cregit-Linux how code gets into the kernel

Release 4.10 fs/cifs/smb2transport.c

Directory: fs/cifs
/*
 *   fs/cifs/smb2transport.c
 *
 *   Copyright (C) International Business Machines  Corp., 2002, 2011
 *                 Etersoft, 2012
 *   Author(s): Steve French (sfrench@us.ibm.com)
 *              Jeremy Allison (jra@samba.org) 2006
 *              Pavel Shilovsky (pshilovsky@samba.org) 2012
 *
 *   This library is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU Lesser General Public License as published
 *   by the Free Software Foundation; either version 2.1 of the License, or
 *   (at your option) any later version.
 *
 *   This library is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
 *   the GNU Lesser General Public License for more details.
 *
 *   You should have received a copy of the GNU Lesser General Public License
 *   along with this library; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include <linux/fs.h>
#include <linux/list.h>
#include <linux/wait.h>
#include <linux/net.h>
#include <linux/delay.h>
#include <linux/uaccess.h>
#include <asm/processor.h>
#include <linux/mempool.h>
#include <linux/highmem.h>
#include "smb2pdu.h"
#include "cifsglob.h"
#include "cifsproto.h"
#include "smb2proto.h"
#include "cifs_debug.h"
#include "smb2status.h"
#include "smb2glob.h"


static int smb2_crypto_shash_allocate(struct TCP_Server_Info *server) { int rc; unsigned int size; if (server->secmech.sdeschmacsha256 != NULL) return 0; /* already allocated */ server->secmech.hmacsha256 = crypto_alloc_shash("hmac(sha256)", 0, 0); if (IS_ERR(server->secmech.hmacsha256)) { cifs_dbg(VFS, "could not allocate crypto hmacsha256\n"); rc = PTR_ERR(server->secmech.hmacsha256); server->secmech.hmacsha256 = NULL; return rc; } size = sizeof(struct shash_desc) + crypto_shash_descsize(server->secmech.hmacsha256); server->secmech.sdeschmacsha256 = kmalloc(size, GFP_KERNEL); if (!server->secmech.sdeschmacsha256) { crypto_free_shash(server->secmech.hmacsha256); server->secmech.hmacsha256 = NULL; return -ENOMEM; } server->secmech.sdeschmacsha256->shash.tfm = server->secmech.hmacsha256; server->secmech.sdeschmacsha256->shash.flags = 0x0; return 0; }

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steve frenchsteve french16691.21%150.00%
jeff laytonjeff layton168.79%150.00%
Total182100.00%2100.00%


static int smb3_crypto_shash_allocate(struct TCP_Server_Info *server) { unsigned int size; int rc; if (server->secmech.sdesccmacaes != NULL) return 0; /* already allocated */ rc = smb2_crypto_shash_allocate(server); if (rc) return rc; server->secmech.cmacaes = crypto_alloc_shash("cmac(aes)", 0, 0); if (IS_ERR(server->secmech.cmacaes)) { cifs_dbg(VFS, "could not allocate crypto cmac-aes"); kfree(server->secmech.sdeschmacsha256); server->secmech.sdeschmacsha256 = NULL; crypto_free_shash(server->secmech.hmacsha256); server->secmech.hmacsha256 = NULL; rc = PTR_ERR(server->secmech.cmacaes); server->secmech.cmacaes = NULL; return rc; } size = sizeof(struct shash_desc) + crypto_shash_descsize(server->secmech.cmacaes); server->secmech.sdesccmacaes = kmalloc(size, GFP_KERNEL); if (!server->secmech.sdesccmacaes) { cifs_dbg(VFS, "%s: Can't alloc cmacaes\n", __func__); kfree(server->secmech.sdeschmacsha256); server->secmech.sdeschmacsha256 = NULL; crypto_free_shash(server->secmech.hmacsha256); crypto_free_shash(server->secmech.cmacaes); server->secmech.hmacsha256 = NULL; server->secmech.cmacaes = NULL; return -ENOMEM; } server->secmech.sdesccmacaes->shash.tfm = server->secmech.cmacaes; server->secmech.sdesccmacaes->shash.flags = 0x0; return 0; }

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steve frenchsteve french26095.24%150.00%
jeff laytonjeff layton134.76%150.00%
Total273100.00%2100.00%


static struct cifs_ses * smb2_find_smb_ses(struct smb2_hdr *smb2hdr, struct TCP_Server_Info *server) { struct cifs_ses *ses; spin_lock(&cifs_tcp_ses_lock); list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) { if (ses->Suid != smb2hdr->SessionId) continue; spin_unlock(&cifs_tcp_ses_lock); return ses; } spin_unlock(&cifs_tcp_ses_lock); return NULL; }

