X-Git-Url: https://git.exim.org/exim.git/blobdiff_plain/dcd037631f32cdaed817d40ac086f4d933f51bd0..5903c6ff59527362e869fedb565c56935ce8dd68:/src/src/dkim.c diff --git a/src/src/dkim.c b/src/src/dkim.c index d48d8a95a..2857e6398 100644 --- a/src/src/dkim.c +++ b/src/src/dkim.c @@ -2,7 +2,7 @@ * Exim - an Internet mail transport agent * *************************************************/ -/* Copyright (c) University of Cambridge, 1995 - 2016 */ +/* Copyright (c) University of Cambridge, 1995 - 2017 */ /* See the file NOTICE for conditions of use and distribution. */ /* Code for DKIM support. Other DKIM relevant code is in @@ -18,7 +18,7 @@ int dkim_verify_oldpool; pdkim_ctx *dkim_verify_ctx = NULL; pdkim_signature *dkim_signatures = NULL; pdkim_signature *dkim_cur_sig = NULL; -static BOOL dkim_collect_error = FALSE; +static const uschar * dkim_collect_error = NULL; static int dkim_exim_query_dns_txt(char *name, char *answer) @@ -48,7 +48,7 @@ for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS); uschar len = rr->data[rr_offset++]; snprintf(answer + answer_offset, PDKIM_DNS_TXT_MAX_RECLEN - answer_offset, - "%.*s", (int)len, (char *) (rr->data + rr_offset)); + "%.*s", (int)len, CS (rr->data + rr_offset)); rr_offset += len; answer_offset += len; if (answer_offset >= PDKIM_DNS_TXT_MAX_RECLEN) @@ -88,7 +88,7 @@ if (dkim_verify_ctx) dkim_verify_ctx = pdkim_init_verify(&dkim_exim_query_dns_txt, dot_stuffing); dkim_collect_input = !!dkim_verify_ctx; -dkim_collect_error = FALSE; +dkim_collect_error = NULL; /* Start feed up with any cached data */ receive_get_cache(); @@ -104,11 +104,11 @@ int rc; store_pool = POOL_PERM; if ( dkim_collect_input - && (rc = pdkim_feed(dkim_verify_ctx, CS data, len)) != PDKIM_OK) + && (rc = pdkim_feed(dkim_verify_ctx, data, len)) != PDKIM_OK) { + dkim_collect_error = pdkim_errstr(rc); log_write(0, LOG_MAIN, - "DKIM: validation error: %.100s", pdkim_errstr(rc)); - dkim_collect_error = TRUE; + "DKIM: validation error: %.100s", dkim_collect_error); dkim_collect_input = FALSE; } store_pool = dkim_verify_oldpool; @@ -118,23 +118,22 @@ store_pool = dkim_verify_oldpool; void dkim_exim_verify_finish(void) { -pdkim_signature *sig = NULL; -int dkim_signers_size = 0; -int dkim_signers_ptr = 0; -dkim_signers = NULL; -int rc; +pdkim_signature * sig = NULL; +int dkim_signers_size = 0, dkim_signers_ptr = 0, rc; +const uschar * errstr; store_pool = POOL_PERM; /* Delete eventual previous signature chain */ +dkim_signers = NULL; dkim_signatures = NULL; if (dkim_collect_error) { log_write(0, LOG_MAIN, - "DKIM: Error while running this message through validation," - " disabling signature verification."); + "DKIM: Error during validation, disabling signature verification: %.100s", + dkim_collect_error); dkim_disable_verify = TRUE; goto out; } @@ -143,46 +142,49 @@ dkim_collect_input = FALSE; /* Finish DKIM operation and fetch link to signatures chain */ -if ((rc = pdkim_feed_finish(dkim_verify_ctx, &dkim_signatures)) != PDKIM_OK) +rc = pdkim_feed_finish(dkim_verify_ctx, &dkim_signatures, &errstr); +if (rc != PDKIM_OK) { - log_write(0, LOG_MAIN, - "DKIM: validation error: %.100s", pdkim_errstr(rc)); + log_write(0, LOG_MAIN, "DKIM: validation error: %.100s%s%s", pdkim_errstr(rc), + errstr ? ": " : "", errstr ? errstr : US""); goto out; } for (sig = dkim_signatures; sig; sig = sig->next) { - int size = 0; - int ptr = 0; + int size = 0, ptr = 0; + uschar * logmsg = NULL, * s; /* Log a line for each signature */ - uschar *logmsg = string_append(NULL, &size, &ptr, 