X-Git-Url: https://git.distorted.org.uk/~mdw/qmail/blobdiff_plain/ca51b51d75ecbf78f6c5786b6d3379d296e89d85..HEAD:/addrcheck.c diff --git a/addrcheck.c b/addrcheck.c index 2ff9d13..0d36186 100644 --- a/addrcheck.c +++ b/addrcheck.c @@ -4,21 +4,41 @@ #include "str.h" #include "addrcheck.h" #include +#include +#include -/* #define DEBUG */ +#if defined(TEST) && !defined(DEBUG) +# define DEBUG +#endif #ifdef DEBUG # define D(x) x # include # include -# include #else # define D(x) #endif #define STRALLOC_INIT { 0 } +/* --- @probe@ --- * + * + * Arguments: @int cdb@ = the CDB file descriptor + * @int prefix@ = the prefix character (e.g., @'V'@) + * @const char *key, int len@ = the key string and its length + * @const char *suffix@ = a suffix to append to the key + * @const char **kp@ = where to put the full key string + * @uint32 *dlen@ = where to put the answer's length + * + * Returns: Zero if the lookup failed, @+1@ on success, or @-1@ for an + * error. + * + * Use: Probes a CDB file. The key looked up is the character + * @prefix@ followed by the first @len@ bytes of @key@, followed + * by @suffix@ (if non-null). + */ + static int probe(int cdb, int prefix, const char *key, int len, - const char *suffix, uint32 *dlen) + const char *suffix, const char **kp, uint32 *dlen) { static stralloc k = STRALLOC_INIT; char ch = prefix; @@ -27,10 +47,12 @@ static int probe(int cdb, int prefix, const char *key, int len, k.len = 0; if (!stralloc_append(&k, &ch) || !stralloc_catb(&k, key, len) || - (suffix && !stralloc_cats(&k, suffix))) + (suffix && !stralloc_cats(&k, suffix)) || + !stralloc_0(&k)) return (-1); + if (kp) *kp = k.s; D( fprintf(stderr, "*** `%.*s' -> ", k.len, k.s); ) - rc = cdb_seek(cdb, k.s, k.len, dlen); + rc = cdb_seek(cdb, k.s, k.len - 1, dlen); D( if (rc == -1) fprintf(stderr, "error: %s\n", strerror(errno)); else if (rc == 0) @@ -55,34 +77,124 @@ static int probe(int cdb, int prefix, const char *key, int len, return (rc); } -static int localprobe(int cdb, const char *key, int len, - const char *suffix, int *rc) +/* --- @localprobe@ --- * + * + * Arguments: @int cdb@ = the CDB file descriptor + * @const char *sender@ = the envelope-sender address + * @const char *key, int len@ = the (possibly defaulted) mailbox + * name to look up + * @const char *suffix@ = a suffix to append to the key (e.g., + * @"-default"@) + * @const char *tail@ = the tail of the local address matching + * any defaulted extension part + * @int *rc@ = where to put the answer + * + * Returns: Positive if found, zero if not found, negative on error. + * + * Use: Looks up a local-part in the database. This may involve + * invoking a Userv service for the recipient's owner. + */ + +static int localprobe(int cdb, const char *sender, + const char *key, int len, + const char *suffix, const char *tail, int *rc) { int err; uint32 dlen; char ch; + const char *k; + static stralloc u = STRALLOC_INIT; + static stralloc serv = STRALLOC_INIT; + int kid; + int n; + int wstat; + int p[2]; - if ((err = probe(cdb, 'L', key, len, suffix, &dlen)) < 0) + if ((err = probe(cdb, 'L', key, len, suffix, &k, &dlen)) < 0) return (-1); if (!err) { *rc = 0; return (0); } - if (dlen != 1) { errno = EINVAL; return (-1); } + if (!dlen) { errno = EINVAL; return (-1); } if (read(cdb, &ch, 1) != 1) { errno = EIO; return (-1); } + if (ch == '?') { + u.len = 0; + if (!stralloc_ready(&u, dlen - 1)) return (-1); + if (read(cdb, u.s, dlen - 1) != dlen - 1) { errno = EIO; return (-1); } + u.len = dlen - 1; + serv.len = 0; + if (!stralloc_cats(&serv, "addrcheck:") || + !stralloc_cats(&serv, k + 1) || + !stralloc_0(&serv) || + !stralloc_0(&u)) + return (-1); + D( fprintf(stderr, "asking user:\n\ + user = %s; service = %s\n tail = %s; sender = %s\n\ + address = %s; key = %s\n", + u.s, serv.s, tail, sender, key, k + 1); ) + + if (pipe(p) || (kid = fork()) == -1) + return (-1); + if (!kid) { + close(0); open("/dev/null", O_RDONLY); + dup2(p[1], 1); +#ifndef DEBUG + close(2); open("/dev/null", O_WRONLY); +#endif + close(p[0]); close(p[1]); + execl("/usr/bin/userv", "/usr/bin/userv", + "-f", "stdin=/dev/null", "-t", "10", + u.s, serv.s, + tail, sender, key, k + 1, + (char *)0); + _exit(127); + } + close(p[1]); + if (wait_pid(&wstat, kid) < 0) { close(p[0]); return (-1); } + D( fprintf(stderr, "userv exited with status %d\n", wstat); ) + if (wstat) { close (p[0]); errno = EAGAIN; return (-1); } + n = read(p[0], &ch, 1); + if (n != 1) { close (p[0]); errno = EAGAIN; return (-1); } + close(p[0]); + D( fprintf(stderr, "userv answer was `%c'\n", ch); ) + } else if (dlen != 1) { + errno = EIO; + return (-1); + } *rc = ch; return (1); } -static int local(int cdb, const char *l, int len, int *rc) +/* --- @local@ --- * + * + * Arguments: @int