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shirish pargaonkarshirish pargaonkar68100.00%1100.00%
Total68100.00%1100.00%


int smb2_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server) { int rc; unsigned char smb2_signature[SMB2_HMACSHA256_SIZE]; unsigned char *sigptr = smb2_signature; struct kvec *iov = rqst->rq_iov; struct smb2_hdr *smb2_pdu = (struct smb2_hdr *)iov[0].iov_base; struct cifs_ses *ses; ses = smb2_find_smb_ses(smb2_pdu, server); if (!ses) { cifs_dbg(VFS, "%s: Could not find session\n", __func__); return 0; } memset(smb2_signature, 0x0, SMB2_HMACSHA256_SIZE); memset(smb2_pdu->Signature, 0x0, SMB2_SIGNATURE_SIZE); rc = smb2_crypto_shash_allocate(server); if (rc) { cifs_dbg(VFS, "%s: shah256 alloc failed\n", __func__); return rc; } rc = crypto_shash_setkey(server->secmech.hmacsha256, ses->auth_key.response, SMB2_NTLMV2_SESSKEY_SIZE); if (rc) { cifs_dbg(VFS, "%s: Could not update with response\n", __func__); return rc; } rc = crypto_shash_init(&server->secmech.sdeschmacsha256->shash); if (rc) { cifs_dbg(VFS, "%s: Could not init sha256", __func__); return rc; } rc = __cifs_calc_signature(rqst, server, sigptr, &server->secmech.sdeschmacsha256->shash); if (!rc) memcpy(smb2_pdu->Signature, sigptr, SMB2_SIGNATURE_SIZE); return rc; }

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PersonTokensPropCommitsCommitProp
pavel shilovskypavel shilovsky15864.75%114.29%
shirish pargaonkarshirish pargaonkar3514.34%114.29%
steve frenchsteve french2610.66%114.29%
jeff laytonjeff layton187.38%228.57%
joe perchesjoe perches41.64%114.29%
al viroal viro31.23%114.29%
Total244100.00%7100.00%


static int generate_key(struct cifs_ses *ses, struct kvec label, struct kvec context, __u8 *key, unsigned int key_size) { unsigned char zero = 0x0; __u8 i[4] = {0, 0, 0, 1}; __u8 L[4] = {0, 0, 0, 128}; int rc = 0; unsigned char prfhash[SMB2_HMACSHA256_SIZE]; unsigned char *hashptr = prfhash; memset(prfhash, 0x0, SMB2_HMACSHA256_SIZE); memset(key, 0x0, key_size); rc = smb3_crypto_shash_allocate(ses->server); if (rc) { cifs_dbg(VFS, "%s: crypto alloc failed\n", __func__); goto smb3signkey_ret; } rc = crypto_shash_setkey(ses->server->secmech.hmacsha256, ses->auth_key.response, SMB2_NTLMV2_SESSKEY_SIZE); if (rc) { cifs_dbg(VFS, "%s: Could not set with session key\n", __func__); goto smb3signkey_ret; } rc = crypto_shash_init(&ses->server->secmech.sdeschmacsha256->shash); if (rc) { cifs_dbg(VFS, "%s: Could not init sign hmac\n", __func__); goto smb3signkey_ret; } rc = crypto_shash_update(&ses->server->secmech.sdeschmacsha256->shash, i, 4); if (rc) { cifs_dbg(VFS, "%s: Could not update with n\n", __func__); goto smb3signkey_ret; } rc = crypto_shash_update(&ses->server->secmech.sdeschmacsha256->shash, label.iov_base, label.iov_len); if (rc) { cifs_dbg(VFS, "%s: Could not update with label\n", __func__); goto smb3signkey_ret; } rc = crypto_shash_update(&ses->server->secmech.sdeschmacsha256->shash, &zero, 1); if (rc) { cifs_dbg(VFS, "%s: Could not update with zero\n", __func__); goto smb3signkey_ret; } rc = crypto_shash_update(&ses->server->secmech.sdeschmacsha256->shash, context.iov_base, context.iov_len); if (rc) { cifs_dbg(VFS, "%s: Could not update with context\n", __func__); goto smb3signkey_ret; } rc = crypto_shash_update(&ses->server->secmech.sdeschmacsha256->shash, L, 4); if (rc) { cifs_dbg(VFS, "%s: Could not update with L\n", __func__); goto smb3signkey_ret; } rc = crypto_shash_final(&ses->server->secmech.sdeschmacsha256->shash, hashptr); if (rc) { cifs_dbg(VFS, "%s: Could not generate sha256 hash\n", __func__); goto smb3signkey_ret; } memcpy(key, hashptr, key_size); smb3signkey_ret: return rc; }