5, - string_sprintf("d=%s s=%s c=%s/%s a=%s b=%d ", - sig->domain, - sig->selector, - sig->canon_headers == PDKIM_CANON_SIMPLE ? "simple" : "relaxed", - sig->canon_body == PDKIM_CANON_SIMPLE ? "simple" : "relaxed", - sig->algo == PDKIM_ALGO_RSA_SHA256 - ? "rsa-sha256" - : sig->algo == PDKIM_ALGO_RSA_SHA1 ? "rsa-sha1" : "err", - (int)sig->sighash.len > -1 ? sig->sighash.len * 8 : 0 - ), - - sig->identity ? string_sprintf("i=%s ", sig->identity) : US"", - sig->created > 0 ? string_sprintf("t=%lu ", sig->created) : US"", - sig->expires > 0 ? string_sprintf("x=%lu ", sig->expires) : US"", - sig->bodylength > -1 ? string_sprintf("l=%lu ", sig->bodylength) : US"" - ); + if (!(s = sig->domain)) s = US""; + logmsg = string_append(logmsg, &size, &ptr, 2, "d=", s); + if (!(s = sig->selector)) s = US""; + logmsg = string_append(logmsg, &size, &ptr, 2, " s=", s); + logmsg = string_append(logmsg, &size, &ptr, 7, + " c=", sig->canon_headers == PDKIM_CANON_SIMPLE ? "simple" : "relaxed", + "/", sig->canon_body == PDKIM_CANON_SIMPLE ? "simple" : "relaxed", + " a=", sig->algo == PDKIM_ALGO_RSA_SHA256 + ? "rsa-sha256" + : sig->algo == PDKIM_ALGO_RSA_SHA1 ? "rsa-sha1" : "err", + string_sprintf(" b=%d", + (int)sig->sighash.len > -1 ? sig->sighash.len * 8 : 0)); + if ((s= sig->identity)) logmsg = string_append(logmsg, &size, &ptr, 2, " i=", s); + if (sig->created > 0) logmsg = string_append(logmsg, &size, &ptr, 1, + string_sprintf(" t=%lu", sig->created)); + if (sig->expires > 0) logmsg = string_append(logmsg, &size, &ptr, 1, + string_sprintf(" x=%lu", sig->expires)); + if (sig->bodylength > -1) logmsg = string_append(logmsg, &size, &ptr, 1, + string_sprintf(" l=%lu", sig->bodylength)); switch (sig->verify_status) { case PDKIM_VERIFY_NONE: - logmsg = string_append(logmsg, &size, &ptr, 1, "[not verified]"); + logmsg = string_append(logmsg, &size, &ptr, 1, " [not verified]"); break; case PDKIM_VERIFY_INVALID: - logmsg = string_append(logmsg, &size, &ptr, 1, "[invalid - "); + logmsg = string_append(logmsg, &size, &ptr, 1, " [invalid - "); switch (sig->verify_ext_status) { case PDKIM_VERIFY_INVALID_PUBKEY_UNAVAILABLE: @@ -219,7 +221,7 @@ for (sig = dkim_signatures; sig; sig = sig->next) case PDKIM_VERIFY_FAIL: logmsg = - string_append(logmsg, &size, &ptr, 1, "[verification failed - "); + string_append(logmsg, &size, &ptr, 1, " [verification failed - "); switch (sig->verify_ext_status) { case PDKIM_VERIFY_FAIL_BODY: @@ -239,7 +241,7 @@ for (sig = dkim_signatures; sig; sig = sig->next) case PDKIM_VERIFY_PASS: logmsg = - string_append(logmsg, &size, &ptr, 1, "[verification succeeded]"); + string_append(logmsg, &size, &ptr, 1, " [verification succeeded]"); break; } @@ -248,27 +250,17 @@ for (sig = dkim_signatures; sig; sig = sig->next) /* Build a colon-separated list of signing domains (and identities, if present) in dkim_signers */ - dkim_signers = string_append(dkim_signers, - &dkim_signers_size, - &dkim_signers_ptr, 2, sig->domain, ":"); + if (sig->domain) + dkim_signers = string_append_listele(dkim_signers, &dkim_signers_size, + &dkim_signers_ptr, ':', sig->domain); if (sig->identity) - dkim_signers = string_append(dkim_signers, - &dkim_signers_size, - &dkim_signers_ptr, 2, sig->identity, ":"); + dkim_signers = string_append_listele(dkim_signers, &dkim_signers_size, + &dkim_signers_ptr, ':', sig->identity); /* Process next signature */ } -/* NULL-terminate and chop the last colon from the domain list */ - -if (dkim_signers) - { - dkim_signers[dkim_signers_ptr] = '\0'; - if (Ustrlen(dkim_signers) > 0) - dkim_signers[Ustrlen(dkim_signers) - 1] = '\0'; - } - out: store_pool = dkim_verify_oldpool; } @@ -458,15 +450,19 @@ switch (what) } +/* Generate signatures for the given file, returning a string. +If a prefix is given, prepend it to the file for the calculations. +*/ + uschar * -dkim_exim_sign(int dkim_fd, struct ob_dkim * dkim) +dkim_exim_sign(int fd, off_t off, uschar * prefix, + struct ob_dkim * dkim, const uschar ** errstr) { const uschar * dkim_domain; int sep = 0; uschar *seen_items = NULL; int seen_items_size = 0; int seen_items_offset = 0; -uschar itembuf[256]; uschar *dkim_canon_expanded; uschar *dkim_sign_headers_expanded; uschar *dkim_private_key_expanded; @@ -479,7 +475,7 @@ pdkim_signature *signature; int pdkim_canon; int pdkim_rc; int sread; -char buf[4096]; +uschar buf[4096]; int save_errno = 0; int old_pool = store_pool; @@ -495,10 +491,9 @@ if (!(dkim_domain = expand_cstring(dkim->dkim_domain))) /* Set $dkim_domain expansion variable to each unique domain in list. */ -while ((dkim_signing_domain = string_nextinlist(&dkim_domain, &sep, - itembuf, sizeof(itembuf)))) +while ((dkim_signing_domain = string_nextinlist(&dkim_domain, &sep, NULL, 0))) { - if (!dkim_signing_domain || dkim_signing_domain[0] == '\0') + if (dkim_signing_domain[0] == '\0') continue; /* Only sign once for each domain, no matter how often it @@ -581,7 +576,7 @@ while ((dkim_signing_domain = string_nextinlist(&dkim_domain, &sep, if (dkim_private_key_expanded[0] == '/') { - int privkey_fd = 0; + int privkey_fd, off = 0, len; /* Looks like a filename, load the private key. */ @@ -595,24 +590,33 @@ while ((dkim_signing_domain = string_nextinlist(&dkim_domain, &sep, goto bad; } - if (read(privkey_fd, big_buffer, big_buffer_size - 2) < 0) + do { - log_write(0, LOG_MAIN|LOG_PANIC, "unable to read private key file: %s", - dkim_private_key_expanded); - goto bad; + if ((len = read(privkey_fd, big_buffer + off, big_buffer_size - 2 - off)) < 0) + { + (void) close(privkey_fd); + log_write(0, LOG_MAIN|LOG_PANIC, "unable to read private key file: %s", + dkim_private_key_expanded); + goto bad; + } + off += len; } + while (len > 0); (void) close(privkey_fd); + big_buffer[off] = '\0'; dkim_private_key_expanded = big_buffer; } - ctx = pdkim_init_sign(CS dkim_signing_domain, + if (!(ctx = pdkim_init_sign(CS dkim_signing_domain, CS dkim_signing_selector, CS dkim_private_key_expanded, PDKIM_ALGO_RSA_SHA256, dkim->dot_stuffed, - &dkim_exim_query_dns_txt - ); + &dkim_exim_query_dns_txt, + errstr + ))) + goto bad; dkim_private_key_expanded[0] = '\0'; pdkim_set_optional(ctx, CS dkim_sign_headers_expanded, @@ -620,11 +624,15 @@ while ((dkim_signing_domain = string_nextinlist(&dkim_domain, &sep, pdkim_canon, pdkim_canon, -1, 0, 0); - lseek(dkim_fd, 0, SEEK_SET); + if (prefix) + pdkim_feed(ctx, prefix, Ustrlen(prefix)); - while ((sread = read(dkim_fd, &buf, sizeof(buf))) > 0) - if ((pdkim_rc = pdkim_feed(ctx, buf, sread)) != PDKIM_OK) - goto pk_bad; + if (lseek(fd, off, SEEK_SET) < 0) + sread = -1; + else + while ((sread = read(fd, &buf, sizeof(buf))) > 0) + if ((pdkim_rc = pdkim_feed(ctx, buf, sread)) != PDKIM_OK) + goto pk_bad; /* Handle failed read above. */ if (sread == -1) @@ -634,7 +642,7 @@ while ((dkim_signing_domain = string_nextinlist(&dkim_domain, &sep, goto bad; } - if ((pdkim_rc = pdkim_feed_finish(ctx, &signature)) != PDKIM_OK) + if ((pdkim_rc = pdkim_feed_finish(ctx, &signature, errstr)) != PDKIM_OK) goto pk_bad; sigbuf = string_append(sigbuf, &sigsize, &sigptr, 2,