS.SILENT (\\Seen \\Deleted)" - : "STORE %d +FLAGS (\\Seen \\Deleted)", - number))) + if ((ok = gen_transact(sock, "STORE %d +FLAGS.SILENT (\\Seen \\Deleted)", number))) return(ok); else deletions++; @@ -1323,45 +1288,70 @@ static int imap_delete(int sock, struct query *ctl, int number) * the next session. */ if (NUM_NONZERO(expunge_period) && (deletions % expunge_period) == 0) - internal_expunge(sock); + { + if ((ok = internal_expunge(sock))) + return(ok); + } + + return(PS_SUCCESS); +} + +static int imap_mark_seen(int sock, struct query *ctl, int number) +/* mark the given message as seen */ +{ + (void)ctl; + + /* expunges change the message numbers */ + number -= expunged; + + return(gen_transact(sock,"STORE %d +FLAGS.SILENT (\\Seen)", number)); +} +static int imap_end_mailbox_poll(int sock, struct query *ctl) +/* cleanup mailbox before we idle or switch to another one */ +{ + (void)ctl; + if (deletions) + internal_expunge(sock); return(PS_SUCCESS); } static int imap_logout(int sock, struct query *ctl) /* send logout command */ { - imap_phase = PHASE_LOGOUT; - + (void)ctl; /* if any un-expunged deletions remain, ship an expunge now */ if (deletions) internal_expunge(sock); +#ifdef USE_SEARCH + /* Memory clean-up */ + if (unseen_messages) + free(unseen_messages); +#endif /* USE_SEARCH */ + return(gen_transact(sock, "LOGOUT")); } -const static struct method imap = +static const struct method imap = { "IMAP", /* Internet Message Access Protocol */ -#if INET6_ENABLE - "imap", - "imaps", -#else /* INET6_ENABLE */ - 143, /* standard IMAP2bis/IMAP4 port */ - 993, /* ssl IMAP2bis/IMAP4 port */ -#endif /* INET6_ENABLE */ + "imap", /* service (plain and TLS) */ + "imaps", /* service (SSL) */ TRUE, /* this is a tagged protocol */ FALSE, /* no message delimiter */ imap_ok, /* parse command response */ - imap_canonicalize, /* deal with embedded slashes and spaces */ imap_getauth, /* get authorization */ imap_getrange, /* query range of messages */ imap_getsizes, /* get sizes of messages (used for ESMTP SIZE option) */ + imap_getpartialsizes, /* get sizes of subset of messages (used for ESMTP SIZE option) */ imap_is_old, /* no UID check */ imap_fetch_headers, /* request given message headers */ imap_fetch_body, /* request given message body */ imap_trail, /* eat message trailer */ imap_delete, /* delete the message */ + imap_mark_seen, /* how to mark a message as seen */ + imap_end_mailbox_poll, /* end-of-mailbox processing */ imap_logout, /* expunge and exit */ TRUE, /* yes, we can re-poll */ };