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steve frenchsteve french42494.01%466.67%
shirish pargaonkarshirish pargaonkar265.76%116.67%
joe perchesjoe perches10.22%116.67%
Total451100.00%6100.00%

struct derivation { struct kvec label; struct kvec context; }; struct derivation_triplet { struct derivation signing; struct derivation encryption; struct derivation decryption; };
static int generate_smb3signingkey(struct cifs_ses *ses, const struct derivation_triplet *ptriplet) { int rc; rc = generate_key(ses, ptriplet->signing.label, ptriplet->signing.context, ses->smb3signingkey, SMB3_SIGN_KEY_SIZE); if (rc) return rc; rc = generate_key(ses, ptriplet->encryption.label, ptriplet->encryption.context, ses->smb3encryptionkey, SMB3_SIGN_KEY_SIZE); if (rc) return rc; return generate_key(ses, ptriplet->decryption.label, ptriplet->decryption.context, ses->smb3decryptionkey, SMB3_SIGN_KEY_SIZE); }

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steve frenchsteve french108100.00%1100.00%
Total108100.00%1100.00%


int generate_smb30signingkey(struct cifs_ses *ses) { struct derivation_triplet triplet; struct derivation *d; d = &triplet.signing; d->label.iov_base = "SMB2AESCMAC"; d->label.iov_len = 12; d->context.iov_base = "SmbSign"; d->context.iov_len = 8; d = &triplet.encryption; d->label.iov_base = "SMB2AESCCM"; d->label.iov_len = 11; d->context.iov_base = "ServerIn "; d->context.iov_len = 10; d = &triplet.decryption; d->label.iov_base = "SMB2AESCCM"; d->label.iov_len = 11; d->context.iov_base = "ServerOut"; d->context.iov_len = 10; return generate_smb3signingkey(ses, &triplet); }

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steve frenchsteve french145100.00%1100.00%
Total145100.00%1100.00%


int generate_smb311signingkey(struct cifs_ses *ses) { struct derivation_triplet triplet; struct derivation *d; d = &triplet.signing; d->label.iov_base = "SMB2AESCMAC"; d->label.iov_len = 12; d->context.iov_base = "SmbSign"; d->context.iov_len = 8; d = &triplet.encryption; d->label.iov_base = "SMB2AESCCM"; d->label.iov_len = 11; d->context.iov_base = "ServerIn "; d->context.iov_len = 10; d = &triplet.decryption; d->label.iov_base = "SMB2AESCCM"; d->label.iov_len = 11; d->context.iov_base = "ServerOut"; d->context.iov_len = 10; return generate_smb3signingkey(ses, &triplet); }

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steve frenchsteve french145100.00%1100.00%
Total145100.00%1100.00%


int smb3_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server) { int rc = 0; unsigned char smb3_signature[SMB2_CMACAES_SIZE]; unsigned char *sigptr = smb3_signature; struct kvec *iov = rqst->rq_iov; struct smb2_hdr *smb2_pdu = (struct smb2_hdr *)iov[0].iov_base; struct cifs_ses *ses; ses = smb2_find_smb_ses(smb2_pdu, server); if (!ses) { cifs_dbg(VFS, "%s: Could not find session\n", __func__); return 0; } memset(smb3_signature, 0x0, SMB2_CMACAES_SIZE); memset(smb2_pdu->Signature, 0x0, SMB2_SIGNATURE_SIZE); rc = crypto_shash_setkey(server->secmech.cmacaes, ses->smb3signingkey, SMB2_CMACAES_SIZE); if (rc) { cifs_dbg(VFS, "%s: Could not set key for cmac aes\n", __func__); return rc; } /* * we already allocate sdesccmacaes when we init smb3 signing key, * so unlike smb2 case we do not have to check here if secmech are * initialized */ rc = crypto_shash_init(&server->secmech.sdesccmacaes->shash); if (rc) { cifs_dbg(VFS, "%s: Could not init cmac aes\n", __func__); return rc; } rc = __cifs_calc_signature(rqst, server, sigptr, &server->secmech.sdesccmacaes->shash); if (!rc) memcpy(smb2_pdu->Signature, sigptr, SMB2_SIGNATURE_SIZE); return rc; }