cdb@ = file descriptor for the CDB + * @const char *l@ = pointer to local-part to look up + * @int len@ = length of the local-part + * @const char *sender@ = envelope sender address + * @int *rc@ = where to put the answer + * + * Returns: Positive if answered, zero if lookup failed, negative on + * error. + * + * Use: Finds out whether @l@ is a valid local-part for a non-virtual + * mailbox name. Handles defaulting of extension addresses and + * suchlike. + */ + +static int local(int cdb, const char *l, int len, + const char *sender, int *rc) { int code; int err = 0; int dash; - if ((err = localprobe(cdb, l, len, 0, &code)) != 0) goto done; + if ((err = localprobe(cdb, sender, l, len, 0, l + len, &code)) != 0) + goto done; for (;;) { dash = byte_rchr(l, len, '-'); if (dash == len) break; - if ((err = localprobe(cdb, l, dash, "-default", &code)) != 0) goto done; + if ((err = localprobe(cdb, sender, + l, dash, "-default", l + dash + 1, &code)) != 0) + goto done; len = dash; } *rc = 0; @@ -99,54 +211,90 @@ done: return (err); } +/* --- @virt@ --- * + * + * Arguments: @int cdb@ = file descriptor for CDB + * @const char *u@ = the local-part of the recipient mailbox + * @int ulen@ = length of the local-part + * @const char *addr@ = the virtual domain to look up + * @int alen@ = length of the virtual domain + * @const char *sender@ = the envelope sender address + * @int *rc@ = where to put the answer + * + * Returns: Positive if found, zero if not found, negative on error. + * + * Use: Looks up the address as a virtual domain. If found, the + * local-part is appended to the local mailbox handling the + * virtual domain and passed to @local@. + */ + static int virt(int cdb, const char *u, int ulen, - const char *addr, int alen, int *rc) + const char *addr, int alen, const char *sender, int *rc) { static stralloc l = STRALLOC_INIT; uint32 dlen; int err; - if ((err = probe(cdb, 'V', addr, alen, 0, &dlen)) <= 0) + if ((err = probe(cdb, 'V', addr, alen, 0, 0, &dlen)) <= 0) return (err); if (!stralloc_ready(&l, dlen + 1)) return (-1); if (read(cdb, l.s, dlen) != dlen) { errno = EIO; return (-1); } l.s[dlen] = '-'; l.len = dlen + 1; - if (!stralloc_catb(&l, u, ulen)) return (-1); - D( printf("*** virtual map -> `%.*s'\n", l.len, l.s); ) - if (local(cdb, l.s, l.len, rc) < 0) return (-1); + if (!stralloc_catb(&l, u, ulen) || !stralloc_0(&l)) return (-1); + D( printf("*** virtual map -> `%s'\n", l.s); ) + if (local(cdb, l.s, l.len - 1, sender, rc) < 0) return (-1); return (1); } -int addrcheck(int cdb, const char *addr, int *rc) +/* --- @addrcheck@ --- * + * + * Arguments: @int cdb@ = file descriptor for CDB to look things up in + * @const char *addr@ = the (full) recipient mailbox to look up + * @const char *sender@ = the (full) envelope sender address + * @int *rc@ = where to put the answer. + * + * Returns: Nonnegative on success, or @-1@ on failure. + * + * Use: Determines whether @addr@ is a valid mailbox on this system, + * by examining the given CDB file. On exit, @*rc@ is set to + * @'+'@ if the mailbox is valid, or @'-'@ if not. + */ + +int addrcheck(int cdb, const char *addr, const char *sender, int *rc) { int at, len, dot; int err = 0; uint32 dlen; + static stralloc l = STRALLOC_INIT; len = str_len(addr); - at = str_chr(addr, '@'); + at = str_rchr(addr, '@'); if (!addr[at]) - return (local(cdb, addr, len, rc)); + return (local(cdb, addr, len, sender, rc)); - if ((err = virt(cdb, addr, at, addr, len, rc)) != 0) + if ((err = virt(cdb, addr, at, addr, len, sender, rc)) != 0) return (err); dot = at + 1; while (addr[dot]) { - if ((err = virt(cdb, addr, at, addr + dot, len - dot, rc)) != 0) + if ((err = virt(cdb, addr, at, addr + dot, len - dot, sender, rc)) != 0) return (err); dot += byte_chr(addr + dot + 1, len - dot - 1, '.') + 1; } - if ((err = probe(cdb, '@', addr + at + 1, len - at - 1, 0, &dlen)) < 0) + if ((err = probe(cdb, '@', addr + at + 1, len - at - 1, 0, 0, &dlen)) < 0) return (-1); if (!err) { *rc = 1; return (0); } if (dlen != 0) { errno = EINVAL; return (-1); } - - return (local(cdb, addr, at, rc)); + l.len = 0; + if (!stralloc_catb(&l, addr, at) || + !stralloc_0(&l)) + return (-1); + return (local(cdb, l.s, l.len - 1, sender, rc)); } #ifdef TEST + #include #include #include @@ -160,16 +308,16 @@ int main(int argc, char *argv[]) int rc; int i; - if (argc < 3) { - fprintf(stderr, "usage: addrcheck CDB ADDR...\n"); + if (argc < 4) { + fprintf(stderr, "usage: addrcheck CDB SENDER ADDR...\n"); return (1); } if ((fd = open(argv[1], O_RDONLY)) < 0) { perror(argv[1]); return (1); } - for (i = 2; i < argc; i++) { - if (addrcheck(fd, argv[i], &rc) < 0) { + for (i = 3; i < argc; i++) { + if (addrcheck(fd, argv[i], argv[2], &rc) < 0) { perror("checking"); return (1); }