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steve frenchsteve french18182.27%360.00%
shirish pargaonkarshirish pargaonkar3616.36%120.00%
al viroal viro31.36%120.00%
Total220100.00%5100.00%

/* must be called with server->srv_mutex held */
static int smb2_sign_rqst(struct smb_rqst *rqst, struct TCP_Server_Info *server) { int rc = 0; struct smb2_hdr *smb2_pdu = rqst->rq_iov[0].iov_base; if (!(smb2_pdu->Flags & SMB2_FLAGS_SIGNED) || server->tcpStatus == CifsNeedNegotiate) return rc; if (!server->session_estab) { strncpy(smb2_pdu->Signature, "BSRSPYL", 8); return rc; } rc = server->ops->calc_signature(rqst, server); return rc; }

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pavel shilovskypavel shilovsky8287.23%133.33%
jeff laytonjeff layton77.45%133.33%
steve frenchsteve french55.32%133.33%
Total94100.00%3100.00%


int smb2_verify_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server) { unsigned int rc; char server_response_sig[16]; struct smb2_hdr *smb2_pdu = (struct smb2_hdr *)rqst->rq_iov[0].iov_base; if ((smb2_pdu->Command == SMB2_NEGOTIATE) || (smb2_pdu->Command == SMB2_SESSION_SETUP) || (smb2_pdu->Command == SMB2_OPLOCK_BREAK) || (!server->session_estab)) return 0; /* * BB what if signatures are supposed to be on for session but * server does not send one? BB */ /* Do not need to verify session setups with signature "BSRSPYL " */ if (memcmp(smb2_pdu->Signature, "BSRSPYL ", 8) == 0) cifs_dbg(FYI, "dummy signature received for smb command 0x%x\n", smb2_pdu->Command); /* * Save off the origiginal signature so we can modify the smb and check * our calculated signature against what the server sent. */ memcpy(server_response_sig, smb2_pdu->Signature, SMB2_SIGNATURE_SIZE); memset(smb2_pdu->Signature, 0, SMB2_SIGNATURE_SIZE); mutex_lock(&server->srv_mutex); rc = server->ops->calc_signature(rqst, server); mutex_unlock(&server->srv_mutex); if (rc) return rc; if (memcmp(server_response_sig, smb2_pdu->Signature, SMB2_SIGNATURE_SIZE)) return -EACCES; else return 0; }

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pavel shilovskypavel shilovsky16587.77%120.00%
shirish pargaonkarshirish pargaonkar84.26%120.00%
jeff laytonjeff layton73.72%120.00%
steve frenchsteve french52.66%120.00%
joe perchesjoe perches31.60%120.00%
Total188100.00%5100.00%

/* * Set message id for the request. Should be called after wait_for_free_request * and when srv_mutex is held. */
static inline void smb2_seq_num_into_buf(struct TCP_Server_Info *server, struct smb2_hdr *hdr) { unsigned int i, num = le16_to_cpu(hdr->CreditCharge); hdr->MessageId = get_next_mid64(server); /* skip message numbers according to CreditCharge field */ for (i = 1; i < num; i++) get_next_mid(server); }

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pavel shilovskypavel shilovsky5798.28%266.67%
tim gardnertim gardner11.72%133.33%
Total58100.00%3100.00%


static struct mid_q_entry * smb2_mid_entry_alloc(const struct smb2_hdr *smb_buffer, struct TCP_Server_Info *server) { struct mid_q_entry *temp; if (server == NULL) { cifs_dbg(VFS, "Null TCP session in smb2_mid_entry_alloc\n"); return NULL; } temp = mempool_alloc(cifs_mid_poolp, GFP_NOFS); if (temp == NULL) return temp; else { memset(temp, 0, sizeof(struct mid_q_entry)); temp->mid = le64_to_cpu(smb_buffer->MessageId); temp->pid = current->pid; temp->command = smb_buffer->Command; /* Always LE */ temp->when_alloc = jiffies; temp->server = server; /* * The default is for the mid to be synchronous, so the * default callback just wakes up the current task. */ temp->callback = cifs_wake_up_task; temp->callback_data = current; } atomic_inc(&midCount); temp->mid_state = MID_REQUEST_ALLOCATED; return temp; }

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pavel shilovskypavel shilovsky13895.83%133.33%
joe perchesjoe perches32.08%133.33%
sachin prabhusachin prabhu32.08%133.33%
Total144100.00%3100.00%


static int smb2_get_mid_entry(struct cifs_ses *ses, struct smb2_hdr *buf, struct mid_q_entry **mid) { if (ses->server->tcpStatus == CifsExiting) return -ENOENT; if (ses->server->tcpStatus == CifsNeedReconnect) { cifs_dbg(FYI, "tcp session dead - return to caller to retry\n"); return -EAGAIN; } if (ses->status == CifsNew) { if ((buf->Command != SMB2_SESSION_SETUP) && (buf->Command != SMB2_NEGOTIATE)) return -EAGAIN; /* else ok - we are setting up session */ } if (ses->status == CifsExiting) { if (buf->Command != SMB2_LOGOFF) return -EAGAIN; /* else ok - we are shutting down the session */ } *mid = smb2_mid_entry_alloc(buf, ses->server); if (*mid == NULL) return -ENOMEM; spin_lock(&GlobalMid_Lock); list_add_tail(&(*mid)->qhead, &ses->server->pending_mid_q); spin_unlock(&GlobalMid_Lock); return 0; }

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pavel shilovskypavel shilovsky14383.63%133.33%
shirish pargaonkarshirish pargaonkar2514.62%133.33%
joe perchesjoe perches31.75%133.33%
Total171100.00%3100.00%


int smb2_check_receive(struct mid_q_entry *mid, struct TCP_Server_Info *server, bool log_error) { unsigned int len = get_rfc1002_length(mid->resp_buf); struct kvec iov; struct smb_rqst rqst = { .rq_iov = &iov, .rq_nvec = 1 }; iov.iov_base = (char *)mid->resp_buf; iov.iov_len = get_rfc1002_length(mid->resp_buf) + 4; dump_smb(mid->resp_buf, min_t(u32, 80, len)); /* convert the length into a more usable form */ if (len > 24 && server->sign) { int rc; rc = smb2_verify_signature(&rqst, server); if (rc) cifs_dbg(VFS, "SMB signature verification returned error = %d\n", rc); } return map_smb2_to_linux_error(mid->resp_buf, log_error); }

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pavel shilovskypavel shilovsky8862.86%240.00%
jeff laytonjeff layton4935.00%240.00%
joe perchesjoe perches32.14%120.00%
Total140100.00%5100.00%


struct mid_q_entry * smb2_setup_request(struct cifs_ses *ses, struct smb_rqst *rqst) { int rc; struct smb2_hdr *hdr = (struct smb2_hdr *)rqst->rq_iov[0].iov_base; struct mid_q_entry *mid; smb2_seq_num_into_buf(ses->server, hdr); rc = smb2_get_mid_entry(ses, hdr, &mid); if (rc) return ERR_PTR(rc); rc = smb2_sign_rqst(rqst, ses->server); if (rc) { cifs_delete_mid(mid); return ERR_PTR(rc); } return mid; }

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PersonTokensPropCommitsCommitProp
pavel shilovskypavel shilovsky8580.19%250.00%
jeff laytonjeff layton2119.81%250.00%
Total106100.00%4100.00%


struct mid_q_entry * smb2_setup_async_request(struct TCP_Server_Info *server, struct smb_rqst *rqst) { int rc; struct smb2_hdr *hdr = (struct smb2_hdr *)rqst->rq_iov[0].iov_base; struct mid_q_entry *mid; smb2_seq_num_into_buf(server, hdr); mid = smb2_mid_entry_alloc(hdr, server); if (mid == NULL) return ERR_PTR(-ENOMEM); rc = smb2_sign_rqst(rqst, server); if (rc) { DeleteMidQEntry(mid); return ERR_PTR(rc); } return mid; }

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PersonTokensPropCommitsCommitProp
pavel shilovskypavel shilovsky8583.33%250.00%
jeff laytonjeff layton1716.67%250.00%
Total102100.00%4100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
steve frenchsteve french149551.20%421.05%
pavel shilovskypavel shilovsky104935.92%421.05%
shirish pargaonkarshirish pargaonkar1986.78%210.53%
jeff laytonjeff layton1515.17%526.32%
joe perchesjoe perches170.58%15.26%
al viroal viro60.21%15.26%
sachin prabhusachin prabhu30.10%15.26%
tim gardnertim gardner10.03%15.26%
Total2920100.00%19100.00%
Directory: fs/cifs
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